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1.
J Natl Med Assoc ; 109(2): 139-141, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28599755

RESUMO

The purpose of this paper is to report the dramatic changes in the point prevalence of diabetes mellitus in the adult population of Jamaica following education intervention. The initial prevalence in the 15-and-over age group was determined by a two-stage stratified random sampling design in 1993. In 1997, the University of the West Indies Diabetes Outreach Project thru its public service arm, the Diabetes Association of Jamaica, developed and implemented a Peer Facilitators Diabetes Education Programme. This effort has realized an increased patient and public education as well as concomitant increased patient compliance and a reduction in related complications. The Jamaica Health and Lifestyle Survey 2008 examined, using a stratified, random, two-stage cluster sample survey, and a nationally representative sample of 2848 Jamaicans aged 15-74. The most dramatic outcome is the decrease in the prevalence from 17.9% to 7.9% in the adult population, age 15+.


Assuntos
Diabetes Mellitus/epidemiologia , Adolescente , Adulto , Idoso , Diabetes Mellitus/prevenção & controle , Feminino , Inquéritos Epidemiológicos , Humanos , Jamaica/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
2.
BMJ Open ; 3(7)2013.
Artigo em Inglês | MEDLINE | ID: mdl-23847264

RESUMO

OBJECTIVES: To compare obese versus non-obese Jamaican adolescents' risk for type 2 diabetes (T2D) and cardiovascular diseases (CVDs); and to explore a suitable and economical method of screening for these risk factors in the school settings. DESIGN: A descriptive cross-sectional study of adolescents' risk for T2D and CVD. All the participants were examined at their respective schools. SETTING: Jamaica, West Indies. POPULATION: 276 Jamaican adolescents aged 14-19 years, randomly selected from grades 9 to 12 from 10 high schools on the island and included both boys and girls. All ethnicities on the island were represented. MAIN OUTCOME MEASURES: High fasting blood glucose, total cholesterol, glycated haemoglobin (HbA1c), blood pressure, body mass index (BMI), waist circumference, waist-to-hip ratio, family history of obesity, T2D and CVDs, low physical activity, and presence of Acanthosis Nigricans. All blood measures were analysed using the finger prick procedure. RESULTS: Waist circumference, waist-to-hip ratio, Acanthosis Nigricans, total cholesterol, family history of T2D and blood pressure were the strongest predictors of BMI (p=0.001). Over one-third of the participants were overweight. Jamaican adolescent females had a significantly higher number of risk factors and were less physically active than males (p<0.05). Over 80% of participants reported ≥3 risk factors for T2D and CVD. Participants with BMI ≥25 reported five or more risk factors. One-third of the overweight participants were classified with metabolic syndrome. CONCLUSIONS: Jamaican adolescents are at risk of T2D and CVD. Family history of disease and anthropometric measures identified more participants at risk than did the blood measures. Jamaican adolescent females reported more risk factors for T2D and CVD as compared to males. Collection of this type of data was feasible within the school settings. All data were collected in 1 day per school. Intervention measures are needed to educate Jamaican adolescents to reduce overweight and subsequently the risk factors.

3.
Fam Pract ; 27 Suppl 1: i46-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19965903

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effectiveness of lay diabetes facilitators (LDFs) to increase knowledge and improve control among persons with diabetes. Methodology. A prospective cohort study was conducted among persons with diabetes in 16 health care centres in Jamaica to evaluate the effect of LDFs on glycaemia [haemoglobin A1c (HbA1c)] and body mass index (BMI). One hundred and fifty-nine persons with diabetes were recruited for the intervention from eight clinical settings in which LDFs had been recruited and trained. A matched group of 159 were recruited as a comparison sample from eight clinical settings without LDFs. HbA1c and BMI were measured at baseline and 6 months. RESULTS: Mean HbA1c at baseline for the intervention and comparison groups were 7.9% and 8%, respectively. After 6 months, the intervention group showed a mean decrease of 0.6% while the comparison group showed an increase of 0.6%, significant after control for potential confounders (P < 0.05). There was no statistically significant change in BMI between groups. CONCLUSION: Patients educated by LDFs showed improved metabolic control over the first 6 months of observation.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Educação de Pacientes como Assunto , Grupo Associado , Autocuidado , Adulto , Idoso , Glicemia/análise , Índice de Massa Corporal , Serviços de Saúde Comunitária , Diabetes Mellitus Tipo 2/sangue , Exercício Físico , Feminino , Hemoglobina A Glicada/metabolismo , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Jamaica , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Socioeconômicos
4.
J Lab Physicians ; 2(1): 25-30, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21814403

