Coenzyme Q10 and Its Therapeutic Potencies Against COVID-19 and Other Similar Infections: A Molecular Review

Abstract

The World Health Organization (WHO) officially declared COVID-19 as pandemic on 11 March 2020 and millions of people have so far died from the disease.2 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, and the previously known viruses SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) are known to cause threatening epidemics with severe clinical features that mostly involve the respiratory system.3 Coronaviridae family consists of enveloped viruses containing large positive-sense single-stranded RNA genomes which is restricted within a protein capsid and their envelope is covered with glycoprotein spikes in the shape of crowns.2 The spikes contain receptor binding domains and facilitate the attachment and replication of the virus.4 Angiotensin converting enzyme 2 (ACE2) is known as the mutual receptor for SARS-CoV-2 and its similar ancestor SARS-CoV5 ACE2 is considerably expressed in the lung epithelium, and its possible role in the pathogenesis of COVID-19 has been suggested in different studies.6 COVID-19 is currently considered the greatest health threat internationally and there is yet no definitive treatment for the disease. [...]current management policy has been mainly focused on the preventive and supportive approaches.1 As the virus continues to rapidly spread and infect millions of people, the urge to find a definite treatment intensifies and great research attempts are being conducted to solve this global concern. [...]the systemic inflammation and hypercytokinemia caused by acute viral infections may become suppressed by immunomodulatory and anti-apoptotic properties of CoQ10.15~17 Accordingly, some studies had reviewed the potential role of CoQ10 and other mitochondrial nutrients as therapeutic options against the systemic inflammation and mitochondrial dysfunction in COVID-19. [...]the selected full-text articles were reviewed and using thematic analysis, the molecular aspects of CoQ10 potencies against COVID-19 and other similar viral infections have been analyzed. [...]the RNA entrance, replication and consequent cell damage is not the only pathologic concern of COVID-19.20 As mentioned, the viral spike protein has a strong affinity to ACE2 and this is the key point of protein interaction and further deleterious clinical and pathological properties of COVID-19.21ACE2 is a transmembrane enzyme producing angiotensin and a heptamer opposing the action of angiotensin II (Angll), which is correlated with the pathogenesis of several diseases like cardiovascular, renal and fibrotic diseases.

Headnote

Article info

Article History:

Received: February 27, 2021 Revised: October 9, 2021 Accepted: November 6, 2021 epublished: November 7, 2021

Keywords:

Coenzyme Q1 0, Therapeutic, COVID-19, Molecular, Infection, Coronavirus

Abstract

Purpose: New lethal coronavirus disease 2019 (COVID-19), currently, has been converted to a disastrous pandemic worldwide. As there has been found no definitive treatment for the infection in this review we focused on molecular aspects of coenzyme Q (CoQ10) and possible therapeutic potencies of CoQ10 against COVID-1 9 and similar infections. Methods: This is a narrative review in which we used some authentic resources including PubMed, ISI, Scopus, Science Direct, Cochrane, and some preprint databases, the molecular aspects of CoQ10effects, regarding to the COVID-19 pathogenesis, have been analyzed and discussed.

Results: CoQ10 is an essential cofactor in the electron transport chain of the phosphorylative oxidation system. It is a powerful lipophilic antioxidant, anti-apoptotic, immunomodulatory and anti-inflammatory supplement which has been tested for the management and prevention of a variety of diseases particularly diseases with inflammatory pathogenesis. CoQ10 is a strong anti-inflammatory agent which can reduce tumor necrosis factor-a (TNF-a), interleukin (IL)-6, C-reactive protein (CRP), and other inflammatory cytokines. The cardio-protective role of CoQ10 in improving viral myocarditis and drug induced cardiotoxicity has been determined in different studies. CoQ10 could also improve the interference in the RAS system caused by COVID-19 through exerting anti-Angiotensin II effects and decreasing oxidative stress. CoQ10 passes easily through blood-brain barrier (BBB). As a neuroprotective agent CoQ10can reduce oxidative stress and modulate the immunologic reactions. These properties may help to reduce CNS inflammation and prevent BBB damage and neuronal apoptosis in COVID-1 9 patients. Conclusion: CoQ10 supplementation may prevent the COVID-19-induced morbidities with a potential protective role against the deleterious consequences of the disease, further clinical evaluations are encouraged.

Introduction

After the report of the first case of coronavirus disease 2019 (COVID-19) on 31 December 2019 in China,1 the virus rapidly spread worldwide. The World Health Organization (WHO) officially declared COVID-19 as pandemic on 11 March 2020 and millions of people have so far died from the disease.2 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, and the previously known viruses SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) are known to cause threatening epidemics with severe clinical features that mostly involve the respiratory system.3 Coronaviridae family consists of enveloped viruses containing large positive-sense single-stranded RNA genomes which is restricted within a protein capsid and their envelope is covered with glycoprotein spikes in the shape of crowns.2 The spikes contain receptor binding domains and facilitate the attachment and replication of the virus.4 Angiotensin converting enzyme 2 (ACE2) is known as the mutual receptor for SARS-CoV-2 and its similar ancestor SARS-CoV5 ACE2 is considerably expressed in the lung epithelium, and its possible role in the pathogenesis of COVID-19 has been suggested in different studies.6 COVID-19 is currently considered the greatest health threat internationally and there is yet no definitive treatment for the disease. Therefore,current management policy has been mainly focused on the preventive and supportive approaches.1 As the virus continues to rapidly spread and infect millions of people, the urge to find a definite treatment intensifies and great research attempts are being conducted to solve this global concern.

Coenzyme Q (CoQ10) is a natural lipid soluble electron transporter found in the mitochondrial membrane. It is an essential cofactor in the electron transport chain of the phosphorylative oxidation system. This coenzyme molecule could undergo oxidation/reduction reactions,7 and act as a powerful lipophilic antioxidant, anti-apoptotic, immunomodulatory and anti-inflammatory supplement which has been tested for the management and prevention of a variety of diseases specially diseases with inflammatory pathogenesis.8 The role of CoQ10 supplementation in heart failure and neurodegenerative diseases has been well established.8,9 Other clinical applications of CoQ10 have been tested in several clinical trials on patients with inflammatory diseases such as rheumatoid arthritis, fatty liver and diabetes. CoQ10 supplementation has presented ameliorative effects on serum inflammatory markers.10 Moreover, studies on critically ill and intensive care unit (ICU) patients have revealed a severe depletion of CoQ10 levels. It may indicate that CoQ10 supplementation solely or in combination with other micronutrients like carnitine and selenium could have a considerable positive effect on disease progression and treatment outcomes.11 Recent studies on CoQ10 revealed the immunomodulatory effects of this coenzyme,1214 especially in the context of viral disorders. In fact, the systemic inflammation and hypercytokinemia caused by acute viral infections may become suppressed by immunomodulatory and anti-apoptotic properties of CoQ10.15~17 Accordingly, some studies had reviewed the potential role of CoQ10 and other mitochondrial nutrients as therapeutic options against the systemic inflammation and mitochondrial dysfunction in COVID-19. Polymeropoulos18 in a brief opinion had reviewed the anti-inflammatory effects of CoQ10 in various clinical situation and encouraged further researches for assessing the correlation between the levels of CoQ10 in human body and the outcomes of COVID-19. In another comprehensive review by Pagano et al19 the evidences supporting the role of mitochondrial nutrients, such as a-lipoic acid, CoQ10 and carnitine, against acute and chronic inflammatory conditions were summarized, in this review we aimed to discuss the molecular aspects of CoQ10 supplementation against COVID-19. Herein, rather than the anti-inflammatory properties of CoQ10, we described other various pathways that CoQ10 supplementation could affect the disease pathogenesis including; antiviral, gene expression regulatory, immune modulatory, neuroprotective and cardiovascular protective properties of CoQ10. In addition, the role of CoQIO supplementation in clinical setting particularly in critically ill patients was reviewed from a molecular point of view.

