RESUMEN
AIM: The aim of the present experimental study was to assess the tocolytic effect of eicosanoids on myometrium from non-pregnant and pregnant rats with or without an induced inflammatory condition. METHODS: Three hundred myometrial rings were obtained by median laparotomy from 50 Sprague-Dawley rats divided into three groups: (i) non-pregnant (n = 15); (ii) pregnant in absence (n = 20); or (iii) pregnant in presence (n = 15) of lipopolysaccharide treatment, timed at 22 days of pregnancy. Spontaneous contractile activities were compared by isometric tension measurements. The effects of epoxy- and hydroxyeicosanoids derived from arachidonic acid as well as specific enzyme inhibitors were assessed. Changes were expressed as percentage of basal activity by calculating the area under the curve as a function of drug concentration and compared to the effect of the vehicle. RESULTS: A decrease in contractile activity ranging 10-25% was observed upon addition of epoxy- and hydroxyeicosanoids. Increasing epoxyeicosanoid bioavailability by inhibiting their degradation induced a tocolytic effect in the non-pregnant group (20%) and in inflammation-induced condition (40%). There was a significant difference in reactivity between groups and pregnancy condition. Semiquantification of metabolic enzymes that produce (cytochrome P-450 epoxygenase) and degrade (soluble epoxide hydrolase) epoxyeicosanoids by western blot analysis revealed that these enzymes were mainly detected in the non-pregnant group. CONCLUSION: Eicosanoids can modify myometrial reactivity and their presence and effects are amplified in non-pregnant and in inflammation-induced condition. Our data suggest that in contrast to prostaglandins, epoxyeicosatrienoic acids are likely involved in the quiescence phase of parturition because they reduce the rhythmic contractile activity of uterine tissues in pregnant rats.
Asunto(s)
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Regulación hacia Abajo , Ácidos Hidroxieicosatetraenoicos/metabolismo , Modelos Biológicos , Miometrio/metabolismo , Mantenimiento del Embarazo , Contracción Uterina , Ácido 8,11,14-Eicosatrienoico/antagonistas & inhibidores , Ácido 8,11,14-Eicosatrienoico/metabolismo , Animales , Citocromo P-450 CYP2J2 , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Epóxido Hidrolasas/antagonistas & inhibidores , Epóxido Hidrolasas/metabolismo , Femenino , Ácidos Hidroxieicosatetraenoicos/antagonistas & inhibidores , Técnicas In Vitro , Miometrio/efectos de los fármacos , Miometrio/inmunología , Embarazo , Complicaciones del Embarazo/enzimología , Complicaciones del Embarazo/inmunología , Complicaciones del Embarazo/metabolismo , Ratas Sprague-Dawley , Contracción Uterina/efectos de los fármacos , Enfermedades Uterinas/enzimología , Enfermedades Uterinas/inmunología , Enfermedades Uterinas/metabolismoRESUMEN
AIM: To study the effect of blocking the inflammatory cascade with interleukin-6 receptor antibody (anti-IL-6R) on feto-maternal outcomes in a rat model. METHODS: Pregnant Sprague-Dawley rats (n = 38) were injected intraperitoneally (day 22) (control, anti-IL-6R 30 µg/kg, lipopolysaccharide [LPS] 250 µg/kg or 500 µg/kg alone or combined with anti-IL-6R) followed by preterm caesarian performed 12 h later. Resuscitated pups (n = 179) were given to surrogate mothers. Primary outcomes were maternal and pup mortality. RESULTS: Fifty percent of pregnant rats died after LPS 500 µg/kg + anti-IL-6R injection but none in other groups. Neonatal mortality at 24 h was 63% and 86% in LPS 500 µg/kg and LPS 500 µg/kg + anti-IL-6R groups, respectively (P < 0.05). Surviving pups in the latter group presented a severe growth deficit compared to the LPS 500 µg/kg group (P < 0.01) and showed no difference with controls for open field testing. Maternal cytokine analysis after LPS 500 µg/kg + anti-IL-6R injection showed a tendency for increased IL-1 production (P = 0.06). CONCLUSION: Paradoxically, the association of pregnancy, inflammation and anti-IL-6R increases the inflammatory effects of LPS.
