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1.
Folia Morphol (Warsz) ; 81(3): 798-803, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34219214

RESUMO

Awareness of variations in the hepatic vasculature and biliary system is extremely important for avoiding iatrogenic injury in upper-abdominal surgery. The objective of this study is to describe a rare case of abnormal vascular and biliary structures in the hepatocystic triangle (HCT) (the modern Calot's triangle). During anatomical dissection of the coeliac trunk (CT) in an old man, the authors observed the presence of a hepatosplenic trunk arising from the CT and bifurcating into common hepatic and splenic arteries. The common hepatic artery divided into hepatic artery proper and gastroduodenal artery. The presence of accessory right hepatic artery (ARHA) arising from the superior mesenteric artery was also notable. The aberrant artery ascended retropancreatically ventral to the splenic vein, then posterolaterally to the portal vein before termination into the right hepatic lobe in the HCT. Within this triangle, there was an aberrant bile duct originating in the right hepatic lobe and ending in the common hepatic duct. This accessory duct crossed the ARHA and an associated branch (the cystic artery). There is no known previous report on the co-existence of an ARHA and an aberrant bile duct within the HCT, in addition to the hepatosplenic trunk. The clinical implications of the current case are addressed in discussion.


Assuntos
Ductos Biliares , Artéria Hepática , Artéria Celíaca , Humanos , Fígado , Masculino , Artéria Mesentérica Superior
2.
Mol Cell Biochem ; 476(12): 4301-4321, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34420186

RESUMO

Allium species, belonging to Alliaceae family, are among the oldest cultivated vegetables used as food. Garlic, onions, leeks and chives, which belong to this family, have been reported to have medicinal properties. The Allium species constituents have been shown to have antibacterial and antioxidant activities, and, in addition, other biological properties. These activities are related to their rich organosulfur compounds. These organosulfur compounds are believed to prevent the development of cancer, cardiovascular, neurological, diabetes, liver diseases as well as allergy and arthritis. There have also been reports on toxicities of these compounds. The major active compounds of Allium species includes, diallyl disulfide, diallyl trisulfide, diallyl sulfide, dipropyl disulfide, dipropyl trisulfide, 1-propenylpropyl disulfide, allyl methyl disulfide and dimethyl disulfide. The aim of this review is to focus on a variety of experimental and clinical reports on the effectiveness, toxicities and possible mechanisms of actions of the active compounds of garlic, onions, leek and chives.


Assuntos
Allium/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Neoplasias/tratamento farmacológico , Plantas Medicinais/química , Allium/metabolismo , Animais , Anti-Infecciosos/química , Antioxidantes/química , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Plantas Medicinais/metabolismo
3.
Chem Biol Interact ; 310: 108737, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279792

RESUMO

AIMS: K117 and K127 are bis-pyridinium aldoximes but K117 is a bis-pyridinium bis-aldoxime while K127 has only one single aldoxime in addition to its amide substituent. Is there any difference in pharmacokinetics in these compounds that otherwise have the same chemical structure? Both K117 and K127 are developed as antidotes in acetylcholinesterase and butyrylcholinesterase poisoning in terrorist attacks or intoxication with other organophosphorous compounds. Their distributions have been scouted in the bodies of rats. MAIN METHODS: White male Wistar rats were intramuscularly injected. The animals were sacrificed, tissue samples were homogenized, and either K117 or K127 concentrations were determined using reversed-phase high-performance liquid chromatography. KEY FINDINGS: Both K117 and K127 were present in all tissues that were analyzed including blood (serum), the brains, cerebrospinal fluid, the eyes, livers, kidneys, lungs and testes. Their pharmacokinetics and body distributions are similar. SIGNIFICANCE: Either K117 or K127 meets the essential requirements for antidotes. Dose dependence and kinetics of their distribution were compared to that of other pyridinium aldoximes.


