| 1. |
- Marsell, Richard, et al.
(författare)
-
Gene expression analysis of kidneys from transgenic mice expressing fibroblast growth factor-23.
- 2008
-
Ingår i: Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. - : Oxford University Press (OUP). - 1460-2385 .- 0931-0509. ; 23:3, s. 827-33
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Fibroblast growth factor-23 (FGF23), a circulating protein produced in bone, causes decreased renal inorganic phosphate (Pi) reabsorption by reducing the expression of the sodium phosphate cotransporter type 2a (Npt2a). We have previously generated transgenic mice expressing human wild-type (WT) FGF23 under the control of the alpha1 (I) collagen promoter. METHODS: In this study, we performed a large-scale gene expression study of kidneys from FGF23 transgenic mice and WT littermates. Microarray expression data of key transcripts were verified by real-time RT-PCR analysis. RESULTS: Several genes that play a role in Pi regulation revealed decreased expression levels in the transgenic mice, such as Npt2a and Pdzk1, a scaffolding protein known to interact with Npt2a. Importantly, Klotho, a suggested FGF23 receptor cofactor, was the most significantly decreased transcript and alpha2-Na(+)/K(+)-ATPase (Atp1a2), a gene isoform of alpha1-Na(+)/K(+)-ATPase (Atp1a1) which has recently been shown to interact with Klotho and regulate calcium metabolism, was the most increased transcript. In contrast, other genes proposed to regulate Pi levels, such as secreted frizzled-related protein-4 (sFrp4) and Na(+)/H(+) exchanger regulatory factor-1 (Nherf1) revealed no changes. CONCLUSIONS: FGF23 transgenic mice display differentially expressed transcript levels of several genes essential in renal Pi regulation. These findings may lead to further understanding of how FGF23 mediates its actions on renal Pi regulation.
|
|
| 2. |
- Swanson, Charlotte, 1975, et al.
(författare)
-
The UDP Glucuronosyltransferase 2B15 D85Y and 2B17 Deletion Polymorphisms Predict the Glucuronidation Pattern of Androgens and Fat Mass in Men.
- 2007
-
Ingår i: Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:12, s. 4878-82
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Previous in vitro studies have demonstrated that the UDP glucuronosyltransferase (UGT) 2B15 and UGT2B17 glucuronidate androgens and their metabolites. Objective: To determine in vivo if the UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms predict androgen glucuronidation and body composition. Participants: Two population-based cohorts including young adult (n=1068, age=18.9 years) and elderly (n=1001, age=75.3 years) men. Main Outcome Measures: Serum and urine levels of testosterone (T) and dihydrotestosterone (DHT) measured by GC-MS and serum levels of the major glucuronidated androgen metabolites androstane-3alpha,17beta-diol(androstanediol)-3glucuronide, androstanediol-17glucuronide and androsterone-glucuronide measured by LC-MS/MS. Body composition measured by DXA. Results: Both the UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms were associated with serum levels of androstanediol-17glucuronide (p<0.001) but not with levels of androstanediol-3glucuronide or androsterone-glucuronide in both cohorts. Glucuronidation of T and DHT was associated with the UGT2B17 deletion but not with the UGT2B15 D(85)Y polymorphism, suggested by strong associations between the deletion polymorphism and urine levels of these two hormones. Both polymorphisms were associated with several different measures of fat mass (p<0.01). The UGT2B17 deletion polymorphism was associated with insulin sensitivity (p<0.05) as indicated by the HOMA index. Conclusions: The UGT2B15 D(85)Y and the UGT2B17 deletion polymorphisms are both predictors of the glucuronidation pattern of androgens/androgen metabolites. Our findings indicate that UGT2B17 is involved in 17 glucuronidation of mainly T but also of DHT and androstanediol and that UGT2B15 is involved in the 17 glucuronidation of androstanediol. Furthermore, these two polymorphisms are predictors of fat mass in men.
|
|
