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During in vitro maturation, excess levels of reactive oxygen species (ROS) are a major cause of developmental defects in embryos. Betulinic acid (BA) is a naturally produced antioxidant in white birch bark. Recent studies have shown that BA exhibits antioxidant properties in various cells through the activation of antioxidant genes. Therefore, we investigated the effect of BA treatment on porcine oocytes and its underlying mechanism during oocyte maturation. Treatment with 0.1 µM BA significantly increased the proportion of MII oocytes compared with controls, and BA-treated oocytes had significantly higher development rates, trophectoderm cell numbers, and cell survival rates than controls. These results demonstrate that BA treatment improved the developmental competence of oocytes. Following BA treatment, oocytes exhibited reduced ROS levels and elevated glutathione (GSH) levels, accompanied by the enhanced expression of antioxidant genes, compared with control oocytes. To evaluate the antioxidant effects of BA, oocytes were exposed to H2O2, a potent ROS activator. Impaired nuclear maturation, ROS levels, and GSH levels induced in oocytes by H2O2 exposure was restored by BA treatment. As these antioxidant genes are regulated by the Nrf2/Keap1 signaling pathway, which is involved in antioxidant responses, we applied the Nrf2 inhibitor brusatol to investigate the effects of BA on this pathway. The negative effects of brusatol on meiotic maturation and oocyte quality, including levels of ROS, GSH, and antioxidant-related gene expression, were mitigated by BA treatment. Our results suggested that BA plays an effective role as an antioxidant in porcine oocyte maturation through adjusting the Nrf2/Keap1 signaling pathway. This finding provides valuable insights into the mechanisms governing oocyte maturation and embryonic development.
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Antioxidantes , Ácido Betulínico , Glutatión , Proteína 1 Asociada A ECH Tipo Kelch , Factor 2 Relacionado con NF-E2 , Oocitos , Triterpenos Pentacíclicos , Especies Reactivas de Oxígeno , Transducción de Señal , Triterpenos , Animales , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Triterpenos/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Transducción de Señal/efectos de los fármacos , Antioxidantes/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Especies Reactivas de Oxígeno/metabolismo , Glutatión/metabolismo , Porcinos , Peróxido de Hidrógeno , FemeninoRESUMEN
Frequent recurrence and metastasis caused by cancer stem cells (CSCs) are major challenges in lung cancer treatment. Therefore, identifying and characterizing specific CSC targets are crucial for the success of prospective targeted therapies. In this study, it is found that upregulated TOR Signaling Pathway Regulator-Like (TIPRL) in lung CSCs causes sustained activation of the calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) signaling pathway by binding to CaMKK2, thereby maintaining stemness and survival. CaMKK2-mediated activation of CaM kinase 4 (CaMK4) leads to phosphorylation of cAMP response element-binding protein (CREB) at Ser129 and Ser133, which is necessary for its maximum activation and the downstream constitutive expression of its target genes (Bcl2 and HMG20A). TIPRL depletion sensitizes lung CSCs to afatinib-induced cell death and reduces distal metastasis of lung cancer in vivo. It is determined that CREB activates the transcription of TIPRL in lung CSCs. The positive feedback loop consisting of CREB and TIPRL induces the sustained activation of the CaMKK2-CaMK4-CREB axis as a driving force and upregulates the expression of stemness- and survival-related genes, promoting tumorigenesis in patients with lung cancer. Thus, TIPRL and the CaMKK2 signaling axis may be promising targets for overcoming drug resistance and reducing metastasis in lung cancer.
