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OBJECTIVE: The outcomes of sepsis and septic shock patients are heterogonous, with avariable response despite standardized care. The aim of this study was toexplore the racial differences in septic shock outcomes, and theirassociation with genetic polymorphisms and cytokine levels in an Asianpopulation. MATERIALS AND METHODS: This was an observational cohort study with Intensive Care units of a 500bedded tertiary care hospital in Singapore. 198 patients (73 Chinese, 73Malay and 52 Indian and others) admitted to the Khoo Teck Puat HospitalIntensive Care Unit between August 2016 and June 2017, with a diagnosis ofsevere sepsis (according to) were enrolled. Plasma interlukin-6 (IL-6),interlukin-10 (IL-10) and tumour necrosis factor-a (TNFa) were measuredusing a highly sensitive quantitative sandwich enzyme-linked immunosorbentassay (ELISA) (BioVendor, Modrice, Czech Republic). The gene panel studiedincluded 16 genes. RESULTS: The rs7038903 common variant in SVEP1 gene showed significant associationwith sepsis severity independent of other variants in ordinal logistic andlinear regression model (p = 0.001 and p = 0.002 respectively). Moreover, the association between rs7038903 and increased hazard for death remained significant after further adjusting for cytokines level. Interestingly, significant differences were seen in plasma IL6 inindividuals with or without rs7038903 C allele (28pg/ml (IQR 12-86) vs90pg/ml (IQR 49-155); P=0.022) in patients with severe sepsis in the Malayethnic group. CONCLUSION: Our study shows a promising polymorphism in SVEP1 gene (rs7038903) which isassociated with sepsis shock and 28 days mortality, independent of age, gender, and method of diagnosis and SOFA score. Collectively, while our findings so far have shown the additional value or measuring cytokines andgenetic markers in sepsis outcomes in the local population, further largescare studies are needed in a heterogeneous septic population with arigorous analysis to know the significance of our findings. HOW TO CITE THIS ARTICLE: Siddiqui S, Gurung RL et al. Genetic Polymorphisms and Cytokine Profile of Different Ethnicities in Septic Shock Patients, and their Association with Mortality. Indian J Crit Care Med 2019;29(3):135-138.
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In normal human somatic cells, telomere dysfunction causes cellular senescence, a stable proliferative arrest with tumour suppressing properties. Whether telomere dysfunction-induced senescence (TDIS) suppresses cancer growth in humans, however, is unknown. Here, we demonstrate that multiple and distinct human cancer precursor lesions, but not corresponding malignant cancers, are comprised of cells that display hallmarks of TDIS. Furthermore, we demonstrate that oncogenic signalling, frequently associated with initiating cancer growth in humans, dramatically affected telomere structure and function by causing telomeric replication stress, rapid and stochastic telomere attrition, and consequently telomere dysfunction in cells that lack hTERT activity. DNA replication stress induced by drugs also resulted in telomere dysfunction and cellular senescence in normal human cells, demonstrating that telomeric repeats indeed are hypersensitive to DNA replication stress. Our data reveal that TDIS, accelerated by oncogene-induced DNA replication stress, is a biological response of cells in human cancer precursor lesions and provide strong evidence that TDIS is a critical tumour suppressing mechanism in humans.
