蜂胶对糖尿病大鼠血糖的影响

将复制糖尿病模型的 72只SD大鼠随机分为模型组 ,蜂胶水提液低剂量组、高剂量组 ,蜂胶醇提液低剂量组、高剂量组和阳性对照组 (拜糖苹 ) ,另取 12只为正常组。除正常组和模型组外 ,各组分别给予不同的试验药物。给药过程中 ,每周取血一次 ,测空腹血糖 ,给药 7周后 ,取血测定空腹血糖和果糖胺。试验结果表明 ,蜂胶水提液和醇提液均能控制糖尿病大鼠空腹血糖的升高 ,并且随着时间的延长效果越来越明显。     

Study on relationship between expression of PKCα in glomeruli and development of nephropathy in diabetic rats

AIM:To observe the dynamic changes of expression of PKCα, TGF-β₁ and α-SMA in glomeruli of diabetic rats induced by the alloxon and to invesitigate their roles in the diabetic nephropathy(DN).METHODS:Rats were randomly divided into four groups: normal control group (group A), diabetic group of one week (group B), diabetic group of one month (group C), diabetic group of two months (group D). Immunohistochemistry and Western blotting were used to detect the expression of PKCα, TGF-β₁ and α-SMA in renal tissue of all groups. Blood glucose, triglycerides, cholesterol, creatinine and urine protein were analysed by chemical methods. The morphological changes of renal tissue were checked through microscopy.RESULTS:The expression of PKCα and TGF-β₁ in renal tissue of diabetic groups were increased comparing with those of nomal control group(P<0.05). The mesangial cells expressed α-SMA in two months group. Chronologically the expression of PKCα, TGF-β₁ and α-SMA were positively correlative with each other and the impairment of kidney was also observed.CONCLUSIONS: During the DN process the expression of PKCα increased. PKCα raised GFR and the permeability of glomerular filtration membrane which enhanced urinary albumin excretion. PKCα also increased expression of TGF-β and therefore to induce the expression of α-SMA. The appearance of α-SMA was a marker of the phenotypic transform of renal cells.     

Gene expression of 5α-reductase (type 2) in reproductive gland of pubertal diabetic rats

AIM: To study the molecular mechanism of reproduction dysfunction in pubertal diabetic rat, the level of 5α-reductase (type 2) mRNA in testis, epididymis and prostate in diabetic rat was detected. METHODS: The gene expression of 5α-reductase (type 2) was detected by Northern blot. RESULTS: In the caput of the epididymis, the expression of 5α-reductase (type 2) mRNA of D and ID groups was less than that of C group. CONCLUSION: The decreased expression of 5α-reductase (type 2) results in the decreased production of dihydrotestosterone, which influences the development and function of reproduction system in pubertal rats.     

The role of resistin in obesity and diabetes

Increased evidences indicate that resistin is a new hormone secreted from adipose tissue, it is reported to be an important signal molecule linking between obesity, insulin resistance and type 2 diabetes. Many factors can affect the gene expression of resistin. However, the detailed function of resistin still remains mysterious and much work needs to be undertaken.     

Ultrastructural impairment of islet microvascular endothelial cells in STZ-induced type 1 diabetic mice

AIM: To investigate the ultrastructural changes of islet microvascular endothelial cells in STZ-induced type 1 diabetic mice. METHODS: BALB/c mice were randomly divided into diabetic group and control group. The expression of insulin and platelet-endothelial cell adhesion molecule-1 (CD31) in islet microvessels was detected by immunohistochemical staining. The ultrastructural changes of islet β cells and islet microvessels were observed under transmission electron microscope. RESULTS: Compared with control group, the number of islet β cells, ratio of β cells/α cells, average number of secretory granules in β cells and insulin expression area per islet in diabetic group were significantly decreased (P<0.01). Besides, diabetic group had fewer microvessels with lower expression of CD31 (P<0.01). Mitochondria in islet microvascular endothelial cells and pericytes in diabetic group were swelling. The basement membrane of islet microvessels became thicker in diabetic group (P<0.01). CONCLUSION: Islet microvascular endothelial cells were impaired in type 1 diabetic mice.     

Relationship between anti-insulin antibody production and severe insulin resistance in a diabetic cat

A 5-year-old castrated male domestic shorthair cat was diagnosed with diabetic ketoacidosis and severe insulin resistance. Although the conventional treatment for diabetic ketoacidosis was provided, the cat required frequent hospitalization because of severe dehydration and repeated diabetic ketoacidosis. We detected anti-insulin antibodies for human in this cat. Serum insulin-binding IgG levels were markedly elevated compared with those in healthy cats and other diabetic cats. We initiated prednisolone to suppress the effects of anti-insulin antibodies. After initiation of prednisolone, the cat was gradually recovered with increasing activity and appetite. Furthermore, satisfactory glycemic control was achieved with combined subcutaneous injection of insulin detemir and insulin degludec.