The novel 2019 coronavirus, SARS-CoV-2 (COVID-19), emerged towards the end of 2019 in the city of Wuhan in the province of Hubei in the People's Republic of China, and it has spread to the entire world very fast and in a very short time. This study aimed to investigate the course of the pandemic by mathematical modelling based on the information that the time-dependent change (spreading) rate of the H number of individuals who have caught a contagious disease is proportional to the multiplication of the numbers of those who have caught the disease and those who have not. According to the results of the mathematical modelling in our study, in the case that sufficient precautions are not taken, or precautions are reduced, the course of the pandemic may show a very fast change in the negative direction. For this reason, every precaution, individual or social, will be significant in terms of the course of the COVID-19 pandemic.

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The TRPV1 channel is activated in neurons by capsaicin, oxidative stress, acidic pH and heat factors, and these factors are attenuated by the antioxidant role of calorie restriction (CR). Hence, we investigated the hypothesis that the antioxidant roles of CR and food frequency (FF) may modulate TRPV1 activity and apoptosis through inhibition of mitochondrial oxidative stress in hippocampal (HIPPON) and dorsal root ganglion neurons (DRGN). We investigated the contribution of FF and CR to neuronal injury and apoptosis through inhibition of TRPV1 in rats. We assigned rats to control, FF and FF + CR groups. A fixed amount of food ad libitum was supplemented to the control and FF groups for 20 weeks, respectively. FF + CR group were fed the same amount of food as the control group but with 20% less calories during the same period. In major results, TRPV1 currents, intracellular Ca levels, apoptosis, reactive oxygen species, mitochondrial depolarization, PARP-1 expression, caspase 3 and 9 activity and expression values were found to be increased in the HIPPON and DRGN following FF treatment, and these effects were decreased following FF + CR treatment. The FF-induced decrease in cell viability of HIPPO and DRGN, and vitamin E concentration of brain, glutathione peroxidase, vitamin A, and β-carotene values of the HIPPO, DRGN, plasma, liver and kidney were increased by FF + DR treatment, although lipid peroxidation levels in the same samples were decreased. In conclusion, CR reduces FF-induced increase of oxidative stress, apoptosis and Ca entry through TRPV1 in the HIPPON and DRGN. Our findings may be relevant to the etiology and treatment of obesity following CR treatment.

OBJECTIVE:In living organisms, there is a balance between the oxidant and antioxidant systems. Reactive products continuously formed by exogenous and endogenous sources are rendered harmless by the antioxidant system. Oxidative stress is an etiological factor in aging and the development of various diseases. In the present study, the aim was to investigate the effects of meal frequency and calorie restriction on oxidant-antioxidant systems in rat serum and tissue.METHODS:Nine adult male Wistar Albino rats were used for the pilot study, and another 24 adult male Wistar Albino rats, also weighing 200 to 250 g each, were included in the main study. The rats were divided into 3 groups based on nutrition: the ad libitum group (AL) (n=8), the 2-meal group (TM) (n=8), and the 2-meal with calorie restriction group (TM-CR) (n=8). Following the 4-week pilot study, nutrition regulation was performed in all groups for 20 weeks, 7 days a week, with 60 minutes allotted per meal. Serum and tissues of rats were isolated at the end of the experiment. Total antioxidant status (TAS) and total oxidant status (TOS) were determined using the Erel method. Oxidative stress index (OSI) was calculated using the formula OSI = TOS/TAS. Liver tissue was examined histopathologically. Statistical analyses were performed using the IBM SPSS Statistics for Windows, Version 20.0 (IBM Corp., Armonk, NY, USA) program.RESULTS:There were significant differences between the AL and TM, and the AL and TM-CR groups in adipose tissue TOS and OSI, and between the AL and TM groups in the liver TAS of the rats (p<0.05).CONCLUSION:Calorie restriction and sparse meal frequency can increase the activity of antioxidants and can reduce oxidative stress. Thus, many diseases caused by oxidative stress may be prevented with the correct regulation of feeding.