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Senescência Celular/fisiologia , Oncogenes/fisiologia , Telômero/fisiologia , Linhagem Celular , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/genética , Replicação do DNA/fisiologia , Humanos , Oncogenes/efeitos dos fármacos , Oncogenes/genética , Inibidores da Síntese de Proteínas/farmacologia , Puromicina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Telômero/efeitos dos fármacos , Telômero/genéticaRESUMO
BACKGROUND: Patients suffering from brain tumours such as glioblastoma and medulloblastoma have poor prognosis with a median survival of less than a year. Identifying alternative molecular targets would enable us to develop different therapeutic strategies for better management of these tumours. METHODS: Glioblastoma (MO59K and KNS60) and medulloblastoma cells (ONS76) were used in this study. Telomerase inhibitory effects of MST-312, a chemically modified-derivative of epigallocatechin gallate, in the cells were assessed using telomere repeat amplification protocol. Gene expression analysis following MST-312 treatment was done by microarray. Telomere length was measured by telomere restriction fragments analysis. Effects of MST-312 on DNA integrity were evaluated by single cell gel electrophoresis, immunofluorescence assay and cytogenetic analysis. Phosphorylation status of DNA-PKcs was measured with immunoblotting and effects on cell proliferation were monitored with cell titre glow and trypan blue exclusion following dual inhibition. RESULTS: MST-312 showed strong binding affinity to DNA and displayed reversible telomerase inhibitory effects in brain tumour cells. In addition to the disruption of telomere length maintenance, MST-312 treatment decreased brain tumour cell viability, induced cell cycle arrest and double strand breaks (DSBs). DNA-PKcs activation was observed in telomerase-inhibited cells presumably as a response to DNA damage. Impaired DNA-PKcs in MO59J cells or in MO59K cells treated with DNA-PKcs inhibitor, NU7026, caused a delay in the repair of DSBs. In contrast, MST-312 did not induce DSBs in telomerase negative osteosarcoma cells (U2OS). Combined inhibition of DNA-PKcs and telomerase resulted in an increase in telomere signal-free chromosomal ends in brain tumour cells as well. Interestingly, continual exposure of brain tumour cells to telomerase inhibitor led to population of cells, which displayed resistance to telomerase inhibition-mediated cell arrest. DNA-PKcs ablation in these cells, however, confers higher cell sensitivity to telomerase inhibition, inducing cell death. CONCLUSIONS: Efficient telomerase inhibition was achieved with acute exposure to MST-312 and this resulted in subtle but significant increase in DSBs. Activation of DNA-PKcs might indicate the requirement of NHEJ pathway in the repair telomerase inhibitor induced DNA damage. Therefore, our results suggest a potential strategy in combating brain tumour cells with dual inhibition of telomerase and NHEJ pathway.
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Neoplasias Encefálicas/enzimologia , Proteína Quinase Ativada por DNA/metabolismo , Telomerase/metabolismo , Benzamidas/farmacologia , Neoplasias Encefálicas/genética , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telomerase/antagonistas & inibidores , Telômero/metabolismo , Encurtamento do Telômero/efeitos dos fármacosRESUMO
AIM: Among multi-ethnic Asians, type 2 diabetes (T2D) clustered in three subtypes; mild obesity-related diabetes (MOD), mild age-related diabetes with insulin insufficiency (MARD-II) and severe insulin-resistant diabetes with relative insulin insufficiency (SIRD-RII) had differential cardio-renal complication risk. We assessed the proteomic profiles to identify subtype specific biomarkers and its association with diabetes complications. METHODS: 1448 plasma proteins at baseline were measured and compared across the T2D subtypes. Multivariable cox regression was used to assess associations between significant proteomics features and cardio-renal complications. RESULTS: Among 645 T2D participants (SIRD-RII [19%], MOD [45%], MARD-II [36%]), 295 proteins expression differed significantly across the groups. These proteins were enriched in cell adhesion, neurogenesis and inflammatory response processes. In SIRD-RII group, ADH4, ACY1, THOP1, IGFBP2, NEFL, ENTPD2, CALB1, HAO1, CTSV, ITGAV, SCLY, EDA2R, ERBB2 proteins significantly associated with progressive CKD and LILRA5 protein with incident heart failure (HF). In MOD group, TAFA5, RSPO3, EDA2R proteins significantly associated with incident HF. In MARD-II group, FABP4 protein significantly associated with progressive CKD and PTPRN2 protein with major adverse cardiovascular events. Genetically determined NEFL and CALB1 were associated with kidney function decline. CONCLUSIONS: Each T2D subtype has unique proteomics signature and association with clinical outcomes and underlying mechanisms.
