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1.
Biol Psychiatry ; 95(5): 426-433, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355004

RESUMO

BACKGROUND: Clinical trials suggest that long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) (fish oil) may reduce depressive symptoms in adults with major depressive disorder. Therefore, n-3 PUFAs may be a potential treatment for depression in youth. METHODS: Participants were 15- to-25 year-old individuals with major depressive disorder who sought care in one of three government-funded mental health services for young people in metropolitan Melbourne, Perth, or Sydney, Australia. Participants were randomly assigned in a double-blind, parallel-arm design to receive either fish oil (840 mg of eicosapentaenoic acid and 560 mg of docosahexaenoic acid) or placebo capsules as adjunct to cognitive behavioral case management. All participants were offered 50-minute cognitive behavioral case management sessions every 2 weeks delivered by qualified therapists (treatment as usual) at the study sites during the intervention period. The primary outcome was change in the interviewer-rated Quick Inventory of Depressive Symptomatology, Adolescent Version, score at 12 weeks. Erythrocyte n-3 PUFA levels were assessed pre-post intervention. RESULTS: A total of 233 young people were randomized to the treatment arms: 115 participants to the n-3 PUFA group and 118 to the placebo group. Mean change from baseline in the Quick Inventory of Depressive Symptomatology score was -5.8 in the n-3 PUFA group and -5.6 in the placebo group (mean difference, 0.2; 95% CI, -1.1 to 1.5; p = .75). Erythrocyte PUFA levels were not associated with depression severity at any time point. The incidence and severity of adverse events were similar in the two groups. CONCLUSIONS: This placebo-controlled trial and biomarker analysis found no evidence to support the use of fish oil for treatment in young people with major depressive disorder.


Assuntos
Transtorno Depressivo Maior , Ácidos Graxos Ômega-3 , Humanos , Adolescente , Adulto , Adulto Jovem , Óleos de Peixe/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Depressão , Administração de Caso , Ácidos Graxos Ômega-3/uso terapêutico , Método Duplo-Cego , Cognição
2.
Psychol Sport Exerc ; 64: 102325, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37665810

RESUMO

BACKGROUND: Women with polycystic ovary syndrome (PCOS) experience general and PCOS-specific barriers that limit their engagement with exercise and contribute to high attrition from exercise programs, hindering the potential benefits of exercise to address their increased cardio-metabolic risk. A positive remembered affective response can predict future intentions and adherence to exercise prescription. OBJECTIVES: To compare the longitudinal changes in remembered affect to high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in women with PCOS and to determine whether longitudinal changes in remembered affect are correlated with changes in fitness, body mass index, adherence and exercise enjoyment. METHODS: Physically inactive, overweight women with PCOS were randomly assigned to 12 weeks of either HIIT (n = 15) or MICT (n = 14) (3 sessions per week). Remembered affective valence (Feeling Scale) was collected after each exercise session. Cardiorespiratory fitness (VO2peak) was assessed at baseline and post-intervention. Exercise enjoyment was assessed post-intervention. RESULTS: The longitudinal changes in the remembered affect were more positive in the HIIT group compared to MICT (ß = 0.017, p = 0.047). HIIT was also considered more enjoyable than MICT (p = 0.002). Adherence was high in both groups (>90%). We found a moderate correlation with longitudinal changes between the remembered affect and change in fitness (rs = 0.398) and exercise enjoyment (rs = 0.376) using the combined group, however, these were not statistically significant (p = 0.054 and p = 0.064, respectively). CONCLUSIONS: HIIT demonstrated a more positive longitudinal remembered affective response and greater exercise enjoyment compared to MICT in overweight women with PCOS.


Assuntos
Treinamento Intervalado de Alta Intensidade , Síndrome do Ovário Policístico , Humanos , Feminino , Sobrepeso/complicações , Síndrome do Ovário Policístico/complicações , Prazer , Felicidade
3.
Sci Rep ; 13(1): 3025, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810865

