The molecular mechanisms underlying acute leptin and serotonin 2C receptor induced hypophagia remain unclear. Here we show that neuronal and pro-opiomelanocortin (Pomc)-specific loss of transient receptor potential cation 5 (TrpC5) subunits is sufficient to decrease energy expenditure and increase food intake resulting in elevated body weight. Deficiency of Trpc5 subunits in Pomc neurons was also sufficient to block the anorexigenic effects of leptin and serotonin 2C receptor (Ht2Cr) agonists. The loss of acute anorexigenic effects of these receptors was concomitant with a blunted electrophysiological response to both leptin and Ht2Cr agonists in arcuate Pomc neurons. We also demonstrate that the Ht2Cr agonist lorcaserin-induced improvements in glucose and insulin tolerance were blocked by TrpC5 deficiency in Pomc neurons. Together, our results link TrpC5 subunits in the brain with leptin- and serotonin 2C receptor-dependent changes in neuronal activity as well as energy balance, feeding behavior, and glucose metabolism.

Platelets play a multifaceted role in cancer progression and metastasis. Mean platelet volume (MPV) and platelet distribution width (PDW) are commonly used platelet parameters from routine blood test. The aim of the present study was to investigate the correlation between platelet indices and prognosis in patients with non-small cell lung cancer (NSCLC). A total of 270 patients who were diagnosed with NSCLC between January 2009 and December 2009 were retrospectively analyzed. Patients’ characteristics and hematologic tests data at initial diagnosis were collected. The overall survival rate was estimated using Kaplan-Meier method. The prognostic analysis was carried out with univariate and multivariate Cox regressions model. Reduced PDW was significantly correlated with T stage, N stage, TNM stage, and histological type of the disease. Moreover, survival analysis showed that the overall survival of patients with PDW ≥ 16.3% was significantly longer than that of those with PDW < 16.3% (P < 0.001). In multivariate Cox regression model, age, sex, TNM stage, and PDW were identified as independent prognostic factors for overall survival (for PDW, P < 0.001). In conclusion, reduced PDW is an unfavorable predictive factor of NSCLC patient survival. Further studies are warranted.

Altered mean platelet volume (MPV) is implicated in several malignancies. However, the clinicopathological significance and prognostic value of MPV in colorectal cancer (CRC) is still elusive. The purpose of this study was to elucidate the predictive significance of MPV in CRC. The retrospective study recruited 509 consecutive CRC patients between January 2009 and December 2009. The relationships between MPV and clinicopathological characteristics were analyzed. Kaplan-Meier method and Cox regression were used to evaluate the prognostic impact of MPV. Of the 509 CRC patients, high MPV levels were detected in 150 (29.5%) patients. Elevated MPV was associated with tumor differentiation (p < 0.001). Patients with increased MPV had poor overall survival compared with those with normal level (60.0% vs. 83.6%, log-rank test, p = 0.035). Cox regression analysis showed that MPV was an independent prognostic factor in CRC (HR = 1.452, 95% CI = 1.118–1.884, p = 0.005). In conclusion, MPV is easily available in routine blood test. Elevated MPV might act as a marker of prognosis and therapeutic target for CRC.

ObjectiveAdiponectin receptors (AdipoRs) are located on neurons of the hypothalamus involved in metabolic regulation – including arcuate proopiomelanocortin (Pomc) and Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons. AdipoRs play a critical role in regulating glucose and fatty acid metabolism by initiating several signaling cascades overlapping with Leptin receptors (LepRs). However, the mechanism by which adiponectin regulates cellular activity in the brain remains undefined.MethodsIn order to resolve this issue, we utilized neuron-specific transgenic mouse models to identify Pomc and NPY/AgRP neurons which express LepRs for patch-clamp electrophysiology experiments.ResultsWe found that leptin and adiponectin synergistically activated melanocortin neurons in the arcuate nucleus. Conversely, NPY/AgRP neurons were inhibited in response to adiponectin. The adiponectin-induced depolarization of arcuate Pomc neurons occurred via activation of Phosphoinositide-3-kinase (PI3K) signaling, independent of 5′ AMP-activated protein kinase (AMPK) activity. Adiponectin also activated melanocortin neurons at various physiological glucose levels.ConclusionsOur results demonstrate a requirement for PI3K signaling in the acute adiponectin-induced effects on the cellular activity of arcuate melanocortin neurons. Moreover, these data provide evidence for PI3K as a substrate for both leptin and adiponectin to regulate energy balance and glucose metabolism via melanocortin activity.