Expression of miсroRNA-34, microRNA-130, microRNA-194 in the saliva of children with obesity

Obesity is a global issue increasingly affecting the pediatric population. Excess adipose tissue raises the risk of developing cardiovascular, oncological, metabolic, and immunological disorders. Beyond social, hormonal, and genetic causes, scientists are particularly focused on cellular and molecular aspects of the disease's development. Currently, there is an active search for new promising markers to predict the risk of obesity, with an emphasis on non-invasive methods, forming a basis for effective preventive medicine. Key factors in the development of obesity include intracellular protein kinases, inflammation mediators, oxidative stress components, gastrointestinal hormones, adipokines, angiopoietin-like proteins, and microRNAs. Objective. To study the features of microRNA-34a, microRNA-130, and microRNA-194 expression in the serum of children with obesity and identify the relationship with clinical and laboratory parameters of the disease. Materials and methods. A total of 90 children, aged 10 to 17 years, were examined. The primary group consisted of 60 children with overweight and obesity, while the comparison group included 30 healthy children. Anthropometric measurements were taken for all participants, calculating the standard deviation of the body mass index using WHO Anthro Plus. Blood analysis was conducted to determine levels of glucose, alanine aminotransferase, aspartate aminotransferase, triglycerides, total cholesterol, high-density lipoprotein, low-density lipoprotein, insulin, and leptin. Additionally, saliva analysis was performed to study microRNA. Body composition was assessed using the InBody 770 device. Statistical data processing was carried out using IBM SPSS Statistics 19.0.0, Russian version (USA). Results. The study revealed a decrease in microRNA-130 expression in the saliva of children with obesity, 1.1 (0.01; 2.93), compared to the control group, 72.6 (0.07; 215.7) (p=0.005). This expression level was associated with serum cholesterol levels (r=-0.87; p 0.05). Notably, microRNA-130 expression increased 19.3 times in the group of boys with obesity, 1.37 (1.37; 1.37), compared to the control group, 0.07 (0.07; 1.07) (p=0.005). Conversely, in girls with obesity, this indicator decreased 105.8 times compared to girls of normal weight (p=0.0001). Additionally, microRNA-194 expression increased 3.4 times in girls with obesity, 156.04 (156.04; 156.04), compared to the control group, 46.4 (46.4; 46.4) (p=0.004). Conclusions. The study of microRNA-34, microRNA-130, and microRNA-194 expression in the saliva of children with obesity revealed a decrease in microRNA-130 expression in children with obesity, differences in microRNA-130 expression between boys and girls with obesity, and an increase in microRNA-194 expression in girls with obesity. These findings suggest that changes in microRNA expression may be associated with the development of obesity in children, and the observed differences between boys and girls may indicate gender-specific regulation of microRNA expression in the context of obesity. These data highlight the importance of microRNAs as potential biomarkers that reflect changes occurring in pediatric obesity. Changes in microRNA-130 and microRNA-194 expression can serve as biomarkers of metabolic disorders and be used for early diagnosis and risk assessment of obesity and related diseases. Further research in this area may contribute to the development of new strategies for preventing and treating childhood obesity based on epigenetic regulatory mechanisms.