RESUMO

Women with PCOS have substantially greater symptoms of depression and anxiety, and a lower health-related quality of life (HRQoL) compared to women without PCOS. The aim of this study was to determine if high-intensity interval training (HIIT) could provide greater improvements in mental health outcomes than standard moderate-intensity continuous training (MICT). Twenty-nine overweight women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% HRpeak, N = 15) or HIIT (> 90% HRpeak, N = 14). Outcome measures included symptoms of depression, anxiety and stress (DASS-21), general HRQoL (SF-36) and PCOS specific HRQoL (PCOSQ) collected at baseline and post-intervention. Reductions in depression (Δ - 1.7, P = 0.005), anxiety (Δ - 3.4, P < 0.001) and stress (Δ - 2.4, P = 0.003) scores were observed in the HIIT group, while MICT only resulted in a reduction in stress scores (Δ - 2.9, P = 0.001). Reductions in anxiety scores were significantly higher in the HIIT group compared to the MICT group (ß = - 2.24, P = 0.020). Both HIIT and MICT significantly improved multiple domain scores from the SF-36 and PCOSQ. This study highlights the potential of HIIT for improving mental health and HRQoL in overweight women with PCOS. HIIT may be a viable strategy to reduce symptoms of depression and anxiety in women with PCOS, however, large-scale studies are required to confirm these findings.Trial registration number: ACTRN12615000242527.


Assuntos
Treinamento Intervalado de Alta Intensidade , Síndrome do Ovário Policístico , Humanos , Feminino , Qualidade de Vida , Sobrepeso , Saúde Mental , Treinamento Intervalado de Alta Intensidade/métodos
4.
Nicotine Tob Res ; 25(4): 682-691, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35665823

RESUMO

INTRODUCTION: In Australian youth primary mental health settings it is unclear as to the rates and correlates of tobacco use at service entry. AIMS AND METHODS: We aimed to delineate the prevalence and correlates of recent tobacco use (eg, cigarettes, chewing tobacco, cigars, etc) in the past 3 months in young people at their first presentation to primary mental health services as a function of age. Cross-sectional self-report measures were collected using a tablet device from young people presenting to one of five Australian primary mental health (headspace) services. Logistic regression assessed correlates of past 3-month tobacco use in adolescents (12-17 years) and young adults (18-25 years). RESULTS: Regular (at least monthly) tobacco use in the past 3 months was found in 23.4% (n = 247, N = 1055) of the sample. Increasing age (odds ratio [OR] =1.47 per year; 95% confidence interval [CI]: 1.15 to 1.89), male sex (OR = 1.98; 95% CI: 1.02 to 3.83), being in a relationship (OR = 1.96; 95% CI: 1.01 to 3.82), and poorer functioning (OR = 0.95 per unit Social and Occupational Functioning Assessment Scale increase; 95% CI: 0.91 to 0.99) predicted regular tobacco use in adolescents, but not in young adults. Living in a regional location (OR = 2.10; 95% CI: 1.40 to 3.13) and not studying (OR = 0.47; 95% CI: 0.31 to 0.73) predicted tobacco use in young adults. Having a diagnosed mental illness other than depression and/or anxiety predicted tobacco use in both groups (adolescents OR = 2.49; 95% CI: 1.26 to 4.94; young adults OR = 1.80; 95% CI: 1.13 to 2.89). CONCLUSIONS: Nearly a quarter of young people with mental illness are using tobacco, supporting the need for early intervention approaches. Adapting treatment targets by age could improve the impact of interventions in adolescents versus young adults. Poor functioning and lack of engagement in education were associated with tobacco use in both age groups, respectively; however, more research is needed to determine the direction of these relationships. IMPLICATIONS: Young people with mental illness have a high prevalence of recent tobacco use and this is evident when they first present to youth primary mental health services. Youth-oriented mental health settings may provide a unique window for tobacco use prevention and early intervention to reduce smoking in people with mental illness, a priority population. Age-specific targeted approaches might be needed in adolescents and young adults.


Assuntos
Serviços de Saúde Mental , Uso de Tabaco , Adulto Jovem , Adolescente , Humanos , Masculino , Prevalência , Estudos Transversais , Austrália/epidemiologia , Uso de Tabaco/epidemiologia
5.
Hum Reprod ; 37(5): 1018-1029, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35325125

