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Inflammasomes have recently been implicated in the pathogenesis of several chronic inflammatory disorders, such as diabetes and obesity. The aim of this meta-analysis was to investigate the possible role of the NLRP3 inflammasome in obesity and polycystic ovarian syndrome (PCOS). A comprehensive search of electronic databases was conducted to identify studies investigating NLRP3 its related components (Caspase 1, ASC and IL-1ß) in adipose tissue and/or blood from obese individuals compared to non-obese controls. Another search was conducted for studies investigating NLRP3 in PCOS women and animal models. The ssearched databases included Medline, EMBASE, Cochrane Library, PubMed, Clinicaltrials.gov, the EU Clinical Trials Register and the WHO International Clinical Trials Register. The quality and risk of bias for the included articles were assessed using the modified Newcastle-Ottawa scale. Data were extracted and pooled using RevMan software for the calculation of the standardized mean difference (SMD) and 95% confidence interval (CI). Twelve eligible studies were included in the obesity systematic review and nine in the PCOS review. Of the obesity studies, nine (n = 270) were included in the meta-analysis, which showed a significantly higher adipose tissue NLRP3 gene expression in obese (n = 186) versus non-obese (n = 84) participants (SMD 1.07; 95% CI, 0.27, 1.87). Pooled analysis of adipose tissue IL-1ß data from four studies showed significantly higher IL-1ß gene expression levels in adipose tissue from 88 obese participants versus 39 non-obese controls (SMD 0.56; 95% CI, 0.13, 0.99). Meta-analysis of adipose tissue ASC data from four studies showed a significantly higher level in obese (n = 109) versus non-obese (n = 42) individuals (SMD 0.91, 95% CI, 0.30, 1.52). Of the nine PCOS articles, three were human (n = 185) and six were animal studies utilizing PCOS rat/mouse models. All studies apart from one article consistently showed upregulated NLRP3 and its components in PCOS women and animal models. In conclusion, obesity and PCOS seem to be associated with upregulated expression of NLRP3 inflammasome components. Further research is required to validate these findings and to elucidate the role of NLRP3 in obesity and PCOS.
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Inflamassomos , Síndrome do Ovário Policístico , Camundongos , Humanos , Feminino , Ratos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Síndrome do Ovário Policístico/metabolismo , Obesidade/metabolismo , Tecido Adiposo/metabolismoRESUMO
Sterile inflammation may be initiated by molecules in the host organism that signal "damage" or "danger" also known as danger-associated molecular pattern (DAMPs). In pre-eclampsia (PE), a variety of DAMPs may be involved in the etiology or exacerbation of the disorder. Adenosine 5'-triphosphate (ATP) is a key intracellular energy molecule as well as a ligand for purinergic receptors. In humans, under physiological conditions, extracellular ATP (eATP) levels are distinctly low, but can rise to several hundred fold when cells become injured, stressed, or even necrotic. This often initiates a sterile inflammatory response with eATP acting as a DAMP. Extracellular ATP and its derivative nucleotides synthetized by endonucleotidases exhibit many of their effects through purinergic receptors, via inflammatory cascades and the production of proinflammatory molecules. This is clearly seen in the P2X7 gated receptor, which is linked to release of cytokines of the interleukin-1 family. Considering its fundamental role in innate immunity, an imbalance of P2X7 receptor activation may lead to deleterious effects in the coordination of placental vessel tone via the synthesis of various proinflammatory cytokines. This review explores the implication of DAMPs, specifically ATP and uric acid in the inflammation associated with PE.
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Trifosfato de Adenosina/metabolismo , Pré-Eclâmpsia/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Transdução de Sinais , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Ácido Úrico/metabolismoRESUMO
INTRODUCTION: Pre-eclampsia is a hypertensive gestational disorder that affects approximately 5% of all pregnancies. OBJECTIVES: As the pathophysiological processes of pre-eclampsia are still uncertain, the present case-control study explored underlying metabolic processes characterising this disease. METHODS: Maternal peripheral plasma samples were collected from pre-eclamptic (n = 32) and healthy pregnant women (n = 35) in the third trimester. After extraction, high-resolution mass spectrometry-based untargeted metabolomics was used to profile polar and apolar metabolites and the resulting data were analysed via uni- and multivariate statistical approaches. RESULTS: The study demonstrated that the metabolome undergoes substantial changes in pre-eclamptic women. Amongst the most discriminative metabolites were hydroxyhexacosanoic acid, diacylglycerols, glycerophosphoinositols, nicotinamide adenine dinucleotide metabolites, bile acids and products of amino acid metabolism. CONCLUSIONS: The putatively identified compounds provide sources for novel hypotheses to help understanding of the underlying biochemical pathology of pre-eclampsia.
