NFIA in adipocytes reciprocally regulates mitochondrial and inflammatory gene program to improve glucose homeostasis.

Adipose tissue is central to regulation of energy homeostasis. Adaptive thermogenesis, which relies on mitochondrial oxidative phosphorylation (Ox-Phos), dissipates energy to counteract obesity. On the other hand, chronic inflammation in adipose tissue is linked to type 2 diabetes and obesity. Here, we show that nuclear factor I-A (NFIA), a transcriptional regulator of brown and beige adipocytes, improves glucose homeostasis by upregulation of Ox-Phos and reciprocal downregulation of inflammation. Mice with transgenic expression of NFIA in adipocytes exhibited improved glucose tolerance and limited weight gain. NFIA up-regulates Ox-Phos and brown-fat-specific genes by enhancer activation that involves facilitated genomic binding of PPARγ. In contrast, NFIA in adipocytes, but not in macrophages, down-regulates proinflammatory cytokine genes to ameliorate adipose tissue inflammation. NFIA binds to regulatory region of the Ccl2 gene, which encodes proinflammatory cytokine MCP-1 (monocyte chemoattractant protein-1), to down-regulate its transcription. CCL2 expression was negatively correlated with NFIA expression in human adipose tissue. These results reveal the beneficial effect of NFIA on glucose and body weight homeostasis and also highlight previously unappreciated role of NFIA in suppressing adipose tissue inflammation.

Variation in plasma glucagon levels according to obesity status in Japanese Americans with normal glucose tolerance.

Japanese Americans living in the United States are genetically identical to Japanese people, but have undergone a rapid and intense westernization of their lifestyle. This study investigated variability in glucagon secretion after glucose loading among Japanese Americans with normal glucose tolerance (NGT) according to obesity status. The 75-g oral glucose tolerance test (OGTT) was performed for 138 Japanese Americans (aged 40-75 years) living in Los Angeles. Plasma glucagon levels measured using the sandwich enzyme-linked immunosorbent assay were compared according to body mass index (BMI) categories among 119 individuals with NGT. The individuals were classified into three categories according to their BMI values: <22 kg/m2 (n = 37), 22-24.9 kg/m2 (n = 46), and ≥25 kg/m2 (n = 36). Fasting plasma glucagon levels and glucagon-area under the curve levels during the OGTT were the highest in the BMI ≥25 kg/m2 group. Fasting glucagon levels were correlated with BMI (r = 0.399, p < 0.001), fasting insulin levels (r = 0.275, p = 0.003) and the homeostasis model assessment-insulin resistance (r = 0.262, p = 0.004). In conclusion, our findings suggest that fasting hyperglucagonemia is associated with obesity and insulin resistance even during the NGT stage in the Japanese American population.

ATP1A1 Mutant in Aldosterone-Producing Adenoma Leads to Cell Proliferation.

The molecular mechanisms by which ATP1A1 mutation-mediated cell proliferation or tumorigenesis in aldosterone-producing adenomas (APAs) have not been elucidated. First, we investigated whether the APA-associated ATP1A1 L104R mutation stimulated cell proliferation. Second, we aimed to clarify the molecular mechanisms by which the ATP1A1 mutation-mediated cell proliferated. We performed transcriptome analysis in APAs with ATP1A1 mutation. ATP1A1 L104R mutation were modulated in human adrenocortical carcinoma (HAC15) cells (ATP1A1-mutant cells), and we evaluated cell proliferation and molecular signaling events. Transcriptome and immunohistochemical analysis showed that Na/K-ATPase (NKA) expressions in ATP1A1 mutated APA were more abundant than those in non-functioning adrenocortical adenoma or KCNJ5 mutated APAs. The significant increase of number of cells, amount of DNA and S-phase population were shown in ATP1A1-mutant cells. Fluo-4 in ATP1A1-mutant cells were significantly increased. Low concentration of ouabain stimulated cell proliferation in ATP1A1-mutant cells. ATP1A1-mutant cells induced Src phosphorylation, and low concentration of ouabain supplementation showed further Src phosphorylation. We demonstrated that NKAs were highly expressed in ATP1A1 mutant APA, and the mutant stimulated cell proliferation and Src phosphorylation in ATP1A1-mutant cells. NKA stimulations would be a risk factor for the progression and development to an ATP1A1 mutant APA.

