Evaluation of enzymes and metabolites related to lipids and ketone bodies in dairy cows with follicular persistence

CATTANEO MOREYRA ML; GAREIS NC; HEIN GJ; ANGELI E; ORTEGA HH; SALVETTI NR; RODRIGUEZ FM; REY F

Mar del Plata

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

SAIC

Reproduction can be negatively affected due to disruption in lip-id and ketone body metabolism. Therefore, we evaluate, by im-munohistochemistry, the protein expression of PPARγ receptor, acetyl-CoA carboxylase (ACC, fatty acid synthesis enzyme), and relevant enzymes of cholesterol metabolism and ketone bod-ies (3-hydroxy-3-methyl-glutaryl-coenzyme A reductase <HMGR and synthase <HMGS; succinyl-CoA:3-ketoacid CoA transferase <SCOT). In addition, we measured the concentrations of β-hy-droxybutyrate (BHB), non-esterified fatty acids (NEFA), cholesterol (CHOL) and triglycerides (TG) by using commercial kits. Cows with healthy reproductive tract (n=25) were subjected to estrous cycle synchronization with a G6G-Ovsynch protocol. While cows from the control group (C; n= 5) were only synchronized, those from the per-sistence groups were treated with progesterone intravaginally (P4) to induce follicles with 0 (P0; n=5), 5 (P5; n=5), 10 (P10; n=5) and 15 days of persistence (P15; n=5). Ovaries were obtained by bilateral ovariectomy to finally extract follicular fluid (FF) and ovarian histo-logical sections. A lower expression of ACC and PPARγ was ob-served in theca cells of P15 compared to C (p<0.05). While HMGS expression was lower in the granulosa cells of P10 compared to C, P0 and P5 (p<0.05), in theca cells, its expression was lower in the P10 compared to C (p<0.05). In theca cells, the HMGR expression was lower in all the persistence groups compared to C (p<0.05). Also, the SCOT expression was lower in the granulosa cells of P5, P10 and P15 compared to C (p<0.05). In FF, the concentrations of BHB, CHOL (total, HDL and LDL), TG and NEFA were similar in all the groups (p>0.05). These results suggest a local alteration of the enzymes related to the lipids and ketone body metabolism in the ini-tial stages of persistence, without evidencing significant changes in their related metabolites in FF. Probably, another extraovarian origin contributes to the ovarian microenvironment.