Protein tyrosine phosphatase 1B (PTP1B) and SH2 domain-containing protein tyrosine phosphatase-2 (SHP2) have been shown in mice to regulate metabolism via the central nervous system, but the specific neurons mediating these effects are unknown. Here, we have shown that proopiomelanocortin (POMC) neuronspecific deficiency in PTP1B or SHP2 in mice results in reciprocal effects on weight gain, adiposity, and energy balance induced by high-fat diet. Mice with POMC neuron-specific deletion of the gene encoding PTP1B (referred to herein as POMC-Ptp1b -/-mice) had reduced adiposity, improved leptin sensitivity, and increased energy expenditure compared with wild-type mice, whereas mice with POMC neuron-specific deletion of the gene encoding SHP2 (referred to herein as POMC-Shp2 -/-mice) had elevated adiposity, decreased leptin sensitivity, and reduced energy expenditure. POMC-Ptp1b -/-mice showed substantially improved glucose homeostasis on a high-fat diet, and hyperinsulinemic-euglycemic clamp studies revealed that insulin sensitivity in these mice was improved on a standard chow diet in the absence of any weight difference. In contrast, POMCShp2 -/-mice displayed impaired glucose tolerance only secondary to their increased weight gain. Interestingly, hypothalamic Pomc mRNA and α-melanocyte-stimulating hormone (αMSH) peptide levels were markedly reduced in POMC-Shp2 -/-mice. These studies implicate PTP1B and SHP2 as important components of POMC neuron regulation of energy balance and point to what we believe to be a novel role for SHP2 in the normal function of the melanocortin system. IntroductionObesity has become a major health concern worldwide (1). Currently there are few effective therapies for targeting obesity and its associated comorbidities in humans. The CNS has long been implicated in the control of energy balance, with the hypothalamus playing a key role as an integrator of metabolic information (reviewed in ref. 2). Thus, an important area of obesity research centers on understanding the neural signaling pathways that control energy balance.Within the hypothalamus, first-order neurons in the arcuate nucleus (ARC) respond to circulating adiposity signals, such as insulin and leptin, and project to second-order neurons in the paraventricular nucleus (PVN), the dorsomedial hypothalamus (DMH), and the lateral hypothalamus (LHA) to mediate effects on food intake and energy expenditure (3-7). Two distinct populations of first-order neurons synthesize either agouti-related protein (AgRP) or proopiomelanocortin (POMC) and mediate opposing effects on energy balance (4,8). The POMC precursor is cleaved into biologically active peptides, including α-melanocyte-stimulating hormone (αMSH), which binds to melanocortin-3 and -4 receptors on target second-order neurons (9). The adipocyte-secreted hormone leptin acts in the brain as a catabolic hormone to decrease appetite and increase energy expenditure via simultaneous suppression of AgRP neurons and stimulation of POMC neurons (4, 10, 11).The discovery of leptin init...
ContextImmune checkpoint inhibitors, including anti–programmed cell death-1 (PD-1) antibodies, have become promising treatments for a variety of advanced malignancies. However, these medicines can cause immune-related adverse events (irAEs), including endocrinopathies.ObjectiveThis study examined the incidence of endocrine irAEs induced by nivolumab.Patients and Main Outcome MeasuredSixty-six patients treated with nivolumab at Nagoya University Hospital were prospectively evaluated for pituitary hormones, thyroid function, antithyroid antibodies (Abs), and glucose levels every 6 weeks after the initiation of nivolumab for 24 weeks.ResultsFour out of 66 patients developed destructive thyroiditis, and three patients developed hypothyroidism requiring levothyroxine replacement. The prevalence of positive anti-thyroglobulin Abs (TgAbs) and/or anti–thyroid peroxidase Abs (TPOAbs) at baseline was significantly higher in the group that developed destructive thyroiditis (3/4) compared with the group that did not develop thyroiditis (3/62; P = 0.002). There were no significant differences in other clinical variables between the groups. There were no endocrine irAEs other than destructive thyroiditis during the 24 weeks. The prevalence of TgAbs and/or TPOAbs at baseline was not associated with the development of other irAEs, including pneumonitis, colitis, or skin reactions.ConclusionsOur real-world data showed that destructive thyroiditis was an endocrine irAE that was frequently induced by nivolumab and was significantly associated with positive TgAbs and/or TPOAbs before treatment. Our findings indicate that evaluating these Abs before treatment may help identify patients with a high risk of thyroidal irAEs and may have important clinical benefit.