Materials and Methods

The current study is a narrative molecular review. Some authentic resources including PubMed, ISI, Scopus, ScienceDirect, Cochrane, and some preprint databases such as Arxiv were searched within 2000-2021. Some sensitive keywords were used to find the most relevant articles, such as molecular, CoQ10, viral infection, COVID-19, SARS, and corona virus infection. Finally, the selected full-text articles were reviewed and using thematic analysis, the molecular aspects of CoQ10 potencies against COVID-19 and other similar viral infections have been analyzed.

Results and Discussion

Molecular basis ofSARS-CoV-2 infection and consequent

clinical characteristics of the disease

binding of SARS-CoV-2 spike to transmembrane ACE2 is not only the first step in pathogenesis of COVID-19 but also is the most fundamental. In fact, the RNA entrance, replication and consequent cell damage is not the only pathologic concern of COVID-19.20 As mentioned, the viral spike protein has a strong affinity to ACE2 and this is the key point of protein interaction and further deleterious clinical and pathological properties of COVID-19.21ACE2 is a transmembrane enzyme producing angiotensin and a heptamer opposing the action of angiotensin II (Angll), which is correlated with the pathogenesis of several diseases like cardiovascular, renal and fibrotic diseases. Further studies about Angll revealed that besides its vasoconstrictor effect, the immunologic, inflammatory, fibrogenic and leukocyte migratory effects are also considerable aspects of this molecular axis. Angll signaling pathway is transmitted through two G-protein-coupled receptors called AT and AT2. The most concerns is about ACE/Angll/AT route through which a variety of Angll adverse effects including: (1) oxidative stress production specially through NADPH oxidase enzyme upregulation, (2) inflammatory response by the activation of NF-kB translation factor and consequent tumor necrosis factor-a (TNF-a) and interleukin (IL)-6 production, (3) activating the leukocyte migratory pathway through increasing both the endothelial adhesion molecules like VCAMs and cell adhesion molecules on leukocytes, (4) contributing to endothelial dysfunction and (5) increasing the risk of arrhythmia and fibrosis through activating the proliferating pathways of fibroblasts and smooth muscle cells.22 Given the fact that these effects are all opposed by angiotensin ,23 the pathophysiology of SARS-CoV-2 becomes easy to understand. The viral spike protein interaction suppresses the inhibitory effect of ACE2 on the Angll system and consequently over-activates AT resulting in a propagated systemic inflammation and hypercytokinemia accompanied by immense oxidative stress in affected organs.20 Current studies show that the secondary hemophagocytic lymphohistiocytosis as an hyperinflammatory status, which leads to hypercytokinemia, is a common reason for death after a multiorgan failure in patients infected by COVID-19.24 These events are characterized by a cytokine storm due to the fulminant increased cytokines includes IL-2, IL-7, granulocyte colony stimulating factor, interferon-y, inducible protein 10 (IP-10), monocyte chemo-attractant protein 1 (MCP1), macrophage inflammatory protein 1-a (MlP-la), and TNF-ct.25 In another recent work, it was demonstrated that the CD4 + and CD8 + T cells counts in the patients with severe form of COVID-19 had been reduced in negative correlation with increased IL-6, IL-10 and TNF-ct, suggesting the apoptotic effect of these factors on T cells.26 It was also demonstrated that the apoptotic pathway triggered by IL-10, IL-6 and TNF-a passes through mitochondrial stress which is pursued by the activated caspase-9 and caspase-3.27 The mentioned two phenomena, systemic inflammation and oxidative stress, are the main causes of almost all clinical events in COVID-19. Pneumonia in COVID-19 is not only due to the pulmonary epithelium infection but also the increased vascular permeability, leukocyte migration and vascular hyper-inflammation play an undeniable role in the pathophysiology of the disease.28 The pathophysiology of cardiovascular effects of COVID-19 is not completely understood, but most researchers consider cytokine storm and myocardial inflammation as the key contributors to the events.29 In very recent and novel studies, the neuro-infective properties of SARS-CoV-2 have been discussed.3032 Steardo et al30 postulated that like SARS, MERS and other members of Coronaviridae, SARS-CoV-2 could infect the CNS and PNS causing neurologic impairment. The suggested mechanism of neuroinfection in COVID-19 is hematogenous and retrograde neuronal rout invasion to CNS. Furthermore, the systemic inflammatory state could cause the neuronal damage as made in many neuro-degenerative diseases. The first study about neurological involvement in COVID-19 patients ran in Wuhan, China, reported the neurological impairment and complications including: impaired consciousness, hyposmia, hypogeusia, dizziness, headache, and cerebrovascular accidents in severely ill patients, concluding that CNS and PNS involvement are signs of poor prognosis of the disease.31 Li et al33 discussed the association of respiratory failure with neuro-invasiveness of SARS-CoV-2 and demonstrated that viral invasion to the medullary cardiorespiratory centers through the root of mechanoreceptors and chemoreceptors in lower respiratory tract could cause respiratory failure in severely ill patients. (Figure 1).

Biochemical and pharmacological characteristics of coenzyme Q10

In 1957 Crane et al34 reported the first time a quinone found in oxidized and reduced forms. Coenzyme Qio or CoQio (2, 3dimethoxy-5methyl-6-decaprenyl benzoquinone) is a lipophilic vitamin-like compound which is also known as ubiquinone (oxidized) or ubiquinol (reduced). The chemical structure (Figure 2) consists of a benzoquinone ring connected to a long side chain containing 10 isoprene units.35 CoQio is endogenously synthesized from mevalonic acid and phenylalanine.36 C0Q10 is a well-defined physiological component of the mitochondrial respiratory chain which supports the generation of energy in the form of ATP by converting the energy in carbohydrates and fatty acids into the energy-rich adenosine triphosphate.37 It also reduces oxidative and nitrosative stress by decreasing the superoxide radicals and interfering with the production of peroxynitrite. C0Q10 exists in two forms in the body: reduced form also known as ubiquinol is used by the body as an endogenous antioxidant, and oxidized or ubiquinone form is an electron carrier during mitochondrial respiration.38 Due to several features including solubility in lipid and its role in the inhibition of lipid peroxidation, CoQi0 is a very effective antioxidant against the radicals produced in the biological membranes.39 Since the quinol form of the coenzyme Q is present in cell membranes more than the other form, it can be a very efficient antioxidant. Some enzymes such as NADH cytochrome b5 reductase, NADPH coenzyme Q reductase and NADH/NADPH oxidoreductase are effective enzymes which can keep the coenzyme Q reduced in plasma and endomembranes.40

