A Novel Missense MEN1 Mutation in a Sporadic Case of Multiple Endocrine Neoplasia Type 1 Complicated with Papillary Thyroid Carcinoma.

Multiple endocrine neoplasia type 1 (MEN1) is a rare genetic disorder, resulting from MEN1 gene abnormalities, which causes tumors mainly in the endocrine glands. We experienced a sporadic case of MEN1 complicated with papillary thyroid carcinoma (PTC) and found a novel missense mutation in the patient's MEN1 gene. Her older sister, who showed no typical symptom of MEN1, had a history of PTC, suggesting the presence of another genetic factor involved in PTC development. This case suggests the importance of an individual's genetic background in the development of MEN1 complications.

Transit analysis of thyroid antibodies in graves' disease following painless thyroiditis: a case report.

Graves' disease and painless thyroiditis induce hyperthyroidism and are manifestations of an immunological disorder; however, their clinical entities differ. This case report illustrates a possible interrelation between the pathogenesis of these two disorders. A 34-year-old woman presented with palpitations, fatigue, and shortness of breath and was initially diagnosed with painless thyroiditis, which spontaneously normalized within 2 months. Within the euthyroid state, there were atypical alterations in thyroid autoantibodies, namely, activation of the thyroid stimulating hormone receptor antibody and inactivation of thyroid peroxidase and thyroglobulin antibodies. Ten months later, her hyperthyroidism recurred, with this second incidence deemed to be related to Graves' disease. Our patient had two types of painless thyroiditis with no successive hyperthyroidism, followed by Graves' disease, with her clinical manifestation transitioning from painless thyroiditis to Graves' disease over a 20-month period. Future studies are needed to elucidate the mechanisms and relationship between painless thyroiditis and Graves' disease.

A case of vasoactive intestinal peptide-secreting tumor (VIPoma) arising from MEN1 inactivation which recurred 15 years after the initial resection.

Vasoactive intestinal peptide-secreting tumors (VIPomas) are extremely rare functional pancreatic neuroendocrine neoplasms (p-NENs) characterized by watery diarrhea, hypokalemia, and achlorhydria. Here, we report the case of a 51-year-old female patient with VIPoma that recurred after a long-term disease-free interval. This patient had been asymptomatic for approximately 15 years after the initial curative surgery for pancreatic VIPoma, with no metastasis. The patient underwent a second curative surgery for the locally recurrent VIPoma. Whole-exome sequencing of the resected tumor revealed a somatic mutation in MEN1, which is reportedly responsible not only for multiple endocrine neoplasia type 1 (MEN1) syndrome but also sporadic p-NENs. Symptoms were controlled with lanreotide before and after surgery. The patient is alive with no relapse following 14 months after surgery. This case demonstrates the importance of long-term observation of patients with VIPoma.

Serum 25-hydroxycholesterol levels are increased in patients with coronavirus disease 2019.

BACKGROUND: 25-hydroxycholesterol (25HC), produced by cholesterol 25-hydroxylase (CH25H) in macrophages, has been reported to inhibit the replication of viral pathogens such as severe acute respiratory syndrome coronavirus-2. Also, CH25H expression in macrophages is robustly induced by interferons (IFNs). OBJECTIVE: To better understand the serum level increase of 25HC in coronavirus disease 2019 (COVID-19) and how it relates to the clinical picture. METHODS: We measured the serum levels of 25HC and five other oxysterols in 17 hospitalized COVID-19 patients. RESULTS: On admission, 25HC and 27-hydroxycholesterol (27HC) serum levels were elevated; however, 7-ketocholesterol (7KC) levels were lower in patients with COVID-19 than in the healthy controls. There was no significant correlation between 25HC serum levels and disease severity markers, such as interferon-gamma (IFN-γ) and interleukin 6. Dexamethasone effectively suppressed cholesterol 25-hydroxylase (CH25H) mRNA expression in RAW 264.7 cells, a murine leukemia macrophage cell line, with or without lipopolysaccharide or IFNs; therefore, it might mitigate the increasing effects of COVID-19 on the serum levels of 25HC. CONCLUSIONS: Our results highlighted that 25HC could be used as a unique biomarker in severe COVID-19 and a potential therapeutic candidate for detecting the severity of COVID-19 and other infectious diseases.

