Resveratrol preconditioning protects hepatocytes against hepatic ischemia reperfusion injury via Toll-like receptor 4/nuclear factor-κB signaling pathway in vitro and in vivo

Targeting NF-κB in Hepatic Ischemia-Reperfusion Alleviation: from Signaling Networks to Therapeutic Targeting

Hepatic ischemia-reperfusion injury (HIRI) is a major complication of liver trauma, resection, and transplantation that can lead to liver dysfunction and failure. Scholars have proposed a variety of liver protection methods aimed at reducing ischemia-reperfusion damage, but there is still a lack of effective treatment methods, which urgently needs to find new effective treatment methods for patients. Many studies have reported that signaling pathway plays a key role in HIRI pathological process and liver function recovery mechanism, among which nuclear transfer factor-κB (NF-κB) signaling pathway is one of the signal transduction closely related to disease. NF-κB pathway is closely related to HIRI pathologic process, and inhibition of this pathway can delay oxidative stress, inflammatory response, cell death, and mitochondrial dysfunction. In addition, NF-κB can also interact with PI3K/Akt, MAPK, and Nrf2 signaling pathways to participate in HIRI regulation. Based on the role of NF-κB pathway in HIRI, it may be a potential target pathway for HIRI. This review emphasizes the role of inhibiting the NF-κB signaling pathway in oxidative stress, inflammatory response, cell death, and mitochondrial dysfunction in HIRI, as well as the effects of related drugs or inhibitors targeting NF-κB on HIRI. The objective of this review is to elucidate the role and mechanism of NF-κB pathway in HIRI, emphasize the important role of NF-κB pathway in the prevention and treatment of HIRI, and provide a theoretical basis for the target NF-κB pathway as a therapy for HIRI.

Network pharmacology and molecular docking elucidate potential mechanisms of Eucommia ulmoides in hepatic ischemia-reperfusion injury

Eucommia ulmoides (EU) and its diverse extracts have demonstrated antioxidative, anti-inflammatory, and cytoprotective properties against hepatic ischemia-reperfusion injury (HIRI). However, the primary constituents of EU and their putative mechanisms remain elusive. This study aims to explore the potential mechanisms of EU in the prevention and treatment of HIRI by employing network pharmacology and molecular docking methodologies. The main components and corresponding protein targets of EU were searched in the literature and TCMSP, and the compound target network was constructed by Cytoscape 3.9.1. Liver ischemia-reperfusion injury targets were searched in OMIM and GeneCards databases. The intersection points of compound targets and disease targets were obtained, and the overlapping targets were imported into the STRING database to construct the PPI network. We further analyzed the targets for GO and KEGG enrichment. Finally, molecular docking studies were performed on the core targets and active compounds. The component-target network unveiled a total of 26 efficacious bioactive compounds corresponding to 207 target proteins. Notably, the top-ranking compounds based on degree centrality were quercetin, β-sitosterol, and gallic acid. Within the PPI network, the highest degree centrality encompassed RELA, AKT1, TP53. GO and KEGG enrichment analysis elucidated that EU in HIRI primarily engaged in positive regulation of gene expression, positive transcriptional regulation via RNA polymerase II promoter, negative modulation of apoptotic processes, positive regulation of transcription from DNA templates, and drug responsiveness, among other biological processes. Key pathways included cancer pathways, RAGE signaling pathway, lipid metabolism, atherosclerosis, TNF signaling pathway, PI3K-Akt signaling pathway, and apoptotic pathways. Molecular docking analysis revealed robust affinities between quercetin, β-sitosterol, gallic acid, and RELA, AKT1, TP53, respectively. This study reveals EU exhibits substantial potential in mitigating and treating HIRI through multifaceted targeting and involvement in intricate signaling pathways.

The Protective Effect of Nutraceuticals on Hepatic Ischemia-Reperfusion Injury in Wistar Rats

Nutraceuticals are bioactive compounds present in foods, utilized to ameliorate health, prevent diseases, and support the proper functioning of the human body. They have gained attention due to their ability to hit multiple targets and act as antioxidants, anti-inflammatory agents, and modulators of immune response and cell death. Therefore, nutraceuticals are being studied to prevent and treat liver ischemia-reperfusion injury (IRI). This study evaluated the effect of a nutraceutical solution formed by resveratrol, quercetin, omega-3 fatty acid, selenium, ginger, avocado, leucine, and niacin on liver IRI. IRI was performed with 60 min of ischemia and 4 h of reperfusion in male Wistar rats. Afterward, the animals were euthanized to study hepatocellular injury, cytokines, oxidative stress, gene expression of apoptosis-related genes, TNF-α and caspase-3 proteins, and histology. Our results show that the nutraceutical solution was able to decrease apoptosis and histologic injury. The suggested mechanisms of action are a reduction in gene expression and the caspase-3 protein and a reduction in the TNF-α protein in liver tissue. The nutraceutical solution was unable to decrease transaminases and cytokines. These findings suggest that the nutraceuticals used favored the protection of hepatocytes, and their combination represents a promising therapeutic proposal against liver IRI.

Targeting Oxidative Stress with Polyphenols to Fight Liver Diseases

Reactive oxygen species (ROS) are important second messengers in many metabolic processes and signaling pathways. Disruption of the balance between ROS generation and antioxidant defenses results in the overproduction of ROS and subsequent oxidative damage to biomolecules and cellular components that disturb cellular function. Oxidative stress contributes to the initiation and progression of many liver pathologies such as ischemia-reperfusion injury (LIRI), non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC). Therefore, controlling ROS production is an attractive therapeutic strategy in relation to their treatment. In recent years, increasing evidence has supported the therapeutic effects of polyphenols on liver injury via the regulation of ROS levels. In the current review, we summarize the effects of polyphenols, such as quercetin, resveratrol, and curcumin, on oxidative damage during conditions that induce liver injury, such as LIRI, NAFLD, and HCC.

TRIM37 exacerbates hepatic ischemia/reperfusion injury by facilitating IKKγ translocation

BACKGROUND

Hepatic ischemia/reperfusion (I/R) injury is one of the major pathological processes associated with various liver surgeries. However, there is still a lack of strategies to protect against hepatic I/R injury because of the unknown underlying mechanism. The present study aimed to identify a potential strategy and provide a fundamental experimental basis for treating hepatic I/R injury.

METHOD

A classic 70% ischemia/reperfusion injury was established. Immunoprecipitation was used to identify direct interactions between proteins. The expression of proteins from different subcellular localizations was detected by Western blotting. Cell translocation was directly observed by immunofluorescence. HE, TUNEL and ELISA were performed for function tests.

