Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011860 (type 2 diabetes)
 57,723 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Obesity is the most common reason for insulin resistance with consequent hyperinsulinemia. Other reasons for hyperinsulinemia are type II diabetes mellitus and a genetic predisposition with a family history of hypertension. Hyperinsulinemia is considered to cause blood pressure elevation and is generally accepted as an independent risk factor for atherosclerosis. However, insulin per se does not elevate blood pressure, but rather reduces total peripheral vascular resistance in experimental studies. Blood pressure might be elevated by other mechanisms secondary to hyperinsulinemia, however, such as enhanced renal sodium retention, elevated intracellular free calcium, and increased activity of the sympathetic nervous system. Indeed, subjects whose blood pressure is salt-sensitive exhibit hyperinsulinemia after glucose loading, and normotensive subjects with glucose-induced hyperinsulinemia will develop hypertension within 5 years more often than normoinsulinemic subjects. In primary hypertension, the incidence of insulin resistance and hyperinsulinemia is much higher than in normotensive controls. However, not all reported studies show a relationship between hyperinsulinemia and blood pressure elevation, and in some experimental studies no blood pressure elevation could be induced by prolonged hyperinsulinemia. Therefore, it is still unclear whether hyperinsulinemia induces hypertension or is only casually associated with it. Nevertheless, treatment of hyperinsulinemia is recommended to avoid secondary complications. Treatment should begin with weight reduction and physical exercise, which will improve insulin resistance. Hypertension benefits more from weight reduction than from exercise. If drug therapy of hypertension is required, angiotensin-converting enzyme (ACE) inhibitors and calcium-channel blockers are the drugs of first choice. In addition, beta-blockers and centrally acting drugs appear to be of certain benefit. However, diuretics must be used carefully, because they ameliorate insulin resistance, induce dyslipoproteinemia, and stimulate the sympathetic nervous system.
 ...
PMID:Hyperinsulinemia, insulin resistance, and hypertension. 789 93

Plasma levels of endothelin (ET) and atrial natriuretic peptide (ANP) are known to be elevated in patients on chronic hemodialysis. Since ET and ANP plasma levels are found to be raised in nonuremic diabetic versus nondiabetic subjects, we wanted to detect a possible difference in plasma levels of these hormones in diabetic versus nondiabetic patients who were on chronic renal replacement therapy. ET is a possible marker of increased vascular atherogenic activity. We measured plasma levels of ET and ANP pre- and posthemodialysis in 23 non-insulin-dependent (NIDDM) diabetic versus 23 nondiabetic patients who were matched according to age and time of day of hemodialysis, and who did not show clinical signs of overt cardiac decompensation. Mean plasma levels of ET and ANP did not differ in diabetic from nondiabetic patients, neither pre- nor postdialysis. In both patient groups, mean ET levels were twice the upper normal limit, did not change significantly pre- versus postdialysis, and did not correlate with blood pressure or with volume ultrafiltration during dialysis. Calcium channel blocker therapy was accompanied by a significant rise of ET pre- and postdialysis in nondiabetic patients but not in diabetic patients. In diabetic patients, ET plasma levels correlated positively with fructosamine levels as an indicator of short-term blood glucose control. Mean ANP plasma levels were about three times the upper normal limit and decreased significantly during dialysis, but this decrease correlated neither with volume ultrafiltration nor with blood pressure. In conclusion, we could not find a difference in plasma levels of ET and ANP for diabetic versus nondiabetic dialysis patients, but impaired short-term blood glucose control in diabetic and calcium channel blocker therapy in only nondiabetic dialysis patients showed concomitant increases in plasma ET levels and thus possibly different mechanisms of ET regulating pathways.
 ...
PMID:Endothelin and atrial natriuretic peptide in non-insulin-dependent diabetic versus nondiabetic patients on chronic hemodialysis. 789 86

