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1.
Melatonin: Roles in influenza, Covid-19, and other viral infections.
Anderson, G, Reiter, RJ
Reviews in medical virology. 2020;30(3):e2109
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Viruses like influenza and coronaviruses change quickly, making it challenging to develop effective treatments and vaccines in a short time frame. Consequently, the use of generic substances that limit viral effects are of high interest. In this paper, the authors summarize a range of mechanisms in which melatonin can alter the impact of virus infections and infection-associated inflammatory overdrive aka cytokine storm. Melatonin, the sleep hormone, is well known for its potent antioxidant and anti-inflammatory action. It seems highly likely that melatonin can modulate the cellular function of all cells, mostly via mitochondrial function. This is particularly relevant in immune cells. For example, the daytime variance in immune function seems to be closely linked with mitochondrial activity and energy production. Other relevant mechanisms described are the antiviral role of melatonin-induced sirtuins - proteins that regulate cellular health-, the impact of viruses on cell coordinating microRNA, the role of the gut microbiome and gut permeability, as well as sympathetic nervous system activation and the protective effects of parasympathetic activation. Also considered are pre-existing health conditions and conditions that are linked with a decline in melatonin along with ageing, all being groups in which severity of viral infections is felt. This paper may be of interest to those who like to explore in more depth the mechanisms behind melatonin and its ability to influence viral disease progression.
Abstract
There is a growing appreciation that the regulation of the melatonergic pathways, both pineal and systemic, may be an important aspect in how viruses drive the cellular changes that underpin their control of cellular function. We review the melatonergic pathway role in viral infections, emphasizing influenza and covid-19 infections. Viral, or preexistent, suppression of pineal melatonin disinhibits neutrophil attraction, thereby contributing to an initial "cytokine storm", as well as the regulation of other immune cells. Melatonin induces the circadian gene, Bmal1, which disinhibits the pyruvate dehydrogenase complex (PDC), countering viral inhibition of Bmal1/PDC. PDC drives mitochondrial conversion of pyruvate to acetyl-coenzyme A (acetyl-CoA), thereby increasing the tricarboxylic acid cycle, oxidative phosphorylation, and ATP production. Pineal melatonin suppression attenuates this, preventing the circadian "resetting" of mitochondrial metabolism. This is especially relevant in immune cells, where shifting metabolism from glycolytic to oxidative phosphorylation, switches cells from reactive to quiescent phenotypes. Acetyl-CoA is a necessary cosubstrate for arylalkylamine N-acetyltransferase, providing an acetyl group to serotonin, and thereby initiating the melatonergic pathway. Consequently, pineal melatonin regulates mitochondrial melatonin and immune cell phenotype. Virus- and cytokine-storm-driven control of the pineal and mitochondrial melatonergic pathway therefore regulates immune responses. Virus-and cytokine storm-driven changes also increase gut permeability and dysbiosis, thereby suppressing levels of the short-chain fatty acid, butyrate, and increasing circulating lipopolysaccharide (LPS). The alterations in butyrate and LPS can promote viral replication and host symptom severity via impacts on the melatonergic pathway. Focussing on immune regulators has treatment implications for covid-19 and other viral infections.
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How Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Progresses: The Natural History of ME/CFS.
Nacul, L, O'Boyle, S, Palla, L, Nacul, FE, Mudie, K, Kingdon, CC, Cliff, JM, Clark, TG, Dockrell, HM, Lacerda, EM
Frontiers in neurology. 2020;11:826
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A good understanding of the disease course is vital not only for the design of preventative and intervention studies, but also to assess the timing and type of intervention that minimizes disease risk or optimizes prognosis. The aim of this review was to explore the long-term course of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and how presentation and pathophysiological abnormalities may vary with time. Literature shows that it is unknown how the initial host response to a stressor or insult compares in individuals who do or do not develop typical symptoms of ME/CFS. However, the return to good health, following exposure to mild or moderate levels of insult, seems to be impeded in ME/CFS when symptoms persist for longer than 3–6 months. Authors sought to provide a simple framework, similar to those of other chronic diseases, in an effort to extend the temporal perception of ME/CFS and better incorporate the less defined pre-illness stages of the disease. In fact, they conclude that by applying this framework to ME/CFS research efforts could better elucidate the pathophysiological mechanisms of the disease and identify potential therapeutic targets at distinct stages.
