Acetate derived from the intestinal tract has a critical role in maintaining skeletal muscle mass and strength in mice.

Acetate is a short-chain fatty acid (SCFA) that is produced by microbiota in the intestinal tract. It is an important nutrient for the intestinal epithelium, but also has a high plasma concentration and is used in the various tissues. Acetate is involved in endurance exercise, but its role in resistance exercise remains unclear. To investigate this, mice were administered either multiple antibiotics with and without oral acetate supplementation or fed a low-fiber diet. Antibiotic treatment for 2 weeks significantly reduced grip strength and the cross-sectional area (CSA) of muscle fiber compared with the control group. Intestinal concentrations of SCFAs were reduced in the antibiotic-treated group. Oral administration of acetate with antibiotics prevented antibiotic-induced weakness of skeletal muscle and reduced CSA of muscle fiber. Similarly, a low-fiber diet for 1 year significantly reduced the CSA of muscle fiber and fecal and plasma acetate concentrations. To investigate the role of acetate as an energy source, acetyl-CoA synthase 2 knockout mice were used. These mice had a shorter lifespan, reduced skeletal muscle mass and smaller CSA of muscle fiber than their wild type littermates. In conclusion, acetate derived from the intestinal microbiome can contribute to maintaining skeletal muscle performance.

Nutritional and metabolic control of germ cell fate through O-GlcNAc regulation.

Fate determination of primordial germ cells (PGCs) is regulated in a multi-layered manner, involving signaling pathways, epigenetic mechanisms, and transcriptional control. Chemical modification of macromolecules, including epigenetics, is expected to be closely related with metabolic mechanisms but the detailed molecular machinery linking these two layers remains poorly understood. Here, we show that the hexosamine biosynthetic pathway controls PGC fate determination via O-linked ß-N-acetylglucosamine (O-GlcNAc) modification. Consistent with this model, reduction of carbohydrate metabolism via a maternal ketogenic diet that decreases O-GlcNAcylation levels causes repression of PGC formation in vivo. Moreover, maternal ketogenic diet intake until mid-gestation affects the number of ovarian germ cells in newborn pups. Taken together, we show that nutritional and metabolic mechanisms play a previously unappreciated role in PGC fate determination.

Relationship between the magnitude of body mass index reductions and remission in patients with type 2 diabetes in real world settings: Analysis of nationwide patient registry in Japan (JDDM74).

AIMS: To determine the association between the magnitude of weight loss and incidence of remission according to baseline characteristics in patients with diabetes in clinical settings. METHODS: In total, 39 676 Japanese patients with type 2 diabetes aged ≥18 years with glycated haemoglobin (HbA1c) ≥6.5% and/or glucose-lowering drug prescription were identified from databases of specialists' clinics from 1989 and followed until September 2022. Remission was diagnosed as maintaining HbA1c <6.5% at least 3 months after cessation of a glucose-lowering drug. Factors associated with remission were evaluated by logistic regression analysis according to weight change in 1 year (i.e. ≥10%, 7.0-9.9%, 3.0-6.9% reduction, <3% change and ≥3.0% increase). RESULTS: During the study period, 3454 remissions occurred. The rates of remission were higher in the group with the greatest reduction of body mass index (BMI) in any category examined (i.e. baseline BMI, HbA1c, duration of diabetes and treatment). The incidences of remission per 1000 person-years were about 25 and 50, respectively, for those with BMI ≥22.5 and reductions in BMI of 7.0-9.9% and ≥10% in 1 year. Remissions per 1000 person-years were 99.2 and 91.8, respectively, for those with baseline HbA1c of 6.5-6.9 and a 10% BMI reduction and those not taking glucose-lowering drugs accompanied by a 10% BMI reduction. CONCLUSIONS: Modest weight losses of 3.0-7.9% were significantly associated with remission, but a minimum of 10% weight loss would be required in addition to an early diagnosis to achieve a 10% remission rate in clinical settings. Our results implied that remission may be expected with a relatively lower BMI in an Asian population compared with that was reported in Western populations if accompanied by weight loss.

O-linked N-acetylglucosamine modification is essential for physiological adipose expansion induced by high-fat feeding.

