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1.
Am J Emerg Med ; 55: 226.e3-226.e6, 2022 05.
Article in English | MEDLINE | ID: mdl-34974951

ABSTRACT

Accidental hypothermia is a life-threatening medical condition, which requires the appropriate rewarming strategy with careful monitoring. Active core rewarming is often necessary in the management of severe hypothermia. However, especially in the emergent clinical setting, immediate establishment of a reliable route for active core rewarming is difficult. Severe accidental hypothermia in patients dependent on peritoneal dialysis or combination of hemodialysis with peritoneal dialysis is extremely rare, and the ideal rewarming procedure for these patients is unclear. To our knowledge, this is the first case report illustrating the application of an indwelling peritoneal dialysis catheter to active core rewarming in the management of severe accidental hypothermia. A 64-year-old female with type 1 diabetes and end-stage renal disease (ESRD) on combination of hemodialysis with peritoneal dialysis was delivered to our hospital due to severe accidental hypothermia. On presentation, she was unresponsive and her core temperature was 22.8 °C. Since rewarming by an electric blanket and warmed saline infusion was ineffective, infusion of warmed peritoneal dialysis solution via an indwelling peritoneal dialysis catheter was performed in the emergency room. In the next few hours, her body temperature recovered to normal level, and she regained consciousness. During resuscitation, complications related to rewarming, such as arrhythmia or hypotension, were not observed. She was discharged without any sequelae. Indwelling peritoneal dialysis catheters, if available, could be utilized as the safe and reliable route for active core rewarming in ESRD patients.


Subject(s)
Hypothermia , Kidney Failure, Chronic , Peritoneal Dialysis , Catheters/adverse effects , Female , Humans , Hypothermia/complications , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/therapy , Male , Middle Aged , Peritoneal Dialysis/adverse effects , Rewarming/methods
2.
Thyroid ; 27(7): 894-901, 2017 07.
Article in English | MEDLINE | ID: mdl-28537531

ABSTRACT

BACKGROUND: The programmed cell death-1 (PD-1) pathway is a novel therapeutic target in immune checkpoint therapy for cancer. It consists of the PD-1 receptor and its two ligands, programmed death-ligand 1 (PD-L1) and programmed death-ligand 2 (PD-L2). Nivolumab is an anti-PD-1 monoclonal antibody approved for malignant melanoma, advanced non-small cell lung cancer, and advanced renal cell carcinoma in Japan. Thyrotoxicosis and hypothyroidism have both been reported in international Phase 3 studies and national post-marketing surveillance of nivolumab in Japan. METHODS: This study analyzed five consecutive cases with thyroid dysfunction associated with nivolumab therapy. Second, it examined the mRNA and protein expressions of PD-L1 and PD-L2 by reverse transcription polymerase chain reaction and Western blotting. RESULTS: All patients were diagnosed with painless thyroiditis. Thyrotoxicosis developed within four weeks from the first administration of nivolumab and normalized within four weeks of onset in three of the five patients. Hypothyroidism after transient thyrotoxicosis developed in two patients, and preexisting hypothyroidism persisted in one patient. The other two patients were treated with glucocorticoids and discontinued nivolumab therapy for comorbid adverse events. One did not develop hypothyroidism, and the other developed mild, transient hypothyroidism. In addition, it was verified that normal thyroid tissue expresses PD-L1 and PD-L2 mRNA and those proteins. CONCLUSIONS: In the present cases, nivolumab-induced thyrotoxicosis seemed to be associated with painless thyroiditis, while no patient with Graves' disease was observed. A transient and rapid course with subsequent hypothyroidism was observed in nivolumab-induced thyroiditis. In addition, it was verified that PD-L1 and PD-L2 are expressed in normal thyroid tissue. This suggests that nivolumab therapy reduces immune tolerance, even in normal thyroid tissue, and leads to the development of thyroiditis. Treating thyrotoxicosis with only supportive care and considering levothyroxine replacement therapy once subsequent hypothyroidism occurs is proposed. Further investigations are required to confirm whether glucocorticoid therapy and discontinuation of nivolumab therapy prevent subsequent hypothyroidism.


