(P07-001-24) Effect of Biofortified Cowpea on Iron Bioavailability, and Oxidative Stress in Rats Fed High-Fat/High-Sugar Diet

Objectives: To evaluate the effects of biofortified cowpea (Vigna unguiculata L. Walph) on iron bioavailability, and oxidative stress in rats fed with a high-fat/high-sugar diet (HFHS).

Methods: One conventional (BRS Pajeu) and two biofortified cowpea cultivars (BRS Tumucumaque and BRS Arace) were used and iron, phytate, and tannin composition were analyzed. In the depletion phase (21 days), 12 male Wistar rats received a normal diet, and 48 rats received the high-fat/high-sugar diet (HFHS), both iron-free diet. In the repletion phase (35 days) the animals were divided (n=12): normal diet + ferrous sulfate (NS), HFHS + ferrous sulfate (HS), HFHS + Pajeu (HP), HFHS + Tumucumaque (HT), and HFHS + Arace (HA), containing 12 ppm iron. Hemoglobin gain, hemoglobin regeneration efficiency (HRE), and relative biological value (RBV) were analyzed. Catalase, superoxide dismutase (SOD), nitric oxide (NO) and total antioxidant capacity (TAC) were quantified in the liver. The data were subjected to ANOVA followed by the Tukey test (p < 0.05). The project was approved by the Ethics Committee (protocol 013/2022).

Results: The cowpeas had no detected tannins, and similar contents of phytate. Pajeu had lowest values of iron (48.61mg/kg) than biofortified cowpeas Tumucumaque (67.17mg/kg) and Arace (68.21 mg/kg), consequently, Pajeu showed higher Phytate:Fe molar ratio (17.97) than Tumucumaque (12.89) and Arace (12.47). The HFHS reduced hemoglobin gain (NS=5.78±0.97a, HS=4.59±0.89b, HP=3.18±0.62c, HT=3.59±0.88bc, HA=4.21±0.88b), however the iron bioavailability indexes (HRE and RBV) showed higher values, with emphasis on Arace. Concerning the markers of oxidative stress, biofortified cowpeas increased TAC (NS=471.13±34.70a, HS=354.82±35.71b, HP=370.50±41.44b, HT=450.19±38.06a, HA=472.17±34.42a), and the biofortified cowpea Arace showed higher levels of NO and SOD.

Conclusions: Arace biofortified cowpea stood out in partially reverse the reduction of iron bioavailability, caused by the high-fat/high-sugar diet, which may be related to lower Phytate:Fe molar ratio, and improved the oxidative stress, caused by the HFHS diet.

Funding Sources: FAPES