Adipose tissues accumulate excess energy as fat and heavily influence metabolic homeostasis. O-linked N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), which involves the addition of N-acetylglucosamine to proteins by O-GlcNAc transferase (Ogt), modulates multiple cellular processes. However, little is known about the role of O-GlcNAcylation in adipose tissues during body weight gain due to overnutrition. Here, we report on O-GlcNAcylation in mice with high-fat diet (HFD)-induced obesity. Mice with knockout of Ogt in adipose tissue achieved using adiponectin promoter-driven Cre recombinase (Ogt-FKO) gained less body weight than control mice under HFD. Surprisingly, Ogt-FKO mice exhibited glucose intolerance and insulin resistance, despite their reduced body weight gain, as well as decreased expression of de novo lipogenesis genes and increased expression of inflammatory genes, resulting in fibrosis at 24 weeks of age. Primary cultured adipocytes derived from Ogt-FKO mice showed decreased lipid accumulation. Both primary cultured adipocytes and 3T3-L1 adipocytes treated with OGT inhibitor showed increased secretion of free fatty acids. Medium derived from these adipocytes stimulated inflammatory genes in RAW 264.7 macrophages, suggesting that cell-to-cell communication via free fatty acids might be a cause of adipose inflammation in Ogt-FKO mice. In conclusion, O-GlcNAcylation is important for healthy adipose expansion in mice. Glucose flux into adipose tissues may be a signal to store excess energy as fat.NEW & NOTEWORTHY We evaluated the role of O-GlcNAcylation in adipose tissue in diet-induced obesity using adipose tissue-specific Ogt knockout mice. We found that O-GlcNAcylation in adipose tissue is essential for healthy fat expansion and that Ogt-FKO mice exhibit severe fibrosis upon long-term overnutrition. O-GlcNAcylation in adipose tissue may regulate de novo lipogenesis and free fatty acid efflux to the degree of overnutrition. We believe that these results provide new insights into adipose tissue physiology and obesity research.

Incidence and predictors of remission and relapse of type 2 diabetes mellitus in Japan: Analysis of a nationwide patient registry (JDDM73).

AIMS: To determine the incidence of remission and 1-year relapse from remission and associated factors in patients with type 2 diabetes. MATERIALS AND METHODS: A total of 48 320 Japanese patients with type 2 diabetes aged ≥18 years, with glycated haemoglobin (HbA1c) levels ≥48 mmol/mol (6.5%) and/or glucose-lowering drug prescription, were identified from databases of specialist clinics from 1989 and followed until September 2022. Remission was defined as HbA1c <48 mmol/mol at least 3 months after cessation of a glucose-lowering drug. Relapse was defined as failure to maintain remission for 1 year. Factors associated with remission and relapse were evaluated by logistic regression analysis. RESULTS: The overall incidence of remissions per 1000 person-years was 10.5, and for those with HbA1c levels of 48 to 53 mmol/mol (6.5% to 6.9%), those taking no glucose-lowering drugs at baseline, and those with a ≥10% body mass index (BMI) reduction in 1 year, it was 27.8, 21.7 and 48.2, respectively. Shorter duration, lower baseline HbA1c, higher baseline BMI, higher BMI reduction at 1 year, and no glucose-lowering drugs at baseline were significantly associated with remission. Among 3677 persons with remission, approximately two-thirds (2490) relapsed within 1 year. Longer duration, lower BMI at baseline, and lower BMI reduction at 1 year were significantly associated with relapse. CONCLUSIONS: The results showed that the incidence of remission and predictors of relapse, especially baseline BMI, might differ greatly between East Asian and Western populations. Furthermore, the relationships of BMI reduction with remission and relapse may be greater in East Asian than in Western populations, implying ethnic differences in returning from overt hyperglycaemia to nearly normal glucose levels.

A family with type A insulin resistance syndrome caused by a novel insulin receptor mutation.