RESUMO

STUDY QUESTION: Does 12 weeks of high-intensity interval training (HIIT) result in greater improvements in cardio-metabolic and reproductive outcomes compared to standard moderate-intensity continuous training (MICT) in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: HIIT offers greater improvements in aerobic capacity, insulin sensitivity and menstrual cyclicity, and larger reductions in hyperandrogenism compared to MICT. WHAT IS KNOWN ALREADY: Exercise training is recognized to improve clinical outcomes in women with PCOS, but little is known about whether HIIT results in greater health outcomes compared to standard MICT. STUDY DESIGN, SIZE, DURATION: This was a two-armed randomized clinical trial enrolling a total of 29 overweight women with PCOS between May 2016 and November 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% peak heart rate, N = 14) or HIIT (>90% peak heart rate, N = 15), each completed three times per week. The primary clinical outcomes were aerobic capacity (VO2peak) and insulin sensitivity (euglycaemic-hyperinsulinaemic clamp). Secondary outcomes included hormonal profiles, menstrual cyclicity and body composition. MAIN RESULTS AND THE ROLE OF CHANCE: Both HIIT and MICT improved VO2peak (HIIT; Δ 5.8 ± 2.6 ml/kg/min, P < 0.001 and MICT; Δ 3.2 ± 2 ml/kg/min, P < 0.001), however, the HIIT group had a greater improvement in aerobic capacity compared to MICT (ß = 2.73 ml/kg/min, P = 0.015). HIIT increased the insulin sensitivity index compared to baseline (Δ 2.3 ± 4.4 AU, P = 0.007) and MICT (ß = 0.36 AU, P = 0.030), and caused higher increases in sex hormone-binding globulin compared to MICT (ß = 0.25 nmol/l, P = 0.002). HIIT participants were 7.8 times more likely to report improved menstrual cyclicity than those in the MICT group (odds ratio 7.8, P = 0.04). LIMITATIONS, REASONS FOR CAUTION: This study has a small sample size and the findings of the effect of the exercise interventions are limited to overweight reproductive-aged women, who do not have any co-existing co-morbidities that require medication. WIDER IMPLICATIONS OF THE FINDINGS: Exercise, regardless of intensity, has clear health benefits for women with PCOS. HIIT appears to be a more beneficial strategy and should be considered for promoting health and reducing cardio-metabolic risk in overweight women with PCOS. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a Project Support Grant from the Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence in PCOS. The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: ACTRN12615000242527. TRIAL REGISTRATION DATE: 19 February 2015. DATE OF FIRST PATIENT'S ENROLMENT: 27 May 2016.


Assuntos
Treinamento Intervalado de Alta Intensidade , Resistência à Insulina , Síndrome do Ovário Policístico , Adulto , Austrália , Feminino , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Sobrepeso/complicações , Sobrepeso/terapia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia
6.
BMC Public Health ; 21(1): 2310, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930180

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex condition, impacting cardio-metabolic and reproductive health, mental health and health-related quality of life. The physical health benefits of exercise for women with PCOS are well-established and exercise is increasingly being recognised as efficacious for improving psychological wellbeing. The aim of this review was to summarise the evidence regarding the effectiveness of exercise interventions on mental health outcomes in women with PCOS. METHODS: A systematic search of electronic databases was conducted in March of 2020. Trials that evaluated the effect of an exercise intervention on mental health or health-related quality of life outcomes in reproductive aged women with diagnosed PCOS were included. Methodological quality was assessed using the modified Downs and Black checklist. Primary outcomes included symptoms of depression and anxiety, and health-related quality of life. RESULTS: Fifteen articles from 11 trials were identified and deemed eligible for inclusion. Exercise demonstrated positive improvements in health-related quality of life in all of the included studies. Half of included studies also reported significant improvements in depression and anxiety symptoms. There was large variation in methodological quality of included studies and in the interventions utilised. CONCLUSIONS: The available evidence indicates that exercise is effective for improving health-related quality of life and PCOS symptom distress. Exercise also shows some efficacy for improving symptoms and/or prevalence of depression and anxiety in women with PCOS. However, due to large heterogeneity of included studies, conclusions could not be made regarding the impact of exercise intervention characteristics. High-quality trials with well reported exercise intervention characteristics and outcomes are required in order to determine effective exercise protocols for women with PCOS and facilitate translation into practice.


Assuntos
Síndrome do Ovário Policístico , Adulto , Ansiedade/epidemiologia , Ansiedade/terapia , Depressão/epidemiologia , Depressão/terapia , Terapia por Exercício , Feminino , Humanos , Saúde Mental , Síndrome do Ovário Policístico/epidemiologia , Síndrome do Ovário Policístico/psicologia , Síndrome do Ovário Policístico/terapia , Qualidade de Vida
7.
J Affect Disord ; 295: 235-242, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481152

