Endocrine journal最新文献

Central congenital hypothyroidism (CH) can occur as an isolated deficiency or as part of combined pituitary hormone deficiency. Unlike primary CH, central CH cannot be detected by newborn screening (NBS) using dry filter paper blood TSH levels, and early diagnosis remains challenging. In this study, the clinical and genetic backgrounds of patients with isolated central CH were determined through a questionnaire-based survey among members of the Japanese Society for Pediatric Endocrinology. The known causes of isolated central CH were studied in 14 patients, including six with previously reported patient data. The results revealed IGSF1 and TBL1X pathogenic variants in nine and one patient, respectively. All six patients with low free thyroxine (FT4) levels detected in NBS carried IGSF1 pathogenic variants. Five patients with isolated central CH diagnosed after 3 months of age were variant-negative, except for one female patient with a heterozygous IGSF1 variant. Two of the four variant-negative patients and a variant-positive patient were diagnosed with pituitary hypoplasia. One and two patients with IGSF1 variant had obesity and intellectual disability, respectively. Left amblyopia was identified in the patient with a TBL1X variant. The study revalidated that IGSF1 variants comprise the most frequent pathogenic variant in patients with isolated central CH in Japan. The neonatal period is the optimal time for the diagnosis of central CH, particularly IGSF1 abnormalities, and the introduction of T4 screening should be considered in the future, taking cost-effectiveness into consideration.

The association between screen time (ST), including that for smartphones, and overweight/obesity in children was examined separately for boys and girls, considering the influence of lifestyle factors. A cross-sectional study was conducted in 2,242 Japanese children (1,278 girls) aged 10-14 years. Overweight/obesity was defined by the International Obesity Task Force. Logistic regression analysis showed that only for girls, total ST (≥4 h), smartphone ST (≥3 h), and non-smartphone ST (≥2 h) were all independently and significantly associated with overweight/obesity compared to <2 h total ST, non-use of smartphones, and <1 h non-smartphone ST. Thus, smartphone ST ≥3 h and non-smartphone ST ≥2 h were additively associated with overweight/obesity in girls only. Girls having smartphone ST ≥3 h and non-smartphone ST ≥2 h were 6.79 times (95% CI: 3.11-14.81) more likely to have overweight/obesity than girls with less usage of both. In girls, when total ST was ≥4 < 5 h or smartphone ST was ≥2 h, the significant association with overweight/obesity disappeared when physical activity was ≥60 min/day and sleep time was ≥8.5 h. In addition, none of these associations was significant in boys. In Japanese girls, smartphone ST, non-smartphone ST, and total ST were all significantly associated with overweight/obesity. To avoid overweight/obesity, it is suggested to keep smartphone ST, non-smartphone ST, and total ST to <3 h, <2 h, and <4 h, respectively, and to engage in sufficient physical activity and sleep time.

Plasma aldosterone concentration (PAC) was routinely measured using radioimmunoassay (RIA); however, the RIA kit was discontinued in March 2021 in Japan. This study examined PAC conversion in adrenal venous sampling (AVS) and AVS criteria when measured using chemiluminescent enzyme immunoassay (CLEIA). PAC of 415 adrenal venous blood samples from AVS (including segmental AVS) of 63 patients with primary aldosteronism was measured using RIA (Spac-S aldosterone kit; Fujirebio Inc.) and CLEIA (Lumipulse Presto Aldosterone; Fujirebio Inc.). PAC of 70 AVS samples was also measured using liquid chromatography-mass spectrometry (LC-MS/MS, ASKA Pharma Medical Co., Ltd.). PAC conversion formulas were determined for each AVS sample assay. PAC measured using CLEIA was significantly correlated with that measured using RIA (correlation coefficient = 0.971). The PAC conversion formula was PAC (CLEIA) = PAC (RIA) × 0.772 – 1,199 pg/mL. The PAC of 14,000 pg/mL in RIA was equivalent to 9,613 pg/mL in CLEIA. PAC measured using CLEIA was also correlated with that measured using LC-MS/MS, and the PAC conversion formula was PAC (CLEIA, pg/mL) = 0.97 × PAC (LC-MS/MS, pg/mL) + 211. The inter-assay coefficient of variability (CV) was 1.1–1.3% and intra-assay CV was 1.0–1.7%, measured using CLEIA. The PAC conversion formula for AVS samples was obtained using CLEIA and RIA, and the conversion formula was different from that for peripheral blood. PAC values measured by CLEIA showed preferable accuracy and high concordance with those measured by LC-MS/MS, even in AVS samples. The study outcomes are useful for interpreting AVS results using non-RIA measurement methods.

