Yohnosuke Shimomura

Troglitazone Reduces Plasma Leptin Concentration but Increases Hunger in NIDDM Patients

OBJECTIVE Troglitazone, which improves peripheral insulin resistance of experimental diabetic animals and diabetic patients, affects ob gene expression in the adipose tissue of rodents. The present study was undertaken to examine a hypothesis that clinical administration of troglitazone may reduce circulating leptin levels and affect eating behavior in NIDDM patients. RESEARCH DESIGN AND METHODS Troglitazone was administered at a dosage of 200 mg twice daily for 12 weeks in 20 poorly controlled NIDDM patients. Chronological changes in glycemic control, serum lipids, immunoreactive leptin (IRL) levels, and BMI were measured. Body fat weight was also assessed by bioelectric impedance. RESULTS Troglitazone significantly decreased fasting plasma glucose, serum immunoreactive insulin, and HbA1c levels. Serum levels of IRL and triglyceride were significantly reduced by troglitazone administered for 4, 8, and 12 weeks. Troglitazone administration significantly increased the BMI in NIDDM patients, and two-thirds of the patients complained of increased hunger after the start of troglitazone administration. CONCLUSIONS Troglitazone significantly reduces circulating leptin levels at clinical doses. It may affect the eating behavior of poorly controlled NIDDM patients through the improvement of glycemic control and/or the reduction of circulating leptin.

MPO Activity and Generation of Active O2 Species in Leukocytes From Poorly Controlled Diabetic Patients

OBJECTIVE This study was undertaken to determine which part of ROI generation is reduced in the neutrophils from patients with NIDDM. RESEARCH DESIGN AND METHODS Superoxide anion (O2−) production, LDCL activity in response to opsonized zymosan, and MPO activity were measured in leukocytes of poorly controlled NIDDM patients (FBG >8.89 mM, HbA1 >10%). RESULTS In diabetic subjects, both O2− production and LDCL activity assessed with initial slope gradient and peak value were significantly reduced. MPO activity was also decreased in diabetic subjects, and there was a significant correlation between HbA1 levels and MPO activity of diabetic subjects. CONCLUSIONS This study demonstrated that every step in leukocyte ROI generation should be reduced in the leukocytes from poorly controlled diabetic patients.

The significance of decreased ambulatory activity during the generation by long-term observation of obesity in ovariectomized rats.

We attempted to determine the significance of ambulatory activity as a cause of overweight in ovariectomized rats. Drinking and ambulation were measured continuously and directly for periods up to 12 months in special apparatus developed at Gunma University. In older rats, ambulatory activity decreased much more in the ovariectomy group than in the control group. There was no difference in food intake between the ovariectomized and the control group. After 2 months, the ovariectomy group increased body weight more than the control group despite no difference in food intake. The decrease in ambulatory activity was consistent in the ovariectomy group, regardless of any differences in age and body weight. These results indicate that decrease of energy expenditure by gradual decrease in ambulatory activity may be an important factor as a cause of overweight in ovariectomized, obese rats.

Preperitoneal fat deposition estimated by ultrasonography in patients with non-insulin-dependent diabetes mellitus

UNLABELLED Preperitoneal fat is an indicator of visceral fat deposition, which is closely related to atherosclerosis and coronary heart disease in obese patients. We assessed the relationship of preperitoneal fat deposition and various clinical characteristics in 90 patients with non-insulin-dependent diabetes mellitus (NIDDM). Preperitoneal and subcutaneous fat deposition were measured by ultrasonography. In both the male and female diabetics, preperitoneal fat levels were significantly higher than in age-matched healthy subjects. We also determined blood pressures, fasting plasma glucose, glycosylated hemoglobin A1c, serum lipids, fasting immunoreactive insulin (FIRI), daily urinary C-peptide (CPR), serum leptin, urinary albumin excretion and body mass index (BMI). Of these parameters, BMI, FIRI, leptin and daily urinary CPR were positively correlated with preperitoneal fat deposition. Patients with diet therapy alone showed significantly higher preperitoneal fat levels than those receiving insulin therapy. In female, patients with increased preperitoneal fat showed higher prevalence of hypertension than those with decreased fat. Macroalbuminuric patients had a lower preperitoneal fat than microalbuminuric and normoalbuminuric patients. Patients with proliferative retinopathy exhibited lower preperitoneal fat than did those without retinopathy. Preperitoneal fat levels were positively correlated with motor or sensory nerve conduction velocity. CONCLUSION The present findings suggest that in NIDDM patients, increased preperitoneal fat deposition is closely associated with obesity, hypertension and hyperinsulinemia, and negatively modulates diabetic microangiopathy including nephropathy, retinopathy and neuropathy.

