Margatoxin mitigates CCl4‑induced hepatic fibrosis in mice via macrophage polarization, cytokine secretion and STAT signaling

Unveiling the power of microenvironment in liver regeneration: an in-depth overview

The liver serves as a vital regulatory hub for various physiological processes, including sugar, protein, and fat metabolism, coagulation regulation, immune system maintenance, hormone inactivation, urea metabolism, and water-electrolyte acid-base balance control. These functions rely on coordinated communication among different liver cell types, particularly within the liver's fundamental hepatic lobular structure. In the early stages of liver development, diverse liver cells differentiate from stem cells in a carefully orchestrated manner. Despite its susceptibility to damage, the liver possesses a remarkable regenerative capacity, with the hepatic lobule serving as a secure environment for cell division and proliferation during liver regeneration. This regenerative process depends on a complex microenvironment, involving liver resident cells, circulating cells, secreted cytokines, extracellular matrix, and biological forces. While hepatocytes proliferate under varying injury conditions, their sources may vary. It is well-established that hepatocytes with regenerative potential are distributed throughout the hepatic lobules. However, a comprehensive spatiotemporal model of liver regeneration remains elusive, despite recent advancements in genomics, lineage tracing, and microscopic imaging. This review summarizes the spatial distribution of cell gene expression within the regenerative microenvironment and its impact on liver regeneration patterns. It offers valuable insights into understanding the complex process of liver regeneration.

Comparative Histological Study of Therapeutic Effect of Mesenchymal Stem Cells versus Mesenchymal Stem Cells Co-Cultured with Liver Tissue on Carbon Tetrachloride-Induced Hepatotoxicity in Adult Male Albino Rats

Context

Liver diseases are major causes of morbidity and mortality. Mesenchymal stem cells (MSCs) have immunomodulatory, anti-inflammatory, and antifibrotic effects, so they can be used in the treatment of liver diseases. MSCs co-cultured with diseased liver tissue improve the homing capacity, survival rate, and paracrine effects of the MSCs, as well as the ability to enhance liver function.

Aims

This work aimed to study the therapeutic effect of MSCs versus MSCs co-cultured with liver tissue on carbon tetrachloride (CCl4)-induced hepatotoxicity in adult male albino rats.

Settings and Design

Twenty adult male albino rats were divided into four equal groups; Group I (control group), Group II received CCl4 intraperitoneally (i.p.), Group III received CCl4 i.p. and then injected with MSCs intravenously (i.v.), and Group IV received CCl4 i.p. and then injected with co-cultured MSCs i.v.

Materials and Methods

Finally, liver specimens were processed for light microscopy (LM) and electron microscopy (EM). Statistical analysis was carried out to assess histological scoring, area percentage of collagen fibers, number of glial fibrillary acidic protein-positive cells, and biochemical analysis of alanine aminotransferase and aspartate aminotransferase.

Statistical Analysis Used

Statistical analysis of (histological scoring, area % of collagen fibers, and biochemical analysis) was done by using one-way analysis of variance (ANOVA) test using graphpad software (SanDiego, CA, USA). The means ± standard deviations were used for statistical analysis.

Results

LM of Group II revealed loss of hepatic architecture and diffuse fibrosis with dilated congested blood vessels, bile ductular proliferation, and cellular infiltrations. Vacuolated cytoplasm with or without pyknotic nuclei was observed in addition to micro- and macro-steatosis. EM demonstrated disfigured hepatocytes with abnormal organelles surrounding atypical nucleus. Group III showed restoration of the normal liver architecture with greater extent in Group IV. Statistical analysis confirmed the microscopic findings.

Conclusions

Co-cultured MSCs with diseased liver tissue augmented the therapeutic effects of MSCs in treating hepatotoxicity induced by CCl4 in adult male albino rats.

