Embelin attenuates lipopolysaccharide-induced acute kidney injury through the inhibition of M1 macrophage activation and NF-κB signaling in mice

Modified Xi-Jiao-Di-Huang Decoction Alleviates Sepsis via Regulating Macrophage Polarization by Inhibiting the PIM2/NF-κB Pathway

Purpose

Modified Xi-Jiao-Di-Huang decoction (MXJDH) has significant clinical efficacy for the treatment of sepsis; however, its mechanism of action remains unclear. The purpose of this study was to investigate the protective effects of MXJDH in septic mice and explore its mechanism of action.

Methods

Utilizing UPLC-Q-TOF-MS, we identified the primary constituents of the compound MXJDH. Subsequently, we created a mouse model for sepsis, observing their overall condition, including specific symptoms and behavior. We also monitored key inflammatory markers and pathological changes in their organs. Flow cytometry was then employed to assess the polarization of macrophages. Transcriptome sequencing was used to identify genes with altered expression patterns. We investigated the connection between MXJDH and the Pim2/NF-κB signaling pathway, a crucial regulatory mechanism in inflammation. Finally, we examined the expression and tissue distribution of macrophages in the sepsis-induced mice.

Results

MXJDH effectively reduces inflammation in sepsis mice, leading to a progressive recovery of organ functions. Moreover, MXJDH facilitates the conversion of macrophages from pro-inflammatory M1 phenotype to anti-inflammatory M2 phenotype. This transformation is potentially mediated through the Pim2/NF-κB signaling pathway. By suppressing Pim2 expression, MXJDH mitigates the nuclear translocation of NF-κB, thereby modulating the expression of downstream inflammatory mediators. The role of MXJDH in regulating macrophage polarization has also been confirmed in sepsis mouse tissues.

Conclusion

MXJDH regulates macrophage polarization, inhibits CRS, and alleviates sepsis by inhibiting the Pim2/NF-κB signaling pathway.

Comparative Evaluation of Vasorelaxant and Antiplatelet Activity of Two Plant-Derived Benzoquinones: Rapanone and Embelin

Vasorelaxant and antiplatelet agents play an important role in preventing and combating endothelial dysfunction, atherosclerosis and a plethora of associated cardiovascular diseases (CVDs). CVDs are the leading cause of death worldwide and nowadays occur not only in developed but also in developing societies. They include, among others, coronary heart disease, cerebrovascular disease and peripheral artery disease. Due to their high prevalence, it is important to seek efficient preventive measures, such as lifestyle changes and the implementation of appropriate herbal dietary supplementation and treatment alternatives. Plant-derived quinones have recently drawn researchers' attention due to their interesting biological potential. Embelin and rapanone are two plant-derived benzoquinones with anti-inflammatory and antioxidant properties. Embelin has already been shown to have vasorelaxant and antiplatelet activity, but little is known about rapanone in the context of CVDs. Therefore, we decided to comparatively evaluate their activity in a specially designed experimental protocol. Following the isolation of both benzoquinones from plant sources (rapanone from Ardisia crenata leaves; embelin from Lysimachia punctata roots), their effects were comparatively assessed in a biofunctional study on isolated rat aorta (precontracted with phenylephrine) and in vitro on platelet aggregation. Both benzoquinones showed 50% vasorelaxation in an NO-dependent manner. Interestingly, rapanone was slightly more effective as an antiplatelet agent than embelin. The antiplatelet effect of both benzoquinones was specific, as no cytotoxicity towards platelets was observed at the concentrations tested. This is the first report on the vasorelaxant and antiplatelet activity of rapanone.

Ursodeoxycholic acid protects against sepsis-induced acute kidney injury by activating Nrf2/HO-1 and inhibiting NF-κB pathway

BACKGROUND

Ursodeoxycholic acid (UDCA), traditionally recognized for its hepatoprotective effects, has also shown potential in protecting kidney injury. This study aimed to evaluate the protective effects of UDCA against sepsis-induced acute kidney injury (AKI) and to elucidate the underlying mechanisms.

