Growth Performance, Nutritional And Physiological Effects Of Cysteamine In Animals

Three experiments were conducted to investigate growth performance, nutritional and physiological effects of cysteamine in animals.Exp.l A total of 14 female Sprague-Dawley rats were randomly assigned to one of two groups, with 7 rats per group. One group was given doses of 150 mg/kg body weight cysteamine intraperitoneally. The other group was given physiological saline as control. Collections of urine were made at 0-8 and 8-24 hours and collections of blood were made at 24 hours after the last injection. The 1H NMR spectra were acquired for each sample. PC A or OSC-PLS was performed on all data. The results indicated that①Acute CS supplementation also changed microbial metabolites concentration (increasing the concentrations of serum acetate and urine dimethylamine, and reducing urine hippuric acid concentration (0～8 hours)).②Acute CS also changed TCA metabolites (increasing the concentration of urine a-ketoglutaric acid (0～8 hours), reducing the concentration of urine succinic acid, citric acid), decreased the concentration of urine glucose(0～8 hours)).③Acute CS also affected the metabolism of nitrogen (increasing the concentration of urine creatinine,2-methylglycine (0-8 hours), creatine (8～24 hours) and serum glycine and reducing the concentration of creatine in urine (0～8 hours)).④Acute CS also affected the fat metabolism (reducing the concentration of serum lipoprotein, HDL, VLDL, FA, PUFA, UFA, phosphorylcholine) Conclusion:Acute CS supplementation changed animal and microorganisms metabolism, decreased energy metabolism, increased nitrogen metabolism and decreased fat incretion.Exp.2 A total of 20 female SD rats were randomly assigned to one of two groups, with 10 rats per group for 25 days. One group was given doses of 150 mg/kg body weight cysteamine intraperitoneally (biweekly, Monday and Thursday). The other group was given physiological saline intraperitoneally as control. Collections of urine were made at 0-8 and 8-24 hours and collections of blood were made at 24 hours after the last injection. The1H NMR spectra were acquired for each sample. PCA or OSC-PLS was performed on all data. The results indicated that ①Chronic CS supplementation changed microbial metabolites concentration (decreasing serum concentrations of acetate, ethanol, trimethylamine oxide, betaine hippuric acid and urine concentration of trimethylamine oxide; increasing the concentration of dimethylamine in urine).②Chronic CS changed TCA metabolites (decreasing the concentration of urine succinic acid and reducing the concentration of urine citric acid (8～24 hours)) and decreased the glucose in urine.③Chronic CS affected the metabolism of nitrogen (increasing the concentration of urine dimethylglycine, creatinine (0 to 8 hours), creatine (8～24 hours) and glycine in urine or serum; reducing the concentration of urine creatinine (8～24 hours) and 3-methylhistidine).④Chronic CS affected the metabolism of fat (increasing concentration of serum HDL and decreasing the concentration of UFA, VLDL, lipoprotein in urine or serum). Conclusion:Chronic CS changed serum and urine metabolome in rats. Chronic CS decreased energy metabolism (Tricarboxylic acid cycle) and protein breakdown rate. CS can modulate amino acid and carbohydrates metabolism from microbes in animals.Exp.3 A total of 24 finishing pigs (60.05±1.24 kg; 12 gilts and 12 barrows) were assigned randomly to one of the three dietary groups, with four pens/group (per pen:one gilt, one barrow). The pigs were fed a basal diet containing 0 (control),70 or 140 mg/kg cysteamine feed additive for 47 days. The results indicated that①the ADG and ADFI (70 mg/kg) were increased (P<0.05) by 19.5%,15.2%, respectively; however, the ADG and ADFI (140 mg/kg) and feed efficiency were not affected.②CS supplementation (70 mg/kg) increased serum IGF-I level, upregulated mRNA levels of GHR and IGF-I (liver, stomach, muscle), IGF-IR (stomach, duodenum, muscle) and IGFBP-3 (liver), but downregulated IGFBP-3 (stomach, duodenum, muscle). CS supplementation (70 mg/kg) did not affect mRNA levels of GHR and IGF-I (duodenum), IGF-IR (liver), and IR (liver, stomach, duodenum, muscle).③CS supplementation (140 mg/kg) downregulated GHR (duodenum), IGF-I and IGF-IR mRNA (liver, stomach, duodenum, muscle), but upregulated IGFBP-3 and IR mRNA (liver, stomach, duodenum, muscle) and did not affect ADG, and serum IGF-I concentration. Conclusion:the results suggest that dietary CS supplementation modulates the growth rate, serum IGF-I concentrations, and the gene expression of GHR, IGF-I, IGF-IR, IGFBP-3, and IR in a dose-dependent manner. CS supplementation has tissue-specific regulation of GHR, IGF-I, IGF-IR, and IGFBP-3 mRNA levels. Moreover, the results also imply the physiologic role of the GH-IGF axis in mediating the dietary CS supplementation-supported growth of finishing pigs.Collectively, Chronic CS is better than acute CS in modulating microbe metabolism. CS can decrease energy metabolism (Tricarboxylic acid cycle), decrease fat incretion and protein breakdown rate, modulate amino acid and carbohydrates metabolism from microbes and thus mediate the dietary CS supplementation-supported growth of animals through GH-IGF axis.