Effects of parenteral supplementation of antioxidant minerals and vitamins in liver NF-κB activity and insulin-signaling of dairy cattle during the transition period

ANGELI E; SCHNEIDER A; MATILLER V; REY F; ORTEGA HH; HEIN GJ

Mar del Plata

Congreso; LXVIII Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica (SAIC); 2023

SAIC

The transition period (last 3 weeks of prepartum until 3 weeks postpartum)is the most critical stage in the lactation of dairy cows, characterized by a proinflammatorystate, oxidative stress and insulin resistance. The aim of this study was toevaluate the effects of parenteral vitamin and mineral supplementation on thehepatic insulin signaling pathway, a relevant proinflammatory factor in theliver, and systemic antioxidant enzymes in cows during the transition period. Thesupplemented group (SG; n = 11) received injections of 5 ml of the vitaminsupplement ADAPTADOR® Vit and 5 ml of the mineral supplement ADAPTADOR® Min(Biogenesis Bagó, Bs. As.; vitamin A palmitate 3.5% and vitamin E acetate 5%,copper edetate 1%, zinc edetate 4%, manganese edetate 1% and sodium selenite0.5%) on -60, -30 and 7 days relative to calving. The control group (CG; n =11) received two injections of 5 ml of 0.9 % sodium chloride solution. Wholeblood with heparin was used to measure superoxide dismutase (SOD) and glutathioneperoxidase (GSH-Px) activities by commercial kits, following the manufacturer'sinstructions (RANSOD and RANSEL, Randox Laboratories Ltd., Crumlin, UK). The liver protein expression of insulin receptor (IR), insulinreceptor substrate 1 (IRS-1), protein kinase B (also known as Akt), nuclear factor-κB(NF-κB), and their phosphorylated forms were analyzed byWestern blot. Resultsshowed that the GSH-Px activity was higher in the SG than in the CG (P <0.05). No differences between groups were observed in SOD activity (P >0.05). The activation of NF-κB was higher in SG than in CG (P < 0.05). Nodifferences between groups were observed in the insulin signaling components (P> 0.05). These results suggest that the vitamin and mineral supplementationprovided to dairy cows had beneficial effects on the antioxidant system andliver inflammatory state during the transition period.