Subject(s)
Antibodies, Monoclonal/adverse effects , Antineoplastic Agents/adverse effects , Thyroiditis/chemically induced , Thyroiditis/diagnosis , Thyrotoxicosis/chemically induced , Thyrotoxicosis/diagnosis , Aged , Breast Neoplasms/drug therapy , Female , Humans , Lung Neoplasms/drug therapy , Male , Melanoma/drug therapy , Middle Aged , Nivolumab , Skin Neoplasms/drug therapy , Symptom Assessment , Thyroiditis/blood , Thyrotoxicosis/blood , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
3.
Adv Exp Med Biol ; 871: 147-62, 2015.
Article in English | MEDLINE | ID: mdl-26374217

ABSTRACT

The regulations for the human use of advanced therapy medical products such as gene and cell therapy products have evolved in accordance with advance of clinical experience, scientific knowledge, and social acceptance to these technologies. In Japan, two laws, the Pharmaceuticals and Medical Devices (PMD) Act and the Act on the Safety of Regenerative Medicine (ASRM), were enacted in November 2014. The PMD Act defines regenerative medical products for the first time and introduces a system for the conditional and time-limited marketing authorization of regenerative medical products. Under ASRM, the responsibilities of medical institutions to ensure the safety and provide transparency of such medical technologies are described. Amendments to accompanying guidelines for these two Acts are currently in preparation. It is expected that the new legislative frameworks will promote the timely development of new products and technologies, to bring safe and effective regenerative medicines to Japanese patients.


Subject(s)
Cell- and Tissue-Based Therapy/ethics , Drug and Narcotic Control/legislation & jurisprudence , Genetic Therapy/legislation & jurisprudence , Marketing/legislation & jurisprudence , Regenerative Medicine/legislation & jurisprudence , Translational Research, Biomedical/legislation & jurisprudence , Animals , Cell- and Tissue-Based Therapy/methods , Clinical Trials as Topic , Genetic Therapy/ethics , Humans , Japan , Patient Safety/legislation & jurisprudence , Practice Guidelines as Topic , Quality Control , Regenerative Medicine/ethics , Research Design , Translational Research, Biomedical/ethics
4.
Obesity (Silver Spring) ; 21(9): E350-3, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23703886

ABSTRACT

OBJECTIVE: To elucidate early change of intra-abdominal fat in response to calorie restriction in patients with obesity by weekly evaluation using a dual bioelectrical impedance analysis (Dual BIA) instrument. METHODS: For 67 Japanese patients with obesity, diabetes, or metabolic syndrome, intra-abdominal fat area (IAFA), initially with both Dual BIA and computed tomography (CT), and in subsequent weeks of calorie restriction, with Dual BIA were measured. RESULTS: IAFA by Dual BIA (Dual BIA-IAFA) correlated well with IAFA by CT (CT-IAFA) in obese patients (r = 0.821, P < .0001, n = 67). Ten males and 9 females (age 49.0 ± 14.4 years, BMI 33.2 ± 7.3 kg/m2) lost more than 5% of baseline body weight (BW) in 3 weeks, and their Dual BIA-IAFA, BW, and WC decreased by 18.9%, 5.3%, and 3.8%, respectively (P < .05, ANCOVA). CONCLUSION: Dual BIA instrument could detect the weekly change of Dual BIA-IAFA under calorie restriction in obese patients and demonstrated a substantially larger change of IAFA compared with changes of BW and WC in early weeks. This observation corroborates the significance of evaluating IAFA as a biomarker for obesity, and indicates the clinical usefulness of the Dual BIA instrument.


Subject(s)
Adiposity/physiology , Caloric Restriction , Intra-Abdominal Fat/physiopathology , Obesity/physiopathology , Waist Circumference/physiology , Weight Loss/physiology , Adult , Biomarkers/metabolism , Diabetes Mellitus/diagnostic imaging , Diabetes Mellitus/metabolism , Diabetes Mellitus/physiopathology , Electric Impedance , Female , Humans , Intra-Abdominal Fat/diagnostic imaging , Intra-Abdominal Fat/metabolism , Japan , Male , Metabolic Syndrome/diagnostic imaging , Metabolic Syndrome/metabolism , Metabolic Syndrome/physiopathology , Middle Aged , Obesity/diagnosis , Obesity/diagnostic imaging , Obesity/diet therapy , Tomography, X-Ray Computed
5.
Nihon Rinsho ; 71(2): 262-5, 2013 Feb.
Article in Japanese | MEDLINE | ID: mdl-23631203