Recent studies show that CoQi0 has numerous other roles including: gene expression modifying, protection of membranes and lipoproteins from protein oxidation and lipid peroxidation, and cell signaling. Therefore, these vital roles led us to its clinical application, especially in energy-demanding tissues involved by the disease, such as heart and liver.41,42 C0Q10 is expressed in all tissues. The body is not normally dependent on exogenous sources of CoQ10, but its biosynthesis is decreased with age and also many critical conditions in which the serum and tissue levels of this coenzyme are reduced by oxidative stress. In such conditions, exogenous CoQi0 is required to maintain the normal blood and tissue levels.43 CoQi0 is absorbed as a lipophilic substance and its uptake increases with high fat food. The main absorption is in the small intestine without any specific receptors. In circulation, CoQi0 is reduced to ubiquinol and then taken up rapidly by the liver where CoQi0 is incorporated mostly into very low-density lipoprotein (VLDL)/low density lipoprotein (LDL) particles. CoQi0 supplements have poor bioavailability in oral administration due to their insolubility in water and high molecular weight.44 CoQi0 metabolism has not been well studied in humans, but studies in animal models suggest that CoQi0 is metabolized in all tissues. The main route of the elimination of CoQi0 is through bile and stool excretion. A small fraction of the metabolites is phosphorylated in the cells, transported to the kidneys through blood, and excreted in the urine.39

Coenzyme Q10 and medical molecular biology

The primary physiological effect of CoQi0 is described as a part of the cellular ATP synthesis system. CoQi0 is a fundamental part of the oxidative phosphorylation of mitochondria. Five protein-lipid complexes situated in the inner mitochondrial membrane, which use molecular oxygen as the final electron acceptor, are engaged in oxidative phosphorylation. Complexes I-IV are responsible for the transportation of electrons to molecular oxygen. CoQi0 is an electron carrier in this process. Finally, this process creates an electrochemical proton-motive force and the final complex (complex V) uses this force to form ATP.45,46 Further studies revealed other molecular properties of CoQi0 as a powerful antioxidant, gene regulator, anti-inflammatory, and immune modulating agent which are discussed as following.

Coenzyme Q10: a powerful antioxidant and antiinflammatory agent

An antioxidant is defined as a substance that inhibits or retards oxidation. CoQ10 is a lipid-soluble antioxidant which acts as a free radical scavenger and a membrane stabilizer, prevents phospholipid peroxidation, and regenerates vitamin E (a-tocopherol) and vitamin C (ascorbate).47 Kagan et al48 postulated that the vitamin E regenerative property of this coenzyme is a more effective pathway to reduce oxidative stress than the free radical scavenging characteristics of CoQ10. The preventive effect of CoQ10 against lipid peroxidation also plays a role as an anti-atherosclerotic property through diminishing the oxidation of LDL.45 CoQ10 also upregulates some enzymatic antioxidants like superoxide dismutase (SOD) and glutathione peroxidase.46 The ubiquinone (oxidized form of CoQ10) become reduced to ubiquinol through the enzymatic actions of NADH-cytochromeb5 reductase and NAD(P)H: quinone oxidoreductase l.49

Researches on human body revealed that the production of CoQ10 reduces through the ages. This contribute to the process of aging and aging related systemic inflammation.8 Inflammation is both the cause and the consequence of oxidative stress. CoQ10 as an immunomodulatory and an antioxidant could rationally act as a strong antiinflammatory agent. Moreover, in clinic, Various metaanalysis on RCTs strongly suggest that CoQ10 significantly reduces TNF-ct, IL-6 and C-reactive protein (CRP).17,50 In another study CoQ10 treatment proves to have a role in reducing the mirl46-a expression which is a regulation factor of inflammatory pathways. Additionally, CoQ10can reduce the further release of IL-6.51 (Figure 3)

Coenzyme Q10: a gene expression regulator

CoQ10 has been identified as a modulator of several biological processes like cell signaling and has a vital role in the mitochondrial respiratory chain and antioxidant activity.52 Moreover, many in vitro and in vivo studies have demonstrated that CoQ10, in addition to its well-known functions, affects the expression of several human genes involved in metabolism, cell signaling, nutrient transport, cell death and cell differentiation.53 Its diverse functions reflect its therapeutic potential as a dietary supplement for a number of diseases such as mitochondrial myopathies, migraine and cardiovascular diseases.54 On the other hand, the conversion of Q10 into its reduced form is accompanied by the generation of reactive oxygen species (ROS) which may also have an additional impact on gene expression.52 A study conducted by Schmelzer et al presented that the reduced form of CoQ10 (Q10H2) has a stronger effect on gene expression than the oxidized form CoQ10, primarily due to differences in bioavailability52 The endogenous insufficiency of CoQ10 synthesis causes the up-regulation of oxidation reactions and the down-regulation of multiple genes which are crucial for growth such as RNA polymerase II. Exogenous CoQ10 supplies partially restore the expression of these genes; however, the expression level of another subset of genes which are involved in some biological functions such as metabolism and cell signaling is not affected by exogenous CoQ10 supplementation and depends solely on endogenous synthesis of CoQ10.55 It has been further demonstrated that CoQ10 supplementation may be effective in regulating the transcription factors contributing to inflammation and fibrosis. Pala et al56 had postulated that CoQ10 supplementation downregulate the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) and upregulate the antiinflammatory pathways trough enhancing inhibitors of kappa B (IkB), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and hemeoxygenase 1 (HO-1). In another study by Mohamed et al57 the downregulating effect of CoQ10 supplementation on transforming growth factor (TGF)-(3l and matrix metalloproteinase (MMP)-9 was indicated. Consistent with the above mentioned animal studies, Armanfar et al58 reported the downregulating effect of CoQ10 supplementation on IL-6, TNF-ct in human subjects.

Coenzyme Q10: an immune-modulating agent

The effect of CoQIO supplementation on the immune system is a complexity of direct and indirect impacts on the energy metabolism, cell signaling and gene expression of the immune cells.59 The role of CoQIO in normal ATP synthesis of mitochondria could considerably prevent the cellular stress and further apoptosis in ATP depleted activated immune cells. It is notable that the majority of immune cells involving in the regulation of the immune response use the mitochondrial pathways for ATP synthesis whereas pro-inflammatory immune cells mostly use the glycolysis pathway for ATP production.60 In view of cell signaling and differentiation of immune cells, studies had demonstrated that CoQIO supplementation reduced the expression of p-STAT3 and further IL-17 while upregulates the expression of p-STAT5 and further FOXP3 which leads to differentiation of CD4 + T cells into regulatory cells rather than the pro-inflammatory T helper 17 cells.61 In one in-vitro study, the peripheral blood mononuclear cells were exposed to CoQi0 for 24 h and the secretion of some cytokines was examined including IL-1(3, IL-1RA, IL-6, IL-10, IL-2, LNF-y, TNF-ct and IL-2. As a result, only TNF-ct and IL-2 secretion was significantly decreased. Notably the outcome of this experiment presented that the treatment with an average concentration of 1.25uM CoQi0 had the best effect, and the higher levels (up to lOuM) did not exert a significant difference.53 The different behavior of C0Q10 in lower and higher dosages is suggestive of a biphasic role for CoQi0. Moreover, in another study by Gollapudi and Gupta, CoQi0 presented an apoptotic protective effect on CD4 + and CD8 + which had been induced with an oxidative stressor. The selected T cells after treatment with CoQi0 (under lOuM concentration) for 24 h showed a strong resistance to an oxidative stress-induced mitochondrial apoptotic pathway. It represented that CoQio could inhibit the activation of both caspase-9 and caspase-3 in apoptotic cascades. Moreover, it can reduce the production of ROS and prevent the oxidative stress-induced mitochondrial membrane depolarization in CD4 + and CD8 + T cells.14 Another critical step in apoptotic process that is also suppressed by CoQio is cytochrome C release from mitochondria according to some experimental studies.62 Furthermore, some studies demonstrated a lowered TNF-ct secretion and a significant declined secretion of MIP-1 a, MCP1 with CoQio treatment on THP-1 cell line, the events which are very important in the COVID-19-induced hyper-inflammatory state. Since the monocytes are able to convert oxidized CoQio into its reduced form, this reduction can be justified. NF-kB is a transcription factor for many genes involved in immune responses including which encode MIP-la, MCP1, and TNF-a. It is believed that down-modulation of these factors is due to NF-kB inhibition. It has not been clearly confirmed that how CoQio effects on NF-kB, but there are some evidences for NF-kB inhibition by antioxidant compounds63,64 (Figure 3).

