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)

A significant increase in the number of old people in the populations of developed countries was followed by an increase in morbidity and mortality resulting from main age-related diseases -- cardiovascular, cancer, neurodegenerative, diabetes mellitus, decrease in resistance to infections. Obviously, the development of the means of prevention of the premature aging of humans is crucial for the realization of this program. However, data available on such kind of means are rather scarce, contradictory and are often not reliable from the points of view of the adequacy of the experiments to current scientific requirements as well as the interpretation of the results and safety. Data available on the increase in life span and the adverse effects of the following geroprotectors were critically analyzed: antioxidants, chelate agents and lathyrogens, succinate, adaptogens and herbs, neurotropic drugs, inhibitors of monoamine oxidase, glucocorticoids, dehydroepiandrosterone, sex and growth hormones, melatonin, pineal peptide preparations, protein inhibitors, antidiabetic biguanides, thymic hormones and peptides, immunomodulators, enteroadsorbents, lypofuscin inhibitors, as well as calorie intake restriction and special diets. Most of the available results were insufficient and could not provide convincing evidence for the life span extension and the safety of the suggested geroprotectors. Drugs and means prolonging the life span could be subdivided into three groups: (a) geroprotectors prolonging the life span equally in all the members of the population: these postponed the beginning of the population's aging; (b) geroprotectors decreasing the mortality rate in a long-lived subpopulation, which raised their maximal life span: these slowed down the population's aging rate; (c) geroprotectors increasing the survival rate in a short-lived subpopulation without changes in the maximal life span: in this case, the aging rate increased. There was a high positive correlation between the type of geroprotector-induced aging delay and the pattern of tumour development in the same population of animals. The first type of geroprotectors did not influence the incidence of tumour but increased tumour latency. The second type of geroprotectors was effective both in the inhibition of spontaneous carcinogenesis and the increase in tumour latency. Certain drugs of the third type raised tumour incidence in the exposed populations. According to the multistage model, geroprotectors either inhibit or accelerate the passage of carcinogen-exposed cells form one stage to another. Thus, the efficacy of geroprotectors as preventive means of cancer development will decrease with respect to the age of exposure onset. Recommendations of the available drugs and means of life span increase should be carefully reconsidered under the international scientific control.
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PMID:Life span extension and cancer risk: myths and reality. 1140 54

Aminoacetone (AA) is a threonine and glycine catabolite long known to accumulate in cri-du-chat and threoninemia syndromes and, more recently, implicated as a contributing source of methylglyoxal (MG) in diabetes mellitus. Oxidation of AA to MG, NH(4)(+), and H(2)O(2) has been reported to be catalyzed by a copper-dependent semicarbazide sensitive amine oxidase (SSAO) as well as by Cu(II) ions. We here study the mechanism of AA aerobic oxidation, in the presence and absence of iron ions, and coupled to iron release from ferritin. Aminoacetone (1-7 mM) autoxidizes in Chelex-treated phosphate buffer (pH 7.4) to yield stoichiometric amounts of MG and NH(4)(+). Superoxide radical was shown to propagate this reaction as indicated by strong inhibition of oxygen uptake by superoxide dismutase (SOD) (1-50 units/mL; up to 90%) or semicarbazide (0.5-5 mM; up to 80%) and by EPR spin trapping studies with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), which detected the formation of the DMPO-(*)OH adduct as a decomposition product from the DMPO-O(2)(*)(-) adduct. Accordingly, oxygen uptake by AA is accelerated upon addition of xanthine/xanthine oxidase, a well-known enzymatic source of O(2)(*)(-) radicals. Under Fe(II)EDTA catalysis, SOD (<50 units/mL) had little effect on the oxygen uptake curve or on the EPR spectrum of AA/DMPO, which shows intense signals of the DMPO-(*)OH adduct and of a secondary carbon-centered DMPO adduct, attributable to the AA(*) enoyl radical. In the presence of iron, simultaneous (two) electron transfer from both Fe(II) and AA to O(2), leading directly to H(2)O(2) generation followed by the Fenton reaction is thought to take place. Aminoacetone was also found to induce dose-dependent Fe(II) release from horse spleen ferritin, putatively mediated by both O(2)(*)(-) and AA(*) enoyl radicals, and the co-oxidation of added hemoglobin and myoglobin, which may be viewed as the initial step for potential further iron release. It is thus tempting to propose that AA, accumulated in the blood and other tissues of diabetics, besides being metabolized by SSAO, may release iron and undergo spontaneous and iron-catalyzed oxidation with production of reactive H(2)O(2) and O(2)(*)(-), triggering pathological responses. It is noteworthy that noninsulin-dependent diabetes has been frequently associated with iron overload and oxidative stress.
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PMID:Aerobic oxidation of aminoacetone, a threonine catabolite: iron catalysis and coupled iron release from ferritin. 1155 49

