Protective effect of Astragalus membranaceus on intestinal mucosa reperfusion injury after hemorrhagic shock in rats

AIM： To study the protective effect of Astragalus rnernbranaceus on intestinal mucosa reperfusion injury and its mechanism after hemorrhagic shock in rats. METHODS： A total of 32 SD rats were randomly divided into four groups （n = 8, each group）： normal group, model group, low dosage group （treated with 10 g/kg Astragalus membranaceus） and high dosage group （treated with 20 g/kg Astragalus membranaceus）. The model of hemorrhagic shock for 60 min and reperfusion for 90 min was established. Therapeutic solution （3 mL） was administrated before reperfusion. At the end of the study, the observed intestinal pathology was analyzed. The blood concentrations of lactic acid （LD）, nitric oxide （NO）, endothelin-1 （ET-1）, malondialdehyde （MDA） and the activity of superoxide dismutase （SOD）, glutathione peroxidase （GSH-PX） in intestinal mucosa were determined. RESULTS： The intestinal mucosa pathology showed severe damage in model group and low dosage group, slight damage in high dosage group and no obvious damage in normal group. The Chiu＇s score in low dose group and high dose group was significantly lower than that in model group. The content of MDA in model group was higher than that in low and high dose groups, while that in high dose group was almost the same as in normal group. The activity of SOD and GSH-PX was the lowest in model group and significantly higher in high dose group than in normal and low dose groups. The concentrations of LD and ET-1 in model group were the highest. The concentrations of NO in model group and low dose group were significantly lower than those in high dose group and normal group. CONCLUSION： High dose Astraga/us membranaeus has much better protective effect on hemorrhagic shockreperfusion injury of intestinal mucosa than low dose Astragalus membranaceus. The mechanism may be that Astragalus membranaceus can improve antioxidative effect and regulate NO/ET level during hemorrhagic reperfusion.

Gastric mucosal injury due to hemorrhagic reperfusion and efficacy of Salvia miltiorrhizae extract F and cimetidine

AIM: To observe the gastric mucosal injury caused by hemorrhagic shock and reperfusion and to compare the effect between Salvia miltiorrhizae extract F (SEF) and cimetidine (CI) on it. METHODS: A model of hemorrhage/reperfusion injury was produced by Itoh method. Wistar rats were randomly divided into three groups: 0.9% sodium chloride treatment group (NS group), SEF treatment group (SEF group), and CI treatment group (CI group). Saline, SEF and CI were injected respectively. The index of gastric mucosal lesions (IGML) was expressed as the percentage of lesion area in the gastric mucosa. The degree of gastric mucosal lesions was categorized into grades 0, 1, 2, 3. Atom absorption method was used to measure the intracellular calcium content. Radioimmunoassay was used to measure the concentrations of prostaglandins. RESULTS: IGML (%) and grade 3 (%) were 23.18±6.82, 58.44±9.07 in NS group, 4.42±1.39, 20.32±6.95 in SEF group and 3.74±1.56, 23.12±5.09 in CI group, and the above parameters in SEF group and CI group decreased significantly (IGML: SEF vs NS, t=6.712, P=0.000<0.01; CI vs NS, t=6.943, P=0.000<0.01; grade 3: SEF vs HS, t=8.386, P=0.000; CI vs HS, t=8.411, P= 0.000), but the grade 0 and grade 1 damage in SEF group (22.05±5.96, 34.12±8.12) and CI group (18.54±4.82, 30.15±7.12) were markedly higher than those in NS group (3.01±1.01, 8.35±1.95; grade 0: SEF vs HS, t=8.434, P=0.000<0.01; CI vs NS, t=7.950, P=0.000<0.01; grade 1: SEF vs NS, t =8.422, P=0.000<0.01; CI vs NS, t=8.448, P=0.000<0.01). The intracellular calcium content (μg/mg) in SEF group (0.104±0.015) and CI group (0.102±0.010) was markedly lower than that in NS group (0.131±0.019, SEF vs NS, t=2.463, P=0.038<0.05; CI vs HS, t=3.056, P=0.017<0.05). The levels (pg/mg) of PGE_2, 6-keto-PGF_(1α) and 6-keto-PGF_(1α)/TXB_2 were 540±183, 714±124,17.38±5.93 in NS group and 581±168, 737±102, 19.04±8.03 in CI group, 760±192,1 248±158, 33.42±9.24 in SEF group, and the above parameters in SEF group markedly raised (PGE_2: SEF vs NS, t=2.282, P=0.046<0.05; SEF vs CI, t=2.265, P=0.047<0.05; 6-keto-PGF_(1α): SEF vs NS, t=6.583, P=0.000<0.000; SEF vs CI, t=6.708, P=0.000<0.01; 6-keto-PGF_(1α)/TXB_2: SEF vs NS, t=3.963, P=0.003<0.001; SEF vs Cl, t=3.243, P=0.009<0.01), whereas TXB_2 level in SEF group (45.37±7.54) was obviously lower than that in NS group (58.28±6.74, t=3.086, P=0.014<0.05) and CI group (54.32±6.89, t=2.265, P=0.047<0.05). No significant difference was shown between NS group and CI group (PGE_2: t=0.414, P=0.688>0.05; 6-keto-PGF_(1α): t=0.310, P=0.763>0.05; TXB_2: t=1.099, P=0.298>0.05; 6-keto-PGF_(1α)/TXB_2: t=0.372, P=0.718>0.05). CONCLUSION: Both SEF and CI could inhibit reperfusioninduced injury in gastric mucosa, but with different mechanisms. SEF could not only enhance the protective effect of gastric mucosa, but also abate the injury factors, while CI can only abate the injury factors.

