Assessment of the therapeutic potential of salubrinal for ME/CFS and long-COVID

Highlights:

  • Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are enigmatic diseases sharing many characteristics.
  • The most debilitating aspects of these diseases are cognitive dysfunction, ‘brain fog’, and exercise intolerance, ‘post-exertional malaise’.
  • There is no cure for these diseases; treatment is palliative only.
  • Mitochondrial dysfunction with endoplasmic reticulum (ER) stress occurs in both diseases.
  • Salubrinal inhibits the phosphatase that dephosphorylates phospho-eukaryotic initiation factor-2α (peIF2α), a protective protein for cells undergoing ER stress when phosphorylated.
  • Salubrinal reduces the formation of Wiskott–Aldrich syndrome protein family member 3 (WASF3), a protein that causes mitochondrial dysfunction that is overexpressed in a cohort of ME/CFS patients.
  • Salubrinal reduces WASF3 expression, restoring mitochondrial function in fibroblasts of a patient with ME/CFS.

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic debilitating condition with no cure that shares commonality with long-COVID.

This review examines current understanding of long-COVID symptoms, characteristics of the affected population, the connection with ME/CFS, and the potential for salubrinal, an agent known for its influence on cellular stress pathways, to mitigate these disorders.

It also describes the historical development and mechanism of action of salubrinal, to mitigate endoplasmic reticulum (ER)/cellular stress responses, that could potentially contribute to symptom improvement in both ME/CFS and long-COVID patients.

Further research and clinical trials are warranted to advance our understanding of the potential role of salubrinal in improving the quality of life for individuals with long-COVID-related ME/CFS symptoms as well as ME/CFS patients.

Source: Aseel Warrayat, Ayah Ali, Joulin Waked, Darcy Tocci, Robert C. Speth. Assessment of the therapeutic potential of salubrinal for ME/CFS and long-COVID. Trends in Molecular Medicine, 2024. ISSN 1471-4914, https://doi.org/10.1016/j.molmed.2024.10.001. https://www.sciencedirect.com/science/article/abs/pii/S1471491424002685

Six-Week Supplementation with Creatine in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Magnetic Resonance Spectroscopy Feasibility Study at 3 Tesla

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic medical condition with no specific pharmacological treatment. Creatine, a nutrient essential for maintaining energy homeostasis in the cells, is a candidate for interventions in ME/CFS.

Methods: Fourteen participants with ME/CFS received supplementation with 16 g creatine monohydrate for 6 weeks. Before starting creatine and on the last day of treatment, participants underwent brain magnetic resonance spectroscopy (MRS) scanning of the pregenual anterior cingulate cortex (pgACC) and dorsolateral prefrontal cortex (DLPFC), followed by symptom, cognition, and hand-grip strength assessments.

Results: Eleven participants completed the study. Creatine treatment increased creatine concentration in both the pgACC and DLPFC (p = 0.004 and 0.012, respectively), decreased fatigue and reaction time (RT) on congruent and incongruent trials of the Stroop test (p = 0.036 and 0.014, respectively), and increased hand-grip strength (p = 0.0004). There was a positive correlation between increases in pgACC creatine and changes in RT on Stroop congruent and incongruent trials (p = 0.048 and p = 0.022, respectively). Creatine was well tolerated, and none of the participants stopped treatment.

Conclusion: Creatine supplementation over six weeks in ME/CFS patients increased brain creatine and improved fatigue and some aspects of cognition. Despite its methodological limitations, this study encourages placebo-controlled investigations of creatine treatment in ME/CFS.

Source: Godlewska BR, Sylvester AL, Emir UE, Sharpley AL, Clarke WT, Martens MAG, Cowen PJ. Six-Week Supplementation with Creatine in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Magnetic Resonance Spectroscopy Feasibility Study at 3 Tesla. Nutrients. 2024 Sep 30;16(19):3308. doi: 10.3390/nu16193308. PMID: 39408275. https://www.mdpi.com/2072-6643/16/19/3308 (Full text)

Inspiratory muscle training improves autonomic function in myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of SARS-CoV-2: a pilot study

Abstract:

Post-acute sequelae of SARS-CoV-2 (PASC), or Long COVID, and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are debilitating post-viral conditions with many symptomatic overlaps, including exercise intolerance and autonomic dysfunction. Both conditions are growing in prevalence, and effective safe treatment strategies must be investigated. We hypothesized that inspiratory muscle training (IMT) could be used in PASC and mild to moderate ME/CFS to mitigate symptoms, improve exercise capacity, and improve autonomic function.

