The benefits of Vitamin D in the COVID-19 pandemic: biochemical and immunological mechanisms.

In December 2019, a new infectious complication called CoronaVirus Infectious Disease-19, briefly COVID-19, caused by SARS-COV-2, is identified in Wuhan, China. It spread all over the world and became a pandemic. In many individuals who had suffered SARS-COV-2 infection, cytokine storm starts through cytokine overproduction and leads to Acute Respiratory Syndrome (ARS), organ failure, and death. According to the obtained evidence, Vitamin D (VitD) enhances the ACE2/Ang(1-7)/MasR pathway activity, and it also reduces cytokine storms and the ARS risk. Therefore, VitD intake may be beneficial for patients with SARS-COV-2 infection exposed to cytokine storm but do not suffer hypotension. In the present review, we have explained the effects of VitD on the renin-angiotensin system (RAS) function and angiotensin-converting enzyme2 (ACE2) expression. Furthermore, we have reviewed the biochemical and immunological effects of VitD on immune function in the underlying diseases and its role in the COVID-19 pandemic.

Mechanisms of COVID-19 Entry into the Cell: Potential Therapeutic Approaches Based on Virus Entry Inhibition in COVID-19 Patients with Underlying Diseases.

The Coronavirus disease 2019 (COVID-19) virus spread from Wuhan, China, in 2019 and is spreading rapidly around the world. COVID-19 victims are almost associated with cardiovascular disease, high blood pressure, diabetes, and other underlying diseases. Concerning the high prevalence of these disorders, widespread mortality threatens global society, and its fatality rate may increase with increasing COVID-19 prevalence in countries with older populations. Therefore, evaluating patients' clinical status with severe COVID-19 infection and their medical history can help manage treatment. Currently, one of the considered treatments is angiotensin-converting enzyme 2 (ACE2) inhibition. This study investigated virus entry mechanisms through membrane receptors, their role in the pathogenesis of COVID-19 and underlying diseases, and treatment methods based on the viral entrance inhibition. According to existing studies, inhibition of ACE2 can increase oxidative stress, inflammation, fibrosis and ultimately exacerbate underlying diseases such as cardiovascular disease, kidney disease, diabetes, and hypertension in individuals with COVID-19. The ACE2 inhibition is not suitable for patients with COVID-19 with underlying diseases, but it seems that the recombinant ACE2 solution is more appropriate for inhibiting the virus in these patients if hypotension would be monitored.

High-intensity interval training (HIIT) alleviated NAFLD feature via miR-122 induction in liver of high-fat high-fructose diet induced diabetic rats.

Background: Exercise intervention is strongly recommended to manage metabolic diseases. In this study, we investigate, whether HIIT and CET can induce hepatic miR-122 expression, NAFLD rats with diabetes.Methods: 40 Wistar rats divided into 2 groups, non-diabetic (NDC) and diabetic .Type 2 diabetes was induced by high-fat high-fructose diet (HFHFD). Then diabetic rats were subdivided into three groups: diabetic control (HFHFD + DC), CET (HFHFD + CET), and HIIT (HFHFD + HIIT). After eight weeks of exercise on a rodent treadmill, we measured miR-122 and its target genes expression in the liver of rats.Results: HIIT decreased the expression of FAS, ACC, SREBP-1c compared with HFHFD + DC (p = .004, p = .032, p = .043, respectively), and could partially increase miR-122 expression as compared with HFHFD + DC (26.8%, p = .68).Conclusions: Exercise training could be a non-pharmacological intervention for improvement of NAFLD of diabetic rats by induction of miR-122. HIIT had a greater effect on NAFLD amelioration than CET.

High-intensity interval training (HIIT) effectively enhances heart function via miR-195 dependent cardiomyopathy reduction in high-fat high-fructose diet-induced diabetic rats.

Aims: Regarding the fact that up-regulation of miR-195 in diabetic hearts has a potential role in diabetic cardiomyopathy, the present study investigated whether continuous endurance training (CET) and high-intensity interval training (HIIT) reduces miR-195 expression and which exercise is effective in this regard.Methods: Diabetes was induced by high-fat high-fructose diet (HFHFD). Then, the rats were sub-divided into three categories; sedentary (HFHFD + SED), continuous endurance training (HFHFD + CET), and high-intensity interval training group (HFHFD + HIIT). After eight weeks of running, expression of miR-195 and myocardial function were evaluated.Results: HIIT effectively decreases the expression of miR-195 and increases the expression of Sirt1 and BCL-2 in diabetic rats compared with CET. Our results showed that HIIT compared with CET increases left ventricular ejection fraction (LVEF%) and fractional shortening (FS%).Conclusions: Our results indicated that exercise, especially HIIT is an appropriate strategy for reducing miR-195 and improving myocardial function in diabetic rats compared with CET.