Postprandial hyperinsulinemic hypoglycemia, although rare, is a well-documented complication that can manifest after upper gastrointestinal surgery. Despite its potential for severe morbidity, the underlying pathogenesis and optimal treatment strategies for this condition remain insufficiently understood. This report presents a compelling case of postprandial hypoglycemia following Billroth-II gastrojejunostomy, characterized by a marked increase in postprandial insulin levels, accompanied by the exaggerated response of incretin hormones.
View Article and Find Full Text PDFTherapeutic approach for NAFLD is limited and there are no approved drugs. Pioglitazone (PGZ), a thiazolidinedione (TZD) that acts via peroxisome proliferator activated receptor gamma (PPARγ) is the only agent that has shown consistent benefit and efficacy in clinical trials. However, the mechanism of its therapeutic effect on NAFLD remains unclear.
View Article and Find Full Text PDFContext: The gene encodes pancreatic and duodenal homeobox, a critical transcription factor for pancreatic β-cell differentiation and maintenance of mature β-cells. Heterozygous loss-of-function mutations cause -MODY (MODY4).
Case Description: Our patient is an 18-year-old lean man who developed diabetes at 16 years of age.
Klinefelter syndrome (KS) is frequently complicated by diabetes. However, it is severely underdiagnosed due to a lack of reliable screening methods. We diagnosed two patients with KS at the Center for Diabetes and Endocrinology, Tazuke Kofukai Medical Research Institute Kitano Hospital, Osaka, Japan.
View Article and Find Full Text PDFA patient with mitochondrial diabetes mellitus developed diabetic ketoacidosis. During insulin treatment, although diabetic ketoacidosis improved, lactic acidosis unexpectedly worsened. This clinical course, named "switched metabolic acidosis," could reflect the unique pathophysiology of the mitochondrial disorder.
View Article and Find Full Text PDFObesity causes excess fat accumulation in white adipose tissues (WAT) and also in other insulin-responsive organs such as the skeletal muscle, increasing the risk for insulin resistance, which can lead to obesity-related metabolic disorders. Peroxisome proliferator-activated receptor-α (PPARα) is a master regulator of fatty acid oxidation whose activator is known to improve hyperlipidemia. However, the molecular mechanisms underlying PPARα activator-mediated reduction in adiposity and improvement of metabolic disorders are largely unknown.
View Article and Find Full Text PDFSeipin, encoded by BSCL2 gene, is a protein whose physiological functions remain unclear. Mutations of BSCL2 cause the most-severe form of congenital generalized lipodystrophy (CGL). BSCL2 mRNA is highly expressed in the brain and testis in addition to the adipose tissue in human, suggesting physiological roles of seipin in non-adipose tissues.
View Article and Find Full Text PDFNonalcoholic fatty liver disease (NAFLD) is recognized as the hepatic component of the metabolic syndrome. Although NAFLD is a major cause of cirrhosis and cancer of the liver of unknown cause, no established pharmacological treatment for NAFLD has been established yet. It has been reported that leptin treatment improved fatty liver dramatically as well as insulin resistance and hyperphagia in patients with lipodystrophy.
View Article and Find Full Text PDFLeptin may reduce pancreatic lipid deposition, which increases with progression of obesity and can impair β-cell function. The insulinotropic effect of glucagon-like peptide-1 (GLP-1) and the efficacy of GLP-1 receptor agonist are reduced associated with impaired β-cell function. In this study, we examined whether leptin could restore the efficacy of exenatide, a GLP-1 receptor agonist, in type 2 diabetes with increased adiposity.
View Article and Find Full Text PDFLeptin is one of the key molecules in maintaining energy homeostasis. Although genetically leptin-deficient Lep(ob)/Lep(ob) mice have greatly contributed to elucidating leptin physiology, the use of more than one species can improve the accuracy of analysis results. Using the N-ethyl-N-nitrosourea mutagenesis method, we generated a leptin-deficient Lep(mkyo)/Lep(mkyo) rat that had a nonsense mutation (Q92X) in leptin gene.
View Article and Find Full Text PDFBackground: AMPK activation promotes glucose and lipid metabolism.
