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1.
PLoS Med ; 17(10): e1003367, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33007052

RESUMO

BACKGROUND: Diabetes outcomes are influenced by host factors, settings, and care processes. We examined the association of data-driven integrated care assisted by information and communications technology (ICT) with clinical outcomes in type 2 diabetes in public and private healthcare settings. METHODS AND FINDINGS: The web-based Joint Asia Diabetes Evaluation (JADE) platform provides a protocol to guide data collection for issuing a personalized JADE report including risk categories (1-4, low-high), 5-year probabilities of cardiovascular-renal events, and trends and targets of 4 risk factors with tailored decision support. The JADE program is a prospective cohort study implemented in a naturalistic environment where patients underwent nurse-led structured evaluation (blood/urine/eye/feet) in public and private outpatient clinics and diabetes centers in Hong Kong. We retrospectively analyzed the data of 16,624 Han Chinese patients with type 2 diabetes who were enrolled in 2007-2015. In the public setting, the non-JADE group (n = 3,587) underwent structured evaluation for risk factors and complications only, while the JADE (n = 9,601) group received a JADE report with group empowerment by nurses. In a community-based, nurse-led, university-affiliated diabetes center (UDC), the JADE-Personalized (JADE-P) group (n = 3,436) received a JADE report, personalized empowerment, and annual telephone reminder for reevaluation and engagement. The primary composite outcome was time to the first occurrence of cardiovascular-renal diseases, all-site cancer, and/or death, based on hospitalization data censored on 30 June 2017. During 94,311 person-years of follow-up in 2007-2017, 7,779 primary events occurred. Compared with the JADE group (136.22 cases per 1,000 patient-years [95% CI 132.35-140.18]), the non-JADE group had higher (145.32 [95% CI 138.68-152.20]; P = 0.020) while the JADE-P group had lower event rates (70.94 [95% CI 67.12-74.91]; P < 0.001). The adjusted hazard ratios (aHRs) for the primary composite outcome were 1.22 (95% CI 1.15-1.30) and 0.70 (95% CI 0.66-0.75), respectively, independent of risk profiles, education levels, drug usage, self-care, and comorbidities at baseline. We reported consistent results in propensity-score-matched analyses and after accounting for loss to follow-up. Potential limitations include its nonrandomized design that precludes causal inference, residual confounding, and participation bias. CONCLUSIONS: ICT-assisted integrated care was associated with a reduction in clinical events, including death in type 2 diabetes in public and private healthcare settings.


Assuntos
Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Adulto , Estudos de Coortes , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Autocuidado/métodos , Resultado do Tratamento
2.
PLoS One ; 8(10): e77516, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24143239

RESUMO

BACKGROUND: Insulin-like growth factor binding protein-3 (IGFBP-3) is a multifunctional molecule which is closely related to cell growth, apoptosis, angiogenesis, metabolism and senescence. It combines with insulin-like growth factor-I (IGF-I) to form a complex (IGF-I/IGFBP-3) that can treat growth hormone insensitivity syndrome (GHIS) and reduce insulin requirement in patients with diabetes. IGFBP-3 alone has been shown to have anti-proliferation effect on numerous cancer cells. METHODOLOGY/PRINCIPAL FINDINGS: We reported here an expression method to produce functional recombinant human IGFBP-3 (rhIGFBP-3) in transgenic rice grains. Protein sorting sequences, signal peptide and endoplasmic reticulum retention tetrapeptide (KDEL) were included in constructs for enhancing rhIGFBP-3 expression. Western blot analysis showed that only the constructs with signal peptide were successfully expressed in transgenic rice grains. Both rhIGFBP-3 proteins, with or without KDEL sorting sequence inhibited the growth of MCF-7 human breast cancer cells (65.76 ± 1.72% vs 45.00 ± 0.86%, p < 0.05; 50.84 ± 1.97% vs 45.00 ± 0.86%, p < 0.01 respectively) and HT-29 colon cancer cells (65.14 ± 3.84% vs 18.01 ± 13.81%, p < 0.05 and 54.7 ± 9.44% vs 18.01 ± 13.81%, p < 0.05 respectively) when compared with wild type rice. CONCLUSION/SIGNIFICANCE: These findings demonstrated the feasibility of producing biological active rhIGFBP-3 in rice using a transgenic approach, which will definitely encourage more research on the therapeutic use of hIGFBP-3 in future.