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Povo Asiático , Diabetes Mellitus Tipo 2 , Proteômica , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/etiologiaRESUMO
CONTEXT: Patients with younger onset of type 2 diabetes (YT2D) have increased risk for kidney failure compared to those with late onset. However, the mechanism of diabetic kidney disease (DKD) progression in this high-risk group is poorly understood. OBJECTIVES: To identify novel biomarkers and potential causal proteins associated with DKD progression in patients with YT2D. DESIGN AND PARTICIPANTS: Among YT2D (T2D onset age ≤ 40 years), 144 DKD progressors (cases) were matched for T2D onset age, sex, and ethnicity with 292 non-progressors (controls) and divided into discovery and validation sets. DKD progression was defined as decline of estimated glomerular filtration rate (eGFR) of 3ml/min/1.73m2 or greater or 40% decline in eGFR from baseline. 1472 plasma proteins were measured through a multiplex immunoassay that uses a proximity extension assay technology. Multivariable logistic regression was used to identify proteins associated with DKD progression. Mendelian randomization (MR) was used to evaluate causal relationship between plasma proteins and DKD progression. RESULTS: 42 plasma proteins were associated with DKD progression, independent of traditional cardio-renal risk factors, baseline eGFR and urine albumin-to-creatinine ratio (uACR). The proteins identified were related to inflammatory and remodelling biological processes. Our findings suggested angiogenin as one of the top signals (odds ratio =5.29, 95% CI 2.39-11.73, P = 4.03 × 10-5). Furthermore, genetically determined plasma angiogenin level was associated with increased odds of DKD progression. CONCLUSION: Large-scale proteomic analysis identified novel proteomic biomarkers for DKD progression in YT2D. Genetic evidence suggest a causal role of plasma angiogenin in DKD progression.
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AIMS: We aim to determine the association of seven major candidate protein biomarkers and diabetic kidney disease (DKD) progression among Asians with young-onset type 2 diabetes mellitus (T2DM). METHODS: 824 T2DM patients (onset ≤ 40 years old) were classified as DKD progressors based on yearly estimated glomerular filtration rate (eGFR) decline of >3 ml/min/1.73 m2 or >40 % from baseline. Plasma leucine-rich α-2-glycoprotein 1 (pLRG1), tumor necrosis factor-receptor 1 (pTNF-R1), pigment epithelium-derived factor (pPEDF), urinary α-1-microglobulin (uA1M), kidney injury molecular 1 (uKIM-1), haptoglobin (uHP) and uromodulin (uUMOD) were measured using enzyme-linked immunoassays. RESULTS: Over 5.7 years of follow-up, 25.2 % of patients were DKD progressors. Elevated levels of pLRG1, pTNF-R1, pPEDF, uA1M, uKIM-1 and uHP were associated with DKD progression. The association between pTNF-R1 levels and DKD progression persisted after adjusting for clinical covariates (OR 1.84, 95 %CI 1.44-2.34, p < 0.001). The effects of pTNF-R1 were partially mediated through hyperglycemia (8 %) and albuminuria (10 %). Inclusion of pTNF-R1 in a clinical variable-based model improved the area under the receiver operating characteristics curve for predicting DKD progression by 0.02, from 0.72 (95 %CI 0.68-0.76) to 0.74 (95 %CI 0.70-0.78), p = 0.099. CONCLUSIONS: Among seven major candidate proteins, pTNF-R1, partially mediated through hyperglycemia and albuminuria, robustly predicted DKD progression among Asians with young-onset T2DM.
