(P06-043-25) Effect of Iron-Biofortified Cowpea on Hepcidin Level, Inflammation, and Oxidative Stress in Adipose Tissue in Rats Fed High-Fat/High-Sugar Diet

Objectives: To evaluate the effect of iron-biofortified and conventional cowpea beans (Vigna unguiculata L. Walp) on hepcidin level, inflammation, and oxidative stress in adipose tissue in rats fed high-fat/high-sugar diet (HFHS).

Methods: The iron-biofortified cowpeas (BRS Aracê and BRS Tumucumaque) and the conventional (BRS Pajeú) were cooked in pressure pan with deionized water (1:2, w:v), freeze-dried, and ground to produce flours. For the in vivo study, during 21 days (depletion phase), 12 young male Wistar rats received an iron-free normocaloric diet (N), and 48 rats received a diet free of iron and rich in fat and sugar (HFHS). Then, in the repletion phase (35 days), animals were divided into five groups (n=12): NF (N+ ferrous sulfate - FS); (HFHS+FS); HA (HFHS+Aracê); HT (HFHS+Tumucumaque); and HP (HFHS+Pajeú), containing 12 ppm iron. Hepcidin level was determined by Elisa kit (Invitrogen®) in the liver. Total antioxidant capacity (TAC), nitric oxide, superoxide dismutase (SOD), and catalase were determined in the adipose tissue. The area and presence of inflammatory infiltrate were analyzed in histological slides of adipose tissue stained with eosin/hematoxylin. The project was approved by CEUA/UFES (protocol n. 013/2022). Data were analyzed by ANOVA and post-hoc Tukey (p < 0.05).

Results: High-fat/high-sugar diet increased hepcidin level, but the cowpeas did not alter hepcidin levels (p>0.05). Regarding oxidative stress in adipose tissue, SOD, and catalase were similar between groups. High-fat/high-sugar diet reduced total antioxidant capacity, but the cowpeas were not able to reverse this reduction. Nitric oxide levels in the Tumucumaque group were lower than in the Pajeú group (p < 0.05). High-fat/high-sugar diet increased adipocyte area, and HP and HT groups presented smaller adipocyte areas than the others (p < 0.05). The presence of inflammatory infiltrate in adipose tissue was similar in the groups.

Conclusions: The iron-biofortified cowpeas did not influence oxidative stress and inflammation in adipose tissue and did not alter hepcidin levels in rats fed a high-fat/high-sugar diet. However, the Aracê and Pajeú cowpeas reduced the adipocyte area caused by the consumption of a high-fat/high-sugar diet. Therefore, the cowpea showed a beneficial effect on adipose tissue regardless of iron biofortification.

Funding Sources: FAPES