EHMT1 controls brown adipose cell fate and thermogenesis through the PRDM16 complex.

Brown adipose tissue (BAT) dissipates chemical energy in the form of heat as a defence against hypothermia and obesity. Current evidence indicates that brown adipocytes arise from Myf5(+) dermotomal precursors through the action of PR domain containing protein 16 (PRDM16) transcriptional complex. However, the enzymatic component of the molecular switch that determines lineage specification of brown adipocytes remains unknown. Here we show that euchromatic histone-lysine N-methyltransferase 1 (EHMT1) is an essential BAT-enriched lysine methyltransferase in the PRDM16 transcriptional complex and controls brown adipose cell fate. Loss of EHMT1 in brown adipocytes causes a severe loss of brown fat characteristics and induces muscle differentiation in vivo through demethylation of histone 3 lysine 9 (H3K9me2 and 3) of the muscle-selective gene promoters. Conversely, EHMT1 expression positively regulates the BAT-selective thermogenic program by stabilizing the PRDM16 protein. Notably, adipose-specific deletion of EHMT1 leads to a marked reduction of BAT-mediated adaptive thermogenesis, obesity and systemic insulin resistance. These data indicate that EHMT1 is an essential enzymatic switch that controls brown adipose cell fate and energy homeostasis.

Roles of Gut-Derived Secretory Factors in the Pathogenesis of Non-Alcoholic Fatty Liver Disease and Their Possible Clinical Applications.

The rising prevalence of non-alcoholic fatty liver disease (NAFLD) parallels the global increase in the number of people diagnosed with obesity and metabolic syndrome. The gut-liver axis (GLA) plays an important role in the pathogenesis of NAFLD/non-alcoholic steatohepatitis (NASH). In this review, we discuss the clinical significance and underlying mechanisms of action of gut-derived secretory factors in NAFLD/NASH, focusing on recent human studies. Several studies have identified potential causal associations between gut-derived secretory factors and NAFLD/NASH, as well as the underlying mechanisms. The effects of gut-derived hormone-associated drugs, such as glucagon-like peptide-1 analog and recombinant variant of fibroblast growth factor 19, and other new treatment strategies for NAFLD/NASH have also been reported. A growing body of evidence highlights the role of GLA in the pathogenesis of NAFLD/NASH. Larger and longitudinal studies as well as translational research are expected to provide additional insights into the role of gut-derived secretory factors in the pathogenesis of NAFLD/NASH, possibly providing novel markers and therapeutic targets in patients with NAFLD/NASH.

Westernization of lifestyle affects quantitative and qualitative changes in adiponectin.

BACKGROUND: Although Japanese-Americans and native Japanese share the same genetic predispositions, they live different lifestyles, resulting in insulin resistance in Japanese-Americans. We investigated whether the quantitative and qualitative changes in adiponectin (APN) due to differences in lifestyle contribute to the development of insulin resistance. METHODS: We evaluated 325 native Japanese in Hiroshima, Japan and 304 Japanese-Americans in Los Angeles, the United States, who were aged between 30 and 70 years and underwent medical examinations between 2009 and 2010. All participants underwent a 75-g oral glucose tolerance test (OGTT) to assess their glucose tolerance. The insulin response to oral glucose load, the Matsuda index, total APN levels, and C1q-APN/total-APN ratios were compared between native Japanese and Japanese-Americans. RESULTS: Compared with the native Japanese, the Japanese-Americans had significantly lower Matsuda index and higher area under the curve values for serum insulin concentration during OGTT in the normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) groups, but not in the diabetes mellitus (DM) group. Furthermore, the Japanese-Americans had significantly lower total APN levels and higher C1q-APN/total-APN ratios than the native Japanese in the NGT and IGT groups, but not in the DM group. CONCLUSIONS: This study suggested that, in Japanese people, the westernization of their lifestyle might affect quantitative and qualitative changes in APN and induce insulin resistance.

Mosapride citrate improves nonalcoholic steatohepatitis with increased fecal lactic acid bacteria and plasma glucagon-like peptide-1 level in a rodent model.

