Macrophage Polarization Research Articles

3D cryo-printed hierarchical porous scaffolds provide immobilization of surface-functionalized sleep-inspired small extracellular vesicles: synergistic therapeutic strategies for vascularized bone regeneration based on macrophage phenotype modulation and angiogenesis-osteogenesis coupling

Bone defect healing is a multi-factorial process involving the inflammatory microenvironment, bone regeneration and the formation of blood vessels, and remains a great challenge in clinical practice. Combined use of three-dimensional (3D)-printed scaffolds and bioactive factors is an emerging strategy for the treatment of bone defects. Scaffolds can be printed using 3D cryogenic printing technology to create a microarchitecture similar to trabecular bone. Melatonin (MT) has attracted attention in recent years as an excellent factor for promoting cell viability and tissue repair. In this study, porous scaffolds were prepared by cryogenic printing with poly(lactic-co-glycolic acid) and ultralong hydroxyapatite nanowires. The hierarchical pore size distribution of the scaffolds was evaluated by scanning electron microscopy (SEM) and micro-computed tomography (micro-CT). Sleep-inspired small extracellular vesicles (MT-sEVs) were then obtained from MT-stimulated cells and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol)-inorganic pyrophosphate (DSPE-PEG-PPi) was used to modify the membrane of MT-sEVs to obtain PPi-MT-sEVs. RNA sequencing was performed to explore the potential mechanisms. The results demonstrated that PPi-MT-sEVs not only enhanced cell proliferation, migration and angiogenesis, but also regulated the osteogenic/adipogenic fate determination and M1/M2 macrophage polarization switch in vitro. PPi-MT-sEVs were used to coat scaffolds, enabled by the capacity of PPi to bind to hydroxyapatite, and computational simulations were used to analyze the interfacial bonding of PPi and hydroxyapatite. The macrophage phenotype-modulating and osteogenesis–angiogenesis coupling effects were evaluated in vivo. In summary, this study suggests that the combination of hierarchical porous scaffolds and PPi-MT-sEVs could be a promising candidate for the clinical treatment of bone defects.Graphical abstract

Tumor- and host-derived heparanase-2 (Hpa2) attenuates tumorigenicity: role of Hpa2 in macrophage polarization and BRD7 nuclear localization

Little attention was given to heparanase 2 (Hpa2) over the last two decades, possibly because it lacks a heparan sulfate (HS)-degrading activity typical of heparanase. Emerging results suggest, nonetheless, that Hpa2 plays a role in human pathologies, including cancer progression where it functions as a tumor suppressor. Here, we examined the role of Hpa2 in cervical carcinoma. We report that high levels of Hpa2 correlate with prolonged survival of cervical carcinoma patients. Strong staining intensity of Hpa2 also correlates with low tumor grade. Overexpression of Hpa2 in SiHa cervical carcinoma cells resulted in tumor xenografts that were two-fold smaller than control tumors. Interestingly, even smaller tumor xenografts were developed by SiHa cells overexpressing the Pro140Arg and Asn543Ile Hpa2 missense mutations that were identified in patients diagnosed with urofacial syndrome (UFS). Utilizing the Ras recruitment system, we identified bromodomain-containing protein 7 (BRD7) to interact with Hpa2 and found that both BRD7 and the Hpa2 mutants are translocated to the cell nucleus in tumors developed by the Pro140Arg and Asn543Ile Hpa2 mutants. Utilizing our newly developed conditional Hpa2-KO mice, we further show that Hpa2 plays a critical role in macrophage polarization; in the absence of Hpa2, macrophages are shifted towards pro-tumorigenic, M2 phenotype. Notably, implanting SiHa cervical carcinoma cells together with Hpa2-KO macrophages promoted tumor growth. These results support, and further expand, the notion that Hpa2 functions as a tumor suppressor, co-operating with another tumor suppressor, BRD7.

Inhibition of fibulin-3 ameliorates periodontal inflammation through reducing M1 macrophage polarization via EGFR/PI3K/AKT pathway.

