Mixed-Lineage Leukaemia Gene Regulates Glucose-Sensitive Gene Expression and Insulin Secretion in Pancreatic Beta Cells.

The escalating prevalence of diabetes mellitus underscores the need for a comprehensive understanding of pancreatic beta cell function. Interest in glucose effectiveness has prompted the exploration of novel regulatory factors. The myeloid/lymphoid or mixed-lineage leukaemia gene (MLL) is widely recognised for its role in leukemogenesis and nuclear regulatory mechanisms through its histone methyltransferase activity in active chromatin. However, its function within pancreatic endocrine tissues remains elusive. Herein, we unveil a novel role of MLL in glucose metabolism and insulin secretion. MLL knockdown in ßHC-9 pancreatic beta cells diminished insulin secretion in response to glucose loading, paralleled by the downregulation of the glucose-sensitive genes SLC2a1 and SLC2a2. Similar observations were made in MLL heterozygous knockout mice (MLL+/-), which exhibited impaired glucose tolerance and reduced insulin secretion without morphological anomalies in pancreatic endocrine cells. The reduction in insulin secretion was independent of changes in beta cell mass or insulin granule morphology, suggesting the regulatory role of MLL in glucose-sensitive gene expression. The current results suggest that MLL interacts with circadian-related complexes to modulate the expression of glucose transporter genes, thereby regulating glucose sensing and insulin secretion. Our findings shed light on insulin secretion control, providing potential avenues for therapeutics against diabetes.

Resolvin E3 ameliorates high-fat diet-induced insulin resistance via the phosphatidylinositol-3-kinase/Akt signaling pathway in adipocytes.

Obesity-associated type 2 diabetes mellitus is associated with the development of insulin resistance. Among several metabolites, resolvins that are metabolites of eicosapentaenoic acid have been shown to exert insulin-sensitizing effects; however, the role of resolvin E3 (RvE3) in glucose metabolism has not been studied. In this study, the effect of RvE3 on glucose metabolism in mice with high-fat diet-induced obesity and 3T3L1 adipocytes was studied. C57BL/6 mice fed a high-fat diet were administered RvE3, for which insulin tolerance, oral glucose tolerance tests, and the homeostasis model assessment of insulin resistance, were performed. RvE3 treatment significantly improved insulin sensitivity and glucose tolerance and regulated protein kinase B (Akt) phosphorylation in the adipose tissue. Moreover, RvE3 treatment enhanced the insulin-stimulated glucose transporter 4 (Glut4) translocation, glucose uptake, phosphatidylinositol-3-kinase (PI3K) activity, and Akt phosphorylation in 3T3L1 adipocytes, whereas a PI3K inhibitor inhibited the enhanced insulin-stimulated glucose uptake induced by RvE3. These findings indicate that RvE3 likely improves insulin sensitivity, resulting in the upregulation of glucose uptake in adipocytes by activating the PI3K/Akt signaling pathways. Collectively, the findings of this study show that RvE3 may play a role in glucose homeostasis and could be used as a potential therapeutic target for developing treatments for obesity-associated diabetes.

Assessment of factors associated with improved glycemic control after switching from intermittently scanned to real-time continuous glucose monitoring in Japanese patients with type 1 diabetes.

The advantages of real-time continuous glucose monitoring (rtCGM) over intermittently scanned CGM (isCGM) reportedly include lower glycated hemoglobin (HbA1c) levels as well as reduced glycemic variability. However, there have been few studies of the effect of switching from isCGM to rtCGM on glycemic control, as well as the specific factors underlying any observed improvements. To that end, all patients with type 1 diabetes mellitus who used the DEXCOM rtCGM device (Terumo Corporation, Tokyo, Japan) at our institution were reviewed, and 16 individuals with type 1 diabetes who switched from isCGM to rtCGM were investigated. The patients' HbA1c decreased in 75% of the cases (p = 0.02). On the other hand, GMI increased in 75% of the cases (p = 0.01). Intriguingly, the percentage of time below range and coefficient of variation were significantly improved with rtCGM compared to isCGM (2.9% vs. 7.6%, p = 0.016 and 35% vs. 40%, p = 0.0019, respectively). We also found that the discrepancy between HbA1c and GMI among users of isCGM was a key indicator that improved when switching to rtCGM. If discrepancies are observed between HbA1c and GMI when using isCGM, switching to rtCGM should be considered for improving glycemic control.