The Nova ISE for IMg2+ was utilized to examine IMg2+ in plasma and serum of patients with a variety of pathophysiologic and disease syndromes (e.g., long-term renal transplants [LTRT], during and before cardiac surgery, migraine headaches, head trauma, pregnancy, chronic fatigue syndrome [CFS], non-insulin dependent diabetes mellitus [NIDDM], asthma and after excessive dietary intake of Mg). The results indicate that LTRT treated with cyclosporin A, migraine, head trauma, pregnancy, NIDDM, diseased pregnant, and asthmatic patients all on the average, exhibit significant depression in IMg2+ but not total Mg (TMg). Patients with CFS failed to exhibit changes in serum IMg2+ or TMg levels. Increased dietary load of Mg, for only 6 days, resulted in significant elevations of serum IMg2+ but not TMg. Correlations between the clinical course of several of these syndromes and the fall in IMg2+ were found. The Ca2+/Mg2+ ratio appears to be an important guide for signs of peripheral vasoconstriction and or spasm and possibly enhanced atherogenesis. Overall, the data point to important uses for ISE's for IMg2+ in the diagnosis and treatment of disease states.
 ...
PMID:Clinical studies with the NOVA ISE for IMg2+. 793 86

Calcium channels play an important role in insulin secretion from pancreatic beta cells, in which two different L-type voltage-dependent Ca2+ channels (VDCC), the beta cell/neuron type and the cardiac type are expressed. The former pre-dominant subtype gene (hCa CN4) consists of 49 exons spanning 120 kilo-bases. The promoter region of hCaCN4 is similar to that of housekeeping gene, which is extremely G+C rich and lacks a TATA-like sequence but has three possible binding regions for transcriptional factor Sp1. Changes of calcium channel mRNA in rat pancreatic islets after glucose infusion are introduced. It is important to investigate variations or mutations in the hCaCN4 gene, causing insufficient insulin secretion, leading to NIDDM.
 ...
PMID:[The alpha 1 subunit of voltage-dependent calcium channel expressed in pancreatic beta cells]. 798 84

Coeliac disease occurs more commonly in children with insulin-dependent diabetes mellitus (IDDM) than in the general population, but the prevalence of coeliac disease in adults with diabetes is unknown. We therefore screened an adult hospital-based diabetic population using IgA antigliadin antibody (IgA-AGA) to identify those patients requiring intestinal biopsy. In 1 year, 1789 patients (43% IDDM, 57% NIDDM) were screened, and 73 had raised IgA-AGA. Of these patients, 49 agreed to duodenal biopsy and 13 (10 IDDM) had coeliac disease. Selective IgA deficiency was found in eight patients, one of whom had coeliac disease. Of these 14 patients with newly diagnosed coeliac disease, four had microcytic anaemia, nine a low serum ferritin, and four a low albumin-corrected calcium. Eight patients had symptoms which improved on gluten withdrawal. Dietary compliance was maintained in 6/8 symptomatic patients, but only in 1/6 without symptoms. Included in the 1789 patients were four (all IDDM) with known coeliac disease. The overall prevalence of coeliac disease in adult patients with IDDM was 1:50 compared with 1:340 in NIDDM. Coeliac disease is common in adults with IDDM and may cause malabsorption and ill health. It should be suspected in any IDDM patient with gastrointestinal symptoms or unexplained anaemia.
 ...
PMID:The prevalence of coeliac disease in adult diabetes mellitus. 798 59

Non-insulin-dependent diabetes mellitus (NIDDM) is a metabolic disease associated with abnormal insulin secretion, the underlying mechanisms of which are unknown. Glucose-dependent signal transduction pathways were investigated in pancreatic islets derived from the db/db mouse, an animal model of NIDDM. After stimulation with glucose (4-12 mM), the changes in intracellular Ca2+ concentration ([Ca2+]i) were different; unlike control islets, db/db islets lacked an initial reduction of [Ca2+]i and the subsequent [Ca2+]i oscillations following stimulation with 12 mM glucose. The severity of these defects in Ca2+ signaling correlated with the age-dependent development of hyperglycemia. Similarly defective glucose-induced Ca2+ signaling were reproduced in control islets by pre-exposure to thapsigargin, a selective inhibitor of endoplasmic reticulum (ER) Ca(2+)-ATPase. Estimation of ATPase activities from rates of ATP hydrolysis and by immunoblot hybridization with an antiserum directed against the sarco/endoplasmic reticulum Ca(2+)-ATPase both demonstrated that the ER Ca(2+)-ATPase was almost entirely absent from db/db islets. The effects of inhibition of ER Ca(2+)-ATPase on insulin secretion were also examined; a 4-day exposure of control islets to 1 microM thapsigargin resulted in basal and glucose-stimulated insulin secretion levels similar to those found in db/db islets. These results suggest that aberrant ER Ca2+ sequestration underlies the impaired glucose responses in the db/db mouse and may play a role in defective insulin secretion associated with NIDDM.
 ...
PMID:Defective glucose-dependent endoplasmic reticulum Ca2+ sequestration in diabetic mouse islets of Langerhans. 803 70