This study aimed to evaluate the role of fibulin-3 (FBLN3) in macrophage polarization, its mechanism, and its effect on periodontitis. We conducted studies on periodontitis using both clinical samples and ligature-induced mouse periodontitis model. The inflammatory state was assessed using microcomputed tomography, hematoxylin and eosin staining, immunohistochemical staining, and immunofluorescence staining. In vitro, bone marrow-derived macrophages, and RAW 264.7 macrophages were treated with lipopolysaccharide (LPS) and interleukin (IL)-4 to induce polarization. The role of FBLN3 in macrophage polarization was investigated using overexpression plasmids or siRNAs. Furthermore, local injection of adeno-associated virus was employed to suppress FBLN3 expression in periodontal tissues. FBLN3 levels were greater in periodontitis tissues. FBLN3 promoted M1 polarization and suppressed M2 polarization in macrophages. The overexpression of FBLN3 promoted M1 polarization via the EGFR/PI3K/AKT signaling pathway, an effect that the epidermal growth factor receptor (EGFR) inhibitor PD153035 reversed. Suppressing FBLN3 expression improved periodontal inflammation and reduced alveolar bone loss in periodontitis. FBLN3 suppression can mitigate periodontitis by decreasing the M1 macrophage ratio. FBLN3 regulates M1 macrophage polarization through the EGFR/PI3K/AKT signaling pathway. Disruption in the collaboration between extracellular matrix (ECM) and immune system is a significant pathology in periodontitis. Macrophages are a crucial part of the immune system and have unique functions, such as polarization. Fibulin-3, an ECM protein, may play a vital role in this dynamic interplay. Fibulin-3 expression is elevated in periodontitis and is closely related to immune cell function. Inhibiting fibulin-3 can alleviate periodontitis by reducing infiltration of immune cells and M1 macrophage ratio. Furthermore, fibulin-3 promoted macrophage M1 polarization by activating the PI3K/AKT signaling pathway through EGFR binding. Our findings offer a clinically relevant rationale for immune response modulation through fibulin-3.

IDO1-mediated M2 macrophage polarization alleviates the progression of ankylosing spondylitis

Indoleamine 2,3-dioxygenase 1 (IDO1) plays an anti-inflammatory role in autoimmune disease. However, its specific function in ankylosing spondylitis (AS) remain unclear. This study aimed to investigate the potential role of IDO1 in AS. Immunofluorescence, RT-qPCR, and western blot assays were employed to measure gene expression, while ELISA was used to quantify the release of M1 macrophage and M2 macrophage markers. CCK-8, EdU, flow cytometry, ALP staining, and Alizarin red staining (ARS) assays were conducted for functional analysis. JASPAR predicted the binding sites between PPARγ and the promoter, which were further validated by luciferase and ChIP assays. Our findings revealed that the expression of IDO1 was markedly elevated in AS patients. IDO1 overexpression promoted the proliferation of THP-1 cells and M2 macrophage polarization. Conversely, IDO1 knockdown facilitated the osteogenic differentiation of BMSCs. Furthermore, IDO1-mediated upregulation of PPARγ modulated RUNX2 transcription. PPARγ overexpression counteracted the effects of IDO1 knockdown, thereby inhibiting the osteogenic differentiation of BMSCs. In conclusion, the IDO1/PPARγ/RUNX2 signaling pathway may protect against AS by promoting M2 macrophage polarization and inhibiting osteogenic differentiation.

Bexarotene ameliorated the pulmonary inflammation and M1 polarization of alveolar macrophages induced by cigarette smoke via PPARγ/HO-1