We recruited healthy controls (n=12; 10 women), people with PASC (n=9; 8 women), and people with mild to moderate ME/CFS (n=12; 10 women) to complete 8 weeks of IMT. This project was registered as a clinical trial (NCT05196529) with clinicaltrials.gov.

After completion of IMT, all groups experienced improvements in inspiratory muscle pressure (p<0.001), 6-minute walk distance (p=0.002), resting heart rate (p=0.037), heart rate variability (p<0.05), and symptoms related to sleep (p=0.009). In the ME/CFS group only, after completion of IMT, there were additional improvements with regard to vascular function (p=0.001), secretomotor function (p=0.023), the total weighted score (p=0.005) of the COMPASS 31 autonomic questionnaire, and symptoms related to pain (p=0.016).

We found that after 8 weeks of IMT, people with PASC and/or ME/CFS could see some overall improvements in their autonomic function and symptomology.

Source: Edgell H, Pereira TJ, Kerr K, Bray R, Tabassum F, Sergio L, Badhwar S. Inspiratory muscle training improves autonomic function in myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of SARS-CoV-2: a pilot study. Respir Physiol Neurobiol. 2024 Oct 5:104360. doi: 10.1016/j.resp.2024.104360. Epub ahead of print. PMID: 39374820. https://www.sciencedirect.com/science/article/pii/S1569904824001538 (Full text)

A multimodal approach for treating post-acute infectious syndrome

Abstract:

Long-term complications, such as extensive fatigue and cognitive issues, are known from various infections, including SARS-CoV-2, influenza
virus, or Borrelia burgdorferi. The pathology is mostly unknown and differs between patients. Unfortunately, there is currently no common and
effective treatment. In this perspective, we imply that post-acute infectious syndromes are due to a variety of factors, including among others
diminished tissue perfusion, tissue infiltration by viruses, inflammation, and oxidative stress, and that not one specific biomarker can be used
to measure these syndromes. Thus, we suggest that a score based on a number of criteria/factors should be used to assess post-acute infectious
syndromes.

Consequently, probably not one single treatment can be used to treat this group of patients, and we suggest a multimodal
treatment regimen comprising a combination of pharmacotherapy, such as metformin and naltrexone with anti-inflammatory effects,
alongside physical therapies such as extracorporeal apheresis and transcutaneous neurotherapy. This combined approach aims to reduce
biomarker levels and enhance cognitive functions. This implies that a reset of the systems can be achieved by a multimodal approach based on a
score for post-acute infectious syndromes.

Source:  Charlotte Steenblock, Nicole Toepfner, Yannick P. Kok, Philip Mavberg, Horst Bruckmoser, Alfons Breu, Johannes Korth, Harald Heidecke, Milo A. Puhan, and Stefan R. Bornstein. A multimodal approach for treating post-acute infectious syndrome. Brain Medicine (2024) 1, 1–7; doi: https://doi.org/10.61373/bm024p.0064; Published online: 30 August 2024. https://bm.genomicpress.com/wp-content/uploads/2024/08/BM0064-Steenblock-2024.pdf (Full text)

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment

Abstract:

Objective: To report the prevalence and severity of nonpelvic symptoms for patients with venous-origin chronic pelvic pain (VO-CPP) and to describe outcomes after pelvic vein stenting and embolization.

Methods: We retrospectively reviewed outcomes of 45 women with VO-CPP who underwent treatment with iliac vein stenting and/or embolization. Patients completed symptom-severity questionnaires before and after treatment that assessed for pelvic pain, and multiple other symptoms, including brain fog, anxiety, depression, musculoskeletal pain, fatigue, migraines and more.