Assuntos
Neoplasias da Mama/patologia , Neoplasias do Colo/patologia , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Oryza/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Glicosilação , Células HT29 , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Células MCF-7 , Plantas Geneticamente Modificadas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
3.
Pancreas ; 42(7): 1129-37, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24005233

RESUMO

OBJECTIVE: Islet amyloidosis and arteriosclerosis are histopathological hallmarks in type 2 diabetes. Apolipoprotein E (ApoE) is a common component of amyloidosis. ApoE [Latin Small Letter Open E]4 allele is associated with arteriosclerosis and cerebral amyloidosis in Alzheimer disease. We examined the correlations of ApoE polymorphisms with islet amyloidosis in type 2 diabetes. METHODS: Genomic DNA samples were obtained from 117 autopsy cases with type 2 diabetes and 209 nondiabetic cases. ApoE genotypes and amylin gene mutations were determined by polymerase chain reaction-ligase detection reaction analysis. Islet amyloidosis and arteriosclerosis were evaluated by staining of thioflavin T, amylin, ApoE, and amyloid P component. RESULTS: In the diabetic group, 33.3% in group [Latin Small Letter Open E]2 ([Latin Small Letter Open E]2[Latin Small Letter Open E]2, [Latin Small Letter Open E]2[Latin Small Letter Open E]3), 23.6% in group [Latin Small Letter Open E]3 ([Latin Small Letter Open E]3[Latin Small Letter Open E]3), and 62.5% in group [Latin Small Letter Open E]4 ([Latin Small Letter Open E]4[Latin Small Letter Open E]4, [Latin Small Letter Open E]3[Latin Small Letter Open E]4) had islet amyloidosis. After adjustment for confounders, group [Latin Small Letter Open E]4 had an odds ratio of 7.0 (95% confidence interval, 1.3-38.0; P = 0.023) in having islet amyloidosis compared to group [Latin Small Letter Open E]3. Diabetic cases with islet amyloidosis had more severe arteriosclerosis (P = 0.0111), arteriolar hyalinosis (P = 0.0369), and interstitial fibrosis (P = 0.0188) than those without amyloidosis. Immunoreactivity of both ApoE and amyloid P component was detected in islet amyloid deposits and arteriosclerotic lesions. CONCLUSIONS: In type 2 diabetes, islet amyloidosis and arteriosclerosis share common pathophysiological features with ApoE [Latin Small Letter Open E]4 as a probable linking factor.


Assuntos
Amiloidose/complicações , Amiloidose/genética , Apolipoproteínas E/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Pancreatopatias/complicações , Pancreatopatias/genética , Polimorfismo Genético , Idoso , Idoso de 80 Anos ou mais , Amiloidose/patologia , Apolipoproteínas E/metabolismo , Arteriosclerose/complicações , Arteriosclerose/genética , Arteriosclerose/patologia , Povo Asiático/genética , Estudos de Casos e Controles , China , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Ilhotas Pancreáticas/patologia , Masculino , Pessoa de Meia-Idade , Pancreatopatias/patologia , Componente Amiloide P Sérico/metabolismo
4.
Curr Cardiovasc Risk Rep ; 5(3): 230-239, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21654912

RESUMO

Diabetes is a complex disease characterized by chronic hyperglycemia and multiple phenotypes. In 1995, we used a doctor-nurse-clerk team and structured protocol to establish the Hong Kong Diabetes Registry in a quality improvement program. By 2009, we had accrued 2616 clinical events in 9588 Chinese type 2 diabetic patients with a follow-up duration of 6 years. The detailed phenotypes at enrollment and follow-up medications have allowed us to develop a series of risk equations to predict multiple endpoints with high sensitivity and specificity. In this prospective database, we were able to validate findings from clinical trials in real practice, confirm close links between cardiovascular and renal disease, and demonstrate the emerging importance of cancer as a leading cause of death. In addition to serving as a tool for risk stratification and quality assurance, ongoing data analysis of the registry also reveals secular changes in disease patterns and identifies unmet needs.

