Chronic Inflammatory Microenvironment Research Articles

Immunomodulatory Hydrogel for Electrostatically Capturing Pro-inflammatory Factors and Chemically Scavenging Reactive Oxygen Species in Chronic Diabetic Wound Remodeling.

Diabetic wound exhibits the complex characteristics involving continuous oxidative stress and excessive expression of pro-inflammatory cytokines to cause a long-term inflammatory microenvironment. The repair healing of chronic diabetic wounding is tremendously hindered due to persistent inflammatory reaction. To address the aforementioned issues, here, a dual-functional hydrogel is designed, consisting of N1-(4-boronobenzyl)-N3-(4-boronophenyl)-N1, N1, N3, N3-tetramethylpropane-1, 3-diaminium (TSPBA) modified polyvinyl alcohol (PVA) and methacrylamide carboxymethyl chitosan (CMCSMA) can not only electrostatically adsorb proinflammatory cytokines of IL1-β and TNF-α, but can also chemically scavenge the excessive reactive oxygen species (ROS) in situ. Both in vitro and in vivo evaluations verify that the negatively charged and ROS-responsive hydrogel (NCRH) can effectively modulate the chronic inflammatory microenvironment of diabetic wounds and significantly enhance wound remodeling. More importantly, the well-designed NCRH shows a superior skin recovery in comparison with the commercial competitor product of wound dressing. Consequently, the current work highlights the need for new strategies to expedite the healing process of diabetic wounds and offers a wound dressingmaterial with immunomodulation.

P-303 Calcitonin Gene-Related Protein as a key driver of myometrial fibrogenesis in adenomyosis pathology

Abstract Study question Does CGRP play a role in the fibrosis of adenomyosis lesions? Summary answer CGRP converts fibroblasts to myofibroblasts in adenomyosis lesions via the RAMP1 receptor and participates in the inflammatory activation processes. What is known already Adenomyosis is a prevalent and challenging disease in gynecology. It is characterized by the invasion of endometrial glands and mesenchyme into the myometrium, resulting in the development of limited or diffuse lesions. These lesions interact with in situ fibroblasts and recruit immune cells, leading to a chronic and persistent inflammatory microenvironment, which ultimately contributes to myometrial fibrosis. One of the typical clinical symptoms of adenomyosis is secondary progressive dysmenorrhea. Accumulated research suggests that sensory nerves, which are implicated in dysmenorrhea, and neuropeptides such as CGRP play a role in the development of ectopic lesions, thus establishing a feed-forward cycle. Study design, size, duration This study employed a laboratory-based experimental design. The in vitro experiment included a total of 67 clinical samples and the in vivo part included 57 ICR mice as subjects, conducted over 20 weeks, with data collection taking place between August 2023 and December 2023. Participants/materials, setting, methods Myometrium samples were collected from 37 women with adenomyosis, while control samples were obtained from 30 women without adenomyosis. Among them, the tissues from three adenomyosis patients and three control patients were subjected to scRNA-seq, and the other 61 samples were for validation. A mouse model of adenomyosis was established by administering tamoxifen. The mice were divided into three groups: a control group, a model group, and a treatment group that received Rimegepant via gavage. Main results and the role of chance In adenomyosis tissue, an enrichment of sensory nerve fibers, elevated expression of nerve-related proteins（NGF, PGP9.5）, and increased CGRP expression and its receptor RAMP1 were observed. Furthermore, the qRT-PCR results demonstrated that the adenomyosis lesions were in a chronic inflammatory state which is consistent with the scRNA-seq result. Moreover, the scRNA-seq data suggested a high expression of the CGRP receptor (RAMP1) on fibroblasts, which plays a critical role in causing fibrosis in adenomyosis. Additionally, it was found that CGRP prompted the transition of fibroblasts to myofibroblasts (FMT), and the activated fibroblasts, in turn, attracted macrophages and stimulated their shift towards an M1 phenotype. These significant findings were further confirmed through experimental animal studies. The fertility outcome indicated a positive trend, with the Rimegepant group showing an increased embryo implantation rate. Limitations, reasons for caution In the present experiment, while we have confirmed the involvement of CGRP in the fibrogenesis of adenomyosis, further investigation is needed to understand the specific biological processes occurring in fibroblasts following CGRP administration. Wider implications of the findings Limited research has been conducted on the association between adenomyosis and sensory nerves. This study adds the existing evidence by demonstrating the crucial role of sensory nerves and CGRP in promoting fibrosis. The findings of this study offer new perspectives on the treatment and understanding of the pathogenesis of adenomyosis. Trial registration number not applicable

Early onset of pathological polyploidization and cellular senescence in hepatocytes lacking RAD51 creates a pro-fibrotic and pro-tumorigenic inflammatory microenvironment.

