Glucose-6-phosphate dehydrogenase inhibitor for treatment of severe COVID-19: Polydatin

Exploring Bioactive Phytomedicines for Advancing Pulmonary Infection Management: Insights and Future Prospects

Pulmonary infections have a profound influence on global mortality rates. Medicinal plants offer a promising approach to address this challenge, providing nontoxic alternatives with higher levels of public acceptance and compliance, particularly in regions where access to conventional medications or diagnostic resources may be limited. Understanding the pathophysiology of viruses and bacteria enables researchers to identify biomarkers essential for triggering diseases. This knowledge allows the discovery of biological molecules capable of either preventing or alleviating symptoms associated with these infections. In this review, medicinal plants that have an effect on COVID-19, influenza A, bacterial and viral pneumonia, and tuberculosis are discussed. Drug delivery has been briefly discussed as well. It examines the effect of bioactive constituents of these plants and synthesizes findings from in vitro, in vivo, and clinical studies conducted over the past decade. In conclusion, many medicinal plants can be used to treat pulmonary infections, but further in-depth studies are needed as most of the current studies are only at preliminary stages. Extensive investigation and clinical studies are warranted to fully elucidate their mechanisms of action and optimize their use in clinical practice.

Butyrate induces oxidative burst mediated apoptosis via Glucose-6-Phosphate Dehydrogenase (G6PDH) in macrophages during mycobacterial infection

Microorganisms present in the gut modulate host defence responses against infections in order to maintain immune homeostasis. This host-microbe crosstalk is regulated by gut metabolites. Butyrate is one such small chain fatty acid produced by gut microbes upon fermentation that has the potential to influence immune responses. Here we investigated the role of butyrate in macrophages during mycobacterial infection. Results demonstrate that butyrate significantly suppresses the growth kinetics of mycobacteria in culture medium as well as inhibits mycobacterial survival inside macrophages. Interestingly, butyrate alters the pentose phosphate pathway by inducing higher expression of Glucose-6-Phosphate Dehydrogenase (G6PDH) resulting in a higher oxidative burst via decreased Sod-2 and increased Nox-2 (NADPH oxidase-2) expression. Butyrate-induced G6PDH also mediated a decrease in mitochondrial membrane potential. This in turn lead to an induction of apoptosis as measured by lower expression of the anti-apoptotic protein Bcl-2 and a higher release of Cytochrome C as a result of induction of apoptosis. These results indicate that butyrate alters the metabolic status of macrophages and induces protective immune responses against mycobacterial infection.

Severity of oxidative stress as a hallmark in COVID-19 patients

INTRODUCTION

Understanding the mechanisms and identifying effective treatments for the COVID-19 outbreak are imperative. Therefore, this study aimed to assess the antioxidant status and oxidative stress parameters as potential pivotal mechanisms in asymptomatic, non-severe, and severe COVID-19 patients.

METHODS

This study is a case-control study that was performed on patients referred to the Persian Gulf Martyrs Hospital of Bushehr University of Medical Sciences, Bushehr, Iran, from May 2021 to September 2021. A total of 600 COVID-19 patients (non-severe and severe group) and 150 healthy volunteers of the same age and sex were selected during the same period. On the first day of hospitalization, 10 ml of venous blood was taken from subjects. Then, hematological, biochemical, serological, antioxidant and oxidative stress parameters were determined.

RESULTS

Our results indicated that ESR, CRP, AST, ALT, and LDH significantly augmented in the severe group as compared to the non-severe and normal groups (P ≤ 0.05). It was observed that the levels of FRAP, G6PD activity, and SOD activity significantly reduced in the non-severe patients in comparison with the severe and normal groups (P ≤ 0.05). We found that MDA content and NO metabolite markedly increased in severe patients as compared to the non-severe group.

CONCLUSIONS

Taken together, it seems that the balance between antioxidants and oxidants was disturbed in COVID-19 patients in favor of oxidant markers. In addition, this situation caused more aggravation in severe patients as compared to the non-severe group.