Several lines of evidence have suggested a role of gut microbiota in the etiology of nonalcoholic steatohepatitis (NASH). NASH subjects reportedly showed a prolonged orocecal transit time coexistent with small intestinal bacterial overgrowth. We considered the possibility that enhanced gastrointestinal motility would influence gut microbiota and thus investigated the effects of the gastroprokinetic agent mosapride citrate (MC) on gut microbiota and the development of NASH using a methionine-choline deficient (MCD) diet-fed rodent model. Mice were divided into three groups, given the normal chow diet (NCD), the MCD diet, or the MCD diet containing 10 mg·kg(-1)·day(-1) of MC (MCD plus MC) for 6 wk. NASH development was evaluated based on hepatic histochemical findings, serum parameters and various mRNA and/or protein expression levels. MC treatment suppressed MCD diet-induced NASH development, with reduced serum lipopolysaccharide and increased plasma glucagon-like peptide-1 (GLP-1) concentrations. Calculation of the relative abundance of each strain based on gut microbiota analyses indicated lactic acid bacteria specifically, such as Bifidobacterium and Lactobacillus, in feces to be decreased in the MCD, compared with the NCD group. Interestingly, the reduction in lactic acid bacteria in the MCD diet group was reversed in the MCD plus MC group. In addition, colon inflammation observed in the MCD diet group was reduced in the MCD plus MC group. Therefore, MC showed a protective effect against MCD diet-induced NASH development in our rodent model, with possible involvements of increased fecal lactic acid bacteria, protection against colon inflammation and elevated plasma GLP-1.

Detraining after short-term exercise induces hyperphagia and obesity with fatty liver and brown adipose tissue whitening in young male OLETF rats.

This study examined the effects of exercise and detraining at a young age on fat accumulation in various organs. Four-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF) rats were assigned to either the non-exercise sedentary (OLETF Sed) or exercise groups. The exercise group was subdivided into two groups: exercise between 4 and 12 weeks of age (OLETF Ex) and exercise between 4 and 6 weeks of age followed by non-exercise between 6 and 12 weeks of age (OLETF DT). Body weight was significantly lower in the OLETF Ex group than in the OLETF Sed group at 12 weeks of age. Fat accumulation in the epididymal white adipose tissue, liver, and brown adipose tissue was suppressed in the OLETF Ex group. During the exercise period, body weight and food intake in the OLETF DT group were significantly lower than those in the OLETF Sed group. However, food intake was significantly higher in the OLETF DT group than in the OLETF Sed group after exercise cessation, resulting in extreme obesity with fatty liver and brown adipose tissue whitening. Detraining after early-onset exercise promotes hyperphagia, causing extreme obesity. Overeating should be avoided during detraining periods in cases of exercise cessation at a young age.

Clinical Features of Tachycardia-induced Cardiomyopathy in Patients with Atrial Fibrillation.

Objective Atrial fibrillation (AF) is the most common cause of tachycardia-induced cardiomyopathy (TIC). However, which patients with AF are prone to developing TIC remains unclear. In this study, we investigated the clinical features of AF patients with TIC. Methods This single-center study included 722 patients with AF (average age, 63.1±10.2 years old; 191 women) who underwent radiofrequency catheter ablation. We defined TIC as an initial left ventricular ejection fraction (LVEF) of <40% and a >20% recovery of the LVEF after successful AF ablation and compared the clinical characteristics between the TIC and control groups. Results The proportions of type 2 diabetes (30.5% vs. 14.7%), renal dysfunction (34.2% vs. 23.8%), hypertension (67.1% vs. 54.8%), and persistent AF (62.2% vs. 32.2%) were significantly higher in the TIC group (n=82) than in the control group (n=640). The atrioventricular nodal effective refractory period (AVNERP) (303±72 ms vs. 332±86 ms; p=0.017) was significantly shorter in the TIC group than in the control group. A multivariable analysis found that persistent AF [odds ratio (OR), 3.19; 95% confidence interval (CI), 1.94-5.24], renal dysfunction (OR, 1.87; 95% CI, 1.06-3.32), and type 2 diabetes (OR, 2.30; 95% CI, 1.31-4.05) were significantly associated with TIC. Conclusion Comorbid renal dysfunction and type 2 diabetes were clinical features of AF patients with TIC. Persistent AF, and short AVNERP may be involved in the development of TIC.

Relationship between radiation dose and markers of insulin resistance and inflammation in atomic bomb survivors.

