ABSTRACT
To investigate the physiological response of IAA (indoleacetic acid) to Trichosanthes kirilowii under aluminum stress and the mitigation of DNA damage, the effects of IAA (0, 10, 25, 50, 75 µmol·L-1 denoted by I0, I10, I25, I50 and I75, respectively) on antioxidant enzyme activity, malondialdehyde (MDA), photosynthetic characteristics, root activity, chlorophyll content and DNA damage of two varieties of T. kirilowii under 300 and 800 µmol·L-1 aluminum environment (denoted by Al300 and Al800, respectively) were examined in hydroponic culture experiments with Hebei Anguo (aluminium tolerant variety) and Zhejiang Puyang Trichosanthes kirilowii (aluminum sensitive variety). The results showed that the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), photosynthesis ability, and root activity of both varieties were inhibited to different degrees by aluminum stress, MDA content was significantly increased, and DNA damage was aggravated. The maximum increase of SOD, CAT and POD activities in Anguo and Puyang T. kirilowii under aluminum stress by IAA application were 15.0%, 31.2%, 72.3% and 13.8%, 26.9%, 26.4%, respectively, chlorophyll content increased by 49.9% and 17.9%, MDA accumulation decreased by 39.2% and 22.4% and fluorescence parameters were significantly improved. The treatment of 25 µmol·L-1 IAA significantly increased root activity by 159.1% and 90.9%, while 50 µmol·L-1 IAA effectively slowed the DNA tailing phenomenon in roots, with the product (OTM) value of tail DNA percentage content and tail moment being decreased by 27.6%. 10-50 µmol·L-1 IAA could effectively improve the physiological activity of T. kirilowii under aluminum stress and slow the degree of DNA damage. The tolerance of Anguo variety to aluminum stress was stronger than that of Puyang variety.
Subject(s)
Trichosanthes , Aluminum , Catalase , DNA Damage , Seedlings , Stress, Physiological , Superoxide DismutaseABSTRACT
Our previous study has demonstrated cyclosporin A (CsA) promotes the migration and invasiveness of human first-trimester trophoblast cells in vitro. Here, we further investigated the effect of CsA on the early implantation in vitro of mouse embryo. Female C57 mice were superovulated and mated, and then two-cell embryos were harvested from the oviducts and sequentially cultured in vitro in G1 and G2 media with 0, 0.1, 1.0 or 10 µM of CsA. Blastocyte formation, blastocyte cell number and apoptosis, embryo hatching were assessed in 4-6 dpc. The adhesion and stretching growth of hatched embryos in laminin coated dishes were evaluated from 5 dpc to 8 dpc, and the expressions of implantation serine proteinase 1 (ISP1), integrin (itg) ß3 and matrix metalloproteinase (MMP)-9 were determined by real time PCR and immunofluorescence, respectively. We showed there was no significant difference in blastocyst formation rates, hatching rates, number of whole embryonic cells, apoptotic cells, and distribution of inner cell masses (ICMs) and trophoblasts (TB) between the CsA- and control-treated groups. Expression of ISP1 mRNA was unaffected on 5 dpc. After hatching, adhesion rate of 7 dpc significantly increased in 0.1 and 1.0 µM of CsA treatment, and embryo area of 8 dpc stretch growing on laminin were increased in 1.0 µM of CsA. The mRNA and protein expression of itgß3 and MMP-9 on 7 dpc blastocyst were up-regulated. In conclusion, CsA in low dosage up-regulates itgß3 and MMP-9 expression, and enhances embryonic adhesion and invasion, which is beneficial to the embryo implantation.