SFPQ associated with a co-activator for PPARγ, HELZ2, regulates key nuclear factors for adipocyte differentiation.

We recently isolated a novel co-activator of peroxisome proliferator-activated receptor γ, helicase with zinc finger 2 (HELZ2). HELZ2 null mice were resistant to diet-induced obesity and NAFFL/NASH, and HELZ2 was phosphorylated at tyrosine residues. In order to find a factor related to HELZ2, we analyzed products co-immunoprecipitated with phosphorylated HELZ2 by mass spectrometry analyses. We identified proline- and glutamine-rich (SFPQ) as a protein associating with tyrosine-phosphorylated HELZ2. The knockdown of SFPQ in 3T3-L1 cells downregulated mRNA levels of transcription factors including Krox20, Cebpß, and Cebpδ: key factors for early-stage adipocyte differentiation. In addition, knockdown of SFPQ inhibited 3T3-L1 cell differentiation to mature adipocytes. These findings demonstrated that SFPQ associating with HELZ2 is an important novel transcriptional regulator of adipocyte differentiation.

Pitfalls of intermittent continuous glucose monitoring in patients with steroid diabetes.

Only a few studies of continuous glucose monitoring (CGM) in patients with steroid diabetes have been published. Therefore, we investigated all patients with type 2 diabetes (n = 121) and steroid diabetes (n = 40) who used the FreeStyle Libre Pro® device (Abbott Japan) at Gunma University Hospital between 2017 and 2019. Glycated hemoglobin (HbA1c), mean sensor glucose (SG), and glucose management indicator values were similar in both groups. However, the indices for glycemic variabilities, expressed as standard deviations and percent coefficients of variation, were higher in patients with steroid diabetes than in those with type 2 diabetes. The associations between HbA1c, mean SG, and time in range (TIR) when glucose values were 70-180, <70, or >180 mg/dL were assessed using Pearson's product-moment correlation coefficient, which demonstrated good correlations in both patient groups. However, patients with steroid diabetes had a higher SG and lower TIR than did counterparts with type 2 diabetes who had similar HbA1c levels. To examine the effect of prednisolone on CGM data, we divided patients with steroid diabetes into 2 subgroups according to prednisolone dose (≤5 and >5 mg), and found that the dose of this steroid impacted the associations between HbA1c and CGM data, mean SG, and TIR. In summary, our data highlight the importance of cautiously interpreting CGM data and the optimal HbA1c level in patients with steroid diabetes to prevent diabetes-related complications. Further analyses using other CGM devices are necessary to further validate our findings.

Free triiodothyronine /free thyroxine ratio as an index of deiodinase type 1 and 2 activities negatively correlates with casual serum insulin levels in patients with type 2 diabetes mellitus.

Free triiodothyronine/free thyroxine (FT3/FT4) ratio is considered as an index of the activities of iodothyronine deiodinase types 1 and 2 (DIO1 and DIO2, respectively) and is reportedly associated with insulin resistance in euthyroid adults. Euthyroid women with polycystic ovary syndrome accompanied with insulin resistance have lesser deiodinase activities. Correspondingly, the serum insulin level in a fasted condition positively correlates with the FT3/FT4 ratio, and insulin depletion decreases the DIO2 activity in mice. Selected genetic variants in DIO1 are also associated with insulin resistance measures. Therefore, if insulin positively regulates DIO1 and DIO2, the FT3/FT4 ratio should decrease under impaired insulin action, and the casual insulin level and FT3/FT4 ratio should be negatively correlated. To evaluate this hypothesis, we conducted a single-center retrospective study between 2018 and 2021. All participants visited the selected hospitals monthly for type 2 diabetes mellitus treatment and casual plasma glucose and HbA1c level measurements. Furthermore, their casual serum insulin levels were measured annually. Meanwhile, we excluded patients treated with insulin injection. Ultimately, we evaluated 71 patients, which all exhibited euthyroid conditions. The FT3/FT4 ratio was independently associated with thyroid-stimulating hormone, casual plasma glucose, and casual insulin levels. In terms of the regression coefficients of the univariate linear regression analysis, the FT3/FT4 ratio negatively correlated with the casual serum insulin levels. Therefore, the risk of FT3/FT4 ratio underestimation should be considered when diagnosing Graves' disease, which is often accompanied with insulin resistance.