ABSTRACT

Two novel bioelectrical impedance analysis (BIA) methods have been developed recently for evaluation of intra-abdominal fat accumulation. Both methods use electrodes that are placed on abdominal wall and allow evaluation of intra-abdominal fat area (IAFA) easily without radiation exposure. Of these, "abdominal BIA" method measures impedance distribution along abdominal anterior-posterior axis, and IAFA by BIA method(BIA-IAFA) is calculated from waist circumference and the voltage occurring at the flank. Dual BIA method measures impedance of trunk and body surface at the abdominal level and calculates BIA-IAFA from transverse and antero-posterior diameters of the abdomen and the impedance of trunk and abdominal surface. BIA-IAFA by these two BIA methods correlated well with IAFA measured by abdominal CT (CT-IAFA) with correlatipn coefficient of 0.88 (n = 91, p < 0.0001) for the former, and 0.861 (n = 469, p < 0.01) for the latter. These new BIA methods are useful for evaluating abdominal adiposity in clinical study and routine clinical practice of metabolic syndrome and obesity.


Subject(s)
Abdominal Fat/chemistry , Abdominal Fat/anatomy & histology , Adiposity , Body Composition/physiology , Body Mass Index , Electric Impedance , Humans , Obesity/diagnosis
6.
Article in English | MEDLINE | ID: mdl-23060233

ABSTRACT

OBJECTIVE: To investigate the significance of intra-abdominal fat area (IAFA) on new onset of individual components of the metabolic syndrome: high blood pressure, dyslipidemia, or hyperglycemia. METHODS: We conducted a longitudinal study using checkup data of a hospital from 1994 to 2010. Of 25,255 subjects, we examined 1,380 Japanese, who underwent computed tomography to measure IAFA and had no metabolic syndrome components at baseline. RESULTS: During 3.6 years of the mean follow-up period, one of metabolic syndrome components occurred in 752 subjects. Of three components, high blood pressure was more prevalent. The multiple Cox regression analysis disclosed that IAFA is significantly associated with onset of metabolic syndrome components (HR: 1.05 per 10 cm(2), 95%CI: 1.03-1.07). This finding was independent of BMI, and significant even in non-obese individuals with body mass index <25 kg/m(2). CONCLUSIONS: MERLOT study demonstrates that IAFA is an independent predictor for new onset of individual components of the metabolic syndrome, even in non-obese healthy Japanese.


Subject(s)
Intra-Abdominal Fat/metabolism , Metabolic Syndrome/metabolism , Obesity, Abdominal/metabolism , Adult , Blood Pressure , Body Mass Index , Dyslipidemias/complications , Female , Health , Humans , Hyperglycemia/complications , Japan , Kaplan-Meier Estimate , Longitudinal Studies , Male , Metabolic Syndrome/complications , Metabolic Syndrome/diagnostic imaging , Metabolic Syndrome/physiopathology , Middle Aged , Obesity, Abdominal/complications , Proportional Hazards Models , Risk Factors , Tomography, X-Ray Computed , Young Adult
7.
Dent Mater J ; 30(2): 127-35, 2011.
Article in English | MEDLINE | ID: mdl-21415552

ABSTRACT

The purpose of the current study was to evaluate the influence of light sources on the mechanical properties and wear characteristics of indirect composite materials. The two composite materials used were Estenia C&B and Epricord. The three laboratory polymerization units used, of which the wavelength range was 400-500 nm, were Hyper LII (two metal halide lamps of 4.82 mW/cm(2)), α-Light II (one halogen lamp and two fluorescent tubes of 3.60 mW/cm(2)), and Labolight LV-II (three fluorescent tubes of 0.63 mW/cm(2)). Three-body wear test was performed using indirect composite plate specimens, a gold alloy antagonist, and a polymer slurry. Wear depths of Estenia C&B polymerized with Hyper LII, α-Light II, and Labolight LV-II were 5.7, 18.5, and 64.2 µm respectively, whereas those of Epricord were 12.9, 18.7, and 48.5 µm respectively. Results showed that, after 100,000 cycles of localized loading, high-intensity light sources were effective in enhancing the wear resistance of both composite materials.