Cleavages along {110} in bcc iron emit dislocations from the curved crack fronts.

Body-centered-cubic (bcc) transition metals, such as [Formula: see text]-Fe and W, cleave along the {100} plane, even though the surface energy is the lowest along the {110} plane. To unravel the mechanism of this odd response, large-scale atomistic simulations of curved cleavage cracks of [Formula: see text]-Fe were conducted in association with stress intensity factor analyses of straight crack fronts using an interatomic potential created by an artificial neural network technique. The study provides novel findings: Dislocations are emitted from the crack fronts along the {110} cleavage plane, and this phenomenon explains why the {100} plane can be the cleavage plane. However, the simple straight crack-front analyses did not yield the same conclusion. It is suggested that atomistic modeling, at sufficiently large scales to capture the inherent complexities of materials using highly accurate potentials, is necessary to correctly predict the mechanical strength. The method adopted in this study is generally applicable to the cleavage problem of bcc transition metals and alloys.

Sex-specific Association of Primary Aldosteronism With Visceral Adiposity.

Context: The association between primary aldosteronism and obesity, especially its sex difference, remains unknown. Objective: To assess the association for each subtype of primary aldosteronism with obesity parameters including visceral adipose tissue and differences between sexes. Methods: In this case-control study, 4 normotensive controls were selected for each case with primary aldosteronism. Multivariable conditional logistic regression models were used to estimate the association between each type of primary aldosteronism and obesity indicators. We used a random forest to identify which visceral or subcutaneous tissue areas had a closer association with disease status. Results: The study subjects included 42 aldosterone-producing adenoma cases (22 women) and 68 idiopathic hyperaldosteronism cases (42 women). In multivariable conditional logistic regressions, aldosterone-producing adenoma was significantly associated with body mass index only in men (odds ratio [OR] [95% CI)], 4.62 [1.98-10.80] per 2.89 kg/m2) but not in women (OR [95% CI], 1.09 [0.69-1.72] per 3.93 kg/m2) compared with the matched controls, whereas idiopathic hyperaldosteronism was associated with body mass index in both men (OR [95% CI], 3.96 [2.03-7.73] per 3.75 kg/m2) and women (OR [95% CI], 2.65 [1.77-3.96] per 3.85 kg/m2) compared with the matched controls. In random forests, visceral adipose tissue areas were the better predictor of both aldosterone-producing adenoma and idiopathic hyperaldosteronism than subcutaneous adipose tissue. Conclusions: Aldosterone-producing adenoma cases were obese among men, but not among women. Idiopathic hyperaldosteronism cases were obese among both men and women. Visceral adipose tissue may contribute to the pathophysiology of primary aldosteronism.

AAA-ATPase valosin-containing protein binds the transcription factor SREBP1 and promotes its proteolytic activation by rhomboid protease RHBDL4.

Valosin-containing protein (VCP) is a member of AAA-ATPase superfamily involved in various cellular functions. To investigate the pathophysiological role of VCP in metabolic disorders, we generated knock-in mice bearing an A232E mutation in VCP, a known human VCP pathogenic variant. When heterozygous mutant mice (A232E/+) were fed a high-fat diet, we observed that fatty liver was ameliorated and the proteolytic processing of the transcription factor sterol regulatory element-binding protein 1 (SREBP1) was impaired. Further co-immunoprecipitation analysis in wildtype mice revealed interactions of VCP with SREBP1 and a rhomboid protease, RHBDL4, in the liver, and these interactions were attenuated in A232E/+ mice. Consistent with these results, we show that knockdown or chemical inhibition of VCP or RHBDL4 in human hepatocytes impaired the proteolytic processing of SREBP1. Finally, we found that knockdown of E3 ligases such as glycoprotein 78 and HMG-CoA reductase degradation protein 1 disrupted the interaction of VCP with SREBP1 and impaired the proteolytic processing of SREBP1. These results suggest that VCP recognizes ubiquitinylated SREBP1 and recruits it to RHBDL4 to promote its proteolytic processing. The present study reveals a novel proteolytic processing pathway of SREBP1 and may lead to development of new therapeutic strategies to treat fatty liver diseases.

Leptin sensitizing effect of 1,3-butanediol and its potential mechanism.

