Protective effects of Nrf2 against sepsis-induced hepatic injury

Berberine alleviates fructose-induced hepatic injury via ADK/AMPK/Nrf2 pathway: A novel insight

Berberine (BBR) is a major active component of traditional Chinese medicine Rhizoma Coptidis and Cortex Phellodendri, which have been frequently used to treat liver diseases. Oxidative stress and inflammation are two pivotal hepatic pathological hallmarks. This study aimed to explore the potential effect and underlying mechanism of BBR on fructose-induced rat liver injury model, and hepatocyte damage in HepG2 and BRL-3A cells. Our results indicated that BBR effectively reversed fructose-induced body weight gain, glucose intolerance, and insulin resistance, observably attenuated abnormal histopathological alterations and ameliorated serum activities of ALT and AST. In vivo and in vitro, BBR significantly alleviated the secretion of pro-inflammatory cytokines IL-6 and TNF-α, and elevated levels of anti-inflammatory cytokine IL-10. BBR also attenuated oxidative stress by markedly decreasing intracellular contents of ROS and MDA, and increasing SOD enzymatic activity and GSH level. Furthermore, BBR substantially upregulated the protein expression of Nrf2, HO-1 and p-AMPK, and the fluorescence level of p-AMPK. In addition, BBR significantly increased the level of AMP, the ratio of AMP/ATP, and promoted the expression of ADK. Nevertheless, siADK abolished the benefits exerted by BBR on HepG2 and BRL-3A cells. Conclusively, the hepatoprotective effect of BBR was believed to be intimately associated with anti-inflammatory and antioxidant action mediated, at least partially, via ADK/AMPK/Nrf2 signaling. This work provided further support for the traditional application of Rhizoma Coptidis and Cortex Phellodendri in liver protection and might shed novel dimension to the clinical application of BBR, providing a promising lead compound for drug design.

Lipid Fraction from Agaricus brasiliensis as a Potential Therapeutic Agent for Lethal Sepsis in Mice

Sepsis is a potentially fatal clinical condition that results from an immune imbalance in the host during an infection. It presents systemic alterations due to excessive activation of pro-inflammatory mediators that contribute to inflammation, formation of reactive species, and tissue damage. Anti-inflammatory mediators are then extensively activated to regulate this process, leading to immune exhaustion and, consequently, immunosuppression of the host. Considering the biological activities of the nutraceutical Agaricus brasiliensis (A. brasiliensis), such as immunomodulatory, antioxidant, and antitumor activities, the present study investigated the therapeutic potential of the lipid fraction of A. brasiliensis (LF) in a model of lethal sepsis in mice (Mus musculus), induced by cecal ligation and perforation (CLP). The results showed that treatment of septic animals with LF or LF associated with ertapenem (LF-Erta) reduced systemic inflammation, promoting improvement in clinical parameters and increased survival. The data show a reduction in pro-inflammatory and oxidative stress markers, regulation of the anti-inflammatory response and oxidizing agents, and increased bacterial clearance in the peritoneal cavity and liver. Thus, it can be concluded that LF as a treatment, and in conjunction with antibiotic therapy, has shown promising effects as a hepatoprotective, antioxidant, antimicrobial, and immunomodulatory agent.

