The regulative effects of polydatin on toll-like receptor 4 signal transduction pathway in lung ischemia/reperfusion injury in rabbits / 中国应用生理学杂志

<p><b>AIM</b>To investigate protective effects of polydatin(PD) during lung ischemia/reperfusion in rabbits and its potential mechanisms.</p><p><b>METHODS</b>Rabbit lung model of ischemia/reperfusion (I/R) injury was constituted in vivo. Thirty rabbits were divided into groups randomly: Control (C), I/R, PD group, respectively. Endotoxin (ET) in plasma was analyzed by End-point Chromogenic Assay, the expression of Toll-like receptor 4 (TLR4) mRNA, nuclear factor (NF)-kappaBp65 mRNA, intracellular adhesion molecule-1 (ICAM-1) mRNA were measured by RT-PCR, the morphological changes of lung tissue were observed with hematoxylin-eosin (HE) staining.</p><p><b>RESULTS</b>There was no significant difference in ET concentration of plasma between groups (all of P > 0.05). The expression of TLR-4 mRNA, NF-kappaBp65 mRNA and ICAM-1mRNA in I/R group were significantly increased as compared to C group and PD group, while those expressions in PD group were evidently higher than those in C group (all of P < 0.01). Light microscope showed that the lung pathological injuries in PD group were obviously alleviated as compared to I/R group.</p><p><b>CONCLUSION</b>PD might have a protective effect on lung ischemia/reperfusion injury by down-regulating TLR4 and NF-kappaB expression, then inhibiting the release of mediators of inflammation as ICAM-1.</p>

Protective effects of polydatin against lung ischemia/reperfusion injury and the initial exploration for its mechanism / 中国应用生理学杂志

<p><b>AIM</b>To observe protective effects of polydatin (PD) during lung ischemia/reperfusion injury (LI/RI) and investigate its potential mechanism .</p><p><b>METHODS</b>Rabbit lung model of ischemia/reperfusion injury was constituted in vivo. The 40 rabbits were randomly divided into four groups (n = 10): control group (C group), ischemia/reperfusion group (I/R), PD + I/R group (PD) and PD+ polymyxin B (PMB) + I/R group (PMB). The blood specimen gathered at different time points were tested for the content of melondialdehyde (MDA) and the enzyme activity of superoxide dismutase (SOD). The lung tissue sampled at the end of the experiment were assayed for wet/dry weight ratio (W/D), injured alveoli rate (IAR) and observing ultrastructure changes under electron micro scope.</p><p><b>RESULTS</b>(1) The activity of SOD showed a similar time-dependent decline in I/R group and PMB group during I/R, while in PD group this tendency was milder (P < 0.01 vs I/R group). (2) In contrast to the results above, the level of MDA markedly increased in I/R and PMB group, but was slowed down in PD group (P < 0.01 vs I/R group). (3) The value of W/D) and IAR was much higher in I/R and PMB group (P < 0.05 or P < 0.01 vs C group). In PD group, it was decreased (P < 0.01 vs I/R group or PMB group). (4) Electron microscope showed obvious ultrastructure injury brought by LI/RI in I/R group and PMB group, which was greatly attenuated in PD group.</p><p><b>CONCLUSION</b>PD can protect lung from LI/RI, and PKC may participate in its mechanisms.</p>

Effects of safflower injection on cycloxygenase in rabbits lung ischemia/reperfusion injury / 中国应用生理学杂志

<p><b>AIM</b>To observe protective effects of safflower injection (SI) on lung ischemia/reperfusion injury (LIRI) and investigate its potential mechanism.</p><p><b>METHODS</b>Rabbit lung model of ischemia/reperfusion injury was constituted in vivo. The rabbits were randomly divided into three groups: sham-operation group (S group), ischemia/reperfusion group (I/R group) and ischemia/reperfusion plus safflower injection group (SI group). Malondialdehyde (MDA) content, superoxide dismutase (SOD) and xanthine oxidase (XO) activities in serum were measured. The lung tissue sampled at the end of the experiment was assayed for wet/dry weight ratio (W/D), injured alveoli rate (IAR) and ultrastructural changes were observed under electron microscope. The expression of COX-1 and COX-2 were measured by immunohistochemistry (IHC). The expressions of COX-1mRNA and COX-2mRNA were observed by in situ hybridization (ISH).</p><p><b>RESULTS</b>In I/R group, XO and MDA increased and SOD decreased in serum, while the same changes happened in SI group but less severely(P<0.01). The value of W/D and IAR was much higher in I/R group than S group, but decreased in SI group. Electron microscope showed obvious ultrastructural injury brought by LIRI in I/R group, which was greatly attenuated in SI group. The IHC and ISH demonstrated that COX-2 and COX-2mRNA in pulmonary tissue of I/R group were significantly higher than those of SI group (P < 0.01). The difference of COX-1 and COX-1mRNA in pulmonary tissue among the three groups was not significant.</p><p><b>CONCLUSION</b>The ischemia/reperfusion lung injury insults induced the regulation of COX-2 in lung. Safflower injection may attenuate lung ischemia/reperfusion injury through inhibiting cyclooxygenase-2 expression.</p>

