Dietary amylose:amylopectin ratio influences the expression of amino acid transporters and enzyme activities for amino acid metabolism in the gastrointestinal tract of goats.

This study was designed to investigate the effects of dietary starch structure on muscle protein synthesis and gastrointestinal amino acid (AA) transport and metabolism of goats. Twenty-seven Xiangdong black female goats (average body weight = 9·00 ± 1·12 kg) were randomly assigned to three treatments, i.e., fed a T1 (normal maize 100 %, high amylose maize 0 %), T2 (normal maize 50 %, high amylose maize 50 %) and T3 (normal maize 0 %, high amylose maize 100 %) diet for 35 d. All AA in the ileal mucosa were decreased linearly as amylose:amylopectin increased in diets (P < 0·05). The plasma valine (linear, P = 0·03), leucine (linear, P = 0·04) and total AA content (linear, P = 0·03) increased linearly with the increase in the ratio of amylose in the diet. The relative mRNA levels of solute carrier family 38 member 1 (linear, P = 0·01), solute carrier family 3 member 2 (linear, P = 0·02) and solute carrier family 38 member 9 (linear, P = 0·02) in the ileum increased linearly with the increase in the ratio of amylose in the diet. With the increase in the ratio of amylose:amylopectin in the diet, the mRNA levels of acetyl-CoA dehydrogenase B (linear, P = 0·04), branched-chain amino acid transferase 1 (linear, P = 0·02) and branched-chain α-keto acid dehydrogenase complex B (linear, P = 0·01) in the ileum decreased linearly. Our results revealed that the protein abundances of phosphorylated mammalian target of rapamycin (p-mTOR) (P < 0·001), phosphorylated 4E-binding protein 1 (P < 0·001) and phosphorylated ribosomal protein S6 kinases 1 (P < 0·001) of T2 and T3 were significantly higher than that of T1. In general, a diet with a high amylose ratio could reduce the consumption of AA in the intestine, allowing more AA to enter the blood to maintain higher muscle protein synthesis through the mTOR pathway.

Chlorogenic acid inhibits forming of diabetes mellitus in rats induced by high-fat high-sucrose and streptozotocin.

To evaluate the inhibitory effect of chlorogenic acid on the forming of type 2 diabetes mellitus (T2DM), using Sprague Dawley (SD) rats, a recognized T2DM model induced by high-fat high-sucrose diet (HFSD) and streptozotocin (STZ). Thirty female SD rats were assigned equally to three groups randomly: normal control with standard commercial (NC), chlorogenic acid treatment with HFSD and chlorogenic acid (90mg/kg, CA), and diabetes model with HFSD (DM). Upon treatment with chlorogenic acid, suppression of the onset of diabetes, reduced serum glucose and insulin concentrations, improved glucose tolerance and increased body weight and visceral fat weight were observed. Serum triglyceride, total cholesterol, low density lipoprotein levels, and kidney and pancreas morphology were significantly ameliorated. Chlorogenic acid also inhibited the mRNA levels of hepatic G-6-Pase and up-regulated the mRNA levels of skeletal muscle GLUT4. Our results indicated that before the onset of diabetes, chlorogenic acid had an inhibitory effect against the forming of T2DM induced by HFSD and STZ through regulating the glucose and lipid metabolism.

Polygonatum odoratum Polysaccharides Modulate Gut Microbiota and Mitigate Experimentally Induced Obesity in Rats.

Increasing evidence suggests that the gut microbiota plays vital roles in metabolic diseases. Polygonatum odoratum extract alleviates hyperglycemia and hyperlipidemia, but the underlying mechanism remains unclear. This study investigated the effects of P. odoratum polysaccharides (POPs) on high-fat diet (HFD)-induced obesity in rats and whether these effects were related to modulation of gut microbiota. POP treatment attenuated weight gain, fat accumulation, epididymal adipocyte size, liver triglycerides, and total liver cholesterol content in HFD-fed rats. POP administration also increased short-chain fatty acids (SCFAs), including isobutyric acid, butyric acid, and valeric acid. POP upregulated the expression of genes involved in adipocyte differentiation (Pparg, Cebpa, Cebpb) and lipolysis (Ppara, Atgl), and downregulated those related to lipid synthesis (Srebpf1, Fabp4, Fas), with corresponding changes in PPARγ and FABP4 protein expression. Finally, POP enhanced species richness and improved the gut microbiota community structure, reducing the relative abundances of Clostridium, Enterococcus, Coprobacillus, Lactococcus, and Sutterella. Principal coordinates analysis (PCoA) revealed a clear separation between HFD-fed rats and all other treatment groups. Correlation analysis identified negative and positive associations between obesity phenotypes and 28 POP-influenced operational taxonomic units (OTUs), including putative SCFA-producing bacteria. Our data suggest that POP supplementation may attenuate features of obesity in HFD-fed rats in association with the modulation of gut microbiota.

