Qiongxian Yan

L-Theanine Improves Immunity by Altering TH2/TH1 Cytokine Balance, Brain Neurotransmitters, and Expression of Phospholipase C in Rat Hearts

Background This study aimed to investigate the regulatory effects of L-theanine on secretion of immune cytokines, hormones, and neurotransmitters, and mRNA expression of phospholipase C (PLC) in rats, and to explore its regulatory mechanism in immune function. Material/Methods Sixty-four Sprague-Dawley rats received daily intragastric infusion of different doses of L-theanine solution [0, 50 (LT), 200 (MT), and 400 (HT) mg/kg BW]. Cytokines, immunoglobulins, and hormones in the serum, neurotransmitters, and mRNA expression of PLC in the relevant tissues were assayed. Results L-theanine administration increased the splenic organ index and decreased the contents of ILs-4/6/10 and the ratio of IL-4/IFN-γ in the serum. High-dose L-theanine administration increased the levels of dopamine and 5-hydroxytryptamine in the pituitary and hippocampus, resulting in decrease in corticosterone level in the serum. L-theanine administration decreased the mRNA expressions of PLC isomers in the liver and PLC-γ1 and PLC-δ1 in the spleen. Interestingly, mRNA expressions of PLC-βf1 in the spleen and PLC isomers mRNA in the heart were up-regulated by L-theanine administration. Conclusions Administration of 400 mg/kg BWL-theanine improved immune function of the rats by increasing the splenic weight, altering the Th2/Th1 cytokine balance, decreasing the corticosterone level in the serum, elevating dopamine and 5-hydroxytryptamine in the brain, and regulating the mRNA expression of PLC isomers in the heart.

Effects of energy and protein restriction, followed by nutritional recovery on morphological development of the gastrointestinal tract of weaned kids.

Effects of energy, protein, or both energy and protein restriction on gastrointestinal morphological development were investigated in 60 Liuyang Black kids, which were sourced from local farms and weaned at 28 d of age. Weaned kids were randomly assigned to receive 1 of 4 dietary treatments (15 kids per treatment), which consisted of adequate nutrient supply (CON), energy restriction (ER), protein restriction (PR), or energy and protein restriction (EPR). The entire experiment included adaptation period (0 to 6 d), nutritional restriction period (7 to 48 d), and recovery period (49 to 111 d). Three kids from each group were killed at d 48 and 111, and the rumen, duodenum, jejunum, and ileum were harvested. On d 48 (end of nutritional restriction), lengths of the duodenum (P = 0.005), jejunum (P = 0.003), and ileum (P = 0.003), and weights of the rumen (P = 0.004), duodenum (P = 0.006), jejunum (P = 0.006), and ileum (P = 0.004) of kids in ER, PR, and EPR were less than those of kids in CON. Compared with CON, PR decreased papillae width (P = 0.03) and surface area (P = 0.05) of the rumen epithelium, villus surface area (P = 0.05), and N concentration (P = 0.02) of the jejunum mucosa on d 48. Compared with CON, EPR decreased papillae height (P = 0.001), width (P = 0.001), and surface area (P = 0.003), N concentration (P = 0.01), and the ratio of N to DNA (P = 0.03) of the rumen epithelium. Compared with CON, EPR also decreased villus height (P = 0.01), width (P = 0.006), and surface area (P = 0.006), N concentration (P < 0.001), and the ratio of N to DNA (P < 0.001) of the jejunum mucosa on d 48. On d 111 (end of nutritional recovery), lengths of the duodenum (P = 0.001), jejunum (P = 0.001), and ileum (P = 0.001), weights of the rumen (P < 0.001), duodenum (P = 0.001), jejunum (P < 0.001), and ileum (P < 0.001) of kids in ER, PR, and EPR were still less than those of kids in CON; N concentrations of rumen epithelium of kids in PR (P = 0.01) and EPR (P = 0.001), and the ratio of N to DNA of jejunum mucosa of kids in EPR (P < 0.001) were greater than those of kids in CON. Results indicate that nutritional restriction of 6 wk can retard gastrointestinal morphological development for kids weaned at 28 d of age and retarded development remains evident, even after nutritional recovery of 9 wk.

