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Dysregulation of fatty acid utilization is increasingly recognized as a significant component of diabetic kidney disease. Rho-associated, coiled-coil-containing protein kinase (ROCK) is activated in the diabetic kidney, and studies over the past decade have illuminated ROCK signaling as an essential pathway in diabetic kidney disease. Here, we confirmed the distinct role of ROCK1, an isoform of ROCK, in fatty acid metabolism using glomerular mesangial cells and ROCK1 knockout mice. Mesangial cells with ROCK1 deletion were protected from mitochondrial dysfunction and redox imbalance driven by transforming growth factor β, a cytokine upregulated in diabetic glomeruli. We found that high-fat diet-induced obese ROCK1 knockout mice exhibited reduced albuminuria and histological abnormalities along with the recovery of impaired fatty acid utilization and mitochondrial fragmentation. Mechanistically, we found that ROCK1 regulates the induction of critical mediators in fatty acid metabolism, including peroxisome proliferator-activated receptor gamma coactivator 1α, carnitine palmitoyltransferase 1, and widespread program-associated cellular metabolism. Thus, our findings highlight ROCK1 as an important regulator of energy homeostasis in mesangial cells in the overall pathogenesis of diabetic kidney disease.

Background: Decreased physical function is divided into two categories: dynapenia with retained muscle mass and sarcopenia with loss of muscle mass. The differences in the characteristics of dynapenia and sarcopenia remain unclear. This study was performed to clarify the characteristics and risk factors of dynapenia and sarcopenia in elderly patients. Methods: This study involved 267 patients aged ≥ 65 years (111 men, 156 women). All patients underwent measurement of the (a) skeletal muscle index by bioelectrical impedance, (b) grip strength (index of muscle strength), and (c) walking speed (index of physical ability). Based on the Asian Working Group for Sarcopenia criteria, the patients were categorized into three groups: the control (C) group (n = 77), who had normal (b) and (c) regardless of (a); the dynapenia (D) group (n = 61), who had normal (a) with decreased (b) and/or (c); and the sarcopenia (S) group (n = 129), who had decreased (a) with decreased (b) and/or (c). The characteristics and risk factors in the C, D, and S groups were statistically analyzed. Results: The logistic analysis adjusted for age, sex, and body mass index (BMI) showed that the complication of diabetes, a stroke history, and a fracture history were significant risk factors in both the D and S groups compared with the C group. An osteoporosis-equivalent BMD of the femoral neck or lumbar spine (i.e., BMD of

The Aging Males' Symptoms (AMS) score, developed to screen for late-onset hypogonadism (LOH), contains 17 questions regarding mental, physical, and sexual parameters. In the Japanese guidelines, a free testosterone (FT)8.5 pg/mL is recommended for testosterone treatment. However, previous studies have shown no correlation between total AMS scores and testosterone concentration. We aimed to develop a better questionnaire for the detection of testosterone deficiency in men, for the diagnosis of LOH. In 234 Japanese men, aged 40-64 years, we analyzed the relationships of AMS with serum total testosterone (TT), FT, calculated FT (cFT), and calculated bioavailable testosterone (cBT), and identified useful questions for the detection of testosterone deficiency. Four scores, a decrease in muscular strength, a decrease in ability to perform sexually or the frequency, a decrease in the number of morning erections, and a decrease in sexual desire/libido, were negatively associated with two or more of the above four testosterone parameters, and the sum of these four scores (named the selective score) correlated with TT and cFT, independent of age. Statistical analysis revealed an association between insulin resistance and testosterone deficiency, and a higher selective score in smokers than non-smokers. Cubic function model analysis and logistic regression analysis revealed that selective scores ≥10 corresponded with the testosterone concentrations recommended for the diagnosis of LOH, including FT8.5 pg/mL, independent of age, insulin resistance, and smoking. Thus, the selective score represents a simple and useful means for screening of testosterone deficiency in Japanese men, as an indicator of LOH.

Cancer is a major cause of death in patients with diabetes. Incretin therapy has received much attention because of its tissue-protective effects. We have previously reported an anti-breast cancer effect of glucagon-like peptide-1 receptor agonist exendin-4 (Ex-4). An anti-cancer effect of metformin is well recognized. Therefore, we examined the effect of combined treatment with Ex-4 and metformin in breast cancer cells. In human breast cancer cell lines MCF-7, MDA-MB-231, and KPL-1, 0.1-10 mM metformin significantly reduced the cell number in growth curve analysis in a dose-dependent manner. Furthermore, combined treatment with 0.1 mM metformin and 10 nM Ex-4 additively attenuated the growth curve progression of breast cancer cells. In a bromodeoxyuridine (BrdU) assay, Ex-4 or metformin significantly decreased breast cancer cell proliferation and further reduction of BrdU incorporation was observed by combined treatment with Ex-4 and metformin, which suggested that Ex-4 and metformin additively decreased DNA synthesis in breast cancer cells. Although apoptotic cells were not observed among Ex-4-treated breast cancer cells, apoptotic cells were clearly detected among metformin-treated breast cancer cells by apoptosis assays. Furthermore, metformin decreased BCL-2 expression in MCF-7 cells. In vivo experiments using a xenograft model showed that Ex-4 and metformin significantly decreased the breast tumor weight and Ki67-positive proliferative cancer cells, and metformin reduced the serum insulin level in mice. These data suggested that Ex-4 and metformin attenuated cell proliferation and metformin induced apoptosis in breast cancer cells. Combined treatment of Ex-4 and metformin may be an optional therapy to inhibit breast cancer progression.