Summary: A 17-year-old boy was referred to our endocrinology clinic for a clinical investigation of hyperinsulinemia. An oral glucose tolerance test showed plasma glucose concentrations in the normal range. However, insulin concentrations were considerably elevated (0 min: 71 µU/mL; 60 min: 953 µU/mL), suggesting severe insulin resistance. An insulin tolerance test confirmed that he had insulin resistance. There was no apparent hormonal or metabolic cause, including obesity. The patient had no outward features of hyperinsulinemia, including acanthosis nigricans or hirsutism. However, his mother and grandfather also had hyperinsulinemia. Genetic testing showed that the patient (proband), his mother, and his grandfather had a novel p.Val1086del heterozygous mutation in exon 17 of the insulin receptor gene (INSR). Although all three family members have the same mutation, their clinical courses have been different. The onset of the mother's diabetes was estimated at 50 years, whereas the grandfather developed diabetes at 77 years. Learning points: Type A insulin resistance syndrome is caused by mutations in the insulin receptor (INSR) gene and results in severe insulin resistance. Genetic evaluation should be considered in adolescents or young adults with dysglycemia when an atypical phenotype, such as severe insulin resistance, or a relevant family history is observed. Clinical courses may differ even if the same genetic mutation is found in a family.

Reduced incidence of cardiovascular disease in patients with type 2 diabetes through the integrated improvement of diabetes care by comparing two prospective observational cohorts in real-world clinical practice (JDDM 72).

AIM: To investigate whether any reduction in all-cause mortality and cardiovascular disease morbidity was found over the decade in type 2 diabetes on real-world practice. METHODS: A prospective observational study was performed by following two independent cohorts recruited in 2004 (n = 3286, Cohort 1) and 2014 (n = 3919, Cohort 2). The primary outcome was a composite of onset of cardiovascular disease and death. Cox proportional hazards analysis was used to explore any difference between Cohort 2 and Cohort 1 for the composite endpoints and cardiovascular disease after adjustment for covariates and accumulation of five risks (smoking, HbA1c, blood pressure, lipids, and albuminuria) outside target ranges. RESULTS: During the 8-year follow-up, 391 (11.9%) and 270 (6.9%) primary outcomes, and 270 (8.2%) and 161 (4.1%) cardiovascular diseases occurred in Cohort 1 and Cohort 2, respectively. Cohort 2 (vs. Cohort 1) exhibited a significant risk reduction for composite endpoints (HR 0.73, 95% CI 0.62 to 0.86) and cardiovascular disease (HR 0.64, 95% CI 0.52 to 0.79), and similarly exhibited a significant reduction independent of the accumulation of the five risks. CONCLUSIONS: The significant reduction of Cohort 2 for cardiovascular disease independent of the baseline covariates suggests an integrated effect delivered by the recent treatment advances.

Ketone bodies: A double-edged sword for mammalian life span.

Accumulating evidence suggests health benefits of ketone bodies, and especially for longevity. However, the precise role of endogenous ketogenesis in mammalian life span, and the safety and efficacy of the long-term exogenous supplementation of ketone bodies remain unclear. In the present study, we show that a deficiency in endogenous ketogenesis, induced by whole-body Hmgcs2 deletion, shortens life span in mice, and that this is prevented by daily ketone body supplementation using a diet containing 1,3-butanediol, a precursor of ß-hydroxybutyrate. Furthermore, feeding the 1,3-butanediol-containing diet from early in life increases midlife mortality in normal mice, but in aged mice it extends life span and prevents the high mortality associated with atherosclerosis in ApoE-deficient mice. By contrast, an ad libitum low-carbohydrate ketogenic diet markedly increases mortality. In conclusion, endogenous ketogenesis affects mammalian survival, and ketone body supplementation may represent a double-edged sword with respect to survival, depending on the method of administration and health status.

Annual trends in glycemic control and prescribing patterns in diabetic treatment according to age in Japanese patients with type 2 diabetes between 2012 and 2019 (JDDM 71).