6.
Cancer ; 117(4): 862-71, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20939014

RESUMO

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) have increased cancer risks. The authors reported nonlinear associations of cancer with triglyceride and other lipids in T2DM. Crosstalk between lipid metabolism and the renin-angiotensin system may increase cancer risk via activation of insulin-like growth factor-1 pathway in T2DM. In this analysis, the authors explored associations of cancer risk with high/low triglyceride in T2DM and possible modifying effects of statins on this risk association, if any. METHODS: A consecutive cohort of 5166 Chinese patients with T2DM, free of cancer at enrollment and not using statins at or before enrollment, was analyzed using Cox models. Biological interactions were estimated using relative excess risk because of interaction, attributable proportion because of interaction, and synergy index. Relative excess risk because of interaction > 0, attributable proportion because of interaction > 0, or synergy index > 1 indicates biological interaction. RESULTS: During 5.25 years of follow-up (median), 4.7% (n = 243) patients developed cancer. Triglyceride < 1.70 mmol/L was associated with increased cancer risk in the entire cohort and in statin nonusers, but not in statin users. Patients with triglyceride < 1.70 mmol/L plus nonuse of statins during follow-up had 2.74-fold increased cancer risk compared with their counterparts with either triglyceride ≥ 1.70 mmol/L or use of statins or both. There was significant interaction between triglyceride < 1.70 mmol/L and nonuse of statins (relative excess risk because of interaction, 0.99; 95% confidence interval [CI], 0.07-1.90 and attributable proportion because of interaction, 0.36; 95% CI, 0.02-0.70). CONCLUSIONS: In Chinese T2DM patients, triglyceride < 1.70 mmol/L might be associated with increased cancer risk, which was attenuated in the presence of use of statins.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias/complicações , Triglicerídeos/sangue , Idoso , Povo Asiático , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Sistema de Registros , Risco
7.
Diabetes Res Clin Pract ; 90(3): 343-51, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20889221

RESUMO

BACKGROUND: Hyperglycaemia is a risk factor for cancer and some sulphonylureas have anti-oxidant properties. This study examined associations between use of sulphonylureas and cancer. METHODS: A consecutive cohort of 6103 Hong Kong Chinese patients with T2DM, free of cancer, was analysed using Cox models. Sulphonylurea usage was defined as use of the drugs at or within 2.5 years before enrolment and/or during follow-up periods. We adjusted for identified risk factors of cancer, use of other drugs, non-linear associations of lipids with cancer and probabilities of use of these drugs at different times and doses where appropriate. RESULTS: During a median of 4.91 years of follow-up, 271 developed cancer. Glibenclamide, gliclazide and glipizide were ever used in 32.5% (n = 1983), 47.8% (n = 2920) and 13.5% (n = 823). After adjustment for covariates, use of gliclazide and glibenclamide was associated with reduced cancer risk in a dose-dependent manner. In addition, there were interactions between metformin and glibenclamide/glipizide use towards lower adjusted cancer risks. CONCLUSIONS: In T2DM, use of glibenclamide and gliclazide may be associated with reduced cancer risk.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Neoplasias/etiologia , Compostos de Sulfonilureia/uso terapêutico , Idoso , Povo Asiático , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Feminino , Gliclazida/uso terapêutico , Glipizida/uso terapêutico , Glibureto/uso terapêutico , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sistema de Registros , Fatores de Risco
8.
Cell Signal ; 22(10): 1513-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20570724

RESUMO

Insulin and AMP-activated protein kinase (AMPK) signal pathways are involved in the regulation of glucose uptake. The integration of signals between these two pathways to maintain glucose homeostasis remains elusive. In this work, stimulation of insulin and berberine conferred a glucose uptake or surface glucose transporter 4 (GLUT4) translocation that was less than simple summation of their effects in insulin-sensitive muscle cells. Using specific inhibitors to key kinases of both pathways and PKCzeta small interference RNA, protein kinase C zeta (PKCzeta) was found to regulate insulin-stimulated protein kinase B (PKB) activation and inhibit AMPK activity on dorsal cell surface. In the presence of berberine, PKCzeta controlled AMPK activation and AMPK blocked PKB activity in perinuclear region. The inhibition effect of PKCzeta on AMPK activation or the arrestment of PKB activity by AMPK still existed in basal condition. These results suggest that there is antagonistic regulation between insulin and AMPK signal pathways, which is mediated by the switch roles of PKCzeta.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Insulina/farmacologia , Fibras Musculares Esqueléticas/enzimologia , Proteína Quinase C/fisiologia , Transdução de Sinais , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Berberina/farmacologia , Transporte Biológico , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
9.
Pancreas ; 39(6): 843-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20467341

