We conducted a meta-analysis of randomized controlled trials to examine the association of mobile phone intervention with net change in weight-related measures among overweight and obese adults. We searched electronic databases and conducted a bibliography review to identify articles published between the inception date of each database and March 27, 2014. Fourteen trials (including 1,337 participants in total) that met the eligibility criteria were included. Two investigators independently abstracted information on study characteristics and study outcomes. Net change estimates comparing the intervention group with the control group were pooled across trials using random-effects models. Compared with the control group, mobile phone intervention was associated with significant changes in body weight and body mass index (weight (kg)/height (m)(2)) of -1.44 kg (95% confidence interval (CI): -2.12, -0.76) and -0.24 units (95% CI: -0.40, -0.08), respectively. Subgroup analyses revealed that the associations were consistent across study-duration and intervention-type subgroups. For example, net body weight changes were -0.92 kg (95% CI: -1.58, -0.25) and -1.85 kg (95% CI: -2.99, -0.71) in trials of shorter (<6 months) and longer (≥6 months) duration, respectively. These findings provide evidence that mobile phone intervention may be a useful tool for promoting weight loss among overweight and obese adults.

The protein, thyroid hormone‐responsive SPOT 14 homolog (Thrsp), has been reported to be a lipogenic gene in cultured hepatocytes, implicating an important role of Thrsp in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Thrsp expression is known to be regulated by a variety of transcription factors, including thyroid hormone receptor, pregnane X receptor, and constitutive androstane receptor. Emerging in vitro evidence also points to a critical role of liver X receptor (LXR) in regulating Thrsp transcription in hepatocytes. In the present study, we showed that Thrsp was up‐regulated in livers of db/db mice and high‐fat‐diet–fed mice, two models of murine NAFLD. Hepatic overexpression of Thrsp increased triglyceride accumulation with enhanced lipogenesis in livers of C57Bl/6 mice, whereas hepatic Thrsp gene silencing attenuated the fatty liver phenotype in db/db mice. LXR activator TO901317 induced Thrsp expression in livers of wild‐type (WT) and LXR‐β gene‐deficient mice, but not in LXR‐α or LXR‐α/β double‐knockout mice. TO901317 treatment significantly enhanced hepatic sterol regulatory element‐binding protein 1c (SREBP‐1c) expression and activity in WT mice, but failed to induce Thrsp expression in SREBP‐1c gene‐deficient mice. Sequence analysis revealed four LXR response‐element–like elements and one sterol regulatory element (SRE)‐binding site within a −2,468 ∼+1‐base‐pair region of the Thrsp promoter. TO901317 treatment and LXR‐α overexpression failed to induce, whereas overexpression of SREBP‐1c significantly increased Thrsp promoter activity. Moreover, deletion of the SRE site completely abolished SREBP‐1c–induced Thrsp transcription. Conclusion: Thrsp is a lipogenic gene in the liver that is induced by the LXR agonist through an LXR‐α–mediated, SREBP‐1c–dependent mechanism. Therefore, Thrsp may represent a potential therapeutic target for the treatment of NAFLD. (Hepatology 2013;58:617–628)

analysis reveals diabetic kidney as a ketogenic organ in type 2 diabetes. Am J Physiol Endocrinol Metab 300: E287-E295, 2011. First published October 19, 2010 doi:10.1152/ajpendo.00308.2010 is the leading cause of end-stage renal disease. To date, the molecular mechanisms of DN remain largely unclear. The present study aimed to identify and characterize novel proteins involved in the development of DN by a proteomic approach. Proteomic analysis revealed that 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase 2 (HMGCS2), the key enzyme in ketogenesis, was increased fourfold in the kidneys of type 2 diabetic db/db mice. Consistently, the activity of HMGCS2 in kidneys and 24-h urinary excretion of the ketone body ␤-hydroxybutyrate (␤-HB) were significantly increased in db/db mice. Immunohistochemistry, immunofluorescence, and real-time PCR studies further demonstrated that HMGCS2 was highly expressed in renal glomeruli of db/db mice, with weak expression in the kidneys of control mice. Because filtered ketone bodies are mainly reabsorbed in the proximal tubules, we used RPTC cells, a rat proximal tubule cell line, to examine the effect of the increased level of ketone bodies. Treating cultured RPTC cells with 1 mM ␤-HB significantly induced transforming growth factor-␤1 expression, with a marked increase in collagen I expression. ␤-HB treatment also resulted in a marked increase in vimentin protein expression and a significant reduction in E-cadherin protein levels, suggesting an enhanced epithelial-to-mesenchymal transition in RPTCs. Collectively, these findings demonstrate that diabetic kidneys exhibit excess ketogenic activity resulting from increased HMGCS2 expression. Enhanced ketone body production in the diabetic kidney may represent a novel mechanism involved in the pathogenesis of DN.

Doxorubicin (DOX) is an anthracycline antibiotic utilized in antitumor therapy; however, its clinical use is frequently impeded by renal toxic effects. As peroxisome proliferator-activated receptor-α (PPAR-α) has renoprotective effects in drug-related kidney injuries, we tested its ability to inhibit DOX-induced renal injury. Although both male PPAR-α knockout mice and their wild-type littermates (pure 129/SvJ background) had significant proteinuria 4 weeks after DOX treatment, those with deletion of PPAR-α had more severe proteinuria. This was associated with more serious podocyte foot process effacement compared with wild-type mice. In contrast, the PPAR-α agonist fenofibrate effectively reduced proteinuria and attenuated DOX-induced podocyte foot process effacement. Consistently, glomerular nephrin expression was significantly lower in the knockout compared with wild-type mice following DOX treatment. Fenofibrate therapy significantly blunted the reduction in glomerular nephrin levels in DOX-treated wild-type mice. In cultured podocytes, DOX induced apoptosis, increased cleaved caspase-3 levels, and decreased Bcl-2 expression, all attenuated by pretreatment with fenofibrate. Thus, PPAR-α deficiency exacerbates DOX-related renal injury, in part, due to increased podocyte apoptosis.

Cells residing in the hypertonic, hypoxic renal medulla depend on dynamic adaptation mechanisms to respond to changes in energy supply and demand. The serine/threonine kinase 5Ј-AMP protein kinase (AMPK) is a sensor of cellular energy status, but whether it contributes to the survival of cells in the renal medulla is unknown. Here, hypertonic conditions induced a decrease in AMPK phosphorylation within 12 hours in renal medullary interstitial cells (RMIC), followed by a gradual return to baseline levels. Activation of AMPK markedly increased hypertonicity-induced apoptosis of RMICs and suppressed both hypertonicity-induced NFB nuclear translocation and cyclooxygenase-2 (COX-2) activation; overexpression of COX-2 significantly attenuated these effects. AMPK activation also markedly reduced generation of reactive oxygen species and nuclear expression of tonicity-responsive enhancer-binding protein, which prevented upregulation of osmoprotective genes. In vivo, pharmacologic activation of AMPK led to massive apoptosis of RMICs and renal dysfunction in the setting of water deprivation in mice. Taken together, these results identify a critical role for AMPK in the maintenance of RMIC viability and suggest that AMPK modulates the NFB-COX-2 survival pathway in the renal medulla. Furthermore, this study raises safety concerns for the development of AMPK activators as anti-diabetic drugs, especially for patients prone to dehydration.