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Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Neoplasias Pulmonares , Células Madre Neoplásicas , Transducción de Señal , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Humanos , Células Madre Neoplásicas/metabolismo , Ratones , Animales , Transducción de Señal/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Proteína Quinasa Tipo 4 Dependiente de Calcio Calmodulina/metabolismo , Proteína Quinasa Tipo 4 Dependiente de Calcio Calmodulina/genética , Línea Celular Tumoral , Retroalimentación Fisiológica , Modelos Animales de EnfermedadRESUMEN
Human blood vessel organoids (hBVOs) offer a promising platform for investigating vascular diseases and identifying therapeutic targets. In this study, we focused on in vitro modeling and therapeutic target finding of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the most common form of hereditary stroke disorder caused by mutations in the NOTCH3 gene. Despite the identification of these mutations, the underlying pathological mechanism is elusive, and effective therapeutic approaches are lacking. CADASIL primarily affects the blood vessels in the brain, leading to ischemic strokes, migraines, and dementia. By employing CRISPR/Cas9 base-editing technology, we generated human induced pluripotent stem cells (hiPSCs) carrying Notch3 mutations. These mutant hiPSCs were differentiated into hBVOs. The NOTCH3 mutated hBVOs exhibited CADASIL-like pathology, characterized by a reduced vessel diameter and degeneration of mural cells. Furthermore, we observed an accumulation of Notch3 extracellular domain (Notch3ECD), increased apoptosis, and cytoskeletal alterations in the NOTCH3 mutant hBVOs. Notably, treatment with ROCK inhibitors partially restored the disconnection between endothelial cells and mural cells in the mutant hBVOs. These findings shed light on the pathogenesis of CADASIL and highlight the potential of hBVOs for studying and developing therapeutic interventions for this debilitating human vascular disorder.
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Vasos Sanguíneos , CADASIL , Edición Génica , Células Madre Pluripotentes Inducidas , Organoides , Receptor Notch3 , Receptor Notch3/genética , Receptor Notch3/metabolismo , CADASIL/patología , CADASIL/genética , CADASIL/metabolismo , Humanos , Organoides/patología , Organoides/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Vasos Sanguíneos/patología , Polimorfismo de Nucleótido Simple/genética , Mutación/genética , Diferenciación Celular , Apoptosis/genéticaRESUMEN
NIMA-related kinase 2 (NEK2) is a serine/threonine protein kinase that regulates mitosis and plays pivotal roles in cell cycle regulation and DNA damage repair. However, its function in porcine embryonic development is unknown. In this study, we used an NEK2-specific inhibitor, JH295 (JH), to investigate the role of NEK2 in embryonic development and the underlying regulatory mechanisms. Inhibition of NEK2 after parthenogenesis activation or in vitro fertilization significantly reduced the rates of cleavage and blastocyst formation, the numbers of trophectoderm and total cells and the cellular survival rate compared with the control condition. NEK2 inhibition delayed cell cycle progression at all stages from interphase to cytokinesis during the first mitotic division; it caused abnormal nuclear morphology in two- and four-cell stage embryos. Additionally, NEK2 inhibition significantly increased DNA damage and apoptosis, and it altered the expression levels of DNA damage repair- and apoptosis-related genes. Intriguingly, NEK2 inhibition downregulated the expression of ß-catenin and its downstream target genes. To validate the relationship between Wnt/ß-catenin signalling and NEK2 during porcine embryonic development, we cultured porcine embryos in JH-treated medium with or without CHIR99021, a Wnt activator. CHIR99021 co-treatment strongly restored the developmental parameters reduced by NEK2 inhibition to control levels. Our findings suggest that NEK2 plays an essential role in porcine embryonic development by regulating DNA damage repair and normal mitotic division via the Wnt/ß-catenin signalling pathway.