RESUMO

BACKGROUND: . Suicidal ideation is common in young people. Assessment and monitoring can help to understand its dynamic nature and inform treatment planning. AIMS: . The aims were to evaluate psychometric properties of a brief screening tool - the Youth Suicide Ideation Screen-3 item (YSIS-3) and determine its correlation with the Suicidal Ideation Question-Junior (SIQ-JR) and measures of depressive and anxiety symptoms a. METHOD: . Cronbach's alpha (α) was used to evaluate internal consistency of the YSIS-3 in 1107 young people. Convergent validity was evaluated using network analysis based on individual item polychoric correlations. Structural equation modelling was used to understand latent constructs; pearson product moment correlations to validate the integrity of the underlying construct. and two-way mixed Intraclass Correlation Coefficient to examine longitudinal stability and Cohen's d to assess sensitivity to change. RESULTS: . The YSIS-3 was found to have internal consistency, convergent validity and criteria validity almost identical to the 15-item SIQ-JR. There was a high correlation (0.91) between the latent factor underpinning YSIS-3 and SIQ-JR. The YSIS-3 was more sensitive to change among those presenting with suicidal ideation at baseline. CONCLUSIONS: . The YSIS-3 is a valid measure for the assessment and monitoring of suicidal ideation, and is sensitive to change. This brief measure can contribute to regular monitoring of the presence and nature of suicidal ideation, which when included in comprehensive assessment, will inform the clinical management of those at risk of suicide.


Assuntos
Ansiedade , Ideação Suicida , Adolescente , Humanos , Programas de Rastreamento , Psicometria , Reprodutibilidade dos Testes
8.
Nat Commun ; 12(1): 5166, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34453062

RESUMO

The efficient segregation of replicated genetic material is an essential step for cell division. Bacterial cells use several evolutionarily-distinct genome segregation systems, the most common of which is the type I Par system. It consists of an adapter protein, ParB, that binds to the DNA cargo via interaction with the parS DNA sequence; and an ATPase, ParA, that binds nonspecific DNA and mediates cargo transport. However, the molecular details of how this system functions are not well understood. Here, we report the cryo-EM structure of the Vibrio cholerae ParA2 filament bound to DNA, as well as the crystal structures of this protein in various nucleotide states. These structures show that ParA forms a left-handed filament on DNA, stabilized by nucleotide binding, and that ParA undergoes profound structural rearrangements upon DNA binding and filament assembly. Collectively, our data suggest the structural basis for ParA's cooperative binding to DNA and the formation of high ParA density regions on the nucleoid.


Assuntos
Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , DNA Bacteriano/química , DNA Bacteriano/metabolismo , Vibrio cholerae/metabolismo , Adenosina Trifosfatases/genética , Proteínas de Bactérias/genética , Segregação de Cromossomos , Microscopia Crioeletrônica , Cristalografia por Raios X , DNA Bacteriano/genética , Conformação de Ácido Nucleico , Conformação Proteica , Vibrio cholerae/química , Vibrio cholerae/enzimologia , Vibrio cholerae/genética
9.
Oncotarget ; 8(48): 84258-84275, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-29137421

RESUMO

The estrogen receptor ERß is the predominant ER subtype expressed in normal well-differentiated colonic epithelium. However, ERß expression is lost under the hypoxic microenvironment as colorectal cancer (CRC) malignancy progresses. This raises questions about the role of signalling through other estrogen receptors such as ERα or G-protein coupled estrogen receptor (GPER, GPR30) by the estrogen 17ß-estradiol (E2) under hypoxic conditions after ERß is lost in CRC progression. We tested the hypothesis that E2 or hypoxia can act via GPER to contribute to the altered phenotype of CRC cells. GPER expression was found to be up-regulated by hypoxia and E2 in a panel of CRC cell lines. The E2-modulated gene, Ataxia telangiectasia mutated (ATM), was repressed in hypoxia via GPER signalling. E2 treatment enhanced hypoxia-induced expression of HIF1-α and VEGFA, but repressed HIF1-α and VEGFA expression under normoxic conditions. The expression and repression of VEGFA by E2 were mediated by a GPER-dependent mechanism. E2 treatment potentiated hypoxia-induced CRC cell migration and proliferation, whereas in normoxia, cell migration and proliferation were suppressed by E2 treatment. The effects of E2 on these cellular responses in normoxia and hypoxia were mediated by GPER. In a cohort of 566 CRC patient tumor samples, GPER expression significantly associated with poor survival in CRC Stages 3-4 females but not in the stage-matched male population. Our findings support a potentially pro-tumorigenic role for E2 in ERß-negative CRC under hypoxic conditions transduced via GPER and suggest a novel route of therapeutic intervention through GPER antagonism.