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CONTEXT: Observational studies have shown that elevated uric acid (UA) is associated with chronic kidney disease (CKD). However, whether the relationship is causal remains unclear. OBJECTIVE: To determine the association of plasma UA and incident CKD and the causal relationship between plasma UA and rapid decline in kidney function (RDKF) in patients with type 2 diabetes (T2D). METHODS: Multivariable Cox regression was conducted to evaluate the hazard ratio (HR) between plasma UA and incident CKD among 1300 normoalbuminuric patients in 2 T2D study cohorts (DN, nâ =â 402; SMART2D, n = 898). A weighted genetic risk score (wGRS) was calculated based on 10 single nucleotide polymorphism (SNPs) identified in genome-wide association studies of UA in East Asians. Mendelian randomization (MR) analysis was performed among 1146 Chinese T2D patients without CKD (estimated glomerular filtration rate [eGFR] > 60 mL/min/1.73m2) at baseline (DN, 478; SMART2D, 668). The wGRS and individual SNPs were used as genetic instruments and RDKF was defined as eGFR decline of 5 mL/min/1.73m2/year or greater. RESULTS: During mean follow-up of 5.2 and 5.4 years, 81 (9%) and 46 (11%) participants in SMART2D and DN developed CKD, respectively. A 1-SD increment in plasma UA conferred higher risk of incident CKD (DN, adjusted-HR = 1.40 [95% CI, 1.02-1.91], P = 0.036; SMART2D, adjusted-HR = 1.31 [95% CI, 1.04-1.64], P = 0.018). Higher wGRS was associated with increased odds for RDKF (meta-adjusted odds ratio = 1.12 [95% CI, 1.01-1.24], P = 0.030, Phet = 0.606). CONCLUSION: Elevated plasma UA is an independent risk factor for incident CKD. Furthermore, plasma UA potentially has a causal role in early eGFR loss in T2D patients.
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Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Progressão da Doença , Estudo de Associação Genômica Ampla , Taxa de Filtração Glomerular/genética , Humanos , Rim , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/genética , Fatores de Risco , Ácido ÚricoRESUMO
CONTEXT: Elevated levels of plasma leucine-rich α-2-glycoprotein 1 (LRG1), a component of transforming growth factor beta signaling, are associated with development and progression of chronic kidney disease in patients with type 2 diabetes (T2D). However, whether this relationship is causal is uncertain. OBJECTIVES: To identify genetic variants associated with plasma LRG1 levels and determine whether genetically predicted plasma LRG1 contributes to a rapid decline in kidney function (RDKF) in patients with T2D. DESIGN AND PARTICIPANTS: We performed a genome-wide association study of plasma LRG1 among 3694 T2D individuals [1881 (983 Chinese, 420 Malay, and 478 Indian) discovery from Singapore Study of Macro-angiopathy and Micro-vascular Reactivity in Type 2 Diabetes cohort and 1813 (Chinese) validation from Diabetic Nephropathy cohort]. One- sample Mendelian randomization analysis was performed among 1337 T2D Chinese participants with preserved glomerular filtration function [baseline estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2)]. RDKF was defined as an eGFR decline of 3 mL/min/1.73 m2/year or greater. RESULTS: We identified rs4806985 variant near LRG1 locus robustly associated with plasma LRG1 levels (meta Pâ =â 6.66â ×â 10-16). Among 1337 participants, 344 (26%) developed RDKF, and the rs4806985 variant was associated with higher odds of RDKF (meta odds ratioâ =â 1.23, Pâ =â 0.030 adjusted for age and sex). Mendelian randomization analysis provided evidence for a potential causal effect of plasma LRG1 on kidney function decline in T2D (Pâ <â 0.05). CONCLUSION: We demonstrate that genetically influenced plasma LRG1 increases the risk of RDKF in T2D patients, suggesting plasma LRG1 as a potential treatment target. However, further studies are warranted to elucidate underlying pathways to provide insight into diabetic kidney disease prevention.
