Sleep and circadian rhythm alterations in myalgic encephalomyelitis/chronic fatigue syndrome and post-COVID fatigue syndrome and its association with cardiovascular risk factors: A prospective cohort study

Abstract:

This study aimed to investigate circadian rhythm manifestations in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) patients (including a subpopulation of long-COVID patients) and matched healthy controls while also exploring their association with cardiovascular health variables.

Thirty-one ME/CFS patients (75% females), 23 individuals diagnosed with post-COVID ME/CFS (56% females) and 31 matched healthy controls (68% females) were enrolled in this study. Demographic and clinical characteristics were assessed using validated self-reported outcome measures. Actigraphy data, collected over one week, were used to analyze the 24-h profiles of wrist temperature, motor activity, and sleep circadian variables in the study participants. Associations between lipid profile with endothelial dysfunction biomarkers (such as endothelin-1, ICAM-1 and VCAM-1) and with sleep and circadian variables were also studied.

No differences were found in these variables between the two group of patients. Patients showed lower activity and worse sleep quality than matched healthy controls, together with a worse lipid profile than controls, that was associated with disturbances in the circadian temperature rhythm. ICAM-1 levels were associated with plasma lipids in healthy controls, but not in patients, who showed higher levels of endothelin-1 and VCAM-1.

These findings suggest that lipid profiles in ME/CFS are linked to disrupted circadian rhythms and sleep patterns, likely due to endothelial dysfunction. Furthermore, they highlight the intricate relationship between sleep, circadian rhythms, and cardiovascular health in this condition.

Source: Zerón-Rugerio MF, Zaragozá MC, Domingo JC, Sanmartín-Sentañes R, Alegre-Martin J, Castro-Marrero J, Cambras T. Sleep and circadian rhythm alterations in myalgic encephalomyelitis/chronic fatigue syndrome and post-COVID fatigue syndrome and its association with cardiovascular risk factors: A prospective cohort study. Chronobiol Int. 2024 Jul 22:1-12. doi: 10.1080/07420528.2024.2380020. Epub ahead of print. PMID: 39037125. https://pubmed.ncbi.nlm.nih.gov/39037125/

SARS-CoV-2 infection triggers pro-atherogenic inflammatory responses in human coronary vessels

Abstract:

COVID-19 patients present higher risk for myocardial infarction (MI), acute coronary syndrome, and stroke for up to 1 year after SARS-CoV-2 infection. While the systemic inflammatory response to SARS-CoV-2 infection likely contributes to this increased cardiovascular risk, whether SARS-CoV-2 directly infects the coronary vasculature and attendant atherosclerotic plaques to locally promote inflammation remains unknown. Here, we report that SARS-CoV-2 viral RNA (vRNA) is detectable and replicates in coronary atherosclerotic lesions taken at autopsy from patients with severe COVID-19. SARS-CoV-2 localizes to plaque macrophages and shows a stronger tropism for arterial lesions compared to corresponding perivascular fat, correlating with the degree of macrophage infiltration.

In vitro infection of human primary macrophages highlights that SARS-CoV-2 entry is increased in cholesterol-loaded macrophages (foam cells) and is dependent, in part, on neuropilin-1 (NRP-1). Furthermore, although viral replication is abortive, SARS-CoV-2 induces a robust inflammatory response that includes interleukins IL-6 and IL-1β, key cytokines known to trigger ischemic cardiovascular events. SARS-CoV-2 infection of human atherosclerotic vascular explants recapitulates the immune response seen in cultured macrophages, including pro-atherogenic cytokine secretion.

Collectively, our data establish that SARS-CoV-2 infects macrophages in coronary atherosclerotic lesions, resulting in plaque inflammation that may promote acute CV complications and long-term risk for CV events.