BackgroundSeveral immune-related adverse events (irAEs) are reported to be associated with therapeutic efficacy of immune checkpoint inhibitors, yet whether pituitary dysfunction, a life-threatening irAE, affects overall survival (OS) in patients with malignancies is unclear. This prospective study examined the association of pituitary dysfunction (pituitary-irAE) with OS of patients with non-small cell lung carcinoma (NSCLC) or malignant melanoma (MM).MethodsA total of 174 patients (NSCLC, 108; MM, 66) treated with ipilimumab, nivolumab, pembrolizumab, or atezolizumab at Nagoya University Hospital were evaluated for OS and the development of pituitary-irAE. Kaplan-Meier curves of OS as a function of the development of pituitary-irAE were produced with the log-rank test as a primary endpoint.ResultsPituitary-irAE was observed in 16 patients (4 (3.7%) with NSCLC, 12 (18.2%) with MM) having two different disease types: hypophysitis with deficiency of multiple anterior pituitary hormones accompanied by pituitary enlargement, and isolated adrenocorticotropic hormone (ACTH) deficiency without pituitary enlargement. Among these patients, 6 developed pituitary-irAE while being treated with ipilimumab (6/25 patients (24.0%) treated with ipilimumab) and 10 developed pituitary-irAE during treatment with nivolumab or pembrolizumab (10/167 (6.0%)). All 16 patients had ACTH deficiency and were treated with physiological doses of hydrocortisone. The development of pituitary-irAE was associated with better OS in patients with NSCLC (not reached vs 441 (95% CI not calculated) days, p<0.05) and MM (885 (95% CI 434 to 1336) vs 298 (95% CI 84 to 512) days, p<0.05).ConclusionsIn our study cohort, the incidence of pituitary-irAE was higher than previously reported and the development of pituitary-irAE predicted better prognosis for both NSCLC and MM when patients were treated with physiological doses of hydrocortisone.Clinical trials registrationUMIN000019024.
Recent studies suggest that the AMP-activated protein kinase (AMPK) signaling in the hypothalamus is the master regulator of energy balance. We reported in previous studies that glucocorticoids play a permissive role in the regulation of orexigenic neuropeptide Y (Npy) gene expression in the arcuate nucleus. In this study, we examined whether any cross talk occurs between glucocorticoids and AMPK signaling in the hypothalamus to regulate Npy as well as agouti-related peptide (Agrp) gene expression in the arcuate nucleus. In the hypothalamic organotypic cultures, the addition to the medium of the AMPK activator, 5-aminoimidazole-4-carboxamide-1-b-d-ribofuranoside, increased phosphorylated AMPK (p-AMPK) as well as phosphorylated acetyl-coenzyme A carboxylase (p-ACC) in the explants, accompanied by significant increases in Npy and Agrp gene expression in the arcuate nucleus. The incubation with dexamethasone (DEX) also activated AMPK signaling in the explants, accompanied by significant increases in Npy and Agrp gene expression in the arcuate nucleus. The addition of the AMPK inhibitor compound C to the medium, which blocked increases of p-AMPK and p-ACC by DEX, significantly attenuated Npy and Agrp gene expression stimulated by DEX. Furthermore, p-AMPK and p-ACC levels in the arcuate nucleus were significantly decreased in adrenalectomized rats compared with sham-operated rats, and a replacement of glucocorticoids reversed the AMPK signaling in adrenalectomized rats. Thus, our data demonstrated that glucocorticoids up-regulate the Npy and Agrp gene expression in the arcuate nucleus through AMPK signaling, suggesting that the activation of the hypothalamic APMK signaling by glucocorticoids might be essential to the energy homeostasis.
IntroductionThe present study aimed to evaluate the effects of flash glucose monitoring (FGM) and conventional self-monitoring of blood glucose (SMBG) on glycemic control in patients with non-insulin-treated type 2 diabetes.Research design and methodsIn this 24-week, multicenter, open-label, randomized (1:1), parallel-group study, patients with non-insulin-treated type 2 diabetes at five hospitals in Japan were randomly assigned to the FGM (n=49) or SMBG (n=51) groups and were provided each device for 12 weeks. The primary outcome was change in glycated hemoglobin (HbA1c) level, and was compared using analysis of covariance model that included baseline values and group as covariates.ResultsForty-eight participants in the FGM group and 45 in the SMBG group completed the study. The mean HbA1c levels were 7.83% (62.1 mmol/mol) in the FGM group and 7.84% (62.2 mmol/mol) in the SMBG group at baseline, and the values were reduced in both FGM (−0.43% (−4.7 mmol/mol), p<0.001) and SMBG groups (−0.30% (−3.3 mmol/mol), p=0.001) at 12 weeks. On the other hand, HbA1c was significantly decreased from baseline values in the FGM group, but not in the SMBG group at 24 weeks (FGM: −0.46% (−5.0 mmol/mol), p<0.001; SMBG: −0.17% (−1.8 mmol/mol), p=0.124); a significant between-group difference was also observed (difference −0.29% (−3.2 mmol/mol), p=0.022). Diabetes Treatment Satisfaction Questionnaire score was significantly improved, and the mean glucose levels, SD of glucose, mean amplitude of glycemic excursions and time in hyperglycemia were significantly decreased in the FGM group compared with the SMBG group.ConclusionsGlycemic control was better with FGM than with SMBG after cessation of glucose monitoring in patients with non-insulin-treated type 2 diabetes.Trial registration numberUMIN000026452, jRCTs041180082.