Subclinical Hypothyroidism and Indices for Metabolic Syndrome in Japanese Women: One-Year Follow-Up Study

CONTEXT Subclinical hypothyroidism (SCH) and metabolic syndrome (MetS) increase with age; however, their relationship remains unclear. OBJECTIVE Our objective was to investigate the relationship between SCH and indices of metabolic syndrome and follow up subjects for 1 year. DESIGN Cross-sectional and longitudinal follow-up studies of cases were collected from Takasaki Hidaka Hospital between 2003 and 2007. PARTICIPANTS Overall, 11 498 participants of health checkups were analyzed. The mean age was 48 ± 9 years. MAIN OUTCOME MEASURES The relationship between SCH and indices of MetS were examined. RESULTS Serum free T4 levels were lower in women than men in most of the age groups, and the prevalence of SCH, 6.3% in women vs 3.4% in men, increased with age, reaching 14.6% in 70-year-old women. Multivariate logistic-regression analyses revealed that waist circumference and the serum triglyceride and low-density lipoprotein-cholesterol levels were significantly higher in subjects with SCH than without among women. Reflecting these findings, the adjusted odds ratio of MetS in patients with SCH was higher than in the euthyroid subjects in women with an odds ratio of 2.7 (95% confidence interval 1.1-5.6; P = .017) but not in men. Furthermore, progression from euthyroid into SCH resulted in a significant increase in the serum triglyceride levels but not low-density lipoprotein-cholesterol in women. CONCLUSION Japanese women exhibited a high prevalence of SCH associated with low free T4 levels. There was a strong association between SCH and several indices of metabolic syndrome in women. SCH may affect serum triglyceride levels and be a risk factor for metabolic syndrome.

Alpha glucosidase inhibitor voglibose can prevent pioglitazone-induced body weight gain in Type 2 diabetic patients.