Leptin is an adipocyte-derived hormone that regulates appetite and energy expenditure via the hypothalamus. Since the majority of obese subjects are leptin resistant, leptin sensitizers, rather than leptin itself, are expected to be anti-obesity drugs. Endoplasmic reticulum (ER) stress in the hypothalamus plays a key role in the pathogenesis of leptin resistance. ATP-deficient cells are vulnerable to ER stress and ATP treatment protects cells against ER stress. Thus, we investigated the therapeutic effects of oral 1,3-butanediol (BD) administration, which increases plasma ß-hydroxybutyrate and hypothalamic ATP concentrations, in diet induced obese (DIO) mice with leptin resistance. BD treatment effectively decreased food intake and body weight in DIO mice. In contrast, BD treatment had no effect in leptin deficient ob/ob mice. Co-administration experiment demonstrated that BD treatment sensitizes leptin action in both DIO and ob/ob mice. We also demonstrated that BD treatment attenuates ER stress and leptin resistance at the hypothalamus level. This is the first report to confirm the leptin sensitizing effect of BD treatment in leptin resistant DIO mice. The present study provides collateral evidence suggesting that the effect of BD treatment is mediated by the elevation of hypothalamic ATP concentration. Ketone bodies and hypothalamic ATP are the potential target for the treatment of obesity and its complications.

Myeloid HMG-CoA Reductase Determines Adipose Tissue Inflammation, Insulin Resistance, and Hepatic Steatosis in Diet-Induced Obese Mice.

Adipose tissue macrophages (ATMs) are involved in the development of insulin resistance in obesity. We have recently shown that myeloid cell-specific reduction of HMG-CoA reductase (Hmgcr m-/m- ), which is the rate-limiting enzyme in cholesterol biosynthesis, protects against atherosclerosis by inhibiting macrophage migration in mice. We hypothesized that ATMs are harder to accumulate in Hmgcr m-/m- mice than in control Hmgcr fl/fl mice in the setting of obesity. To test this hypothesis, we fed Hmgcr m-/m- and Hmgcr fl/fl mice a high-fat diet (HFD) for 24 weeks and compared plasma glucose metabolism as well as insulin signaling and histology between the two groups. Myeloid cell-specific reduction of Hmgcr improved glucose tolerance and insulin sensitivity without altering body weight in the HFD-induced obese mice. The improvement was due to a decrease in the number of ATMs. The ATMs were reduced by decreased recruitment of macrophages as a result of their impaired chemotactic activity. These changes were associated with decreased expression of proinflammatory cytokines in adipose tissues. Myeloid cell-specific reduction of Hmgcr also attenuated hepatic steatosis. In conclusion, reducing myeloid HMGCR may be a promising strategy to improve insulin resistance and hepatic steatosis in obesity.

Clinical characteristics in two patients with partial lipodystrophy and Type A insulin resistance syndrome due to a novel heterozygous missense mutation in the insulin receptor gene.

AIMS: The present report aimed to clarify the clinical characteristics in a girl at the age of 12 and her mother with partial lipodystrophy and Type A insulin resistance syndrome. METHODS: We examined fat distribution in the patients using dual-energy X-ray absorptiometry, magnetic resonance imaging, and computed tomography. We performed genetic analysis to examine the causal gene for lipodystrophy and insulin resistance. RESULTS: Both patients had partial lipodystrophy and a novel heterozygous missense mutation (Asn1137 → Lys1137) in the insulin receptor gene. Because Asn1137 in the catalytic loop is conserved in all protein kinases, this mutation was thought to impair insulin receptor function. By whole-exome sequencing, we found the proband had neither mutations in candidate genes known to be associated with familial partial lipodystrophy nor novel likely candidate causal genes. Taken together, we thought that fat loss in these two patients might be caused by insulin receptor dysfunction. The proband had amenorrhea due to polycystic ovary syndrome. Her menstruation improved, as fat loss was restored during adolescence. This might be caused by improving insulin resistance due to increased levels of leptin and fat mass. CONCLUSIONS: This case might help to understand the mechanisms insulin receptor dysfunction that cause lipodystrophy.

Loss of ACAT1 Attenuates Atherosclerosis Aggravated by Loss of NCEH1 in Bone Marrow-Derived Cells.

