Animals ; Carbon Tetrachloride Poisoning ; Diabetes Mellitus, Experimental ; complications ; Liver Cirrhosis, Experimental ; chemically induced ; complications ; pathology ; Male ; Rats ; Rats, Sprague-Dawley

The injection of streptozotocin(stz) at a high dose (60 mg/kg) into young male rats produces direct beta cell destruction and leads to insulin dependent diabetes (IDD). In contrast the injection of multiple smal doses of stz (40 mg/Kg/d for 5 days) produce IDD, which resembles type l diabetes in man. The provocative effects of the pertussis vaccine (PV) and cyclosporin(CA) against the development of IDD induced by stz were studied. When PV in a dose of 3.75 X 10(10) microorganism was administered to single or multiple stz treated rats, hyperglycemia still developed and persisted during the experiment. No difference was noted in blood glucose levels, but plasma insulin levels were higher in PV treated rats. When CA (10 mg/kg) was administered daily to single or multiple stz treated rats, hyperglycemia seemed to be lower, but this was not statistically significant, however, plasma insulin levels were higher in CA treated rats. The results of this experiment suggest that PV and CA provide some protection to the beta cells of the pancreas.
Animal ; Blood Glucose/metabolism ; Cyclosporins/pharmacology* ; Diabetes Mellitus, Experimental/prevention & control* ; Diabetes Mellitus, Insulin-Dependent/chemically induced ; Male ; Pertussis Vaccine/pharmacology* ; Rats ; Rats, Inbred Strains

OBJECTIVETo get a better understanding of the mechanisms underlying type 1 diabetes mellitus, the differentially expressed pancreatic proteins from multiple low-dose streptozotocin (MLD-SIZ) mouse and normal mouse were analyzed and compared.

METHODS20 male rats were separated into 2 groups (n=10): model mice treated with MLD-STZ and normal mice,differences of pancreatic proteome among in the two groups of mice, were analyzed by two dimensional polyacryamide gel electrophoresis (2DE). Protein quantification was analyzed and the differentially expressed spots were identified using mass spectrometry and MASCOT database searching.

RESULTSCompared with control group, 23 proteins had changed significantly in the model group, 8 proteins expression were up-regulated, 15 proteins expressions down-regulated significantly. Using MALDI-TOF-MS, 15 proteins with significant change were identified by peptide fingerprinting map and the results were searched in MASCOT database. The function analyzed showed that proteins with change were associated with metabolic, anti-oxidant, structural, catalytic enzymes and chaperone, et al.

CONCLUSIONType 1 diabetes is probably exerted via multi-target and multi-path mechanism. The proteins with significant change are newly target for type 1 diabetes early diagnosis and treatment.

Animals ; Diabetes Mellitus, Experimental ; physiopathology ; Diabetes Mellitus, Type 1 ; chemically induced ; metabolism ; physiopathology ; Male ; Mice ; Pancreas ; metabolism ; Proteins ; metabolism ; Proteomics ; methods ; Streptozocin

OBJECTIVETo determine the optimal dosing of streptozotocin (STZ) for establishing lymphoma-bearing diabetic mouse models.

METHODSA total of 200 healthy male Balb/c mice were randomized into 4 groups (n=50) for intraperitoneal injection of a single dose of vehicle solution (control) or 75, 150, or 200 mg/kg STZ. The changes of body weight and blood glucose were observed regularly, and the success rate of modeling, mortality rate, and survival of the mice were recorded after the injections. The mice with successfully induced diabetes received subcutaneous or tail vein injection of A20 lymphoma cells, and the rate of tumorigenesis, mortality rate, and survival time were observed at 1 month and 3 months after tumor cell injection.