Effects of extract F of red-rooted Salvia on mucosal lesions of gastric corpus and antrum induced by hemorrhagic shock-reperfusion in rats

AIM: To compare the effects of extract F of red-rooted Salvia (EFRRS) on mucosal lesions of gastric corpus and antrum induced by hemorrhagic shock and reperfusion in rats. METHODS: The rats were subject to hemorrhagic shock and followed by reperfusion, and were divided randomly into two groups. Group 1 received saline, and group 2 received EFRRS intravenously. The index of gastric mucosal lesions (IGML) was expressed as the percentage of lesional area in the corpus or antrum. The degree of gastric mucosal lesions (DGML) was catalogued grade 0,1,2 and 3. The concentrations of prostaglandins (PGs) were measured by radioimmunoassay. The concentration of MDA was measured according to the procedures of Asakawa. The activity of SOD was measured by the biochemical way. The growth rates or inhibitory rates of above-mentioned parameters were calculated. RESULTS: As compared with IGML (%), grade 3 damage (%) and MDA content (nmol/g tissue) of gastric antrum which were respectively 7.96 +/- 0.59, 34.86 +/- 4.96 and 156.98 +/- 16.12, those of gastric corpus which were respectively 23.18 +/- 6.82, 58.44 +/- 9.07 and 230.56 +/- 19.37 increased markedly (P 【0.01), whereas the grade 0 damage, grade 1 damage, the concentrations of PGE(2) and PGI(2)(pg/mg tissue), the ratio of PGI(2)/TXA(2) and the activity of SOD (U/g tissue) of corpus which were respectively 3.01 +/- 1.01, 8.35 +/- 1.95, 540.48 +/- 182.78, 714.38 +/- 123.74, 17.38 +/- 5.93 and 134.29 +/- 13.35 were markedly lower than those of antrum which were respectively 13.92 +/- 2.25, 26.78 +/- 6.06, 2218.56 +/- 433.12, 2531.76 +/- 492.35, 43.46 +/- 8.51 and 187.45 +/- 17.67 (P【0.01) after hemorrhagic shock and reperfusion.After intravenous EFRRS, the growth rates (%) of grade 0 damage, grade 1 damage, the concentrations of PGE(2) and PGI(2), the ratio of PGI(2)/TXA(2) and the activity of SOD of corpus which were respectively 632.56, 308.62, 40.75, 74.75, 92.29 and 122.25 were higher than those in antrum which were respectively 104.89, 58.40, 11.12, 56.58, 30.65 and 82.64, whereas the inhibitory rates (%) of IGML, grade 3 damage and MDA content of gastric corpus were 82.93, 65.32 and 59.09, being higher than those of gastric antrum which were 76.64, 53.18 and 42.37. CONCLUSION: After hemorrhagic shock reperfusion, the gastric mucosal lesions in the corpus were more severe than those in the antrum, which were related not only to the different distribution of endogenous PGs in the mucosa, but also to the different ability of anti-oxidation of the mucosa. The protective effect of EFRRS on the gastric mucosa in the corpus was more evident than that in the antrum, which was related to higher growth degree of PGs contents and anti-oxitative ability in gastric corpus after administration of EFRRS.