Coenzyme Q10: an antiviral nutrient

The viral infections, caused by RNA or DNA virus, trigger the production of reactive species (RS) and ROS including: NO, 02-\ OH- and their by-products (such as H202), which interfere with normal functions of the infected cells such as gene expression and metabolism. As an instance, a higher RS level in the host cell promotes the activating of NF-kB which can lead to increased viral replication.65 There are also some evidences that antioxidant agents can mediate viral pathogenesis through the reinforcement of cell resistance against oxidative stress. Moreover, it has been determined that the antioxidant agents exert an important role in decreasing the replication of RNA viruses such as flaviviruses, alphaviruses, and Japanese encephalitis virus through the various pathways in different stages.66 Moreover, a recent molecular docking study of various quinone derivatives demonstrated that CoQIO may indicate direct antiviral properties as CoQIO could effectively binds to the viral protein PDB 6Y84 protease of SARS-COV-2.67

Coenzyme Q10 and anti-angiotensin II properties

The renin-angiotensin system (RAS) has been shown to play a vital role in physiological and pathophysiological events in cardiovascular system. In this cascade, ACE converts AngI to Angll, and Angll as the prime component of RAS, disrupts endothelial function by increasing the oxidative stress. On the other hand, Angll and its receptor induce the activation of NADPH oxidase whereby the synthesis of ROS is increased. When the local levels of ROS are increased, a considerable cellular damage and oxidative stress will occur by interaction with cell membranes, DNA and other molecules.68

Some experimental studies presented that CoQio is involved in enhancing the expression of the antioxidant enzymes and eliminating the free radicals. Treatment with antioxidant agents may remove the misbalance of RAS caused by oxidative stress.69 Moreover, studies demonstrated the preventive effect of CoQ10 against angiotensin induced up-regulation of NADPH oxidase enzyme.70

Clinical implications of coenzyme Q10 in COVID-19

CoQio has been the subject of interest in a variety of diseases including cardiovascular, neurodegenerative, kidney and systemic inflammatory diseases.8 The antioxidant, antiinflammatory, immunomodulatory and gene expression regulator properties of this molecule highlight its application as a considerable choice for nutrient therapy in the aforementioned diseases.47 Some of these conditions such as cardiovascular diseases, hyper-inflammatory state and critical stages of illnesses like septic shock share some features with COVID-19 in pathophysiology. The following statements describe this shared features and possible effects of CoQ10 supplementation in COVID-19 patients.

Coenzyme Q10 and its potential cardioprotective effects

CoQio has a pivotal role in myocyte bioenergetics, exerts anti-inflammatory effects, and reduces oxidative stress. CoQ10 supplementation could be beneficial for a wide spectrum of cardiovascular diseases including: heart failure, hypertension, myocardial infarction, viral myocarditis, arrhythmias, and drug-induced or idiopathic cardiomyopathies.71

The action mechanism of this supplement, according to Greenberg and Ferishman,69 is to not only enhance the cellular aerobic metabolism but also exert cardiovascular effects including: the modification of endothelial dysfunction, preserving the function of the NA+/K+ATPase, stabilizing the cellular membrane, reducing blood viscosity, modulating the immune system, and suppressing systemic inflammation. CoQ10 could be helpful for cardiac patients as a supplement that contribute to increasing mitochondrial phosphate/ oxygen ratio, alleviating reperfusion injury after hypoxic conditions, modifying QRS duration abnormalities, and improve NYHA function class.72 Moreover, CoQ10 improves extracellular SOD and flow-mediated-dilation,72 and protect against progressive left ventricular remodeling and fibrosis.73 Ultimately, CoQ10 can reduce total cardiac events and could be protective against myocardial infraction, congestive heart failure, and dilated and drug-induced types of cardiomyopathies.74

The protective role of CoQ10 in improving viral myocarditis and drug induced cardiotoxicity introduces this supplement as an appropriate choice for the prevention of COVID-19 cardiovascular complications which is generally influenced by two factors: cytokine storm, and adverse effects of the medications.29 The hypercytokinemia caused by SARS-COV-2 infection could lead to fulminant myocarditis,75 a lethal condition mostly caused by hyper-inflammatory state and cytokine storms, particularly during a viral infection.76 Evidence has demonstrated that the blood levels of inflammatory cytokines in critically ill patients in the ICU are higher than the patients not admitted to the ICU; additionally, the level of IL-6 has shown to be higher in patients with cardiac injury75 The anti-inflammatory, antioxidant, and immunomodulatory effects of CoQ10 could suppress the hyper-inflammatory state, particularly through reducing IL-6, TNF-ct and other inflammatory cytokines resulting in the prevention of cardiovascular events in COVID-19 patients and the alleviation of the cardiac complications caused by the cytokine storm in this disease.74,77

Despite the fact that no definitive treatment for COVID-19 has yet been discovered, several curative and supportive medications have been suggested; the most fundamental of which include chloroquine, hydroxyl chloroquine, remdesivir, and potent antibiotics preventing bacterial super infections.78,79 Among the adverse effects of these drugs, particularly hydroxyl chloroquine, cardiovascular complications are of great importance.80 These drugs induce cardiotoxicity through increasing oxidative stress, triggering endothelial dysfunction and elevating tissue inflammation.81 CoQ10 counteracts the cardio-toxic effects of these drugs by improving the mechanism of oxidative phosphorylation, reducing oxidative stress and decreasing the inflammation of the myocardium.82

Coenzyme Q10, primary hypertension and endothelial dysfunction

The pathophysiology of primary hypertension is generally associated with the oxidative stress in the endothelium which leads to decreased available NO for the cells of vascular intima layer, mitochondrial dysfunction of the endothelium, and eventually endothelial dysfunction.83

CoQ10 could improve hypertension through decreasing vascular oxidative stress, improving the function of mitochondria, moderating the effects of Angll, and reducing the level of Aldosterone.71 As mentioned, in the pathophysiology of COVID-19, the RAS system is disturbed due to the interference caused by the protein-protein interaction of the virus spikes and ACE2, leading to the down-regulation of ACE2 which could enhance the pathologic effects of Angll and frustrate the Angll/ Ang ratio resulting in the severe complications of COVID-19 disease.21 Supplementation with Q10 could improve the interference in the RAS system caused by COVID-19 infection through exerting anti-Angll effects and decreasing oxidative stress.70 The antihypertensive effects of CoQ10 are not entirely confirmed and more well-designed clinical trials are suggested to confirm it.84 Studies have demonstrated that CoQ10 could not solely reduce blood pressure but could be beneficial against hypertension in the context of metabolic diseases like diabetes as an adjunctive therapy to adjust blood pressure.82

