Diabetes research (Scotland) 

About: Diabetes research (Scotland) is an academic journal. The journal publishes majorly in the area(s): Diabetes mellitus & Insulin. Over the lifetime, 713 publications have been published receiving 9556 citations.

Islet amyloid, increased A-cells, reduced B-cells and exocrine fibrosis: quantitative changes in the pancreas in type 2 diabetes.

Abstract: Morphometric analysis of the endocrine and exocrine pancreas was done on immunoperoxidase stained post-mortem tissue from 15 Type 2 diabetic and 10 age-matched control subjects. Thirteen of the 15 Type 2 diabetic patients had islet amyloid deposits (mean, 6.5% islet area) in the corpus (body, tail and anterior part of the head) but not in the caput (the "pancreatic polypeptide rich" part of the head) whereas none was seen in control subjects. In the corpus in diabetic subjects, the pancreatic area density of B-cells was decreased by 24% (p = 0.005) and A-cells increased by 58% (p less than 0.001) compared with control subjects. The mean A/B-cell ratio increased in the corpus from 0.27 in control subjects to 0.57 in Type 2 diabetic patients. Positive immunoreactivity for the amyloid constituent peptide, Diabetes Associated Peptide, was demonstrated in islet amyloid of diabetic subjects and in B-cells of control and diabetic subjects. The increase in A-cells may contribute to the hyperglucagonaemia and hyperglycaemia of Type 2 diabetes. The impaired insulin secretion in Type 2 diabetes may be due to a decrease in B-cells and to disruption of the islet structure by amyloid. Exocrine fat was similar in the control and diabetic subjects with both groups having more in the corpus than the caput. Diabetic subjects had increased exocrine fibrosis in the corpus region (p less than 0.001), but not in the caput. Exocrine fibrosis may be secondary to disordered islet cell function.

Dietary supplementation of omega-3 polyunsaturated fatty acids improves insulin sensitivity in non-insulin-dependent diabetes.

Abstract: The effect of dietary omega-3 polyunsaturated fatty acids on the lipid composition and fluidity of erythrocyte membranes, and on in vivo insulin sensitivity was studied in 6 non-insulin-dependent diabetic (NIDD) patients. An 8 weeks daily supplementation of 3 g of the omega 3 fatty acids eicosapentaenoic and docosahexaenoic acid resulted in an increase of the membrane phospholipid unsaturation and the sphingomyelin content. Erythrocyte membrane fluidity, measured with electron spin resonance of intact erythrocytes and with fluorescence polarization of erythrocyte ghosts, did not change. The in vivo insulin stimulated glucose uptake was estimated by determining the metabolic clearance rate (MCR) of glucose in the steady state of a simultaneous infusion during 150 min of glucose (33 mumol/kg/min) and insulin (50 mU/kg/hr). The MCR of glucose increased in all patients; from 3.93 +/- 0.55 - 4.69 +/- 0.74 ml/kg/min (mean +/- SEM, p less than 0.05). Plasma triglyceride concentrations fell from 1.9 +/- 0.3 - 1.2 +/- 0.2 mmol/l (mean +/- SEM, p less than 0.05). We conclude that in NIDDs dietary supplementation of omega 3 fatty acids improves in vivo insulin sensitivity and lowers plasma triglyceride levels, while erythrocyte membrane fluidity remains unaltered.

Glycaemic effects of traditional European plant treatments for diabetes. Studies in normal and streptozotocin diabetic mice.

Abstract: Twelve plants used for the traditional treatment of diabetes mellitus in northern Europe were studied using normal and streptozotocin diabetic mice to evaluate effects on glucose homeostasis. The plants were administered in the diet (6.25% by weight) and/or as decoctions or infusions in place of drinking water, to coincide with the traditional method of preparation. Treatment for 28 days with preparations of burdock (Arctium lappa), cashew (Anacardium occidentale), dandelion (Taraxacum officinale), elder (Sambucus nigra), fenugreek (Trigonella foenum-graecum), guayusa (Ilex guayusa), hop (Humulus lupulus), nettle (Urtica dioica), cultivated mushroom (Agaricus bisporus), periwinkle (Catharanthus roseus), sage (Salvia officinale), and wild carrot (Daucus carrota) did not affect the parameters of glucose homeostasis examined in normal mice (basal plasma glucose and insulin, glucose tolerance, insulin-induced hypoglycaemia and glycated haemoglobin). After administration of streptozotocin (200 mg/kg) burdock and nettle aggravated the diabetic condition, while cashew, dandelion, elder, fenugreek, hop, periwinkle, sage and wild carrot did not significantly affect the parameters of glucose homeostasis studied (basal glucose and insulin, insulin-induced hypoglycaemia, glycated haemoglobin and pancreatic insulin concentration). Guayusa and mushroom retarded the development of hyperglycaemia in streptozotocin diabetes and reduced the hyperphagia, polydipsia, body weight loss, and glycated haemoglobin. Mushroom also countered the initial reduction in plasma insulin and the reduction in pancreatic insulin concentration, and improved the hypoglycaemic effect of exogenous insulin. These studies suggest the presence of potentially useful antidiabetic agents in guayusa and mushroom.

