MKK3 depletion attenuates intestinal injury after traumatic hemorrhagic shock by restoring mitochondrial function.

BACKGROUND: Traumatic hemorrhagic shock (THS) is a complex pathophysiological process resulting in multiple organ failure. Intestinal barrier dysfunction is one of the mechanisms implicated in multiple organ failure. The present study aimed to explore the regulatory role of mitogen-activated protein kinase kinase 3 (MKK3) in THS-induced intestinal injury and to elucidate its potential mechanism. METHODS: Rats were subjected to trauma and hemorrhage to establish a THS animal model. MKK3-targeted lentiviral vectors were injected via the tail vein 72 h before modeling. Twelve hours post-modeling, the mean arterial pressure (MAP) and heart rate (HR) were monitored, and histological injury to the intestine was assessed via H&E staining and transmission electron microscopy. Mitochondrial function and mitochondrial reactive oxygen species (ROS) were evaluated. IEC-6 cells were exposed to hypoxia to mimic intestinal injury following THS in vitro. RESULTS: MKK3 deficiency alleviated intestinal injury and restored mitochondrial function in intestinal tissues from THS-induced rats and hypoxia-treated IEC-6 cells. In addition, MKK3 deficiency promoted Sirt1/PGC-1α-mediated mitochondrial biogenesis and restricted Pink1/Parkin-mediated mitophagy in the injured intestine and IEC-6 cells. Furthermore, the protective effect of MKK3 knockdown against hypoxia-induced mitochondrial damage was strengthened upon simultaneous LC3B/Pink1/Parkin knockdown or weakened upon simultaneous Sirt1 knockdown. CONCLUSION: MKK3 deficiency protected against intestinal injury induced by THS by promoting mitochondrial biogenesis and restricting excessive mitophagy.

EFFECT OF MIR-21-3P ON INTESTINAL INJURY IN RATS WITH TRAUMATIC HEMORRHAGIC SHOCK RESUSCITATED WITH THE SODIUM BICARBONATE RINGER'S SOLUTION.

ABSTRACT: Background : This study aims to determine the impact and mechanism of miR-21-3p on intestinal injury and intestinal glycocalyx during fluid resuscitation in traumatic hemorrhagic shock (THS), and the different impacts of sodium lactate Ringer's solution (LRS) and sodium bicarbonate Ringer's solution (BRS) for resuscitation on intestinal damage. Methods : A rat model of THS was induced by hemorrhage from the left femur fracture. The pathological changes of intestinal tissues and glycocalyx structure were observed by hematoxylin-eosin staining and transmission electron microscope. MiR-21-3p expression in intestinal tissues was detected by real-time quantitative polymerase chain reaction. The expression of glycocalyx-, cell junction-, and PI3K/Akt/NF-κB signaling pathway-related proteins was analyzed by western blot. Results : MiR-21-3p expression was increased in THS rats, which was suppressed by resuscitation with BRS. BRS or LRS aggravated the intestinal injury and damaged intestinal glycocalyx in THS rats. The expression of SDC-1, HPA, ß-catenin, MMP2, and MMP9 was upregulated, the expression of E-cad was downregulated, and the PI3K/Akt/NF-κB signaling pathway was activated in THS rats, which were further aggravated by BRS or LRS. The adverse effect of LRS was more serious than BRS. MiR-21-3p overexpression deteriorated the injury of intestinal tissues and intestinal glycocalyx; increased the expression of SDC-1, HPA, ß-catenin, MMP2, and MMP9 while decreasing E-cad expression; and activated the PI3K/Akt/NF-κB signaling pathway in BRS-resuscitated THS rats. Conclusion : MiR-21-3p aggravated intestinal tissue injury and intestinal glycocalyx damage through activating PI3K/Akt/NF-κB signaling pathway in rats with THS resuscitated with BRS.

Magnesium hydride attenuates intestinal barrier injury during hemorrhage shock by regulating neutrophil extracellular trap formation via the ROS/MAPK/PAD4 pathway.