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Corioamnionitis/metabolismo , Receptores de Interleucina-6/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Inyecciones Intraperitoneales , Lipopolisacáridos , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores de Interleucina-6/antagonistas & inhibidoresRESUMEN
The incidence of preterm birth is an increasing problem. Indomethacin, a non-specific cyclooxygenase inhibitor, has been largely used as tocolytic in the treatment of preterm labor. The aim of the present study was to assess a putative synergistic tocolytic effect between the inhibition of the production of prostanoids and stabilization of epoxides fatty acids, particularly arachidonate on spontaneous uterine contractile activity. The experimental work was performed on uterine biopsies from consenting women undergoing elective cesarean delivery at term. Isometric tension measurements were performed on fresh human myometrial strips. Contractile activities have been monitored upon individual and combined treatments of indomethacin, DDMS, an inhibitor of hydroxy-eicosanoids production and AUDA, an inhibitor of epoxy-eicosanoids degradation. Interestingly, a significant and consistent synergic effect was observed when indomethacin and AUDA were simultaneously added, raising the possibility of a combined clinical use of cyclooxygenase and sEH inhibitors in attempt to treat preterm labor.
Asunto(s)
Inhibidores de la Ciclooxigenasa/farmacología , Inhibidores Enzimáticos del Citocromo P-450 , Eicosanoides/biosíntesis , Epóxido Hidrolasas/antagonistas & inhibidores , Miometrio/efectos de los fármacos , Tocolíticos/farmacología , Contracción Uterina/efectos de los fármacos , Adamantano/análogos & derivados , Adamantano/farmacología , Adulto , Amidas/farmacología , Ácido Araquidónico/metabolismo , Cesárea , Ciclooxigenasa 2/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Sinergismo Farmacológico , Eicosanoides/antagonistas & inhibidores , Epóxido Hidrolasas/metabolismo , Femenino , Humanos , Indometacina/farmacología , Recién Nacido , Ácidos Láuricos/farmacología , Miometrio/metabolismo , Embarazo , Transducción de Señal/efectos de los fármacos , Sulfonas/farmacología , Contracción Uterina/metabolismo , Adulto JovenRESUMEN
BACKGROUND: Medical societies and funding agencies strongly recommend that patients be included as partners in research publications and grant applications. Although this "top-down" approach is certainly efficient at forcing this new and desirable type of collaboration, our past experience demonstrated that it often results in an ambiguous relationship as not yet well integrated into the cultures of either patients' or the researchers'. The question our group raised from this observation was: "How to generate a cultural shift toward a fruitful and long-lasting collaboration between patients and researchers? A "bottom-up" approach was key to our stakeholders. The overall objective was to build a trusting and bidirectional-ecosystem between patients and researchers. The specific objectives were to document: 1) the steps that led to the development of the first patient-partner strategic committee within a research center in the Province of Québec; 2) the committee's achievements after 3 years. METHODS: Eighteen volunteer members, 12 patient-partners and 6 clinician/institutional representatives, were invited to represent the six research themes of the Centre de recherche du CHU de Sherbrooke (CRCHUS) (Quebec, Canada). Information on the services offered by Committee was disseminated internally and to external partners. Committee members satisfaction was evaluated. RESULTS: From May 2017 to April 2020, members attended 29 scheduled and 6 ad hoc meetings and contributed to activities requiring over 1000 h of volunteer time in 2018-2019 and 1907 h in the 2019-2020 period. The Committee's implication spanned governance, expertise, and knowledge transfer in research. Participation in these activities increased annually at local, provincial, national and international levels. The Patient-Partner Committee collaborated with various local (n = 7), provincial (n = 6) and national (n = 4) partners. Member satisfaction with the Committee's mandate and format was 100%. CONCLUSIONS: The CRCHUS co-constructed a Patient-Partner Strategic Committee which resulted in meaningful bilateral, trusting and fruitful collaborations between patients, researchers and partners. The "bottom-up" approach - envisioned and implemented by the Committee, where the expertise and the needs of patients complemented those of researchers, foundations, networks and decision-makers - is key to the success of a cultural shift. The CRCHUS Committee created a hub to develop the relevant intrinsic potential aimed at changing the socio-cultural environment of science.