Upregulating expressions of hepatic lipopolysaccharide receptors in nonalcoholic steatohepatitic rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>The expression of hepatic lipopolysaccharide (LPS) receptors in a rat nonalcoholic steatohepatitis (NASH) model was studied in order to explore the pathogenesis of NASH.</p><p><b>METHODS</b>Forty-five male SD rats were fed with a high fat diet. These rats were sacrificed after high fat feeding at 8, 12, 16, 24 weeks. Hepatic expressions of CD14 were observed by immunohistochemistry and expressions of TLR4 were detected by RT-PCR. Hepatic expressions and serum levels of TNFa were measured by RT-PCR and ELISA. Some rats fed with normal rat food served as controls.</p><p><b>RESULTS</b>At the 8th week fatty livers appeared, and hepatic expressions of CD14 (25.9+/-1.9) and TLR4mRNA (1.75+/-0.81) were upregulated compared to those in the control group (25.9+/-1.9 vs 12.4+/-0.7, 1.75+/-0.81 vs 0.98+/-0.33, P < 0.01, t > 2.756 and P < 0.05, t > 2.045). The hepatic expressions of the two kinds of receptors increased with the appearance of NASH at week 12 (61.8+/-1.9 and 1.88+/-0.72, P < 0.01, t > 2.756 and P < 0.05, t > 2.045), They reached to their peaks at week 16 (71.5+/-1.3 and 5.64+/-0.87, both P < 0.01 and t > 2.756), and decreased slightly at week 24 (67.7+/-6.6 and 4.98+/-0.72, both P < 0.01 and t > 2.756). Hepatic expressions and serum levels of TNFa also increased starting at week 8, and remained at that high level from week 8 to week 24.</p><p><b>CONCLUSION</b>The hepatic expressions of CD14 and TLR4 were up-regulated gradually in the established rat NASH model. It may be one of the factors responsible for the increase of hepatic sensitivity to LPS injury of the NASH rats and may play an important role in the pathogenesis of NASH.</p>

Expression of uncoupling protein 2 and its relationship to the content of adenosine triphosphate in the nonalcoholic fatty livers of rats fed a high-fat diet / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the expression of uncoupling protein 2 (UCP2) and its relationship to the content of adenosine triphosphate (ATP) in livers of nonalcoholic fatty liver disease (NAFLD) rats fed a fat-rich diet.</p><p><b>METHODS</b>To produce a NAFLD model, a fat-rich diet, consisting of 10% lard oil + 2% cholesterol, was given to Sprague-Dawley rats for a period of 8, 12, 16 and 24 weeks. The normal control rats were fed normal diets. The expressions of UCP2 in the liver were detected by immunohistochemistry and semi-quantitative RT-PCR. The content of ATP of liver was measured by fluorometry.</p><p><b>RESULTS</b>Simple fatty livers were observed in the model group after 8 weeks. From 12 week to 24 week, the livers of the model group rats gradually progressed from simple steatohepatitis to steatohepatitis with pericellular fibrosis. Both immunohistochemistry and semi-quantitive RT-PCR suggested the up-regulated expression of UCP2 in these NAFLD rat livers. The hepatic expression of UCP2 mRNA in the model group was increased with time, and peaked in 24 week by 4.2 times compared to the control group ( t = 16.474, P < 0.01). The ATP content of livers was significantly reduced in the model group compared with the control group at 16 weeks [(2.97+/-0.48) x 10(-8) micromol/g vs. (2.25+/-0.55) x 10(-8) micromol/g, t = 2.419, P < 0.05] and 24 weeks [(2.97+/-0.48) x 10(-8) micromol/g vs. (1.99+/-0.66) x 10(-8) micromol/g, t = 3.248, P < 0.01]. Furthermore, there was a negative correlation between the UCP2 mRNA expression and the content of ATP in the livers of the NAFLD group (r = -0.93, P < 0.01).</p><p><b>CONCLUSIONS</b>The rat model of NAFLD could be replicated sucessfully by feeding a fat-rich diet for 24 weeks, and the mRNA and its protein of UCP2 were expressed un-regulated in livers of NAFLD. The increasing UCP2 might play a role in the reduction of ATP content in livers of the NAFLD rats.</p>

Effect of ligustrazine on the expression and activity of heme oxygenase-1 in the pulmonary ischemia/reperfusion injury in rabbits / 中国应用生理学杂志