AIM: Acyl-CoA cholesterol acyltransferase 1 (ACAT1) esterifies free cholesterol to cholesteryl esters (CE), which are subsequently hydrolyzed by neutral cholesterol ester hydrolase 1 (NCEH1). The elimination of ACAT1 in vitro reduces the amounts of CE accumulated in Nceh1-deficient macrophages. The present study aimed at examining whether the loss of ACAT1 attenuates atherosclerosis which is aggravated by the loss of NCEH1 in vivo. METHODS: Low density lipoprotein receptor (Ldlr)-deficient mice were transplanted with bone marrow from wild-type mice and mice lacking ACAT1, NCEH1, or both. The four types of mice were fed a high-cholesterol diet and, then, were examined for atherosclerosis. RESULTS: The cross-sectional lesion size of the recipients of Nceh1-deficient bone marrow was 1.6-fold larger than that of the wild-type bone marrow. The lesions of the recipients of Nceh1-deficient bone marrow were enriched with MOMA2-positive macrophages compared with the lesions of the recipients of the wild-type bone marrow. The size and the macrophage content of the lesions of the recipients of bone marrow lacking both ACAT1 and NCEH1 were significantly smaller than the recipients of the Nceh1-deficient bone marrow, indicating that the loss of ACAT1 decreases the excess CE in the Nceh1-deficient lesions. The collagen-rich and/or mucin-rich areas and en face lesion size were enlarged in the recipients of the Acat1－/－ bone marrow compared with those of the recipients of the WT bone marrow. CONCLUSION: The loss of ACAT1 in bone marrow-derived cells attenuates atherosclerosis, which is aggravated by the loss of NCEH1, corroborating the in vitro functions of ACAT1 (formation of CE) and NCEH1 (hydrolysis of CE).

Inflammasome Activation Aggravates Cutaneous Xanthomatosis and Atherosclerosis in ACAT1 (Acyl-CoA Cholesterol Acyltransferase 1) Deficiency in Bone Marrow.

Objective- ACAT1 (Acyl-CoA cholesterol acyltransferase 1) esterifies cellular free cholesterol, thereby converting macrophages to cholesteryl ester-laden foam cells in atherosclerotic lesions and cutaneous xanthoma. Paradoxically, however, loss of ACAT1 in bone marrow causes the aggravation of atherosclerosis and the development of severe cutaneous xanthoma in hyperlipidemic mice. Recently, it has been reported that cholesterol crystals activate NLRP3 (NACHT, LRR [leucine-rich repeats], and PYD [pyrin domain] domain-containing protein 3) inflammasomes, thereby contributing to the development of atherosclerosis. The present study aimed to clarify the role of NLRP3 inflammasomes in the worsening of atherosclerosis and cutaneous xanthoma induced by ACAT1 deficiency. Approach and Results- Ldlr-null mice were transplanted with bone marrow from WT (wild type) mice and mice lacking ACAT1, NLRP3, or both. After the 4 types of mice were fed high-cholesterol diets, we compared their atherosclerosis and skin lesions. The mice transplanted with Acat1-null bone marrow developed severe cutaneous xanthoma, which was filled with numerous macrophages and cholesterol clefts and had markedly increased expression of inflammatory cytokines, and increased atherosclerosis. Loss of NLRP3 completely reversed the cutaneous xanthoma, whereas it improved the atherosclerosis only partially. Acat1-null peritoneal macrophages showed enhanced expression of CHOP (C/EBP [CCAAT/enhancer binding protein] homologous protein) and TNF-α (tumor necrosis factor-α) but no evidence of inflammasome activation, after treatment with acetylated LDL (low-density lipoprotein). Conclusions- Elimination of ACAT1 in bone marrow-derived cells aggravates cutaneous xanthoma and atherosclerosis. The development of cutaneous xanthoma is induced mainly via the NLRP3 inflammasome activation.

Impaired adipogenic capacity in induced pluripotent stem cells from lipodystrophic patients with BSCL2 mutations.

