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)

Alterations in bone metabolism in diabetes mellitus is a topic of special interest. Bone blood flow is increased in the distal limb of diabetic patients, which is believed to increase osteoclastic activity. We measure bone mineral density using dual-photon absorptiometry in the distal lower limb, the femoral neck, and the lumbar spine in 41 IDDM patients and in 30 control persons. In the diabetic group there was a 10% reduction of bone mineral density in the femoral neck (p < 0.01) and a 12% reduction in the distal limb (p < 0.001) compared with the control group. No significant difference was found in the lumbar spine (p = 0.22). Our data yield incidence for peripheral osteopenia in IDDM-patients, independent of any systemic bone disease such as osteoporosis. A link between decreased bone mineral density and diabetic neuropathy has been observed for the femoral neck (p < 0.001), but not for the distal limb or axial skeleton. Whether there is a common aetiological link or a casual connection between diabetic neuropathy and bone mineral density has still to be determined.
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PMID:Peripheral osteopenia in adult patients with insulin-dependent diabetes mellitus. 884 77

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

Localized lesions at the foot skeleton are a serious and well recognized complication of diabetes mellitus which may impair the clinical outcome of the patients remarkably. In contrast, the presence of a generalized bone disease or osteoporosis related to diabetes mellitus is less acknowledged and its clinical relevance is less obvious. This paper is a clinically focused review of the literature on osteoporosis related to diabetes mellitus. Due to the different pathogenesis of diabetes mellitus type 1 and type 2 it is not surprising that there is no uniform entity of diabetic osteopathy. The majority of clinical studies in subjects with diabetes mellitus type 1 showed a moderately decreased bone mass at the forearm, while bone mass at the femur or lumbar spine was either decreased or not different from non-diabetic controls. In patients with diabetes mellitus type 2 the risk of osteopenia is not as clear as in type 1 diabetes. Bone mineral density at the forearm in patients with type 2 diabetes mellitus was decreased, unchanged or even increased in comparison to controls, while bone mineral density at the vertebrae or femoral neck was either not significantly different or increased, but rarely decreased. The underlying mechanisms triggering changes in bone mass in patients with diabetes mellitus type 1 and type 2 are not well known. In most studies there was no consistent relationship between the metabolic control of diabetes and bone mineral density. Biochemical parameters of the calcium and bone metabolism showed no clear relationship to the bone mineral density measurements. From few bone histology studies in humans and experimental studies there is evidence that a decreased bone formation is one major mechanism leading to reduced bone mass in diabetics. Microangiopathy at the bone tissue was also discussed as a possible reason for diabetic osteopenia. It was shown that insulin and insulin like growth factors (IGF-1, IGF-2) have an influence on bone metabolism itself and other growth factors, cytokines and hormones may determine changes in diabetic bone metabolism. Recent findings suggest that leptin is involved in the regulation of osteoblast function and bone mass, which is of special interest in diabetes mellitus type 2. The clinical relevance of osteoporosis or osteopenia is determined by the increased risk for insufficiency fractures. Few studies found an increased fracture risk, especially in older women with type 1 diabetes mellitus, while others did not show an increased risk for fractures or even found a decreased rate of fractures in women with diabetes mellitus type 2. There is a need for further longitudinal studies, including the incidence and risk factors for osteoporotic fractures. In clinical routine the extent of diagnostic and therapeutic activities in patients with type 1 or type 2 diabetes mellitus in respect to generalized bone disease or diabetic osteopenia should be based on individual conditions and risk profile for osteoporosis.
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PMID:Diabetes mellitus a risk for osteoporosis? 1146 May 94

It is remarkable that phytoplankton and zooplankton have been producing vitamin D for more than 500 million years. The role of vitamin D in lower non-vertebrate life forms is not well understood. However, it is critically important that most vertebrates obtain an adequate source of vitamin D, either from exposure to sunlight or from their diet, in order to develop and maintain a healthy mineralized skeleton. Vitamin D deficiency is an unrecognized epidemic in most adults who are not exposed to adequate sunlight. This can precipitate and exacerbate osteoporosis and cause the painful bone disease osteomalacia. Once vitamin D is absorbed from the diet or made in the skin by the action of sunlight, it is metabolized in the liver to 25-hydroxyvitamin D [25(OH)D] and then in the kidney to 1,25-dihydroxyvitamin D [1,25(OH)2D]. 1,25(OH)2D interacts with its nuclear receptor (VDR) in the intestine and bone in order to maintain calcium homeostasis. The VDR is also present in a wide variety of other tissues. 1,25(OH)2D interacts with these receptors to have a multitude of important physiological effects. In addition, it is now recognized that many tissues, including colon, breast and prostate, have the enzymatic machinery to produce 1,25(OH)2D. The insights into the new biological functions of 1,25(OH)2D in regulating cell growth, modulating the immune system and modulating the renin-angiotensin system provides an explanation for why diminished sun exposure at higher latitudes is associated with increased risk of dying of many common cancers, developing type 1 diabetes and multiple sclerosis, and having a higher incidence of hypertension. Another calciotropic hormone that is also produced in the skin, parathyroid hormone-related peptide, is also a potent inhibitor of squamous cell proliferation. The use of agonists and antagonists for PTHrP has important clinical applications for the prevention and treatment of skin diseases and disorders of hair growth.
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PMID:Evolution and function of vitamin D. 1289 11