Subject(s)
Composite Resins/radiation effects , Curing Lights, Dental/classification , Dental Materials/radiation effects , Laboratories, Dental , Carbon Compounds, Inorganic/chemistry , Composite Resins/chemistry , Dental Materials/chemistry , Dental Polishing , Dental Stress Analysis/instrumentation , Gold Alloys/chemistry , Hardness , Humans , Materials Testing , Methacrylates/chemistry , Methacrylates/radiation effects , Microscopy, Confocal , Microscopy, Electron, Scanning , Pliability , Polymerization , Polymethyl Methacrylate/chemistry , Polyurethanes/chemistry , Polyurethanes/radiation effects , Radiation Dosage , Silicon Compounds/chemistry , Stress, Mechanical , Surface Properties , Temperature , Time Factors , Water/chemistry
8.
Hypertens Res ; 33(6): 600-6, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20379187

ABSTRACT

The Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial assessed cardiovascular outcomes in high-risk hypertensive patients receiving either candesartan or amlodipine. The aim of this study was to examine the role of pre-existing diabetes or obesity on these outcomes as a sub-analysis of the trial. We examined the influence of pre-existing diabetes on cardiovascular morbidity and mortality using a multivariate Cox regression model. The cardiovascular morbidity and mortality of candesartan and amlodipine were compared between subgroups with or without pre-existing diabetes or by body mass index (BMI) category, and new-onset diabetes was compared by BMI category. Pre-existing diabetes greatly increased the cardiovascular mortality and morbidity, regardless of the allocated drugs. Furthermore, all-cause mortality was significantly higher with amlodipine than with candesartan among patients with BMI >or=27.5 kg m(-2) (adjusted hazard ratio (HR)=0.32; range=0.13-0.75; P=0.009). New-onset diabetes occurred significantly less frequently with candesartan than with amlodipine, with an adjusted HR of 0.66 (P=0.043). Furthermore, the increase in new-onset diabetes was dependent on BMI among patients receiving amlodipine, whereas no such dependency was observed for candesartan (interaction P=0.016). In conclusion, preexisting diabetes increased the risk of experiencing a cardiovascular event among high-risk Japanese hypertensive patients. Candesartan treatment may suppress all-cause death and reduce the incidence of new-onset diabetes in patients with obesity.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Antihypertensive Agents/therapeutic use , Benzimidazoles/therapeutic use , Cardiovascular Diseases/drug therapy , Diabetes Mellitus, Type 2/complications , Hypertension/drug therapy , Obesity/complications , Tetrazoles/therapeutic use , Aged , Amlodipine/therapeutic use , Biphenyl Compounds , Body Mass Index , Cardiovascular Diseases/complications , Cardiovascular Diseases/mortality , Diabetes Mellitus, Type 2/epidemiology , Female , Humans , Hypertension/complications , Hypertension/mortality , Incidence , Japan/epidemiology , Male , Middle Aged , Obesity/epidemiology , Randomized Controlled Trials as Topic , Treatment Outcome
9.
Diabetes Care ; 33(5): 1122-7, 2010 May.
Article in English | MEDLINE | ID: mdl-20185746

ABSTRACT

OBJECTIVE: Hypertensive patients have an increased risk of developing diabetes. Accumulating evidence suggests a close relation between metabolic disturbance and increased arterial stiffness. Here, we examined the association between pulse pressure and the risk of new-onset diabetes in high-risk Japanese hypertensive patients. RESEARCH DESIGN AND METHODS: The Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial examined the effects of candesartan and amlodipine on the incidence of cardiovascular events in 4,728 high-risk Japanese hypertensive patients. In the present study, we analyzed the relationship between pulse pressure at baseline and new-onset diabetes in 2,685 patients without diabetes at baseline (male 1,471; mean age 63.7 years; mean BMI 24.8 kg/m(2)) as a subanalysis of the CASE-J trial. RESULTS: During 3.3 +/- 0.8 years of follow-up, 97 patients (3.6%) developed diabetes. In multiple Cox regression analysis, pulse pressure was an independent predictor for new-onset diabetes (hazard ratio [HR] per 1 SD increase 1.44 [95% CI 1.15-1.79]) as were male sex, BMI, and additional use of diuretics, whereas age and heart rate were not. Plots of HRs for new-onset diabetes considering both systolic and diastolic blood pressure (DBP) revealed that a higher pulse pressure with a lower DBP, indicating that the increased pulse pressure was largely due to increased arterial stiffness, was strongly associated with the risk of new-onset diabetes. CONCLUSIONS: Pulse pressure is an independent predictor of new-onset diabetes in high-risk Japanese hypertensive patients. Increased arterial stiffness may be involved in the development of diabetes.