Purpose of review X-linked hypophosphatemia and tumor-induced osteomalacia are diseases characterized by hypophosphatemia with impaired proximal tubular phosphate reabsorption. Complete resection of responsible tumors is the first line therapy for patients with tumor-induced osteomalacia. In contrast, phosphate and active vitamin D have been used for patients with X-linked hypophosphatemia and inoperable ones with tumor-induced osteomalacia. The purpose of this review is to summarize the pathogenesis of these diseases and discuss about the new treatment. Recent findings Excessive FGF23 production has been shown to underline several kinds of hypophosphatemic rickets/osteomalacia including X-linked hypophosphatemia and tumor-induced osteomalacia. Burosumab, an anti-FGF23 monoclonal antibody, was approved for clinical use while the indications of burosumab are different depending on countries. Summary The inhibition of excessive FGF23 activity has been approved as a new therapy for several kinds of hypophosphatemic diseases. Further studies are necessary to clarify the long-term effects and safety of burosumab.

Introduction Both body mass index (BMI) and waist circumference (WC) are associated with diabetes risk, and the difference between them in predictive ability for diabetes is still contentious. We conducted a population-based study to investigate and compare the association of them with diabetes by sex. Methods This study included a total of 4754 subjects aged 40–80 years with no diabetes at baseline between 2008 and 2017. Using multivariate Cox proportional hazards models, we calculated hazard ratios for diabetes according to tertiles of BMI or WC. Harrell's C statistics was applied to assess and compare the predictive ability of the models using BMI and WC. Results Both BMI and WC showed the significant positive trends with diabetes risk. In men, the extreme tertiles (BMI > 25.1 kg/m2 and WC > 88.0 cm) provided 1.58-fold or 2.04-fold higher risk compared with the first tertiles ( 24.4 kg/m2 showed 3.28-fold higher risk than the first tertile (

Rho-associated, coiled-coil-containing protein kinase (ROCK) is activated in the diabetic kidney. Studies over the past decade have illuminated ROCK signaling as an essential pathway in the pathogenesis of diabetic nephropathy. Accumulating evidence shows that renal dysfunction among patient with diabetes is associated with abnormal fatty acid oxidation in the kidney. However, the interaction of ROCK and fatty acid oxidation in diabetic kidneys remains unclear. Extracellular flux analyzer demonstrated that deficiency of ROCK1, one of the ROCK isoforms, improves TGF-β-induced mitochondrial dysfunction in primary cultured mesangial cells. ROCK1 deficiency rescued TGF-β-induced downregulation of fatty acid oxidation mediators such as peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α) , and carnitine palmitoyltransferase 1A (CPT1A) . An investigation of mechanisms underlying this observation revealed activated ROCK1 axis through the phosphorylation of AMPK and increased expression of PGC-1α. Fluorescence histochemistry showed that ROCK1 deficiency suppresses ROS production induced by mitochondrial damage due to abnormal fatty acid metabolism. Consistent with this result, compared to wild-type mice, ROCK1 knockout mice exhibited reduced albuminuria and histological abnormalities along with the recovery of impaired fatty acid utilization and mitochondrial fragmentation. Furthermore, RNA-seq showed that ROCK1 deficiency in mesangial cells significantly altered the expression of genes involved in metabolic pathway. These observations indicate that ROCK1 is a key player in the development of diabetic renal injury. ROCK1 may be a potential therapeutic target for the treatment of diabetic nephropathy. Disclosure Y.Nagai: None. K.Matoba: None. K.Sekiguchi: None. Y.Takeda: None. Y.Kanazawa: None. D.Kawanami: None. K.Utsunomiya: None. R.Nishimura: Speaker's Bureau; Abbott Diabetes, Astellas Pharma Inc., AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic, Merck & Co., Inc., Novo Nordisk, Ono Pharmaceutical Co., Ltd., Sanofi, Taisho Pharmaceutical Holdings Co., Ltd., Takeda Pharmaceutical Company Limited, Teijin Pharma Limited, Terumo Corporation.