Magnesium hydride (MgH2) is a hydrogen storage material that is known for its high capacity and safety and is capable of releasing hydrogen in a controlled manner when administered orally. This release of hydrogen has been associated with a range of biological effects, including anti-inflammatory properties, antioxidant activity, and protection of the intestinal barrier. Previous research has shown that neutrophil extracellular traps (NETs) play a role in the dysfunction of the intestinal barrier in conditions such as sepsis and critical illnesses. However, it remains unclear as to whether MgH2 can protect the intestinal barrier by inhibiting NET formation, and the underlying mechanisms have yet to be elucidated. A rat model of hemorrhagic shock was created, and pretreatment or posttreatment procedures with MgH2 were performed. After 24 h, samples from the small intestine and blood were collected for analysis. In vitro, human neutrophils were incubated with either phorbol-12-myristate-13-acetate (PMA) or MgH2. Reactive oxygen species generation and the expression of key proteins were assessed. The results demonstrated that MgH2 administration led to a decrease in inflammatory cytokines in the serum and mitigated distant organ dysfunction in rats with HS. Furthermore, MgH2 treatment reversed histopathological damage in the intestines, improved intestinal permeability, and enhanced the expression of tight junction proteins (TJPs) during HS. Additionally, MgH2 treatment was found to suppress NET formation in the intestines. In vitro pretreatment with MgH2 alleviated intestinal monolayer barrier disruption that was induced by NETs. Mechanistically, MgH2 pretreatment reduced ROS production and NET formation, inhibited the activation of ERK and p38, and suppressed the expression of the PAD4 protein. These findings indicated that MgH2 may inhibit NET formation in a ROS/MAPK/PAD4-dependent manner, which reduces NET-related intestinal barrier damage, thus offering a novel protective role in preventing intestinal barrier dysfunction during HS.

Effect of sodium bicarbonate Ringer's solution on lung injury in rats with traumatic hemorrhagic shock.

This study aimed to explore the impact of different pH values of resuscitation fluid on traumatic hemorrhagic shock (THS), focusing on their effects on glycocalyx and inflammation. A rat model of THS was induced by hemorrhage from a left femur fracture, while an oxygen-glucose deprivation/reoxygenation (OGD/R)-induced HULEC-5a cell model was considered as an in vitro THS model. The lung tissue pathology and glycocalyx structure were assessed through hematoxylin-eosin (H&E) staining and transmission electron microscope examination. The levels of glycocalyx-related factors and inflammation-related factors were determined by enzyme-linked immunosorbent assay (ELISA). The expression of glycocalyx-related proteins, cell junction-related proteins, and proteins involved in the PI3K/Akt/NF-κB signaling pathway was analyzed by western blot. The results showed that both sodium bicarbonate Ringer's solution (BRS) and lactate Ringer's solution (LRS) were effective in restoring mean arterial pressure and heart rate in THS rats. However, LRS has a stronger impact on promoting inflammation and damaging the glycocalyx compared with BRS. In OGD/R-induced HULEC-5a cells, a pH of 7.4 and 6.5 increased inflammation and disrupted the glycocalyx, while a pH of 8.1 had no significant effect on inflammation or glycocalyx. Furthermore, the PI3K/Akt/NF-κB signaling pathway was activated by fluid resuscitation and different pH values. However, the activating effect of BRS and pH 8.1 on the PI3K/Akt/NF-κB signaling pathway was milder compared with LRS and pH6.5. In conclusion, an alkaline recovery environment was more beneficial for the treatment of THS.

Construction of a Nomogram Model for Predicting Pleural Effusion Secondary to Severe Acute Pancreatitis.

Background: This study aims to investigate the risk factors of pleural effusion (PE) secondary to severe acute pancreatitis (SAP) and to build a nomogram model. Methods: The clinical parameters of SAP patients admitted to the emergency department of the First Affiliated Hospital of Bengbu Medical College from January 2019 to August 2021 were retrospectively collected. The independence risk factors of PE secondary to SAP were analyzed by univariate analysis and multivariate logistic regression analysis. A nomogram risk prediction model was established and validated through the area under the ROC curve. Result: Two hundred twenty-two SAP patients were included for analysis, of which 65 patients experienced secondary PE. The incidence of PE secondary to SAP was 29.28% (65/222). Logistic regression analysis showed that serum albumin (ALB) (OR = 0.830, 95% CI: 0.736∼0.936), fibrinogen (FIB) (OR = 4.573, 95% CI: 1.795∼11.648), C-reactive protein (CRP) (OR = 1.046, 95% CI: 1.009∼1.083), acute physiology, chronic health score system (APACHE-II) score (OR = 1.484, 95% CI: 1.106∼1.990), and sequential organ failure score (SOFA) (OR = 43.038, 95% CI: 2.030∼4.548) were independent risk factors for PE secondary to SAP (P < 0.05) and entered into the nomogram. The nomogram showed robust discrimination with an index of concordance of 0.755 and an area under the receiver operating characteristic curve of 0.837 (95% CI: 0.779∼0.894). Conclusion: We developed a nomogram model for PE secondary to SAP with ALB, FIB, CRP, APACHE-II scores, and SOFA scores. The nomogram model showed good discrimination and consistency, and it can better predict the risk of PE secondary to SAP.

