Pachymic Acid Prevents Hemorrhagic Shock-Induced Cardiac Injury by Suppressing M1 Macrophage Polarization and NF-[Formula: see text]B Signaling Pathway.

Hemorrhagic shock (HS) is the leading cause of death in trauma patients. Inflammation following HS can lead to cardiac damage. Pachymic acid (PA), a triterpenoid extracted from Poria cocos, has been found to possess various biological activities, including anti-inflammatory and anti-apoptotic properties. Our research aims to investigate the protective effects of PA against HS-induced heart damage and the underlying mechanisms involved. Male Sprague-Dawley rats were intraperitoneally injected with PA (7.5 or 15[Formula: see text]mg/kg) daily for three days. Subsequently, we created a rat model of HS by drawing blood through a catheter inserted into the femoral artery followed by resuscitation. The results revealed that HS led to abnormalities in hemodynamics, serum cardiac enzyme levels, and cardiac structure, as well as induced cardiac apoptosis. However, pretreatment with PA effectively alleviated these effects. PA-pretreatment also suppressed mRNA and protein levels of interleukin (IL)-1[Formula: see text], IL-6, and tumor necrosis factor [Formula: see text] (TNF-[Formula: see text]) in the heart tissues of HS rats. Additionally, PA-pretreatment reduced inflammatory cell infiltration and M1 macrophage polarization while exaggerating M2 polarization in HS rat hearts. The study observed a decreased proportion of the expression of of M1 macrophages (CD86[Formula: see text]) and their marker (iNOS), along with an increased proportion of the expression of M2 macrophages (CD206[Formula: see text]) and their marker (Arg-1). Notably, PA-pretreatment suppressed NF-[Formula: see text]B pathway activation via inhibiting NF-[Formula: see text]B p65 phosphorylation and its nuclear translocation. In conclusion, PA-pretreatment ameliorates HS-induced cardiac injury, potentially through its inhibition of the NF-[Formula: see text]B pathway. Therefore, PA treatment holds promise as a strategy for mitigating cardiac damage in HS.

Trauma-induced hypocalcemia.

BACKGROUND: Trauma-induced hypocalcemia is an underappreciated complication of severe injury but is well known to result in the derangement of an array of physiological regulatory mechanisms. Existing literature provides a compelling link between hypocalcemia and worse trauma-induced coagulopathy and increased mortality after injury. STUDY DESIGN AND METHODS: This narrative review evaluates available data related to the risk factors, mechanisms, and treatment of hypocalcemia after severe injury. The authors did not perform a systemic review or meta-analysis. RESULTS AND DISCUSSION: The interplay of acidosis, hypothermia, and coagulopathy with hypocalcemia potentiates the bloody vicious cycle of hemorrhagic shock which has been the paradigm of trauma resuscitation for over half a century. However, current screening and treatment of postinjury hypocalcemia are relegated to a secondary consideration in trauma resuscitation. We conclude calcium supplementation should be a primary tier intervention for life-threatening injury.

Clinical Features, Management and Maternal-Infant Prognosis in Patients with Complete Uterine Rupture in the Second and Third Trimester of Pregnancy.

Objectives: Our study aimed to investigate the clinical features, management, and maternal-infant prognosis in patients with complete uterine rupture in the second and third trimester of pregnancy. Methods: A total of 15 patients with complete uterine rupture in their second and third trimester of pregnancy who were admitted to our hospital between January 2012 and December 2020 were included in our study. The patients enrolled were divided into the scar group (11 patients) and the non-scar group (4 patients) according to the existence or absence of a uterine scar. The general data, clinical characteristics and follow-up results in the 2 groups were compared. Results: There was no significant difference in age, pregnancy duration or delivery cycle between the 2 groups (P > .05). The incidence of original scar rupture in the scar group was significantly higher than in the non-scar group (P > .05). No significant difference was found in clinical characteristics between the scar and the non-scar groups (P > .05). The most common clinical features included abdominal pain, inability to lie flat, hemorrhagic shock, prenatal vaginal bleeding and uterine rupture, mostly occurring in the lower segments of the uterus and cervix. A total of 3 patients were misdiagnosed as having surgical disease. After completing relevant examinations, the uterine rupture was repaired surgically; the patients were discharged after blood transfusion, and their condition resolved. In all, 3 patients in the non-scar group and 1 patient in the scar group were transferred to the intensive care unit (ICU). All 15 patients were discharged after treatment. Follow-up was completed by all patients for 12 to 36 months, with an average follow-up time of 23.09 ± 2.19 months. Of the 15 patients, 2 underwent induced abortion after 24 months due to unplanned pregnancy. A 5-minute Apgar score of ≤7 in the scar group was higher than that in the non-scar group, but the difference was not statistically significant (P > .05). Perinatal mortality in the 15 patients was 40.00% (6/15). Conclusion: The most common clinical features in patients with complete uterine rupture in the second and third trimester of pregnancy included abdominal pain, inability to lie flat, hemorrhagic shock, prenatal vaginal bleeding and uterine rupture, mostly occurring in the lower segments of the uterus and cervix. In addition, a remarkably worse maternal-infant prognosis was seen in patients with complete uterine rupture in the second and third trimester of scarless pregnancy compared with patients with complete uterine rupture in the second and third trimester of scarred pregnancy.

