AIMTo know the effect of cysteamine (CS) on the plasma levels of somatostatin (SS) and some metabolic hormones in adult geese.

METHODSFourteen adult crossbred geese (Chuan white x Tai lake) fitted with chronic wing vein cannulas were used in this study to evaluate the effect of CS on SS, TSH, T3 and T4 levels. The experiment was consisted of control and treated phase. The diet was added CS at dosage of 100 mg/kg bw on the first day of the treated phase. The blood samples were collected from the cannulas and analyzed by radioimmunoassay.

RESULTSThe plasma SS concentration was (1.87 +/- 0.10) microg/L in control phase. Whereas SS concentrations on day 1, 3, 5, 7 of treated phase were decreased markedly (P < 0.05 or P < 0.01). Thereafter it was rose on the seventh day, however it was still lower than that of control. The thyroid stimulating hormone (TSH) content (2.45 +/- 0.31 mIU/L) was significantly decreased by 21.63% (P < 0.01) on day 1, and 18.37% (P > 0.05) on day 3 and day 5. Comparing with control phase (5.41 +/- 0.98 microg/L), T4 contents were elevated by 60.26% (P < 0.01), 43.25% (P < 0.01), 37.15% (P < 0.01) and 16. 82% (P < 0.01) respectively on day 1, 3, 5, 7. T3 level was (1.05 +/- 0.06) microg/L in control phase, whereas the levels was significantly increased by 36.19% (P < 0.01) on day 3. Also, the insulin concentration was higher than that of control (4.43 +/- 0.41 mU/ L) by 18.28% (P < 0.05) on the day 5.

CONCLUSIONThese results indicate that CS can decrease the plasma SS and TSH levels, whereas increase the levels of T4, T3 and insulin, therefore change metabolism, improve the nutrition transform and accelerate the growth in geese.

Animals ; Cysteamine ; pharmacology ; Diet ; Geese ; Insulin ; blood ; Somatostatin ; blood ; Thyrotropin ; blood ; Thyroxine ; blood ; Triiodothyronine ; blood

AIMTo know the effect of cysteamine on the pancreatic secretion and enzyme activity in geese.

METHODSEight adult geese fitted chronic pancreatic and duodenal cannulas were used to evaluate the effect of cysteamine (CS) on the pancreatic secretion and enzyme activity. The experiment was consist of control and treated phase. CS was added in the diet at the dosage of 100 mg/kg bw on the first day of treated phase. The birds were free fed at daytime (8:00-20:00) and fasted at nighttime (20:00-8:00). The pancreatic juice samples were collected continuously for three days in each phase.

RESULTSCS increased the average rate of pancreatic secretion by 240.16% (P < 0.01), in which that of daytime was elevated by 234.45% (P < 0.01), while that of nighttime elevated by 253.70% (P < 0.01). The secretion volume at daytime was more than that of night. CS increased trypsin activity by 49.05% (P < 0.01), whereas lipase and amylase activity was reduced by 25.44% (P < 0.01) and 21.95% (P < 0.01) separately. The one hour total activity of trypsin, lipase and amylase were elevated by 406.88% (P < 0.01), 153.58% (P < 0.01) and 166.59% (P < 0.01) respectively. Ratios of pancreatic secretion were different between day and night.

CONCLUSIONThese results indicate that CS can affect the pancreatic juice secretion and pancreatic enzyme activity by depleting the somatostatin, so that benefits to improve the digestive foundation and supply more nutrition for quickly growing in geese.

Animals ; Cysteamine ; pharmacology ; Geese ; physiology ; Pancreas ; drug effects ; enzymology ; secretion ; Pancreatic Juice ; secretion ; Pancreatin ; metabolism

AIMTo investigate the effects of cysteamine compound (Lactonin) on milk production of late-lactating cows during hot summer when the temperature humidity index (THI) was higher than 76 and cows were suffered from heat stress.

METHODSIn this experiment 96 black and white dairy cows, based on milk yield (M) prior to the experiment, were assigned into 4 groups (G): G1 (M < 24 kg/d), G2 (24 < M< 28 kg/d), G3 (28 < M < 32 kg/d) and G4 (M > 32 kg/d). Each group (n = 24) was further divided into subgroups of Lactonin (3000 U/d) treatment (LT, n = 49) and control (n = 47).

RESULTSIn G1 of LT, the rectal temperature decreased (P < 0.05), milk yield, fat-corrected milk, milk fat and feed conversion rate (FCR) increased (P < 0.05). These were companied with trendy of higher milk protein and lower somatic cell count. With whole LT cows (n = 49), the mean milk fat (%) increased (P < 0.05), mean milk protein tended to increase, and the mean milk yield and FCM tended to be enhanced. Plasma T3, T4 tended to decline whereas insulin enhanced (P < 0.01) significantly in LT herd (n = 49).

CONCLUSIONLactonin helps heat-stressed cow to maintain a more normal metabolism in hot summer. This positive effect of Lactonin on cow performance is associated with Lactonin-dependent alteration of plasma insulin, T3 and T4.

