Tanshinone IIA protects rabbits against LPS-induced disseminated intravascular coagulation (DIC)

Aim:

To evaluate the effects of tanshinone IIA (Tan IIA), a lipophilic diterpene from the Chinese herb Salvia miltiorrhiza, on lipopolysaccharide (LPS)-induced disseminated intravascular coagulation (DIC) in rabbits.

Methods:

LPS-induced DIC model was made in adult male New Zealand rabbits by continuous intravenous infusion of LPS (0.5 mg/kg) via marginal ear vein for 6 h. The animals were simultaneously administered with Tan IIA (1, 3 and 10 mg/kg) or heparin (500 000 IU/kg) through continuous infusion via the contralateral marginal ear vein for 6 h. Before and 2 and 6 h after the start of LPS infusion, blood samples were taken for biochemical analyses.

Results:

Continuous infusion of LPS into the rabbits gradually impaired the hemostatic parameters, damaged renal and liver functions, increased the plasma TNF-α level, and led to a high mortality rate (80%). Treatment of the rabbits with Tan IIA dose-dependently attenuated the increase in activated partial thromboplastin time (APTT), prothrombin time (PT) and fibrin-fibrinogen degradation products (FDP); ameliorated the decrease in plasma levels of fibrinogen and platelets; and reversed the decline in activity of protein C and antithrombin III. Meanwhile, the treatment significantly suppressed the increase in the plasma levels of aminotransferase, creatinine and TNF-α, and led to much lower mortality (46.7% and 26.7% for the medium- and high-dose groups). Treatment of the rabbits with the high dose of heparin also effectively improved the hemostatic parameters, ameliorated liver and renal injuries, and reduced the plasma level of TNF-α, and significantly reduced the mortality (33.3%).

Conclusion:

Tan IIA exerts a protective effect against DIC in rabbits.     

Antagonism by salvianolic acid B of lipopolysaccharide‐induced disseminated intravascular coagulation in rabbits

The aim of the present study was to investigate the effects of salvianolic acid B on lipopolysaccharide (LPS)‐induced disseminated intravascular coagulation (DIC) in rabbits. Continuous infusion of LPS was used to induce a DIC model in rabbits. Treatment with salvianolic acid B (1, 3 or 6 mg/kg) was started simultaneously with LPS infusion (0.5 mg/kg LPS in 60 mL saline; 10 mL/h over a period of 6 h) through the contralateral marginal ear vein. Activated partial thromboplastin time (APTT), prothrombin time (PT), platelet count and fibrinogen concentration were determined, as were plasma levels of fibrin–fibrinogen degradation products (FDP), alanine aminotransferase (ALT), blood urea nitrogen (BUN), protein C activity, antithrombin III (ATIII) and tumour necrosis factor (TNF)‐α concentration. The gradual impairment of haemostatic parameters was induced by continuous infusion of LPS. There were marked increases in APTT, PT, BUN, ALT and plasma TNF‐α and marked decreases in the platelet count, fibrinogen, FDP, protein C and ATIII. The intravenous administration of 1, 3 or 6 mg/kg salvianolic acid B attenuated the increases in APTT, PT, BUN, ALT and plasma TNF‐α and the decreases in fibrinogen, platelet, FDP, protein C and ATIII induced by LPS infusion. These observations indicate that salvianolic acid B has an effect against LPS‐induced DIC in rabbits.     

