Effects of cytochalasin B on DNA methylation and histone modification in parthenogenetically activated porcine embryos

Abstract

DNA methylation and histone modification play important roles in the development of mammalian embryos. Cytochalasin B (CB) is an actin polymerization inhibitor that can significantly affect cell activity and is often used in studies concerning cytology. In recent years, CB is also commonly being used in in vitro experiments on mammalian embryos, but few studies have addressed the effect of CB on the epigenetic modification of embryonic development, and the mechanism underlying this process is also unknown. This study was conducted to investigate the effects of CB on DNA methylation and histone modification in the development of parthenogenetically activated porcine embryos. Treatment with 5 μg/mL CB for 4 h significantly increased the cleavage rate, blastocyst rate and total cell number of blastocysts. However, the percentage of apoptotic cells and the expression levels of the apoptosis-related genes BCL-XL, BAX and CASP3 were significantly decreased. Treatment with CB significantly decreased the expression levels of DNMT1, DNMT3a, DNMT3b, HAT1 and HDAC1 at the pronuclear stage and promoted the conversion of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC). After CB treatment, the level of AcH3K9 was upregulated and the level of H3K9me3 was downregulated. When combined with Scriptaid and 5-Aza-Cdr, CB further improved the embryonic development competence and decreased the expression of BCL-XL, BAX and CASP3 In conclusion, these results suggest that CB could improve embryonic development and the quality of the blastocyst by improving the epigenetic modification during the development of parthenogenetically activated embryos.

DNA methylation regulated by ascorbic acids in yak preimplantation embryo helps to improve blastocyst quality

“…Compared with the untreated group, treatment with a AA concentration of 50 μg/ml can effectively inhibit apoptosis and improve the developmental ability of the embryo, which is similar to studies of cattle, mouse and porcine embryos (Chawalit et al, ; Chen et al, ; Huang et al, ; Wang et al, ). In addition, in the blastocyst stage, 50 μg/ml of AA treatment significantly inhibited the expression of proapoptotic genes BAX and promoted the expression of antiapoptotic genes BCL‐2 , this is similar to the results in pig embryos (Hou et al, ). The difference is that the 50 μg/ml AA in this experiment has no significant increase in the cleavage rate and blastocyst rate of yak embryos but significantly increases the cell number in the blastocyst stage.…”

“…In this study, the quality of blastocysts was evaluated by two (Chawalit et al, 2012;Chen et al, 2016;Huang et al, 2011;Wang et al, 2002). In addition, in the blastocyst stage, 50 μg/ml of AA treatment significantly inhibited the expression of proapoptotic genes BAX and promoted the expression of antiapoptotic genes BCL-2，this is similar to the results in pig embryos (Hou et al, 2016).…”

“…At the beginning of embryonic development, DNMT1 converts hemimethylated cytosine to 5 methylcytosine to restored to full methylation, and DNMT3a and DNMT3b regulate DNA de novo methylation by their own activity during subsequent embryonic development (Bestor, Laudano, Mattaliano, & Ingram, ; Okano, Xie, & Li, ). On one hand, the knockout and overexpression of DNMT1 will result in early apoptosis and incomplete DNA methylation reprogramming during embryonic development, whereas knockdown or overexpression of DNMT3a and DNMT3b will result in developmental defects in embryos and the deletion of imprinted genes (Hou et al, ; Ju, Rui, Lu, Lin, & Guo, ; Masahiro et al, ). On the other hand, the pharmacological dose of ascorbic acid in the treatment of human melanoma has an important relationship with the activity of DNMT (Venturelli et al, ).…”

Helicobacter pylori regulates ILK signaling pathways to influence autophagy in gastric epithelial cells

“…Small GTP-binding proteins of the Rho family, such as Rac-1 and RhoA, can regulate the stability of newly formed actin laments and actin dynamics by regulating downstream signal molecules (Ivanovska et al, 2013;Xu et al, 2016;Yuan et al, 2017). The Rho GTPase Rac1 can bind to and modulate the activation of PAK1 (Xu et al, 2014), which can also interact with LIMK1 to stabilize actin lament dynamics and inhibit downstream co lin, an actin depolymerization agent (Hou et al, 2016). Co lin-1 acts as a terminal effector of the Rho GTPases signaling cascade, which regulates actin dynamics by increasing the depolymerization of F-actin laments (Wang et al, 2015).…”

Prevalence of Hepatitis B, C and Tuberculosis in Under Privileged Children (Orphans) of District Bagh, Azad Jammu and Kashmir

“…Furthermore, during animal cloning, the addition of a cell permeable mycotoxin, cytochalasin B (CB), is also an integral part of activation protocol. CB prevents release of 2 nd polar body by inhibiting the polymerization process and disrupting the actin filaments (Modlinski, 1980;Hou et al, 2016). This inhibition is important to maintain the diploid nature of oocyte during the parthenogenesis process.…”