Cloning, Phylogenetic Analysis, and Distribution of Free Fatty Acid Receptor GPR120 Expression along the Gastrointestinal Tract of Housing versus Grazing Kid Goats

G-protein-coupled receptor 120 (GPR120) is reported as a long-chain fatty acid (LCFA) receptor that elicits free fatty acid (FFA) regulation on metabolism homeostasis. The study aimed to clone the gpr120 gene of goats (g-GPR120) and subsequently investigate phylogenetic analysis and tissue distribution throughout the digestive tracts of kid goats, as well as the effect of housing versus grazing (H vs G) feeding systems on GPR120 expression. Partial coding sequence (CDS) of g-GPR120 was cloned and submitted to NCBI (accession no. KU161270 ). Phylogenetic analysis revealed that g-GPR120 shared higher homology in both mRNA and amino acid sequences for ruminants than nonruminants. Immunochemistry, real-time PCR, and Western blot analysis showed that g-GPR120 was expressed throughout the digestive tracts of goats. The expression of g-GPR120 was affected by feeding system and age, with greater expression of g-GPR120 in the G group. It was concluded that the g-GPR120-mediated LCFA chemosensing mechanism is widely present in the tongue and gastrointestinal tract of goats and that its expression can be affected by feeding system and age.

Proteomic Analysis of Isolated Plasma Membrane Fractions from the Mammary Gland in Lactating Cows

The mammary gland of dairy cows is a formidable lipid-synthesizing machine for lactation. This unique function depends on the activities of plasma membrane (PM) proteins in mammary cells. Little information is known about the expression profiles of PM proteins and their functions during the lactating process. This study investigated the proteome map of PM fractions of mammary gland in lactating cows using 1D-Gel-LC-MS/MS and identified 872 nonredundant proteins with 141 unknown proteins, wherein 215 were PM-associated proteins. Most of the PM-associated proteins were binding, transport, and catalytic proteins such as annexin proteins, heat shock proteins, integrins, RAS oncogene family members, and S100 calcium binding proteins. The PM-associated pathways such as caveolae-mediated endocytosis, leukocyte extravasation, aldosterone signaling in epithelial cells, and remodeling of epithelial adherens junctions were also significantly over-represented. Proteomic analysis revealed the characteristics and predicted functions of PM proteins isolated from the lactating bovine mammary gland. These results further provide experimental evidence for the presence of many proteins predicted in the annotated bovine genome. The data generated here also provide a reference for the PM-related functional research in the mammary gland of lactating cows.

Effects of Momordica charantia polysaccharide on in vitro ruminal fermentation and cellulolytic bacteria

Abstract Four levels of Momordica charantia polysaccharide (MCP) supplements (0, 0.1, 0.3, 0.6 mg/ml) were designed to investigate the effects of MCP on ruminal fermentation and cellulolytic bacteria in vitro. The pH, ammonia-N (NH3-N) and volatile fatty acids (VFA) were measured at 6, 24, 48 h, whilst the cellulolytic bacteria population was determined at 6 and 24 h. The 0.6 mg/ml MCP inclusion decreased the theoretical maximum of gas production and the half-life. The NH3-N concentration was decreased by MCP at all doses at 24 h. The MCP inclusion increased the concentration of total VFA at 24 and 48 h and the acetate to propionate ratio, the molar proportion of isovalerate at 6 h, while decreased that of isobutyrate at 24 h and that of isovalerate, valerate at 24 and 48 h, respectively. The relative abundances of Ruminococcus albus and Ruminococcus flavefaciens were decreased at 6 h, while that of Butyrivibrio fibrisolvens was increased at all times of incubation and that of Fibrobacter succinogenes reached the greatest value at 0.6 mg/ml MCP supplementation at 24 h. This study demonstrated that the MCP had the ability to enhance the total VFA production, modulate the rumen fermentation pathway and influence the number of cellulolytic bacteria population.

Effects of Momordica charantia Saponins on In vitro Ruminal Fermentation and Microbial Population

This study was conducted to investigate the effects of Momordica charantia saponin (MCS) on ruminal fermentation of maize stover and abundance of selected microbial populations in vitro. Five levels of MCS supplements (0, 0.01, 0.06, 0.30, 0.60 mg/mL) were tested. The pH, NH3-N, and volatile fatty acid were measured at 6, 24, 48 h of in vitro mixed incubation fluids, whilst the selected microbial populations were determined at 6 and 24 h. The high dose of MCS increased the initial fractional rate of degradation at t-value = 0 (FRD0) and the fractional rate of gas production (k), but decreased the theoretical maximum of gas production (VF) and the half-life (t0.5) compared with the control. The NH3-N concentration reached the lowest concentration with 0.01 mg MCS/mL at 6 h. The MSC inclusion increased (p<0.001) the molar proportion of butyrate, isovalerate at 24 h and 48 h, and the molar proportion of acetate at 24 h, but then decreased (p<0.05) them at 48 h. The molar proportion of valerate was increased (p<0.05) at 24 h. The acetate to propionate ratio (A/P; linear, p<0.01) was increased at 24 h, but reached the least value at the level of 0.30 mg/mL MCS. The MCS inclusion decreased (p<0.05) the molar proportion of propionate at 24 h and then increased it at 48 h. The concentration of total volatile fatty acid was decreased (p<0.001) at 24 h, but reached the greatest concentration at the level of 0.01 mg/mL and the least concentration at the level of 0.60 mg/mL. The relative abundance of Ruminococcus albus was increased at 6 h and 24 h, and the relative abundance of Fibrobacter succinogenes was the lowest (p<0.05) at 0.60 mg/mL at 6 h and 24 h. The relative abundance of Butyrivibrio fibrisolvens and fungus reached the greatest value (p<0.05) at low doses of MCS inclusion and the least value (p<0.05) at 0.60 mg/mL at 24 h. The present results demonstrates that a high level of MCS quickly inhibits in vitro fermentation of maize stover, while MCS at low doses has the ability to modulate the ruminal fermentation pattern by regulating the number of functional rumen microbes including cellulolytic bacteria and fungi populations, and may have potential as a feed additive applied in the diets of ruminants.

L-Theanine Administration Modulates the Absorption of Dietary Nutrients and Expression of Transporters and Receptors in the Intestinal Mucosa of Rats

L-theanine has various advantageous functions for human health; whether or not it could mediate the nutrients absorption is unknown yet. The effects of L-theanine on intestinal nutrients absorption were investigated using rats ingesting L-theanine solution (0, 50, 200, and 400 mg/kg body weight) per day for two weeks. The decline of insulin secretion and glucose concentration in the serum was observed by L-theanine. Urea and high-density lipoprotein were also reduced by 50 mg/kg L-theanine. Jejunal and ileac basic amino acids transporters SLC7a1 and SLC7a9, neutral SLC1a5 and SLC16a10, and acidic SLC1a1 expression were upregulated. The expression of intestinal SGLT3 and GLUT5 responsible for carbohydrates uptake and GPR120 and FABP2 associated with fatty acids transport were inhibited. These results indicated that L-theanine could inhibit the glucose uptake by downregulating the related gene expression in the small intestine of rats. Intestinal gene expression of transporters responding to amino acids absorption was stimulated by L-theanine administration.

Alteration of Mevalonate Pathway in Rat Splenic Lymphocytes: Possible Role in Cytokines Secretion Regulated by L-Theanine

L-Theanine is a nonprotein amino acid in tea, and its immunomodulatory function has been confirmed. This study aimed to investigate the effect of L-theanine addition on cytokines secretion in rat splenic lymphocytes and explore its potential immunomodulatory effects on the mevalonate biosynthetic pathway. Our results showed that L-theanine treatment did not influence the proliferation and division indexes of the splenic lymphocytes subsets. Interestingly, L-theanine treatment had regulated the contents of IFN-γ, IL-2, IL-4, IL-10, IL-12, and TNF-α  (P < 0.001) except IL-6 and upregulated the mRNA and protein expression of Ras-related protein Rap-1A (Rap1A), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), and farnesyl diphosphate synthase (FDPs) (P < 0.001). Additionally, there was a positive correlation between Rap1A and HMGCR proteins expression and IFN-γ, IL-4, and IL-6 levels. In conclusion, L-theanine regulated the secretion of cytokines probably by activating expression of Rap1A and HMGCR proteins involved in the mevalonate biosynthetic pathway in rat splenic lymphocytes. Therefore, L-theanine might be a promising potential drug candidate as immunopotentiator.