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Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/genética , Variação Genética , Glicoproteínas/genética , Rim/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/fisiopatologia , Progressão da Doença , Feminino , Estudo de Associação Genômica Ampla , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Obesity and shorter telomeres increase the risk for diabetes complications and mortality. However, the relationship between obesity and telomere length in diverse Asian populations with type 2 diabetes (T2D) is not well understood. This study examined the association of baseline and changes in obesity indices with telomere length in multiethnic Asian populations with T2D. METHODS: Leukocyte telomere length (LTL) was measured by quantitative polymerase chain reaction in the SMART2D cohort (n = 1431 at baseline, n = 1039 after 3.2 years median follow-up). Associations between obesity indices and LTL were assessed by linear regression. RESULTS: Compared with Chinese, LTL was longer in Malays (P < 0.0001) and similar in Indians. Cross-sectionally, body mass index (BMI)-adjusted (residual) visceral fat area (VFA; ß = -0.004, P = 0.006), and waist-to-hip ratio (ß = -1.95, P = 0.030) were significantly associated with LTL in Chinese but not in Malays and Indians. Changes in BMI (r = -0.080; P = 0.053) and VFA (r = -0.126; P = 0.002) were inversely correlated with changes in LTL only in Chinese. Furthermore, in Chinese, 1-SD incremental changes in BMI (ß = -0.070; P = 0.040) and VFA (ß = -0.088, P = 0.028) were significantly associated with larger telomere attrition, independent of age, sex, diabetes condition, baseline LTL, obesity, and inflammation markers. CONCLUSIONS: Three-year changes in BMI and VFA were associated with telomere dynamics in Chinese but not in Malays and Indians with T2D. Reducing obesity may reduce the risk of diabetes complications associated with shorter LTL in the Chinese population.
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Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Etnicidade/estatística & dados numéricos , Obesidade/complicações , Homeostase do Telômero , Adulto , Idoso , Idoso de 80 Anos ou mais , Ásia/epidemiologia , Índice de Massa Corporal , Estudos Transversais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto JovemRESUMO
Genetic factors underlying leukocyte telomere length (LTL) may provide insights into telomere homeostasis, with direct links to disease susceptibility. Genetic evaluation of 23,096 Singaporean Chinese samples identifies 10 genome-wide loci (P < 5 × 10-8). Several of these contain candidate genes (TINF2, PARP1, TERF1, ATM and POT1) with potential roles in telomere biology and DNA repair mechanisms. Meta-analyses with additional 37,505 European individuals reveals six more genome-wide loci, including associations at MPHOSPH6, NKX2-3 and TYMS. We demonstrate that longer LTL associates with protection against respiratory disease mortality [HR = 0.854(0.804-0.906), P = 1.88 × 10-7] in the Singaporean Chinese samples. We further show that the LTL reducing SNP rs7253490 associates with respiratory infections (P = 7.44 × 10-4) although this effect may not be strongly mediated through LTL. Our data expands on the genetic basis of LTL and may indicate on a potential role of LTL in immune competence.
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Povo Asiático/genética , Reparo do DNA/genética , Leucócitos/metabolismo , Homeostase do Telômero/genética , Telômero/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções Respiratórias/genética , Singapura , População Branca/genética , Adulto JovemRESUMO
INTRODUCTION: Telomere length, a marker for biological aging, is implicated with diabetic kidney disease (DKD); however, the association between telomere length and albuminuria progression among Asian patients with type 2 diabetes (T2D) is not well understood. Here, we aim to study whether leukocyte telomere length (LTL) may independently predict albuminuria progression in patients with T2D with preserved renal filtration function (estimated GFR >60 ml/min per 1.73 m2 and urine albumin-to-creatinine ratio [uACR] <300 mg/g). METHODS: The baseline LTL was measured by real-time polymerase chain reaction in the SMART2D cohort (n = 691) with a median follow-up of 3 years. Albuminuria progression was defined as a change in albuminuria category to a higher category and at least 30% increase in uACR from baseline in 3 years. RESULTS: Progressors (n = 123) had significantly shorter median LTL compared with nonprogressors (n = 568) (0.58 [0.38-0.79] vs. 0.62 [0.45-0.88], P = 0.039). Compared with subjects with longer LTL (fourth quartile), subjects with shorter LTL (first quartile) had 1.93-fold (1.04-3.60, P = 0.038) increased risk for albuminuria progression after adjustment for traditional risk factors. The association of LTL with microalbuminuria to macroalbuminuria progression was stronger than its association with normoalbuminuria to microalbuminuria (odds ratio [OR]: 1.54; 95% confidence interval [CI]: 1.02-2.32; P = 0.042 vs. OR: 1.13; 95% CI: 0.91-1.40; P = 0.263 per 1-SD decrement in natural log-transformed LTL). CONCLUSION: Therefore, our results demonstrated that in patients with T2D with preserved renal filtration function, LTL predicts albuminuria progression beyond traditional risk factors, suggesting LTL may be novel biomarker for DKD progression.