Angiotensin receptor blockers significantly reduce hemoglobin level in patients with type 2 diabetes mellitus not suffered chronic cardiac failure and chronic kidney disease.

Anemia due to angiotensin receptor blocker (ARB) therapy has been previously reported in patients with diabetes mellitus with glomerular filtration rates of <60 mL min-1/1.73 m2. However, whether Japanese patients with type 2 diabetes mellitus (T2DM) receiving ARB therapy for chronic cardiac failure and chronic kidney disease develop reduced hemoglobin (Hb) levels has not been elucidated. Thus, this cross-sectional study was conducted, and Hb levels were compared between patients with T2DM with and without ARB administration. No significant difference in the prescribed proportion of antidiabetic medicines such as biguanide, sodium glucose co-transporter 2 inhibitors, and α-glucosidase inhibitors was found between the group treated with ARBs and the group without ARBs. Thus, we considered that the effects of antidiabetic medicines on the results were minimum. In this study, the Hb levels of patients who received ARBs (13.8 ± 1.7 g/dL) were significantly lower than those of patients without ARBs (14.9 ± 1.35 g/dL) (p = 0.034). The difference between this study and a previous study relies on eGFR levels. Thus, the eGFR levels of the patients in this study and the previous study were above 60 and below 60 mL min-1/1.73 m2, respectively. Despite those differences, both studies showed that the use of ARBs was associated with a decrease in Hb levels in patients with T2DM. Thus, the evaluation of glycated Hb levels should be focused on whether ARBs are prescribed for patients with T2DM.

In patients with type 2 diabetes the presence of Hashimoto's thyroiditis reduces the beneficial effect of dipeptidyl peptidase-4 inhibitor on plasma glucose control.

In this study, we compared the efficacy of a dipeptidyl peptidase-4 inhibitor (DPP4i) to improve glucose control in patients with type 2 diabetes mellitus (T2DM) with or without Hashimoto's thyroiditis (HT). First, we compared the change in glycated hemoglobin (HbA1c) between the hypothyroid condition (before levothyroxine sodium hydrate [LT4] treatment) and euthyroid condition (after LT4 treatment when patients had achieved euthyroidism for at least six months) in patients with T2DM and HT. Next, we compared the change in HbA1c levels before and six months of DPP4i treatment in patients with T2DM with and without HT. In hypothyroid condition the change in HbA1c after six months of DPP4i treatment was 0.13% ± 0.86%. The change in HbA1c levels from when patients first achieved euthyroidism to after six months in the euthyroid condition was 0.26% ± 0.90%. DPP4i efficacy in patients with T2DM and HT was reduced compared to patients with T2DM but without HT (-0.40 ± 0.90 vs. -0.99 ± 0.5, p = 0.0032). These data suggest that hypothyroidism does not impact on DPP4i efficacy. However, the effect of DPP4i in patients with T2DM and HT was reduced compared to that in T2DM patients without HT. An estimation of thyroid function before prescribing DPP4i may be useful tool for predicting the efficacy of DPP4i, allowing the ruling out complications from HT.

The Optimal "Time in Range" and "Time below Range" are Difficult to Coordinate in Patients with Type 1 Diabetes.

