Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Besides the classical cardiovascular diseases, high levels of blood glucose directly interfere with cardiomyocytes. The mechanisms responsible for this have not yet been explored in detail. This study aims to determine if hyperglycaemia has any impact on prominent signalling molecules and on the contractile function of cardiomyocytes. Freshly isolated cardiomyocytes from adult rats were treated with various concentrations of glucose. Formed free radicals were measured by DCF-fluorescence. TGFbeta expression and p38 MAP-kinase (MAPK) activation were measured by Western blotting. The contractile efficiency was determined by measurement of the maximal amount of cell shortening. Glucose (30 mM) caused an increase in formation of radicals, phosphorylation of p38 MAPK, and TGFbeta expression. Under conditions of low viscosity (1 cp), contractile responses to hyperglycaemia (15 mM) were not altered in contrast to control. However, enhancement of viscosity (400 cp) effected a limitation of contractile function. The responsiveness to beta-adrenoceptor stimulation did not change. Neither inhibition of p38 MAPK with SB 202190 (1 microM) nor inhibition of reactive oxygen species with vitamin C did alter these measured functional parameters. Diabetes mellitus directly influences the activation degree of prominent signalling molecules and the contractile function of adult ventricular cardiomyocytes, which results in facilitating in the development of diabetic cardiomyopathy.
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PMID:No correlation between the p38 MAPK pathway and the contractile dysfunction in diabetic cardiomyocytes: hyperglycaemia-induced signalling and contractile function. 1604 1

ACE inhibition protects kidney function, but ACE insertion/deletion (I/D) polymorphism affects renal prognosis in type 1 diabetic patients. ACE genotype may influence the renal benefits of ACE inhibition. We studied the impact of ACE I/D polymorphism on the renal hemodynamic changes induced by ACE inhibition in type 1 diabetes. We studied renal hemodynamics (glomerular filtration rate [GFR], effective renal plasma flow [ERPF], filtration fraction [GFR/ERPF], mean arterial pressure [MAP], and total renal resistances [MAP/ERPF]) repeatedly during normoglycemia and then hyperglycemia in 12 normotensive, normoalbuminuric type 1 diabetes and the II genotype (associated with nephroprotection) versus 22 age- and sex-matched subjects with the ACE D allele after three randomly allocated 2- to 6-week periods on placebo, 1.25 mg/day ramipril, and 5 mg/day ramipril in a double-blind, cross-over study. During normoglycemia, the hemodynamic changes induced by ramipril were similar in both genotypes. During hyperglycemia, the changes induced by ramipril were accentuated in the II genotype group and attenuated dose dependently in the D allele group (treatment-genotype interaction P values for ERPF, 0.018; MAP, 0.018; and total renal resistances, 0.055). These results provide a basis to different renal responses to ACE inhibition according to ACE genotype in type 1 diabetes.
Diabetes 2005 Oct
PMID:Modulation of the renal response to ACE inhibition by ACE insertion/deletion polymorphism during hyperglycemia in normotensive, normoalbuminuric type 1 diabetic patients. 1618 99

Increased oxidative stress and reduced nitric oxide (NO) bioactivity are key features of diabetes mellitus that eventually result in cardiovascular abnormalities. We assessed whether N-acetylcysteine (NAC), an antioxidant and glutathione precursor, could prevent the hyperglycaemia induced increase in oxidative stress, restore NO availability and prevent depression of arterial blood pressure and heart rate in vivo in experimental diabetes. Control (C) and streptozotocin-induced diabetic (D) rats were treated or not treated with NAC in drinking water for 8 weeks, initiated 1 week after induction of diabetes. At termination, plasma levels of free 15-F2t-isoprostane, a specific marker of oxygen free radical induced lipid peroxidation, was increased while the plasma total antioxidant concentration was decreased in untreated diabetic rats as compared to control rats (P<0.05). This was accompanied by a significant reduction of plasma levels of nitrate and nitrite, stable metabolites of NO, (P<0.05, D vs. C) and a reduced endothelial NO synthase protein expression in the heart and in aortic and mesenteric artery tissues. Systolic, diastolic and mean arterial blood pressures (SBP, DBP and MAP) and heart rate (HR) were reduced in diabetic rats (P<0.05 vs. C) and NAC normalised the changes that occurred in the diabetic rats. The protective effects may be attributable to restoration of NO bioavailability in the circulation.
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PMID:Antioxidant N-acetylcysteine restores systemic nitric oxide availability and corrects depressions in arterial blood pressure and heart rate in diabetic rats. 1639 Aug 27