Protective effect of Shenfu on gut epithelium in a porcine model of hemorrhagic shock.

This study aimed to explore the protective effect of Shenfu on the hemodynamics and gut integrity in a porcine model of hemorrhagic shock. Hemorrhagic shock was induced in 32 domestic pigs with a rapid bleeding via the arterial sheath to a mean arterial pressure of 40 mm Hg within 10 min. Animals with hemorrhagic shock were then randomly assigned into the negative control group (n=8), receiving neither blood transfusion nor drug treatment; the blood transfusion group, in which animals were given blood transfusion alone; the saline group, in which animals were blood transfused and resuscitated with saline (3 mL/kg); and the Shenfu group, in which animals received blood transfusion and resuscitation with Shenfu (3 mL/kg). Blood tumor necrosis factor-alpha (TNF-ɑ) and interleukin-6 were measured using ELISAs. Tissue levels of superoxide dismutase (SOD), malondialdehyde (MDA), Na+/K+-ATPase, Ca++ATPase, myeloperoxidase (MPO), and fatty acid binding protein 2 (FABP2) were determined using respective quantitation kits. Fluid resuscitation with Shenfu significantly improved HR, CI, and MAP of pig with hemorrhagic shock, which was accompanied with mitigation of tissue damages in intestinal epithelium. Blood TNF-ɑ was reduced in the Shenfu group. Bcl-2 and cleaved caspase-3 expression in intestinal tissues were elevated and decreased, respectively, in pigs treated with Shenfu. Notably, treatment with Shenfu suppressed oxidative stress markers MDA, MPO, and FABP2 in the intestine. Oppositely, SOD, Na+/K+-ATPase and Ca++ATPase levels in intestinal tissues were promoted by Shenfu treatment. Shenfu demonstrates significant protective effect on the hemodynamics and gut epithelium of pigs with hemorrhagic shock.

Shenfu injection improves cerebral microcirculation and reduces brain injury in a porcine model of hemorrhagic shock.

BACKGROUND: Shenfu injection (SFI) is a traditional Chinese herbal medicine which has been clinically used for treatment of septic shock and cardiac shock. The aim of this study was to clarify effects of SFI on cerebral microcirculation and brain injury after hemorrhagic shock (HS). METHODS: Twenty-one domestic male Beijing Landrace pigs were randomly divided into three groups: SFI group (SFI, n = 8), saline group (SA, n = 8) or sham operation group (SO, n = 5). In the SFI group, animals were induced to HS by rapid bleeding to a mean arterial pressure of 40 mmHg within 10 minutes and maintained at 40±3 mmHg for 60 minutes. Volume resuscitation (shed blood and crystalloid) and SFI were given after 1 hour of HS. In the SA group, animals received the same dose of saline instead of SFI. In the SO group, the same surgical procedure was performed but without inducing HS and volume resuscitation. The cerebral microvascular flow index (MFI), nitric oxide synthase (NOS) expression, aquaporin-4 expression, interleukin-6, tumor necrosis factor-α (TNF-α) and ultrastructural of microvascular endothelia were measured. RESULTS: Compared with the SA group, SFI significantly improved cerebral MFI after HS. SFI up regulated cerebral endothelial NOS expression, but down regulated interleukin-6, TNF-α, inducible NOS and aquaporin-4 expression compared with the SA group. The cerebral microvascular endothelial injury and interstitial edema in the SFI group were lighter than those in the SA group. CONCLUSIONS: Combined application of SFI with volume resuscitation after HS can improve cerebral microcirculation and reduce brain injury.

Intense Light Pretreatment Improves Hemodynamics, Barrier Function and Inflammation in a Murine Model of Hemorrhagic Shock Lung.