Abstract
We propose a framework for understanding and interpreting the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) that considers wider determinants of health and long-term temporal variation in pathophysiological features and disease phenotype throughout the natural history of the disease. As in other chronic diseases, ME/CFS evolves through different stages, from asymptomatic predisposition, progressing to a prodromal stage, and then to symptomatic disease. Disease incidence depends on genetic makeup and environment factors, the exposure to singular or repeated insults, and the nature of the host response. In people who develop ME/CFS, normal homeostatic processes in response to adverse insults may be replaced by aberrant responses leading to dysfunctional states. Thus, the predominantly neuro-immune manifestations, underlined by a hyper-metabolic state, that characterize early disease, may be followed by various processes leading to multi-systemic abnormalities and related symptoms. This abnormal state and the effects of a range of mediators such as products of oxidative and nitrosamine stress, may lead to progressive cell and metabolic dysfunction culminating in a hypometabolic state with low energy production. These processes do not seem to happen uniformly; although a spiraling of progressive inter-related and self-sustaining abnormalities may ensue, reversion to states of milder abnormalities is possible if the host is able to restate responses to improve homeostatic equilibrium. With time variation in disease presentation, no single ME/CFS case description, set of diagnostic criteria, or molecular feature is currently representative of all patients at different disease stages. While acknowledging its limitations due to the incomplete research evidence, we suggest the proposed framework may support future research design and health care interventions for people with ME/CFS.
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The Functional Medicine Approach to COVID-19: Nutrition and Lifestyle Practices for Strengthening Host Defense.
Minich, DM, Hanaway, PJ
Integrative medicine (Encinitas, Calif.). 2020;19(Suppl 1):54-62
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Lifestyle interventions can be an effective means to help patients regain their locus of control during times of uncertainty like those experienced in a pandemic. The study is a review about emerging research focusing on nutrition and lifestyle practices for strengthening host defense. Research indicates that there are three mechanisms that may be involved in the ability of food-derived compounds to reduce viral infection and severity: a. balancing inflammatory pathways, b. reducing oxidative stress and increasing antioxidant levels, and c. harmonizing the gut microbiome. Clinical recommendations focus mainly on nutrition, stress reduction/management, sleep quality and quantity, physical activity programme and social factors/connections. Authors conclude by emphasising that the findings of this study are only intended to identify lifestyle practices that may boost the immune system as they have not been proven effective against COVID-19.
Abstract
The developing symptoms of COVID-19, as well as the progression of illness and fatality, are a clearly a function of the overall health status of the individual. Complex, chronic diseases such as obesity, hypertension, and diabetes are directly correlated with risk of disease severity and mortality. We explore lifestyle interventions that have specifically been demonstrated to strengthen host defense, reduce the probability and mitigate the severity of viral infection. Lifestyle interventions, from a Functional Medicine perspective, include nutrition, sleep, exercise, stress reduction, and connection. These factors, when in balance, provide a foundation for optimal health and immune function.
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A Large Randomized Trial: Effects of Mindfulness-Based Stress Reduction (MBSR) for Breast Cancer (BC) Survivors on Salivary Cortisol and IL-6.
Lengacher, CA, Reich, RR, Paterson, CL, Shelton, M, Shivers, S, Ramesar, S, Pleasant, ML, Budhrani-Shani, P, Groer, M, Post-White, J, et al
Biological research for nursing. 2019;21(1):39-49
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Breast cancer survivors (BCS) often experience physiological and psychological stressors related to their diagnosis and treatment, and a disruption of cortisol function can affect cancer risk and progression. Increased levels of the stress hormone cortisol and interleukin-6 (IL-6), a pro-inflammatory immune mediator, have been associated with acute and chronic stress levels. Mindfulness-Based Stress Reduction (MBSR) is a clinical stress-reducing program, which has been found to decrease psychological and physical symptoms associated with stress. The purpose of this randomised study, involving 299 BCS, was to evaluate the efficacy of MBSR in reducing cortisol and IL-6 levels, compared to a usual-care control treatment. Statistically significant reductions in cortisol levels were seen after the delivery of the MBSR program at both time points (week 1 and 6), and at week 6 only for IL-6. There was no significant difference in change in cortisol or IL6 levels over time between the MBSR and the usual-care groups. An association was observed between levels of IL-6 and psychological and physical symptoms and quality of life, but not for cortisol. The authors conclude that MBSR can alleviate the stress response in the short term for breast cancer survivors.