Aqueous extract of Amydrium sinense (Engl.) H. Li alleviates hepatic fibrosis by suppressing hepatic stellate cell activation through inhibiting Stat3 signaling

Background: The present study aimed to investigate the protective effect of the water extract of Amydrium sinense (Engl.) H. Li (ASWE) against hepatic fibrosis (HF) and clarify the underlying mechanism. Methods: The chemical components of ASWE were analysed by a Q-Orbitrap high-resolution mass spectrometer. In our study, an in vivo hepatic fibrosis mouse model was established via an intraperitoneal injection of olive oil containing 20% CCl₄. In vitro experiments were conducted using a hepatic stellate cell line (HSC-T6) and RAW 264.7 cell line. A CCK-8 assay was performed to assess the cell viability of HSC-T6 and RAW264.7 cells treated with ASWE. Immunofluorescence staining was used to examine the intracellular localization of signal transducer and activator of transcription 3 (Stat3). Stat3 was overexpressed to analyse the role of Stat3 in the effect of ASWE on HF. Results: Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that candidate targets of ASWE, associated with protective effects against hepatic fibrosis, were related to inflammation response. ASWE ameliorated CCl₄-induced liver pathological damage and reduced the liver index and alanine transaminase (ALT) and aspartate transaminase (AST) levels. ASWE also decreased the serum levels of collagen Ⅰ (Col Ⅰ) and hydroxyproline (Hyp) in CCl₄-treated mice. In addition, the expression of fibrosis markers, including α-SMA protein and Acta2, Col1a1, and Col3a1 mRNA, was downregulated by ASWE treatment in vivo. The expression of these fibrosis markers was also decreased by treatment with ASWE in HSC-T6 cells. Moreover, ASWE decreased the expression of inflammatory markers, including the Tnf-α, Il6 and Il1β, in RAW264.7 cells. ASWE decreased the phosphorylation of Stat3 and total Stat3 expression and reduced the mRNA expression of the Stat3 gene in vivo and in vitro. ASWE also inhibited the nuclear shuttling of Stat3. Overexpression of Stat3 weakened the therapeutic effect of ASWE and accelerated the progression of HF. Conclusion: The results show that ASWE protects against CCl₄-induced liver injury by suppressing fibrosis, inflammation, HSC activation and the Stat3 signaling pathway, which might lead to a new approach for preventing HF.

Current Status of Peptide Medications and the Position of Active Therapeutic Peptides with Scorpion Venom Origin

: Peptides are highly potent, selective, and relatively safe therapeutics. Over the past two decades, natural peptides have been obtained, studied, and eventually approved by the Food and Drug Administration (FDA) due to advancements in identification, production, modification, and analytical technologies. Some peptide therapeutics has been derived from the venom gland of venomous animals, including snake, leech, lizard, snail, and scorpion. Scorpion was identified as a reservoir of important peptides with pharmaceutical properties. The scorpion uses these peptides for capturing prey and defense. However, their pharmacological properties in treating different diseases, including cardiac problems, autoimmune and infectious diseases, and diverse cancers, have been confirmed. Ion channel modifiers are the greatest components of the scorpion venom glands. Due to advances in proteomic and transcriptomic approaches, the identification of new scorpion venom peptides is steadily increasing. In this review, we tried to represent the current status of peptide medicines and describe the last peptide medications approved by FDA in 2022. Moreover, we will further explain potent peptides originating from scorpion venom, which have gone through important steps to be approved.

Expression of O-glycosylated oncofetal fibronectin in alternatively activated human macrophages

Macrophage (Mϕ) polarization is an essential phenomenon for the maintenance of homeostasis and tissue repair, and represents the event by which Mϕ reach divergent functional phenotypes as a result to specific stimuli and/or microenvironmental signals. Mϕ can be polarized into two main phenotypes, M1 or classically activated and M2 or alternatively activated. These two categories diverge in many aspects, such as secreted cytokines, markers of cell surface, and biological functions. Over the last 10 years, many potential markers have been proposed for both M1 and M2 human Mϕ. However, there is scarce information regarding the glycophenotype adopted by these cells. Here, we show that M2- but not M1-polarized Mϕ expresses high levels of an unusual glycoform of fibronectin (FN), named O-glycosylated oncofetal FN (onf-FN), found in fetal/cancer cells, but not in healthy tissues. The onf-FN expression was confirmed in vitro by Western blot and real-time RT-qPCR in primary and cell line monocyte-derived Mϕ. onf-FN was induced by IL-4 and IL-13, but not by pro-inflammatory stimuli (LPS and INF-γ). RNA and protein analysis clearly demonstrated that it is specifically associated with the M2 polarization. In conclusion, we show by the first time that O-glycosylated onf-FN is expressed by M2-polarized Mϕ.