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Daño del ADN , Desarrollo Embrionario , Mitosis , Quinasas Relacionadas con NIMA , Vía de Señalización Wnt , Animales , Quinasas Relacionadas con NIMA/metabolismo , Quinasas Relacionadas con NIMA/antagonistas & inhibidores , Quinasas Relacionadas con NIMA/genética , Vía de Señalización Wnt/efectos de los fármacos , Porcinos , Mitosis/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , beta Catenina/metabolismo , Apoptosis/efectos de los fármacos , FemeninoRESUMEN
BACKGROUND: Oxidative stress, caused by an imbalance in the production and elimination of intracellular reactive oxygen species (ROS), has been recognized for its detrimental effects on mammalian embryonic development. Luteolin (Lut) has been documented for its protective effects against oxidative stress in various studies. However, its specific role in embryonic development remains unexplored. This study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying mechanism. RESULTS: After undergoing parthenogenetic activation (PA) or in vitro fertilization, embryos supplemented with 0.5 µmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates, with an increase in total cell numbers and a decrease in the apoptosis rate compared to the control. Measurements on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the control. Moreover, Lut supplementation significantly augmented mitochondrial content and membrane potential. Intriguingly, activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut, leading to the upregulation of antioxidant-related gene transcription levels. To further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development, we cultured PA embryos in a medium supplemented with brusatol, with or without the inclusion of Lut. The positive effects of Lut on developmental competence were negated by brusatol treatment. CONCLUSIONS: Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence, and offers insight into the mechanisms regulating early embryonic development.
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Luteolin (Lut), a polyphenolic compound that belongs to the flavone subclass of flavonoids, possesses anti-inflammatory, cytoprotective, and antioxidant activities. However, little is known regarding its role in mammalian oocyte maturation. This study examined the effect of Lut supplementation during in vitro maturation (IVM) on oocyte maturation and subsequent developmental competence after somatic cell nuclear transfer (SCNT) in pigs. Lut supplementation significantly increased the proportions of complete cumulus cell expansion and metaphase II (MII) oocytes, compared with control oocytes. After parthenogenetic activation or SCNT, the developmental competence of Lut-supplemented MII oocytes was significantly enhanced, as indicated by higher rates of cleavage, blastocyst formation, expanded or hatching blastocysts, and cell survival, as well as increased cell numbers. Lut-supplemented MII oocytes exhibited significantly lower levels of reactive oxygen species and higher levels of glutathione than control MII oocytes. Lut supplementation also activated lipid metabolism, assessed according to the levels of lipid droplets, fatty acids, and ATP. The active mitochondria content and mitochondrial membrane potential were significantly increased, whereas cytochrome c and cleaved caspase-3 levels were significantly decreased, by Lut supplementation. These results suggest that Lut supplementation during IVM improves porcine oocyte maturation through the reduction of oxidative stress and mitochondria-mediated apoptosis.
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Técnicas de Maduración In Vitro de los Oocitos , Luteolina , Porcinos , Animales , Luteolina/farmacología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oogénesis , Oocitos , Suplementos Dietéticos , MamíferosRESUMEN
Cadmium (Cd) is toxic metal that can induce various diseases, such as cardiovascular, nervous, and reproductive systems. This study investigated the effect of Cd exposure on porcine oocyte maturation and the underlying mechanism. Porcine cumulus-oocyte complexes were exposed various Cd concentration and tauroursodeoxycholic acid (TUDCA), an inhibitor of endoplasmic reticulum (ER) stress during in vitro maturation (IVM). After IVM, we evaluated meiotic maturation, ER stress, and oocyte quality by Cd exposure. Cd exposure inhibited cumulus cell expansion and meiotic maturation, increased oocyte degeneration, and induced ER stress. The levels of spliced XBP1 and ER stress-associated transcripts, markers of ER stress, were elevated in Cd-treated cumulus-oocyte complexes and denuded oocytes during IVM. Moreover, Cd-induced ER stress impaired oocyte quality by disrupting mitochondrial function and elevating intracellular reactive oxygen species levels while decreasing ER function. Interestingly, TUDCA supplementation significantly decreased the expression of ER stress-related genes and increased the quantity of ER compared with the Cd treatment. Additionally, TUDCA was also able to rescue excessive levels of ROS and restore normal mitochondrial function. Moreover, the addition of TUDCA under Cd exposure greatly ameliorated Cd-mediated detrimental effects on meiotic maturation and oocyte quality, including cumulus cell expansion and MII rate. These findings suggest that Cd exposure during IVM impairs the meiotic maturation of oocytes by inducing of ER stress.