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Urine haptoglobin (uHP) level prospectively predicts diabetic kidney disease (DKD) progression. Here, we aim to identify genetic determinants of uHP level and evaluate association with renal function in East Asians (EA) with type 2 diabetes (T2D). Genome-wide association study (GWAS) among 805 [236 Chinese (discovery) and 569 (57 Malay and 512 Chinese) (validation)] found that rs75444904/kgp16506790 variant was robustly associated with uHP level (MetaP = 1.21 × 10-60). rs75444904 correlates well with plasma HP protein levels and multimerization in EA but was not in perfect LD (r2 = 0.911 in Chinese, r2 = 0.536 in Malay) and is monomorphic in Europeans (1000 G data). Conditional probability analysis indicated weakening of effects but residual significant associations between rs75444904 and uHP when adjusted on HP structural variant (MetaP = 8.22 × 10-7). The rs75444904 variant was associated with DKD progression (OR = 1.77, P = 0.014) independent of traditional risk factors. In an additional validation-cohort of EA (410 end-stage renal disease (ESRD) cases and 1308 controls), rs75444904 was associated with ESRD (OR = 1.22, P = 0.036). Furthermore, increased risk of DKD progression (OR = 2.09, P = 0.007) with elevated uHP level through Mendelian randomisation analysis provide support for potential causal role of uHP in DKD progression in EA. However, further replication of our findings in larger study populations is warranted.
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Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Haptoglobinas , Polimorfismo Genético , Idoso , Povo Asiático , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/urina , Feminino , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Haptoglobinas/genética , Haptoglobinas/urina , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/urina , Masculino , Pessoa de Meia-IdadeRESUMO
Silver nanoparticles (Ag-np) were reported to be toxic to eukaryotic cells. These potentially detrimental effects of Ag-np can be advantageous in experimental therapeutics. They are currently being employed to enhance the therapeutic efficacy of cancer drugs. In this study, we demonstrate that Ag-np treatment trigger the activation of DNA-PKcs and JNK pathway at selected doses, presumably as a physiologic response to DNA damage and repair in normal and malignant cells. Ag-np altered the telomere dynamics by disrupting the shelterin complex located at the telomeres and telomere lengths. The genotoxic effect of Ag-np was not restricted to telomeres but the entire genome as Ag-np induced γ-H2AX foci formation, an indicator of global DNA damage. Inhibition of DNA-PKcs activity sensitised the cancer cells towards the cytotoxicity of Ag-np and substantiated the damaging effect of Ag-np at telomeres in human cancer cells. Abrogation of JNK mediated DNA repair and extensive damage of telomeres led to greater cell death following Ag-np treatment in DNA-PKcs inhibited cancer cells. Collectively, this study suggests that improved anti-proliferative and cytotoxic effects of Ag-np treatment in cancer cells can be achieved by the inhibition of DNA-PKcs.