INTRODUCTION: Hemorrhagic shock is a primary injury amongst combat casualties. Hemorrhagic shock can lead to acute lung injury, which has a high mortality rate. Based on studies showing the role of intense light for organ-protection, we sought to evaluate if intense light pretreatment would be protective in a murine model of hemorrhagic shock lung. MATERIALS AND METHODS: After exposure to standard room light or to intense light (10 000 LUX), mice were hemorrhaged for 90 minutes to maintain a mean arterial pressure (MAP) of 30-35 mmHg. Mice were then resuscitated with their blood and a NaCl infusion at a rate of 0.2 ml/h over a 3-hour period. During resuscitation, blood pressure was recorded. At the end of resuscitation, bronchoalveolar lavage was analyzed for alveolar epithelial barrier function and inflammation. To get insight into the relevance of intense light for humans, we performed a proteomics screen for lung injury biomarkers in plasma from healthy volunteers following intense light therapy. RESULTS: We found that intense light pretreated mice had improved hemodynamics and significantly lower albumin, IL-6, and IL-8 levels in their bronchoalveolar lavage than controls. We further discovered that intense light therapy in humans significantly downregulated proinflammatory plasma proteins that are known to cause acute lung injury. CONCLUSIONS: Our data demonstrate that mice exposed to intense light before hemorrhagic shock lung have less lung inflammation and improved alveolar epithelial barrier function. We further show that intense light therapy downregulates lung injury promoting proteins in human plasma. Together, these data suggest intense light as a possible strategy to ameliorate the consequences of a hemorrhagic shock on lung injury.

Pyruvate Protects Against Intestinal Injury by Inhibiting the JAK/STAT Signaling Pathway in Rats With Hemorrhagic Shock.

BACKGROUND: This study aimed to investigate the role of Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway in protection by peritoneal resuscitation (PR) using pyruvate-peritoneal dialysis solution (PY-PDS) against intestinal injury from hemorrhagic shock (HS) in rats. MATERIALS AND METHODS: Sixty-four rats were assigned to eight groups: group SHAM; group intravenous resuscitation (VR); groups NS, LA, and PY in which the rats were subjected to HS and PR with normal saline (NS), lactate-peritoneal dialysis solution (LA-PDS), and PY-PDS, respectively, combined with VR; and groups DMSO, RPM, and AG490 in which the rats were subjected to HS and VR with pretreatment of dimethyl sulfoxide (DMSO), rapamycin (RPM), and tyrphostin B42 (AG490). RESULTS: At 2 h after HS and resuscitation, the levels of diamine oxidase, 15-F2t-isoprostane, thromboxane B2, and endothelin-1, in the blood and the intestinal mucosal apoptotic index and caspase-3 were lower in groups PY, RPM, and AG490 than in groups VR, NS, LA, and DMSO. Group PY showed lower levels of malondialdehyde and myeloperoxidase and a higher level of superoxide dismutase than groups VR, NS, and LA. Phosphorylated JAK2 and phosphorylated STAT3 levels were lower in groups PY, RPM, AG490, and LA than in groups VR, NS, and DMSO. CONCLUSIONS: The protection mechanism of PR with PY-PDS combined with VR was related to the inhibition of the JAK/STAT signaling pathway during HS and resuscitation. The process might include suppression of oxidative stress, reduction of neutrophil infiltration, regulation of microcirculation, and inhibition of apoptosis.

Early intravenous administration of tranexamic acid ameliorates intestinal barrier injury induced by neutrophil extracellular traps in a rat model of trauma/hemorrhagic shock.

BACKGROUND: Early intravenous administration of tranexamic acid has been shown to protect the intestinal barrier after a model of trauma-hemorrhagic shock in the rat, but the potential mechanism remains unclear. Our previous studies have demonstrated that neutrophil extracellular traps contribute to the intestinal barrier dysfunction during sepsis and other critical conditions. Meanwhile, there are high levels of neutrophil infiltration in the intestine during trauma-hemorrhagic shock. Here, we hypothesized that neutrophil extracellular trap formation played a vital role during trauma-hemorrhagic shock-induced intestinal injury and that tranexamic acid, a serine protease inhibitor, may inhibit neutrophil extracellular trap formation and protect intestinal barrier function in trauma-hemorrhagic shock. METHODS: A model of trauma-hemorrhagic shock in male rats was established. The rats were divided into 6 groups: (1) sham group; (2) trauma-hemorrhagic shock group; (3) trauma-hemorrhagic shock + DNase I group; (4) trauma-hemorrhagic shock + tranexamic acid group; (5) trauma-hemorrhagic shock + tranexamic acid (different time) group; and (6) trauma-hemorrhagic shock + tranexamic acid (different doses) group. The DNase I solution was injected intravenously to disrupt neutrophil extracellular traps immediately after the trauma-hemorrhagic shock model was completed. After 24 hours, the small intestine and blood were collected for analysis. Human neutrophils were harvested and incubated with phorbol-12-myristate-13-acetate or tranexamic acid, generation of reactive oxygen species, and key proteins expression were detected. RESULTS: Trauma-hemorrhagic shock induced the formation of intestinal neutrophil extracellular traps and disrupted the intestinal tight junction proteins. Clearing of neutrophil extracellular traps by DNase I resulted in increased expression of tight junction proteins and alleviated the intestinal injury. Early intravenous tranexamic acid administration (1 hour after trauma-hemorrhagic shock) decreased neutrophil extracellular trap formation and prevented tight junction protein disruption compared to the non-tranexamic acid group; however, after delayed administration of tranexamic acid (6 hours), there were no changes in neutrophil extracellular trap formation and intestinal injuries compared to the non-tranexamic acid group. Furthermore, tranexamic acid inhibited neutrophil extracellular trap formation and protected the intestinal barrier in a dose-dependent manner and high-dose (20 mg/kg) treatment of tranexamic acid showed a better effect compared with the therapeutic dose (10 mg/kg). The results of thromboelastography demonstrated that the R and K values in the high-dose group decreased (R, 1.85 ± 0.14 vs 3.87 ± 0.16 minutes, P < .001; K, 0.95 ± 0.04 vs 1.48 ± 0.07 minutes, P < .001), accompanied by a decrease in LY30, indicating that treatment with a high dose of tranexamic acid may cause hypercoagulability and shutdown of fibrinolysis. In addition, less neutrophil extracellular trap formation was detected in neutrophils incubated with neutrophils via an reactive oxygen species-dependent pathway. CONCLUSION: We first demonstrated a novel role of neutrophil extracellular traps in the pathophysiology of intestinal barrier dysfunction during trauma-hemorrhagic shock. Notably, early but not delayed intravenous administration of tranexamic acid effectively inhibits neutrophil extracellular trap formation and protects intestinal barrier function. Therefore, these results suggested a potential theoretic intervention for the protection of the intestinal barrier during trauma-hemorrhagic shock. In such a process, tranexamic acid appears to regulate neutrophil extracellular trap formation via the classic reactive oxygen species/mitogen-activated protein kinase pathway.

