Flavonoids have a range of biological activities, including anti-allergic, anti-inflammatory, anti-microbial, and anti-cancer activities, as demonstrated by in vitro studies. In this study, we investigated whether luteolin can be applied to suppression of lipopolysaccharide (LPS)-stimulated inflammatory responses in murine macrophages. Luteolin was found to reduce nitric oxide (NO) production in LPS-stimulated Raw 264.7 cells. In addition, expression of inducible nitric oxide synthetase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokine tumor necrotic factor-α (TNF-α) at the mRNA and protein levels were decreased. These inhibitory effects were found to be caused by the blockade of nuclear factor kappa-light- chain-enhancer of activated B cells (NF-κB) activation and phosphorylation of mitogen-activated protein (MAP) kinase family, extracellular signal-regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 MAP kinase. In addition, pre-treatment with luteolin resulted in reduced ganglioside expression levels and inhibited expression of GT1b in Raw 264.7 cells. On the basis of these observations, we suggest that luteolin has potential as an anti-inflammatory drug candidate, and ganglioside GT1b may play a role in the inflammatory process.

Despite of the presence of estradiol-17β (E2) in ovarian follicles, its role(s) in in vitro maturation (IVM) is still largely unknown, especially in pigs. Thus, the current study was conducted to investigate the effect of E2 on in vitro maturation (IVM) of porcine oocytes and subsequent preimplantation development using in vitro fertilization (IVF)- or somatic cell nuclear transfer (SCNT)-derived embryos. To define the effects of E2 on IVM and early embryogenesis, porcine oocytes were matured in the presence or absence of E2, fertilized in vitro and cultivated to blastocyst stage. Compared to control group, the production of MII oocytes was significantly increased by treatment with E2, accompanying with the increase in MPF content and ERK phosphorylation, and monospermic fertilization and blastocyst development rates were also greatly elevated in the E2-treated oocytes. In addition, the advantageous role of E2 was also found in blastomere survival, which was further evidenced by both elevation of anti-apoptotic transcript Bcl-XL and decrease of pro-apoptotic transcript Bax. Furthremore, these positive effects of E2 were highly reproducible in early development of SCNT embryos. Collectively, the current study strongly suggests that E2 can be used as a efficient IVM supplement leading to successful nuclear/cytoplasmic maturatioin in pigs.

Successful early embryogenesis of somatic cell nuclear transfer (SCNT) embryos is very important to produce cloned animals. However, poor preimplantation development of SCNT embryos has been a major obstacle to the generation of cloned animals due to a lack of understanding of developmental events and underlying mechanism(s). In the current study, we show that production of SCNT embryos with high developmental competence is dependent on the fusion method. Electrofusion causes spontaneous egg activation, accompanied by an increase in intracellular Ca2+ and improper nuclear remodeling, whereas Sendai virus (SV)-mediated fusion greatly reduces these events. In addition, SV-SCNT increased the blastocyst development rate and trophectoderm cell number compared to electrofusion-mediated SCNT (E-SCNT). In particular, expression of ER stress-associated genes and blastomere apoptosis were significantly increased in E-SCNT embryos, which could be alleviated by inhibition of ER stress or by using the SV-mediated fusion method. Taken together, these results strongly suggest that SV is a useful fusion material for improvement of preimplantation development of SCNT embryos through reduction of ER stress-associated apoptosis.