Specific Expression of KCC2 in the α Cells of Normal and Type 1 Diabetes Model Mouse Pancreatic Islets.

Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in the mature brain; however, it acts excitatory during development. This difference in action depends on the intracellular chloride ion concentration, primarily regulated by potassium chloride co-transporter2 (KCC2). Sufficient KCC2 expression results in its inhibitory action. GABA is also abundant in pancreatic islets, where it acts differentially on the islet cells, and is involved in carbohydrate metabolism. However, the mechanisms underlying the differential action remain unknown. We performed immunohistochemistry for glutamic acid decarboxylase (GAD), a synthetic enzyme for GABA, and KCC2 in normal adult islets. GAD was co-localized with insulin in ß cells, whereas KCC2 was expressed in glucagon-positive α cells. These results are in line with previous observations that GABA decreases glucagon release but increases insulin release, and suggest that GABA and insulin may work together in reducing blood glucose levels under hyperglycemia. Next, we examined the streptozotocin-induced type1 diabetes mellitus mouse model. GAD and insulin expression levels were markedly decreased. KCC2 was expressed in glucagon-positive cells, whereas insulin- and somatostatin-positive cells were KCC2-negative. These findings suggest that in diabetes model, reduced GABA release may cause disinhibition of glucagon release, resulting in increased blood sugar levels and the maintenance of hyperglycemic state.

Association of Erythropoietin Resistance with Fatigue in Hemodialysis Patients: A Cross-Sectional Study.

BACKGROUND/AIMS: Fatigue is a common symptom in patients receiving hemodialysis (HD) and is generally associated with anemia. However, it can be difficult to resolve, even when anemia has been treated using erythropoiesis-stimulating agents and iron replacement therapy. In the present study, we examined the associations of anemia, the erythropoietin resistance index (ERI) and iron deficiency with fatigue during HD. METHODS: In this cross-sectional study, fatigue score was calculated on the basis of questionnaire responses in HD patients. Participants were divided into 3 groups according to their hemoglobin (Hb) levels (low, normal and high). Iron deficiency was assessed as a transferrin saturation (TSAT) of <20%. RESULTS: We included 571 HD patients (men/women 368/203; mean age 62.2 ± 10.8 years). Among the 3 groups, fatigue scores increased significantly with decreasing Hb levels. HD patients with low Hb levels (<90 g/l) had significantly higher fatigue scores than those with higher Hb levels (≥120 g/l). In the multiple regression analysis, we showed that a high ERI (ß = 0.208) and a low TSAT (ß = -0.155), but not the Hb level, were significantly associated with increased fatigue score. Moreover, this was independent of age, gender and modifiable confounders linked to anemia. Even after restricting patients to those without iron deficiency (TSAT ≥20%), the ERI (ß = 0.258) retained a significant and independent association with the fatigue score. CONCLUSION: Iron deficiency and a high ERI despite iron sufficiency may cause fatigue in HD patients.

Successful treatment with ustekinumab of psoriasis vulgaris in a patient undergoing hemodialysis.

Psoriasis is a common chronic inflammatory skin disease but psoriasis patients with renal impairment undergoing dialysis are not frequently seen. Furthermore, the published work contains little information on the treatment with biologic drugs of patients with end-stage renal disease. We describe a 57-year-old man with refractory plaque-type psoriasis and end-stage renal disease due to polycystic kidney disease undergoing hemodialysis. He had tried topical medications and ultraviolet therapy for many years and was then treated with ustekinumab (an interleukin-12 and interleukin-23 blocker), which resulted in good clinical response along with stable renal function. After a few years of therapy, no side-effects have been observed. Our experience with this patient expands the spectrum of ustekinumab to include psoriasis patients with renal failure undergoing hemodialysis.

Effects of nutritional supplementation on fatigue, and autonomic and immune dysfunction in patients with end-stage renal disease: a randomized, double-blind, placebo-controlled, multicenter trial.

BACKGROUND: Fatigue is a predictor of cardiovascular events in patients with end-stage renal disease (ESRD) undergoing hemodialysis treatment. We hypothesized that multinutritional support would improve quality of life, fatigue symptoms, and potential quantitative measures including endocrine, immune and autonomic functions in patients with ESRD undergoing hemodialysis. METHODS: Two hundred and two hemodialysis patients were randomly assigned to receive active treatment (containing vitamin B1, vitamin B2, niacin, vitamin B6, vitamin B12, folic acid, vitamin C, carnitine, coenzyme Q10, naïve galacto-oligosaccharide, and zinc) or placebo after each dialysis session for 12 weeks. The patients and attending physicians were blinded to the treatment, and 172 patients (86 in each group) completed the study. Fatigue was evaluated via fatigue questionnaire at 0, 4, and 12 weeks. To assess human herpes virus (HHV) 6 and 7 reactivation, numbers of viral DNA copies were determined in saliva by polymerase chain reaction at weeks 0 and 12. Autonomic function was determined via measurement of beat-to-beat variation by using acceleration plethysmography. RESULTS: Clinical characteristics, changes in fatigue, quality of life score, endocrine functions, and laboratory data did not differ significantly between the two groups. Several parameters of heart rate variability significantly increased after nutritional treatment compared to placebo. Nutritional drink for 12 weeks significantly suppressed HHV7 DNA copy numbers. Similarly, HHV6 DNA copy numbers tended to be decreased by treatment but without reaching statistical significance. CONCLUSIONS: Nutritional supplementation may modulate immune and autonomic dysfunction in ESRD patients undergoing hemodialysis.

