Crtc1 deficiency protects against sepsis-associated acute lung injury through activating akt signaling pathway.

BACKGROUND: Interplay between systemic inflammation and programmed cell death contributes to the pathogenesis of acute lung injury (ALI). cAMP-regulated transcriptional coactivator 1 (CRTC1) has been involved in the normal function of the pulmonary system, but its role in ALI remains unclear. METHODS AND RESULTS: We generated a Crtc1 knockout (KO; Crtc1-/-) mouse line. Sepsis-induced ALI was established by cecal ligation and puncture (CLP) for 24 h. The data showed that Ctrc1 KO substantially ameliorated CLP-induced ALI phenotypes, including improved lung structure destruction, reduced pulmonary vascular permeability, diminished levels of proinflammatory cytokines and chemokines, compared with the wildtype mice. Consistently, in lipopolysaccharide (LPS)-treated RAW264.7 cells, Crtc1 knockdown significantly inhibited the expression of inflammatory effectors, including TNF-α, IL-1ß, IL-6 and CXCL1, whereas their expressions were significantly enhanced by Crtc1 overexpression. Moreover, both Crtc1 KO in mice and its knockdown in RAW264.7 cells dramatically reduced TUNEL-positive cells and the expression of pro-apoptotic proteins. In contrast, Crtc1 overexpression led to an increase in the pro-apoptotic proteins and LPS-induced TUNEL-positive cells. Mechanically, we found that the phosphorylation of Akt was significantly enhanced by Crtc1 knockout or knockdown, but suppressed by Crtc1 overexpression. Administration of Triciribine, an Akt inhibitor, substantially blocked the protection of Crtc1 knockdown on LPS-induced inflammation and cell death in RAW264.7 cells. CONCLUSIONS: Our study demonstrates that CRTC1 contribute to the pathological processes of inflammation and apoptosis in sepsis-induced ALI, and provides mechanistic insights into the molecular function of CRTC1 in the lung. Targeting CRTC1 would be a promising strategy to treat sepsis-induced ALI in clinic.

Artesunate alleviates intestinal ischemia/reperfusion induced acute lung injury via up-regulating AKT and HO-1 signal pathway in mice.

Acute Lung injury (ALI) is a common complication following intestinal ischemia/reperfusion (II/R) injury that can lead to acute respiratory distress syndrome (ARDS) a fatal illness for there is no specific therapy. The semisynthetic artemisinin Artesunate (Art) extracted from Artemisia annua has been found lots of pharmaceutical effects such as anti-malaria, anti-inflammatory, and anti-apoptosis. This study aimed to investigate the effect of Artesunate on intestinal ischemia/reperfusion and the mechanism of how Artesunate works in mice. To establish the II/R model, the C57BL/c mice were subjected to occlude superior mesenteric artery (SMA) for 45 min and 120 min reperfusion, and the lung tissue was collected for examination. Severe lung injury occurred during the II/R, meanwhile Art pretreatment decreased the lung injury score, wet/dry ratio, the level of MDA, MPO, IL-1ß, TNFα, CXCL1, MCP-1, the TUNEL-positive cells, Bax and Cleaved-Caspase3 protein expression obviously, and increased the activity of SOD and the expression of Bcl-2. In addition, the protein of P-AKT and HO-1 were upregulated during the Art pretreatment. Then the AKT inhibitor Triciribin and HO-1 inhibitor Tin-protoporphyrin IX were administered which reversed the protein expression of apoptosis, AKT and HO-1. Our study suggests that Art mitigated the II/R induced acute lung injury by targeting the oxidative stress, inflammatory response and apoptosis which is associated with the activating of AKT and HO-1, providing novel insights into the therapeutic candidate for the treatment of II/R induced acute lung injury.

Serinc2 deficiency causes susceptibility to sepsis-associated acute lung injury.