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Cadmio , Técnicas de Maduración In Vitro de los Oocitos , Animales , Porcinos , Cadmio/toxicidad , Cadmio/metabolismo , Oocitos , Estrés del Retículo EndoplásmicoRESUMEN
The sonic hedgehog (SHH) pathway is an important signaling pathway for mammalian ovarian folliculogenesis and oocyte maturation. A previous study demonstrated that low-quality porcine cumulus-oocyte complexes (COCs) have low developmental competence, with lower SHH signaling protein expression before and after in vitro maturation (IVM) than high-quality COCs. However, there is no reported evidence on the restorative effects of SHH protein supplementation during the IVM of low-quality porcine COCs. Therefore, this study investigated the effects of SHH protein supplementation on the IVM of low-quality porcine COCs, as assessed by brilliant cresyl blue (BCB) staining. To examine this, we designed four groups: (i) BCB- (low-quality), (ii) BCB- + SHH, (iii) BCB+ (high-quality), and (iv) BCB+ + SHH. While the supplementation of SHH protein with high-quality COCs had no effect, supplementation with low-quality COCs significantly improved cumulus cell expansion, metaphase II rate, and subsequent embryo development following parthenogenetic activation. Our results provide the first evidence that the low developmental competence of low-quality porcine COCs can be improved by supplementation with the SHH protein. These results indicate that an active SHH signaling pathway is required for the acquisition of developmental competence in porcine COCs.
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BACKGROUND: Melatonin is a multifunctional hormone synthesized in the pineal gland and peripheral reproductive tissues that regulates many biological processes. There is increasing evidence for a role of melatonin in oocyte maturation and embryonic development in various mammals. However, no study has reported evidence for the existence of melatonergic system, such as melatonin synthesis enzymes, melatonin membrane receptors, or melatonin binding sites in non-human primate cumulus-oocyte complexes (COCs). METHODS: Reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry were performed to detect transcripts and proteins of the rate-limiting enzyme in melatonin synthesis (arylalkylamine N-acetyltransferase, AANAT), melatonin membrane receptors (MT1 and MT2), and a melatonin binding site (NRH: quinone oxidoreductase 2, NQO2) in cynomolgus monkey COCs. RESULTS: RT-PCR analyses revealed the presence of AANAT, MT1, MT2, and NQO2 transcripts in granulosa cells, germinal vesicle (GV)- and metaphase II (MII)-stage cumulus cells, and oocytes. Immunocytochemistry revealed the presence of AANAT, MT1, MT2, and NQO2 proteins in GV- and MII-stage COCs. CONCLUSIONS: Our results provide the first evidence for the existence of the rate-limiting enzyme required for melatonin synthesis, melatonin membrane receptors, and a melatonin binding site in non-human primate COCs.
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Melatonina , Femenino , Animales , Macaca fascicularis/metabolismo , Melatonina/metabolismo , Oocitos , Receptores de Melatonina/metabolismo , Células del Cúmulo/metabolismo , Mamíferos/metabolismoRESUMEN
BACKGROUND: Anethole (AN) is an organic antioxidant compound with a benzene ring and is expected to have a positive impact on early embryogenesis in mammals. However, no study has examined the effect of AN on porcine embryonic development. Therefore, we investigated the effect of AN on the development of porcine embryos and the underlying mechanism. RESULTS: We cultured porcine in vitro-fertilized embryos in medium with AN (0, 0.3, 0.5, and 1 mg/mL) for 6 d. AN at 0.5 mg/mL significantly increased the blastocyst formation rate, trophectoderm cell number, and cellular survival rate compared to the control. AN-supplemented embryos exhibited significantly lower reactive oxygen species levels and higher glutathione levels than the control. Moreover, AN significantly improved the quantity of mitochondria and mitochondrial membrane potential, and increased the lipid droplet, fatty acid, and ATP levels. Interestingly, the levels of proteins and genes related to the sonic hedgehog (SHH) signaling pathway were significantly increased by AN. CONCLUSIONS: These results revealed that AN improved the developmental competence of porcine preimplantation embryos by activating SHH signaling against oxidative stress and could be used for large-scale production of high-quality porcine embryos.