The beneficial effects of Rosuvastatin in inhibiting inflammation in sepsis

Microbial infection-induced sepsis causes excessive inflammatory response and multiple organ failure. An effective strategy for the treatment of sepsis-related syndromes is still needed. Rosuvastatin, a typical β-hydroxy β-methylglutaryl-CoA reductase inhibitor licensed for reducing the levels of low-density lipoprotein cholesterol in patients with hyperlipidemia, has displayed anti-inflammatory capacity in different types of organs and tissues. However, its effects on the development of sepsis are less reported. Here, we found that the administration of Rosuvastatin reduced the mortality of sepsis mice and prevented body temperature loss. Additionally, it inhibited the production of inflammatory cytokines such as tumor necrosis factor (TNF-α), Interleukin-6 (IL-6), interleukin-1β (IL-1β), and migration inhibitory factor (MIF) in peritoneal lavage supernatants of animals. The increased number of mononuclear cells in the peritoneum of sepsis mice was reduced by Rosuvastatin. Interestingly, it ameliorated lung inflammation and improved the hepatic and renal function in the sepsis animals. Further in vitro experiments show that Rosuvastatin inhibited lipopolysaccharide (LPS)-induced production of proinflammatory cytokines in RAW 264.7 macrophages by preventing the activation of nuclear factor kappa-B (NF-κB). Our findings demonstrate that the administration of Rosuvastatin hampered organ dysfunction and mitigated inflammation in a relevant model of sepsis.

Liensinine alleviates sepsis-induced acute liver injury by inhibiting the NF-κB and MAPK pathways in an Nrf2-dependent manner

Sepsis remains a serious public health issue that needs to be addressed globally. Severe liver injury caused by sepsis increases the risk of death in patients with sepsis. Liensinine (Lie) is one of the primary active components in Plumula nelumbinis and has anti-inflammatory and antioxidant effects. Nevertheless, the effects of Lie on septic liver injury are unclear. This research investigated the protective effect of Lie (10, 20 and 40 mg/kg) on liver damage via intraperitoneal administration of LPS (10 mg/kg) to C57BL/6 mice. Lie was given through intraperitoneal injection once a day for five days. Mice were treated with LPS intraperitoneally for 6 h at 1 h after Lie administration on the last day. The results suggested that Lie could decrease AST and ALT levels in serum, ameliorate histopathological changes and inhibit cell apoptosis in mice with LPS-induced septic liver injury. In addition, Lie inhibited increases in the mRNA levels of TNF-α, IL-1β, iNOS and IL-6. Lie also increased the mRNA level of IL-10. Lie reduced the content of MDA, a marker of lipid peroxidation, and increased the activity of the antioxidant enzymes GSH-Px, CAT and SOD. Our results also showed that Lie could suppress the LPS-activated MAPK and NF-κB pathways and trigger the Nrf2 signaling pathway both in vitro and in vivo. Additionally, an Nrf2 inhibitor (ML385) weakened the suppressive effect of Lie on the MAPK and NF-κB pathways. Our results demonstrated that the suppressive effect of Lie on the MAPK and NF-κB pathways was partially reliant on activation of the Nrf2 pathway. In summary, these results indicate that Lie can improve inflammation and oxidative stress by activating Nrf2, which is a prospective therapeutic drug for alleviating septic liver injury.

Gypenoside XLIX attenuates sepsis-induced splenic injury through inhibiting inflammation and oxidative stress

BACKGROUND

To investigate the effect of Gypenoside XLIX (Gyp-XLIX) on acute splenic injury (ASI) induced by cecal ligation and puncture (CLP) in septic mice, a study was conducted.

METHODS

Sixty healthy mice were randomly divided into six groups: the NC group, the Sham group, the Sham + Gyp-XLIX group, the CLP group, the CLP + Gyp-XLIX group, and the CLP + Dexamethasone (DEX) group. The NC group did not undergo any operation, while the rest of the groups underwent CLP to establish the sepsis model. The Sham group only underwent open-abdominal suture surgery without cecum puncture. After the operation, the groups were immediately administered the drug for a total of 5 days. Various methods such as hematoxylin and eosin (HE) staining, biochemical kits, qRT-PCR, and reactive oxygen species (ROS) were used for analysis.

RESULTS

The results demonstrated that Gyp-XLIX effectively mitigated the splenic histopathological damage, while reducing the malondialdehyde (MDA) lipid peroxidation index and enhancing the antioxidant activities of catalase (CAT), glutathione (GSH) and total antioxidant capacity (T-AOC). The utilization of Dihydroethidium (DHE) fluorescent probe revealed that Gyp-XLIX inhibited the acute splenic accumulation of ROS induced by CLP in septic mice. Further investigations revealed that Gyp-XLIX exhibited a down-regulatory effect on the protein levels of inflammatory mediators iNOS and COX-2, consequently leading to the suppression of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β. Additionally, it up-regulated the expression of anti-inflammatory factor IL-10.

