Search

Background/Aims: Nesfatin-1 (NF-1), an anorexic nucleobindin-2 (NUCB2)-derived hypothalamic peptide, acts as a peripheral cardiac modulator and it can induce negative inotropic effects. However, the mechanisms underlying these effects in cardiomyocytes remain unclear. Methods: Using patch clamp, protein kinase assays, and western blot analysis, we studied the effect of NF-1 on L-type Ca2+ currents (ICa,L) and to explore the regulatory mechanisms of this effect in adult ventricular myocytes. Results: NF-1 reversibly decreased ICa,L in a dose-dependent manner. This effect was mediated by melanocortin 4 receptor (MC4-R) and was associated with a hyperpolarizing shift in the voltage-dependence of inactivation. Dialysis of cells with GDP-β-S or anti-Gβ antibody as well as pertussis toxin pretreatment abolished the inhibitory effects of NF-1 on ICa,L. Protein kinase C (PKC) antagonists abolished NF-1-induced responses, whereas inhibition of PKA activity or intracellular application of the fast Ca2+-chelator BAPTA elicited no such effects. Application of NF-1 increased membrane abundance of PKC theta isoform (PKCθ), and PKCθ inhibition abolished the decrease in ICa,L induced by NF-1. Conclusion: These data suggest that NF-1 suppresses L-type Ca2+ channels via the MC4-R that couples sequentially to the βγ subunits of Gi/o-protein and the novel PKCθ isoform in adult ventricular myocytes. [ABSTRACT FROM AUTHOR]

Objective: This clinical trial investigates whether short-term administration of long chain triglycerides (LCT) has any influence on the immune function in children following gastrointestinal surgery., Methods: Sixty pediatric patients receiving a gastrointestinal operation were randomly divided into the experimental group (n = 36) and the control group (n = 24). After abdominal operation, the subjects received parenteral nutrition (PN) support with or without LCT for 5 days. The patients' fasting blood samples were respectively collected at 24 hours preoperative, then 24 hours and 120 hours postoperative. Blood parameters related to the patients' immune function were measured., Results: Before surgery and LCT treatment, the experimental group and control group did not differ significantly in overall state of health. Except for a small increase of serum IgM at 24 hours postsurgery (p < .05), all parameters representing the patients' immune function showed no significant difference between the LCT group and the control group with respect to peripheral blood mononuclear cell (PBMC), T lymphocyte, CD4, CD8, CD4/CD8, serum immunoglobulin A (IgA), IgG, IgM, complement C3, C4, interleukin (IL)-2, IL-4, IL-10, IL-12, tumor necrosis factor (TNF)-alpha and IFN-gamma (p > .05, respectively) before the operation, 24 hours and 120 hours after the operation., Conclusions: A short-term LCT administration at an appropriate dosage and infusion speed does not alter the pediatric patients' immune function after gastrointestinal surgery. The etiology and clinical significance of the slightly increased IgM 24 hours postsurgery need to be further investigated.

Background: Parenteral nutrition (PN) support containing long-chain triglycerides (LCT) plays a critical supportive role in surgical patients' management. This study aims to investigate the effects of intravenous (IV) LCT emulsion on human immune function in adult patients receiving a gastrointestinal surgical procedure., Methods: Sixty adult patients were randomly assigned either to the LCT treatment group (n = 32) or to the control group (n = 28). After an abdominal operation, the subjects received PN treatment with or without LCT for 5 days. Neutrophil, peripheral blood mononuclear cell (PBMC), lymphocyte and CD4/CD8, serum immunoglobulin A (IgA), IgG, IgM, complement C3 and C4, interleukin (IL)-2, IL-4, IL-10, IL-12, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma were measured and statistically analyzed., Results: The LCT and control groups did not differ significantly at entry in terms of general features. Except for a significant increase of neutrophil number at 24 hours after the surgery in both groups (p < .01), all parameters representing the patients' immune function had no significant difference between the LCT and the control groups with respect to neutrophil and PBMC count, lymphocyte, CD4/CD8, serum IgA, IgG, IgM, complement C3, C4, IL-2, IL-4, IL-10, IL-12, TNF-alpha, and IFN-gamma (p > .05, respectively) 24 hours before the operation, and 24 hours and 120 hours after the operation., Conclusions: The regimens of LCT administration may have diverse effects on human immune function in different patient populations. However, LCT emulsion at an appropriate dose and infusion speed does not alter human immune function of adult patients undergoing moderate gastrointestinal surgery.