Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Amylin is a 37-amino-acid peptide related to CGRP and calcitonin. It is co-secreted with insulin from pancreatic beta-cells. Amylin is deficient with type 1 diabetes mellitus. To study the in vivo effects of amylin in humans, diabetic patients are an adequate model of chronic amylin deficiency. We investigated the effect of a 12 months pramlintide therapy (amylin analogue) on bone metabolism in patients with type 1 diabetes mellitus. 23 patients with type 1 diabetes mellitus (age 45.2 +/- 10.3 years, duration of diabetes mellitus 20.7 +/- 9.8 years, 13 male, 10 female) injected themselves 0.1 ml pramlintide, a human amylin analogue, four times per day for a period of 12 months. Bone mineral density measurements of the lumbar spine by dual-energy X-ray absorptiometry (DXA), and biochemical markers of bone metabolism (serum-calcium, PTH, osteocalcin, urinary pyridinium cross-links) were obtained before and one year after starting pramlintide therapy. None of the following parameters changed significantly: bone density, serum calcium, PTH, osteocalcin or pyridinium cross-links. Only osteocalcin decreased from 7.205 ng/ml to 5.825 ng/ml, but this change was not statistically significant. We conclude that a one-year pramlintide therapy does not affect bone density or bone metabolism in patients with type 1 diabetes mellitus without osteopenia (based on the markers used).
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PMID:The effect of pramlintide (amylin analogue) treatment on bone metabolism and bone density in patients with type 1 diabetes mellitus. 1049 73

Multiple studies have documented reduction in peripheral bone mass in children with insulin dependent diabetes mellitus (IDDM). In this study, the bone mineral density (BMD) of the lumbar vertebrae (L2-L4) was measured by dual photon absorptiometry in 14 female and 16 male diabetic patients of age 11 to 16 years with varying clinical duration. Twenty three children between 11 to 16 years with normal anthropometric measurements between 10th and 97th percentile and no known history of metabolic bone disease served as a control group. BMD values, weight, height, body mass index, metabolic, biochemical and growth parameters of the study group were compared with those of the control group. BMD (L2 AP 0.732 +/- 0.15 gm/cm2, L2 lateral 0.534 +/- 0.09 gm/cm2 in the study group and 0.812 +/- 0.63 gm/cm2 and 0.619 +/- 0.20 gm/cm2 in the control group) and osteocalcin (10.10 +/- 3.40 ng/ml and 23.12 +/- 2.74 ng/ml in diabetes and control respectively) levels were significantly lower in diabetic patients (p < 0.05, p < 0.01 respectively). Within the study group BMD correlated positively with age but not with the duration of the disease nor with the level of metabolic control.
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PMID:Evaluation of bone mineral density in children with diabetes mellitus. 1079 85

Insulin dependent diabetes mellitus, marked by high blood glucose levels and no insulin secretion, is associated with decreased bone mass and increased fracture rates. Analysis of bone histology suggests that osteoblast phenotype and function are influenced by diabetes. To determine if elevated extracellular glucose levels could directly influence osteoblast phenotype we treated mouse osteoblasts, MC3T3-E1 cells, with 22 mM glucose and analyzed osteoblast gene expression. Collagen I mRNA levels significantly increased while osteocalcin mRNA levels decreased 24 h after the addition of glucose. Expression of other genes, actin, osteopontin, and histone H4, was unaffected. Effects on collagen I expression were seen as early as 1 h after treatment. c-Jun, an AP-1 transcription factor involved in the regulation of osteoblast gene expression and growth, was also modulated by glucose. Specifically, an increase in c-jun expression was found at 1 h and maintained for 24 h following glucose treatment. Treatment of osteoblasts with an equal concentration of mannitol completely mimicked glucose treatment effects on collagen I and c-jun expression, demonstrating that osmotic stress rather than glucose metabolism is responsible for the effects on osteoblast gene expression and phenotype. Additional studies using staurosporine and Ro-31-8220 demonstrate that protein kinase C is required for the glucose up regulation of collagen I and c-jun. Taken together, our results demonstrate that osteoblasts respond to increasing extracellular glucose concentration through an osmotic response pathway that is dependent upon protein kinase C activity and results in upregulation of c-jun and modulation of collagen I and osteocalcin expression.
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PMID:Extracellular glucose influences osteoblast differentiation and c-Jun expression. 1096 57

