Stabilization of F-Actin Cytoskeleton by Paclitaxel Improves the Blastocyst Developmental Competence through P38 MAPK Activity in Porcine Embryos

IP3R1 dysregulation via mir-200c-3p/SSFA2 axis contributes to taxol resistance in head and neck cancer

Head and neck cancer (HNC) is the sixth most common malignancy worldwide. Although current modalities offer a wide variety of therapy choices, head and neck carcinoma has poor prognosis due to its diagnosis at later stages and development of resistance to current therapeutic tools. In the current study, we aimed at exploring the roles of miR-200c-3p during head and neck carcinogenesis and acquisition of taxol resistance. We analyzed miR-200c-3p levels in HNC clinical samples and cell lines using quantitative real-time polymerase chain reaction and evaluated the effects of differential miR-200c-3p expression on cancer-related cellular phenotypes using in-vitro tools. We identified and characterized a direct target of miR-200c-3p using in-silico tools, luciferase and various in-vitro assays. We investigated potential involvement of miR-200c-3p/SSFA2 axis in taxol resistance in-vitro. We found miR-200c-3p expression as significantly downregulated in both HNC tissues and cells compared to corresponding controls. Ectopic miR-200c-3p expression in HNC cells significantly inhibited cancer-related phenotypes such as viability, clonogenicity, migration, and invasion. We, then, identified SSFA2 as a direct target of miR-200c-3p and demonstrated that overexpression of SSFA2 induced malignant phenotypes in HNC cells. Furthermore, we found reduced miR-200c-3p expression in parallel with overexpression of SSFA2 in taxol resistant HNC cells compared to parental sensitive cells. Both involved in intracellular cytoskeleton remodeling, we found that SSFA2 works collaboratively with IP3R1 to modulate resistance to taxol in HNC cells. When considered collectively, our results showed that miR-200c-3p acts as a tumor suppressor microRNA and targets SSFA2/IP3R1 axis to sensitize HNC cells to taxol.

Deoxynivalenol leads to endoplasmic reticulum stress-mediated apoptosis via the IRE1/JNK/CHOP pathways in porcine embryos

The cytotoxic mycotoxin deoxynivalenol (DON) reportedly has adverse effects on oocyte maturation and embryonic development in pigs. Recently, the interplay between cell apoptosis and endoplasmic reticulum (ER) stress has garnered increasing attention in embryogenesis. However, the involvement of the inositol-requiring enzyme 1 (IRE1)/c-jun N-terminal kinase (JNK)/C/EBP homologous protein (CHOP) pathways of unfolded protein response (UPR) signaling in DON-induced apoptosis in porcine embryos remains unknown. In this study, we revealed that exposure to DON (0.25 μM) substantially decreased cell viability until the blastocyst stage in porcine embryos, concomitant with initiation of cell apoptosis through the IRE1/JNK/CHOP pathways in response to ER stress. Quantitative PCR confirmed that UPR signaling-related transcription factors were upregulated in DON-treated porcine blastocysts. Western blot analysis showed that IRE1/JNK/CHOP signaling was activated in DON-exposed porcine embryos, indicating that ER stress-associated apoptosis was instigated. The ER stress inhibitor tauroursodeoxycholic acid protected against DON-induced ER stress in porcine embryos, indicating that the toxic effects of DON on early developmental competence of porcine embryos can be prevented. In conclusion, DON exposure impairs the developmental ability of porcine embryos by inducing ER stress-mediated apoptosis via IRE1/JNK/CHOP signaling.

Ochratoxin A triggers endoplasmic reticulum stress through PERK/NRF2 signaling and DNA damage during early embryonic developmental competence in pigs

Ochratoxin A (OTA), a mycotoxin found in foods, has a deleterious effect on female reproduction owing to its endocrine-disrupting activity mediated through endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production. However, the mechanisms of OTA-induced ER stress in pig embryos during in vitro culture (IVC) are not yet fully understood. In the present study, porcine embryos were cultured for two days in an IVC medium supplemented with 0.5, 1.0, and 5.0 μM OTA, which led to an OTA-induced reduction in the developmental rate of blastocysts. The mRNA-seq transcriptome analysis revealed that the reduced blastocyst development ability of OTA-exposed porcine embryos was caused by ER stress, ultimately resulting in the accumulation of ROS and the occurrence of apoptosis. The expression levels of some UPR/PERK signaling-related genes (DDIT3, EIF2AK3, EIF2S1, NFE2L2, ATF4, EIF2A, and KEAP1) were found to differ in OTA-exposed pig embryos. OTA induces DNA damage by triggering an increase in RAD51/γ-H2AX levels and suppressing p-NRF2 activity. This effect is mediated through intracellular ROS and superoxide accumulation in the nuclei of porcine embryos. The cytotoxicity of OTA increased the activation of the PERK signal pathways (p-PERK, PERK, p-eIF2α, eIF2α, ATF4, and CHOP) in porcine embryos, with abnormal distribution of the ER observed around the nucleus. Collectively, our findings indicate that ER stress is a major cause of decline in the development of porcine embryos exposed to OTA. Therefore, OTA exposure induces ER stress and DNA damage via oxidative stress by disrupting PERK/NRF2 signaling activity in the developmental competence of porcine embryos during IVC.

