High prevalence of copy number variations in the Japanese participants with suspected MODY.

Maturity-Onset Diabetes of the Young (MODY) is a diabetes mellitus subtype caused by a single gene. The detection rate of the responsible gene is 27% in the United Kingdom, indicating that the causative gene remains unknown in the majority of clinically diagnosed MODY cases. To improve the detection rate, we applied comprehensive genetic testing using whole exome sequencing (WES) followed by Multiplex Ligation-dependent Probe Amplification (MLPA) and functional analyses. Twenty-one unrelated Japanese participants with MODY were enrolled in the study. To detect copy number variations (CNVs), WES was performed first, followed by MLPA analysis for participants who were negative on the basis of WES. Undetermined variants were analyzed according to their functional properties. WES identified 7 pathogenic and 3 novel likely pathogenic variants in the 21 participants. Functional analyses revealed that 1 in 3 variants was pathogenic. MLPA analysis applied to the remaining 13 undetermined samples identified 4 cases with pathogenic CNVs: 3 in HNF4A and 1 in HNF1B. Pathogenic variants were identified in 12 participants (12/21, 57.1%) - relatively high rate reported to date. Notably, one-third of the participants had CNVs in HNF4A or HNF1B, indicating a limitation of WES-only screening.

Analysis of five cases showing false-high Hemoglobin A1c due to reduced catalase activity.

We encountered five cases that exhibited false-high Hemoglobin A1c (HbA1c) levels when samples were examined using the enzyme-based NORUDIA N HbA1c kit. HbA1c levels were higher than those obtained using other methods, such as HPLC, immune-based methods, and other enzyme-based kits. This kit produced inaccurate results for HbA1c when residual peroxides were present in samples. The addition of peroxidase solution restored false-high HbA1c levels in the five cases, indicating that reduced catalase activity was responsible for these values because catalase eliminates peroxide. Catalase activity and gene mutations were examined in the five cases and an immunohistological analysis was performed to assess the expression of catalase. Cases #1 and 2 were diagnosed as acatalasemia and cases #3, 4, and 5 as hypocatalasemia based on compound heterozygous SNP and heterozygous splicing mutations in the catalase gene. Therefore, impaired catalase activity was responsible for false-high HbA1c levels measured by the NORUDIA N HbA1c kit.

Analysis of serum levels and DNA methylation of fibroblast growth factor 21 using peripheral blood-derived genomes in patients with obesity.

Fibroblast growth factor (FGF) 21, a hormone produced by the liver, improves glucose and lipid metabolism. We recently demonstrated that the FGF21 gene (Fgf21) underwent DNA demethylation in the mouse liver via peroxisome proliferator-activated receptor (PPAR) α during the fetal to lactation periods. Furthermore, we found that the DNA methylation state of Fgf21 was involved in obesity in adult animals. In the present study, we analyzed the DNA methylation state of the FGF21 gene (FGF21) in obese patients using genomic DNA extracted from human monocytes and macrophages and investigated the pathophysiological significance of the FGF21 expression response to pemafibrate (PM), a PPARα ligand. We examined 67 patients with obesity stratified into in- and outpatient cohorts. A positive correlation was observed between serum FGF21 levels and triglyceride (TG) levels before PM administration. However, changes in serum FGF21 levels following PM administration did not correlate with the FGF21 DNA methylation rate, except at one CpG site. The body mass index (BMI) and serum TG levels positively correlated with the FGF21 DNA methylation rate, particularly at different CpG positions. A negative correlation was observed between absolute changes in serum FGF21 levels and the ratio of change in serum TG levels after PM administration. Collectively, these results indicate the potential of FGF21 DNA methylation as a surrogate indicator of BMI and serum TG levels, while absolute changes in serum FGF21 levels after PM administration may offer prognostic insights into the efficacy of reducing serum TG levels through PM administration.

Impact of coronavirus disease 2019 on medical practice in endocrine and metabolic diseases in Japan: a nationwide surveillance study conducted by the Japan Endocrine Society.