RAD51 is a highly conserved DNA repair protein and is indispensable for embryonic viability. As a result, the role of RAD51 in liver development and function is unknown. Our aim was to characterize the function of RAD51 in postnatal liver development. RAD51 is highly expressed during liver development and during regeneration following hepatectomy and hepatic injury, and is also elevated in chronic liver diseases. We generated hepatocyte-specific Rad51 deletion mouse model using Alb-Cre (Rad51-CKO) and AAV8-TBG-Cre to evaluate the function of RAD51 in liver development and regeneration. The phenotype in Rad51-CKO mice is dependent on Cre recombinase dosage, with Rad51fl/fl; Alb-Cre+/+ manifesting a more severe phenotype than the Rad51fl/fl; Alb-Cre+/- mice. RAD51 deletion in postnatal hepatocytes results in aborted mitosis and early onset of pathological polyploidization that is associated with oxidative stress and cellular senescence. Remarkable liver fibrosis occurs spontaneously as early as in 3-month-old Rad51fl/fl; Alb-Cre+/+ mice. While liver regeneration is compromised in Rad51-CKO mice, they are more tolerant of carbon tetrachloride (CCl4)-induced hepatic injury and resistant to DEN/CCl4-induced hepatocellular carcinoma (HCC). A chronic inflammatory microenvironment created by the senescent hepatocytes appears to activate ductular reaction and consequently a transdifferentiation of cholangiocytes to hepatocytes. The newly-derived RAD51 functional immature hepatocytes proliferate vigorously, acquire increased malignancy, and eventually give rise to HCC. Our results demonstrate a novel function of RAD51 in liver development, homeostasis and tumorigenesis. The Rad51-CKO mice represent a unique genetic model for premature liver senescence, fibrosis and hepatocellular carcinogenesis.

TGF-β1 induces PD-1 expression in macrophages through SMAD3/STAT3 cooperative signaling in chronic inflammation.

Programmed cell death protein 1 (PD-1), a coinhibitory T cell checkpoint, is also expressed on macrophages in pathogen- or tumor-driven chronic inflammation. Increasing evidence underscores the importance of PD-1 on macrophages for dampening immune responses. However, the mechanism governing PD-1 expression in macrophages in chronic inflammation remains largely unknown. TGF-β1 is abundant within chronic inflammatory microenvironments. Here, based on public databases, significantly positive correlations between PDCD1 and TGFB1 gene expression were observed in most human tumors. Of note, among immune infiltrates, macrophages as the predominant infiltrate expressed higher PDCD1 and TGFBR1/TGFBR2 genes. MC38 colon cancer and Schistosoma japonicum infection were used as experimental models for chronic inflammation. PD-1hi macrophages from chronic inflammatory tissues displayed an immunoregulatory pattern and expressed a higher level of TGF-β receptors. Either TGF-β1-neutralizing antibody administration or macrophage-specific Tgfbr1 knockdown largely reduced PD-1 expression on macrophages in animal models. We further demonstrated that TGF-β1 directly induced PD-1 expression on macrophages. Mechanistically, TGF-β1-induced PD-1 expression on macrophages was dependent on SMAD3 and STAT3, which formed a complex at the Pdcd1 promoter. Collectively, our study shows that macrophages adapt to chronic inflammation through TGF-β1-triggered cooperative SMAD3/STAT3 signaling that induces PD-1 expression and modulates macrophage function.

Yanggan Jiangmei Formula alleviates hepatic inflammation and lipid accumulation in non-alcoholic steatohepatitis by inhibiting the NF-κB/NLRP3 signaling pathway

The role of NF-κB and the NLRP3 inflammasome in the chronic inflammatory microenvironment of non-alcoholic steatohepatitis (NASH) has been posited as crucial. The Yanggan Jiangmei Formula (YGJMF) has shown promise in ameliorating hepatic steatosis in NASH patients, yet its pharmacological mechanisms remain largely unexplored. This study was conducted to investigate the efficacy of YGJMF in NASH and to elucidate its pharmacological underpinnings. To simulate NASH both in vivo and in vitro, high-fat-diet (HFD) rats and HepG2 cells stimulated with free fatty acids (FFAs) were utilized. The severity of liver injury and lipid deposition was assessed using serum indicators, histopathological staining, micro-magnetic resonance imaging (MRI), and the liver-to-muscle signal intensity ratio (SIRL/M). Furthermore, a combination of enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), immunofluorescence, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blotting analyses was employed to investigate the NF-κB/NLRP3 signaling pathway and associated cytokine levels. The results from liver pathology, MRI assessments, and biochemical tests in rat models demonstrated YGJMF's significant effectiveness in reducing liver damage and lipid accumulation. Additionally, YGJMF markedly reduced hepatocyte inflammation by downregulating inflammatory cytokines in both liver tissue and serum. Furthermore, YGJMF was found to disrupt NF-κB activation, consequently inhibiting the assembly of the NLRP3 inflammasome in both the in vitro and in vivo models. The preliminary findings of this study suggest that YGJMF may alleviate hepatic steatosis and inhibit the NF-κB/NLRP3 signaling pathway, thereby exerting anti-inflammatory effects in NASH.