Abstract
Breast cancer survivors (BCS) often experience psychological and physiological symptoms after cancer treatment. Mindfulness-based stress reduction (MBSR), a complementary and alternative therapy, has reduced subjective measures of stress, anxiety, and fatigue among BCS. Little is known, however, about how MBSR affects objective markers of stress, specifically the stress hormone cortisol and the pro-inflammatory cytokine interleukin-6 (IL-6). In the present study, BCS ( N = 322) were randomly assigned to a 6-week MBSR program for BC or usual-care control. Measurements of cortisol, IL-6, symptoms, and quality of life were obtained at orientation and 6 weeks. Cortisol and IL-6 were also measured prior to and after the MBSR(BC) class Weeks 1 and 6. The mean age of participants was 56.6 years and 69.4% were White non-Hispanic. Most had Stage I (33.8%) or II (35.7%) BC, and 35.7% had received chemotherapy and radiation. Cortisol levels were reduced immediately following MBSR(BC) class compared to before the class Weeks 1 and 6 (Wilcoxon-signed rank test; p < .01, d = .52-.56). IL-6 was significantly reduced from pre- to postclass at Week 6 (Wilcoxon-signed rank test; p < .01, d = .21). No differences were observed between the MBSR(BC) and control groups from baseline to Week 6 using linear mixed models. Significant relationships with small effect sizes were observed between IL-6 and both symptoms and quality of life in both groups. Results support the use of MBSR(BC) to reduce salivary cortisol and IL-6 levels in the short term in BCS.
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5.
The Sleep-Immune Crosstalk in Health and Disease.
Besedovsky, L, Lange, T, Haack, M
Physiological reviews. 2019;99(3):1325-1380
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The interaction between sleep and immunity is an established phenomena. This thorough review article summarises sleep changes in response to both infectious and non-infectious immune system challenges and describes the role of sleep in supporting the immune system. Details are provided of how sleep affects the innate immune system (first line, rapid defence against infection) as well as the adaptive immune system (second line, delayed defence against infection), using a feedback system which promotes host defence. Sleep is associated with reduced infection risk and can improve infection outcome and vaccination responses. Sleep deprivation is also associated with chronic, low-grade inflammation. Nutrition Practitioners wishing to support immunity can focus on sleep as a simple lifestyle measure to enhance resilience.
Abstract
Sleep and immunity are bidirectionally linked. Immune system activation alters sleep, and sleep in turn affects the innate and adaptive arm of our body's defense system. Stimulation of the immune system by microbial challenges triggers an inflammatory response, which, depending on its magnitude and time course, can induce an increase in sleep duration and intensity, but also a disruption of sleep. Enhancement of sleep during an infection is assumed to feedback to the immune system to promote host defense. Indeed, sleep affects various immune parameters, is associated with a reduced infection risk, and can improve infection outcome and vaccination responses. The induction of a hormonal constellation that supports immune functions is one likely mechanism underlying the immune-supporting effects of sleep. In the absence of an infectious challenge, sleep appears to promote inflammatory homeostasis through effects on several inflammatory mediators, such as cytokines. This notion is supported by findings that prolonged sleep deficiency (e.g., short sleep duration, sleep disturbance) can lead to chronic, systemic low-grade inflammation and is associated with various diseases that have an inflammatory component, like diabetes, atherosclerosis, and neurodegeneration. Here, we review available data on this regulatory sleep-immune crosstalk, point out methodological challenges, and suggest questions open for future research.
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Pharmaceutical Interventions in Chronic Fatigue Syndrome: A Literature-based Commentary.
