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

A 49-year-old man with an 11 year history of NIDDM presented hypercalcemic and with acute on chronic renal failure. His only symptoms were mild anorexia and nausea. Four years previously he had been diagnosed as having lipoid pneumonia, with classical histological findings. On this admission, serum parathyroid hormone was suppressed and 1,25 dihydroxyvitamin D levels elevated. The cause of his hypercalcemia presumably was ectopic 1 hydroxylation of 25 hydroxyvitamin D in the chronic granulomata in his lungs. It should be emphasised that any chronic granulomatous disease, and not just sarcoidosis, may be a cause of hypercalcemia.
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PMID:Hypercalcemia and lipoid pneumonia. 263 65

Recent studies indicate that serum levels of osteocalcin, a 49-aminoacid bone matrix protein, are a biochemical marker of bone formation. In order to study bone metabolism in diabetes mellitus, in 28 patients with Type 1 (insulin-dependent) diabetes mellitus, in 38 patients with Type 2 (non-insulin-dependent) diabetes mellitus and two control groups, matched for Type 1 and Type 2 diabetic patients, respectively, serum levels of osteocalcin, parathyroid hormone and 25 hydroxy vitamin D were measured by radioimmunoassay. Whereas in Type 1 diabetic patients and control subjects serum levels of osteocalcin and 25 hydroxy vitamin D were not statistically different, serum osteocalcin and 25 hydroxy vitamin D levels were significantly decreased in Type 2 diabetic patients when compared with corresponding control subjects (p less than 0.03 and p less than 0.001, respectively). Independent of the type of diabetes, serum parathyroid hormone levels were comparable in diabetic patients and matched control subjects. Serum osteocalcin levels were significantly lower in Type 1 diabetic patients with retinopathy and/or proteinuria than in Type 1 diabetic patients without microangiopathy (p less than 0.05). Whereas serum parathyroid hormone levels in Type 2 diabetic patients with retinopathy and/or proteinuria were significantly increased (p less than 0.02), 25 hydroxy vitamin D levels were decreased (p less than 0.02) when compared with Type 2 diabetic patients without microangiopathy. Our data give evidence of a vitamin D deficiency and a decreased bone formation in patients with Type 2 diabetes mellitus. In Type 1 diabetes mellitus bone formation as reflected by serum osteocalcin levels is influenced by the presence or absence of microangiopathic complications.
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PMID:Serum osteocalcin levels in diabetes mellitus: analysis of the type of diabetes and microvascular complications. 326 86

The effect of mild, non-insulin-dependent diabetes (NIDDM) on bone calcification and calcium (Ca) homeostasis was studied in growing rats (males and females). The diabetic state was characterized by mild insulin deficiency, plasma levels being 73% of controls, and mild hyperglycemia, with nonfasting plasma glucose levels of 1.5 times normal. There was no difference in plasma levels of Ca, phosphate (Pi), magnesium (Mg), alkaline phosphatase, immunoreactive parathyroid hormone (iPTH), calcitonin, 25-(OH)vitamin D (25[OH]D), 1,25-dihydroxyvitamin D (1,25[OH]2D), and 24,25-dihydroxyvitamin D (24,25[OH]2D) between the NIDDM rats and their controls of either sex. Metabolic Ca and Pi balance studies revealed that the experimental animals of both sexes were in positive Ca and Pi balance similar to that of their controls. Histologic studies of the kidney and intestinal slices from the experimental group were normal. Ca and Pi bone content calculated per gram bone ash of the femur, mandible, and second and fourth caudal vertebrae, and the organic content in the bones of the NIDDM animals showed no difference from their controls. Femur bone density and tibial epiphyseal growth plate width and morphology were similar histologically in the experimental and control rats. No decreased osteoid content in the tibial bone was found in the diabetic rats compared with controls. Physiologic sex differences, consisting of lower plasma Pi, higher plasma calcitonin levels, increased ratio of femur dry bone weight to total body weight, and increased percentage of mineralized and total bone volume at the tibial metaphysis seen in female compared with male control rats were also seen in the diabetic animals.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Bone calcification and calcium homeostasis in rats with non-insulin-dependent diabetes induced by streptozocin. 397 85