Assuntos
Antídotos/farmacocinética , Organofosfatos/antagonistas & inibidores , Oximas/farmacocinética , Compostos de Piridínio/farmacocinética , Acetilcolinesterase/química , Animais , Butirilcolinesterase/química , Substâncias para a Guerra Química/farmacocinética , Inibidores da Colinesterase/farmacocinética , Reativadores da Colinesterase/farmacocinética , Oximas/análise , Compostos de Piridínio/análise , Ratos , Ratos Wistar , Distribuição Tecidual
4.
Mol Cell Biochem ; 455(1-2): 109-118, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30478677

RESUMO

We investigated the effects of 20 days of dehydration and 20 days of dehydration followed by 72 h of rehydration on the gastric mucosa of the one-humped dromedary camel. The parameters addressed include biomarkers of oxidative stress, apoptosis, gastric epithelial histology, gastric neuropeptides, and their receptors. Nineteen clinically healthy, 4-5 year-old male dromedary camels were divided into three groups (five control camels, eight dehydrated for 20 days, six dehydrated for 20 days and then rehydrated for 72 h). Dehydration affected the oxidative stress biomarkers causing a significant increase in malondialdehyde, glutathione, nitric oxide, and catalase values compared with controls. Also the results revealed that dehydration caused different size cellular vacuoles and focal necrosis in the gastric mucosa. Rehydration for 72 h resulted in improvement in some parameters but was not enough to fully abolish the effect of dehydration. Dehydration caused significant increase in apoptotic markers; tumor necrosis factor α, caspases 8 and 3, BcL-x1 and TGFß whereas caspase 9, p53, Beclin 1, and PARP1 showed no significant change between the three groups indicating that apoptosis was initiated by the extrinsic pathway. Also there were significant increases in prostaglandin E2 receptors and somatostatin in plasma and gastric epithelium homogenate, and a significant decrease in cholecystokinin-8 receptors. A significant decrease of hydrogen potassium ATPase enzyme activity was also observed. Pepsinogen C was not affected by dehydration. It is concluded that long-term dehydration induces oxidative stress and apoptosis in camel gastric mucosa and that camels adjust gastric functions during dehydration towards water economy. More than 72 h are needed before all the effects of dehydration are reversed by rehydration.


Assuntos
Apoptose , Camelus/metabolismo , Desidratação/metabolismo , Mucosa Gástrica/metabolismo , Neuropeptídeos/metabolismo , Estresse Oxidativo , Animais , Biomarcadores/metabolismo , Desidratação/patologia , Desidratação/veterinária , Mucosa Gástrica/patologia , Masculino
5.
J Appl Toxicol ; 35(2): 116-23, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25291712

RESUMO

This paper reviews the blood-brain barrier (BBB) penetration of newly developed pyridinium aldoximes. Pyridinium aldoximes are highly charged hydrophilic compounds used in the treatment of subjects exposed to organophosphonates because they are effective as acetylcholinesterase reactivators. Pyridinium aldoximes have antidotal effects against poisoning with cholinesterase inhibitors, a frequent problem affecting people working with organophosphate-based insecticides and pesticides. Toxic organophosphonate products such as sarin and tabun can be used by terrorists as chemical warfare agents. This poses a severe challenge to all innocent and peace-loving people worldwide. This review gives a brief summary of BBB transporters and description of the current in vitro and in vivo methods for the characterization of BBB penetration of established and novel pyridinium aldoximes. The authors provide a putative mechanism of penetration, outline some future ways of formulation and discuss the possible advantages and disadvantages of increasing BBB penetration.


Assuntos
Barreira Hematoencefálica/metabolismo , Reativadores da Colinesterase/farmacocinética , Oximas/farmacocinética , Compostos de Piridínio/farmacocinética , Animais , Antídotos/farmacocinética , Antídotos/uso terapêutico , Humanos , Intoxicação por Organofosfatos/tratamento farmacológico
6.
Curr Med Chem ; 21(13): 1522-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24350849

RESUMO

Selegiline (1) [(-)-deprenyl] is used to treat patients with Parkinson's disease. Nevertheless, in much higher doses it has beneficial effects in depression, and dementia of the aged patients. Selegiline (1) undergoes a complex metabolic pathway. Its major metabolites include (-)-desmethyldeprenyl (2), (-)-methamphetamine (3) and (-)-amphetamine (4), deprenyl-N-oxide (5) and formaldehyde (6) as a small metabolic fragment. In addition, more than 40 minor metabolites of selegiline (1) have also been either detected or proposed by investigators and researchers. This review analyses the pharmacological activity, generation pathway and the detection method of the major metabolites of selegiline (1).


