Pressure induced nucleus DNA fragmentation

Abstract

Purpose The present study was designed to investigate the impact of pressure on nuclear DNA integrity in viable cells of mouse blastocysts. Methods The blastocysts of hybrid F1 females [(C57Bl/10 J × CBA-H);N=15] aged 2-3 months were exposed into the pressure impulse lasting~0.021 s and characterized by a positive pressure peak of~76 mmHg. The nuclear DNA fragmentation index of mouse blastocysts was assessed by TUNEL assay within 60 s after exposure to pressure impulse. Results The mean nuclear DNA fragmentation index was significantly higher in the experimental group (83%) than in the control group (19.7%); p<0.001. Conclusion(s)A low magnitude pressure impulse can induce nuclear DNA fragmentation in mouse blastocysts. The compression and decompression forces appearing during pressure fluctuations are responsible for the observed DNA shearing.

Influence of embryo transfer on embryo preimplantation development

“…Therefore, the ET at the early stages of embryo development seems to be more favorable to the embryo viability than its later counterpart, unless the pressure-based catheters are used. The results of the present and the previous experiments demonstrated that the physical conditions created during ET are able to injure vital cell structures (2)(3)(4)11). The application of the microsyringe with a relatively small plunger diameter allowed us to reduce the pressure generated during ET (Fig.…”

“…According to recent studies, pressure fluctuations, depending on their magnitude, can cause intracellular enzymes inactivation (8,9), cytoskeletal disorganization (10), and DNA fragmentation (11,12), in addition to influencing cell membranes integrity (13,14) FIGURE 1…”

Fluid dynamics during embryo transfer

“…With high enough injection speeds, the shear stress can be strong enough to injure the vital cell's organs and impair embryo viability. A recent study indicated that fast ET, with an injection speed of the transferred volume of more than 1 m/sec, could trigger both morphological and apoptotic changes in mouse blastocysts (4,8). Alternatively, reduction of the injection speed to less than 0.1 m/sec allowed to avoid morphological changes and significantly decreased apoptosis in embryos (4).…”

Evidence for Compression ofEscherichia coliK12 Cells under the Effect of TiO2Nanoparticles

“…There are published data pointing out that compression can influence on the nucleus DNA integrity. The fact that even relatively low pressure induce DNA fragmentation was demonstrated in the isolated DNA samples by Schriefer et al and in viable cells of mouse blastocysts by Grygoruk et al DNA fragments after photocatalysis treatment of E. coli cells by TiO 2 NPs was detected by Pigeot-Ŕemy et al Probably, compression of DNA and subsequent destruction of its structure and integrity as a result of TiO 2 NPs action makes it unable to perform its biological functions and is the primary cause of cell death.…”