Coenzyme Q10 in critically ill and ICU patients

The molecular and cellular mechanism of sepsis has not been entirely discovered and includes different aspects. One of the most crucial elements of sepsis is severe oxidative stress accompanied by the mitochondria dysfunction.85

The decreased levels of CoQ10 during septic shock have also a significant importance.86 The elevated levels of IL-6 and IL-8 which have a negative relationship with CoQ10 levels, and the decreased LDL that is the plasma carrier of the coenzyme lead to lower CoQ10 levels during the occurrence of septic shock.87 The coenzyme inversely correlates with vascular endothelial biomarkers like VCAM and inflammatory cytokines like IL-10, and its decrease during septic shock, contributes to the organ failure related to the mitochondrial dysfunction.86

Meanwhile, despite the providing stable and proper hemodynamic conditions along with the optimal oxygenation in the critically ill patients, death rates could not be reduced in these people. This clearly indicates that the substantial mitochondrial dysfunction in the critically ill patients prohibits using the oxygen to produce intracellular ATP even with proper oxygenation.88 CoQ10 could not only counteract the oxidative stress in sepsis as a strong mitochondrial and membranous antioxidant, but could also suppress the production of ROS, increase cellular metabolism and enhance the patients response to oxygenation by alleviating the mitochondrial dysfunction through stabilizing the plasma membrane, sustaining the function of the NA+/K+ATPase, and regulating the oxidative phosphorylation system. Nevertheless, according to evaluations and clinical trials, supplementation with CoQ10 could not solely benefit critically ill patients and it is advised to prescribe CoQ10 with Selenium as a

crucial component of several metabolic enzymes and selenoproteins.11 (Figure 4).

Coenzyme Q10 and its potential neuroprotective effects

Most of neurodegenerative diseases like Alzheimer and Parkinson disease, despite their exclusive neurologic and molecular properties, share some common pathological aspects such as neuro-inflammation, excitotoxicity cascade induced neuronal apoptosis, and mitochondrial dysfunction in affected neurons.89 CoQ10 is a nutrients of interest in adjunctive therapy and the prevention of these types of age related diseases.90 CoQ10 with antiinflammatory, antioxidant and immunomodulatory properties, could suppress the CNS inflammation in such diseases in addition to reducing oxidative stress and enhancing mitochondrial function.91 CoQ10 could also prevent neuronal apoptosis trough keeping mitochondrial permeability transition pores in closed conformation and blocking the apoptosis pathway induced by N-methyl D-aspartate (NMDA) glutamate receptors or non-NMDA glutamate receptors.92

The suggested pathophysiology of neurologic involvement in COVID-19 patient is based on three events; a retrograde trans-synaptic infection of CNS, hematogenous infection of CNS in the context of disrupted BBB due to hypercytokinemia and a systemic inflammation which causes both endothelium and astrocytes dysfunction in BBB, and the direct impact of systemic inflammation and oxidative stress on CNS and PNS causing neuronal damage and pathologic reactions in the supportive tissue of neurologic system, blood vessels, coagulation cascades and endothelium resulting in the cerebrovascular accidents.30,32

CoQ10 as a lipophilic antioxidant which passes easily through BBB, has a direct effect on reducing oxidative stress and modulating the immunologic reactions, which could be beneficial through suppressing the systemic inflammation,90 preventing BBB damage,93 and neuronal apoptosis in COVID-19 patients.92 Accordingly, CoQ10 supplementation could prevent the developing CNS and PNS damage and further deleterious consequences like central respiratory failure, delirium and loss of conciseness, leading to a permanent brain injury and death31 (Figure 1).

Conclusion

COVID-19 as a pandemic lethal infection, currently, has no definite treatment. The interaction of virus-spike with ACE2 receptor leads to the down-regulation of ACE2 which could enhance the pathologic effects of Angll and disturb the AngII/Ang(1 _ ratio. It could result in a huge cytokine storm, and an extensive oxidative stress which are the molecular basis of the most complications induced by COVID-19. CoQ10 as an essential electron transporter in the phosphorylative oxidation system is a powerful lipophilic antioxidant, anti-apoptotic, immunomodulatory and anti-inflammatory supplement which has been tested for the management and prevention of a variety of diseases specially diseases with inflammatory pathogenesis. CoQ10 can decrease the important inflammatory cytokines and prevent the organ damages due to a huge oxidative stress. CoQ10 can be also a cardio-protective and neuroprotective agent through reducing the viral toxicity against cardiomyocytes and CNC neurons. Accordingly, CoQ10 supplementation could prevent the COVID-19-induced morbidities and has a potential protective role against the deleterious consequences of the disease. Competing Interests All authors declare no conflict of interest. Ethical Approval Not applicable.

References

References 1. Cascella M, Rajnik M, Cuomo A, Dulebohn SC, Di Napoli R. Features, evaluation, and treatment of coronavirus (COVID-19). In: StatPearls. Treasure Island, FL: StatPearls Publishing; 2021.

2. Fehr AR, Perlman S. Coronaviruses: an overview of their replication and pathogenesis. Methods Mol Biol201 5;1282:1 -23. doi: 1 0.1 007/978-1-4939-2438-7J

3. Phan MVT, Ngo Tri T, Hong Anh P, Baker S, Kellam P, Cotten M. Identification and characterization of Coronaviridae genomes from Vietnamese bats and rats based on conserved protein domains. Virus Evol 201 8;4(2):vey035. doi: 10.1093/ ve/vey035

4. Li F. Structure, function, and evolution of coronavirus spike proteins. Annu Rev Virol 2016;3(1):237-61. doi: 10.1146/ annurev-virology-11 061 5-042301

5. Hamming I, Timens W, Bulthuis ML, Lely AT, Navis C, van Coor H. Tissue distribution of ACE2 protein, the functiona receptor for SARS coronavirus. A first step in understanding SARS pathogenesis. / Pathol2004;203(2):631 -7. doi: 1 0.1 002/ path.1570

6. Ni W, Yang X, Yang D, Bao J, Li R, Xiao Y, et al. Role of angiotensin-converting enzyme 2 (ACE2) in COVID-19. Crit Care 2020;24(1 ):422. doi: 1 0.11 86/s1 3054-020-031 20-0

7. CraneFL.BiochemicalfunctionsofcoenzymeQI O.JAmCollNutr 2001 ;20(6):591 -8. doi: 1 0.1 080/0731 5724.2001.1 071 9063

8. Hernandez-Camacho JD, BernierM, Lopez-Lluch C, Navas P. Coenzyme Q10 supplementation in aging and disease. Front Physiol201 8;9:44. doi: 1 0.3389/fphys.201 8.00044

9. Jafari M, Mousavi SM, Asgharzadeh A, Yazdani N. Coenzyme Q1 0 in the treatment of heart failure: a systematic review of systematic reviews. Indian Heart) 201 8;70(Suppl 1 ):S111-S7. doi: 10.1 01 6/j.ihj.201 8.01.031

10. Fan L, Feng Y, Chen CC, Qin LQ, Fu CL, Chen LH. Effects of coenzyme Q10 supplementation on inflammatory markers: a systematic review and meta-analysis of randomized controlled trials. Pharmacol Res 2017;119:128-36. doi: 10.1016/j. phrs.201 7.01.032

11. Hargreaves IP, Mantle D. Supplementation with selenium and coenzyme Q1 0 in critically ill patients. Br) Hosp Med (Lond) 201 9;80(1 0):589-93. doi: 1 0.1 2968/hmed.201 9.80.1 0.589

12. Schmelzer C, Lorenz C, Lindner I, Rimbach C, Niklowitz P, Menke T, et al. Effects of coenzyme Q10 on TNF-alpha secretion in human and murine monocytic cell lines. Biofactors 2007;31 (1 ):35-41. doi: 1 0.1 002/biof.552031 01 04

13. Schmelzer C, Lorenz C, Rimbach C, Doring F. Influence of coenzyme Q1 0 on release of pro-inflammatory chemokines in the human monocytic cell line THP-1. Biofactors 2007;31(3-4):211 -7. doi: 1 0.1 002/biof.552031 0308

14. Collapudi S, Gupta S. Reversal of oxidative stress-induced apoptosis in T and B lymphocytes by coenzyme Q1 0 (CoQ1 0). Am j Clin Exp Immunol 201 6;5(2):41 -7.