Achieving the optimal glucose level time in range (TIR), as recently proposed by the "International Consensus on Time in Range," is challenging. We retrospectively analyzed data from 192 patients, including 58 with type 1 diabetes, using the FreeStyle Libre Pro system. This device was used by physicians for continuous glucose monitoring (CGM) and for making therapeutic decisions based on unbiased data, as the patients were blinded to their blood glucose levels during monitoring. The desired 70% TIR among patients with type 2 diabetes corresponded to an HbA1c of 7.7%. Importantly, however, a 70% TIR for patients with type 1 diabetes corresponded to an HbA1c of 6.9%, which diverged markedly from the HbA1c of 7.9% that corresponded to the desired 4% time below range (TBR). Moreover, these dissociations were observed more in patients with type 1 diabetes with a higher % coefficient of variation (> 36%). Hence, while the TIR is strongly correlated with HbA1c, it is difficult to coordinate with the TBR in Japanese patients with type 1 diabetes. As these metrics (which are critical indicators in clinical practice) are rapidly gaining popularity globally, including in Japan, our data strongly support the cautious use of new CGM metrics such as TIR and TBR/time above range, and emphasize the importance of individualized treatment in achieving the optimal TIR and TBR, especially in patients with type 1 diabetes.

Evaluation of the relationship between glycated hemoglobin A1c and mean glucose levels derived from the professional continuous flash glucose monitoring system.

Previously, we reported that short-term continuous glucose monitoring (CGM) with the professional iPro2© CGM device is a good clinical indicator of glycated hemoglobin (HbA1c) levels. However, there was no significant correlation between CGM and HbA1c levels when HbA1c levels were >8.0%. To further investigate this issue, we performed a similar study using the FreeStyle Libre Pro©, a newer device that does not require glucose calibration and allows patients to be examined for up to 14 days. Fifty-nine patients (68% women, 32% men) were examined. Twenty-eight and 31 patients presented with type 1 and type 2 diabetes, respectively. Clinically assessed HbA1c levels were compared to blood glucose levels determined by the FreeStyle Libre Pro© for up to 14 days (10.7 ± 3.7 days). We found a significant correlation between HbA1c and CGM levels even when HbA1c levels were >8.0%. Additionally, the correlation between HbA1c and average glucose was identified with the modern CGM and was found to deviate substantially from the new suggested formula. More importantly, we found a more robust correlation between HbA1c and CGM levels in patients with type 2 diabetes. Overestimation or underestimation of blood glucose levels through CGM might increase the risks of inappropriate clinical treatment of diabetes patients. Our results indicate the need for proper CGM data interpretation individualized for each patient to better assist the determination of customized treatments for patients.

Assessment of factors that determine the mean absolute relative difference in flash glucose monitoring with reference to plasma glucose levels in Japanese subjects without diabetes.

The Abbott FreeStyle Libre flash glucose monitoring system (FGM) is a recently introduced, but widespread continuous glucose monitoring system. While its mean absolute relative difference (MARD) value indicating its accuracy is acceptable with reference to the self-monitoring of blood glucose (SMBG) levels, few reports have examined the MARD in sensor glucose values of FGM (FGM-SG) with reference to plasma glucose (PG) levels and the factors determining it. We performed oral glucose tolerance tests (OGTTs) in 25 Japanese subjects without diabetes. Parkes error grid analyses showed that FGM-SG with either SMBG or PG levels as a reference met International Organization for Standardization criteria. The MARD in FGM-SG with reference to SMBG levels was 10.9 ± 4.1% during OGTTs. Surprisingly, the MARD in FGM-SG with reference to PG levels was 20.3 ± 10.3% during OGTTs, revealing a discrepancy in the accuracy of FGM-SG compared with that of PG levels; moreover, the MARD showed negative correlations with fasting blood sugar level, homeostasis model assessment insulin resistance index, and body mass index (BMI). Multiple regression analyses revealed that BMI contributed the most to the MARD when FGM-SG and PG level were compared, as lean individuals have a greater MARD regardless of glucose levels. Inaccurate FGM data could potentially increase the risk of inappropriate treatment; consideration of such factors is critical to ensure reliable FGM values.

FAM83G Is a Novel Inducer of Apoptosis.