CONCLUSION

In conclusion, Gyp-XLIX was significantly effective in attenuating CLP-induced acute splenic inflammation and oxidative stress in septic mice.

Abamectin causes cardiac dysfunction in carp via inhibiting redox equilibrium and resulting in immune inflammatory response and programmed cell death

This study aims to investigate the effects of environmentally relevant concentrations of abamectin on the cardiac function of carp and the potential mechanisms. Here, male carp were exposed to abamectin, and cardiac function-related enzymatic markers were examined. Cardiac histopathology, redox equilibrium, inflammation, and cell death were evaluated. Abamectin exposure caused cardiac dysfunction by upregulating lactate dehydrogenase (LDH), aspartate aminotransferase (AST), creatine kinase (CK), creatine Kinase MB isoenzyme (CK-MB) and white blood cells (WBCs), and decreasing red blood cells (RBCs) and hemoglobin (Hb). DHE staining and biochemical assays revealed that abamectin caused ROS release and oxidative stress by inhibiting Nrf2-ARE pathway. Histopathological and real-time fluorescence quantitative PCR (RT-qPCR) assays revealed that abamectin caused myocardial fiber swelling and inflammatory cell infiltration, enhanced pro-inflammatory cytokines tumor necrosis factor-α (Tnf-α), interleukin-1 beta (Il-1β), and Il-6 levels and attenuated anti-inflammatory cytokines Il-10 and transforming growth factor beta 1 (Tgf-β1) through activating NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome and nuclear factor kappa-B (NF-κB) pathway. Tunel staining showed that abamectin triggered cardiac apoptosis via activating p53-mediated mitochondrial apoptosis with elevated bcl2-associated X (Bax), reduced B-cell lymphoma-2 (Bcl-2), and activated Caspase-9 and Caspase-3. Immunoblot analysis revealed that abamectin activated autophagic flow by inhibiting mammalian target of rapamycin (mTOR), resulting in the conversion of LC3B from LC3-I to LC3-II, elevation of autophagy protein 5 (Atg5), and reduction of p62. Overall, abamectin caused cardiac dysfunction in carp via inhibiting redox equilibrium and resulting in immune inflammatory response and programmed cell death.

Maackiain protects against sepsis via activating AMPK/Nrf2/HO-1 pathway

Sepsis is a life-threatening medical condition caused by infection-triggered aberrant immune responses, leading to host tissue and organ injury. Despite advances in medical interventions, the mortality rate for septic shock remains high. Recent studies highlight the role of oxidative stress in the occurrence and development of sepsis, providing a potential therapeutic target for preventing sepsis-associated organ injury. In this study, we showed that Maackiain, a natural compound isolated from Sophora flavescens, exerted a protective role in a cecal ligation and puncture (CLP)-induced murine model of sepsis. Maackiain treatment reduced organ injury, and mitigated systematic inflammation and oxidative stress in septic mice. Maackiain also reduced the levels of inflammatory cytokines and reactive oxygen species (ROS) in RAW264.7 macrophage cells stimulated with lipopolysaccharide (LPS). We further demonstrated that Maackiain initiated activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in RAW264.7 cells in an AMP-activated protein kinase (AMPK)-dependent way. Moreover, inhibition of AMPK/Nrf2 axis abrogated the anti-inflammatory and anti-oxidant effects of Maackiain both in vitro and in vivo. Collectively, our study indicates that Maackiain treatment inhibits inflammatory response and oxidative stress via activation of AMPK/Nrf2/HO-1 pathway, thus exerting a protective effect against sepsis, providing an alternative option for sepsis prevention.