RESULT

We report that tripartite motif containing 37 (TRIM37) aggravates hepatic I/R injury through the reinforcement of IKK-induced inflammation following dual patterns. Mechanistically, TRIM37 directly interacts with tumor necrosis factor receptor-associated factor 6 (TRAF6), inducing K63 ubiquitination and eventually leading to the phosphorylation of IKKβ. TRIM37 enhances the translocation of IKKγ, a regulatory subunit of the IKK complex, from the nucleus to the cytoplasm, thereby stabilizing the cytoplasmic IKK complex and prolonging the duration of inflammation. Inhibition of IKK rescued the function of TRIM37 in vivo and in vitro.

CONCLUSION

Collectively, the present study discloses some potential function of TRIM37 in hepatic I/R injury. Targeting TRIM37 might be potential for treatment against hepatic I/R injury.Targeting TRIM37 might be a potential treatment strategy against hepatic I/R injury.

Resveratrol improves hepatic ischemia-reperfusion injury by inhibiting neutrophils via the ERK signaling pathway

Hepatic ischemia-reperfusion injury (HIRI) is the main complication and even mortality in the setting of hepatic surgery or transplantation. Inflammation, especially the neutrophil response, plays important roles during the process of HIRI. In this study, we found that resveratrol preintervention ameliorated IRI-induced hepatic injury and neutrophil inflammatory responses in the liver. Moreover, RNA-sequencing analysis showed that resveratrol inhibited the functions of neutrophils, such as survival, cell cycle, migration and chemotaxis, oxidative stress and secretion of proinflammatory cytokines. Resveratrol restrained oxidative stress and the inflammatory response of neutrophils via inhibition of endothelin 1 autocrine signaling by suppressing the ERK signaling pathway. These data provide more evidence for the immunomodulatory role of resveratrol and enrich our understanding of immune strategies to improve HIRI.

Research progress of lncRNA and miRNA in hepatic ischemia-reperfusion injury

BACKGROUND

Hepatic ischemia-reperfusion injury (HIRI) is a common complication of liver surgeries, such as hepatectomy and liver transplantation. In recent years, several non-coding RNAs (ncRNAs) including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been identified as factors involved in the pathological progression of HIRI. In this review, we summarized the latest research on lncRNAs, miRNAs and the lncRNA-miRNA regulatory networks in HIRI.

DATA SOURCES

The PubMed and Web of Science databases were searched for articles published up to December 2021 using the following keywords: "hepatic ischemia-reperfusion injury", "lncRNA", "long non-coding RNA", "miRNA" and "microRNA". The bibliography of the selected articles was manually screened to identify additional studies.

RESULTS

The mechanism of HIRI is complex, and involves multiple lncRNAs and miRNAs. The roles of lncRNAs such as AK139328, CCAT1, MALAT1, TUG1 and NEAT1 have been established in HIRI. In addition, numerous miRNAs are associated with apoptosis, autophagy, oxidative stress and cellular inflammation that accompany HIRI pathogenesis. Based on the literature, we conclude that four lncRNA-miRNA regulatory networks mediate the pathological progression of HIRI. Furthermore, the expression levels of some lncRNAs and miRNAs undergo significant changes during the progression of HIRI, and thus are potential prognostic markers and therapeutic targets.

CONCLUSIONS

Complex lncRNA-miRNA-mRNA networks regulate HIRI progression through mutual activation and antagonism. It is necessary to screen for more HIRI-associated lncRNAs and miRNAs in order to identify novel therapeutic targets.

Resveratrol promotes liver cell survival in mice liver-induced ischemia-reperfusion through unfolded protein response: a possible approach in liver transplantation

Background

Ischemia-reperfusion (I/R) of the liver is a multifactorial condition that happens during transplantation and surgery. The deleterious effects of I/R result from the acute production of reactive oxygen species (ROS), which can trigger immediate tissue damage and induce a series of destructive cellular responses, including apoptosis organ failure and inflammation. The production of ROS in the I/R process can damage the antioxidant system and cause liver damage. Resveratrol has been shown to have antioxidant properties in several investigations. Here, we address the therapeutic effect of resveratrol on I/R-induced liver injury by focusing on unfolded protein response (UPR) signaling pathway.

Methods

Five minutes before reperfusion, resveratrol was injected into the tail vein of mice. They were ischemic for 1 h and then re-perfused for 3 h before being slaughtered (I/R). The activity of liver enzymes and the expression levels of genes involved in the unfolded protein response pathway were used to measure the hepatic damage.

Results

Our results revealed that the low dose of resveratrol (0.02 and 0.2 mg/kg) post-ischemic treatment significantly reduced the ALT and AST levels. In addition, compared with the control group, the expression of UPR pathway genes GRP78, PERK, IRE1α, CHOP, and XBP1 was significantly reduced in the resveratrol group. In the mice that received lower doses of resveratrol (0.02 and 0.2 mg/kg), the histopathological changes induced by I/R were significantly improved; however, the highest dose (2 mg/kg) of resveratrol could not significantly protect and solve the I/R damage.

Conclusion

The findings of this study suggest that hepatic ischemia occurs after liver transplantation and that receiving low-dose resveratrol treatment before reperfusion may promote graft survival through inhibition of UPR arms, especially PERK and IRE1α.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-022-00611-4.

Resveratrol modulates Toxoplasma gondii infection induced liver injury by intervening in the HMGB1/TLR4/NF-κB signaling pathway

Toxoplasma gondii (T. gondii) is an obligate intracellular parasite that can cause liver diseases in the host, including hepatitis and hepatomegaly. High mobility group box 1 (HMGB1) is the main inflammatory mediator causing cell injury or necrosis. HMGB1 binds to toll like receptor 4 (TLR4), then activates the nuclear factor-κB (NF-κB) signaling pathway, which promotes the release of inflammatory factors. Our previous studies showed that HMGB1 mediated TLR4/NF-κB signaling pathway plays an important role in liver injury induced by T. gondii infection. Resveratrol (RSV) is a small polyphenol, which has anti-inflammatory, anti-cancer, anti-T. gondii effect. However, the effect of RSV on liver injury caused by T. gondii infection is unclear. This study used the RH strain tachyzoites of T. gondii to infect murine liver line, NCTC-1469 cells to establish an in vitro model and acute infection of mice for the in vivo model to explore the protective effect of RSV on liver injury induced by T. gondii infection. The results showed that RSV inhibited the proliferation of T. gondii in the liver, reduced the alanine aminotransferase/aspartate aminotransferase levels and pathological liver damage. Additionally, RSV inhibited the production of tumor necrosis factor-α, inducible nitric oxide synthase and HMGB1 by interfering with the TLR4/NF-κB signaling pathway. These results indicate that RSV can protect liver injury caused by T. gondii infection by intervening in the HMGB1/TLR4/NF-κB signaling pathway. This study will provide a theoretical basis for RSV treatment of T. gondii infection induced liver injury.