Effect of miR-21-3p on lung injury in rats with traumatic hemorrhagic shock resuscitated with sodium bicarbonate Ringer's solution.

Background: Restricted fluid resuscitation is the most important early method for treating traumatic hemorrhagic shock (THS). This study sought to explore whether micro ribonucleic acid (miR)-21-3p affected resuscitated THS rats by regulating the glycocalyx and inflammation. Methods: MiRNAs extracted from the lung tissues were analyzed by miRNA microarray assays. A rat model of THS was induced by hemorrhage from a left femur fracture. The pathological change in the lung tissues and glycocalyx structure was observed by hematoxylin and eosin staining and a transmission electron microscope examination. The miR-21-3p expression in the lung tissues and serum was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The levels of glycocalyx-related factors and inflammation-related factors were determined by enzyme linked immunosorbent assays. The expression of glycocalyx-related proteins, cell junction-related proteins, and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/nuclear factor kappa B (NF-κB) signaling pathway-related proteins was analyzed by Western blot. Results: After RT-qPCR verification, the variation trend of miR-21-3p was in line with expected trends. The mean arterial pressure (MAP) and heart rate (HR) were decreased, and the lung injury and damage to the glycocalyx were all aggravated in the THS rats resuscitated with sodium bicarbonate Ringer's solution (BRS) or sodium lactate Ringer's solution (LRS). The expression of miR-21-3p was decreased in the THS rats resuscitated with BRS and increased in the THS rats resuscitated with LRS, and the upregulation of miR-21-3p further decreased the MAP and HR, and increased the levels of syndecan-1 (SDC-1), heparanase-1 (HPA1), interleukin (IL)-6, IL-1ß, and tumor necrosis factor alpha (TNF-α) in the serum of the THS rats resuscitated with BRS. The upregulation of miR-21-3p also increased the expression of SDC-1, HPA1, ß-catenin, matrix metallopeptidase (MMP)2, and MMP9, but decreased the expression of E-cadherin (E-cad) and activated the PI3K/Akt/NF-κB signaling pathway in the THS rats resuscitated with BRS and transfected with miR-21-3p compared to that of the THS rats resuscitated with BRS and transfected with miR-negative control (NC). Conclusions: miR-21-3p promoted inflammation and glycocalyx damage by activating the PI3K/Akt/NF-κB signaling pathway, thereby aggravating the lung injury in the THS rats resuscitated with BRS.

Protective effect of Lactobacillus-containing probiotics on intestinal mucosa of rats experiencing traumatic hemorrhagic shock.

This study was conducted to assess whether Lactobacillus-containing probiotics could protect intestinal mucosa in rats during traumatic hemorrhagic shock and to determine its underlying mechanisms. Healthy male Sprague-Dawley rats (300 ± 20 g) were randomly divided into four groups. During the study, reverse transcription polymerase chain reaction, western blotting, and hematoxylin and eosin methods were used. There was a significant increase in the expression of toll-like receptor 4 (TLR4) in the rats that experienced traumatic hemorrhagic shock, along with increased mRNA of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6. Pretreatment with Lactobacillus-containing probiotics reduced TLR4 expression, decreased phosphorylation (Ser536) and acetylation (Lys310) of p65, and decreased TNF-α and IL-6 mRNA. The probiotics combined acetate Ringer's group showed a less severe pathological manifestation compared to the other experimental groups. Lactobacillus-containing probiotics inhibited nuclear factor-kappa B signaling via the downregulation of TLR4, resulting in inflammatory homeostasis, which might be the mechanism whereby Lactobacillus protects the intestinal mucosa from damage caused by the traumatic hemorrhagic shock.

Blockade of JAK2 signaling produces immunomodulatory effect to preserve pancreatic homeostasis in severe acute pancreatitis.

JAK/STAT plays an important role in cytokine signal transduction and it is potentially involved in the proinflammatory response during the early phase of severe acute pancreatitis (SAP). However, whether JAK2 activity is upregulated and whether JAK2 inhibition plays a role in the maintenance of pancreatic homeostasis during SAP is incompletely understood. Here we show that JAK2/STAT3 activity is highly elevated in SAP and blockade of JAK2 by AG-490 protects against SAP-induced pancreatic inflammation and injury. Gene expression and ELISA studies showed that JAK2 inhibition altered the cytokine profiles in both the circulation and pancreases. Further analysis revealed that JAK2 inhibition restored the level of cytokines critical for macrophage polarization towards M2 macrophage. Our findings suggest that pharmacological targeting at JAK2/STAT signalling may be an effective choice of therapeutic interventions against SAP.