RESUMO

AIMS: Previous studies have shown that diabetes mellitus (DM) increases the risk of cardiovascular diseases in females to a greater extent than in males. In this cross-sectional study, we evaluated the lipid profiles of type 2 diabetic males and females. MATERIALS AND METHODS: The study included 107 type 2 diabetic patients (41 males and 66 females), and 122 hypertensive type 2 diabetic patients (39 males and 83 females), aged 15 years and older. Total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), very low density lipoprotein-cholesterol (VLDL-C) and high density lipoprotein-cholesterol (HDL-C) concentrations were assayed for each group using standard biochemical methods. RESULTS: The mean TC, TG, VLDL-C, HDL-C and LDL-C concentrations, TG/HDL and LDL/HDL ratios were higher in type 2 diabetic and hypertensive type 2 diabetic patients compared with non-diabetic, and hypertensive non-diabetic control subjects, although these were not significant (P > 0.05). Hypertensive type 2 diabetic females had significantly higher serum TC (7.42 ± 1.63 mmol/L) than hypertensive non-diabetic males (5.76±1.57 mmol/L; P < 0.05). All the other lipid and lipoprotein parameters except HDL-C were non-significantly higher in females with type 2 DM and those with hypertension and type 2 DM, compared with type 2 diabetic and hypertensive type 2 diabetic males, respectively (P > 0.05). CONCLUSION: This study demonstrated that dyslipidemia exists in our type 2 diabetic population with greater TC in hypertensive type 2 diabetic females compared with hypertensive type 2 diabetic males. This suggests that hypertensive type 2 diabetic females are exposed more profoundly to risk factors including atherogenic dyslipidemia compared with males.

5.
Arch Med Sci ; 6(5): 701-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22419928

RESUMO

INTRODUCTION: Hypertension and obesity are common problems among diabetic patients accelerating progression of vascular diabetic complications. MATERIALS AND METHODS: A two-stage stratified random sampling design was used, and individuals aged 15 years and over were interviewed. This cross-sectional study evaluated lipid abnormalities of 117 obese type 2 diabetic patients (28 males and 89 females), and 56 hypertensive obese type 2 diabetic patients (22 males and 34 females). Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C) and high-density lipoprotein cholesterol (HDL-C) concentrations were assayed using standard biochemical methods. RESULTS: Hypertensive obese type 2 diabetic females had significantly higher mean serum concentrations of TC (p = 0.043), TG (p = 0.046), LDL-C (p= 0.040), TC/HDL-C ratio (p = 0.001) and LDL-C/HDL-C ratio (p = 0.003) compared with hypertensive obese non-diabetic females. Similar results were found in hypertensive obese type 2 diabetic males compared with hypertensive obese non-diabetic males. Hypertensive obese type 2 diabetic females had significantly higher serum TC, TG and TC/HDL-C ratio (p < 0.05) than hypertensive obese type 2 diabetic males. Hypertensive obese type 2 diabetic females had significantly higher mean serum concentrations of TG (p = 0.03) and TC (p = 0.01) than obese type 2 diabetic females. There was a significant association between blood glucose and LDL-C concentrations in type 2 diabetic subjects (r = 0.36; p< 0.05). CONCLUSION: Obese hypertensive type 2 diabetic females are exposed more profoundly to risk factors including atherogenic dyslipidaemia compared with males.

