Tropical pancreatic diabetes in South India: heterogeneity in clinical and biochemical profile

Clinical and biochemical studies were carried out in 33 patients with diabetes secondary to chronic calcific, non-alcoholic pancreatitis (tropical pancreatic diabetes) and in 35 Type 2 (non-insulin-dependent) diabetic patients and 35 non-diabetic subjects. Despite lower body mass indices, only 25% of patients with tropical pancreatic diabetes had clinical evidence of malnutrition. There was no history of cassava ingestion. Mean serum cholesterol concentration was significantly lower in the tropical pancreatic diabetic patients (p less than 0.01) in comparison with the Type 2 diabetic patients or non-diabetic subjects, due to a significantly decreased concentration of LDL cholesterol (p less than 0.01) and VLDL cholesterol (p less than 0.05). Basal and post-glucose stimulated concentrations of serum C-peptide were highest in those pancreatic diabetic patients (n = 11) who responded to oral hypoglycaemic drugs, intermediate in the majority (n = 17), who were insulin dependent and ketosis resistant and negligible in a small sub-group (n = 5) who were ketosis prone. The occurrence of microangiopathy in pancreatic diabetic patients was common and similar to that in Type 2 diabetic patients. Thus, tropical pancreatic diabetes in South India appears to be heterogeneous with respect to level of nutrition, severity of glucose intolerance, B-cell function, response to therapy and the occurrence of microvascular complications.

Ultrasonographic evaluation of the pancreas in tropical pancreatic diabetes

Ultrasonography was performed in three groups of young diabetics in the tropics, namely MODY, IDDM and tropical pancreatic diabetes (TPD). Several morphological abnormalities of the pancreas such as fibrosis and shrinkage of the gland, increased echogenicity and ductal dilatation were found in patients with TPD. It also helped to localize the site of calculi in the pancreas. MODY and IDDM patients did not show any significant changes except a slight reduction in size of the gland. Ultrasonography is a useful tool in differential diagnosis of young diabetics in tropical countries.

HLA, complement C2, C4, properdin factor B and glyoxalase types in South Indian diabetics

A series of diabetic patients from 3 centres in South India have been tested for HLA A, HLA B, BF, C2, C4A, C4B and GLO types. For insulin-dependent diabetes mellitus (IDDM) patients there was a significant increase in HLA B8, of BF F and decrease of C4 A6. No significant variation in HLA, BF, C2 or GLO frequencies was found in non-insulin-dependent diabetes mellitus (NIDDM) patients, but there was a significant decrease in C4B 1 and an increase in C4B 2. The HLA and BF association in South Indian IDDM patients is very different from that reported previously in North India.

C-Peptide responses to glucose load in maturity-onset diabetes of the young (MODY)

Pancreatic beta cell responses were measured in obese and nonobese maturity-onset diabetes of the young (MODY) patients by estimating serum immunoreactive insulin (IRI) and C-peptide (CP) during oral glucose tolerance testing (OGTT). The serum CP responses were generally low in MODY patients and more pronounced in obese patients. The IRI responses were heterogenous; some patients had normal and others low responses. It was observed that in several patients there was a relatively higher IRI concentration in comparison with the CP values, as indicated by low CP and normal IRI values. This is suggestive of altered metabolic fates of insulin and CP in the MODY patients.

Pancreatic beta cell function in offspring of conjugal diabetic parents. Assessment by IRI and C-peptide ratio

Serum C-peptide and insulin responses to oral glucose load were measured in 69 offspring of conjugal diabetic parents (OCDP). The insulin responses were varied. The non obese OCDP showed higher mean insulin levels than non obese controls while the obese OCDP did not have significant differences in the mean insulin responses compared to obese controls. The C-peptide levels were, however, low in both obese and non-obese OCDP. The IRI/CP ratios were elevated in both groups of OCDP. These results suggest that OCDP have low beta cell function and also possibly a change in the metabolism of insulin at the hepatic level, which is more pronounced in non obese OCDP.

Serum uric acid concentrations in offspring of conjugal diabetic parents

Serum uric acid concentrations were measured in offspring of conjugal diabetic parents, in diabetic patients, and in matched nondiabetic controls. The mean uric acid level in offspring of conjugal diabetic parents was significantly higher than in the controls and diabetic patients (P less than 0.001 in the nonobese and P less than 0.05 in the obese). Diabetic patients did not show significant differences in the serum uric acid concentration compared to the controls. The elevated level of serum uric acid in offspring of conjugal diabetic parents could possibly be an early biochemical marker of diabetes.