CMPK2 accelerates liver ischemia/reperfusion injury via the NLRP3 signaling pathway

Cytidine monophosphate kinase 2 (CMPK2) is a mitochondrial nucleotide monophosphate kinase which is important for the substrates of mitochondrial DNA synthesis and has been reported to participate in macrophage activation and the inflammatory response. The purpose of the present research was to determine the potential role of CMPK2 in hepatic ischemia/reperfusion (I/R) injury and to elucidate the underlying molecular mechanisms. The present study investigated the role of CMPK2 in regulating the NLRP3 pathway and liver dysfunction induced by hepatic I/R both in vivo and in vitro. It was revealed that hypoxia/reoxygenation (H/R) treatment enhanced the mRNA expression levels of CMPK2, NLRP3, IL-18, IL-1β and TNF-α in RAW 264.7 cells. The protein expression levels of IL-18, IL-1β and cleaved-caspase-1 were decreased following CMPK2 knockdown. Furthermore, the inhibition of AIM2 downregulated the expression level of IL-1β, IL-18 and cleaved-caspase-1 in the CMPK2 knockdown group followed by H/R treatment, while the inhibition of NLRP3 did not. CMPK2 deficiency also decreased alanine aminotransferase and aspartate aminotransferase expression in mice serum, as well as the pathological changes in the liver. Similarly, the release of IL-18 and IL-1β in mouse serum was also restrained with the decline of CMPK2. In conclusion, the results of the present study demonstrate that CMPK2 is indispensable for NLRP3 inflammasome activation, making CMPK2 an effective target to relieve the liver from I/R injury. In addition, the function of CMPK2 is closely associated with NLRP3 inflammasome activation, instead of AIM2.

Inhibition of microRNA-297 alleviates THLE-2 cell injury induced by hypoxia/reoxygenation by inhibiting NLRP3 inflammasome activation via SIRT3

It has been acknowledged that microRNAs (miRNAs/miRs) assume a critical role in hypoxia/reoxygenation (H/R)-induced hepatocyte injury. Therefore, cell experiments were performed in this study to investigate the mechanism of miR-297 in H/R-induced hepatocyte injury with the involvement of Sirtuin 3 (SIRT3) and NLRP3. Initially, THLE-2 cells were utilized for H/R challenge. After miR-297 antagomir and NLRP3 adenovirus vector delivery, THLE-2 cell proliferation and apoptosis were measured by MTT, EdU and TUNEL assays, respectively. Enzyme-linked immunosorbent assay was conducted to evaluate the levels of apoptosis-related indicators (Bax and Bcl-2) and inflammation-related indicators (IL-6 and IL-10), western blot analysis to detect NLRP3 and Cleaved Caspase-1 expression. The binding relation between miR-297 and SIRT3 was examined using dual-luciferase assay. The results showed that miR-297 antagomir repressed the apoptosis and inflammation induced by H/R treatment in THLE-2 cells. Mechanistically, miR-297 antagomir diminished the extent of IκBα and NF-κB phosphorylation and NLRP3 activation in H/R-induced THLE-2 cells by targeting SIRT3. Furthermore, NLRP3 overexpression normalized the promoting effects of miR-297 antagomir on proliferation and its inhibitory effects on apoptosis and inflammation in H/R-induced THLE-2 cells. In summary, our results elucidated that miR-297 antagomir repressed H/R-induced THLE-2 cell injury via SIRT3 promotion and NLRP3 inactivation.

The hepatoprotective potential of resveratrol in an experimental model of ruptured abdominal aortic aneurysm via oxidative stress and apoptosis

The mortality rate in ruptured abdominal aortic aneurysms can today be reduced through cardiovascular surgery. However, ischemia and reperfusion-induced tissue damage develop due to aortic cross-clamping applied during surgery. The present study aimed to reduce oxidative stress-induced hepatic damage resulting from ischemia and reperfusion due to aortic cross-clamping during surgery by means of resveratrol administration. Forty male Sprague-Dawley rats were randomly assigned into four groups: control (healthy), glycerol+ischemia/reperfusion (I/R) (sham), I/R, and I/R + Resveratrol. In all groups scheduled for I/R, 60 min of shock was followed by 60 min of ischemia. In the I/R + Resveratrol group, 10 mg/kg of resveratrol was administered 15 min before ischemia and immediately before reperfusion via the intraperitoneal route. In addition, 120 min of reperfusion was applied under anesthesia after ischemia in all groups. Intralobar and interlobar necrosis, vascular congestion, and edematous fields resulting from aortic occlusion were present. Liver tissue malondialdehyde (MDA) levels and cleaved caspase-3 positivity increased, while glutathione (GSH) levels decreased. However, resveratrol administration reduced intralobular and interlobar necrosis, vascular congestion and edematous fields, cleaved caspase-3 positivity, and MDA levels, and increased GSH levels. Our findings suggest that resveratrol is effective against aortic occlusion-induced liver injury by reducing oxidative stress and apoptosis.

Toxic Effects of Docosahexaenoic Acid Treatment in the Rat Liver BRL-3A Cell

The cytotoxicity of docosahexaenoic acid (DHA) on normal cells is still unclear. This study investigated the effects of DHA on the cytotoxicity and possible mechanism in the BRL-3A cell. The cultured rat liver BRL-3A cell line was treated with 50, 100 and 200 μM DHA for 24 h. The cell viability was increased in the 50 and 100 μM DHA treatments, but decreased in the 200 μM DHA treatment. The 50, 100 and 200 μM DHA treatments increased the proportion of the apoptotic cells, the levels of lactate dehydrogenase (LDH), alkaline phosphatase (AKP) and IL-6 in the supernatant, and the ratio of the phosphonated p38MAPK to the p38MAPK (p-p38/p38) protein in the cells. The expression of TGF beta-activated kinase 1 (TAK1), nuclear transcription factor-κB p65 (NF-κB p65) and the inhibitor of NF-κB alpha (IκBα) mRNA, and the ratio of the phosphonated IκBα (p-IκBα) to IκBα protein were increased in the 200 μM DHA treatment, while the ratio of phosphonated extracellular regulated protein kinases (p-ERK) to ERK protein was decreased in the 200 μM DHA treatment. These results indicate that DHA-treated (50, 100 and 200 μM) BRL-3A cells for 24 h promotes cell apoptosis and inflammatory response, and the p38 MAPK, ERK and NF-κB signal pathways were involved in mediating the apoptosis and inflammatory response.