OBJECTIVE: Congenital generalized lipodystrophy (CGL) is an autosomal recessive disorder characterized by marked scarcity of adipose tissue, extreme insulin resistance, hypertriglyceridemia, hepatic steatosis and early-onset diabetes. Mutation of the BSCL2/SEIPIN gene causes the most severe form of CGL. The aim of this study was to generate induced pluripotent stem (iPS) cells from patients with CGL harboring BSCL2/SEIPIN mutations. METHODS: Skin biopsies were obtained from two Japanese patients with CGL harboring different nonsense mutations (E189X and R275X) in BSCL2/SEIPIN. The fibroblasts thus obtained were infected with retroviruses encoding OCT4, SOX2, c-MYC, and KLF4. The generated iPS cells were evaluated for pluripotency by examining the expression of pluripotency markers (alkaline phosphatase, SSEA-4, TRA-1-60, and NANOG) and their ability to differentiate to three germ layers in vitro by forming embryoid bodies, and to form teratomas in vivo. Adipogenic capacity of differentiated BSCL2-iPS cells was determined by oil red O and adipose differentiation-related protein (ADRP) staining. Rescue experiments were also performed using stable expression of wild-type BSCL2. A coimmunoprecipitation assay was conducted to investigate the interaction of SEIPIN with ADRP. RESULTS: iPS cells were generated from fibroblasts of the two patients with CGL. Each of the patient-derived iPS (BSCL2-iPS) clones showed all of the hallmarks of pluripotency and could differentiate into derivatives of all three germ layers in vitro by forming embryoid bodies, and form teratomas after injection into mouse testes. BSCL2-iPS cells maintained the mutations in BSCL2 and lacked intact BSCL2. Upon adipogenic differentiation, BSCL2-iPS cells exhibited marked reduction of lipid droplet formation concomitant with diffuse cytoplasmic distribution of ADRP, compared with iPS cells from healthy individuals. Forced expression of BSCL2 not only rescued the lipid accumulation defects, but also restored cytoplasmic punctate localization of ADRP in BSCL2-iPS cells. Coimmunoprecipitation indicated SEIPIN interacted with ADRP. CONCLUSION: BSCL2-iPS cells that recapitulate the lipodystrophic phenotypes in vitro could provide valuable models with which to study the physiology of lipid accumulation and the pathology of human lipodystrophy. We found that BSCL2 defines the localization of ADRP, which has a role in lipid accumulation and adipogenic differentiation.

Hyperleptinemia suppresses aggravation of arthritis of collagen-antibody-induced arthritis in mice.

BACKGROUND: Leptin is an adipocytokine produced by adipocytes and controlling body weight. It is unclear whether leptin works as a proinflammatory or an anti-inflammatory cytokine. We investigated the effects of hyperleptinemia on leptin transgenic (LepTg) mice in terms of cartilage destruction, bone destruction, joint synovitis, and serum cytokine levels by using a mouse model of collagen-antibody-induced arthritis (CAIA). METHODS: CAIA was induced for female age-matched 6- to 8-week-old C57BL/6 J control mice and LepTg mice. Mice were injected intraperitoneally with 5 mg of a combination of monoclonal antibody specific for type II collagen on day 0 and 12.5 mg of lipopolysaccharide (LPS) on day 3. Clinical evaluation of arthritis was monitored for 14 days, and hind paws were examined clinically and histologically. Serum cytokine levels of interleukin (IL)-1ß, IL-6, IL-10, and IL-17 and tumor necrosis factor alpha (TNF-α) were also analyzed on days 0 and 5. Moreover, THP-1 cells, which are human monocytic cell line derived from an acute monocytic leukemia patient, were cultured and differentiated into macrophages. The effects of leptin on messenger RNA (mRNA) expression of IL-6 were examined by real-time quantitative polymerase chain reaction (RT-PCR). RESULTS: Serum leptin concentrations were approximately ninefold higher in LepTg mice (62.0 ± 20.7 ng/ml) than in control mice (7.2 ± 0.5 ng/ml). Severity of clinical paw swelling, arthritis score, synovial hyperplasia, and cartilage damage were suppressed in LepTg mice with CAIA. Although serum cytokine levels of IL-1ß, IL-17, and IL-10 and TNF-α showed no significant changes in two mice, serum levels of IL-6 in LepTg mice were suppressed at day 5. Moreover, in vitro study showed that IL-6 elevation following LPS exposure in THP-1 cells was suppressed with high leptin concentrations. CONCLUSION: Our finding suggests that hyperleptinemia suppress IL-6 responses and progression of joint inflammation. Leptin may play an anti-inflammatory role under hyperleptinemia.