Assuntos
Selegilina/metabolismo , Animais , Ensaios Clínicos como Assunto , Interações Medicamentosas , Humanos , Selegilina/química , Selegilina/farmacologia
7.
Curr Med Chem ; 19(33): 5683-704, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22934779

RESUMO

Metabolic fate plays an important role in the elimination of drugs and other foreign compounds from the body. Metabolism through various enzyme systems, makes the parent compound more hydrophilic, thus, it can be readily excreted from the body. Some active metabolites of drugs are produced following N-, O-, and S-desalkylation. These metabolites are either more or less potent, or as potent as their parent drugs. The removal of alkyl groups from tertiary aliphatic and acyclic amines is carried out by hepatic cytochrome P450 mixed-function oxidase enzymes. Several drugs undergo this process, which yields free hydroxyl-, or amino-groups, in addition to aldehyde from the splitted alkyl group. Metabolism of drugs into clinically active compounds indicates an extra target of therapeutic drug monitoring. Numerical data of logP values show how lipophilicity changes through metabolism to facilitate excretion. The example of phenacetin - paracetamol opened up a way for improving pharmacological effect by the use of a metabolite. This review gives a detailed description of these drugs, their active and major metabolites found in humans or animals, metabolizing cytochrome P450s, and the most recent analytical methods for their determination.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Animais , Química Farmacêutica , Humanos , Oxirredução
8.
Curr Drug Metab ; 13(6): 835-62, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22571480

RESUMO

Decarboxylation, reduction and hydrolysis can yield active metabolites from the parent drug. Major therapeutic indications and metabolic routes of these drugs are reviewed. Changes in the logP values (determined and calculated) from the parent drug to the active metabolite show certain characteristics in comparison to other phase I metabolic alterations. Metabolic decarboxylation of parent drug is commonly associated with increase in lipophilicity. However, in some cases, decarboxylation may cause a reduction in lipophilicity. Ester hydrolysis generally unmasks either the polar carboxylic or hydroxyl group with the outcome of an increase in hydrophilicity. On the contrary, hydrolysis of phosphate ester means a huge increase in the lipophilic character of the drug, as the highly polar phosphate group is removed.


Assuntos
Preparações Farmacêuticas/metabolismo , Biotransformação , Descarboxilação , Ésteres/metabolismo , Humanos , Hidrólise , Oxirredução
9.
Mol Cell Biochem ; 361(1-2): 267-80, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22009485

RESUMO

There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The objective of the study was to investigate ventricular myocyte shortening, intracellular Ca(2+) signalling and expression of genes encoding cardiac muscle proteins in the aged Zucker diabetic fatty (ZDF) rat. There was a fourfold elevation in non-fasting blood glucose in ZDF rats (478.43 ± 29.22 mg/dl) compared to controls (108.22 ± 2.52 mg/dl). Amplitude of shortening, time to peak (TPK) and time to half (THALF) relaxation of shortening were unaltered in ZDF myocytes compared to age-matched controls. Amplitude and THALF decay of the Ca(2+) transient were unaltered; however, TPK Ca(2+) transient was prolonged in ZDF myocytes (70.0 ± 3.2 ms) compared to controls (58.4 ± 2.3 ms). Amplitude of the L-type Ca(2+) current was reduced across a wide range of test potentials (-30 to +40 mV) in ZDF myocytes compared to controls. Sarcoplasmic reticulum Ca(2+) content was unaltered in ZDF myocytes compared to controls. Expression of genes encoding cardiac muscle proteins, membrane Ca(2+) channels, and cell membrane ion transport and intracellular Ca(2+) transport proteins were variously altered. Myh6, Tnnt2, Cacna2d3, Slc9a1, and Atp2a2 were downregulated while Myl2, Cacna1g, Cacna1h, and Atp2a1 were upregulated in ZDF ventricle compared to controls. The results of this study have demonstrated that preserved ventricular myocyte shortening is associated with altered mechanisms of Ca(2+) transport and a changing pattern of genes encoding a variety of Ca(2+) signalling and cardiac muscle proteins in aged ZDF rat.


