Oxidative Stress is a shared characteristic of ME/CFS and Long COVID

Abstract:

More than 65 million individuals worldwide are estimated to have Long COVID (LC), a complex multisystemic condition, wherein patients of all ages report fatigue, post-exertional malaise, and other symptoms resembling myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). With no current treatments or reliable diagnostic markers, there is an urgent need to define the molecular underpinnings of these conditions.

By studying bioenergetic characteristics of peripheral blood lymphocytes in over 16 healthy controls, 15 ME/CFS, and 15 LC, we find both ME/CFS and LC donors exhibit signs of elevated oxidative stress, relative to healthy controls, especially in the memory subset. Using a combination of flow cytometry, bulk RNA-seq analysis, mass spectrometry, and systems chemistry analysis, we also observed aberrations in ROS clearance pathways including elevated glutathione levels, decreases in mitochondrial superoxide dismutase levels, and glutathione peroxidase 4 mediated lipid oxidative damage.

Critically, these changes in redox pathways show striking sex-specific trends. While females diagnosed with ME/CFS exhibit higher total ROS and mitochondrial calcium levels, males with an ME/CFS diagnosis have normal ROS levels, but larger changes in lipid oxidative damage. Further analyses show that higher ROS levels correlates with hyperproliferation of T cells in females, consistent with the known role of elevated ROS levels in the initiation of proliferation. This hyperproliferation of T cells can be attenuated by metformin, suggesting this FDA-approved drug as a possible treatment, as also suggested by a recent clinical study of LC patients.

Thus, we report that both ME/CFS and LC are mechanistically related and could be diagnosed with quantitative blood cell measurements. We also suggest that effective, patient tailored drugs might be discovered using standard lymphocyte stimulation assays.

Source: Vishnu Shankar, Julie Wilhelmy, Basil Michael, Layla Cervantes, Vamsee Mallajosyula, Ronald Davis, Michael Snyder, Shady Younis,
William H Robinson, Sadasivan Shankar, Paul Mischel, Hector Bonilla, Mark Davis. Oxidative Stress is a shared characteristic of ME/CFS and Long COVID. bioRxiv 2024.05.04.592477; doi: https://doi.org/10.1101/2024.05.04.592477  https://www.biorxiv.org/content/10.1101/2024.05.04.592477v1https://www.biorxiv.org/content/10.1101/2024.05.04.592477v1 (Full text available as PDF file)

Pharmacological evaluation of vitamin D in COVID-19 and long COVID-19: recent studies confirm clinical validation and highlight metformin to improve VDR sensitivity and efficacy

Abstract:

Nearly four years after its first appearance, and having gone from pandemic to endemic, the SARS-CoV-2 remains out of control globally. The purpose of this study was to evaluate the clinical efficacy of vitamin D (VD) in COVID-19 and long COVID-19, explain the discrepancy in clinical outcomes and highlight the potential impact of metformin on VD efficacy in recent articles.

Articles from January 2022 to August 2023 were selected for this review. The objective of this study was achieved by reviewing, analyzing, and discussing articles demonstrating (1) the mechanism of action of VD (2) observational or randomized clinical trials (RCTs) that support or not the beneficial clinical effects of VD in COVID-19 or long COVID. (3) genetic and non-genetic reasons for the variation in the effects of VD.

Articles were collected from electronic databases such as PubMed, Scopus, MEDLINE, Google Scholar, Egyptian Knowledge Bank, Science Direct, and Cochrane Database of Systematic Reviews. Twenty three studies conducted in vitro or in animal models indicated that VD may act in COVID-19 through protecting the respiratory system by antimicrobial peptide cathelicidins, reducing lung inflammation, regulating innate and adaptive immune functions and up regulation of autophagy gene activity. Our review identified 58 clinical studies that met the criteria. The number of publications supporting a beneficial clinical activity of VD in treating COVID-19 was 49 (86%), including 12 meta-analyses. Although the total patients included in all articles was 14,071,273, patients included in publications supporting a beneficial role of VD in COVID-19 were 14,029,411 (99.7%).

Collectively, extensive observational studies indicated a decisive relationship between low VD levels and the severity of COVID-19 and mortality outcomes. Importantly, evidence from intervention studies has demonstrated the effectiveness of VD supplements in treating COVID-19. Furthermore, the results of 4 observational studies supported the beneficial role of VD in alleviating symptoms of long COVID-19 disease. However, eight RCTs and one meta-analysis of RCTs may contain low-grade evidence against a beneficial role of VD in COVID-19. Twenty-five articles have addressed the association between VDR and DBP genetic polymorphisms and treatment failure of VD in COVID-19.