Glucose-6-phosphate dehydrogenase: a therapeutic target for ovarian cancer

INTRODUCTION

Ovarian cancer (OC) is a gynecological tumor disease, which is usually diagnosed at an advanced stage and has a poor prognosis. It has been established that the glucose metabolism rate of cancer cells is significantly higher than that of normal cells, and the pentose phosphate pathway (PPP) is an important branch pathway for glucose metabolism. Glucose-6-phosphate dehydrogenase (G6PD) is the key rate-limiting enzyme in the PPP, which plays an important role in the initiation and development of cancer (such as OC), and has been considered as a promisinganti-cancer target.

AREAS COVERED

In this review, based on the structure and biological function of G6PD, recent research on the roles of G6PD in the progression, metastasis, and chemoresistance of OC are summarized and accompanied by proposed molecular mechanisms, which may provide a systematic understanding of targeting G6PD for the treatment of patients with OC.

EXPERT OPINION

Accumulating evidence demonstrates that G6PD is a promising target of cancer. The development of G6PD inhibitors for cancer treatment merits broad application prospects.

G6PD deficiency-does it alter the course of COVID-19 infections?

Despite the existence of well-founded data around the relationship between reactive oxygen species (ROS) and glucose-6-phosphate dehydrogenase (G6PD), current research around G6PD-deficient patients with viral infections, and limitations as a result of their condition, are inadequate. Here, we analyze existing data around immunological risks, complications, and consequences of this disease, particularly in relation to COVID-19 infections and treatment. The relationship between G6PD deficiency and elevated ROS leading to increased viral load suggests that these patients may confer heightened infectivity. Additionally, worsened prognoses and more severe complications of infection may be realized in class I G6PD-deficient individuals. Though more research is demanded on the topic, preliminary studies suggest that antioxidative therapy which reduces ROS levels in these patients could prove beneficial in the treatment of viral infections in G6PD-deficient individuals.

Polydatin attenuates tubulointerstitial fibrosis in diabetic kidney disease by inhibiting YAP expression and nuclear translocation

The activation of Yes-associated protein (YAP) pathway is mutually causal with the increase of extracellular matrix (ECM) stiffness. Polydatin (PD) has been proved to have anti-fibrosis effect in diabetic kidney disease (DKD), but it is still a mystery whether PD participates in YAP-related mechano-transduction. Therefore, this study intends to solve the following two problems: 1) To construct an in vitro system of polyacrylamide hydrogels (PA gels) based on the true stiffness of kidneys in healthy and DKD rats, and observe the effect of PD on pathological matrix stiffness-induced YAP expression in renal fibroblasts; 2) Compared with verteporfin (VP), a pharmacological inhibitor of YAP, to explore whether the therapeutic effect of PD on DKD in vivo model is related to the regulation of YAP. In this study, the in vitro system of PA gels with 3 kPa, 12 kPa and 30 kPa stiffness was constructed and determined for the first time to simulate the kidney stiffness of healthy rats, rats with DKD for 8 weeks and 16 weeks, respectively. Compared with the PA gels with 3 kPa stiffness, the PA gels with 12 kPa and 30 kPa stiffness significantly increased the expression of YAP, α-smooth muscle actin (α-SMA) and collagen I, and the production of reactive oxygen species (ROS) in renal fibroblasts, and the PA gels with 30 kPa stiffness were the highest. PD significantly inhibited the above-mentioned changes of fibroblasts induced by pathological matrix stiffness, suggesting that the inhibition of PD on fibroblast-to-myofibroblast transformation and ECM production was at least partially associated with regulating YAP-related mechano-transduction pathway. Importantly, the inhibitory effect of PD on YAP expression and nuclear translocation in kidneys of DKD rats is similar to that of VP, but PD is superior to VP in reducing urinary protein, blood glucose, blood urea nitrogen and serum creatinine, as well as decreasing the expression of α-SMA and collagen I, ROS overproduction and renal fibrosis. Our results prove for the first time from the biomechanical point of view that PD is a potential therapeutic strategy for delaying the progression of renal fibrosis by inhibiting YAP expression and nuclear translocation.