We investigated the impact of the Coronavirus disease 2019 (COVID-19) pandemic on the management of endocrine and metabolic disorders in Japan. We conducted a cross-sectional nationwide questionnaire survey targeting board-certified endocrinologists under the auspices of the Japan Endocrine Society. The questionnaire consisted of multiple-choice questions and open-ended responses. Out of approximately 2,700 specialists, 528 (19.5%) opted to participate, suggesting a high level of interest in COVID-19 management among endocrinologists. The study found that almost half of participants had encountered cases of endocrine and metabolic disorders following COVID-19 infection or vaccination. Conditions related to thyroid diseases, glucose metabolism disorders/diabetes, and hypothalamic-pituitary disorders were particularly prevalent. Diabetes and obesity were identified as having high rates of severe cases or fatalities due to COVID-19. The study also highlighted challenges in routine diagnosis and treatment, emphasizing the potential benefits of combining remote consultations with in-person visits to optimize the frequency of examinations and check-ups during infectious disease outbreak which disrupts access to healthcare providers. The insights obtained from this survey are expected to contribute to ensuring appropriate healthcare provision for patients with endocrine and metabolic disorders by using flexible consultation formats, particularly even in the conditions where medical access may be limited due to future outbreaks of emerging or re-emerging infectious diseases.

Differences in metabolic characteristics between Metabolically Healthy Obesity (MHO) and Metabolically Unhealthy Obesity (MUO) in weight reduction therapy.

Metabolically Healthy Obesity (MHO) is generally recognized as the absence of any metabolic disorders and cardiovascular diseases, including type 2 diabetes, dyslipidemia, and hypertension, in obese individuals; however, it is not clearly defined. Therefore, the present study investigated differences in metabolic characteristics between individuals with MHO and Metabolically Unhealthy Obesity (MUO) during weight reduction therapy. The key factors defining MHO and the importance of weight reduction therapy for MHO were also examined. Cohort data from the Japan Obesity and Metabolic Syndrome (JOMS) study were analyzed. Subjects were divided into the MHO (n = 25) and MUO (n = 120) groups. Prior to weight reduction therapy, serum adiponectin levels were significantly higher in the MHO group than in the MUO group. Serum adiponectin levels also negatively correlated with the area of subcutaneous adipose tissue (SAT) and Homeostasis model assessment (HOMA)-R in the MHO group, but not in the MUO group. Collectively, the present results suggest the importance of adiponectin for maintaining metabolic homeostasis in the MHO group. On the other hand, no significant differences were observed in inflammatory markers between the MHO and MUO groups, suggesting the presence of chronic inflammation in both groups. Furthermore, a positive correlation was noted between changes in serum cystatin C levels and waist circumference in the MHO group, which indicated that despite the absence of metabolic disorders, the MHO group exhibited anti-inflammatory responses during weight reduction therapy. These results underscore the significance of weight reduction even for individuals with MHO.

Update on subclinical thyroid dysfunction.

Subclinical thyroid dysfunction is defined by serum thyroid-stimulating hormone (TSH) levels either greater or less than the reference range with normal thyroxine (T4) concentrations, and consists of subclinical hypothyroidism (SCH) and subclinical hyperthyroidism (SCHyper). For the proper diagnosis of SCH, it is most important to be able to correctly evaluate the serum TSH levels, which have numerous unique characteristics. We also need to be versed in TSH harmonization, which was recently launched world-wide. In this review, we will attempt to determine the best clinical approaches to the treatment of subclinical thyroid dysfunction based on recent guidelines published from several countries and novel findings of several recent large-scale clinical studies.

Serum thyroid-stimulating hormone receptor antibody levels and thyroid dysfunction after hysterosalpingography: a case-control study.