肝素防治产科播散性血管内凝血的临床观察

目的探讨肝素在防治产科播散性血管内凝血(DIC)中的作用。方法对收治的DIC、重度妊娠高血压综合征(重度妊高征)、过期流产共132例进行临床总结分析。结果DIC使用肝素18例，死亡率5．56％(1／18)；对照组中，重度妊高征发生DIC 2例，发生率为14．29％(2／14)，死亡1例；过期流产发生DIC 3例，发生率为18．75％(3／18)。肝素组中，重度妊高征、过期流产均无DIC发生。结论肝素作用于凝血过程的多个环节，根据DIC、重度妊高征、过期流产的病因及病理生理，肝素可作为主要的治疗手段；治疗DIC以少量多次使用为主，预防DIC则为25mg／d。     

Trametinib alleviates lipopolysaccharide-induced acute lung injury by inhibiting the MEK-ERK-Egr-1 pathway

Acute lung injury (ALI) is a devastating clinical disorder with a high mortality rate and for which there is no effective treatment. The main characteristic of ALI is uncontrolled inflammation, and macrophages play a critical role in the development of this disorder. Trametinib, an inhibitor of MAPK/ERK kinase (MEK) activity that possesses anti-inflammatory properties, has been approved for clinical use. Herein, the influence of trametinib and its underlying mechanism were investigated using a lipopolysaccharide (LPS)-induced murine ALI model. We found that trametinib treatment prevented the LPS-facilitated expression of proinflammatory mediators in macrophages, and this anti-inflammatory action was closely correlated with suppression of the MEK-ERK-early growth response (Egr)-1 pathway. Furthermore, trametinib treatment alleviated LPS-induced ALI in mice, and attenuated edema, proinflammatory mediator production, and neutrophil infiltration. Trametinib pretreatment also attenuated the MEK-ERK-Egr-1 pathway in lung tissues. In conclusion, these data demonstrate that trametinib pretreatment suppresses inflammation in LPS-activated macrophages in vitro and protects against murine ALI established by LPS administration in vivo through inhibition of the MEK-ERK-Egr-1 pathway. Therefore, trametinib might have therapeutic potential for ALI.     

The cardioprotection of calcitonin gene-related peptide-mediated preconditioning

Preconditioning induced by brief ischemia or hyperthermia or some drugs shows two phases, early and delayed protection. The cardioprotection afforded by preconditioning is related to stimulation of endogenous mediators release. Calcitonin gene-related peptide (CGRP), a major transmitter of capsaicin-sensitive sensory nerves, has recently been shown to play an important role in mediation of the preconditioning induced by brief ischemia or hyperthermia or by some drugs, and alpha-CGRP seems to play a major role in the mediation of delayed preconditioning. It has been shown that the cardioprotection afforded by CGRP-mediated preconditioning is due to inhibition of cardiac tumor necrosis factor-alpha (TNF-alpha) production, but not to the activation of the K(ATP) channel.     

Dexamethasone reduces lung eosinophilia,and VCAM-1 and ICAM-1 expression induced by Sephadex beads in rats

Airway eosinophilia is one of the key pathophysiologic features in asthma. The endothelial adhesion molecules, vascular cell adhesion molecule (VCAM-1) and intercellular adhesion molecule (ICAM-1), have previously been shown to play a crucial role in eosinophil recruitment into the inflamed airway. We have investigated the effects of dexamethasone on eosinophilia into the bronchoalveolar lavage fluid, and the upregulation of VCAM-1 and ICAM-1 expression, measured by immunoblotting, induced by i.v. injection of Sephadex beads into rats. The beads significantly increased the lung eosinophilia, and expression of VCAM-1 and ICAM-1 in the lung. Pretreatment with dexamethasone (0.1 to 2 mg/kg i.p.) strongly inhibited all the airway inflammatory events in a dose-dependent manner. In conclusion, glucocorticoids may be potent inhibitors of lung eosinophilia, at least in part, due to the prevention of the upregulation of VCAM-1 and ICAM-1 expression.     