Liver kinase B1 attenuates liver ischemia/reperfusion injury via inhibiting the NLRP3 inflammasome

Liver ischemia/reperfusion injury (IRI), a serious inflammatory response driven by innate immunity, occurs in liver surgeries such as liver resection and liver transplantation, leading to liver dysfunction, liver failure, and even rejection after transplantation. Liver kinase B1 (LKB1) plays a pivotal anti-inflammatory role in IRI. One of the most important factors involved in liver IRI is the aberrant activation of the nucleotide binding oligomerization domain like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome in Kupffer cells. However, the mechanisms underlying the effect of LKB1 on the NLRP3 inflammasome in liver IRI remain elusive. In this study, we found that the expression of LKB1 was decreased in liver IRI, while the NLRP3 inflammasome level was increased as shown, as revealed by RT-qPCR and western blot analysis. Furthermore, upregulation of LKB1 abrogated the expression of the NLRP3 inflammasome, which improved liver function and liver pathology in the liver IRI model in vivo. In vitro, overexpression of LKB1 inhibited the activation of NLRP3 inflammasome and nuclear factor-κB, while the inhibitory effect was reversed by silencing the expression of the forkhead box protein O1 in the RAW264.7 macrophage hypoxia/reoxygenation model. In conclusion, our results suggest that LKB1 exerts a protective effect against liver IRI by downregulating the NLRP3 inflammasome.

Synergistic anti-liver cancer effects of curcumin and total ginsenosides

BACKGROUND

Liver cancer is the sixth most frequently occurring cancer in the world and the fourth most common cause of cancer mortality. The pathogenesis of liver cancer is closely associated with inflammation and immune response in the tumor microenvironment. New therapeutic agents for liver cancer, which can control inflammation and restore cellular immunity, are required. Curcumin (Cur) is a natural anti-inflammatory drug, and total ginsenosides (TG) are a commonly used immunoregulatory drug. Of note, both Cur and TG have been shown to exert anti-liver cancer effects.

AIM

To determine the synergistic immunomodulatory and anti-inflammatory effects of Cur combined with TG in a mouse model of subcutaneous liver cancer.

METHODS

A subcutaneous liver cancer model was established in BALB/c mice by a subcutaneous injection of hepatoma cell line. Animals were treated with Cur (200 mg/kg per day), TG (104 mg/kg per day or 520 mg/kg per day), the combination of Cur (200 mg/kg per day) and TG (104 mg/kg per day or 520 mg/kg per day), or 5-fluorouracil combined with cisplatin as a positive control for 21 d. Tumor volume was measured and the protein expression of programmed cell death 1 and programmed cell death 1 ligand 1 (PD-L1), inflammatory indicators Toll like receptor 4 (TLR4) and nuclear factor-κB (NF-κB), and vascular growth-related factors nitric oxide synthases (iNOS) and matrix metalloproteinase 9 were analyzed by Western blot analysis. CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) were counted by flow cytometry.

RESULTS

The combination therapy of Cur and TG significantly inhibited the growth of liver cancer, as compared to vehicle-treated animals, and TG showed dose dependence. Cur combined with TG-520 markedly decreased the protein expression of PD-L1 (P < 0.0001), while CD4⁺CD25⁺Foxp3⁺ Tregs regulated by the PD-L1 signaling pathway exhibited a positive correlation with PD-L1. Cur combined with TG-520 also inhibited the cascade action mediated by NF-κB (P < 0.0001), thus inhibiting the TLR4/NF-κB signalling pathway (P = 0.0088, P < 0.0001), which is associated with inflammation and acts on PD-L1. It also inhibited the NF-κB-MMP9 signalling pathway (P < 0.0001), which is associated with tumor angiogenesis.

CONCLUSION

Cur combined with TG regulates immune escape through the PD-L1 pathway and inhibits liver cancer growth through NF-κB-mediated inflammation and angiogenesis.

Toll-like Receptors as a Novel Therapeutic Target for Natural Products Against Chronic Diseases

Toll-like receptors (TLR) are one among the initial responders of the immune system which participate in the activation inflammatory processes. Several different types of TLR such as TLR2, TLR4, TLR7 and TLR9 have been identified in various cell types, each having distinct ligands like lipids, lipoproteins, nucleic acids and proteins. Though its prime concern is xenobiotic defences, TLR signalling has also recognized as an activator of inflammation and associated development of chronic degenerative disorders (CDDs) including obesity, type 2 diabetes mellitus (T2DM), fatty liver disease, cardiovascular and neurodegenerative disorders as well as various types of cancers. Numerous drugs are in use to prevent these disorders, which specifically inhibit different pathways associated with the development of CDDs. Compared to these drug targets, inhibition of TLR, which specifically responsible for the inflammatory insults has proven to be a better drug target. Several natural products have emerged as inhibitors of CDDs, which specifically targets TLR signalling, among these, many are in the clinical trials. This review is intended to summarize the recent progress on TLR association with CDDs and to list possible use of natural products, their combinations and their synthetic derivative in the prevention of TLR-driven CDD development.

Inhibition of microRNA-128-3p alleviates liver ischaemia-reperfusion injury in mice through repressing the Rnd3/NF-B axis

Although liver ischaemia-reperfusion (I/R) injury remains the primary underlying reason for liver transplant failure or post-transplantation liver dysfunction, the underlying mechanism is still largely elusive. MicroRNAs (miRNA) are involved in multiple physiological and pathological processes, including inflammation. Here, we identified that the miR-128-3p/Rho family GTPase 3 (Rnd3)/NF-κB axis might play a critical role in liver I/R injury. Our results demonstrated that the level of miR-128-3p was negatively correlated with the Rnd3 level during liver I/R. Dual luciferase reporter assay results proved that Rnd3 mRNA was a direct target of miR-128-3p. Additionally, Western blotting and quantitative RT-PCR analyses revealed that knock-down of miR-128-3p could up-regulate Rnd3 mRNA and protein levels, thereby suppressing the NF-κB pathway through down-regulating NF-κB p65. Consequently, the serum levels of NF-κB-associated inflammatory factors and aspartate aminotransferase/alanine aminotransferase were decreased. Moreover, overexpression of Rnd3 could reverse the activation of NF-κB caused by miR-128-3p agomir during liver I/R injury. Overall, our study results suggest that repression of miR-128-3p can alleviate liver I/R injury through the miR-128-3p/Rnd3/NF-κB axis and may facilitate the development of novel protective approaches against liver I/R injury.

