Hemodynamic changes of abdominal organs in the early stage of septic mice induced by cecal ligation and puncture

AIM: To characterize the hemoperfusion of abdominal organs in the early stage of sepsis in mice. METHODS: Health male Kunming mice were used in the study (n=100). The techniques of 2D, M-mode and pulse-wave Doppler were applied to evaluate the systolic functions of the heart and the blood flow of abdominal aorta, right renal artery and portal vein before cecal ligation and puncture (CLP) as the baseline and at the time points of 12 h, 24 h, 36 h, 48 h and 60 h after CLP. The mice survived for 7 d were considered as survivals. All data were compared with the baseline values.RESULTS: The cardiac output of the CLP mice remained in normal or hyperdynamic levels in the early stage of sepsis. Compensatory responses of systolic functions were observed. The levels of blood flow in abdominal aorta were increased first and then decreased. Resistent index (RI) and pulsatility index (PI) of abdominal aorta began to increase at the time point of 24 h. Blood flow of right renal artery showed a significant decline from the beginning to the end of our observation. No significant difference of the right arteriorenal RI and PI was observed. Portal venous flow increased significantly at 12 h, and decreased at 24 h after CLP. Congestion index of the portal vein was distinctly increased from 12 h to the end of the observation. CONCLUSION: The hemodynamics of abdominal organs in early stage of septic mice shows specific changes, indicating an important role in evaluating the mechanism of sepsis.     

Dynamic expression of CD30 on peripheral blood lymphocytes in mice after a cecal ligation and puncture

AIM: To investigate the details of Th2 cell differentiation in septic mice. METHODS: Experimental septic mice were induced by cecal ligation and puncture (CLP). The exression of CD30 on CD4⁺T cells at different time after CLP were estimated by flow cytometry following three-color immunofluorescent staining.RESULTS: CD30 expression on CD4⁺T cell was different at each time point. The highest expression was showed at 38 h after CLP and declined later, which matched the changes in mortality of the animals. CONCLUSION: During sepsis, differentiation of Th2 cell changed with the development of sepsis and might be associated with the severity of the disease.     

The protective effect of cistanche deserticola Y.C Ma. on thymocytes in septic rats

AIM: To study the protective effect of cistanche deserticola Y. C Ma. on thymocytes in septic rats. METHODS: Cecum ligation perforation (CLP) was used to induce sepsis. Treatment group was treated with cistanche deserticola Y. C Ma. （1.25 g·kg-1·d-1， ig） for 14 days before CLP. Animals were killed 12 h or 24 h after CLP and thmocytes were collected. The ratio of thmocyte apoptosis and mitochondrial membrane potential were determined by the flow cytometry. The ATP activity was detected by spectrophotography. RESULTS: The rate of thmocyte apoptosis significantly increased 12 h after CLP. The ATP activity decreased 24 h after CLP was significant. The extract of desert living cistanche effectively repressed the apoptosis of thymocytes and maintained the mitochondrial membrane potential. CONCLUSIONS: The extract of cistanche deserticola Y. C Ma. protects thymocytes against apoptosis induced by sepsis. Maintaining of mitochondrial membrane potential may be the protective mechanism.     