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Antineoplásicos/farmacologia , Proteína Quinase Ativada por DNA/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Proteínas Nucleares/metabolismo , Prata/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Proteína Quinase Ativada por DNA/genética , Feminino , Humanos , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Células MCF-7 , Nanopartículas Metálicas/química , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Nucleares/genética , Prata/química , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero/efeitos dos fármacos , Homeostase do Telômero/genéticaRESUMO
CONTEXT: A recent study suggested that urinary haptoglobin may be a novel biomarker to improve predictive performance of albuminuria in type 2 diabetes mellitus (T2DM). However, the finding has not been externally validated. OBJECTIVE: The objective of the study was to evaluate whether urinary haptoglobin improves predictive performance of albuminuria in Asian T2DM with an estimated glomerular filtration rate (eGFR) of 30 mL/min per 1.73 m2 or greater. DESIGN AND PARTICIPANTS: This was a prospective study with 269 T2DM nonprogressors (eGFR changes 0.2 [-0.7 to 1.0] mL/min per 1.73 m2 per y) and 153 T2DM progressors (eGFR decline -7.1 [-10.6 to -5.1] mL/min per 1.73 m2 per y) included. MAIN OUTCOME: The main outcome was an eGFR decline of 3 mL/min per 1.73 m2 or greater per year by trajectory slope. RESULTS: Urinary haptoglobin level increased 11-fold in progressors as compared with nonprogressors at baseline. In comparison with subjects in the lowest quartile, those with haptoglobin in the third and fourth quartiles had 2.25- (1.11-4.59) and 5.41 (2.63-11.1)-fold increased odds for renal progression, whereas those with an albuminuria level in the third and fourth quartiles had 2.53- (1.17-5.51) and 9.01 (4.00-20.5)-fold increased odds. Notably, urinary haptoglobin predicted renal progression independent of albuminuria. Addition of haptoglobin significantly improved the predictive performance of albuminuria beyond traditional risk factors as reflected by a significant increase in the net reclassification index and integrated discrimination index. In the chronic kidney disease stage 3 subpopulation, urinary haptoglobin outperformed albuminuria for the prediction of rapid renal function decline. CONCLUSIONS: Our data confirmed that urinary haptoglobin may improve the predictive performance of albuminuria for renal progression in Asians with T2DM. Moreover, it may potentially outperform albuminuria for the prediction of rapid renal function decline in the T2DM chronic kidney disease stage 3 subpopulation.
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Albuminúria/urina , Povo Asiático/etnologia , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/urina , Taxa de Filtração Glomerular , Haptoglobinas/urina , Adulto , Idoso , Biomarcadores/urina , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/etnologia , Nefropatias Diabéticas/etnologia , Nefropatias Diabéticas/etiologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Singapura/etnologiaRESUMO
BACKGROUND: Targeting telomerase is a potential cancer management strategy given that it allows unlimited cellular replication in the majority of cancers. Dysfunctional telomeres are recognized as double-strand breaks. However, the status of DNA repair response pathways following telomerase inhibition is not well understood in human breast cancer cells. Here, we evaluated the effects of MST-312, a chemically modified derivative from tea catechin, epigallocatechin gallate, on telomere dynamics and DNA damage gene expression in breast cancer cells. METHODOLOGY: Breast cancer cells MCF-7 and MDA-MB-231 were treated with MST-312, and telomere-telomerase homeostasis, induced DNA damage and gene expression profiling were analyzed. RESULTS: MST-312 decreased telomerase activity and induced telomere dysfunction and growth arrest in breast cancer cells with more profound effects in MDA-MB-231 than in MCF-7 cells. Consistent with these data, the telomere-protective protein TRF2 was downregulated in MDA-MB-231 cells. MST-312 induced DNA damage at telomeres accompanied by reduced expression of DNA damage-related genes ATM and RAD50. Co-treatment with MST-312 and the poly(ADP-ribose) polymerase 1 (PARP-1) inhibitor PJ-34 further enhanced growth reduction as compared to single treatment with MST-312 or PJ-34. CONCLUSIONS: Our work demonstrates potential importance for the establishment of antitelomerase cancer therapy using MST-312 along with PARP-1 inhibition in breast cancer therapy.
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Benzamidas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Telômero/efeitos dos fármacos , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Benzamidas/administração & dosagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Células MCF-7 , Nutrigenômica , Fenantrenos/administração & dosagem , Fenantrenos/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Reparo de DNA por Recombinação/efeitos dos fármacos , Reparo de DNA por Recombinação/genética , Telomerase/antagonistas & inibidores , Telômero/genética , Encurtamento do Telômero/efeitos dos fármacos , Transcriptoma/efeitos dos fármacosRESUMO
Gold nanoparticles (AuNPs) have diverse applications in the biomedical industry such as in diagnosis, labeling, delivering and sensing. Despite their prevalent medical use, nanotoxicity induced by AuNPs is still largely unknown. We have previously shown that AuNPs could exert cytotoxic effects on lung fibroblasts. In this study, we investigated the in vitro toxicological effects of AuNPs in small airway epithelial cells (SAECs) which are the first cells of contact for inhaled NPs and compared expression of metallothionein (MT), a reactive oxygen species scavenger, in SAECs and lung fibroblasts in vitro. Transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) spectroscopy study revealed cellular uptake of aggregates of AuNPs into the cytoplasm at the ultrastructural level. A significant increase in lipid peroxide as well as substantial DNA damage and cytotoxicity was observed in AuNP-treated cells. For MT expression, AuNPs induced down-regulation of the MT-1X isoform in SAECs, but up-regulation of the MT-1X and MT-2 A isoforms in MRC5 lung fibroblasts. The present study suggests that AuNPs could induce oxidative stress-related cytotoxicity and genotoxicity in SAECs.