Polydatin Attenuates Cisplatin-Induced Acute Kidney Injury via SIRT6-Mediated Autophagy Activation

In the treatment of malignant tumors, the effectiveness of cisplatin (CP) is limited by its nephrotoxicity, leading to cisplatin-induced acute kidney injury (CP-AKI). Polydatin (PD) has been demonstrated to regulate autophagy in tumors, sepsis, and diabetes. We have recently confirmed that PD attenuated CP-AKI by inhibiting ferroptosis, but it is not clear whether PD can regulate autophagy to protect from CP-AKI. The purpose of this study was to investigate the effect of PD on autophagy in CP-treated HK-2 cells and CP-AKI mouse models, exploring the role of sirtuin 6 (SIRT6) upregulated by PD. In this study, the blocking of autophagy flux was observed in both CP-treated HK-2 cells in vitro and CP-AKI mouse models in vivo, whereas this blocking was reversed by PD, which was characterized by the increase of autophagy microtubule-associated protein light chain 3 II expression and autophagolysosome/autophagosome ratio and the decrease of p62 expression. Furthermore, PD also significantly increased the expression of SIRT6 in vivo and in vitro. The protective effect of PD manifested by the stimulating of autophagy flux, with the reducing of inflammatory response and oxidative stress, which included downregulation of tumor necrosis factor-α and interleukin-1β, decreased activity of myeloperoxidase and content of malondialdehyde, and increased activity of superoxide dismutase and level of glutathione, both in vivo and in vitro, was reversed by either inhibition of autophagy flux by chloroquine or downregulation of SIRT6 by OSS-128167. Taken together, the present findings provide the first evidence demonstrating that PD exhibited nephroprotective effects on CP-AKI by restoring SIRT6-mediated autophagy flux mechanisms.

Herbal Sources of Magnesium as a Promising Multifaceted Intervention for the Management of COVID-19

The coronavirus-disease 2019 (COVID-19) was announced as a global pandemic by the World Health Organization (WHO), and it affected all human groups. Severe COVID-19 is characterized by cytokine storms, which can lead to multiorgan failure and death, although fever and cough are the most typical symptoms of mild COVID-19. Plant-based diets provide a 73% lower risk of moderate-to-severe COVID-19. Additionally, the association between low levels of some micronutrients and the adverse clinical consequences of COVID-19 has been demonstrated. So, nutritional therapy can become part of patient care for the survival of this life-threatening disease (COVID-19) also short-term recovery. Magnesium as an essential micronutrient due to its anti-inflammatory and beneficial effects can effectively prevent COVID-19 pandemic by playing a role in the treatment of comorbidities such as diabetes and cardiovascular disorders as major risk factors for mortality. Sufficient magnesium to stay healthy is provided by a proper daily diet, and there is usually no need to take magnesium supplements. Considering that almost half of the dietary magnesium comes from fruits, vegetables, nuts, and grains, it seems necessary to pay attention to the consumption of edible plants containing sufficient magnesium as part of the diet to prevent severe COVID-19. In this study, we have described the beneficial effects of sufficient magnesium levels to control COVID-19 and the importance of plant-based magnesium-rich diets. Additionally, we have listed some edible magnesium-rich plants.

The Possible Role of Glucose-6-Phosphate Dehydrogenase in the SARS-CoV-2 Infection

Glucose-6-phosphate dehydrogenase (G6PD) is the second rate-limiting enzyme of the pentose phosphate pathway. This enzyme is present in the cytoplasm of all mammalian cells, and its activity is essential for an adequate functioning of the antioxidant system and for the response of innate immunity. It is responsible for the production of nicotinamide adenine dinucleotide phosphate (NADPH), the first redox equivalent, in the pentose phosphate pathway. Viral infections such as SARS-CoV-2 may induce the Warburg effect with an increase in anaerobic glycolysis and production of lactate. This condition ensures the success of viral replication and production of the virion. Therefore, the activity of G6PD may be increased in COVID-19 patients raising the level of the NADPH, which is needed for the enzymatic and non-enzymatic antioxidant systems that counteract the oxidative stress caused by the cytokine storm. G6PD deficiency affects approximately 350–400 million people worldwide; therefore, it is one of the most prevalent diseases related to enzymatic deficiency worldwide. In G6PD-deficient patients exposed to SARS-CoV-2, the amount of NADPH is reduced, increasing the susceptibility for viral infection. There is loss of the redox homeostasis in them, resulting in severe pneumonia and fatal outcomes.