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Metaboloma/fisiologia , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Metabolômica/métodos , Pré-Eclâmpsia/sangue , GravidezRESUMO
BACKGROUND: Oestrogen receptors (ER) have a well-established role to the initiation, progression and regulation of responses to treatment of breast, prostate, and lung cancers. Previous data indicates altered ER expression in oesophageal cancers (OC). However the role of ER subtypes and ER specific inhibitors in the regulation of OC progression remains unclear. This study sought to assess levels of ERα and ERß in OC. The effects of highly selective ER antagonists on cell proliferation and apoptosis in two OC adenocarcinoma cell lines was also studied. METHODS: ERα and ERß expression profiling in paired normal oesophageal mucosa and tumour tissues (n = 34; adenocarcinoma n = 28; squamous cell carcinoma n = 6) was performed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Correlation between levels of ER with the clinico-pathological features for OC was determined. The effect of selective ER antagonists on proliferation of OE33 and OE19 OC cell lines was studied. RESULTS: ERα and ERß mRNA expression was significantly higher (p < 0.05) in tumour tissues relative to their paired normal mucosa and correlated inversely with survival outcome (p < 0.05). Upregulation of ERα mRNA correlated with higher pathological T-stage (p < 0.05) and lymph node metastasis (p < 0.05) while ERß mRNA upregulation correlated with positive vascular invasion (p < 0.05). A significant concentration-dependent inhibition of proliferation in OE33 and OE19 cell lines was induced by a highly-selective ERα antagonist (MPP) and an ERß specific antagonist (PHTPP) (p < 0.05). Moreover, anti-oestrogens induced cell death through stimulation of apoptotic caspase activity. CONCLUSION: These findings indicate that the ER system is involved in OC progression and thus may provide a novel target for the treatment of OC.
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Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Antagonistas do Receptor de Estrogênio/administração & dosagem , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Proliferação de Células/efeitos dos fármacos , Intervalo Livre de Doença , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genéticaRESUMO
Maternal obesity is associated with prolonged and dysfunctional labour and emergency caesarean section, but the mechanisms are unknown. The present study investigated the effects of an adiposity-inducing high-fat, high-cholesterol (HFHC) diet on uterine contractile-associated protein (CAP) expression and ex vivo uterine contractility in term non-labouring (TNL) and term labouring (TL) rats. Female rats were fed either control chow (CON n=20) or HFHC (n=20) diet 6 weeks before conception and during pregnancy. On gestational day 21 (TNL) or day 22 (TL) CON and HFHC (n=10) rats were killed to determine plasma cholesterol, triacylglycerol and progesterone concentrations and collection of myometrium for contractility studies and expression of CAPs caveolin-1 (Cav-1), connexin-43 (CX-43) and it's phosphorylated form (pCX-43), oxytocin receptor (OXTR) and cyclooxygenase-2 (COX-2). HFHC feeding increased visceral fat (P≤0.001), plasma cholesterol (P≤0.001) and triacylglycerol (P=0.039) concentrations. Stage of labour effected uterine expression of CAV-1 (P<0.02), pCX43 and COX-2 (both P<0.03). CAV-1 and pCX43 decreased but COX-2 increased with parturition. Significant diet- and labour-stage interactions were evident for CX-43 and pCX43 (P<0.03 and P<0.004 respectively). CX-43 decreased with TL in HFHC animals but was unaltered in CON. pCX-43 fell with labour in CON but remained high in HFHC. OXTR expression was significantly higher in HFHC compared with CON animals (P<0.03). Progesterone was higher in HFHC rats at term (P<0.014) but fell significantly with labour to similar concentrations as CON. Contractility studies identified synchronous contractions of stable amplitude in lean animals, but unstable asynchronous contractions with obesity. Uterine dose response to oxytocin was blunted during labour in HFHC rats with a log EC50 of -8.84 compared with -10.25 M in CON for integral activity (P<0.05). In conclusion, our adiposity model exhibits adverse effects on contractile activity during labour that can be investigated further to unravel the mechanisms causing uterine dystocia in obese women.