BACKGROUND: Severe sepsis and its subsequent complications cause high morbidity and mortality rates worldwide. The lung is one of the most vulnerable organs sensitive to the sepsis-associated inflammatory storm and usually develops into acute respiratory distress syndrome (ARDS)/acute lung injury (ALI). The pathogenesis of sepsis-associated ALI is accompanied by coordinated transmembrane signal transduction and subsequent programmed cell death; however, the underlying mechanism remains largely unclear. RESULTS: Here we find that the expression of serine incorporator 2 (Serinc2), a protein involved in phosphatidylserine synthesis and membrane incorporation, is upregulated in cecal ligation and puncture (CLP)-induced ALI. Furthermore, the Serinc2-knockout (KO) mouse line is generated by the CRISPR-cas9 approach. Compared with wild-type mice, the Serinc2-KO mice exhibit exacerbated ALI-related pathologies after CLP. The expressions of pro-inflammatory factors, including IL1ß, IL6, TNFα, and MCP1, are significantly enhanced by Serinc2 deficiency, concurrent with over-activation of STAT3, p38 and ERK pathways. Conversely, Serinc2 overexpression in RAW264.7 cells significantly suppresses the inflammatory responses induced by lipopolysaccharide (LPS). Serinc2 KO aggravates CLP-induced apoptosis as evidenced by increases in TUNEL-positive staining, Bax expression, and cleaved caspase-3 and decreases in BCL-2 expression and Akt phosphorylation, whereas these changes are suppressed by Serinc2 overexpression in LPS-treated RAW264.7 cells. Moreover, the administration of AKTin, an inhibitor of Akt, abolishes the protective effects of Serinc2 overexpression against inflammation and apoptosis. CONCLUSIONS: Our findings demonstrate a protective role of Serinc2 in the lung through activating the Akt pathway, and provide novel insight into the pathogenesis of sepsis-induced ALI.

ß-caryophyllene, an FDA-Approved Food Additive, Inhibits Methamphetamine-Taking and Methamphetamine-Seeking Behaviors Possibly via CB2 and Non-CB2 Receptor Mechanisms.

Recent research indicates that brain cannabinoid CB2 receptors are involved in drug reward and addiction. However, it is unclear whether ß-caryophyllene (BCP), a natural product with a CB2 receptor agonist profile, has therapeutic effects on methamphetamine (METH) abuse and dependence. In this study, we used animal models of self-administration, electrical brain-stimulation reward (BSR) and in vivo microdialysis to explore the effects of BCP on METH-taking and METH-seeking behavior. We found that systemic administration of BCP dose-dependently inhibited METH self-administration under both fixed-ratio and progressive-ratio reinforcement schedules in rats, indicating that BCP reduces METH reward, METH intake, and incentive motivation to seek and take METH. The attenuating effects of BCP were partially blocked by AM 630, a selective CB2 receptor antagonist. Genetic deletion of CB2 receptors in CB2-knockout (CB2-KO) mice also blocked low dose BCP-induced reduction in METH self-administration, suggesting possible involvement of a CB2 receptor mechanism. However, at high doses, BCP produced a reduction in METH self-administration in CB2-KO mice in a manner similar as in WT mice, suggesting that non-CB2 receptor mechanisms underlie high dose BCP-produced effects. In addition, BCP dose-dependently attenuated METH-enhanced electrical BSR and inhibited METH-primed and cue-induced reinstatement of drug-seeking in rats. In vivo microdialysis assays indicated that BCP alone did not produce a significant reduction in extracellular dopamine (DA) in the nucleus accumbens (NAc), while BCP pretreatment significantly reduced METH-induced increases in extracellular NAc DA in a dose-dependent manner, suggesting a DA-dependent mechanism involved in BCP action. Together, the present findings suggest that BCP might be a promising therapeutic candidate for the treatment of METH use disorder.

Dexmedetomidine Ameliorates Lung Injury Induced by Intestinal Ischemia/Reperfusion by Upregulating Cannabinoid Receptor 2, Followed by the Activation of the Phosphatidylinositol 3-Kinase/Akt Pathway.

Intestinal ischemia/reperfusion (I/R) is a clinical emergency, which often causes lung injury with high morbidity and mortality. Although dexmedetomidine has been identified to have a protective effect on lung injury caused by intestinal I/R, its specific mechanism is still elucidated. In recent years, the cannabinoid (CB2) receptor pathway has been found to be involved in I/R injury of some organs. In the current study, we investigated whether the CB2 receptor pathway contributes to the protective effect of dexmedetomidine on the intestinal I/R-induced lung injury in rats. Dexmedetomidine treatment upregulated the expression of CB2 receptor and suppressed the I/R-induced increases in lung injury scores, inflammatory cell infiltration, lung wet/dry ratio, MPO activity, MDA level, inflammatory cytokines, and caspase-3 expression while augmenting SOD activity and Bcl-2 expression, indicating attenuation of lung injury. Dexmedetomidine treatment also increased the expression of Akt. The protective effects of dexmedetomidine treatment were reversed by the CB2 receptor antagonist AM630 or the PI3K inhibitor wortmannin. And the CB2 receptor antagonist AM630 also downregulated the expression of Akt. Thus, our findings suggest that treatment with dexmedetomidine provides a protective role against lung injury caused by intestinal I/R in rats, possibly due to the upregulation of the CB2 receptor, followed by the activation of the PI3K/Akt pathway.

