Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin accelerates the entry of glucose and amino acids into muscle cells by acting upon the 'carrier-facilitated' transport mechanism. For glucose this process is passive and leads to equilibration of intracellular and extracellular concentrations. In heart muscle, glucose transport is a rate-limiting step for glucose uptake. During hypoxia and ischemia the heart turns to anaerobic glycolysis for energy production and therefore, maximal glucose transport becomes important. Insulin is necessary to insure proper protein synthesis, probably at the level of membrane-bound polyribosomes. However, during myocardial hypoxia, insulin alone cannot restore the associated depression in protein synthesis. Although insulin hyperpolarizes the cell, a change in the ratio of intracellular to extracellular activities of potassium is not its primary mode of action. An insulin-induced configurational change in the plasma membrane could simultaneously account for the effects of insulin on sodium and potassium permeability and the action on facilitated transport. Intracellular levels of cyclic adenylate may be reduced by insulin in adipose tissue because of inhibition of adenyl cyclase or stimulation of phosphodiesterase. However, at this time there is little evidence that insulin alters cyclic AMP levels in the heart. Insulin secretion is depressed in patients with heart disease in proportion to the reduction of cardiac index sustained. Since the ischemic heart is dependent upon glucose as the major fuel, insulin lack may deprive the heart of adequate substrate.
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PMID:Insulin: fundamental mechanism of action and the heart. 18 67

A prospective study to determine if subcutaneous edema interferes with insulin absorption was performed. Forty-six patients entered the study. Three groups were formed. Twenty patients with generalized edema (Group 1), ten of them with non-insulin dependent diabetes mellitus (NIDDM). Twenty patients without edema (Group II). 10 of them with NIDDM; and six patients with mild edema (Group III). The disappearance of I125-insulin was measured throughout 360 minutes. The rate of absorption in group I was significantly lower and delayed than in group II. The amount of insulin absorbed at 360 minutes was 3 to 4 fold lower in group I than in group II (p 0.001). Group III had intermediate values. The peak of plasma I125-insulin level was 3 to 4 fold lower in group I than group II. The impairment of insulin absorption in subjects with edema was more evident in those with NIDDM. In conclusion, this study demonstrates that subcutaneous edema impairs insulin absorption. Insulin absorption from subcutaneous tissue varies due to several conditions, resulting in a difficult glycemic control. Previous studies have shown that insulin absorption is affected by several factors as the site of injection, room and skin temperature, physical exercise, the thickness of adipose tissue, local massage, and local degradation of insulin. Edema due to chronic complications such as nephropathy and cardiopathy often occurs in long-standing diabetic subjects. However, the effects of edema of the skin and subcutaneous tissue on insulin absorption has not been previously examined. The aim of this study was to assess if edema affects the absorption of insulin.
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PMID:Delayed insulin absorption due to subcutaneous edema. 181 99

The discovery of insulin in 1922 aroused immediate clinical interest in its use in heart disease. In severe heart failure, insulin release is suppressed by the combined effect of poor pancreatic perfusion and by increased sympathetic activity. In these circumstances, myocardial metabolism of glucose may break down through the deficiency of insulin. Because of this, glucose, insulin and potassium solution (GIK solution) has been used in cardiopulmonary resuscitation. However, its mechanism is not yet fully known. This study was designed to determine the effect of insulin on cardiac muscle at various temperatures. The mechanical response of papillary muscle isolated from guinea pig ventricle was observed under various thermal conditions (23-37 degrees C). Twitch tension was increased by the administration of 0.2 I.U./ml insulin under each thermal condition. In all circumstances, the increase in contractile force was noted about 2 min after the administration of insulin. The effect of insulin on 20 preparations demonstrated the mean maximum contractile force was 226% ( +/- 34 S.D., n = 5) in 37 degrees C, 194% ( +/- 36 S.D., n = 5) in 30 degrees C, 190% ( +/- 30 S.D., n = 5) in 27 degrees C and 200% ( +/- 36 S.D., n = 5) in in 23 degrees C. The differences between different temperatures was not significant. The effect of insulin during depression Na-K pump by high concentration of ouabain (g-strophanthin, 10(-5) M) was also observed. Insulin (0.2 I.U./ml) was administered when the papillary muscle showed no response to electrical stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Response of isolated guinea pig myocardium to insulin therapy during normothermia and graded hypothermia. 242 78

A follow-up study of 1939 diabetic patients with a mean observation period of 9.4 years was carried out in Osaka, Japan. The mortality rates per 1000 person-years were 31.35 for males and 21.99 for females, and the ratios of observed to expected number of deaths were 1.69 for males and 1.74 for females, indicating an excess mortality for diabetic patients of both sexes and higher mortality in males than in females in Japan. Factors related to the prognosis of the patients were age, elevated fasting glucose level, lower obesity index, hypertension, diabetic retinopathy, and albuminuria at entry to the study. Insulin treatment was also associated with poor prognosis. Cerebro-cardiovascular and renal disease were the major causes of death in diabetic patients; heart disease killed 19.5%, cerebrovascular disease 16.7% and renal disease 13.1%. The relatively high frequency of renal disease as a cause of death in type 2 diabetes, especially in patients with a lower age of onset, was noteworthy, suggesting some difference in the clinical manifestations of diabetes between Japan and Western countries. Malignant neoplasms accounted for 25% of deaths, and cirrhosis of the liver for 6.4%.
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PMID:Mortality and causes of death in type 2 diabetic patients. A long-term follow-up study in Osaka District, Japan. 275 88

