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1.
Integr Comp Biol ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38599626

RESUMEN

How animal embryos determine their early cell fates is an important question in developmental biology. In various model animals asymmetrically localized maternal transcripts play important roles in axial patterning and cell fate specification. Cephalochordates (amphioxus), which have three living genera (Asymmetron, Epigonichthys, Branchiostoma), are an early branching chordate lineage and thus occupy a key phylogenetic position for understanding the evolution of chordate developmental mechanisms. It has been shown that in the zygote of Brachiostoma amphioxus, which possess bilateral gonads flanking both sides of their trunk region, maternal transcripts of germline determinants form a compact granule. During early embryogenesis this granule is inherited by a single blastomere that subsequently gives rise to a cluster of cells displaying typical characteristics of primordial germ cells (PGC). These PGCs then come to lie in the tailbud region and proliferate during posterior elongation of the larva to join in the gonad anlagen at the ventral tip of the developing myomeres in amphioxus larvae. However, in Asymmetron and Epigonichthys amphioxus, whose gonads are present only on the right side of their body, nothing is known about their PGC development or the cellular/morphogenetic processes resulting in the asymmetric distribution of gonads. Using conserved germline determinants as markers, we show that similarly to Brachiostoma amphioxus, Asymmetron also employ a preformation mechanism to specify their PGCs, suggesting that this mechanism represents an ancient trait dating back to the common ancestor of Cephalochordates. Surprisingly, we found that Asymmetron PGCs are initially deposited on both sides of the body during early larval development; however, the left side PGCs cease to exist in young juveniles, suggesting that PGCs are eliminated from the left body side during larval development or following metamorphosis. This is reminiscent of the PGC development in the sea urchin embryo, and we discuss the implications of this observation for the evolution of developmental mechanisms.

2.
Front Endocrinol (Lausanne) ; 12: 730059, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34616363

RESUMEN

Background: In recent years frozen-thawed embryo transfer (FET) has played an increasingly important role in ART, but there is limited consensus on the most effective method of endometrial preparation (EP) for FET. Inspired by significantly higher implantation rate and clinical pregnancy rate of the depot GnRH-a protocol, we proposed a novel EP protocol named down-regulation ovulation-induction (DROI) aimed to improve pregnancy outcomes of FET. Methods: This was a single-center, randomized controlled pilot trial. A total of 307 patients with freeze-all strategy scheduled for first FET were enrolled in the study. A total 261 embryos were transferred in DROI-FET group including 156 patients and 266 embryos were transferred in mNC-FET group including 151 patients. Reproductive outcomes were compared between the two groups. Results: The basic characteristics of patients, and the average number, quality and stage of embryos transferred were comparable between the two groups. Our primary outcome, implantation rate(IR) in DROI-FET group, was significantly higher than that of the mNC-FET group (54.41% versus 35.71%, P<0.01). The clinical pregnancy rate (CPR) and ongoing pregnancy rate (OPR) in DROI-FET group was also higher than that in mNC-FET group (69.87% versus 50.33%, P<0.01; 64.10% versus 42.38%, P<0.01). Conclusions: Compared to existing endometrial preparation methods, the DROI protocol might be the more efficient and promising protocol.


Asunto(s)
Criopreservación/métodos , Implantación del Embrión , Transferencia de Embrión/métodos , Endometrio/fisiología , Inducción de la Ovulación/métodos , Índice de Embarazo , Adulto , Endometrio/efectos de los fármacos , Femenino , Estudios de Seguimiento , Hormona Liberadora de Gonadotropina/administración & dosificación , Humanos , Masculino , Embarazo , Resultado del Embarazo , Estudios Prospectivos
3.
Am J Chin Med ; 47(5): 1113-1131, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31352786