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)
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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

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.
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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

Patients with poorly controlled noninsulin dependent diabetes mellitus (NIDDM) are shown to have higher bone mass. However, the influence of changes in glycemic control on bone turnover is not known. To clarify whether metabolic improvement of poorly controlled NIDDM affects bone turnover, markers for glucose, mineral, and bone metabolism were assessed before and after glycemic control for 3 weeks in 78 poorly controlled NIDDM patients with initial hemoglobin A1c over 8%. Metabolic improvement caused a reduction in urinary calcium (Ca) and phosphate (Pi) and serum 1,25(OH)2D levels, and an increase in serum Pi without changes in serum Ca or parathyroid hormone levels. Bone resorption markers, urinary deoxypyridinoline (Dpd) and type I collagen carboxy-terminal telopeptide (CTx), as well as a bone formation marker, serum bone type alkaline phosphatase (BALP), were reduced. However, another bone formation marker, serum osteocalcin (OC), was low before treatment and was elevated after treatment. The decrease in Dpd, CTx and BALP, but not the increase in OC, correlated with each other and with the improvement in glycemic indices. In conclusion, metabolic improvement of poorly controlled NIDDM decreases bone turnover within a short period. Thus, glycemic control may protect NIDDM patients from bone loss. It is possible that serum OC is affected by hyperglycemia per se, and may not correctly reflect bone turnover.
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PMID:Metabolic improvement of poorly controlled noninsulin-dependent diabetes mellitus decreases bone turnover. 928 19

Osteoblast deficit plays a principal role in the development of diabetic osteopenia. We have previously reported that high glucose conditions impair the function of osteoblast-like MG-63 cells. This study was performed to assess the sensitivity of osteoblasts to 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in patients with type 2 diabetes without insulin deficiency or overt diabetic complications. During stimulation with 1,25(OH)2D3 at 2.0 micrograms/day for 6 consecutive days in 9 type 2 diabetic patients, serum levels of bone alkaline phosphatase (BALP), osteocalcin (OC) and the carboxyterminal propeptide of type 1 procollagen, and the urinary excretion of pyridinoline and deoxypyridinoline (DPYR), were monitored. As parameters of glycemic control, the mean level of fasting plasma glucose (mFPG) throughout the 1,25(OH)2D3 stimulation test and the level of HbA1C were used. 1,25(OH)2D3 increased serum 1,25(OH)2D significantly by day 2, which was followed by a significant reduction in the serum level of intact parathyroid hormone. The maximal increment of serum OC adjusted for that of 1,25(OH)2D was negatively correlated with both mFPG and HbA1C levels (p < 0.05). Furthermore, the magnitude of 1,25(OH)2D3-induced bone resorption, as reflected by the maximal increase in urinary DPYR excretion, was negatively correlated with the mFPG level (p < 0.05). Basal BALP tended to be negatively correlated with HbA1C, although not to a significant extent. In conclusion, our findings would indicate that poor glycemic control impairs the responses of osteoblasts and osteoclasts to 1,25(OH)2D3 in normo-insulinemic type 2 diabetic patients.
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PMID:Poor glycemic control impairs the response of biochemical parameters of bone formation and resorption to exogenous 1,25-dihydroxyvitamin D3 in patients with type 2 diabetes. 1062 60

Blood glucose concentrations are unaffected by exercise despite very high rates of glucose flux. The plasma ionised calcium levels are even more tightly controlled after meals and during lactation. This implies 'integral control'. However, pairs of integral counterregulatory controllers (e.g. insulin and glucagon, or calcitonin and parathyroid hormone) cannot operate on the same controlled variable, unless there is some form of mutual inhibition. Flip-flop functional coupling between pancreatic alpha- and beta-cells via gap junctions may provide such a mechanism. Secretion of a common inhibitory chromogranin by the parathyroids and the thyroidal C-cells provides another. Here we describe how the insulin:glucagon flip-flop controller can be complemented by growth hormone, despite both being integral controllers. Homeostatic conflict is prevented by somatostatin-28 secretion from both the hypothalamus and the pancreatic islets. Our synthesis of the information pertaining to the glucose homeostat that has accumulated in the literature predicts that disruption of the flip-flop mechanism by the accumulation of amyloid in the pancreatic islets in type 2 diabetes mellitus will lead to hyperglucagonaemia, hyperinsulinaemia, insulin resistance, glucose intolerance and impaired insulin responsiveness to elevated blood glucose levels. It explains syndrome X (or metabolic syndrome) as incipient type 2 diabetes in which the glucose control system, while impaired, can still maintain blood glucose at the desired level. It also explains why it is characterised by high plasma insulin levels and low plasma growth hormone levels, despite normoglycaemia, and how this leads to central obesity, dyslipidaemia and cardiovascular disease in both syndrome X and type 2 diabetes.
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PMID:A reappraisal of the blood glucose homeostat which comprehensively explains the type 2 diabetes mellitus-syndrome X complex. 1271 5