Effects of Chain Length and Saturability of Fatty Acids on Phospholipids and Proteins in Plasma Membranes of Bovine Mammary Gland.

Free fatty acids (FFAs) in plasma are essential substrates for de novo synthesis of milk fat, or directly import into mammary cells. The physico-chemical properties of mammary cells membrane composition affected by FFAs with different chain lengths and saturability are unclear yet. Employing GC, FTIR and fluorescence spectroscopy, the adsorption capacity, phospholipids content, membrane proteins conformation, lipid peroxidation product, and free sulfhydryl of plasma membranes (PMs) interacted with different FFAs were determined. The mammary cells PMs at 38 and 39.5 °C showed different adsorption capacities: acetic acid (Ac) > stearic acid (SA) > ß-hydroxybutyric acid (BHBA) > trans10, cis12 CLA. In the FTIR spectrum, the major adsorption peaks appeared at 2920 and 2850 cm-1 for phospholipids, and at 1628 and 1560 cm-1 for membrane proteins. The intensities of PMs-FFAs complexes were varied with the FFAs species and their initial concentrations. The ß-sheet and turn structures of membrane proteins were transferred into random coil and α-helix after BHBA, SA and trans10, cis12 CLA treatments compared with Ac treatment. The quenching effects on the fluorescence of endogenous membrane protein, 1, 8-ANS, NBD-PE, and DHPE entrapped in PMs by LCFA were different from those of short chain FFAs. These results indicate that the adsorption of FFAs could change membrane protein conformation and polarity of head group in phospholipids. This variation of the mammary cells PMs was regulated by carbon chain length and saturability of FFAs.

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 (V F) 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.

Evaluation of Different Yeast Species for Improving In vitro Fermentation of Cereal Straws.

Information on the effects of different yeast species on ruminal fermentation is limited. This experiment was conducted in a 3×4 factorial arrangement to explore and compare the effects of addition of three different live yeast species (Candida utilis 1314, Saccharomyces cerevisiae 1355, and Candida tropicalis 1254) at four doses (0, 0.25×10(7), 0.50×10(7), and 0.75×10(7) colony-forming unit [cfu]) on in vitro gas production kinetics, fiber degradation, methane production and ruminal fermentation characteristics of maize stover, and rice straw by mixed rumen microorganisms in dairy cows. The maximum gas production (Vf), dry matter disappearance (IVDMD), neutral detergent fiber disappearance (IVNDFD), and methane production in C. utilis group were less (p<0.01) than other two live yeast supplemented groups. The inclusion of S. cerevisiae reduced (p<0.01) the concentrations of ammonia nitrogen (NH3-N), isobutyrate, and isovalerate compared to the other two yeast groups. C. tropicalis addition generally enhanced (p<0.05) IVDMD and IVNDFD. The NH3-N concentration and CH4 production were increased (p<0.05) by the addition of S. cerevisiae and C. tropicalis compared with the control. Supplementation of three yeast species decreased (p<0.05) or numerically decreased the ratio of acetate to propionate. The current results indicate that C. tropicalis is more preferred as yeast culture supplements, and its optimal dose should be 0.25×10(7) cfu/500 mg substrates in vitro.

Effects of the dietary ratio of ruminal degraded to undegraded protein and feed intake on intestinal flows of endogenous nitrogen and amino acids in goats.

