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High-fat diet (HFD) can cause obesity, inducing dysregulation of the visceral adipose tissue (VAT). This study aimed to explore potential biological pathways and hub genes involved in obese VAT, and for that, bioinformatic analysis of multiple datasets was performed. The expression profiles (GSE30247, GSE167311 and GSE79434) were downloaded from Gene Expression Omnibus. Overlapping differentially expressed genes (ODEGs) between normal diet and HFD groups in GSE30247 and GSE167311 were selected to run protein–protein interaction network, GO and KEGG analysis. The hub genes in ODEGs were screened by Cytoscape software and further verified in GSE79434 and obese mouse model. A total of 747 ODEGs (599 up-regulated and 148 down-regulated) were screened, and the GO and KEGG analysis showed that the up-regulated ODEGs were significantly enriched in inflammatory response and extracellular matrix receptor interaction pathways. On the other hand, the down-regulated ODEGs were involved in metabolic pathways; however, there were no significant KEGG pathways. Furthermore, six hub genes, Mki67, Rac2, Itgb2, Emr1, Tyrobp and Csf1r were acquired. These pathways and genes were verified in GSE79434 and VAT of obese mice. This study revealed that HFD induced VAT expansion, inflammation and fibrosis, and the hub genes could be used as therapeutic biomarkers in obesity. [ABSTRACT FROM AUTHOR]

Abstract Background Recent studies revealed that erythropoietin (EPO) has tissue-protective effects in the heart by increasing vascular endothelial growth factor (VEGF) expression and attenuating myocardial fibrosis in ischemia models. In this study, we investigated the effect of EPO on ventricular remodeling and blood vessel growth in diabetic rats. Methods Male SD rats were randomly divided into 3 groups: control rats, streptozotocin (STZ)-induced diabetic rats, and diabetic rats treated with 1000 U/kg EPO by subcutaneous injection once per week. Twelve weeks later, echocardiography was conducted, and blood samples were collected for counting of peripheral blood endothelial progenitor cells (EPCs). Myocardial tissues were collected, quantitative real-time PCR (RT-PCR) was used to detect the mRNA expression of VEGF and EPO-receptor (EPOR), and Western blotting was used to detect the protein expression of VEGF and EPOR. VEGF, EPOR, transforming growth factor beta (TGF-β), and CD31 levels in the myocardium were determined by immunohistochemistry. To detect cardiac hypertrophy, immunohistochemistry of collagen type I, collagen type III, and Picrosirius Red staining were performed, and cardiomyocyte cross-sectional area was measured. Results After 12 weeks STZ injection, blood glucose increased significantly and remained consistently elevated. EPO treatment significantly improved cardiac contractility and reduced diastolic dysfunction. Rats receiving the EPO injection showed a significant increase in circulating EPCs (27.85 ± 3.43%, P Conclusions Treatment with EPO protects cardiac tissue in diabetic animals by increasing VEGF and EPOR expression levels, leading to improved revascularization and the inhibition of cardiac fibrosis.

An inverse relationship exists between kallistatin levels and salt-induced oxidative stress in Dahl-salt sensitive rats. We further investigated the role of kallistatin in inhibiting inflammation and fibrosis through antioxidative stress in Dahl-salt sensitive rats and cultured renal cells. High-salt intake in Dahl-salt sensitive rats induced elevation of thiobarbituric acid reactive substances (an indicator of lipid peroxidation), malondialdehyde levels, reduced nicotinamide-adenine dinucleotide phosphate oxidase activity, and superoxide formation, whereas kallistatin gene delivery significantly reduced these oxidative stress parameters. Kallistatin treatment improved renal function and reduced kidney damage as evidenced by diminished proteinuria and serum urea nitrogen levels, glomerular sclerosis, tubular damage, and protein cast formation. Kallistatin significantly decreased interstitial monocyte-macrophage infiltration and the expression of tumor necrosis factor-alpha, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1. Kallistain also reduced collagen fraction volume and the deposition and expression of collagen types I and III. Renal protection by kallistatin was associated with increased NO levels and endothelial NO synthase expression and decreased p38 mitogen-activated protein kinase, extracellular signal-regulated kinase phosphorylation, and transforming growth factor-beta1 expression. Moreover, kallistatin attenuated tumor necrosis factor-alpha-induced intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression via inhibition of reactive oxygen species formation and p38 mitogen-activated protein kinase and nuclear factor-kappaB activation in cultured proximal tubular cells. Kallistatin inhibited fibronectin and collagen expression by suppressing angiotensin II-induced reactive oxygen species generation and transforming growth factor-beta1 expression in cultured mesangial cells. These combined findings reveal that kallistatin is a novel antioxidant, which prevents salt-induced kidney injury, inflammation, and fibrosis by inhibiting reactive oxygen species-induced proinflammatory cytokine and transforming growth factor-beta1 expression. [ABSTRACT FROM AUTHOR]