Influence of Tanshinone lla on heat shock protein 70,Bcl-2 and Bax expression in rats with spinal ischemia/reperfusion injury

Tanshinone lla is an effective monomer component of Danshen, which is a traditional Chinese medicine for activating blood circulation to dissipate blood stasis. Tanshinone Ila can effectively improve brain tissue ischemia/hypoxia injury. The present study established a rat model of spinal cord ischemia/reperfusion injury and intraperitoneally injected Tanshinone lla, 0.5 hour prior to model establishment. Results showed that Tanshinone Ila promoted heat shock protein 70 and Bcl-2 protein expression, but inhibited Bax protein expression in the injured spinal cord after ischemia/reperfusion injury. Furthermore, Nissl staining indicated a reduction in nerve cell apoptosis and fewer pathological lesions in the presence of Tanshinone Ila, compared with positive control Danshen injection.

Mesenteric lymph reperfusion may exacerbate brain injury in a rat model of superior mesenteric artery occlusion shock

BACKGROUND：The intestinal lymphatic pathway and intestinal ischemia/reperfusion are mainly involved in mesenteric lymph duct ligation or drainage; moreover,intervention by reducing the lymph liquid reflux might relieve lung and other organ dysfunction induced by intestinal ischemia/reperfusion; however,research addressing mesenteric lymph reperfusion （MLR） and brain injury has not yet to be reported.OBJECTIVE：To observe the effect of MLR on brain tissue in a rat model of superior mesenteric artery occlusion （SMAO） shock,and to explore the molecular mechanism of MLR.DESIGN,TIME AND SETTING：A randomized,controlled,animal experiment at a neuro-pathophysiology level was performed at the Institute of Microcirculation,Hebei North University; Department of Pathophysiology,Basic Medical College; Department of Pathology,the First Hospital of Hebei North University between December 2007 and March 2009.MATERIALS：Adenosine triphosphate （ATP） standard was provided by the National Institute for the Control of Pharmaceutical and Biological Products; lactic acid （LA）,superoxide dismutase （SOD）,malonaldehyde （MDA）,nitrogen monoxidum （NO）,nitric oxide synthase （NOS）,myeloperoxidase （MPO） and ATPase assay kits were provided by Nanjing Jiancheng Bioengineering Institute,China.METHODS：A total of 24 male Wistar rats were randomly divided into four groups.In the sham-surgery group （n = 6）,both the mesenteric lymph duct and the superior mesenteric artery were not blocked; in the MLR group （n = 6）,the mesenteric lymph duct was occluded for 1 hour followed by 2-hour reperfusion; in the SMAO group （n = 6）,the superior mesenteric artery was occluded for 1 hour followed by 2-hour reperfusion; in the MLR ＋ SMAO group （n = 6）,both the mesenteric lymph duct and superior mesenteric artery were occluded for 1 hour followed by 2-hour reperfusion.MAIN OUTCOME MEASURES：Mean arterial blood pressure prior to and following ischemia/reperfusion; brain tissue morphology levels of LA,MDA,SOD,NO,NOS,MPO,ATPase and ATP following reperfusion.RESULTS：MLR did not cause changes in mean arterial blood pressure,brain tissue morphology,LA,MDA,NO,ATP,SOD,NOS,MPO and ATPase.However,SMAO caused a rapid decrease and gradual increase of mean arterial blood pressure.Neuronal necrosis,degeneration and swelling were observed in brain tissue.Contents of MDA,NO,LA and ATP as well as activities of NOS and MPO were significantly increased （P〈 0.05）,but activities of SOD and Na＋-K＋-ATPase were significantly decreased （P 〈 0.05）.MLR aggravated neuronal damage in a rat model of SMAO shock.Following MLR,mean arterial blood pressure was significantly decreased （P 〈 0.05）,contents of MDA and NO as well as activities of NOS and MPO were significantly increased （P 〈0.05）,but activities of Ca2＋-ATPase,Mg2＋-ATPase and Ca2＋-Mg2＋-ATPase as well as ATP content were significantly decreased （P〈 0.05）.CONCLUSION：MLR aggravates brain injury in a rat model of SMAO shock,which correlates with oxygen-derived free radical injury,NO synthesis and release,sequestration of neutrophilic granulocytes,decreasing activity of cell membrane pumps and energy metabolism dysfunction.Pathogenesis of the intestinal lymphatic pathway should be thoroughly investigated to prevent ischemia/reperfusion injury.