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Arsenic (AS), an environmental contaminant, is a known human carcinogen that can cause cancer of the lung, liver, and skin. Furthermore, AS induces oxidative stress and mitochondrial impairments in mammalian cells. However, limited information is available on the effect of AS exposure on oocyte maturation of porcine, whose anatomy, physiology, and metabolism are similar to those of human. Therefore, we examined the effect of AS exposure on the in vitro maturation (IVM) of porcine oocytes and the possible underlying mechanisms. Cumulus-cell enclosed oocytes were cultured with or without AS for maturation, and then were used for analyses. This study indicated that AS under a concentration of 1 µM significantly increased the abnormal expansion of cumulus cells and the number of oocytes maintained in meiotic arrest. In addition, AS exposure significantly reduced subsequent development of embryos and increased the rate of apoptosis of blastocysts following parthenogenetic activation (PA) and in vitro fertilization (IVF). Moreover, AS exposure induced oxidative stress with increased reactive oxygen species (ROS), and decreased glutathione (GSH), leading to reduced mitochondrial membrane potential, mitochondrial quantity, DNA damage, excessive autophagy activity, and early apoptosis in porcine oocytes. Taken together, the results demonstrated that AS exposure exerts several negative effects, such as meiotic defects and embryo developmental arrest by causing mitochondrial dysfunction and apoptosis via inducing oxidative stress.
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Arsénico , Técnicas de Maduración In Vitro de los Oocitos , Animales , Apoptosis , Arsénico/metabolismo , Blastocisto , Carcinógenos/metabolismo , Desarrollo Embrionario , Femenino , Glutatión/metabolismo , Humanos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Mamíferos/metabolismo , Mitocondrias , Oocitos , Estrés Oxidativo , Embarazo , Especies Reactivas de Oxígeno/metabolismo , PorcinosRESUMEN
Universally acceptable donor cells have been developed to address the unmet need for immunotypically matched materials for regenerative medicine. Since forced expression of hypoimmunogenic genes represses the immune response, we established universal pluripotent stem cells (PSCs) by replacing endogenous ß2-microglobulin (ß2m) with ß2m directly conjugated to human leukocyte antigen (HLA)-G, thereby simultaneously suppressing HLA-I expression and the natural killer (NK) cell-mediated immune response. These modified human PSCs retained their pluripotency and differentiation capacity; however, surface presentation of HLA-G was absent from subsequently differentiated cells, particularly cells of neural lineages, due to the downregulation of antigen processing and presentation machinery (APM) genes. Induction of APM genes by overexpression of NLR-family CARD domain-containing 5 (NLRC5) or activator subunit of nuclear factor kappa B (NF-κB) heterodimer (RelA) recovered the surface expression of HLA-G and the hypoimmunogenicity of neural cells. Our findings enhance the utility of hypoimmunogenic cells as universal donors and will contribute to the development of off-the-shelf stem-cell therapeutics.
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Glycosylphosphatidylinositol-anchored sperm hyaluronidases (HYAL) assist sperm penetration through the cumulus-oocyte complex (COC), but their role in mammalian fertilization remains unclear. Previously, we demonstrated that sperm from HYAL 5 and 7 double-knockout (dKO) mice produced significantly less offspring than sperm from wild-type mice due to defective COC dispersal. However, the HYAL6 gene remained active in the sperm from the dKO mice, indicating that they were not entirely infertile. This study explored the role of HYAL6 in fertilization by analyzing HYAL6-mutant mice. In this mouse model, HYAL5 and HYAL7 were present in the HYAL6-knockout sperm, and they could disperse hyaluronic acid. We found that HYAL6 was present on the surface of sperm. However, male mice lacking the HYAL6 gene had normal fertility, testicular integrity, and sperm characteristics. Furthermore, in vitro fertilization assays demonstrated that HYAL6-deficient epididymal sperm functioned normally. Therefore, HYAL6 is dispensable for fertilization.