BackgroundAlveolar macrophages (AMs) modulate pulmonary inflammation in chronic obstructive pulmonary disease (COPD), contributing to its progression. The PPARγ/RXRα heterodimer influences AM polarization induced by cigarette smoke (CS). Although PPARγ agonists suppress CS-induced M1 macrophage polarization, the impact of RXRα agonists on this process has not been determined. This study explored the effects and mechanisms of the RXRα agonist bexarotene on macrophage polarization in a COPD mouse model.MethodsC57BL/6 mice were assigned to the control, model, bexarotene, or model + bexarotene group. The COPD model was induced by CS exposure and intraperitoneal injection of cigarette smoke extract (CSE), followed by intraperitoneal administration of bexarotene. Additionally, MH-S cells were exposed to CSE and bexarotene. Lung tissues were subjected to hematoxylin-eosin staining, and emphysema and inflammatory scores were assessed. Cytokine levels and cell differentials in bronchoalveolar lavage fluid were measured, and macrophage polarization was evaluated using immunohistochemistry, flow cytometry, and qPCR.ResultsBexarotene effectively reduced inflammatory scores, cytokine levels, and neutrophil counts and ameliorated emphysema and M1 polarization of AMs in COPD model mice. Furthermore, while CSE exposure reduced PPARγ expression and the transcriptional activity of AMs, bexarotene enhanced the transcriptional response of PPARγ to CSE. HO-1 was identified as a potential target of PPARγ; its levels were assessed in AMs, revealing that bexarotene mitigated the CSE-induced reduction in HO-1. Notably, the effect of bexarotene was partially inhibited by the PPARγ inhibitor.ConclusionsOur results indicated that bexarotene may curb inflammation and M1 polarization in COPD through activation of the PPARγ/HO-1 pathway.

Umbilical cord-derived mesenchymal stem cells preferentially modulate macrophages to alleviate pulmonary fibrosis

BackgroundIdiopathic Pulmonary Fibrosis (IPF) is a type of interstitial lung disease characterized by chronic inflammation due to persistent lung damage. Mesenchymal stem cells (MSCs), including those derived from the umbilical cord (UCMSCs) and placenta (PLMSCs), have been utilized in clinical trials for IPF treatment. However, the varying therapeutic effectiveness between these two MSC types remains unclear.MethodsIn this study, we examined the therapeutic differences between UCMSCs and PLMSCs in treating lung damage using a bleomycin (BLM)-induced pulmonary injury mouse model.ResultsWe showed that UCMSCs had a superior therapeutic impact on lung damage compared to PLMSCs. Upon cytokine stimulation, UCMSCs expressed higher levels of inflammation-related genes and more effectively directed macrophage polarization towards the M2 phenotype than PLMSCs, both in vitro and in vivo. Furthermore, UCMSCs showed a preference for expressing CC motif ligation 2 (CCL2) and C-X-C motif chemokine ligand 1 (CXCL1) compared to PLMSCs. The expression of secreted phosphoprotein 1 (SPP1), triggering receptor expressed on myeloid cells 2 (Trem2), and CCAAT enhancer binding protein beta (Cebpb) in macrophages from mice with the disease treated with UCMSCs was significantly reduced compared to those treated with PLMSCs. Conclusions: Therefore, UCMSCs demonstrated superior anti-fibrotic abilities in treating lung damage, potentially through inducing a more robust M2 polarization of macrophages than PLMSCs.

Pathologic function and therapeutic potential of extracellular vesicle miRNA in sepsis

Sepsis is a systemic inflammatory response initiated by an infection, which can lead to multi-organ dysfunction. The pathophysiology of sepsis is complex, and treatment options are limited. Traditional antibiotic therapies have shown limitations, such as promoting the emergence of antibiotic-resistant bacteria and disrupting the natural microbiota. Consequently, there is a pressing need to explore diverse therapeutic approaches for sepsis management. Extracellular vesicles, which play a crucial role in cell-to-cell communication, are released by various cell types throughout the body and possess a membrane structure composed of a lipid bilayer. MicroRNAs may be encapsulated within these structures and can be selectively delivered to target recipient cells through the activation of cell surface receptors or via endocytosis and fusion, thereby modulating the biological functions of target cells. The article examines the pathological alterations that happen as sepsis progresses and the biological control of extracellular vesicles and microRNAs in sepsis. This review focuses on the role of extracellular vesicles and their microRNAs on controlling the inflammatory response, macrophage polarization, programmed cell death, endothelial dysfunction, and microcirculatory changes in sepsis. Furthermore, the obstacles encountered by this novel therapy are also examined.

Remodel Heterogeneous Electrical Microenvironment at Nano-Scale Interface Optimizes Osteogenesis by Coupling of Immunomodulation and Angiogenesis.