Musculoskeletal imaging of senescence.

Senescent cells play a vital role in the pathogenesis of musculoskeletal (MSK) diseases, such as chronic inflammatory joint disorders, rheumatoid arthritis (RA), and osteoarthritis (OA). Cellular senescence in articular joints represents a response of local cells to persistent stress that leads to cell-cycle arrest and enhanced production of inflammatory cytokines, which in turn perpetuates joint damage and leads to significant morbidities in afflicted patients. It has been recently discovered that clearance of senescent cells by novel "senolytic" therapies can attenuate the chronic inflammatory microenvironment of RA and OA, preventing further disease progression and supporting healing processes. To identify patients who might benefit from these new senolytic therapies and monitor therapy response, there is an unmet need to identify and map senescent cells in articular joints and related musculoskeletal tissues. To fill this gap, new imaging biomarkers are being developed to detect and characterize senescent cells in human joints and musculoskeletal tissues. This review article will provide an overview of these efforts. New imaging biomarkers for senescence cells are expected to significantly improve the specificity of state-of-the-art imaging technologies for diagnosing musculoskeletal disorders.

JAK3/STAT5 signaling-triggered upregulation of PIK3CD contributes to gastric carcinoma development.

Gastric cancer (GC) is one of the most common solid cancers with high incidence and mortality worldwide. Chronic gastritis and consequent inflammatory microenvironment is known as a major cause leading to gastric carcinogenesis. Here we report that PIK3CD that encodes p110δ, a catalytic subunit of the class IA PI3Ks, is overexpressed and tumorigenic in GC and associated with tumor inflammatory microenvironment. By investigating the data from TCGA database and our immunohistochemical staining and quantitative real-time PCR results from clinical samples, we found PIK3CD exhibits higher expression level in GC tissues compared with adjacent non-tumorous stomach tissues. Genetic silencing of PIK3CD in GC cells retards proliferation and migration in vitro and tumorigenicity and metastasis in vivo. In contrast, enhanced expression of PIK3CD promotes these phenotypes in vitro. Furthermore, pharmacological inhibition of PIK3CD could reduce GC cell viability and colony formation capacities. More importantly, we reveal a relevant mechanism that PIK3CD, but not PIK3CA and PIK3CB, is transcriptionally regulated by the pro-inflammatory IL2/JAK3/STAT5 axis and tumor-infiltrating immune cells such as lymphocytes. These observations may setup a new crosstalk between tumor inflammatory microenvironment, IL2/JAK3/STAT5 signaling and PI3K/AKT signaling. Targeting PIK3CD may be a promising therapy strategy for GC.

Nucleus pulposus cells regulate macrophages in degenerated intervertebral discs via the integrated stress response-mediated CCL2/7-CCR2 signaling pathway

Lower back pain (LBP), which is a primary cause of disability, is largely attributed to intervertebral disc degeneration (IDD). Macrophages (MΦs) in degenerated intervertebral discs (IVDs) form a chronic inflammatory microenvironment, but how MΦs are recruited to degenerative segments and transform into a proinflammatory phenotype remains unclear. We evaluated chemokine expression in degenerated nucleus pulposus cells (NPCs) to clarify the role of NPCs in the establishment of an inflammatory microenvironment in IDD and explored the mechanisms. We found that the production of C-C motif chemokine ligand 2 (CCL2) and C-C motif chemokine ligand 7 (CCL7) was significantly increased in NPCs under inflammatory conditions, and blocking CCL2/7 and their receptor, C-C chemokine receptor type 2(CCR2), inhibited the inductive effects of NPCs on MΦ infiltration and proinflammatory polarization. Moreover, activation of the integrated stress response (ISR) was obvious in IDD, and ISR inhibition reduced the production of CCL2/7 in NPCs. Further investigation revealed that activating Transcription Factor 3 (ATF3) responded to ISR activation, and ChIP-qPCR verified the DNA-binding activity of ATF3 on CCL2/7 promoters. In addition, we found that Toll-like receptor 4 (TLR4) inhibition modulated ISR activation, and TLR4 regulated the accumulation of mitochondrial reactive oxygen species (mtROS) and double-stranded RNA (dsRNA). Downregulating the level of mtROS reduced the amount of dsRNA and ISR activation. Deactivating the ISR or blocking CCL2/7 release alleviated inflammation and the progression of IDD in vivo. Moreover, MΦ infiltration and IDD were inhibited in CCR2-knockout mice. In conclusion, this study highlights the critical role of TLR4/mtROS/dsRNA axis-mediated ISR activation in the production of CCL2/7 and the progression of IDD, which provides promising therapeutic strategies for discogenic LBP.