One of the leading causes of mortality in diabetics is myocardial disease. In the past few years this subject has generated a significant amount of interest with the result that myocardial problems associated with diabetes are far better understood. Though originally thought to occur as a result of atherosclerosis, various studies have shown that heart disease can occur in the absence of atherosclerosis, suggesting a diabetic cardiomyopathy. Using diabetic animals, it has been possible to characterize diabetes-induced myocardial abnormalities. Diabetic rat hearts do not respond to conditions of high stress as well as controls. The functional depression is accompanied by altered cardiac enzyme systems. A decrease in myosin ATPase activity which appears to be a result of diabetes-induced hypothyroidism is seen. Also, a depression of sarcoplasmic reticular calcium ATPase, along with a depression of calcium uptake by the SR, is seen in diabetic rat hearts. Na+, K+ ATPase activity has also been shown to be depressed and the depression appears to correlate with depressed atrial contractility. High levels of circulating fats in diabetics may alter the integrity of membranes leading to altered enzyme activities. Insulin treatment has been relatively successful at reversing or preventing myocardial changes in the diabetic rat. Other treatments that have been studied include thyroid hormone treatment, since the depression of myosin ATPase can be corrected by such treatment; and carnitine treatment, as the elevation of long chain acyl carnitines (LCAC) and the resulting depression of calcium uptake in the SR can be so normalized. These treatments have not been successful at normalizing cardiac function. A combination of the two treatments normalized function only partially, suggesting that factors besides myosin ATPase and SR calcium uptake are involved. Other treatments that have been tried include vanadate, methyl palmoxirate, and choline and methionine. Vanadate treatment has proved to be encouraging in that it normalizes both function and hyperglycemia. Methyl palmoxirate, a fatty acid analog, normalized only the elevation of LCAC but did not affect function. Methionine and choline were only partially successful in preventing the functional alterations of diabetic rat hearts. The purpose of the present article is to review our understanding of diabetes-induced myocardial problems and their possible causes. Findings from our laboratory and others are described in which attempts have been made to normalize cardiac function.
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PMID:Diabetes-induced abnormalities in the myocardium. 293 41

Since the introduction of insulin, heart disease has become a major impediment to survival in persons with diabetes mellitus. Coronary disease has increased severity and accelerated development in diabetic persons compared with an age- and sex-matched nondiabetic population. A peculiar vulnerability of women to the influence of diabetes with loss of premenopausal coronary disease protection has been found. The symptomatology of coronary events may differ and coronary care data show a higher incidence of sudden death in diabetic patients who have a myocardial infarction than in their non-diabetic counterparts. Insulin may play a role in the myocardial adjustment to an ischemic insult by enhancing glucose intake and suppressing lipolysis and ketogenesis. Carbohydrate intolerance in dogs, rhesus monkeys and humans appears associated with similar histologic and compositional changes in the myocardium. Abnormalities in diastolic ventricular function not attributable to large- or small-vessel coronary disease have been found in the diabetic subjects of each species. Studies in humans who have diabetes have assessed single pressure-volume relationships and more exacting measures of ventricular compliance are needed. Abnormalities of myocardial function in patients with diabetes have been found using echo and radionuclide techniques. Many of these findings need to be correlated with invasive data or confirmed in larger populations. Autonomic dysfunction is common in diabetic persons and may imply an associated poor prognosis. Reflex abnormalities in parasympathetic function are most prevalent and occur before sympathetic dysfunction.
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PMID:The heart in diabetes. 637 49

A systematic 20-year follow-up study of 1,221 diabetic patients was carried out in Osaka, Japan. The mean annual mortality rates were 2.55% for men and 1.64% for women. The ratios of observed to expected numbers of deaths were 1.50 for men and 1.39 for women, indicating an excess mortality for diabetic patients of both sexes, and higher mortality in men than in women. Factors that predisposed diabetic patients to premature death were early age of onset, albuminuria, diabetic retinopathy and fasting glucose level greater than 11.1 mmol/l at the initial examination. Insulin dependence was also associated with poor prognosis. Cerebro-cardiovascular and renal diseases were the major causes of death in the diabetic patients; heart disease was the cause of death in 16.9%, cerebrovascular disease in 16.4% and renal disease in 11.9%. The relatively high incidence of renal disease as cause of death in diabetic patients was striking. Malignant neoplasms of liver and of pancreas and cirrhosis were also associated with increased ratio of observed to expected number of deaths in the patients.
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PMID:A long-term follow-up study of Japanese diabetic patients: mortality and causes of death. 664 95

