Highlights • The difference in the dipeptidyl peptidase-4 activity exists in-between persons with type 1, type 2 and latent autoimmune diabetes in adults. • Dipeptidyl peptidase-4 activity is highest ...in persons with latent autoimmune diabetes in adults. • Dipeptidyl peptidase-4 activity correlates with glutamic acid autoantibody. • Dipeptidyl peptidase-4 inhibitors might be considered in treatment of autoimmune diabetes.
To compare the antihyperglycemic effects of metformin and creatine in recently detected type II diabetics in a short-term clinical study.
In a 14 day simmetrically randomized crossover study, ...recently detected type II diabetics received either creatine (2x3 g/day) or metformin (2x500 mg/day) for five days, followed by two days of washout, followed by cross-over to the opposite treatment for the next five days. Fasting and post-prandial (-15, 60, 90, 120, 180 and 240 min) blood glucose, insulin, c-peptide, creatine and lactate were measured every other day for the duration of treatment, and HbA1c only at the begining and at the end of the study.
Both creatine and metformin decreased glucose concentrations to similar levels at all time points vs. basal glucose values -15, 60, 90, 120, 180, and 240 min: 11.1+/-0.75 vs 9.1+/-0.55a vs 8.8+/-0.59b, 14.4+/-0.6 vs 12.9+/-0.47a vs 13.1+/-0.55a, 14.8+/-0.58 vs 13.0+/-0.46b vs 13.3+/-0.55a, 14.1+/-0.6 vs 11.9+/-0.42b vs 12.5+/-0.51a, 12.2+/-0.6 vs 9.6+/-0.36c vs 9.9+/-0.38c, and 10.1+/-0.47 vs 7.8+/-0.36c vs 8.4+/-0.4b; (aP < 0.05; bP < 0.01; cP < 0.001 vs. basal glucose values). Neither treatment altered insulin, c-peptide, or HbA1c. Lactate varied during the day, but never reached the upper level of the safety reference range.
Short-term treatment with creatine and metformin elicits similar glucose lowering effects in recently detected type II diabetics. Further studies are necessary to determine the effect of creatine on long-term glucose and insulin regulation.
We report on the stimulatory effect of creatine on insulin secretion and ATP concentration in MIN-6 beta-cells. The addition of creatine (5 mM) to MIN-6 cells in the presence of glucose (1-10 mM) ...elicited a significant (p<0.001) increase in insulin secretion, but no effect was demonstrated in the absence of glucose. The lack of effect of creatine in the absence of glucose suggests that creatine may act as a potentiator of insulin secretion rather than as an initiator. The potentiatory effect of creatine is specific for glucose since no effect was found in the presence of other known initiators of insulin secretion (K(+), 2-ketoisocaproic acid and tolbutamide). Cellular ATP content was markedly increased by glucose (1-15 mM). Creatine (5 and 10 mM) further increased the ATP level at all glucose concentrations, and the effect was observed even in the absence of glucose. The results from this study demonstrate the ability of creatine to increase insulin secretion only in the presence of glucose, while its effect on increased cellular ATP was independent of the presence of glucose. The mechanism whereby creatine potentiates insulin release is yet to be investigated. However, our data suggest possible unique interactions between creatine and the glucose-dependent insulin secretory pathway.
A total of 1419 children with type 1 diabetes mellitus was investigated in order to assess the true frequency of Hashimoto's thyroiditis (HT), diagnosed by microsomal and/or thyroglobulin ...autoantibodies, by ultrasound and in many cases also by fine needle biopsy. According to these criteria, 55 cases (3.9%) of HT were identified, a number significantly higher (P < 0.0001) than the distribution reported in the normal paediatric population. No typical antibody pattern was seen prior to the onset of HT, nor was an antibody threshold level found which could have been diagnostic for this disease. Patients with subclinical hypothyroidism were treated with L-thyroxine and were investigated regarding the behaviour of anti-thyroid autoantibodies; however, no significant changes were seen. The data showed a high frequency of HT in diabetic children, and therefore we recommend that children with type 1 diabetes mellitus should be screened for thyroid autoantibodies and those positive should undergo periodic thyroid function testing.
The scheme shows the binding of uric acid (
1a) to the critical Arg residue; its equivalent
2a (R
=
H) did not affect insulin release.
Uric acid (
1a) suppresses basal insulin release in isolated rat ...pancreatic islets and inhibition of glucose-stimulated insulin secretion (GSIS) occurs right at hyperuricaemic levels (⩾0.4
mM). Conversely, 1
mM guanidinium urate (
2a) was completely ineffective, strongly suggesting that binding to an essential arginine residue triggers the inhibitory effect. A specific recognition of
1a molecule at the crucial β-cell receptor is probably involved in the blocking glucose signal transduction.
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