Immunomodulation is essential for implants to regulate tissue regeneration, while bioelectricity plays a fundamental role in regulating immune activities. Under natural preferences, the bone matrix electrical microenvironment is heterogeneous in the nanoscale, which provides fundamental electrical cues to regulate bone immunity and regenerative repair. However, remodeling bone nanoscale heterogeneous electrical microenvironment remains a challenge, and the underlying immune modulation mechanism remains to be explored. In this research, in situ discretely distributed nano-heterojunctions are constructed on titanium oxide nanofibers to mimic the heterogeneous electrical microenvironment exhibited by bone collagen fibers. The material is identified to directly regulate calcium ion channeling for anti-inflammatory polarization of macrophages. Surprisingly, the highly biomimetic heterogeneous electrical microenvironment can induce a pro-angiogenic phenotypic transformation of macrophages, leading to enhanced neo-vascularization at the early stage of osteogenesis. Mechanistic exploration identifies that PI3K signaling pathway-mediated FGF2 secretion may partially explain for strengthened coupling of immunomodulation and angiogenesis, which optimizes subsequent bone regeneration. These findings highlight the significance of biomimetic heterogeneous electrical cues on immune-modulation and provide a design principle for future electroactive implant materials.

Quinoidal Semiconductor Nanoparticles for NIR-II Photoacoustic Imaging and Photoimmunotherapy of Cancer.

Photoagents with ultra-high near-infrared II (NIR-II) light energy conversion efficiency hold great promise in tumor phototherapy due to their ability to penetrate deeper tissues and minimize damage to surrounding healthy cells. However, the development of NIR-II photoagents remain challenging. In this study, an all-fused-ring quinoidal acceptor-donor-acceptor (A-D-A) molecule, SKCN, with a BTP core is synthesized, and nanoparticles named FA-SNPs are prepared. The unique quinoidal structure enhances π-electron delocalization and bond length uniformity, significantly reducing the bandgap of SKCN, resulting in strong NIR-II absorption, a high molar extinction coefficient, and a photothermal conversion efficiency of 75.14%. Enhanced molecular rigidity also facilitates efficient energy transfer to oxygen, boosting reactive oxygen species generation. By incorporating the immunomodulator R848, FA-SRNPs nanoparticles are further developed, effectively modulating the tumor immune microenvironment by reducing Tregs and M-MDSCs infiltration, promoting dendritic cell maturation, M1 macrophage polarization, and activating CD8+ T cells and NK cells. Comprehensive studies using orthotopic ovarian cancer models demonstrated strong tumor targeting, photoacoustic imaging capabilities, and significant tumor suppression and metastasis inhibition, and also showing excellent therapeutic efficacy in an orthotopic breast cancer model. This study provides strong evidence for the potential application of quinoidal A-D-A molecules in cancer photoimmunotherapy.

Quercetin-Loaded Melanin Nanoparticles Decorated with Collagenase Mediates Synergistic Immunomodulation and Restores Extracellular Matrix Homeostasis in Liver Fibrosis.

Liver fibrosis is a chronic disease that lacks effective drug treatment. Chronic damage and inflammation lead to the formation of collagen and fibrous scars. However, the excessive accumulation of collagen I significantly hinders the delivery of drugs into liver tissue. Therefore, this study developed a quercetin-loaded melanin nanoparticle codecorated collagenase (MNP-QUE-COL) for the treatment of liver fibrosis. These results showed that MNP-QUE-COL degraded excessive collagen I, thereby efficiently delivering melanin and quercetin into the liver tissue. MNP-QUE-COL exhibited optimal PA/MRI dual-mode imaging ability. In addition, the synergistic anti-inflammatory and reactive oxygen species scavenging function of quercetin and melanin was achieved by regulation of M1-M2 macrophage polarization and inhibition of pro-inflammatory cytokine release, reshaping the imbalanced extracellular interstitial inflammatory environment. The results of this research suggest that MNP-QUE-COL is a safe and efficient therapeutic nanoplatform for liver fibrosis, showing promise as a potential therapeutic strategy for liver fibrosis and associated diseases.

Lung dECM matrikine-based hydrogel reverses bleomycin-induced pulmonary fibrosis by suppressing M2 macrophage polarization.

