Alpha lipoic acid attenuates high-fructose-induced pancreatic toxicity.

Abstract

Chronic consumption of high-fructose corn syrup (HFCS) causes several problems such as insulin resistance. The goal of the study was to investigate pancreatic damage induced by chronic HFCS consumption and the protective effects of alpha lipoic acid (ALA) on pancreatic cells. Wistar Albino, 4-month-old, female rats weighing 250-300g were randomly distributed into three groups, each containing eight rats. The study included an HFCS group, an HFCS+ALA-administered group and a control group (CON). The prepared 30% solution of HFCS (F30) (24% fructose, 28% dextrose) was added to the drinking water for 10 weeks. ALA treatment was begun 4 weeks after the first HFCS administration (100mg/kg/oral, last 6 weeks). Rats were anaesthetised and euthanised by cervical dislocation 24h after the last ALA administration. Blood samples for biochemical tests (amylase, lipase, malondialdehyde (MDA) and catalase (CAT)) and tissue samples for histopathological and immunohistochemical examinations (caspase-3, insulin and glucagon) were collected. Comparing the control and HFCS groups, serum glucose (150.92±39.77 and 236.50±18.28, respectively, p<0.05), amylase (2165.00±150.76 and 3027.66±729.19, respectively, p<0.01), lipase (5.58±2.22 and 11.51±2.74, respectively, p<0.01) and pancreatic tissue MDA (0.0167±0.004 and 0.0193±0.006, respectively, p<0.05) levels were increased, whereas tissue CAT (0.0924±0.029 and 0.0359±0.023, respectively, p<0.05) activity decreased in the HFCS group significantly. Histopathological examination revealed degenerative and necrotic changes in Langerhans islet cells and slight inflammatory cell infiltration in pancreatic tissue in the HFCS group. Immunohistochemically there was a significant decrease in insulin (2.85±0.37 and 0.87±0.64, respectively, p<0.001) and glucagon (2.71±0.48 and 1.00±0.75, respectively, p<0.001) secreting cell scores, whereas a greater increase in caspase-3 (0.14±0.37 and 1.00±0.75, respectively, p<0.05) expression was seen in this group compared with the controls. In the ALA-treated group, all of these pathologic conditions were improved. This study indicated HFCS induced pancreatic lesions, but ALA had ameliorative effects.