CONTEXT: In recent studies of childhood cancer survivors, diabetes has been considered a late effect associated with high therapeutic doses of radiation therapy. Our recent study of atomic bomb (A-bomb) survivors also suggested an association between radiation dose and diabetes incidence, with exposure city and age at exposure as radiation dose effect modifiers. Insulin resistance mediated by systemic inflammation and abnormal body composition has been suggested as a possible primary mechanism for the incidence of diabetes after total body irradiation, however, no studies have examined low-to- moderate radiation exposure (<4 Gy) and insulin resistance in A-bomb survivors. OBJECTIVES: To examine the association between radiation dose and markers of inflammation and insulin resistance. METHODS: This study investigated 3,152 survivors who underwent a health examination between 2008 and 2012 and who were younger than 15 years at exposure. Multivariate linear regression analyses were used to evaluate the radiation effects on levels of markers of inflammation and insulin resistance. RESULTS: Radiation dose was significantly and positively associated with levels of CRP, triglycerides, homeostasis model assessment of ß-cell function (HOMA-ß), and HOMA of insulin resistance (HOMA-IR) after adjustment for relevant covariates including sex, city, and age at exposure. Adiponectin and HDL cholesterol levels were also associated significantly and negatively with radiation dose. However, city was not a dose modifier of the radiation response on these markers of inflammation and insulin resistance. CONCLUSIONS: Insulin resistance might be a possible factor in the radiation related diabetes incidence in the A-bomb survivors.

Immunoprecipitation with an Anti-Epitope Tag Affinity Gel to Study Protein-Protein Interactions.

Protein-protein interactions (PPIs) play a pivotal role in biological phenomena, such as cellular organization, intracellular signal transduction, and transcriptional regulation. Therefore, understanding PPIs is an important starting point for further investigation of the function of the target protein. In this study, we propose a simple method to determine the binding of two target proteins by introducing mammalian expression vectors into HEK-293 cells using the polyethylenimine method, lysing the cells in homemade protein lysis buffer, and pulling down the target proteins on an epitope tag affinity gel. In addition, the PPI between the various epitope tag fused proteins can be confirmed by using affinity antibodies against each tag instead of the epitope tag affinity gel. This protocol could also be used to verify various PPIs, including nuclear extracts, from other cell lines. Therefore, it can be used as a basic method in a variety of PPI experiments. Proteins degrade by extended time course and repeated freeze-thaw cycles. Therefore, cell lysis, immunoprecipitation, and immunoblotting should be performed as seamlessly as possible.

Primary Aldosteronism and Risk of Cardiovascular Outcomes: Genome-Wide Association and Mendelian Randomization Study.

BACKGROUND: Observational studies have reported associations between primary aldosteronism (PA) and cardiovascular outcomes, including coronary artery diseases (CAD), congestive heart failure (CHF), and stroke. However, establishing causality remains a challenge due to the lack of randomized controlled trial data on this topic. We thus aimed to investigate the causal relationship between PA and the risk of developing CAD, CHF, and stroke. METHODS AND RESULTS: Cross-ancestry meta-analysis of genome-wide association studies combining East Asian and European ancestry (1560 PA cases and 742 139 controls) was conducted to identify single-nucleotide variants that are associated with PA. Then, using the identified genetic variants as instrumental variables, we conducted the 2-sample Mendelian randomization analysis to investigate the causal relationship between PA and incident CAD, CHF, and stroke among both East Asian and European ancestry. Summary association results were extracted from large genome-wide association studies consortia. Our cross-ancestry meta-analysis of East Asian and European populations identified 7 genetic loci significantly associated with the risk of PA, for which the genes nearest to the lead variants were CASZ1, WNT2B, HOTTIP, LSP1, TBX3, RXFP2, and NDP. Among the East Asian population, the pooled odds ratio estimates using these 7 genetic instruments of PA were 1.07 (95% CI, 1.03-1.11) for CAD, 1.10 (95% CI, 1.01-1.20) for CHF, and 1.13 (95% CI, 1.09-1.18) for stroke. The results were consistent among the European population. CONCLUSIONS: Our 2-sample Mendelian randomization study revealed that PA had increased risks of CAD, CHF, and stroke. These findings highlight that early and active screening of PA is critical to prevent future cardiovascular events.

Role of Pin1 protein in the pathogenesis of nonalcoholic steatohepatitis in a rodent model.