Assuntos
Sinalização do Cálcio , Tamanho Celular , Diabetes Mellitus Tipo 2/fisiopatologia , Contração Miocárdica , Miócitos Cardíacos/fisiologia , RNA Mensageiro/metabolismo , Animais , Canais de Cálcio Tipo L/metabolismo , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Expressão Gênica , Masculino , Potenciais da Membrana , Miócitos Cardíacos/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Zucker , Retículo Sarcoplasmático/metabolismo
10.
Curr Med Chem ; 18(32): 4885-900, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22050741

RESUMO

About one hundred and fifty of the several thousands of drugs on the market are known to have active metabolites. Medicinal chemistry of the parent drugs as well as that of the metabolites are very important both in medical practice and drug research. The efficacy of a drug will depend on a number of properties including, pharmacokinetic behavior, absorption, tissue distribution, pharmacological potency, toxicity and tissue-specificity. The production and release of active metabolites are important because active drug metabolites may influence the clinical outcome of a drug by increasing the gross level of pharmacologically active compounds (drug + active metabolite) and/or essentially increasing the duration of drug effect, when t(1/2) of active metabolite is much longer than that of the parent drug. Furthermore, certain drug metabolizing enzymes can either be inhibited or induced by other drugs and a variety of food and environmental factors. A careful control of the clinical effects of any drug with active metabolites is important especially in the treatment of the elderly population where the administration of several drugs is not unusual.This review provides a detailed description of the medicinal chemistry of drugs yielding active metabolites after undergoing transformation via aliphatic and aromatic oxidations, epoxidation and S-oxidation. Their respective pharmacologically active metabolites, metabolizing enzymes and changes in lipophilicity are also summarized. The most recent analytical methods used for the reliable quantification of both the parent drugs and their metabolites are also included.


Assuntos
Preparações Farmacêuticas/metabolismo , Pró-Fármacos/metabolismo , Química Farmacêutica , Compostos de Epóxi/química , Compostos de Epóxi/metabolismo , Humanos , Hidroxilação , Modelos Químicos , Oxirredução , Preparações Farmacêuticas/química , Farmacocinética , Pró-Fármacos/química , Pró-Fármacos/farmacocinética
11.
Exp Physiol ; 96(3): 325-37, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21216827

RESUMO

The association between type 2 diabetes and obesity is very strong, and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The aim of this study was to investigate early changes in the pattern of genes encoding cardiac muscle regulatory proteins and associated changes in ventricular myocyte contraction and Ca(2+) transport in young (9- to 13-week-old) type 2 Zucker diabetic fatty (ZDF) rats. The amplitude of myocyte shortening was unaltered; however, time-to-peak shortening and time to half-relaxation of shortening were prolonged in ZDF myocytes (163 ± 5 and 127 ± 7 ms, respectively) compared with age-matched control rats (136 ± 5 and 103 ± 4 ms, respectively). The amplitude of the Ca(2+) transient was unaltered; however, time-to-peak Ca(2+) transient was prolonged in ZDF myocytes (66.9 ± 2.6 ms) compared with control myocytes (57.6 ± 2.3 ms). The L-type Ca(2+) current was reduced, and inactivation was prolonged over a range of test potentials in ZDF myocytes. At 0 mV, the density of L-type Ca(2+) current was 1.19 ± 0.28 pA pF(-1) in ZDF myocytes compared with 2.42 ± 0.40 pA pF(-1) in control myocytes. Sarcoplasmic reticulum Ca(2+) content, release and uptake and myofilament sensitivity to Ca(2+) were unaltered in ZDF myocytes compared with control myocytes. Expression of genes encoding various L-type Ca(2+) channel proteins (Cacna1c, Cacna1g, Cacna1h and Cacna2d1) and cardiac muscle proteins (Myh7) were upregulated, and genes encoding intracellular Ca(2+) transport regulatory proteins (Atp2a2 and Calm1) and some cardiac muscle proteins (Myh6, Myl2, Actc1, Tnni3, Tnn2, and Tnnc1) were downregulated in ZDF heart compared with control heart. A change in the expression of genes encoding myosin heavy chain and L-type Ca(2+) channel proteins might partly underlie alterations in the time course of contraction and Ca(2+) transients in ventricular myocytes from ZDF rats.