RESUMEN
OBJECTIVE: The aim of this study was to assess the involvement of lipoxygenase (LOX) metabolic pathways in uterine tissues from pregnant women as well as the combined inhibition of LOX and cyclooxygenase (COX) on contractile activity. STUDY DESIGN: Uterine biopsies were performed from consenting women undergoing elective caesarean sections at term (n = 24). Western blot analysis and isometric tension measurements were performed in vitro on fresh human myometrial strips. Concentration-response curves to arachidonic acid (AA) 861 and baicalein (5- and 12-LOX inhibitors, respectively) were performed. The combined effects of baicalein and indomethacin were also assessed. Contractile activities were quantified by calculating both amplitude and the area under the curve over 20 minute periods. RESULTS: 5- and 12-LOX were present in all tested tissues. Addition of AA861 or baicalein resulted in tocolytic effects (P < .05). Finally, the combined inhibition of both COX and 12-LOX pathways resulted in additive tocolytic effects. CONCLUSION: 5- and 12-LOX pathways modulate human myometrium contractility.
Asunto(s)
Inhibidores de la Ciclooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/farmacología , Lipooxigenasa/metabolismo , Miometrio/metabolismo , Contracción Uterina/efectos de los fármacos , Adulto , Benzoquinonas/farmacología , Biopsia , Western Blotting , Femenino , Flavanonas/farmacología , Humanos , Indometacina/farmacología , Isoenzimas , Miometrio/patología , Embarazo , Prostaglandina-Endoperóxido Sintasas/metabolismoRESUMEN
OBJECTIVE: The purpose of this study was to assess the effects of exogenous eicosanoids on spontaneous uterine contractile activity. STUDY DESIGN: Eight uterine biopsies were performed from women who were undergoing elective cesarean delivery. Tension measurements were performed in vitro on myometrial strips. Contractile activities were quantified by the calculation of the area under the curve. The effects of eicosanoids and specific enzyme inhibitors were assessed. Fractions from various uterine tissues were analyzed by Western blot. RESULTS: Data demonstrate the presence, in some tested tissues, of cytochrome P-450 epoxygenase and soluble epoxide hydrolase, which respectively produce and degrade epoxyeicosatrienoic acid regioisomers. Inhibition of soluble epoxide hydrolase with 12-(3-adamantan-1-yl-ureido)-dodecanoic acid or omega-hydroxylase with N-methylsulfonyl-12,12-dibromododec-11-enamide resulted in a tocolytic effect; N-methylsulfonyl-6-[2-propargyloxyphenyl] hexanamide, which is an epoxygenase inhibitor, had no effect. Exogenous epoxyeicosatrienoic acids displayed significant tocolytic effects on spontaneous contractile activities. CONCLUSION: Epoxy- and hydroxyeicosanoids represent new bioactive, arachidonic acid by-products with in vitro tocolytic activities. These findings suggest that cytochrome P-450 isozymes may represent relevant pharmacologic targets under physiopathologic conditions.
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Eicosanoides/farmacología , Tocolíticos/farmacología , Contracción Uterina/efectos de los fármacos , Adolescente , Adulto , Área Bajo la Curva , Western Blotting , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Técnicas In Vitro , Embarazo , Resistencia a la Tracción , Adulto JovenRESUMEN
Oxidative stress has been shown to induce ubiquitynation of RNA polymerase II, but direct bearing of that phenomenon on global transcription still remains elusive. In this report, we show that high levels of cellular oxidative stress globally inhibit gene transcription, and that this decrease in transcription is only partly attributable to reduced binding of RNA polymerase II to a model gene promoter. Importantly, we show that this decrease in transcription correlates with a significant decrease in histone H3 and H4 acetylation levels both throughout a model gene, and also globally in the nucleus of cells. Our results suggest that high levels of oxidative stress can inhibit transcription by a mechanism, at least in part, that impedes global histone acetylation levels.