Age-related Changes in Trigeminal Ganglion Macrophages Enhance Orofacial Ectopic Pain After Inferior Alveolar Nerve Injury

BACKGROUND/AIM

The ectopic pain associated with inferior alveolar nerve (IAN) injury has been reported to involve macrophage expression in the trigeminal ganglion (TG). However, the effect of age-related changes on this abnormal pain conditions are still unknown. This study sought to clarify the involvement of age-related changes in macrophage expression and phenotypic conversion in the TG and how these changes enhance ectopic mechanical allodynia after IAN transection (IANX).

MATERIALS AND METHODS

We used senescence-accelerated mouse (SAM)-prone 8 (SAMP8) and SAM-resistance 1 (SAMR1) mice, which are commonly used to study ageing-related changes. Mechanical stimulation was applied to the whisker pad skin under light anaesthesia; the mechanical head withdrawal threshold (MHWT) was measured for 21 d post-IANX. We subsequently counted the numbers of Iba1 (macrophage marker)-immunoreactive (IR) cells, Iba1/CD11c (M1-like inflammatory macrophage marker)-co-IR cells, and Iba1/CD206 (M2-like anti-inflammatory macrophage marker)-co-IR cells in the TG innervating the whisker pad skin. After continuous intra-TG administration of liposomal clodronate Clophosome^®-A (LCCA) to IANX-treated SAMP8-mice, the MHWT values of the whisker pad skin were examined.

RESULTS

Five days post-IANX, the MHWT had significantly decreased in SAMP8 mice compared to SAMR1-mice. Iba1-IR and Iba1/CD11c-co-IR cell counts were significantly increased in SAMP8 mice compared to SAMR1 mice 5 d post-IANX. LCCA administration significantly restored MHWT compared to control-LCCA administration.

CONCLUSION

Ectopic mechanical allodynia of whisker pad skin after IANX is exacerbated by ageing, which involves increases in M1-like inflammatory macrophages in the TG.

Role of macrophages in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe cardiopulmonary vascular disease characterized by progressive pulmonary artery pressure elevation, increased pulmonary vascular resistance and ultimately right heart failure. Studies have demonstrated the involvement of multiple immune cells in the development of PAH in patients with PAH and in experimental PAH. Among them, macrophages, as the predominant inflammatory cells infiltrating around PAH lesions, play a crucial role in exacerbating pulmonary vascular remodeling in PAH. Macrophages are generally polarized into (classic) M1 and (alternative) M2 phenotypes, they accelerate the process of PAH by secreting various chemokines and growth factors (CX3CR1, PDGF). In this review we summarize the mechanisms of immune cell action in PAH, as well as the key factors that regulate the polarization of macrophages in different directions and their functional changes after polarization. We also summarize the effects of different microenvironments on macrophages in PAH. The insight into the interactions between macrophages and other cells, chemokines and growth factors may provide important clues for the development of new, safe and effective immune-targeted therapies for PAH.

Advances in the role of STAT3 in macrophage polarization

The physiological processes of cell growth, proliferation, differentiation, and apoptosis are closely related to STAT3, and it has been demonstrated that aberrant STAT3 expression has an impact on the onset and progression of a number of inflammatory immunological disorders, fibrotic diseases, and malignancies. In order to produce the necessary biological effects, macrophages (M0) can be polarized into pro-inflammatory (M1) and anti-inflammatory (M2) types in response to various microenvironmental stimuli. STAT3 signaling is involved in macrophage polarization, and the research of the effect of STAT3 on macrophage polarization has gained attention in recent years. In order to provide references for the treatment and investigation of disorders related to macrophage polarization, this review compiles the pertinent signaling pathways associated with STAT3 and macrophage polarization from many fundamental studies.

Antioxidant potential, cytokines regulation, and inflammation-related genes expression of phenolic extracts from Mexican oregano

