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.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide and affects nearly 30% of the adult population and 10% of the pediatric population. It is estimated that this number will double by 2030. MASLD is one of the leading causes of hepatocellular carcinoma, cirrhosis, and liver transplantation, as well as a significant risk factor for cardiovascular disease and mortality. Due to the ever-increasing number of patients, the long-term asymptomatic course of the disease, serious complications, and lack of preventive programs, as well as insufficient awareness of the disease among patients and doctors themselves, MASLD is a growing interdisciplinary problem and a real challenge for modern medicine. The main cause of MASLD is an inappropriate lifestyle—inadequate nutrition and insufficient physical activity, which lead to various components of metabolic syndrome. Lifestyle changes—appropriate diet, weight reduction, and systematic physical activity—are also the basis for the prevention and treatment of MASLD. Hence, in recent years, so much importance has been attached to lifestyle medicine, to non-pharmacological treatment as prevention of lifestyle diseases. The narrative review presents possible therapeutic options for non-pharmacological management in the prevention and treatment of MASLD. The best documented and available diets used in MASLD were discussed, focusing on the benefits and drawbacks of the Mediterranean, high-protein, ketogenic, and intermittent fasting diets. In addition, the most recent recommendations regarding physical activity are summarized.

Background. The aim of this study was to determine the effects of exposure to cold and heat on the activity of selected lysosomal enzymes as well as on the activity of the protease inhibitor, which are all considered to be markers of cellular damage. Material. Two groups of healthy volunteers were included in the study. The first group consisted of experienced winter swimmers who practiced bathing in ice-cold water once a week, while the other group was comprised of persons who had never taken part in winter swimming before. During the experiment all the participants bathed in a river with a water temperature of 0°C. The same volunteers were later subjected to a sauna bath at an air temperature of 85°C. Methods. The activity of cathepsin D, alpha-1-antitrypsin, arylsulphatase and acid phosphatase was measured in the participant's blood serum. Results. After exposure to cold water no changes in the parameters studied could be found. However, after the sauna an increase in the activity of arylsulphatase and alfa-1-antitrypsin accompanied by a decrease of cathepsin D activity could be observed. Conclusions. Winter swimming seems to have no effect on the activity of the lysosomal enzymes. By contrast, an increase of certain lysosomal enzymes after the sauna suggests that it may be deleterious to the lysosomal membranes. Furthermore it seems that regular winter swimming combined with sauna, according to hormesis theory, induces some adaptive response.

Metabolic syndrome (MetS) and erratic eating patterns are associated with circadian rhythm disruption which contributes to an increased cardiometabolic risks. Restricting eating period (time-restricted eating, TRE) can restore robust circadian rhythms and improve cardiometabolic health. We describe a protocol of the Time-Restricted Eating on Metabolic and Neuroendocrine homeostasis, Inflammation, and Oxidative Stress (TREMNIOS) pilot clinical trial in Polish adult patients with MetS and eating period of ≥14 h/day. The study aims to test the feasibility of TRE intervention and methodology for evaluating its efficacy for improving metabolic, neuroendocrine, inflammatory, oxidative stress and cardiac biomarkers, and daily rhythms of behavior for such population. Participants will apply 10-h TRE over a 12-week monitored intervention followed by a 12-week self-directed intervention. Changes in eating window, body weight and composition, biomarkers, and rhythms of behavior will be evaluated. Dietary intake, sleep, activity and wellbeing will be monitored with the myCircadianClock application and questionnaires. Adherence to TRE defined as the proportion of days recorded with app during the monitored intervention in which participants satisfied 10-h TRE is the primary outcome. TREMNIOS will also provide an exploratory framework to depict post-TRE changes in cardiometabolic outcomes and behavior rhythms. This protocol extends previous TRE-related protocols by targeting European population with diagnosed MetS and including long-term intervention, validated tools for monitoring dietary intake and adherence, and comprehensive range of biomarkers. TREMNIOS trial will lay the groundwork for a large-scale randomized controlled trial to determine TRE efficacy for improving cardiometabolic health in MetS population.