Heat shock pretreatment improves stem cell repair following ischemia-reperfusion injury via autophagy

AIM: To investigate whether heat shock pretreatment(HSP) improves mesenchymal stem cell(MSC) repair via autophagy following hepatic ischemia-reperfusion injury(HIRI).METHODS: Apoptosis of MSCs was induced by 250 m M hydrogen peroxide(H2O2) for 6 h. HSP was carried out using a 42 ℃ water bath for 1, 2 or 3 h. Apoptosis of MSCs was analyzed by flow cytometry, and Western blot was used to detect Bcl-2, Bax and cytochrome C expression. Autophagy of MSCs was analyzed by flow cytometry and transmission electron microscopy, and the expression of beclin Ⅰ?and LC3-Ⅱ was detected by Western blot. MSCs were labeled in vivo with the fluorescent dye, CM-Dil, and subsequently transplanted into the portal veins of rats that had undergone HIRI. Liver levels of proliferating cell nuclear antigen(PCNA) were quantified by fluorescent microscopy. Serum aminotransferase activity and the extent of HIRI were also assessed at each time point.RESULTS: HSP for 2 h reduced apoptosis of MSCs induced by H2O2 as seen by a decrease in apoptotic rate, a decrease in Bax and cytochrome C expression and an increase in Bcl-2 expression(P < 0.001). In addition, HSP for 2 h induced autophagy of MSCs exposed to H2O2 as shown by an increase in acidic vesicular organelle-positive cells, beclin 1 and LC3-Ⅱ expression, and autophagosome formation(P < 0.05). Treatment with 3-methyladenine attenuated HSPinduced autophagy and abolished the protective effects of HSP on the apoptosis of MSCs. Rapamycin failed to have additional effects on either autophagy or apoptosis compared with HSP alone. The phosphorylation of p38 MAPK was significantly elevated and the phosphorylation of m TOR was downregulated in heat shock pretreated MSCs. Treatment with the p38 MAPK inhibitor, SB203580, reduced HSP-induced autophagy in MSCs. In vivo studies showed that the transplantation of HSP-MSCs resulted in lower serum aminotransferase levels, lower Suzuki scores, improved histopathology and an increase in PCNA-positive cells(P < 0.05).CONCLUSION: HSP effectively induces autophagy following exposure to H2O2 via the p38MAPK/m TOR pathway, which leads to enhanced MSC survival and improved MSC repair following HIRI in rats.

Effect of abdominal trauma on hemorrhagic shock-induced acute lung injury in rats

TO evaluate the effects of abdominal trauma on hemorrhagic shock-induced acute lung injury in rats. METHODS： Five groups were allocated （n = 8） in the study. Group Ⅰ was taken as the control group, group Ⅱ as the hemorrhagic shock group, group Ⅲ as hemorrhagic shock ＋ laparotomy, group Ⅳ as hemorrhagic shock ＋ splenectomy and group V as splenectomy ＋ omentectomy ＋ hemorrhagic shock group. Hemorrhagic shock was induced by drawing blood and reducing mean arterial pressure （MAP） to 40 mmHg within 10 min. After a hypotensive period of 1 h, animals were resuscitated. Bronchoalveolar lavage （BAL） was performed to recover cells from the alveolar space with 40 mL of BAL fluid after resuscitation malondialdehyde （MDA） and L-γ-glutamyl-L-cysteinylglycine （GSH） levels were measured in serum, erythrocytes and lung tissue. RESULTS： Serum, erythrocyte, lung tissue MDA and GSH levels were significantly increased in hemorrhagic shock groups Ⅱ-Ⅴ （P 〈 0.05）. Lymphocyte, neutrophil and alveolar macrophage counts in BAL fluid indicated a significant difference between control and shock groups （P 〈 0.05）. CONCLUSION： The degree of trauma increases hemorrhagic shock-induced acute lung injury.

Can albumin administration relieve lung injury in trauma/hemorrhagic shock?