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Caveolina 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Obesidade/metabolismo , Complicações na Gravidez/metabolismo , Contração Uterina , Útero/metabolismo , Animais , Colesterol na Dieta/efeitos adversos , Conexina 43/metabolismo , Proteínas Contráteis/metabolismo , Dieta Hiperlipídica/efeitos adversos , Dinoprosta , Modelos Animais de Doenças , Feminino , Lipídeos/sangue , Tamanho da Ninhada de Vivíparos , Masculino , Obesidade/etiologia , Ocitocina , Gravidez , Progesterona/sangue , Ratos Wistar , Aumento de PesoRESUMO
The onset of parturition is associated with a number of proinflammatory mediators that are themselves regulated by the nuclear factor κB (NF-κB) family of transcription factors. In this context, we previously reported that the RelA NF-κB subunit represses transcription and mRNA expression of the proquiescent Gαs gene in human myometrial cells following stimulation with the proinflammatory cytokine TNF. In the present study, we initially defined the functional consequence of this on myometrial contractility. Here we show that, contrary to our initial expectations, TNF did not induce myometrial contractility but did inhibit the relaxation produced by the histone deacetylase inhibitor trichostatin A, an effect that in turn was abolished by the NF-κB inhibitor N(4)-[2-(4-phenoxyphenyl)ethyl]-4,6-quinazolinediamine. This result suggested a role for TNF in regulating Gαs expression via activating NF-κB and modifying histone acetylation associated with the promoter region of the gene. In this context, we show that the -837 to -618 region of the endogenous Gαs promoter is occupied by cAMP-response element-binding protein (CREB), Egr-1, and Sp1 transcription factors and that CREB-binding protein (CBP) transcriptional complexes form within this region where they induce histone acetylation, resulting in increased Gαs expression. TNF, acting via NF-κB, did not change the levels of CREB, Sp1, or Egr-1 binding to the Gαs promoter, but it induced a significant reduction in the level of CBP. This was associated with increased levels of histone deacetylase-1 and surprisingly an increase in H4K8 acetylation. The latter is discussed herein.
Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/fisiologia , Complexos Multiproteicos/metabolismo , Proteínas Musculares/metabolismo , Miométrio/metabolismo , Elementos de Resposta/fisiologia , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Acetilação/efeitos dos fármacos , Adolescente , Adulto , Células Cultivadas , Feminino , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histonas/genética , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Complexos Multiproteicos/genética , Proteínas Musculares/genética , Miométrio/citologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/metabolismo , Contração Uterina/efeitos dos fármacos , Contração Uterina/fisiologiaRESUMO
(1) Background: Current evidence indicates that women with polycystic ovarian syndrome (PCOS) undergoing in vitro fertilization (IVF) have an increased likelihood of adverse pregnancy outcomes. The objective of this systematic review was to clarify the role of a PCOS-related high body mass index (BMI) in these unfavourable pregnancy outcomes. (2) Methods: A comprehensive search of electronic databases was conducted to identify studies investigating the impact of high BMI on pregnancy outcomes in women with PCOS undergoing IVF. RevMan software (v5.4) was used to calculate the odds ratio (OR) and 95% confidence interval (CI). (3) Results: Nineteen eligible studies (n = 7680) were identified, including 16 retrospective cohort studies (n = 6934), two prospective cohort studies (n = 525), and one cross-sectional study (n = 221). Pooled analysis showed significantly higher odds of clinical pregnancy (OR, 1.16 [95% CI, 1.04-1.29]; z = 2.73; p = 0.006; I2 = 30%) and livebirths (OR, 1.88 [95% CI, 1.56-2.27]; z = 6.54; p < 0.0001; I2 = 55%) in women with PCOS with a normal versus a high BMI. Meta-analysis showed significantly increased odds of miscarriages in women with PCOS with a high versus a normal BMI (OR, 0.76 [95% CI, 0.60-0.95]; z = 2.42; p = 0.02; I2 = 53%). Pooled analysis of three studies (n = 993) showed significantly higher ORs of gestational diabetes mellitus (OR 3.96 [95% CI 1.62-9.68]; z = 3.01; p = 0.003; I2 = 58%) and gestational hypertension (OR 2.16 [95% CI 1.32-3.54]; z = 3.05; p = 0.002; I2 = 68%) in women with PCOS with a high versus a normal BMI. Meta-analysis of three studies reported significantly greater odds of a caesarean section for women with PCOS with a high versus a normal BMI (OR 0.45 [95% CI 0.29-0.69]; z = 3.66; p = 0.0003; I2 = 0%). (4) Conclusions: The increased likelihood of adverse pregnancy outcomes observed in women with PCOS undergoing IVF seems to be attributable to a PCOS-related high BMI.