The HO-1-expressing bone mesenchymal stem cells protects intestine from ischemia and reperfusion injury.

BACKGROUND: Bone mesenchymal stromal cells (BMSC) showed protective potential against intestinal ischemia. Oxygenase-1(HO-1) could alleviate oxidative stress. In the present study, we constructed HO-1-expressing BMSC and detected the effects of it on survival, intestinal injury and inflammation following intestinal ischemia and reperfusion injury (I/R). METHODS: In this experiment, eighty adult male mice were divided into Sham, I/R, I/R + BMSC, I/R + BMSC/HO-1 groups. Mice were anesthetized and intestinal I/R model were established by temporarily occluding the superior mesenteric artery for 60 min with a non-crushing clamp. Following ischemia, the clamp was removed and the intestines were allowed for reperfusion. Prior to abdominal closure, BMSC/ HO-1 (2 × 106 cells) or BMSC (2 × 106 cells) were injected into the peritoneum of I/R mice respectively. Mice were allowed to recover for 24 h and then survival rate, intestinal injury and inflammation were determined. Reactive oxygen species (ROS) was assayed by fluorescent probe. TNFα and IL-6 were assayed by ELISA. RESULTS: BMSC/HO-1 increased seven day survival rate, improved intestinal injury and down-regulated inflammation after intestinal I/R when compared with sole BMSC (p < 0.05 respectively). Multiple pro-inflammatory media were also decreased following application of BMSC/HO-1, when compared with sole BMSC (p < 0.05) respectively, suggesting that BMSC /HO-1 had a better protection to intestinal I/R than BMSC therapy. CONCLUSION: Administration of BMSC/HO-1 following intestinal I/R, significantly improved intestinal I/R by limiting intestinal damage and inflammation.

The role of PI3K/Akt signal pathway in the protective effects of propofol on intestinal and lung injury induced by intestinal ischemia/reperfusion1.

PURPOSE: To investigate the role of PI3k/Akt signal pathway in the protective effects of propofol on intestinal and lung injury induced by intestinal ischemia/reperfusion(I/R). METHODS: Male Sprague-Dawley rats were subjected to 45 min of ischemia by occluding the superior mesenteric artery and to 2h of reperfusion to establish the model of I/R. Twenty four rats were randomly divided into four groups: Sham, intestinal I/R (II/R), propofol (P), wortmannin (W). In groups P, W, propofol was injected intravenously and continuously at the onset of reperfusion via infusion pump. PI3K inhibitor (wortmannin) was administered intravenously in group W 25 min before ischemia. Intestinal tissues and lung tissues were obtained for determination of histologic injury, wet/dry weight ratio, malondialdehyde (MDA) levels, superoxide dismutase (SOD) and myeloperoxidase (MPO) activities. Meanwhile, the expressions of caspase-3 and phosphorylated Akt (p-Akt) in intestines and lungs were detected by western blot. RESULTS: Propofol treatment alleviated intestinal and lung morphological changes which were observed in II/R group，Moreover, wet/dry weight ratio, the MDA level, MPO activity and expression of caspase-3 were significantly decreased whereas the SOD activity and p-Akt expression were significantly increased. Notably, the protections were significantly reversed by pretreatment of wortmannin. CONCLUSION: PI3K/Akt pathway activation play a critical role in the protective effects of propofol on intestinal and lung injury induced by ischemia/reperfusion.

SP1, MYC, CTNNB1, CREB1, JUN genes as potential therapy targets for neuropathic pain of brain.