15. Kishimoto C, Tomioka N, Nakayama Y, Miyamoto M. Antioxidant effects of coenzyme Q10 on experimental vira myocarditis in mice./ Cardiovasc Pharmacol2003;42(5):588-92. doi: 10.1097/00005344-200311000-00002

1 6. Kelekgi S, Evliyaoglu O, Sen V, Yolba? I, Uluca U, Tan I, et al. The relationships between clinical outcome and the levels of

total antioxidant capacity (TAC) and coenzyme Q (CoQ 1 0) in children with pandemic influenza (H 1 N1) and seasonal flu. Eur Rev Med Pharmacol Sci 201 2;1 6(8):1 033-8.

17. Chase M, Cocchi MN, Liu X, Andersen LW, Holmberg MJ, Donnino MW. Coenzyme Q10 in acute influenza. Influenza Other Respir Viruses 2019;13(1):64-70. doi: 10.1111/ irv. 12608

18. Polymeropoulos V. A potential role of coenzyme Q10 deficiency in severe SARS-CoV2 infection. OBM Integrative and Complementary Medicine 2020;5(4):042. doi: 1 0.21 926/ obm.icm .2004042

19. Pagano C, Manfredi C, Pallardo FV, Lyakhovich A, Tiano L, Trifuoggi M. Potential roles of mitochondrial cofactors in the adjuvant mitigation of proinflammatory acute infections, as in the case of sepsis and COVID-19 pneumonia. Inflamm Res 2021 ;70(2):1 59-70. doi: 1 0.1 007/s00011 -020-01 423-0

20. Hanff TC, Harhay MO, Brown TS, Cohen JB, Mohareb AM. Is there an association between COVID-19 mortality and the renin-angiotensin system? A call for epidemiologic investigations. Clin Infect Dis 2020;71 (15):870-4. doi: 10.1093/cid/ciaa329 21. Cheng H, Wang Y, Wang CQ. Organ-protective effect of angiotensin-converting enzyme 2 and its effect on the prognosis of COVID-1 9. / Med Virol 2020;92(7):726-30. doi: 10.1002/jmv.25785 22. Simoes e Silva AC, Silveira KD, Ferreira AJ,Teixeira MM. ACE2, angiotensin-(1-7) and Mas receptor axis in inflammation and fibrosis. Br 1 Pharmacol 201 3;1 69(3):477-92. doi: 10.1111/ bph.12159 23. Wang L, Hu X, Zhang W, Tian F. Angiotensin (1 -7) ameliorates angiotensin ll-induced inflammation by inhibiting LOX-1 expression. Inflamm Res 2013;62(2):219-28. doi: 10.1007/ s00011-012-0571-2

24. Mehta P, McAuley DF, Brown M, Sanchez E, Tattersall RS, Manson JJ. COVID-19: consider cytokine storm syndromes and immunosuppression. Lancet 2020;395(1 0229):1 033-4. doi: 10.1 01 6/s0140-6736(20)30628-0

25. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet 2020;395(10223):497-506. doi: 1 0.1 01 6/s0140-6736(20)301 83-5

26. Diao B, Wang C, Tan Y, Chen X, Liu Y, Ning L, et al. Reduction and functional exhaustion oft cells in patients with coronavirus disease 2019 (COVID-19). medRxiv [Preprint]. February 20, 2020. Available from: https://www.medrxiv.org/ content/1 0.11 01/2020.02.1 8.20024364v1.

27. Wesche DE, Lomas-Neira JL, Perl M, Chung CS, Ayala A. Leukocyte apoptosis and its significance in sepsis and shock. / Leukoc Biol2005;78(2):325-3 7. doi: 1 0.11 89/jlb.01 0501 7

28. Zhang W, Zhao Y, Zhang F, Wang Q, Li T, Liu Z, et al. The use of anti-inflammatory drugs in the treatment of people with severe coronavirus disease 201 9 (COVID-1 9): the perspectives of clinical immunologists from China. Clin Immunol 2020;21 4:1 08393. doi: 1 0.1 01 6/j.clim.2020.1 08393

29. Fakhrolmobasheri M, Khanahmad H, Kahlani MJ, Shiravi AA, Shahrokh SC, Zeinalian M. L-carnitine can extinguish the COVID-19 fire: a review on molecular aspects. Authorea. 2022. doi: 1 0.22541/au.1 65279258.8439361 8/v1

30. Steardo L, Steardo LJr, Zorec R, Verkhratsky A. Neuroinfection may contribute to pathophysiology and clinical manifestations of COVID-19. Acta Physiol (Oxf) 2020;229(3):e1 3473. doi: 1 0.1111/apha.13473

31. Mao L, Wang M, Chen S, He Q, Chang J, Hong C, et al. Neurological manifestations of hospitalized patients with COVID-1 9 in Wuhan, China: a retrospective case series study. medRxiv [Preprint]. February 25, 2020. Available from: https:// www.medrxiv.org/content/10.1101/2020.02.22.20026500v1.

32. Beckman Danielle, Bonillas Alyssa, Diniz Ciovanne B, Ott Sean, Roh Jamin W, Elizaldi Sonny R, et al. SARS-CoV-2 infects neurons and induces neuroinflammation in a non-human primate model of COVID-19. Cell Rep 2022;41 (5):111 573. doi: 1 0.1 01 6/j.celrep.2022.111 573.

33. Li YC, Bai WZ, Hashikawa T. The neuroinvasive potential of SARS-CoV2 may play a role in the respiratory failure of COVID-19 patients. / Med Virol 2020;92(6):552-5. doi: 10.1002/jmv.25728

34. Crane FL, Hatefi Y, Lester RL, Widmer C. Isolation of a quinone from beef heart mitochondria. Biochim Biophys Acta 1 957;25(1):220-1. doi: 1 0.1 01 6/0006-3002(57)90457-2

35. BankC, Kagan D, Madhavi D. Coenzyme Q1 0: clinical update and bioavailability. / Evid Based Complementary Altern Med 2011;16(2):1 29-37. doi: 10.1177/2156587211399438

36. Hodgson JM, Watts CF. Can coenzyme Q1 0 improve vascular function and blood pressure? Potential for effective therapeutic reduction in vascular oxidative stress. Biofactors 2003;18(1-4):1 29-36. doi: 1 0.1 002/biof.55201 8021 5

3 7. Yang YK, Wang LP, Chen L, Yao XP, Yang KQ, Cao LC, et al. Coenzyme Q1 0 treatment of cardiovascular disorders of ageing including heart failure, hypertension and endothelia dysfunction. Clin Chim Acta 2015;450:83-9. doi: 10.1016/j. cca.201 5.08.002

38. Hargreaves IP. Coenzyme Q1 0 as a therapy for mitochondria disease. Int ) Biochem Cell Biol 2014;49:105-11. doi: 10.1 01 6/j.biocel.2014.01.020

39. Bhagavan HN, Chopra RK. Coenzyme Q1 0: absorption, tissue uptake, metabolism and pharmacokinetics. Free Radic Res 2006;40(5):445-53. doi: 1 0.1 080/1 071 576060061 7843

40. Folkers K, Wolaniuk A. Research on coenzyme Q1 0 in clinica medicine and in immunomodulation. Drugs Exp Clin Res 1985;11(8):539-45.