The family with sequence similarity 83 (FAM83) protein family G (FAM83G) possesses a predicted consensus phosphorylation motif for serine/threonine-protein kinase D1/protein kinase C mu (PKD1/PKCµ) at serine residue 356 (S356). In this study, overexpressed wild-type FAM83G coimmunoprecipitated with PKD1/PKCµ in Chinese hamster ovary (CHO) cells inhibited heat shock protein 27 (HSP27) phosphorylation at S82 and reduced the living cell number. The expression of a FAM83G phosphorylation-resistant mutant (S356A-FAM83G) had no effect on the living cell number or the induction of spontaneous apoptosis. By contrast, the introduction of a synthetic peptide encompassing FAM83G S356 into HCT116 and HepG2 cells decreased HSP27 S15 and S82 phosphorylation and induced spontaneous apoptosis. On the other hand, the introduction of FAM83G phosphorylation-resistant mutant synthesized peptides (S356A-AF-956 and S356A-AG-066) did not reduce the living cell number or induce spontaneous apoptosis. The endogenous expression of HSP27 and FAM83G was apparently greater in HCT116 and HepG2 cells compared with in CHO cells. In various types of lung cancer cell lines, the FAM83G messenger RNA (mRNA) level in non-small lung cancer cells was at a similar level to that in non-cancerous cells. However, the FAM83G mRNA level in the small cell lung cancer cell lines was variable, and the HSP27 mRNA level in FAM83G mRNA-rich types was greater than that in FAM83G mRNA-normal range types. Taken together, these data demonstrate that FAM83G S356 phosphorylation modulates HSP27 phosphorylation and apoptosis regulation and that HSP27 is a counterpart of FAM83G.

Dapagliflozin Inhibits Cell Adhesion to Collagen I and IV and Increases Ectodomain Proteolytic Cleavage of DDR1 by Increasing ADAM10 Activity.

Dapagliflozin, empagliflozin, tofogliflozin, selective inhibitors of sodium-glucose cotransporter 2 (SGLT2), is used clinically to reduce circulation glucose levels in patients with type 2 diabetes mellitus by blocking the reabsorption of glucose by the kidneys. Dapagliflozin is metabolized and inactivated by UGT1A9. Empagliflozin is metabolized and inactivated by UGT1A9 and by other related isoforms UGT2B7, UGT1A3, and UGT1A8. Tofogliflozin is metabolized and inactivated by five different enzymes CYP2C18, CYP3A4, CYP3A5, CYP4A11, and CYP4F3. Dapagliflozin treatment of HCT116 cells, which express SGLT2 but not UGT1A9, results in the loss of cell adhesion, whereas HepG2 cells, which express both SGLT2 and UGT1A9, are resistant to the adhesion-related effects of dapagliflozin. PANC-1 and H1792 cells, which do not express either SGLT2 or UGT1A9, are also resistant to adhesion related effects of dapagliflozin. On the other hand, either empagliflozin or tofogliflozin treatment of HCT116, HepG2, PANC-1, and H1792 cells are resistant to the adhesion-related effects as observed in dapagliflozin treated HCT116 cells. Knockdown of UGT1A9 by shRNA in HepG2 cells increased dapagliflozin sensitivity, whereas the overexpression of UGT1A9 in HCT116 cells protected against dapagliflozin-dependent loos of cell adhesion. Dapagliflozin treatment had no effect on cellular interactions with fibronectin, vitronectin, or laminin, but it induced a loss of interaction with collagen I and IV. In parallel, dapagliflozin treatment reduced protein levels of the full-length discoidin domain receptor I (DDR1), concomitant with appearance of DDR1 cleavage products and ectodomain shedding of DDR1. In line with these observations, unmetabolized dapagliflozin increased ADAM10 activity. Dapagliflozin treatment also significantly reduced Y792 tyrosine phosphorylation of DDR1 leading to decrement of DDR1 function and detachment of cancer cells. Concomitant with these lines of results, we experienced that CEA in patients with colon cancer, which express SGLT2 but not UGT1A9, and type 2 diabetes mellitus treated by dapagliflozin in addition to chemotherapy was decreased (case 1). CEA in patients with colon cancer, which express SGLT2 but not UGT1A9, and type 2 diabetes mellitus was treated by dapagliflozin alone after radiation therapy was decreased but started to rise after cessation of dapagliflozin (case 2). CA19-9 in two of patients with pancreatic cancer and type 2 diabetes mellitus was resistant to the combination therapy of dapagliflozin and chemotherapy (case 3 and 4 respectively). PIVKAII in patients with liver cancer and type 2 diabetes mellitus, and CYFRA in patients with squamous lung cancer and type 2 diabetes mellitus was also resistant the combination therapy of dapagliflozin and chemotherapy (case 5 and 6 respectively). Taken together, these data suggest a potential role for dapagliflozin anticancer therapy against colon cancer cells that express SGLT2, but not UGT1A9.