AIM: To study the effect of albumin administration on lung injury in trauma/hemorrhagic shock (T/HS). METHODS: Sixty experimental animals were randomly divided into three groups: rats undergoing laparotomy without shock (T/SS); rats with T/HS and resuscitation with blood plus twice the volume of shed blood as Ringer’s lactate (RL), and rats with T/HS and resuscitation with blood plus additional 3 mL of 50 g/L human albumin. Expression of polymorphonuclear neutrophil (PMN) CD11b/CD18, intercellular adhesion molecule-1 (ICAM-1) of jugular vein blood and the severity of lung injuries [determined mainly by measuring activity of lung tissue myeloperoxidase (MPO) and lung injury score (LIS)] were measured after a 3-h recovery period. RESULTS: All three groups showed a significant difference in the expressions of CD11b/CD18, ICAM-1, and severity of lung injury. The expressions of CD11b/ CD18 in T/SS group, T/HS + RL group, T/HS + albumin group were 17.76% ± 2.11%, 31.25% ± 3.48%, 20.36% ± 3.21%, respectively (F = 6.25, P < 0.05). The expressions of ICAM-1 (U/mL) in T/SS group, T/ HS + RL group, T/HS + albumin group were 258.76 ± 98.23, 356.23 ± 65.6, 301.01 ± 63.21, respectively (F = 5.86, P < 0.05). The expressions of MPO (U/g) in T/SS group, T/HS + RL group, T/HS + albumin group were 2.53 ± 0.11, 4.63 ± 1.31, 4.26 ± 1.12, respectively (F = 6.26, P < 0.05). Moreover, LIS in T/HS + RL group, T/HS + albumin group was 2.62 ± 0.23, 1.25 ± 0.24, respectively. The expressions of CD11b/CD18, ICAM-1 and MPO in T/HS + RL group were significantly increased compared to T/SS group (P = 0.025, P = 0.036, P = 0.028,respectively). However, administration of 3 mL of 50 g/L albumin significantly down-regulated the expressions of CD11b/CD18, ICAM-1 and lung injury index (MPO and LIS) when compared with the T/HS + RL rats (P = 0.035, P = 0.046, P = 0.038, P = 0.012, respectively). CONCLUSION: The infusion of albumin during resuscitation period can protect lung from injury and decrease the expressions of CD11b/CD18, ICAM-1 in T/ HS rats.

Effects of GLP on Intestinal Mucosal Injury and the Change of TNF-α Content in Hemorrhagic Shock Rabbits

Objective To observe the intestinal mucosal injury and the change of TNF-αcontent in rabbits with hemorrhagic shock/reperfusion(HS-R)and the effects of ganoderma Lcidum polysaccharide(GLP)on them.Methods 30rabbits were made into hemorrhagic shock,then reperfused with different liquids.These rabbits were divided by random number table into three groups:sham operation group(Sham group),reperfusion with normal saline group(NS group),reperfusion with 1%GLP group(LS group).Bacterial translocation of blood and TNF-αcontent in serum were respectively observed at the time before shock,40 min after shock,40 min and 90 min after.TNF-αcontent in intestinal mucosa and the degree of intestinal mucosal injury were examined at 90 min post-resuscitation.Results 1 With the extension of reperfusion time,the positive rate of blood bacteria increased gradually in NS group,which was significantly higher than that of Sham group and LS group(P<0.05),meanwhile the degree of intestinal mucosal injury in NS group was more severe than that of Sham group and LS group too(P<0.05).2TNF-αcontent in serum of NS group and LS group were increased obviously compared with that before shock and in Sham group(P<0.05).TNF-αcontent in serum was further increased after reperfusion with NS,which was distinctly higher than that in LS group.TNF-αcontent in intestinal mucosa of NS group was significantly higher than that in LS group and Sham group too(P<0.05).Conclusion GLP can protect intestinal mucosa against HS-R injury,and its effects may relate with the change of TNF-αin hemorrhagic shock rabbits.

Stress protein expression in early phase spinal cord ischemia/reperfusion injury

Spinal cord ischemia/reperfusion injury is a stress injury to the spinal cord. Our previous studies using differential proteomics identified 21 differentially expressed proteins （n 〉 2） in rabbits with spinal cord ischemia/reperfusion injury. Of these proteins, stress-related proteins included protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70. In this study, we established New Zealand rabbit models of spinal cord ischemia/reperfusion injury by abdominal aorta occlusion. Results demonstrated that hind limb function initially improved after spinal cord ischemia/reperfusion injury, but then deteriorated. The pathological morphology of the spinal cord became aggravated, but lessened 24 hours after reperfusion. However, the numbers of motor neurons and interneurons in the spinal cord gradually decreased. The expression of protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70 was induced by ischemia/reperfusion injury. The expression of these proteins increased within 12 hours after reperfusion, and then decreased, reached a minimum at 24 hours, but subsequently increased again to similar levels seen at 6-12 hours, showing a characterization of induction-inhibition-induc- tion. These three proteins were expressed only in cytoplasm but not in the nuclei. Moreover, the expression was higher in interneurons than in motor neurons, and the survival rate of interneurons was greater than that of motor neurons. It is assumed that the expression of stress-related proteins exhibited a protective effect on neurons.