OBJECTIVE: Hysterosalpingography (HSG) performed with an iodine contrast media can cause thyroid dysfunction, including thyrotoxicosis and hypothyroidism. We investigated the association between the serum levels of thyroid-stimulating hormone receptor antibody (TRAb), an indicator of Graves' disease, and abnormal thyroid function after performing HSG. METHODS: The screening of TRAb was conducted in 362 patients who first visited the Tawara IVF Clinic between April and September 2018. The association between TRAb levels and the effects of HSG examinations on thyroid function were evaluated. RESULTS: Of the 362 patients, 2 (0.55%) had high levels (>2.0 IU/L) of TRAb, whereas 18 (5.0%) had intermediate TRAb levels, ranging from 0.3 to 1.9 IU/L. Of the 98 women (including 7 of the 18 women with TRAb level 0.3-1.9 IU/L, and 91 of the 342 women with TRAb level <0.3 IU/L) who had undergone HSG, two women developed overt thyrotoxicosis after HSG, and the frequency was significantly higher (p = .0044) in the group with intermediate levels of TRAb (28.6%, 2 of 7) than that in the group with low TRAb levels (<0.3 IU/L; 0.0%, 0 of 91). CONCLUSIONS: These findings indicate that increased serum levels of TRAb are significantly associated with the development of thyrotoxicosis after HSG.

A case of generalized lipodystrophy-associated progeroid syndrome treated by leptin replacement with short and long-term monitoring of the metabolic and endocrine profiles.

We herein report a case of a 28-year-old man with generalized lipodystrophy-associated progeroid syndrome treated by leptin replacement. He showed symptoms of generalized lipodystrophy around onset of puberty. His body mass index was 11.9 kg/m2, and he had a short stature, birdlike facies, dental crowding due to micrognathia, partial graying and loss of hair, and a high-pitched voice, all of which are typical features of the progeroid syndrome. Laboratory examinations and abdominal ultrasonography revealed diabetes mellitus, insulin-resistance, dyslipidemia, decreased serum leptin levels (2.2 ng/mL), elevated serum hepatobiliary enzyme levels and fatty liver. Whole exome sequencing revealed de novo heterozygous LMNA p.T10I mutation, indicating generalized lipodystrophy-associated progeroid syndrome, which is a newly identified subtype of atypical progeroid syndrome characterized by severe metabolic abnormalities. Daily injection of metreleptin [1.2 mg (0.04 mg/kg)/day] was started. Metreleptin treatment significantly improved his diabetes from HbA1c 11.0% to 5.4% in six months. It also elevated serum testosterone levels. Elevated serum testosterone levels persisted even 1 year after the initiation of metreleptin treatment. To the best of our knowledge, this is the first Japanese case report of generalized lipodystrophy-associated progeroid syndrome. Furthermore, we evaluated short and long-term effectiveness of leptin replacement on generalized lipodystrophy by monitoring metabolic and endocrine profiles.

Clinical outcomes of 20 Japanese patients with insulinoma treated with diazoxide.

Diazoxide is recognized as an effective medical treatment for insulinoma. However, due to its adverse effects, such as fluid retention, it is sometimes difficult to employ diazoxide at an effective dose in clinical practice. This study aimed to clarify the clinical factors, which may affect efficacy and safety of the diazoxide treatment. We retrospectively evaluated the medical records of 20 patients with insulinoma including 4 malignant cases. The patients were divided into two groups according to the presence or absence of favorable outcomes or adverse effects, and the clinical features of both groups were compared. Diazoxide was effective and ineffective in each 9 patients, respectively. In other 2 cases, the efficacy could not be determined. In the effective group, all patients had benign insulinoma. Additionally, the tumor size determined by imaging test was tended to smaller than the ineffective group but not statistically significant when malignant cases were excluded (p = 0.065). Fluid retention was observed more frequently in females than in males (p = 0.025). Five patients displayed unacceptable thrombocytopenia within a few weeks after the administration of diazoxide. In these patients, the diazoxide dose was significantly higher than that in the other patients [400 mg/day (250-500 mg/day) vs. 225 mg/day (50-425 mg/day), p = 0.027]. These findings may be informative in determining the indication and dose of diazoxide against insulinoma. In addition, a careful evaluation of platelet count would be required for a few weeks after the initiation of diazoxide treatment.

Dipeptidyl peptidase 4 inhibitors attenuates the decline of skeletal muscle mass in patients with type 2 diabetes.