Since the 1960s, researchers have recognized an association between elevated plasma branched chain amino acids (BCAA) and metabolic disease, including type 2 diabetes mellitus and obesity, but the cause for it remained poorly understood. Recent advances in metabolomics, advanced imaging techniques, and genetic analyses over the past decade have enabled newfound insights into the mechanism of BCAA metabolic dysregulation across a variety of peripheral tissues and its impact on metabolic disease, suggesting a key role for brown adipose tissue (BAT) in determining BCAA metabolic homeostasis. Previous investigations into BAT have emphasized fatty acids and glucose as substrates for BAT thermogenesis. Here, we address the importance of BAT in systemic BCAA metabolism, driven via the newly identified mitochondrial BCAA carrier (MBC), as well as the impact of BAT-driven BCAA clearance on glucose homeostasis and metabolic disease. The newly identified MBC offers new therapeutic avenues by which BAT activity may be enhanced to improve metabolic and cardiovascular health, as well as other diseases in which increases of circulating BCAA may play a role in pathogenicity.

Activin A promotes the development of endometriotic lesions in a murine model of endometriosis, and the immunohistochemical localization of phosphorylated suppressor of mothers against decapentaplegic homolog 2/3 (pSMAD2/3) complex in endometriotic lesions has been reported. Activin may therefore be involved in the development and proliferation of endometriotic cells via the SMAD signaling pathway. However, few detailed reports exist on SMAD7 expression in endometriosis. The purpose of this study was to investigate the expression of pSMAD2/3 or pSMAD3 and SMAD7 in the orthotopic human endometrium, ovarian endometriosis, and endometriotic lesions in a murine model and the effect of activin A on pSMAD2/3 and SMAD7 expression. We established an endometriosis murine model via the intraperitoneal administration of endometrial tissue and blood from donor mice. Activin A was intraperitoneally administered to the activin group. We immunohistochemically evaluated orthotopic endometria, ovarian endometriotic tissues, and endometriotic lesions in the murine model followed by western blotting. We found that pSMAD3 and SMAD7 were expressed in ovarian endometriosis and orthotopic endometria from patients with and without endometriosis. In the murine model, endometriotic lesions expressed pSMAD2/3 and SMAD7 in the activin and control groups, and higher SMAD7 expression was found in the activin group. To the best of our knowledge, this study is the first to show that SMAD7 expression is upregulated in endometriosis. In conclusion, these results suggest that activin A activates the SMAD signaling pathway and promotes the development of endometriotic lesions, thus identifying SMAD7 as a potential therapeutic target for endometriosis.

The proinsulin-to-C-peptide (PI:C) ratio is an index applied during the early stage of pancreatic β-cell dysfunction. The aim of this study was to identify the characteristics associated with the PI:C ratio to discuss pancreatic β-cell dysfunction progression during the natural course of type 2 diabetes and its relationship with glycemic management. This multicenter, prospective observational study included 272 outpatients with type 2 diabetes. Continuous glucose monitoring was performed and fasting blood samples were collected and analyzed. We identified the clinical factors associated with the PI:C ratio by multiple regression analysis. The mean age of the cohort was 68.0 years, mean hemoglobin A1c 7.1% (54 mmol/mol), and mean body mass index 24.9 kg/m². Multiple regression analysis showed that a prolonged time above the target glucose range (>180 mg/dL) and high body mass index contributed to a high PI:C ratio. However, no associations were found between the PI:C ratio and glucose variability indices. These findings suggested that the PI:C ratio is positively associated with a prolonged hyperglycemic time in type 2 diabetes, whereas its relationship with glucose variability remains unclear.

The main cause of diffuse thyroid goiter is autoimmune chronic thyroiditis, otherwise known as Hashimoto’s thyroiditis. Thyroid hormones play pivotal roles in growth and development during childhood. However, the prevalence of diffuse goiter and the relationships between diffuse goiter, thyroid volume, cysts and nodules, and anthropometric measurements in children are not well known. Among 789,459 participants who participated in thyroid ultrasound examinations, 320,206 participants (male: 161,728; female: 158,478) aged 1–23 years were analyzed. Logistic regression analyses were conducted to calculate the odds ratios of the standard deviation score of body mass index (BMI-SDS), the SDS of bilateral width multiplied thickness area (BWTAR-SDS) as a provisional determination of thyroid volume, and the presence of nodules or cysts for positive diffuse goiter compared with negative diffuse goiter after correction for sex and age. The prevalence of diffuse goiter increased in a female-dominant manner with aging. Compared with the absence of diffuse goiter, the age- and sex-adjusted odds ratios (95% confidence intervals) for BMI-SDS (1 SD), BWTAR-SDS (1 SD), cysts, and nodules were 1.24 (1.21–1.27), 3.21 (3.13–3.29), 0.53 (0.50–0.58), and 1.38 (1.17–1.64), respectively. The odds ratios of nodules for positive diffuse goiter were 4.18 (1.08–16.08), 1.76 (1.01–3.07), 1.80 (1.32–2.45), and 1.34 (1.08–1.67) in the age groups 1–7, 8–11, 12–15, and 16–23 years, respectively. The age-dependent increase in the prevalence of diffuse goiter was independently associated with increased BMI and positive prevalence of nodules in young individuals.