Effects of berberine and yohimbine on splenocyte apoptosis in septic mice

AIM: To observe the effects of berberine and yohimbine on splenocyte apoptosis in septic mice and underlying mechanisms. METHODS: The mice were subjected to cecal ligature and puncture (CLP). The drugs or vehicle were given intragastrically 2 h after the surgery according to the following 5 groups: sham, CLP, CLP+berberine, CLP+yohimbine, and CLP+berberine+yohimbine. The apoptosis of splenocytes stained by TUNEL was observed under laser scanning confocal microscope 20 h after CLP. The splenic lymphocytes were isolated and observed using flow cytometry. The activities of caspase-3, caspase-8 and caspase-9 in splenic lymphocytes were detected, and the expression of Fas, Bim, Bcl-2 and Bax in the splenocytes was also determined by Western blotting. RESULTS: The TUNEL staining showed that the apoptotic rate of the splenocytes in septic mice 20 h after CLP was significantly higher than that in sham and CLP+yohimbine groups (P＜0.05). Compared with CLP group, the proportion of apoptotic cells was decreased in septic mice in CLP+berberine+yohimbine and CLP+yohimbine groups (P＜0.05). Flow cytometry analysis demonstrated the similar results in the apoptosis of splenocytes and T lymphocytes. However, only yohimbine treatment reduced the apoptosis of B lymphocytes in the spleen of sepsis-challenged mice. Compared with CLP group, caspase-9 activity was significantly reduced in CLP+berberine group (P＜0.05), the activities of caspase-3, caspase-8 and caspase-9 were all statistically reduced (P＜0.05) in CLP+yohimbine group and CLP+yohimbine+berberine group. CLP significantly increased the expression of cytosolic Fas, Bim and mitochondrial Bax in the splenocytes, and decreased Bcl-2 expression compared with sham group. Compared with CLP group, the expression of cytosolic Bim and mitochondrial Bax in CLP+berberine group were reduced (P＜0.05). Fas expression decreased only in CLP+yohimbine group (P＜0.05). Berberine combined with yohimbine reduced the expression of cytosolic Fas, Bim and mitochondrial Bax in the septic mouse splenocytes (P＜0.05).CONCLUSION: Yohimbine reduces sepsis-induced splenic lymphocyte apoptosis in mice by inhibiting Fas expression and in turn blocking both extrinsic and intrinsic apoptosis pathways. Berberine reduces Bim expression and inhibits caspase-9 activation, but not caspase-3 activation and apoptosis in the septic mouse splenocytes. Berberine combined with yohimbine reduces splenocyte apoptosis in the septic mice by inhibiting both extrinsic and intrinsic apoptotic pathways.     

Protective effect of ginkgolide B on CLP-induced septic mice

AIM: To explore the potential immunomodulatory effect and related mechanisms of ginkgolide B (GB), a known potent antagonist of platelet-activating factor receptor, on the pathological process of sepsis. METHODS: The experimental sepsis model was established by a standardized procedure of cecal ligation and puncture (CLP). GB treatment (10 μg/g) was given to the CLP mice 30 min before the surgical operation. The survival rate was observed every day for 3 weeks. The NO content in the serum was measured by Griess assay. The ROS level in the blood was determined by H₂DCFDA labeling and flow cytometry. The inflammatory cytokines in the serum were detected by the methods of cytometric bead array and ELISA. RESULTS: The thymus and spleen of the mice significantly atrophied, and the levels of NO, ROS, TNF-α, IL-1β, IL-6 and IL-10 in the blood were dramatically elevated 24 h after CLP. All the CLP mice died in 5 days. However, treatment with 10 μg/g of GB 30 min before CLP remarkably enhanced the indexes of thymus and spleen, inhibited the storm of inflammatory mediators and cytokines, and improved the survival rate. CONCLUSION: The protective effect of GB on CLP-induced experimental sepsis indicates that GB is a candidate of natural immunomodulator for treating sepsis.     

Assessment of myocardial dysfunction in septic rats with conventional echocardiography and tissue Doppler imaging