Nonalcoholic steatohepatitis (NASH) is a disorder characterized by simultaneous fat accumulation and chronic inflammation in the liver. In this study, Pin1 expression was revealed to be markedly increased in the livers of mice with methionine choline-deficient (MCD) diet-induced NASH, a rodent model of NASH. In addition, Pin1 KO mice were highly resistant to MCD-induced NASH, based on a series of data showing simultaneous fat accumulation, chronic inflammation, and fibrosis in the liver. In terms of Pin1-induced fat accumulation, it was revealed that the expression levels of peroxisome proliferator-activated receptor α and its target genes were higher in the livers of Pin1 KO mice than in controls. Thus, resistance of Pin1 KO mice to hepatic steatosis is partially attributable to the lack of Pin1-induced down-regulation of peroxisome proliferator-activated receptor α, although multiple other mechanisms are apparently involved. Another mechanism involves the enhancing effect of hematopoietic Pin1 on the expressions of inflammatory cytokines such as tumor necrosis factor and monocyte chemoattractant protein 1 through NF-κB activation, eventually leading to hepatic fibrosis. Finally, to distinguish the roles of hematopoietic or nonhematopoietic Pin1 in NASH development, mice lacking Pin1 in either nonhematopoietic or hematopoietic cells were produced by bone marrow transplantation between wild-type and Pin1 KO mice. The mice having nonhematopoietic Pin1 exhibited fat accumulation without liver fibrosis on the MCD diet. Thus, hepatic Pin1 appears to be directly involved in the fat accumulation in hepatocytes, whereas Pin1 in hematopoietic cells contributes to inflammation and fibrosis. In summary, this is the first study to demonstrate that Pin1 plays critical roles in NASH development. This report also raises the possibility that hepatic Pin1 inhibition to the appropriate level might provide a novel therapeutic strategy for NASH.

Integrator complex plays an essential role in adipose differentiation.

The dynamic process of adipose differentiation involves stepwise expressions of transcription factors and proteins specific to the mature fat cell phenotype. In this study, it was revealed that expression levels of IntS6 and IntS11, subunits of the Integrator complex, were increased in 3T3-L1 cells in the period when the cells reached confluence and differentiated into adipocytes, while being reduced to basal levels after the completion of differentiation. Suppression of IntS6 or IntS11 expression using siRNAs in 3T3-L1 preadipocytes markedly inhibited differentiation into mature adipocytes, based on morphological findings as well as mRNA analysis of adipocyte-specific genes such as Glut4, perilipin and Fabp4. Although Pparγ2 protein expression was suppressed in IntS6 or IntS11-siRNA treated cells, adenoviral forced expression of Pparγ2 failed to restore the capacity for differentiation into mature adipocytes. Taken together, these findings demonstrate that increased expression of Integrator complex subunits is an indispensable event in adipose differentiation. Although further study is necessary to elucidate the underlying mechanism, the processing of U1, U2 small nuclear RNAs may be involved in cell differentiation steps.

Selective activation of PPARα maintains thermogenic capacity of beige adipocytes.

Beige adipocytes are inducible thermogenic adipocytes used for anti-obesity treatment. Beige adipocytes rapidly lose their thermogenic capacity once external cues are removed. However, long-term administration of stimulants, such as PPARγ and ß-adrenergic receptor agonists, is unsuitable due to various side effects. Here, we reported that PPARα pharmacological activation was the preferred target for maintaining induced beige adipocytes. Pemafibrate used in clinical practice for dyslipidemia was developed as a selective PPARα modulator (SPPARMα). Pemafibrate administration regulated the thermogenic capacity of induced beige adipocytes, repressed body weight gain, and ameliorated impaired glucose tolerance in diet-induced obese mouse models. The transcriptome analysis revealed that the E-twenty-six transcription factor ELK1 acted as a cofactor of PPARα. ELK1 was mobilized to the Ucp1 transcription regulatory region with PPARα and modulated its expression by pemafibrate. These results suggest that selective activation of PPARα by pemafibrate is advantageous to maintain the function of beige adipocytes.

Peptidyl-prolyl cis/trans isomerase NIMA-interacting 1 associates with insulin receptor substrate-1 and enhances insulin actions and adipogenesis.

