The Effect Of Formaldehyde On MiRNA-21 And Its Downstream Proteins PTEN, TIMP-3, RECK In The Liver

Objective The effect of formaldehyde on mi RNA-21 and the downstream proteins of phosphatase and tensin homolog(PTEN), the tissue inhibitors of metalloproteinase 3(TIMP-3) and reversion-inducing cysteine-rich protein with Kazal motifs(RECK) in the liver of mice.Methods Forty female Kunming mice were randomly divided into three formaldehyde groups(low-, medium- and high-concentration groups) and a control group. The three formaldehyde groups were intraperitoneally injected with different concentrations of formaldehyde at 10:00 am daily. The control group was injected with equal volume of normal saline. Real-time quantitative PCR(RT-PCR) was used to detect the changes of expression of mi RNA-21 after 30 d. Immunohistochemistry and western blot were used to test the expression of PTEN, TIMP-3 and RECK in the liver.Results The relative expression levels of mi RNA-21 in low-, medium-, and high-concentration groups, compared with that in the control group, were 1.16±0.18, 1.61±0.29 and 2.48±0.49 respectively. There were significant differences between different groups(F=38.02, P﹤0.0001). The expression values of PTEN in the control group,low-, medium-, and high-concentration groups were 1.44±0.057,1.15±0.054,0.81±0.025 and 0.62±0.065 respectively. There were significant differences between different groups(F=145.4,P﹤0.0001). The expression values of TIMP-3 in the control group, low-, medium-, and high-concentration groups were 1.30±0.058, 1.04±0.083, 0.85±0.070 and 0.23±0.067 respectively. There were significant differences between different groups(F=125.8, P﹤0.0001). The expression values of RECK in the control group, low-, medium-, and high-concentration groups were 1.24±0.057, 1.11±0.056,0.68±0.042 and 0.35±0.066 respectively. There were significant differences between different groups(F=158.7, P﹤0.0001). The relative expression of mi RNA-21 showed a negative association with PTEN, as well as TIMP-3 and RECK(r=-0.919, P=0.081; r=-0.990, P=0.01; r=-0.974, P=0.026, respectively).Conclusion The expression of mi RNA-21 in the liver was significantly increased by formaldehyde in a dose-dependent manner. Moreover, Formaldehyde can decrease the expression of PTEN, TIMP-3 and RECK in the same dose-dependent manner.