Background: Glucocorticoids (GCs) are potent therapeutic agents frequently used for treatment of number of conditions, including hematologic, inflammatory, and allergic diseases. Both their therapeutic and adverse effects display significant interindividual variation, partially attributable to genetic factors. We have previously isolated a seven-gene region of rat chromosome 8 sensitizing to dexamethasone (DEX)-induced dyslipidemia and insulin resistance (IR) of skeletal muscle. Using two newly derived congenic strains, we aimed to investigate the effect of one of the prime candidates for this pharmacogenetic interaction, the Zbtb16 gene. Methods: Adult male rats of SHR-Lx.PD5PD-Zbtb16 (n = 9) and SHR-Lx.PD5SHR-Zbtb16 (n = 8) were fed standard diet (STD) and subsequently treated with DEX in drinking water (2.6 μg/ml) for 3 days. The morphometric and metabolic profiles of both strains including oral glucose tolerance test, triacylglycerols (TGs), free fatty acids, insulin, and C-reactive protein levels were assessed before and after the DEX treatment. Insulin sensitivity of skeletal muscle and visceral adipose tissue was determined by incorporation of radioactively labeled glucose. Results: The differential segment of SHR-Lx.PD5SHR-Zbtb16 rat strain spans 563 kb and contains six genes: Htr3a, Htr3b, Usp28, Zw10, Tmprss5, and part of Drd2. The SHR-Lx.PD5PD-Zbtb16 minimal congenic strain contains only Zbtb16 gene on SHR genomic background and its differential segment spans 254 kb. Total body weight was significantly increased in SHR-Lx.PD5PD-Zbtb16 strain compared with SHR-Lx.PD5SHR-Zbtb16 , however, no differences in the weights of adipose tissue depots were observed. While STD-fed rats of both strains did not show major differences in their metabolic profiles, after DEX treatment the SHR-Lx.PD5PD-Zbtb16 congenic strain showed increased levels of TGs, glucose, and blunted inhibition of lipolysis by insulin. Both basal and insulin-stimulated incorporation of radioactively labeled glucose into skeletal muscle glycogen were significantly reduced in SHR-Lx.PD5PD-Zbtb16 strain, but the insulin sensitivity of adipose tissue was comparable between the two strains. Conclusion: The metabolic disturbances including impaired glucose tolerance, dyslipidemia, and IR of skeletal muscle observed after DEX treatment in the congenic SHR-Lx.PD5PD-Zbtb16 reveal the Zbtb16 locus as a possible sensitizing factor for side effects of GC therapy.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: All-trans retinoic acid (ATRA, tretinoin) is a vitamin A derivative commonly used in the treatment of diverse conditions ranging from cancer to acne. In a fraction of predisposed individuals, the administration of ATRA is accompanied by variety of adverse metabolic effects, particularly by the induction of hyperlipidemia. We have previously derived a minimal congenic SHR.PD-(D8Rat42-D8Arb23)/Cub (SHR-Lx) strain sensitive to ATRA-induced increase of triacylglycerols and cholesterol under condition of high-sucrose diet. SHR-Lx differs only by 7 genes of polydactylous rat (PD/Cub) origin from its spontaneously hypertensive rat (SHR) progenitor strain. METHODS: Adult male rats of SHR and SHR-Lx strains were fed standard diet (STD) and experimental groups were subsequently treated with ATRA (15 mg/kg) via oral gavage for 16 days, while still on STD. We contrasted the metabolic profiles (including free fatty acids, triacylglycerols (TG) and cholesterol (C) in 20 lipoprotein fractions) between SHR and SHR-Lx under conditions of standard diet and standard diet + ATRA. We performed transcriptomic analysis of muscle tissue (m. soleus) in all groups using Affymetrix GeneChip Rat Gene 2.0 ST Arrays followed by Ingenuity Pathway Analysis and real-time PCR validation. RESULTS: In response to ATRA, SHR-Lx reacted with substantially greater rise in TG and C concentrations throughout the lipoprotein spectrum (two-way ANOVA strain * RA interaction significant for C content in chylomicrons (CM), VLDL and LDL as well as total, CM and HDL-TG). CONCLUSIONS: According to our modeling of metabolic and signalization pathways using differentially expressed genes we have identified a network with major nodes (including Sirt3, Il1b, Cpt1b and Pparg) likely to underlie the observed strain specific response to ATRA.
- MeSH
- dyslipidemie krev chemicky indukované genetika MeSH
- kosterní svaly metabolismus MeSH
- lipidy krev MeSH
- metabolismus lipidů MeSH
- potkani inbrední SHR MeSH
- transkriptom * MeSH
- tretinoin MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Ondansetron is an antagonist of 5-HT3 receptors mostly used as an antiemetic yet known to modulate metabolism and appetite. We tested the metabolic effects of ondansetron in newly derived congenic rat strain, carrying limited chromosome 8 regions of (PD) Brown Norway (BN) and polydactylous (PD) strain origins (including variant serotonin receptor Htr3b gene) within the genomic background of highly inbred model of metabolic syndrome, the spontaneously hypertensive rat (SHR). METHODS: Adult, standard diet-fed male rats of SHR and the congenic SHR.(PD/BN)8 strains received ondansetron (2mg/kg body weight/day) or vehicle (n=6/strain/treatment) via oral gavage for 14 days while we followed their metabolic and morphometric profiles including glucose tolerance and triacylgycerol and cholesterol concentrations in 20 lipoprotein fractions. RESULTS: We fine-mapped the chromosome 8 differential segment in the new SHR.(PD/BN)8 congenic strain: it comprises BN-derived region together with an adjacent 422kb stretch of PD origin. The SHR.(PD/BN)8 rats were heavier than SHR, the fasting glucose was significantly higher in ondansetron-treated congenic than in SHR (post-hoc Tukey's HSD p=0.02). Compared to SHR, ondansetron induced significantly more robust increases of cholesterol and triacylglycerol concentrations in total, chylomicron, VLDL and HDL particles in the SHR.(PD/BN)8 congenic strain. CONCLUSION: We established new congenic model with distinct pharmacogenetic profile related to metabolic effects of ondansetron, facilitating thus the search for responsible genetic variants within the limited genomic region demarcated by the differential segment.
- MeSH
- antagonisté serotoninových receptorů 5-HT3 farmakologie MeSH
- hypertenze farmakoterapie genetika metabolismus MeSH
- krysa rodu rattus MeSH
- lipidy krev MeSH
- metabolický syndrom farmakoterapie genetika metabolismus MeSH
- modely nemocí na zvířatech * MeSH
- ondansetron farmakologie MeSH
- polydaktylie genetika MeSH
- porucha glukózové tolerance farmakoterapie genetika metabolismus MeSH
- potkani inbrední BN MeSH
- potkani inbrední SHR * MeSH
- receptory serotoninové 5-HT3 genetika metabolismus MeSH
- savčí chromozomy MeSH
- zvířata kongenní MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