Peptidyl-prolyl cis/trans isomerase NIMA-interacting 1 (Pin1) is a unique enzyme that associates with the pSer/Thr-Pro motif and catalyzes cis-trans isomerization. We identified Pin1 in the immunoprecipitates of overexpressed IRS-1 with myc and FLAG tags in mouse livers and confirmed the association between IRS-1 and Pin1 by not only overexpression experiments but also endogenously in the mouse liver. The analysis using deletion- and point-mutated Pin1 and IRS-1 constructs revealed the WW domain located in the N terminus of Pin1 and Ser-434 in the SAIN (Shc and IRS-1 NPXY binding) domain of IRS-1 to be involved in their association. Subsequently, we investigated the role of Pin1 in IRS-1 mediation of insulin signaling. The overexpression of Pin1 in HepG2 cells markedly enhanced insulin-induced IRS-1 phosphorylation and its downstream events: phosphatidylinositol 3-kinase binding with IRS-1 and Akt phosphorylation. In contrast, the treatment of HepG2 cells with Pin1 siRNA or the Pin1 inhibitor Juglone suppressed these events. In good agreement with these in vitro data, Pin1 knock-out mice exhibited impaired insulin signaling with glucose intolerance, whereas adenoviral gene transfer of Pin1 into the ob/ob mouse liver mostly normalized insulin signaling and restored glucose tolerance. In addition, it was also demonstrated that Pin1 plays a critical role in adipose differentiation, making Pin1 knock-out mice resistant to diet-induced obesity. Importantly, Pin1 expression was shown to be up-regulated in accordance with nutrient conditions such as food intake or a high-fat diet. Taken together, these observations indicate that Pin1 binds to IRS-1 and thereby markedly enhances insulin action, essential for adipogenesis.

Valsartan, independently of AT1 receptor or PPARγ, suppresses LPS-induced macrophage activation and improves insulin resistance in cocultured adipocytes.

Macrophages are integrated into adipose tissues and interact with adipocytes in obese subjects, thereby exacerbating adipose insulin resistance. This study aimed to elucidate the molecular mechanism underlying the insulin-sensitizing effect of the angiotensin II receptor blocker (ARB) valsartan, as demonstrated in clinical studies. Insulin signaling, i.e., insulin receptor substrate-1 and Akt phosphorylations, in 3T3-L1 adipocytes was impaired markedly by treatment with tumor necrosis factor-α (TNFα) or in the culture medium of lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages, and valsartan had no effects on these impairments. However, in contrast, when cocultured with RAW 264.7 cells using a transwell system, the LPS-induced insulin signaling impairment in 3T3-L1 adipocytes showed almost complete normalization with coaddition of valsartan. Furthermore, valsartan strongly suppressed LPS-induced productions of cytokines such as interleukin (IL)-1ß, IL-6, and TNFα with nuclear factor-κB activation and c-Jun NH(2)-terminal kinase phosphorylation in RAW 264.7 and primary murine macrophages. Very interestingly, this effect of valsartan was also observed in THP-1 cells treated with angiotensin II type 1 (AT1) siRNA or a peroxisome proliferator-activated receptor-γ (PPARγ) antagonist as well as macrophages from AT1a receptor-knockout mice. We conclude that valsartan suppresses the inflammatory response of macrophages, albeit not via PPARγ or the AT1a receptor. This suppression appears to secondarily improve adipose insulin resistance.

Effects of long-term childhood exercise and detraining on lipid accumulation in metabolic-related organs.

The preventive effects of regular exercise on obesity-related health problems are carried over to the non-exercise detraining period, even when physical activity decreases with aging. However, it remains unknown whether regular childhood exercises can be carried over to adulthood. Therefore, this study aimed to investigate the effects of long-term childhood exercise and detraining on lipid accumulation in organs to prevent obesity in adulthood. Four-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF) rats were used as obese animals. OLETF rats were allocated into sedentary and exercise groups: exercise from 4- to 12-week-old and detraining from 12- to 20-week-old. At 12-week-old immediately after the exercise period, regular exercise completely inhibited hyperphagia, obesity, enlarged pancreatic islets, lipid accumulation and lobular inflammation in the liver, hypertrophied adipocytes in the white adipose tissue (WAT), and brown adipose tissue (BAT) whitening in OLETF rats. Additionally, exercise attenuated the decrease in the ratio of muscle wet weight to body weight associated with obesity. Decreased food consumption was maintained during the detraining period, which inhibited obesity and diabetes at 20-week-old after the detraining period. Histologically, childhood exercise inhibited the enlargement of pancreatic islets after the detraining period. In addition, inhibition of lipid accumulation was completely maintained in the WAT and BAT after the detraining period. However, the effectiveness was only partially successful in lipid accumulation and inflammation in the liver. The ratio of muscle wet weight to body weight was maintained after detraining. In conclusion, early long-term regular exercise effectively prevents obesity and diabetes in childhood, and its effectiveness can be tracked later in life. The present study suggests the importance of exercise during childhood and adolescence to inhibit hyperphagia-induced lipid accumulation in metabolic-related organs in adulthood despite exercise cessation.