[A Case of Rectal Stenosis For Gastric Cancer Recurrence Effectively Treated with a Colonic Stent].

A man in his 70s underwent distal gastrectomy and D1 dissection with Roux-en-Y reconstruction in March 2009 for advanced gastric cancer with peritoneal metastasis. He was diagnosed with signet-ring cell carcinoma, Stage Ⅳ(T4a, N3a, H0, P1, CY1, M1) and R2. Seventeen cycles of S-1 plus CDDP were administered from April 2009 to December 2010 and 19 cycles of S-1 monotherapy were administered from January 2011 to March 2014. He developed peritoneal recurrence with serum tumor marker elevation in May 2014. Stenosis of the common bile duct, hydronephrosis, and rectal stenosis in Ra-Rs was observed in June 2014. A bile duct stent and a double J catheter was inserted. A colonic stent (NitiTM, 22 mm×6 cm) was also inserted. He could eat after the surgery and was discharged from the hospital. We suggest that a colonic stent is an effective treatment for colon stenosis due to peritoneal metastasis from gastric cancer.

Leptin restores the insulinotropic effect of exenatide in a mouse model of type 2 diabetes with increased adiposity induced by streptozotocin and high-fat diet.

Leptin may reduce pancreatic lipid deposition, which increases with progression of obesity and can impair ß-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 ß-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. We chronically administered leptin (500 µg·kg⁻¹·day⁻¹) and/or exenatide (20 µg·kg⁻¹·day⁻¹) for 2 wk in a mouse model of type 2 diabetes with increased adiposity induced by streptozotocin and high-fat diet (STZ/HFD mice). The STZ/HFD mice exhibited hyperglycemia, overweight, increased pancreatic triglyceride level, and reduced glucose-stimulated insulin secretion (GSIS); moreover, the insulinotropic effect of exenatide was reduced. However, leptin significantly reduced pancreatic triglyceride level, and adding leptin to exenatide (LEP/EX) remarkably enhanced GSIS. These results suggested that the leptin treatment restored the insulinotropic effect of exenatide in the mice. In addition, LEP/EX reduced food intake, body weight, and triglyceride levels in the skeletal muscle and liver, and corrected hyperglycemia to a greater extent than either monotherapy. The pair-feeding experiment indicated that the marked reduction of pancreatic triglyceride level and enhancement of GSIS by LEP/EX occurred via mechanisms other than calorie restriction. These results suggest that leptin treatment may restore the insulinotropic effect of exenatide associated with the reduction of pancreatic lipid deposition in type 2 diabetes with increased adiposity. Combination therapy with leptin and exenatide could be an effective treatment for patients with type 2 diabetes with increased adiposity.

Primary intestinal follicular lymphoma and premature atherosclerosis in a Japanese diabetic patient with atypical familial partial lipodystrophy.

We experienced a case of primary intestinal follicular lymphoma and premature atherosclerosis in a diabetic patient with familial partial lipodystrophy (FPL) that was detected when the patient was evaluated for laparoscopic sleeve gastrectomy (LSG). As FPL is generally considered to be rare, FPL is often underdiagnosed, especially in obese patients. Therefore, the prevalence of FPL is higher than previous estimates. Our case illustrates that clinicians should perform screening for atherosclerosis and malignancy at the preoperative evaluation and may need to perform metabolic surgery earlier to prevent the development of excess truncal fat, complicated diabetes and atherosclerosis in patients with FPL.

In vitro characterization and engraftment of adipocytes derived from human induced pluripotent stem cells and embryonic stem cells.