10.
Hum Mol Genet ; 26(8): 1552-1564, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28207045

RESUMO

Solid tumours have oxygen gradients and areas of near and almost total anoxia. Hypoxia reduces sensitivity to 5-fluorouracil (5-FU)-chemotherapy for colorectal cancer (CRC). MicroRNAs (miRNAs) are hypoxia sensors and were altered consistently in six CRC cell lines (colon cancer: DLD-1, HCT116 and HT29; rectal cancer: HT55, SW837 and VACO4S) maintained in hypoxia (1 and 0.2% oxygen) compared with normoxia (20.9%). CRC cell lines also showed altered amino acid metabolism in hypoxia and hypoxia-responsive miRNAs were predicted to target genes in four metabolism pathways: beta-alanine; valine, leucine, iso-leucine; aminoacyl-tRNA; and alanine, aspartate, glutamate. MiR-210 was increased in hypoxic areas of CRC tissues and hypoxia-responsive miR-21 and miR-30d, but not miR-210, were significantly increased in 5-FU resistant CRCs. Treatment with miR-21 and miR-30d antagonists sensitized hypoxic CRC cells to 5-FU. Our data highlight the complexity and tumour heterogeneity caused by hypoxia. MiR-210 as a hypoxic biomarker, and the targeting of miR-21 and miR-30d and/or the amino acid metabolism pathways may offer translational opportunities.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/biossíntese , Aminoácidos/metabolismo , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Heterogeneidade Genética , Células HCT116 , Humanos , MicroRNAs/genética , Oxigênio/metabolismo
11.
Early Interv Psychiatry ; 10(4): 290-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-25130262

RESUMO

AIM: US authorities have recommended 'black-box' warnings for antidepressants because of the increased risk of suicidality for individuals up to age 25. There is thus a clinical and ethical imperative to provide effective treatment for youth depression with an acceptable risk-benefit balance. Long-chain omega-3 polyunsaturated fatty acids (PUFAs) play an important role in a range of physiological processes in living organisms. Supplementation with omega-3 PUFAs has been shown to have a range of beneficial effects on both physical and mental health, and results of previous trials suggest that omega-3 PUFAs may be a safe and effective treatment for depression. However, conclusions from these trials have been limited by their relatively small sample sizes. METHODS: This trial will test the effectiveness of a 12-week parallel group, double-blind, randomized, placebo-controlled trial of 1.4 g day(-1) omega-3 PUFAs in help seeking 15- to 25-year-olds (N = 400) presenting with major depressive disorder. The primary hypothesis is that young people will show greater improvement of depressive symptoms after 12 weeks of treatment with omega-3 PUFAs plus cognitive behavioural case management compared with treatment with placebo plus cognitive behavioural case management. CONCLUSION: Because of using a large sample, results from this study will provide the strongest evidence to date to inform the use of omega-3 PUFAs as first-line therapy in young people presenting with major depressive disorder. The study also heralds an important step towards indicated prevention of persistent depression, which may reduce the burden, stigmatization, disability and economic consequences of this disorder.


Assuntos
Transtorno Depressivo Maior/dietoterapia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/uso terapêutico , Adolescente , Adulto , Antidepressivos/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
13.
Med J Aust ; 200(2): 108-11, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24484115

RESUMO

OBJECTIVES: To provide the first national profile of the characteristics of young people (aged 12-25 years) accessing headspace centre services - the Australian Government's innovation in youth mental health service delivery - and investigate whether headspace is providing early service access for adolescents and young adults with emerging mental health problems. DESIGN AND PARTICIPANTS: Census of all young people accessing a headspace centre across the national network of 55 centres comprising a total of 21 274 headspace clients between 1 January and 30 June 2013. MAIN OUTCOME MEASURES: Reason for presentation, Kessler Psychological Distress Scale, stage of illness, diagnosis, functioning. RESULTS: Young people were most likely to present with mood and anxiety symptoms and disorders, self-reporting their reason for attendance as problems with how they felt. Client demographic characteristics tended to reflect population-level distributions, although clients from regional areas and of Aboriginal and Torres Strait Islander background were particularly well represented, whereas those who were born outside Australia were underrepresented. CONCLUSION: headspace centres are providing a point of service access for young Australians with high levels of psychological distress and need for care in the early stages of the development of mental disorder.