Abstract: Objective: We assessed the role of glycogen synthase kinase-3β (GSK-3β) and kinin B2 receptor in mediating tissue kallikrein''s protective effects against cardiac hypertrophy. Methods: We investigated the effect and mechanisms of tissue kallikrein using hypertrophic animal models of rats as well as mice deficient in kinin B1 or B2 receptor after aortic constriction (AC). Results: Intramyocardial delivery of adenovirus containing the human tissue kallikrein gene resulted in expression of recombinant kallikrein in rat myocardium. Kallikrein gene delivery improved cardiac function and reduced heart weight/body weight ratio and cardiomyocyte size without affecting mean arterial pressure 28 days after AC. Icatibant and adenovirus carrying a catalytically inactive GSK-3β mutant (Ad.GSK-3β-KM) abolished kallikrein''s effects. Kallikrein treatment increased cardiac nitric oxide (NO) levels and reduced NAD(P)H oxidase activity and superoxide production. Furthermore, kallikrein reduced the phosphorylation of apoptosis signal-regulating kinase1, mitogen-activated protein kinases (MAPKs), Akt, GSK-3β, and cAMP-response element binding (CREB) protein, and decreased nuclear factor-κB (NF-κB) activation in the myocardium. Ad.GSK-3β-KM abrogated kallikrein''s actions on GSK-3β and CREB phosphorylation and NF-κB activation, whereas icatibant blocked all kallikrein''s effects. The protective role of kinin B2 receptor in cardiac hypertrophy was further confirmed in kinin receptor knockout mice as heart weight/body weight ratio and cardiomyocyte size increased significantly in kinin B2 receptor knockout mice after AC compared to wild type and B1 receptor knockout mice. Conclusions: These findings indicate that tissue kallikrein, through kinin B2 receptor and GSK-3β signaling, protects against pressure overload-induced cardiomyocyte hypertrophy by increased NO formation and oxidative stress-induced Akt-GSK-3β-mediated signaling events, MAPK and NF-κB activation. [Copyright &y& Elsevier]

Objective: To explore the association between the gene mutation of transcription factor Nkx2.5 and Chinese patients with congenital heart disease (CHD)., Methods: Polymerase chain reaction (PCR) and DNA sequencing were used to check 99 CHD patients and 90 normal control subjects from the Zhong Da Hospital of Southeast University. After amplifying the exons 1 of the Nkx2.5 gene by PCR, we purified the PCR products and conducted the sequencing reaction, analyzed the mutation screening of the exon 1 of the Nkx2.5, investigated whether or not the Nkx2.5 is related with the CHD in Chinese population., Results: A mutation (A239G) in the exon 1 of the Nkx2.5 was identified in 3 of 90 normal control subjects and 12 of 99 CHD patients, including 3 of 24 with VSD, 7 of 35 with ASD, 1 of 13 with PS and 1 of 21 with PDA., Conclusion: There are some associations between the Nkx2.5 gene mutation and occurrence of congenital heart disease in Chinese people.

Aim: To investigate the cyclooxygenase-2 (COX-2) expression level in human HepG2, Bel-7402 and SMMC-7721 hepatoma cell lines and the molecular mechanism of COX-2 selective inhibitor celecoxib-induced cell growth inhibition and cell apoptosis., Methods: Hepatoma cells were cultured and treated with celecoxib. Cell in situ hybridization (ISH) and immunocytochemistry were used to detect COX-2 mRNA and protein expression. Proliferating cell nuclear antigen and phosphorylated Akt were also detected by immunocytochemistry assay. Cell growth rates were assessed by 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium (MTT) bromide colorimetric assay. Celecoxib-induced cell apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and flow cytometry (FCM). The phosphorylated Akt and activated fragments of caspase-9, caspase-3 were examined by Western blotting analysis., Results: Increased COX-2 mRNA and protein expression were detected in all three hepatoma cell lines. Celecoxib could significantly inhibit cell growth and the inhibitory effect was in a dose- and time-dependent manner evidenced by MTT assays and morphological changes. The apoptotic index measured by TUNEL increased correspondingly with the increased concentration of celecoxib and the reaction time. With 50 micromol/L celecoxib treatment for 24 h, the apoptotic index of HepG2, BEL-7402 and SMMC-7721 cells was 25.01+/-3.08%, 26.40+/-3.05%, and 30.60+/-2.89%, respectively. Western blotting analysis showed remarkable activation of caspase-9, caspase-3 and dephosphorylation of Akt (Thr(308)). Immunocytochemistry also showed the reduction of PCNA expression and phosphorylation Akt (Thr(308)) after treatment with celecoxib., Conclusion: COX-2 mRNA and protein overexpression in HepG2, Bel-7402 and SMMC-7721 cell lines correlate with the increased cell growth rate. Celecoxib can inhibit proliferation and induce apoptosis of hepatoma cell strains in a dose- and time-dependent manner.