Role of cytosolic and calcium independent phospholipases A(2) in insulin secretion impairment of INS-1E cells infected by S. aureus.

Cytosolic PLA2 (cPLA2) and Ca(2+)-independent PLA2 (iPLA2) play a significant role in insulin ß-cells secretion. Bacterial infections may be responsible of the onset of diabetes. The mechanism by which Staphylococcus aureus infection of INS-1 cells alters glucose-induced insulin secretion has been examined. After acute infection, insulin secretion and PLA2 activities significantly increased. Moreover, increased expressions of phospho-cPLA2, phospho-PKCα and phospho-ERK 1/2 were observed. Chronic infection causes a decrease in insulin release and a significant increase of iPLA2 and COX-2 protein expression. Moreover, insulin secretion in infected cells could be restored using specific siRNAs against iPLA2 isoform and specific COX-2 inhibitor.

Laparoscopic staging of apparent early stage ovarian cancer: results of a large, retrospective, multi-institutional series.

OBJECTIVE: The aim of this study is to analyze the safety, adequacy, perioperative and survival figures in a large series of laparoscopic staging of patients with apparent early stage ovarian malignancies (ESOM). PATIENTS AND METHODS: Retrospective data from seven gynecologic oncology service databases were searched for ESOM patients undergoing immediate laparoscopic staging or delayed laparoscopic staging after an incidental diagnosis of ESOM. Between May 2000 and February 2014, 300 patients were selected: 150 had been submitted to immediate laparoscopic staging (Group 1), while 150 had undergone delayed laparoscopic staging (Group 2) of ESOM. All surgical, pathologic, and oncologic outcome data were analyzed in each group and a comparison between the two was carried out. RESULTS: Longer operative time, higher blood loss, more frequently spillage/rupture of ovarian capsule and conversion to laparotomy occurred in Group 1. No significant differences of post-operative complications were observed between the two groups. Histological data revealed more frequently serous tumors (0.06), Grade 3 (p=0.0007) and final up-staging (p=0.001) in Group 1. Recurrence and death of disease were documented in 25 (8.3%), and 10 patients (3.3%%), respectively. The 3-year disease free survival (DFS) and overall survival (OS) rates were 85.1%, and 93.6%, respectively in the whole series. There was no difference between Group 1 and Group 2 in terms of DFS (p value=0.39) and OS (p value=0.27). CONCLUSION: In this very large multi-institutional study, it appears that patients with apparent ESOM can safely undergo laparoscopic surgical management.

Adiponectin increases glucose-induced insulin secretion through the activation of lipid oxidation.

The expression of adiponectin receptors has been demonstrated in human and rat pancreatic beta cells, where globular (g) adiponectin rescues rat beta cells from cytokine and fatty acid-induced apoptosis. The aim of our study was to evaluate whether adiponectin has a direct effect on insulin secretion and the metabolic pathways involved. Purified human pancreatic islets and rat beta cells (INS-1E) were exposed (1 h) to g-adiponectin, and glucose-induced insulin secretion was measured. A significant increase in glucose-induced insulin secretion was observed in the presence of g-adiponectin (1 nmol/l) with respect to control cells in both human pancreatic islets (n = 5, p < 0.05) and INS-1E cells (n = 5, p < 0.001). The effect of globular adiponectin on insulin secretion was independent of AMP-dependent protein kinase (AMPK) activation or glucose oxidation. In contrast, g-adiponectin significantly increased oleate oxidation (n = 5, p < 0.05), and the effect of g-adiponectin (p < 0.001) on insulin secretion by INS-1E was significantly reduced in the presence of etomoxir (1 µmol/l), an inhibitor of fatty acid beta oxidation. g-Adiponectin potentiates glucose-induced insulin secretion in both human pancreatic islets and rat beta cells via an AMPK independent pathway. Increased fatty acid oxidation rather than augmented glucose oxidation is the mechanism responsible. Overall, our data indicate that, in addition to its anti-apoptotic action, g-adiponectin has another direct effect on beta cells by potentiating insulin secretion. Adiponectin, therefore, in addition to its well-known effect on insulin sensitivity, has important effects at the pancreatic level.

Effect of the intravenous anesthetic 2,6-diisopropylphenol on respiration and energy production by rat brain synaptosomes.

The sensitivity of the mitochondrial energy production system to propofol (DPP) has been investigated in rat brain synaptosomes. DPP at 0.8 mM concentration produced a partial inhibition of coupled respiration, an apparent decrease of the oxygen uptake stimulation induced by CCCP and a full inhibition of the mitochondrial ATP production by synaptosomes. Higher concentrations of DPP (1 mM) fully abolish uncoupler-dependent stimulation and at 1.3 mM DPP also coupled respiration is completely blocked. Similar results were obtained when dinitrophenol replaced CCCP and phenol or propylbenzene replaced DPP. The presence of the alkyl residues seems critical for the DPP effect. In the presence of 30 mM glutamate both respiration and ATP production are enhanced but DPP effects are similar to those obtained in the absence of glutamate.