Efficacy of Microecopharmaceutics Combined with Early Enteral Nutrition Support in the Treatment of Severe Acute Pancreatitis.

To explore the efficacy of microecopharmaceutics combined with early enteral nutrition support to the treatment of severe acute pancreatitis (SAP). A total of 26 patients diagnosed with SAP in our hospital were retrospectively reviewed. Microecopharmaceutics, the living microbial food supplements that are beneficial to the host by improving the balance of intestinal microorganisms, were combined with early enteral nutrition group, and used as the treatment group; and delayed enteral nutrition was used as the control group. Two weeks after both treatments, variables of C-reactive protein (CRP), albumin (Alb), total serum protein (TP), urinary amylase recovery time, hemodiastase recovery time, acute physiology and chronic health evaluation (APCHE) score, and hospitalisation time in both groups were compared. Alb and TP of the treatment group were significantly higher than those in the control group (p <0.05). The APCHE score and CRP in the treatment group were significantly lower than those in the control group (p <0.05). The urinary amylase recovery time, hemodiastase amylase recovery time, and hospitalisation time in the treatment group were significantly shorter than those in the control group. The use of microecopharmaceutics combined with early enteral nutrition can effectively protect the intestinal barrier function, which is an effective treatment in patients with SAP.

[Mechanism of ulinastatin in reducing lung inflammatory injury in rats with hemorrhagic shock].

OBJECTIVE: To investigate the effect of ulinastatin on the inflammatory mediators and their signaling pathways miR-146a/TLR4/NF-κB in rats with hemorrhagic shock. METHODS: Seventy-two SD rats were randomly assigned into shock without resuscitation group (SR group, n=24), acetated Ringer's solution resuscitation group (AR group, n=24) and ulinastatin treatment group (n=24). In all the 3 groups hemorrhagic shock models were established by femoral artery bleeding (with the mean arterial pressure maintained at 30-40 mmHg) without resuscitation (in SR group) or with resuscitation (in AR and ulinastatin groups) using acetated Ringer's solution for 30 min at 60 min after the onset of shock. At 1, 4, and 6 h after the shock onset or immediately after shock if the rats died, the lung tissues were taken for measurement of mRNA expressions of miR-146a, tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), IL-4, IL-6 and IL-10 using real-time quantitative PCR and the protein expressions of TLR4, MyD88, IκB-α, p-IκB-α, NF-κB p65, IRAK4, p-IRAK4 (Thr345, Ser346), p-IRAK4 (Thr342) and TRAF6 using Western blotting. The lung histopathology of the rats was examined under optical microscope with HE staining. RESULTS: Compared with the SR group, the rats in the AR group showed slightly alleviated inflammatory infiltration in the lung tissues with significantly increased mRNA levels of miR-146a, IL-4 and IL-10 (P < 0.05) and protein expressions of IκB-α, p-IRAK4 (Thr342) and p-IRAK4 (Thr345, ser346) (P < 0.05), and decreased mRNA levels of TNF-α, IL-1 and IL-6 (P < 0.05) and protein expressions of TLR4, MyD88, NF-κB p65, p-IκB-α, IRAK-4 and TRAF6 (P < 0.05). Compared with those in AR group, the rats in ulinastatin group showed further alleviation of inflammatory lung tissue injury, with increased mRNA levels of miR-146a, IL-4 and IL-10 (P < 0.01) and protein expressions of IκB-α, p-IRAK4 and p-IRAK4 (P < 0.01) and decreased mRNA levels of TNF-α, IL-1 and IL-6 (P < 0.01) and protein expressions of TLR4, MyD88, NF-κB p65, p-IκB-α, IRAK-4 and TRAF6 (P < 0.01). CONCLUSIONS: Ulinastatin combined with acetated Ringer's solution resuscitation alleviates lung inflammations in rats with hemorrhagic shock possibly by enhancing miR-146a expression to regulate TLR4/NF-κB signaling pathway through a negative feedback mechanism and thus modulate the balance of pro-inflammatory and anti-inflammatory factors.