Alteration of functionality and differentiation directed by changing gene expression patterns in myeloid-derived suppressor cells (MDSCs) in tumor microenvironment and bone marrow through early to terminal phase of tumor progression.

Myeloid-derived suppressor cells are heterogenous immature myeloid lineage cells that can differentiate into neutrophils, monocytes, and dendritic cells as well. These cells have been characterized to have potent immunosuppressive capacity in neoplasia and a neoplastic chronic inflammatory microenvironment. Increased accumulation of myeloid-derived suppressor cells was reported with poor clinical outcomes in patients. They support neoplastic progression by abrogating antitumor immunity through inhibition of lymphocyte functions and directly by facilitating tumor development. Yet the shifting genetic signatures of this myeloid lineage cell toward immunosuppressive functionality in progressive tumor development remain elusive. We have attempted to identify the gene expression profile using lineage-specific markers of these unique myeloid lineage cells in a tumor microenvironment and bone marrow using a liquid transplantable mice tumor model to trace the changing influence of the tumor microenvironment on myeloid-derived suppressor cells. We analyzed the phenotype, functional shift, suppressive activity, differentiation status, and microarray-based gene expression profile of CD11b+Gr1+ lineage-specific cells isolated from the tumor microenvironment and bone marrow of 4 stages of tumor-bearing mice and compared them with control counterparts. Our analysis of differentially expressed genes of myeloid-derived suppressor cells isolated from bone marrow and the tumor microenvironment reveals unique gene expression patterns in the bone marrow and tumor microenvironment-derived myeloid-derived suppressor cells. It also suggests T-cell suppressive activity of myeloid-derived suppressor cells progressively increases toward the mid-to-late phase of the tumor and a significant differentiation bias of tumor site myeloid-derived suppressor cells toward macrophages, even in the presence of differentiating agents, indicating potential molecular characteristics of myeloid-derived suppressor cells in different stages of the tumor that can emerge as an intervention target.

Role and mechanism of macrophage-mediated osteoimmune in osteonecrosis of the femoral head

To summarize the research progress on the role of macrophage-mediated osteoimmune in osteonecrosis of the femoral head (ONFH) and its mechanisms. Recent studies on the role and mechanism of macrophage-mediated osteoimmune in ONFH at home and abroad were extensively reviewed. The classification and function of macrophages were summarized, the osteoimmune regulation of macrophages on chronic inflammation in ONFH was summarized, and the pathophysiological mechanism of osteonecrosis was expounded from the perspective of osteoimmune, which provided new ideas for the treatment of ONFH. Macrophages are important immune cells involved in inflammatory response, which can differentiate into classically activated type (M1) and alternatively activated type (M2), and play specific functions to participate in and regulate the physiological and pathological processes of the body. Studies have shown that bone immune imbalance mediated by macrophages can cause local chronic inflammation and lead to the occurrence and development of ONFH. Therefore, regulating macrophage polarization is a potential ONFH treatment strategy. In chronic inflammatory microenvironment, inhibiting macrophage polarization to M1 can promote local inflammatory dissipation and effectively delay the progression of ONFH; regulating macrophage polarization to M2 can build a local osteoimmune microenvironment conducive to bone repair, which is helpful to necrotic tissue regeneration and repair to a certain extent. At present, it has been confirmed that macrophage-mediated chronic inflammatory immune microenvironment is an important mechanism for the occurrence and development of ONFH. It is necessary to study the subtypes of immune cells in ONFH, the interaction between immune cells and macrophages, and the interaction between various immune cells and macrophages, which is beneficial to the development of potential therapeutic methods for ONFH.

Plasma cells in human pancreatic ductal adenocarcinoma secrete antibodies against self-antigens.

Intratumoral B cell responses are associated with more favorable clinical outcomes in human pancreatic ductal adenocarcinoma (PDAC). However, the antigens driving these B cell responses are largely unknown. We sought to discover these antigens by using single-cell RNA sequencing (scRNA-Seq) and immunoglobulin (Ig) sequencing of tumor-infiltrating immune cells from 7 primary PDAC samples. We identified activated T and B cell responses and evidence of germinal center reactions. Ig sequencing identified plasma cell (PC) clones expressing isotype-switched and hypermutated Igs, suggesting the occurrence of T cell-dependent B cell responses. We assessed the reactivity of 41 recombinant antibodies that represented the products of 235 PCs and 12 B cells toward multiple cell lines and PDAC tissues and observed frequent staining of intracellular self-antigens. Three of these antigens were identified: the filamentous actin (F-actin), the nucleic protein RuvB like AAA ATPase 2 (RUVBL2), and the mitochondrial protein heat shock protein family D (Hsp60) member 1 (HSPD1). Antibody titers against F-actin and HSPD1 were substantially elevated in the plasma of patients with PDAC compared with healthy donors. Thus, PCs in PDAC produce autoantibodies reacting with intracellular self-antigens, which may result from promotion of preexisting, autoreactive B cell responses. These observations indicate the chronic inflammatory microenvironment of PDAC can support the adaptive immune response.