Human induced pluripotent stem (iPS) and embryonic stem (ES) cells can differentiate into a variety of cell types. We reported on adipogenic potential of human iPS and ES cells in vitro. In the present study, we investigate the survival and maintenance of adipocytes differentiated in vitro from human iPS and ES cells after transplantation. Following adipogenic induction in vitro, the differentiated cells exhibited functional properties of adipocytes such as lipid storage, lipolysis, and insulin responsiveness. Subsequently, Matrigel containing the differentiated human iPS and ES cells was transplanted into the subcutaneous tissue of nude mice. After 1-4 weeks, the cells with adipocyte-like features were observed in transplanted Matrigel by histological analysis. The human origin of the cells, their lipid accumulation, and gene expression of adipocyte markers in transplanted cells were then confirmed, suggesting the presence of adipocytes in transplanted Matrigel. When the relative areas of these cells were calculated by dividing the adipocyte areas by the total Matrigel areas, we found that they peaked at 2 weeks after transplantation, and that the adipocytes persisted at 4 weeks. The present study demonstrates that human iPS and ES cells can differentiate into adipocytes with functional properties and that adipocytes derived from human iPS and ES cells can survive and maintain the differentiated properties of adipocytes for at least 4 weeks after transplantation. Adipocytes derived from human iPS and ES cells thus have the potential to open new avenues for stem cell-based research into metabolic diseases and future therapeutic applications.

GPR119 expression in normal human tissues and islet cell tumors: evidence for its islet-gastrointestinal distribution, expression in pancreatic beta and alpha cells, and involvement in islet function.

OBJECTIVE: GPR119 is reportedly involved in regulating glucose metabolism and food intake in rodents, but little is known about its expression and functional significance in humans. To begin to assess the potential clinical importance of GPR119, the distribution of GPR119 gene expression in humans was examined. MATERIALS/METHODS: Expression of GPR119 mRNA in fresh samples of normal human pancreas (n=19) and pancreatic islets (n=3) and in insulinomas (n=2) and glucagonomas (n=2), all collected at surgery, was compared with the mRNA expression of various receptors highly expressed and operative in human pancreatic islets. RESULTS: GPR119 mRNA was most abundant in the pancreas, followed by the duodenum, stomach, jejunum, ileum and colon. Pancreatic levels of GPR119 mRNA were similar to those of GPR40 mRNA and were higher than those of GLP1R and SUR1 mRNA, which are strongly expressed in human pancreatic islets. Moreover, levels of GPR119 mRNA in pancreatic islets were more than 10 times higher than in adjacent pancreatic tissue, as were levels of GPR40 mRNA. GPR119 mRNA was also abundant in two cases of insulinoma and two cases of glucagonoma, but was undetectable in a pancreatic acinar cell tumor. Similar results were obtained with mouse pancreatic islets, MIN6 insulinoma cells and alpha-TC glucagonoma cells. CONCLUSIONS: The results provide evidence of an islet-gastrointestinal distribution of GPR119, its expression in pancreatic beta and alpha cells, and its possible involvement in islet function. They also provide the basis for a better understanding of the potential clinical importance of GPR119.

Amylin improves the effect of leptin on insulin sensitivity in leptin-resistant diet-induced obese mice.

Leptin enhances insulin sensitivity in addition to reducing food intake and body weight. Recently, amylin, a pancreatic ß-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. Diet-induced obese (DIO) mice were infused with either saline (S), leptin (L; 500 µg·kg⁻¹·day⁻¹), amylin (A; 100 µg·kg⁻¹·day⁻¹), or leptin plus amylin (L/A) for 14 days using osmotic minipumps. Food intake, body weight, metabolic parameters, tissue triglyceride content, and AMP-activated protein kinase (AMPK) activity were examined. Pair-feeding and weight-matched calorie restriction experiments were performed to assess the influence of food intake and body weight reduction. Continuous L/A coadministration significantly reduced food intake, increased energy expenditure, and reduced body weight, whereas administration of L or A alone had no effects. L/A coadministration did not affect blood glucose levels during ad libitum feeding but decreased plasma insulin levels significantly (by 48%), suggesting the enhancement of insulin sensitivity. Insulin tolerance test actually showed the increased effect of insulin in L/A-treated mice. In addition, L/A coadministration significantly decreased tissue triglyceride content and increased AMPKα2 activity in skeletal muscle (by 67%). L/A coadministration enhanced insulin sensitivity more than pair-feeding and weight-matched calorie restriction. In conclusion, this study demonstrates the beneficial effect of L/A coadministration on glucose and lipid metabolism in DIO mice, indicating the possible clinical usefulness of L/A coadministration as a new antidiabetic treatment in obesity-associated diabetes.