6.
Ethn Dis ; 17(3): 522-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17985508

RESUMO

OBJECTIVES: To compare the prevalence, agreement and phenotypic characteristics in three ethnic groups of the new International Diabetes Federation (IDF) definition of metabolic syndrome (MS) to the World Health Organization (WHO) and national cholesterol education program (NCEP) definitions. SETTING: Newcastle upon Tyne, England. DESIGN: Cross-sectional surveys. PARTICIPANTS: Chinese (171 men and 185 women), European (257 men and 301 women), and South Asian (264 men and 295 women) adults, ages 25 to 64 years. MAIN OUTCOME MEASURES: Anthropometric indices: blood pressure, fasting lipids, urine albumin-to-creatinine ratio, glucose intolerance, insulin resistance. RESULTS: IDF-defined MS was highly prevalent in all groups, ranging from 12.3% (95% CIs 7.4-17.2) in Chinese men to 45.5% (39.5-51.5) in South Asian men. In women, of all ethnic groups, more than 80% of those with WHO- or NCEP-defined MS also had IDF-defined MS. In men, however, agreement was less good. For example, in each ethnic group, more than a third of those with WHO-defined MS did not have IDF-defined MS. Within each ethnic group, the biological characteristics of those with MS by any definition were largely the same. However, differences existed between ethnic groups. For example, in those with IDF-defined MS, both South Asian men and women had significantly (P < .05) higher insulin resistance and significantly lower systolic and diastolic blood pressure than Europeans or Chinese. CONCLUSIONS: Agreement between the IDF and other definitions is better in women than men. The phenotype is similar within each ethnic group whatever the definition, but differs between groups suggesting that risks associated with MS differ by ethnic group.


Assuntos
Antropometria , Síndrome Metabólica/epidemiologia , Terminologia como Assunto , Organização Mundial da Saúde , Adulto , Ásia/epidemiologia , China/epidemiologia , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Síndrome Metabólica/etnologia , Síndrome Metabólica/genética , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
7.
Mol Cell Biochem ; 297(1-2): 171-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17072757

RESUMO

In this study, we examined the cellular content of the insulin receptor substrate (IRS)-1, the levels of phosphorylated tyrosine (pY) and serine (pS) residues in IRS-1, and the glucose transporters GLUT-1 and GLUT-4 in primary cultured rat skeletal myocytes treated with the glucocorticoid, dexamethasone. Dexamethasone markedly increased basal and insulin-stimulated IRS-1 content 4 to 5-fold (p < 0.01). A similar level of increase was observed for IRS-1 pY content. However, dexamethasone treatment had no effect on IRS-1 pS content. Further, dexamethasone reduced the cellular content of GLUT-1 when insulin and glucose were absent (p < 0.05), but did not significantly affect the expression of GLUT-4 in the presence of insulin (p > 0.05). We conclude that dexamethasone treatment impairs insulin signalling by a mechanism independent of serine-phosphorylation-mediated IRS-1 depletion, or of impairment of GLUT-1 expression. Instead, dexamethasone-induced insulin resistance may be mediated via reduced cellular content of IRS-1 accompanied by parallel reduction in tyrosine phosphorylation in IRS-1.


Assuntos
Dexametasona/farmacologia , Insulina/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Células Cultivadas , Feminino , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Proteínas Substratos do Receptor de Insulina , Masculino , Fosfoproteínas/metabolismo , Fosfosserina/metabolismo , Fosfotirosina/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Mol Cell Biochem ; 293(1-2): 9-14, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16953337

RESUMO

This study was designed to understand the cellular mechanisms responsible for defects in the insulin-stimulated signal transduction pathway in a type 2 diabetic animal model. We examined the in vitro PC-1 phosphodiesterase activity and glucose uptake in adipose tissue of streptozotocin (STZ)-induced type 2 diabetic rats. The PC-1 activity was significantly increased in adipose tissue of diabetic rats (0.54 +/- 0.08 nmol PNTP hydrolyzed/mg protein/min) compared with controls (0.29 +/- 0.05 nmol PNTP hydrolyzed/mg protein/min, p < 0.05). Upon insulin stimulation (100 nM), glucose uptake in the adipose tissue of the controls (4.17 +/- 1.28 x 10(-8) micromol/mg/min) was significantly higher than that in the diabetic rats (1.26 +/- 0.35 x 10(-8); p < 0.05). These results suggest that elevated PC-1 phosphodiesterase activity and decreased glucose uptake in adipose tissues may be acquired characteristics contributing to the development of type 2 diabetes mellitus.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/enzimologia , Animais , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Tipo 2/enzimologia , Feminino , Insulina/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fatores de Tempo
9.
J Biosci ; 31(3): 347-54, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17006017