Mutant p53 Drives the Development of Myelodysplastic Syndromes Via Dysregulating Pre-mRNA Splicing in Hematopoietic Stem and Progenitor Cells

Despite the clinical importance of TP53 mutations, to date there have been no studies on the functional impact of TP53 mutations on the initiation and progression of MDS. We found that heterozygous p53 mutant mice ( p53R248W/+) show extended survival and died within 15-20 months after birth. p53 mutant mice had hypercellular bone marrow and displayed cytopenia, thrombocytopenia, and anemia. Approximately 60% of p53R248W/+ mice developed MDS based upon pathological analysis of bone marrow (BM) and peripheral blood smears, while the remaining p53R248W/+ mice developed lymphoma and sarcoma. We further showed that mutant p53-driven MDS are transplantable. Thus, we have generated a mouse model of MDS that has some features of human MDS with TP53 mutations. To understand how mutant p53 drives MDS development, we performed RNA-seq studies to compare gene expression in hematopoietic stem and progenitor cells (HSPCs). GSEA analysis revealed that spliceosome genes were significantly downregulated in middle-aged p53 R248W/+ HSPCs compared to age-matched p53 +/+ HSPCs. We confirmed that the expression of splicing factors, such as Prpf3 and Prpf4, was significantly downregulated in middle-aged p53 R248W/+ HSPCs. We conducted alternative splicing analysis utilizing MISO (Mixture of Isoforms) algorithm to identify differences in exon inclusion ratio between WT and mutant HSPCs. We observed differential splicing of all classes of alternative splicing events, including Cassette Exons (CE), Competing 5′ and 3′ splice sites (A5' or A3'SS), Mutually Exclusive Exons (MXE), and Retained Introns (RI) in p53 R248W/+ cells compared to that of the WT HSPCs. Notably, we found that murine p53 mutant HSPCs exhibited aberrant splicing of key regulators of NFκBactivation, such as USP15. USP15 overexpression promotes NFκB expression through inhibiting its ubiquitination, whereas NFκB promotes USP15 expression. p53 mutant HSPCs tend to skip exon 7 and express high levels of short isoform of Usp15. The short isoform of Usp15, but not the long isoform of Usp15, activates NFκB in HSPCs, manifested by increased phosphorylation of p65. To determine the impact of mutant p53 on pre-mRNA splicing in human HSPCs, we ectopically expressed GFP or p53 R248W in human cord blood CD34 + cells and performed RNA-seq in transduced cells (GFP +). Human HSPCs expressing mutant p53 displayed alterations in pre-mRNA splicing compared to HSPCs expressing GFP. We found that human HSPCs expressing mutant p53 display aberrant splicing in key regulator of NFκB such as IKBKE (Inhibitor of nuclear factor kappa-B kinase subunit epsilon). Human HSPCs expressing mutant p53 tend to include exon 7 and express high levels of long isoform of IKBKE. The long isoform of IKBKE, but not the short isoform of IKBKE, activates NFκB in human HSPCs. Many proinflammatory cytokine genes are NFκB targets and we observed increased levels of pro-inflammatory cytokines, including IL-1β and IL-6, in the BM of middle-aged p53 mutant mice. Notably, we observed increased levels of IL-1β and IL-6 in the BM of MDS or AML patients with TP53 mutations. TP53 mutations co-occur with splicing factor mutations in MDS. To determine whether TP53 and SRSF2 mutations cooperate in pathogenesis of MDS, we have generated p53 R248W/+SRSF2 P95H/+ mice. We found that the survival of recipient mice repopulated with p53 R248W/+SRSF2 P95H/+ BM cells was significantly decreased compared to recipients repopulated with WT, p53 R248W/+, or SRSF2 P95H/+ BM cells. All recipient mice repopulated with p53 R248W/+SRSF2 P95H/+ BM cells died within 6 months and developed MDS or leukemia. Thus, we demonstrate that TP53 and SRSF2 mutations cooperate in MDS or leukemia development. In summary, we discovered that mutant p53 dysregulates pre-mRNA splicing in key regulators of inflammatory response during aging, thereby generating a chronic inflammatory microenvironment to drive MDS pathogenesis.

A Novel Cytochrome P450 2E1 Inhibitor Q11 Is Effective on Lung Cancer via Regulation of the Inflammatory Microenvironment.