Exacerbated VEGF up-regulation accompanies diabetes-aggravated hemorrhage in mice after experimental cerebral ischemia and delayed reperfusion

Reperfusion therapy is the preferred treatment for ischemic stroke,but is hindered by its short treatment window,especially in patients with diabetes whose reperfusion after prolonged ischemia is often accompanied by exacerbated hemorrhage.The mechanisms underlying exacerbated hemorrhage are not fully understood.This study aimed to identify this mechanism by inducing prolonged 2-hour transient intraluminal middle cerebral artery occlusion in diabetic Ins2Akita/+mice to mimic patients with diabetes undergoing delayed mechanical thrombectomy.The results showed that at as early as 2 hours after reperfusion,Ins2Akita/+mice exhibited rapid development of neurological deficits,increased infarct and hemorrhagic transformation,together with exacerbated down-regulation of tight-junction protein ZO-1 and upregulation of blood-brain barrier-disrupting matrix metallopeptidase 2 and matrix metallopeptidase 9 when compared with normoglycemic Ins2+/+mice.This indicated that diabetes led to the rapid compromise of vessel integrity immediately after reperfusion,and consequently earlier death and further aggravation of hemorrhagic transformation 22 hours after reperfusion.This observation was associated with earlier and stronger up-regulation of pro-angiogenic vascular endothelial growth factor(VEGF)and its downstream phospho-Erk1/2 at 2 hours after reperfusion,which was suggestive of premature angiogenesis induced by early VEGF up-regulation,resulting in rapid vessel disintegration in diabetic stroke.Endoplasmic reticulum stress-related pro-apoptotic C/EBP homologous protein was overexpressed in challenged Ins2Akita/+mice,which suggests that the exacerbated VEGF up-regulation may be caused by overwhelming endoplasmic reticulum stress under diabetic conditions.In conclusion,the results mimicked complications in patients with diabetes undergoing delayed mechanical thrombectomy,and diabetes-induced accelerated VEGF up-regulation is likely to underlie exacerbated hemorrhagic transformation.Thus,suppression of the VEGF pathway could be a potential approach to allow reperfusion therapy in patients with diabetic stroke beyond the current treatment window.Experiments were approved by the Committee on the Use of Live Animals in Teaching and Research of the University of Hong Kong[CULATR 3834-15(approval date January 5,2016);3977-16(approval date April 13,2016);and 4666-18(approval date March 29,2018)].

Heat shock protein 72 normothermic ischemia,and the impact of congested portal blood reperfusion on rat liver

INTRODUCTIONFrom the technical aspect of liver surgery ,control of bleeding during hepatic parenchymal resection is one of the most important procedures in hepatectomy .Pringle,s maneuver ,a temporary cross-clamping of the hepatoduodnal ligament ,has often been used for this purpose[1],This is the simplest and userul technique to reduce intraoperative blood loss .

Effect of methylprednisolone on reperfusion injury in severe uncontrolled hemorrhagic shock

Objective: To study the effect of methylprednisolone (MP) on reperfusion injury in severe uncontrolled hemorrhagic shock and explore the possible mechanism involved. Methods: Twelve dogs were randomly divided into two groups, control group (Group I, n=6) and MP group (Group II, n=6). The animals were bled continuously from a femoral artery catheter to produce uncontrolled hemorrhagic shock models. Resuscitation with lactated Ringer’s (LR) solution was initiated when mean arterial pressure (MAP) decreased to 20 mm Hg, and MAP was maintained at 30-40 mm Hg. MP (4 mg/kg) was injected intravenously in Group II when resuscitation began. While in Group I, normal saline (NS) was injected instead. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured before exsanguination (T 1), when MAP decreased to 20 mm Hg (T 2), 60 min (T 3) and 120 min (T 4) after resuscitation. Heart rate, MAP and cardiac output (CO) levels were recorded concomitantly. Results: Infusion volume and hemorrhage volume shed from the superior mesenteric artery in Group I were higher than those in Group II (P< 0.01 and P< 0.05). After reperfusion, blood SOD levels decreased progressively and MDA levels increased rapidly in Group I. In Group II, blood SOD levels at T 3 and T 4 decreased as compared with that at T 1 but a stepwise increase was present. At T 4, blood SOD level was significantly higher in Group II than in Group I (P< 0.01). At T 3 and T 4, MDA levels were markedly lower in Group II than in Group I. During reperfusion, MAP was more steady in Group II than in Group I and survival rate after 120 min (at T 4) was higher in Group II than in Group I (P< 0.05). Conclusions: MP has a protective effect on severe uncontrolled hemorrhagic shock and subsequent reperfusion injury. The mechanism mainly involves the anti-lipid peroxidation activity of MP.