AIMS: This study aimed to evaluate changes in glycemic control and diabetes treatment by age group in Japanese patients with type 2 diabetes. METHODS: The study included the results of approximately 40,000 patients/year using cross-sectional and retrospective analyses from 2012 to 2019. RESULTS: There was little change in the glycemic control status in all age groups during the study period. However, by age group, patients aged ≤ 44 years continued to have the highest glycated hemoglobinA1c (HbA1c) values during the study period (7.4 % ± 1.7 % in 2012 and 7.4 % ± 1.5 % in 2019), especially in insulin-treated patients (8.3 % ± 1.9 % in 2012 and 8.4 % ± 1.8 % in 2019). Biguanides and dipeptidyl peptidase-4 inhibitors were widely prescribed. Sulfonylurea and insulin use showed a decreasing trend, but older patients had a higher percentage of prescriptions. Sodium glucose transporter 2 inhibitors were prescribed rapidly, especially in younger patients. CONCLUSIONS: There were no obvious changes in glycemic control over time in the study period. The mean HbA1c level was higher in younger patients, which suggested that improvement is required. In older patients, there was a trend toward greater emphasis on management to avoid hypoglycemia. Different treatment strategies based on age showed different drug choices.

Coexistence of Pheochromocytoma and Primary Aldosteronism due to Multiple Aldosterone-producing Micronodules in the Ipsilateral Adrenal Gland.

A 46-year-old woman was referred for hypertension and a right adrenal tumor. Primary aldosteronism (PA) was suspected because of the high plasma aldosterone concentration-to-plasma renin activity ratio. However, a subsequent evaluation revealed coexistent PA and pheochromocytoma. We performed laparoscopic right adrenalectomy. Histology of the resected adrenal gland confirmed pheochromocytoma and multiple aldosterone-producing adrenocortical micronodules. Following adrenalectomy, the urinary catecholamine levels normalized, and hyperaldosteronism improved but persisted. Hypertension also improved but persisted and was normalized with spironolactone. The clinical course indicated that the PA lesions were likely bilateral. This was a histologically proven case of coexistent pheochromocytoma and PA due to multiple aldosterone-producing micronodules.

Changes in prescription patterns and doses of oral antidiabetic drugs in Japanese patients with type 2 diabetes (JDDM70).

We assessed the prescription patterns of oral antidiabetic drugs in Japanese patients with type 2 diabetes between 2002 and 2020 using data from the Computerized Diabetes Care database. Among 172,960 patients treated with oral antidiabetic drugs, both the sulfonylurea prescription rate and dose decreased from 2002 to 2020. Prescriptions of biguanides, dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter 2 inhibitors increased; their dose and dose frequency remained relatively stable. Trends in oral antidiabetic drug prescriptions changed over time, reflecting guideline recommendations and existing evidence.

Real-world evidence of the impact of obesity on residual teeth in the Japanese population: A cross-sectional study.

BACKGROUND: Tooth loss is associated with nutritional status and significantly affects quality of life, particularly in older individuals. To date, several studies reveal that a high BMI is associated with tooth loss. However, there is a lack of large-scale studies that examined the impact of obesity on residual teeth with respect to age and tooth positions. OBJECTIVE: We assessed the impact of obesity on the number and position of residual teeth by age groups using large scale of Japanese database. METHODS: This was a cross-sectional study of 706150 subjects that were included in the database that combined the data from health insurance claims and health check-up, those lacking information about BMI, HbA1c level, smoking status, and the number of residual teeth were excluded. Thus, a total of 233517 aged 20-74 years were included. Subjects were classified into 4 categories based on BMI, and the number of teeth was compared between age-groups. The percentage of subjects with residual teeth in each position was compared between groups with obesity (BMI ≥25.0 kg/m2) and non-obesity. Logistic regression analysis was performed to clarify whether obesity predicts having <24 teeth. RESULTS: Higher BMI was associated with fewer teeth over 40s (P for trend <0.0001 when <70s). Obesity was associated with the reduction of residual teeth in the maxillary; specifically, the molars were affected over the age 30. Smoking status further affected tooth loss at positions that were not affected by obesity alone. After adjusting for age, sex, smoking status, and HbA1c ≥6.5%, obesity remained an independent predictive factor for having <24 teeth (ORs: 1.35, 95% CIs: 1.30-1.40). CONCLUSIONS: We found that an increase in BMI was associated with a decrease in the number of residual teeth from younger ages independently of smoking status and diabetes in the large scale of Japanese database.