Subject(s)
Antihypertensive Agents/therapeutic use , Benzimidazoles/therapeutic use , Blood Pressure , Diabetes Mellitus, Type 2/mortality , Hypertension/drug therapy , Hypertension/mortality , Tetrazoles/therapeutic use , Age of Onset , Aged , Asian People/statistics & numerical data , Biphenyl Compounds , Body Mass Index , Diabetes Mellitus, Type 2/diagnosis , Female , Follow-Up Studies , Humans , Hypertension/diagnosis , Male , Middle Aged , Multicenter Studies as Topic , Outcome Assessment, Health Care , Predictive Value of Tests , Proportional Hazards Models , Randomized Controlled Trials as Topic , Risk Factors
10.
Nihon Rinsho ; 67(2): 229-35, 2009 Feb.
Article in Japanese | MEDLINE | ID: mdl-19202893

ABSTRACT

Obesity is recognized as a disease when it is associated with current or future health problems. The association of obesity with hypertension, glucose intolerance, and lipid metabolism disorder is diagnosed as metabolic syndrome since it tends to cause arteriosclerotic diseases. Obesity is important since it is pandemic throughout the earth. In this review we explain the concept and classification of obesity. We discuss the disease basis of obesity and metabolic syndrome, especially from the standpoint of adipotoxicity.


Subject(s)
Obesity , Humans , Metabolic Syndrome/etiology , Obesity/classification
11.
Nihon Rinsho ; 67(2): 404-7, 2009 Feb.
Article in Japanese | MEDLINE | ID: mdl-19202919

ABSTRACT

Obesity is closely associated with development of hypertension. Adipose tissue produces molecules of renin-angiotensin system, which contribute to metabolic as well as cardiovascular disorders that develop in obesity. CASE-J Study demonstrated the usefulness of angiotensin receptor blockade in preventing new onset diabetes in obese hypertensive patients.


Subject(s)
Diabetes Mellitus, Type 2/prevention & control , Hypertension/prevention & control , Obesity/complications , Angiotensin Receptor Antagonists , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Diabetes Mellitus, Type 2/etiology , Humans , Hypertension/etiology
12.
Obes Res Clin Pract ; 3(2): I-II, 2009 May.
Article in English | MEDLINE | ID: mdl-24345559

ABSTRACT

OBJECTIVE: Dysregulation of tissue-specific intracellular glucocorticoid reactivation is implicated in obesity and related metabolic diseases in humans. The ratio of end products of glucocorticoid metabolism in fresh urine sample, tetrahydrocortisol (THF) + allo-tetrahydrocortisol (allo-THF) vs. tetrahydrocortisone (THE), i.e., the urinary ratio is regarded as an index of the systemic balance underlying intracellular glucocorticoid metabolism, where the enzymes, 11ß-hydroxysteroid dehydrogenase type 1 and type 2 as well as 5α- and 5ß-reductase are involved in a tissue-specific manner. METHODS: To explore the clinical implications of the urinary ratio in obesity and related metabolic diseases, the urinary ratio was determined by gas chromatography and mass spectrometry. RESULTS: The urinary ratio was shown to be constant and reproducible in the same individuals. The ratio was found to inversely correlate with BMI (P < 0.01), waist circumference (P < 0.01), and liver transaminase (P < 0.05) in a large cohort of ∼200 Japanese subjects. This finding suggests that the systemic balance underlying intracellular glucocorticoid reactivation was suppressed in obesity and liver dysfunction. Consistent with this notion, the ratio was decreased in patients with non-alcoholic steatohepatitis (P < 0.01). The urinary ratio was not altered in patients with type 2 diabetes on a 2-month mild calorie restriction. In contrast, the ratio was significantly reduced in patients who responded to the anti-diabetic pioglitazone (P < 0.01). CONCLUSION: The present study provides novel evidence that the urinary ratio reflects the facet of adipose tissue and liver function in humans, thereby offering a unique opportunity to evaluate obesity-related diseases.