Inhibition of miR-450b-5p ameliorates hepatic ischemia/reperfusion injury via targeting CRYAB

Hepatic ischemia/reperfusion injury (IRI) is an unavoidable course in liver transplantation, during which the immune response of inflammation plays a leading part. MicroRNA-450b-5p (miR-450b-5p), which has been reported to participate in several inflammatory diseases, was investigated in this study. The purpose of this study is to identify the potential function of miR-450b-5p toward remission of hepatic IRI and elucidate the specific mechanism. Herein we found that expression of miR-450b-5p, interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), and IL-6 was stimulated in hepatic IRI. Inhibition of miR-450b-5p could remarkably alleviate mouse hepatic IRI and improve liver function measured by hematoxylin-eosin (HE) staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), and enzyme-linked immunosorbent assay (ELISA). We further assessed protein expression undergoing Western blot and immunofluorescence, and discovered that miR-450b-5p suppressed alpha B-crystallin (CRYAB), thus restraining the inhibitory κB kinase (IKK) β-mediated canonical nuclear factor-κB (NF-κB) signaling, instead of the noncanonical path guided by IKKα in hepatic IRI. In addition, we demonstrated CRYAB as an activator of M2 polarization through protein kinase B (Akt) 1/mammalian target of rapamycin (mTOR), thus resulting in relief of liver IRI. Combination treatment containing both paths revealed a better antidamage efficacy than adjusting either path alone, suggesting that the joint therapy might be a promising solution in hepatic IRI.

Aloin Preconditioning Attenuates Hepatic Ischemia/Reperfusion Injury via Inhibiting TLR4/MyD88/NF-κB Signal Pathway In Vivo and In Vitro

Background

Aloin exerts considerable protective effects in various disease models, and its effect on hepatic ischemia-reperfusion (HIR) injury remains unknown. This research is aimed at conducting an in-depth investigation of the antioxidant, anti-inflammatory, and antiapoptosis effects of aloin in HIR injury and explain the underlying molecular mechanisms.

Methods

In vivo, different concentrations of aloin were intraperitoneally injected 1 h before the establishment of the HIR model in male mice. The hepatic function, pathological status, oxidative stress, and inflammatory and apoptosis markers were measured. In vitro, aloin (AL, C₂₁H₂₂O₉) or lipopolysaccharide (LPS) was added to a culture of mouse primary hepatocytes before it underwent hypoxia/reoxygenation (H/R), and the apoptosis in the mouse primary hepatocytes was analyzed.

Results

We found that 20 mg/kg was the optimum concentration of aloin for mitigating I/R-induced liver tissue damage, characterized by decreased serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Aloin pretreatment substantially suppressed the generation of hepatic malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α), and IL-6 and enhanced the hepatic superoxide dismutase (SOD) activities as well as glutathione (GSH) and IL-10 levels in the liver tissue of I/R mice; this indicated that aloin ameliorated I/R-induced liver damage by reducing the oxidative stress and inflammatory response. Moreover, aloin inhibited hepatocyte apoptosis and inflammatory response that was caused by the upregulated expression of Bcl-2, the downregulated expression of cleaved caspase3(C-caspase3), Bax, Toll-like receptor 4 (TLR4), FADD, MyD88, TRAF6, phosphorylated IKKα/β (p-IKKα/β), and phosphorylated nuclear factor κB p65 (p-NF-κB p65).

The protective effects of salvianolic acid A against hepatic ischemia-reperfusion injury via inhibiting expression of toll-like receptor 4 in rats

INTRODUCTION

Ischemia-reperfusion injury (IRI) is a serious complication of hepatectomy and liver transplantation. The aim of this study was to evaluate the protective effects of salvianolic acid-A (Sal-A) against IRI-induced hepatocellular injury.

MATERIAL AND METHODS

Forty rats were randomly divided into the following four groups: (1) sham group, (2) IR group, (3) Sal-A(10) group and (4) Sal-A(20) group. After 90 min of ischemia and 6 h of reperfusion, serum alanine aminotransferease (ALT) and apartate aminotransferase (AST) levels were measured; the amounts of malondialdehyde (MDA) and superoxide dismutase (SOD) in the liver tissue were determined; the expression of Bcl-2 and caspase-3 was detected and the severity of apoptosis, inflammation and pathological alterations were evaluated. Also apoptosis and mRNA and protein levels of TLR4 (toll-like receptor 4) were tested.

RESULTS

The serum aminotransferases, hepatic MDA concentration, and apoptotic cells in the IR group were significantly higher than in the sham group (p < 0.01), whereas the Sal-A group values were lower than in the IR group (p < 0.05). Compared with the IR group, the Sal-A groups had significantly higher Bcl-2 expression and downregulated cleaved caspase-3 expression in liver tissue. Moreover, increased mRNA and protein levels of TLR4 in IR rats and Sal-A could improve the increased mRNA and protein levels of TLR4.

CONCLUSIONS

Sal-A had a synergistically protective effect on the liver tissue against IRI that might be due to decreased oxidative stress, inflammation, hepatocellular apoptosis and include, at least in part, the regulation of TLR4.

Protective Role of Hepatocyte Cyclooxygenase-2 Expression Against Liver Ischemia-Reperfusion Injury in Mice

Liver ischemia and reperfusion injury (IRI) remains a serious clinical problem affecting liver transplantation outcomes. IRI causes up to 10% of early organ failure and predisposes to chronic rejection. Cyclooxygenase-2 (COX-2) is involved in different liver diseases, but the significance of COX-2 in IRI is a matter of controversy. This study was designed to elucidate the role of COX-2 induction in hepatocytes against liver IRI. In the present work, hepatocyte-specific COX-2 transgenic mice (hCOX-2-Tg) and their wild-type (Wt) littermates were subjected to IRI. hCOX-2-Tg mice exhibited lower grades of necrosis and inflammation than Wt mice, in part by reduced hepatic recruitment and infiltration of neutrophils, with a concomitant decrease in serum levels of proinflammatory cytokines. Moreover, hCOX-2-Tg mice showed a significant attenuation of the IRI-induced increase in oxidative stress and hepatic apoptosis, an increase in autophagic flux, and a decrease in endoplasmic reticulum stress compared to Wt mice. Interestingly, ischemic preconditioning of Wt mice resembles the beneficial effects observed in hCOX-2-Tg mice against IRI due to a preconditioning-derived increase in endogenous COX-2, which is mainly localized in hepatocytes. Furthermore, measurement of prostaglandin E₂ (PGE₂ ) levels in plasma from patients who underwent liver transplantation revealed a significantly positive correlation of PGE₂ levels and graft function and an inverse correlation with the time of ischemia. Conclusion: These data support the view of a protective effect of hepatic COX-2 induction and the consequent rise of derived prostaglandins against IRI.

