The Improved Milk Quality and Enhanced Anti-Inflammatory Effect in Acetylserotonin-O-methyltransferase (ASMT) Overexpressed Goats: An Association with the Elevated Endogenous Melatonin Production.

Hao Wu,Yujun Yao,Xiaosheng Zhang,Tuan Yu,Guangdong Li,Zhengxing Lian,Jinlong Zhang,Xudai Cui,Shengyu Guan,Lu Zhang,Guoshi Liu,Yunxiang Li,Haixin Wu

doi:10.3390/molecules27020572

Abstract

Background: Transgenic animal production is an important means of livestock breeding and can be used to model pharmaceutical applications. Methods: In this study, to explore the biological activity of endogenously produced melatonin, Acetylserotonin-O-methyltransferase (ASMT)-overexpressed melatonin-enriched dairy goats were successfully generated through the use of pBC1-ASMT expression vector construction and prokaryotic embryo microinjection. Results: These transgenic goats have the same normal phenotype as the wild-type goats (WT). However, the melatonin levels in their blood and milk were significantly increased (p < 0.05). In addition, the quality of their milk was also improved, showing elevated protein content and a reduced somatic cell number compared to the WT goats. No significant changes were detected in the intestinal microbiota patterns between groups. When the animals were challenged by the intravenous injection of E. coli, the ASMT-overexpressed goats had a lower level of pro-inflammatory cytokines and higher anti-inflammatory cytokines compared to the WT goats. Metabolic analysis uncovered a unique arachidonic acid metabolism pattern in transgenic goats. Conclusions: The increased melatonin production due to ASMT overexpression in the transgenic goats may have contributed to their improved milk quality and enhanced the anti-inflammatory ability compared to the WT goats.

Highlights

IntroductionMelatonin affects immune system function and the nervous system through endocrine effects
We explored the effects of ASMT overexpression on the milk quality and fatty acid metabolism in the anti-inflammatory response of transgenic animals compared to wild-type goats (WT) animals
The Coding DNA Sequence (CDS) region of the ASMT gene was cloned from the pineal gland of a goat for the construction of mammary gland-specific expression vector pBC1ASMT (Figure 1B)

Summary

Introduction

Melatonin affects immune system function and the nervous system through endocrine effects. The therapeutical effects of melatonin have been tested in many disease-associated models, including neurodegenerative diseases. Melatonin treatment effectively retards the processes of Alzheimer’s disease [7], multiple sclerosis [8], and amyotrophic lateral sclerosis [9]. Melatonin is regularly used to treat primary sleep disorders and sleep disorders related to neuronal diseases in children [10,11]. All the disorders mentioned above are more or less associated with imbalanced immunity and inflammation [12]. Inflammation is a complex pathophysiological process, and the dynamic balance of pro-inflammatory and anti-inflammatory mediators in the body maintains inflammatory homeostasis [13]

Methods

Results

Discussion

Conclusion