Glucosinolates and their hydrolysis products as potential nutraceuticals to combat cytokine storm in SARS-COV-2

INTRODUCTION

The high mortality rate in severe cases of COVID-19 is mainly due to the strong upregulation of cytokines, called a cytokine storm. Hyperinflammation and multiple organ failure comprise the main clinical features of a cytokine storm. Nrf2 is a transcription factor which regulates the expression of genes involved in immune and inflammatory processes. Furthermore, Nrf2, as a master regulator, controls the activity of NF-κB which binds to the promoter of many pro-inflammatory genes inducible of various inflammatory factors. Inhibition of Nrf2 response was recently demonstrated in biopsies from patients with COVID-19, and Nrf2 agonists inhibited SARS-CoV-2 replication across cell lines in vitro. Glucosinolates and their hydrolysis products have excellent anti-inflammatory and antioxidant effects via the Nrf2 activation pathway, reduction in the NF-κB activation, and subsequent reduced cytokines levels.

CONCLUSION

Accordingly, these compounds can be helpful in combating the cytokine storm associated with COVID-19.

Red Wine and Health: Approaches to Improve the Phenolic Content During Winemaking

There is ample evidence regarding the health benefits of red wine consumption due to its content of phenolic compounds, as an alternative to improve the state of health and prevent various diseases, being the implementation of procedures that allow a greater extraction and stability of phenolic compounds during the elaboration a key aspect. The first part of this review summarizes some studies, mostly at the preclinical level, on the mechanisms by which phenolic compounds act in the human organism, taking advantage of their antioxidant, anti-inflammatory, antitumor, antithrombotic, antiatherogenic, antimicrobial, antiviral, and other activities. Although the migration of grape components into the must/wine occurs during the winemaking process, the application of new technologies may contribute to increasing the content of phenolic compounds in the finished wine. Some of these technologies have been evaluated on an industrial scale, and in some cases, they have been included in the International Code of Oenological Practice by the International Organization of Vine and Wine (OIV). In this sense, the second part of this review deals with the use of these novel technologies that can increase, or at least maintain, the polyphenol content. For example, in the pre-fermentative stage, phenolic extraction can be increased by treating the berries or must with high pressures, pulsed electric fields (PEF), ultrasound (US), e-beam radiation or ozone. At fermentative level, yeasts with high production of pyranoanthocyanins and/or their precursor molecules, low polyphenol absorption, and low anthocyanin-β-glucosidase activity can be used. Whereas, at the post-fermentative level, aging-on-lees (AOL) can contribute to maintaining polyphenol levels, and therefore transmitting health benefits to the consumer.

Combined Network Pharmacology, Molecular Docking, and Experimental Verification Approach to Investigate the Potential Mechanisms of Polydatin Against COVID-19