<p><b>AIM</b>To explore the effect of ligustrazine injection on the expression of heme oxygenase-1 (HO-1) in rabbits with pulmonary ischemia/reperfusion injury after.</p><p><b>METHODS</b>Single lung ischemia/reperfusion injury animal model was used in vivo. Twenty rabbits were randomly divided into two groups( n = 10, in each), pulmonary ischemia/reperfusion injury (I/R) group and I/R + ligustrazine injection (LGT) group. The tissue slides were stained by immunohistochemistry (IHC) and in situ hybridization (ISH) for HO-1 to detect the expression of HO-1 in lung and to analyze the absorbance, wet to dry ratio of lung tissue weight (W/D) and the injured alveoli rate (IAR) were measured at 180 minutes after lung reperfusion. Meanwhile the lung tissue slide was prepared for electron microscopic observation at 180 minutes after reperfusion.</p><p><b>RESULTS</b>HO-1 expression was upregulated in two groups in the pulmonary endothelial cells, part of pulmonary vascular smooth muscle cells, extima of vessels and epithelial cells of airway, the absorbance was 0.168 +/- 0.016 (0.148 +/- 0.013), 0.186 +/- 0.014 (0.158 +/- 0.012) respectively.The LGTI group showed higher absorbance than those of the I/R group (P < 0.01), lower W/D and IAR values than those of the I/R group (P < 0.01) significantly and lighter abnormal changes of the lung tissue in morphology than those of the I/R group.</p><p><b>CONCLUSION</b>Ligustrazine injection possesses notable protective effects on I/R in rabbits by increasing the expression of HO-1 in lung.</p>

Dynamic changes of plasma levels of prostacycline and thromboxane A2 and their correlation with the severity of hepatic injury in rats with nonalcoholic fatty liver disease / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the dynamic changes of plasma levels of prostacycline (PGI2) and thromboxane A2 (TXA2) and their relationship with the severity of hepatic injury in rats with nonalcoholic fatty liver disease (NAFLD).</p><p><b>METHODS</b>We established a NAFLD model, with a fat-rich diet consisting of 10% lard oil + 2% cholesterol, which was given to Sprague-Dawley rats (n=48) for a period of 8, 12, 16 and 24 weeks. The other rats were fed standard diets and were used as normal controls (n=24). At sacrifice, liver pathology scores were evaluated and plasma levels of PGI2, its stable metabolic product 6-keto-PGF1 alpha and TXA2, and TXB2 were determined by radioimmunoassay.</p><p><b>RESULTS</b>Simple fatty livers were observed in the model group at 8 weeks. From 12 weeks to 24 weeks, the livers gradually progressed from simple steatohepatitis to liver fibrosis. Plasma levels of TXB2 in the model group increased higher than in the control group after 8 weeks [(52.4+/-3.15) ng/L vs (41.1+/-1.45) ng/L] and continued to increase over time, with the highest levels at 24 weeks [(117.7+/-7.47) ng/L]. A strong positive correlation (r=0.537) was seen between plasma TXB2 levels and the severity of liver injury. Plasma 6-keto-PGF1 alpha concentrations decreased in the model group in comparison with the control group after 8 weeks [(31.1+/-1.62) ng/L vs (36.5+/-1.68) ng/L] and continued to decrease over time, with the lowest concentrations at 24 weeks [(3.4+/-2.43) ng/L t=3.77]. A negative correlation was shown between the 6-keto-PGF1 alpha level and the severity of the liver injury.</p><p><b>CONCLUSION</b>A rat model of NAFLD was established successfully by feeding a fat-rich diet for 24 weeks. In this model, the imbalance of plasma PGI2 and TXA2 levels (increased TXB2 and decreased 6-keto-PGF1 alpha levels) may play a role in the pathogenesis of experimental NAFLD.</p>

Change of serum endotoxin level in the progress of nonalcoholic steatohepatitis in rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the role of endotoxin in the pathogenesis of nonalcoholic steatohepatitis (NASH).</p><p><b>METHODS</b>Rat models of NASH were established by giving a fat-riched diet. These rats were sacrificed at the 4th, 8th, 12th, 16th and 24th weeks during the study. The other rats fed with normal diet were taken as normal controls at the same stage during the study. The blood of abdominal aorta was obtained and the levels of serum endotoxin, tumor necrosis factor-alpha (TNF-a), and interleukin-1 beta (IL-1 b) were measured. The expression of CD(14) and lysozyme in rats' livers were detected by immunohistochemistry.</p><p><b>RESULTS</b>Rat models of NASH with liver fibrosis were established successfully. The levels of endotoxin in aorta blood of NASH rats increased significantly at the 24th week (0.23 EU/L 0.06 EU/L vs 0.15 EU/L 0.03 EU/L, t>2.179, p <0.05) while the expression of CD(14) increased from the 4th week, and the Kupffer cells expressing lysozyme were activated, then kept increasing activation through the study. In NASH rats, the levels of serum TNF-a increased from the 8th week (26.39 pg/ml 24.21 pg/ml vs 9.82 pg/ml 9.29 pg/ml, t>2.145, p < 0.05) and serum IL-1beta increased from the 16th week (23.76 pg/ml 21.81 pg/ml vs 6.25 pg/ml 2.98 pg/ml, t>2.145, p<0.05).</p><p><b>CONCLUSION</b>Liver injury results from endotoxin existing in NASH rats which may play an important role in the pathogenesis of NASH by activating Kupffer cells and inducing the production of cytokines, such as TNF-a.</p>