Amylin (AMY) is a 37 amino acid peptide cosecreted with insulin (INS) by pancreatic beta-cells and absent in type 1 diabetes, a condition frequently associated with osteopenia. AMY binds to calcitonin receptors, lowers plasma calcium concentration, inhibits osteoclast activity, and stimulates osteoblasts. In the present study, we examined the effects of AMY replacement on bone loss in a streptozotocin (STZ)-induced rodent model type 1 diabetes. Of 50 male Wistar rats studied, 40 were made diabetic with intraperitoneal STZ (50 mg/kg; plasma glucose concentrations > 11 mM within 5 days). Ten nondiabetic control (CONT) rats received citrate buffer without STZ. Diabetic rats were divided into four groups (n = 10/group) and injected subcutaneously with rat AMY (45 mg/kg), INS (12 U/kg), both (same doses), or saline (STZ; diabetic controls) once per day. After 40 days of treatment and five 24-h periods of urine collection for deoxypyridinoline (DPD), the animals were killed, blood was sampled, and femurs were removed. The left femur was tested for mechanical resistance (three-point bending). The right femur was tested for total, diaphyseal (cortical bone), and metaphyseal (trabecular bone) bone densities using dual-energy X-ray absorptiometry (DXA). Bone was ashed to determine total bone mineral (calcium) content. None of the treatments had any significant effect on femoral length and diameter. Untreated diabetic rats (STZ; 145+/-7N) had lower bone strength than did nondiabetic CONT (164+/-38; p < 0.05). Total bone mineral density (BMD; g/cm2) was significantly lower in STZ (0. 2523+/-0.0076) than in CONT (0.2826+/-0.0055), as were metaphyseal and diaphyseal densities. Diabetic rats treated with AMY, INS, or both had bone strengths and bone densities that were indistinguishable from those in nondiabetic CONT. Changes in bone mineral content paralleled those for total BMD (T-BMD). Plasma osteocalcin (OC) concentration, a marker for osteoblastic activity, was markedly lower in untreated diabetic rats (7. 6+/-0.9 ng/ml); p < 0.05) than in nondiabetic CONT (29.8+/-1.7; p < 0.05) or than in AMY (20.1+/-0.7; p < 0.05). Urinary DPD excretion, a marker for bone resorption, was similar in untreated and AMY-treated diabetic rats (35.0+/-3.1 vs. 35.1+/-4.4 nmol/mmol creatinine), intermediate in rats treated with INS (49.9+/-2.7), and normalized in diabetic rats treated with both agents (58.8+/-8.9 vs. 63.2+/-4.5 in CONT). Thus, in our STZ rat model of diabetic osteopenia, addition of AMY improved bone indices apparently by both inhibiting resorption and stimulating bone formation.
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PMID:Amylin and bone metabolism in streptozotocin-induced diabetic rats. 1134 42

The effects of insulin dependent diabetes mellitus (IDDM) on bone metabolism are still not well defined. We evaluated total bone mineral content (TBMC) and bone mineral density (BMD) at the lumbar spine and femoral neck using dual X-ray absorptiometry in 26 IDDM children (15 M, 11 F) with a mean chronological age of 12.1+/-3.1 yr (range 7.1-14.2 yr). Duration of diabetes was 4.3+/-2.9 yr, with a mean glycosylated hemoglobin of 9.2+/-0.4%. BMD and TBMC standard deviation scores (Z-scores) were determined by comparing our results to controls matched for age, sex and pubertal status. BMD and bone formation and resorption markers were determined at the beginning of the study and after one year of follow up. Mean lumbar spine Z-score was -1.06+/-0.2, with negative values in 24 of 26 children (92.6%); 14/26 patients (53.8%) had a lumbar spine Z-score >1.0 SD below the mean. Mean lumbar spine Z-score remained unchanged after one year of follow up (-1.02+/-0.3). No significant differences were obtained in femoral neck BMD or TBMC between groups. No correlation was observed between lumbar spine BMD Z-scores and duration of IDDM or degree of diabetes control, as assessed by the mean glycosylated hemoglobin. Daily urinary calcium excretion was elevated in our patients initially and after one year of follow up; however, no correlation was obtained between lumbar spine BMD and 24 h urinary calcium excretion. Carboxy-terminal propeptide of type 1 collagen values and levels of urinary cross-linked N-telopeptides of type 1 collagen in the diabetic children were significantly lower than those of the matched controls. Osteoblastic activity as assessed by serum osteocalcin and by the carboxy-terminal propeptide of type I collagen and bone resorption as measured by cross-linked N-telopeptides of type 1 collagen did not correlate with the lumbar spine Z-scores. When IDDM patients were subdivided into males and females and into children with more than or less than 2 yr duration of diabetes since diagnosis, no differences between groups were found. These results suggest that insulin dependent diabetes in children is associated with low bone turnover resulting in a deficit in bone mass which may be manifested as osteopenia in the growing bone. This defect is already present in trabecular bone early on in the disease and seems not to be related to glycemic control.
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PMID:Decreased lumbar spine bone mass and low bone turnover in children and adolescents with insulin dependent diabetes mellitus followed longitudinally. 1151 57

