Sex differences in predictive factors for onset of type 2 diabetes in Japanese individuals: A 15-year follow-up study.

AIMS/INTRODUCTION: The increase in the number of patients with type 2 diabetes mellitus is an important concern worldwide. The goal of this study was to investigate factors involved in the onset of type 2 diabetes mellitus, and sex differences in long-term follow up of people with normal glucose tolerance. MATERIALS AND METHODS: Of 1,309 individuals who underwent screening at our facility in 2004, 748 individuals without diabetes were enrolled. Correlations of metabolic markers including serum adiponectin (APN) with onset of type 2 diabetes mellitus were examined over 15 years in these individuals. RESULTS: The Kaplan-Meier curve for onset of type 2 diabetes mellitus for 15 years in the decreased APN group was examined. Hazard ratios for the APN concentration for onset of diabetes were 1.78 (95% confidence interval [CI] 1.20-2.63, P = 0.004) in all participants, 1.48 (95% CI 0.96-2.29, P = 0.078) for men and 3.01 (95% CI 1.37-6.59, P = 0.006) for women. During the follow-up period of 15 years, body mass index, estimated glomerular filtration rate, fatty liver, C-reactive protein and alanine aminotransferase in men were significant in univariate analysis, but only estimated glomerular filtration rate and fatty liver were significantly related to onset of type 2 diabetes mellitus in multivariate analysis. In women, body mass index, systolic blood pressure, triglyceride, fatty liver and APN were significant in univariate analysis, and APN was the only significant risk factor in multivariate analysis (P < 0.05). CONCLUSIONS: There are differences between men and women with regard to targets for intervention to prevent the onset of type 2 diabetes mellitus. Individuals requiring intensive intervention should be selected with this finding to maximize the use of limited social and economic resources.

ß2-adrenergic receptor agonist counteracts skeletal muscle atrophy and oxidative stress in uremic mice.

In patients with chronic kidney disease, skeletal muscle dysfunction is associated with mortality. Uremic sarcopenia is caused by ageing, malnutrition, and chronic inflammation, but the molecular mechanism and potential therapeutics have not been fully elucidated yet. We hypothesize that accumulated uremic toxins might exert a direct deteriorative effect on skeletal muscle and explore the pharmacological treatment in experimental animal and culture cell models. The mice intraperitoneally injected with indoxyl sulfate (IS) after unilateral nephrectomy displayed an elevation of IS concentration in skeletal muscle and a reduction of instantaneous muscle strength, along with the predominant loss of fast-twitch myofibers and intramuscular reactive oxygen species (ROS) generation. The addition of IS in the culture media decreased the size of fully differentiated mouse C2C12 myotubes as well. ROS accumulation and mitochondrial dysfunction were also noted. Next, the effect of the ß2-adrenergic receptor (ß2-AR) agonist, clenbuterol, was evaluated as a potential treatment for uremic sarcopenia. In mice injected with IS, clenbuterol treatment increased the muscle mass and restored the tissue ROS level but failed to improve muscle weakness. In C2C12 myotubes stimulated with IS, although ß2-AR activation also attenuated myotube size reduction and ROS accumulation as did other anti-oxidant reagents, it failed to augment the mitochondrial membrane potential. In conclusion, IS provokes muscular strength loss (uremic dynapenia), ROS generation, and mitochondrial impairment. Although the ß2-AR agonist can increase the muscular mass with ROS reduction, development of therapeutic interventions for restoring skeletal muscle function is still awaited.

Hyperferritinemia Is a Predictor of Onset of Diabetes in Japanese Males Independently of Decreased Renal Function and Fatty Liver: A Fifteen-Year Follow-Up Study.

BACKGROUND: Type 2 diabetes is an important health concern worldwide. The disease etiology may depend on multiple environmental and genetic factors that cause insulin resistance, including dysregulation of iron storage. The goal of this study was to examine the relationship of the serum ferritin concentration with onset of diabetes over a long period. METHODS: Correlations of serum ferritin and metabolic markers with onset of diabetes mellitus were examined over 15 years in 150 males participating in a health screening program. RESULTS: HOMA-ß showed a gradual significant decrease in the first 4 years in subjects with ferritin > 190 ng/mL (group H) compared to those with ferritin ≤ 190 ng/mL, but there was no difference in HOMA-R between these groups. A significant number of cases with onset of diabetes was observed over 15 years (hazard ratio (HR): 3.97), and obesity, fasting blood glucose level, hemoglobin A1c (HbA1c), HOMA-R, fasting immunoreactive insulin (IRI) and C-peptide immunoreactivity (CPR) were all significant in univariate comparison between non-diabetes and diabetes-onset groups. In multivariate analysis, ferritin in group H (HR: 3.25), fatty liver (HR: 3.38), estimated glomerular filtration rate (eGFR) < 70 mL/min/1.73 m2 (HR: 3.48) and high-density lipoprotein (HDL) < 40 mg/dL (HR: 2.61) were significant predictive factors for onset of type 2 diabetes mellitus. CONCLUSIONS: These results suggest that the serum ferritin level is an important index for priority intervention in preventive medicine for reduction of onset of diabetes.

Mitochondrial Dysfunction in Kidney Disease and Uremic Sarcopenia.