Effects of raloxifene on bone metabolism in postmenopausal women on chronic hemodialysis.

BACKGROUND: Postmenopausal women with end-stage renal failure are at an increased risk of fracture because of the effects of secondary hyperparathyroidism and postmenopausal osteoporosis. In the present study, we investigated the feasibility of using raloxifene to prevent fractures in postmenopausal women with end-stage renal failure on hemodialysis. METHODS: This study was conducted using a multicenter, single-arm, prospective design. Raloxifene was administered to postmenopausal women aged ≥50 years who were on maintenance hemodialysis and met any of the following criteria after a 24-week run-in period: an alkaline phosphatase level (bone formation marker) of ≥6.18 µkat/L (≥370 U/L), a bone-specific alkaline phosphatase (BAP; bone formation marker) level of ≥0.59 µkat/L (≥35.4 U/L), or a bone-derived tartrate-resistant acid phosphatase (TRACP-5b; bone resorption marker) level of ≥4.2 U/L. RESULTS: A total of 48 individuals were eligible for study inclusion. Of them, 30 individuals participated in this study. The BAP levels were significantly decreased at week 4, but returned to the baseline levels at week 24. Similarly, the TRACP-5b levels were significantly decreased at week 4, but returned to the baseline levels at week 24. The serum calcium value decreased consistently after the start of raloxifene therapy. The intact parathyroid hormone (iPTH) levels were likely increased at week 4. The ratio of BAP to iPTH levels and the ratio of TRACP-5b to iPTH levels both showed significant decreases over time. During the raloxifene therapy, no thrombosis or other drug-related adverse events developed. CONCLUSION: The study results indicated that raloxifene can transiently reduce the levels of bone metabolism markers and might be useful for preventing fractures in postmenopausal women with end-stage renal failure, although raloxifene use over the long term may not have adequate efficacy in the absence of appropriate concomitant active vitamin D therapy.

Fatigue is a predictor for cardiovascular outcomes in patients undergoing hemodialysis.

BACKGROUND AND OBJECTIVES: Despite potential significance of fatigue and its underlying components in the occurrence of cardiovascular diseases, epidemiologic data showing the link are virtually limited. This study was designed to examine whether fatigue symptoms or fatigue's underlying components are a predictor for cardiovascular diseases in high-risk subjects with ESRD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: 788 volunteer patients under hemodialysis therapy (506 male, 282 female) completed the survey between October and November 2005, with the follow-up period up to 26 months to monitor occurrence of fatal or nonfatal cardiovascular events. The questionnaire consisted of 64 questions, and promax rotation analysis of the principal component method conceptualized eight fatigue-related factors: fatigue itself, anxiety and depression, loss of attention and memory, pain, overwork, autonomic imbalance, sleep problems, and infection. RESULTS: 14.7% of the patients showed fatigue scores higher than twice the SD of the mean for healthy volunteers. These highly fatigued patients exhibited a significantly higher risk for cardiovascular events (hazard ratio: 2.17; P < 0.01), with the relationship independent of the well-known risk factors, including age, diabetes, cardiovascular disease history, and inflammation and malnutrition markers. Moreover, comparisons of the risk in key subgroups showed that the risk of high fatigue score for cardiovascular events was more prominent in well-nourished patients, including lower age, absence of past cardiovascular diseases, higher serum albumin, and high non-HDL cholesterol. CONCLUSIONS: Fatigue can be an important predictor for cardiovascular events in patients with ESRD, with the relationship independent of the nutritional or inflammatory status.

Association of glycated albumin, but not glycated hemoglobin, with calcaneus quantitative ultrasound in male hemodialysis patients with type 2 diabetes mellitus.