AIM To compare various conventional and tissue Doppler echocardiographic indexes to assess their accuracy to detect left ventricular (LV) intrinsic systolic and diastolic dysfunction in septic rats. METHODS Twenty-two SD rats were randomly divided into 2 groups: sham group and sepsis group, with 11 rats in each group. A model of sepsis was established by cecal ligation and puncture (CLP). Serum tumor necrosis factor-α (TNF-α) level, and myocardial intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression were determined by ELISA and Western blot. The LV systolic and diastolic functions were analyzed by isolated heart Langendorff perfusion technique, conventional echocardiography and tissue Doppler imaging. RESULTS Compared with sham group, the serum TNF-α level, and LV ICAM-1 and VCAM-1 expression were increased significantly, while LV ±dp/dt_max, stroke volume and LV end-diastolic volume were markedly decreased at 6 h after CLP. Moreover, compared with sham group, mitral inflow peak E and A wave velocities as well as early-diastolic peak velocities (E' wave) and late-diastolic peak velocities (A' wave) of the mitral annulus were reduced significantly in sepsis group at 6 h after CLP. In contrast, no significant difference in LV ejection fraction and E/E' ratio between sham group and sepsis group was observed. Further investigation revealed that peak E' wave and A' wave velocities were positively correlated with -dp/dt_max (r=0.460 and r=0.520, P<0.05). CONCLUSION At the early stage of sepsis, tissue Doppler echocardiography is a useful technique to assess LV diastolic dysfunction, and peak E' and A' wave velocities may be the sensitive indexes to detect LV intrinsic diastolic dysfunction.     

Berberine inhibits enterocyte apoptosis in septic mice

AIM: To observe the effects of berberine (Ber) on enterocyte apoptosis in septic mice and its possible mechanism. METHODS: Male C57BL/6 mice (8~10 weeks old) were randomly divided into sham group, cecal ligation and puncture (CLP) group, CLP+Ber group and sham+Ber group. The mice in CLP group underwent CLP ope-ration, and the mice in sham groups suffered a similar operation except the ligation and puncture. After the sham or CLP operation, the mice were administered intragastrically with distilled water or berberine (50 mg/kg) within 2 h. After 20 h, the mice were killed with excess pentobarbital sodium and the ileum tissues were removed. The histological changes of the intestine were observed and the enterocyte apoptosis was examined by determining the protein level of cleaved caspase-3. Furthermore, mitochondrial Bax, cytoplasm cytochrome C (Cyt C) and the total proteins of Bcl-2, Fas, FasL and Fas-associated protein with death domain (FADD) were examined by Western blot. The mRNA expression of tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) was measured by real-time PCR. RESULTS: The extensive ileum injuries, including remarkably increased leukocytes and necrosis of intestinal villus were observed 20 h after CLP. In CLP group, the protein levels of cleaved caspase-3, cytoplasm Cyt C, as well as Fas, FasL were significantly increased, but the Bcl-2 level was decreased. Bax translocation into mitochondria was promoted. However, FADD was not changed significantly. The mRNA expression of TH and DBH was also increased sharply in CLP group. On the contrary, treatment with berberine made a considerable alleviating alteration in the ileum of the septic mice.CONCLUSION: Treatment with berberine provides protective effects on intestinal injury in septic mice by reducing enterocyte apoptosis, and its possible mechanism may be involved in the inhibition of the endogenous and exogenous apoptosis pathways.     

Changes of L-arginine,NOS/NO pathway in adventitia of rats with sepsis

AIM: In this study, we aimed to explore the alteration and pathophysiological significance of the L-arginine (L-Arg)/NOS/NO pathway in the adventitia of rats with sepsis. METHODS: Sepsis was induced by cecal ligation and puncture (CLP). Rat cardiac function was determined. NO generation, NOS activity and L-Arg transport were measured. The iNOS mRNA levels was determined by using RT-PCR. RESULTS: Cecal ligation and puncture induced severe sepsis with severe low glucose, high lacticemia and cardiac function inhibition. The iNOS activity was increased by 2.8-fold compared with controls (P<0.01) and the iNOS mRNA level was elevated-6-fold (P<0.01). The NO level in plasma and incubation media (incubation for 40 min) in the sepsis group was increased by 144% and 273% (both P<0.01), respectively. CONCLUSION: The results demonstrated that the L-Arg,NOS/NO pathway was activated in vascular adventitia of rats with sepsis shock. The aortic adventitia L-Arg/NOS/NO pathway might play an important role in the pathogenesis of sepsis and septic shock.     

