Effects of Taurine on Broiler Aortic Endothelial Cells Activity and Antioxidant Ability Impired by Heat Stress In Vitro.

In order to provide a theoretical basis for the amelioration of heat stress-related diseases in broilers by taurine supplementation, the effect of taurine on the viability and antioxidant ability of aortic endothelial cells in broilers under heat stress was investigated in the present study. In this experiment, 10d healthy broilers were sacrificed, then aortic tissue was used for aortic endothelial cells isolation and cultivation. Tissue patching was used to cultivate primary broiler aortic endothelial cells. The 3rd to 5th generations of cells were used and randomly divided into five groups, including the control group (C), the heat-stressed group (HS), the Tau(HS + LTau) group, the Tau(HS + MTau) group and the Tau(HS + HTau) group. Cells were cultivated for 24 h in a cell incubator (37 °C, 5%CO2). Then heat-stressed cells were placed in a 43 °C thermostatic water bath for 6 h, followed by incubation in the cell incubator under 37°Cfor 1 h. The results were as follows (1) Based on MTT colorimetry and AO/EB staining, the activity of aortic endothelial cells was decreased, but the rate of apoptosis was increased in the HS group. Compared with the HS group, the taurine groups showed significantly higher level in relative survival rates (P < 0.05), and significantly lower apoptosis rates (P < 0.05); (2) compared to control group, LDH activity and MDA content of endothelial cells in the HS group were significantly increased (P < 0.01), while the levels of T-SOD, GSH-Px and T-AOC were significantly decreased (P < 0.01). The LDH activity and MDA content of endothelial cells were significantly lower in Tau group than those of HS group (P < 0.05), while the T-SOD activity, GSH-Px activity and T-AOC of endothelial cells were significantly increased (P < 0.05) in the taurine group. The results show that HS decreases antioxidant capacity, which causes severe oxidative damage to the endothelial cells; while taurine administration prevents the decline in LDH activity and MDA content, and increases the activity of several antioxidant enzymes, including SOD, GSH-Px and T-AOC, which implies that taurine can improve the broiler aortic endothelial cells activity and antioxidant ability under heat stress.

Taurine Improves Sexual Function in Streptozotocin-Induced Diabetic Rats.

Previous studies have identified that diabetic erectile dysfunction is associated with androgen and nitric oxide deficiency resulting from hyperglycemia. It has been demonstrated that taurine can stimulate testosterone secretion, increase nitric oxide synthase (NOS) activity and nitric oxide (NO) production, and reduce blood glucose levels in the diabetic animals. Furthermore, recent studies have found that taurine relaxes both the corpus cavernosum and the vasculature. Accordingly, we hypothesized that taurine might exert beneficial effects on erectile function of the diabetic rats. Here, we assessed the effects of taurine on sexual function in streptozotocin (STZ) -induced diabetic male rats. We observed that taurine treatment could markedly increase sexual response and mating ability of STZ-diabetic rats. The serum concentration of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) were also significantly increased by taurine administration. Importantly, taurine supplementation notably increased mRNA levels and activity of endothelial NOS (eNOS) and neuronal NOS (nNOS), as well as NO and cGMP content, in the corpus cavernosum of the diabetic rats. In conclusion, the present data indicate that taurine can increase sexual function of STZ-induced diabetic male rats mainly by correcting the diabetes, increasing sexual desire, which is implicated in ameliorating the hypothalamic-pituitary-testicular axis function, and by improving penile erection, which requires increased signaling from the penile endothelial- and neuronal-dependent NO-cGMP pathway.

Taurine Recovers Testicular Steroidogenesis and Spermatogenesis in Streptozotocin-Induced Diabetic Rats.

A great deal of investigations have verified that diabetic male reproductive impairment is associated with the dysfunction of testicular steroidogenesis and spermatogenesis resulted from insulin deficiency and hyperglycaemia-induced oxidative stress. It has been identified taurine is profitable for diabetes mellitus and diabetic implications through its insulin-like and islet cells protective activity. Furthermore, our previous studies found that taurine could increase testicular antioxidative ability, stimulate the endocrine activity of hypothalamic-pituitary-testicular axis, elevate testosterone level, raise sperm quality, suppress the deterioration of testicular function. Accordingly, we hypothesized that taurine may have beneficial effects on testicular dysfunction under diabetic mellitus status. Here, we investigated the effects of taurine on testicular steroidogenesis and spermatogenesis in streptozotocin (STZ)-induced type I diabetic rats. We observed that taurine treatment can markedly increase the body and testis weights, testicular SDH and G6PDH activities, decrease the serum fasting glucose concentration of diabetic rats. Serum contents of GnRH, LH, FSH, T, and testicular StAR, 3ß-HSD, 17ß-HSD mRNA expression levels were also obviously raised by taurine administration, indicating that taurine can improve testicular steroidogenesis in diabetic animals. Finally, we found taurine supplementation effectively elevated the sperm count and motility, reduced sperm abnormality, suggesting that taurine can increase the testicular spermatogenesis function of diabetic rat. In summary, the present data indicated that taurine can rescue the function of testicular steroidogenesis and spermatogenesis in STZ-induced type I diabetic rats possibly by increasing the endocrine activity of hypothalamic-pituitary-testicular axis.