This study was conducted to evaluate the effects of the dietary ratio of ruminal degraded protein (RDP) to ruminal undegraded protein (RUP) and the dry matter intake (DMI) on the intestinal flows of endogenous nitrogen (N) and amino acids (AA) in goats. The experiment was designed as a 4×4 Latin square using four ruminally, duodenally and ileally cannulated goats. The treatments were arranged in a 2×2 factorial design; two ratios of RDP to RUP (65:35 and 45:55, RDP1 and RDP2, respectively) and two levels at 95% and 75% of voluntary feed intake (DMI1 and DMI2, respectively) were fed to the goats. There were no significant differences in the N intake, duodenal flow of total N, undegraded feed N, microbial N, endogenous N or ileal flow of endogenous N, but the duodenal and ileal flow of endogenous N numerically decreased by approximately 22% and 9%, respectively, when the feed intake changed from DMI1 (0.63 kg/d) to DMI2 (0.50 kg/d). The dietary ratio of RDP to RUP had significant effects (p<0.05) on the ileal flows of endogenous leucine, phenylalanine and cysteine. The present results implied that the duodenal flows of endogenous N and AA decreased when the dietary RDP to RUP ratio and DMI decreased, and the flow of endogenous AA at the ileum also decreased when the DMI decreased but increased with decreasing RDP to RUP ratios.

Effects of dietary cellulase and xylanase addition on digestion, rumen fermentation and methane emission in growing goats.

The objective of this study was to evaluate the effectiveness of supplementation of cellulase and xylanase to diets of growing goats to improve nutrient digestibility, utilisation of energy and mitigation of enteric methane emissions. The experiment was conducted in a 5 × 5 Latin square design using five goats with permanent rumen fistulae and five treatments consisted of two levels of cellulase crossed over with two levels of xylanase plus unsupplemented Control. The cellulase (243 U/g) derived from Neocallimastix patriciarum was added at 0.8 and 1.6 g/kg dry matter intake (DMI) and the xylanase (31,457 U/ml) derived from Aspergillus oryzae was fed at 1.4 and 2.2 ml/kg DMI. There were no differences in apparent digestibility of organic matter, neutral detergent fibre, acid detergent fibre and rumen fermentation parameters (i.e. ammonia-nitrogen [N], volatile fatty acids) among all treatments. Dietary cellulase and xylanase addition did not influence energy and N utilisation. But compared to xylanase addition at the higher dose, at the low xylanase dose the retained N, the availability of retained N and digested N were increased (p < 0.01). Moreover, enzyme addition did not affect the enteric methane emission and community diversity of ruminal methanogens. The present results indicated that previous in vitro findings were not confirmed in ruminant trials.

In vitro evaluation on neutral detergent fiber and cellulose digestion by post-ruminal microorganisms in goats.

BACKGROUND: Post-ruminal digestion of fiber has received much less attention than its ruminal digestion. Using in vitro incubation techniques, the present study explored whether variations in fiber digestion occurred in different segments of the post-ruminal tract and whether fiber structure could influence its digestibility. A split plot design was conducted with gut segments (jejunum, ileum, cecum and colon) as main plot and substrates (neutral detergent fiber (NDF) and cellulose (CEL)) as subplot. RESULTS: With the same substrate, the final asymptotic gas volume (V(F)), gas production at t(i) (V(t(i)), digestibility, microbial crude protein (MCP), total bacteria number (TBN), total short-chain fatty acids (TSCFA) and xylanase in incocula from the cecum and colon exceeded (P < 0.01) those in incocula from the jejunum and ileum, while the NH3-N in the former was less (P < 0.01). For the same gut segment, the digestion of CEL was superior to NDF, as reflected in greater V(F), V(t(i)), maximum rate of gas production, digestibility, enzyme activities and SCFA but lower pH and NH3-N. CONCLUSION: The current results imply that the intestinal contents from the cecum and colon have greater potential to digest fiber than those from the jejunum and ileum, and CEL is more easily digested in the post-ruminal tract than NDF.

Replacing ZnSO4 with Zn-glycine in the diet of goat promotes the pancreatic function of the offspring.

