Effects of N-carbamylglutamate and L-arginine on gonadotrophin-releasing hormone (GnRH) gene expression and secretion in GT1-7 cells.

Recent studies have shown that N-carbamylglutamate (NCG) and arginine (ARG) supplementation improves reproductive performance in livestock. The objectives of the present study were to evaluate the effects of NCG and ARG on GT1-7 cell gonadotrophin-releasing hormone (GnRH) secretion, gene expression and cell proliferation. GT1-7 cells were treated in vitro with different concentrations of NCG (0-1.0mM) or ARG (0-4.0mM) in serum-free medium for 12 or 24h. For GnRH secretion and cell proliferation, GT1-7 cells were more sensitive to NCG than ARG. NCG treatment after 12h increased cell numbers and inhibited GnRH secretion in a dose-dependent manner (P<0.05), although there was no significant effect of NCG on these parameters after 24h culture. ARG treatment decreased GnRH secretion after 24h (P<0.05), whereas it had no effect after 12h. GT1-7 cells express GnRH, Kiss-1 metastasis-suppressor (Kiss1), G-protein coupled receptor 54 (GPR54), neuronal nitric oxide synthase (nNOS) and estrogen receptor α (ERα) genes. High concentrations of NCG (1.0mM) and ARG (4.0mM) inhibited (P<0.05) GnRH and nNOS mRNA abundance in GT1-7 cells. ARG treatment decreased Kiss1 and increased ERα mRNA abundance. Thus, high concentrations of NCG (1.0mM) and ARG (4.0mM) may act both directly and indirectly to regulate GnRH neuron function by downregulating genes related to GnRH synthesis and secretion to slow GnRH production while stimulating GT1-7 cell proliferation.

Insulin in combination with selenium inhibits HG/Pal-induced cardiomyocyte apoptosis by Cbl-b regulating p38MAPK/CBP/Ku70 pathway.

OBJECTIVE: In this study, we investigated whether insulin and selenium in combination (In/Se) suppresses cardiomyocyte apoptosis and whether this protection is mediated by Cbl-b regulating p38MAPK/CBP/Ku70 pathway. MATERIALS AND METHODS: Firstly, H9c2 cardiomyocytes were treatment with high glucose (25 mmol/L) and palmitate (600 µmol/L) (HG/Pal). Next, H9c2 cardiomyocytes were treatment with HG/Pal+In/Se (10 nmol/L Insulin in combination with 10 nmol/L selenium). Finally, cells were treated with siRNA against Cbl-b, followed by HG/Pal and HG/Pal+In/Se treatment. Then, Cell apoptosis was observed by flow cytometry (FCM). The levels of Cbl-b, p-p38MAPK, CBP and Bax were examined by Western blotting. The acetylated Ku70 was detected by immunoprecipitation. RESULTS: Insulin and selenium in combination reduced cell apoptosis, up-regulated Cbl-b expression, down-regulated p38MAPK, CBP and acetylated Ku70 expressions and prevented Bax translocation, whereas Cbl-b knockdown strongly suppressed In/Se-induced these effects in HG/Pal-treated cardiomyocytes. CONCLUSIONS: Insulin and selenium synergistically suppressed cardiomyocyte apoptosis by Cbl-b regulating p38MAPK/CBP/Ku70 pathway.

Effects of dietary glutamine and gamma-aminobutyric acid on meat colour, pH, composition, and water-holding characteristic in broilers under cyclic heat stress.

1. An experiment was conducted to evaluate the effects of dietary glutamine (Gln, 0 and 5 g/kg) and gamma-aminobutyric acid (GABA, 0 and 100 mg/kg) on raw breast meat colour, pH, composition and water-holding characteristic of broilers under cyclic heat stress (HS). 2. A total of 360 21-d-old Arbor Acres male chicks were randomly assigned to 5 treatment groups (6 replicates of 12 birds per cage). The positive control (PC) broilers were kept in a thermoneutral chamber (22-24°C) and fed on the basal diet. The other 4 groups were kept in a cyclic HS chamber (30-34°C) for 9 h (from 09:00 to 18:00). 3. A significant increase was observed in breast meat lightness at 28, 35 and 42 d; and pH values at 28, 35 and 42 d; while a significant decrease was observed in breast meat cooking loss (CL) and contents of moisture, crude protein (CP), crude fat (CF) and crude ash (CA) due to HS. 4. The supplementation with 0·5 g Gln/kg decreased lightness at 28, 35 and 42 d; while increasing redness at 28 d, yellowness at 35 d, contents of CP, CF and CA, thawing loss (TL) and drip loss (DL). The addition of 100 mg GABA/kg decreased lightness at 28 and 35 d, pH value at 28, 35 and 42 d, and TL; while increasing redness at 28 d, 35 and 42 d, contents of moisture, CP and CF. 5. The lightness, redness, and pH value; contents of moisture, CP, CF and CA; and TL, DL and CL of breast meat of broilers fed with the mixture of Gln and GABA under cyclic HS were similar to those of the broilers in the PC group. 6. Significant interactions were found between Gln and GABA for yellowness at 28 and 35 d; pH at 28, 35 and 42 d; moisture content, CP content, water-holding capacity and TL. 7. These results demonstrated that dietary Gln and GABA offer a potential nutritional strategy to prevent cyclic HS-related depression in broiler meat chemical composition and quality.

[Experimental study on effect of xinkang oral liquid on coxsackie B3 viral myocarditis in mice].

OBJECTIVE: To study the therapeutic effect of Xinkang Oral Liquid (XKOL) in treating acute Coxsackie B3 viral myocarditis in mice. METHODS: Viral myocarditis model was established by intraperitoneal inoculation with Coxsackie B3 virus. Mice were randomly divided into 4 groups randomly, the model group, the positive control group (treated with Ribavilin), the XKOL group and the normal control group. Body weight of mice was weighed at the 5th, 10th and 20th day. Weight, macro- and histopathologic changes of heart were observed by microscope and measured by morphometric quantification, and the data were treated statistically. RESULTS: In the XKOL group, the body weight of mice increased, the degree of myocardial necrosis mild and small in size, which has been repaired more completely, the antiviral effect was found in XKOL group. CONCLUSION: XKOL has definite therapeutic effect on viral myocarditis, its effect is better than Ribavilin in protecting myocardium and anti-virus.

[Studies on the chemical constituents of the leaves of Lantana camara].

Six compounds were isolated from leaves of Lantana camara. On the basis of chemical and spectral (UV, IR, EI-MS, 1HNMR 13CNMR) analysis, they were identified as oleanonic acid (I), lantadene A (II), lantadene B (III), lantanilic acid (IV), icterogenin (V) and 4',5-dihydroxy-3,7-dimethoxyflavone-4'-O-beta-D-glucopyranoside (VI). VI is a new compound named camaroside.