Differences in the effects of Kenyan, Tanzanian, and Ethiopian coffee intake on interstitial glucose levels measured by FreeStyle Libre: A pilot case study.

BACKGROUND: Although generally considered part of a healthy diet, coffee consumption has been suspected to be associated with elevated epinephrine levels and increasing insulin resistance. OBJECTIVES: We studied the effects of the intake of 3 different types of coffee (Tanzanian, Ethiopian, and Kenyan) on postprandial interstitial glucose levels. METHOD: Interstitial glucose levels were measured every 15 minutes using the FreeStyle Libre glucose monitoring system (Abbott Diabetes Care Ltd, Witney, United Kingdom) in each individual after drinking coffee compared with when not consuming coffee. RESULTS: Unlike Tanzanian and Ethiopian coffees, Kenyan coffee suppressed the increase of postprandial interstitial glucose levels. Kenyan coffee beans contain less anhydrous caffeine and more chlorogenic acid than Tanzanian and Ethiopian coffee beans. These findings may explain the different effects of these coffee types on postprandial interstitial glucose levels. Furthermore, Kenyan coffee beans inhibited α-glucosidase activity, which may partially explain why Kenyan coffee reduces postprandial interstitial glucose levels. CONCLUSIONS: Coffee is widely consumed as a beverage worldwide, and our findings suggest that patients with diabetes mellitus may benefit from drinking Kenyan coffee because of its ability to reduce postprandial interstitial glucose levels. (Curr Ther Res Clin Exp. 2020; 81:XXX-XXX).

Usage of continuous glucose monitoring (CGM) for detecting an unrecognized hypoglycemia and management of glucocorticoid replacement therapy in adult patients with central hypoadrenalism.

Patients with adrenal insufficiency require appropriate glucocorticoid replacement therapy; however, reliable biological parameters for optimizing glucocorticoid supplementation are limited. The physician has to rely primarily on clinical judgment, carefully taking into account signs and symptoms potentially suggestive of over- or under-replacement. We have found that some patients who are viewed as receiving sufficient doses of glucocorticoids occasionally exhibit morning headache or morning discomfort, which may be caused by unrecognized nocturnal hypoglycemia. Our aim in this study was to evaluate the usefulness of continuous glucose monitoring (CGM) for detecting unrecognized hypoglycemia and optimizing glucocorticoid replacement therapy in adult patients with central hypoadrenalism. Six patients with central hypoadrenalism of various etiologies were included in this study. All patients exhibited occasional morning headache or discomfort. We performed CGM to measure plasma glucose levels in all patients, and CGM identified unrecognized hypoglycemia episodes at midnight and early in the morning in five patients (83%). The CGM findings were used to fine-tune the dosing and regimens of glucocorticoid replacement and to re-evaluate glucose levels to avoid further unrecognized hypoglycemic events. This optimization of hydrocortisone supplementation prevented additional nocturnal hypoglycemia incidences in all cases. The addition of L-thyroxine with hydrocortisone continued to provide favorable glycemic control. Occasional symptoms also improved after maintenance in all patients. These findings demonstrated that CGM may represent a powerful tool for identifying unrecognized hypoglycemia and for optimizing supplementary hormones in patients with central hypoadrenalism, thereby improving their quality of life.

Transducin ß-like 1, X-linked and nuclear receptor co-repressor cooperatively augment the ligand-independent stimulation of TRH and TSHß gene promoters by thyroid hormone receptors.

