PPAR­Î³ agonist rosiglitazone protects rat peritoneal mesothelial cells against peritoneal dialysis solution­induced damage.

Long-term peritoneal dialysis (PD) leads to ultrafiltration failure (UFF). Peritoneal mesothelial cells, which form the innermost monolayer of the peritoneal cavity, have been shown to regulate various responses, including inflammation, in UFF. The present study was designed to investigate the effect of the peroxisome proliferator­activated receptor­Î³ (PPAR­Î³) agonist, rosiglitazone, on peritoneal dialysis solution (PDS)­induced injuries in rat peritoneal mesothelial cells (RPMCs). RPMCs were cultured for different durations and with different concentrations of PDS. The gene expression levels of aquaporin­1 (AQP­1) and zonula occluden­1 (ZO­1) were determined using reverse transcription­quantitative polymerase chain reaction analysis. The protein levels of AQP­1, ZO­1 and PPAR­Î³ were measured using western blot analysis. Interleukin (IL)­6 and IL­8 were detected using ELISA. The RPMCs were damaged by stimulation with 4.25% PDS for 72 h. The expression levels of AQP­1 and ZO­1 were increased, and the secretion of IL­6 and IL­8 were decreased by rosiglitazone. The use of the PPAR­Î³ inhibitor, GW­9662, completely prevented the effects of rosiglitazone. These results indicated that PDS exposure stimulated an inflammatory response in the RPMCs. The PPAR­Î³ activator, rosiglitazone, appeared to relieve the injury by inhibiting inflammation, and regulating the expression of AQP­1 and ZO­1, however further investigations are required to elucidate the potential underlying mechanism.

Involvement of peroxisome proliferator activated receptor-γ in the anti-inflammatory effects of atorvastatin in oxygen-glucose deprivation/reperfusion-stimulated RAW264.7 murine macrophages.

Ischemia­reperfusion (I/R) injury is important in the pathogenesis and/or progression of various diseases, including stroke, cardiovascular disease and acute renal injury. Increasing evidence indicates that atorvastatin exerts protective effects in I/R injury­associated diseases; however, the underlying mechanisms remain to be fully elucidated. In the present study, oxygen­glucose deprivation (OGD)/reperfusion­stimulated. RAW264.7 murine macrophages served as a model of I/R injury. The knockdown of peroxisome proliferator activated receptor­Î³ (PPARγ) expression in these cells increased OGD/reperfusion­induced expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor­α (TNF­α) and interferon­Î³ (IFN­Î³), and enhanced OGD/reperfusion­induced downregulation of the expression of cluster of differentiation (CD) 206, at the mRNA and protein levels. Conversely, overexpression of PPARγ significantly attenuated OGD/reperfusion­induced alterations in the expression of iNOS, TNF­α, IFN­Î³ and CD206 at the mRNA and protein levels. Notably, atorvastatin inhibited OGD/reperfusion­induced iNOS expression and reversed OGD/reperfusion­induced downregulation of the expression of CD206 and PPARγ at the mRNA and protein levels. The results of the present study indicate that atorvastatin exhibits significant anti­inflammatory effects in OGD/reperfusion­stimulated RAW264.7 cells, possibly via PPARγ regulation. The findings of the present study may reveal a novel mechanism underlying the protective effects of atorvastatin in I/R injury­associated diseases.

Frequencies of apolipoprotein E alleles in depressed patients undergoing hemodialysis--a case-control study.

OBJECTIVE: To explore the relation between the frequencies of apolipoprotein E (ApoE) alleles and the occurrence of depression in patients undergoing hemodialysis in a Chinese population. METHODS: We examined the ApoE alleles in a sample of 288 subjects: 72 patients with depression under hemodialysis, 74 patients without depression under hemodialysis, 75 patients with depression under nondialytic treatment and 67 patients without depression under nondialytic treatment. The depression state was assessed using the Center for Epidemiological Studies Depression (CES-D) scale. Associations between the occurrence of depression and the frequencies of ApoE alleles were examined using multinomial logistic regression models with adjustment of relevant covariates. Information about sociodemographics, clinical data, vascular risk factors and cognitive function was also collected and evaluated. RESULTS: The frequencies of ApoE-ɛ2 were significantly different between depressed and non-depressed patients irrespective of dialysis (p < 0.05), but no significant difference was found in the frequencies of ApoE-ɛ4 (p > 0.05). Serum ApoE levels were significantly different between depressed and non-depressed patients in the whole sample (p < 0.05). Multinomial logistic regression models showed significant association between the frequency of ApoE-ɛ2 and the occurrence of depression in the Chinese population after control of relevant covariates, including age, sex, educational level, history of smoking and drinking, vascular risk factors and cognitive function. CONCLUSIONS: No association between the frequency of ApoE-ɛ4 and the occurrence of depression was found in patients undergoing hemodialysis. Further research is needed to find out if ApoE-ɛ2 acts as a protective factor in Chinese dialysis population since it might decrease the prevalence of depression and delay the onset age.