Moritsugu Kimura,1 Masao Toyoda,1 Nobumichi Saito,1 Makiko Takahashi,1 Konomi Isozumi,1 Eri Kato,2 Daiji Kawanami,3 Masafumi Fukagawa1 1Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan; 2Seichi Clinic, Isehara, Kanagawa, Japan; 3Department of Endocrinology and Diabetes Mellitus, Fukuoka University School of Medicine, Fukuoka, JapanCorrespondence: Moritsugu Kimura, Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan, Tel +81-463-93-1121 (ext. 2490), Fax +81-463-91-3350, Email moritsug@is.icc.u-tokai.ac.jpAbstract: Despite some negative reports regarding the need for the self-monitoring of blood glucose (SMBG), including the issue of cost-effectiveness, there are still many users, and in diabetes treatment, which is largely dependent on the patient’s self-care, SMBG remains an important tool in establishing such self-care habits, with several reports supporting this notion. In addition, devices are needed to assist in SMBG for patients with diabetes who have difficulty performing SMBG, such as the elderly or those with visual impairment. In current diabetes care, it is reported that patient-centered care that respects the preferences, needs, and values of individual patients and personalized care that consider the characteristics and comorbidities of each patient are important. Through a case study of a patient with diabetes who had difficulty performing SMBG due to visual impairment, we learned of the needs of SMBG and its assistive devices and the importance of patient and family engagement with emphasis on patient-centered and personalized care. We herein report what we learned through this case in the form of perspectives. Through this report, we hope that medical professionals involved in diabetes care will learn of the importance and needs of these issues and apply them to their actual clinical practice.Graphical Abstract: Keywords: patient-centered care, personalized care, patient and family engagement, self-monitoring of blood glucose, SMBG assistive devices, diabetes

Aim To evaluate the effect of canagliflozin, a sodium-glucose co-transporter-2 (SGLT2) inhibitor, on albuminuria and the decline of estimated glomerular filtration rate (eGFR) in participants with type 2 diabetes and microalbuminuria. Methods The CANPIONE study is a multicentre, randomized, parallel-group and open-labelled study consisting of a unique 24-week preintervention period, during which the rate of eGFR decline before intervention is estimated, followed by a 52-week intervention and a 4-week washout period. Participants with a geometric mean urinary albumin-to-creatinine ratio (UACR) of 50 and higher and less than 300 mg/g in two consecutive first-morning voids at two different time points, and an eGFR of 45 ml/min/1.73m2 or higher, are randomly assigned to receive canagliflozin 100 mg daily or to continue guideline-recommended treatment, except for SGLT2 inhibitors. The first primary outcome is the change in UACR, and the second primary outcome is the change in eGFR slope. Results A total of 258 participants were screened and 98 were randomized at 21 sites in Japan from August 2018 to May 2021. The mean baseline age was 61.4 years and 25.8% were female. The mean HbA1c was 7.9%, mean eGFR was 74.1 ml/min/1.73m2 and median UACR was 104.2 mg/g. Conclusions The CANPIONE study will determine whether the SGLT2 inhibitor canagliflozin can reduce albuminuria and slow eGFR decline in participants with type 2 diabetes and microalbuminuria.

Aims/Introduction Incretin therapy is a common treatment for type 2 diabetes mellitus. We have previously reported an anti‐prostate cancer effect of glucagon‐like peptide‐1 receptor (GLP‐1R) agonist exendin‐4. The attenuation of cell proliferation in the prostate cancer cell line was dependent on GLP‐1R expression. Here, we examined the relationship between human prostate cancer severity and GLP‐1R expression, as well as the effect of forced expression of GLP‐1R using a lentiviral vector. Materials and Methods Prostate cancer tissues were extracted by prostatectomy and biopsy. GLP‐1R was overexpressed in ALVA‐41 cells using a lentiviral vector (ALVA‐41‐GLP‐1R cells). GLP‐1R expression was detected by immunohistochemistry and quantitative polymerase chain reaction. Cell proliferation was examined by growth curves and bromodeoxyuridine incorporation assays. Cell cycle distribution and regulators were examined by flow cytometry and western blotting. In vivo experiments were carried out using a xenografted model. Results GLP‐1R expression levels were significantly inversely associated with the Gleason score of human prostate cancer tissues. Abundant GLP‐1R expression and functions were confirmed in ALVA‐41‐GLP‐1R cells. Exendin‐4 significantly decreased ALVA‐41‐GLP‐1R cell proliferation in a dose‐dependent manner. DNA synthesis and G1‐to‐S phase transition were inhibited in ALVA‐41‐GLP‐1R cells. SKP2 expression was decreased and p27Kip1 protein was subsequently increased in ALVA‐41‐GLP‐1R cells treated with exendin‐4. In vivo experiments carried out by implanting ALVA‐41‐GLP‐1R cells showed that exendin‐4 decreased prostate cancer growth by activation of GLP‐1R overexpressed in ALVA41‐GLP‐1R cells. Conclusions Forced expression of GLP‐1R attenuates prostate cancer cell proliferation by inhibiting cell cycle progression in vitro and in vivo. Therefore, GLP‐1R activation might be a potential therapy for prostate cancer., Forced expression of glucagon‐like peptide‐1 receptor attenuates prostate cancer cell proliferation by inhibiting cell cycle progression both in vitro and in vivo. Glucagon‐like peptide‐1 receptor activation might be a potential therapy for not only type 2 diabetes, but also prostate cancer.