The disturbance of calcium metabolism of vascular smooth muscle in the late phase of septic shock and the underlying mechanism

AIM: To evaluate the alterations in calcium metabolism of the vascular smooth muscle in the late phase of septic shock and test the hypothesis that nitric oxide might be involved in sepsis-induced vascular hyporeactivity. METHODS: Male Sprague-Dawley rats were subjected to sepsis by cecal ligation and puncture (CLP). 18 hours post CLP, rat aortic rings were employed for measurement of contractile responses by using organ bath technique. RESULTS: In endothelium-denuded aortic rings from CLP rats, concentration-contraction curves to phenylephrine (PE) and KCl were significantly decreased when compared to that from sham control rats. The transient contraction induced by PE in calcium-free Krebs solution and the concentration-dependent contraction to CaCl₂ in KCl-depolarized medium were also markedly reduced. The hyporeactivity was partially reversed by treatment with aminoguanidine, a selective inducible nitric oxide synthase inhibitor. CONCLUSION: An impairment in calcium handling in vascular smooth muscle is involved in the vascular hyporeactivity during the late phase of septic shock, in which an excessive nitric oxide production might be the major mechanism.     

Effect of electro-acupuncture at Zusanli point on tumor necrosis factor-α induced-multiple organ dysfunction in rats with sepsis

AIM: To investigate the effect of electro-acupuncture (EA) at Zusanli (ST36) on proinflammatory factors induced-multiple organ dysfunction in rats with sepsis. METHODS: Sixty four male Wastar rats were used to develop the sepsis model by cecal ligation and puncture (CLP). The animals were randomly divided into 4 groups (n=16 in each group): CLP+EA (CLP/EA), CLP+sham EA (CLP/SEA), vagotomy+ CLP+SEA (VA/CLP/SEA) and vagotomy+CLP+EA (VA/CLP/EA). Zusanli point (ST36) was electroacupunctured with constant voltage (2-100 Hz, 2 mA for 0.5 h) 20 min after CLP surgery. Bilateral cervical vagotomies were performed in rats in VA/CL/SEA and VA/CLP/EA groups. Twelve hours after CLP, animals were sacrificed and liver, kidney and jejunum were harvested for evaluating the contents of tumor necrosis factor-α (TNF-α), myeloperoxidase (MPO) and diamine oxidase (DAO). The rate of water content (WCR) of the organs was determined. At the same time, the plasma levels of alanine aminotransferase (ALT) and creatinine (Cr) in each group were also detected. RESULTS: The levels of ALT and Cr in plasma, as well as TNF-α, MPO and WCR in organ tissues were markedly lower, and the activity of DAO in jejunum tissue was obviously higher than that in CLP/SEA group at 12 h after CLP (all P<0.05). The levels of ALT, Cr, TNF-α, MPO and WCR in VA/CLP/SEA group and VA/CLP/EA group were significantly higher, the activity of DAO was obviously lower than that in CLP/SEA group (all P<0.05). No statistical difference in all above measurements between VA/CLP/EA group and VA/CLP/SEA group was observed (all P>0.05). CONCLUSION: The results indicate that EA at Zusanli point obviously decreases the levels of TNF-α in liver, kidney and jejunum tissues after CLP, and alleviates the tissue edema and dysfunction of those organs. Vagotomy decreases or eliminates the effects of EA, suggesting that activation of cholinergic anti-inflammatory pathway is one of the main mechanisms to induce the effects of EA at ST36 on CLP sepsis.     