We conducted a cross-sectional examination of the role of serum vitamin K levels as they relate to bone metabolism in elderly women with type II diabetes mellitus (DM). Eighty-five elderly women with type II DM were enrolled. Three fractions of vitamin K, phylloquinone (PK), menaquinone 4 (menatetrenone; MK 4), and menaquinone 7 (MK 7), along with undercarboxylated osteocalcin (UcOC), intact osteocalcin (IOC), urinary deoxypyridinoline (udpd), urinary type I collagen N-telopeptide (NTx), and intact parathyroid hormone (IPTH) were measured. Bone mineral density was measured in the lumbar spine (LSBMD) by dual-energy X-ray absorptiometry (DXA), and T scores or Z scores were calculated. The patients were divided into two groups by T score, under -2.5 (osteoporotic group) and over -2.5 (non-osteoporotic group). UcOC levels in osteoporotics patients were significantly higher than those in the non-osteoporotic group (3.09 +/- 3.94 vs 1.82 +/- 1.76 ng/ml, P = 0.02). The correlation between Z score and logarithmic UcOC/IOC levels in type II DM showed a negative trend ( P = 0.07) and a significantly and negatively association with logarithmic NTx ( r = -0.38; P = 0.001). In osteoporotic DM, the UcOC/IOC ratio was significantly correlated with the Z score ( r = -0.61; P << 0.05). Furthermore, logarithmic UcOC/IOC showed a negative correlation with logarithmic MK 7 ( r = -0.50; P = 0.001). In conclusion, the reduction in LSBMD in elderly women with type II DM may be associated, in part, with a defect in Gamma-glutamylcarboxylation by vitamin K.
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PMID:Impaired gamma carboxylation of osteocalcin in elderly women with type II diabetes mellitus: relationship between increase in undercarboxylated osteocalcin levels and low bone mineral density. 1510 65

Studies on skeletal involvement in patients with diabetes mellitus have generated conflicting results, largely because of the pathogenetic complexity of the condition. Several mechanisms may contribute to skeletal damage, including the increased urinary excretion coupled with the lower intestinal absorption of calcium, the inappropriate homeostatic response in terms of parathyroid hormone secretion, and also the complex alteration of vitamin D regulation. Decreased or increased insulin and IGF-1 concentrations and the effects of the accumulation of glycation endproducts on the bone tissue could also play a role. A possible genetic predisposition is also currently under investigation. Finally, the role of fat tissue in type 1 and type 2 diabetes and that of diabetic complications also deserve note. As far as bone mass is concerned, in adult patients with type 1 diabetes a moderately reduced bone mineral density has been shown in both axial and appendicular skeleton. On the contrary, patients with type 2 diabetes seem to have higher bone mineral density in respect to healthy control subjects, especially when overweight women are considered. No clear relationship between bone mass measurements and biochemical parameters of mineral metabolism has been shown in the different types of diabetes. Cohort studies recently carried out on large samples indicate that diabetic patients (with both type 1 and type 2 disease) have a higher risk for fracture, in particular for hip fracture, the most dangerous osteoporotic complication. This seems to be dependent both on qualitative and quantitative alterations of the bone, as well as on extra-skeletal factors due to the neuropathic and microangiopathic complications of the disease.
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PMID:Skeletal involvement in patients with diabetes mellitus. 1513 50


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