RESUMEN

Pulmonary fibrosis (PF) is characterized by myofibroblast activation, which can be triggered by oxidative stress. In this study, we investigated the antifibrotic effect of the ethyl acetate extract of Salvia miltiorrhiza (EASM) on PF and examined the underlying molecular mechanism. EASM suppressed myofibroblast activation with reduced extracellular matrix deposition in the lungs of mice subjected to bleomycin (BLM) challenge, demonstrating the inhibitory effects on PF. EASM positively alleviated oxidative stress by upregulating nuclear factor-erythroid 2-related factor 2 (Nrf2) and concomitantly downregulating NADPH oxidase 4 (Nox4) in the lungs of BLM-treated mice. This effect was also observed in an in vitro model of transforming growth factor beta 1 (TGF-ß1)-stimulated fibroblast activation. EASM reduced reactive oxygen species (ROS) generation in fibroblasts by stabilizing Nrf2 protein with promoting kelch-like ECH-associated protein 1 (Keap1) degradation. Nrf2 knockdown in the lungs of BLM-treated mice diminished the inhibitory effects of EASM on fibrosis, providing evidence in vivo to address the unique role of Nrf2. Additionally, EASM inhibited TGF-ß1/Smad3 signaling by downregulating protein kinase C delta (PKC-δ) and Smad3 phosphorylation (p-Smad3), which led to suppression of the TGF-ß1-induced fibrogenic response. These results indicate that EASM exhibits potent antifibrotic activity in vitro and in vivo, which might be associated with activation of Nrf2 pathway and inhibition of TGF-ß1/Smad3 pathway. Our findings support that EASM may act as an effective antifibrotic remedy for PF.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , NADPH Oxidasa 4/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Salvia miltiorrhiza/química , Animales , Femenino , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , NADPH Oxidasa 4/genética , Factor 2 Relacionado con NF-E2/genética , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
4.
Antioxid Redox Signal ; 30(15): 1831-1848, 2019 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-30105924

RESUMEN

AIMS: Pulmonary fibrosis (PF) is characterized by myofibroblast activation through oxidative stress. However, the precise regulation of myofibroblast transdifferentiation remains largely uncharacterized. RESULTS: In this study, we found that tanshinone IIA (Tan-IIA), an active component in the root of Salvia miltiorrhiza Bunge, can suppress reactive oxygen species (ROS)-mediated activation of myofibroblast and reduce extracellular matrix deposition in bleomycin (BLM)-challenged mice through the regulation of nuclear factor-erythroid 2-related factor 2 (Nrf2). Additionally, Tan-IIA restored redox homeostasis by upregulating Nrf2 with NADPH oxidase 4 suppression and effectively prevented myofibroblast activation by blocking ROS-mediated protein kinase C delta (PKCδ)/Smad3 signaling. Nrf2 knockdown in the fibroblasts and the lungs of BLM-treated mice reduced the inhibitory effects of Tan-IIA, indicating the essential role of Nrf2 in the Tan-IIA activity. Tan-IIA impaired the binding of kelch-like ECH-associated protein 1 (Keap1) to Nrf2 by promoting the degradation of Keap1 and thereby increasing Nrf2 induction by protecting Nrf2 stability against ubiquitination and proteasomal degradation. Importantly, we also found that the glutamate anaplerotic pathway was involved in energy generation and biosynthesis in activated myofibroblasts and their proliferation. Tan-IIA shunted glutaminolysis into glutathione (GSH) production by activating Nrf2, resulting in the reduction of glutamate availability for tricarboxylic acid cycle. Ultimately, myofibroblast activation was prevented by impairing cell proliferation. Innovation and Conclusion: In addition to the regulation of redox homeostasis, our work showed that Tan-IIA activated Nrf2/GSH signaling pathway to limit glutaminolysis in myofibroblast proliferation, which provided further insight into the critical function of Nrf2 in PF.


Asunto(s)
Abietanos/farmacología , Glutamina/metabolismo , Homeostasis , Factor 2 Relacionado con NF-E2/agonistas , Oxidación-Reducción , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/metabolismo , Animales , Transdiferenciación Celular , Femenino , Fibroblastos/metabolismo , Expresión Génica , Glutatión/metabolismo , Humanos , Inmunohistoquímica , Ratones , Modelos Biológicos , Miofibroblastos/metabolismo , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Factor 2 Relacionado con NF-E2/química , Factor 2 Relacionado con NF-E2/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/patología , Especies Reactivas de Oxígeno/metabolismo
5.
Eur J Med Chem ; 151: 849-860, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29684895

RESUMEN

Xanthine oxidase, which catalyzes the oxidative reaction of hypoxanthine and xanthine into uric acid, is a key enzyme to the pathogenesis of hyperuricemia and gout. In this study, for the purpose of discovering novel xanthine oxidase (XO) inhibitors, a series of 2-arylbenzo[b]furan derivatives (3a-3d, 4a-4o and 6a-6d) were designed and synthesized. All these compounds were evaluated their xanthine oxidase inhibitory and antioxidant activities by using in vitro enzymatic assay and cellular model. The results showed that a majority of the designed compounds exhibited potent xanthine oxidase inhibitory effects and antioxidant activities, and compound 4a emerged as the most potent xanthine oxidase inhibitor (IC50 = 4.45 µM). Steady-state kinetic measurements of the inhibitor 4a with the bovine milk xanthine oxidase indicated a mixed type inhibition with 3.52 µM Ki and 13.14 µM Kis, respectively. The structure-activity relationship analyses have also been presented. Compound 4a exhibited the potent hypouricemic effect in the potassium oxonate-induced hyperuricemic mice model. A molecular docking study of compound 4a was performed to gain an insight into its binding mode with xanthine oxidase. These results highlight the identification of a new class of xanthine oxidase inhibitors that have potential to be more efficacious in treatment of gout.