RESULTSCompared with the control group, the mice receiving STZ injection at 150 and 200 mg/kg showed significantly decreased body weight and increased blood glucose (P<0.05), while STZ at 75 mg/kg did not produced such obvious changes. STZ injection at 200 mg/kg resulted in a significantly higher mortality rate and shorter survival time than STZ at 150 mg/kg (P<0.05). In the control group and 150 and 200 mg/kg STZ groups, the rate of tumorigenesis or mortality rate showed no significant differences after subcutaneous injection of A20 lymphoma cells (P>0.05), but differed significantly at 3 months after tail vein injection of the tumor cells (P<0.05).

CONCLUSIONIntraperitoneal injection of STZ at 150 mg/kg is associated with a low mortality rate, a high successful modeling rate of diabetes and a long survival time in mice, and is therefore optimal for establishing diabetic mouse models bearing transplanted tumors.

Animals ; Blood Glucose ; Body Weight ; Diabetes Mellitus, Experimental ; Diabetes Mellitus, Type 2 ; chemically induced ; Injections ; Male ; Mice ; Mice, Inbred BALB C ; Streptozocin ; administration & dosage

The hippocampus is affected by various stimuli that include hyperglycemia, depression, and ischemia. Calcium-binding proteins (CaBPs) have protective roles in the response to such stimuli. However, little is known about the expression of CaBPs under diabetic conditions. This study was conducted to examine alterations in the physiological parameters with type 1 diabetes induced with streptozotocin (STZ) as well as time-dependent changes in the expression of two CaBPs changes of were being evaluated. Rats treated with STZ (70 mg/kg) had high blood glucose levels (>21.4 mmol/L) along with increased food intake and water consumption volumes compared to the sham controls. In contrast, body weight of the animals treated with STZ was significantly reduced compared to the sham group. CB-specific immunoreactivity was generally increased in the hippocampal CA1 region and granule cell layer of the dentate gyrus (DG) 2 weeks after STZ treatment, but decreased thereafter in these regions. In contrast, the number of PV-immunoreactive neurons and fibers was unchanged in the hippocampus and DG 2 weeks after STZ treatment. However, this number subsequently decreased over time. These results suggest that CB and PV expression is lowest 3 weeks after STZ administration, and these deficits lead to disturbances in calcium homeostasis.
Animals ; Calbindin 1/*genetics/metabolism ; Diabetes Mellitus, Experimental/*chemically induced ; Diabetes Mellitus, Type 1/*chemically induced ; *Gene Expression Regulation ; Hippocampus/*metabolism ; Male ; Parvalbumins/*genetics/metabolism ; Rats ; Rats, Wistar ; Streptozocin/administration & dosage

Type 1 diabetes is a common metabolic disorder accompanied by increased blood glucose levels along with glucocorticoid and cognitive deficits. The disease is also thought to be associated with environmental changes in brain and constantly induces oxidative stress in patients. Therefore, glucocorticoid-mediated negative feedback mechanisms involving the glucocorticoid receptor (GR) binding site are very important to understand the development of this disease. Many researchers have used streptozotocin (STZ)-treated diabetic animals to study changes in GR expression in the brain. However, few scientists have evaluated the hyperglycemic period following STZ exposure. In the present study, we found GR expression in the hippocampus varied based on the period after STZ administration for up to 4 weeks. We performed immunohistochemistry and Western blotting to validate the sequential alterations of GR expression in the hippocampus of STZ-treated type 1 diabetic rats. GR protein expression increased significantly until week 3 but decreased at week 4 following STZ administration. GR expression after 70 mg/kg STZ administration was highest at 3 weeks post-treatment and decreased thereafter. Although STZ-induced increase in GR expression in diabetic animals has been described, our data indicate that researchers should consider the sequential GR expression changes during the hyperglycemic period following STZ exposure.
Animals ; Diabetes Mellitus, Experimental/chemically induced/*metabolism/*physiopathology ; Disease Models, Animal ; *Gene Expression Regulation ; Hippocampus/metabolism/*physiopathology ; Humans ; Male ; Rats ; Rats, Wistar ; Receptors, Glucocorticoid/*genetics/*metabolism ; Time Factors