Neuropathic pain (NP) may cause serious brain diseases, but the genes associated with the metabolic pathway and transcript factors of NP remain unclear. This study is aimed to identify the therapy target genes for NP and to investigate the metabolic pathways and transcript factors associated with NP. The differentially expressed genes of three brain tissues (nucleus accumbens, periaqueductal gray, and prefrontal cortex) dealt with NP stimulation were analyzed. Besides, The Database for Annotation, Visualization, and Integrated Discovery and Tfacts datasets were used in the analysis of the genes related to the metabolic pathway and transcript factors of the brain. Eight genes were found to coexpress in all three tissues. A functional enrichment analysis showed that the upregulated genes were mostly enriched in pathways as inflammatory response, calcium-mediated signaling, cytokine-cytokine receptor interaction, and extracellular matrix (ECM)-receptor interaction, whereas the downregulated genes were mostly enriched in pathways as phospholipid metabolic processes, positive regulation of protein kinase B signaling, and metabolism of xenobiotics by cytochrome P450. Finally, 135 and 98 transcript factors genes were upregulated and downregulated, among which SP1, MYC, CTNNB1, CREB1, JUN were identified as the most critical genes because the number of up- and downregulated gene ranked at the top. In conclusion, the pathways of immune response and cytokine-cytokine receptor interaction were determined as the main metabolic pathways of NP affecting the brain, and SP1, MYC, CTNNB1, CREB1, JUN genes were recognized as the most enriched genes in this process, which may provide evidence for the diagnosis and treatment research of neuropathic pain.

Cannabinoid CB1 receptor neutral antagonist AM4113 inhibits heroin self-administration without depressive side effects in rats.

Cannabinoid CB1 receptors (CB1Rs) have been shown to be a promising target in medication development for the treatment of addiction. However, clinical trials with SR141716A (rimonabant, a selective CB1R antagonist/inverse agonist) for the treatment of obesity and smoking cessation failed due to unwanted side effects, such as depression, anxiety, and suicidal tendencies. Recent preclinical studies suggest that the neutral CB1R antagonist AM4113 may retain the therapeutic anti-addictive effects of SR141716A in nicotine self-administration models and possibly has fewer unwanted side effects. However, little is known about whether AM4113 is also effective for other drugs of abuse, such as opioids and psychostimulants, and whether it produces depressive side effects similar to SR141716A in experimental animals. In this study, we demonstrated that systemic administration of AM4113 (3 and 10 mg/kg) dose-dependently inhibited the self-administration of intravenous heroin but not cocaine or methamphetamine, whereas SR141716A (3 and 10 mg/kg) dose-dependently inhibited the self-administration of heroin and methamphetamine but not cocaine. In the electrical brain-stimulation reward (BSR) paradigm, SR141716A (3 and 10 mg/kg) dose-dependently increased the BSR stimulation threshold (i.e., decreased the stimulation reward), but AM4113 had no effect on BSR at the same doses, suggesting that SR141716A may produce aversive effects while AM4113 may not. Together, these findings show that neutral CB1R antagonists such as AM4113 deserve further research as a new class of CB1R-based medications for the treatment of opioid addiction without SR141716A-like aversive effects.

The role of PI3K/Akt signal pathway in the protective effects of propofol on intestinal and lung injury induced by intestinal ischemia/reperfusion

Abstract Purpose: To investigate the role of PI3k/Akt signal pathway in the protective effects of propofol on intestinal and lung injury induced by intestinal ischemia/reperfusion(I/R). Methods: Male Sprague-Dawley rats were subjected to 45 min of ischemia by occluding the superior mesenteric artery and to 2h of reperfusion to establish the model of I/R. Twenty four rats were randomly divided into four groups: Sham, intestinal I/R (II/R), propofol (P), wortmannin (W). In groups P, W, propofol was injected intravenously and continuously at the onset of reperfusion via infusion pump. PI3K inhibitor (wortmannin) was administered intravenously in group W 25 min before ischemia. Intestinal tissues and lung tissues were obtained for determination of histologic injury, wet/dry weight ratio, malondialdehyde (MDA) levels, superoxide dismutase (SOD) and myeloperoxidase (MPO) activities. Meanwhile, the expressions of caspase-3 and phosphorylated Akt (p-Akt) in intestines and lungs were detected by western blot. Results: Propofol treatment alleviated intestinal and lung morphological changes which were observed in II/R group，Moreover, wet/dry weight ratio, the MDA level, MPO activity and expression of caspase-3 were significantly decreased whereas the SOD activity and p-Akt expression were significantly increased. Notably, the protections were significantly reversed by pretreatment of wortmannin. Conclusion: PI3K/Akt pathway activation play a critical role in the protective effects of propofol on intestinal and lung injury induced by ischemia/reperfusion.