Pioglitazone, a member of the thiazolidinedione (TZD) drug family, is widely used for the treatment of Type 2 diabetic patients. This antihyperglycaemic drug is a selective ligand of the nuclear transcription factor, peroxisome proliferator-activated receptor (PPAR) γ. It interacts with PPARγ receptors that are located predominantly in adipose, hepatic and skeletal muscle cells. Modulation of these receptors adjusts the regulation of genes involved in metabolic control and also reduces insulin resistance [1]. However, pioglitazone is known to induce body weight gain [2–4]. Therefore, it is important to control the body weight in usage of PPAR ligands in the treatment of Type 2 diabetes. Alpha glycosidase inhibitors (AGIs) such as voglibose are known to inhibit disaccharide hydrolysis in intestinal mucosa, thereby reducing the hydrolysis of disaccharides to monosaccharides. This impedes absorption of carbohydrate and therefore reduces glucose levels in Type 2 diabetes patients. We have investigated whether it is possible to prevent pioglitazone-induced body weight gain with voglibose treatment. A total of 31 randomly chosen Japanese Type 2 diabetic patients (14 men, 17 women) was recruited into this study. One group was treated for >3 months with diet alone (control group; n = 17, age 60.2 ± 2.5 years, duration of diabetes 11.7 ± 1.5 years); the other was treated with diet plus voglibose (0.9 mg daily) (voglibose group; n = 14, age 61.1 ± 3.6 years, duration of diabetes 9.6 ± 1.3 years). Pioglitazone treatment was given to each group at the dose of 15 mg for 3 months, and dosage was increased to 30 mg for the next 9 months. Diet therapy consisted of 104.6 kJ kg–1 of ideal body weight per day. All patients were instructed to maintain the same energy intake and physical activity as usual for the individual. There was no significant difference in HbA1c levels (8.1 ± 0.3% for control group, 7.9 ± 0.3 for voglibose group) or body mass index (25.9 ± 1.5 for control group, 26.3 ± 1.2 for voglibose group) prior to the trial. Body weight was examined at the beginning and the end of the study. Four patients (one male and three female) dropped out of the trial due to the side-effects of pioglitazone (oedema). There was no significant difference in body weight between the control and voglibose groups before starting the pioglitazone (68.1 ± 5.0 kg for the control group, 72.7 ± 4.7 kg for the voglibose group: the body weight of the voglibose group prior to voglibose treatment was 72.6 ± 4.5 kg). Body weight increased by 0.1 ± 0.3 kg (0.02%) in the voglibose group and 2.5 ± 0.4 kg (3.7%) in the control group (P < 0.01) after pioglitazone treatment (Fig. 1). This result suggests that voglibose treatment prevents the body weight gain induced by pioglitazone. Figure 1 The effect of pioglitazone on body weight change with and without voglibose. *P < 0.01. Students t-test was used for baseline comparison Clinically, it has been shown that TZDs specifically increase subcutaneous adipose tissue [5]. Body weight gain was significantly greater within 4 weeks; it increased on average by 3.88 kg (4.1%) and it did not reach a plateau even after 6 months [5, 6]. In our study, the body weight gain of 3.7% in the pioglitazone monotherapy control group was consistent with these clinical studies. Voglibose is reported to cause side-effects on the small intestine, such as abdominal fullness or diarrhoea for the first several months. These side-effects usually disappear by intestinal adaptation within a couple of months. Since patients require several months to adapt to voglibose, it may be important to start voglibose therapy several months prior to pioglitazone therapy to achieve prevention of body weight gain by pioglitazone. The precise mechanism whereby voglibose may prevent pioglitazone-induced body weight gain is unclear. AGIs have been reported to have no effects on body weight gain or intestinal mass when applied alone [7]. Indeed, in a separate study, we found that monotherapy of voglibose failed to reduce body weight in Type 2 diabetic patients (data not shown). There has been a report that body weight significantly decreased by the combination therapy of acarbose and sulphonylurea compared with sulphonylurea alone [8]. The subjects included in this study did not experience loss of appetite. Therefore, it is likely that the observed effects were independent of the appetite control or intestinal factors. AGIs are known to reduce insulin levels, and it is therefore likely that insulin level of subjects included in this study were reduced [9, 10]. Hyperinsulinaemia can cause body weight gain. We hypothesize that voglibose treatment prior to pioglitazone may have reduced the serum insulin levels, and thus pioglitazone was applied after the reduced insulin levels were established. Therefore, pioglitazone may have improved insulin resistance through this lack of increase in body weight of the patients. To confirm this hypothesis, further investigations are required. In conclusion, we have found that voglibose treatment prevented the increase of body weight induced by pioglitazone in Type 2 diabetes patients. Thus, voglibose may be a potentially useful drug for increasing the benefit of pioglitazone treatment by controlling body weight.

