Effects of Taurine on Serum Indexes of Broilers with Chronic Heat Stress.

The aim of this study was to investigate the effects of taurine on tissue injury, protein metabolism, and basal metabolism of broilers after chronic heat stress by detecting serum physiological and biochemical indices. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5, 2, and 8 g/L taurine were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, the MTau group had significantly higher total serum protein content (P < 0.05), while the other groups were not significantly different (P > 0.05). The MTau and HTau groups had significantly lower serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all showed significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups thereafter (P > 0.05). Compared with HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). In conclusion, the effects of taurine on tissue damage, protein metabolism, and basal metabolism of broilers after chronic heat stress were studied by measuring serum physiological and biochemical indices. To provide a theoretical basis for the application of taurine in acute heat-stressed broilers.

Antioxidant Effect of Taurine on Chronic Heat-Stressed Broilers.

The purpose of this study was to investigate the effects of taurine on blood indices of broilers with chronic heat stress and to provide theoretical basis for the application of taurine in the anti-chronic heat stress of broilers. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5 g/L, 2 g/L, and 8 g/L taurine, were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, MTau significantly increased the total serum protein content (P < 0.05), but the other groups were not significantly different (P > 0.05). The MTau and HTau groups contained significantly lowered serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all exhibited significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups at other times (P > 0.05). Compared with the HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). Compared with the LTau, MTau, and HTau groups, serum MDA content was significantly increased in the heat-stressed broilers (P < 0.05). MTau group contained significantly increased T-AOC, SOD, CAT, and GSH-PX levels (P < 0.05). The other groups were not significantly different (P > 0.05). Compared with group C, serum HSP60 and HSP70 levels were significantly elevated in the HS group (P < 0.05). Compared with the HS group, the LTau and MTau groups contained significantly increased serum HSP60 and HSP70 concentrations (P < 0.05), but the other groups were not significantly different (P > 0.05). In conclusion, taurine can alleviate the symptoms of chronic heat stress of broilers, regulate the metabolism of the body, and improve the antioxidant activity of the body.

Drug resistance associates with activation of Nrf2 in MCF-7/DOX cells, and wogonin reverses it by down-regulating Nrf2-mediated cellular defense response.

Acquired resistance to doxorubicin (DOX) is a serious therapeutic problem in breast cancer patients. In this study, we investigated whether nuclear factor erythroid 2-related factor 2 (Nrf2) was associated with drug resistant in DOX resistant MCF-7 (MCF-7/DOX) cells, and if wogonin, a flavonoid isolated from the root of Scutellaria baicalensis Georgi, could reverse drug resistance in MCF-7/DOX cells. We found that the endogenous expression of Nrf2 as well as its target proteins heme oxygenase-1 (HO-1), NADP(H):quinone oxidoreductase (NQO) in MCF-7/DOX cells was higher than that in MCF-7 cells. Tert-butylhydroquinone treatment increased the expression Nrf2, HO-1, and NQO-1, and enhanced resistance of MCF-7 cells to DOX. Similarly, intracellular Nrf2 protein level was significantly decreased in MCF-7/DOX cells and DOX resistance was partially reversed by Nrf2 siRNA. Wogonin downregulated the Nrf2-dependent response and partly reversed DOX resistance in MCF-7/DOX cells. These results suggested that activation of Nrf2 was associated with drug resistance in MCF-7/DOX cells. Wogonin reversed drug resistance and its reversal mechanism might be due to the suppression of Nrf2 signaling pathway, indicating the feasibility of using Nrf2 inhibitors to increase efficacy of chemotherapeutic drugs.

Quantitative determination of diterpenoid alkaloid Fuziline by hydrophilic interaction liquid chromatography (HILIC)-electrospray ionization mass spectrometry and its application to pharmacokinetic study in rats.

A rapid, sensitive and specific hydrophilic interaction liquid chromatography coupled to electrospray ionization mass spectrometric (HILIC-MS) method for the quantification of Fuziline (15α-Hydroxyneoline) in rat plasma was developed and validated. After liquid-liquid extraction with ethyl acetate, Fuziline and Guanfu base A (internal standard) were separated with HILIC Chrom Matrix HP amide column (5µm, 10cm×3.0mm I.D.) with isocratic elution at a flow-rate of 0.2mL/min. The analytes were detected by using an electrospray positive ionization mass spectrometry in the selected ion monitoring (SIM) mode. A good linear relationship was obtained in the concentration ranging from 1 to 1000ng/mL (R(2)=0.999) with the lower limit of quantification (LLOQ) at 1ng/mL and limit of detection (LOD) at 0.5ng/mL. The average recoveries of Fuziline in plasma at the concentrations of 2, 50, 1000ng/mL ranged from 68.2 to 69.9%. Intra- and inter-batch relative standard deviations ranged from 1.5 to 3.3% and 2.6 to 8.3%, respectively. Fuziline was stable under different sample storage and processing conditions except three-cycle freeze-thaw treatment at 2ng/mL. This method was successfully applied to the pharmacokinetic studies in Sprague-Dawley rats. The absolute bioavailability of Fuziline after oral administration 4mg/kg Fuziline in rats was 21.1±7.0%, with clearance rate at 1745.6±818.1mL/kg/h, and half-life at about 6.3±2.6h.

The role of Nrf2 and apoptotic signaling pathways in oroxylin A-mediated responses in HCT-116 colorectal adenocarcinoma cells and xenograft tumors.

Oroxylin A is a flavonoid found in the roots of Scutellaria baicalensis Georgi, a herbal medicine commonly used as an antipyretic, analgesic, antitumor, and anti-inflammatory agent. It has recently been investigated for its anticancer activities in hepatoma, gastric, and breast tumors. Here, we investigated the antitumor effects of oroxylin A in human colon carcinoma HCT-116 cells in vitro and in vivo. We characterized the proapoptotic effect of oroxylin A using diamidino-phenyl-indole (DAPI) and annexin V/PI staining. We then found that both caspase-3 and caspase-9 were activated, the expression of Bcl-2 protein decreased, and the expression of Bax protein increased after treatment with oroxylin A. In addition, oroxylin A increased nuclear transcription factor erythroid-related factor 2 (Nrf2) expression and induced Nrf2 translocation into the nucleus. Furthermore, we found that oroxylin A treatment elevated intracellular reactive oxygen species levels and increased the protein expression level of two of the Nrf2 target genes heme oxygenase-1 and NADP(H):quinone oxidoreductase-1 in HCT-116 cells. Finally, our study demonstrated that oral administration of oroxylin A significantly decreased tumor volume and weight in immunodeficient mice that were inoculated with HCT-116 cells. The in-vivo chemopreventive efficacy of oroxylin A against HCT-116 human colon cancer was accompanied by its proapoptotic and Nrf2-inducing activities, which correlates with the in-vitro study. This is the first demonstration of oroxylin A-dependent chemoprevention in colon cancer and may offer a potential mechanism for its anticancer action in vivo.