A physiological concentration of anandamide promotes the migration of human endometrial fibroblast and the interaction with endothelial cells invitro

INTRODUCTION

The mechanisms that govern fibroblast behavior during the vascular adaptations of the uterus at early pregnancy remain unknown. Anandamide, an endocannabinoid, binds to cannabinoid receptors (CBs), and regulates gestation and angiogenesis. Its tone is regulated by fatty acid amide hydrolase (FAAH) within the uterus. We investigated the role of anandamide in endometrial fibroblasts migration and whether anandamide modulates fibroblasts-endothelial crosstalk.

METHODS

T-hESC and EA.hy926 cell lines were used as models of endometrial stromal and endothelial cells, respectively. T-hESC were incubated with anandamide plus different agents. Migration was tested (wound healing assay and phalloidin staining). Protein expression and localization were studied by Western blot and immunofluorescence. To test fibroblast-endothelial crosstalk, EA.hy926 cells were incubated with fibroblast conditioned media obtained after T-hESC migration.

RESULTS

Anandamide 1 nM increased T-hESC migration via CB1 and CB2. Cyclooxygenase-2 participated in anandamide-stimulated fibroblast migration. Prostaglandin F2alpha, and not prostaglandin E2, increased fibroblast wound closure. CB1, CB2, cyclooxygenase-2 and FAAH were expressed in T-hESC. Anandamide did not alter cyclooxygenase-2 localization but induced its cytoplasmic and nuclear expression through CB1 and CB2. URB-597, a FAAH selective inhibitor, also increased T-hESC migration via both CBs, and augmented cyclooxygenase-2 expression. Conditioned media from anandamide-induced T-hESC wound healing closure stimulated endothelial migration and did not alter their proliferation. Soluble factors from cyclooxygenase-2 were secreted by T-hESC and participated in T-hESC-induced EA.hy926 migration. Although anandamide-conditioned media augmented in EA.hy926 the expression of γH2AX, a marker of DNA damage, cyclooxygenase-2 was not involved in this effect.

DISCUSSION

Our results provide novel evidence about an active role of anandamide on endometrial fibroblast behavior as a mechanism regulating uterine vascular adaptations in early gestation.

Rapamycin encourages the maintenance of mitochondrial dynamic balance and mitophagy activity for improving developmental competence of blastocysts in porcine embryos in vitro

Rapamycin induces autophagosome formation and activity during oocyte maturation, improved fertilization ability of matured oocytes, and early embryonic developmental competence. However, potential changes in mitochondrial fission and mitophagy via regulation of autophagy in early porcine embryonic development have not been previously studied. Here, we investigated embryonic developmental ability and quality of porcine embryos 2 days after in vitro fertilization and following treatment with 1 and 10 nM rapamycin. As a results, 1 nM rapamycin exposure significantly improved (p < 0.05) blastocyst developmental competence compared to that in nontreated embryos (nontreated: 26.2 ± 5.7% vs. 1 nM rapamycin: 35.3 ± 5.1%). We observed autophagic (LC3B) and mitochondrial fission protein expression (dynamin-related protein-1 [DRP1] and pDRP1-Ser616) at the cleavage stage of 1 and 10 nM rapamycin-treated porcine embryos, using Western blot and immunofluorescence analyses. Interestingly, 1 nM rapamycin treatment significantly improved autophagy formation, mitochondrial activation, and mitochondrial fission protein levels (p < 0.05; p-DRP1 [Ser616]) at the cleavage stage of porcine embryos. Additionally, mitophagy was significantly increased in blastocysts treated with 1 nM rapamycin. In conclusion, our results suggest that rapamycin promotes blastocyst development ability in porcine embryos through mitochondrial fission, activation, and mitophagy in in vitro culture.

Effect of the Rho-Kinase/ROCK Signaling Pathway on Cytoskeleton Components

The mechanical properties of cells are important in tissue homeostasis and enable cell growth, division, migration and the epithelial-mesenchymal transition. Mechanical properties are determined to a large extent by the cytoskeleton. The cytoskeleton is a complex and dynamic network composed of microfilaments, intermediate filaments and microtubules. These cellular structures confer both cell shape and mechanical properties. The architecture of the networks formed by the cytoskeleton is regulated by several pathways, a key one being the Rho-kinase/ROCK signaling pathway. This review describes the role of ROCK (Rho-associated coiled-coil forming kinase) and how it mediates effects on the key components of the cytoskeleton that are critical for cell behaviour.