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Moléculas de Adhesión Celular , Hialuronoglucosaminidasa , Animales , Moléculas de Adhesión Celular/genética , Fertilidad/genética , Hialuronoglucosaminidasa/genética , Masculino , Mamíferos , Ratones , Oocitos , Interacciones Espermatozoide-Óvulo/genéticaRESUMEN
Prime editing can induce a desired base substitution, insertion, or deletion in a target gene using reverse transcriptase after nick formation by CRISPR nickase. In this study, we develop a technology that can be used to insert or replace external bases in the target DNA sequence by linking reverse transcriptase to the Francisella novicida Cas9, which is a CRISPR-Cas9 ortholog. Using FnCas9(H969A) nickase, the targeting limitation of existing Streptococcus pyogenes Cas9 nickase [SpCas9(H840A)]-based prime editing is dramatically extended, and accurate prime editing is induced specifically for the target genes in human cell lines.
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Sistemas CRISPR-Cas , Edición Génica , Desoxirribonucleasa I/metabolismo , Francisella , Humanos , ADN Polimerasa Dirigida por ARNRESUMEN
Glycosylphosphatidylinositol-anchored sperm hyaluronidases have long been believed to assist in sperm penetration through the cumulus-oocyte complex (COC); however, their role in mammalian fertilization remains unclear. Previously, we have shown that hyaluronidase 5 (Hyal5)/Hyal7 double-knockout (dKO) mice produce significantly fewer offspring than their wild-type (WT) counterparts because of defective COC dispersal. Male infertility is mainly caused by a low sperm count. It can be further exacerbated by the deficiency of sperm hyaluronidase, which disperses the cumulus cells of the outer layer of the COC. In the current study, we evaluated the effects of a low count of Hyal-deficient sperm and conditions of ovulated oocytes on the fertilization rate using a mouse model. Our results demonstrated that a low sperm count further decreases the in vitro fertilization (IVF) rate of Hyal-deficient dKO spermatozoa. In addition, the dKO spermatozoa resulted in a fertilization rate of 12.5% upon fertilizing COCs with a thick cumulus layer, whereas the IVF rate was comparable to that of WT spermatozoa when oocytes with a thin or no cumulus layer were fertilized. Finally, we proved that the IVF rate of dKO spermatozoa could be recovered by adding rat spermatozoa as a source of sperm hyal. Our results suggest that a deficiency of proteins involved in fertilization, such as sperm hyal, has a vital role in fertilization.