Recently, there has been an increased focus on the influences of mitochondrial dysfunction on various pathologies. Mitochondria are major intracellular organelles with a variety of critical roles, such as adenosine triphosphate production, metabolic modulation, generation of reactive oxygen species, maintenance of intracellular calcium homeostasis, and the regulation of apoptosis. Moreover, mitochondria are attracting attention as a therapeutic target in several diseases. Additionally, a lot of existing agents have been found to have pharmacological effects on mitochondria. This review provides an overview of the mitochondrial change in the kidney and skeletal muscle, which is often complicated with sarcopenia and chronic kidney disease (CKD). Furthermore, the pharmacological effects of therapeutics for CKD on mitochondria are explored.

Uremic Sarcopenia: Clinical Evidence and Basic Experimental Approach.

Sustained physical activity extends healthy life years while a lower activity due to sarcopenia can reduce them. Sarcopenia is defined as a decrease in skeletal muscle mass and strength due not only to aging, but also from a variety of debilitating chronic illnesses such as cancer and heart failure. Patients with chronic kidney disease (CKD), who tend to be cachexic and in frail health, may develop uremic sarcopenia or uremic myopathy due to an imbalance between muscle protein synthesis and catabolism. Here, we review clinical evidence indicating reduced physical activity as renal function deteriorates and explore evidence-supported therapeutic options focusing on nutrition and physical training. In addition, although sarcopenia is a clinical concept and difficult to recapitulate in basic research, several in vivo approaches have been attempted, such as rodent subtotal nephrectomy representing both renal dysfunction and muscle weakness. This review highlights molecular mechanisms and promising interventions for uremic sarcopenia that were revealed through basic research. Extensive study is still needed to cast light on the many aspects of locomotive organ impairments in CKD and explore the ways that diet and exercise therapies can improve both outcomes and quality of life at every level.

Regional variance in the use of urine dipstick test for outpatients in Japan.

AIM: The urine dipstick is a simple diagnostic module for detecting proteinuria, haematuria and glycosuria and is favourably accepted in East Asia despite debates regarding its accuracy and target population, claiming that quantitative tests for a high-risk cohort should be more cost-effective. However, the current status of utilizing this test in these countries is not widely known due to lack of extensive data. We aimed to clarify the current nationwide and regional status of utilization of the urine dipstick test in an outpatient care setting and to determine the regional factors associated with adoption of this method. METHODS: This cross-sectional study used openly accessible data from the national claim database that included the health insurance claims data of the Japanese population in 2017. RESULTS: In total, 67 125 386 urine dipstick tests were performed compared with 1 862 700 quantitative urine protein tests and 17 544 949 urine sediment microscopy tests. Dipstick tests were employed principally for those who are >65 years old (60.3%) and, although the male population (52.5%) is generally larger, the female population is larger in age of 15 to 39 years and >85 years. Multivariate analysis with several regional parameters revealed that the test was performed more commonly in the areas that accommodate greater elderly population (P < .01). CONCLUSION: Despite a heated dispute, the urine dipstick test is performed even more frequently than the quantitative biochemical or microscopic sediment tests, especially in regions holding the larger elderly population, which suggests that the test forms a part of geriatric medical care.

IL-6-producing Renal Cell Carcinoma Causing Renal and Endocrine Paraneoplastic Syndromes.

An 83-year-old man with stable chronic kidney disease (CKD) exhibited a sudden increase in urinary N-acetyl-ß-D-glucosaminidase and protein excretion, suggesting aggravated kidney damage. Simultaneously, he lost diabetic control, requiring up to 54 units of insulin daily. A detailed examination revealed the presence of renal cell carcinoma, which was surgically resected and confirmed to be interleukin-6-positive by immunohistochemistry. Postoperatively, his uni-nephrectomy necessitated hemodialysis, but the patient's insulin resistance was ameliorated; no medication was required to control diabetes, suggesting that the tumor had caused the insulin resistance. This report describes a case of a tumor secreting interleukin-6, which affects both the control of diabetes and CKD progression.

Acute Kidney Injury by Renal Hemosiderosis Secondary to Primary Cold Agglutinin Disease Associated with an Excessive Alcohol Intake.

Renal hemosiderosis occurs in the context of severe intravascular hemolysis, with the most common cause being paroxysmal nocturnal hematuria. Patients with cold agglutinin disease (CAD) have relatively mild hemolysis, and acute kidney injury (AKI) due to renal hemosiderosis has not been reported. We encountered a patient with CAD caused by lymphoplasmacytic lymphoma who developed AKI secondary to renal hemosiderosis after an excessive alcohol intake.

Successful Detection of Renal Involvement in Sjögren's Syndrome Secondary to Systemic Lupus Erythematosus by Renal Biopsy.

An 80-year-old man presented with a mildly decreased renal function and increased anti-double-stranded-DNA (anti-dsDNA) antibody levels, and met the diagnostic criteria of the American College of Rheumatology for systemic lupus erythematosus (SLE). However, the incremental increase in creatinine levels and the mild proteinuria were inconsistent with lupus nephritis. We performed a renal biopsy, which revealed interstitial nephritis and minor glomerular abnormalities. Further examinations determined that the renal lesion was due to Sjögren's syndrome secondary to SLE. Following treatment with oral prednisolone, the patient's renal function improved as his anti-dsDNA antibody levels decreased. This case report indicates that renal biopsy should be considered even in elderly individuals when it may assist in the diagnosis, treatment, and prognosis of the patient.