Local anesthesia is without doubt the most frequently used drug in dentistry and in medicine. In spite of records of safety set by using these drugs, there is evidence to adverse reactions ranging from 2.5%-11%. Most of the reactions originate from the autonomic system. A recent, well-planned study indicates that adverse reactions are highly correlated to the medical status of the patient: the higher the medical risk, the greater the chance to experience an adverse reaction. This study also found that adverse reactions highly correlated to the concentration of adrenalin. Another recent study found a direct relationship between adverse reactions and the level of anxiety experienced by the patient and to the dental procedure. Most of the reactions in this study occurred either immediately at injection time and within 2 hours following the injection. Since the beginning of last century, vasoconstrictors have been added to local anesthesia solutions in order to reduce toxicity and prologue activity of the LA. However, today it is commonly agreed that this addition to local anesthesia should not be administered to cardiac patients especially those suffering from refractory dysrhythmias, angina pectoris, post myocardial infarction (6 months) and uncontrolled hypertension. Other contraindications to vasoconstrictors are endocrine disorders such as hyperthyroidism, hyperfunction of the medullary adrenal (pheochromocytoma) and uncontrolled diabetes mellitus. Cross reactivity of local anesthetic solutions can occur with MAO inhibitors, non specific beta adrenergic blockers, tricyclic antidepressants, phenothiazides and cocaine abusers. Noradrenaline added to local anesthetics as a vasoconstrictor has been described as a trigger to a great increase in blood pressure and therefore has been forbidden for use in many countries. This paper describes 4 cases of severe complications following the injections of local anesthesia of which three ended in fatality.
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PMID:[Emergencies evolving from local anesthesia]. 1185 46

Various mammalian tissues contain a tissue-bound amine oxidizing enzyme distinct from mitochondrial outer membrane enzyme, monoamine oxidase (MAO, EC 1.4.3.4), termed semicarbazide-sensitive amine oxidase (SSAO, EC 1.4.3.6). An increase in SSAO activity was found in patients suffering from vascular disorders such as diabetes and diabetic complications. It has previously been shown that 2-bromoethylamine (2-BEA) is a potent, and selective suicidal inhibitor of tissue-bound SSAO. The aim of this study was to investigate the interaction of this suicidal SSAO inhibitor with the tissue-bound enzyme in guinea pig lung, kidney, stomach, and heart homogenates. The conditions necessary for this inhibitor to titrate the concentrations of this enzyme were also determined. 2-BEA appears to interact with SSAO, as reported previously for this enzyme from different sources, in a manner consistent with an irreversible, "suicide" reaction. Because of this property, 2-BEA could be used to titrate the concentrations of SSAO active centers in these tissues under the appropriate conditions employed. Although some possible non-specific binding of the inhibitor to sites other than the active center of the enzyme, metabolism of this inhibitor and/or presence of enzyme subtypes was hypothesized, the molecular characteristics of SSAO in these tissues (Km, Vmax values, enzyme efficiencies, approximate enzyme concentrations, and molecular turnover numbers) towards the substrate kynuramine (0.1 mM) at pH 7.4 and 37 degrees C have been estimated.
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PMID:Molecular characteristics of tissue-bound semicarbazide-sensitive amine oxidase (SSAO) in guinea pig tissues. 1189 3

This review discusses the current insight by which mutations in mitochondrial DNA (mtDNA) contribute to the development of particular disease states with emphasis on diabetes mellitus. Mitochondria are the power factories of the cells and produce ATP by oxidizing reducing equivalents via the respiratory chain. These reducing equivalents originate mainly from the citric acid cycle that also occurs within the mitochondria. Human mitochondria contain their own genetic material in the form of circular DNA that encodes for only a fraction of the mitochondrial components. The other mitochondrial components are nuclear encoded. Pathogenic mutations in mtDNA can affect the activity of the respiratory chain, thereby leading to the reduced generation of ATP. However, mitochondria not only produce ATP but they also regulate cytosolic concentrations of signaling molecules such as calcium and iron ions. The metabolic processes within mitochondria such as the citric acid cycle determine the concentration of metabolites that can also act as signalling molecules. Furthermore, the respiratory chain and mitochondrion-associated monoamine oxidase are major producers of reactive oxygen radicals. As a result, mutations in mtDNA can deregulate multiple processes within cells and the balance of this deregulation may contribute to the clinical phenotype.
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PMID:Mitochondrial diabetes mellitus. 1203 48