Effect of ghrelin on iNOS expression in alveolar macrophages and lung tissues in rats with sepsis-associated lung injury

AIM: To investigate the effect of ghrelin on inducible nitric oxide synthase (iNOS) expression in alveolar macrophages and lung tissues in sepsis-induced acute lung injury (ALI) rats. METHODS: The septic rat model was established by cecal ligation and puncture (CLP). Male SD rats were divided into sham group, CLP group and CLP+ghrelin group. The rats in the former 2 groups were further divided into 3 subgroups, which were 6 h, 12 h and 20 h post-operation groups. Ghrelin was administered by intraperitoneal injection at 3 h and 15 h after operation in ghrelin group. The samples were harvested 20 h after operation. The mRNA expression of iNOS in alveolar macrophages collected from bronchoalveolar lavage was detected by RT-PCR. The protein levels of lung iNOS were measured by Western blotting. The lung pathological examination was performed 20 h after operation. RESULTS: In CLP group, the mRNA expression levels of iNOS in the alveolar macrophages were 1.33±0.05, 1.44±0.08, 1.57±0.11 at 6 h, 12 h and 20 h after CLP, respectively, which were higher than that in sham group, but did not show time correlation. However, it was lower in CLP group than that in CLP+ghrelin group at 20 h after CLP (2.27±0.37, P<0.05). At 20 h after CLP, the protein level of lung iNOS was decreased in CLP+ghrelin group (0.87± 0.03) as compared with CLP group (1.08±0.05). Compared with sham group, the histopathological score was increased in both CLP group and CLP+ghrelin group, but it was lower in CLP+ghrelin group (5.83±0.477) than that in CLP group (7.83±0.75). CONCLUSION: Ghrelin treatment improves the degree of ALI. During 6 h to 20 h after CLP, the mRNA expression of iNOS in alveolar macrophages was elevated, but the difference was not seen as the time went on. Ghrelin up-regulates the mRNA expression of iNOS in alveolar macrophages and inhibits iNOS expression in lungs of septic rats.     

Mechanisms of hepatocytic mitochondria damage following septic shock

AIM: To study mechanism of hepatocytic mitochondria damage following septic shock. METHODS: 30 SD rats were randomly divided into three groups: sham operation group, 12 h cecal ligation and puncture (CLP) group and 16 h CLP group. The model of septic shock was made by cecal ligation and puncture. The liver mitochondria respiratory control rate (RCR), phosphate/oxygen (P/O) and ATPase activities were assayed. RESULTS: In 12 h CLP group mean artery pressure (MAP) [(9.54±1.26)kPa] was significantly lower than sham operation group [(14.58±1.32)kPa,P<0.05]. However, mortality was obviously higher than sham operation group (P<0.05), the liver mitochondria respiratory control rate (1.27±0.25), phosphate/oxygen (1.67±0.34) and Na⁺-K⁺-ATPase (40.80±3.45), Ca²⁺-ATPase (58.00±2.43), Mg²⁺-ATPase (78.30±4.16), Ca²⁺-Mg²⁺-ATPase(2.70±2.25) activities decreased strikingly. The difference between 12 h CLP group and sham operation group was significant (P<0.05), 16 h CLP groups was more lower than 12 h CLP group. As RCR, P/O and ATPase activities were significantly reduced, mortality significantly increased. Futhermore, obvious positive correlation was showed between them (r=0.892,P<0.01;r=0.834,P<0.01). CONCLUSION: Liver mitochondria function of ingestion-oxygen and phosphorus-acidification are decreased and membrane fluxion is weaken. Energy metabolism is blocked and Ca²⁺-Mg²⁺ shows imbalanced. All of them cause hepatocytic mitochondria injury following septic shock.     

Establishment of a mouse model of sepsis associated encephalopathy and preliminary research of cognitive dysfunction in this model