Background: Coronavirus disease 2019 (COVID-19) has posed a serious threat to human health and there is an urgent need for drug development. In this study, we explored the potential mechanisms underlying the efficacy of polydatin against COVID-19. Methods: A combined approach of network pharmacology, molecular docking, and experimental verification were employed in this study. Potential targets of polydatin for treating COVID-19 were obtained from multiple drug and disease databases. Protein–protein interaction and enrichment analyses were performed to predict the potential mechanism of action of polydatin against COVID-19. The binding potential of polydatin and key targets was evaluated through molecular docking. Furthermore, experimental methods including flow cytometry and luciferase assay were used to validate the results of computational analyses. Results: The main diseases identified as polydatin targets included metabolic diseases, lung diseases, inflammation, infectious diseases, and tumors. Polydatin may be used to treat COVID-19 through interventions that alter the immune and inflammatory responses, including IL-17 signaling pathway, T-cell activation, cytokines and inflammatory response, lipopolysaccharide-mediated signaling pathway, as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) innate immunity evasion and cell-specific immune response. Polydatin can potentially bind to the target proteins related to COVID-19, such as SARS-CoV-2 Mpro, RdRp, and human angiotensin-converting enzyme 2 (ACE2), while directly exerting its regulatory or therapeutic functions. The experimental results showed that polydatin decreased the infectivity of the SARS-CoV-2 spike pseudovirus in HEK293T-ACE2 cells. Accordingly, polydatin may retard the entry of SARS-CoV-2 into cells by competitively binding to human ACE2. Conclusion: The potential targets and signaling pathways of polydatin against COVID-19 were preliminarily identified. The findings may benefit the development and application of polydatin as a treatment for COVID-19.

Polydatin Improves Sepsis-Associated Encephalopathy by Activating Sirt1 and Reducing p38 Phosphorylation

INTRODUCTION

Our previous study confirmed that polydatin (PD) can alleviate sepsis-induced multiorgan dysfunction (in the vascular endothelium, kidney, and small intestine) by activating Sirt1 and that PD protects against traumatic brain injury in rats via increased Sirt1 and inhibition of the p38-mediated mitogen-activated protein kinase (MAPK) pathway. We aim to investigate whether PD may also attenuate sepsis-associated encephalopathy (SAE).

METHODS

In this study, we constructed an SAE mouse model by cecal ligation and puncture (CLP) and measured Sirt1 protein activity, p38 phosphorylation, brain tissue pathological damage, pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), mitochondrial function (mitochondrial membrane potential, ATP content, and reactive oxygen species), neurological function, and animal survival time. Sirt1 selective inhibitor Ex527 and p38 inhibitor SB203580 were used to explore the possible mechanism of PD in SAE.

RESULTS

We confirmed that PD inhibits neuroinflammation evidenced by reduced proinflammatory cytokines. In addition, PD protects mitochondria as demonstrated by restored mitochondrial membrane potential and adenosine triphosphate (ATP) content, and decreased reactive oxygen species (ROS) level. As we expected, p38 inhibition reduces neuroinflammation and mitochondrial damage. In contrast, Sirt1 inhibition aggravates cerebral cortex mitochondrial damage and neuroinflammation and promotes phosphorylation of p38. Mechanistically, PD treatment suppressed p38 phosphorylation and consequently reduced the neuroinflammatory response, and these effects were blocked by the Sirt selective inhibitor Ex527.

CONCLUSIONS

This study, to the best of our knowledge, is the first to demonstrate that PD alleviates SAE, at least partially, by upregulating Sir1-mediated neuroinflammation inhibition and mitochondrial function protection.

Protective Role of Combined Polyphenols and Micronutrients against Influenza A Virus and SARS-CoV-2 Infection In Vitro

Polyphenols have been widely studied for their antiviral effect against respiratory virus infections. Among these, resveratrol (RV) has been demonstrated to inhibit influenza virus replication and more recently, it has been tested together with pterostilbene against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In the present work, we evaluated the antiviral activity of polydatin, an RV precursor, and a mixture of polyphenols and other micronutrients, named A5+, against influenza virus and SARS-CoV-2 infections. To this end, we infected Vero E6 cells and analyzed the replication of both respiratory viruses in terms of viral proteins synthesis and viral titration. We demonstrated that A5+ showed a higher efficacy in inhibiting both influenza virus and SARS-CoV-2 infections compared to polydatin treatment alone. Indeed, post infection treatment significantly decreased viral proteins expression and viral release, probably by interfering with any step of virus replicative cycle. Intriguingly, A5+ treatment strongly reduced IL-6 cytokine production in influenza virus-infected cells, suggesting its potential anti-inflammatory properties during the infection. Overall, these results demonstrate the synergic and innovative antiviral efficacy of A5+ mixture, although further studies are needed to clarify the mechanisms underlying its inhibitory effect.