Mutations in TBL1X, a component of the nuclear receptor co-repressor (N-CoR) and silencing mediator of retinoic acid and thyroid hormone receptor co-repressor complexes, have recently been implicated in isolated central hypothyroidism (CeH). However, the mechanisms by which TBL1X mutations affect negative feedback regulation in the hypothalamus-pituitary-thyroid axis remain unclear. N-CoR was previously reported to paradoxically enhance the ligand-independent stimulation of TRH and TSHß gene promoters by thyroid hormone receptors (TR) in cell culture systems. We herein investigated whether TBL1X affects the unliganded TR-mediated stimulation of the promoter activities of genes negatively regulated by T3 in cooperation with N-CoR. In a hypothalamic neuronal cell line, the unliganded TR-mediated stimulation of the TRH gene promoter was significantly enhanced by co-transfected TBL1X, and the co-transfection of TBL1X with N-CoR further enhanced promoter activity. In contrast, the knockdown of endogenous Tbl1x using short interfering RNA significantly attenuated the N-CoR-mediated enhancement of promoter activity in the presence of unliganded TR. The co-transfection of N365Y or Y458C, TBL1X mutants identified in CeH patients, showed impaired co-activation with N-CoR for the ligand-independent stimulation of the TRH promoter by TR. In the absence of T3, similar or impaired enhancement of the TSHß gene promoter by the wild type or TBL1X mutants, respectively, was observed in the presence of co-transfected TR and N-CoR in CV-1 cells. These results suggest that TBL1X is needed for the full activation of TRH and TSHß gene promoters by unliganded TR. Mutations in TBL1X may cause CeH due to the impaired up-regulation of TRH and/or TSHß gene transcription despite low T3 levels.

HBA1C AND MEAN GLUCOSE DERIVED FROM SHORT-TERM CONTINUOUS GLUCOSE MONITORING ASSESSMENT DO NOT CORRELATE IN PATIENTS WITH HBA1C >8.

OBJECTIVE: Optimum therapy for patients with diabetes depends on both acute and long-term changes in plasma glucose, generally assessed by glycated hemoglobin (HbA1c) levels. However, the correlation between HbA1c and circulating glucose has not been fully determined. Therefore, we carefully examined this correlation when glucose levels were assessed by continuous glucose monitoring (CGM). METHODS: Fifty-one patients (70% female, 30% male) were examined; among them were 28 with type 1 diabetes and 23 with type 2 diabetes. Clinically determined HbA1c levels were compared with blood glucose determined by CGM during a short time period. RESULTS: Changes in HbA1c levels up to 8.0% showed a clear and statistically strong correlation (R = 0.6713; P<.0001) with mean blood glucose levels measured by CGM, similar to that observed in the A1c-derived Average Glucose study in which patients were monitored for a longer period. However, we found no statistical correlation (R = 0.0498; P = .83) between HbA1c and CGM-assessed glucose levels in our patient population when HbA1c was >8.0%. CONCLUSION: Short-term CGM appears to be a good clinical indicator of long-term glucose control (HbA1c levels); however, cautions should be taken while interpreting CGM data from patients with HbA1c levels >8.0%. Over- or underestimation of the actual mean glucose from CGM data could potentially increase the risks of inappropriate treatment. As such, our results indicate that a more accurate analysis of CGM data might be useful to adequately tailor clinical treatments. ABBREVIATIONS: ADAG = A1c-Derived Average Glucose CGM = continuous glucose monitoring %CV = percent coefficient of variation HbA1c = glycated hemoglobin.

Characteristics of Japanese aldosterone-producing adenomas with KCNJ5 mutations.