BACKGROUND: Activation of dipeptidyl peptidase 4 has been reported to be associated with impairment of insulin signalling in skeletal muscle, presumably leading to loss of muscle function. This study was aimed to investigate whether the use of dipeptidyl peptidase 4 inhibitors (DPP4i) could attenuate the progressive loss of muscle mass in patients with type 2 diabetes. METHODS: A total 105 patients with type 2 diabetes (mean age 62 ± 12 years; 39% female) were studied in this retrospective observational study. To reduce the bias due to confounding variables, propensity-score matching analysis was performed. Change in skeletal muscle index measured by the whole body dual-energy X-ray absorptiometry at 1-year follow-up was evaluated. One-year changes in visceral and subcutaneous fat area and liver attenuation index were also determined by abdominal computed tomography. RESULTS: Overall, 37 of 105 (35.2%) patients were treated with DPP4i. The estimated change in skeletal muscle index in patients with DPP4i was significantly higher than that in patients without (0.05 ± 0.06 vs -0.10 ± 0.04 kg, P = .046). In a propensity-matched population (N = 48), the same finding was observed (0.04 ± 0.03 in DPP4i versus -0.12 ± 0.03 kg in non-DPP4i, P = .033). There were no significant differences in changes of visceral and subcutaneous fat area and liver attenuation index between patients with DPP4i and those without. CONCLUSIONS: Our data suggest the potential of DPP4i to prevent the progressive loss of muscle mass with ageing in patients with type 2 diabetes.

False-positive TSH receptor antibody-a pitfall of third-generation TSH receptor antibody measurements in neonates.

Maternal Graves' disease (GD) during pregnancy may influence thyroid function in fetuses. Neonates born to mothers with high serum TSH receptor antibody (TRAb) levels have been reported to develop 'neonatal GD'. Therefore, evaluations of serum thyroid hormone and TRAb levels in neonates upon birth are crucial for a prompt diagnosis. At delivery, we measured TRAb with third-generation TRAb test using an M22 human monoclonal antibody in neonates by collecting umbilical cord blood in a blood collection tube with lithium-heparin, which provides a whole blood/plasma sample. In recent years, we have encountered positive TRAb levels (more than 2.0 IU/L) in nineteen neonates born to mothers with GD whose thyroid hormone levels were almost within the reference range and serum TRAb levels were less than 10 IU/L. All the neonates with positive TRAb levels did not exhibit thyrotoxicosis. However, when we measured TRAb levels with serum sample in six out of the nineteen cases, their serum TRAb levels were all negative, suggesting a discrepancy of TRAb levels between in lithium-heparin plasma from umbilical cord blood and serum. Moreover, this discrepancy was observed in neonates born to euthyroid mothers, adult active GD patients and healthy volunteers. Since lithium-heparin plasma from umbilical cord blood is widely used in laboratory tests at delivery, we may encounter 'false-positive' TRAb, which may, in turn, lead to a misdiagnosis of neonatal GD. This is a pitfall of third-generation TRAb measurements in neonates, particularly at delivery, and needs to be considered by obstetricians and neonatologists.

A case of TSH-secreting pituitary adenoma with cyclic fluctuations in serum TSH levels.

A 29-year-old man was referred to our department due to adrenal insufficiency with the inappropriate secretion of TSH (SITSH). Magnetic resonance imaging revealed a pituitary tumor. A weak TSH response in the TRH test, elevated sex hormone binding globulin (SHBG) levels, and the absence of a family medical history of SITSH or TRß gene mutations supported the diagnosis of TSH-secreting pituitary adenoma (TSHoma). However, complete TSH suppression and a blunted cholesterol response in the T3 suppression test as well as normal glycoprotein α-subunit (α-GSU) levels were not compatible with TSHoma. Since TSH, FT3, and FT4 spontaneously returned to normal ranges after admission, he was discharged. One month after his discharge, thyrotoxicosis with elevated serum TSH levels relapsed. After admission, his serum TSH levels returned to within the normal range. After his discharge from the second admission, his serum TSH levels fluctuated in accordance with serum FT3 and FT4 levels and symptoms, such as palpitations. Ten months after his discharge, he was admitted to our department again due to adrenal insufficiency and thyrotoxicosis with elevated serum TSH levels, suggesting cyclic SITSH. Although resistance to thyroid hormone (RTH) was not completely excluded, the pituitary tumor was removed by transsphenoidal surgery (TSS). A pathological diagnosis confirmed TSHoma. We herein report a case of TSHoma in which serum TSH, FT3, and FT4 levels fluctuated periodically. To the best of our knowledge, this is the first case report of "cyclic TSHoma", which needs to be considered when making a differential diagnosis of SITSH.