Hepatic extraction of insulin in non-insulin dependent diabetes. Comparative study of obese and non-obese patients

Changes in the secretion and metabolism of insulin were measured by estimating serum C-peptide and insulin and their ratio during oral GTT in 30 non obese and 12 obese NIDDM patients. The mean IRI and CP responses were low in both groups of patients, compared to weight-matched controls. The reduction in CP was more marked than the reduction in IRI. The molar ratio of insulin and CP was found to be elevated in the patients, probably indicating reduced hepatic and peripheral extraction of insulin. It was noted that the elevated IRI/CP ratio was a 1) a common feature in NIDDM, irrespective of the body weight, 2) it is present even under basal conditions when the insulin levels are the lowest, 3) it appears to be independent of the concentration of insulin reaching the liver, and 4) obese patients appear to have an exaggerated defect compared to their non obese counterparts.

Increased LDL cholesterol in non-insulin-dependent diabetics with maculopathy

Serum cholesterol and its various lipoprotein fractions and triglycerides were measured in 50 non-insulin-dependent diabetic patients, 25 without retinopathy (group A) and 25 with diabetic maculopathy (group B) initially before control of diabetes, and again, after achieving good metabolic control. The lipid parameters were also estimated in 25 healthy non-diabetic subjects. The groups were well matched for sex, age, duration of diabetes and body weight. Mean serum total cholesterol and LDL cholesterol levels were significantly higher in group B when compared to group A, before and after achieving good metabolic control of diabetes (p less than 0.001). Mean total/HDL cholesterol and mean LDL/HDL cholesterol ratios were also significantly increased in group B as compared to group A (p less than 0.01) both before and after good diabetic control in these patients. Mean serum HDL and VLDL cholesterol and triglyceride concentrations were similar in groups A and B. The mean serum lipid concentrations in the diabetic patients without retinopathy (group A) were comparable to those of non-diabetic subjects.

Pinealectomy has no effect on diet-induced thermogenesis and brown adipose tissue proliferation in rats

The role of the pineal gland in diet-induced thermogenesis (DIT) and growth of brown adipose tissue (BAT) in rats during voluntary overfeeding was studied using pinealectomized and sham-pinealectomized rats. Overfeeding was induced by offering the animals a cafeteria-diet (CD) which contained a selection of highly palatable food items. Rats which were fed CD had significantly increased interscapular brown adipose tissue (IBAT) mass and increased tail-skin temperature indicating the importance of the tail in thermoregulation during DIT. Pinealectomy had no effect on the increase in tail-skin temperature and deposition of IBAT, which were stimulated by CD feeding. These findings suggest that the pineal is not directly involved in modulating the metabolism of BAT in rats.

Pancreatic beta-cell function in tropical pancreatic diabetes

Individuals with tropical pancreatic diabetes (TPD) have features of malnutrition and insulin-dependent diabetes but do not exhibit ketosis on withdrawal of insulin. Fasting and postglucose C-peptide responses were assessed in TPD and compared with noninsulin-dependent (NIDDM), insulin-dependent (IDDM), and control groups, matched for body weight. The C-peptide concentrations were lower in TPD in comparison with the controls and NIDDM patients but were significantly higher than in classical IDDM. It is likely that the higher C-peptide is responsible for the ketosis resistance in these patients.

Insulin-specific IgE in serum of 67 diabetic patients against human insulin (Novo), porcine insulin, and bovine insulin. Four case reports

We have investigated the binding of insulin-specific IgE (IgE1) to porcine, bovine, and human insulin (Novo), pancreatic polypeptide, and a-component in serum samples from type I diabetic patients treated with insulin preparations of different purity. Patients treated with porcine or mixed-species purified insulin (monocomponent) did not differ significantly from a nondiabetic control group. Hence, in these groups no IgE1 could be detected against any of the components investigated. Serum samples from patients treated with five-times recrystallized insulin preparations and patients with insulin allergy showed a significantly greater binding of IgE1 to the three species of insulin; IgE1 binding was greatest to bovine insulin and least to human insulin. The difference in binding was most significant in the allergic patients (P less than 0.001), probably due to differences in the affinity. It is concluded that conventional (recrystallized) insulin induces more IgE1 than monocomponent insulin. Data are presented on confirmed allergy in four diabetic patients whose allergy disappeared upon transfer to human insulin.