METHODS

Sixty male C57BL/6 N mice were utilized to establish a sepsis-induced AKI model through intravenous injection of lipopolysaccharides (LPS, 10 mg/kg). UDCA (15, 30, and 60 mg/kg) was administered intraperitoneally once daily for 7 days before LPS injection. Kidney injury was evaluated by HE staining and biochemical markers, including serum creatinine (Cr), blood urea nitrogen (BUN), urinary protein, neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), N-acetyl-β-D-glucosaminidase (NAG), and retinol binding protein (RBP). Oxidative stress parameters and nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase-1 (HO-1) pathway, pro-inflammatory cytokines and nuclear factor-kappa B (NF-κB) pathway were also evaluated. Additionally, HK-2 cells were treated with LPS in vitro, and cell viability and apoptosis were detected using CCK-8 kit and flow cytometer, respectively.

RESULTS

UDCA significantly attenuated LPS-induced renal histopathological damage and improved renal function, as evidenced by reduction in serum Cr, BUN, and urinary protein levels. UDCA also up-regulated the protein expression of zonula occludens-1 (ZO-1) and Ezrin in the kidney, and reduced the urinary levels of NGAL, KIM-1, NAG, and RBP. Moreover, UDCA inhibited NF-κB p65 phosphorylation and reduced pro-inflammatory cytokines levels (TNF-α, IL-1β, and IL-6) in both serum and kidney. UDCA alleviated oxidative stress by activating the Nrf2/HO-1 pathway in the kidney. In vitro, UDCA reduced LPS-induced cell injury and apoptosis in HK-2 cells, with these protective effects being blocked by the Nrf2 inhibitor ML385.

CONCLUSIONS

Our present study demonstrated that UDCA exerts protective effects against sepsis-induced AKI by attenuating oxidative stress and inflammation, primarily through the activation of the Nrf2/HO-1 pathway and inhibition of the NF-κB pathway. These findings highlight the therapeutic potential of UDCA in preventing sepsis-induced AKI.

Macrophage polarization in sepsis: Emerging role and clinical application prospect

Sepsis is a severe, potentially fatal condition defined by organ dysfunction due to excessive inflammation. Its complex pathogenesis and poor therapeutic outcomes pose significant challenges in treatment. Macrophages, with their high heterogeneity and plasticity, play crucial roles in both the innate and adaptive immune systems. They can polarize into M1-like macrophages, which promote pro-inflammatory responses, or M2-like macrophages, which mediate anti-inflammatory responses, positioning them as critical mediators in the immune response during sepsis.Macrophages are the main regulators of inflammatory responses, and their polarization is also regulated by inflammatory signaling pathways. This review highlights recent advances in the inflammatory signaling pathways involved in sepsis, mechanism of macrophage polarization mediated by inflammation-related signaling pathways in sepsis, and the role of signaling pathway mediated macrophage polarization in organ dysfunction involved in sepsis. We also explore the therapeutic potential of targeting macrophage polarization for immunotherapy, offering new perspectives on macrophage-targeted treatments for sepsis.

A Microenvironment-Responsive, Controlled Release Hydrogel Delivering Embelin to Promote Bone Repair of Periodontitis via Anti-Infection and Osteo-Immune Modulation

Periodontitis, a prevalent chronic inflammatory disease, poses significant challenges for effective treatment due to its complex etiology involving specific bacteria and the inflammatory immune microenvironment. Here, this study presents a novel approach for the targeted treatment of periodontitis utilizing the immunomodulatory and antibacterial properties of Embelin, a plant-derived compound, within an injectable hydrogel system. The developed Carboxymethyl Chitosan-Oxidized Dextran (CMCS-OD) hydrogel formed via dynamic chemical bonds exhibited self-healing capabilities and pH-responsive behavior, thereby facilitating the controlled release of Embelin and enhancing its efficacy in a dynamic oral periodontitis microenvironment. This study demonstrates that this hydrogel system effectively prevents bacterial invasion and mitigates excessive immune response activation. Moreover, it precisely modulates macrophage M1/M2 phenotypes and suppresses inflammatory cytokine expression, thereby fostering a conducive environment for bone regeneration and addressing periodontitis-induced bone loss. These findings highlight the potential of the approach as a promising strategy for the clinical management of periodontitis-induced bone destruction.