Following implantation, the maintenance of the pregnancy is dependent on a multitude of endocrinological events that will eventually aid in the successful growth and development of the fetus. Although the great majority of pregnant women have no pre-existing endocrine abnormalities, a small number of women can have certain endocrine alterations that could potentially lead to recurrent pregnancy losses. It is estimated that approximately 8 to 12% of all pregnancy losses are the result of endocrine factors. During the preimplantation period, the uterus undergoes important developmental changes stimulated by estrogen, and more importantly, progesterone. Progesterone is essential for the successful implantation and maintenance of pregnancy. Therefore, disorders related to inadequate progesterone secretion by the corpus luteum are likely to affect the outcome of the pregnancy. Luteal phase deficiency, hyperprolactinemia, and polycystic ovarian syndrome are some examples. Several other endocrinological abnormalities such as thyroid disease, hypoparathyroidism, uncontrolled diabetes, and decreased ovarian reserve have been implicated as etiologic factors for recurrent pregnancy loss.
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PMID:Endocrinology of recurrent pregnancy loss. 1641 76

Tissue factor (TF), formerly known as thromboplastin, is the key initiator of the coagulation cascade; it binds factor VIIa resulting in activation of factor IX and factor X, ultimately leading to fibrin formation. TF expression and activity can be induced in endothelial cells, vascular smooth muscle cells, and monocytes by various stimuli such as cytokines, growth factors, and biogenic amines. These mediators act through diverse signal transduction mechanisms including MAP kinases, PI3-kinase, and protein kinase C. Cellular TF is present in three pools as surface, encrypted, and intracellular protein. TF can also be detected in the bloodstream, referred to as circulating or blood-borne TF. Elevated levels of TF are observed in patients with cardiovascular risk factors such as hypertension, diabetes, dyslipidemia, and smoking as well as in those with acute coronary syndromes. TF may indeed be involved in the pathogenesis of atherosclerosis by promoting thrombus formation; in addition, it can induce migration and proliferation of vascular smooth muscle cells. As a consequence, therapeutic strategies have been developed to specifically interfere with the action of TF such as antibodies against TF, site-inactivated factor VIIa, or recombinant TF pathway inhibitor. Inhibition of TF action appears to be an attractive target for the treatment of cardiovascular diseases.
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PMID:Tissue factor in cardiovascular diseases: molecular mechanisms and clinical implications. 1646 45

Diabetes and ageing induce reduction and dysfunction of vascular progenitor cells. Advanced glycation endproducts (AGEs) accumulate in diabetes and ageing. We investigated the influence of AGEs on function of CD34 progenitor cells. CD34 cells were co-cultured with HUVECs in a three-dimensional spheroid assay. Sprout length growth and incorporation of CD34 cells into the sprouts were analyzed under 2, 20 or 200 microg/ml AGEs. AGE-receptor expression, MAP-kinase signal transduction and apoptosis were analyzed using PCR, Western blotting and flow cytometry. In the spheroid assay, AGEs concentration-dependently cause a reduction of sprout length growth by 6+/-6 to 32+/-6% and an attenuation of progenitor cells incorporation into the sprouting endothelium by up to 43+/-6%. This functional impairment is accompanied by activation of CD34 cell proliferation at lower concentrations (2 or 20 microg/ml) and by apoptosis activation under 200 microg/ml AGEs. The mRNA expression of the receptors for AGEs and the AGEs-induced activation of p38 and p44/42 MAP-kinases are demonstrable in CD34 cells. This AGEs-mediated impairment of progenitor cell function identifies a new pathophysiological mechanism of disturbed vascular adaptation in diabetes or ageing and suggests that lowering AGEs in recipients of progenitor cell therapy might be beneficial for the success of this therapy.
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PMID:Depression of progenitor cell function by advanced glycation endproducts (AGEs): potential relevance for impaired angiogenesis in advanced age and diabetes. 1651 51

Acrolein, which is a highly reactive alpha,beta-unsaturated aldehyde generated by lipid peroxidation, can affect cells and tissues and cause various disorders. Increased levels of unsaturated aldehydes play an important role in the pathogenesis of a number of human diseases such as Alzheimer's disease, atherosclerosis and diabetes. Acrolein is a highly ubiquitous toxic environmental pollutant. Because of human exposure, there is a need for investigating the mechanisms involved in acrolein toxicity at the cellular and molecular levels. Acrolein can induce cell death by apoptosis, although the mechanisms are not entirely clear. The present study investigates whether mitogen-activated protein kinases (MAPKs) play a role in activation of apoptosis by acrolein. Our findings show that acrolein-mediated apoptosis is in fact MAPK-dependent in Chinese hamster ovary cells. The MAP family kinases, including ERK and p38 kinase, and the transcription factor c-Jun were all activated by phosphorylation after 1 h exposure to acrolein. Phosphorylation of ERK and p38 kinases and their blockade by an ERK inhibitor, U0126, or a p38 inhibitor, SB203580, respectively, suggested that activation of apoptosis by acrolein is ERK- and p38-dependent. Thus, blockade of ERK and p38 inhibited chromatin condensation, caspase-7 and -9 activation as well as ICAD cleavage induced by acrolein. JNK and AKT kinases seem to be implicated in survival pathways against acrolein insult, since their respective inhibitors, SP600125 and LY294002/Wortmannin switched the mode of cell death from apoptosis to total necrosis. Finally, acrolein induced phosphorylation of the pro-apoptotic factor p53 which is responsible for transcription of pro-apoptotic factors such as Bax and Fas ligand. These results provide new information demonstrating the implication of MAPKs and AKT in acrolein-induced apoptosis, and this information may be useful for understanding the pathogenesis of a number of tissue diseases and environmental toxicity in response to acrolein.
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PMID:P38 and ERK mitogen-activated protein kinases mediate acrolein-induced apoptosis in Chinese hamster ovary cells. 1719 91