Recent studies have shown promising results using decellularized extracellular matrix (dECM) matrikines-based hydrogel as attractive strategies for preventing and alleviating fibrosis.
Methods & Results: Porcine lung decellularization and pepsin digestion were used to prepare the lung dECM hydrogel. Proteomic analysis revealed that the lung dECM hydrogel was enriched in glycoproteins, collagens, laminins, fibrinogen, held receptors, and bound growth factors. With porous structures and good mechanical properties and stability, the lung dECM hydrogel showed low cytotoxicity and good biocompatibility both in vitro and in vivo. The lung dECM hydrogel was further administered to verify the safety and effectiveness of reversing pulmonary fibrosis in a bleomycin induced rat model. The results revealed a relatively complete alveolar structure with less inflammatory infiltration and a reduced amount of collagen fiber deposition. TMT quantification proteomic analyses revealed significant downregulation of proteins, pathways, and interactions involved in the regulation of ECM components, tissue remodeling, inflammation, and the cytoskeleton and indicated that fibrosis-related proteins were obviously downregulated and inflammation-related proteins were significantly changed, particularly in macrophages, after administration of the lung dECM hydrogel. Multiplex immunohistochemical (mIHC) staining of lung tissue revealed that the inflammatory response was regulated by the lung dECM hydrogel, as indicated by a decrease in the number of CD3+ T cells and macrophages and the suppression of M2 macrophage polarization. Gene set enrichment analysis revealed that downregulated ficolin signaling was enriched in macrophages after lung dECM hydrogel administration, and the findings were verified in lung tissue by mIHC. Additionally, the effects of ficolin B proteins on macrophage polarization were proved in vitro.
Conclusion: This study suggested that the lung dECM hydrogel can reverse pulmonary fibrosis by suppressing M2 macrophage polarization through downregulation of the ficolin signaling pathway. Thus, the dECM hydrogel represent a promising class of biological materials for use in regenerative medicine.

Activated hepatic stellate cell-derived small extracellular vesicles facilitate M2 macrophage polarization and hepatoma progression via miR-27a-3p

The progression of hepatoma is heavily influenced by the microenvironment. Tumor-associated macrophages (TAMs) are considered to play a critical role in the tumor microenvironment (TME) and increase the aggressiveness of hepatoma. The activation of hepatic stellate cells (HSCs) is involved in hepatoma progression, and accumulating evidence demonstrates a change in microRNA (miRNA) expression during HSC activation. Therefore, the potential roles of HSCs-related miRNAs in macrophage differentiation and hepatoma progression deserve to be explored. The present study aimed to investigate the effects of miRNAs carried by small extracellular vesicles (sEVs) released by activated HSCs on hepatoma progression. The results indicated that miR-27a-3p was significantly upregulated in cells and corresponding sEVs during the activation of primary rat HSCs and human HSC line-LX2 cells. Furthermore, miR-27a-3p contributed to the proliferation and migration of hepatoma cells and promoted M2 polarization of macrophage. HSC-sEVs overexpressing miR-27a-3p can directly facilitate tumor progression and modulate macrophage polarization, indirectly contributing to hepatoma progression. Finally, Sprouty2 (SPRY2) was verified to be the target gene of miR-27a-3p. In conclusion, activated HSC-derived sEVs with high levels of miR-27a-3p might induce M2 macrophage polarization and promote hepatoma progression, providing new insights into the mechanism of hepatoma progression.

Gene-Activating Framework Nucleic Acid-Targeted Upregulating Sirtuin-1 to Modulate Osteoimmune Microenvironment for Diabetic Osteoporosis Therapeutics.

