# Mechanism of GBE Combined with TP on the Effect of AMPK/SREBP-1C/ACC Pathway on Lipid Metabolism in Heat-Stressed Broiler Liver

## TL;DR

This study shows that combining Ginkgo biloba extract and tea polyphenols can reduce heat stress effects on broiler liver lipid metabolism.

## Contribution

The study identifies GBE600 as an effective dosage for mitigating heat stress-induced hepatic lipid metabolism imbalance in broilers.

## Key findings

- GBE600 improved growth performance and lipid metabolism in heat-stressed broilers.
- GBE600 reduced serum TG, TC, and LDL-C levels while increasing HDL-C.
- GBE600 suppressed AMPK/SREBP-1C/ACC pathway gene expression in broiler livers.

## Abstract

Prolonged heat stress can damage the hepatic lipid metabolism system of broiler chickens, leading to increased hepatic lipid deposition. This ultimately leads to metabolic flocculation, decreased growth performance, and an effect on broiler chickens’ growth and development. Therefore, it is of great significance to investigate the inhibitory effect of HS on the abnormalities of hepatic lipid metabolism and to reduce the damage caused by HS. In this experiment, Ginkgo biloba extract (GBE) was combined with tea polyphenols, and the optimal dosage of GBE in the combination was investigated to improve the HS induced imbalance of hepatic lipid metabolism and to promote the healthy growth of broilers.

The liver accounts for almost 95% of lipid metabolism in broilers and serves as a crucial metabolic organ. Stress, which occurs when broilers are exposed to a heated environment, inhibits liver metabolism, significantly impacting their growth. This experiment investigated the combination of GBE with TP to improve hepatic lipid metabolism in heat-stressed broiler chickens by inhibiting the AMPK/SREBP-1C/ACC pathway. Three hundred broilers were reared usually until 21 days and randomly divided into six groups, namely CON group, HS group, TP group (300 mg/kg), GBE100 group (GBE100 mg/kg + TP300 mg/kg), GBE300 group (GBE 300 mg/kg + TP 300 mg/kg), GBE600 (600 mg/kg + TP 300 mg/kg) groups, where the CON group was kept at 23 °C, and the HS group and the TP, GBE100, GBE300, and GBE600 groups of each medication group were kept at 35 ± 2 °C for 10 h per day. Liver and serum samples were extracted at 28 and 42 days of age, respectively. The results showed that, at 42 days of age, the GBE600 group exhibited significantly superior performance to the HS group in ADG, ADFI, and F/G (p < 0.01). Serum TG, TC, and LDL-C levels were significantly lower (p < 0.01), while HDL-C levels were significantly higher (p < 0.05). Additionally, the mRNA expression levels of LKB1, AMPK, SREBP-1C, and ACC were markedly reduced (p < 0.01). In contrast, the mRNA expression of HSL and CPT1A was significantly elevated (p < 0.01), indicating that the GBE600 was more effective in mitigating heat stress in broiler chickens at 42 days of age. It showed that the GBE600 was more effective in ameliorating heat stress in broilers at 42 days of age, thus providing an ethical basis for ameliorating the flocculation of hepatic lipid metabolism in heat-stressed broilers.