Genetic deletion of the dopamine D3 receptor increases vulnerability to heroin in mice.

Despite extensive research, the neurobiological risk factors that convey vulnerability to opioid abuse are still unknown. Recent studies suggest that the dopamine D3 receptor (D3R) is involved in opioid self-administration, but it remains unclear whether altered D3R availability is a risk factor for the development of opioid abuse and addiction. Here we used dopamine D3 receptor-knockout (D3-KO) mice to investigate the role of this receptor in the different phases of opioid addiction. D3-KO mice learned to self-administer heroin faster and took more heroin than wild-type mice during acquisition and maintenance of self-administration. D3R-KO mice also displayed higher motivation to work to obtain heroin reward during self-administration under progressive-ratio reinforcement, as well as elevated heroin-seeking during extinction and reinstatement testing. In addition, deletion of the D3R induced higher baseline levels of extracellular dopamine (DA) in the nucleus accumbens (NAc), higher basal levels of locomotion, and reduced NAc DA and locomotor responses to lower doses of heroin. These findings suggest that the D3R is critically involved in regulatory processes that normally limit opioid intake via DA-related mechanisms. Deletion of D3R augments opioid-taking and opioid-seeking behaviors. Therefore, low D3R availability in the brain may represent a risk factor for the development of opioid abuse and addiction.

Transduced PEP-1-Heme Oxygenase-1 Fusion Protein Attenuates Lung Injury in Septic Shock Rats.

Oxidative stress and inflammation have been identified to play a vital role in the pathogenesis of lung injury induced by septic shock. Heme oxygenase-1 (HO-1), an effective antioxidant and anti-inflammatory and antiapoptotic substance, has been used for the treatment of heart, lung, and liver diseases. Thus, we postulated that administration of exogenous HO-1 protein transduced by cell-penetrating peptide PEP-1 has a protective role against septic shock-induced lung injury. Septic shock produced by cecal ligation and puncture caused severe lung damage, manifested in the increase in the lung wet/dry ratio, oxidative stress, inflammation, and apoptosis. However, these changes were reversed by treatment with the PEP-1-HO-1 fusion protein, whereas lung injury in septic shock rats was alleviated. Furthermore, the septic shock upregulated the expression of Toll-like receptor 4 (TLR4) and transcription factor NF-κB, accompanied by the increase of lung injury. Administration of PEP-1-HO-1 fusion protein reversed septic shock-induced lung injury by downregulating the expression of TLR4 and NF-κB. Our study indicates that treatment with HO-1 protein transduced by PEP-1 confers protection against septic shock-induced lung injury by its antioxidant, anti-inflammatory, and antiapoptotic effects.

XIST accelerates neuropathic pain progression through regulation of miR-150 and ZEB1 in CCI rat models.

LncRNAs are reported to participate in neuropathic pain development. LncRNA X-inactive specific transcript (XIST) is involved in the progression of various cancers. However, the role of XIST in neuropathic pain remains unclear. In our present study, we established a chronic constriction injury (CCI) rat model and XIST was found to be greatly upregulated both in the spinal cord tissues and in the isolated microglias of CCI rats. Inhibition of XIST inhibited neuropathic pain behaviors including mechanical and thermal hyperalgesia. Moreover, decrease of XIST repressed neuroinflammation through inhibiting COX-2, tumor necrosis factor (TNF)-α and IL-6 and in CCI rats. Previously, miR-150 has been reported to restrain neuropathic pain by targeting TLR5. Currently, miR-150 was predicted to be a microRNA target of XIST, which indicated a negative correlation between miR-150 and XIST. miR-150 was remarkably decreased in CCI rats and overexpression of miR-150 can significantly suppress neuroinflammation-related cytokines. Furthermore, ZEB1 was exhibited to be a direct target of miR-150 and we found it was overexpressed in CCI rats. Silencing ZEB1 was able to inhibit neuropathic pain in vivo and downreguation of XIST decreased ZEB1, which can be reversed by miR-150 inhibitors. Taken these together, we indicated that XIST can induce neuropathic pain development in CCI rats via upregulating ZEB1 by acting as a sponge of miR-150. It was revealed that XIST/miR-150/ZEB1 axis can be provided as a therapeutic target in neuropathic pain.