Diabetic osteoporosis, a prevalent chronic complication of diabetes, is marked by reduced bone mass, increased bone fragility, and susceptibility to fractures. A significant cause of this condition is the disruption of osteoblastic homeostasis due to prolonged hyperglycemia, which impedes bone regeneration and remodeling. Despite its prevalence, no effective treatments specifically target diabetic osteoporosis. Recently, small-activating RNA (saRNA) therapy has attracted attention for its targeting capacity, high efficacy, and minimal side effects. However, RNA's inherent properties, such as structural instability, susceptibility to degradation, and poor penetration, limit its applications. To address these limitations, a gene-activating tetrahedral framework nucleic acid (tFNA) with sirtuin-1 (SIRT1) gene activation function is developed, termed Tsa. Tsa exhibits an RNA-protecting effect and can effectively penetrate cell membranes to upregulate SIRT1 gene expression. At the histological level, Tsa treatment alleviates diabetic osteoporosis by increasing bone trabecular density and promoting new bone formation. At the cellular level, it switches macrophage polarization toward the anti-inflammatory M2 phenotype while inhibiting the inflammatory M1 phenotype, creating a favorable bone immune microenvironment for osteoblasts. At the genetic level, Tsa activates SIRT1 expression, which deacetylates Acetyl-p65 to block the NF-κB pathway and restore the osteoimmune environment. Overall, this research demonstrates a nanodrug "Tsa", capable of activating SIRT1 and modulating the bone immune environment, thereby showcasing its immense potential for diabetic osteoporosis treatment.

Vitamin D 1,25-Dihydroxyvitamin D3 reduces lipid accumulation in hepatocytes by inhibiting M1 macrophage polarization

BACKGROUND Non-alcoholic fatty liver disease (NAFLD), which is a significant liver condition associated with metabolic syndrome, is the leading cause of liver diseases globally and its prevalence is on the rise in most nations. The protective impact of vitamin D on NAFLD and its specific mechanism remains unclear. AIM To examine the role of vitamin D in NAFLD and how vitamin D affects the polarization of hepatic macrophages in NAFLD through the vitamin D receptor (VDR)-peroxisome proliferator activated receptor (PPAR)γ pathway. METHODS Wild-type C57BL/6 mice were provided with a high-fat diet to trigger NAFLD model and administered 1,25-dihydroxy-vitamin D [1,25(OH)2D3] supplementation. 1,25(OH)2D3 was given to RAW264.7 macrophages that had been treated with lipid, and a co-culture with AML12 hepatocytes was set up. Lipid accumulation, lipid metabolism enzymes, M1/M2 phenotype markers, proinflammatory cytokines and VDR-PPARγ pathway were determined. RESULTS Supplementation with 1,25(OH)2D3 relieved hepatic steatosis and decreased the proinflammatory M1 polarization of hepatic macrophages in NAFLD. Administration of 1,25(OH)2D3 suppressed the proinflammatory M1 polarization of macrophages induced by fatty acids, thereby directly relieving lipid accumulation and metabolism in hepatocytes. The VDR-PPARγ pathway had a notable impact on reversing lipid-induced proinflammatory M1 polarization of macrophages regulated by the administration of 1,25(OH)2D3. CONCLUSION Supplementation with 1,25(OH)2D3 improved hepatic steatosis and lipid metabolism in NAFLD, linked to its capacity to reverse the proinflammatory M1 polarization of hepatic macrophages, partially by regulating the VDR-PPARγ pathway. The involvement of 1,25(OH)2D3 in inhibiting fatty-acid-induced proinflammatory M1 polarization of macrophages played a direct role in relieving lipid accumulation and metabolism in hepatocytes.

CD11b deficiency attenuates the ischemia/reperfusion-induced AKI-to-CKD process by regulatingmacrophage polarization.

Severe acute kidney injury (AKI) is a risk factor for the future development of chronic kidney disease (CKD), and macrophages are an essential cell group implicated in injury, repair, and fibrosis during this progress. However, the underlying mechanism of how macrophages participate in the development of the disease is largely unclear. CD11b (Integrin αM) is highly expressed in monocytes/macrophages and has been verified to mediate broad functions. We found that CD11b-knockout mice were protected from the ischemia/reperfusion-induced AKI-to-CKD process. Additionally, renal macrophages from the kidneys of CD11b-deficient mice presented an M2-like, anti-inflammatory phenotype. We demonstrated both invitro and invivo that enhanced alternative activation in CD11b-knockout macrophages is regulated by the interleukin (IL)-4/signal transducer and activator of transcription (STAT) 6 axis, which is mediated by the inactivation of the Src-family kinase (SFK) member Lyn. Importantly, the therapeutical administration of CD11b-neutralizing antibody can effectively prevent AKI-to-CKD progress. Thus, our study verifies that CD11b plays a critical role in limiting the alternative activation of macrophages and may be a potential therapeutic target during the AKI-to-CKD process.