Impaired VDR signaling may underlie the variability of VD effects as non-genetic mechanisms. Interestingly, in recent studies, metformin has a beneficial therapeutic role in COVID-19 and long COVID-19, possibly by improving AMPK signaling of the VDR and enhancing the efficacy of the VD. In conclusion, evidence has been significantly strengthened over the past 18 months, with several meta-analyses and RCTs reporting conclusive beneficial effects of VD supplementation against COVID-19 and highlighting metformin to improve VDR sensitivity and efficacy in treating COVID-19 and long COVID-19.

Source: Gomaa, A.A., Abdel-Wadood, Y.A., Thabet, R.H. et al. Pharmacological evaluation of vitamin D in COVID-19 and long COVID-19: recent studies confirm clinical validation and highlight metformin to improve VDR sensitivity and efficacy. Inflammopharmacol (2023). https://doi.org/10.1007/s10787-023-01383-x https://link.springer.com/article/10.1007/s10787-023-01383-x (Full text)

Long and Short-term Metformin Consumption as a Potential Therapy to Prevent Complications of COVID-19

Abstract:

Purpose: The aim of the study is to evaluate the effect of metformin in complication improvement of hospitalized patients with COVID-19.

Methods: This was a randomized clinical trial that involved 189 patients with confirmed COVID-19 infection. Patients in the intervention group received metformin-500 mg twice daily. Patients who received metformin before admission were excluded from the control group. Patients who were discharged before taking at least 2000 mg of metformin were excluded from the study. Primary outcomes were vital signs, need for ICU admission, need for intubation, and mortality.

Results: Data showed that patients with diabetes with previous metformin in their regimen had lower percentages of ICU admission and death in comparison with patients without diabetes (11.3% vs. 26.1% (P=0.014) and 4.9% vs. 23.9% (P≤0.001), respectively). Admission time characteristics were the same for both groups except for diabetes and hyperlipidemia, which were significantly different between the two groups. Observations of naproxen consumption on endpoints, duration of hospitalization, and the levels of spO2 did not show any significant differences between the intervention and the control group. The adjusted OR for intubation in the intervention group versus the control group was 0.21 [95% CI, 0.04-0.99 (P=0.047)].

Conclusion: In this trial, metformin consumption had no effect on mortality and ICU admission rates in non-diabetic patients. However, metformin improved COVID-19 complications in diabetic patients who had been receiving metformin prior to COVID-19 infection, and it significantly lowered the intubation rates.

Source: Shaseb E, Ghaffary S, Garjani A, Zoghi E, Maleki Dizaji N, Soltani S, Sarbakhsh P, Somi MH, Valizadeh P, Taghizadieh A, Faghihdinevari M, Varshochi M, Naghily B, Bayatmakoo Z, Saleh P, Taghizadeh S, Haghdoost M, Owaysi H, Ravanbakhsh Ghavghani F, Tarzamni MK, Moradi R, Javan Ali Azar F, Shabestari Khiabani S, Ghazanchaei A, Hamedani S, Hatefi S. Long and Short-term Metformin Consumption as a Potential Therapy to Prevent Complications of COVID-19. Adv Pharm Bull. 2023 Jul;13(3):621-626. doi: 10.34172/apb.2023.066. Epub 2022 Jul 2. PMID: 37646067; PMCID: PMC10460805. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10460805/ (Full text)

Experimental drugs in randomized controlled trials for long-COVID: what’s in the pipeline? A systematic and critical review

Article highlights:

  • Presently, no standard treatment exists for long-COVID, a post-coronavirus disease 2019 (COVID-19) syndrome, characterized by symptoms such as fatigue and brain fog lasting for 3 months or more after acute COVID-19.
  • Owing to increased funding, increasing numbers of randomized controlled trials (RCTs) on drug treatments for long-COVID are being conducted. We systematically and critically reviewed these RCTs to pinpoint drugs with high potential for treating long-COVID.
  • Of the four completed RCTs identified, three examined long-COVID prevention, of which only metformin was deemed to exhibit high potential in preventing long-COVID when administered during acute COVID-19. Only one RCT investigated the potential efficacy of a drug (Treamid) in treating ongoing long-COVID, showing low to modest potential due to its inefficacy in improving the more meaningful outcomes of long-COVID.
  • Of the 22 ongoing RCTs identified, only rintatolimod and LYT-100 (deupirfenidone) were judged as possessing modest to high potential for treating long-COVID.
  • The fact that nearly all of the drug candidates did not seem to exhibit high potential in treating long-COVID is a testament to the ordeal of treating long-COVID.
  • Given that long-COVID is a multifaceted condition with multiple proposed subtypes, its treatment may need to be tailored to specific subtypes.