RESUMO

There is increasing evidence that endogenous nitric oxide (NO) influences adipogenesis, lipolysis and insulin-stimulated glucose uptake. We investigated the effect of NO released from S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylpenicillamine (SNAP) on basal and insulin-stimulated glucose uptake in adipocytes of normoglycaemic and streptozotocin (STZ)-induced diabetic rats. GSNO and SNAP at 0.2,0.5, and 1 mM brought about a concentration-dependent increase in basal and insulin-stimulated 2-deoxyglucose uptake in adipocytes of normoglycaemic and STZ-induced diabetic rats. SNAP at 1.0 mM significantly elevated basal 2-deoxyglucose uptake (115.8+/-10.4% compared with GSNO at the same concentration (116.1+/-9.4%; P less than 0.05) in STZ-induced diabetic rats. Conversely, SNAP at concentrations of 10 mM and 20 mM significantly decreased basal 2-deoxyglucose uptake by 50.0+/-4.5% and 61.5+/-7.2% respectively in adipocytes of STZ-induced diabetic rats (P less than 0.05). GSNO at concentrations of 10 mM and 20 mM also significantly decreased basal 2-deoxyglucose uptake by 50.8+/-6.4% and 55.2+/-7.8% respectively in adipocytes of STZ-induced diabetic rats (P less than 0.05). These observations indicate that NO released from GSNO and SNAP at 1 mM or less stimulates basal and insulin-stimulated glucose uptake,and at concentrations of 10 mM and 20 mM inhibits basal glucose uptake. The additive effect of GSNO or SNAP, and insulin observed in this study could be due to different mechanisms and warrants further investigation.


Assuntos
Adipócitos/efeitos dos fármacos , Glucose/metabolismo , Doadores de Óxido Nítrico/farmacologia , S-Nitroso-N-Acetilpenicilamina/farmacologia , S-Nitrosoglutationa/farmacologia , Adipócitos/metabolismo , Animais , Glicemia/análise , Diabetes Mellitus Experimental/metabolismo , Feminino , Insulina/sangue , Masculino , Ratos , Ratos Sprague-Dawley
10.
BMC Biochem ; 7: 17, 2006 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-16729893

RESUMO

BACKGROUND: Evidence demonstrates that exogenously administered nitric oxide (NO) can induce insulin resistance in skeletal muscle. We have investigated the modulatory effects of two NO donors, S-nitroso-N-acetyl-D, L-penicillamine (SNAP) and S-nitrosoglutathione (GSNO) on the early events in insulin signaling in rat skeletal myocytes. RESULTS: Skeletal muscle cells from 6-8 week old Sprague-Dawley rats were treated with SNAP or GSNO (25 ng/ml) in the presence or absence of glucose (25 mM) and insulin (100 nM). Cellular insulin receptor-beta levels and tyrosine phosphorylation in IRS-1 were significantly reduced, while serine phosphorylation in IRS-1 was significantly increased in these cells, when compared to the insulin-stimulated control. Reversal to near normal levels was achieved using the NO scavenger, 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl 3-oxide (carboxy-PTIO). CONCLUSION: These data suggest that NO is a potent modulator of insulin-mediated signal transduction and may play a significant role in the pathogenesis of type 2 diabetes mellitus.