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Histonas/metabolismo , Estrés Oxidativo , Transcripción Genética , Acetilación , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno/toxicidad , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismoRESUMEN
OBJECTIVE: To develop a new strategy of predicting spontaneous preterm birth (sPTB) by combination of transvaginal ultrasound (TVUS) assessment and inflammatory proteins detection in vaginal secretions. METHODS: Prospective study of 87 women referred for cervical length assessment with a standardized TVUS combined to vaginal secretions sampling. Samples were analyzed for presence of 10 cytokines. Main outcome was sPTB (<37 weeks of gestation). Associations were assessed with the chi-square, Fisher's exact test (p < 0.05) and Wald's logistic regression. RESULTS: sPTB occurred in 25.3% of women at a median gestational age of 35.6 weeks of gestation. Short cervix (<25 mm) (n = 24) was associated with sPTB (p < 0.01) as interleukine (IL)-1ß, IL-8 and IL-10 in vaginal secretions (p < 0.05). In multivariate analysis, short cervix and IL-8 in vaginal secretions were independently associated with sPTB (OR 3.58 (95%CI 1.02; 12.61) and 14.55 (95%CI 1.64; 128.83), respectively) as their combination (OR 4.33 (95%CI 1.25; 14.95)). By categorizing cervical length by presence of IL-8, sPTB occurred in 55.6% of women with a short inflamed cervix. CONCLUSION: COLIBRI study used a novel, single-step method of vaginal secretions sampling during TVUS and demonstrated that combination of short cervix and IL-8 in vaginal secretions is a promising sPTB predictive test.
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Medición de Longitud Cervical , Cuello del Útero/patología , Citocinas/metabolismo , Nacimiento Prematuro/diagnóstico , Vagina/metabolismo , Adulto , Biomarcadores/metabolismo , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/metabolismo , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Interleucina-8/metabolismo , Modelos Logísticos , Embarazo , Nacimiento Prematuro/metabolismo , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: The aim of this study was to validate the results of an immunochromatographic bedside test to detect IL6 and IL8 in vaginal secretions after rupture of membranes (ROM) with results obtained by ELISA tests. METHODS: A prospective cohort of 60 women with ROM or preterm ROM (PROM) was recruited. An immunochromatographic bedside test was performed with vaginal secretions samplings at admission, every 48 hrs until labor and during labor. Remaining samples were frozen for ELISA analysis. The results of bedside tests were compared to those from ELISA analysis for 114 samples. RESULTS: With all samples combined, the positive predictive values were 50% for IL6 and 86.8% for IL8 and the negative predictive values were 97.4% for IL6 and 53.3% for IL8. Kappa coefficients were 0.54 for IL6 and 0.41 for IL8. CONCLUSION: Our findings show that a bedside test can detect the absence of IL6 in vaginal secretions. This result suggests that bedside test could be used for expectant management after premature PROM to inform the attending physician of the absence of inflammation in vaginal secretions.
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Corioamnionitis/diagnóstico , Cromatografía de Afinidad/métodos , Rotura Prematura de Membranas Fetales/diagnóstico , Interleucina-6/análisis , Interleucina-8/análisis , Adulto , Corioamnionitis/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Rotura Prematura de Membranas Fetales/etiología , Rotura Prematura de Membranas Fetales/metabolismo , Humanos , Inflamación/diagnóstico , Inflamación/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Valor Predictivo de las Pruebas , Embarazo , Sensibilidad y Especificidad , Vagina/química , Vagina/metabolismo , Adulto JovenRESUMEN
OBJECTIVE: To determine the impact of the duration of fetal exposure to inflammation on the neurological outcome of pups. METHOD: Time-pregnant Sprague-Dawley rats (n = 32) received intraperitoneal injection of lipopolysaccharides (LPS; 500 µg/kg), or an equivalent volume of vehicle 3, 6, 12 and 24 h before C-section. Maternal serum and amniotic fluid were tested for cytokines. Motor activity of resuscitated pups (n = 58) was analyzed using the open-field test (20 d). Brains were collected for histopathological examination. RESULTS: Perinatal mortality increased with the duration of fetal exposure to LPS. All parameters tested with the open-field test were lower in the LPS 12 h exposure group compared to the control group (p < 0.05). Tissue inhibitor of metalloproteinase 1 (TIMP-1) was statistically increased in maternal blood after 3, 6 and 12 h of LPS injection (p < 0.05 versus control). CONCLUSION: A threshold of duration of exposure to inflammation is demonstrated, before which delivery should be performed in order to prevent brain damage.