Effect of Astragalus membranaceus injection on the activity of the intestinal mucosal mast cells after hemorrhagic shock-reperfusion in rats

Background The mechanism of mucosal damage induced by ischemia-reperfusion （IR） after hemorrhagic shock is complex; mast cells （MC） degranulation is associated with the mucosal damage. Astragalus membranaceus can protect intestinal mucosa against intestinal oxidative damage after hemorrhagic shock, and some antioxidant agents could prevent MC against degranulation. This study aimed to observe the effects of astragalus membranaceus injection on the activity of intestinal mucosal mast cells （IMMC） after hemorrhage shock-reperfusion in rats Methods Thirty-two Wistar rats were randomly divided into the normal group, model group, low dosage group, （treated with Astragalus membranacaus injection, 10 g crude medication/kg） and high dosage group （treated with Astragalus membranacaus injection, 20 g crude medication/kg）. The rat model of hemorrhagic shock-reperfusion was induced by hemorrhage for 60 minutes followed by 90 minutes of reperfusion. The animals were administrated with 3 ml of the test drug solution before reperfusion. At the end of study, intestinal pathology, ultrastructure of IMMC, and expression of tryptase were assayed. The levels of malondisldehyde （MDA）, TNF-α, histamine, and superoxide dismutase （SOD） activity in intestine were detected, and the number of IMMC was counted. Results The Chiu＇s score of the rats in the model group was higher than in other groups （P〈0.01）. The Chiu＇s score in the high dosage group was higher than that in the low dosage group （P〈0.05）. Hemorrhage-reperfusion induced IMMC degranulation： Astragalus membranaceus injection attenuated this degranulation. Expression of tryptase and the number of IMMC in the model group increased compared with the other groups （P〈0.01） and was significantly reduced by the treatments of Astragalus membranaceus injection at both doses. There was no significant difference between the two treatment groups （P〉0.05）. MDA content and concentration of TNF-α in the model group were higher than that in the other three groups （P〈0.05）, and the concentration of TNF-α in the low dosage group was higher than that in the high dosage group （P〈0.05）. SOD activity and the concentration of histamine in the model group were lower than the other three groups （P〈0.05）. There was a negative correlation between the Chiu＇s score and the concentration of histamine and a positive correlation between the Chiu＇s score and the concentration of TNF-α and between the SOD activity and the concentration of histamine in the four groups （P〈0.05）. Conclusion Astragalus membranaceus injection may reduce the damage to small intestine mucosa by inhibiting the activated IMMC after hemorrhagic shock.

皮瓣缺血再灌注损伤的发病机制及治疗进展

背景:皮瓣移植技术是治疗严重组织缺损的常用外科手术方式,但术后因缺血再灌注损伤容易引发皮瓣坏死,因此提高移植皮瓣的存活率仍是目前重要的研究课题。目的:综述皮瓣缺血再灌注损伤的发病机制及最新治疗进展。方法:检索CNKI、万方和PubMed数据库中2014-2024年发表的相关文献,中文检索词为“皮瓣,缺血再灌注损伤,炎症反应,氧化应激反应,Ca^(2+)超载,细胞凋亡,间充质干细胞,富血小板血浆,信号通路,冲击波,预处理”,英文检索词为“flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca^(2+)overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,Shock wave,Pretreatment”。通过阅读文章剔除研究内容与文章主题关系不大、质量较差及内容陈旧文献,最终纳入77篇文献进行归纳总结。结果与结论:皮瓣缺血再灌注损伤损伤可能与炎症反应、氧化应激反应、Ca^(2+)超载、细胞凋亡等病理因素有关,引起皮瓣血管内皮细胞凋亡、血管损伤和微循环障碍,最终导致皮瓣坏死。研究发现,间充质干细胞移植、富血小板血浆、信号通路调节剂、冲击波及预处理等治疗方法均可以从不同方向在不同程度上缓解皮瓣缺血再灌注损伤,降低移植皮瓣的坏死率和坏死面积。关于皮瓣缺血再灌注损伤的治疗方法虽然很多,然而临床还未形成统一有效的治疗方法,各种治疗方法的优缺点也未进行对比研究,并且大部分研究都停留在动物实验阶段,临床观察研究甚少,因此未来还需要进行大量研究,逐步由动物实验向临床迈进,以便更好地为临床服务。