Assuntos
Insulina/farmacologia , Músculo Esquelético/metabolismo , Doadores de Óxido Nítrico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Diabetes Mellitus Tipo 2/etiologia , Proteínas Substratos do Receptor de Insulina , Óxido Nítrico/farmacologia , Fosfoproteínas/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Receptor de Insulina/análise
11.
J Biomed Sci ; 13(4): 561-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16470420

RESUMO

Accumulative evidence has supported the role of nitric oxide (NO) in a variety of normal physiological functions as well as many pathological conditions. In this study, we examined the possible diabetogenicity of NO by measuring the expression of the insulin receptor substrate (IRS)-1 in rat hepatocytes and skeletal myocytes. IRS-1 is important in the insulin-mediated signal transduction pathway in both liver and skeletal muscle. Exogenous NO donated by S-nitroso-N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GSNO) resulted in significant reduction in levels of IRS-1 in both cells, when compared to the insulin-stimulated control (p<0.001). Reversal to near normal levels was achieved using the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (carboxy-PTIO). SNAP was the more potent drug, and the skeletal myocytes were the more sensitive cells to the inhibitory effects of NO released from the drugs. These results provide further evidence that exogenous NO is a potent modulator of insulin-mediated signal transduction and may play a significant role in the pathogenesis of type 2 diabetes mellitus.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/análogos & derivados , Hepatócitos/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Óxido Nítrico/farmacologia , Nitrocompostos/farmacologia , Penicilamina/análogos & derivados , Fosfoproteínas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Benzoatos/farmacologia , Glutationa/farmacologia , Imidazóis/farmacologia , Immunoblotting , Proteínas Substratos do Receptor de Insulina , Penicilamina/farmacologia , Fosfoproteínas/antagonistas & inibidores , Ratos , Fatores de Tempo
12.
Med Sci Monit ; 12(1): BR28-35, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16369460

RESUMO

BACKGROUND: The role of nitric oxide (NO) in the modulation of basal and insulin-stimulated glucose uptake remains controversial. The aim of this study was to investigate the role of NO released from its donors, S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylpenicillamine (SNAP), on glucose uptake in skeletal muscle of normoglyceamic and type 2 diabetic rats. MATERIAL/METHODS: Skeletal muscle strips of type 2 diabetic and normoglycaemic Sprague-Dawley rats were incubated with or without various concentrations (200 microM, 500 microM, 1000 microM, 10 mM & 20 mM) of SNAP or GSNO in the presence or absence of insulin (100 nM or 10 microM). The associated radioactivity was determined by liquid scintillation counting in a Beckman LS6000 scintillation counter programmed for dual-channel counting. RESULTS: SNAP and GSNO at 1000 microM significantly elevated basal and insulin-stimulated 2-deoxyglucose uptake (P<0.05) in normoglycaemic and diabetic rats. Millimolar concentrations (10 & 20 mM) of GSNO and SNAP significantly decreased basal and insulin-stimulated glucose uptake in skeletal muscle strips of normoglycaemic and type 2 diabetic rats in a concentration-dependent manner (P<0.05). The inhibition of insulin-stimulated glucose uptake was greater in the diabetic rats using both NO donors compared with normoglycaemic rats (P<0.05). CONCLUSIONS: The stimulatory effect of micromolar concentrations of GSNO and SNAP enhances basal and insulin-stimulated glucose uptake in normoglycaemic and type 2 diabetic rats, however higher concentrations elicited an inhibitory effect in normoglycaemic and diabetic rats. This highlights the NO-glucose uptake mechanism as a possible potential therapeutic target in the treatment of type 2 diabetes.


Assuntos
Diabetes Mellitus Experimental , Glucose/metabolismo , Músculo Esquelético/metabolismo , Óxido Nítrico/metabolismo , Animais , Glicemia/metabolismo , Feminino , Técnicas In Vitro , Insulina/metabolismo , Masculino , Doadores de Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , S-Nitroso-N-Acetilpenicilamina/metabolismo , S-Nitrosoglutationa/metabolismo
14.
Mol Cell Biochem ; 263(1-2): 29-34, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15524165