Asunto(s)
Benzofuranos/química , Benzofuranos/farmacología , Diseño de Fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Animales , Antioxidantes/química , Antioxidantes/farmacología , Bovinos , Furanos , Masculino , Ratones , Ratones Endogámicos ICR , Simulación del Acoplamiento Molecular , Células RAW 264.7 , Relación Estructura-Actividad , Xantina Oxidasa/metabolismo
6.
Clin Lab ; 63(7): 1153-1162, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28792689

RESUMEN

BACKGROUND: Tau protein is s specific protein expressed by neurons in the central nervous system. Elevated serum Tau protein is associated with many diseases of the central nervous system. The serum Tau protein level in neonates with hypoxic ischemic encephalopathy (HIE) is still poorly understood. METHODS: Forty-one human neonates with HIE and thirty-five healthy neonates (control group) within 24 hours after birth were studied. Tau protein in serum was detected by enzyme-linked immunosorbent assay. Neurological outcome was assessed at 9 months of age according to the Gesell developmental scale. RESULTS: Tau protein in serum was significantly higher in the HIE group than in the control group (p < 0.01), in neonates with severe HIE than neonates with moderate HIE (p < 0.01), and in infants with neurodevelopmental retardation compared with those with normal neurodevelopment (p < 0.01). The result of this study showed an obvious negative correlation between the serum Tau protein level and development quotients of neonates with HIE (rs = -0.6172, p < 0.01). Receiver operator characteristic curve analysis showed that Tau protein (cutoff value 933.04 pg/mL) was a predictor of neurodevelopmental retardation outcome (AUC value = 0.860 (95% CI: 0.736 - 0.983, p < 0.01), sensitivity 100%, specificity 70.8%). CONCLUSIONS: Serum Tau protein level within 24 hours after birth can be used as a marker for the early diagnosis of neonatal HIE and predicting neurodevelopmental outcomes.


Asunto(s)
Hipoxia-Isquemia Encefálica/sangre , Proteínas tau/sangre , Biomarcadores/sangre , Proteínas Sanguíneas , Humanos , Recién Nacido , Sensibilidad y Especificidad
7.
Chin Med J (Engl) ; 128(7): 896-901, 2015 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-25836609

RESUMEN

BACKGROUND: Pulmonary hypertension (PH) frequently complicates the course of idiopathic pulmonary fibrosis (IPF) patients and is associated with significantly worse outcomes. The aim of the present study was to investigate the incidence of PH in IPF patients and evaluate the correlation between clinical parameters and systolic pulmonary artery pressure (sPAP). METHODS: Hospitalized patients with IPF, who were evaluated for sPAP by Doppler echocardiography from January 2004 to December 2011, were enrolled in our study. Patients were defined as PH by an estimated sPAP > 50 mmHg and graded as PH likely, PH possible and PH unlikely, based on the 2009 European Society of Cardiology/European Respiratory Society PH Guidelines. The correlations between clinical parameters and sPAP were analyzed by multiple linear regression. RESULTS: Totally, 119 IPF patients were enrolled in our study and 28 (23.5%), 20 (16.8%) and 71 (59.7%) patients were PH likely, PH possible and PH unlikely, respectively. Borg dyspnea score was positively correlated with sPAP, r = 0.467, P < 0.001. Oxygen saturation was negatively correlated with sPAP, r = -0.416, P < 0.001. Diffusing capacity of the lung for carbon monoxide percentage predicted was negatively correlated with sPAP, r = -0.424, P = 0.003. N-terminal fragment of pro-brain natriuretic peptide and pulmonary artery width was positively correlated with sPAP, r = 0.452, P = 0.011 and r = 0.513, P < 0.001, respectively. CONCLUSIONS: The incidence of PH in IPF patients was 23.5% in a single center of China. PH may worsen the dyspnea, right heart dysfunction and decrease the life quality of the patients with IPF.


Asunto(s)
Hipertensión Pulmonar/epidemiología , Hipertensión Pulmonar/fisiopatología , Fibrosis Pulmonar Idiopática/epidemiología , Fibrosis Pulmonar Idiopática/fisiopatología , Anciano , Ecocardiografía Doppler , Femenino , Humanos , Hipertensión Pulmonar/sangre , Fibrosis Pulmonar Idiopática/sangre , Incidencia , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Arteria Pulmonar/fisiopatología , Fumar
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