13.
Metabolism ; 56(12): 1719-28, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17998027

ABSTRACT

A single bout of exercise increases the rate of muscle glucose transport (GT) by both insulin-independent and insulin-dependent mechanisms. The purpose of this study was to determine whether high-fat diet (HFD) feeding interferes with the metabolic activation induced by moderate-intensity endurance exercise. Rats were fed an HFD or control diet (CD) for 4 weeks and then exercised on a treadmill for 1 hour (19 m/min, 15% incline). Insulin-independent GT was markedly higher in soleus muscle dissected immediately after exercise than in muscle dissected from sedentary rats in both dietary groups, but insulin-independent GT was 25% lower in HFD-fed than in CD-fed rats. Insulin-dependent GT in the presence of submaximally effective concentration of insulin (0.9 nmol/L) was also higher in both dietary groups in muscle dissected 2 hours after exercise, but was 25% lower in HFD-fed than in CD-fed rats. Exercise-induced activation of 5'adenosine monophosphate-activated protein kinase, a signaling intermediary leading to insulin-independent GT and regulating insulin sensitivity, was correspondingly blunted in the HFD group. High-fat diet did not affect glucose transporter 4 content or insulin-stimulated Akt phosphorylation. Our findings provide evidence that an HFD impairs the effects of short-term endurance exercise on glucose metabolism and that exercise does not fully compensate for HFD-induced insulin resistance in skeletal muscle. Although the underlying mechanism is unclear, reduced 5'adenosine monophosphate-activated protein kinase activation during exercise may play a role.


Subject(s)
Dietary Fats/administration & dosage , Glucose/metabolism , Insulin Resistance/physiology , Muscle, Skeletal/metabolism , Physical Conditioning, Animal/physiology , Adenylate Kinase/metabolism , Animals , Blotting, Western , Dietary Fats/metabolism , Enzyme Activation , Glucose Transporter Type 4/metabolism , Glycogen/metabolism , Male , Muscle Fibers, Skeletal/enzymology , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/ultrastructure , Muscle, Skeletal/enzymology , Muscle, Skeletal/ultrastructure , Oncogene Protein v-akt/metabolism , Phosphorylation , Rats , Rats, Wistar , Triglycerides/metabolism
14.
Dev Dyn ; 236(10): 2779-91, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17849436

ABSTRACT

Notch signaling regulates cell fate determination in various tissues. We have reported the generation of mice with a pancreas-specific knockout of Rbp-j using Pdx.cre mice. Those mice exhibited premature endocrine and ductal differentiation. We now generated mice in which the Rbp-j gene was inactivated in Ptf1a-expressing cells using Ptf1a.cre mice. The timing of the Cre-mediated deletion in Rbp-j(f/f) Ptf1a.cre mice is 1 day later than that in Rbp-j(f/f) Pdx.cre mice. In Rbp-j(f/f) Ptf1a.cre mouse pancreases, at E13.5, the reduced Hes1 expression was accompanied by reduced epithelial growth, but premature endocrine cell differentiation was minimal. At E15.5, Pdx1 expression was repressed and acinar cell differentiation was reduced, but an increase in acinar cell proliferation was observed during the perinatal period. Our study indicates that, in addition to its role in preventing premature differentiation of early endocrine cells, Rbp-j regulates epithelial growth, Pdx1 expression, and acinar cell differentiation during mid-pancreatic development.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Epithelial Cells/cytology , Pancreas, Exocrine/embryology , Pancreas/cytology , Pancreas/embryology , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Cell Differentiation/genetics , Cell Proliferation , Epithelial Cells/metabolism , Gene Expression Regulation, Developmental , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Immunoglobulin J Recombination Signal Sequence-Binding Protein , Mice , Mice, Knockout , Pancreas/metabolism , Pancreas, Exocrine/cytology , Pancreas, Exocrine/metabolism , Receptors, Notch/genetics , Receptors, Notch/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism
15.
J Biol Chem ; 282(40): 29574-83, 2007 Oct 05.
Article in English | MEDLINE | ID: mdl-17681946

