Research progress on the mechanisms underlying poultry immune regulation by plant polysaccharides.

With the rapid development of poultry industry and the highly intensive production management, there are an increasing number of stress factors in poultry production. Excessive stress will affect their growth and development, immune function, and induce immunosuppression, susceptibility to a variety of diseases, and even death. In recent years, increasing interest has focused on natural components extracted from plants, among which plant polysaccharides have been highlighted because of their various biological activities. Plant polysaccharides are natural immunomodulators that can promote the growth of immune organs, activate immune cells and the complement system, and release cytokines. As a green feed additive, plant polysaccharides can not only relieve stress and enhance the immunity and disease resistance of poultry, but also regulate the balance of intestinal microorganisms and effectively alleviate all kinds of stress faced by poultry. This paper reviews the immunomodulatory effects and molecular mechanisms of different plant polysaccharides (Atractylodes macrocephala Koidz polysaccharide, Astragalus polysaccharides, Taishan Pinus massoniana pollen polysaccharide, and alfalfa polysaccharide) in poultry. Current research results reveal that plant polysaccharides have potential uses as therapeutic agents for poultry immune abnormalities and related diseases.

[Progress on signal pathways related to bone metabolism in animals].

Bone is a hard organ that makes up vertebrate endoskeleton, which plays a role in movement, support and protection for the body. The normal growth and development of bone is in the dynamic balance of bone metabolism, which is composed of bone formation and bone absorption. This balance is very important for maintaining bone mass and mineral homeostasis. In the process of bone growth and metabolism, there are many signaling pathways regulating bone formation and absorption, such as BMP (bone morphogenetic protein)/SMADs, TGF-ß (transforming growth factor ß), Wnt/ß-catenin, OPG (osteoprotegerin)/RANKL (receptor activator of NF-κB ligand)/RANK (receptor activator of NF-κB), FGF (fibroblast growth factor) and Notch signaling pathway. These signaling pathways have complex regulatory mechanisms and are involved in the regulation of bone metabolism. In this review, we summarize the mechanism and research progress of signal pathways that play key regulatory roles in the process of animal bone metabolism, thereby laying a foundation for research in animal bone metabolism.

Metabolomics technology and its applications in agricultural animal and plant research.

Metabolomics is a discipline that uses Chromatography-Mass Spectrometry and Nuclear Magnetic Resonance techniques to identify and quantify all small molecule metabolites in living organisms and biological samples, which relies on sensitive, stable analytical procedures and improving databases. Metabolomics has been widely used in medicine, food science, crop and farm animal research, and other fields. Metabolomics can establish a more direct relationship between changes in the type and content of metabolites and phenotypes. Metabolomics has gradually become a new research method for the analysis of genetic mechanisms of complex traits following genomics, transcriptomics, and proteomics with the advances in omics technology. In this review, we firstly introduce common analytical strategies, metabolomics platforms, and metabolomics databases. Then, we review the application of metabolomics in metabolic molecular identification of important economic traits in agricultural animals, disease diagnosis, meat quality and safety detection of animal products. We also introduce the latest achievements in the development, formation and analysis of important traits of animals and plants by using metabolomics, transcriptome, and genomics. Overall, the integrated analysis of metabolomics and other omics can comprehensively explain the genetic mechanism of all kinds of complex traits and help to improve the complete biological process of "mutation-gene-expression-metabolism-phenotype". Metabolomics provides a new method for the mechanism analysis of complex characters and a novel idea for new agricultural breeding.

Effects of aqueous extracts of raw pu-erh tea and ripened pu-erh tea on proliferation and differentiation of 3T3-L1 preadipocytes.

Pu-erh tea has shown anti-obesity effects but little is known about its effect on proliferation and differentiation of preadipocytes. This study investigated the effects of the aqueous extracts of raw pu-erh tea and ripened pu-erh tea on proliferation and differentiation of murine 3T3-L1 preadiopocytes. We examined dose and time effects of both aqueous extracts on proliferation of 3T3-L1 preadipocytes. The contents of triglycerides in cytoplasm and the mRNA expression of critical transcriptional factors involved in differentiation were determined. Cytotoxicity and apoptosis rate of preadipocytes by pu-erh tea extracts treatment were test for toxic and pro-apoptotic effects. Both aqueous extracts of pu-erh tea inhibited the proliferation of 3T3-L1 preadipocytes at the selected time points. At lower concentration of raw pu-erh tea extracts (less than 300 µg/ml) and ripened pu-erh tea extracts (less than 350 µg/ml), no significant cytotoxic and pro-apoptotic were observed. Ripened pu-erh tea was more effective with lower IC50 than raw pu-erh tea. Both extracts suppressed the differentiation and down-regulated the gene expression of peroxisome proliferator-activated receptor-γ and CCAAT/enhancer binding proteins-α. Therefore, these results indicate that both aqueous extracts of pu-erh tea can inhibit proliferation and differentiation with ripened pu-erh tea more potent. Polyphenol rich in both extracts may play a role in the inhibition of proliferation and differentiation of 3T3-L1 preadipocytes.

Effect of pu-erh tea on body fat and lipid profiles in rats with diet-induced obesity.

The antiobesity and antihyperlipidaemic effects of pu-erh tea in rats with high fat diet (HFD)-induced obesity were investigated. Male Sprague-Dawley rats were randomly divided into five groups and fed varying diets for an 8-week period: control diet, HFD, and HFD supplemented with low, moderate or high doses of pu-erh tea extract (0.5 g, 2 g and 4 g/kg BW/day, respectively). Pu-erh tea significantly reduced the total body weight and the weight of various adipose pads. Pu-erh tea administration also significantly lowered plasma total cholesterol, triglyceride concentrations and low-density lipoprotein-cholesterol levels in rats with HFD-induced obesity, but did not affect high-density lipoprotein-cholesterol levels. Moreover, pu-erh tea significantly increased lipoprotein lipase, hepatic lipase and hormone-sensitive lipase activities in epididymal fat tissue in rats with HFD-induced obesity. Analysis of real-time reverse transcription-polymerase chain reaction results indicated that pu-erh tea significantly enhanced mRNA levels of hormone-sensitive lipase in rats with HFD-induced obesity. These results suggest that pu-erh tea attenuated visceral fat accumulation and improved hyperlipidemia in a rat model of HFD-induced obesity.

The polymorphisms of UCP1 genes associated with fat metabolism, obesity and diabetes.

Uncoupling protein 1 (UCP1), a 32-kDa protein located in the inner mitochondrial membrane, is abundant in brown adipose tissue, as a proton transporter in mitochondria inner membrane which uncouples oxidative metabolism from ATP synthesis and dissipates energy through the heat. UCP1 has been reported to play important roles for energy homeostasis in rodents and neonate of larger mammals including human. Recently, numerous candidate genes were searched to determine the genetic factors implicated in the pathogenesis of obesity, related metabolic disorders and diabetes. UCP-1, which plays a major role in thermogenesis, was suggested to be one of the candidates. This review summarizes data supporting the existence of brown adipocytes and the role of UCP1 in energy dissipation in adult humans, and the genetic variety association with the fat metabolism, obesity and diabetes.