Type 1 diabetic individuals are known to develop disorders of bone metabolism resulting in osteopenia. Previous studies have suggested an influence of vitamin D receptor alleles on bone metabolism and susceptibility for type 1 diabetes mellitus. The present study was initiated to investigate the distribution of vitamin D receptor alleles in Caucasian type 1 diabetic patients and their relation to bone turnover parameters. 75 patients were included and compared to 57 healthy controls. Three vitamin D receptor alleles were examined (BsmI, TaqI and FokI); serum levels of intact osteocalcin, parathyroid hormone, bone specific alkaline phosphatase, the carboxy terminal extension peptide of type I procollagen, 25-OH-vitamin D levels, HbA1c and urinary deoxypyridinoline excretion were measured. We observed a higher frequency of the TT genotype in diabetic patients, but no difference in markers of bone turnover between diabetics and non-diabetics in either sex. Bone turnover was different in men and in women without any association with vitamin D receptor genotype. No association was found between diabetes duration, age of onset or metabolic control and bone turnover parameters. In summary, our results show an association between the TT genotype and diabetes in Germans, but no difference in bone turnover markers between diabetics and non-diabetics.
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PMID:VDR gene polymorphisms are overrepresented in german patients with type 1 diabetes compared to healthy controls without effect on biochemical parameters of bone metabolism. 1217 74

Although osteoporosis is reported as a potential complication of type 1 diabetes mellitus (DM), the effects of type 2 DM on bone mass are conflicting. Most of the studies conducted in recent years reveal that bone mineral density (BMD) values of type 2 DM patients are not decreased and even increased when compared with healthy control groups. In this study we evaluated bone turnover in 57 postmenopausal type 2 DM patients utilizing biochemical markers for bone formation and resorption, and BMD measurements. We found that BMD values in diabetic patients (0.91 +/- 0.11 g/cm(2) for lumbar region, 0.89 +/- 0.14 g/cm(2) for hip region) were higher than healthy postmenopausal control group (0.81 +/- 0.12 g/cm(2) for lumbar region, 0.76 +/- 0.10 g/cm(2) for hip region). Serum alkaline phosphatase values were similar to the control group, whereas serum osteocalcin and N-telopeptide/creatinine (NTx/Cr) values were significantly lower than the control group (osteocalcin: 8.82 +/- 4.03 ng/ml, NTx/Cr: 122.70 +/- 81.76 nMBCE/mMCr) in diabetic patients (osteocalcin: 4.44 +/- 3.53 ng/ml, NTx/Cr: 42.24 +/- 29.97 nMBCE/mMCr). Also a significant correlation was observed between body mass index and BMD values. Our findings suggested that the bone turnover rate is remarkably lower in type 2 DM patients compared to healthy postmenopausal patients.
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PMID:Evaluation of bone turnover in postmenopausal patients with type 2 diabetes mellitus using biochemical markers and bone mineral density measurements. 1272 15