Assuntos
Células Epiteliais/efeitos dos fármacos , Ouro/toxicidade , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Fibroblastos/efeitos dos fármacos , Humanos , Pulmão/citologia , Metalotioneína/metabolismo , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Gold nanoparticles (AuNPs) are one of the most versatile and widely researched materials for novel biomedical applications. However, the current knowledge in their toxicological profile is still incomplete and many on-going investigations aim to understand the potential adverse effects in human body. Here, we employed two dimensional gel electrophoresis to perform a comparative proteomic analysis of AuNP treated MRC-5 lung fibroblast cells. In our findings, we identified 16 proteins that were differentially expressed in MRC-5 lung fibroblasts following exposure to AuNPs. Their expression levels were also verified by western blotting and real time RT-PCR analysis. Of interest was the difference in the oxidative stress related proteins (NADH ubiquinone oxidoreductase (NDUFS1), protein disulfide isomerase associate 3 (PDIA3), heterogeneous nuclear ribonucleus protein C1/C2 (hnRNP C1/C2) and thioredoxin-like protein 1 (TXNL1)) as well as proteins associated with cell cycle regulation, cytoskeleton and DNA repair (heterogeneous nuclear ribonucleus protein C1/C2 (hnRNP C1/C2) and Secernin-1 (SCN1)). This finding is consistent with the genotoxicity observed in the AuNP treated lung fibroblasts. These results suggest that AuNP treatment can induce oxidative stress-mediated genomic instability.
Assuntos
Fibroblastos/efeitos dos fármacos , Instabilidade Genômica/efeitos dos fármacos , Ouro/farmacologia , Pulmão/citologia , Nanopartículas Metálicas/efeitos adversos , Linhagem Celular , Quebra Cromossômica/efeitos dos fármacos , Ensaio Cometa , Regulação para Baixo/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Fibroblastos/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Hibridização in Situ Fluorescente , Proteínas/genética , Proteínas/metabolismo , Proteômica/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Regulação para Cima/efeitos dos fármacosRESUMO
BACKGROUND: A major concern of cancer chemotherapy is the side effects caused by the non-specific targeting of both normal and cancerous cells by therapeutic drugs. Much emphasis has been placed on discovering new compounds that target tumour cells more efficiently and selectively with minimal toxic effects on normal cells. METHODOLOGY/PRINCIPAL FINDINGS: The cytotoxic effect of thymoquinone, a component derived from the plant Nigella sativa, was tested on human glioblastoma and normal cells. Our findings demonstrated that glioblastoma cells were more sensitive to thymoquinone-induced antiproliferative effects. Thymoquinone induced DNA damage, cell cycle arrest and apoptosis in the glioblastoma cells. It was also observed that thymoquinone facilitated telomere attrition by inhibiting the activity of telomerase. In addition to these, we investigated the role of DNA-PKcs on thymoquinone mediated changes in telomere length. Telomeres in glioblastoma cells with DNA-PKcs were more sensitive to thymoquinone mediated effects as compared to those cells deficient in DNA-PKcs. CONCLUSIONS/SIGNIFICANCE: Our results indicate that thymoquinone induces DNA damage, telomere attrition by inhibiting telomerase and cell death in glioblastoma cells. Telomere shortening was found to be dependent on the status of DNA-PKcs. Collectively, these data suggest that thymoquinone could be useful as a potential chemotherapeutic agent in the management for brain tumours.