Lung cancer is the leading cause of death among all cancers. A persistent chronic inflammatory microenvironment is highly correlated with lung cancer. However, there are no anti-inflammatory agents effective against lung cancer. Cytochrome P450 2E1 (CYP2E1) plays an important role in the inflammatory response. Here, it is found that CYP2E1 is significantly higher in the peritumoral tissue of non-small cell lung cancer (NSCLC) patients and lung tumor growth is significantly impeded in Cyp2e1-/- mice. The novel CYP2E1 inhibitor Q11, 1-(4-methyl-5-thialzolyl) ethenone, is effective in the treatment of lung cancer in mice, which can inhibit cancer cells by changing macrophage polarization rather than directly act on the cancer cells. It is also clarify that the benefit of Q11 may associated with the IL-6/STAT3 and MAPK/ERK pathways. The data demonstrate that CYP2E1 may be a novel inflammatory target and that Q11 is effective on lung cancer by regulation of the inflammatory microenvironment. These findings provide a molecular basis for targeting CYP2E1 and illustrate the potential druggability of the CYP2E1 inhibitor Q11.

Cytokines as drivers: Unraveling the mechanisms of epithelial-mesenchymal transition in COVID-19 lung fibrosis

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), like other viruses, can induce proliferation of myofibroblasts and even lead to fibrosis in the lung. Epithelial-mesenchymal transition (EMT) is thought to play an essential role in the pathogenesis of Coronavirus disease 19 (COVID-19). EMT is originally a critical process that regulates the development of different tissues in the embryo, but in inflammatory situations, EMT tries to be activated again to control inflammation or even heal inflammatory damage. However, in pathological situations, such as chronic viral infections (e.g., COVID-19) or pulmonary fibrosis initiation, this benign healing transforms into sinister nature, pushing the lung into the fibrotic process. Notably, the cytokines released by inflammatory cells and the chronic inflammatory microenvironment shared by fibrotic cells promote each other as critical factors in the induction of pathological EMT. In the induction of SARS-CoV-2 virus, cytokines are an essential mediator of EMT transformation, and a summary of whether COVID-19 patients, during the infection phase, have many persistent inflammatory mediators (cytokines) that are a causative factor of EMT has not yet appeared.The following common signaling drivers, including Transforming growth factor beta (TGF-β), cytokines, Notch signaling pathway, Wnt and hypoxia signaling pathways, drive the regulation of EMT. In this review, we will focus on 3 key EMT signaling pathways: TGF-β, Leucine zipper transcription factor like 1 (LZTFL1) and the common interleukin family expressed in the lung. TGF-β-induced SNAIL and LZTFL1 were identified as regulatory EMT in COVID-19. For cytokines, the interleukin family is a common inducer of EMT and plays an essential role in the formation of the microenvironment of fibrosis. We sought to demonstrate that cytokines act as "communicators" and build the "microenvironment" of fibrosis together with EMT as a "bridge" to induce EMT in fibrosis. The mechanisms utilized by these two pathways could serve as templates for other mesenchymal transformations and provide new potential therapeutic targets.

Multifunctional annulus fibrosus matrix prevents disc-related pain via inhibiting neuroinflammation and sensitization

Chronic low back pain mainly attributed to intervertebral disc (IVD) degeneration. Endogenous damage-associated molecular patterns (DAMPs) in the injured IVD, particularly mitochondria-derived nucleic acid molecules (CpG DNA), play a primary role in the inflammatory responses in macrophages. M1-type macrophages form a chronic inflammatory microenvironment by releasing pro-inflammatory factors and nerve growth factor (NGF) that induce nerve growth into the inner annulus fibrosus, resulting in persistent hyperalgesia. We fabricated an amphiphilic polycarbonate that naturally forms cationic nanoparticles (cNP) in aqueous solutions, with the hydrophobic core loaded with TrkA-IN-1, an antagonist against the NGF receptor (TrkA). The drug delivery nanoparticles were denoted as TI-cNP. TrkA-IN-1 and TI-cNP were added to the decellularized annulus fibrosus matrix (DAF) hydrogel to form hybrid hydrogels, denoted as TI-DAF and TI-cNP-DAF, respectively. As a result, TrkA-IN-1 showed a delayed release profile both in TI-DAF and TI-cNP-DAF. Each mole of cNP could bind approximately 3 mol of CpG DNA to inhibit inflammation. cNP-DAF and TI-cNP-DAF significantly inhibited the M1 phenotype induced by CpG DNA. TI-DAF and TI-cNP-DAF reduced neurite branching and axon length, and inhibited the expression of neurogenic mediators (CGRP and substance P) in the presence of NGF. Besides, TI-cNP-DAF relieved mechanical hyperalgesia, reduced CGRP and substance P expression in the dorsal root ganglion, and downregulated GFAP and c-FOS signaling in the spinal cord in the rat disc herniation model. Summarily, TI-cNP-DAF, a novel composite IVD hydrogel, efficiently mediated the inflammatory environment, inhibited nerve ingrowth and sensitization, and could be clinically applied for treating discogenic pain. Statement of significanceDiscogenic lower back pain, related to intervertebral disc degeneration (IDD), imposes a tremendous health and economic burden globally. M1-type macrophages release pro-inflammatory factors and nerve growth factor (NGF) that induce nerve growth into the inner annulus fibrosus, resulting in persistent hyperalgesia and discogenic pain. Reconstructing matrix integrity and modulating the inflammatory microenvironment are promising strategies for preventing the ingrowth and activation of neurites. The TI-cNP-DAF hydrogel recovers tissue integrity, alleviates inflammation, and delivers the TrkA antagonist to inhibit the activity of NGF, thus restraining hyperinnervation and nociceptive input. Due to its simple production process, injectability, and acellular strategy, the hydrogel is operable and holds great potential for treating discogenic lower back pain.