ABSTRACT

Rho-associated kinase (ROCK) regulates reorganization of actin cytoskeleton. During adipogenesis, the structure of filamentous actin is converted from long stress fibers to cortical actin, suggesting that the ROCK is involved in adipogenesis. Two ROCK isoforms have been identified: ROCK-I and ROCK-II. However, pharmacological inhibitors of ROCK cannot distinguish two ROCK isoforms. In the present study, we examined the role of ROCK in adipogenesis and actin cytoskeleton using genetic and pharmacological approaches. Y-27632, which inhibits the activity of both ROCK isoforms, enhanced adipogenesis through the up-regulation of adipogenic transcription factors in 3T3-L1 cells. Furthermore, Y-27632 restored inhibition of adipogenesis by lysophosphatidic acid, which activates Rho. Regarding actin cytoskeleton, Y-27632 disrupted stress fibers in 3T3-L1 preadipocytes. Next, we analyzed adipogenesis of mouse embryonic fibroblasts (MEFs) derived from ROCK-I and ROCK-II knock-out mice, respectively. Adipogenesis of ROCK-II (-/-) MEFs was markedly enhanced compared with wild-type MEFs while that of ROCK-I (-/-) MEFs was not. In contrast to pharmacological approaches, no obvious alteration was found in actin cytoskeleton of ROCK-II (-/-) MEFs compared with wild-type MEFs. In 3T3-L1 cells, knockdown of ROCK-II by RNA interference enhanced the expression of adipogenic transcription factors while that of ROCK-I did not. Moreover, Y-27632 inhibited IRS-1 serine phosphorylation and enhanced Akt phosphorylation in 3T3-L1 preadipocytes. Similarly, Akt phosphorylation in ROCK-II (-/-) MEFs was augmented compared with wild-type MEFs. In conclusion, inhibition of ROCK-II, not ROCK-I, enhances adipogenesis accompanied by the up-regulation of adipogenic transcription factors. Augmentation of insulin signaling may contribute to the enhancement of adipogenesis.


Subject(s)
Adipocytes/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , 3T3-L1 Cells , Actins/metabolism , Adipocytes/drug effects , Adipogenesis/drug effects , Animals , Cytoskeleton/metabolism , Dose-Response Relationship, Drug , Fibroblasts/metabolism , Insulin/metabolism , Mice , Mice, Knockout , Models, Biological , Models, Genetic , Signal Transduction , rho-Associated Kinases
16.
Cell Metab ; 5(5): 395-402, 2007 May.
Article in English | MEDLINE | ID: mdl-17488641

ABSTRACT

Little is known about the role of the central melanocortin system in the control of fuel metabolism in peripheral tissues. Skeletal muscle AMP-activated protein kinase (AMPK) is activated by leptin and serves as a master regulator of fatty acid beta-oxidation. To elucidate an unidentified role of the central melanocortin system in muscle AMPK regulation, we treated conscious, unrestrained mice intracerebroventricularly with the melanocortin agonist MT-II or the antagonist SHU9119. MT-II augmented phosphorylation of AMPK and its target acetyl-CoA carboxylase (ACC) independent of caloric intake. Conversely, AMPK/ACC phosphorylation by leptin was abrogated by the coadministration of SHU9119 or in KKA(y) mice, which centrally express endogenous melanocortin antagonist. Importantly, high-fat-diet-induced attenuation of AMPK/ACC phosphorylation in leptin-overexpressing transgenic mice was not reversed by central leptin but was markedly restored by MT-II. Our data provide evidence for the critical role of the central melanocortin system in the leptin-skeletal muscle AMPK axis and highlight the system as a therapeutic target in leptin resistance.