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.

Epigenetic Switching and Neonatal Nutritional Environment.

The hepatic metabolic function changes sequentially during early life in mammals to adapt to the drastic changes in the nutritional environment. Accordingly, hepatic fatty acid ß-oxidation is activated after birth to produce energy from breast milk lipids. De novo lipogenesis is induced upon the onset of oral intake, when the major nutritional source switches to carbohydrate. However, how a particular metabolic pathway is activated during the liver maturation is poorly understood. We found that the expression of glycerol-3-phosphate acyltransferase 1 (GPAT1), a rate-limiting enzyme of de novo hepatic lipogenesis, is epigenetically regulated in the mouse liver by DNA methylation. In the neonatal liver, DNA methylation of the GPAT1 gene (Gpam) promoter, which is likely to be induced by DNA methyltransferase (Dnmt) 3b, inhibited the recruitment of sterol regulatory element-binding protein-1c (SREBP-1c), whereas in the adult, decreased DNA methylation resulted in active chromatin conformation, allowing the recruitment of SREBP-1c. Maternal nutritional environment affects the DNA methylation status in the Gpam promoter, GPAT1 expression, and triglyceride content in the liver of the offspring. We also found DNA demethylation and increased mRNA expression of the fatty acid ß-oxidation genes in the postnatal mouse liver. The DNA demethylation is specifically induced in the lactation period. Analysis of mice deficient in the nuclear receptor peroxisome proliferator-activated receptor α (PPARα) and maternal administration of a PPARα ligand during the gestation and lactation periods reveals that the DNA demethylation is PPARα-dependent. These findings indicate the gene- and lifestage-specific DNA demethylation of a particular metabolic pathway in the neonatal liver to adapt the marked changes in nutritional environment in early life.

Luseogliflozin reduces epicardial fat accumulation in patients with type 2 diabetes: a pilot study.

BACKGROUND: Accumulation of epicardial fat (EF) is associated with increased cardio-metabolic risks and coronary events, independently of traditional cardiovascular risk factors. Therefore, the reduction of EF volume (EFV) may be associated with reduced cardio-metabolic risks and future cardiovascular events. Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce body fat including visceral fat and cardiovascular events in patients with type 2 diabetes. However, it has still been unknown whether SGLT2 inhibitors can reduce EFV. METHODS: Type 2 diabetic patients with HbA1c 6.5-9.0% and body mass index (BMI, kg/m2) ≥25.0 were enrolled in this single arm pilot study. Participants were administered luseogliflozin 2.5 mg daily and the dosage was tolerated to be increased up to 5.0 mg daily. EFV [median (interquartile range), cm3] was measured by magnetic resonance imaging. Primary endpoint was the decrease in EFV at 12 weeks. Visceral fat area (VFA, cm2) and liver attenuation index (LAI) measured by the abdominal computed tomography, and skeletal muscle index (SMI) and body fat (%) measured by the whole body dual-energy X-ray absorptiometry were also determined at baseline and at 12 weeks. RESULTS: Nineteen patients (mean age: 55 ± 12 years; 26% female) completed this study. Luseogliflozin treatment significantly reduced EFV at 12 weeks [117 (96-136) to 111 (88-134), p = 0.048]. The body weight, BMI, systolic and diastolic blood pressure, HbA1c, fasting plasma glucose, insulin, homeostasis model assessment-insulin resistance (HOMA-IR), triglycerides, SMI, and body fat were significantly reduced by luseogliflozin at 12 weeks. The reduction of EFV was significantly correlated with the reduction of C-reactive protein (r = 0.493, p = 0.019). Neither VFA nor LAI were significantly reduced by the luseogliflozin treatment. No severe adverse events were observed. CONCLUSIONS: Our data suggest that luseogliflozin could reduce the EFV in parallel with the improvement of systemic micro-inflammation and the reduction of body weight in Japanese patients with type 2 diabetes. The reduction of muscle mass after the administration of SGLT2 inhibitors may require a particular attention. Trial registration umin.ac.jp, UMIN000019072.

