Improvement of the function of islet beta and alpha cells by intervention against glucotoxicity : experiment with rats

OBJECTIVE: To investigate the effects of intervention against glucotoxicity on improvement of the function and pathological changes of islet beta and alpha cells.

METHODS: Thirty-six male Sprague Dawley rats were randomly divided into four equal groups: normal control (NC) group, fed with standard chow, high-fat (HF) group, fed with extra high-fat chow; diabetes mellitus (DM) control group, fed with high-fat chow for 8 weeks followed by 30 mg/kg streptozotocin injection to establish DM models; and insulin (INS) group, treated with subcutaneous injection of long-acting insulin (glargine, 0.5 U x kg(-1) x d(-1)) for 4 weeks after the establishment of DM models. 48 h, 2 weeks, and 4 weeks after the STZ injection to the 2 DM groups oral glucose tolerance test (OGTT) was performed to all rats. Peripheral blood samples were collected from the caudal vein. Serum insulin level was assayed by radioimmunoassay. Total serum cholesterol (TC) and triglyceride (TG) were measured by enzyme-colorimetric method. By the end of experiment the rats were killed with their pancreases taken out. Immunohistochemistry was used to observe the morphological changes of the islet beta and alpha cells. Beta cell and alpha cell masses were calculated by the proportions of positive area in the islet. Proinsulin mRNA level was detected by RT-PCR. Insulin protein content in islets was detected by Western blotting.

RESULTS: Four weeks after the insulin intervention against glucotoxicity, the fasting blood glucose and blood glucose 2 h after sugar-taking of the INS group were both significantly lower than those of the DM group (both P < 0.01). The relative beta cell mass of the INS group was 0.38 +/- 0.08, significantly bigger, 2.45 times, that of the DM group (0.11 +/- 0.05, P < 0.01). The relative alpha cells mass in islets of the INS group was 0.16 +/- 0.04, significantly lower, by 43%, than that of the DM group (0.28 +/- 0.15, P < 0.01). The insulin contents in beta cells of the INS group was 0.58 +/- 0.03, significantly higher, by 70.6%, than that of the DM group (0.34 +/- 0.14, P < 0.01). The proinsulin mRNA level of the INS group was 1.52 +/- 0.14, significantly higher, by 20.6%, than that of the DM group.

CONCLUSION: The morphology of islet beta, alpha cells in diabetic rats was improved by four weeks of Intervention against glucotoxicity improves the pathology of islet beta and alpha cells in diabetic and insulin synthesis.

Medienart:

Artikel

Erscheinungsjahr:

2008

Erschienen:

2008

Enthalten in:

Zur Gesamtaufnahme - volume:88

Enthalten in:

Zhonghua yi xue za zhi - 88(2008), 6 vom: 05. Feb., Seite 374-7

Sprache:

Chinesisch

Beteiligte Personen:

He, Qing-Hua [VerfasserIn]
Zhou, Ying-Sheng [VerfasserIn]
Wang, Zheng [VerfasserIn]
Wang, Shu [VerfasserIn]
Mou, Zhong-Qing [VerfasserIn]
Li, Jian [VerfasserIn]
Chi, Jia-Min [VerfasserIn]

Themen:

9035-68-1
97C5T2UQ7J
Blood Glucose
Cholesterol
Dietary Fats
English Abstract
Glucose
IY9XDZ35W2
Insulin
Journal Article
Proinsulin
Research Support, Non-U.S. Gov't
Triglycerides

Anmerkungen:

Date Completed 22.12.2008

Date Revised 21.11.2013

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM180477102