Assuntos
Sinalização do Cálcio , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Ventrículos do Coração/metabolismo , Miócitos Cardíacos/metabolismo , Disfunção Ventricular/genética , Disfunção Ventricular/metabolismo , Citoesqueleto de Actina/metabolismo , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Regulação para Baixo , Regulação da Expressão Gênica , Ventrículos do Coração/fisiopatologia , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Contração Miocárdica/genética , Contração Miocárdica/fisiologia , Miócitos Cardíacos/fisiologia , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Ratos , Ratos Zucker , Retículo Sarcoplasmático/metabolismo , Disfunção Ventricular/fisiopatologia
12.
Physiol Res ; 60(1): 65-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20945962

RESUMO

Diabetes mellitus is associated with a variety of cardiovascular complications including impaired cardiac muscle function. The effects of insulin treatment on heart rate, body temperature and physical activity in the alloxan (ALX)-induced diabetic rat were investigated using in vivo biotelemetry techniques. The electrocardiogram, physical activity and body temperature were recorded in vivo with a biotelemetry system for 10 days before ALX treatment, for 20 days following administration of ALX (120 mg/kg) and thereafter, for 15 days whilst rats received daily insulin. Heart rate declined rapidly after administration of ALX. Pre-ALX heart rate was 321+/-9 beats per minute, falling to 285+/-12 beats per minute 15-20 days after ALX and recovering to 331+/-10 beats per minute 5-10 days after commencement of insulin. Heart rate variability declined and PQ, QRS and QT intervals were prolonged after administration of ALX. Physical activity and body temperature declined after administration of ALX. Pre-ALX body temperature was 37.6+/-0.1 °C, falling to 37.3+/-0.1 °C 15-20 days after ALX and recovering to 37.8+/-0.1 °C 5-10 days after commencement insulin. ALX-induced diabetes is associated with disturbances in heart rhythm, physical activity and body temperature that are variously affected during insulin treatment.


Assuntos
Temperatura Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Aloxano/administração & dosagem , Aloxano/farmacologia , Animais , Glicemia , Diabetes Mellitus Experimental/metabolismo , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar
13.
Anal Bioanal Chem ; 398(1): 295-312, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20585942

RESUMO

This paper discusses the current methods used for quantitative determination of analogues of nucleotide reverse transcriptase inhibitors (NtRTIs) in body fluids, cells, and tissues. Nucleoside reverse transcriptase inhibitors (NRTIs) prodrugs given to AIDS/herpes/cancer patients conjugate with phosphates at the site of their action. Separation of phosphorylated NRTIs is generally performed by reversed-phase chromatography. After separation, plasma NRTIs can be detected using a variety of methods, including immunoassay through monitoring of UV absorbance, fluorescence, and mass spectrometry. The most recent development in the field of detection of plasma NtRTIs shows a tendency toward the use double- or triple-focusing mass spectrometry, the most specific and sensitive monitoring technique.