Between 20 and 35% of all dementias are vascular in origin, their etiology is due to cerebrovascular disease and the risk factors are known (e.g. hypertension, diabetes, smoking, or hyperlipidemia). Primary and secondary preventions are the basis of therapeutics. Symptomatic treatment is emerging, notably in the field of cognitive disorders. In that respect, monoamine oxidase inhibitors, and more recently acetylcholinesterase inhibitors, are in the process of being recognized as first-line treatments of established vascular dementia.
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PMID:Drugs and vascular dementia. 1271 93

Aminoacetone (AA) is a threonine and glycine metabolite overproduced and recently implicated as a contributing source of methylglyoxal (MG) in conditions of ketosis. Oxidation of AA to MG, NH4+, and H2O2 has been reported to be catalyzed by a copper-dependent semicarbazide sensitive amine oxidase (SSAO) as well as by copper- and iron ion-catalyzed reactions with oxygen. We previously demonstrated that AA-generated O2*-. and enoyl radical (AA*) induce dose-dependent Fe(II) release from horse spleen ferritin (HoSF); no reaction occurs under nitrogen. In the present study we further explored the mechanism of iron release and the effect of AA on the ferritin apoprotein. Iron chelators such as EDTA, ATP and citrate, and phosphate accelerated AA-promoted iron release from HoSF, which was faster in horse spleen isoferritins containing larger amounts of phosphate in the core. Incubation of apoferritin with AA (2.5-50 mM, after 6 h) changes the apoprotein electrophoretic behavior, suggesting a structural modification of the apoprotein by AA-generated ROS. Superoxide dismutase (SOD) was able to partially protect apoferritin from structural modification whereas catalase, ethanol, and mannitol were ineffective in protection. Incubation of apoferritin with AA (1-10 mM) produced a dose-dependent decrease in tryptophan fluorescence (13-30%, after 5 h), and a partial depletion of protein thiols (29% after 24 h). The AA promoted damage to apoferritin produced a 40% decrease in apoprotein ferroxidase activity and an 80% decrease in its iron uptake ability. The current findings of changes in ferritin and apoferritin may contribute to intracellular iron-induced oxidative stress during AA formation in ketosis and diabetes mellitus.
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PMID:Aminoacetone induces loss of ferritin ferroxidase and iron uptake activities. 1470 1

Cohort studies indicate a high prevalence of depression in patients with diabetes mellitus. Despite numerous investigations, the underlying pathophysiologies of the metabolic abnormalities are poorly understood. A possible role play the increased counter-regulatory hormone release involved in glucose homeostasis, alterations in the glucose transport function and increased inflammatory activation triggered by depression. The diagnose of "depression" in diabetic patients might be hampered by similar symptoms of both conditions as fatigue, psychomotor inhibition, reduced appetite or sexual dysfunction. In treating depressive patients with diabetes one should consider potential induction or worsening of diabetes-like metabolic alterations. Selective serotonin-reuptake-inhibitors, venlafaxin and MAO-Inhibitors constitute a beneficial choice. Atypical antipsychotics like clozapine, olanzapine, quetiapine and risperidone should be given with precaution due to potential effects on glucose homeostasis.
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PMID:[Diabetes and depression]. 1584 25

A soluble form of semicarbazide-sensitive amine oxidase (SSAO) circulating in plasma is known to increase in type 1 and 2 diabetes. This cuproenzyme generates hydrogen peroxide, ammonia, and aldehydes when oxidizing circulating biogenic or exogenous amines. Based on the angiotoxicity of these products, inhibition of SSAO has been proposed to prevent vascular complications of diabetes. However, substrates of SSAO and monoamine oxidase (MAO) have been recently evidenced to activate glucose utilisation in insulin-sensitive tissues and to exhibit antihyperglycemic actions. To determine whether amine oxidase blockade or activation could be beneficial for diabetes, we aimed at comparing the influence of prolonged treatments with semicarbazide (SSAO-inhibitor), pargyline (MAO-inhibitor), or tyramine (amine oxidase substrate) on amine oxidase activities and glycemic control in streptozotocin-induced diabetic rats. The increase in plasma SSAO was confirmed in diabetic rats, while MAO and SSAO were decreased in subcutaneous adipose tissue when compared with normoglycemic controls. Among the diabetic rats, only those receiving tyramine exhibited slightly decreased hyperglycemia and improved glucose tolerance. Adipocytes from untreated or treated diabetic rats shared similar sensitivity to insulin. However glucose uptake activation and lipolysis inhibition in response to amine oxidase substrates combined with vanadate were impaired in rats treated with amine oxidase inhibitors. Thus, amine oxidase inhibition does not improve metabolic control while prolonged administration of tyramine slightly improves glucose disposal. It is therefore concluded that amine oxidase activation by increased substrate supply elicits insulin-like actions that may be more beneficial in diabetes than SSAO inhibition formerly proposed to prevent vascular complications.
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PMID:Glucose handling in streptozotocin-induced diabetic rats is improved by tyramine but not by the amine oxidase inhibitor semicarbazide. 1620 94