The Mexican population traditionally uses oregano infusions to treat oxidative and inflammation-related disorders. Therefore, this study was focused on the examination of the antioxidant capacity and potential against inflammation from three Mexican oregano species (Lippia graveolens [LG], Lippia palmeri [LP], and Hedeoma patens [HP]). The extracts from LG showed a superior total phenolic content. LG, LP, and HP exhibited a higher capacity to inhibit the radical DPPH (up to 90.33 ± 0.25%) and significantly lowered the release of MCP-1 and IL-6. At the same time, LG and HP increased the secretion of IL-10. Extracts from LG, LP, and HP did not significantly diminish the expression of il-1β or inos, although a slight decrease in inos expression was observed. Our findings support that phenolic extracts from L. graveolens, L. palmeri, and H. patens possess antioxidant and anti-inflammatory properties and might be potential therapeutic candidates against oxidative and inflammation-related diseases. PRACTICAL APPLICATIONS: Oregano species have traditionally been exploited as remedies against inflammatory-related diseases, namely headaches, asthma, bowel disorders, and rheumatism. This study explored the antioxidant potential of three Mexican oregano species (Lippia graveolens, Lippia palmeri, and Hedeoma patens) and their anti-inflammatory effects in a murine cell model. Phenolic extracts from oregano showed antioxidant capacity and exerted activity against inflammation by improving anti-inflammatory cytokines secretion or negatively regulating pro-inflammatory cytokines. The results of our study demonstrate that the phenolic extracts from these Mexican oregano species have the potential in treating inflammation-related diseases.

Ameliorative Effect of Pomegranate Peel Extract (PPE) on Hepatotoxicity Prompted by Iron Oxide Nanoparticles (Fe2O3-NPs) in Mice

An evaluation of the ameliorative effect of pomegranate peel extract (PPE) in counteracting the toxicity of iron oxide nanoparticles (Fe₂O₃-NPs) that cause hepatic tissue damage is focused on herein. Forty male albino mice were haphazardly grouped into four groups as follows: the first control group was orally gavage daily with physiological saline; the second group received 100 mg/kg of PPE by the oral route day after day; the third group received 30 mg/kg Fe₂O₃-NPs orally; and the fourth group received both PPE and Fe₂O₃-NPs by the oral route, the same as the second and third sets. Later, after the completion of the experiment, we collected the liver, blood, and bone marrow of bone specimens that were obtained for further laboratory tests. For instance, exposure to Fe₂O₃-NPs significantly altered serum antioxidant biomarkers by decreasing the levels of total antioxidant capacity (TAC), catalase (CAT), and glutathione s-transferase (GST). Additionally, it caused changes in the morphology of hepatocytes, hepatic sinusoids, and inflammatory Kupffer cells. Furthermore, they significantly elevated the number of chromosomal aberrations including gaps, breaks, deletions, fragments, polyploidies, and ring chromosomes. Moreover, they caused a significant overexpression of TIMP-1, TNF-α, and BAX mRNA levels. Finally, the use of PPE alleviates the toxicity of Fe₂O₃-NPs that were induced in the hepatic tissues of mice. It is concluded that PPE extract has mitigative roles against the damage induced by Fe₂O₃-NPs, as it serves as an antioxidant and hepatoprotective agent. The use of PPE as a modulator of Fe₂O₃-NPs' hepatotoxicity could be considered as a pioneering method in the use of phytochemicals against the toxicity of nanoparticles.

Advances in the Regulation of Macrophage Polarization by Mesenchymal Stem Cells and Implications for ALI/ARDS Treatment

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a common condition with high mortality. ALI/ARDS is caused by multiple etiologies, and the main clinical manifestations are progressive dyspnea and intractable hypoxemia. Currently, supportive therapy is the main ALI/ARDS treatment, and there remains a lack of targeted and effective therapeutic strategies. Macrophages are important components of innate immunity. M1 macrophages are pro-inflammatory, while M2 macrophages are anti-inflammatory and promote tissue repair. Mesenchymal stem cells (MSCs) are stem cells with broad application prospects in tissue regeneration due to their multi-directional differentiation potential along with their anti-inflammatory and paracrine properties. MSCs can regulate the balance of M1/M2 macrophage polarization to improve the prognosis of ALI/ARDS. In this paper, we review the mechanisms by which MSCs regulate macrophage polarization and the signaling pathways associated with polarization. This review is expected to provide new targets for the treatment of ALI/ARDS.

