The effects of prebiotic and probiotic combination on the liver in streptozotocin-induced diabetic rats

Diabetes is a common metabolic disease worldwide. The imbalances in gut microbiota homeostasis may be detrimental and gut microbiota dysbiosis may be involved in the pathogenesis of diabetes. The prebiotic and probiotic applications are substantial in the composition and functions of the intestinal microbiota. The effects of synbiotics, which are combinations of prebiotics and probiotics, on the pathogenesis of diabetes are not fully understood. This study aims to investigate the effects of a synbiotic, which is a combination of prebiotics and probiotics, on the liver in animals that are induced diabetes mellitus by the administration of streptozotocin (STZ). For our study, 32 2.5-month-old male rats were used as experimental animals. Animals were divided into 4 groups as Control, Diabetes, Diabetes+ Synbiotic and Synbiotic group. Animals that induced diabetes by administering STZ (60 mg/kg STZ) were treated with a synbiotic called Probien® for 28 days. The blood glucose levels and weights of the experimental animals were determined at one-week intervals from the beginning of the experiment to the end of the experiment. From the animals under anesthesia, blood was taken from the heart for biochemical analysis. In addition, the livers of animals were harvested for light microscopy and biochemical studies. The data were evaluated statistically. It was detected that blood glucose levels increased in the diabetic group treated with STZ compared to the control group, and body weights decreased at the end of the experiment. In this group, it has been observed that there was significant damage to the liver compared to the control, sinusoids enlarged, irregularities in the central vein endothelium, inflammation and increase in connective tissue in some portal areas. In addition, it was determined that the ALT value in the serum increased, while the AST value did not change. The reaction of iNOS, TNF-α and IL-6, MDA, TOS and OSI values increased in tissue, TAS and NO values did not change. In the diabetes+symbiotic group, the blood glucose values decreased by the 21st day and the body weight have increased at the end of the experiment. It has been determined that the application of synbiotic significantly decreased the tissue damage, however, there is still significant damage when compared to the control group. Also, it has been detected that ALT, AST and OSI values remain similar to that of the control group while iNOS, TNF-α and IL-6 reactions, MDA and TOS levels decreased, and that TAS and NO values remained unchanged. In the synbiotic group, it has been determined that blood glucose levels, body weights, AST, ALT, TAS, NO, MDA, TOS and OSI values were found to be similar to the control group. However, it has been detected that tissue damage and the increment in the iNOS, TNF-α and IL-6 reactions compared to the control group. In conclusion, in our study, synbiotic administration, which is a combination of probiotics and prebiotics, had effects on blood glucose and body weight in diabetes and also caused a decrease in inflammatory cytokines, oxidative stress and liver damage. Therefore, our findings show that synbiotic application may have effects on complications in diabetes.