Assuntos
Serviços de Saúde do Adolescente/organização & administração , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Serviços de Saúde Mental/organização & administração , Saúde Mental/estatística & dados numéricos , Programas Nacionais de Saúde/organização & administração , Adolescente , Adulto , Austrália , Criança , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Adulto Jovem
14.
Inflamm Bowel Dis ; 20(3): 514-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24492313

RESUMO

BACKGROUND: NADPH oxidase-derived reactive oxygen species, such as H2O2, are part of the intestinal innate immune system but may drive carcinogenesis through DNA damage. We sought to identify the predominant enzyme system capable of producing H2O2 in active ulcerative colitis and assess whether it is affected by 5-aminosalicylic acid (5-ASA). METHODS: We studied human mucosal biopsies by expression arrays, quantitative real-time polymerase chain reaction for NADPH oxidase family members, in situ hybridization (DUOX2 and DUOXA2) and immunofluorescence for DUOX, 8-OHdG (DNA damage), and γH2AX (DNA damage response) and sought effects of 5-ASA on ex vivo cultured biopsies and cultured rectal cancer cells. RESULTS: DUOX2 with maturation partner DUOXA2 forms the predominant system for H2O2 production in human colon and is upregulated in active colitis. DUOX2 in situ is exclusively epithelial, varies between and within individual crypts, and increases near inflammation. 8-OHdG and γH2AX were observed in damaged crypt epithelium. 5-ASA upregulated DUOX2 and DUOXA2 levels in the setting of active versus quiescent disease and altered DUOX2 expression in cultured biopsies. Ingenuity pathway analysis confirmed that inflammation status and 5-ASA increase expression of DUOX2 and DUOXA2. An epithelial cell model confirmed that cultured cancer cells expressed DUOX protein and produced H2O2 in response to hypoxia and 5-ASA exposure. CONCLUSIONS: Both DUOX2 and DUOXA2 expression are involved specifically in inflammation and are regulated on a crypt-by-crypt basis in ulcerative colitis tissues. Synergy between inflammation, hypoxia, and 5-ASA to increase H2O2 production could explain how 5-ASA supports innate defense, although potentially increasing the burden of DNA damage.


Assuntos
Colite Ulcerativa/patologia , Neoplasias do Colo/patologia , Peróxido de Hidrogênio/metabolismo , Proteínas de Membrana/metabolismo , Mesalamina/farmacologia , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adenoma/tratamento farmacológico , Adenoma/metabolismo , Adenoma/patologia , Anti-Inflamatórios não Esteroides/farmacologia , Western Blotting , Células Cultivadas , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Oxidases Duais , Imunofluorescência , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Hibridização In Situ , Inflamação/metabolismo , Inflamação/patologia , Proteínas de Membrana/genética , NADPH Oxidases/genética , Oxidantes/metabolismo , Oxirredução , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Int J Cancer ; 130(5): 1082-92, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21455990

RESUMO

Aberrant DNA methylation, microsatellite instability (MSI) and chromosomal instability (CIN) are well-characterised molecular features of sporadic colorectal cancers (CRCs). In addition to CpG island methylator phenotype (CIMP) associated with MSI, an intermediate methylation subgroup is also a feature of non-MSI cancers. A large proportion of CRCs have no evidence of either MSI or CIN, here called Microsatellite and Chromosomal Stable (MACS), and require their methylation profile to be established. The clinical and molecular features of 170 sporadic CRC patients were investigated and stratified into MSI, CIN and MACS groups. MACS were most often found in the left colon and had a significantly lower BRAF mutation frequency (p < 0.001) compared with MSI. MACS had better survival [hazard ratio (HR) = 0.244, p = 0.017] compared with CIN, but were similar to MSI. The methylation status of 1,505 CpG loci from cancer-related genes was analysed in a subset of CRCs (n = 44 normal-tumour pairs) and compared with CIN, MSI and MACS status. Using two-way hierarchical clustering, three subgroups were identified, which associated with CIN, MSI and MACS status. Using significance analysis of microarray, 16 CpG loci demonstrating methylation changes associated with MACS were identified. A combination of six loci identified MACS with 81% sensitivity and 93% specificity. This result now requires independent validation. Hypomethylation of a CpG locus within the sonic hedgehog (SHH) promoter correlated with increased gene expression and was associated significantly with MACS cancers. In conclusion, we propose that MACS have distinct clinicopathological features and can be distinguished from other CRCs by a specific set of methylation loci.


Assuntos
Instabilidade Cromossômica , Neoplasias Colorretais/genética , Metilação de DNA , Instabilidade de Microssatélites , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/genética
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