Results: Hepatic AMPK activities were decreased in fatty liver from lipodystrophic mice, and leptin activated the hepatic AMPK via the α-adrenergic effect.
Conclusion: Leptin improved the fatty liver possibly by activating hepatic AMPK through the central and sympathetic nervous systems.
Context: Lipodystrophy is a disease characterized by a paucity of adipose tissue and low circulating concentrations of adipocyte-derived leptin. Leptin-replacement therapy improves eating and metabolic disorders in patients with lipodystrophy.
Objective: The aim of the study was to clarify the pathogenic mechanism of eating disorders in lipodystrophic patients and the action mechanism of leptin on appetite regulation.
Am J Physiol Endocrinol Metab
April 2012
Leptin enhances insulin sensitivity in addition to reducing food intake and body weight. Recently, amylin, a pancreatic β-cell-derived hormone, was shown to restore a weight-reducing effect of leptin in leptin-resistant diet-induced obesity. However, whether amylin improves the effect of leptin on insulin sensitivity in diet-induced obesity is unclear.
View Article and Find Full Text PDFPostprandial hyperglycemia and hyperlipidemia are considered risk factors for cardiovascular disease. This study was designed to elucidate whether improving the postprandial state by voglibose, an alpha-glucosidase inhibitor, leads to the reduction of oxidative stress markers and soluble adhesion molecules in obese type 2 diabetic patients. A total of 30 Japanese obese type 2 diabetic patients were randomly assigned and treated for 3 weeks with either diet alone (the control group) or diet plus voglibose (0.
View Article and Find Full Text PDFLeptin is a major adipocyte-derived hormone that is involved in the regulation of food intake and energy expenditure. Plasma leptin concentrations are elevated in obese subjects, suggesting its pathophysiological role in obesity-related lifestyle-related diseases. We have recently succeeded in the generation of transgenic skinny mice overexpressing leptin.
View Article and Find Full Text PDFLipoatrophic diabetes is caused by a deficiency of adipose tissue and is characterized by severe insulin resistance, hypoleptinemia, and hyperphagia. The A-ZIP/F-1 mouse (A-ZIPTg/+) is a model of severe lipoatrophic diabetes and is insulin resistant, hypoleptinemic, hyperphagic, and shows severe hepatic steatosis. We have also produced transgenic "skinny" mice that have hepatic overexpression of leptin (LepTg/+) and no adipocyte triglyceride stores, and are hypophagic and show increased insulin sensitivity.
View Article and Find Full Text PDFGhrelin, an endogenous ligand for growth hormone secretagogue (GHS) receptor originally isolated from the stomach, occurs in the hypothalamic arcuate nucleus and may play a role in energy homeostasis. Synthetic GHSs have activated the hypothalamic arcuate neurons containing neuropeptide Y (NPY), suggesting the involvement of NPY in some of ghrelin actions. This study was designed to elucidate the role of ghrelin in the regulation of food intake.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
February 2001
Leptin is an adipocyte-derived circulating satiety factor with a variety of biological effects. Evidence has accumulated suggesting that leptin may modulate glucose and lipid metabolism. In the present study, we examined lipid metabolism in transgenic skinny mice with elevated plasma leptin concentrations.
View Article and Find Full Text PDFTo explore the pathophysiological role of leptin in obesity-related hypertension, we examined cardiovascular phenotypes of transgenic skinny mice whose elevated plasma leptin concentrations are comparable to those seen in obese subjects. We also studied genetically obese KKA(y) mice with hyperleptinemia, in which hypothalamic melanocortin system is antagonized by ectopic expression of the agouti protein. Systolic blood pressure (BP) and urinary catecholamine excretion are elevated in transgenic skinny mice relative to nontransgenic littermates.
View Article and Find Full Text PDFExcess or loss of body fat can be associated with infertility, suggesting that adequate fat mass is essential for proper reproductive function. Leptin is an adipocyte-derived hormone that is involved in the regulation of food intake and energy expenditure, and its synthesis and secretion are markedly increased in obesity. Short-term administration of leptin accelerates the onset of puberty in normal mice and corrects the sterility of leptin-deficient ob/ob mice.
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