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Hialuronoglucosaminidasa , Oligospermia , Animales , Fertilización , Fertilización In Vitro , Humanos , Hialuronoglucosaminidasa/genética , Hialuronoglucosaminidasa/metabolismo , Masculino , Mamíferos/metabolismo , Oligospermia/metabolismo , Oocitos , Ratas , Semen/metabolismo , Interacciones Espermatozoide-Óvulo , Espermatozoides/metabolismoRESUMEN
BACKGROUND: Cryopreservation can expand the usefulness of spermatogonial stem cells (SSCs) in various fields. However, previous investigations that have attempted to modulate cryoinjury-induced mechanisms to increase cryoprotective efficiency have mainly focused on apoptosis and necrosis. OBJECTIVES: This study aimed to establish an effective molecular-based cryoprotectant for SSC cryopreservation via autophagy modulation. MATERIALS AND METHODS: To determine the efficacy of autophagy modulation, we assessed the recovery rate and relative proliferation rate and performed western blotting for the determination of autophagy flux, immunocytochemistry and real-time quantitative polymerase chain reaction (RT-qPCR) for SSC characterization, and spermatogonial transplantation for in vivo SSC functional activity. RESULTS: The results showed that a basal level of autophagy caused a higher relative proliferation rate (pifithrin-µ 0.01 µM, 184.2 ± 11.2%; 3-methyladenine 0.01 µM, 175.3 ± 10.3%; pifithrin-µ 0.01 µM + 3-methyladenine 0.01 µM, P3, 224.6 ± 22.3%) than the DMSO control (100 ± 6.2%). All treatment groups exhibited normal characteristics, suggesting that these modulators could be used as effective cryoprotectants without changing the properties of the undifferentiated germ cells. According to the results of the in vivo spermatogonial transplantation assay, the colonies per total number of cultured SSCs was significantly higher in the pifithrin-µ 0.01 µM (1596.7 ± 172.5 colonies), 3-methyladenine 0.01 µM (1522.1 ± 179.2 colonies), and P3 (1727.5 ± 196.5 colonies) treatment groups than in the DMSO control (842.8 ± 110.08 colonies), which was comparable to that of the fresh control (1882.1 ± 132.1 colonies). DISCUSSION: A basal level of autophagy is more essential for resilience in frozen SSCs after thawing, rather than the excessive activation or inhibition of autophagy. CONCLUSION: A basal level of autophagy plays a critical role in the pro-survival response of frozen SSCs after thawing; herein, a new approach by which SSC cryoprotective efficiency can be improved was identified.
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Células Madre Germinales Adultas/efectos de los fármacos , Autofagia/efectos de los fármacos , Criopreservación , Crioprotectores/farmacología , Espermatogonias/citología , Animales , Masculino , RatonesRESUMEN
Cancer stem cells (CSCs) initiate tumor formation and are known to be resistant to chemotherapy. A metabolic alteration in CSCs plays a critical role in stemness and survival. However, the association between mitochondrial energy metabolism and the redox system remains undefined in colon CSCs. In this study, we assessed the role of the Sulfiredoxin-Peroxiredoxin (Srx-Prx) redox system and mitochondrial oxidative phosphorylation (OXPHOS) in maintaining the stemness and survival of colon CSCs. Notably, Srx contributed to the stability of PrxI, PrxII, and PrxIII proteins in colon CSCs. Increased Srx expression promoted the stemness and survival of CSCs and was important for the maintenance of the mitochondrial OXPHOS system. Furthermore, Nrf2 and FoxM1 led to OXPHOS activation and upregulated expression of Srx-Prx redox system-related genes. Therefore, the Nrf2/FoxM1-induced Srx-Prx redox system is a potential therapeutic target for eliminating CSCs in colon cancer.
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Background: Titanium is commonly used in blood-exposed medical devices because it has superior blood compatibility. Mycophenolic acid inhibits the proliferation of vascular smooth muscle cells. This study examined the effect of a non-polymer TiO2 thin film-coated stent with mycophenolic acid in a porcine coronary overstretch restenosis model. Methods: Thirty coronary arteries in 15 pigs were randomized into three groups in which the coronary arteries were treated with a TiO2 film-coated stent with mycophenolic acid (NTM, n = 10), everolimus-eluting stent with biodegradable polymer (EES, n = 10), or TiO2 film-coated stent (NT, n = 10). A histopathologic analysis was performed 28 days after the stenting. Results: There were no significant intergroup differences in injury score, internal elastic lamina area, or inflammation score. Percent area stenosis was significantly smaller in the NTM and EES groups than in the NT group (36.1 ± 13.63% vs. 31.6 ± 7.74% vs. 45.5 ± 18.96%, respectively, p = 0.0003). Fibrin score was greater in the EES group than in the NTM and NT groups [2.0 (range, 2.0-2.0) vs. 1.0 (range, 1.0-1.75) vs. 1.0 (range, 1.0-1.0), respectively, p < 0.0001]. The in-stent occlusion rate measured by micro-computed tomography demonstrated similar percent area stenosis rates on histology analysis (36.1 ± 15.10% in NTM vs. 31.6 ± 8.89% in EES vs. 45.5 ± 17.26% in NT, p < 0.05). Conclusion: The NTM more effectively reduced neointima proliferation than the NT. Moreover, the inhibitory effect of NTM on smooth muscle cell proliferation was not inferior to that of the polymer-based EES with lower fibrin deposition in this porcine coronary restenosis model.