RESUMO

Nitric oxide (NO) is an important bioactive signaling molecule that mediates a variety of normal physiological functions, which, if altered, could contribute to the genesis of many pathological conditions, including diabetes. In this study, we examined the possible diabetogenicity of NO by noting differences in the cellular binding of insulin in dogs treated with the NO donor, S-nitrosoglutathione (GSNO) compared to captopril-treated controls. GSNO administration resulted in an abnormality in glucose metabolism which was attributed to decreased binding of insulin to its receptor on the cell membrane of mononuclear leucocytes, 11.60 +/- 0.60% in GSNO-treated dogs compared with 18.10 +/- 1.90% in captopril-treated control (p < 0.05). The decreased insulin binding was attributed to decreased insulin receptor sites per cell, 21.43 +/- 2.51 x 10(4) in GSNO-treated dogs compared with 26.60 +/- 1.57 x 10(4) in captopril-treated controls (p < 0.05). Average affinity analysis of the binding data demonstrated that this decrease in insulin binding was also due to a decrease in average affinity of the receptor on mononuclear leucocytes for insulin. This was evident by a decrease in empty and filled site affinities in GSNO-treated dogs compared with that of captopril-treated dogs (p < 0.05). It appears that GSNO is exerting its effect by decreasing the number of insulin receptor sites and/or decreasing the average receptor affinity. These results provide evidence for a novel role of NO as a modulator of insulin binding and the involvement of NO in the aetiology of diabetes mellitus.


Assuntos
Glucose/metabolismo , Óxido Nítrico/metabolismo , Animais , Ligação Competitiva , Captopril/farmacologia , Membrana Celular/metabolismo , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Cães , Feminino , Técnicas In Vitro , Insulina/metabolismo , Cinética , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Doadores de Óxido Nítrico/farmacologia , Receptor de Insulina/metabolismo , S-Nitrosoglutationa/farmacologia
15.
Phytother Res ; 18(1): 95-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14750210

RESUMO

Capsicum frutescens has been used to treat diabetes mellitus by traditional healers in Jamaica. Purification experiments employing thin layer chromatography (TLC) and high performance liquid chromatography led to the extraction of the active principle, capsaicin. Purified capsaicin caused a decrease in blood glucose levels to 4.91 +/- 0.52 (n = 6) mmol/dL versus 6.40 +/- 0.13 mmol/dL (n = 6) for the control (p < 0.05) at 2.5 h in an OGTT in dogs. There was a concomitant elevation in plasma insulin levels (p < 0.05). In conclusion, it can be stated that capsaicin is the major constituent of Capsicum frutescens that is responsible for the hypoglycaemic episodes seen in the dogs. It is also apparent that the latter is mediated by insulin release.


Assuntos
Capsaicina/farmacologia , Capsicum , Hipoglicemiantes/farmacologia , Fitoterapia , Animais , Glicemia/efeitos dos fármacos , Capsaicina/administração & dosagem , Capsaicina/química , Capsaicina/uso terapêutico , Cromatografia , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Experimental/prevenção & controle , Modelos Animais de Doenças , Cães , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
16.
Mol Cell Biochem ; 263(1): 29-34, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27520663

RESUMO

Nitric oxide (NO) is an important bioactive signaling molecule that mediates a variety of normal physiological functions, which, if altered, could contribute to the genesis of many pathological conditions, including diabetes. In this study, we examined the possible diabetogenicity of NO by noting differences in the cellular binding of insulin in dogs treated with the NO donor, S-nitrosoglutathione (GSNO) compared to captopril-treated controls. GSNO administration resulted in an abnormality in glucose metabolism which was attributed to decreased binding of insulin to its receptor on the cell membrane of mononuclear leucocytes, 11.60 ± 0.60% in GSNO-treated dogs compared with 18.10 ± 1.90% in captopril-treated control (p < 0.05). The decreased insulin binding was attributed to decreased insulin receptor sites per cell, 21.43 ± 2.51 × 10(4) in GSNO-treated dogs compared with 26.60 ± 1.57 × 10(4) in captopril-treated controls (p < 0.05). Average affinity analysis of the binding data demonstrated that this decrease in insulin binding was also due to a decrease in average affinity of the receptor on mononuclear leucocytes for insulin. This was evident by a decrease in empty and filled site affinities in GSNO-treated dogs compared with that of captopril-treated dogs (p < 0.05). It appears that GSNO is exerting its effect by decreasing the number of insulin receptor sites and/or decreasing the average receptor affinity. These results provide evidence for a novel role of NO as a modulator of insulin binding and the involvement of NO in the aetiology of diabetes mellitus. (Mol Cell Biochem 263: 29-34, 2004).