From Tea to Functional Foods: Exploring Caryopteris mongolica Bunge for Anti-Rheumatoid Arthritis and Unraveling Its Potential Mechanisms

Background: Caryopteris mongolica Bunge (CM) shows promising potential for managing rheumatoid arthritis (RA) and digestive disorders, attributed to its rich content of bioactive compounds such as polyphenols and flavonoids. Despite its common use in herbal tea, the specific mechanisms underlying CM’s anti-inflammatory and joint-protective effects remain unclear, limiting its development as a functional food. This study investigated the effects of aqueous CM extract on RA in collagen-induced arthritis (CIA) rats and explored the underlying mechanisms. Methods: Forty-eight female Sprague-Dawley rats were randomly assigned to six groups (n = 8): normal control, CIA model, methotrexate (MTX), and CM high-, middle-, and low-dose groups. Anti-inflammatory and joint-protective effects were evaluated using biochemical and histological analyses. To elucidate the mechanisms, we applied metabolomics, network pharmacology, and transcriptomics approaches. Results: The results demonstrated that CM extract effectively suppressed synovial inflammation in CIA rats, reducing joint degradation. CM’s anti-inflammatory effects were mediated through the TNF signaling pathway, modulating glycerophospholipid and amino acid metabolism, including reduced levels of tryptophan, LysoPC, and asparagine. Molecular docking identified scutellarin and apigenin as key bioactive compounds. Additionally, immunofluorescence analysis revealed CM’s therapeutic effects via TNF signaling inhibition and suppression of M1 macrophage polarization. Conclusions: These findings highlight the therapeutic potential of CM for RA and support its development as a functional food or pharmaceutical product.

Spermine synthase engages in macrophages M2 polarization to sabotage antitumor immunity in hepatocellular carcinoma.

Disturbances in tumor cell metabolism reshape the tumor microenvironment (TME) and impair antitumor immunity, but the implicit mechanisms remain elusive. Here, we found that spermine synthase (SMS) was significantly upregulated in tumor cells, which correlated positively with the immunosuppressive microenvironment and predicted poor survival in hepatocellular carcinoma (HCC) patients. Via "subcutaneous" and "orthotopic" HCC syngeneic mouse models and a series of in vitro coculture experiments, we identified elevated SMS levels in HCC cells played a role in immune escape mainly through its metabolic product spermine, which induced M2 polarization of tumor-associated macrophages (TAMs) and subsequently corresponded with a decreased antitumor functionality of CD8+ T cells. Mechanistically, we discovered that spermine reprogrammed TAMs mainly by activating the PI3K-Akt-mTOR-S6K signaling pathway. Spermine inhibition in combination with immune checkpoint blockade effectively diminished tumor burden in vivo. Our results expand the understanding of the critical role of metabolites in regulating cancer progression and antitumor immunity and open new avenues for developing novel therapeutic strategies against HCC.

RasGRP4 aggravates ischemia-reperfusion injury in diabetic kidneys by mediating communication between macrophages and T cells.

Diabetes mellitus (DM) is acknowledged as an independent risk factor for acute kidney injury. Ras guanine nucleotide-releasing protein-4 (RasGRP4) exerts a notable role in modulating immune-inflammatory responses and kidney disease progression in diabetes. Herein, we delved into the specific role and mechanism of RasGRP4 in diabetic renal ischemia-reperfusion injury. Diabetes was induced by a high-fat diet and STZ injections, followed by creating an ischemia-reperfusion kidney injury via renal pedicle clamping and reperfusion. In vitro, a high glucose and hypoxia-reoxygenation modeled cellular inflammatory injury. We found RasGRP4 knockout (KO) mice, compared to C57BL/6J (WT) mice, showed markedly less renal dysfunction and fibrosis in diabetic ischemia-reperfusion injury. There was a significant decrease in the renal infiltration of M1 macrophages and Th17 cells, along with downregulated IL17 pathway proteins and effectors. In vitro, RasGRP4 deletion restrained M1 macrophage polarization and Th17 cell differentiation, inhibiting the IL17 signaling pathway in HK-2 cells. Hyperglycemia intensified renal inflammation state. Together, RasGRP4, through the regulation of interactions among M1 macrophages, CD4+ T cells and HK-2 cells, formed a cascade that intensified the inflammatory storm activity, ultimately exacerbating the inflammatory injury of diabetic ischemia-reperfusion kidneys. DM intensified this inflammatory injury mechanism, worsening the injury from renal ischemia-reperfusion.