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Non-communicable diseases (NCDs) claim 74% of global lives, disproportionately affecting lower and middle-income countries like Pakistan. NCDs may increase the risk of preterm birth (PTB), caesarean section (CS), and low birthweight. This study aims to determine whether the high prevalence of NCDs in Pakistan play a role in the high rates of preterm births, and CS. This retrospective cohort study from Aga Khan University Hospital, Pakistan, investigated effects of pre-existing NCDs on pregnancy outcomes of 817 pregnant women. Medical records were used to generate odds ratios for the risk of PTB, labour outcome and birthweight in women with type 1 and type 2 diabetes, hypertension, asthma and thyroid disorders. Multinomial logistic regression and general linear models were used to adjust for confounding variables using IBM SPSS Statistics (v27). Type 2 diabetes significantly increased the risk of PTB and elective CS (both P < 0.05). Elective CS was significantly increased by hypertension and asthma (both, P < 0.05). Surprisingly, asthma halved the risk of PTB (P < 0.05), while type 1 diabetes significantly increased birthweight from 2832 to 3253g (P < 0.001). In conclusion, pre-existing NCDs increase the risk of negative pregnancy outcomes, including PTB, elective CS and birthweight. Asthma, however reduced PTB and justifies further investigation.
Assuntos
Asma , Diabetes Mellitus Tipo 2 , Hipertensão , Doenças não Transmissíveis , Nascimento Prematuro , Gravidez , Humanos , Feminino , Recém-Nascido , Resultado da Gravidez , Cesárea , Peso ao Nascer , Nascimento Prematuro/epidemiologia , Paquistão/epidemiologia , Doenças não Transmissíveis/epidemiologia , Estudos Retrospectivos , Asma/epidemiologia , Hipertensão/epidemiologiaRESUMO
The transition metal cadmium (Cd) is toxic to humans and can induce cellular redox stress and inflammation. Cd is a recognized carcinogen, but the molecular mechanisms associated with its genotoxicity and carcinogenicity are not defined. Therefore, a systematic review was undertaken to examine the scientific literature that has covered the molecular mechanism of Cd genotoxicity and its relationship to cellular redox stress and inflammation. An electronic database search of PubMed, Scopus, and the Web of Science Core Collection was conducted to retrieve the studies that had investigated if Cd genotoxicity was directly linked to the induction of redox stress and inflammation. Studies included exposure to Cd via in vitro and in vivo routes of administration. Of 214 publications retrieved, 10 met the inclusion criteria for this review. Preclinical studies indicate that Cd exposure causes the induction of reactive oxygen species (ROS) and, via concomitant activity of the transcription factor NF-κß, induces the production of pro-inflammatory cytokines and a cytokine profile consistent with the induction of an allergic response. There is limited information regarding the impact of Cd on cellular signal transduction pathways, and the relationship of this to genotoxicity is still inconclusive. Nevertheless, pre-incubation with the antioxidants, N-acetylcysteine or sulforaphane, or the necroptosis inhibitor, necrostatin-1, reduces Cd toxicity; indicative that these agents may be a beneficial treatment adjunct in cases of Cd poisoning. Collectively, this review highlights that Cd-induced toxicity and associated tissue pathology, and ultimately the carcinogenic potential of Cd, may be driven by redox stress and inflammatory mechanisms.