The plasma membrane enzyme (Ca2+ + Mg2+)-adenosine triphosphatase (ATPase) is hormonally regulated and may participate in Ca2+ signaling by removing excess Ca2+ from the cell. Therefore, observations of a hormone-specific loss of insulin stimulation of ATPase in kidney membranes from non-insulin-dependent diabetic (NIDDM) rats may reflect their insulin-resistant state. Consequently, to evaluate whether additional insulin-resistant conditions are associated with impaired function of ATPase and with loss of regulation of the enzyme by insulin, studies were extended to investigate (Ca2+ + Mg2+)-ATPase activities and hormonal regulation of the enzyme in kidney basolateral membranes from obese and lean Zucker rats. (Ca2+ + Mg2+)-ATPase activity was lower in membranes from obese rats compared with lean rats. Maximal velocity (Vmax) of the enzyme activity was 29.2 +/- 2.6 nmol Pi/mg/min in obese rats versus 57.2 +/- 6.5 in lean rats (P < .05). However, the affinity of the enzyme for Ca2+ was similar in obese and lean rats (Km Ca2+, 0.23 +/- 0.025 v 0.23 +/- 0.032 mumol/L Ca2+). Also, the Km for ATP of the enzyme was similar in membranes from obese and lean rats. Insulin, parathyroid hormone (PTH), and cyclic adenosine monophosphate (cAMP) stimulated the ATPase activity in membranes from lean rats in a dose-dependent manner (15% to 28%). Also, the protein kinase C (PKC) stimulator 12-O-tetradecanoyl phorbol-13-acetate (TPA) increased the ATPase activity in membranes from lean rats.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Decreased activity of (Ca2+ + Mg2+)-adenosine triphosphatase (ATPase) and a hormone-specific defect in insulin regulation of ATPase in kidney basolateral membranes from obese fa/fa rats. 805 47

Association between insulin resistance and hypertension: Insulin resistance and reactive hyperinsulinemia occur not only with obesity, impaired glucose tolerance or non-insulin-dependent (type 2) diabetes mellitus, but also in many non-obese, non-diabetic patients with essential hypertension and their currently normotensive, lean young offspring and in some other conditions known to promote hypertension. Insulin resistance impairs glucose tolerance, while insulin resistance and/or hyperinsulinemia promote dyslipidemia, body fat deposition and probably atherogenesis. Therefore, the common coexistence of a genetic predisposition for hypertension with insulin resistance helps to explain the frequent, although temporally often dissociated, occurrence of hypertension as well as dyslipidemia, obesity and type 2 diabetes in a given subject. Pathogenetic mechanisms: In the pathogenesis of hypertension, inappropriate vasoconstriction (due to dysbalance of vasoactive substances and/or raised cytosolic Ca2+) and/or a structural vasculopathy is a very important ultimate causative event. In the presumed mosaic of participating pressor mechanisms, distinct Na+ retention is almost obligatory with diabetes mellitus, while essential and particularly obesity-associated hypertension probably involves a tendency for sympathetic activation. Development of insulin resistance: Insulin resistance may develop as a consequence of an intracellular excess of Ca2+ or decrease in Mg2+, an impaired insulin-mediated rise in skeletal muscle blood flow, increased sympathetic activity or being overweight. Acute hyperinsulinemia on the one hand causes arterial vasodilation and on the other hand enhances renal sodium reabsorption and sympathetic activity. Chronically, hyperinsulinemia may promote cardiovascular muscle cell proliferation and atherogenesis, and it has been proposed that insulin resistance in certain transmembranous cation exchange systems may elevate cytosolic Ca2+. Nevertheless, whether insulin resistance and/or hyperinsulinemia itself contribute to the pathogenesis of hypertension is still unclear.
 ...
PMID:Insulin resistance, hyperinsulinemia and hypertension. 815 79