RETRACTED: LncRNA MALAT1 regulates sepsis-induced cardiac inflammation and dysfunction via interaction with miR-125b and p38 MAPK/NFκB.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief as there are concerns about the reliability of the results included in the article. The journal was initially contacted by the corresponding author to request the retraction of the article. Given the comments of Dr Elisabeth Bik regarding this article "This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern …", the journal requested the author to provide the raw data. However, the author was not able to fulfil this request.

Inhibition of miR-200b/miR-429 contributes to neuropathic pain development through targeting zinc finger E box binding protein-1.

Many studies have reported that microRNAs participate in neuropathic pain development. Previously, miR-200b and miR-429 are reported to be involved in various diseases. In our current study, we focused on their roles in neuropathic pain and we found that miR-200b and miR-429 were significantly decreased in chronic constriction injury (CCI) rat spinal cords and isolated microglials. miR-200b and miR-429 overexpression were able to relieve neuropathic pain through modulating PWT and PWL in CCI rats. Meanwhile, we observed that both miR-200b and miR-429 upregulation could repress neuroinflammation via inhibiting inflammatory cytokines such as IL-6, IL-1ß, and TNF-α in CCI rats. By carry out bioinformatics technology, Zinc finger E box binding protein-1 (ZEB1) was predicted as target of miR-200b, and miR-429 and dual-luciferase reporter assays confirmed the correlation between them. ZEB1 has been reported to regulate a lot of diseases. Here, we found that ZEB1 was greatly increased in CCI rats and miR-200b and miR-429 overexpression markedly suppressed ZEB1 mRNA expression in rat microglial cells. In addition, knockdown of ZEB1 can reduce neuropathic pain development and co-transfection of LV-anti-miR-200b/miR-429 reversed this phenomenon in vivo. Taken these together, our results suggested that miR-200b/miR-429 can serve as an important regulator of neuropathic pain development by targeting ZEB1.

HO-1 Overexpressed Mesenchymal Stem Cells Ameliorate Sepsis-Associated Acute Kidney Injury by Activating JAK/stat3 Pathway.

BACKGROUND: Stem cell therapy has been increasingly used in the treatment of sepsis-associated acute kidney injury (AKI). Engineering stem cells, through genetic method, for optimized therapeutic outcome is a desirable strategy, which requires clear understanding of molecular mechanism underlying the interaction between stem cells and damaged kidney. The aim of this study is to evaluate the therapeutic effects of HO-1 overexpressed mesenchymal stem cells (MSCs) in AKI and investigate the role of JAK/stat3 pathway in the treatment strategy. METHOD: HO-1 was overexpressed in human MSCs with transfection of the expression plasmid. Quantitative RT-PCR was used to validate HO-1 overexpression. Sepsis was induced by the Cecal ligation and puncture (CLP) in mice. Survival of the treated mice were monitored and compared to that of the untreated mice. Biochemical analysis of serum biomarkers including colony forming unit (CFU), Creatinine (Cr) and blood urea nitrogen (BUN) was acquired and acute tubular necrosis (ATN) was measured. The extent of kidney injury was assessed through H&E staining of the kidney sections. Inflammatory factors were also compared between the two groups. Western blot was used to analyze the role of JAK/stat3 signaling pathway in this treatment strategy. RESULTS: MSCs with HO-1 overexpression markedly improved the survival of the AKI mice, accompanied by decreasing of CFU, Cr BUN in serum and ATN scores. H&E staining validated that kidney tissue demonstrated morphology that was similar to normal kidney in HO-1 MSC treated group. Inflammatory factors were also reduced by HO-1 MSC treatment. Western blot analysis indicated an upregulation of key proteins in the JAK/stat3 pathway. CONCLUSIONS: HO-1 overexpression enhances therapeutic effect of MSCs in AKI, which is presumably attributed to the activation of JAK/stat3 signaling pathway.

Dexmedetomidine alleviates lipopolysaccharide-induced lung injury in Wistar rats.

This study aimed to investigate the protective effects of dexmedetomidine on lipopolysaccharide (LPS)-induced lung injury in Wistar rats. 24 female Wistar rats were randomly assigned into 3 groups (n = 8): a control group, a LPS-challenged group, and a LPS plus dexmedetomidine group. Inflammation, oxidative stress, Nrf2/Keap1, and Akt signal were determined. The results showed that LPS caused inflammation and oxidative stress via increasing pro-inflammatory cytokines and oxidative products. Dexmedetomidine treatment alleviated inflammation and oxidative stress in LPS-challenged rats. Nrf2/Keap1 was inhibited and Akt signal was activated in the lung after exposure to LPS, while dexmedetomidine activated Nrf2/Keap1, which further mediated expressions of antioxidant genes. In conclusion, dexmedetomidine alleviated inflammatory response and oxidative stress in LPS-induced lung injury in rats via influencing Nrf2/Keap1 signal.