The therapeutic effects of microRNAs in preclinical studies of acute kidney injury: a systematic review protocol.

BACKGROUND: Acute kidney injury (AKI) causes significant morbidity and mortality in humans, and there are currently no effective treatments to enhance renal recovery. MicroRNAs (miRNAs) are short chain nucleotides that regulate protein expression and have been implicated in the pathogenesis of AKI. Recently, preclinical studies in vivo have uncovered a therapeutic role for administration of specific miRNAs in AKI. However, the overall benefits of this strategy in preclinical studies have not been systematically reviewed, and the potential for translation to human studies is unclear. AIM: The primary aim is to conduct a systematic review of the therapeutic properties of miRNAs in preclinical studies of AKI. The secondary aim is to determine potential adverse effects of miRNA administration in these studies. METHODS: A comprehensive search strategy will identify relevant studies in AKI in vivo models, using the MEDLINE, EMBASE, OVID, PUBMED, and Web of Science databases. The search strategy will include terms for mammalian (non-human) AKI models, including injury related to ischemia/reperfusion, nephrotoxicity, sepsis, contrast agents, cardio-pulmonary bypass, and hemorrhagic shock. Interventions will be defined as direct administration of exogenous miRNAs or antagonists of miRNAs, as well as maneuvers that alter expression of miRNAs that are mechanistically linked to AKI outcomes. The primary outcomes will be indices of kidney function and structure, and there will be no restriction on comparator interventions. Two independent investigators will initially screen abstracts, and selected articles that meet eligibility criteria will be reviewed for data abstraction and analysis. The SYRCLE RoB tool for animal studies will determine risk of bias, and meta-analysis will be performed as appropriate. The GRADE methodology will assess the quality of evidence. DISCUSSION: The administration of selective miRNA mimics or antagonists exerts beneficial effects in mammalian models of AKI, although multiple obstacles must be addressed prior to translation to human clinical trials. The proposed systematic review will document key miRNA candidates, and determine effect size estimates and sources of outcome bias. The review will also identify gaps in knowledge and guide future directions in AKI research. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019128854.

Trigeminal Nerve Stimulation: A Novel Method of Resuscitation for Hemorrhagic Shock.

OBJECTIVES: To determine if trigeminal nerve stimulation can ameliorate the consequences of acute blood loss and improve survival after severe hemorrhagic shock. DESIGN: Animal study. SETTING: University research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Severe hemorrhagic shock was induced in rats by withdrawing blood until the mean arterial blood pressure reached 27 ± 1 mm Hg for the first 5 minutes and then maintained at 27 ± 2 mm Hg for 30 minutes. The rats were randomly assigned to either control, vehicle, or trigeminal nerve stimulation treatment groups. The effects of trigeminal nerve stimulation on survival rate, autonomic nervous system activity, hemodynamics, brain perfusion, catecholamine release, and systemic inflammation after severe hemorrhagic shock in the absence of fluid resuscitation were analyzed. MEASUREMENTS AND MAIN RESULTS: Trigeminal nerve stimulation significantly increased the short-term survival of rats following severe hemorrhagic shock in the absence of fluid resuscitation. The survival rate at 60 minutes was 90% in trigeminal nerve stimulation treatment group whereas 0% in control group (p < 0.001). Trigeminal nerve stimulation elicited strong synergistic coactivation of the sympathetic and parasympathetic nervous system as measured by heart rate variability. Without volume expansion with fluid resuscitation, trigeminal nerve stimulation significantly attenuated sympathetic hyperactivity paralleled by increase in parasympathetic tone, delayed hemodynamic decompensation, and improved brain perfusion following severe hemorrhagic shock. Furthermore, trigeminal nerve stimulation generated sympathetically mediated low-frequency oscillatory patterns of systemic blood pressure associated with an increased tolerance to central hypovolemia and increased levels of circulating norepinephrine levels. Trigeminal nerve stimulation also decreased systemic inflammation compared with the vehicle. CONCLUSIONS: Trigeminal nerve stimulation was explored as a novel resuscitation strategy in an animal model of hemorrhagic shock. The results of this study showed that the stimulation of trigeminal nerve modulates both sympathetic and parasympathetic nervous system activity to activate an endogenous pressor response, improve cerebral perfusion, and decrease inflammation, thereby improving survival.