Insulin Treatment Attenuates Decline of Muscle Mass in Japanese Patients with Type 2 Diabetes.

Sarcopenia is defined as an age-related loss of skeletal muscle mass and strength, and is a major cause of disability and mobility limitations. Recent studies have demonstrated that type 2 diabetes and insulin signaling deficiencies contribute to the progression of sarcopenia, suggesting that a sufficient supply of insulin to the skeletal muscles may be important for the maintenance of muscle function; however, little has been reported regarding whether insulin treatment can protect against sarcopenia. We conducted a retrospective observational study to examine the impact of insulin treatment on the muscle mass of patients with type 2 diabetes. A total of 312 patients (mean age: 64 ± 11 years; 40.8% female; 27.6% treated with insulin) were studied in this retrospective observational study. Skeletal muscle index (SMI) and grip strength (kg) were used to assess sarcopenia. The prevalence of sarcopenia was 18.0%. Insulin treatment was shown to be protective against the annual decline of SMI (standardized ß 0.195; p = 0.025) even after adjusting for covariates, including age, gender, duration of diabetes, and body mass index. In a cohort matched by propensity scores, insulin treatment significantly increased the 1-year change in SMI (mean ± SE) compared with non-insulin-treated group (2.40 ± 0.98% vs. -0.43 ± 0.98%; p = 0.050). Our data suggest that insulin treatment could attenuate the progression of sarcopenia in patients with type 2 diabetes.

Reduction of visceral fat by liraglutide is associated with ameliorations of hepatic steatosis, albuminuria, and micro-inflammation in type 2 diabetic patients with insulin treatment: a randomized control trial.

Liraglutide, an analogue of human glucagon-like peptide 1, reduces cardiovascular events in patients with type 2 diabetes; however, it has still been unknown by which mechanisms liraglutide could reduce cardiovascular events. Type 2 diabetic patients with insulin treatment were enrolled in this randomized, open-label, comparative study. Participants were randomly assigned to liraglutide plus insulin (liraglutide group) and insulin treatment (control group) at 1:1 allocation. Primary endpoint was the change in viscera fat are (VFA, cm2) at 24 weeks. Liver attenuation index (LAI) measured by abdominal computed tomography, urinary albumin-to-creatinine ratio (ACR, mg/g), and C-reactive protein (CRP) levels, skeletal muscle index (SMI), and quality of life (QOL) related to diabetes treatment were also determined. Seventeen patients (8; liraglutide group, 9; control group, mean age 59 ± 13 years; 53% female) completed this study. Liraglutide treatment significantly reduced VFA at 24 weeks; whereas, SFA was unchanged. ACR, LAI, and CRP levels were significantly reduced by liraglutide at 24 weeks and there was no difference in SMI between the two groups. Changes in VFA from baseline to 24 weeks were significantly associated with those in LAI, albuminuria, and HbA1c. Liraglutide treatment significantly improved QOL scores associated with anxiety and dissatisfaction with treatment and satisfaction with treatment. No severe adverse events were observed in both groups. Our data suggest that liraglutide could reduce visceral adiposity in parallel with attenuation of hepatic fat accumulation, albuminuria and micro-inflammation and improve QOL related to diabetes care in insulin-treated patients with type 2 diabetes.

Transcriptional regulation of the human Liver X Receptor α gene by Hepatocyte Nuclear Factor 4α.