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease and is strongly associated with cardiovascular mortality. Given the pandemic of obesity and diabetes, the elucidation of the molecular underpinnings of DKD and establishment of effective therapy are urgently required. Studies over the past decade have identified the activated renin-angiotensin system (RAS) and hemodynamic changes as important therapeutic targets. However, given the residual risk observed in patients treated with RAS inhibitors and/or sodium glucose co-transporter 2 inhibitors, the involvement of other molecular machinery is likely, and the elucidation of such pathways represents fertile ground for the development of novel strategies. Rho-kinase (ROCK) is a serine/threonine kinase that is under the control of small GTPase protein Rho. Many fundamental cellular processes, including migration, proliferation, and survival are orchestrated by ROCK through a mechanism involving cytoskeletal reorganization. From a pathological standpoint, several analyses provide compelling evidence supporting the hypothesis that ROCK is an important regulator of DKD that is highly pertinent to cardiovascular disease. In cell-based studies, ROCK is activated in response to a diverse array of external stimuli associated with diabetes, and renal ROCK activity is elevated in the context of type 1 and 2 diabetes. Experimental studies have demonstrated the efficacy of pharmacological or genetic inhibition of ROCK in the prevention of diabetes-related histological and functional abnormalities in the kidney. Through a bird's eye view of ROCK in renal biology, the present review provides a conceptual framework that may be widely applicable to the pathological processes of multiple organs and illustrate novel therapeutic promise in diabetology.

Bone contributes to supporting the body, protecting the central nervous system and other organs, hematopoiesis, the regulation of mineral metabolism (mainly calcium and phosphate), and assists in respiration. Bone has many functions in the body. Recently, it was revealed that bone also works as an endocrine organ and secretes several systemic humoral factors, including fibroblast growth factor 23 (FGF23), osteocalcin (OC), sclerostin, and lipocalin 2. Bone can communicate with other organs via these hormones. In particular, it has been reported that these bone-derived hormones are involved in glucose metabolism and diabetic complications. Some functions of these bone-derived hormones can become useful biomarkers that predict the incidence of diabetes and the progression of diabetic complications. Furthermore, other functions are considered to be targets for the prevention or treatment of diabetes and its complications. As is well known, diabetes is now a worldwide health problem, and many efforts have been made to treat diabetes. Thus, further investigations of the endocrine system through bone-derived hormones may provide us with new perspectives on the prediction, prevention, and treatment of diabetes. In this review, we summarize the role of bone-derived hormones in glucose metabolism, diabetic kidney disease, and cardiovascular disorders.

Diabetic kidney disease (DKD) is a major cause of end-stage kidney disease (ESKD) worldwide. Mineralocorticoid receptor (MR) plays an important role in the development of DKD. A series of preclinical studies revealed that MR is overactivated under diabetic conditions, resulting in promoting inflammatory and fibrotic process in the kidney. Clinical studies demonstrated the usefulness of MR antagonists (MRAs), such as spironolactone and eplerenone, on DKD. However, concerns regarding their selectivity for MR and hyperkalemia have remained for these steroidal MRAs. Recently, nonsteroidal MRAs, including finerenone, have been developed. These agents are highly selective and have potent anti-inflammatory and anti-fibrotic properties with a low risk of hyperkalemia. We herein review the current knowledge and future perspectives of MRAs in DKD treatment.

We aimed to investigate the association between serum uric acid (SUA) level and development of hypertension as well as the interaction effect of chronic kidney disease (CKD) on this relationship in the general Japanese population. We included 7895 participants aged ≥30 years from the ISSA-CKD study, a population-based retrospective cohort study that used annual health check-up data of residents from Iki Island, Japan. After the exclusion of 1881 with l < 1-year follow-up, 2812 with hypertension at baseline, and 165 with missing information on SUA, a total of 3037 participants were enrolled in this analysis. Participants were divided into four groups according to the quartiles of SUA level at baseline, and multivariable-adjusted hazard ratios for new-onset hypertension were calculated. Stratified analyses were performed for each subgroup (defined by sex, age, alcohol intake, and CKD) to assess the interaction effects. During a mean follow-up period of 4.4 years, 943 participants developed hypertension. The first quartile group was set as the reference group, and the multivariable-adjusted hazard ratios (95% confidence interval) for new-onset hypertension were 1.11 (0.90-1.36) in the second quartile, 1.25 (1.02-1.54) in the third quartile, and 1.35 (1.07-1.70) in the fourth quartile compared with those in the reference group (p = .007 for trend). The stratified analyses showed that the association between SUA and hypertension was significantly stronger in participants with CKD than in those without CKD (p = .035 for interaction). SUA level is an independent risk factor for new-onset hypertension. This tendency was significantly stronger in participants with CKD.

Background: We investigated whether eating speed was associated with the incidence of diabetes in a Japanese general population. Methods: A total of 4853 Japanese individuals without diabetes at baseline were analyzed. Self-reported eating speed was categorized as slow, medium, and fast on the basis of questionnaire responses. The study outcome was the incidence of diabetes. Results: After an average follow-up period of 5.1 years, 234 individuals developed diabetes. The incidence of diabetes per 1000 person-years was 4.9 in the slow eating speed group, 8.8 in the medium eating speed group, and 12.5 in the fast eating speed group, respectively (*** p &lt, 0.001 for trend). The HRs were 1.69 (95%CI 0.94–3.06) for the medium eating speed and 2.08 (95%CI 1.13–3.84) for the fast eating speed, compared to the slow eating speed (* p = 0.014 for trend) after adjustment for age, gender, smoking status, drinking, exercise, obesity, hypertension, and dyslipidemia. Conclusion: Faster eating speed increased a risk for the incidence of diabetes in a general Japanese population.