RESUMO

OBJECTIVES: The aim of this study was to examine correlations of the islet-specific microRNA-375 expression to islet amyloid formation and pancreatic islet damage in human type 2 diabetes. METHODS: Autopsy pancreas samples from 40 type 2 diabetic and 15 nondiabetic patients were used to detect microRNA-375 expression using real-time quantitative polymerase chain reaction. Serial paraffin sections of the corresponding type 2 diabetic and nondiabetic cases were stained by immunofluorescence to evaluate for amylin expression, amyloid formation, and proportions of alpha and beta cells. RESULTS: Pancreatic microRNA-375 expression was increased in type 2 diabetic patients comparing with the nondiabetic patients (median, 4.02 for the diabetic patients vs 0.92 for the nondiabetic patients; P = 0.0001). The median was 6.14 for the diabetic patients with islet amyloid and 3.51 for islet amyloid-free diabetic patients. The expression level of microRNA-375 correlated positively with the frequency and the severity of islet amyloid formation and negatively with proportions of islet beta-cells and amylin-positive area, and islet mitochondria density. CONCLUSIONS: Up-regulated microRNA-375 is associated with type 2 diabetes and pancreatic islet amyloid formation and beta-cell deficit. microRNA-375 may serve as a biomarker for known and novel pathways in the pathogenesis of type 2 diabetes related to islet amyloid deposition and beta-cell dysfunction.


Assuntos
Diabetes Mellitus Tipo 2/genética , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloide/metabolismo , Autopsia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/fisiopatologia , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
10.
Diabetes ; 59(5): 1254-60, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20185812

RESUMO

OBJECTIVE Insulin has mitogenic effects, although hyperglycemia may be a risk factor for cancer in type 2 diabetes. It remains uncertain whether use of insulin increases cancer risk because of its effect on cell growth and proliferation or decreases cancer risk because of its glucose-lowering effect. RESEARCH DESIGN AND METHODS A 1:2-matched new insulin user cohort on age (+/-3 years), smoking status, and likelihood of initiating insulin therapy (+/-0.05) was selected from a cohort of 4,623 Chinese patients with type 2 diabetes, free of cancer, and naive to insulin at enrollment. Stratified Cox regression analysis on the matched pairs was used to obtain hazard ratios (HRs) of insulin therapy and A1C for cancer risk. A structured adjustment scheme was used to adjust for covariates. RESULTS Of 973 new insulin users, 971 had matched nonusers (n = 1935). The cancer incidence in insulin nonusers was much higher than that in insulin users (49.2 vs. 10.2, per 1,000 person-years, P < 0.0001). After further adjustment for all other covariates with a P value less than 0.3 and nonlinear associations with cancer, A1C was associated with an increased cancer risk (HR per percentage 1.26, 95% CI 1.03-1.55), whereas use of insulin was associated with a decreased cancer risk (HR of insulin users vs. nonusers: 0.17, 0.09-0.32). Consistent results were found in analyses including all 973 insulin users and 3,650 nonusers. CONCLUSIONS In Chinese patients with type 2 diabetes, hyperglycemia predicts cancer, whereas insulin usage was associated with a reduced cancer risk.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Insulina/efeitos adversos , Insulina/uso terapêutico , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Adulto , Idoso , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Hiperglicemia/epidemiologia , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
Am J Physiol Renal Physiol ; 298(2): F391-400, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19940035

RESUMO

The kidney is one of the major organs involved in whole-body homeostasis while chronic renal impairment usually leads to fat redistribution and hyperlipidemia. The aim of this study was to elucidate the role of tissue renal renin-angiotensin system (RAS) components, lipogenic peroxisome proliferator-activated receptor-gamma (PPARgamma), and cytokine TNF-alpha in the development of ectopic adipogenesis and lipid deposition. Adult male Sprague-Dawley rats were randomized into three groups: untreated uninephrectomized (UNX) rats, UNX rats treated with an angiotensin-converting enzyme inhibitor (ACEI), lisinopril, and sham-operated rats. All animals were euthanized at 10 mo postoperation. The untreated UNX rats showed increased protein expression of renin, angiotensinogen, PPARgamma, and the angiotensin II type 2 receptor (AT2R) but reduced protein expression of AT1R and TNF-alpha in their remnant kidneys. Immunofluorescence staining revealed increased reactivity of angiotensinogen and angiotensin I/II in renal tubular cells and adipocytes of the untreated UNX rats. ACEI treatment largely prevented these disorders in association with restored normolipidemia and normalized renal adipogenesis and lipid deposition. These findings support the notion that tissue RAS, PPARgamma, and TNF-alpha collectively play an important role in the renal adipogenesis and lipid metabolism.