Results: Patient age ranged from 18 to 65 years. The prevalence of common symptoms was as follows: migraines, 69%; brain fog, 76%; anxiety attacks, 58%; excess sweating, 64%; hip pain, 73%; diarrhea, 62%; constipation, 76%; and abdominal bloating, 82%. After treatment, most symptom scores improved by more than 50%; exceptions were excessive sweating (41% improvement) and bloating (47% improvement). Prevalence of individual symptoms that bundle into POTS ranged from 29% to 76%, where symptom improvement ranged from 23% to 59% after treatment. Overlapping individual symptoms characteristic of fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) were present in 64% to 82% of patients and all improved by 49% to 63% after treatment.

Conclusions: Pelvic venous flow abnormality is linked causally to a spectrum of interrelated symptoms, of which many can be bundled into named syndromes of unknown cause. With catheter- based treatment of pelvic venous pooling, nonpelvic symptom and syndrome scores improved.

Source: Smith SJ, Smith BH, Sichlau MJ, Chen B, Knight D, Rowe PC. Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment. Phlebology. 2024 Aug 10:2683555241273109. doi: 10.1177/02683555241273109. Epub ahead of print. PMID: 39126670.  https://pubmed.ncbi.nlm.nih.gov/39126670/

Six-year follow-up of participants in two clinical trials of rituximab or cyclophosphamide in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Objectives: In this six-year follow-up study, we used patient-reported outcome measures (PROMs) to compare values at baseline, at 18 months, and at six-year follow up from the CycloME and the RituxME trials.

Methods: Based on the hypothesis that ME/CFS in a subgroup of patients is a variant of an autoimmune disease, we performed two clinical trials between 2014 and 2017. The RituxME trial was a randomized, double-blind and placebo-controlled phase III trial of 151 patients, assessing the B-cell depleting antibody rituximab. The CycloME trial was an open-label phase II trial of 40 patients using intravenous cyclophosphamide. Here we report six-year follow-up from both trials, using the Short Form 36 Physical Function (SF-36 PF) and DePaul short form (DSQ-SF) questionnaires.

Result: Of the patients available after six years, 75.7% of RituxME and 94.4% of CycloME patients participated. In the RituxME rituximab group, the mean SF-36 PF scores were 32.9 at baseline, 42.4 at 18 months and 45.5 at six years. In the placebo group, the mean SF-36 PF scores were 32.3 at baseline, 45.5 at 18 months and 43.1 at six years. In the CycloME trial, mean SF-36 PF increased from 35.4 at baseline to 54.4 at 18 months, and 56.7 at six years. At six-year follow-up, 44.1% of cyclophosphamide-, 27.6% of rituximab- and 20.4% of placebo-treated patients had an SF-36 PF ≥ 70, and further, 17.6%, 8.6% and 7.4% of the corresponding patient groups had an SF-36 PF ≥ 90, which is within normal range. In terms of worsening at six years, 5.9% of cyclophosphamide-treated, 10.3% of rituximab-, and 14.8% of placebo-treated patients had a drop in SF-36 PF of 20 points or more from baseline. There were no serious unexpected adverse reactions.

Conclusions: After six years, 44.1% of the cyclophosphamide group scored an SF-36 PF of at least 70, and 17.6% of at least 90, suggesting that cyclophosphamide in a subgroup may modulate the disease course in a beneficial way. However, cyclophosphamide carries toxicity concerns and should not be used for ME/CFS patients outside clinical trials. Rather, these data should encourage efforts to better understand the disease mechanisms and to search for targeted and less toxic immune modulatory treatment for this patient group.

Source: Rekeland IG, Sørland K, Neteland LL, Fosså A, Alme K, Risa K, Dahl O, Tronstad KJ, Mella O, Fluge Ø. Six-year follow-up of participants in two clinical trials of rituximab or cyclophosphamide in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. PLoS One. 2024 Jul 23;19(7):e0307484. doi: 10.1371/journal.pone.0307484. PMID: 39042627; PMCID: PMC11265720. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11265720/ (Full text)

Potential pathophysiological role of the ion channel TRPM3 in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and the therapeutic effect of low-dose naltrexone

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating disease with a broad overlap of symptomatology with Post-COVID Syndrome (PCS). Despite the severity of symptoms and various neurological, cardiovascular, microvascular, and skeletal muscular findings, no biomarkers have been identified.

The Transient receptor potential melastatin 3 (TRPM3) channel, involved in pain transduction, thermosensation, transmitter and neuropeptide release, mechanoregulation, vasorelaxation, and immune defense, shows altered function in ME/CFS. Dysfunction of TRPM3 in natural killer (NK) cells, characterized by reduced calcium flux, has been observed in ME/CFS and PCS patients, suggesting a role in ineffective pathogen clearance and potential virus persistence and autoimmunity development.

