The role of rosiglitazone treatment in the modulation of islet hormones and hormone-like peptides: a combined in situ hybridization and immunohistochemical study.
Rosiglitazone, peroxisome proliferator-activated receptor-gamma agonist, is an insulin sensitizing agent in peripheral tissues. This study investigated islet hormones and hormone-like peptides expression patterns in rosiglitazone treated streptozotocin (STZ)-diabetic rats by using immunohistochemistry and in situ hybridization methods. Animals were divided into four groups. I. Group: Intact control rats. II. Group: Rosiglitazone-treated controls. III. Group: STZ-diabetic rats. IV. Group: Rosiglitazone-treated diabetic animals. Rosiglitazone was given for 7 days at a dose of 20 mg/kg body weight. In the STZ-diabetic group, there were significant differences in islet hormones and hormone like peptides cell numbers compared to rosiglitazone control group and intact control group. There were significant differences in cocaine- and amphetamine-regulated transcript (CART) and pancreatic polypeptide (PP) cell numbers between rosiglitazone control group and rosiglitazone + STZ-diabetic group. We detected a significant decrease in glucagon mRNA signals in rosiglitazone-treated control group compared to intact controls. We found a statistically significant difference in islet amyloid polypeptide (IAPP) mRNA signals between the STZ-diabetic group and the rosiglitazone + STZ-diabetic group. Besides, we also demonstrated co-localization of peptides by using double and triple histochemistry. In conclusion, our results show that short-term rosiglitazone treatment had a preservative effect to some extent on the expression of islet hormones and hormone-like peptides to maintain the islet function.
Yildirim
Sukriye
S
Department of Biology of Cell Nucleus, Institute of Molecular Genetics AS CR, v.v.i. Videnska 1083, 142 20 Prague 4, Czech Republic. yildirim@img.cas.cz
Bolkent
Sema
S
Sundler
Frank
F
D000818:Animals; D003921:Diabetes Mellitus, Experimental; D006728:Hormones / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D047495:PPAR gamma / Q000819:agonists*; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D000077154:Rosiglitazone; D045162:Thiazolidinediones / Q000494:pharmacology*
D006728:Hormones; D007004:Hypoglycemic Agents; D047495:PPAR gamma; D010455:Peptides; D045162:Thiazolidinediones; D000077154:Rosiglitazone