SIRT1-regulated HMGB1 release is partially involved in TLR4 signal transduction: A possible anti-neuroinflammatory mechanism of resveratrol in neonatal hypoxic-ischemic brain injury

Neonatal hypoxic-ischemic brain injury (HIBI) is a knotty disease that lacks appropriate treatment. Inflammation is an important contributor to brain damage, and microglia are responsible for eliciting early and pronounced inflammatory reactions in the immature brain after hypoxic-ischemic (HI) insult. Acetylated HMGB1 can be released from immune cells into the extracellular space, where it acts as a danger-associated molecular pattern molecule to activate TLR4 signalling-mediated inflammatory responses. Resveratrol has neuroprotective and anti-inflammatory effects against HIBI, but whether these effects involve the regulation of the TLR4 signalling pathway and whether HMGB1 participates in this process is still unclear. We investigated the anti-inflammatory effects of resveratrol in HIBI and the molecular mechanisms potentially involved in the effect. The in vivo and in vitro results indicated that the level of cytoplasmic HMGB1 in microglia increased after insult and that treating experimental animals or mouse BV2 microglial cells with resveratrol attenuated HI insult-induced neuroinflammation, which was characterized by improved behavioural defects, reduced microglial activation and TLR4/MyD88/NF-κB signalling, and attenuated primary neuronal damage; this was accompanied by the inhibition of HMGB1 nucleoplasmic transfer and extracellular release. EX527 pretreatment reversed these effects. In addition, co-immunoprecipitation confirmed that SIRT1 was directly involved in the HMGB1 acetylation process in BV2 cells after oxygen glucose deprivation. These data demonstrate that resveratrol plays a neuroprotective role in neonatal HIBI by activating SIRT1 to inhibit HMGB1/TLR4/MyD88/NF-κB signalling and subsequent neuroinflammatory responses.

Pseudophosphatase STYX promotes tumor growth and metastasis by inhibiting FBXW7 function in colorectal cancer

Serine/threonine/tyrosine interacting protein (STYX), a member of protein tyrosine phosphatases, has recently been reported as a potential oncogene. However, the role of STYX in colorectal cancer (CRC) remains unknown. In this study, we found that STYX was highly expressed in CRC tissues and closely correlated with tumor development and survival of CRC patients. In vitro studies showed that overexpression of STYX promoted proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) and inhibited apoptosis in CRC cells, while STYX knockdown had the opposite effects. Consistently, in vivo experiments showed that overexpression of STYX promoted tumor growth and lung metastasis. Mechanically, STYX bound to the F-box and WD repeat domain-containing7 (FBXW7) protein and inhibited its function. Co-regulation of STYX and FBXW7 expression reversed the biological changes mediated by regulation of STYX expression alone in CRC cells. Additionally, FBXW7 expression was negatively associated with STYX expression in CRC tissues, and low STYX levels accompanying high FBXW7 levels predicted favorable prognosis of CRC patients. In conclusion, our results suggest that STYX plays an oncogenic role by inhibiting FBXW7 and represents a potential therapeutic target and prognostic biomarker in CRC.

MicroRNA-125b protects liver from ischemia/reperfusion injury via inhibiting TRAF6 and NF-κB pathway

MicroRNA-125b (miR-125b), which was previously proved to be a potential immunomodulator in various disease, attenuated mouse hepatic ischemia/reperfusion (I/R) injury in this study. miR-125b was decreased in RAW 264.7 cells exposed to hypoxia/reoxygenation (H/R). The expression of IL-1β, IL-6 and TNF-α in both serum and supernate were reduced in miR-125b over-expression groups. The hepatic histopathological changes were reduced in miR-125b agomir groups. In the miR-125b antagomir groups, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly elevated compared with negative control (NC) groups. The protein expression of TNF receptor-associated factor 6 (TRAF6), IL-1β and the phosphorylation of p65 (p-p65) were suppressed by the up-regulation of miR-125b. Furthermore, the nuclear translocation of p-p65, measured by immunofluorescence, was enhanced by the miR-125b inhibitors. In conclusion, our study indicates that miR-125b protects liver from hepatic I/R injury via inhibiting TRAF6 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signal pathway.

New therapeutic strategy of hinokitiol in haemorrhagic shock-induced liver injury

Haemorrhagic shock and resuscitation (HS/R) may cause global ischaemia-reperfusion injury, which can result in systemic inflammation, multiorgan failure (particularly liver failure) and high mortality. Hinokitiol, a bioactive tropolone-related compound, exhibits antiplatelet and anti-inflammatory activities. Targeting inflammatory responses is a potential strategy for ameliorating hepatic injury during HS/R. Whether hinokitiol prevents hepatic injury during HS/R remains unclear. In the present study, we determined the role of hinokitiol following HS/R. The in vivo assays revealed that hinokitiol markedly attenuated HS/R-induced hepatic injury. Hinokitiol could inhibited NF-κB activation and IL-6 and TNF-α upregulation in liver tissues. Moreover, hinokitiol reduced caspase-3 activation, upregulated Bax and downregulated Bcl-2. These findings suggest that hinokitiol can ameliorate liver injury following HS/R, partly through suppression of inflammation and apoptosis. Furthermore, the in vitro data revealed that hinokitiol significantly reversed hypoxia/reoxygenation (H/R)-induced cell death and apoptosis in the primary hepatocytes. Hinokitiol prevented H/R-induced caspase-3 activation, PPAR cleavage, Bax overexpression and Bcl-2 downregulation. Moreover, hinokitiol attenuated H/R-stimulated NF-κB activation and reduced the levels of IL-6 and TNF-α mRNAs, suggesting that hinokitiol can protect hepatocytes from H/R injury. Collectively, our data suggest that hinokitiol attenuates liver injury following HS/R, partly through the inhibition of NF-κB activation.

Vildagliptin Attenuates Hepatic Ischemia/Reperfusion Injury via the TLR4/NF-κB Signaling Pathway

The Toll-like receptor-4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway is vital in the pathogenesis of hepatic ischemia/reperfusion (HIR) injury. Dipeptidyl peptidase-4 (DPP4) inhibitors exert protective effects on IR injury of the kidney, heart, and lung; however, their effect on the liver is still unknown. Thus, the purpose of this study was to examine whether pretreatment with vildagliptin (Vilda), a DPP4 inhibitor, produces hepatic protection against IR injury and to investigate its influence on TLR4/NF-κB signaling in a rat model. Thirty male Wistar rats were divided into 3 groups: the sham group: subjected to a sham operation and received normal saline; the HIR group: subjected to HIR and received normal saline; and the Vilda + HIR group: subjected to HIR with pretreatment of 10 mg/kg/day Vilda for 10 days intraperitoneally. Hepatic ischemia lasted for 45 minutes followed by 3-hour reperfusion; then blood and liver samples were collected for biochemical and histopathological examination. The HIR group produced a significant increase in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatic malondialdehyde (MDA), nitric oxide (NO), and tumor necrosis factor alpha (TNF-α) levels and a significant reduction in the hepatic catalase level in comparison to the sham group. Moreover, a significant upregulation of gene and protein expressions of TLR4, NF-κB, and high-mobility group box-1 (HMGB1) along with caspase-3 protein expression was observed in the HIR group when compared with the sham group. Histopathological examination of the liver from the HIR group showed necrosis, sinusoidal congestion, hemorrhage, and hepatocyte degeneration. Administration of Vilda ameliorated the biochemical and histopathological changes caused by HIR. Vildagliptin showed for the first time a hepatoprotective effect in HIR injury through downregulation of TLR4/NF-κB/HMGB1 and caspase-3 hepatic expressions.