Metabolic syndrome (MetS) and a prolonged daily eating window (EW) are associated with circadian rhythm disruption and increased cardiometabolic risk. Misalignment between circadian timing system and daily rhythms of food intake adversely impacts metabolic regulatory mechanisms and cardiovascular function. Restricting the daily EW by imposing an eating–fasting cycle through time-restricted eating (TRE) can restore robust circadian rhythms, support cellular metabolism, and improve cardiometabolic health. The aim of this study was to assess a feasibility of 12-week TRE intervention with self-selected 10 h EW and effects of TRE on EW duration, cardiometabolic outcomes, daily rhythms of behavior, and wellbeing in Polish patients with MetS and EW ≥ 14 h/day. Dietary intake was monitored with a validated myCircadianClock application (mCC app). Adherence to TRE defined as the proportion of days recorded with mCC app in which participants satisfied 10-h TRE was the primary outcome. A total of 26 patients (aged 45 ± 13 years, 62% women, 3.3 ± 0.5 MetS criteria, EW 14 ± 1.5 h/day) were enrolled. Coexistence of increased waist circumference (WC) (96% of patients), elevated fasting plasma glucose (FPG) (77%), and elevated blood pressure (BP) (69%) was the most common MetS pattern (50%). TRE intervention (mean duration of 81.6 ± 12.6 days) led to reducing daily EW by 28% (p < 0.0001). Adherence to TRE was 87 ± 13%. Adherence to logging food intake on mCC app during TRE was 70 ± 27%. Post TRE, a decrease in body weight (2%, 1.7 ± 3.6 kg, p = 0.026), body mass index (BMI) (1%, 0.5 ± 1.2 kg/m², p = 0.027), WC (2%, 2.5 ± 3.9 cm, p = 0.003), systolic BP (4%, 4.8 ± 9.0 mmHg, p = 0.012), FPG (4%, 3.8 ± 6.9 mg/dL, p = 0.037), glycated hemoglobin (4%, 0.2 ± 0.4%, p = 0.011), mean fasting glucose level from continuous glucose monitor (CGM) (4%, 4.0 ± 6.1 mg/dL, p = 0.002), and sleepiness score (25%, 1.9 ± 3.2 points, p = 0043) were observed. A significant decrease in body weight (2%), BMI (2%), WC (3%), mean CGM fasting glucose (6%), sleepiness score (27%), and depression score (60%) was found in patients with mean post-TRE EW ≤ 10 h/day (58% of total), and not in patients with EW > 10 h/day. Adherence to TRE was higher in patients with post-TRE EW ≤ 10 h/day vs. patients with EW > 10 h/day (94 ± 6% vs. 77 ± 14%, p = 0.003). Our findings indicate that 10-h TRE was feasible in the European MetS population. TRE resulted in reducing daily EW and improved cardiometabolic outcomes and wellbeing in patients with MetS and prolonged EW. Use of the mCC app can aid in implementing TRE. This pilot clinical trial provides exploratory data that are a basis for a large-scale randomized controlled trial to determine the efficacy and sustainability of TRE for reducing cardiometabolic risks in MetS populations. Further research is needed to investigate the mechanisms of TRE effects, including its impact on circadian rhythm disruption.

Background: COVID-19 vaccines induce a differentiated humoral and cellular response, and one of the comparable parameters of the vaccine response is the determination of IgG antibodies. Materials and Methods: Concentrations of IgG anti-SARS-CoV-2 antibodies were analyzed at three time points (at the beginning of May, at the end of June and at the end of September). Serum samples were obtained from 954 employees of the Nicolaus Copernicus University in Toruń (a total of three samples each were obtained from 511 vaccinated participants). IgG antibody concentrations were determined by enzyme immunoassay. The statistical analysis included comparisons between vaccines, between convalescents and COVID-19 non-patients, between individual measurements and included the gender, age and blood groups of participants. Results: There were significant differences in antibody levels between mRNA and vector vaccines. People vaccinated with mRNA-1273 achieved the highest levels of antibodies, regardless of the time since full vaccination. People vaccinated with ChAdOx1 nCoV-2019 produced several times lower antibody levels compared to the mRNA vaccines, while the antibody levels were more stable. In the case of each of the vaccines, the factor having the strongest impact on the level and stability of the IgG antibody titers was previous SARS-CoV-2 infection. There were no significant correlations with age, gender and blood type. Summary: mRNA vaccines induce a stronger humoral response of the immune system with the fastest loss of antibodies over time.