Epigenetic regulation of chemokine (CC-motif) ligand 2 in inflammatory diseases

Identification of critical genes and metabolic pathways in rheumatoid arthritis and osteoporosis toward drug repurposing

BACKGROUND

Rheumatoid arthritis (RA) and osteoporosis (OP) are considered to be complex diseases. In recent studies, a positive association between RA and OP has been reported triggering growing research interest. This study aims to investigate the drugs related to critical genes in RA and OP, using bioinformatics approaches, toward drug repurposing.

METHOD

RA and OP genes were identified. The RA-OP PPI network was constructed and analyzed using the STRING and Cytoscape, respectively. Hub genes and modules were extracted and enriched Gene Ontology, through the WebGestalt and g:Profiler. The identification of the drugs related to critical genes using the DGIDB, and extracted the miRNAs using miRWalk and miRNet.

RESULTS

By network clustering, five significant modules were obtained that have important roles in the immune system. IL6, TNF, IL1B, STAT3, TGFB1, TP53, HIF1A, CCL2, IL10, and MMP9 were found as the top 10 hub genes in the RA-OP network. Hub genes were shown to have implications in inflammatory response, significant functions in cytokine receptor binding, and localized mostly in extracellular space. By investigating the drugs related to hub genes, 16 drugs were identified as repurposing candidate drugs. The 10 drugs included Hydroxychloroquine, Infliximab, Adalimumab, Etanercept, Certolizumab, Cyclosporine, Diacerein, Gevokizumab, Canakinumab, and Olokizumab proposed for OP. Also, six drugs including Pirfenidone, Pentoxifylline, Vadimezan, Rilonacept, Metelimumab, and Siltuximab have important roles in inflammatory control and were proposed for both RA and OP.

CONCLUSIONS

The results of the present study can provide novel insights into the pathogenesis and treatment of RA and OP.

Harmonizing hope: navigating the osteoarthritis melody through the CCL2/CCR2 axis for innovative therapeutic avenues

Osteoarthritis (OA) is characterized by a complex interplay of molecular signals orchestrated by the CCL2/CCR2 axis. The pathogenesis of OA has been revealed to be influenced by a multifaceted effect of CCL2/CCR2 signaling on inflammation, cartilage degradation, and joint homeostasis. The CCL2/CCR2 axis promotes immune cell recruitment and tips the balance toward degeneration by influencing chondrocyte behavior. Insights into these intricate pathways will offer novel therapeutic approaches, paving the way for targeted interventions that may redefine OA management in the future. This review article explores the molecular symphony through the lens of the CCL2/CCR2 axis, providing a harmonious blend of current knowledge and future directions on OA treatment. Furthermore, in this study, through a meticulous review of recent research, the key players and molecular mechanisms that amplify the catabolic cascade within the joint microenvironment are identified, and therapeutic approaches to targeting the CCL2/CCR axis are discussed.

SRGN promotes macrophage recruitment through CCL3 in osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a degenerative disease that affects synovial joints and leads to significant pain and disability, particularly in older adults. Infiltration of macrophages plays a key role in the progression of OA. However, the mechanisms underlying macrophage recruitment in OA are not fully understood.

METHODS

The Serglycin (SRGN) expression pattern was analyzed, along with its association with macrophage infiltration in OA, using bioinformatic methods. SRGN expression in chondrocytes was altered by small interfering RNA (siRNA) and plasmids. Conditioned media (CM) was obtained from transfected chondrocytes to establish a co-culture model of chondrocytes and THP-1 derived macrophages. The impact of SRGN on macrophage recruitment was evaluated using a transwell assay. Furthermore, the regulatory effect of SRGN on CCL3 was validated through qPCR, WB, and ELISA experiments.

RESULTS

In OA patients, the upregulation of SRGN positively correlated with K-L grade and macrophage infiltration. It was found that SRGN expression and secretion were up-regulated in OA and that it can promote macrophage migration in vitro. Further investigation showed that SRGN affects macrophage migration by regulating the expression of CCL3.

CONCLUSION

SRGN in chondrocytes plays a role in promoting the recruitment of THP-1 derived macrophages in vitro by regulating production of CCL3.

Decoding the role of the CCL2/CCR2 axis in Alzheimer's disease and innovating therapeutic approaches: Keeping All options open

Alzheimer's disease (AD), as a neurodegenerative disorder, distresses the elderly in large numbers and is characterized by β-amyloid (Aβ) accumulation, elevated tau protein levels, and chronic inflammation. The brain's immune system is aided by microglia and astrocytes, which produce chemokines and cytokines. Nevertheless, dysregulated expression can cause hyperinflammation and lead to neurodegeneration. CCL2/CCR2 chemokines are implicated in neurodegenerative diseases exacerbating. Inflicting damage on nerves and central nervous system (CNS) cells is the function of this axis, which recruits and migrates immune cells, including monocytes and macrophages. It has been shown that targeting the CCL2/CCR2 axis may be a therapeutic option for inflammatory diseases. Using the current knowledge about the involvement of the CCL2/CCR2 axis in the immunopathogenesis of AD, this comprehensive review synthesizes existing information. It also explores potential therapeutic options, including modulation of the CCL2/CCR2 axis as a possible strategy in AD.