Assuntos
Antineoplásicos/isolamento & purificação , Antivirais/isolamento & purificação , Cromatografia/métodos , Nucleosídeos/isolamento & purificação , DNA Polimerase Dirigida por RNA/química , Inibidores da Transcriptase Reversa/isolamento & purificação , Humanos
14.
Mini Rev Med Chem ; 10(9): 822-45, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20491651

RESUMO

Certain xenobiotics are given in the "prodrug" form. Either the human body, or one compartment of the body, or the targeted virus itself metabolizes the prodrug into its active form. The bioprecursor form of drugs is used for a wide variety of reasons, namely: to make drug penetration into the target organ (mainly to the brain through the blood-brain-barrier) possible, eliminate unpleasant taste, alter (either increasing or decreasing) the half life of the active component or supply more than one active components to the body.


Assuntos
Antineoplásicos/química , Antivirais/química , Fosfatos/química , Pró-Fármacos/química , Antineoplásicos/uso terapêutico , Antivirais/uso terapêutico , Química Farmacêutica , Humanos , Neoplasias/tratamento farmacológico , Pró-Fármacos/uso terapêutico
15.
Exp Clin Endocrinol Diabetes ; 118(10): 699-707, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20496316

RESUMO

The morphological and biochemical changes that occur in the early phase of streptozotocin (STZ)-induced beta cell failure have not been characterized. The pancreas and plasma of rats treated with STZ were processed for morphological and biochemical parameters 1-24 h and 4 weeks after STZ treatment. Marked reduction in body weight was observed as early as 3 h post STZ treatment and hyperglycemia coupled with hypoinsulinaemia appeared in rats 1 h after treatment with STZ. Hyperglycemia, hyperglucagonemia and hypoinsulinemia became permanent 24 h after STZ treatment. The number of insulin-positive cells decreased significantly (p<0.05) at 24 h after STZ treatment with a concomitant increase in the number of glucagon-immunoreactive cells. Electron microscopy showed coalescing of beta cell granules 18 h after STZ treatment. A near to complete degranulation of beta cells settled at 21 h after STZ administration. The pancreatic tissue and plasma levels of adrenaline and noradrenaline increased significantly (p<0.004: pancreatic tissue; p<0.04: plasma) 3 h after STZ treatment and remained high after a reduction at 6 h post STZ treatment. The pancreatic tissue and plasma levels of 5-HIAA decreased significantly (p<0.002 pancreatic tissue; p<0.04: plasma) 1 h after STZ treatment and remained low after a reduction at 6-9 h post STZ treatment. STZ elicited significant dose-dependent increases in insulin secretion from the isolated pancreas. The early changes in catecholamine level may be used in screening and follow-up studies on diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/ultraestrutura , Estreptozocina/toxicidade , Animais , Degranulação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Epinefrina/sangue , Glucagon/sangue , Glucagon/metabolismo , Ácido Hidroxi-Indolacético/sangue , Ácido Hidroxi-Indolacético/metabolismo , Hiperglicemia/induzido quimicamente , Técnicas In Vitro , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/fisiologia , Masculino , Norepinefrina/sangue , Concentração Osmolar , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Ratos , Ratos Wistar , Vesículas Secretórias/efeitos dos fármacos , Vesículas Secretórias/metabolismo , Vesículas Secretórias/ultraestrutura , Fatores de Tempo , Redução de Peso/efeitos dos fármacos
16.
Curr Med Chem ; 17(6): 517-51, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20015035