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BACKGROUND: Peroxiredoxins (Prxs) are antioxidant enzymes that protect cells from oxidative stress induced by several factors. They regulate several signaling pathways, such as metabolism, immune response, and intracellular reactive oxygen species (ROS) homeostasis. Epithelial-mesenchymal transition (EMT) is a transforming process that induces the loss of epithelial features of cancer cells and the gain of the mesenchymal phenotype. The EMT promotes metastasis and cancer cell progression mediated by several pathways, such as mitogen-activated protein kinases (MAPKs) and epigenetic regulators. METHODS: We used Prx6 overexpressed and downregulated HCT116 cells to study the mechanism between Prx6 and colon cancer. The expression of Prx6, GAPDH, Snail, Twist1, E-cadherin, Vimentin, N-cadherin, ERK, p-ERK, p38, p-p38, JNK, and p-JNK were detected by Western blotting. Additionally, an animal study for xenograft assay was conducted to explore the function of Prx6 on tumorigenesis. Cell proliferation and migration were determined by IncuCyte Cell Proliferation and colony formation assays. RESULTS: We confirmed that the expression of Prx6 and EMT signaling highly occurs in HCT116 compared with that in other colon cancer cell lines. Prx6 regulates the EMT signaling pathway by modulating EMT-related transcriptional repressors and mesenchymal genes in HCT116 colon cancer cells. Under the Prx6-overexpressed condition, HCT116 cells proliferation increased significantly. Moreover, the HCT116 cells proliferation decreased in the siPrx6-treated cells. Eleven days after HCT116 cell injection, Prx6 was overexpressed in the HCT116-injected mice, and the tumor volume increased significantly compared with that of the control mice. Furthermore, Prx6 regulates EMT signaling through p38 phosphorylation in colon cancer cells. CONCLUSION: We suggested that Prx6 regulates EMT signaling pathway through p38 phosphorylation modulation in HCT116 colon cancer cells.
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Developmental defects in somatic cell nuclear transfer (SCNT) embryos are principally attributable to incomplete epigenetic reprogramming. Small-molecule inhibitors such as histone methyltransferase inhibitors (HMTi) and histone deacetylase inhibitors (HDACi) have been used to improve reprogramming efficiency of SCNT embryos. However, their possible synergistic effect on epigenetic reprogramming has not been studied. In this study, we explored whether combined treatment with an HMTi (chaetocin) and an HDACi (trichostatin A; TSA) synergistically enhanced epigenetic reprogramming and the developmental competence of porcine SCNT embryos. Chaetocin, TSA, and the combination significantly increased the cleavage and blastocyst formation rate, hatching/hatched blastocyst rate, and cell numbers and survival rate compared to control embryos. In particular, the combined treatment improved the rate of development to blastocysts more so than chaetocin or TSA alone. TSA and combined chaetocin/TSA significantly reduced the H3K9me3 levels and increased the H3K9ac levels in SCNT embryos, although chaetocin alone significantly reduced only the H3K9me3 levels. Moreover, these inhibitors also decreased global DNA methylation in SCNT embryos. In addition, the expression of zygotic genome activation- and imprinting-related genes was increased by chaetocin or TSA, and more so by the combination, to levels similar to those of in vitro-fertilized embryos. These results suggest that combined chaetocin/TSA have synergistic effects on improving the developmental competences by regulating epigenetic reprogramming and correcting developmental potential-related gene expression in porcine SCNT embryos. Therefore, these strategies may contribute to the generation of transgenic pigs for biomedical research.