MyD88 in hepatic stellate cells enhances liver fibrosis via promoting macrophage M1 polarization

During liver fibrosis, quiescent HSCs (qHSCs) are activated to become activated HSCs (aHSCs)/myofibroblasts. The signal adapter MyD88, an essential component of TLR signaling, plays an important role in liver fibrosis. However, far less is known about the specific effects of MyD88 signaling in both qHSCs and aHSCs in the progress of liver fibrosis. Here, we used a CCl₄-induced mouse fibrosis model in which MyD88 was selectively depleted in qHSCs (GFAP^MyD88−/− mice) or aHSCs (α-SMA^MyD88−/− mice). MyD88 deficiency in qHSCs or aHSCs attenuated liver fibrosis in mice and inhibited α-SMA-positive cell activation. Inhibition of MyD88 in HSCs decreased α-SMA and collagen I levels, inflammatory cell infiltration, and pro-inflammatory gene expression. Furthermore, MyD88 signaling in HSCs increased the secretion of CXCL10, which promoted macrophage M1 polarization through CXCR3, leading to activation of the JAK/STAT1 pathway. Inhibition of CXCL10 attenuated macrophage M1 polarization and reduced liver fibrosis. Thus, MyD88 signaling in HSCs crucially contributes to liver fibrosis and provides a promising therapeutic target for the prevention and treatment of liver fibrosis.

Macrophage Polarization and Its Role in Liver Disease

Macrophages are important immune cells in innate immunity, and have remarkable heterogeneity and polarization. Under pathological conditions, in addition to the resident macrophages, other macrophages are also recruited to the diseased tissues, and polarize to various phenotypes (mainly M1 and M2) under the stimulation of various factors in the microenvironment, thus playing different roles and functions. Liver diseases are hepatic pathological changes caused by a variety of pathogenic factors (viruses, alcohol, drugs, etc.), including acute liver injury, viral hepatitis, alcoholic liver disease, metabolic-associated fatty liver disease, liver fibrosis, and hepatocellular carcinoma. Recent studies have shown that macrophage polarization plays an important role in the initiation and development of liver diseases. However, because both macrophage polarization and the pathogenesis of liver diseases are complex, the role and mechanism of macrophage polarization in liver diseases need to be further clarified. Therefore, the origin of hepatic macrophages, and the phenotypes and mechanisms of macrophage polarization are reviewed first in this paper. It is found that macrophage polarization involves several molecular mechanisms, mainly including TLR4/NF-κB, JAK/STATs, TGF-β/Smads, PPARγ, Notch, and miRNA signaling pathways. In addition, this paper also expounds the role and mechanism of macrophage polarization in various liver diseases, which aims to provide references for further research of macrophage polarization in liver diseases, contributing to the therapeutic strategy of ameliorating liver diseases by modulating macrophage polarization.

Review on Biological Characteristics of Kv1.3 and Its Role in Liver Diseases

The liver accounts for the largest proportion of macrophages in all solid organs of the human body. Liver macrophages are mainly composed of cytolytic cells inherent in the liver and mononuclear macrophages recruited from the blood. Monocytes recruitment occurs mainly in the context of liver injury and inflammation and can be recruited into the liver and achieve a KC-like phenotype. During the immune response of the liver, macrophages/KC cells release inflammatory cytokines and infiltrate into the liver, which are considered to be the common mechanism of various liver diseases in the early stage. Meanwhile, macrophages/KC cells form an interaction network with other liver cells, which can affect the occurrence and progression of liver diseases. From the perspective of liver disease treatment, knowing the full spectrum of macrophage activation, the underlying molecular mechanisms, and their implication in either promoting liver disease progression or repairing injured liver tissue is highly relevant from a therapeutic point of view. Kv1.3 is a subtype of the voltage-dependent potassium channel, whose function is closely related to the regulation of immune cell function. At present, there are few studies on the relationship between Kv1.3 and liver diseases, and the application of its blockers as a potential treatment for liver diseases has not been reported. This manuscript reviewed the physiological characteristics of Kv1.3, the relationship between Kv1.3 and cell proliferation and apoptosis, and the role of Kv1.3 in a variety of liver diseases, so as to provide new ideas and strategies for the prevention and treatment of liver diseases. In short, by understanding the role of Kv1.3 in regulating the functions of immune cells such as macrophages, selective blockers of Kv1.3 or compounds with similar functions can be applied to alleviate the progression of liver diseases and provide new ideas for the prevention and treatment of liver diseases.

Pathophysiology and Treatment Options for Hepatic Fibrosis: Can It Be Completely Cured?