The plasma membrane enzyme (Ca2+ + Mg2+)-adenosine triphosphatase [(Ca2+ + Mg2+)-ATPase] is hormonally regulated, and may participate in Ca2+ signaling by removing excess Ca2+ from the cell. Insulin increases ATPase activity in kidney cortical basolateral membranes (BLM) from normal rats, but fails to do so in membranes from insulin-resistant non-insulin-dependent diabetic (NIDDM) rats. To investigate mechanisms of insulin regulation of ATPase and to evaluate whether the loss of this regulation in diabetes is hormone-specific and depends on blood glucose levels, (Ca2+ + Mg2+)-ATPase function and its hormonal regulation were studied in kidney BLM from rats with mild and severe NIDDM. Km values for ATP and Ca2+ affinity of the ATPase were similar in diabetic and control rats, but the maximal velocity (Vmax) of the enzyme was higher in diabetic groups. Insulin, the protein kinase C (PKC) stimulator 12-0-tetradecanoylphorbol 13-acetate (TPA), parathyroid hormone (PTH), and cyclic adenosine monophosphate (cAMP) all increased the ATPase activity in BLM from controls by increasing the enzyme's affinity for Ca2+. A protein kinase A (PKA) inhibitor (H8 in low concentrations) abolished cAMP and PTH effects, but not those of insulin, whereas the PKC inhibitors (sphingosine and high concentrations of H8) did abolish the effects of insulin. Stimulations of ATPase activity by insulin and by PTH and cAMP were additive. Insulin and TPA lost their stimulatory effects on ATPase in BLM from rats with either mild or severe NIDDM, but PTH and cAMP maintained their stimulatory effects in these membranes. The data show [1] (Ca2+ + Mg2+)-ATPase activity is increased in NIDDM, and a hormone-specific loss of insulin stimulation of ATPase occurs; (2) these defects are not dependent on the level of glycemia; and (3) the stimulatory effects of insulin on the ATPase may be mediated in part via PKC. We suggest that the hormone-specific defect in insulin regulation of ATPase seen in the NIDDM rats may contribute to their insulin resistance.
 ...
PMID:Hormone-specific defect in insulin regulation of (Ca2+ + Mg2+)-adenosine triphosphatase activity in kidney membranes from streptozocin non-insulin-dependent diabetic rats. 817 49

During the period between January 1981 and December 1992, a total of ten patients with pathologically confirmed insulinoma were studied. All patients presented with variable degrees of neuroglycopenic symptoms and Whipple's triad. The ratio of insulin to glucose after an overnight fast was greater than 0.3 in 90% (9/10) of patients. Eight patients who received supervised fasting developed neuroglycopenia with relative hyperinsulinemia within 48 hours of fasting. Four of 8 patients developed hypoglycemia during a 5-hour oral glucose tolerance test (OGTT). Calcium infusion test was more sensitive in patients with an initially higher plasma glucose. The detection rates of various localization studies were 12.5% (1/8) by abdominal ultrasonography, 37.5% (3/8) by abdominal CT scan, 50% (5/10) by selective superior mesenteric and celiac arteriography. Transhepatic portal venous sampling (THPVS) detected insulinomas in 4 of 4 cases. Endoscopic ultrasonography and intraoperative ultrasonography were performed on 1 and 2 cases respectively, and were able to localize the lesions successfully. All patients received surgical treatment including enucleation (n = 2), subtotal pancreatectomy (n = 3) and distal pancreatectomy (n = 5). All patients had single tumors which were all benign islet cell adenomas. The mean size of the tumors was 15.5 +/- 2.0 mm in diameter (range: 8 to 30 mm) and mainly located in the body (50%) and tail (40%), only 1 in the pancreatic head. All symptoms of hypoglycemia subsided after operation. Hyperglycemia was observed in all patients immediately after operation, and most of them resumed normoglycemia within 8 days. However, the 2 patients who had impaired OGTT preoperatively had persistent hyperglycemia after operation and therefore were diagnosed as having diabetes (NIDDM).
 ...
PMID:Insulinoma--clinical experience in ten cases. 820 95


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>