Research Sharing || Impact of Eucommia ulmoides Leaves on Hepatic Glucose Metabolism and Gene Expression in Sheep

Professor Gao Yan's team at Henan Agricultural University is deeply involved in the field of ruminant nutritional regulation. They are a pivotal force in domestic sheep nutritional metabolism research, particularly in the application of natural plant resources in sheep farming. Focusing on key technologies for regulating sheep glucose metabolism, with "green farming, quality improvement, and efficiency enhancement" as their core direction, the team's research provides important theoretical support for healthy sheep farming and precision nutritional regulation.

01 Experimental Design

Led by Professor Gao Yan's team, this trial aimed to explore the effects of Eucommia ulmoides leaves (EUL) on liver glucose metabolism and related gene expression in sheep, providing a scientific basis for the rational application of EUL in sheep farming. Twelve Dorper × Hu crossbred sheep (6–8 months old, weighing 35–40 kg) were selected and randomly divided into two groups of six: the control group (CTL group) and the EUL group (diet supplemented with 10% EUL). With a 10-day pre-trial period and a 30-day formal trial period, the experimental design was rigorous, with all feeding variables controlled to ensure precise and reliable data.

02 Experimental Results

By collecting blood and liver tissues, the trial systematically detected glucose metabolism indicators, transcriptomic characteristics, and gene/protein expression levels. The results showed that EUL has a significant regulatory effect on sheep glucose metabolism: compared to the CTL group, the plasma glucose (GLU) and serum glucagon (GC) content in the EUL group were significantly decreased (P < 0.05), while serum insulin (INS) content was significantly increased (P < 0.05), effectively regulating the body's glucose homeostasis.

• Transcriptomic detection indicated:

The differentially expressed genes between the two groups were closely related to glucose and energy metabolism, with significant enrichment in glucose metabolism-related pathways. Fluorescence quantitative PCR (RT-qPCR) results showed that in the EUL group, the mRNA expression levels of liver INSR and IRS2 were highly significantly increased (P < 0.01), while GCGR mRNA expression was highly significantly decreased (P < 0.01). Additionally, the mRNA of the key glycolytic enzyme PFKL was significantly up-regulated (P<0.05); the gluconeogenesis-related enzymes G6Pase mRNA (P<0.01) and PEPCK1 mRNA (P<0.05) were significantly down-regulated. FoxO1 and CREB mRNA were highly significantly down-regulated (P < 0.01), while the key hepatic glycogen synthesis enzyme Gys2 mRNA was highly significantly up-regulated (P < 0.01).

• Western blot results showed:

In the EUL group, there was no significant change in INSR protein expression (P > 0.05), while the protein expressions of FoxO1, G6Pase, and PEPCK1 were highly significantly down-regulated (P < 0.01).

03 Conclusion

In summary, the research by Professor Gao Yan's team clarified that dietary supplementation with 10% EUL can promote glycolysis and hepatic glycogen synthesis while inhibiting gluconeogenesis by regulating relevant genes and protein expressions in sheep, thereby lowering blood glucose. This study fills the gap in the application of Eucommia ulmoides leaves in the regulation of sheep glucose metabolism, enriches the theory of ruminant nutritional regulation, and provides technical support for the promotion and application of natural plant resources in sheep farming, highlighting the research strength of Professor Gao Yan's team in the field of sheep nutrition.

Special Note: This article is intended for the objective review of research progress and academic discussion. The content is derived from published scientific research literature and is not intended as product promotion or usage recommendations.

Reference

Gao Yan, Yang Gaiqing, Wang Linfeng, et al. Effects of Eucommia ulmoides leaves on liver glucose metabolism and related gene expression in sheep [J]. Chinese Journal of Animal Nutrition. 2019, (6). DOI: 10.3969/j.issn.1006-267x.2019.06.046.