Myocardial Electrical Remodeling and the Arrhythmogenic Substrate in Hemorrhagic Shock-Induced Heart: Anti-Arrhythmogenic Effect of Liposome-Encapsulated Hemoglobin (HbV) on the Myocardium.

INTRODUCTION: Prolonged low blood pressure <40 mmHg in hemorrhagic shock (HS) causes irreversible heart dysfunction, 'Shock Heart Syndrome' (SHS), which is associated with lethal arrhythmias (ventricular tachycardia or ventricular fibrillation [VT/VF]) leading to a poor prognosis. METHODS: To investigate whether the liposome-encapsulated human hemoglobin oxygen carrier (HbV) is comparable in effectiveness to autologous washed red blood cells (wRBCs) for improving arrhythmogenic properties in SHS, optical mapping analysis (OMP), electrophysiological study (EPS), and pathological examinations were performed in Sprague-Dawley rat hearts obtained from rats subjected to acute HS by withdrawing 30% of total blood volume. After acute HS, the rats were immediately resuscitated by transfusing exactly the same amount of saline (SAL), 5% albumin (5% ALB), HbV, or wRBCs. After excising the heart, OMP and EPS were performed in Langendorff-perfused hearts. RESULTS: OMP showed a tendency for abnormal conduction and significantly impaired action potential duration dispersion (APDd) in both ventricles with SAL and 5% ALB. In contrast, myocardial conduction and APDd were substantially preserved with HbV and wRBCs. Sustained VT/VF was easily provoked by a burst pacing stimulus to the left ventricle with SAL and 5% ALB. No VT/VF was induced with HbV and wRBCs. Pathology showed myocardial structural damage characterized by worse myocardial cell damage and Connexin43 with SAL and 5% ALB, whereas it was attenuated with HbV and wRBCs. CONCLUSIONS: Ventricular structural remodeling after HS causes VT/VF in the presence of APDd. Transfusion of HbV prevents VT/VF, similarly to transfusion of wRBCs, by preventing electrical remodeling and preserving myocardial structures in HS-induced SHS.

N-Acetylcysteine and Desferoxamine Reduce Pulmonary Oxidative Stress Caused by Hemorrhagic Shock in a Porcine Model.

AIM OF THE STUDY: To investigate the pulmonary oxidative stress and possible protective effect of N-Acetylcysteine (NAC) and Desferoxamine (DFX)in a porcine model subjected to hemorrhagic shock. MATERIALS AND METHODS: Twenty-one pigs were randomly allocated to Group-A (sham, n = 5), Group-B (fluid resuscitation, n = 8) and Group-C (fluid, NAC and DFX resuscitation, n = 8). Groups B and C were subjected to a 40-min shock period induced by liver trauma, followed by a 60-min resuscitation period. During shock, the mean arterial pressure (MAP) was maintained at 30-40 mmHg. Resuscitation consisted of crystalloids (35 mL/kg) and colloids (18 mL/kg) targeting to MAP normalization (baseline values ± 10%). In addition, Group-C received pretreatment with NAC 200 mg/kg plus DFX 2 g as intravenous infusions. Thiobarbituric Acid Reactive Substances (TBARS), protein carbonyls and glutathione peroxidase (GPx) activity were determined in lung tissue homogenates. Also, histological examination of pulmonary tissue specimens was performed. RESULTS: TBARS were higher in Group-B than in Group-A or Group-C: 2.90 ± 0.47, 0.57 ± 0.10, 1.78 ± 0.47 pmol/µg protein, respectively (p < 0.05). Protein carbonyls content was higher in Group-B than in Group-A or Group-C: 3.22 ± 0.68, 0.89 ± 0.30, 1.95 ± 0.54 nmol/mg protein, respectively (p > 0.05). GPx activity did not differ significantly between the three groups (p > 0.05). Lung histology was improved in Group-C versus Group-B, with less alveolar collapse, interstitial edema and inflammation. CONCLUSION: NAC plus DFX prevented the increase of pulmonary oxidative stress markers and protein damage after resuscitated hemorrhagic shock and had beneficial effect on lung histology. NAC/DFX combination may be used in the multimodal treatment of hemorrhagic shock, since it may significantly prevent free radical injury in the lung.