Beneficial effect of a novel non-steroidal anti-inflammatory agent with basic character and antioxidant properties on experimental colitis in rats

Ulcerative colitis is a chronic disorder of unknown etiology. Conservative treatment remains empirical, even today. The aim of this study was to test the efficacy of a novel non-steroidal anti-inflammatory agent [5-(2-hydroxy-ethylamino)-1-cyclohexyl-2-pentanone] (compound A), with basic character and antioxidant properties on an experimental model of ulcerative colitis in rats. The effect of this compound was compared with that of methylprednisolone on the histological abnormalities and serum levels of tumor necrosis factor-alpha (TNF-alpha) in experimental colitis produced by 2,4,6-trinitrobenzenesulfonic acid (TNB). A total number of 24 rats were randomly assigned to one of four groups of six rats each. Group 1: colitis without treatment (disease control), group 2: normal animals (control), group 3: induction of experimental colitis treated with methylprednisolone (5.3 x 10(-3) mmol/kg i.v. every day for 7 days) and group 4: induction of experimental colitis plus administration of compound A (0.6 mmol/kg i.v. every day for 7 days). The administration of compound A resulted in a statistically significant reduction of the extent of tissue damage and of certain histological features (edema, inflammatory infiltration) (P<0.05). Compound A also resulted in a statistically significant reduction of the levels of serum TNF-alpha, compared to those of controls (P<0.005). The beneficial effect of this compound was probably due to the combination, on a single molecule, of anti-inflammatory and antioxidant properties as well as to its basic character. The reduction of the serum TNF-alpha levels could be one of the possible mechanism(s) of action of the compound. Further studies are necessary to establish the direct mechanism of action(s) of the drug and to evaluate its long-term efficacy and safety.     

DATS通过p38MAPK通路抑制LPS诱导的小鼠MH-S细胞TNF-α及IL-1β表达

目的探讨p38MAPK在二烯丙基三硫(DATS)抑制脂多糖(LPS)诱导小鼠肺泡巨噬细胞促炎细胞因子表达中的作用。方法体外培养MH-S细胞,用DATS和(或)LPS进行干预,Western blot检测细胞p38及磷酸化p38(p-p38)的表达;用LPS和(或)SB203580孵育细胞,反转录PCR检测细胞中TNF-α、IL-1βmRNA表达,Western blot检测细胞磷酸化(p-IκB)及非磷酸化IκB的表达。结果 LPS刺激MH-S细胞可导致p-p38表达增加,呈时间依赖性;用DATS(0.1、0.5、2.5、5.0 mg.L-1)预处理细胞30 min后再给予LPS刺激,p-p38表达呈剂量依赖性下降;单独DATS对p-p38表达无明显影响。p38特异性抑制剂SB203580可剂量依赖性地抑制LPS诱导的p-IκB蛋白、TNF-α及IL-1βmR-NA表达。结论 DATS可通过抑制p38MAPK通路抑制IκB磷酸化及NF-κB活化,进而下调LPS诱导小鼠肺泡巨噬细胞TNF-α、IL-1βmRNA表达。     

Role of poly(ADP-ribose) polymerase activation in endotoxin-induced cardiac collapse in rodents

Reactive oxygen and nitrogen species are overproduced in the cardiovascular system during circulatory shock. Oxidant-induced cell injury involves the activation of poly(ADP-ribose) polymerase (PARP). Using a dual approach of PARP-1 suppression, by genetic deletion or pharmacological inhibition with the new potent phenanthridinone PARP inhibitor PJ34 [the hydrochloride salt of N-(oxo-5,6-dihydro-phenanthridin-2-yl)-N,N-dimethylacetamide], we studied whether the impaired cardiac function in endotoxic shock is dependent upon the PARP pathway. Escherichia coli endotoxin (lipopolysaccharide, LPS) at 55 mg/kg, i.p., induced a severe depression of the systolic and diastolic contractile function, tachycardia, and a reduction in mean arterial blood pressure in both rats and mice. Treatment with PJ34 significantly improved cardiac function and increased the survival of rodents. In addition, LPS-induced depression of left ventricular performance was significantly less pronounced in PARP-1 knockout mice (PARP(-/-)) as compared with their wild-type littermates (PARP(+/+)). Thus, PARP activation in the cardiovascular system is an important contributory factor to the cardiac collapse and death associated with endotoxin shock.     