Interconnection between cardiovascular, renal and metabolic disorders: A narrative review with a focus on Japan.

Insights from epidemiological, clinical and basic research are illuminating the interplay between metabolic disorders, cardiovascular disease (CVD) and kidney dysfunction, termed cardio-renal-metabolic (CRM) disease. Broadly defined, CRM disease involves multidirectional interactions between metabolic diseases such as type 2 diabetes (T2D), various types of CVD and chronic kidney disease (CKD). T2D confers increased risk for heart failure, which-although well known-has only recently come into focus for treatment, and may differ by ethnicity, whereas atherosclerotic heart disease is a well-established complication of T2D. Many people with T2D also have CKD, with a higher risk in Asians than their Western counterparts. Furthermore, CVD increases the risk of CKD and vice versa, with heart failure, notably, present in approximately half of CKD patients. Molecular mechanisms involved in CRM disease include hyperglycaemia, insulin resistance, hyperactivity of the renin-angiotensin-aldosterone system, production of advanced glycation end-products, oxidative stress, lipotoxicity, endoplasmic reticulum stress, calcium-handling abnormalities, mitochondrial malfunction and deficient energy production, and chronic inflammation. Pathophysiological manifestations of these processes include diabetic cardiomyopathy, vascular endothelial dysfunction, cardiac and renal fibrosis, glomerular hyperfiltration, renal hypoperfusion and venous congestion, reduced exercise tolerance leading to metabolic dysfunction, and calcification of atherosclerotic plaque. Importantly, recognition of the interaction between CRM diseases would enable a more holistic approach to CRM care, rather than isolated treatment of individual conditions, which may improve patient outcomes. Finally, aspects of CRM diseases may differ between Western and East Asian countries such as Japan, a super-ageing country, with potential differences in epidemiology, complications and prognosis that represent an important avenue for future research.

Association between Obesity and Intake of Different Food Groups among Japanese with Type 2 Diabetes Mellitus-Japan Diabetes Clinical Data Management Study (JDDM68).

BACKGROUND: We investigated the association between various food groups and obesity in Japanese patients with type 2 diabetes. METHODS: 2070 patients with type 2 diabetes who attended 26 diabetes clinics throughout Japan were analyzed and were divided into obese and non-obese groups. Intakes of food groups determined by a food frequency questionnaire were compared. Odds ratios for obesity for quartiles of individual food groups were calculated using a logistic regression model. RESULTS: Non-obese patients consumed a larger variety of food groups than obese patients, with the diets of non-obese individuals closer to the traditional Japanese diet characterized by fish, seaweed, and soybeans/soy products. Among 21 food groups, low vegetable intake and high sweets intake were the most strongly associated with obesity in both men and women. Low intake of both fruits and vegetables and the combination of high intake of sweets and low intake of fruits were associated with obesity. CONCLUSIONS: Food groups and their combinations that were strongly associated with obesity in Japanese patients with type 2 diabetes were identified. Our findings also suggested an inverse association between the traditional Japanese diet and obesity.

Eighteen-year trends in the management of patients with diabetes in the Shiga Diabetes Clinical Survey: overall trends and differences by age group.

Aim: To examine the trends in the management of patients with diabetes over an 18-year period in Japan. Participants and methods: We recorded the height, body mass, laboratory data, diabetes treatment, and screening status of diabetic complications from the data collected during the Shiga Diabetes Clinical Survey, which has been performed every 6 years since 2000. We then evaluated the management of patients with diabetes in Shiga Prefecture. The study included 17,870, 18,398, 24,243, and 26,624 participants in each of the 4 years of measurements. Results: The mean age and body mass index (BMI) of the participants gradually increased. The percentage of patients with BMI of ≥ 25 kg/m2 was higher in younger patients. Glycemic control significantly improved over 18 years (hemoglobin A1c: 7.3% ± 1.4% in 2000 to 7.1% ± 1.1% in 2018, P for trend < 0.001). The mean hemoglobin A1c levels were higher in younger patients than in elderly patients and increased from 2012 to 2018 in patients aged ≥ 65 years. The proportion of participants who underwent screening for albuminuria and diabetic retinopathy increased. The mean blood pressure and low-density lipoprotein cholesterol concentration decreased. Conclusions: Glycemic control has been maintained at an acceptable level since the previous survey. Although glycemic control has become less strict in elderly patients with diabetes, glycemic control is poorer in younger patients than in elderly patients. Obesity is an increasingly important problem, particularly in younger patients. The frequency of screening for diabetic complications and the control of blood pressure should be improved. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-022-00573-2.