Liver X Receptors (LXRs) are sterol-activated transcription factors that play major roles in cellular cholesterol homeostasis, HDL biogenesis and reverse cholesterol transport. The aim of the present study was to investigate the mechanisms that control the expression of the human LXRα gene in hepatic cells. A series of reporter plasmids containing consecutive 5' deletions of the hLXRα promoter upstream of the luciferase gene were constructed and the activity of each construct was measured in HepG2 cells. This analysis showed that the activity of the human LXRα promoter was significantly reduced by deleting the -111 to -42 region suggesting the presence of positive regulatory elements in this short proximal fragment. Bioinformatics data including motif search and ChIP-Seq revealed the presence of a potential binding motif for Hepatocyte Nuclear Factor 4 α (HNF-4α) in this area. Overexpression of HNF-4α in HEK 293T cells increased the expression of all LXRα promoter constructs except -42/+384. In line, silencing the expression of endogenous HNF-4α in HepG2 cells was associated with reduced LXRα protein levels and reduced activity of the -111/+384 LXRα promoter but not of the -42/+384 promoter. Using ChiP assays in HepG2 cells combined with DNAP assays we mapped the novel HNF-4α specific binding motif (H4-SBM) in the -50 to -40 region of the human LXRα promoter. A triple mutation in this H4-SBM abolished HNF-4α binding and reduced the activity of the promoter to 65% relative to the wild type. Furthermore, the mutant promoter could not be transactivated by HNF-4α. In conclusion, our data indicate that HNF-4α may have a wider role in cell and plasma cholesterol homeostasis by controlling the expression of LXRα in hepatic cells.

Expression of inflammation-related genes in aldosterone-producing adenomas with KCNJ5 mutation.

BACKGROUND: The adrenocortical cells have been shown to produce various inflammatory cytokines such as TNFα and IL-6, which could modulate steroidogenesis. However, the role of inflammatory cytokines in aldosterone-producing adenomas (APAs) is not fully understood. In the present study, we examined the relationships between mRNA expression levels of the inflammation-related genes and somatic mutations in APA tissues. METHODS: We evaluated mRNA expression levels of TNFA, IL6, and NFKB1 in APA tissues obtained from 44 Japanese APA patients. RESULTS: We revealed that mRNA expression patterns of the inflammation-related genes depended on a KCNJ5 somatic mutation. In addition, we showed that mRNA expression levels of the inflammation-related genes correlated with those of the steroidogenic enzyme CYP11B1 in the patients with APAs. CONCLUSION: The present study documented for the first time the expression of inflammation-related genes in APAs and the correlation of their expression levels with the KCNJ5 mutation status and mRNA expression levels of steroidogenic enzymes, indicating the pathophysiological relevance of inflammation-related genes in APAs.

Is visceral adiposity a modifier for the impact of blood pressure on arterial stiffness and albuminuria in patients with type 2 diabetes?

BACKGROUND: We aimed to investigate whether visceral adiposity could modify the impact of blood pressure on arterial stiffness and albuminuria in patients with type 2 diabetes. METHODS: This cross-sectional study examines the interaction of visceral adiposity with increased blood pressure on arterial stiffness and albuminuria. 638 patients with type 2 diabetes (mean age 64 ± 12 years; 40 % female) were enrolled. Visceral fat area (VFA, cm(2)) was assessed by a dual-impedance analyzer, whereby patients were divided into those with VFA < 100 (N = 341) and those with VFA ≥ 100 (N = 297). Albuminuria was measured in a single 24-h urine collection (UAE, mg/day) and brachial-ankle pulse wave velocity (ba-PWV, cm/s) was used for the assessment of arterial stiffening. Linear regression analyses were used to investigate the association of systolic blood pressure (SBP) and VFA with UAE and baPWV. RESULTS: Patients with VFA ≥ 100 were significantly younger, had higher SBP, HbA1c, triglycerides, UAE, alanine aminotransferase, C-reactive protein and lower high-density lipoprotein and shorter duration of diabetes than those with VFA < 100. SBP was significantly and almost equivalently associated with ba-PWV both in VFA < 100 (standardized ß 0.224, p = 0.001) and VFA ≥ 100 (standardized ß 0.196, p = 0.004) patients in the multivariate regression analysis adjusting for covariates including age, gender, HbA1c, diabetic complications and the use of insulin and anti-hypertensive agents. By contrast, the association of SBP with UAE was stronger in patients with VFA ≥ 100 (standardized ß 0.263, p = 0.001) than that in patients with VFA < 100 (standardized ß 0.140, p = 0.080) in the multivariate regression model. In the whole cohort, the significant interaction between SBP and VFA on UAE (standardized ß 0.172, p = 0.040) but not on ba-PWV (standardized ß -0.008, p = 0.916) was observed. CONCLUSIONS: The effect of increased blood pressure on arterial stiffness is almost similar in type 2 diabetic patients with both low and high visceral adiposity, while its association with albuminuria is stronger in the latter.