Anticoagulant failure in coagulopathic patients: PTT confounding and other pitfalls

Introduction: Devastating thromboses can complicate heparin-induced thrombocytopenia (HIT) and disseminated intravascular coagulation (DIC). In these disorders, acquired abnormalities of the partial thromboplastin time (PTT) and international normalized ratio (INR) can confound monitoring of PTT- and INR-adjusted anticoagulant therapies, contributing to treatment failure.

Areas covered: Illustrative patient cases of anticoagulant failure due to PTT and INR confounding are discussed. Four different scenarios of thrombosis progression associated with inappropriate anticoagulant interruption/underdosing, contributing to ischemic limb necrosis, are presented: i) PTT confounding of heparin therapy of warfarin-associated microthrombosis complicating cancer hypercoagulability; ii) PTT confounding of direct thrombin inhibitor (DTI) therapy complicating HIT-associated DIC; iii) INR confounding during argatroban–warfarin overlap of HIT-associated deep-vein thrombosis; and iv) PTT confounding of anticoagulant therapy during acute DIC/hepatic necrosis–ischemic limb necrosis syndrome.

Expert opinion: Abnormal coagulation test results at pre-treatment baseline can provide an important clue regarding the risk of subsequent anticoagulant failure due to PTT or INR confounding. Greater awareness of the potential for anticoagulant failure due to PTT and INR confounding could assist clinicians in management of prothrombotic coagulopathies, for example, by choosing alternative anticoagulants (e.g., fondaparinux, danaparoid) that are not monitored by global coagulation assays, or by obtaining specific drug levels (anti-factor Xa levels, DTI levels).     

支气管哮喘患儿治疗前后血清SOD、VIP、TNF-α和Lep水平变化的临床意义

目的:为了探讨支气管哮喘患儿治疗前后血清SOD、VIP、TNF-α和Lep水平变化的临床意义。方法:放射免疫分析和酶免疫分析测定了87例支气管哮喘患儿和60例正常儿的血清SOD、VIP、TNF-α和Lep水平并进行了比较性分析。结果:在治疗前,87例支气管哮喘患儿血清SOD和VIP水平较之60例正常儿明显降低(t SOD=3.018,t VIP=3.146,P均<0.01),而血清TNF-α和Lep水平明显增高(t TNF-α=4.637,P<0.001,t Lep=3.261,P<0.01)。在治疗后,87例支气管哮喘患儿血清SOD和VIP水平恢复至正常,较之正常儿无明显的差异(t SOD=1.586,t VIP=1.563,P均>0.05),而血清TNF-α和Lep水平明显降低,但相较之正常儿增高(t TNF-α=2.103,t Lep=2.243,Pall<0.05)。结论:SOD和VIP水平的测定是诊断支气管哮喘患儿的良好指标,而且在糖皮质激素综合治疗后,可以进行随访和疗效的考核。     

KF24345, an adenosine uptake inhibitor,ameliorates the severity and mortality of lethal acute pancreatitis via endogenous adenosine in mice

Adenosine protects against cellular damage and dysfunction under several adverse conditions including inflammation and ischemia. In this study, we examined the effects of 3-[1-(6,7-diethoxy-2-morpholinoquinazolin-4-yl)piperidin-4-yl]-1,6-dimethyl-2,4(1H,3H)-quinazolinedione hydrochloride (KF24345), an adenosine uptake inhibitor, on experimental acute pancreatitis induced by choline-deficient and ethionine-supplemented diet in mice. KF24345, administered with the diet onset and every 24 h thereafter, prevented hyperamylasemia, acinar cell injury and serum tumor necrosis factor-alpha elevation and ultimately decreased mortality. Therapeutic treatment with KF24345, which started 32 h after the diet onset, also decreased mortality. The beneficial effect of KF24345 on mortality was abolished by the pretreatment with 4-(2-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol (ZM 241385), a selective adenosine A(2A) receptor antagonist. An intravenous injection of KF24345 at 48 h after the diet onset increased plasma adenosine concentrations in mice with acute pancreatitis. These results suggest that KF24345 shows anti-pancreatitis effects via endogenous adenosine and adenosine A(2A) receptors. The adenosine uptake inhibition could be a new therapeutic approach for acute pancreatitis.     