41. Carrido-Maraver J, Cordero MD, Oropesa-Avila M, Fernandez Vega A, de la Mata M, Delgado Pavon A, et al. Coenzyme q10 therapy. Mol Syndromol 2014;5(3-4):187-97. doi: 10.1159/000360101

42. Mohammed-Jawad NK, Al-Sabbagh M, Al-Jezaeri KA. Role of L-carnitine and coenzyme Q10 as adjuvant therapy in patients with type 2 diabetes mellitus. Am ) Pharmacol Sci 2014;2(5):82-6. doi: 1 0.12691/ajps-2-5-2

43. NegidaA, Menshawy A, El Ashal C, ElfoulyY, HaniY, Hegazy Y, et al. Coenzyme Q1 0 for patients with parkinson's disease: a systematic review and meta-analysis. CNS Neurol Disord Drug Targets 201 6; 1 5(1):45-53. doi: 10.2174/187152 731466 6150821103306

44. Pravst I, Rodrfguez Aguilera JC, Cortes Rodriguez AB, Jazbar J, Locatelli I, Hristov H, et al. Comparative bioavailability of different coenzyme Q10 formulations in healthy elderly individuals. Nutrients 2020;12(3):784. doi: 10.3390/ nu12030784

45. Thomas SR, Neuzil J, Stacker R. Inhibition of LDL oxidation by ubiquinol-1 0. A protective mechanism for coenzyme Q in atherogenesis? Mol Aspects Med 1 997;1 8 Suppl:S85-1 03. doi: 1 0.1 01 6/s0098-2997(97)00031 -9

46. BlattT, Littarru CP. Biochemical rationale and experiments data on the antiaging properties of CoQ10 at skin level. Biofactors 2011 ;37(5):381 -5. doi: 1 0.1 002/biof.1 69

47. Barcelos IP, Haas RH. CoQ10 and aging. Biology (Basel) 201 9;8(2):28. doi: 1 0.3390/biology8020028

48. Kagan V, Serbinova E, Packer L. Antioxidant effects of ubiquinones in microsomes and mitochondria are mediated by tocopherol recycling. Biochem Biophys Res Commun 1 990;1 69(3):851 -7. doi: 1 0.1 01 6/0006-291 x(90)91 971 -t

49. Navas P, Villalba JM, Lenaz C. Coenzyme Q-dependent functions of plasma membrane in the aging process. Age (Dordr) 2005;27(2):1 39-46. doi: 1 0.1 007/s11 357-005-1 632-z

50. Schmelzer C, Lindner I, Rimbach C, Niklowitz P, Menke T, Doring F. Functions of coenzyme Q10 in inflammation and gene expression. Biofactors 2008;32(1-4):1 79-83. doi: 10.1002/biof.5520320121

51. Olivieri F, Lazzarini R, Babini L, Prattichizzo F, Rippo MR, Tiano L, et al. Anti-inflammatory effect of ubiquinol-10 on young and senescent endothelial cells via miR-146a modulation. Free Radic Biol Med 2013;63:410-20. doi: 1 0.1 01 6/j.freeradbiomed.201 3.05.033

52. Schmelzer C, Kubo H, Mori M, Sawashita J, Kitano M, Hosoe K, et al. Supplementation with the reduced form of coenzyme Q1 0 decelerates phenotypic characteristics of senescence and induces a peroxisome proliferator-activated receptor-alpha gene expression signature in SAMP1 mice. Mol Nutr Food Res 201 0;54(6):805-1 5. doi: 1 0.1 002/mnfr.2009001 55

53. Bessler H, Bergman M, Blumberger N, Djaldetti M, Salman H. Coenzyme Q10 decreases TNF-alpha and IL-2 secretion by human peripheral blood mononuclear cells. / Nutr Sci Vitaminol (Tokyo) 201 0;56(1):77-81. doi: 1 0.31 77/jnsv.56.77

54. Schmelzer C, Lindner I, Vock C, Fujii K, Doring F. Functiona connections and pathways of coenzyme Q10-inducible genes: an in-silico study. IUBMB Life 2007;59(10):628-33. doi: 10.1080/15216540701545991

55. Fischer A, Niklowitz P, Menke T, Doring F. Promotion of growth by coenzyme Q10 is linked to gene expression in C elegans. Biochem Biophys Res Commun 201 4;452(4):920-7. doi: 1 0.1 01 6/j.bbrc.201 4.09.01 6

56. Pala R, Orhan C, Tuzcu M, Sahin N, Ali S, Cinar V, et al. Coenzyme Q10 supplementation modulates NFkB and Nrf2 pathways in exercise training.) Sports Sci Med 201 6;1 5(1 ):1 96-203.

57. Mohamed HA, Said RS. Coenzyme Q10 attenuates inflammation and fibrosis implicated in radiation enteropathy through suppression of NF-kB/TCF-(3/MMP-9 pathways. Int Immunopharmacol 2021 ;92:107347. doi: 10.1016/j. intimp.2020.1 07347

58. Armanfar M, Jafari A, Dehghan CR, Abdizadeh L. Effect of coenzyme Q10 supplementation on exercise-induced response of inflammatory indicators and blood lactate in male runners. Med) Islam Repub Iran 201 5;29:202.

59. Mantle D, Heaton RA, Hargreaves IP. Coenzyme Q10 and immune function: an overview. Antioxidants (Basel) 2021 ;1 0(5):759. doi: 1 0.3390/antiox1 0050759

60. Faas MM, de Vos P. Mitochondrial function in immune cells in health and disease. Biochim Biophys Acta Mol Basis Dis 2020;1 866(1 0):1 65845. doi: 1 0.1 01 6/j.bbadis.2020.1 65845

61. Lee SY, Lee SH, Yang EJ, Kim JK, Kim EK, Jung K, et al. Coenzyme Q10 inhibits Th1 7 and STAT3 signaling pathways to ameliorate colitis in mice. / Med Food 201 7;20(9):821 -9. doi: 1 0.1 089/jmf.201 6.3859

62. Sumi K, OkuraT, FujiokaY, Kato M, ImamuraT, Taniguchi SI, et al. Coenzyme Q10 suppresses apoptosis of mouse pancreatic P-cell line MIN6. Diabetol Metab Syndr 201 8;10:47. doi: 1 0.1186/s1 3098-01 8-0351 -4

63. Zhang Y, Wang Z, Chen H, Chen Z, Tian Y. Antioxidants: potential antiviral agents for Japanese encephalitis virus infection. Int ) Infect Dis 2014;24:30-6. doi: 10.1016/j. ijid.201 4.02.011