Exploring the efficacious constituents and underlying mechanisms of sini decoction for sepsis treatment through network pharmacology and multi-omics

BACKGROUND

Traditional Chinese medicine prescription sini decoction (SND) can alleviate inflammation, improve microcirculation, and modulate immune status in sepsis patients. However, its underlying mechanisms remain unclear, and therapeutic effects may vary among individuals.

PURPOSE

Through a comprehensive and systematic network pharmacology analysis, the purpose of this study is to investigate the therapeutic mechanisms of SND in treating sepsis.

METHODS

An analysis of WGCNA identified CX3CR1 as a key gene influencing sepsis prognosis. A drug-active component-target network for SND was created using the traditional Chinese medicine systems pharmacology (TCMSP) database and Cytoscape software. Shared targets between SND and CX3CR1 high-expression gene modules were found through the GEO database. Gene module functionality was analyzed using GO, KEGG, GSEA, and GSVA. Unsupervised clustering of sepsis patients was performed based on the ferroptosis gene set, and immune cell interactions and mechanisms were explored using CIBERSORT, single-cell sequencing, and intercellular communication analysis.

RESULTS

This study demonstrates that high expression of CX3CR1 improves survival rates in sepsis patients and is associated with immune cell signaling pathways. SND contains 116 active components involved in oxidative stress and lipid metabolism pathways. HMOX1, a co-expressed gene in SND and CX3CR1 high-expression gene module, plays a crucial role in sepsis survival. Unsupervised clustering analysis classified sepsis patients into three clusters based on the ferroptosis gene set, revealing differences in immune cell expression and involvement in heme metabolism pathways. Notably, intercellular interactions among immune cells primarily occur through paracrine and autocrine mechanisms in MIF, GALECTIN, and IL16 signaling pathways, modulating the immune-inflammatory microenvironment in sepsis.

CONCLUSIONS

This study identifies CX3CR1 as a crucial molecule impacting sepsis prognosis through WGCNA analysis. It reveals that SND's active component, quercetin and kaempferol, target HMOX1 via related pathways to regulate heme metabolism, reduce inflammation, inhibit ferroptosis, and improve immune function, ultimately improving sepsis prognosis. These findings offer a solid pharmacological foundation and potential therapeutic targets for SND in treating sepsis.

Protective Role of MAVS Signaling for Murine Lipopolysaccharide-Induced Acute Kidney Injury

Despite treatment advances, acute kidney injury (AKI)-related mortality rates are still high in hospitalized adults, often due to sepsis. Sepsis and AKI could synergistically worsen the outcomes of critically ill patients. TLR4 signaling and mitochondrial antiviral signaling protein (MAVS) signaling are innate immune responses essential in kidney diseases, but their involvement in sepsis-associated AKI (SA-AKI) remains unclear. We studied the role of MAVS in kidney injury related to the TLR4 signaling pathway using a murine LPS-induced AKI model in wild-type and MAVS-knockout mice. We confirmed the importance of M1 macrophage in SA-AKI through in vivo assessment of inflammatory responses. The TLR4 signaling pathway was upregulated in activated bone marrow-derived macrophages, in which MAVS helped maintain the LPS-suppressed TLR4 mRNA level. MAVS regulated redox homeostasis via NADPH oxidase Nox2 and mitochondrial reverse electron transport in macrophages to alleviate the TLR4 signaling response to LPS. Hypoxia-inducible factor 1α (HIF-1α) and AP-1 were key regulators of TLR4 transcription and connected MAVS-dependent reactive oxygen species signaling with the TLR4 pathway. Inhibition of succinate dehydrogenase could partly reduce inflammation in LPS-treated bone marrow-derived macrophages without MAVS. These findings highlight the renoprotective role of MAVS in LPS-induced AKI by regulating reactive oxygen species generation-related genes and maintaining redox balance. Controlling redox homeostasis through MAVS signaling may be a promising therapy for SA-AKI.