The association between the lack of adrenergic symptoms during hypoglycemia and myocardial 123I-metaiodobenzylguanidine (MIBG) accumulation was investigated in 12 insulin-treated non-insulin-dependent diabetes mellitus (NIDDM) patients who had no evidence of heart disease. These patients were divided into 2 groups according to the presence (group A) or absence (group B) of adrenergic symptoms during hypoglycemia. Autonomic function tests revealed significantly severe autonomic dysfunction in group B compared to that in group A. Insulin infusion test indicated no significant difference in the catecholamine response between the two groups. 123I-MIBG scintigraphy showed that the heart/mediastinum ratio of MIBG uptake was significantly lower, and scintigraphic defect was greater in group B than in group A. There were no significant differences in the washout rate between the two groups. These results suggested that the lack of adrenergic symptoms during hypoglycemia may be associated with cardiac sympathetic nervous dysfunction in insulin-treated NIDDM patients, and this dysfunction is mainly due to cardiac sympathetic denervation.
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PMID:Evaluation of cardiac sympathetic nervous function by 123I-metaiodobenzylguanidine scintigraphy in insulin-treated non-insulin dependent diabetics with hypoglycemia unawareness. 868 Jan 9

Insulin resistance and impaired insulin secretion are thought to be the primary defects in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM). Disproportionately increased proinsulin relative to insulin levels are suggested to be an early indicator of a failing pancreas. We examined the relationship of fasting specific insulin, proinsulin, and 32, 33 split proinsulin concentrations, and the proinsulin: insulin ration to the risk of developing NIDDM 3.5 years later in 65-74-year-old non-diabetic Finnish subjects participating in a population-based study (n=892) on diabetes and heart disease. Altogether 69 subjects developed NIDDM over a 3.5-year follow-up (cases). The cases were compared to randomly-selected gender-matched control subjects (n=69) and control subjects matched for gender, glucose tolerance status (normal or impaired), and body mass index (n=69). There were no differences in insulin concentrations between cases and random or matched control subjects [median and interquartile range: 123 (77-154), 108 (74-143), 118 (83-145) pmol/l, p=0.271]. Random control subjects had lower proinsulin and 32, 33 split proinsulin concentrations and split proinsulin: insulin ratios compared to cases [5.7 (3.8-9.0) vs 7.3 (4.8-10.0) pmol/l, p=0.005; 7.3 (4.5-13.0 vs 10.4 (7.1-18.0) pmol/l, p=0.002; 0.073 (0.057-0.110) vs 0.097 (0.060- 0.135), p=0.003]. Matched control subjects had lower proinsulin concentrations and proinsulin: insulin ratios compared to cases [5.9 (4.0-7.7) vs 7.3 (4.8-10.0) pmol/l, p=0.019; 0.048 (0.035-0.071) vs 0.064 (0.045-0.100), p=0.008]. When cases were compared to matched control subjects a 1 SD increase in baseline proinsulin: insulin ratio was associated with a 1.37-fold risk (p=0.020) of developing diabetes. Moreover, this association was independent of fasting glucose concentration at baseline. Thus, in elderly prediabetic subjects disproportionately increased proinsulin concentration, an indicator of defective insulin secretion, is associated with conversion to diabetes over a short time period.
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PMID:Serum proinsulin levels are disproportionately increased in elderly prediabetic subjects. 869 Jan 69

Abnormalities of glucose, insulin, and lipoprotein metabolism are common in patients with hypertension. This constellation of risk factors may be recognized at a young ages and is, at least in part, inheritable. Insulin resistance and compensatory hyperinsulinemia may be primary events, and enhanced sympathetic activity and diminished adrenal medullary activity could be important links between the defect in insulin action and the development of hypertension and the associated metabolic abnormalities. But not all hypertensive patients have insulin resistance. It is possible that insulin resistance, and compensatory hyperinsulinemia have major roles in the regulation of blood pressure in susceptible subjects predisposed to hypertension by hereditary or environmental factors. Considerable evidence, both in experimental animal models and in humans, points to hypertension as being of critical importance in the pathogenesis of severe diabetic heart disease. In diabetic hypertensive cardiomyopathy, coronary artery disease as well as structural and functional abnormalities are more pronounced than would be expected from either process alone. The hypertension increases the risk of diabetic nephropathy in non-insulin-dependent diabetic patients. Microalbuminuria is a powerful predictor of mortality in these patients. It seems that angiotensin-converting-inhibitors have efficacy in postponing nephropathy in hypertensive non-insulin-dependent diabetic patients. In patients with hypertension and diabetes, additional clinical trials are required to identify the interventions that will most effectively reduce not only overall risk but also improve cardiovascular disease prognosis.
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PMID:[Arterial hypertension and disorders of hydrocarbon metabolism]. 988 63


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