The renoprotective effect of once-weekly GLP-1 receptor agonist dulaglutide on progression of nephropathy in Japanese patients with type 2 diabetes and moderate to severe chronic kidney disease (JDDM67).

AIMS/INTRODUCTION: Few studies have investigated the renoprotective effect of glucagon-like peptide-1 (GLP-1) receptor in patients with chronic kidney disease (CKD). This study evaluated the effect of dulaglutide 0.75 mg on renal function in Japanese patients with type 2 diabetes and CKD stage 3 to 4. MATERIALS AND METHODS: Dulaglutide (group A) and non-dulaglutide (group B) were compared using data collected from a computerized diabetes care database. For group B, propensity score weighting based on propensity scores was performed. Evaluation items were a change from baseline in hemoglobin A1c (HbA1c), body weight, urine albumin-to-creatinine ratio (UACR), and estimated glomerular filtration rate (eGFR), for 3 years. RESULTS: In total, the data obtained from 255 patients (125 and 130 patients for group A and B, respectively) were analyzed. Propensity score-adjusted patient background characteristics (group A vs B) were age 70.8 vs 69.4 years, body weight 70.2 vs 72.9 kg, body mass index 27.3 vs 28.1 kg/m2 , HbA1c 8.4 vs 8.5%, eGFR 47.9 vs 47.7 mL/min/1.73 m2 , and UACR 218 vs 251 mg/gCr. Although there were no statistically significant differences in the change from baseline between groups A and B at most time points in eGFR, a statistically significant eGFR decline in group B was observed in slope analysis for 3 years. This renoprotective effect was marked in patients with macro-albuminuria and/or concomitant SGLT2 inhibitor use. CONCLUSIONS: Dulaglutide slowed the eGFR decline in patients with type 2 diabetes and CKD stage 3 to 4.

Ketone body 3-hydroxybutyrate enhances adipocyte function.

Ketone bodies, including 3HBA, are endogenous products of fatty acid oxidation, and Hmgcs2 is the first rate-limiting enzyme of ketogenesis. From database analysis and in vivo and in vitro experiments, we found that adipose tissue and adipocytes express Hmgcs2, and that adipocytes produce and secrete 3HBA. Treatment with 3HBA enhanced the gene expression levels of the antioxidative stress factors, PPARγ, and lipogenic factors in adipose tissue in vivo and in adipocytes in vitro, accompanied by reduced ROS levels. Knockdown of endogenous Hmgcs2 in adipocytes markedly decreased 3HBA levels in adipocytes and decreased the gene expression levels of the antioxidative stress factors, PPARγ, and lipogenic factors with increased ROS levels. Conversely, overexpression of Hmgcs2 in adipocytes increased 3HBA secretion from adipocytes and enhanced the gene expression levels of the antioxidative stress factors, PPARγ, and lipogenic factors. These results demonstrate that 3HBA plays significant roles in enhancing the physiological function of adipocytes.

A Long-term Estimated Glomerular Filtration Rate Plot Analysis Permits the Accurate Assessment of a Decline in the Renal Function by Minimizing the Influence of Estimated Glomerular Filtration Rate Fluctuations.