Oral administration of Bifidobacterium longum in a gastro-resistant seamless capsule decreases serum phosphate levels in patients receiving haemodialysis

When kidney function decreases, phosphate (P) per se can initiate and promote hyperparathyroidism and vascular calcification. Therefore, hyperphosphataemia is a widely recognized risk factor for mortality and cardiovascular disease in patients with chronic kidney disease (CKD) [1]. Despite the introduction in the market of new P-binders, such as sevelamer hydrochloride and lanthanum carbonate, the control of hyperphosphataemia in haemodialysis (HD) patients remains difficult because of adverse effects such as constipation and faecal impaction, drug compliance and metal accumulation. We here report an interesting observation that serum P levels can be reduced by modifying the intestinal flora with probiotic administration. This may suggest a new potential approach to better control hyperphosphataemia in HD patients. In patients receiving HD, intestinal aerobic bacteria, such as enterobacteria and enterococci, occur in numbers ∼100 times higher than those in healthy subjects. These aerobes produce putrefactive substances [2]. Oral administration of antibiotic-resistant lactic acid bacteria for 4 weeks can restore the composition of disturbed microflora characterized by overgrowth of aerobes and decreased levels of serum uraemic toxins, including indicant, in HD patients [2]. When administered orally, Bifidobacteria cannot survive exposure to gastric juice before they reach the intestine. In order to enable Bifidobacteria to reach the intestine, a colony-forming unit of Bifidobacterium longum JBL01, a strain of human Bifidobacteria, measuring 2.0 × 109, combined with 0.11 g of oligosaccharides (lactulose and raffinose) as a stimulant to bacteria proliferation, were encapsulated in a gastro-resistant seamless capsule (B capsule, MorishitaJintan Co., Ltd, Osaka, Japan). Bifidobacteria can survive in this gastro-resistant capsule even in a solution of 1.2 pH at 37°C for 120 min. In contrast, Bifidobacteria without the capsule (a powder formulation) cannot be detected immediately after mixing with the solution [3]. Moreover, significant decreases in serum levels of indoxyl sulphate and homocysteine were observed by oral administration of B. longum in the gastro-resistant capsule, but not by the administration of B. longum without the capsule in HD patients [4]. Thus, to improve the composition of disturbed microflora and alleviate faecal impaction, B capsules containing B. longum JBL01 were administered orally once daily for 4 weeks in 15 patients receiving HD [age: 62.2 ± 9.8 years; 10 males, 5 females; 5 diabetes mellitus (DM), 10 non-DM; HD duration: 9.3 ± 7.0 years; serum albumin levels: 3.9 ± 0.3 g/dL; serum corrected calcium (Ca) levels: 9.1 ± 0.8 mg/dL; serum P levels: 6.7 ± 0.6 mg/dL; serum intact parathyroid hormone (PTH) levels: 363 ± 221 pg/mL]. Results were compared with those of 16 HD patients who did not receive B capsules as a control group (age:58.1 ± 15.6 years; 10 males, 6 females; 3 DM, 13 non-DM; HD duration: 9.1 ± 6.8 years; serum albumin levels: 3.8 ± 0.3 g/dL; serum-corrected Ca levels: 9.0 ± 0.9 mg/dL; serum P levels: 7.0 ± 0.8 mg/dL; serum intact PTH levels: 219 ± 124 pg/mL). No patient had undergone treatment with B. longum preparations before participating in this study. The dose of drugs affecting P metabolism were fixed through the study period in the control group (Ca carbonate: 2.79 ± 1.44 g, n= 14; sevelamer hydrochloride: 3.20 ± 2.94 g, n= 5; calcitriol injection: 1.67 ± 0.24 μg/week, n= 3; maxacalcitol: 15.0 ± 4.1 μg/week, n= 3; oral alfacalcidol: 0.5 μg, n= 2, oral calcitriol: 0.38 μg, n= 2) and in the B capsule-treated group (Ca carbonate: 2.50 ± 0.71 g, n= 12; sevelamer hydrochloride: 3.75 ± 0.53 g, n= 4; calcitriol injection: 2.75 μg/week, n= 2; maxacalcitol: 12.5 ± 8.5 μg/week, n= 4; oral alfacalcidol: 0.25 ± 0 μg, n= 3, oral calcitriol: 0.25 μg, n= 1). No patients received lanthanum carbonate or cinacalcet