Zinc supplementation in the diet of goats affects pancreas development in offspring. However, the impact of maternal inorganic and organic zinc supplementation in offspring is poorly defined. In this study, 14 late-pregnant goats were assigned at random to the zinc sulfate group (ZnSO4, n = 7) and the zinc-glycine chelate group (Zn-Gly, n = 7), respectively. Serum samples and pancreas tissue were collected from kids whose mothers were fed ZnSO4 and Zn-Gly at the late pregnancy, respectively. Histologic examination showed no morphologic differences between the 2 groups. Pancreatic zinc content in kids tended to be increased when replacing ZnSO4 with Zn-Gly. The serum insulin concentration was greater and glucagon less in the Zn-Gly group when compared to the ZnSO4 group. The activities of lipase and chymotrypsin were enhanced when replacing ZnSO4 with Zn-Gly. Proteomics results showed that 234 proteins were differentially expressed between the 2 groups, some of which were associated with the secretion of insulin, enzyme activity and signal transduction. The results suggested that supply of dietary Zn-Gly to goats during late pregnancy promoted pancreatic function in offspring compared with dietary ZnSO4 supplementation. This provides new information about pancreatic function when supplementing different zinc sources in the diets of late pregnant goats.

Rumen-protected glucose stimulates the secretion of reproductive hormones and the mTOR/AKT signaling pathway in the ovaries of early postpartum.

This study was conducted to determine the response of the reproductive hormones and the mTOR/AKT/PI3K pathway in the ovaries of postpartum dairy cows with dietary rumen-protected glucose (RPG). Twelve Holstein cows were randomly assigned to two groups (n = 6/group): the control group (CT) and the RPG group. Blood samples were collected on d 1, 7, and 14 after calving for the gonadal hormone assay. The expression of the gonadal hormones receptors and PI3K/mTOR/AKT pathways were detected using RT-PCR and Western blot. The RPG addition increased the plasma LH, E2, and P4 concentrations on d 14 after calving and upregulated the mRNA and protein expressions of the ERα, ERß, 17ß-HSD, FSHR, LHR, and CYP17A1 but downregulated StAR expression. Immunohistochemical analysis identified higher expressions of the FSHR and LHR in the ovaries of RPG-fed cows compared to CT cows. Furthermore, the protein expressions of p-AKT/AKT and p-mTOR/mTOR were significantly increased in the ovaries of RPG-fed cows compared to the CT group, but the addition of RPG did not alter the protein expression of p-PI3K/PI3K. In conclusion, the current results indicated that dietary RPG supplementation regulated gonadotropin secretion and stimulated expression of hormone receptors and the mTOR/AKT pathway in the ovaries of early postpartum dairy cows. RPG may be beneficial for the recovery of ovarian activity in post-calving dairy cows.

Application of different proportions of sweet sorghum silage as a substitute for corn silage in dairy cows.

This experiment explored the effects of different proportions of sweet sorghum silage as a substitute for corn silage on dry matter intake (DMI), milk yield, milk quality, apparent digestibility, rumen fermentation parameters, serum amino acid profile, and rumen microbial composition of dairy cows. A total of 32 mid-lactation Holstein dairy cows with similar body weights and parities were randomly divided into four treatments: 100% corn silage +0% sorghum silage (CON), 75% corn silage +25% sorghum silage (CS1), 50% corn silage +50% sorghum silage (CS2), and 25% corn silage +75% sorghum silage (CS3). The milk yield was increased (linear, p = .048) as the proportion of sweet sorghum increased. Linear (p = .003) and quadratic (p = .046) increased effects were observed in milk fat as corn silage was replaced with sorghum silage. Compared with the CON diet group, the CS2 and CS3 diet groups had lower dry matter (DM) (linear, p < .001), ether extract (EE) (linear, p < .001), and gross energy (GE) (linear, p = .001) digestibility of the dairy cows. The ruminal fluid aspartate (Asp) level decreased (linear, p = .003) as the proportion of sweet sorghum increased. Linear (p < .05) and quadratic (p < .05) increased effects were observed for the contents of threonine (Thr), glycine (Gly), valine (Val), leucine (Leu), tyrosine (Tyr), and histidine (His) in rumen fluid with the replacement of corn silage with sorghum silage. Cows fed the CS3 diet had greater Faecalibacterium, Bacteroides, and Prevotella ruminicola content/copy number than those fed the CON diet (p < .05). In conclusion, feeding sorghum silage as a replacement for corn silage could increase the milk yield and fat, promote the growth of rumen microbes, and provide more rumen fluid amino acids for the body and microbial utilization. We believe that sorghum silage is feasible for dairy cows, and it is reasonable to replace corn silage with 75% sorghum silage.

Developmental Alterations of Colonic microRNA Profiles Imply Potential Biological Functions in Kid Goats.

The colon is a crucial digestive organ of the hind gut in ruminants. The bacterial diversity and mucosal immune maturation in this region are related to age. However, whether the microRNA expression in the colon of goats is affected by age is still unclear. In the current study, we analyzed the transcriptomes of colon microRNAs during preweaning (Day 10 and Day 25) and postweaning (Day 31). A total of 1572 microRNAs were identified in the colon tissues. Of these, 39 differentially expressed microRNAs (DEmiRNAs) and 88 highly expressed microRNAs (HEmiRNAs) were screened. The target genes regulated by the DEmiRNAs and HEmiRNAs were commonly enriched in the MAPK signaling pathway, Wnt signaling pathway, Hippo signaling pathway, cell adhesion molecules, focal adhesion, and adherens junction. Remarkably, the targeted genes of the DEmiRNAs were highly enriched for the prevention of microbial invasion via the Erbb-MAPK network while the targeted genes of HEmiRNAs contributed to the permeable barrier maintenance and cell damage surveillance. Additionally, there were eight different expression profiles of 87 dynamic miRNAs, in which approximately half of them were affected by age. Taken together, our study reveals the different roles of DEmiRNAs, HEmiRNAs, and dynamic microRNAs in the development of the colon and gives new insights into the regulatory mechanism of colon development in goats.

Elucidating the underlying mechanism of amino acids to regulate muscle protein synthesis: Effect on human health.

Maintaining muscle quality throughout life is crucial to human health and well-being. Muscle is the most extensive form of protein storage in the human body; skeletal muscle mass is determined by the balance between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). MPB provides amino acids needed by various organs; however, excessive MPB, especially with aging, may cause loss of muscle mass and a decline in motor function, even threatening life. The turnover of muscle protein is vital to the health of humans. Thus, although the study of MPS and MPB has theoretical and practical significance, the network that controls MPS is very complicated and we cannot discuss both MPS and MPB in a single review. Therefore, the aim of this review is to discuss the regulation of MPS, especially by amino acids. Amino acids regulate protein synthesis in cell and animal models, but compelling evidence for amino acids promoting protein synthesis in human muscles is ambiguous. Studies on the stimulation of human MPS by branched-chain amino acids (BCAAs) have been inconsistent. Amino acids other than BCAAs such as threonine and tryptophan may also have MPS-stimulating effects, and alternatives to BCAAs, such as ß-hydroxy-ß-methyl butyrate and branched-chain keto acids are also worthy of further investigation. Amino acids coordinate protein synthesis and degradation through the mechanistic target of rapamycin complex 1 (mTORC1); however, the amino acid-mTORC1-protein synthesis pathway is complex, and new insights into amino acid control continue to emerge. Understanding how amino acids control MPS is of forward-looking significance for treating muscle mass loss during human aging.

Dietary tea tree (Melaleuca alternifolia) oil supplementation enhances the expressions of amino acid transporters in goat ileal mucosa and improves intestinal immunity.