Assuntos
Adipogenia/fisiologia , Rim/citologia , PPAR gama/metabolismo , Sistema Renina-Angiotensina/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adipócitos/patologia , Tecido Adiposo/patologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Hiperinsulinismo , Hiperlipidemias , Rim/metabolismo , Córtex Renal/patologia , Metabolismo dos Lipídeos/fisiologia , Lisinopril/farmacologia , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley , Células-Tronco/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores
12.
Diabetes Res Clin Pract ; 87(1): 117-25, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19932519

RESUMO

BACKGROUND: High white blood cell (WBC) predicted cancer-associated mortality and renin-angiotensin system (RAS) inhibitors have immunomodulating effects. We hypothesize that RAS inhibitors may reduce cancer risk associated with high WBC in type 2 diabetes mellitus (T2DM). METHODS: A prospective cohort of 4570 Chinese T2DM patients, free of cancer at enrolment, were analyzed. Biological interaction between WBC groups and use of RAS inhibitors was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). RERI>0, AP>0 or S>1 indicates biological interaction. RESULTS: During 4.89 years of follow-up, 205 (4.49%) patients developed cancer. WBC > or = 8.2 x 10(9) counts/L plus non-use of RAS inhibitors was associated with elevated cancer risks in multivariable models. The RERI and AP for interaction between WBC > or = 8.2 x 10(9) counts/L and non-use of RAS inhibitors were, respectively, 1.26 (95% CI: 0.22-2.31) and 0.50 (0.23-0.78). In patients with WBC > or = 8.2 x 10(9) counts/L, use of RAS inhibitors was associated with 64% (31-81%) cancer risk reduction in multivariable analysis. CONCLUSIONS: In T2DM, increased WBC predicts cancer while use of RAS inhibitors may reduce cancer risks associated with high WBC count.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Contagem de Leucócitos , Neoplasias/epidemiologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Pressão Sanguínea , Índice de Massa Corporal , Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hong Kong/epidemiologia , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Admissão do Paciente/estatística & dados numéricos , Modelos de Riscos Proporcionais , Fatores de Risco , Triglicerídeos/sangue
13.
Diabetes Care ; 32(10): 1826-32, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19592629

RESUMO

OBJECTIVE: LDL cholesterol <2.80 mmol/l was associated with increased cancer risk in type 2 diabetes. We explored the 1) interaction between low LDL cholesterol and albuminuria and 2) interaction between copresence of these two risk factors and statin use for cancer in type 2 diabetes. RESEARCH DESIGN AND METHODS: We analyzed prospective data for 3,793 Chinese type 2 diabetic patients who remained naive for statin treatment and 1,483 patients in whom statin treatment was initiated during a median follow-up period of 5.24 years. All patients were free of cancer at baseline. Biological interactions were estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (S). RERI > 0, AP > 0, or S > 1 indicates biological interaction. RESULTS: In 3,793 statin-naive type 2 diabetic patients, copresence of low LDL cholesterol and albuminuria increased cancer risk by 2.8-fold (hazard ratio 2.77 [95% CI 1.78-4.31]) with significant biological interactions (RERI 1.05 [0.04-2.06]; AP 0.38 [0.09-0.66]). In the whole cohort of 5,276 type 2 diabetic patients, there was interaction between nonuse of statins and copresence of low LDL cholesterol and albuminuria with increased cancer risk (RERI 2.87 [0.64-5.09] and AP 0.60 [0.29-0.90]). Statin nonusers with LDL cholesterol <2.80 mmol/l and albumunuria had a 4.9-fold risk of cancer compared with statin users with or without both risk factors. CONCLUSIONS: In type 2 diabetes, there was interaction between low LDL cholesterol and albuminuria with increased cancer risks. The latter was attenuated in the presence of statin treatment.