17.
BMC Pharmacol ; 2: 18, 2002 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-12230634

RESUMO

BACKGROUND: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetlypenicillamine (SNAP) are two of the most common sources of nitric oxide (NO) in the biomedical field. Vitamin C has been known to accelerate the decomposition of GSNO and SNAP increasing the release and availability of NO which is cytotoxic at non-physiological concentrations. The study investigates any potential detrimental effect of vitamin C and GSNO, vitamin C and SNAP on glucose metabolism in normotensive and normoglycemic dogs. RESULTS: The results showed that administration of vitamin C (50 mg/kg) and GSNO (35 mg/kg & 50 mg/kg), or vitamin C (50 mg/kg) and SNAP (10 mg/kg) to overnight fasted dogs resulted in significant elevation of the blood glucose levels, attaining maximum level at the 2.0 or 2.5 h time point postprandially. The elevated blood glucose levels were due to significant reduction in plasma insulin levels in the dogs treated with vitamin C and GSNO, or vitamin C and SNAP (P < 0.05). The decreased insulin response was associated with significant elevation of nitric oxide produced from GSNO and SNAP co-administered with vitamin C, as assessed by plasma nitrate/nitrite levels. CONCLUSIONS: The results indicate that enhanced NO release by vitamin C affects postprandial blood glucose and plasma insulin levels and the reduced glucose tolerance is mainly due to impaired insulin release. The clinical relevance of the findings of this study suggest that hypertensive diabetic patients treated with GSNO or SNAP, who are on vitamin C supplements may be more predisposed to further decrease in their glycemic control.


Assuntos
Ácido Ascórbico/farmacologia , Glicemia/efeitos dos fármacos , Hiperglicemia/induzido quimicamente , S-Nitroso-N-Acetilpenicilamina/toxicidade , S-Nitrosoglutationa/toxicidade , Vasodilatadores/toxicidade , Animais , Cães , Sinergismo Farmacológico , Feminino , Masculino , Modelos Animais
18.
J Natl Med Assoc ; 94(7): 561-5, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12126281

RESUMO

This study was designed to investigate the prevalence of hypertension in Jamaica. Jamaica has an area of 4,411 square miles and is divided into 14 parishes. The visited districts were randomly selected. The sample population was selected based upon a two-stage stratified random sampling design. Each dwelling in the "Sampling Universe" had an equal probability of being selected. The survey team spent a week in the districts in each parish selected. Employing the Statistical Institute of Jamaica's (STATIN) two-stage stratified random sampling design, preselected house-holds were visited. Non-response was documented and considered in the final analysis. Only individuals 15 years and older were allowed to participate in the study. The 2,064 subjects who participated were the basis for estimates of hypertension. Following logistic regression analysis, the main risk factors for hypertension are being female, advancing age, obesity, having diabetes and having a family history of hypertension. Jamaica has a point prevalence of hypertension of 30.8% in the 15-and-over age group. These findings would greatly assist in formulating policies to deal with this scourge of society.