Anti-thymocyte globulin and prednisone immunotherapy of recent onset type 1 diabetes mellitus.

Abstract: Increasing evidence that Type 1 (insulin dependent) diabetes mellitus is an autoimmune disease, together with successful cure/prevention in animal models of this disease (e.g. BB/W rat) has led to several trials of immunotherapy in recent onset Type 1 diabetes of man. In this communication we report our experience with short courses of prednisone and antithymocyte globulin (ATGAM) plus prednisone. Prednisone characteristically suppressed Ia positive T lymphocytes into the normal range, but had no long-lasting effect on T-cell phenotype. ATGAM plus prednisone markedly decreased the ratio of T4/T8 ("helper"/"suppressor-cytotoxic") positive T lymphocytes, and this remained suppressed for months. ATGAM treated patients had lower HbA1c on a lower dose of insulin 100 or more days following immune therapy (with 4 out of 5 patients requiring less than 0.2 U/Kg insulin/day). Two patients in the ATGAM treated group did not require insulin for more than 8 months; during remission they had normal fasting blood glucose values, but with abnormal glucose tolerance on oral glucose tolerance testing. Severe, though transient, thrombocytopenia was observed in 2 patients on ATGAM therapy which outweighed its clinical effects.

Prevalence of abnormal thyrotropin concentrations measured by a sensitive assay in patients with type 2 diabetes mellitus.

Abstract: The utilisation of assays for TSH with improved sensitivity has revealed that abnormal TSH results are frequently observed in patients with nonthyroidal illnesses, such as trauma, renal diseases, liver diseases or sepsis. The aim of this study was to investigate the prevalence of abnormal TSH concentrations, using a sensitive immunometric assay, in patients with type 2 (non-insulin-dependent) diabetes mellitus. The study population consisted of 290 type 2 diabetics, 159 females and 131 males aged 40 to 93 years (mean 60.6 +/- 11.9 years), hospitalised because of poor diabetic control or recent-onset diabetes (mean HbA1c value = 9.6 +/- 2.2%). All patients with TSH values outside the normal range (0.45 to 3.66 mlU/l) had FT4 assay and thyroid microsomal autoantibody assay performed on the same specimen of serum. Abnormal TSH concentrations were detected in 91 patients (31.4%). Subclinical hypothyroidism (high TSH, normal FT4) was most common (48.3%), followed by subclinical hyperthyroidism (low TSH, normal FT4) (24.2%) and by definite hypothyroidism (high TSH, low FT4) (23.1%). Definite hyperthyroidism (low TSH, raised FT4) was found in 4 patients (4.4%). None of the patients with low TSH values had increased FT3 concentrations. The prevalence of abnormal thyroid function test results was significantly higher in the female than in the male patients (40.9% vs. 19.8%, p 250 IU/l). Five thyroid microsomal antibody-negative patients had non-autoimmune thyroid diseases, 7 had nonthyroidal illnesses other than diabetes mellitus and 4 were receiving drugs known to affect the hypothalamic-pituitary-thyroid axis. Twenty-seven thyroid microsomal auto-antibody-negative patients with abnormal TSH values (17 with subclinical hypothyroidism and 10 with subclinical hyperthyroidism), who were not receiving drugs known to affect TSH secretion and were free of diseases other than diabetes mellitus, were retested after two months of adequate treatment of diabetes with OHA or insulin. TSH concentrations decreased in all but one patient with initial subclinical hypothyroidism and increased in all patients with initial subclinical hyperthyroidism. These changes were coupled with a significant fall of glycated haemoglobin values. In view of the transient changes in TSH secretion, we suggest that the diagnosis of thyroid dysfunction in type 2 diabetics should be delayed until improvement of the metabolic status.