OBJECTIVETo breed neual stem cell-specific peroxisome proliferator-activated receptor γ (PPARγ) knockout mice.

METHODSTwo transgenic mouse models, namely B6.PPARγloxp/loxp and B6.Nestin-Cre were interbred, and the first- generation offsprings were backcrossed with B6.PPARγloxp/loxp to obtain the second-generation mice. Genomic DNA was extracted from the second-generation mice for PCR to amplify the loxp and Cre gene fragments followed by agarose gel electrophoresis to verify their sizes. The mice with the PPARγloxp/loxp.Nestin-Cre (KO) genotype were selected as the neural stem cell-specific knockout PPARγ mice, with B6.PPARγloxp/loxp (loxp) mice as the control. Tissue samples were collected from specific regions of the mouse brain and peripheral tissue for detecting the expression of PPARγ mRNA using RT-PCR and real-time quantitative PCR.

RESULTS AND CONCLUSIONGenotyping results showed PPARγloxp and Cre bands in the knockout mice, which showed obviously decreased mRNA expression of PPARγ, suggesting successful establishment of neural stem cell-specific PPARγ knockout mice. The two transgenic mice we used were fertile, and their breeding pattern followed the laws of Mendelian inheritance.

Animals ; Genotype ; Mice ; Mice, Knockout ; Neural Stem Cells ; PPAR gamma ; genetics ; RNA, Messenger

OBJECTIVETo investigate the effect of peroxisome proliferator-activated receptors γ (PPARγ) on insulin receptor substrate-4 (IRS-4) gene expression in the brain.

METHODSPrimarily cultured cortical neurons from E17-18 Sprague Dawley rats, after 1 week of plating, were exposed to 10 µmol/L PPARγ agonist rosiglitazone for 0, 1, 4 or 24 h. Adult C57BL/6J mice or conditional brain PPARγ knock-out mice (B-PPARγ-KO, BKO) received an intraperitoneal injection of rosiglitazone in 10% DMSO at 12 mg/kg or injection of the same volume of saline containing 10% DMSO. The effect of rosiglitazone on the survival of the neurons was examined by MTT assay. The expression of IRS-4 mRNA was analyzed by real-time quantitative PCR.

RESULTSThe survival of the cortical neurons showed no significant difference between the agonist groups and the control group. The expression of IRS-4 mRNA was significantly up-regulated in the cortical tissues and neurons of the agonist groups compared with the control groups (P<0.05), but in BKO mice without treatment, IRS-4 mRNA expression was significantly down-regulated (P<0.05).

CONCLUSIONPPARγ can enhance the expression of IRS-4 mRNA in the brain.

Animals ; Cell Survival ; drug effects ; Cells, Cultured ; Cerebral Cortex ; cytology ; metabolism ; Female ; Gene Transfer Techniques ; Insulin Receptor Substrate Proteins ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Neurons ; cytology ; metabolism ; PPAR gamma ; agonists ; genetics ; metabolism ; Pregnancy ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Thiazolidinediones ; pharmacology ; Up-Regulation