Assuntos
Hipertensão/epidemiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Jamaica/epidemiologia , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco
19.
BMC Biochem ; 3: 1, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11825341

RESUMO

BACKGROUND: Nitric oxide (NO) and oxygen free-radicals play an important part in the destruction of beta-cells in auto- immune diabetes although the precise mechanism of interaction is still not known. This study was designed to examine any possible diabetogenic effect of NO by investigating any differences in cellular binding of insulin to its receptor on the cell membranes of erythrocytes and mononuclear leucocytes of dogs treated with the NO donor, S-nitroso-N-acetylpenicillamine (SNAP) and controls treated with captopril. RESULTS: The result obtained showed decreased binding of insulin to its receptor on the cell membranes of erythrocytes and mononuclear leucocytes. Mononuclear leucocytes from SNAP-treated dogs had decreased ability to bind insulin (16.30 +/- 1.24 %) when compared to mononuclear leucocytes from captopril-treated controls (20.30 +/- 1.93 %). Similar results were obtained for erythrocytes from dogs treated with SNAP (27.20 +/- 1.33 %) compared with dogs treated with captopril (34.70 +/- 3.58 %). Scatchard analysis demonstrated that this decrease in insulin binding was accounted for by a decrease in insulin receptor sites per cell, with mononuclear leucocytes of SNAP-treated dogs having 55 % less insulin receptor sites per cell compared with those of captopril-treated controls (P < 0.05). Average affinity and kinetic analysis revealed a 35 % decrease in the average receptor affinity, with mononuclear leucocytes from captopril-treated controls having an empty site affinity of 12.36 +/- 1.12 x 10(-8) M(-1) compared with 9.64 +/- 0.11 x 10(-8) M(-1) in SNAP-treated dogs (P < 0.05). CONCLUSION: These results suggest that acute alteration of the insulin receptor on the membranes of mononuclear leucocytes and erythrocytes occurred in dogs treated with S-nitroso-N-acetylpenicillamine. These findings suggest the first evidence of the novel role of NO as a modulator of insulin binding and the involvement of NO in the aetiology of diabetes mellitus.


Assuntos
Insulina/metabolismo , Doadores de Óxido Nítrico/farmacologia , Receptor de Insulina/metabolismo , S-Nitroso-N-Acetilpenicilamina/farmacologia , Animais , Ligação Competitiva , Captopril/farmacologia , Membrana Celular/metabolismo , Cães , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Cinética , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino
20.
West Indian med. j ; 50(suppl. 1): 55, Mar. 1-4, 2001.
Artigo em Inglês | MedCarib | ID: med-420

RESUMO

The nitric oxide donor S-nitrosoglutathione (GSNO) has been used to prevent platelet activation in patients with severe pre-eclampsia. The study assesses the chronic administration of GSNO on glucose metabolism in the dog animal model. GSNO (10 mg/kg) was administered intravenously for 14 days and the blood glucose concentration was determined by the glucose oxidase method. Oral glucose tolerance tests revealed an impaired glucose tolerance in the GSNO-treated dogs as reflected by elevated postprandial blood glucose concentrations at the 1.0 hour to 2.5 hour time interval (p < 0.05). The elevated blood glucose concentration was associated with a statistically significant decrease in plasma insulin concentration. The plasma insulin concentration at 1.0 hour in captopril-treated controls was 41.00 uIU/ml compared with 27.33 uIU/ml in GSNO-treated dogs (p < 0.05). In contrast, the plasma glucagon concentration was enhanced by the chronic adminstration of GSNO, as confirmed by a concentration of 75.00 ñ 6.06 pg/ml in GSNO-treated dogs compared with 49.50 ñ 4.64 pg/ml in captopril-treated controls at the 1.0 hour time interval. Linear regression analysis of the data revealed a highly significant and positive correlation between the blood glucose concentration and the plasma glucagon concentration (r = 0.739, p < 0.01). Similarly, a positive correlation existed between the blood glucose concentration and the plasma insulin concentration (r = 0.513, p = 0.307). We conclude that chronic in vivo adminstration of GSNO impairs the parameters of carbohydrate metabolism. Patients who are on protracted treatment with GSNO could be risk for the development of diabetes mellitus.(Au)


Assuntos
Cães , 21003 , Técnicas In Vitro , Ativação Plaquetária , Doadores de Óxido Nítrico/administração & dosagem , Glucose/metabolismo , Teste de Tolerância a Glucose , Cães/metabolismo , Avaliação de Medicamentos , Carboidratos/metabolismo
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