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Background: Currently, the primary strategy for addressing polycystic ovarian syndrome (PCOS) involves lifestyle modifications, with a focus on weight loss. The purpose of this meta-analysis was to assess the impact of weight loss through dietary interventions on inflammatory status and hyperandrogenism in PCOS women. Methods: A comprehensive search was conducted to identify randomised controlled trials (RCTs) and cohort studies assessing the impact of diet-induced weight loss on circulating inflammatory markers (CRP, IL-6, IL-1ß, TNF-α), androgens (testosterone, androstenedione), SHBG, and luteinising hormone (LH) in PCOS women. The quality and risk of bias of the included studies were assessed using the Cochrane Collaboration's tool for RCTs and the Newcastle-Ottawa Scale for cohort studies. Data were entered into RevMan software v5.9 for the calculation of standard mean difference (SMD) and the 95% confidence interval (95%CI) of circulating inflammatory markers, androgens, and LH between baseline and post-weight loss values. Results: Eleven studies (n = 323) were eligible for the systematic review, of which nine (n = 286) were included in the meta-analysis. Pooled analysis of data revealed a statistically significant decrease in circulating CRP (SMD 0.39, 95%CI 0.22, 0.56; 9 studies, n = 286), IL-6 (SMD 0.37, 95%Cl, 0.12, 0.61; 3 Studies, n = 140), TNF-α (SMD 0.30, 95%Cl, 0.07, 0.53; 4 Studies, n = 162), androstenedione (SMD 0.36, 95%Cl, 0.13, 0.60; 4 studies, n = 147) and LH (SMD 0.30, 95% Cl, 0.09, 0.51; 5 studies, n = 197) after weight loss compared to baseline levels among PCOS women. A meta-analysis of five studies (n = 173) showed a statistically significant increase in circulating SHBG after weight loss compared to baseline levels (SMD -0.43, 95%Cl, -0.65, -0.21). Conclusions: These findings suggest that weight loss induced by dietary interventions seems to improve PCOS-related chronic inflammation and hyperandrogenism. The possible causative relationship between the improvement in inflammation and hyperandrogenism remains to be determined.
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The human endometrial epithelium is pivotal to menstrual cycle progression, implantation and early pregnancy. Endometrial function is directly regulated by local factors that include pH, oxygen tension and ion concentrations to generate an environment conducive to fertilization. A superfamily of potassium channels characterized by two-pore domains (K2P) and encoded by KCNK genes is implicated in the control of the cell resting membrane potential through the generation of leak currents and modulation by various physicochemical stimuli. The aims of the study were to determine the expression and function of K2P channel subtypes in proliferative and secretory phase endometrium obtained from normo-ovulatory women and in an endometrial cancer cell line. Using immunochemical methods, real-time qRT-PCR proliferation assays and electrophysiology. Our results demonstrate mRNA for several K2P channel subtypes in human endometrium with molecular expression of TREK-1 shown to be higher in proliferative than secretory phase endometrium (P < 0.001). The K2P channel blockers methanandamide, lidocaine, zinc and curcumin had antiproliferative effects (P < 0.01) in an endometrial epithelial cancer cell line indicating a role for TASK and TREK-1 channels in proliferation. Tetraethylammonium- and 4-aminopyridine-insensitive outwards currents were inhibited at all voltages by reducing extracellular pH from 7.4 to 6.6. Higher expression of TREK-1 expression in proliferative phase endometrium may, in part, underlie linked to increased cell division. The effects of pH and a lack of effect of non-specific channel blockers of voltage-gated potassium channels imply a role for K2P channels in the regulation of human endometrial function.
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Endométrio/fisiologia , Células Epiteliais/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , RNA Mensageiro/metabolismo , Adulto , Ácidos Araquidônicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/citologia , Células Epiteliais/citologia , Feminino , Regulação da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Lidocaína/farmacologia , Potenciais da Membrana , Ciclo Menstrual/fisiologia , Proteínas do Tecido Nervoso/genética , Ovulação/fisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Domínios Poros em Tandem/genética , Cultura Primária de Células , RNA Mensageiro/genéticaRESUMO
Maternal obesity is associated with increased risk of prolonged and dysfunctional labor and emergency caesarean section. To elucidate the mechanisms behind the associated uterine dystocia, a translational animal model is required. Our previous work identified that exposure to a high-fat, high-cholesterol (HFHC) diet to induce obesity down-regulates uterine contractile associated protein expression and causes asynchronous contractions ex vivo. This study aims to investigate the impact of maternal obesity on uterine contractile function in vivo using intrauterine telemetry surgery. Virgin female Wistar rats were fed either a control (CON, n = 6) or HFHC (n = 6) diet for 6 weeks prior to conception, and throughout pregnancy. On Day 9 of gestation, a pressure-sensitive catheter was surgically implanted aseptically within the gravid uterus. Following 5 days recovery, intrauterine pressure (IUP) was recorded continuously until delivery of the 5th pup (Day 22). HFHC induced obesity led to a significant 1.5-fold increase in IUP (p = 0.026) and fivefold increase in frequency of contractions (p = 0.013) relative to CON. Determination of the time of labor onset identified that HFHC rats IUP (p = 0.046) increased significantly 8 h prior to 5th pup delivery, which contrasts to CON with no significant increase. Myometrial contractile frequency in HFHC rats significantly increased 12 h prior to delivery of the 5th pup (p = 0.023) compared to only 3 h in CON, providing evidence that labor in HFHC rats was prolonged by 9 h. In conclusion, we have established a translational rat model that will allow us to unravel the mechanism behind uterine dystocia associated with maternal obesity.