Protection against lipopolysaccharide-induced sepsis and inhibition of interleukin-1beta and prostaglandin E2 synthesis by silymarin

Silymarin is known to have hepatoprotective and anticarcinogenic effects. Recently, anti-inflammatory effect of silymarin is attracting an increasing attention, but the mechanism of this effect is not fully understood. Here, we report that silymarin protected mice against lipopolysaccharide (LPS)-induced sepsis. In this model of sepsis, silymarin improved the rate of survival of LPS-treated mice from 6 to 38%. To further investigate the mechanism responsible for anti-septic effect of silymarin, we examined the inhibitory effect of silymarin on interleukin-1beta (IL-1beta) and prostaglandin E2 (PGE2) production in macrophages. Silymarin dose-dependently suppressed the LPS-induced production of IL-1beta and PGE2 in isolated mouse peritoneal macrophages and RAW 264.7 cells. Consistent with these results, the mRNA expression of IL-1beta and cyclooxygenase-2 was also completely blocked by silymarin in LPS-stimulated RAW 264.7 cells. Moreover, the LPS-induced DNA binding activity of nuclear factor-kappaB/Rel was also inhibited by silymarin in RAW 264.7 cells. Taken together, these results demonstrate that silymarin has a protective effect against endotoxin-induced sepsis, and suggest that this is mediated, at least in part, by the inhibitory effect of silymarin on the production of IL-1beta and PGE2.     

Pioglitazone,a specific ligand of peroxisome proliferator-activated receptor-gamma,accelerates gastric ulcer healing in rat

The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the nuclear hormone receptor superfamily that is involved in the control of inflammation and carcinogenesis. We determined the effect of the specific PPAR-gamma ligand, pioglitazone (5-40 mg/kg intragastrically), on the healing of acetic-acid gastric ulcers in rats. At day 8 after ulcer induction, the ulcer area, the gastric blood flow and mucosal expression of proinflammatory cytokines such as interleukin-1beta, tumour necrosis factor alpha (TNF-alpha) and cyclooxygenase-1, cyclooxygenase-2, constitutive nitric oxide synthase (cNOS), inducible nitric oxide synthase (iNOS) and heat shock protein 70 (HSP70) was determined. Pioglitazone reduced the area of gastric ulcers and raised significantly the gastric blood flow at the ulcer margin and downregulated the mRNA for interleukin-1beta, TNF-alpha, cyclooxygenase-2 and iNOS while cyclooxygenase-1 mRNA was not affected. The expression of PPAR-gamma mRNA was increased in the ulcerated gastric mucosa. We conclude that pioglitazone accelerates the healing of preexisting gastric ulcers due to the hyperemia at ulcer margin and the anti-inflammatory action including suppression of interleukin-1beta, TNF-alpha, cyclooxygenase-2 and iNOS and by an overexpression of HSP70.     

Effect of tocotrienols on iron-induced renal dysfunction and oxidative stress in rats

Ferric nitrilotriacetate (Fe-NTA) is a well-established nephrotoxic agent. This study was designed to investigate the modulatory effect of the subacute administration of tocotrienol-rich fraction (T3), a product from palm oil, and α-tocopherol (T) on Fe-NTA-induced renal injury and oxidative stress. Fe-NTA administration markedly increased blood urea nitrogen (BUN) and serum creatinine level, which was coupled with a marked lipid peroxidation, reduced activity of glutathione levels, and morphological alterations in rat kidney. Pretreatment with T3 (50?mg/kg/day) and T (50?mg/kg/day) for 7 days before Fe-NTA administration significantly reduced the serum creatinine and BUN levels, reduced lipid peroxidation in a significant manner, and restored levels of reduced glutathione and superoxide dismutase. T3 pretreatment also attenuated the serum tumor necrosis factor-alpha levels, as compared to pretreatment with T, and restored normal renal morphology. These findings suggest a strong correlation between iron-induced oxidative stress and renal dysfunction and point toward the protective effects of T3 in Fe-NTA-induced renal injury.     