Most humans depend on sun exposure to satisfy their requirements for vitamin D. Solar ultraviolet B photons are absorbed by 7-dehydrocholesterol in the skin, leading to its transformation to previtamin D3, which is rapidly converted to vitamin D3. Season, latitude, time of day, skin pigmentation, aging, sunscreen use, and glass all influence the cutaneous production of vitamin D3. Once formed, vitamin D3 is metabolized in the liver to 25-hydroxyvitamin D3 and then in the kidney to its biologically active form, 1,25-dihydroxyvitamin D3. Vitamin D deficiency is an unrecognized epidemic among both children and adults in the United States. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risks of deadly cancers, cardiovascular disease, multiple sclerosis, rheumatoid arthritis, and type 1 diabetes mellitus. Maintaining blood concentrations of 25-hydroxyvitamin D above 80 nmol/L (approximately 30 ng/mL) not only is important for maximizing intestinal calcium absorption but also may be important for providing the extrarenal 1alpha-hydroxylase that is present in most tissues to produce 1,25-dihydroxyvitamin D3. Although chronic excessive exposure to sunlight increases the risk of nonmelanoma skin cancer, the avoidance of all direct sun exposure increases the risk of vitamin D deficiency, which can have serious consequences. Monitoring serum 25-hydroxyvitamin D concentrations yearly should help reveal vitamin D deficiencies. Sensible sun exposure (usually 5-10 min of exposure of the arms and legs or the hands, arms, and face, 2 or 3 times per week) and increased dietary and supplemental vitamin D intakes are reasonable approaches to guarantee vitamin D sufficiency.
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PMID:Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. 1558 88

Diabetic osteoporosis is increasingly recognized as a significant comorbidity of type 1 diabetes mellitus. In contrast, type 2 diabetes mellitus is more commonly associated with modest increases in bone mineral density for age. Despite this dichotomy, clinical, in vivo, and in vitro data uniformly support the concept that new bone formation as well as bone microarchitectural integrity are altered in the diabetic state, leading to an increased risk for fragility fracture and inadequate bone regeneration following injury. In this review, we examine the contribution that insulin, as a potential anabolic agent in bone, may make to the pathophysiology of diabetic bone disease. Specifically, we have assimilated human and animal data examining the effects of endogenous insulin production, exogenous insulin administration, insulin sensitivity, and insulin signaling on bone. In so doing, we present evidence that insulin, acting as an anabolic agent in bone, can preserve and increase bone density and bone strength, presumably through direct and/or indirect effects on bone formation.
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PMID:Is insulin an anabolic agent in bone? Dissecting the diabetic bone for clues. 1621 65

During the past decade, major advances have been made in vitamin D research that transcend the simple concept that vitamin D is Important for the prevention of rickets in children and has little physiologic relevance for adults. Inadequate vitamin D, in addition to causing rickets, prevents children from attaining their genetically programmed peak bone mass, contributes to and exacerbates osteoporosis in adults, and causes the often painful bone disease osteomalacia. Adequate vitamin D is also important for proper muscle functioning, and controversial evidence suggests it may help prevent type 1 diabetes mellitus, hypertension, and many common cancers. Vitamin D inadequacy has been reported in approximately 36% of otherwise healthy young adults and up to 57% of general medicine inpatients in the United States and in even higher percentages in Europe. Recent epidemiological data document the high prevalence of vitamin D inadequacy among elderly patients and especially among patients with osteoporosis. Factors such as low sunlight exposure, age-related decreases in cutaneous synthesis, and diets low in vitamin D contribute to the high prevalence of vitamin D inadequacy. Vitamin D production from cutaneous synthesis or intake from the few vitamin D-rich or enriched foods typically occurs only intermittently. Supplemental doses of vitamin D and sensible sun exposure could prevent deficiency in most of the general population. The purposes of this article are to examine the prevalence of vitamin D inadequacy and to review the potential implications for skeletal and extraskeletal health.
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PMID:High prevalence of vitamin D inadequacy and implications for health. 1652 31