AIM: To establish the mouse model of sepsis-associated encephalopathy (SAE) and the preliminary research of cognitive dysfunction in this model. METHODS: SPF male C57BL/6J mice of 8~10 weeks old were selected. The first part of the experiment divided the mice into 4 groups randomly, namely control group, cecal ligation and puncture (CLP)1 group and CLP2 group (CLP was performed with 7 and 12 syringe needle respectively). The mice in sham operation group were only laparotomy. In the second part of the experiment, the mice were randomly divided into control group, sham operation group and CLP group. The Kaplan-Meier method was used to analyze the postoperative survival rate of the mice in the first part experiment. The neurobehavioral scores were used to evaluate the neurobehavioral changes of the mice. The Morris water maze test and the passive avoidance experiment were used to detect the changes of cognitive memory function in the mice. The pole test and the wire suspension test were used to test the motor coordination of the mice. The serum levels of prostaglandin E2 (PGE₂) were measured by ELISA. RESULTS: In the first part of the experiment, the CLP mice showed obvious symptoms such as lethargy, piloerection, chills and anorexia. The 48 h mortality in CLP1 group and CLP2 group were 20% and 30% respectively. In the 2 parts of the experiments, the neurobehavioral scores of the CLP mice were significantly lower than those in control group and the sham operation group (P<0.01). In CLP mice, the escape latency time of the Morris water maze was significantly prolonged (P<0.01), the target quadrant dwell time and the number of crossing platforms were decreased (P<0.01), the scores in the suspension experiment and the pole test were significantly reduced (P<0.01), the activity of the mice was decreased or even did not enter the darkroom in the step-through test (P<0.05). In the second part of the experiment, the serum level of PGE₂ in the mice after CLP was significantly increased (P<0.01). CONCLUSION: A stable mouse model of sepsis-associated encephalopathy is successfully established by cecal ligation and puncture with 12 syringe needle. The SAE mouse model established by this method is useful for investigating the learning and memory cognitive dysfunction.     

Effects of brain tissue extract of hypoxia-preconditioned mice at different concentrations on tolerance of PC12 cells to hypoxia

AIM: To investigate the effect of brain tissue extract of hypoxia-preconditioned mice (HP extract) on tolerance of PC12 cells to hypoxia. METHODS: The mice model of acute repetitive hypoxia was reproduced and brain tissue extracts were prepared. HP extract was added into the cultures of PC12 cells and the final concentrations of HP extracts were 0.2, 0.8, 3.2, 6.4 or 12.8 g/L (HP group), respectively. Brain tissue extract of normal mice (N extract) at the same five concentrations were used as controls (N group). The PC12 cells were cultured in hypoxia (2% O2). After hypoxia for 24 h, 48 h or 72 h, colorimetric method (A570) of tetrazolium salt MTT (3-［4,5-dimethylthiazol-2-yl］-2,5-diphenyl tetrazolium bromid) staining was adopted to determine the cell viability and lactate dehydrogenase (LDH) release percentage assay was also conducted after 24 h, 48 h or 72 h hypoxia. Besides, apoptotic percentages at early stage (24 h hypoxia) and late stage (72 h hypoxia) were detected respectively by means of annexin V-FITC/PI double-stained flow cytometry and Hoechst 33258 stained fluorescence microscopy. RESULTS: HP extract at the concentrations lower than 6.4 g/L (including 6.4 g/L) showed protective effect on PC12 cells in early stage of hypoxia (24 h). A570 values in HP group were significantly higher than those in N group, but LDH release percentages were significantly lower than those in N group after 24 h hypoxia. With hypoxia prolonging, HP extract at high concentrations gradually lost the protective effect. At the time point of 72 h hypoxia, HP extract at concentrations higher than 6.4 g/L (including 6.4 g/L) had pro-apoptotic effect. At this time point, A570 values of HP groups at these concentrations were significantly lower than those in the corresponding N group, both LDH release percentages and apoptotic percentages were significantly higher than those in the N group. CONCLUSION: The effects of HP extract on tolerance of PC12 cells to hypoxia depend on its concentrations and on the time of treatment.     