Development of anti-cancer drugs for tumor-associated macrophages: a comprehensive review and mechanistic insights

This review provides an in-depth summary of the development of anti-cancer drugs for tumor-associated macrophages (TAMs), with a particular focus on the development and tissue specialization of macrophages, and factors influencing the polarization of M1 and M2 macrophages, and mechanistic insights underlying the targeting therapeutic approaches. TAMs, pivotal in the tumor microenvironment, exhibit notable plasticity and diverse functional roles. Influenced by the complex milieu, TAMs polarize into M1-type, which suppresses tumors, and M2-type, which promotes metastasis. Notably, targeting M2-TAMs is a promising strategy for tumor therapy. By emphasizing the importance of macrophages as a therapeutic target of anti-cancer drugs, this review aims to provide valuable insights and research directions for clinicians and researchers.

Synergistic combinations of Angelica sinensis for myocardial infarction treatment: network pharmacology and quadratic optimization approach

Background and aimAngelica sinensis (Oliv.) Diels (Danggui, DG), exhibits potential in myocardial infarction (MI) treatment. However, research on its synergistic combinations for cardioprotective effects has been limited owing to inadequate approaches.Experimental procedureWe identified certain phenolic acids and phthalein compounds in DG. Network pharmacology analysis and experimental validation revealed the components that protected H9c2 cells and reduced lactate dehydrogenase levels. Subsequently, a combination of computational experimental strategies and a secondary phenotypic optimization platform was employed to identify effective component combinations with synergistic interactions. The Chou-Talalay and Zero Interaction Potency (ZIP) models were utilized to quantify the synergistic relationships. The optimal combination identified, Z-Ligustide and Chlorogenic acid (Z-LIG/CGA), was evaluated for its protective effects on cardiac function and cardiomyocytes apoptosis induced by inflammatory in a mouse model of induced by left anterior descending coronary artery ligation. Flow cytometry was further utilized to detect the polarization ratio of M1/M2 macrophages and the expression of inflammatory cytokines in serum was measured, assessing the inhibition of inflammatory responses and pro-inflammatory signaling factors by Z-LIG/CGA.Key resultsQuadratic surface analysis revealed that the Z-LIG/CGA combination displayed synergistic cardioprotective effects (combination index value <1; ZIP value >10). In vivo, Z-LIG/CGA significantly improved cardiac function and reduced the fibrotic area in mice post-MI, surpassing the results in groups treated with Z-LIG or CGA alone. Compared to the MI group, the Z-LIG/CGA group exhibited decreased ratios of the myocardial cell apoptosis-related proteins BAX/Bcl-2 and Cleaved Caspase-3/Caspase-3 in mice. Further research revealed that Z-LIG/CGA treatment significantly increased IL-1R2 levels, significantly decreased IL-17RA levels, and inhibited the activation of p-STAT1, thereby alleviating cell apoptosis after MI. Additionally, the Z-LIG/CGA combination significantly inhibited the ratio of M1/M2 macrophages and suppressed the expression levels of pro-inflammatory cytokines IL-1β, IL-6, IL-17, and TNF-α in the serum.Conclusion and implicationsWe successfully identified a synergistic drug combination, Z-LIG/CGA, which improves MI outcomes by inhibiting cardiomyocyte apoptosis and inflammatory damage through modulating macrophage polarization and regulating the IL-1R2/IL-17RA/STAT1 signaling pathway. This study provides a charming paradigm to explore effective drug combinations in traditional Chinese medicine and a promising treatment for MI.