Effect and mechanism of chimonin on pulmonary hypertention of chronic hypoxia and hypercapnic rats / 中国应用生理学杂志

<p><b>AIM</b>To study the effect of chimonin on chronic hypoxia and hypercapnic pulmonary hypertension and to explore its mechanism.</p><p><b>METHODS</b>SD rats were randomly divided into normal control group (A), hypoxic hypercapnic group(B), hypoxic hypercapnia + chimonin group (C). HO-1 and HO-1 mRNA was observed in pulmonary arterioles of rats by the technique of immunohistochemistry and in situ hybridization.</p><p><b>RESULTS</b>(1) mPAP was significantly higher in rats of B group than that of A and C group. Differences of mCAP were not significant in three groups. (2) Blood CO concentration was significantly higher in rats of B group than that of A group, it was significantly higher in rats of C group than that of B group. (3) Light microscopy showed that WA/TA (vessel wall area/total area), SMC (the density of medial smooth muscle cell) and PAMT (the thickness of medial smooth cell layer) were significantly higher in rats of B group than those of A and C group. (4) Electron microscopy showed proliferation of medial smooth muscle cells and collagenous fibers of pulmonary arterioles in rats of B group, and chimonin could reverse the changes mentioned above. (5) HO-1 and HO-1 mRNA in pulmonary arterioles was significantly higher in rats of B group than that of A group, they were significantly higher in rats of C group than that of B group.</p><p><b>CONCLUSION</b>Chimonin can inhibit hypoxic hypercapnia pulmonary hypertension and pulmonary vessel remodeling by further increasing the expression of HO-1 mRNA.</p>

Changes of the brain NSE, S100 and effect of ligustrazine in rats of chronic hypoxia and hypercapnia / 中国应用生理学杂志

<p><b>AIM</b>To investigate the changes of the brain NSE, S100 and ultrastructure and effect of ligustrazine in rats of chronic hypoxia and hypercapnia.</p><p><b>METHODS</b>Thirty rats were randomly divided into three groups: control group (A), hypoxia hypercapnia group (B), hypoxia hypercapnia added ligustrazine group (C). The brain NSE, S100 and ultrastructure were observed in rats using the technique of immunohistochemistry and electronic microscope.</p><p><b>RESULTS</b>(1) The mPAP was significantly higher in rats of group B than that of group A and it was much lower in rats of group C than that of group B. Differences of mCAP were not significant in three groups. (2) Serum NO of group B was significantly lower than that of group A, Serum NO of group C was higher than that of group B. (3) Immunohistochemistry showed the average value of integral light density (LD) of NSE and S100 was significantly much lower in rats of group B than that of group A and it was higher in rats of group C than that of group B. (4) The neuron and astrocyte of group B showed vacuolar degeneration and the myelin sheath showed separate. Damage of neuron is alleviated in rats of group C.</p><p><b>CONCLUSION</b>The hypoxia hypercapnia could induce damage of neuron and astrocyte in rats. The ligustrazine may be useful in protecting against hypoxia hypercapnia brain damage.</p>

Effects of ligustrazin on lipid peroxidation during hepatic ischemia reperfusion injury / 中国应用生理学杂志

<p><b>AIM</b>To explore the role of ligustrazin on dynamic changes of lipid peroxidation in hepatic ischemia/reperfusion injury (HIRI) and its mechanism.</p><p><b>METHODS</b>The HIRI model was used. Twenty rabbits were randomly divided into control group (n = 10) and ligustrazin group (n = 10). The xanthine oxidase (XO) activity, superoxide dismutase (SOD) activity,malondialdehyde (MDA) content and glutamic pyruvic transaminase (GPT) activity in plasma were observed before ischemia and at ischemia 25 min, reperfusion 25 min, reperfusion 60 min and reperfusion 120 min.</p><p><b>RESULTS</b>The XO activity, SOD activity, MDA content and GPT activity of ligustrazin group, as compared with control group, showed significant differences (P < 0.05 or P < 0.01) at total time points of reperfusion.</p><p><b>CONCLUSION</b>Ligustrazin has notable anti-lipid peroxidation effect on HIRI, which is due to its inhibiting the generation of oxygen free radicals and its strengthening scavenging of oxygen free radicals.</p>