Obesity is a focus of Japanese public health policy, due to Japanese individuals’ high susceptibility to weight-related conditions. In contrast to global definitions, obesity is defined as a body-mass-index (BMI) of ≥25 kg/m² in Japan. Despite public efforts, rates of obesity have not decreased over the past decade. To better understand its societal impact, we examined the economic, quality of life (QoL), and complications burden of obesity in Japan. Electronic databases were searched for English and Japanese-language publications from 2005 to December 2020 reporting on adults with obesity in Japan; other diseases were excluded, with no restriction on intervention. Outcomes of interest included costs or resource use, QoL, risk of complications, and other clinical outcomes. We identified 137 studies, including 19 reporting on economic evidence, eight reporting on QoL, and 115 reporting on the relationship between obesity and the risk of complications or mortality. The studies consistently showed that Japanese adults with obesity (BMI ≥25 kg/m²) are at increased risk of complications vs. normal weight adults. They also confirmed higher total and medical costs, resource use, and hospitalization costs among adults with obesity vs. normal weight adults. In addition, the studies confirmed a considerable impact of obesity on physical and mental aspects of QoL. Overall, this study found that obesity in Japan is associated with a substantial burden. Japanese people are at risk even with BMI ≥25–<30 kg/m², which are generally considered as pre-obese in other countries.

Hyponatremia leads to severe central nervous system disorders and requires immediate treatment in some cases. However, a rapid increase in serum sodium (s-Na) concentration could cause osmotic demyelination syndrome. To achieve a safety hyponatremia treatment, we develop a prediction model of s-Na concentration using a machine learning. Among the 341 and 47 patients admitted to two tertiary hospitals for hyponatremia treatment (s-Na <130 mEq/L), those who were admitted to the general unit with urine sodium <20 mEq/L or treated with desmopressin were excluded. Ultimately, 74 and 15 patients (342 and 146 6-hourly datasets) were included in the learning and validation data, respectively. We trained the prediction model using three regression algorithms for shallow machine learning to predict s-Na every 6 h during treatment with the data of patients with hyponatremia (median s-Na: 112.5 mEq/L; range: 110.0–116.8 mEq/L) from one hospital. The model was validated externally using the data of patients with hyponatremia (median s-Na: 117.0 mEq/L; range: 112.9–120.0 mEq/L) from another hospital. Using 5–7 predictors (water intake, sodium intake, potassium intake, urine volume, s-Na concentration, serum potassium concentration, serum chloride concentration), the support vector regression model showed the best performance overall (root mean square error = 0.05396; R² = 0.92), followed by the linear regression and regression tree models. The predicted s-Na levels, using explainable machine learning algorithms and clinically accessible parameters, correlated well with the actual levels. Thus, our model could be applied to the treatment of hyponatremia in clinical practice.

Subclinical hyperthyroidism (SHyper) is defined as normal levels of free thyroxine (fT4) and free triiodothyronine (fT3) with suppressed levels of TSH. Previous studies have reported the individual pathophysiology of endogenous SHyper patients and athyreotic patients receiving TSH suppression therapy with levothyroxine; however, apparently no studies have compared the two conditions. Five-hundred-forty untreated endogenous SHyper patients and 1,024 patients receiving TSH suppression therapy who underwent total thyroidectomy for papillary thyroid carcinoma were sampled. Thyroid hormone profiles and peripheral indices related to thyrotoxicosis were investigated in endogenous SHyper patients, athyreotic patients receiving TSH suppression therapy, and healthy participants. Endogenous SHyper patients showed significantly higher thyroid hormone levels (fT4 [p < 0.001] and fT3 [p < 0.001]), and peripheral indices showed a significant tendency towards thyrotoxicosis (strong TSH suppression: alkaline phosphatase [ALP, p < 0.001], creatinine [Cre, p < 0.001], pulse rate [p < 0.05]; and mild TSH suppression: Cre [p < 0.05]) than healthy participants. In contrast, athyreotic patients receiving TSH suppression therapy showed a significant tendency towards thyrotoxicosis than healthy participants only when TSH was strongly suppressed (fT3 [p < 0.001] and Cre [p < 0.001]). Endogenous SHyper patients showed significantly higher fT3 levels (p < 0.001) than athyreotic patients receiving TSH suppression therapy; however, there was a significant tendency towards thyrotoxicosis only when TSH was strongly suppressed (ALP [p < 0.05] and pulse rate [p < 0.05]). The effects of endogenous SHyper and TSH suppression therapy on target organ function are different. Although the serum thyroid hormone profile is similar to that of the thyrotoxic state, athyreotic patients receiving TSH suppression therapy with mildly suppressed serum TSH levels are not thyrotoxic.