Sodium tanshinone IIA sulfonate attenuates hemorrhagic shock-induced organ damages by nuclear factor-kappa B pathway.

BACKGROUND: Trauma resulted hemorrhagic shock (HS) leads to increased oxidative stress and inflammatory responses, which contributes greatly to organ failure or dysfunction. Tanshinone IIA sulfonate (TSA), as an antioxidant, may potentially be used in fluid resuscitation to prevent HS-induced organ damages. METHODS: In this study, a rat HS model was constructed. HS rats received TSA or vehicle drug during resuscitation. Mean arterial pressure and factors associated with organ failure or dysfunction, oxidative stress, and inflammatory response were investigated to evaluate treatment responses. Expression of proteins in NF-кB pathway was evaluated to elucidate the mechanism of TSA in preventing HS-induced organ damage. RESULTS: Although HS induced organ damage and upregulated oxidative stress and inflammatory response, TSA treatment ameliorated organ dysfunction, reduced oxidative stress, and suppressed inflammatory responses. We also showed that TSA treatment attenuated HS-induced activation in NF-кB pathway. CONCLUSIONS: TSA can potentially serve as an antioxidant for ameliorating HS-induced organ failure or function. Its mechanism of action may be through inhibiting NF-кB pathway.

N-3 Polyunsaturated Fatty Acids Improve Liver Lipid Oxidation-Related Enzyme Levels and Increased the Peroxisome Proliferator-Activated Receptor α Expression Level in Mice Subjected to Hemorrhagic Shock/Resuscitation.

Appropriate metabolic interventions after hemorrhagic shock/resuscitation injury have not yet been identified. We aimed to examine the effects of fish oil on lipid metabolic intervention after hemorrhagic shock/resuscitation. Firstly, 48 C57BL/6 mice were assigned to six groups (n = 8 per group). The sham group did not undergo surgery, while mice in the remaining groups were sacrificed 1-5 days after hemorrhagic shock/resuscitation. In the second part, mice were treated with saline or fish oil (n = 8 per group) five days after injury. We determined serum triglyceride levels and liver tissues were collected and prepared for qRT-PCR or Western blot analysis. We found that triglyceride levels were increased five days after hemorrhagic shock/resuscitation, but decreased after addition of fish oil. After injury, the protein and gene expression of carnitine palmitoyltransferase 1A, fatty acid transport protein 1, and peroxisome proliferator-activated receptor-α decreased significantly in liver tissue. In contrast, after treatment with fish oil, the expression levels of these targets increased compared with those in the saline group. The present results suggest n-3 polyunsaturated fatty acids could improve lipid oxidation-related enzymes in liver subjected to hemorrhagic shock/resuscitation. This function is possibly accomplished through activating the peroxisome proliferator-activated receptor-α pathway.

Osthol attenuates neutrophilic oxidative stress and hemorrhagic shock-induced lung injury via inhibition of phosphodiesterase 4.

Oxidative stress caused by neutrophils is an important pathogenic factor in trauma/hemorrhagic (T/H)-induced acute lung injury (ALI). Osthol, a natural coumarin found in traditional medicinal plants, has therapeutic potential in various diseases. However, the pharmacological effects of osthol in human neutrophils and its molecular mechanism of action remain elusive. In this study, our data showed that osthol potently inhibited the production of superoxide anion (O2(•-)) and reactive oxidants derived therefrom as well as expression of CD11b in N-formylmethionylleucylphenylalanine (FMLP)-activated human neutrophils. However, osthol inhibited neutrophil degranulation only slightly and it failed to inhibit the activity of subcellular NADPH oxidase. FMLP-induced phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) was inhibited by osthol. Notably, osthol increased the cAMP concentration and protein kinase A (PKA) activity in activated neutrophils. PKA inhibitors reversed the inhibitory effects of osthol, suggesting that these are mediated through cAMP/PKA-dependent inhibition of ERK and Akt activation. Furthermore, the activity of cAMP-specific phosphodiesterase (PDE) 4, but not PDE3 or PDE7, was significantly reduced by osthol. In addition, osthol reduced myeloperoxidase activity and pulmonary edema in rats subjected to T/H shock. In conclusion, our data suggest that osthol has effective anti-inflammatory activity in human neutrophils through the suppression of PDE4 and protects significantly against T/H shock-induced ALI in rats. Osthol may have potential for future clinical application as a novel adjunct therapy to treat lung inflammation caused by adverse circulatory conditions.