Subject(s)
Melanocortins/metabolism , Muscle, Skeletal/metabolism , Protein Kinases/metabolism , Signal Transduction/physiology , AMP-Activated Protein Kinase Kinases , Analysis of Variance , Animals , Blotting, Western , Dietary Fats , Leptin/metabolism , Melanocortins/agonists , Melanocortins/antagonists & inhibitors , Melanocyte-Stimulating Hormones/pharmacology , Metallothionein/pharmacology , Mice , Phosphorylation/drug effects
17.
Endocr J ; 54(1): 113-21, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17146148

ABSTRACT

Insulinoma is the most common cause of fasting hypoglycemia resulting from autonomous insulin hypersecretion. A 59-year-old woman who had previously had an insulinoma and had undergone a partial pancreatectomy was admitted to our hospital because of recurrence of hypoglycemia after 27 years. She had two unusual endocrinological features: 1) the serum insulin response to intravenous secretin injection was not impaired, and 2) the serum C-peptide levels and ratios of serum C-peptide to insulin were relatively low. Two pancreatic tumors were readily detectable by computed tomography (CT) and magnetic resonance imaging (MRI). The selective arterial calcium injection (SACI) test showed a hyperinsulinemic response by calcium administration to the gastroduodenal artery. A partial pancreatectomy was done and her hypoglycemia disappeared. Histology revealed that the tumors were composed of monotonous, small round cells that were positive for both insulin and cathepsin B. As previous in vitro studies have shown that C-peptide can be metabolized within human insulinoma cells by proteolytic cleavage by cathepsin B, our patient's low serum C-peptide levels might have been caused by degradation of C-peptide by cathepsin B. According to the data from the literature, the molar ratio of serum C-peptide to insulin is generally decreased in patients with insulinoma than normal subjects. This case highlights the need for careful interpretation of C-peptide levels and the intravenous secretin injection test in the diagnosis of insulinoma.


Subject(s)
C-Peptide/blood , Insulinoma/drug therapy , Pancreatic Neoplasms/drug therapy , Secretin/therapeutic use , Blood Glucose/analysis , Female , Humans , Insulin/blood , Insulinoma/blood , Insulinoma/surgery , Middle Aged , Pancreatic Neoplasms/blood , Pancreatic Neoplasms/surgery
18.
J Clin Endocrinol Metab ; 92(2): 532-41, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17118991

ABSTRACT

BACKGROUND: Lack of leptin is implicated in insulin resistance and other metabolic abnormalities in generalized lipodystrophy; however, the efficacy, safety, and underlying mechanisms of leptin-replacement therapy in patients with generalized lipodystrophy remain unclear. METHODS: Seven Japanese patients with generalized lipodystrophy, two acquired and five congenital type, were treated with the physiological replacement dose of recombinant leptin during an initial 4-month hospitalization followed by outpatient follow-up for up to 36 months. RESULTS: The leptin-replacement therapy with the twice-daily injection dramatically improved fasting glucose (mean +/- SE, 172 +/- 20 to 120 +/- 12 mg/dl, P < 0.05) and triglyceride levels (mean +/- SE, 700 +/- 272 to 260 +/- 98 mg/dl, P < 0.05) within 1 wk. The leptin-replacement therapy reduced insulin resistance evaluated by euglycemic clamp method and augmented insulin secretion at glucose tolerance test with different responses between acquired and congenital types. Improvement of the fatty liver was also observed. The efficacy and safety of the once-daily injection were comparable to those of the twice-daily injection. The leptin-replacement therapy ameliorated macro- and microalbuminuria and showed no deterioration of neuropathy and retinopathy of these patients. The leptin-replacement therapy is beneficial to diabetic complications and lipodystrophic ones. Two patients developed antileptin antibodies but not neutralizing antibodies. The therapy was well tolerated, and its effects were maintained for up to 36 months without any notable adverse effects such as hypoglycemia, high blood pressure, or reduction of bone mineral density. CONCLUSIONS: The present study demonstrates the efficacy and safety of the long-term leptin-replacement therapy and possible mechanisms of leptin actions in patients with generalized lipodystrophy.


Subject(s)
Hormone Replacement Therapy/methods , Leptin/administration & dosage , Lipodystrophy/drug therapy , Adolescent , Adult , Albuminuria/complications , Albuminuria/drug therapy , Blood Glucose/drug effects , Child , Diabetes Complications/complications , Diabetes Complications/drug therapy , Fatty Liver/drug therapy , Female , Follow-Up Studies , Glucose Clamp Technique , Glucose Tolerance Test , Humans , Hyperinsulinism , Injections, Subcutaneous , Insulin Resistance , Leptin/adverse effects , Lipodystrophy/complications , Male , Time Factors , Treatment Outcome , Triglycerides/blood
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