Somatic mutations in KCNJ5 gene have been identified in patients with adrenal aldosterone-producing adenomas (APAs). We previously reported that Japanese patients with APAs had distinct characteristics from patients in Western countries; i.e. they had a high frequency of KCNJ5 mutations and exhibited a frequent association with cortisol co-secretion. Therefore, APAs among Japanese patients may have different features from those in Western countries. We added recent cases, examined 47 cases (43% male) of APAs, including clinicopathological features, KCNJ5 mutations, and the mRNA levels of several steroidogenic enzymes, and compared the results obtained to those reported in other countries. While the prevalence of KCNJ5 mutations is approximately 40% in Western countries, 37 APA cases (78.7%) showed mutations: 26 with p.G151R and 11 with p.L168R. Although a significant gender difference has been reported in the frequency of KCNJ5 mutations in Europe, we did not find any gender difference. However, the phenotypes of Japanese patients with mutations were similar to those of patients in Western countries; patients were younger and had higher plasma aldosterone levels, lower potassium levels, and higher diastolic blood pressure. Reflecting these phenotypes, APAs with mutations had higher CYP11B2 mRNA levels. However, in contrast to APAs in Western countries, Japanese APAs with mutations showed lower CYP11B1, CYP17A1, and CYP11A1 mRNA levels. These findings demonstrated that Japanese APA patients may have distinct features including a higher prevalence of KCNJ5 mutations, no gender difference in the frequency of these mutations, and characteristics similar to the zona glomerulosa.

Nivolumab-induced hypophysitis in a patient with advanced malignant melanoma.

The anti-programmed cell death-1 monoclonal antibody (mab), nivolumab has recently been approved for the treatment of unresectable or metastatic malignant melanoma and non-small-cell lung cancers in Japan. Ipilimumab, an anti-cytotoxic T lymphocyte antigen-4 mab for malignant melanoma that was approved earlier than nivolumab in Western countries, is known to frequently cause endocrine immune-related adverse events such as hypophysitis and thyroid dysfunction. We herein report a patient with advanced melanoma who appeared to develop hypophysitis as a consequence of the inhibition of PD-1 by nivolumab. One week after the 6th administration of nivolumab, the patient developed progressive fatigue and appetite loss. Laboratory data on admission for the 7th administration of nivolumab showed eosinophilia and hyponatremia. Since ACTH and cortisol levels were low, nivolumab was discontinued and a large dose of hydrocortisone (100 mg/d) was promptly administered intravenously. A magnetic resonance imaging scan revealed the mild enlargement of the anterior pituitary gland and thickening of the stalk with homogenous contrast. A detailed assessment of anterior pituitary functions with hypothalamic hormone challenges showed that hormonal secretions other than ACTH and TSH were normal. With a replacement dose of hydrocortisone (20 mg/d), the 7th administration of nivolumab was completed without exacerbating the patient's general condition. The present report provides the first detailed endocrinological presentation of nivolumab-induced hypophysitis showing the enlargement of the pituitary gland and stalk in a malignant melanoma patient in Japan. Oncologists and endocrinologists need to be familiar with potentially life-threatening hypophysitis induced by immune-checkpoint inhibitors.

GNAS mutations in adrenal aldosterone-producing adenomas.

Mutations in GNAS, which encodes Gsα, have been documented in detail, particularly in human pituitary GH-secreting adenomas. Mutations have also recently been reported in adrenal cortisol-producing adenomas (CPAs), in addition to those in the PRKACA gene. However, mutations have not yet been examined in aldosterone-producing adenomas (APAs). Therefore, we herein investigated mutations in the GNAS gene in APAs. Two of the 15 (13%) CPAs with overt Cushing's syndrome and one of the 9 (11%) CPAs with subclinical Cushing's syndrome examined had the somatic mutations, p.R201S and p.R201C in the GNAS gene. We identified mutations in the GNAS gene (p.R201C) in 2 out of the 33 (6%) APAs tested, both of which showed autonomous cortisol secretion, while 24 APAs had mutations in the KCNJ5 gene (18 with p.G151R and 6 with p.L168R). These GNAS and KCNJ5 mutations were mutually exclusive in these adenomas. We herein demonstrated for the first time the presence of GNAS mutations in APAs, as well as in some cortisol-secreting adenomas. Our results suggest that these mutations, in addition to mutations in the KCNJ5 gene and other genes such as ATP1A1, ATP2B3 and CACNA1D, may be responsible for the tumorigenesis of APAs and CPAs with subclinical Cushing's syndrome.