Vitamin C Attenuates Hemorrhagic Shock-induced Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Nonintegrin Expression in Tubular Epithelial Cells and Renal Injury in Rats

Background： The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin （DC-SIGN） in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases, but whether it takes place in renal tissues during hemorrhagic shock （HS） is unknown. The present study airned to investigate this phenomenon and the inhibitory effect of Vitamin C （VitC）. Methods： A Sprague Dawley rat HS model was established in vivo in this study. The expression level and location of DC-SIGN were observed in kidneys. Also, the degree of histological damage, the concentrations of tumor necrosis factor-or and interleukin-6 in the renal tissues, and the serum concentration of blood urea nitrogen and creatinine at different times （2-24 h） alter HS （six rats in each group）, with or without VitC treatment belbre resuscitation, were evaluated. Results： HS induced DC-SIGN expression in rat tubular epithelial cells. The proinflarnmatory cytokine concentration, histological damage scores, and functional injury of kidneys had increased. All these phenornena induced by HS were relieved when the rats were treated with VitC before resuscitation. Conclusions： The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN, and the levels of proinflarnmatory cytokines in the kidney tissues improved correspondingly. The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney.

S100B protein in serum is elevated after global cerebral ischemic injury

BACKGROUND:S100B protein in patients with cardiac arrest,hemorrhagic shock and other causes of global cerebral ischemic injury will be dramatically increased.Ischemic brain injury may elevate the level of serum S100 B protein and the severity of brain damage.METHODS:This article is a critical and descriptive review on S100 B protein in serum after ischemic brain injury.We searched Pubmed database with key words or terms such as "S100B protein", "cardiac arrest", "hemorrhagic shock" and "ischemia reperfusion injury" appeared in the last five years.RESULTS:S100B protein in patients with cardiac arrest,hemorrhagic shock and other causes of ischemic brain injury will be dramatically increased.Ischemic brain injury elevated the level of serum S100 B protein,and the severity of brain damage.CONCLUSION:The level of S100 B protein in serum is elevated after ischemic brain injury,but its mechanism is unclear.

Mechanism of macrophage injury following traumatic hemorrhagic shock: through PTX-sensitive G-protein-mediated signal transduction pathway

Objective: To study the mechanism of macrophage injury after trauma-hemorrhagic shock. Methods: Wistar male rats underwent trauma (closed bone fracture) and hemorrhage (mean arterial blood pressure of 35 mm Hg±5 mm Hg for 60 minutes, following fluid resuscitation). Rats without trauma, hemorrhage or fluid resuscitation served as controls. Peritoneal macrophages were harvested at 6 hours and 1, 2, 3, 7 days after traumatic hemorrhagic shock to determine the effects of pertussis toxin (PTX, as a specific inhibitor to Giα) and cholera toxin (CTX, as a stimulant to Gsα) on macrophage-Ia expression and TNF-α production and levels of Giα and Gsα. Results: The macrophages from the injured rats revealed a significant decrease of Ia positive number and TNF-α release in response to LPS. With pretreatment with PTX 10-100 ng/ml Ia positive cells and LPS-induced TNFα production in both control and impaired macrophages populations were dose-dependently increased. Both macrophages populations were not responding to CTX treatment (10-100 ng/ml). Western blot analyses showed that the levels of Giα protein expression increased as much as 116.5%- 148.8% of the control level from 6 hours through 7 days after traumatic hemorrhage. The levels of Gsα protein expression were reduced at 6 hours and decreased to the lowest degree; 36% of the control at day 1, began to return at day 2 and returned to the normal level at day 7, following traumatic hemorrhagic shock.Conclusions: PTX-sensitive G-protein may participate in the modulation of macrophage-Ia expression and TNF-α release following traumatic hemorrhagic shock. Analyses of the alteration of Giα and Gsα protein expressions further supports the concept that G-protein is involved in trauma-induced macrophage signal transduction pathways.

失血性休克后肾脏保护的研究进展

失血性抗休克是一种由于创伤等原因引起的临床常见的急危重症。尤其是肾脏在缺血缺氧后引起的局部组织灌注不足和细胞缺氧,极易导致急性肾损伤。临床上在不断探寻患者失血性休克后更安全、实用和有效的复苏方法,如从晶胶液体到高渗液体、从常压复苏到低压复苏、从纠正血压到恢复组织细胞的氧供、从维持血流动力学稳定到抑制细胞凋亡、从血管活性药到中药再到酶抑制剂的应用等等,以达到更好地保护肾脏的目的。本文就近年来关于失血性休克患者肾脏的保护研究进展进行综述。