Weight gain is associated with the use of many psychotropic medications, including antidepressants, mood stabilizers, antipsychotic drugs, and may have serious long term consequences: it can increase health risks, specifically from overweight (BMI = 25-29.9 kg/m2) to obesity (BMI > or =30 kg/m2), according to Body Mass Index (BMI), and the morbidity associated therewith in a substantial part of patients (hypertension, coronary heart desease, ischemic stroke, impaired glucose tolerance, diabetes mellitus, dyslipidemia, respiratory problems, osteoarthritis, cancer); according to patients, psychosocial consequences such as a sense of demoralization, physical discomfort and being the target of substantial social stigma are so intolerable that they may discontinue the treatment even if it is effective. The paper reviews actual epidemiological data concerning drug induced weight gain and associated health problems in psychiatric patients : there is a high risk of overweight, obesity, impaired glucose tolerance, diabetes mellitus, premature death, in patients with schizophrenia or bipolar disorder; and the effects of specific drugs on body weight: Tricyclic Antidepressants (TCA) induced weight gain correlated positively with dosage and duration of treatment, more pronounced with amitriptyline ; Selective Serotonin Reuptake Inhibitors (SSRI) decrease transiently bodyweight during the first few weeks of treatment and may then increase bodyweight; weight gain appears to be most prominent with some mood stabilizers (lithium, valproate); atypical antipsychotics tend to cause more weight gain than conventional ones and weight gain, diabetes, dyslipidemia, seem to be most severe with clozapine and olanzapine. Conceming the underlying mechanisms of drug induced weight gain, medications might interfere with central nervous functions regulating energy balance; patients report about: increase of appetite for sweet and fatty foods or "food craving" (antidepressants, mood stabilizers, antipsychotic drugs) and weight gain despite reduced appetite which can be explained by an altered resting metabolic rate (TCA, SSRI, Monoaminoxidase Inhibitors MAO I). According to current concepts, appetite and feeding are regulated by a complex of neurotransmitters, neuromodulators, cytokines and hormones interacting with the hypothalamus, including the leptin and the tumor necrosis factor system. The pharmacologic mechanisms underlying weight gain are presently poorly understood: maybe the different activities at some receptor systems may induce it, but also genetic predisposition. Understanding of the metabolic consequences of psychotropic drugs (weight gain, diabetes, dyslipidemia) is essential: the insulin-like effect of lithium is known; treatment with antipsychotic medications increases the risk of impaired glucose tolerance and diabetes mellitus. Several management options of weight gain are available from choosing or switching to another drug, dietary advices, increasing physical activities, behavioural treatment, but the best approach seems to attempt to prevent the weight gain : patients beginning maintenance therapy should be informed of that risk, and nutritional assessment and counselling should be a routine part of treatment management, associated with monitoring of weight, BMI, blood pressure, biological parameters (baseline and three months monitoring of fasting glucose level, fasting cholesterol and triglyceride levels, glycosylated haemoglobin). Psychiatrics must pay attention to concomitant medications and individual factors underlying overweight and obesity. Weight gain has been described since the discovery and the use of the firstpsychotropic drugs, but seems to intensify with especially some of the second generation antipsychotic medications ; understanding of the side effects of psychotropic drugs, including their metabolic consequences (weight gain, diabetes, dyslipidemia) is essential for the psychiatrics to avoid on the one hand a risk of lack of compliance, a discontinuation of the pharmacological medication and also a risk of relapse and rehospitalization, and on the other hand to avoid acute life threatening events (diabetic ketoacidocetosis and non ketotic hyperosmolar coma, long term risk complications of diabetes and overweight).
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PMID:[Psychotropic drugs induced weight gain: a review of the literature concerning epidemiological data, mechanisms and management]. 1638 18


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