Tea tree oil (TTO) is a plant-derived additive with anti-inflammatory, bactericidal, and growth-promoting properties. However, little is known about the effects of TTO on intestinal amino acid transport and immune function in goats. Twenty-four Ganxi goats (initial body weight of 13.5 ± 0.70 kg) were randomly allotted two treatments and fed either control (CON) or CON+TTO (0.2 ml/kg) diet. The addition of TTO to the diet significantly decreased (p < .05) tumor necrosis factor-α content and increased (p < .05) interleukin-2 (IL-2) content in goat serum; significantly decreased (p < .05) IL-12, and increased (p < .05) IL-2 content in goat ileal mucosa; significantly increased (p < .05) secreted IgA content in the jejunal and ileal mucosa; significantly upregulated (p < .05) IL-2 and downregulated (p < .05) IL-12 at the mRNA level in the ileal mucosa; significantly elevated the levels of serine, arginine, and total amino acids in the ileal mucosa (p < .05); significantly upregulated (p < .05) SLC1A1 and SLC7A1 in the ileum; and significantly enhanced (p < .05) the protein expression of Claudin-1 in the ileal mucosa. In summary, adding 0.2 ml/kg of TTO to the diet enhanced SLC1A1 and SLC7A1 mRNA expression in the ileal mucosa, and SLC1A1 and SLC7A1 could transport serine and arginine from the chyme to the ileal mucosa. Thus, increased serine and arginine content in the mucosa could improve intestinal immunity. TTO supplementation upregulated the expression of IL-2 and Claudin-1 in goat ileal mucosa, and enhanced immune function in the intestine.

Effect of alfalfa substituted with ramie on the expression of apoptotic genes in the gastrointestinal tracts of goats.

The study investigated the effect of alfalfa hay substituted with ramie silage on the expression of apoptotic genes in the gastrointestinal tract of goats. Thirty-two goats were randomly allocated into four groups, in which the alfalfa was substituted with ramie at 0%, 35%, 75%, and 100% levels, respectively. In the rumen, the mRNA expression of Bax was significantly up-regulated (p = .0007) when alfalfa was 100% substituted by ramie; the mRNA expression of Bcl-2/Bax was significantly down-regulated (p = .02) when alfalfa was 100% substituted by ramie compared with the 75% substituted treatment; the protein expression of Bcl-xl was significantly down-regulated (p = .03) when alfalfa was 100% substituted by ramie compared with 35% and 75% substituted treatments, respectively. In the jejunum, the mRNA expression of p53 was significantly up-regulated (p = .01) when alfalfa was 100% substituted by ramie compared with 0% and 35% substituted treatments; the protein expression of p53 was significantly up-regulated (p = .001) when alfalfa was 35% substituted by ramie compared with 0% and 75% substituted treatments. However, the activity of Caspase-3 was not affected by different substituting levels of ramie in the rumen and jejunum of goats (p > .05). In conclusion, ramie with high substitution had strong antinutritional effect, which might promote the apoptosis in the gastrointestinal tract of goats in a caspase-independent manner, thus affecting the growth and development of goat. It was suggested that ramie should not replace alfalfa more than 35% in the process of goat feeding.

Apoptosis of human cholangiocarcinoma cell lines induced by ß-escin through mitochondrial caspase-dependent pathway.

The study aimed to evaluate the effects of ß-escin on human cholangiocarcinoma cell lines (QBC939, Sk-ChA-1 and MZ-ChA-1) and to explore its mechanisms. Cell growth, cell cycle and apoptosis were investigated, respectively, by MTT assay, single PI and FITC/PI double-staining flow cytometry, and fluorescence microscopy. The protein expression was determined by western blotting. The study revealed that ß-escin inhibited cholangiocarcinoma cell growth in a dose- and time-dependent manner, and the cell cycle of QBC939 and Sk-ChA-1 cells was arrested in the G2/M phase, and MZ-ChA-1 cells in G1 phase. Apoptosis of the three cholangiocarcinoma cell lines induced by ß-escin was associated with the collapse of the mitochondrial membrane potential and the activation of caspase-3. The apoptotic effect of ß-escin was suppressed by pancaspase inhibitor z-VAD-fmk. Molecular dissection revealed that the antiapoptotic protein bcl-2 was down-regulated after cholangiocarcinoma cell lines were treated with ß-escin, while the protein levels of bax and p53 were unchanged. Apoptosis was accompanied by an increase in reactive oxygen species (ROS). These results suggest that ß-escin induces apoptosis of cholangiocarcinoma cells through an intrinsic mitochondrial caspase-dependent pathway, and the increase in the bax/bcl-2 ratio and ROS may play important roles in ß-escin-induced apoptosis of cholangiocarcinoma cells.

Alfalfa Silage Treated With Sucrose Has an Improved Feed Quality and More Beneficial Bacterial Communities.