Assuntos
Albuminúria/fisiopatologia , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias/epidemiologia , Neoplasias/etiologia , Adulto , Idoso , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Risco
14.
Transgenic Res ; 18(6): 943-51, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19504171

RESUMO

Human insulin-like growth factor binding protein-3 (hIGFBP-3) is a multifunctional protein which has high affinity for insulin-like growth factor-I (IGF-I). It combines with IGF-I to form a tertiary complex in circulation, thus regulating the activity of IGF-I. Furthermore, recombinant hIGFBP-3 (rhIGFBP-3) has been found to negatively regulate cell proliferation and induce apoptosis. In this study, we have established an efficient plant bioreactor platform for mass production of rhIGFBP-3. Different expression constructs, driven by the seed-specific phaseolin promoter, were designed and transformed into tobacco plant via Agrobacterium. To enhance protein expression level, the signal peptide (SP) and the C-terminal tetrapeptide AFVY of phaseolin were used to direct rhIGFBP-3 to protein storage vacuole (PSV) in tobacco seed for stable accumulation. Western blot analysis showed that rhIGFBP-3 was successfully synthesized in transgenic tobacco seeds, with the highest protein expression of 800 mug/g dry weight. The localization of rhIGFBP-3 in PSV was also evident by confocal immunofluorescence microscopy. Our results indicated that protein sorting sequences could benefit the expression level of rhIGFBP-3 and it is feasible to use plant as "bio-factory" to produce therapeutic recombinant proteins in large quantity.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Nicotiana/genética , Genoma de Planta , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Plantas Geneticamente Modificadas/genética , Sinais Direcionadores de Proteínas , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rhizobium/genética , Nicotiana/metabolismo , Transformação Genética
15.
Diabetes ; 58(7): 1518-25, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19401427

RESUMO

OBJECTIVE: Clinical and experimental studies suggest cross-talk between lipid metabolism and the renin-angiotensin system (RAS) in atherogenesis. The aim of this study was to explore interactions between these two systems in mediating cancer risk in type 2 diabetes. RESEARCH DESIGN AND METHODS: A prospective cohort of 4,160 Chinese patients with type 2 diabetes, free of cancer at enrollment, were analyzed using Cox models. Interaction of RAS inhibitors (angiotensin I-converting enzyme inhibitors or angiotensin II receptor blockers) and statins was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (S). RERI > 0, AP > 0, or S > 1 indicates additive interaction between the two classes of drugs. Molecular mechanisms underlying these interactions were explored using a uninephrectomy (UNX) rat model with renal carcinogenesis. RESULTS: During 21,992 person-years of follow-up, 190 patients developed cancer. Use of RAS inhibitors and statins in isolation or combination during follow-up was associated with reduced risk of cancer after adjustment for covariates. The multivariable RERI and AP for the additive interaction between these drug classes for cancer were significant (0.53 [95% CI 0.20-0.87] and 2.65 [0.38-4.91], respectively). In the UNX rat model, inhibition of the RAS prevented renal cell carcinoma by normalizing hydroxymethylglutaryl-CoA reductase (HMGCR) expression and the insulin-like growth factor-1 (IGF-1) signaling pathway. CONCLUSIONS: Combined use of RAS inhibitors and statins may act synergistically to reduce cancer risk, possibly via HMGCR and IGF-1 signaling pathways in high-risk conditions such as type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Lipídeos/fisiologia , Neoplasias/complicações , Neoplasias/metabolismo , Sistema Renina-Angiotensina/fisiologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Carcinoma de Células Renais/epidemiologia , Estudos de Coortes , Modelos Animais de Doenças , Hong Kong/epidemiologia , Humanos , Pacientes Internados , Fator de Crescimento Insulin-Like I/fisiologia , Testes de Função Renal , Neoplasias Renais/epidemiologia , Lisinopril/uso terapêutico , Neoplasias/epidemiologia , Pacientes Ambulatoriais , Ratos , Ratos Sprague-Dawley , Sistema de Registros , Fatores de Risco
16.
Int J Biochem Cell Biol ; 41(7): 1526-35, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19166964

