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Background: Bladder transitional cell carcinoma greatly threatens human health all over the world. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows a strong apoptosis-inducing effect on a variety of cancer cells including bladder cancer. However, adenovirus-mediated TRAIL expression still showed cytotoxicity to normal cells mainly due to lack of tumor specificity. Methods: To solve the problem, we applied miRNA response elements (MREs) of miR-1, miR-133 and miR-218 to confer TRAIL expression with specificity to bladder cancer cells. Results: Expression of miR-1, miR-133 and miR-218 was greatly decreased in bladder cancer than normal bladder tissue. Luciferase assay showed that application of the 3 MREs was able to restrain exogenous gene expression to within bladder cancer cells. Subsequently, we constructed a recombinant adenovirus with TRAIL expression regulated by MREs of miR-1, miR-133 and miR-218, namely Ad-TRAIL-MRE-1-133-218. qPCR, immunoblotting and ELISA assays demonstrated that Ad-TRAIL-MRE-1-133-218 expressed in bladder cancer cells, rather than normal bladder cells. The differential TRAIL expression also led to selective apoptosis-inducing and growth-inhibiting effect of Ad-TRAIL-MRE-1-133-218 on bladder cancers. Finally, bladder cancer xenograft in mouse models further confirmed that Ad-TRAIL-MRE-1-133-218 effectively suppressed the growth of bladder cancers. Conclusions: Collectively, we demonstrated that MREs-based TRAIL delivery into bladder cancer cells was feasible and efficient for cancer gene therapy. [ABSTRACT FROM AUTHOR]

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: Aims Lipopolysaccharide (LPS) induces cardiomyocyte caspase-3 activation and proinflammatory factors, in particular tumour necrosis factor-alpha (TNF-α) production, both of which contribute to myocardial dysfunction during sepsis. The present study was to investigate the roles of calpain/calpastatin system in cardiomyocyte caspase-3 activation, TNF-α expression, and myocardial dysfunction during LPS stimulation. : Methods and results In cultured adult rat cardiomyocytes, LPS (1 µg/mL) induced calpain and caspase-3 activity, and up-regulated TNF-α expression. These effects of LPS were abrogated by over-expression of calpastatin, an endogenous calpain inhibitor, transfection of calpain-1 siRNA, or various pharmacological calpain inhibitors. Furthermore, blocking gp91phox-NADPH oxidase prevented calpain and caspase-3 activation and decreased TNF-α expression in LPS-stimulated cardiomyocytes. To investigate the role of calpastatin in endotoxaemia, transgenic mice with calpastatin over-expression (CAST-Tg) and wild-type mice were treated with LPS (4 mg/kg, i.p.) or saline in the presence of calpain inhibitor-III (10 mg/kg, i.p.) for 4 h, and their heart function was measured with a Langendorff system. Over-expression of calpastatin significantly attenuated myocardial dysfunction (P < 0.05). Consistently, calpain activity, caspase-3 activity, and TNF-α expression were also reduced in CAST-Tg and calpain inhibitor-III compared with wild-type and vehicle-treated hearts, respectively. : Conclusion gp91phox-NADPH oxidase-mediated calpain-1 activation induces caspase-3 activation and TNF-α expression in cardiomyocytes during LPS stimulation. Over-expression of calpastatin inhibits calpain activation and improves myocardial function in endotoxaemia. The present study suggests that targeting calpain/calpastatin system may be a potential therapeutic intervention for septic hearts. [ABSTRACT FROM AUTHOR]

Insulin resistance induced by a high-fat diet (HFD) is related to metabolic diseases, and sterol O-acyltransferase 1 (SOAT1) is a key enzyme for the biosynthesis of cholesteryl ester. In the present study, wild-type (WT) mice and SOAT1-knockout (KO) mice with a C57BL6 background fed a HFD were used to explore the role of SOAT1 in the hypothalamus. The results show that the WT mice exhibited a significant increase in body weight as well as hepatic histologic changes; they also had a lower glucose and insulin tolerance than the WT mice fed a normal diet. However, the metabolic syndrome was attenuated in the SOAT1-KO HFD-fed mice. With regard to brain function, the SOAT1-KO HFD-fed mice showed improved cognitive function; they also manifested reduced levels of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6, which would otherwise be raised by a HFD. In addition, the HFD led to the overexpression of GFAP and phosphorylated NF-κB in the hypothalamus, changes that were reversed in the SOAT1-KO HFD-fed mice. Moreover, SOAT1-KO mice improved HFD-caused defective hypothalamic insulin resistance, as evidenced by the upregulation of p-insulin receptor (INSR), p-AKT and p-glycogen synthase kinase (GSK)-3β, while the downregulation of p-AMP-activated protein kinase (AMPK)–α and p-acetyl-CoA carboxylase (ACC)–α. In addition, similar results were observed in high fructose (HFR)–stimulated astrocytes (ASTs) isolated from WT or KO mice. These results suggest that SOAT1 plays an important role in hypothalamic insulin sensitivity, linked to cognitive impairment, in HFD-fed mice. [ABSTRACT FROM AUTHOR]