hydrochloride in either group. All data are expressed as mean ± SD or without SD in n= 1 or 2. Oral administration of B capsules for 4 weeks had no significant effect on defecation frequency or faecal hardness determined by the Bristol stool form scale (data not shown). The explanation for this result may be related to the low incidence of obstinate constipation from the beginning in this study (mean defecation frequency: 0.9/day). Serum P levels unexpectedly decreased significantly in the second and fourth weeks due to oral administration of the B capsule (Figure ​(Figure1).1). Serum P levels remained unchanged in the control group. Subsequently, serum P levels returned to original levels 2 weeks after the completion of oral treatment. No significant changes were found in other serum parameters in the B capsule-treated group compared with baseline data and with the control group (data not shown). Fig. 1. Effect of once-daily oral administration of encapsulated B. longum JBL01 with oligosaccharides (B capsule) for 4 weeks on serum P levels in patients on haemodialysis. Open circle: untreated control group (n= 16); filled circle: B capsule-treated group ... The main mechanism for a decrease in serum P levels during B capsule treatment is its ability to lower intestinal pH levels. In the faeces of HD patients, pH levels and ammonia concentrations are elevated due to bacteria-mediated hydrolysis of urea [4]. High levels of ammonia are responsible for elevated pH in faeces and lead to overgrowth of aerobic and putrefactive bacteria. Bifidobacteria can ferment carbohydrates to produce acetic acid and lactic acid, resulting in acidification of the intestinal lumen [4]. Low pH levels in the intestinal milieu inhibit the growth of aerobic and putrefactive bacteria, thus normalizing the intestinal flora. In another study, the administration of B. longum decreased faecal pH levels, and pretreatment levels were restored 1 week after the completion of treatment [5]. Decreased intestinal pH levels due to B capsule treatment may increase the ionization of intestinal Ca. Ca2+ binds with intestinal P ions as an intrinsic P binder. In this study, increased intestinal Ca2+ did not lead to elevated serum Ca levels. Ca2+ may be immediately used in the formation of calcium phosphate in the intestine, and thus not absorbed. Further studies measuring faecal pH, P and Ca excretions will examine this as a possible mechanism in B capsule-treated patients. In this study, although the number of faecal bacteria was not determined during B capsule treatment, the decrease in serum P levels cannot be due to increased uptake of P into the intestinal B. longum for their proliferation. Because feeding of B. longum increases their number, but does not affect the total number of bacteria through a reduction in aerobes in the faeces of healthy subjects [5]. In addition, increased faecal volume and water content are not responsible for low serum P levels, as evidenced by unchanged defecation frequency and faecal hardness among the patients in the present study. It is increasingly recognized that uraemic toxins originating from intestinal microbial metabolism may contribute to the deterioration of renal function, cardiovascular calcification, metabolic bone disease and mortality in CKD/HD patients [6, 7]. The administration of Bifidobacteria can decrease the serum concentrations of indoxyl sulphate and P-cresol in HD patients [4, 7]. In addition, Bifidobacteria produce vitamin B12 and folate, which can normalize serum homocysteine levels in HD patients [3]. This is an important property since most HD patients show hyperhomocysteinaemia, which is a risk factor for cardiovascular disease. Although further investigation is clearly required to clarify the mechanism for the P-reducing effect of the B capsule, Bifidobacteria preparation is a simple and safe treatment for persistent hyperphosphataemia in patients receiving HD. Further studies may identify additional potential benefits of probiotic treatments in CKD/HD patients [6, 7].