Alfalfa silage is one of the main roughages in the production of dairy cow, which can provide nutrition with high quality to improve milk quality and production. Sucrose additions have been widely used to improve the silage quality. In this study, the effects of sucrose on the fermentation quality and bacterial communities of alfalfa silage were investigated here using 0, 0.5, and 1% sucrose ensiling treatments for 15, 30, and 60 days. The ensiling time significantly decreased the crude fiber content and increased the ammonia nitrogen, acetic acid content, and the relative abundance of Enterococcus in the silages. The 1% sucrose-treated silage at 60 days had the lowest neutral detergent fiber acid, acid detergent fiber, and crude fiber content and the highest relative feed value. Moreover, sucrose-treated silage contained less acetic acid, propionic acid, and butyric acid, and had a lower pH than the controls for each duration. Enterobacteriaceae, Klebsiella, and Enterococcus were the dominant genera in all groups, and the relative abundance of Enterococcus and Lactobacillus was higher in the 1% sucrose-treated group than in the control. These results suggested that sucrose supplementation could improve alfalfa silage quality and increase its beneficial bacterial content.

Substitution of ramie (Boehmeria nivea) for alfalfa in improving the carcass and meat quality of Liuyang Black goats.

Ramie (Boehmeria nivea) is noted for the production of a large biomass that has a high protein content and is rich in antioxidants. It may thus serve as a high-quality forage material to replace alfalfa and improve the meat quality of farmed animals. In this study, we evaluated the carcass characteristics and meat quality of goats when 0, 35%, 75%, and 100% of dietary alfalfa was replaced with ramie. Crude protein content (linear, P < 0.0001) and key muscle color values at 24 h after slaughter decreased with increasing ramie levels. The content of most individual amino acids, non-essential amino acids (NEAA), total amino acids (TAA), branched chain amino acids (BCAA), functional amino acids (FAA), and flavor amino acids (DAA) decreased (P < 0.05) with increasing dietary ramie. The diet in which 35% of alfalfa was replaced with ramie yielded meat with the highest amino acid content, whereas the fatty acid profile was unaffected by the inclusion of ramie. These results indicate that ramie could be used as a potential dietary forage resource for goats, and that substituting 35% of alfalfa with ramie, which is equivalent to 126 g/kg DM content, would be optimal in terms of goat meat quality.

Comparison of the Effects of Nonprotein and Protein Nitrogen on Apoptosis and Autophagy of Rumen Epithelial Cells in Goats.

Protein nutrition is particularly important for the self-renewal processes of gastrointestinal epithelial cells. The self-renewal of cells is inseparable from the interaction between apoptosis and autophagy. However, there are few reports on the relationship between different nitrogen sources and apoptosis/autophagy. In this study, the relative protein expression of Bcl-2-associated X protein(Bax), caspase-3, and p62 was significantly higher (p < 0.05), while that of Bcl-xl, Bcl-2, Beclin1, and Microtuble-associated protein light chain 3 (LC3-II) was significantly lower (p < 0.05), in the NH4Cl group in comparison with the NH4Cl + 4-phenylbutyric acid (4PBA) group. In addition, the relative protein expression of Bax and caspase-3 was significantly higher (p < 0.05), while that of Bcl-2 and Bcl-xl was decreased significantly (p < 0.05), in the NH4Cl + 3-Methyladenine (3-MA) group and the methionine (Met) + 3-MA group in comparison with the NH4Cl group. Furthermore, the relative protein expression of Beclin1 and LC3B-II was significantly lower (p < 0.05), while that of p62 was significantly higher (p < 0.05), in the NH4Cl + Z-VAD-FMK group and the Met + Z-VAD-FMK group in comparison with the NH4Cl group. In conclusion, our results suggested that endoplasmic reticulum (ER) stress played a critical role in the crosstalk between apoptosis and autophagy induced by NH4Cl and Met. Autophagy had a more obvious ameliorative effect on ruminal epithelial cell apoptosis after treatment with nonprotein nitrogen than after treatment with protein nitrogen. These findings may reveal the molecular mechanism of apoptosis and autophagy induced by nonprotein nitrogen and protein nitrogen.