RESUMO

It is widely accepted that human islet amyloid polypeptide (hIAPP) aggregation plays an important role in the loss of insulin-producing pancreatic beta cells. hIAPP-induced cytotoxicity is mediated by generation of reactive oxygen species (ROS). Phycocyanin (PC) is a natural compound from blue-green algae that is widely used as food supplement. Currently, little is known about the effects of PC on beta cells with the presence of hIAPP. The aim of this study was to investigate the in vitro protective effects of PC on INS-1E rat insulinoma beta cells against hIAPP-induced cell death, as well as the underlying mechanisms. Our results showed that hIAPP-induced cell death with apoptotic characteristics including growth inhibition, chromatin condensation and DNA fragmentation. However, cytotoxicity of hIAPP was significantly attenuated by co-incubation of the cells with PC. The results of Western blotting showed that activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP) in hIAPP-treated cells was blocked by PC. Moreover, PC significantly prevented the hIAPP-induced overproduction of intracellular ROS and malondialdehyde (MDA), as well as changes in activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) enzymes. Furthermore, hIAPP triggered the activation of mitogen-activated protein kinases (MAPKs), and these effects were effectively suppressed by PC. Taken together, our results suggest that PC protects INS-1E pancreatic beta cells against hIAPP-induced apoptotic cell death through attenuating oxidative stress and modulating c-Jun N-terminal kinase (JNK) and p38 pathways.


Assuntos
Amiloide/farmacologia , Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Células Secretoras de Insulina/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ficocianina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Antioxidantes/metabolismo , Caspase 3/metabolismo , Ativação Enzimática/efeitos dos fármacos , Radicais Livres/metabolismo , Humanos , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos
17.
Transl Res ; 153(1): 24-32, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19100955

RESUMO

The amyloid hypothesis of type 2 diabetes mellitus postulates that elevated levels of normally expressed monomeric proteins of human islet amyloid polypeptide (hIAPP) trigger oligomerization that independently causes fibril formation and disease progression. The aim of this study was to demonstrate the existence of amyloid oligomers in human pancreatic islets. Human pancreas tissues were obtained at autopsy of 8 nondiabetic control subjects (mean age = 75.8 +/- 11.7 years, 4 males), 8 type 2 diabetic cases without islet amyloid (mean age = 78.8 +/- 8.5 years, 4 males), and 8 type 2 diabetic patients with islet amyloid (mean age = 73.7 +/- 14.2 years, 4 males). Several markers for insulin, IAPP, amyloid fibrils (thioflavin T), and apoptosis (cleaved caspase-3) were used in combination with an oligomer-specific antibody. Two distinct forms of oligomers were found in pancreatic islets. Small spherical puncta were found in approximately 3% to 20% of the islet cells of nondiabetic subjects, and large curvilinear structures as extracellular oligomers were identified frequently in diabetic islets. Large oligomers were spatially localized adjacent to amyloid fibrils and were associated with apoptosis. This report demonstrates the presence of 2 morphologic classes of amyloid oligomers in human pancreatic islets. The observations warrant function studies to investigate the clinical implications of the amyloid oligomerization in the pathogenesis of type 2 diabetes.


Assuntos
Amiloide/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ilhotas Pancreáticas/metabolismo , Idoso , Apoptose , Benzotiazóis , Biomarcadores/metabolismo , Western Blotting , Caspase 3/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Ilhotas Pancreáticas/patologia , Masculino , Multimerização Proteica , Tiazóis/metabolismo
18.
Pancreas ; 37(3): e68-73, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18815541

RESUMO

OBJECTIVES: Type 2 diabetes mellitus is characterized histopathologically by islet amyloid deposits formed from islet amyloid polypeptide. The aim of this study was to investigate sex difference in islet amyloid of type 2 diabetic patients. METHODS: Pancreas specimens were collected from 235 autopsies with type 2 diabetes mellitus. Islet amyloid was identified with Congo red stain. The load of islet amyloid deposits was assessed by prevalence (percentage of cases with islet amyloid deposits), frequency (percentage of islets containing amyloid deposits), and severity (percentage of islet area occupied by amyloid deposits). RESULTS: Women (n = 80) and men (n = 155) had similar age of death, duration of diabetes, body mass index, and hemoglobin (Hb)A1c level. Islet amyloid was found in 30.0% of the women and in 44.5% of the men (P = 0.035). None of 9 women younger than 50 years had islet amyloid. Frequency of amyloid-affected islets was 31.5% +/- 13.1% in women and 41.1% +/- 14.3% in men (P = 0.008). Severity of amyloid-affected islet area was 29.0% +/- 12.5% in women and 38.5% +/- 14.6% in men (P = 0.007). CONCLUSIONS: Sex is a determinant of the development of islet amyloid in type 2 diabetes mellitus. This sex difference in islet amyloid may be related to a potential benefit of female sex hormones.