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Distocia , Hipercolesterolemia , Obesidade Materna , Feminino , Humanos , Gravidez , Ratos , Animais , Cesárea , Ratos Wistar , Parto , Obesidade/etiologia , Proteínas ContráteisRESUMO
Premature delivery remains a serious risk factor in pregnancy, with currently licensed tocolytics unable to offer significant improvement in neonatal outcome. Further understanding of the regulators of uterine contractility is required to enable the development of novel and more effective tocolytic therapies. The transglutaminase family is a class of calcium-dependent, transamidating enzymes, of which tissue transglutaminase 2 is a multifunctional enzyme with roles in cell survival, migration, adhesion, and contractility. The aim of the present study was to investigate the role of this enzyme in regulating the contractility of pregnant human myometrium. Tissue strips from biopsy samples obtained at elective cesarean section were either allowed to contract spontaneously or induced to contract with oxytocin, phenylephrine, or bradykinin. Activity integrals, used to measure contractile activity, were taken following cumulative additions of the reversible, polyamine transglutaminase inhibitors cystamine and mono-dansylcadaverine and the irreversible, site-specific transglutaminase inhibitors N-benzyloxycarbonyl-l-phenylalanyl-6-dimethylsulfonium-5-oxo-L-norleucine and 1,3-dimethyl-2[(oxopropyl)thio]imidazolium. The ability of cystamine and mono-dansylcadaverine to affect oxytocin-mediated calcium mobilization within primary cultured myometrial cells was also measured utilizing a calcium indicator. All inhibitors attenuated myometrial contractions in a concentration-dependent manner independent of the method of contraction stimulus. Similarly cultured myometrial cells preincubated with cystamine and mono-dansylcadaverine displayed an altered calcium response to oxytocin stimulation. Our findings demonstrate a potential role for tissue transglutaminase 2 in regulating uterine contractility in pregnant human myometrium that may be associated with the calcium signaling cascade required for contraction.
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Inibidores Enzimáticos/farmacologia , Tocolíticos/farmacologia , Transglutaminases/antagonistas & inibidores , Contração Uterina/efeitos dos fármacos , Bradicinina/farmacologia , Cadaverina/análogos & derivados , Cadaverina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cistamina/farmacologia , Feminino , Proteínas de Ligação ao GTP , Humanos , Imidazóis/farmacologia , Técnicas In Vitro , Miométrio/efeitos dos fármacos , Miométrio/fisiologia , Norleucina/análogos & derivados , Norleucina/farmacologia , Trabalho de Parto Prematuro/prevenção & controle , Ocitocina/farmacologia , Fenilefrina/farmacologia , Gravidez , Proteína 2 Glutamina gama-Glutamiltransferase , Tocólise , Transglutaminases/fisiologia , Contração Uterina/fisiologiaRESUMO
BACKGROUND: The voltage gated potassium (K+) channels Eag and HERG have been implicated in the pathogenesis of various cancers, through association with cell cycle changes and programmed cell death. The role of these channels in the onset and progression of ovarian cancer is unknown. An understanding of mechanism by which Eag and HERG channels affect cell proliferation in ovarian cancer cells is required and therefore we investigated their role in cell proliferation and their effect on the cell cycle and apoptosis of ovarian cancer cells. METHODS: The presence of Eag and HERG was determined in SK-OV-3 cells using immunofluorescence and western blotting. The effect of the Eag blockers (imipramine and clofilium) and HERG blockers (E-4031 and ergtoxin) on cell proliferation was assessed using the MTS assay with further investigation of their role in the cell cycle and apoptosis determined by flow cytometry. RESULTS: Eag and HERG channels were present in the cytoplasm and nuclei of SK-OV-3 cells. There was significant inhibition of proliferation of SK-OV-3 cells by imipramine (P < 0.001) and ergtoxin (P < 0.05) at 72 hours of culture. Incubation of cells with ergtoxin led to the accumulation of cells in the S and G2/M phase, while cells accumulated in S phase after incubation with E-4031, with no effect on apoptosis. Imipramine did not affect the cell cycle but increased the proportion of SK-OV-3 cells undergoing early apoptosis. CONCLUSION: Both Eag and HERG channels are expressed in SK-OV-3 ovarian cancer cells and have a role in cell proliferation. HERG channels affect the cell cycle while Eag channels are implicated in the inhibition of apoptosis of ovarian cancer cells. The family of Eag channels may represent a new therapeutic target for the treatment of ovarian cancer.