RESUMO

Diabetes mellitus is a common disease and contributes to a high degree of morbidity and mortality. Cardiovascular complications, including diabetic cardiomyopathy are major causes of morbidity and mortality in diabetic patients. Diabetic cardiomyopathy is a condition that affects the myocardium, primarily. It is not necessarily associated with ischemic heart disease, high blood pressure, valvular or congenital anomalies. The pathology of diabetic cardiomyopathy includes interstitial fibrosis, apoptosis of cardiomyocytes, abnormal energy utilization, small vessel disease and cardiac neuropathy. These pathologies are induced by hyperglycemia and oxidative stress. Biochemical as well as electrolyte changes, especially reduced calcium availability also occurs in the myocardium of diabetic patients. The abnormal structure and biochemistry of the myocardium result in functional problems such as diastolic and systolic dysfunctions, which may cause symptoms of dyspnea and inability to tolerate exercise. No single specific therapeutic agent can treat diabetic cardiomyopathy because once the disease is overt, the management may require a variety of approaches such as risk factors and lifestyle modification, glucose control (insulin, alpha glucosidase inhibitors, sulfonylureas, biguanides, meglitinides, thiazolidinediones and dipeptidyl peptidase 4 (DPP-4) inhibitors); hormones (IGF-1); ACE inhibitors (captopril, enalapril); angiotensin II receptor antagonists (losartan, olmesartan); beta adrenoreceptor antagonists (acebutolol, carvedilol); peptides (adrenomedullin); endothelin-1 receptor antagonists (bosentan, tezosentan); calcium channel blockers (amlodipine, verapamil); antioxidants (methalothionein, alpha tocopherol, alpha lipoic acid) and antihyperlipidemic drugs (simvastatin, fenofibrate, ezetimibe) to effectively treat patients with diabetic cardiomyopathy.


Assuntos
Cardiomiopatias/tratamento farmacológico , Complicações do Diabetes/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/uso terapêutico , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/uso terapêutico , Cardiomiopatias/etiologia , Endotelina-1/antagonistas & inibidores , Endotelina-1/metabolismo , Fenofibrato/análogos & derivados , Fenofibrato/química , Fenofibrato/uso terapêutico , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Receptores Ativados por Proliferador de Peroxissomo/antagonistas & inibidores , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores de Angiotensina/metabolismo
17.
Mol Cell Biochem ; 328(1-2): 57-65, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19267230

RESUMO

Ventricular electrical conduction has been investigated in the streptozotocin (STZ)-induced diabetic rat. Diabetes was induced with a single injection of STZ (60 mg/kg bodyweight, ip). The ECG was measured continuously, in vivo, using a biotelemetry system. Left ventricular action potentials were recorded with an extracellular suction electrode. Expression of mRNA transcripts for selected ion transport proteins was measured in left ventricle with real-time RT-PCR. At 10 weeks after STZ treatment, in vivo heart rate (HR) was reduced (267 +/- 3 vs. 329 +/- 5 BPM), QRS complex duration and QT interval were prolonged in diabetic rats compared to controls. In vitro spontaneous HR was reduced and paced heart action potential repolarization was prolonged in diabetic rats compared to controls. The mRNA expression for Kcnd2 (I (to) channel) and Kcne2 (I (kr) channel) was significantly reduced in diabetic rats compared to controls. Altered gene expression and, in particular, genes that encode K(+) channel proteins may underlie delayed propagation of electrical activity in the ventricular myocardium of STZ-induced diabetic rat.


Assuntos
Potenciais de Ação , Diabetes Mellitus Experimental/fisiopatologia , Regulação da Expressão Gênica , Ventrículos do Coração/fisiopatologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Canais de Potássio Shal/genética , Animais , Eletrocardiografia , Frequência Cardíaca , Miocárdio/metabolismo , RNA Mensageiro/análise , Ratos
18.
Ann N Y Acad Sci ; 1084: 402-10, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17151318

RESUMO

The one-humped camel is a typical desert animal. It has the capability of withstanding the harsh climatic changes and the scarcity of food and water, in addition to the high-ambient temperature. The prevalence of diabetes mellitus in two different groups of the one-humped camel, group (A) control (n = 102) camels and group (B) high-calorie diet-fed camels (n = 103), in Al-Ain region (UAE) was studied using biochemical and radioimmunoassay techniques. In this article, 7% of the control camels have diabetes mellitus (blood glucose level: > or =140 mg/dL) compared to 21% of the high-calorie-fed camels. Plasma insulin level was significantly (P < 0.05) lower in group B compared to group A. The low insulin level in camels consuming high-caloric diet could be a sign of exhaustion of pancreatic beta cells. The hematological parameters were nearly similar in both groups and no significant differences were seen. Liver and kidney enzymes were normal in both groups. Iron and copper were significantly (P < 0.005) higher in the high-calorie-fed camels compared with the control. Our study indicates that high-caloric feed consumption in camels is associated with the development of disorders in glucose metabolism leading to diabetes mellitus.