The combination of pulse-chase experiments with high-performance liquid chromatography and continuous flow scintillation detection was used successfully to determine the effects of chronic diabetes on neurosteroid production in the adult rat spinal cord. The long-term diabetes was induced by treatment of adult rats with streptozotocin. In the first part, the review provides an extensive description of the HPLC combined with continuous flow scintillation detection method, its advantages and appropriateness for the question investigated. Afterwards, the paper shows that progesterone formation is up-regulated in the spinal cord of diabetic rats while the biosynthesis of tetrahydroprogesterone decreased. The down-regulation of tetrahydroprogesterone appeared as a mechanism facilitating progesterone accumulation in the spinal cord of streptozotocin-treated rats. Progesterone is well known to be a potent neuroprotective steroid. Enhancement of its biosynthesis may be an endogenous mechanism triggered by neural cells in the spinal tissue to cope with degenerative effects provoked by chronic diabetes. Since steroid metabolism in the spinal cord is pivotal for the modulation of several neurobiological processes including sensorimotor activities, the data analyzed herein may constitute useful information for the development of efficient strategies against deleterious effects of diabetes on the nervous system.
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PMID:Assessment of neuroactive steroid formation in diabetic rat spinal cord using high-performance liquid chromatography and continuous flow scintillation detection. 1764 34

MAP Kinase Phosphatase-1 (MKP-1) is a dual specific phosphatase selective for MAP kinases, and was believed to implicate in the development of cardiac hypertrophy. However, whether MKP-1 is involved in the pathogenesis of diabetic cardiomyopathy is still unknown. We employed streptozotocin (STZ)-induced diabetic Sprague-Dawley rats to study the alteration of the MKP-1 expressions in the left ventricular myocardium in diabetic and normal groups by immunohistochemistry and real-time quantitative reverse transcription-polymerase chain reaction. The weight, blood sugar and urine sugar were measured before and after model induction in both control and diabetic groups. Changes of heart ultrastructure were analyzed by using transmission electron microscopy. The data of weight, blood sugar and urine sugar indicated no significant difference between the two groups before animal model induction. Eight weeks after the induction of diabetes, the differences between the control and the diabetic groups in weight, blood sugar and urine sugar were significant ( P<0.01). When compared with control, diabetic myocardium ultrastructural changes included myofibrillar disarrangements, mitochondria disruption, and increase in nuclear membrane invaginations. A significant decrease of MKP-1 expression was observed in the diabetic rats' myocardium ( P<0.01). Our study provides experimental evidences that hyperglycemia could damage myocardial ultrastructure. Moreover, we provided first evidence that down-regulation of cardioprotective peptide MKP-1, the MAPK pathway negative regulator, in myocardium of streptozotocin-induced diabetic rats, which may contribute to the deterioration of cardiac function and lead to diabetic cardiomyopathy.
Exp Clin Endocrinol Diabetes 2007 Jul
PMID:Expression changes of mitogen-activated protein kinase phosphatase-1 (MKP-1) in myocardium of streptozotocin-induced diabetic rats. 1764 44

Proinsulin connecting peptide (C-peptide) has been initially regarded as deprived of biological functions other than correct scaffolding of insulin. This was caused by the lack of evident effect of C-peptide administration to healthy subjects or animals. At present, in view of numerous studies concerning its structure, membrane binding and biological functions, C-peptide seems to constitute a crucial role in the pathogenesis of complications in diabetes mellitus type 1 (DM1). Patients who maintain high remnant insulin secretion (and therefore also of C-peptide) develop complications such as nephropathy, neuropathy and later microangiopathy with a milder clinical course. In this article we have covered molecular and cellular aspects of C-peptide functioning, such as: activation of protein kinase C, Na+,K+- ATP-ase, nitric oxide synthase, MAP and ERK 1/2 kinases, improvement of nerve conduction velocity and interactions with exogenous and endogenous insulin. We also outline the clinical consequences of deficiency of this underestimated peptide along with its potential therapeutical possibilities in the primary and secondary prevention of DM1 complications.
Pediatr Endocrinol Diabetes Metab 2007
PMID:[Proinsulin C-peptide -- the bioactive peptide with a huge promise]. 1788 Aug 15


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