The aim of the study was to assess skeletal status in diabetic and nondiabetic subjects with end-stage renal disease (ESRD). One hundred twenty-three patients with ESRD (57 patients with diabetes: 9 type 1 and 48 type 2) and 66 nondiabetic patients were evaluated. Control group comprised 1541 subjects (614 males and 927 females). Diabetes and/or renal insufficiency was the only reason of bone disease and, in control group, no factors known to influence bone metabolism (chronic diseases or prolonged medications) were noted. Skeletal status was evaluated by quantitative ultrasound measurements at the hand phalanges using DBM 1200 (IGEA, Carpi, Italy), which measures amplitude-dependent speed of sound (Ad-SoS [m/s]). Because of some differences in mean age in subgroups of patients and controls, comparisons were performed using values of Z-score. In all diabetic patients, Z-score was significantly higher compared with nondiabetics (p < 0.05). In all type 1 diabetes patients, Z-score was significantly lower than in all nondiabetic patients (p < 0.05) and in patients with type 2 diabetes (p < 0.001). Z-score was also significantly lower in type 2 diabetics than in nondiabetic females (p < 0.00001) but did not differ in males. Comparisons between Z-scores in controls and patients showed that Z-score in nondiabetic females was significantly lower than in female controls (p < 0.000001), and in nondiabetic males--diabetic type 2 males as well as females--Z-score did not differ vs. results in adequate control group. Z-score was significantly lower in patients with diabetes type 1 vs. all controls (p < 0.001). Correlation analysis showed in all nondiabetic patients that Z-score was negatively affected by duration time of dialysis (r = -0.37, p < 0.01) and parathyroid hormone (PTH) serum level (r = -0.35, p < 0.01). In patients with type 1 diabetes, only PTH influenced significantly Z-score (r = -0.76, p < 0.05) and, in patients with type 2 diabetes, no significant correlations were obtained. Subjects with type 1 diabetes seemed to be sensitive for skeletal disturbances in a course of renal insufficiency, whereas subjects with type 2 diabetes did not show such skeletal pathology as shown by ultrasound measurements at hand phalanges.
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PMID:Quantitative ultrasound measurements in diabetic and nondiabetic patients with end-stage renal disease. 1741 82

Type 1 diabetes mellitus is associated with a number of disorders of skeletal health, conditions that rely, in part, on dynamic bone formation. A mouse model of distraction osteogenesis was used to study the consequences of streptozotocin-induced diabetes and insulin treatment on bone formation and osteoblastogenesis. In diabetic mice compared with control mice, new bone formation was decreased, and adipogenesis was increased in and around, respectively, the distraction gaps. Although insulin treatment restored bone formation to levels observed in nondiabetic control mice, it failed to significantly decrease adipogenesis. Molecular events altered during de novo bone formation in untreated type 1 diabetes mellitus, yet restored with insulin treatment were examined so as to clarify specific osteogenic genes that may contribute to diabetic bone disease. RNA from distraction gaps was analyzed by gene microarray and quantitative RT-PCR for osteogenic genes of interest. Runt-related transcription factor 2 (RUNX2), and several RUNX2 target genes, including matrix metalloproteinase-9, Akp2, integrin binding sialoprotein, Dmp1, Col1a2, Phex, Vdr, osteocalcin, and osterix, were all significantly down-regulated in the insulin-deficient, hyperglycemic diabetic animals; however, insulin treatment of diabetic animals significantly restored their expression. Expression of bone morphogenic protein-2, transcriptional coactivator with PDZ-binding motif, and TWIST2, all important regulators of RUNX2, were not impacted by the diabetic condition, suggesting that the defect in osteogenesis resides at the level of RUNX2 expression and its activity. Together, these data demonstrate that insulin and/or glycemic status can regulate osteogenesis in vivo, and systemic insulin therapy can, in large part, rescue the diabetic bone phenotype at the tissue and molecular level.
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PMID:Runt-related transcription factor 2 (RUNX2) and RUNX2-related osteogenic genes are down-regulated throughout osteogenesis in type 1 diabetes mellitus. 1816 13

Diabetes mellitus induces alterations in bone and mineral metabolism. Diabetic bone disorder causes an increase in bone fractures, delays healing of fractures, and affects the quality of life. There are few optimal therapies for these disorders and the mechanisms responsible for their complications have not been clearly identified. Bone histology studies in humans and animals have demonstrated that decreased bone formation is a critical mechanism of bone mass reduction in diabetes. A major hypothesis about the mechanisms of diabetic complications is a diabetes-induced increase in oxidative stress, because reactive oxygen species (ROS) are increased under diabetic conditions and are known to induce cellular dysfunction in a wide variety of cell types. Oxidative stress is induced by a variety of mechanisms including formation of increased advanced glycation end-products (AGEs), increased polyol pathway flux, activation of protein kinase C isoforms, glucose autoxidation, and mitochondrial overproduction of superoxide under diabetic conditions. Other circulating factors that are elevated in diabetes, such as free fatty acids and leptin, also contribute to increased ROS generation. It is now widely accepted that ROS can cause severe damage to DNA, proteins, and lipids. Concerning bone metabolism, in vitro studies have shown that oxidative stress inhibits osteoblastic differentiation and induces osteoblast insults and apoptosis. Moreover, we have demonstrated that both streptozotocin-induced diabetic mice, an animal model of type 1 diabetes, and spontaneously diabetic Torii (SDT) rats, an animal model of type 2 diabetes, have low-turnover osteopenia associated with increased oxidative stress and that markers of oxidative stress are inversely associated with the histomorphometric parameters of bone formation. Growing evidence suggests that the increase in oxidative stress may at least partly contribute to the development of diabetic osteopenia. This review focuses on the impact of diabetes-induced oxidative stress in the development of diabetic bone disorder.
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PMID:Role of oxidative stress in diabetic bone disorder. 1923 2


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