TRPM3 dysfunction in NK cells can be improved by naltrexone in vitro and ex vivo, which may explain the moderate clinical efficacy of low-dose naltrexone (LDN) treatment. We propose that TRPM3 dysfunction may have a broader involvement in ME/CFS pathophysiology, affecting other organs. This paper discusses TRPM3’s expression in various organs and its potential impact on ME/CFS symptoms, with a focus on small nerve fibers and the brain, where TRPM3 is involved in presynaptic GABA release.

Source: Löhn M, Wirth KJ. Potential pathophysiological role of the ion channel TRPM3 in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and the therapeutic effect of low-dose naltrexone. J Transl Med. 2024 Jul 5;22(1):630. doi: 10.1186/s12967-024-05412-3. PMID: 38970055; PMCID: PMC11227206. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11227206/ (Full Text)

Cardiopulmonary and metabolic responses during a 2-day CPET in myalgic encephalomyelitis/chronic fatigue syndrome: translating reduced oxygen consumption to impairment status to treatment considerations

Abstract:

Background: Post-exertional malaise (PEM), the hallmark symptom of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), represents a constellation of abnormal responses to physical, cognitive, and/or emotional exertion including profound fatigue, cognitive dysfunction, and exertion intolerance, among numerous other maladies. Two sequential cardiopulmonary exercise tests (2-d CPET) provide objective evidence of abnormal responses to exertion in ME/CFS but validated only in studies with small sample sizes. Further, translation of results to impairment status and approaches to symptom reduction are lacking.

Methods: Participants with ME/CFS (Canadian Criteria; n = 84) and sedentary controls (CTL; n = 71) completed two CPETs on a cycle ergometer separated by 24 h. Two-way repeated measures ANOVA compared CPET measures at rest, ventilatory/anaerobic threshold (VAT), and peak effort between phenotypes and CPETs. Intraclass correlations described stability of CPET measures across tests, and relevant objective CPET data indicated impairment status. A subset of case–control pairs (n = 55) matched for aerobic capacity, age, and sex, were also analyzed.

Results: Unlike CTL, ME/CFS failed to reproduce CPET-1 measures during CPET-2 with significant declines at peak exertion in work, exercise time, e, O2CO2 T, HR, O2pulse, DBP, and RPP. Likewise, CPET-2 declines were observed at VAT for e/CO2, PetCO2, O2pulse, work, O2 and SBP. Perception of effort (RPE) exceeded maximum effort criteria for ME/CFS and CTL on both CPETs. Results were similar in matched pairs. Intraclass correlations revealed greater stability in CPET variables across test days in CTL compared to ME/CFS owing to CPET-2 declines in ME/CFS. Lastly, CPET-2 data signaled more severe impairment status for ME/CFS compared to CPET-1.

Conclusions: Presently, this is the largest 2-d CPET study of ME/CFS to substantiate impaired recovery in ME/CFS following an exertional stressor. Abnormal post-exertional CPET responses persisted compared to CTL matched for aerobic capacity, indicating that fitness level does not predispose to exertion intolerance in ME/CFS. Moreover, contributions to exertion intolerance in ME/CFS by disrupted cardiac, pulmonary, and metabolic factors implicates autonomic nervous system dysregulation of blood flow and oxygen delivery for energy metabolism. The observable declines in post-exertional energy metabolism translate notably to a worsening of impairment status. Treatment considerations to address tangible reductions in physiological function are proffered.

Trial registration number: ClinicalTrials.gov, retrospectively registered, ID# NCT04026425, date of registration: 2019-07-17.

Source: Keller, B., Receno, C.N., Franconi, C.J. et al. Cardiopulmonary and metabolic responses during a 2-day CPET in myalgic encephalomyelitis/chronic fatigue syndrome: translating reduced oxygen consumption to impairment status to treatment considerations. J Transl Med 22, 627 (2024). https://doi.org/10.1186/s12967-024-05410-5 https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-024-05410-5#Abs1 (Full text)

 

Successful Subcutaneous Immunoglobulin Therapy in a Case Series of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Purpose: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remains an enigma with no curable treatment options at hand. Although patients with ME/CFS are a heterogeneous group, a large proportion of patients present with an infection-driven symptomatology, making them potential responders to immunologic treatments, such as immunoglobulin (IG). Previous studies on IG treatment in patients with ME/CFS have not been consistent but have described beneficial effects in subgroups of patients.