Sulforaphane Reduces the Chronic Inflammatory Immune Response of Human Dendritic Cells.

Sulforaphane (SFN) is an isothiocyanate of vegetable origin with potent antioxidant and immunomodulatory properties. The characterization of its pleiotropic activity in human dendritic cells (DCs) is poorly summarized. The aim of this work was to study the immunomodulatory power of SFN in response to an inflammatory microenvironment on human monocyte-derived DCs (moDCs). We studied the immunological response induced by SFN. Apoptosis and autophagy assays were performed using flow cytometry on moDCs and a cancer cell line (THP-1). These included moDC maturation, lymphocyte proliferation and cytokine production under different experimental conditions. We investigated whether these results were associated with an inflammatory microenvironment induced by lipopolysaccharides (LPSs). Our results demonstrated that SFN could interact with moDCs, significantly reducing the autophagy process and enhancing apoptosis similarly to cancer cell line THP-1 cells in a chronic inflammatory microenvironment. Under chronic inflammation, SFN modulated the phenotypical characteristics of moDCs, reducing the expression of all markers (CD80, CD83, CD86, HLA-DR and PD-L1). SFN significantly reduced the Th2 proliferative response, with a decrease in the IL-9 and IL-13 levels. Although we did not observe any changes in the regulatory proliferative response, we noted an increase in the IL-10 levels. These findings demonstrate that SFN exerts protective effects against LPS-induced inflammation via the modulation of moDCs/T cells towards a regulatory profile. SFN may be a potential candidate for the treatment of pathologies with an inflammatory profile.

Eicosapentaenoic acid supplementation modulates the osteoblast/osteoclast balance in inflammatory environments and protects against estrogen deficiency-induced bone loss in mice

An imbalance of osteoblasts (OBs) and osteoclasts (OCs) in a chronic inflammatory microenvironment is an important pathological factor leading to osteoporosis. Eicosapentaenoic acid (EPA) has been shown to suppress inflammation in macrophages and adipocytes. However, the effect of EPA on OBs and OCs has yet to be fully elucidated. We explored the roles of EPA in the differentiation of OBs and OCs, as well as the coupling between OBs and OCs in an inflammatory microenvironment. The effects of EPA on estrogen deficiency-induced osteoporosis were also evaluated. Mouse bone marrow mesenchymal stem cells (mBMSCs) and mouse bone marrow-derived macrophages (mBMMs) were used for invitro OBs and OCs differentiation. TNF-α was used to create an inflammatory microenvironment. We examined the effects of EPA on osteoblastogenesis in the absence or presence of TNF-α and collect OBs' culture medium as the conditioned medium (CM). Then we examined the effects of EPA and CM on RANKL-induced osteoclastogenesis. The invivo effects of EPA were determined using an ovariectomized (OVX) mouse model treated with EPA or vehicle. High-dose EPA was shown to promote osteoblastogenesis in an inflammatory environment invitro, as well as upregulate expression of OBs-specific proteins and genes. ARS and ALP staining also showed that high-dose EPA-treated groups restored mBMSCs' impaired osteogenic capacity caused by TNFa. Mechanistically, EPA suppressed the NF-κB pathway activated by TNF-α in mBMSCs and rescued TNF-α-mediated inhibition of osteoblastogenesis. EPA was also shown to inhibit expression of RANKL and decrease the RANKL/OPG ratio in OBs in an inflammatory environment. CM from TNF-α-stimulated OBs promoted osteoclastogenesis of mBMMs; EPA-treated CM prevented this. In the OVX mouse model, EPA supplementation prevented bone loss in an estrogen deficiency-induced inflammatory environment. EPA was demonstrated for the first time to restore mBMSCs' impaired osteogenic capacity caused by TNFa-induced inflammation and rescue the OBs/OCs balance via regulation of RANKL and OPG expression in OBs. EPA showed a remarkable ability to prevent bone loss in OVX mice, suggesting a potential application of EPA in postmenopausal osteoporosis.