Use of the A(2A) adenosine receptor as a physiological immunosuppressor and to engineer inflammation in vivo

Inflammation must be inhibited in order to treat, e.g., sepsis or autoimmune diseases or must be selectively enhanced to improve, for example, immunotherapies of tumors or the development of vaccines. Predictable enhancement of inflammation depends upon the knowledge of the "natural" pathways by which it is down-regulated in vivo. Extracellular adenosine and A(2A) adenosine (purinergic) receptors were identified recently as anti-inflammatory signals and as sensors of excessive inflammatory tissue damage, respectively (Ohta A and Sitkovsky M, Nature 2001;414:916-20). These molecules may function as an important part of a physiological "metabolic switch" mechanism, whereby the inflammatory stimuli-produced local tissue damage and hypoxia cause adenosine accumulation and signaling through cyclic AMP-elevating A(2A) adenosine receptors in a delayed negative feedback manner. Patterns of A(2A) receptor expression are activation- and differentiation-dependent, thereby allowing for the "acquisition" of an immunosuppressive "OFF button" and creation of a time-window for immunomodulation. Identification of A(2A) adenosine receptors as "natural" brakes of inflammation provided a useful framework for understanding how tissues regulate inflammation and how to enhance or decrease (engineer) inflammation by targeting this endogenous anti-inflammatory pathway. These findings point to the need of more detailed testing of anti-inflammatory agonists of A(2A) receptors and create a previously unrecognized strategy to enhance inflammation and targeted tissue damage by using antagonists of A(2A) receptors. It is important to further identify the contributions of different types of immune cells at different stages of the inflammatory processes in different tissues to enable the "tailored" treatments with drugs that modulate the signaling through A(2A) purinergic receptors.     

(Z)-5-(4-methoxybenzylidene) thiazolidine-2, 4-dione ameliorates the adjuvant-induced arthritis via inhibiting the migration of macrophage and down-regulating the cytokine mRNA expression

In our previous study, we have demonstrated that (Z)-5-(4-methoxybenzylidene) thiazolidine-2, 4-dione (SKLB010), a novel analogue of thiazolidinediones, showed protection against concanavalin A (Con A)-induced hepatitis via inhibiting the migration of macrophages and the expression of pro-inflammatory mediators. In present study, Transwell assay was applied to study the effects of SKLB010 on macrophage-like Raw264.7 cell migration and we investigated the effects of SKLB010 on NO generation in vitro. We also studied in vivo effects of SKLB010 on adjuvant-induced arthritis in Lewis rats by oral administration. It was proved that SKLB010 depressed cells migration and the production of NO in Raw264.7 cells in a dose-dependent way. Our results also indicated that oral administration of 50 mg/kg SKLB010 markedly resulted in a clear suppression of clinical signs compared to untreated groups, showing as markedly reduction of paw swelling and inhibition of body weight decreasing. The improvement in disease severity was accompanied by suppression of CD68-positive cells in knee joint and by inhibition of production in pro-inflammatory cytokines of TNF-α, IL-1β and IL-6 in serum. The elevated TNF-α, IL-1β and iNOS mRNA expression in tissue were down-regulated after treatment with SKLB010. SKLB010 also significantly inhibited the histological progress of RA. These data indicate that SKLB010 is a potent anti-inflammatory therapeutic agent targeting the inflammatory response of macrophages.