Inhibition of Aldose Reductase Activates Hepatic Peroxisome Proliferator-Activated Receptor-α and Ameliorates Hepatosteatosis in Diabetic db/db Mice

We previously demonstrated in streptozotocin-induced diabetic mice that deficiency or inhibition of aldose reductase (AR) caused significant dephosphorylation of hepatic transcriptional factor PPARα, leading to its activation and significant reductions in serum lipid levels. Herein, we report that inhibition of AR by zopolrestat or by a short-hairpin RNA (shRNA) against AR caused a significant reduction in serum and hepatic triglycerides levels in 10-week old diabetic db/db mice. Meanwhile, hyperglycemia-induced phosphorylation of hepatic ERK1/2 and PPARα was significantly attenuated in db/db mice treated with zopolrestat or AR shRNA. Further, in comparison with the untreated db/db mice, the hepatic mRNA expression of Aco and ApoA5, two target genes for PPARα, was increased by 93% (P < 0.05) and 73% (P < 0.05) in zopolrestat-treated mice, respectively. Together, these data indicate that inhibition of AR might lead to significant amelioration in hyperglycemia-induced dyslipidemia and nonalcoholic fatty liver disease

Omega-3 fatty acids and genome-wide interaction analyses reveal DPP10-pulmonary function association

Rationale: Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have anti-inflammatory properties that could benefit adults with comprised pulmonary health. Objective: To investigate n-3 PUFA associations with spirometric measures of pulmonary function tests (PFTs) and determine underlying genetic susceptibility. Methods: Associations of n-3 PUFA biomarkers (a-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid [DPA], and docosahexaenoic acid [DHA]) were evaluated with PFTs (FEV1, FVC, and FEV1/FVC) in meta-analyses across seven cohorts from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium (N=16,134 of European or African ancestry). PFT-associated n-3 PUFAs were carried forward to genome-wide interaction analyses in the four largest cohorts (N=11,962) and replicated in one cohort (N=1,687). Cohort-specific results were combined using joint 2 degree-of-freedom (2df) meta-analyses of SNPassociations and their interactions with n-3PUFAs. Results: DPA and DHA were positively associated with FEV1 and FVC (P < 0.025), with evidence for effect modification by smoking and by sex. Genome-wide analyses identified a novel association of rs11693320-an intronic DPP10 SNP-with FVC when incorporating an interaction with DHA, and the finding was replicated (P-2df = 9.4 x 10(-9) across discovery and replication cohorts). The rs11693320-A allele (frequency, similar to 80%) was associated with lower FVC (P-SNP = 2.1 x 10(-9); beta(SNP) = 2161.0 ml), and the association was attenuated by higher DHA levels (P-SNPxDHA interaction = 2.1x10(-7); beta(SNPxDHA interaction) = 36.2 ml). Conclusions: We corroborated beneficial effects of n-3 PUFAs on pulmonary function. By modeling genome-wide n-3 PUFA interactions, we identified a novel DPP10 SNP association with FVC that was not detectable in much larger studies ignoring this interaction

Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (SD 29) nmol/l for EA and 49 (SD 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1.1 ml in EA (95 % CI 0.9, 1.3; P< 0.0001) and 1.8 ml (95 % CI 1.1, 2.5; P< 0.0001) in AA (P-race (difference) = 0.06), and forced vital capacity (FVC) was higher by 1.3 ml in EA (95 % CI 1.0, 1.6; P <0.0001) and 1.5 ml (95 % CI 0.8, 2.3; P= 0.0001) in AA (P-race difference = 0.56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH) D, FVC was higher by 1.7 ml (95 % CI 1.1, 2.3) for current smokers and 1.7 ml (95 % CI 1.2, 2.1) for former smokers, compared with 0.8 ml (95 % CI 0.4, 1.2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations

Genome wide association study of apparent treatment resistant hypertension in the CHARGE consortium: the CHARGE pharmacogenetics working group

Background: Only a handful of genetic discovery efforts in apparent treatment-resistant hypertension (aTRH) have been described. Methods: We conducted a case–control genome-wide association study of aTRH among persons treated for hypertension, using data from 10 cohorts of European ancestry (EA) and 5 cohorts of African ancestry (AA). Cases were treated with 3 different antihypertensive medication classes and had blood pressure (BP) above goal (systolic BP ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg) or 4 or more medication classes regardless of BP control (nEA = 931, nAA = 228). Both a normotensive control group and a treatment-responsive control group were considered in separate analyses. Normotensive controls were untreated (nEA = 14,210, nAA = 2,480) and had systolic BP/diastolic BP &lt; 140/90 mm Hg. Treatment-responsive controls (nEA = 5,266, nAA = 1,817) had BP at goal (&lt;140/90 mm Hg), while treated with one antihypertensive medication class. Individual cohorts used logistic regression with adjustment for age, sex, study site, and principal components for ancestry to examine the association of single-nucleotide polymorphisms with case–control status. Inverse variance-weighted fixed-effects meta-analyses were carried out using METAL. Results: The known hypertension locus, CASZ1, was a top finding among EAs (P = 1.1 × 10−8) and in the race-combined analysis (P = 1.5 × 10−9) using the normotensive control group (rs12046278, odds ratio = 0.71 (95% confidence interval: 0.6–0.8)). Single-nucleotide polymorphisms in this locus were robustly replicated in the Million Veterans Program (MVP) study in consideration of a treatment-responsive control group. There were no statistically significant findings for the discovery analyses including treatment-responsive controls. Conclusion: This genomic discovery effort for aTRH identified CASZ1 as an aTRH risk locus

Inhibition of Aldose Reductase Activates Hepatic Peroxisome Proliferator-Activated Receptor-alpha and Ameliorates Hepatosteatosis in Diabetic db/db Mice

Natural Science Foundation of Fujian Province, China [2009J01180]; Science Planning Program of Fujian Province [2010J1008]; National Science Foundation of China [30970649]We previously demonstrated in streptozotocin-induced diabeticmice that deficiency or inhibition of aldose reductase (AR) caused significant dephosphorylation of hepatic transcriptional factor PPAR alpha, leading to its activation and significant reductions in serum lipid levels. Herein, we report that inhibition of AR by zopolrestat or by a short-hairpin RNA (shRNA) against AR caused a significant reduction in serum and hepatic triglycerides levels in 10-week old diabetic db/db mice. Meanwhile, hyperglycemia-induced phosphorylation of hepatic ERK1/2 and PPAR alpha was significantly attenuated in db/db mice treated with zopolrestat or AR shRNA. Further, in comparison with the untreated db/db mice, the hepatic mRNA expression of Aco and ApoA5, two target genes for PPAR alpha, was increased by 93% (P < 0.05) and 73% (P < 0.05) in zopolrestat-treated mice, respectively. Together, these data indicate that inhibition of AR might lead to significant amelioration in hyperglycemia-induced dyslipidemia and nonalcoholic fatty liver disease