Abstract:

Introduction: Over three years have passed since the emergence of coronavirus disease 2019 (COVID-19), and yet the treatment for long-COVID, a post-COVID-19 syndrome, remains long overdue. Currently, there is no standardized treatment available for long-COVID, primarily due to the lack of funding for post-acute infection syndromes (PAIS). Nevertheless, the past few years have seen a renewed interest in long-COVID research, with billions of dollars allocated for this purpose. As a result, multiple randomized controlled trials (RCTs) have been funded in the quest to find an effective treatment for long-COVID.

Areas covered: This systematic review identified and evaluated the potential of current drug treatments for long-COVID, examining both completed and ongoing RCTs.

Expert opinion: We identified four completed and 22 ongoing RCTs, investigating 22 unique drugs. However, most drugs were deemed to not have high potential for treating long-COVID, according to three pre-specified domains, a testament to the ordeal of treating long-COVID. Given that long-COVID is highly multifaceted with several proposed subtypes, treatments likely need to be tailored accordingly. Currently, rintatolimod appears to have modest to high potential for treating the myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) subtype, LTY-100 and Treamid for pulmonary fibrosis subtype, and metformin for general long-COVID prevention.

Source: Yong SJ, Halim A, Halim M, Ming LC, Goh KW, Alfaresi M, AlShehail BM, Al Fares MA, Alissa M, Sulaiman T, Alsalem Z, Alwashmi ASS, Khamis F, Al Kaabi NA, Albayat H, Alsheheri A, Garout M, Alsalman J, Alfaraj AH, Alhajri M, Dhama K, Alburaiky LM, Alsanad AH, AlShurbaji AT, Rabaan AA. Experimental drugs in randomized controlled trials for long-COVID: what’s in the pipeline? A systematic and critical review. Expert Opin Investig Drugs. 2023 Aug 4:1-13. doi: 10.1080/13543784.2023.2242773. Epub ahead of print. PMID: 37534972. https://pubmed.ncbi.nlm.nih.gov/37534972/

Outpatient Treatment of COVID-19 and the Development of Long COVID Over 10 Months: A Multi-Center, Quadruple-Blind, Parallel Group Randomized Phase 3 Trial

Abstract:

Background: Post-acute sequelae of COVID, termed “Long COVID”, is an emerging chronic illness potentially affecting ~10% of those with COVID-19. We sought to determine if outpatient treatment with metformin, ivermectin, or fluvoxamine could prevent Long COVID.

Methods: COVID-OUT (NCT04510194) was a decentralized, multi-site trial in the United States testing three medications (metformin, ivermectin, fluvoxamine) using a 2×3 parallel treatment factorial randomized assignment to efficiently share placebo controls. Participants, investigators, care providers, and outcomes assessors were masked to randomized treatment assignment. Inclusion criteria included: age 30 to 85 years with overweight or obesity, symptoms <7 days, enrolled within <=3 days of documented SARS-CoV-2 infection. Long COVID diagnosis from a medical provider was a pre-specified secondary outcome assessed by monthly surveys through 300 days after randomization and confirmed in medical records.

Findings: Of 1323 randomized trial participants, 1125 consented for long-term follow up, and 95.1% completed >9 months of follow up. The median age was 45 years (IQR, 37 to 54), and 56% were female (7% pregnant). The median BMI was 30 kg/m2 (IQR, 27 to 34). Overall, 8.4% reported a medical provider diagnosed them with Long COVID; cumulative incidence: 6.3% with metformin and 10.6% with matched placebo. The hazard ratio (HR) for metformin preventing Long COVID was 0.58 (95%CI, 0.38 to 0.88; P=0·009) versus placebo. The metformin effect was consistent across subgroups, including viral variants. When metformin was started within <4 days of symptom onset, the HR for Long COVID was 0.37 (95%CI, 0.15 to 0.95).  No statistical difference in Long COVID occurred in those randomized to either ivermectin (HR=0.99; 95%CI, 0.59 to 1.64) or fluvoxamine (HR=1.36; 95%CI, 0.78 to 2.34).