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD) worldwide. Dipeptidyl peptidase (DPP)-4 inhibitors are widely used in the treatment of patients with type 2 diabetes (T2D). DPP-4 inhibitors reduce glucose levels by inhibiting degradation of incretins. DPP-4 is a ubiquitous protein with exopeptidase activity that exists in cell membrane-bound and soluble forms. It has been shown that an increased renal DPP-4 activity is associated with the development of DKD. A series of clinical and experimental studies showed that DPP-4 inhibitors have beneficial effects on DKD, independent of their glucose-lowering abilities, which are mediated by anti-fibrotic, anti-inflammatory, and anti-oxidative stress properties. In this review article, we highlight the current understanding of the clinical efficacy and the mechanisms underlying renoprotection by DPP-4 inhibitors under diabetic conditions.

SARS-CoV-2 infection is associated with thyroid disorders. It has been reported that myxedema coma (MC) can be complicated with COVID-19. COVID-19-related thyroid disorders consist of a broad spectrum of thyroid dysfunction, from thyrotoxicosis to decompensated hypothyroidism. It is possible that both primary and central thyroid disorders are induced by COVID-19 due to systemic inflammatory and immune responses. We experienced two cases in which patients with COVID-19 developed MC with central hypothyroidism. It is likely that MC affected the severity of COVID-19. It is necessary to consider the existence of MC during SARS-CoV-2 infection. We propose the potential mechanisms.

The aim of this study was to determine the relationship between eating before bed and the development of hypertension in a general Japanese population. We conducted a population-based retrospective cohort study using annual health check-up data collected from the residents of Iki City, Nagasaki Prefecture, Japan. In total, 2930 participants without hypertension at baseline (mean age 57.0 years, male 42.8%) were included in the present analysis. Eating before bed was defined as eating within 2 h of bedtime. The outcome of this study was incident hypertension (blood pressure ≥140/90 mmHg or initiation of blood pressure-lowering medications). Multivariable-adjusted hazard ratios and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. During an average follow-up of 4.5 years, 909 participants developed hypertension. The incidence (per 1000 person-years) of hypertension in the group of individuals who ate before bed was 82.8, whereas that in the group of individuals who did not eat before bed was 65.8. The association was significant even after adjusting for other risk factors, including age, sex, current smoking status, current alcohol intake, regular exercise, obesity, elevated blood pressure, diabetes mellitus, and dyslipidemia, with a hazard ratio of 1.23 (95% CI: 1.05-1.44) for the group of individuals who ate before bed compared with the group of individuals who did not eat before bed (P = 0.01 for trend). Eating before bed was correlated with a future risk of developing hypertension in the general Japanese population.

Cancer is a major cause of death in patients with type 2 diabetes mellitus (T2DM) and lung cancer is one of the most prevalent cancers in patients with T2DM. In the present study, we examined the anti-cancer effect of the Sodium-glucose cotransporter 2 (SGLT2) inhibitor, canagliflozin, using a lung cancer model. In lung cancer tissues from non-T2DM human subjects, SGLT2 was detected by immunohistochemistry. SGLT2 mRNA and protein were also detected in A549, H1975 and H520 lung cancer cell lines by RT-PCR and immunohistochemistry, respectively. Canagliflozin at 1–50 µM significantly suppressed the growth of A549 cells in a dose-dependent manner. In BrdU assays, canagliflozin attenuated the proliferation of A549 cells, but did not induce apoptosis. In cell cycle analysis, S phase entry was attenuated by canagliflozin in A549 cells. In in vivo experiments, a xenograft model of athymic mice implanted with A549 lung cancer cells was treated with low and high dose oral canagliflozin. Despite the results of the in vitro experiments, tumor weight was not decreased by canagliflozin. In addition, the serum insulin level, but not body weight or blood glucose level, was decreased by canagliflozin. The number of cells positive for Ki67 was slightly decreased by canagliflozin, but this was not statistically significant. In conclusion, SGLT2 is expressed in human lung cancer tissue and cell lines, and the SGLT2 inhibitor, canagliflozin, attenuated proliferation of A549 lung cancer cells by inhibiting cell cycle progression in vitro but not in vivo.

Cinacalcet is a calcimimetic that modulates the functions of calcium-sensing receptor and is currently used to treat patients with primary hyperparathyroidism (PHPT). Although it was reported that cinacalcet treatment reduced the size of hyperplastic parathyroid glands in patients with secondary hyperparathyroidism, whether or not cinacalcet treatment can reduce the size of parathyroid adenomas in patients with PHPT has been unknown. We recruited nine (male: one, female: eight) patients with PHPT due to parathyroid adenomas who did not undergo parathyroidectomy. Cinacalcet was administered at a dose of 50 mg/day, and we evaluated the size of parathyroid adenomas (width × thickness) (mm2) using ultrasonography before and after 6 months of cinacalcet treatment. The mean age of the subjects was 58.1 ± 7.2 years old, and the mean serum intact parathyroid hormone (PTH) concentration was 134.8 ± 8.7 pg/ml. All participants showed hypercalcemia and osteopenia. After 6 months, the mean size of parathyroid adenomas was significantly decreased (baseline: 73.8 ± 33.4 mm2 vs. after 6 months: 52.5 ± 25.0 mm2, p = 0.045). Thus, 6-month cinacalcet treatment induced a 29% size reduction in parathyroid adenomas. Furthermore, the serum intact PTH concentration before cinacalcet treatment was positively correlated with the reduction in the size of parathyroid adenomas. The present study revealed that cinacalcet treatment reduces the size of parathyroid adenomas in patients with PHPT. The accumulation of more PHPT cases with cinacalcet therapy is required to confirm this finding.