The therapeutic effect and mechanism of niacin on acute lung injury in a rat model of hemorrhagic shock: Down-regulation of the reactive oxygen species-dependent nuclear factor κB pathway.

BACKGROUND: The purpose of the current study was to investigate the protective effect of niacin on acute lung injury by the down-regulation of the nuclear factor κB (NF-κB) pathway in hemorrhagic shock (HS) rats. METHODS: HS was induced in male Sprague-Dawley rats by withdrawing blood to maintain a mean arterial pressure of 20 mm Hg to 25 mm Hg for 40 minutes. The rats were resuscitated by the reinfusion of the drawn blood, and a vehicle (HS), a low-dose of niacin (360 mg/kg, HS + LD-NA), or a high dose of niacin (1,080 mg/kg, HS + HD-NA) were administered orally. The survival of the subjects was observed for 72 hours, and a separate set of animals was killed at 6 hours after HS induction. We measured cytoplasmic phosphorylated inhibitor κB-α and inhibitor κB-α expressions, nuclear NF-κB p65 expression, NF-κB p65 DNA-binding activity, MEK partner 1 activity, tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), IL-8, nicotinamide adenine dinucleotide (NAD+), reduced nicotinamide adenine dinucleotide phosphate, reduced glutathione, glutathione disulfide, malondialdehyde levels, and histologic damage in the lung tissue. We also measured TNF-α, IL-6, and IL-8 levels in the serum. RESULTS: The survival rates of the sham, HS, HS + LD-NA, and HS + HD-NA groups were 6 of 6 (100%), 0 of 9 (0%), 1 of 9 (11.1%), and 3 of 9 (33.3%), respectively. A high dose of niacin increased lung NAD+, nicotinamide adenine dinucleotide phosphate levels, and glutathione-glutathione disulfide ratios; decreased lung malondialdehyde levels; down-regulated the NF-κB pathway; suppressed TNF-α, IL-6, and IL-8 levels in the lung tissue and serum; and attenuated histologic lung damage. CONCLUSION: A high dose of niacin attenuated lung inflammation, suppressed proinflammatory cytokine release, reduced histologic lung damage, and improved survival after HS in rats. Its therapeutic benefits were associated with the down-regulation of the reactive oxygen species-dependent NF-κB pathway.

Hydrogen sulfide in posthemorrhagic shock mesenteric lymph drainage alleviates kidney injury in rats.

Posthemorrhagic shock mesenteric lymph (PHSML) is a key factor in multiple organ injury following hemorrhagic shock. We investigated the role of hydrogen sulfide (H2S) in PHSML drainage in alleviating acute kidney injury (AKI) by administering D,L-propargylglycine (PPG) and sodium hydrosulfide hydrate (NaHS) to 12 specific pathogen-free male Wistar rats with PHSML drainage. A hemorrhagic shock model was established in 4 experimental groups: shock, shock+drainage, shock+drainage+PPG (45 mg/kg, 0.5 h prehemorrhage), and shock+drainage+NaHS (28 µmol/kg, 0.5 h prehemorrhage). Fluid resuscitation was performed after 1 h of hypotension, and PHMSL was drained in the last three groups for 3 h after resuscitation. Renal function and histomorphology were assessed along with levels of H2S, cystathionine-γ-lyase (CSE), Toll-like receptor 4 (TLR4), interleukin (IL)-10, IL-12, and tumor necrosis factor (TNF)-α in renal tissue. Hemorrhagic shock induced AKI with increased urea and creatinine levels in plasma and higher H2S, CSE, TLR4, IL-10, IL-12, and TNF-α levels in renal tissue. PHSML drainage significantly reduced urea, creatinine, H2S, CSE, and TNF-α but not TLR4, IL-10, or IL-12. PPG decreased creatinine, H2S, IL-10, and TNF-α levels, but this effect was reversed by NaHS administration. In conclusion, PHSML drainage alleviated AKI following hemorrhagic shock by preventing increases in H2S and H2S-mediated inflammation.

Fibrinogen and prothrombin complex concentrate in trauma coagulopathy.

BACKGROUND: Coagulopathy after injury contributes to hemorrhage and death. Treatment with specific coagulation factors could decrease hemorrhage and mortality. Our aim was to compare fibrinogen and prothrombin complex concentrate (PCC) in a rabbit model of hemorrhagic shock. MATERIALS AND METHODS: New Zealand white rabbits were anesthetized. Blood was withdrawn to a mean arterial pressure (MAP) of 30-40 mm Hg for 30 min. Animals were resuscitated with lactated Ringer to a MAP of 50-60 mm Hg and randomized to receive 100 mg/kg of fibrinogen, PCC 25 IU/kg, or lactated Ringer. A liver injury was created. A MAP of 50-60 mm Hg was maintained for 60 min. The primary outcome was blood loss, and secondary outcomes were fluid administered and coagulopathy as measured by plasma-based tests. RESULTS: There were eight animals in each group. Median blood loss was significantly higher in the fibrinogen group, at 122 mL (95% confidence interval [CI], 75-194), when compared with that in the control group, 35 mL (95% CI, 23-46; P value = 0.001), and the PCC group, 26 mL (95% CI, 4-54; P value = 0.002). Resuscitation fluid requirement was highest in the fibrinogen group, at 374 mL (95% CI, 274-519), and lowest in the PCC group, at 238 mL (95% CI, 212-309) (P = 0.01). Plasma-based coagulation tests were not different among groups. CONCLUSIONS: In a rabbit model, PCC did not have a significant effect on blood loss. Fibrinogen increased blood loss and fluid requirements.