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BACKGROUND: Human oesophageal carcinoma is considered to be one of the most aggressive malignancies and has a very poor prognosis. The incidence of oesophageal cancer shows a gender bias and is higher in males compared with females, the ratio between males and females varying from 3:1 to 7:1. This sex ratio is not entirely attributable to differences in the prevalence of known risk factors between the sexes. The potential role of oestrogen receptors (ER) in oesophageal cancer has been debated for several years but the significance of the receptors in this cancer remains unknown. Most of the work has been based on immunohistochemistry and has not been validated with other available techniques. The inconsistencies in the published literature on the link between ER expression and oesophageal cancer warrant a thorough evaluation of the potential role of ERs in this malignancy. Even the expression of the two ER isoforms, ERalpha and ERbeta, and its implications for outcome of treatments in histological subtypes of oesophageal tumours is ill defined. The aim of this article is to provide updated information from the available literature on the current status of ER expression in oesophageal cancer and to discuss its potential therapeutic role. METHODS AND RESULTS: We performed a comprehensive literature search and analysed the results regarding ER expression in oesophageal tumours with special emphasis on expression of different oestrogen receptors and the role of sex hormones in oesophageal cancer. This article also focuses on the significance of the two main ER subtypes and mechanisms underlying the presumed male predominance of this disease. CONCLUSION: We postulate that differential oestrogen receptor status may be considered a biomarker of poor clinical outcome based on tissue dedifferentiation or advanced stage of the disease. Further, if we can establish the importance of oestrogen and its receptors in the context of oesophageal cancer, then this may lead to a new future direction in the management of this malignancy.
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Neoplasias Esofágicas/metabolismo , Receptores de Estrogênio/metabolismo , Feminino , Humanos , MasculinoRESUMO
Voltage gated potassium channels have been extensively studied in relation to cancer. In this review, we will focus on the role of two potassium channels, Ether à-go-go (Eag), Human ether à-go-go related gene (HERG), in cancer and their potential therapeutic utility in the treatment of cancer. Eag and HERG are expressed in cancers of various organs and have been implicated in cell cycle progression and proliferation of cancer cells. Inhibition of these channels has been shown to reduce proliferation both in vitro and vivo studies identifying potassium channel modulators as putative inhibitors of tumour progression. Eag channels in view of their restricted expression in normal tissue may emerge as novel tumour biomarkers.
Assuntos
Antineoplásicos/uso terapêutico , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Animais , Canal de Potássio ERG1 , Humanos , Neoplasias/metabolismo , Neoplasias/patologiaRESUMO
BACKGROUND: Elevated pre-operative neutrophil: lymphocyte ratio (NLR) has been identified as a predictor of survival in patients with hepatocellular and colorectal cancer. The aim of this study was to examine the prognostic value of an elevated preoperative NLR following resection for oesophageal cancer. METHODS: Patients who underwent resection for oesophageal carcinoma from June 1997 to September 2007 were identified from a local cancer database. Data on demographics, conventional prognostic markers, laboratory analyses including blood count results, and histopathology were collected and analysed. RESULTS: A total of 294 patients were identified with a median age at diagnosis of 65.2 (IQR 59-72) years. The median pre-operative time of blood sample collection was three days (IQR 1-8). The median neutrophil count was 64.2 x 10-9/litre, median lymphocyte count 23.9 x 10-9/litre, whilst the NLR was 2.69 (IQR 1.95-4.02). NLR did not prove to be a significant predictor of number of involved lymph nodes (Cox regression, p = 0.754), disease recurrence (p = 0.288) or death (Cox regression, p = 0.374). Furthermore, survival time was not significantly different between patients with high (>or= 3.5) or low (< 3.5) NLR (p = 0.49). CONCLUSION: Preoperative NLR does not appear to offer useful predictive ability for outcome, disease-free and overall survival following oesophageal cancer resection.