HO-1 Protects against Hypoxia/Reoxygenation-Induced Mitochondrial Dysfunction in H9c2 Cardiomyocytes.

BACKGROUND: Mitochondrial dysfunction would ultimately lead to myocardial cell apoptosis and death during ischemia-reperfusion injuries. Autophagy could ameliorate mitochondrial dysfunction by autophagosome forming, which is a catabolic process to preserve the mitochondrial's structural and functional integrity. HO-1 induction and expression are important protective mechanisms. This study in order to investigate the role of HO-1 during mitochondrial damage and its mechanism. METHODS AND RESULTS: The H9c2 cardiomyocyte cell line were incubated by hypoxic and then reoxygenated for the indicated time (2, 6, 12, 18, and 24 h). Cell viability was tested with CCK-8 kit. The expression of endogenous HO-1(RT-PCR and Western blot) increased with the duration of reoxygenation and reached maximum levels after 2 hours of H/R; thereafter, the expression gradually decreased to a stable level. Mitochondrial dysfunction (Flow cytometry quantified the ROS generation and JC-1 staining) and autophagy (The Confocal microscopy measured the autophagy. RFP-GFP-LC3 double-labeled adenovirus was used for testing.) were induced after 6 hours of H/R. Then, genetic engineering technology was employed to construct an Lv-HO1-H9c2 cell line. When HO-1 was overexpressed, the LC3II levels were significantly increased after reoxygenation, p62 protein expression was significantly decreased, the level of autophagy was unchanged, the mitochondrial membrane potential was significantly increased, and the mitochondrial ROS level was significantly decreased. Furthermore, when the HO-1 inhibitor ZnPP was applied the level of autophagy after reoxygenation was significantly inhibited, and no significant improvement in mitochondrial dysfunction was observed. CONCLUSIONS: During myocardial hypoxia-reoxygenation injury, HO-1 overexpression induces autophagy to protect the stability of the mitochondrial membrane and reduce the amount of mitochondrial oxidation products, thereby exerting a protective effect.

EFFECT OF INTRAPERITONEAL RESUSCITATION WITH DIFFERENT CONCENTRATIONS OF SODIUM PYRUVATE ON INTESTINAL ISCHEMIA REPERFUSION INJURY IN HEMORRHAGIC SHOCK RAT.

OBJECTIVE: To determine the effects of intraperitoneal resuscitation (PR) with different concentrations of sodium pyruvate (PY) on intestinal ischemia reperfusion injury in rats hemorrhagic shock (HS). METHODS: Sixty rats were randomly assigned to six groups. These included: group SHAM, intravenous resuscitation only (VR) group, and four PR groups based on resuscitation fluid: glucose-lactate-based peritoneal dialysis solution (LA), and PY-1.1%, PY-1.6%, and PY-2.2% (concentrations in grams/dL). Mean arterial pressure (MAP) was monitored continuously. Blood pH, base excess (BE), lactate, intestinal myeloperoxidase (MPO), malondialdehyde (MDA), tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), activated caspase-3, and zonula occludens-1 (ZO-1) were measured; intestinal mucosal damage index (IMDI) and subcellular changes were observed; apoptotic index (AI) was calculated. RESULTS: Three hours after resuscitation, in PY groups, MPO, MDA, IMDI, AI, TNF-alpha, and IL-6 were significantly lower than VR and LA groups, while pH and BE were higher. PY groups showed less expression of activated caspase-3 but elevated ZO-1. Among PY groups, group PY-1.1% had the lowest MPO, MDA and TNF-alpha, and had less pathological damage and subcellular changes than other experimental groups. CONCLUSIONS: PR using PY solution combined with VR provided protection against intestinal ischemia-reperfusion injury following HS and resuscitation. Under the same hypertonic condition, 1.1% PY solution showed significant advantages compared with 2.2% and 1.6% solutions. The underlying mechanisms may include the maintenance of hemodynamic stability, regulation of homeostasis, inhibition of oxidative stress and inflammation, and protection of intestinal epithelial tight junction barrier function.