Objective Evaluating the rate of decline in the estimated glomerular filtration rate (eGFR) may help identify patients with occult chronic kidney disease (CKD). We herein report that eGFR fluctuation complicates the assessment of the rate of decline and propose a long-term eGFR plot analysis as a solution. Methods In 142 patients with persistent eGFR decline in a single hospital, we evaluated the factors influencing the rate of eGFR decline, calculated over the long term (≥3 years) and short term (<3 years) using eGFR plots, taking into account eGFR fluctuation between visits. Results The difference between the rate of eGFR decline calculated using short- and long-term plots increased as the time period considered in the short-term plots became shorter. A regression analysis revealed that eGFR fluctuation was the only factor that explained the difference and that the fluctuation exceeded the annual eGFR decline in all participants. Furthermore, the larger the eGFR fluctuation, the more difficult it became to detect eGFR decline using a short-term eGFR analysis. Obesity, a high eGFR at baseline, and faster eGFR decline were associated with larger eGFR fluctuations. To circumvent the issue of eGFR fluctuation in the assessment of the rate of eGFR decline, we developed a system that generates a long-term eGFR plot using all eGFR values for a participant, which enabled the detection of occult CKD, facilitating early therapeutic intervention. Conclusion The construction of long-term eGFR plots is useful for identifying patients with progressive eGFR decline, as it minimizes the effect of eGFR fluctuation.

Effect of diabetes and prediabetes on the development of disability and mortality among middle-aged Japanese adults: A 22-year follow up of NIPPON DATA90.

AIMS/INTRODUCTION: To examine the association between diabetes and prediabetes at baseline, and disability, mortality over a 22-year period among middle-aged Japanese adults. MATERIALS AND METHODS: Participants consisted of 1,788 adults aged 45-64 years at baseline from the cohort study National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged 1990 (NIPPON DATA90). Disability, defined as having a decline in activities of daily living (ADL), was assessed by a modified Katz questionnaire at four time points. Disability and death without disability for 22-year follow up were used as outcomes to test the association with a diagnosis of diabetes or prediabetes at baseline, using multinomial logistic regression. Adjusted odds ratios (ORs) were obtained from four models that contained appropriate adjustment factors, such as age, sex, smoking status, drinking status, body mass index and cardiovascular risk factors (hypertension, hypercholesterolemia, triglycerides, low serum high-density lipoprotein), at baseline. RESULTS: In the present study, 334 participants (18.7%) reported at least one disability, and 350 (19.6%) were reported dead without observation of disability during follow up. Adjusting sex and other risk factors, participants with diabetes and prediabetes had a higher risk for disability (OR 1.43, 95% confidence interval [CI] 1.07-1.91 and OR 1.66, 95% CI 1.10-2.50, respectively) and for mortality (OR 1.56, 95% CI 1.16-2.08 and OR 1.77, 95% CI 1.18-2.65, respectively) than individuals with normal glucose tolerance. CONCLUSIONS: In middle-aged Japanese adults, individuals with diabetes and prediabetes were more likely to be associated with disability and mortality. Our findings suggest that prediabetes and diabetes in middle-aged adults should be paid more attention, and requires more intervention to prevent disability and mortality in later life.

Limited effects of systemic or renal lipoprotein lipase deficiency on renal physiology and diseases.

Lipoprotein lipase (LPL) is an enzyme that catalyzes the hydrolysis of circulating triglyceride and the transport of fatty acids into cells. Its activity is positively regulated by insulin, and insulin resistance is associated with low LPL activity and subsequent hypertriglyceridemia. The involvement of hypertriglyceridemia in chronic kidney disease (CKD) is still under the debate in a clinical setting. Therefore, we aimed to study the role of hypertriglyceridemia in the disease using mice with systemic or renal-specific LPL deficiency. Systemic LPL deficiency was characterized by hypertriglyceridemia, but not renal injury or dyslipidemia-related conditions, such as fatty liver. Furthermore, the LPL deficiency-induced hypertriglyceridemia was not associated with a worsening of the CKD phenotype or atherosclerosis, even when CKD was induced by 5/6 nephrectomy. Next, because LPL-mediated fatty acid uptake may be important for energy metabolism in proximal tubular epithelial cells (PTECs), the role of renal LPL in renal physiology was studied by generating mice lacking LPL specifically in PTECs. These mice showed no abnormalities in their histology or renal reabsorption of micro molecules. These findings suggest that systemic and renal lipid abnormalities caused by LPL deficiency do not cause or worsen the development of renal injury, and provide novel insight regarding the potential role of lipotoxicity in the pathogenesis of obesity-related kidney injury.