64. Camini FC, da Silva Caetano CC, Almeida LT, de Brito Magalhaes CL. Implications of oxidative stress on vira pathogenesis. Arch Virol 201 7;1 62(4):907-1 7. doi: 10.1007/ s00705-016-3187-y

65. Schwarz KB. Oxidative stress during viral infection: a review. Free Radic Biol Med 1 996;21 (5):641-9. doi: 1 0.1 01 6/0891 -5849(96)00131-1

66. Roncati L, Callo C, Manenti A, Palmieri B. Renin-angiotensin system: the unexpected flaw inside the human immune system

revealed by SARS-CoV-2. Med Hypotheses 2020;140:1 09686. cloi: 1 0.1 01 6/j.mehy.2020.1 09686

67. Caruso F, Rossi M, Pedersen JZ, Incerpi S. Computationa studies reveal mechanism by which quinone derivatives can inhibit SARS-CoV-2. Study of embelin and two therapeutic compounds of interest, methyl prednisolone and dexamethasone. / Infect Public Health 2020;1 3(12):1 868-77. doi: 10.1016/j.jiph.2020.09.015

68. El Assar M, Angulo J, Rodrfguez-Mahas L. Oxidative stress and vascular inflammation in aging. Free Radic Biol Med 201 3;65:380-401. doi: 1 0.1 01 6/j.freeradbiomed.201 3.07.003

69. Creenberg S, Frishman WH. Co-enzyme Q1 0: a new drug for cardiovascular disease. / Clin Pharmacol 1 990;30(7):596-608. doi: 1 0.1 002/J.1 552-4604.1 990.tb01 862.x

70. Tsuneki H, Tokai E, Suzuki T, Seki T, Okubo K, Wada T, et al. Protective effects of coenzyme Q1 0 against angiotensin II-induced oxidative stress in human umbilical vein endothelia cells. Eur J Pharmacol 201 3;701 (1 -3):21 8-27. doi: 10.1016/j. ejphar.2012.12.027

71. Zozina VI, Covantev S, Coroshko OA, Krasnykh LM, Kukes VC. Coenzyme Q1 0 in cardiovascular and metabolic diseases: current state of the problem. Curr Cardiol Rev 201 8;14(3):1 64-74. doi: 10.2174/1573403x14666180416115428

72. Littarru CP, Tiano L. Clinical aspects of coenzyme Q10: an update. Nutrition 2010;26(3):250-4. doi: 10.1016/j. nut.2009.08.008

73. Singh RB, Fedacko J, Mojto V, Pella D. Coenzyme Q10 modulates remodeling possibly by decreasing angiotensin-converting enzyme in patients with acute coronary syndrome. Antioxidants (Basel) 201 8;7(8):99. doi: 10.3390/ antiox7080099

74. Sarter B. Coenzyme Q1 0 and cardiovascular disease: a review. / Cardiovasc Nurs 2002;1 6(4):9-20. doi: 10.1097/00005082-200207000-00003

75. Chen C, Zhou Y, Wang DW. SARS-CoV-2: a potential novel etiology of fulminant myocarditis. Herz 2020;45(3):230-2. doi: 1 0.1 007/s00059-020-04909-z

76. Cooper LTJr. Myocarditis. N Engl J Med 2009;360(1 5):1 526-38. doi: 10.1056/NEJMra0800028

77. LiuT, Zhang L, Joo D, Sun SC. NF-kB signaling in inflammation. Signal Transduct Target Ther 201 7;2:1 7023. doi: 10.1038/ sigtrans.201 7.23

78. Zhang L, Liu Y. Potential interventions for novel coronavirus in China: a systematic review, j Med V/ro/2020;92(5):479-90. doi: 10.1002/jmv.25707

79. Beigel JH, Tomashek KM, Dodd LE, Mehta AK, Zingman BS, Kalil AC, et al. Remdesivir for the treatment of COVID-19 - final report. N Engl J Med 2020;383(19):1813-26. doi: 10.1056/NEJMoa2007764

80. Mladenka P, Applova L, PatockaJ, CostaVM, Remiao F, Pourova J, et al. Comprehensive review of cardiovascular toxicity of

drugs and related agents. Med Res Rev 201 8;38(4):1 332-403. doi: 1 0.1 002/med.21476

81. Tonnesmann E, Kandolf R, Lewalter T. Chloroquine cardiomyopathy-a review of the literature. Immunopharmacol Immunotoxicol 201 3;35(3):434-42. doi: 1 0.31 09/08923973.201 3.780078

82. Langsjoen P, Langsjoen P, Willis R, Folkers K. Treatment of essential hypertension with coenzyme Q1 0. MolAspects Med 1994;15 Suppl:S265-72. doi: 10.1016/0098-2997(94)90037-X

83. Dinh QN, Drummond CR, Sobey CC, Chrissobolis S. Roles of inflammation, oxidative stress, and vascular dysfunction in hypertension. Biomed Res Int 2014;2014:406960. doi: 10.1155/2014/406960

84. Ho MJ, Li EC, Wright JM. Blood pressure lowering efficacy of coenzyme Q1 0 for primary hypertension. Cochrane Database Syst Rev 2016;3(3):CD007435. doi: 10.1002/14651858. CD007435.pub3

85. Mantzarlis K, Tsolaki V, Zakynthinos E. Role of oxidative stress and mitochondrial dysfunction in sepsis and potentia therapies. Oxid Med Cell Longev 201 7;201 7:5985209. doi: 10.1155/2017/5985209

86. Donnino MW, Cocchi MN, Salciccioli JD, Kim D, Naini AB, Buettner C, et al. Coenzyme Q1 0 levels are low and may be associated with the inflammatory cascade in septic shock. Crit Care 2011 ;1 5(4):R1 89. doi: 1 0.11 86/cc1 0343

87. Cocchi MN, Ciberson B, Berg K, Salciccioli JD, Naini A, Buettner C, et al. Coenzyme Q10 levels are low and associated with increased mortality in post-cardiac arrest patients. Resuscitation 2012;83(8):991-5. doi: 10.1016/j. resuscitation.201 2.03.023

88. Cattinoni L, Brazzi L, Pelosi P, Latini R, Tognoni C, Pesenti A, et al. A trial of goal-oriented hemodynamic therapy in critically ill patients. Sv02 Collaborative Croup. N Engl) Med 1 995;333(1 6):1 025-32. doi: 1 0.1 056/nejm1 9951 01 93331 601

89. Relja M. Pathophysiology and classification of neurodegenerative diseases. EJIFCC 2004;1 5(3):97-9.

90. Calpern WR, Cudkowicz ME. Coenzyme Q treatment of neurodegenerative diseases of aging. Mitochondrion 2007;7 Suppl:S146-53. doi: 1 0.1 01 6/j.mito.2007.01.004

91. Beal MR Coenzyme Q10 administration and its potential for treatment of neurodegenerative diseases. Biofactors 1 999;9(2-4):261 -6. doi: 1 0.1 002/biof.5520090222

92. Martucci A, Nucci C. Evidence on neuroprotective properties of coenzyme Q1 0 in the treatment of glaucoma. Neural Regen Res 201 9;14(2):1 97-200. doi: 1 0.41 03/1 673-5374.244781

93. Kaisar MA, Prasad S, Cucullo L. Protecting the BBB endothelium against cigarette smoke-induced oxidative stress using popular antioxidants: are they really beneficial? Brain Res 201 5;1 627:90-1 00. doi: 1 0.1 01 6/j.brainres.201 5.09.01 8