Oxyresveratrol prevents lipopolysaccharide/d-galactosamine-induced acute liver injury in mice

Oxyresveratrol (Oxy) is a natural polyhydroxystilbene abundant in mulberry that has anti-inflammation and anti-oxidant activities. We evaluated the protective effect of Oxy in the context of the lipopolysaccharide and d-galactosamine (LPS/d-GalN) induced acute liver injury. Oxy restricted the development of histopathological changes, markedly reduced the activity of alanine transaminase (ALT) and aspartate transaminase (AST), which are indicators of impaired liver function. Oxy significantly regulated the contents of oxidative stress related enzymes and products, and inhibited expressions of inflammatory mediators and cytokines. Oxy treatment diminished the Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway in liver, activated the Kelch-like ECH-associated protein 1(Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, and increased expressions of heme oxygenase 1 (HO-1) and quinine oxidoreductase 1(NQO1). Pretreatment with Oxy decreased LPS/d-GalN stimulated hepatocyte apoptosis by efficaciously raising the B-cell lymphoma 2 (Bcl-2)/Bcl-2 associated X (Bax) ratio, inhibiting the expression and activation of caspases, and activating the phosphoinoside-3-kinase (PI3K)-Akt pathway. Our results demonstrate the hepatoprotective efficacy of Oxy. The protection is mainly due to the prevention of TLR4/NF-κB pathway activation, induced activation of Keap1-Nrf2 signaling pathway, and decreased hepatocyte apoptosis. Oxy warrants further study as a potential therapeutic agent candidate for the management of acute liver injury.

Polydatin attenuates d-galactose-induced liver and brain damage through its anti-oxidative, anti-inflammatory and anti-apoptotic effects in mice

Accumulating evidence has shown that chronic injection of d-galactose (d-gal) can mimic natural aging, with accompanying liver and brain injury. Oxidative stress and apoptosis play a vital role in the aging process. In this study, the antioxidant ability of polydatin (PD) was investigated using four established in vitro systems. An in vivo study was also conducted to investigate the possible protective effect of PD on d-gal-induced liver and brain damage. The results showed that PD had remarkable in vitro free radical scavenging activity on 2,2-diphenyl-1-picryl-hydrazyl (DPPH˙), 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS⁺˙) radical ions, and hydroxyl and superoxide anions. Results in vivo indicated that, in a group treated with d-gal plus PD, PD remarkably decreased the depression of body weight and organ indexes, reduced the levels of the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and alleviated alterations in liver and brain histopathology. PD also significantly decreased the level of MDA and elevated SOD, GSH-Px, CAT activity and T-AOC levels in the liver and brain. In addition, the levels of inflammatory mediators, such as TNF-α, IL-1β and IL-6 in serum were markedly reduced after PD treatment. Western blotting results revealed that PD treatment noticeably attenuated the d-gal-induced elevation of Bcl-2/Bax ratio and caspase-3 protein expression in liver and brain. Overall, our findings indicate that PD treatment could effectively attenuate d-gal-induced liver and brain damage, and the mechanism might be associated with decreasing the oxidative stress, inflammation and apoptosis caused by d-gal. PD holds good potential for further development into a promising pharmaceutical candidate for the treatment of age-associated diseases.

Liver X Receptors Activation Attenuates Ischemia Reperfusion Injury of Liver Graft in Rats

Purpose: Suppression of the Toll like receptor 4 (TLR4)-nuclear factor-κB (NF-κB) signaling was critical in protection against liver IRI. Previous studies revealed that Liver X receptors (LXRs) activation could antagonize TLR4-NF-κB signaling. The purpose of this study is to determine whether LXRs agonist GW3965 can suppress the TLR4-NF-κB signaling during liver transplantation and protect ischemia-reperfusion injury (IRI). Materials and Methods: Sprague Dawley (SD) rats were used to perform orthotropic liver transplantation. Donors were pretreatment with GW3965 (0.3 mg/kg) through caudal vein injection 30 min before the surgery. The followings were analyzed after transplantation: alanine aminotransferase (ALT), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) level in serum, ATP binding cassette transporter A1 (Abca1) expression, NF-κB transcriptional activity, apoptosis and histological injury. Results: GW3965 pretreatment significantly ameliorated the degree of IRI associated with the effects of upregulating Abca1 expression, inhibiting NF-κB transcriptional activity, and downregulating TNF-α and IL-6 level. Conclusion: LXRs activation attenuated hepatic IRI by preventing TLR4-NF-κB signaling.

Liver X receptors agonist promotes differentiation of rat bone marrow derived mesenchymal stem cells into dopaminergic neuron-like cells

Dopaminergic (DA) neurons derived from bone marrow derived mesenchymal stem cells (BMSCs) maybe a valuable source for cell replacement therapy in Parkinson disease. Recent studies showed that new functions of LXR and their ligands have been proposed to prevent PD in the adult nervous system. The present study was designed to observe the effect of liver X receptors (LXR) agonist on differentiation of rat BMSCs into DA neurons. Expressions of the neuronal markers (Tuj1 and Nestin), the specific marker of DA neurons (tyrosine hydroxylase, TH), LXR α and LXR β were measured by immunocytochemical assay and TH/Tuj1 positive cells were determined by quantitative cell count analyses. mRNA expressions of LXR α, LXR β, TH, DAT, Nurr1, Pitx3, En1 and Lmx1b were measured by qPCR. Compared with growth factors (GF) treated group, combined use of LXR and GF induced rat BMSCs to TH-expressing cells with 87.42% of efficiency in 6 days of period of induction. LXR agonist alone did not induce the differentiation. Compared with GF alone, combined use of LXR and GF increased expressions of LXR α and LXR β protein and mRNA and TH, DAT, Nurr1, and Pitx3 mRNA, decreased expressions of En1 and Lmx1b mRNA. Our experimental results indicated that LXR activation leads to improve induction efficiency and shorten induction period of rat BMSCs into DA neuron-like cells through regulating DA development-related genes expressions and that LXR can be considered as a candidate target for drug development to improve differentiation of BMSCs into DA neurons.