In this study, we aimed to compare bone calcium system changes from children with diabetic ketoacidosis or acute metabolic acidosis due to dehydration to find out the relative contribution of metabolic acidosis and diabetes-related factors on expected negative calcium balance. We studied a set of non-invasive parameters of bone remodeling in 16 children with diabetic ketoacidosis due to new onset type 1 diabetes and 25 children with acute metabolic acidosis due to dehydration complicating acute gastroenteritis before and after the correction of acidosis. The two groups of subjects were matched for age, sex, pubertal status, and degree of metabolic acidosis and dehydration. A group of 18 age and sex-matched healthy children served as the control group. Plasma ionized calcium levels were increased in both groups, significantly more so in diabetic ketoacidosis. While osteoblastic markers, osteocalcin and alkaline phosphatase, were depressed to a comparable degree in both groups, urinary calcium/creatinine ratio and hydroxyproline excretion were significantly greater in diabetic ketoacidosis. No significant changes in calcitrophic hormone (intact PTH, calcitonin, 25-hydroxy vitamin D3) levels were observed. All study parameters except for serum phosphate levels behaved in parallel in both clinical conditions, and abnormalities disappeared with the correction of acidosis except for IGF-1, which remained low in diabetic subjects. In conclusion, our results suggest that, in diabetic ketoacidosis, the observed severe negative calcium balance occurred through diminished bone formation mediated by metabolic acidosis per se and increased bone mineral dissolution and bone resorption because of severe insulin deficiency and secondarily via metabolic acidosis. Observed changes appear to be independent of calcitrophic hormones.
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PMID:Bone calcium changes during diabetic ketoacidosis: a comparison with lactic acidosis due to volume depletion. 1586 25

Decreased bone mass, osteoporosis, and increased fracture rates are common skeletal complications in patients with insulin-dependent diabetes mellitus (IDDM; type I diabetes). IDDM develops from little or no insulin production and is marked by elevated blood glucose levels and weight loss. In this study we use a streptozotocin-induced diabetic mouse model to examine the effect of type I diabetes on bone. Histology and microcomputed tomography demonstrate that adult diabetic mice, exhibiting increased plasma glucose and osmolality, have decreased trabecular bone mineral content compared with controls. Bone resorption could not completely account for this effect, because resorption markers (tartrate-resistant acid phosphatase 5b, urinary deoxypyridinoline excretion, and tartrate-resistant acid phosphatase 5 mRNA) are unchanged or reduced at 2 and/or 4 wk after diabetes induction. However, osteocalcin mRNA (a marker of late-stage osteoblast differentiation) and dynamic parameters of bone formation were decreased in diabetic tibias, whereas osteoblast number and runx2 and alkaline phosphatase mRNA levels did not differ. These findings suggest that the final stages of osteoblast maturation and function are suppressed. We also propose a second mechanism contributing to diabetic bone loss: increased marrow adiposity. This is supported by increased expression of adipocyte markers [peroxisome proliferator-activated receptor gamma2, resistin, and adipocyte fatty acid binding protein (alphaP2)] and the appearance of lipid-dense adipocytes in diabetic tibias. In contrast to bone marrow, adipose stores at other sites are depleted in diabetic mice, as indicated by decreased body, liver, and peripheral adipose tissue weights. These findings suggest that IDDM contributes to bone loss through changes in marrow composition resulting in decreased mature osteoblasts and increased adipose accumulation.
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PMID:Increased bone adiposity and peroxisomal proliferator-activated receptor-gamma2 expression in type I diabetic mice. 1590 21

The effects of type 1 diabetes on de novo bone formation during tibial distraction osteogenesis (DO) and on intact trabecular and cortical bone were studied using nonobese diabetic (NOD) mice and comparably aged nondiabetic NOD mice. Diabetic mice received treatment with insulin, vehicle, or no treatment during a 14-day DO procedure. Distracted tibiae were analyzed radiographically, histologically, and by microcomputed tomography (microCT). Contralateral tibiae were analyzed using microCT. Serum levels of insulin, osteocalcin, and cross-linked C-telopeptide of type I collagen were measured. Total new bone in the DO gap was reduced histologically (P < or = 0.001) and radiographically (P < or = 0.05) in diabetic mice compared with nondiabetic mice but preserved by insulin treatment. Serum osteocalcin concentrations were also reduced in diabetic mice (P < or = 0.001) and normalized with insulin treatment. Evaluation of the contralateral tibiae by microCT and mechanical testing demonstrated reductions in trabecular bone volume and thickness, cortical thickness, cortical strength, and an increase in endosteal perimeter in diabetic animals, which were prevented by insulin treatment. These studies demonstrate that bone formation during DO is impaired in a model of type 1 diabetes and preserved by systemic insulin administration.
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PMID:Bone formation is impaired in a model of type 1 diabetes. 1618 88


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