Intraperitoneal fat is considered a particularly important risk factor for impaired glucose tolerance, dyslipidemia, and coronary heart diseases. However, the underlying mechanisms in obesity are not fully understood. The small GTPase Rho and its downstream effector, Rho-kinase (ROCK), regulate various cellular functions, including organization of the actin cytoskeleton, cell adhesion and expression of genes. Recent studies have shown that Rho/ROCK signaling is strongly related to diabetic vascular complications. ROCK has two isoforms, ROCK1 and ROCK2. Systemic gene deletion studies in mice suggest that these isoforms have distinctive roles in regulating cellular function. In this study, we investigated specific roles of endothelial ROCK2 in the progression of obesity. We mated ROCK2 floxed mice with VE-cadherin-cre mice to generate endothelial-ROCK2 knockout mice (ER2KO). ER2KO mice are resistant to weight gain and glucose intolerance induced by high fat diet. White adipose tissue (WAT) weight was lower in ER2KO mice compared with wild type mice. Histological analysis revealed that adipose droplets were smaller in ER2KO than wild type mice. Browning, the conversion of WAT to a beige phenotype, activates thermogenic function, suppresses obesity and improves glucose and lipid metabolism. Interestingly, we observed an increase of mRNA expression of browning marker including PPARα, CIDEA, PRDM16, UCP1, and specific markers of M2 macrophages in WAT of ER2KO mice regardless of whether they had been fed a normal chow or high fat diet. Collectively, the present study suggests that endothelial ROCK2 regulates glucose and lipid metabolism by suppressing browning of WAT. ROCK2 could be an important therapeutic target against obesity. Disclosure Y. Takeda: None. K. Matoba: Research Support; Self; Sanofi K.K., Takeda Pharmaceutical Company Limited. D. Kawanami: None. Y. Nagai: None. Y. Kanazawa: None. R. Nishimura: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc. Speaker’s Bureau; Self; Abbott, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly Japan K.K., Medtronic, Merck & Co., Inc., Novo Nordisk Inc., Sanofi K.K., Takeda Pharmaceutical Company Limited.

The small GTPase Rho and its effector, Rho-kinase (ROCK), are implicated in the fundamental cellular processes (e.g., cell adhesion, migration). Studies over the past decade have illuminated ROCK as an important regulator of diabetic kidney disease. We previously demonstrated elevated renal ROCK activity in both type 1 and type 2 diabetic murine models. In an attempt to elucidate the roles of the activated ROCK, we provided evidence that ROCK inhibition attenuates an increase of urinary albumin excretion, glomerular sclerosis, and podocyte loss in rodents. Mechanistically, ROCK regulates inflammatory events as well as hypoxia-induced fibrotic reactions. However, specific roles of ROCK isoforms, ROCK1 and ROCK2, in diabetic kidneys remain unclear. In the present study, we first investigated the renal distribution of ROCK1 and ROCK2 using wild type mice and human kidneys obtained at necropsy. The immunohistochemical analysis detected both isoforms in glomeruli, tubules, and vessel walls. Whereas ROCK1 was mainly expressed in the cytoplasm, ROCK2 was accumulated in the nucleus of these cells. Double staining with anti-nephrin antibody showed co-localization of ROCK2 with nephrin, indicating distinctive roles of ROCK2 in the glomerular podocyte. In order to elucidate the role of podocyte ROCK2, we next evaluated gene expression levels of ROCK2 in high-fat diet-fed mice and patients with diabetic kidney disease. In both mice and patients, ROCK2 was increased in the setting of diabetes compared to healthy subjects. Of note, glomerular ROCK2 mRNA levels were positively correlated with the increase of urinary albumin excretion in mice. When considered alongside our previous observations, the current work highlights the importance of ROCK2 in diabetic podocytopathy. Disclosure K. Matoba: Research Support; Self; Sanofi K.K., Takeda Pharmaceutical Company Limited. Y. Takeda: None. Y. Nagai: None. T. Akamine: None. Y. Kanazawa: None. D. Kawanami: None. K. Utsunomiya: None. R. Nishimura: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc. Speaker’s Bureau; Self; Abbott, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly Japan K.K., Medtronic, Merck & Co., Inc., Novo Nordisk Inc., Sanofi K.K., Takeda Pharmaceutical Company Limited. Funding Japan Society for the Promotion of Science (18K15985)