Methods: Here we present data on a series of cases (n = 17) with infection-related ME/CFS (as defined by disease history and ongoing recurrent infections) treated with subcutaneous low-dose IG (0.06 g/kg/mo) over 5 weeks with continuous monitoring of symptoms.

Findings: Patients were predominantly female (65%) with mild-to-moderate disease severity (82%) and with poor self-reported quality of life (median, 25 on a 0-100 scale) and working ability (median, 5 on a 0-100 scale) before treatment. After 5 weeks of treatment with low-dose IG, significant improvements in symptoms, quality of life, and working ability were noted (all P < 0.05). Among the 7 patients who reported the highest benefit of the treatment, quality of life increased by 35 units (on a 0-100 scale), with 1 patient reporting complete elimination of ME/CFS symptoms. No serious side effects were detected with the treatment.

Implications: In this limited-sized case series, we found pronounced beneficial effects of low-dose IG in a large proportion of patients with infection-related ME/CFS. Further well-controlled studies are needed to verify the potential benefits of IG treatment in patients with ME/CFS with infection-driven symptomatology.

Source: Sjogren P, Bragée B, Britton S. Successful Subcutaneous Immunoglobulin Therapy in a Case Series of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Clin Ther. 2024 Jun 22:S0149-2918(24)00131-0. doi: 10.1016/j.clinthera.2024.05.010. Epub ahead of print. PMID: 38910072.

Interdisciplinary, collaborative D-A-CH (Germany, Austria and Switzerland) consensus statement concerning the diagnostic and treatment of myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe, chronic multisystemic disease which, depending on its severity, can lead to considerable physical and cognitive impairment, loss of ability to work and the need for nursing care including artificial nutrition and, in very severe cases, even death.

The aim of this D-A-CH (Germany, Austria, Switzerland) consensus statement is 1) to summarize the current state of knowledge on ME/CFS, 2) to highlight the Canadian Consensus Criteria (CCC) as clinical criteria for diagnostics with a focus on the leading symptom post-exertional malaise (PEM) and 3) to provide an overview of current options and possible future developments, particularly with regard to diagnostics and therapy. The D-A-CH consensus statement is intended to support physicians, therapists and valuer in diagnosing patients with suspected ME/CFS by means of adequate anamnesis and clinical-physical examinations as well as the recommended clinical CCC, using the questionnaires and other examination methods presented.

The overview of the two pillars of therapy for ME/CFS, pacing and symptom-relieving therapy options, is intended not only to provide orientation for physicians and therapists, but also to support decision-makers from healthcare policy and insurance companies in determining which therapy options should already be reimbursable by them at this point in time for the indication ME/CFS.

Source: Hoffmann K, Hainzl A, Stingl M, Kurz K, Biesenbach B, Bammer C, Behrends U, Broxtermann W, Buchmayer F, Cavini AM, Fretz GS, Gole M, Grande B, Grande T, Habermann-Horstmeier L, Hackl V, Hamacher J, Hermisson J, King M, Kohl S, Leiss S, Litzlbauer D, Renz-Polster H, Ries W, Sagelsdorff J, Scheibenbogen C, Schieffer B, Schön L, Schreiner C, Thonhofer K, Strasser M, Weber T, Untersmayr E. Interdisziplinäres, kollaboratives D-A-CH Konsensus-Statement zur Diagnostik und Behandlung von Myalgischer Enzephalomyelitis/Chronischem Fatigue-Syndrom [Interdisciplinary, collaborative D-A-CH (Germany, Austria and Switzerland) consensus statement concerning the diagnostic and treatment of myalgic encephalomyelitis/chronic fatigue syndrome]. Wien Klin Wochenschr. 2024 Aug;136(Suppl 5):103-123. German. doi: 10.1007/s00508-024-02372-y. Epub 2024 May 14. PMID: 38743348. https://pubmed.ncbi.nlm.nih.gov/38743348/