Richman, S, Morris, MC, Broderick, G, Craddock, TJA, Klimas, NG, Fletcher, MA
Clinical therapeutics. 2019;41(5):798-805
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Myalgic encephalomyelitis, also known as Chronic Fatigue Syndrome (ME/ CFS), is a disease characterized by an inability to exert oneself physically, often coupled with a combination of other symptoms, including sleep disorders, severe unpredictable pain, and compromised cognitive abilities. The aim of this review was to delineate a number of the more prominent treatments for ME/CFS into different categories and evaluate the methods and results of corresponding drug trials. Results indicate that: • antiviral drugs appear to show limited efficacy in treating ME/CFS over a broad demographic. • there is a lack of clinical research focusing on the use of specific cyclooxygenase-2 inhibitors [analgesic] to treat ME/CFS. • antidepressants may be of use in delivering improvements in the quality of life of patients with ME/CFS. • recalibration of endocrine-immune regulation may be involved in supporting the persistence of ME/CFS and may be responsible at least in part for its resistance to single agent interventions. Authors conclude that there is a great need for larger, longitudinal studies focused on a more clearly defined subset of ME/CFS as well as a greater consideration of potential synergies between interventions and the suitability of combination therapies.
Abstract
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disorder characterized by prolonged periods of fatigue, chronic pain, depression, and a complex constellation of other symptoms. Currently, ME/CFS has no known cause, nor are the mechanisms of illness well understood. Therefore, with few exceptions, attempts to treat ME/CFS have been directed mainly toward symptom management. These treatments include antivirals, pain relievers, antidepressants, and oncologic agents as well as other single-intervention treatments. Results of these trials have been largely inconclusive and, in some cases, contradictory. Contributing factors include a lack of well-designed and -executed studies and the highly heterogeneous nature of ME/CFS, which has made a single etiology difficult to define. Because the majority of single-intervention treatments have shown little efficacy, it may instead be beneficial to explore broader-acting combination therapies in which a more focused precision-medicine approach is supported by a systems-level analysis of endocrine and immune co-regulation.
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Melatonin Supplementation Lowers Oxidative Stress and Regulates Adipokines in Obese Patients on a Calorie-Restricted Diet.
Szewczyk-Golec, K, Rajewski, P, Gackowski, M, Mila-Kierzenkowska, C, Wesołowski, R, Sutkowy, P, Pawłowska, M, Woźniak, A
Oxidative medicine and cellular longevity. 2017;2017:8494107
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Obesity is one of the major global health problems. Melatonin is a hormone which regulates wakefulness, functions as an antioxidant and plays a role in the immune system. Previous research suggests that melatonin deficiency is associated with obesity. The aim of this study was to estimate the effect of melatonin on oxidative stress and levels of cell signalling proteins released by fat cells (adipokines) in obese patients on a calorie-restricted diet. Thirty obese patients were supplemented with a daily dose of 10 mg of melatonin or placebo for 30 days with a calorie-restricted diet. Blood levels of melatonin, adipokines and markers of oxidative stress were measured at baseline and after supplementation. Significant body weight reduction (7%) was observed only in the melatonin group. After melatonin supplementation, the adiponectin and omentin-1 levels and glutathione peroxidase activities statistically increased, whereas the malondialdehyde concentrations were reduced. In the placebo group, a significant rise in 4-hydroxynonenal and a drop in the melatonin concentrations were found. The results show evidence of increased oxidative stress accompanying calorie restriction. The authors concluded that melatonin supplementation facilitated body weight reduction, improved the antioxidant defence, and regulated adipokine secretion. The findings suggest that melatonin should be considered in the management of obesity.
Abstract
Obesity is one of the major global health problems. Melatonin deficiency has been demonstrated to correlate with obesity. The aim of the study was to estimate the effect of melatonin on oxidative stress and adipokine levels in obese patients on a calorie-restricted diet. Thirty obese patients were supplemented with a daily dose of 10 mg of melatonin (n = 15) or placebo (n = 15) for 30 days with a calorie-restricted diet. Serum levels of melatonin, 4-hydroxynonenal (HNE), adiponectin, omentin-1, leptin, and resistin, as well as erythrocytic malondialdehyde (MDA) concentration and Zn/Cu-superoxide dismutase, catalase, and glutathione peroxidase (GPx) activities, were measured at baseline and after supplementation. Significant body weight reduction was observed only in the melatonin group. After melatonin supplementation, the adiponectin and omentin-1 levels and GPx activities statistically increased, whereas the MDA concentrations were reduced. In the placebo group, a significant rise in the HNE and a drop in the melatonin concentrations were found. The results show evidence of increased oxidative stress accompanying calorie restriction. Melatonin supplementation facilitated body weight reduction, improved the antioxidant defense, and regulated adipokine secretion. The findings strongly suggest that melatonin should be considered in obesity management. This trial is registered with CTRI/2017/07/009093.