Sustained high glucose impairs bone metabolism in patients with type 2 diabetes mellitus (T2DM). In this study, the relationship between glycemic control and bone metabolism was examined in male hemodialysis (HD) patients with T2DM. To avoid the effect of menstruation and the menstrual cycle, obesity, and glycosuria-induced hypercalciuria on bone metabolism, male anuric nonobese HD patients with T2DM (n = 42) were enrolled. Calcaneus stiffness index (SI) was determined using ultrasound after HD session. Casual plasma glucose (PG), glycated hemoglobin (HbA(1c)), and glycated albumin (GA) were measured before the HD session. In simple regression analysis, log PG (r = -0.333, P < .05) and log GA (r = -0.350, P < .05), but not log HbA(1c) (r = -0.134, P = .3985), exhibited significant and negative correlations with calcaneus SI. In multiple regression analysis including log BMI, log cCa x Pi product, and log PG, log PG was associated significantly in a negative manner with calcaneus SI, in addition to log cCa x Pi product. When log PG was replaced with log GA or log HbA(1c), log GA, but not log HbA(1c), emerged as a significant factor associated. The mechanism as to why HbA(1c) failed to associate could be explained by its false reduction by erythropoietin injection. The present study supported the notion of GA as an appropriate indicator for glycemic control in HD patients with T2DM. Furthermore, it is suggested that poor glycemic control might be a significant factor toward decreasing calcaneus SI in T2DM HD patients.

Association of glycated albumin, but not glycated hemoglobin, with peripheral vascular calcification in hemodialysis patients with type 2 diabetes.

AIMS: Elevated HbA(1C) is a predictor of mortality as well as peripheral vascular calcification in hemodialysis (HD) patients with diabetes. However, improved glycemic control as reflected by reduction in HbA(1C) may dismiss the relationship between HbA(1C) and mortality in those patients, due possibly to the underestimation of HbA(1C) by erythropoietin use. This study was to establish the significance of glycated albumin (GA) as a useful marker of peripheral vascular calcification in diabetic HD patients, in comparison with HbA(1C). MAIN METHODS: We examined 49 HD patients with type 2 diabetes (37 men and 12 women). Peripheral vascular calcification at hand arteries was checked on a simple X-ray photograph. GA and HbA(1C) were determined just before HD session. KEY FINDINGS: The prevalence of peripheral vascular calcification was significantly higher in diabetic patients (65.3%) than in non-diabetic patients (27.0%). Multiple regression analyses in diabetic patients showed that both HD duration and GA were significantly associated with the presence of peripheral vascular calcification. When GA was replaced by HbA(1C) in the same model, HbA(1C) failed to show a significant association. However, when a weekly dose of erythropoietin was simultaneously included in addition to HD duration and HbA(1C), both HbA(1C) as well as HD duration emerged as a significant factor associated with the presence of peripheral vascular calcification. SIGNIFICANCE: The present study suggested that GA might be a better indicator of glycemic control, and raise the possibility that improvement of glycemic control might prevent against the development of peripheral vascular calcification in diabetic HD patients.

Glycated albumin is a better glycemic indicator than glycated hemoglobin values in hemodialysis patients with diabetes: effect of anemia and erythropoietin injection.

The significance of glycated albumin (GA), compared with casual plasma glucose (PG) and glycated hemoglobin (HbA(1c)), was evaluated as an indicator of the glycemic control state in hemodialysis (HD) patients with diabetes. The mean PG, GA, and HbA(1c) levels were 164.5 +/- 55.7 mg/dl, 22.5 +/- 7.5%, and 5.85 +/- 1.26%, respectively, in HD patients with diabetes (n = 538), which were increased by 51.5, 31.6, and 17.7%, respectively, compared with HD patients without diabetes (n = 828). HbA(1c) levels were significantly lower than simultaneous PG and GA values in those patients in comparison with the relationship among the three parameters in patients who had diabetes without renal dysfunction (n = 365), as reflected by the significantly more shallow slope of regression line between HbA(1c) and PG or GA. A significant negative correlation was found between GA and serum albumin (r = -0.131, P = 0.002) in HD patients with diabetes, whereas HbA(1c) correlated positively and negatively with hemoglobin (r = 0.090, P = 0.036) and weekly dose of erythropoietin injection (r = -0.159, P < 0.001), respectively. Although PG and GA did not differ significantly between HD patients with diabetes and with and without erythropoietin injection, HbA(1c) levels were significantly higher in patients without erythropoietin. Categorization of glycemic control into arbitrary quartile by HbA(1c) level led to better glycemic control in a significantly higher proportions of HD patients with diabetes than those assessed by GA. Multiple regression analysis demonstrated that the weekly dose of erythropoietin, in addition to PG, emerged as an independent factor associated with HbA(1c) in HD patients with diabetes, although PG but not albumin was an independent factor associated with GA. In summary, it is suggested that GA provides a significantly better measure to estimate glycemic control in HD patients with diabetes and that the assessment of glycemic control by HbA(1c) in these patients might lead to underestimation likely as a result of the increasing proportion of young erythrocyte by the use of erythropoietin.