Expression of miR-Let-7a, miR-15a, miR-16-1, and their target genes in fresh and vitrified embryos and its surrounding culture media for noninvasive embryo assessment.

microRNAs (miRNAs) play a critical role in implantation and development of mouse embryos. In this study, we aim to evaluate the possibility of miRNAs as potential biomarkers in the blastocyst culture to assess embryo quality. We also intend to investigate whether improved clinical outcomes of vitrified embryos agree with altered miRNA expressions. Mouse embryos from in vitro fertilization were vitrified at the two-cell stage. After thawing, the embryos were individually cultured and developed to the blastocyst stage. We used quantitative real-time polymerase chain reaction to evaluate miRNA expression levels in both vitrified and fresh groups, and culture medium (CM). The fibronectin binding assay was performed to examine for blastocyst attachment. The findings showed reduced expressions of miR-16-1 (0.2 ± 0.06) and miR-Let-7a (0.65 ± 0.1) after vitrification compared to fresh embryos. We observed significant upregulation of the target genes Vav3 (4.33 ± 0.25), integrin ß-3 (Itg ß3; 4.73 ± 0.2), and Bcl2 (2.29 ± 0.16) in the vitrified embryos compared to the fresh groups. Evaluation of blastocyst CM showed upregulation of miR-Let-7a (15.68 ± 0.89), miR-16-1 (16.18 ± 0.75), and miR-15a (13.36 ± 0.73) in the vitrified group in comparison to the fresh blastocysts (P < .05). The expression levels of miR-16-1 (3.28 ± 0.63), miR-15a (5.91 ± 0.38), and miR-Let-7a (9.07 ± 0.6) in CM of the vitrified blastocysts conducted on fibronectin were significantly higher than the fresh group (P < .05).This study showed that vitrification of embryos changes implantation and proliferation biomarkers. In addition, upregulated miRNAs in CM could be potentially used for noninvasive early assessment of embryo quality.

The effect of dietary oils on cecal microflora in experimental colitis in mice.

OBJECTIVES: In spite of growing evidence indicating the benefits of probiotics, the effects of different dietary oils on intestinal microflora and probiotics have not been elucidated. This study aimed to examine the effects of different dietary oils on intestinal microflora in an experimental model of colitis. METHODS: Eight-week mice were fed isocaloric diets varying only in fat composition for 4 weeks. The oils used were fish oil, canola oil, safflower oil, and chow diet containing beef tallow. Colitis was induced by intracolonic administration of acetic acid on day 21. The inflammation and fecal microflora and serum lipid profiles were evaluated 1 week after induction. RESULTS: Inflammation was highest in the chow diet group followed by safflower, canola, and fish oil fed groups, respectively. The number of fecal bacteroideceae was greater, whereas the number of fecal bifidobacteria was lower in mice fed beef tallow than the other ones. In addition, fish oil reduced the plasma level of triacylglycerole significantly. CONCLUSION: Polyunsaturated fatty acids (PUFAs) can affect intestinal microflora increasing the number of probiotics. PUFAs might be recommended in addition to probiotics for the prevention and/or maintenance treatment of colitis.