Effects of Replacement of Methionine in Diets with Taurine on Growth Performance and Blood Index in Broilers.

We studied effects of replacement of methionine with taurine on growth performance and blood index of AA+ broilers. Six hundred 1 day broilers were divided into 5 groups, with 3 replicates of 40 broilers in each. The experiment lasted for 42 days.The control group were fed on formulated diets containing 2% methionine; the other groups were offered feed with equal nitrogen and calories to the control group, but contained 25, 50, 75 and 100% taurine in place of methionine.Compared with the control group, no significant differences were observed in growth performance of 1-21 days broilers, or the serum LDL-C, TC, IgG and SOD of the experimental groups (P> 0.05). ADG and F/G from days 1-42, ADG, ADFI and F/G from days 22-42 were significantly different between the experimental groups and the control group (P < 0.05). ADFI and Mortality in 50, 75 and 100% taurine groups were significantly different compared with the control group (P < 0.05). IgM and GSH-PX of 50 and 75% taurine groups were significantly different compared with the control group (P < 0.05). Serum HDL-C, T-AOC levels in 50, 75 and 100% taurine groups were significantly different compared with the control group (P < 0.05). Based on the quadratic regression analysis, the best replacement ratios were 58%, 61% and 61% on days 1-21, 22-42, and 1-42, respectively. In conclusion, appropriate levels of taurine supplement can improve growth performance, immune system, T-AOC, and lipid metabolism.

Taurine and Chinese traditional medicine accelerate alcohol metabolism in mice.

Excessive alcohol consumption is dangerous and causes serious damage to health. The main organ capable of alcohol oxidizing is liver which is also the main organ synthesizing taurine, a sulfur-containing ß-amino acid, which is the major free intracellular amino acid presenting in many tissues of human and animals and exerting many physiologic and pharmacologic functions. To investigate the effect of taurine and Chinese traditional medicine on alcohol metabolism after acute alcoholic intake, male Kunming mice were administered with 60% alcohol (0.4 ml) intragastrically. Water, taurine, or taurine coadministration with Chinese traditional medicine was intragastrically administered to mice 30 min before or after alcohol intake. The disappearance of body-righting reflex was used to determine the intoxication of mice. Durations between alcohol intake and intoxication (tolerance time), intoxication and recovery (maintenance time) were recorded. The concentration of blood alcohol, levels of hepatic alcohol dehydrogenase (ADH), and acetaldehyde dehydrogenase (ALDH) were detected at 20, 50, 90, 120, and 150 min after alcohol intake. The results showed that taurine administered alone or together with Chinese traditional medicine could both significantly reduce the number of intoxicated mice, postpone the tolerance time, shorten the maintenance time, and could obvisouly decrease blood level of alcohol, increase hepatic levels of ADH and ALDH. The results indicated that taurine administered alone or together with traditional Chinese medicine could significantly accelerate the metabolism of alcohol, reduce the toxicity of alcohol, and coadministration of taurine and traditional Chinese medicine had better effects.

Effects of taurine on male reproduction in rats of different ages.

BACKGROUND: It has been demonstrated that taurine is one of the most abundant free amino acids in the male reproductive system, and can be biosynthesized by male reproductive organs. But the effect of taurine on male reproduction is poorly understood. METHODS: Taurine and beta-alanine (taurine transport inhibitor) were offered in water to male rats of different ages. The effects of taurine on reproductive hormones, testis marker enzymes, antioxidative ability and sperm quality were investigated. RESULTS: The levels of T and LH were obviously increased by taurine supplementation in rats of different ages, and the level of E was also significantly elevated in baby rats. The levels of SOD, ACP, SDH and NOS were obviously increased by taurine administration in adult rats, but the levels of AKP, AST, ALT and NO were significantly decreased. The levels of SOD, ACP, LDH, SDH, NOS, NO and GSH were significantly elevated by taurine administration in aged rats, but the levels of AST and ALT were significantly decreased. The motility of spermatozoa was obviously increased by taurine supplement in adult rats. The numbers and motility of spermatozoa, the rate of live spermatozoa were significantly increased by taurine supplement in aged rats. CONCLUSIONS: The present study demonstrated that a taurine supplement could stimulate the secretion of LH and T, increase the levels of testicular marker enzymes, elevate testicular antioxidation and improve sperm quality. The results imply that taurine plays important roles in male reproduction especially in aged animals.