Curcumin protects against hepatic ischemia/reperfusion induced injury through inhibiting TLR4/NF-κB pathway

The TLR4/NF-κB pathway had important roles in hepatic ischemia/reperfusion (I/R) injury. In this study, we reported a protective effect of curcumin against hepatic I/R injury via TLR4/NF-κB pathway. Curcumin significantly inhibited cell apoptosis, and decreased levels of LDH and production of TNF-a, IL-1b, and IL-6 in the cell supernatant. In addition, curcumin ameliorated elevated TLR4 and NF-κB caused by hypoxia/reoxygenation stimulation in BRL-3A cells. In vivo assays revealed that curcumin reduce levels of ALT and AST, and reversed TLR4/NF-κB signaling pathway caused by hepatic I/R stimulation in liver tissues. These results suggested that curcumin ameliorates hepatic I/R injury, which may be mediated in part via the TLR4/NF-κB signaling pathway.

Nitrite enhances liver graft protection against cold ischemia reperfusion injury through a NOS independent pathway

Introduction: Nitrite has been found to protect liver graft from cold preservation injury. However, the cell signaling pathway involved in this protection remains unclear. Here, we attempt to clarify if the NOS pathway by using the NOS inhibitor, L-NAME (L-N^G-Nitroarginine methyl ester).

Animals and methods: Rat livers were conserved for 24 h at 4°C in (IGL-1) solution enriched or not with nitrite at 50 nM. In a third group, rats were pretreated with 50 mg/kg of L-NAME before their liver procurement and preservation in IGL-1 supplemented with nitrite (50 nM) and L-NAME (1 mM). After 24 h of cold storage, rat livers were ex-vivo perfused at 37°C during 2 h. Control livers were perfused without cold storage.

Results: Nitrite effectively protected the rat liver grafts from the onset of cold I/R injury. L-NAME treatment did not abolish the beneficial effects of nitrite. Liver damage, protein oxidation and lipid peroxidation remained at low levels in both nitrite-treated groups when compared to IGL-1 group. Antioxidant enzyme activities and functional parameters were unchanged after NOS inhibition.

Conclusion: Despite NOS inhibition by L-NAME, nitrite can still provide hepatic protection during cold I/R preservation. This suggests that nitrite acts through a NOS-independent pathway.

Resveratrol mitigates lipopolysaccharide-mediated acute inflammation in rats by inhibiting the TLR4/NF-κBp65/MAPKs signaling cascade

Resveratrol (RSV) is a natural compound exhibiting anti-inflammatory effect, but the anti-inflammatory mechanism has not been fully understood. This study is aimed to evaluate the anti-inflammatory activity and mechanism of RSV in lipopolysaccharides-induced rats’ model. The visceral wet/dry weight ratios and the changes of hematologic and biochemical indices indicated that LPS- stimulation mainly caused damages to liver and lung, while pretreatment with RSV could alleviate the lesions. The cytokine assays showed that RSV could markedly decrease the production of proinflammatory mediators and cytokines (IL-1, IL-1β, IL-6, NO, iNOS and COX-2), and increase the expression of anti-inflammatory mediator (IL-10). RSV could inhibit TLR4 signaling pathway by down-regulating the mRNA levels of MyD88 and TRAF6, and suppressing the TLR4 protein. RSV could inhibit the signaling cascades of NF-κBp65 and MAPKs through down-regulating the mRNA levels of IκBα, p38MAPK, JNK, ERK1, ERK2 and ERK5 in liver and lung, and suppressing the dynamic changes of proteins and phosphorylated proteins including IκBα, NF-κBp65, p38MAPK, JNK, ERK1/2 and ERK5 from tissue’s cytoplasm to nucleus. In conclusion, RSV possessed a therapeutic effect on LPS-induced inflammation in rats and the mechanism mainly attributed to suppressing the signaling cascades of NF-κBp65 and MAPKs by inhibiting the TLR4 signaling pathway.

Pre-conditions for eliminating mitochondrial dysfunction and maintaining liver function after hepatic ischaemia reperfusion

The liver, the largest organ with multiple synthesis and secretion functions in mammals, consists of hepatocytes and Kupffer, stem, endothelial, stellate and other parenchymal cells. Because of early and extensive contact with the external environment, hepatic ischaemia reperfusion (IR) may result in mitochondrial dysfunction, autophagy and apoptosis of cells and tissues under various pathological conditions. Because the liver requires a high oxygen supply to maintain normal detoxification and synthesis functions, it is extremely susceptible to ischaemia and subsequent reperfusion with blood. Consequently, hepatic IR leads to acute or chronic liver failure and significantly increases the total rate of morbidity and mortality through multiple regulatory mechanisms. An increasing number of studies indicate that mitochondrial structure and function are impaired after hepatic IR, but that the health of liver tissues or liver grafts can be effectively rescued by attenuation of mitochondrial dysfunction. In this review, we mainly focus on the subsequent therapeutic interventions related to the conservation of mitochondrial function involved in mitigating hepatic IR injury and the potential mechanisms of protection. Because mitochondria are abundant in liver tissue, clarification of the regulatory mechanisms between mitochondrial dysfunction and hepatic IR should shed light on clinical therapies for alleviating hepatic IR‐induced injury.

Anti-inflammatory effect of miltirone on inflammatory bowel disease via TLR4/NF-κB/IQGAP2 signaling pathway

Inflammatory bowel disease (IBD) is characterized by a radical imbalance in the activation of proinflammatory and anti-inflammatory signaling pathways in the gut. This study was conducted to evaluate the anti-inflammation effect of miltirone against IBD in vitro and in vivo, and try to explore the underlying mechanisms. Miltirone could extenuate the loss of colon length and weight caused by TNBS. Additionally, macroscopic scores and DAI were reduced significantly compared with the TNBS group. The levels of TNF-α, IL-1β, IL-6 and IL-8 were increased significantly with the induction by TNBS (100mg/kg) or LPS (0.5mg/mL). Interestingly, miltirone could down-regulate the levels of these increased pro-inflammatory factors in a dose-dependent manner both in vivo and in vitro. The protein and mRNA expressions of TLR4, MyD88, NF-κB p65 were up-regulated by TNBS or LPS stimulation. CRX-526, the TLR4 inhibitor, as well as miltirone could significantly suppress the increased protein and mRNA expressions. Miltirone could up-regulate the descreased IQGAP2 expression induced by LPS. All these revealed that the anti-inflammatory effect of miltirone on IBD may be via regulating TLR4/NF-κB/IQGAP2 signaling pathway. The findings might supply beneficial hints for the drug research to cure the IBD.