Animals ; Cattle ; Cysteamine ; pharmacology ; Female ; Hot Temperature ; Lactation ; Milk ; secretion ; Seasons

To determine whether exocrine pancreatic secretion is regulated by endogenous somatostatin, somatostatin deficiency was induced by cysteamine. Rats were subcutaneously administered a single dose of cysteamine (30 mg/100 g body weight) 12 hr before experiment. Anesthetized rats were prepared with cannulation into bile duct, pancreatic duct, duodenum, and jugular vein and pancreatic juice was collected. For in vitro study, isolated pancreata of rats, pretreated with cysteamine, were perfused with an intraarterial infusion of Krebs-Henseleit solution (37 degrees C) at 1.2 mL/min, and pancreatic juice was collected in 15-min samples. In vivo experiment of the rat, the mean basal pancreatic secretions, including volume, bicarbonate, and protein output were significantly increased from 18.4+/-0.5 microL/30 min, 0.58+/-0.05 microEq/30 min, and 214.0+/-26.1 microg/30 min to 51.6+/-3.7 microL/30 min, 1.52+/-0.11 microEq/30 min, and 569.8+/-128.9 microg/30 min, respectively (p<0.05). In the isolated perfused pancreas, cysteamine also resulted in a significant increase in basal pancreatic secretion (p<0.05). Simultaneous intraarterial infusion of octreotide (10 pmol/hr) to isolated pancreata partially reversed the effect of cysteamine on basal pancreatic secretion. These findings suggest that endogenous somatostatin play an important role on the regulation of basal pancreatic exocrine secretion.
Animal ; Cysteamine/pharmacology* ; Hormone Antagonists/pharmacology* ; Hormones, Synthetic/pharmacology ; In Vitro ; Male ; Octreotide/pharmacology ; Pancreas/secretion ; Pancreas/drug effects* ; Perfusion ; Rats ; Rats, Sprague-Dawley ; Somatostatin/antagonists & inhibitors*

The treatment of cystamine, a transglutaminase (TGase) inhibitor, has beneficial effects in several diseases including CAG-expansion disorders and cataract. We compared the inhibition characteristics of cystamine with those of cysteamine, a reduced form of cystamine expected to be present inside cells. Cystamine is a more potent inhibitor for TGase than cysteamine with different kinetics pattern in a non- reducing condition. By contrast, under reducing conditions, the inhibitory effect of cystamine was comparable with that of cysteamine. However, cystamine inhibited intracellular TGase activity more strongly than cysteamine despite of cytoplasmic reducing environment, suggesting that cystamine itself inhibits in situ TGase activity by forming mixed disulfides.
Cell Line, Tumor ; Comparative Study ; Cystamine/*pharmacology ; Cysteamine/*pharmacology ; Enzyme Inhibitors/*pharmacology ; Humans ; Research Support, Non-U.S. Gov't ; Transglutaminases/*antagonists & inhibitors

OBJECTIVETo investigate the transduction efficiency of purified PEP-1-CAT fusion protein into rat heart and the protective effect of the fusion protein against myocardial ischemia-reperfusion injury.

METHODSPEP-1-CAT or CAT (500 microg) was injected in SD rats via the caudal vein, using normal saline as the control, and the hearts were harvested at 0.5, 1, 2, 4, 8, and 24 h after the injection. The transduction efficiency was evaluated by immunofluorescence technique, and the CAT activity was measured. Forty rats were randomized into 5 groups, namely the sham-operated group, ischemia-reperfusion group, and 3 PEP-1-CAT -treated groups (100, 300, and 500 microg). The left main coronary artery was occluded for 1 h followed by a 2-h reperfusion, and at the end of reperfusion, serum LDH and CK and MDA content in the myocardium were measured.

RESULTSNo green fluorescence was observed in saline group or CAT group. Bright green fluorescence was observed in PEP-1-CAT groups at different time points, most conspicuous at 8 h. No significant difference in CAT activity was found between CAT group and saline group (P>0.05); with the lapse of time, CAT activity in PEP-1-CAT group increased gradually, reaching the peak level at 8 h, which was 4.2 folds of that in the saline group. LDH ,CK and MDA were significantly lower in PEP-1-CAT- groups than in ischemia-reperfusion group (P<0.01).

CONCLUSIONPEP-1 can mediate the transduction of CAT in rat heart in a time-dependent manner, and PEP-1-CAT preconditioning provides a protective effect against ischemia- reperfusion injury in rats.

Animals ; Catalase ; metabolism ; pharmacology ; Cysteamine ; analogs & derivatives ; metabolism ; pharmacology ; Ischemic Preconditioning, Myocardial ; Male ; Myocardial Reperfusion Injury ; metabolism ; pathology ; prevention & control ; Peptides ; metabolism ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; pharmacology ; Transduction, Genetic

Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a tumor suppressor. Although it is well known to have various physiological roles in cancer, its inhibitory effect on inflammation remains poorly understood. In the present study, a human PTEN gene was fused with PEP-1 peptide in a bacterial expression vector to produce a genetic in-frame PEP-1-PTEN fusion protein. The expressed and purified PEP-1-PTEN fusion protein were transduced efficiently into macrophage Raw 264.7 cells in a time- and dose- dependent manner when added exogenously in culture media. Once inside the cells, the transduced PEP-1-PTEN protein was stable for 24 h. Transduced PEP-1-PTEN fusion protein inhibited the LPS-induced cyclooxygenase 2 (COX-2) and iNOS expression levels in a dose-dependent manner. Furthermore, transduced PEP-1-PTEN fusion protein inhibited the activation of NF-kappa B induced by LPS. These results suggest that the PEP-1-PTEN fusion protein can be used in protein therapy for inflammatory disorders.
Animals ; Cell Line ; Cyclooxygenase 2/*metabolism ; Cysteamine/*analogs & derivatives ; Enzyme Activation ; Humans ; Lipopolysaccharides/*pharmacology ; Macrophages/*metabolism ; Mice ; NF-kappa B/metabolism ; Nitric Oxide/*biosynthesis ; Nitric Oxide Synthase Type II/metabolism ; PTEN Phosphohydrolase/*genetics ; Peptides/*genetics ; Recombinant Fusion Proteins/*biosynthesis/genetics ; Signal Transduction