Hana Kozai

Serum brain-derived neurotrophic factor in patients with type 2 diabetes mellitus: Relationship to glucose metabolism and biomarkers of insulin resistance

OBJECTIVES The aims of this study were to measure serum levels of brain-derived neurotrophic factor (BDNF) in patients with type 2 diabetes mellitus (T2DM) and to investigate the association of these BDNF levels with biomarkers of glucose metabolism and insulin resistance. DESIGN AND METHODS We studied 112 patients with T2DM and 80 age- and gender-matched control subjects. RESULTS Serum BDNF levels were significantly lower in patients with T2DM compared to control subjects (15.5+/-5.2 ng/mL vs. 20.0+/-7.3 ng/mL, P<0.01). In patients with T2DM, BDNF levels were significantly higher in females than in males (P<0.01). In the female patients, BDNF was positively related to immunoreactive insulin (IRI) (rho=0.458, P<0.05) and HOMA-R (rho=0.444, P<0.05). Stepwise multiple regression analysis showed a significant relationship between BDNF and IRI (F=5.294, P<0.05) in female patients with diabetes. CONCLUSIONS These findings suggest that BDNF may contribute to glucose metabolism.

Intervention with Delivery of Diabetic Meals Improves Glycemic Control in Patients with Type 2 Diabetes Mellitus

The aim of this study was to investigate the effects of a diabetic meal delivery system on glycemic control over a 12 month period in patients with type 2 diabetes. A total of 77 patients with type 2 diabetes were assigned randomly into three dietary intervention groups: group M, diabetic meal delivery; group D, individual dietary counseling; and group C, conventional dietary education. In group M, HbA1c levels decreased significantly from 8.2 ± 1.2% to 7.4 ± 0.8% after 12 months (p<0.05), while in group D, HbA1c levels decreased significantly throughout the entire 12 month period, from 8.5 ± 1.7% at baseline to 7.4 ± 1.1% at the endpoint. Similarly, fasting blood glucose (FBG) levels decreased significantly between 1 and 12 months in group M (p<0.05), and decreased significantly during the entire 12 month period in group D (p<0.01). There were no significant changes in either HbA1c or FBG levels in group C. This study provides evidence that intervention with delivery of diabetic meals to patients with type 2 diabetes can be equally effective for achieving glycemic control as individual dietary counselling by a dietitian. Diabetic meal delivery can therefore be used successfully to provide diabetes education to outpatients.

The α-glucosidase inhibitor acarbose reduces the net electronegative charge of low-density lipoprotein in patients with newly diagnosed type 2 diabetes

BACKGROUND Several epidemiological studies have shown that postprandial hyperglycemia is associated with an increased risk of cardiovascular disease (CVD). The present study was conducted in order to compare the effects of acarbose and glimepiride treatment on serum lipoprotein profiles in patients with type 2 diabetes. METHODS A total of 37 patients with newly diagnosed type 2 diabetes were studied. The patients were assigned randomly to treatment for 12 weeks with either acarbose (n=13, 100 mg x 3/day, group A), glimepiride (n=13, 2 mg/day, group G) or diet only (n=11, group D). Lipid and lipoprotein profiles before and after each treatment were evaluated. RESULTS A significant reduction in the net electronegative charge of low-density lipoprotein (emLDL) was observed in group A (-1.8, P<0.01), whereas no significant change in emLDL was observed in groups G and D. In group A, small VLDL and very small LDL levels were also decreased significantly (P<0.05). The change in emLDL levels correlated significantly with changes in very small LDL (r=0.751, P<0.01) and oxidized LDL levels (r=0.623, P<0.05). CONCLUSION These results suggest that measurement of serum emLDL may be a sensitive and clinically useful marker for determining qualitative lipoprotein abnormalities in diabetes, and that acarbose treatment lowers CVD risk by decreasing production of emLDL.

Randomized Controlled Trial of Two Forms of Self-Management Group Education in Japanese People with Impaired Glucose Tolerance

The aim of this study was to determine the effectiveness of education on diabetes prevention in subjects with impaired glucose tolerance. A total of 100 subjects of impaired glucose tolerance with hemoglobin A1c (HbA1c) levels ≥5.5 to <6.1% were assigned randomly to either support or control groups. All subjects received education in 8 sessions over a 6-month period. The support group consisted of 10 members collaborating with a dietitian or a nurse who learned coping skills by employing a participant-centered approach. Participants in the support group were required to keep a diary that monitored weight, food intake and blood glucose levels, while the control group attended several lectures. Subjects assigned to the support group had a reduction in mean HbA1c levels from 5.77 ± 0.36% at baseline to 5.39 ± 0.24% at the endpoint (p<0.01). Weight, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels also decreased (p<0.01) in the support group, whereas subjects in the control group had no observable reduction in these indices. After intervention, participants of the support group had improvements in their 2-h post-meal blood glucose levels. Support group education can be effective for improving glycemic control in participants when carried out in collaboration with educators and other team members.

Anti-allergic effects of His-Ala-Gln tripeptide in vitro and in vivo.

We examined the inhibitory effects of HAQ (His-Ala-Gln) peptide on type-1 allergy in vitro and in vivo. HAQ peptide inhibited β-hexosaminidase release and intracellular Ca2+ levels of rat basophilic leukemia RBL-2H3 cells. Oral administration of a HAQ peptide-added diet (1 mg/mouse/administration) to C3H/HeJ mice for 14 days led to significant suppression of allergic symptoms, but did not reduce allergen-specific IgE or IgG1.