Highlights d Hypothalamic-pituitary functional units can be generated from 3D-cultured human iPS cells d Maturation of induced pituitary through simultaneous culture with hypothalamic neurons d ACTH secretion ability of induced pituitary is comparable with adult mice d Induced pituitary cells respond to low-glucose stimulation through the CRH-ACTH pathway SUMMARYThe pituitary is a major hormone center that secretes systemic hormones responding to hypothalamusderived-releasing hormones. Previously, we reported the independent pituitary induction and hypothalamic differentiation of human embryonic stem cells (ESCs).Here, a functional hypothalamic-pituitary unit is generated using human induced pluripotent stem (iPS) cells in vitro. The adrenocorticotropic hormone (ACTH) secretion capacity of the induced pituitary reached a comparable level to that of adult mouse pituitary because of the simultaneous maturation with hypothalamic neurons within the same aggregates. Corticotropin-releasing hormone (CRH) from the hypothalamic area regulates ACTH cells similarly to our hypothalamic-pituitary axis. Our induced hypothalamic-pituitary units respond to environmental hypoglycemic condition in vitro, which mimics a lifethreatening situation in vivo, through the CRH-ACTH pathway, and succeed in increasing ACTH secretion. Thus, we generated powerful hybrid organoids by recapitulating hypothalamic-pituitary development, showing autonomous maturation on the basis of interactions between developing tissues.
Background Anti-programmed cell death-1 (PD-1) antibodies can cause thyroid dysfunction. However, no predictive biomarkers enabling stratification of thyroid dysfunction risk have been identified. Methods A total of 209 patients treated with an anti-PD-1 antibody were evaluated for anti-thyroid antibodies at baseline and prospectively for thyroid function every 6 weeks for 24 weeks after treatment initiation, and then observed until the visits stopped. Thyroid ultrasonography was performed if the patient was positive for anti-thyroid antibodies at baseline. Results Of the 209 patients, 19 (9.1%) developed thyroid dysfunction (destructive thyroiditis or hypothyroidism). The cumulative incidence of thyroid dysfunction was significantly higher in patients who were positive vs. negative for anti-thyroid antibodies (15/44 [34.1%] vs. 4/165 [2.4%], p < 0.001). Forty-two patients positive for anti-thyroid antibodies at baseline were divided into two groups according to the presence of an irregular echo pattern. The cumulative incidence of thyroid dysfunction was significantly higher in those with an irregular vs. a regular echo pattern (13/23 [56.5%] vs. 1/19 [5.3%], p = 0.001). None of the patients developed thyroid dysfunction after the initial 24-week period. Conclusions The risk of thyroid dysfunction induced by anti-PD-1 antibodies can be predicted by evaluation of anti-thyroid antibodies and the thyroid echo pattern at baseline. Trial registration UMIN000019024.
Immune-related adverse events induced by anti–programmed cell death–1 antibodies (PD-1-Ab), including destructive thyroiditis (thyroid-irAE), are thought to be caused by activated T cells. However, the T cell subsets that are directly responsible for damaging self-organs remain unclear. To clarify which T cell subsets are involved in the development of thyroid-irAE, a mouse model of thyroid-irAE was analyzed. PD-1-Ab administration 2.5 months after immunization with thyroglobulin caused destructive thyroiditis. Thyroiditis was completely prevented by previous depletion of CD4+ T cells and partially prevented by depleting CD8+ T cells. The frequencies of central and effector memory CD4+ T cell subsets and the secretion of interferon-γ after stimulation with thyroglobulin were increased in the cervical lymph nodes of mice with thyroid-irAE compared with controls. Histopathological analysis revealed infiltration of CD4+ T cells expressing granzyme B in thyroid glands and major histocompatibility complex class II expression on thyrocytes in mice with thyroid-irAE. Adoptive transfer of CD4+ T cells from cervical lymph nodes in mice with thyroid-irAE caused destruction of thyroid follicular architecture in the irradiated recipient mice. Flow cytometric analyses showed that the frequencies of central and effector memory CD4+ T cells expressing the cytotoxic marker CD27 were higher in peripheral blood mononuclear cells collected from patients with thyroid-irAE induced by PD-1-Ab versus those without. These data suggest a critical role for cytotoxic memory CD4+ T cells activated by PD-1-Ab in the pathogenesis of thyroid-irAE.
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