The small GTPase Rho and its effector Rho-kinase are involved in the pathogenesis of diabetic kidney disease. Accumulating evidence shows that renal dysfunction in diabetic patient is associated with abnormal fatty acid oxidation in the kidney. However, the interaction of Rho-kinase and fatty acid oxidation in diabetic kidney remain unclear. Glomeruli isolated from type 2 diabetic db/db mice demonstrated decreased gene expression of fatty acid oxidation mediators such as peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), CD36, carnitine palmitoyltransferase 1A (CPT1A). Chemical inhibition of Rho-kinase restored expression of fatty acid oxidation-related genes in both isolated glomeruli and cultured mesangial cells. An investigation of mechanisms underlying this observation revealed activated Rho-kinase functions through the phosphorylation of AMPK and increased expression of PGC-1α. Extracellular flux analyzer demonstrated that Rho-kinase inhibition improves TGF-β-induced mitochondrial dysfunction. Furthermore, fluorescence histochemistry showed that Rho-kinase inhibitors suppresses ROS production as a result of mitochondrial damage due to abnormal fatty acid metabolism. Knockdown by small interfering RNA against two Rho-kinase isoforms, ROCK1 and ROCK2, showed that ROCK1 but not ROCK2 controls this metabolic machinery. Consistent with this result, mesangial cells isolated from ROCK1 deficient mice were protected from TGF-β-mediated downregulation of fatty acid metabolism. These observations indicate that ROCK1 is a key player in the development of diabetic renal injury. Glomerular ROCK1 may be a potential therapeutic target for the treatment of diabetic kidney disease. Disclosure Y. Nagai: None. K. Matoba: Research Support; Self; Sanofi K.K., Takeda Pharmaceutical Company Limited. Y. Takeda: None. T. Akamine: None. D. Kawanami: None. K. Utsunomiya: None. R. Nishimura: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc. Speaker’s Bureau; Self; Abbott, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly Japan K.K., Medtronic, Merck & Co., Inc., Novo Nordisk Inc., Sanofi K.K., Takeda Pharmaceutical Company Limited.

Metformin is a glucose-lowering agent that is used as a first-line therapy for type 2 diabetes (T2D). Based on its various pharmacologic actions, the renoprotective effects of metformin have been extensively studied. A series of experimental studies demonstrated that metformin attenuates diabetic kidney disease (DKD) by suppressing renal inflammation, oxidative stress and fibrosis. In clinical studies, metformin use has been shown to be associated with reduced rates of mortality, cardiovascular disease and progression to end-stage renal disease (ESRD) in T2D patients with chronic kidney disease (CKD). However, metformin should be administered with caution to patients with CKD because it may increase the risk of lactic acidosis. In this review article, we summarize our current understanding of the safety and efficacy of metformin for DKD.

Dipeptidyl peptidase-4 inhibitors (DPP-4Is) are one of the most frequently prescribed anti-diabetic agents in Japan, and they are often used in combination with insulin secretagogues, such as sulfonylureas and glinides. In the present study, we determined the efficacy and safety of the use of repaglinide or glimepiride, a sulfonylurea, in combination with a DPP-4I, in Japanese patients with type 2 diabetes mellitus (T2DM). This study was an investigator-initiated, open-label, randomized, multi-center prospective study. Patients with T2DM, which was inadequately controlled using a DPP-4I, were randomized to a repaglinide group or a glimepiride group and treated for 48 weeks. The primary outcomes were the reductions in glycated hemoglobin (HbA1c) and glucose oscillation, identified using continuous glucose monitoring, after 12 weeks. The secondary outcome was the change in carotid intima-media thickness (IMT), measured by ultrasonography, after 48 weeks. A total of 61 patients were recruited and analyzed in the study. Twelve weeks of treatment with 1.5 mg repaglinide or 1 mg glimepiride significantly reduced HbA1c, and a larger reduction in HbA1c occurred in the repaglinide group than the glimepiride group. Mean subcutaneous glucose concentration was significantly reduced in both groups, but the glucose oscillation did not decrease. Interestingly, the mean left IMT significantly increased in the glimepiride group, but not in the repaglinide group. More hypoglycemic events were observed in the glimepiride group. These data suggest that repaglinide reduces HbA1c more effectively than glimepiride when used in combination with a DPP-4I, and causes fewer hypoglycemic events. TRAIL REGISTRY: This study is registered with UMIN-CTR (UMIN000018321).