OBJECTIVE: To explore the effects of electroacupuncture (EA) on skeletal muscle and blood glucose in rats with diabetic amyotrophy. METHODS: Among 40 SD rats, 10 rats were randomly selected into the control group and received no treatment. The remaining 30 rats were treated with intraperitoneal injection of streptozotocin (STZ, 60 mg/kg) to establish diabetes mellitus (DM) model, and then the rats were treated with vascular ligation at right posterior limb to establish amyotrophy model. The rats with diabetic amyotrophy were randomly divided into a model group and an EA group, 10 rats in each group (10 rats were excluded due to unsuccessful model establishment and death). The rats in the EA group was treated with EA at right-side "Yishu (EX-B 3)" "Shenshu (BL 23)" "Zusanli (ST 36)" and "Sanyinjiao (SP 6)", disperse-dense wave, 2 Hz/ 15 Hz, 20 minutes each time, once a day for 3 weeks. Before and after EA treatment, the blood sample was collected from inner canthus and the "glucose oxidase-peroxidase" method was used to detect fasting blood glucose level; ELISA method was used to detect insulin content. At the end of the treatment, HE staining method was used to observe the morphology of ischemic skeletal muscle in the right hindlimb; the real-time PCR method was used to detect the mRNA expression of muscle atrophy F-box (MAFbx), muscle ring finger-1 (MuRF1) and forkhead box O3a (FOXO3a) in the ischemic skeletal muscle tissue of right hindlimb. RESULTS: Before the treatment, the body mass in the model group and EA group was lower than that in the control group (<0.01); after the treatment, the body mass in the control group was increased, while the body mass in the model group and EA group was decreased (<0.01). Compared with the control group, the fasting blood glucose was significantly increased and insulin content was significantly decreased in the model group (<0.01); compared with the model group, the fasting blood glucose was significantly decreased and the insulin content was significantly increased in the EA group after treatment (<0.01). The muscle fibers of the model group were obviously broken, the number of the nuclei decreased, and the nuclei shrinked or even dissolved; the morphology of the muscle tissue of the EA group after intervention was improved compared with the model group. Compared with the control group, the cross-sectional area of ischemic skeletal muscle cells in the right hindlimb in the model group was decreased (<0.01); compared with the model group, the cross-sectional area of ischemic skeletal muscle cells in the right hindlimb was increased in EA group (<0.05). Compared with the control group, the levels of MAFbx, MuRF1 and FOXO3a mRNA in the right hindlimb ischemic skeletal muscle in the model group were increased significantly (<0.01, <0.05); compared with the model group, the levels of MAFbx, MuRF1 and FOXO3a mRNA in the EA group were decreased significantly (<0.05, <0.01). CONCLUSION EA may play a role in the treatment of diabetic amyotrophy by inducing FOXO3a to reduce the transcription of MAFbx and MuRF1.
Acupuncture Points ; Animals ; Blood Glucose ; Diabetes Mellitus, Experimental ; chemically induced ; therapy ; Diabetic Neuropathies ; therapy ; Electroacupuncture ; Muscle, Skeletal ; physiology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo establish a rat model of diabetic erectile dysfunction (ED) with streptozotocin (STZ) injection.

METHODSThirty male rats were randomized equally into 5 groups (control group and STZ 40 mg/kg, 60 mg/kg, 80 mg/kg, and 100 mg/kg groups). All the rats were examined at 4 days and 1, 2, and 3 weeks after STZ injection for fasting blood glucose, erectile frequency induced by apomorpHine (APO) and body weight changes.

RESULTSSignificant difference occurred in the fasting food glucose among the groups at different time points (P=0.001), and also in APO-induced erectile frequency, fasting blood glucose and body weight between the groups with STZ injection at different doses (P<0.001, P=0.045 and P<0.001, respectively). No significant difference was found in induced erectile frequency and body weight between different time points (P=0.306 and P=0.628).

CONCLUSIONThe optimal dose of STZ for establishing diabetic ED model is 60 mg/kg, and two weeks after the injection can be the optimal time for evaluating model establishment by means of APO-induced penis erection.