Plaque Macrophage‐Targeting Nanosystems with Cooperative Co‐Regulation of ROS and TRAF6 for Stabilization of Atherosclerotic Plaques

AbstractChronic inflammatory microenvironment is the predominant milieu that promotes the progression of atherosclerosis (AS). However, targeted regulation of the chronic proinflammatory milieu still needs to be improved. In this study, macrophage‐targeting nanosystems composed of 37pA peptide embedded–Pt lipid nanoparticles (37pA‐PtLNP) and tumor necrosis factor‐associated factor 6 (TRAF6) inhibitor (6877002)‐loaded poly(ε‐caprolactone)‐b‐polyethylene glycol‐b‐poly(ε‐caprolactone) (PCEC) are constructed with 37pA peptide embedded–lipid coating (37pA‐LNP/6877002), to stabilize atherosclerotic lesions. The cooperative regulation effects of these nanosystems in achieving reactive oxygen species (ROS) scavenging and inflammatory signaling inhibition are investigated. 37pA‐PtLNP effectively scavenges several ROS, however, also promotes the expression of iNOS. The introduction of 37pA‐LNP/6877002 inhibits the activities of TRAF6, a downstream intracellular factor of the CD40L‐CD40‐TRAF6 axis, to decrease the proportion of the proinflammatory M1 macrophage phenotype, which is further downregulated by combined treatment with 37pA‐PtLNP. The combination of 37pA‐PtLNP and 37pA‐LNP/6877002 not only counteracts 37pA‐PtLNP–induced iNOS upregulation but also alleviates the chronic inflammatory microenvironment by reducing the expression of proinflammatory cytokines and chemokines. The anti‐AS efficacy in vivo on ApoE−/− mice further demonstrates that the combination of 37pA‐PtLNP and 37pA‐LNP/6877002 targetedly modulates the atherosclerotic plaque microenvironment, achieving stabilization of lesions with minimal progression. This study provides a promising strategy for AS management.

Coicis Semen for the treatment of malignant tumors of the female reproductive system: A review of traditional Chinese medicinal uses, phytochemistry, pharmacokinetics, and pharmacodynamics.

Coicis Semen is an important food product and traditional Chinese medicine (TCM) derived from the dried and mature seeds of Coix lacryma-jobi L.var.ma-yuen (Roman.) Stapf. An increasing number of studies have investigated its use, either alone or in combination with other botanical drugs, to treat female reproductive system malignancies, and its pharmacological effects have been confirmed clinically. This review aims to provide an overview of Coicis Semen's historical role in treating female reproductive system malignancies based on TCM theory, to summarize clinical trials results, and to analyze information pertaining to the main phytochemical components, pharmacokinetics, related anti-cancer pharmacological effects, and toxicology of Coicis Semen. Information on Coicis Semen was collected from internationally accepted scientific databases. Seventy-four clinical trials were identified that used Coicis Semen in combination with other Chinese medicine to treat female reproductive system malignancies, most of which demonstrated good anti-tumor efficacy and few adverse reactions. To date, more than 80 individual compounds have been isolated from this botanical drug. In terms of anti-tumor effects, Coix seed oil has been studied the most. Pharmacokinetic data suggest that the active ingredients in Coicis Semen are widely distributed after administration, and Coicis Semen and its active compounds play a beneficial role in treating female reproductive system malignancies. Mechanistically, the anti-cancer effects may be related to inhibition of tumor cell proliferation and promotion of apoptosis, inhibition of tumor angiogenesis, suppression of the chronic inflammatory microenvironment of tumors, modulation of immune function, and regulation of the female reproductive system. Most acute toxicity and genotoxicity studies have shown that Coicis Semen is non-toxic. However, the existing studies have many limitations, and the future research direction should emphasize 1) the relationship between drug concentration and pharmacological action as well as toxicity; 2) the structural modification or the synthesis of analogues led by the active ingredients of Coicis Semen to enhance pharmacological activities and bioavailability; 3) accurately revealing the anti-cancer pharmacological effects of Coicis Semen and its compounds through multi-omics technology. We hope that this review can determine future directions and inform novel drug development for treating female reproductive malignancies.

Potential Role of the Fragile Histidine Triad in Cancer Evo-Dev.

Cancer development follows an evolutionary pattern of "mutation-selection-adaptation" detailed by Cancer Evolution and Development (Cancer Evo-Dev), a theory that represents a process of accumulating somatic mutations due to the imbalance between the mutation-promoting force and the mutation-repairing force and retro-differentiation of the mutant cells to cancer initiation cells in a chronic inflammatory microenvironment. The fragile histidine triad (FHIT) gene is a tumor suppressor gene whose expression is often reduced or inactivated in precancerous lesions during chronic inflammation or virus-induced replicative stress. Here, we summarize evidence regarding the mechanisms by which the FHIT is inactivated in cancer, including the loss of heterozygosity and the promoter methylation, and characterizes the role of the FHIT in bridging macroevolution and microevolution and in facilitating retro-differentiation during cancer evolution and development. It is suggested that decreased FHIT expression is involved in several critical steps of Cancer Evo-Dev. Future research needs to focus on the role and mechanisms of the FHIT in promoting the transformation of pre-cancerous lesions into cancer.