Source: Eberhardt N, Noval MG, Kaur R, Sajja S, Amadori L, Das D, Cilhoroz B, Stewart O, Fernandez DM, Shamailova R, Guillen AV, Jangra S, Schotsaert M, Gildea M, Newman JD, Faries P, Maldonado T, Rockman C, Rapkiewicz A, Stapleford KA, Narula N, Moore KJ, Giannarelli C. SARS-CoV-2 infection triggers pro-atherogenic inflammatory responses in human coronary vessels. bioRxiv [Preprint]. 2023 Aug 15:2023.08.14.553245. doi: 10.1101/2023.08.14.553245. PMID: 37645908; PMCID: PMC10461985. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10461985/ (Full text)

Lipid and protein oxidation in female patients with chronic fatigue syndrome

Abstract:

INTRODUCTION: Chronic fatigue syndrome (CFS) is a widely recognized problem, characterized by prolonged, debilitating fatigue and a characteristic group of accompanying symptoms, that occurs four times more frequently in women than in men. The aim of the study was to determine the existence of oxidative stress and its possible consequences in female patients with CFS.

MATERIAL AND METHODS: Twenty-four women aged 15-45 who fulfilled the diagnostic criteria for CFS with no comorbidities were recruited and were age matched to a control group of 19 healthy women. After conducting the routine laboratory tests, levels of the lipid oxidation product malondialdehyde (MDA) and protein oxidation protein carbonyl (CO) were determined.

RESULTS: The CFS group had higher levels of triglycerides (p = 0.03), MDA (p = 0.03) and CO (p = 0.002) and lower levels of HDL cholesterol (p = 0.001) than the control group. There were no significant differences in the levels of total protein, total cholesterol or LDL cholesterol.

CONCLUSIONS: The CFS group had an unfavorable lipid profile and signs of oxidative stress induced damage to lipids and proteins. These results might be indicative of early proatherogenic processes in this group of patients who are otherwise at low risk for atherosclerosis. Antioxidant treatment and life style changes are indicated for women with CFS, as well as closer observation in order to assess the degree of atherosclerosis.

 

Source: Tomic S, Brkic S, Maric D, Mikic AN. Lipid and protein oxidation in female patients with chronic fatigue syndrome. Arch Med Sci. 2012 Nov 9;8(5):886-91. doi: 10.5114/aoms.2012.31620. Epub 2012 Nov 7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506242/ (Full article)

 

Lipid peroxidation is elevated in female patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Chronic fatigue syndrome is a debilitating disease of unclear cause and pathogenesis. It affects mostly women from lower socioeconomic classes. There is mounting evidence that oxidative stress, specifically lipid peroxidation (LPO) contributes to the disease process. We investigated levels of LPO and its possible consequences for these patients.

MATERIAL/METHODS: Forty women aged 15-45 years who fulfilled the 1994 Centers for Disease Control’s diagnostic criteria for chronic fatigue syndrome (CFS) with no comorbidities were recruited and were age matched to a control group of 40 healthy women. Levels of total cholesterol (TC), triglycerides (TG), LDL cholesterol (LDLc), HDL cholesterol (HDLc), and malondialdehyde (MDA) levels were measured.

RESULTS: Although initial statistical analyses showed no differences between groups (P=.345), when subdivided according to the level of MDA, a difference was found in the subgroup of high-level MDA (P=.034). There was a negative correlation between HDLc and MDA levels (r=0.3; P=.046), a positive correlation between TG and MDA levels (r=0.4; P=.006), and lower levels of HDL cholesterol in the CFS group (P=.036).

CONCLUSIONS: High levels of MDA, positively correlated with TG and lower HDL levels, might be indicative of proatherogenic events in female CFS patients, a group not otherwise considered a risk for atherosclerosis.

 

Source: Brkic S, Tomic S, Maric D, Novakov Mikic A, Turkulov V. Lipid peroxidation is elevated in female patients with chronic fatigue syndrome. Med Sci Monit. 2010 Dec;16(12):CR628-32. https://www.ncbi.nlm.nih.gov/pubmed/21119582