Effects of maternal feed intake restriction during pregnancy on the expression of growth regulation, imprinting and epigenetic transcription-related genes in foetal goats

Maternal nutrition during gestation is a leading factor of modifying the foetal epigenome and phenotype for mammals. Imprinting genes have important roles in regulating foetal growth, programming and development. There, however, are limited data available on the effects of feed intake restriction on the expression of imprinting genes in pregnant goats. The present study, therefore, was conducted to assess the effects of maternal feed intake restriction on the relative abundance of mRNA for growth imprinting, DNA methyltransferase (DNMT) and epigenetic transcription-related genes in the liver and heart of foetal goats during gestation. A total of 24 Liuyang black goats (2.0±0.3 yr) with similar body weight (BW, 31.22±8.09 kg) and parity (2) were allocated equally to either a control group (CG) or a restriction group (RG) during both early (from 26 to 65 days) and late (from 96 to 135 days) gestation. All goats were fed a mixed diet and had free access to fresh water. The feed of the RG was 40% less than that of the CG. The early and late gestation goats were weighed, bled and slaughtered on days 65 and 135 of gestation, respectively. In early gestation, the foetal weight, body length, the weight of foetal heart and liver were greater (P <  0.05) in the RG. The CpG methylation of genomic DNA in the foetal heart was less (P =  0.0001) in the RG. The relative abundance of mRNA of methyl-CpG-binding domain protein 2 (MBD2) and methyl-CpG-binding domain protein 3 (MBD3) genes in the foetal liver were greater (P <  0.05) in the RG. During the late gestation, the foetal weight, heart weight and liver weight were less (P <  0.05) in the RG. The relative abundance of mRNA for the MBD2 gene (P =  0.043) in the foetal heart, and the ten-eleven translocation protein 1 (TET1) gene (P <  0.05) in both the foetal heart and liver were greater in the RG. These results indicate feed intake restriction during gestation influenced foetal development and regulated the relative abundance of mRNA for epigenetic transcription-related genes.

Replacement of oat grass with highland barley straw: effects on lipid profiles, FA composition and lipogenetic genes expression in Tibetan sheep

Abstract Studies associated with regional roughage utilisation in Tibetan sheep have been limited. This study focussed on the mechanism of lipid metabolism and deposition in Tibetan sheep fed local roughage sources. Twenty-four Tibetan sheep weighing 16.1 ± 1.76 kg were randomly assigned to two mixed diets containing the same concentrate mixed with oat grass (OG) or highland barley straw (HBS). The ME and CP of OG diet were 7.16 MJ/kg DM and 5.94%, respectively, while in HBS diet were 7.13 MJ/kg DM and 7.39%. Lipid profiles in the plasma and liver, fatty acid (FA) composition and lipogenetic genes expression in the muscle and adipose tissue were determined. No difference was observed in DMI, total cholesterol, triglyceride, low-density lipoprotein and high-density lipoprotein levels in the plasma and liver of sheep between two groups (p>.05). Plasma leptin and liver non-esterified fatty acid (NEFA) content in HBS group tended to be greater than that in OG group (p < .01). Sheep in HBS group had greater C18:2, C20:4, PUFA and PUFA/SFA ratio in the longissimus dorsi muscle (p < .05) and lower C17:0 (p = .05) and C20:1 (p < .01) in the perirenal adipose fat. Perirenal C18:0, C20:3 and C20:4 contents in HBS group tended to increase (p < .01). HBS stimulated the mRNA expression of SCD, C/EBPγ and SREBF1 in the muscle and FASN in the perirenal adipose fat (p < .01), but inhibited HSL, LPL, C/EBPγ and PPARγ expression in the perirenal adipose fat. These results indicated that replacement of OG by HBS promotes PUFA deposition in the muscle and long-chain FAs in the adipose fat of Tibetan sheep. Lipid deposition-related genes (SCD, FASN, HSL and LPL) and lipid metabolism regulators (C/EBPγ, SREBF1 and PPARγ) are involved in the transcriptional regulation.