[Effects of different target blood pressure resuscitation on peripheral blood inflammatory factors and hemodynamics in patients with traumatic hemorrhagic shock].

OBJECTIVE: To investigate the target blood pressure level of restrictive fluid resuscitation in patients with traumatic hemorrhagic shock. METHODS: Sixty patients with traumatic hemorrhagic shock admitted to the First Affiliated Hospital of Bengbu Medical College from January 2016 to December 2018 were enrolled. All patients were resuscitated with sodium acetate ringer solution after admission. According to the difference of mean arterial pressure (MAP) target, the patients were divided into low MAP (60 mmHg ≤ MAP < 65 mmHg, 1 mmHg = 0.133 kPa), middle MAP (65 mmHg ≤ MAP < 70 mmHg) and high MAP (70 mmHg ≤ MAP < 75 mmHg) groups by random number table using the admission order with 20 patients in each group. Those who failed to reach the target MAP after 30-minute resuscitation were excluded and supplementary cases were deferred. The restrictive fluid resuscitation phase was divided into three phases: before fluid resuscitation, liquid resuscitation for 30 minutes and 60 minutes. The most suitable resuscitation blood pressure level was further speculated by monitoring the inflammatory markers and hemodynamics in different periods in each group of patients. Pearson correlation analysis was used to detect the correlation of variables. RESULTS: Before fluid resuscitation, there was no significant difference in hemodynamics or expressions of serum cytokines among the three groups. Three groups of patients were resuscitated for 30 minutes to achieve the target blood pressure level and maintain 30 minutes. With the prolongation of fluid resuscitation time, the central venous pressure (CVP), cardiac output (CO) and cardiac index (CI) were increased slowly in the three groups, and reached a steady state at about 30 minutes after resuscitation, especially in the high MAP group and the middle MAP group. The expressions of serum inflammatory factors in the three groups were gradually increased with the prolongation of fluid resuscitation time. Compared with the low MAP group and the high MAP group, after 30 minutes of resuscitation the middle MAP group was superior to the other two groups in inhibiting the expressions of pro-inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and promoting anti-inflammatory factors IL-10 [TNF-α mRNA (2-ΔΔCt): 0.21±0.13 vs. 0.69±0.34, 0.57±0.35; IL-6 mRNA (2-ΔΔCt): 0.35±0.31 vs. 0.72±0.39, 0.59±0.42; IL-10 mRNA (2-ΔΔCt): 1.25±0.81 vs. 0.61±0.46, 0.82±0.53; all P < 0.05], but there was no significant difference in promoting the expression of IL-4 mRNA among three groups. At 60 minutes of resuscitation, compared with the low MAP group and the high MAP group, the middle MAP group could significantly inhibit the expressions of TNF-α, IL-6 and promote IL-10 [TNF-α mRNA (2-ΔΔCt): 0.72±0.35 vs. 1.05±0.54, 1.03±0.49; IL-6 mRNA (2-ΔΔCt): 0.57±0.50 vs. 1.27±0.72, 1.01±0.64; IL-10 mRNA (2-ΔΔCt): 1.41±0.90 vs. 0.81±0.48, 0.94±0.61; all P < 0.05]. Compared with the high MAP group, the middle MAP group had significant differences in promoting the expression of IL-4 mRNA (2-ΔΔCt: 1.32±0.62 vs. 0.91±0.60, P < 0.05). There was no significant difference in serum cytokine expressions at different time points of resuscitation between the low MAP group and the high MAP group (all P > 0.05). Correlation analysis showed that there was a strong linear correlation between MAP and mRNA expressions of TNF-α, IL-6, IL-10 in the middle MAP group (r value was 0.766, 0.719, 0.692, respectively, all P < 0.01), but had no correlation with IL-4 (r = 0.361, P = 0.059). Fitting linear regression analysis showed an increase in 1 mmHg per MAP, the expression of TNF-α mRNA increased by 0.027 [95% confidence interval (95%CI) = 0.023-0.031, P < 0.001], IL-6 mRNA increased by 0.021 (95%CI = 0.017-0.024, P < 0.001), and IL-10 mRNA increased by 0.049 (95%CI = 0.041-0.058, P < 0.001). CONCLUSIONS: When patients with traumatic hemorrhagic shock received restrict fluid resuscitation at MAP of 65-70 mmHg, the effect of reducing systemic inflammatory response and improving hemodynamics is better than the target MAP at 60-65 mmHg or 70-75 mmHg. It is suggested that 65-70 mmHg may be an ideal target MAP level for restrictive fluid resuscitation.