Assuntos
Amiloide/análise , Diabetes Mellitus Tipo 2/metabolismo , Ilhotas Pancreáticas/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Ilhotas Pancreáticas/patologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores Sexuais
19.
CMAJ ; 179(5): 427-37, 2008 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-18725615

RESUMO

BACKGROUND: The risk association between low-density lipoprotein (LDL) cholesterol and cancer remains controversial and largely unexplored for people not receiving statin therapy. METHODS: We examined the risk association between LDL cholesterol and cancer among patients with type 2 diabetes mellitus who were free of cancer at enrolment and whose statin use was known. We considered a variety of nonlinear relationships in our analysis. RESULTS: During a median follow-up period of 4.90 years, cancer developed in 270 (4.4%) of 6107 patients. Among the 3800 patients who did not receive statin therapy, the risk association between LDL cholesterol and cancer was represented by a V-shaped curve. Compared with patients whose LDL cholesterol was at least 2.80 mmol/L but less than 3.80 mmol/L, the risk of cancer, death from any cause or the composite outcome of cancer or death was greater among those with an LDL cholesterol level of less than 2.80 mmol/L (hazard ratio for cancer 1.74, 95% confidence interval [CI] 1.20-2.52) and those with an LDL cholesterol level of 3.80 mmol/L or greater (hazard ratio for cancer 1.87, 95% CI 1.29-2.71). Using 3.8 mmol/L as a reference point, we found that the hazard ratio for cancer for every millimole per litre absolute change in LDL cholesterol was 1.54 (95% CI 1.19-1.99) among patients not using statins; the hazard ratio was reduced to 1.24 (1.01-1.53) for the entire sample (statin users and those not using statins). These associations persisted after adjustment for covariates and exclusion of patients with less than 2.5 years of follow-up. INTERPRETATION: Among patients with type 2 diabetes, the association between LDL cholesterol and cancer was V-shaped, whereby both low and high levels of LDL cholesterol were associated with elevated risk of cancer.


Assuntos
LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/complicações , Hipercolesterolemia/complicações , Neoplasias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
20.
Endocr Relat Cancer ; 15(2): 597-607, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18509007

RESUMO

Type 2 diabetic patients have increased cancer risk. We developed and validated an all-site cancer risk score in a prospective cohort of 7374 Chinese type 2 diabetic patients free of known history of cancer at enrolment, using split-half validation. Spline Cox model was used to detect common risk factors of cancer and to guide linear transformation of non-linear risk factors. After a median follow-up period of 5.45 years, 365 patients (4.95%) developed cancer. Body mass index (BMI; <24.0 or > or =27.6 kg/m2), triglyceride (> or =0.81 to <1.41 mmol/l), high-density lipoprotein cholesterol (<0.9 or > or =1.8 mmol/l), total cholesterol (<4.3 mmol/l) and white blood cell (WBC) count (<5.8x10(9) count per litre) were associated with increased cancer risks and exhibited non-linear relationships. We further linear transformed these terms for selection using backward Cox regression (P<0.05 for stay) in the training dataset. In the test dataset, calibration was checked using Hosmer-Lemeshow test and discrimination checked using area under receiver operating characteristic curve. In addition to age and current smoking, only linear-transformed total cholesterol and WBC count were selected. The risk score was 0.0488xage (years)-0.5810xtotal cholesterol (mmol/l, coded to 4.3 if >4.3)-0.3596xWBC count (10(9) counts/l, 5.8 if >5.8)+0.6390xcurrent smoking status (1 if yes). The 5-year probability of cancer was 1-0.9590(EXP(0.9382x(RISK SCORE+1.5903))). The predicted cancer probability was not significantly different from the observed cancer probability during the 5-year follow-up. The adjusted area under receiver operating characteristic curve was 0.712. In conclusion, BMI, lipids and WBC count have predicting values for cancer.


Assuntos
Colesterol/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Contagem de Leucócitos , Neoplasias/epidemiologia , Idoso , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/metabolismo , Dinâmica não Linear , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fumar/epidemiologia
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