Hepatic fibrosis is a dynamic process that occurs as a wound healing response against liver injury. During fibrosis, crosstalk between parenchymal and non-parenchymal cells, activation of different immune cells and signaling pathways, as well as a release of several inflammatory mediators take place, resulting in inflammation. Excessive inflammation drives hepatic stellate cell (HSC) activation, which then encounters various morphological and functional changes before transforming into proliferative and extracellular matrix (ECM)-producing myofibroblasts. Finally, enormous ECM accumulation interferes with hepatic function and leads to liver failure. To overcome this condition, several therapeutic approaches have been developed to inhibit inflammatory responses, HSC proliferation and activation. Preclinical studies also suggest several targets for the development of anti-fibrotic therapies; however, very few advanced to clinical trials. The pathophysiology of hepatic fibrosis is extremely complex and requires comprehensive understanding to identify effective therapeutic targets; therefore, in this review, we focus on the various cellular and molecular mechanisms associated with the pathophysiology of hepatic fibrosis and discuss potential strategies to control or reverse the fibrosis.

Anti-inflammatory effects of FS48, the first potassium channel inhibitor from the salivary glands of the flea Xenopsylla cheopis

The voltage-gated potassium (Kv) 1.3 channel plays a crucial role in the immune responsiveness of T-lymphocytes and macrophages, presenting a potential target for treatment of immune- and inflammation related-diseases. FS48, a protein from the rodent flea Xenopsylla cheopis, shares the three disulfide bond feature of scorpion toxins. However, its three-dimensional structure and biological function are still unclear. In the present study, the structure of FS48 was evaluated by circular dichroism and homology modeling. We also described its in vitro ion channel activity using patch clamp recording and investigated its anti-inflammatory activity in LPS-induced Raw 264.7 macrophage cells and carrageenan-induced paw edema in mice. FS48 was found to adopt a common αββ structure and contain an atypical dyad motif. It dose-dependently exhibited the Kv1.3 channel in Raw 264.7 and HEK 293T cells, and its ability to block the channel pore was demonstrated by the kinetics of activation and competition binding with tetraethylammonium. FS48 also downregulated the secretion of proinflammatory molecules NO, IL-1β, TNF-α, and IL-6 by Raw 264.7 cells in a manner dependent on Kv1.3 channel blockage and the subsequent inactivation of the MAPK/NF-κB pathways. Finally, we observed that FS48 inhibited the paw edema formation, tissue myeloperoxidase activity, and inflammatory cell infiltrations in carrageenan-treated mice. We therefore conclude that FS48 identified from the flea saliva is a novel potassium channel inhibitor displaying anti-inflammatory activity. This discovery will promote understanding of the bloodsucking mechanism of the flea and provide a new template molecule for the design of Kv1.3 channel blockers.

Increased expression levels of inflammatory cytokines and adhesion molecules in lipopolysaccharide‑induced acute inflammatory apoM‑/‑ mice

Apolipoprotein M (apoM) may serve a protective role in the development of inflammation. Nuclear factor-κB (NF-κB) and its downstream factors (including a number of inflammatory cytokines and adhesion molecules) are essential for the regulation of inflammatory processes. In the present study, the importance of apoM in lipopolysaccharide (LPS)-induced acute inflammation and its potential underlying mechanisms, were investigated using an apoM-knockout mouse model. The levels of inducible nitric oxide synthase (iNOS), NF-κB, interleukin (IL)-1β, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion protein 1 (VCAM-1) were detected using reverse transcription-quantitative PCR and western blotting. The serum levels of IL-6 and IL-10 were detected using Luminex technology. The results demonstrated that the protein levels of iNOS, NF-κB, IL-1β, ICAM-1 and VCAM-1 were significantly increased in apoM^−/− mice compared with those in apoM^+/+ mice. In addition, two-way ANOVA revealed that the interaction between apoM and LPS had a statistically significant effect on a number of factors, including the mRNA expression levels of hepatic iNOS, NF-κB, IL-1β, ICAM-1 and VCAM-1. Notably, the effects of apoM and 10 mg/kg LPS on the levels of IL-6 and IL-10 were the opposite of those induced by 5 mg/kg LPS, which could be associated with the dual anti- and pro-inflammatory effects of IL-6 and IL-10. Collectively, the results of the present study revealed that apoM is an important regulator of inflammatory cytokine and adhesion molecule production in LPS-induced inflammation, which may consequently be associated with the severity of inflammation. These findings indicated that the anti-inflammatory effects of apoM may partly result from the inhibition of the NF-κB pathway.