Hypertonic glucose impairs glucose-induced increases in cytosol Ca2+ concentration and insulin secretion by HIT-T 15 cells

To evaluate the mechanism of an impaired insulin secretion under diabetic state, we studied the influence of graded degrees of isotonic and hypertonic glucose on the rise in cytosol Ca2+ concentration ([Ca2+]i) and insulin secretion by HIT-T 15 cells. [Ca2+]i was monitored with Fura-2 and insulin secretion was measured with static culture. Both isotonic and hypertonic glucose induced a dose-dependent [Ca2+]i rise and insulin secretion. Although low degrees of isotonic and hypertonic glucose (5 and 15 mM) were equally effective to cause both increases in [Ca2+]i and insulin secretion, high degrees of isotonic glucose (30 and 60 mM) were clearly more effective than the same degrees of hypertonic glucose. The addition of 30 mM sucrose in isotonic 30 mM glucose also decreased the induced increases in [Ca2+]i and insulin secretion, and isotonic sucrose was ineffective in inducing either an increase in [Ca2+]i or insulin secretion. Removal of medium Ca2+ inhibited the 30 mM isotonic glucose-induced [Ca2+]i rise and insulin secretion. These data suggest that an impaired rise in [Ca2+]i, which was caused by blocking of Ca2+ influx due to hyperosmolarity, may be one mechanism by which glucose can not stimulate appropriate insulin secretion under diabetic state.

Non-alcoholic Fatty Liver Disease Is a Risk Factor for Type 2 Diabetes in Middle-aged Japanese Men and Women

Objective Emerging studies have focused on the association between non-alcoholic fatty liver disease (NAFLD) and the risk of type 2 diabetes mellitus (T2DM). We aimed to investigate whether NAFLD diagnosed by ultrasonography could predict the risk of future T2DM in a Japanese middle-aged health check population. Methods We conducted a 10-year observational study in a health checkup population of middle-aged Japanese men and women at Hidaka Hospital from 2004 to 2013. We excluded cases with an alcohol intake exceeding 20 g/day and those with impaired glucose tolerance. The remaining 1,544 men and 864 women were classified into fatty liver and non-fatty liver groups based on the findings of abdominal ultrasonography. Both groups were followed for the development of diabetes. A multiple regression analysis was performed for each variable to predict the risk of future diabetes. Results The median age of the participants was 46.0 years at the entry, and the follow-up period was 10 years. The incidence of diabetes in the fatty liver group was 12.5% (29/232) in men and 26.3% (10/38) in women, whereas the incidence of diabetes in the non-fatty liver group was 2.5% (34/1,312) in men and 1.8% (15/826) in women. The relative risk of diabetes associated with fatty liver was 4.8 [95% confidence interval (CI) 3.0 -7.8, p<0.0001] in men and 14.5 (95% CI 7.0-30.1, p<0.0001) in women. Conclusion NAFLD was a significant predictor for future diabetes in a Japanese middle-aged health check population, especially in women.

ENTERAL HYPERALIMENTATION WITH CONTINUOUS SUBCUTANEOUS INSULIN INFUSION IMPROVED SEVERE DIARRHEA IN POORLY CONTROLLED DIABETIC PATIENT

Little is known about effective treatment for severe diarrhea in the insulin-dependent diabetic patient. A 41-year-old woman was admitted to our hospital because of hyperglycemia and dysuria. She had stopped insulin self-injection therapy for 2 years and diarrhea had become worse, resulting in malnutrition. Following enteral alimentation by elemental diet (ED) with continuous subcutaneous insulin infusion (CSII), frequency of diarrhea remarkably decreased and general nutritional condition was improved. At the first step, the patient was given 600 kcal/d ED through the tube sustained in the jejunum. Total calorie intake for 24 hours was gradually increased to the level of 2400 kcal/d and this therapy continued for 5 months. During this period, blood glucose level was kept in almost normal range (between 100 and 200 mg/dL) through the continuous insulin infusion of regular insulin (1.0-1.5 U/h). Thereafter, general conditions were improved and frequency of diarrhea gradually decreased. When this treatment was stopped, watery diarrhea, steatorrhea, and hypoalbuminemia completely disappeared and she gained 12 kg of body weight. Furthermore, spontaneous urination appeared following this treatment. This case suggests that the enteral hyperalimentation combined with strict control of blood glucose, using the CSII, may be an effective therapy for such severe diarrhea with malnutrition in diabetes.