Co-culture models of neurons and Schwann cells have been utilized for the study of myelination and demyelination in the peripheral nervous system; in most of the previous studies, however, these cells were obtained by primary culture with embryonic or neonatal animals. A spontaneously immortalized Schwann cell line IFRS1 from long-term cultures of adult Fischer rat peripheral nerves has been shown to retain fundamental ability to myelinate neurites in co-cultures with adult rat dorsal root ganglion neurons and nerve growth factor-primed PC12 cells. Our current investigation focuses on the establishment of stable co-culture system with IFRS1 cells and NSC-34 motor neuron-like cells. NSC-34 cells were seeded at a low density (2 × 103/cm2) and maintained for 5–7 days in serum-containing medium supplemented with non-essential amino acids and brain-derived neurotrophic factor (BDNF; 10 ng/mL). Upon observation of neurite outgrowth under a phase-contrast microscope, the NSC-34 cells were exposed to an anti-mitotic agent mitomycin C (1 µg/mL) for 12–16 h, then co-cultured with IFRS1 cells (2 × 104/cm2), and maintained in serum-containing medium supplemented with ascorbic acid (50 µg/mL), BDNF (10 ng/mL), and ciliary neurotrophic factor (10 ng/mL). Double immunofluorescence staining carried out at day 28 of the co-culture showed myelin protein (P0 or PMP22)-immunoreactive IFRS1 cells surrounding the βIII tubulin-immunoreactive neurites. This co-culture system can be a beneficial tool to study the pathogenesis of motor neuron diseases (e.g., amyotrophic lateral sclerosis, Charcot–Marie–Tooth diseases, and immune-mediated demyelinating neuropathies) and novel therapeutic approaches against them.

Fibroblast growth factor (FGF) 23 produced by the bone is the principal hormone to regulate serum phosphate level. Serum FGF23 needs to be tightly regulated to maintain serum phosphate in a narrow range. Thus, we hypothesized that the bone has some phosphate-sensing mechanism to regulate the production of FGF23. Previously we showed that extracellular phosphate induces the phosphorylation of FGF receptor 1 (FGFR1) and FGFR1 signaling regulates the expression of Galnt3, whose product works to increase FGF23 production in vitro. In this study, we show the significance of FGFR1 in the regulated FGF23 production and serum phosphate level in vivo. We generated late-osteoblast/osteocyte-specific Fgfr1-knockout mice (Fgfr1fl/fl; OcnCre/+) by crossing the Ocn-Cre and the floxed Fgfr1 mouse lines. We evaluated serum phosphate and FGF23 levels, the expression of Galnt3 in the bone, the body weight and life span. A selective ablation of Fgfr1 aborted the increase of serum active full-length FGF23 and the enhanced expression of Galnt3 in the bone by a high phosphate diet. These mice showed more pronounced hyperphosphatemia compared with control mice. In addition, these mice fed with a control diet showed body weight loss after 23 weeks of age and shorter life span. These results reveal a novel significance of FGFR1 signaling in the phosphate metabolism and normal life span.

The aim of this study was to investigate the effects of long-term weight gain from the age of 20 on incidence of hyper-low-density-lipoprotein (LDL) cholesterolemia in the general population of Japanese people. Methods: We conducted a population-based retrospective cohort study using annual health checkup data for residents of Iki City, Nagasaki Prefecture, Japan. A total of 3179 adult (≥30 years old) men and women without hyper-LDL cholesterolemia at baseline, who underwent two or more health checkups were included in the analysis. Information on weight gain (≥10 kg) after 20 years of age was obtained using questionnaire. The outcome of this study was development of hyper-LDL cholesterolemia defined as LDL-cholesterol level ≥3.62 mmol/L and/or initiation of lipid-lowering medications. Results: During a mean follow-up period of 4.53 years, 665 of the 3179 participants developed hyper-LDL cholesterolemia (46.5/1000 person-years). The incidence of hyper-LDL cholesterolemia was higher in participants with a weight gain of ≥10 kg (55.3/1000 person-years) than among those with a weight gain of &lt, 10 kg (41.8/1000 person-years). This association remained statistically significant even after adjustment for age, sex, smoking, daily drinking, exercise, obesity, hypertension, and diabetes (multivariable hazard ratio 1.31, 95% confidence interval 1.08–1.58, p = 0.006). Conclusion: A weight gain of ≥10 after 20 years of age affected the development of hyper-LDL cholesterol regardless of age, sex, and obesity in a general population of Japanese.

Cancer is currently one of the major causes of death in patients with type 2 diabetes mellitus. We previously reported the beneficial effects of the glucagon-like peptide-1 receptor agonist exendin-4 against prostate and breast cancer. In the present study, we examined the anti-cancer effect of the sodium-glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin using a breast cancer model. In human breast cancer MCF-7 cells, SGLT2 expression was detected using both RT-PCR and immunohistochemistry. Ipragliflozin at 1-50 μM significantly and dose-dependently suppressed the growth of MCF-7 cells. BrdU assay also revealed that ipragliflozin attenuated the proliferation of MCF-7 cells in a dose-dependent manner. Because the effect of ipragliflozin against breast cancer cells was completely canceled by knocking down SGLT2, ipragliflozin could act via inhibiting SGLT2. We next measured membrane potential and whole-cell current using the patch clamp technique. When we treated MCF-7 cells with ipragliflozin or glucose-free medium, membrane hyperpolarization was observed. In addition, glucose-free medium and knockdown of SGLT2 by siRNA suppressed the glucose-induced whole-cell current of MCF-7 cells, suggesting that ipragliflozin inhibits sodium and glucose cotransport through SGLT2. Furthermore, JC-1 green fluorescence was significantly increased by ipragliflozin, suggesting the change of mitochondrial membrane potential. These findings suggest that the SGLT2 inhibitor ipragliflozin attenuates breast cancer cell proliferation via membrane hyperpolarization and mitochondrial membrane instability.