Development of Pretreatment Protocols for Determination of Soybean β-Conglycinin in Processed Soybean Foods Using Commercial ELISA Kits

β-Conglycinin is the major storage protein in soybeans. Pre-clinical animal models and human clinical studies have demonstrated the triglyceride-lowering effect of this protein, suggesting that it could be put into practical use as a functional food material. To date, however, there are no accurate and simple assays for quantification of β-conglycinin. In this study, samples were pretreated by mixing them with rice flour powder prior to extraction of proteins. Then, we used commercially available ELISA kits for detection of allergens that could be present in any contaminating soybean residue. This enabled accurate and highly reproducible quantitation of β-conglycinin content in several processed soybean foods.

Oral Administration of Okara Soybean By-Product Attenuates Cognitive Impairment in a Mouse Model of Accelerated Aging

The microbiota-gut-brain axis has attracted increasing attention in the last decade. Here, we investigated whether okara, a soybean by-product rich in dietary fiber, can attenuate cognitive impairment in senescence-accelerated mouse prone 8 (SAMP8) mice by altering gut microbial composition. Mice were fed either a standard diet, or a diet containing okara (7.5% or 15%, w/w) for 26 weeks. In the memory test, the 7.5% okara-fed mice showed a longer step-through latency and the 15% okara-fed mice had a short escape latency compared with control mice. The 15% okara-fed mice displayed decreased body weight, increased fecal weight, and altered cecal microbiota composition compared with the control group; however, there was no significant difference in the serum lactic acid and butyric acid levels among these mice groups. The 7.5% okara-fed mice had significantly higher NeuN intensity in the hippocampus compared with control mice. Furthermore, a decrease in inflammatory cytokine TNF- and an increase in brain-derived neurotrophic factor (BDNF) was observed in the 7.5% okara-fed group. The expression of synthesizing enzyme of acetylcholine was increased by the okara diets, and the acetylcholine level in the brain was higher in the 7.5% okara-fed group than in the control. These suggest that oral administration of okara could delay cognitive decline without drastically changing gut microbiota.

Association between urinary angiotensinogen levels and renal and cardiovascular prognoses in patients with type 2 diabetes mellitus

Aims/Introduction:  Activation of the renin‐angiotensin system (RAS) in the kidney plays an important role in renal function. The aim of this study was to investigate whether plasma and urinary angiotensinogen levels were associated with renal and cardiovascular prognosis in type 2 diabetic patients.

Materials and Methods:  We measured plasma and urinary angiotensinogen levels in the observational follow‐up cohort of 234 Japanese type 2 diabetic patients (144 with normoalbuminuria, 90 with albuminuria) enrolled between 1998 and 1999 and followed them up until the end of 2008. The associations of these markers with the annual decline in the estimated glomerular filtration rate (eGFR) and incidence of renal and cardiovascular composite endpoints (chronic hemodialysis, myocardial infarction, angina pectoris, stroke and cerebral hemorrhage) were evaluated.

Results:  At baseline, urinary angiotensinogen levels correlated with urinary albumin‐creatinine ratio, urinary β₂‐microglobulin and inversely with eGFR. In contrast, plasma angiotensinogen levels correlated neither with these renal factors nor with urinary angiotensinogen levels. In the follow‐up study (median duration: 9 years), urinary angiotensinogen, but not plasma angiotensinogen, correlated inversely with the annual change in eGFR (r = −0.51, P < 0.001). When patients were divided into four subgroups according to albuminuria and urinary angiotensinogen levels, patients with albuminuria and high urinary angiotensinogen levels showed a progressive decline of eGFR and a higher incidence of renal and cardiovascular composite endpoints.

Conclusions:  These results suggest that the higher level of urinary angiotensinogen in type 2 diabetic patients with albuminuria is a high risk factor for worsening renal and cardiovascular complications. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00172.x, 2011)

Impact of renin-angiotensin system inhibition on microalbuminuria in type 2 diabetes: a post hoc analysis of the Shiga Microalbuminuria Reduction Trial (SMART)

The Shiga Microalbuminuria Reduction Trial (SMART) showed the advantage of ARB over CCB beyond the blood pressure (BP)-lowering effect in reducing microalbuminuria. To further assess the impact of BP control or renin-angiotensin system inhibition on microalbuminuria, the SMART patients were re-analyzed. Hypertensive patients with type 2 diabetes and microalbuminuria were randomly assigned to valsartan or amlodipine treatment groups for 24 weeks. Target blood pressure was set at <130/80 mmHg. Changes in the urinary albumin creatinine ratio (ACR) from baseline were assessed in the valsartan monotherapy (VM) group (n=33), the amlodipine monotherapy (AM) group (n=36), the concomitant valsartan and angiotensin-converting enzyme inhibitor group (VA) (n=33), and the concomitant amlodipine and angiotensin-converting enzyme inhibitor (AA) group (n=38). At the end of the study, mean BP was not different among the four treatment groups. The changes in ACR from baseline to the end of the treatment period in VM, AM, VA, and AA were -36%, +30%, -26%, and +8%, respectively. The dissociation between the anti-albuminuric and antihypertensive effects of valsartan or amlodipine was observed in the respective monotherapy groups. In the AA group, however, a significant positive relationship was found between the changes in ACR and those in systolic BP. In conclusion, RAS inhibitors may be necessary in order for calcium channel blockers to have an effect on microalbuminuria. Therefore, RAS inhibitors are first-line drugs for hypertensive patients with type 2 diabetes and microalbuminuria.

Renal handling of urate in a patient with familial juvenile gouty nephropathy

We encountered a case of familial juvenile gouty nephropathy (FJGN) with an autosomal dominant transmission pattern. Hyperuricemia in the propositus was caused by renal underexcretion of urate although his erythrocyte purine enzyme was normal. A renal biopsy specimen from the propositus showed interstitial fibrosis with tubular atrophy. On pyrazinamide and probenecid tests, the tubular secretion of urate selectively decreased without changes in either presecretory or postsecretory reabsorption of urate when his renal function was normal. Probenecid increased the urinary urate excretion and Cur/Ccr. The serum urate concentration was poorly controlled by allopurinol. When his renal function deteriorated, the uricosuric effects of both probenecid and benzbromarone were attenuated. However, the combined administration of probenecid with allopurinol decreased the serum urate concentration. These data suggest that the tubular secretion of urate is selectively impaired in FJGN and at the stage of renal failure, the combination of an uricosuric agent with allopurinol might be effective in treating hyperuricemia in FJGN.

Blocking effect of 1389-S on the sodium current in isolated guinea-pig ventricular myocytes

Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation.