Study the effects of Salvia miltiorrhiza monomer IH764-3 on the expression of matrix metalloproteinase in lungs of rats exposed to Paraquat (PQ) / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the expression of the matrix metalloproteinase 2 (MMP-2) and membrane-type 1 metalloproteinase (MT1-MMP) in lung of rats exposed to paraquat (PQ) and the effects of Salvia miltiorrhiza monomer IH764-3 on above expression.</p><p><b>METHODS</b>Ninety adult healthy Sprague-Dawley (SD) rats were randomly divided into the control group (group A, 6 rats), the exposure group (group B, 42 rats) and the group treated by Salvia miltiorrhiza monomer IH764-3 (group C, 42 rats). The group B and C were treated intragastrically with 1ml of PQ (50 mg/kg), and the group A was treated intragastrically with normal saline. The group C was treated intraperitoneally with 1 ml Salvia miltiorrhiza monomer IH764-3 at the dose of 40 mg/kg a day. The group A and B were treated intraperitoneally with 1 ml normal saline day. The expression of MMP-2 and MT1-MMP was detected on the 1st, 3rd, 7th, 14th, 21st, 28th and 35th days after exposure for all groups.</p><p><b>RESULTS</b>As compared with the expression level (0.305 ± 0.045) of MMP-2 mRNA in group A, the expression levels of MMP-2 mRNA in Group B significantly increased, which were 0.654 ± 0.077, 0.623 ± 0.051, 0.637 ± 0.024, 0.533 ± 0.043 and 0.552 ± 0.050 on the 1st, 3rd, 7th, 14th, 21st days after exposure, respectively (P < 0.01). As compared with group A, the the expression levels of MMP-2 mRNA on the 1st, 3rd, 7th days in Group C slightly increased, but the expression levels of MMP-2 mRNA on the 1st, 3rd, 7th, 14th, 21st days in Group C were 0.523 ± 0.074, 0.567 ± 0.097, 0.514 ± 0.058, 0.359 ± 0.018 and 0.374 ± 0.020, respectively, which were significantly lower than those in group B (P < 0.01). As compared with the expression level (0.391 ± 0.058) of MT1-MMP mRNA in group A, the expression levels of MT1-MMP mRNA in Group B significantly increased, which were 0.796 ± 0.021, 0.762 ± 0.043, 0.590 ± 0.010, 0.803 ± 0.076 and 0.680 ± 0.034 on the 1st, 3rd, 7th, 14th and 21st days after exposure, respectively (P < 0.01). As compared with group A, the expression levels of MT1-MMP mRNA in Group C significantly increased, which were 0.594 ± 0.010, 0.653 ± 0.044 and 0.564 ± 0.009 on the 1st, 3rd and 21st days after exposure, respectively (P < 0.01). The expression levels of MT1-MMP mRNA in Group C were significantly lower than those in group B (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>The expression changes of MMP-2 and MT1-MMP genes of lungs in rats intragastrically exposed to PQ could result in the unbalance the synthesis and degradation of ECM, which may be a cause of lung fibrosis. The Salvia miltiorrhiza monomer IH764-3 could affect the expression of MMP-2 and MT1-MMP genes to a certain extent, resulting in the reduction of lung fibrosis.</p>

Expression of nuclear factor kappaB and tumor necrosis factor α in lung tissue of paraquat poisoned rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the expression of nuclear factor kappa B (NF-kgr;B) and tumor necrosis factor α (TNF-α) in lung tissue of acute paraquat poisoned rats.</p><p><b>METHODS</b>68 male Wistar rats were randomly divided into 2 groups: the control group (n = 8), the intoxication group (n = 60). On the 1st, the 3rd, the 7th, the 14th and the 28th day after intoxication, the expression of NF-κB p65 and TNF-α in lung tissue were detected by LSAB immunohistochemistry (IH) staining. Meanwhile, the level of malondialdehyde (MDA) in plasma, and lung homogenate, the content of malondialdehyde (HPY) in lung homogenate were detected.</p><p><b>RESULTS</b>The levels of MDA in plasma on the 1st, the 3rd, the 7th day and in lung homogenate on the 1st, the 3rd day of the intoxication group [in plasma: (10.15 ± 3.15), (6.97 ± 1.65) and (5.44 ± 0.66) nmol/ml; in lung homogenate: (10.20 ± 2.43), (10.71 ± 171) nmol/ml] were significantly higher than that of the control group [in plasma: (3.84 ± 1.04) nmol/ml, in lung homogenate: (7.66 ± 0.66) nmol/ml]. The content of HPY in lung homogenate on the 14th and the 28th day after intoxication [(19.98 ± 2.86), (26.06 ± 4.06) µg/0.1 g lung homogenate] were higher than that of the control group [(8.80 ± 1.26) µg/0.1 g lung homogenate] significantly. The expression of NF-κB p65 and TNF-α in lung tissue were both significantly increased on the first day and the 3rd day of the intoxication group compared with the control group and weakened obviously after the 7th day.</p><p><b>CONCLUSION</b>Acute paraquat poisoning can induce increased expression of both NF-κB p65 and TNF-α in lung tissue; the enhanced activity of NF-κB may take part in the process of pulmonary injury in PQ poisoning.</p>

Changes of p38 MAPK and nuclear factor-kappa B in lung tissue of acute paraquat poisoned rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate NF-kappaB activity and the expression of phosphorylated p38 MAPK protein in lung tissue of acute paraquat poisoned rats and the effect of MT.</p><p><b>METHODS</b>One hundred and twenty-eight Sprague-Dawley (SD) rats were randomly divided into three experimental groups: poisoned group, MT group and control group. On the 1st, the 3rd, the 7th and the 14th day after exposure, levels of malondialdehyde (MDA) in serum were detected, NF-kappaB activity in the lung tissues was assessed by electrophoresis mobility shift assay (EMSA), the expression of the phosphorylated p38 MAPK was evaluated by Western blot method, the lung pathological changes of rats were observed.</p><p><b>RESULTS</b>The level of malondialdehyde (MDA) in serum increased significantly in poisoned group on the 1st day (4.45 +/- 1.23), the 3rd day (3.77 +/- 1.12) and the 7th day (2.84 +/- 0.96) nmol/ml compared with that in control group (1.36 +/- 0.52) nmol/ml (P < 0.01). There was a significant decrease in MT group on the 1st day (2.68 +/- 0.85), the 3rd day (1.97 +/- 0.74) and the 7th day (1.53 +/- 0.62) nmol/ml compared with poisoned group (P < 0.05). The expression of the phosphorylated p38 MAPK and NF-kappaB activity in lung tissue of poisoned group significantly increased compared with control group (P < 0.01). There was a significant decrease in NF-kappaB activity and expression of the phosphorylated p38 MAPK in the lung tissues in MT group compared with poisoned group (P < 0.05).</p><p><b>CONCLUSION</b>NF-kappaB and p38 MAPK could play an important role in lung injury of poisoned rats. MT may inhibit the expression of NF-kappaB and phosphorylated p38 MAPK, and therefore might have the therapeutical effect on acute paraquat poisoning.</p>