Assuntos
Adenocarcinoma/mortalidade , Carcinoma de Células Escamosas/mortalidade , Neoplasias Esofágicas/mortalidade , Linfócitos/citologia , Neutrófilos/citologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Glioblastoma multiforme (GBM) is a lethal brain cancer with an average survival of 14-15 months even with exhaustive treatment. High grade gliomas (HGG) represent the leading cause of CNS cancer-related death in children and adults due to the aggressive nature of the tumour and limited treatment options. The scarcity of treatment available for GBM has opened the field to new modalities such as electrotherapy. Previous studies have identified the clinical benefit of electrotherapy in combination with chemotherapeutics, however the mechanistic action is unclear. Increasing evidence indicates that not only are ion channels key in regulating electrical signaling and membrane potential of excitable cells, they perform a crucial role in the development and neoplastic progression of brain tumours. Unlike other tissue types, neural tissue is intrinsically electrically active and reliant on ion channels and their function. Ion channels are essential in cell cycle control, invasion and migration of cancer cells and therefore present as valuable therapeutic targets. This review aims to discuss the role that ion channels hold in gliomagenesis and whether we can target and exploit these channels to provide new therapeutic targets and whether ion channels hold the mechanistic key to the newfound success of electrotherapies.
RESUMO
Evidence suggests that sub-optimal maternal nutrition has implications for the developing offspring. We have previously shown that exposure to a low-protein diet during gestation was associated with upregulation of genes associated with cholesterol transport and packaging within the placenta. This study aimed to elucidate the effect of altering maternal dietary linoleic acid (LA; omega-6) to alpha-linolenic acid (ALA; omega-6) ratios as well as total fat content on placental expression of genes associated with cholesterol transport. The potential for maternal body mass index (BMI) to be associated with expression of these genes in human placental samples was also evaluated. Placentas were collected from 24 Wistar rats at 20-day gestation (term = 21-22-day gestation) that had been fed one of four diets containing varying fatty acid compositions during pregnancy, and from 62 women at the time of delivery. Expression of 14 placental genes associated with cholesterol packaging and transfer was assessed in rodent and human samples by quantitative real time polymerase chain reaction. In rats, placental mRNA expression of ApoA2, ApoC2, Cubn, Fgg, Mttp and Ttr was significantly elevated (3-30 fold) in animals fed a high LA (36% fat) diet, suggesting increased cholesterol transport across the placenta in this group. In women, maternal BMI was associated with fewer inconsistent alterations in gene expression. In summary, sub-optimal maternal nutrition is associated with alterations in the expression of genes associated with cholesterol transport in a rat model. This may contribute to altered fetal development and potentially programme disease risk in later life. Further investigation of human placenta in response to specific dietary interventions is required.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica no Desenvolvimento , Fenômenos Fisiológicos da Nutrição Materna/genética , Obesidade/complicações , Placenta/metabolismo , Adulto , Animais , Colesterol/metabolismo , Modelos Animais de Doenças , Feminino , Desenvolvimento Fetal/genética , Perfilação da Expressão Gênica , Humanos , Ácido Linoleico/administração & dosagem , Ácido Linoleico/efeitos adversos , Obesidade/metabolismo , Gravidez , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Ácido alfa-Linolênico/administração & dosagem , Ácido alfa-Linolênico/efeitos adversosRESUMO
Cytochrome P-450 (CYP450) enzymes of the CYP2 and -4 family in humans metabolize arachidonic acid to generate bioactive epoxyeicosatrienenoic acids (EETs) and hydroxyeicosatetrenoic acids (HETEs). We report significantly higher levels of CYP 2J2 protein expression following the onset of labor (n = 6, P < 0.05), implying increased EET-generating capacity within the uterus. Myometrial relaxation to 8,9-EET and 5,6-EET was observed, with the latter being inhibited by preincubation with 1 muM paxilline and is supported by whole cell recordings showing a modest effect of 5,6-EET on myometrial outward-current density (n = 4, P < 0.05). Only 5,6-EET of the EETs tested affected vascular reactivity (n = 6). Both 12- and 20-HETE (n = 5-6) caused vasoconstriction of partially depolarized blood vessels, with glibenclamide (n = 5) enhancing the effect of 12-HETE alone. Our findings signify a role for CYP2C9/19, -2J2, and -4A11/22 in late pregnancy, possibly related to the synthesis of lipid metabolites and downstream effects on vascular remodeling in the term pregnant uterus. The presence of CYP4A11/22 and their resultant procontractile metabolites could argue either a role in the control and initiation of labor and/or modification of the vascular delivery system to influence blood flow to the laboring uterus. The differential effects of the EETs and HETEs in the pregnant human uterus identify the CYP pathway as a novel modulator of myometrial and vascular physiology during late pregnancy.