Live motile sperm sorting device for enhanced sperm-fertilization competency: comparative analysis with density-gradient centrifugation and microfluidic sperm sorting.

PURPOSE: A live motile sperm sorting device (LensHooke® CA0) developed to prevent the deleterious effects of centrifugation was evaluated comparatively with conventional density-gradient centrifugation (DGC) and microfluidic-based device (Zymot) in sperm selection. METHODS: Semen samples from 239 men were collected. CA0 under different incubation intervals (5, 10, 30, and 60 min) and temperatures (20, 25, and 37℃) was conducted. The sperm quality in CA0-, DGC-, and Zymot-processed samples was then comparatively evaluated. Semen parameters included concentration, motility, morphology, motion kinematics, DNA fragmentation index (DFI), and the rate of acrosome-reacted sperm (AR). RESULTS: Total motility and motile sperm concentration increased in a time- and temperature-dependent manner and the total motility peaked for 30 min at 37℃. In paired analysis, CA0 showed significantly higher total motility (94.0%), progressive motility (90.8%), rapid progressive motility (83.6%), normal morphology (10.3%), and lower DFI (2.4%) and AR (4.7%) than the other two methods in normozoospermic samples (all p < 0.05). For non-normozoospermic samples, CA0 had significantly better results than the other two methods (total motility 89.2%, progressive motility 80.4%, rapid progressive motility 74.2%, normal morphology 8.5%, DFI 4.0%, and AR 4.0%; all p < 0.05). CONCLUSION: CA0 yielded spermatozoa with enhanced sperm fertilization potentials; DFI was minimized in samples processed by CA0. CA0 was effective for both normal and abnormal semen samples due to its consistent selection efficiency.

4-Aminobiphenyl inhibits the DNA homologous recombination repair in human liver cells: The role of miR-630 in downregulating RAD18 and MCM8.

4-Aminobiphenyl (4-ABP), a well-known human carcinogen, has been shown to cause oxidative DNA damage and induce miR-630 expression in HepG2 cells treated with 18.75 µM-300 µM for 24 h. However, the underlying mechanism regarding the epigenetic regulation of miR-630 on DNA damage repair in liver cells is still not understood and needs to be investigated. In present study, our results showed that miR-630 was upregulated, resulting in mediating a decrease of DNA homologous recombination (HR) repair in L-02, HepG2 or Hep3B cells. Results from a luciferase reporting experiment showed that RAD18 and MCM8 were the potential targets of miR-630 during DNA damage induction. The downregulation of RAD18 or MCM8 by miR-630 was accompanied by inhibition of HR repair. Conversely, inhibiting miR-630 enhanced the expression of RAD18 and MCM8, and rescued HR repair. Additionally, we proved that the transcription factor CREB was related to miR-630 biogenesis in liver cells. Moreover, the levels of CREB, miR-630 expression, and double-strand breaks (DSBs) were attenuated by 5 mM N-acetyl-L-cysteine (NAC) pretreatment, indicating that reactive oxygen species (ROS)-dependent CREB-miR-630 was involved in DSB repair. These findings indicated that the ROS/CREB/-miR-630 axis plays a relevant role in the regulation of RAD18 and MCM8 in HR repair, which may facilitate our understanding of molecular mechanisms regarding the role of miR-630 downregulating DNA damage repair in liver cells.

Se-Allylselenocysteine induces autophagy by modulating the AMPK/mTOR signaling pathway and epigenetic regulation of PCDH17 in human colorectal adenocarcinoma cells.

SCOPE: Selenium (Se)-conjugated compounds have been established as anti-carcinogenic compounds. The use of chemicals as cancer chemotherapeutic agents to induce programmed cell death (PCD) involves genetic and epigenetic modifications. In this study, we investigated the underlying molecular mechanisms of Se-allylselenocysteine (ASC)-induced PCD and protocadherin 17 (PCDH17) expression in HT-29 cells. METHODS AND RESULTS: Cell viability analysis indicated that the ability of ASC to induce cancer cell death was greater than that of Se-methylselenocysteine in colorectal cancer cells. ASC also decreased global DNA methylation levels via downregulation of DNA methyltransferase 1 expression. The autophagic cell death is the cause in ASC-induced cytotoxicity that was inhibited by pretreatment with autophagy inhibitor. At the molecular level, ASC induced PCDH17 expression through decreased PCDH17 promoter hypermethylation. PCDH17 is also an important role in ASC-induced autophagy by HT-29 transfected with PCDH17 shRNA or expression plasmid. Our western blot analysis showed that ASC significantly induced autophagy via the AMPK/mTOR pathway that was also regulated PCDH17 expression. Additionally, we used the HT-29 tumor xenograft models to confirm the ability of ASC inhibited tumor growth. CONCLUSION: These results reveal that ASC is an effective inducer of autophagy through regulating the AMPK/mTOR and PCDH17 expression via epigenetic modification.