Animals ; Apomorphine ; Diabetes Mellitus, Experimental ; chemically induced ; complications ; Disease Models, Animal ; Erectile Dysfunction ; etiology ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Streptozocin

OBJECTIVETo explore the dynamic changes of blood sugar and body's signs in streptozotocin diabetic animal models.

METHODSRat and mouse diabetic models were established by a single intraperitoneal (ip) injection and 5-day successive ip injections of streptozotocin respectively. Blood sugar levels were measured. The food consumption index (consumption of food/body weight) and the water consumption index (consumption of water/body weight) were calculated.

RESULTSSixty five point zero percent male rats received streptozotocin, 60 mg/kg ip, developed diabetes mellitus. The blood sugar remained in high level between the 15th day and the 25th day after injection, and it began to decline afterwards. By 5-day ip injections of streptozotocin, 40 mg/kg daily, 90.0% male mice developed diabetes mellitus. Dynamic changes of blood sugar of diabetic mouse were similar to those of rats, except that the blood sugar of mice did not decline as obvious as that of rats. The changes of water consumption index were in best fit with the changes of blood sugar in both models, with correlation index r>0.970.

CONCLUSIONThe blood sugar of diabetic animal model stayed in high level from the 15th day to the 25th day after the beginning of injection. And the period is suitable for observing effect of anti-diabetic drugs. The water consumption index can reflect the blood sugar levels of diabetes animals.

Animals ; Blood Glucose ; analysis ; Body Weight ; physiology ; Diabetes Mellitus, Experimental ; blood ; chemically induced ; physiopathology ; Disease Models, Animal ; Drinking ; physiology ; Eating ; physiology ; Male ; Mice ; Rats ; Rats, Wistar ; Streptozocin

OBJECTIVES: To investigate the effects of saffron aqueous extract (SE) on blood glucose, lipid and pancreatic tissue in streptozocin-induced diabetes mice. METHODS: Diabetes mellitus mice were established by intraperitoneal injection of streptozocin (60 mg/kg) for two consecutive days. The 30 well-established diabetes mice were randomly divided into three groups(=10):diabetic mellitus (DM) group, SE treated (SE) group and positive control (metformin hydrochloride, MH) group. Another ten normal mice were selected as normal control (NC) group. The mice in SE and MH groups were intragastrically administered with SE 100 mg/kg or MH 100 mg/kg once a day for 6 weeks, mice in DM and NC were given normal saline. The amount of food-intake, water consumption and body weight were measured weekly, the changes of the indicators including fasting blood glucose (FBG), oral glucose-tolerance test (OGTT), glycated serum protein (GSP), insulin (INS) and blood lipid were determined after 6 weeks of continuous administration. The pathologic changes in the pancreas tissues were detected by HE staining. RESULTS: Compared with the normal control group, the amount of food-intake, water consumption, area under the curve, FBG, GSP, and total cholesterol (TC) were significantly increased, while fasting weight, INS and high density lipoprotein cholesterol (HDL-c) were dramatically decreased in DM group. Compared with DM group, the water consumption, FBG, area under the curve and TC in SE group were starkly declined with a notable elevation of HDL-c and INS. In addition, the biopsy from DM mice showed the structure of pancreas islet was destroyed and reduced, and vascular proliferation with irregular shape. The damaged pancreas was obviously repaired by giving SE. CONCLUSIONS The saffron aqueous extract had efficacy on blood glucose and blood lipids reduction, improvement on damaged pancreas in streptozocininduced diabetic mice, which suggested that saffron could be used for the treatment in diabetes.
Animals ; Blood Glucose ; Crocus ; chemistry ; Diabetes Mellitus, Experimental ; chemically induced ; drug therapy ; Hypoglycemic Agents ; pharmacology ; Insulin ; blood ; Mice ; Plant Extracts ; pharmacology ; Random Allocation ; Streptozocin