Assuntos
Diabetes Mellitus/veterinária , Dieta , Ingestão de Energia , Animais , Cruzamento , Camelus , Diabetes Mellitus/epidemiologia , Contagem de Eritrócitos , Feminino , Contagem de Leucócitos , Prevalência
19.
Clin Exp Pharmacol Physiol ; 33(4): 327-31, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16620296

RESUMO

1. Streptozotocin (STZ)-induced diabetic cardiomyopathy is frequently associated with depressed diastolic/systolic function and altered heart rhythm. 2. The effects of insulin treatment on heart rhythm, body temperature and physical activity in STZ-induced diabetic rats were investigated using biotelemetry techniques. 3. Transmitter devices were surgically implanted in the peritoneal cavity of young adult male Wistar rats. Electrodes from the transmitter were arranged in Einthoven bipolar - Lead II configuration. Electrocardiogram, physical activity and body temperature data were recorded with a telemetry system for 10 days before STZ treatment, for 20 days following administration of STZ (60 mg/kg) and thereafter, for 30 days while rats received daily insulin. 4. Heart rate, physical activity and body temperature declined rapidly 3-5 days after administration of STZ. Pre-STZ heart rate was 362 +/- 7 b.p.m., falling to 266 +/- 12 b.p.m. 5-15 days after STZ with significant recovery to 303 +/- 14 b.p.m. 10-20 days after commencement of insulin. Pre-STZ body temperature was 37.5 +/- 0.1C, falling to 37.2 +/- 0.2C 5-15 days after STZ with significant recovery to 37.5 +/- 0.1C 10-20 days after commencement of insulin. Physical activity and heart rate variability were also reduced after STZ but there was no significant recovery during insulin replacement. 5. Defective autonomic regulation and/or mechanisms of control that are intrinsic to the heart may underlie disturbances in heart rhythm in the STZ-induced diabetic rat.


Assuntos
Temperatura Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Diabetes Mellitus Experimental/psicologia , Atividade Motora/fisiologia , Ratos , Telemetria
20.
Mol Cell Biochem ; 280(1-2): 159-63, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16311918

RESUMO

The long-term clinical effects of ACE-inhibitors have similarities with those of both fibrates and glitazones, activators of peroxisome proliferator activator receptor (PPAR) alpha and gamma, respectively. The antioxidant enzyme catalase, a heme protein that degrades hydrogen peroxide, is found at high concentrations in peroxisomes. Catalase activity is one of the recognized surrogate markers indicative of PPAR activation in the rat liver. The purpose of the study was to establish the effect of moexipril on catalase activity and to compare it with the effect of both saline controls and that of the known PPAR agonist clofibrate (positive control). Three groups of seven rats were used. All substances were applied i.p. daily for 5 days, followed by a 2-day break. The cycle was repeated eight times. After the final cycle (day 56) the animals were sacrificed and liver tissue collected. The number of catalase positive cells in both moexipril group (95% CI 57-61) and clofibrate group (95% CI 72-80) is higher than in controls (95% CI 3-16) (p < or = 0.01). The number of catalase positive cells in the clofibrate group is higher than in the moexipril group (p < or = 0.01). High-dose subchronic exposure to the ACE-inhibitor moexipril induces catalase activity in the rat liver to an extent comparable to fibrates. We suggest that some of the long-term advantages of ACE inhibitor use - beyond mere BP lowering - might be due to a PPAR mediated effect.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Catalase/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Tetra-Hidroisoquinolinas/administração & dosagem , Tetra-Hidroisoquinolinas/farmacologia , Animais , Fígado/citologia , Ratos , Ratos Wistar
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