Smallanthus sonchifolius (yacon) roots improve the damage induced by oxidative stress in the diabetic intestine

GOMEZ ROJAS J.; SÁNCHEZ S.S.; HONORÉ S.M.

Salta, Argentina

Congreso; Joint LV Annual SAIB Meeting and XIV PABMB Congress; 2019

Argentine Society of Biochemical Research (SAIB) and Panamerican Association of Biochemistry and Molecular Biology (PABMB)

Diabetes mellitus is becoming an increasingly prevalent disease with acute and chronic complications. Gastrointestinal symptoms associated with diabetes, known as diabetic enteropathy, are dyspepsia, constipation, diarrhea, and fecal incontinence. Previous findings indicate that hyperglycemia and the resulting oxidative stress on neural networks, including interstitial cells of Cajal, play a central role in the development of diabetic enteropathy. Nowadays, non-pharmacologic treatment options to manage these complications are becoming relevant. Smallanthus sonchifolius (yacon) is an Andean crop tuber characterized by its low caloric value and high fiber content, with a low glycemic response that makes it appropriate for consumption by diabetic individuals. In the present work, we investigate the effect of the yacon flour, rich in fructooligosaccharides (FOS) and phenolic compounds, in the intestine of diabetic rats. Diabetes was induced in male Wistar rats, using a single intraperitoneal dose (50 mg/kg bw) of streptozotocin (STZ). The rats were randomly assigned in the following groups (n = 6 animals/group): control, control supplemented with yacon flour (340 mg FOS/kg bw, Control+Y), diabetic (STZ), and STZ supplemented with yacon (340 mg FOS/kg bw, STZ+Y). Clinical, biochemical, molecular parameters were evaluated, and histological studies of intestinal tissue were performed. The results were analyzed statistically (t-test and ANOVA/post hoc test) considering a value of p < 0.05. Administration of yacon for 4 weeks did not change the levels of glucose, insulin, total cholesterol, and HDLc in STZ+Y animals. However, triglyceride and VLDLc levels were significantly reduced in this group. Clinically, the STZ+Y animals maintained their body and intestine weight, while the cecum presented marked hypertrophy. From a functional point of view, gastrointestinal transit increased significantly, accompanied by variations in the expression of intestinal peptides, with an increase in substance P and a decrease in the vasoactive intestinal polypeptide. Histological analysis revealed that the consumption of yacon prevents structural disorders of the intestine, particularly at the level of nerve plexuses. The inflammatory state decreased both systemically and in intestinal tissue in animals that received yacon. The redox balance was restored in the STZ+Y group showing a decreased lipid peroxidation and increased antioxidant enzymes activity. These results lead us to conclude that the consumption of yacon roots prevents the development of structural and functional alterations in the intestine of diabetic rodents, improving the inflammatory state and restoring redox balance, showing the potentiality of these roots in diabetes management.