Protection against intestinal injury from hemorrhagic shock by direct peritoneal resuscitation with pyruvate in rats.

OBJECTIVE: We explored the effects of direct peritoneal resuscitation with pyruvate-peritoneal dialysis solution (PDS) following intravenous resuscitation (VR) on intestinal ischemia-reperfusion injury in rats with hemorrhagic shock (HS). METHODS: Fifty rats were randomly assigned equally to five groups. In group sham, a surgical operation was performed on rats without shock or resuscitation. In group VR, rats were subjected only to VR. In groups NS, LA, and PY, direct peritoneal resuscitation was performed with normal saline (NS), lactate-based PDS (Lac-PDS), and pyruvate-based PDS (Pyr-PDS), respectively, after VR. Mean arterial pressure was monitored in the right common carotid artery. Two hours after resuscitation, the lactate level in arterial blood and the wet weight/dry weight ratio of the intestine were determined. The intestinal mucosal damage index was estimated, and ultrastructural changes in the intestinal mucosa were observed. Malondialdehyde, myeloperoxidase, nitric oxide, and tumor necrosis factor α levels were also measured. RESULTS: Two hours after HS and resuscitation, the increase in arterial blood lactate and intestinal wet weight/dry weight ratio declined significantly in rats from Groups LA and PY compared with groups VR and NS, whereas group PY was more advantageous in the changes of these parameters. The intestinal mucosal damage index and ultrastructural changes were also improved in groups LA and PY when compared with groups VR and NS. Protection was more apparent with Pyr-PDS than Lac-PDS. Hemorrhagic shock resulted in a significant increase in malondialdehyde levels and myeloperoxidase activity and was accompanied by overexpression of tumor necrosis factor α and a reduction in nitric oxide levels. These changes were significantly attenuated by Lac-PDS and Pyr-PDS at 2 h after resuscitation, and Pyr-PDS showed more effective protection for the intestine than Lac-PDS. CONCLUSIONS: Direct peritoneal resuscitation with Lac-PDS and Pyr-PDS after VR alleviated intestinal injury from HS in rats, and Pyr-PDS was superior to Lac-PDS in its protective effect. Mechanisms of action might include the elimination of free oxygen radicals, reduction of neutrophil infiltration, inhibition of the inflammatory response, and regulation of intestinal mucosal blood flow and barrier function.

A sphingosine-1 phosphate agonist (FTY720) limits trauma/hemorrhagic shock-induced multiple organ dysfunction syndrome.

BACKGROUND: Trauma/hemorrhagic shock (T/HS) is one of the major consequences of battlefield injury as well as civilian trauma. FTY720 (sphingosine-1-phosphate agonist) has the capability to decrease the activity of the innate and adaptive immune systems and, at the same time, maintain endothelial cell barrier function and vascular homeostasis during stress. For this reason, we hypothesize that FTY720, as part of resuscitation therapy, would limit T/HS-induced multiple organ dysfunction syndrome in a rodent T/HS model. METHODS: Rats subjected to trauma/sham shock (T/SS) or T/HS (30 mm Hg × 90 min) were administered FTY720 (1 mg/kg) post-T/HS during volume resuscitation. Lung injury (permeability to Evans blue dye), polymorphonuclear leukocyte (PMN) priming (respiratory burst activity), and red blood cell (RBC) rigidity were measured. In addition, lymph duct-cannulated rats were used to quantify the effect of FTY720 on gut injury (permeability and morphology) and the biologic activity of T/HS versus T/SS lymph on PMN-RBC and RBC deformability. RESULTS: Trauma/hemorrhagic shock-induced increased lung permeability, PMN priming, and RBC rigidity were all abrogated by FTY720. The systemic protective effect of FTY720 was only partially at the gut level, because FTY720 did not prevent T/HS-induced gut injury (morphology or permeability); however, it did abrogate T/HS lymph-induced increased respiratory burst and RBC rigidity. CONCLUSIONS: FTY720 limited T/HS-induced multiple organ dysfunction syndrome (lung injury, red cell injury, and neutrophil priming) as well as T/HS lymph bioactivity, although it did not limit gut injury.