Protective effect of A. auricula-judae extracts on liver function in septic rats

AIM: To explore the effects of Auricularia (A.) auricula-judae extracts on the liver function in septic rats. METHODS: Forty male Wistar rats were randomly divided into control group, model group, A. auricula-judae polysaccharide group and A. auricula-judae crude extract group. Septic model was induced by the procedure of cecal ligation and puncture (CLP). Intragastric administration was performed every 8 h 3 days prior to CLP. The plasma levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), endotoxin(ET), tumor necrosis factor α(TNF-α), interleukin 6(IL-6) and IL-1β were detected 12 h after CLP. The specimens of the liver were collected to observe the pathological changes. The expression of NF-κB in the liver tissues was detected by the method of immunohistochemistry. RESULTS: Compared with the CLP rats, the intervention of A. auricula-judae polysaccharide and A. auricula-judae crude extract to the septic rats significantly decreased the serum levels of ALT, AST, ET, TNF-α, IL-1β and IL-6 (P<005). The pathological changes of the liver tissues in treatment groups were significantly attenuated compared with CLP group. CONCLUSION: A. auricula-judae polysaccharide and A. auricula-judae crude extract protect liver against sepsis-induced injury by inhibiting the systemic inflammatory response.     

Changes of immune function and mortality in patients with sepsis-induced stress hyperglycemia

AIM: To investigate the role of stress hyperglycemia on condition assessment and predicting prognosis in patients with sepsis. METHODS: The study included 44 patients with sepsis, divided into three groups according to their blood glucose profile within 24 h after admission: patients with stress hyperglycemia (group SH, n=15), diabetes mellitus type 2 (group DM, n=10), and normal glucose levels (group NG, n=19). CD4+/CD8+ ratio, Th1/Th2 ratio and HLA-DR% of the patients were measured within 24 h after admission by flow cytometry as assessment of their immune function. The sepsis-related organ failure assessment (SOFA) scores and acute physiology and chronic health evaluation II (APACHE II) scores of patients were recorded at the same time to analyze whether stress hyperglycemia affects the immune function and the 28 d mortality in patients with sepsis. RESULTS: A higher mortality rate of septic patients with stress hyperglycemia was observed compared to diabetic patients (53.3% vs 10.0%) and group NG (53.3% vs 21.1%). SOFA score and APACHE II score were higher in group SH than those in group DM and group NG while lower levels of human leucocyte antigen DR (HLA-DR) expression and CD4+/CD8+ ratio was found in group SH than those in group DM and group NG. No difference in the levels of Th1/Th2 among the three groups was observed. Non-survivors had higher levels of SOFA score, APACHEⅡ score, Th1/Th2 ratio and HLA-DR%. No difference was detected for CD4+/CD8+ ratio, mean glucose values and age. CONCLUSION: Stress hyperglycemia is associated with decreased immune function and an adverse clinical outcome in patients with sepsis.     

Update on immunological pathway of negative regulation in development of sepsis

Sepsis is not only a primitively systemic inflammatory response to presumed or known infection, but also closely related to the immune status. In the initial stage of sepsis, a phase of immune activation could be evident, but a marked apoptosis-induced depletion of lymphocytes and a series of impairments in nonspecific immunological functions following severe trauma and burns appear to be responsible to the susceptibility of subsequent septic complications. Presently, negative regulation has been shown to play a pivotal role in the maintenance of peripheral homeostasis and regulation of immune responses. Understanding the basic immunological pathway of negative regulation should provide novel insights into the mechanisms of sepsis and immune homeostasis. This review provides a summary of the negative-regulatory pathways that are involved in the pathogenesis of sepsis.     

Heme oxygenase-1 protects renal function in septic rats via influencing expression of thrombomodulin