Interpretations: A 42% relative decrease and 4.3% absolute decrease in the Long COVID incidence occurred in participants who received early outpatient COVID-19 treatment with metformin compared to exact-matching placebo.

Source: Bramante, Carolyn and Buse, John B. and Liebovitz, David and Nicklas, Jacinda and Puskarich, Michael and Cohen, Kenneth R. and Belani, Hrishikesh and Anderson, Blake and Huling, Jared D. and Thompson, Jennifer and Pullen, Matthew and Wirtz, Esteban Lemus and Siegel, Lianne and Proper, Jennifer and Odde, David J. and Klatt, Nichole and Sherwood, Nancy E. and Lindberg, Sarah and Karger, Amy B. and Beckman, Kenneth B. and Erickson, Spencer and Fenno, Sarah and Hartman, Katrina and Rose, Michael and Mehta, Tanvi and Patel, Barkha and Griffiths, Gwendolyn and Bhat, Neeta and Murray, Thomas A. and Boulware, David R., Outpatient Treatment of COVID-19 and the Development of Long COVID Over 10 Months: A Multi-Center, Quadruple-Blind, Parallel Group Randomized Phase 3 Trial. Available at SSRN: https://ssrn.com/abstract=4375620 or http://dx.doi.org/10.2139/ssrn.4375620

News and views in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): The role of co-morbidity and novel treatments

Abstract:

Though affecting many thousands of patients, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) should be considered an orphan disease, since the cause remains elusive and no treatment is available that can provide complete cure. There is reasonable insight into the pathogenesis of signs and symptoms, and treatments specifically directed to immunological, inflammatory and metabolic processes offer relief to an increasing number of patients. Particular attention is given to the importance of co-morbidity requiring appropriate therapy.

Promising results are obtained by treatment with Metformin, or possibly Momordica charantia extract, which will correct insulin resistance, with Meldonium improving the transportation of glucose into the mitochondria, with sodium dichloroacetate activating pyruvate dehydrogenase, and with nutraceutical support reducing oxidative and inflammatory impairment.

Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.

Source: Comhaire F, Deslypere JP. News and views in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): The role of co-morbidity and novel treatments. Med Hypotheses. 2019 Oct 22;134:109444. doi: 10.1016/j.mehy.2019.109444. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31669858

Pharmacological activation of AMPK and glucose uptake in cultured human skeletal muscle cells from patients with ME/CFS

Abstract:

Background: Skeletal muscle fatigue and post-exertional malaise are key symptoms of Myalgic Encephalomyelitis (ME/CFS). We have previously shown that AMPK activation and glucose uptake are impaired in primary human skeletal muscle cell cultures derived from patients with ME/CFS in response to electrical pulse stimulation, a method which induces contraction of muscle cells in vitro. The aim of this study was to assess if AMPK could be activated pharmacologically in ME/CFS.

Methods: Primary skeletal muscle cell cultures from patients with ME/CFS and healthy controls were treated with either metformin or 991. AMPK activation was assessed by Western blot and glucose uptake measured.

Results: Both metformin and 991 treatment significantly increased AMPK activation and glucose uptake in muscle cell cultures from both controls and ME/CFS. Cellular ATP content was unaffected by treatment although ATP content was significantly decreased in ME/CFS compared to controls.

Conclusions: Pharmacological activation of AMPK can improve glucose uptake in muscle cell cultures from patients with ME/CFS. This suggests that the failure of electrical pulse stimulation to activate AMPK in these muscle cultures is due to a defect proximal to AMPK. Further work is required to delineate the defect and determine whether pharmacological activation of AMPK improves muscle function in patients with ME/CFS.

Source: Brown AE, Dibnah B, Fisher E, Newton JL, Walker M. Pharmacological activation of AMPK and glucose uptake in cultured human skeletal muscle cells from patients with ME/CFS. Biosci Rep. 2018 Apr 13. pii: BSR20180242. doi: 10.1042/BSR20180242. [Epub ahead of print]  https://www.ncbi.nlm.nih.gov/pubmed/29654166/