Dietary Vitamins A, C, and Potassium Intake Is Associated With Narrower Retinal Venular Caliber.

INTRODUCTION: The retinal vasculature, a surrogate for the systemic microvasculature, can be observed non-invasively, providing an opportunity to examine the effects of modifiable factors, such as nutrient intake, on microcirculation. We aimed to investigate the possible associations of dietary nutrient intake with the retinal vessel caliber. METHODS: In this cross-sectional study, a total of 584 participants in a medical survey of Japanese descendants living in Los Angeles in 2015 underwent a dietary assessment, fundus photographic examination, and comprehensive physical and blood examinations. Retinal vessel caliber was measured using fundus photographs with a semi-automated computer system and summarized as central retinal artery and vein equivalents (CRAE and CRVE). The association between dietary nutrient intake and retinal vessel caliber was analyzed using a multivariate linear regression model adjusted for two models including potential confounders. The first model was adjusted for age and sex. The second model was adjusted for age, sex, smoking status, body mass index, hypertension, diabetes, dyslipidemia, history of coronary heart disease, and history of stroke. RESULTS: After adjustment of potential confounders, compared to the quartile with the lowest intake, the difference in CRVE for the highest quartile was -5.33 µm [95% confidence interval (CI): -9.91 to -0.76, P for trend = 0.02] for vitamin A, -4.93 µm (95% CI: -9.54 to -0.32, P for trend = 0.02) for vitamin C and -3.90 µm (95% CI: -8.48 to 0.69, P for trend = 0.04) for potassium. CONCLUSIONS: A significant association was observed between higher vitamins A, C and potassium intakes and narrower retinal venular caliber.

Masticatory dysfunction in patients with diabetic neuropathy: A cross-sectional study.

INTRODUCTION: Chewing well is essential for successful diet therapy and control of blood glucose level in patients with diabetes. In addition, long-term hyperglycemia is a risk factor for microvascular complications, which are the main cause of morbidity and mortality in these patients. Hence, it is plausible that masticatory disorder may be relevant to diabetic microvascular complications which is caused by long-term hyperglycemia. The aim of this study was to investigate whether masticatory disorders are relevant to diabetic microvascular complications. METHODS: This cross-sectional study included 172 patients with type 2 diabetes who underwent educational hospitalization in the Department of Endocrinology and Diabetic Medicine, Hiroshima University Hospital, from April 2016 to March 2020. Masticatory efficiency was determined quantitatively by using the GLUCO SENSOR GS-Ⅱ. Multivariable linear regression models were constructed to examine which factors were related to masticatory efficiency. Statistical significance was defined as a two-sided p value of < 0.05. RESULTS: According to the bivariable analysis, masticatory efficiency was significantly correlated with duration of diabetes (p = 0. 049), number of remaining teeth (p < 0.0001), the number of moving teeth (p = 0.007) and condition of diabetic neuropathy (p < 0.0001). Moreover, the number of remaining teeth (p < 0.0001) and diabetic neuropathy (p = 0.007) remained significantly correlated with masticatory efficiency in the multivariable analysis. CONCLUSIONS: For the first time, we demonstrated that patients with type 2 diabetes who developed diabetic neuropathy had significantly reduced masticatory efficiency. Effective mastication is an important factor in successful diet therapy for diabetes. To prevent the progression of diabetic complications, especially in patients with diabetic neuropathy, it may be necessary to combine individualized therapies from dentists and nutritionists with consideration for the level of masticatory dysfunction.