AIM: To investigate the protective effect of heme oxygenase-1 (HO-1) on the kidney of septic rats and the influence of HO-1 on the expression of thrombomodulin (TM) in the kidney. METHODS: Sepsis in rats was developed with cecal ligation and puncture (CLP). The septic rats were randomly divided into sham group, CLP group, CLP+HO-1 inducer group and CLP+HO-1 inhibitor group (n=18). The plasma levels of creatinine (Cr), cystatin-C (Cys-C), carboxyhemoglobin (COHb), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and TM, and the changes of prothrombin time (PT) and activated partial thromboplastin time (APTT) in each group were measured. Histopathological examination was performed in the kidney. The expression of TM in the kidney tissue was detected by Western blot. RESULTS: Compared with sham group, significantly elevated plasma levels of Cr, Cys-C, TNF-α, IL-1β and TM (P<0.05), shortened PT and APTT (P<0.05), significantly increased microthrombus formation, and lowered TM expression in the kidney (P<0.05) of CLP group were observed. The administration of hemin lowered the plasma levels of Cr, Cys-C, TNF-α, IL-1β and TM (P<0.05), prolonged PT and APTT (P<0.05), attenuated microthrombus formation, and up-regulated the expression of TM in the kidney (P<0.05). In contrast, ZnPP had the opposite effects. CONCLUSION: HO-1 increases the expression of TM in the kidney and exerts anticoagulatory and antiinflammatory effects, thereby improving renal function in the septic rats.     

Protective effect of bactericidal/permeability-increasing protein on sepsis induced by intra-abdominal infection in rats

AIM:To investigate the protective effect of bactericidal/permeability-increasing protein (BPI) on sepsis induced by intra-abdominal infection in rats and its mechanism.METHODS:Intra-abdominal infection induced sepsis was reproduced by cecal ligation and puncture (CLP). BPI or equal volume of physiological saline was intra-abdominally given immediately after CLP and 12 hours after CLP respectively (2.5 mg/kg of BPI each time). Plasma endotoxin levels were determined with limulus amebocyte chromogenic assay.RESULTS:(1)The survival time in BPI group was significantly higher than in physiological saline (PS) group. (2)The values of MAP, LVSP, IP, d p /d t max and-d p /d t max in BPI group, although decreasing,were markedly higher than those in PS group. (3) Plasma glutamate-pyruvate transaminase and urea nitrogen levels in BPI group, though increasing, were significantly lower than those in PS group.(4) There was no significant change of plasma endotoxin levels in BPI group, while plasma endotoxin levels were markedly increased in PS group. There was significantly different between two groups. CONCLUSIONS:BPI has an obvious protective effect on intra-abdominal infection induced sepsis, which might be related to its antagonism against endotoxin.     

Transplantation of mouse fetus-derived MSCs alleviates physical fatigue in mouse

AIM:To observe the effect of mouse fetus-derived mesenchymal stem cell(MSC) transplantation on alleviating fatigue in mice. METHODS:MSCs were derived from the mouse fetus at 13.5 d. The 6-month-old BALB/c mice were randomly divided into non-swimming group, swimming control group and swimming+MSCs group. The mice in swimming+MSCs group were injected with fetus-derived MSCs through the tail vein, while the mice in non-swimming group and swimming control group were injected with equal volume of normal saline. The anti-fatigue activity was evaluated using a weight-loaded swimming test, along with the determination of blood urea nitrogen(BUN), blood lactic acid(BLA),and glycogen in the hepatic and muscular tissues 24 h later. The antioxidant activity was evaluated by determining the activity of superoxide dismutase(SOD) and the content of malondialdehyde(MDA). The cardiac functions were measured by echocardiography. RESULTS:Primary cultured cells were spindle-shaped in scattered colony. The cells in fifth passage grew parallelly or swirlingly. The cells expressed CD44 and CD105, but not CD34 or CD45. Inducing experiments showed that the cells differentiated into osteoblasts or adipocytes. Transplantation of MSCs alleviated fatigue in mice. In swimming+MSCs group, weight-loaded swimming time was longer, the levels of BUN, BLA, hepatic and muscular MDA were lower, and the levels of glycogen and SOD in the hepatic and muscular tissues were higher than those in control group. Stroke volume, cardiac output and left ventricular diastolic volume in swimming+MSCs group increased, indicating that the cardiac functions were enhanced. CONCLUSION: Transplantation of mouse fetus-derived MSCs alleviates physical fatigue.