Inflammation in the Peripheral Nervous System after Injury

Nerve injury is a common condition that occurs as a result of trauma, iatrogenic injury, or long-lasting stimulation. Unlike the central nervous system (CNS), the peripheral nervous system (PNS) has a strong capacity for self-repair and regeneration. Peripheral nerve injury results in the degeneration of distal axons and myelin sheaths. Macrophages and Schwann cells (SCs) can phagocytose damaged cells. Wallerian degeneration (WD) makes the whole axon structure degenerate, creating a favorable regenerative environment for new axons. After nerve injury, macrophages, neutrophils and other cells are mobilized and recruited to the injury site to phagocytose necrotic cells and myelin debris. Pro-inflammatory and anti-inflammatory factors involved in the inflammatory response provide a favorable microenvironment for peripheral nerve regeneration and regulate the effects of inflammation on the body through relevant signaling pathways. Previously, inflammation was thought to be detrimental to the body, but further research has shown that appropriate inflammation promotes nerve regeneration, axon regeneration, and myelin formation. On the contrary, excessive inflammation can cause nerve tissue damage and pathological changes, and even lead to neurological diseases. Therefore, after nerve injury, various cells in the body interact with cytokines and chemokines to promote peripheral nerve repair and regeneration by inhibiting the negative effects of inflammation and harnessing the positive effects of inflammation in specific ways and at specific times. Understanding the interaction between neuroinflammation and nerve regeneration provides several therapeutic ideas to improve the inflammatory microenvironment and promote nerve regeneration.

MCP-1 controls IL-17-promoted monocyte migration and M1 polarization in osteoarthritis

Osteoarthritis (OA) is a low-grade inflammatory joint illness in which monocytes migrate and infiltrate synovial tissue, differentiating into the pro-inflammatory M1 macrophage phenotype. IL-17 is a proinflammatory mediator principally generated by Th17 cells, which is elevated in OA patients; nevertheless, investigators have yet to elucidate the function of IL-17 in M1 polarization during OA development. Our analysis of clinical tissues and results from the open online dataset discovered that the level of M1 macrophage markers is elevated in human OA tissue samples than in normal tissue. High-throughput screening demonstrated that MCP-1 is a potential candidate factor after IL-17 treatment in OA synovial fibroblasts (OASFs). Immunohistochemistry data revealed that the level of MCP-1 is higher in humans and mice with OA than in normal tissues. IL-17 stimulation facilitates MCP-1-dependent macrophage polarization to the M1 phenotype. It also appears that IL-17 enhances MCP-1 synthesis in human OASFs, enhancing monocyte migration via the JAK and STAT3 signaling cascades. Our findings indicate the IL-17/MCP-1 axis as a novel strategy for the remedy of OA.

The occurrence and development of induced pluripotent stem cells

The ectopic expression of four transcription factors, Oct3/4, Sox2, Klf4, and c-Myc (OSKM), known as "Yamanaka factors," can reprogram or stimulate the production of induced pluripotent stem cells (iPSCs). Although OSKM is still the gold standard, there are multiple ways to reprogram cells into iPSCs. In recent years, significant progress has been made in improving the efficiency of this technology. Ten years after the first report was published, human pluripotent stem cells have gradually been applied in clinical settings, including disease modeling, cell therapy, new drug development, and cell derivation. Here, we provide a review of the discovery of iPSCs and their applications in disease and development.

Network pharmacology-based strategy combined with molecular docking to explore the potential mechanism of agarwood against recurrent aphthous stomatitis

To explore the antiinflammatory mechanism of agarwood on recurrent aphthous stomatitis (RAS). RAS is the most common mucosal disease in the oral cavity. The clinical application of traditional Chinese medicine found that agarwood has significant curative effect on peptic ulcer, but the effect and mechanism of agarwood on RAS remain unclear. This study is intended to predict the potential antiinflammatory mechanisms by which agarwood acts on RAS through network pharmacology and molecular docking. TCMSP database was used to screen the active components of agarwood. RAS targets were screened in Genecards, DisGeNET, and OMIM database. Venny, an online tool, screens for interacting genes between the two. Cytoscape software was used to construct the gene regulation map of active compounds target of agarwood. String Database building protein-protein interaction network. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathways were enriched in DAVID database. The key active ingredients and core targets were further verified by molecular docking. There were 9 effective compounds and 186 target genes in agarwood; RAS has 793 target genes. There were 41 interacting genes between agarwood and RAS. Interleukin 6, tumor necrosis factor, interleukin 1 beta, and cellular component motif ligand 2 may be key targets. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses predicted multiple pathways associated with RAS. Molecular docking results showed that the active compounds of agarwood combined well and stably with the target. The Chinese herbal medicine agarwood can relieve the inflammation of RAS through multiple targets and various ways. Its active compounds may be nominated as candidates for antiinflammatory drugs of RAS.

Role of MCP-1 as an inflammatory biomarker in nephropathy

The Monocyte chemoattractant protein-1 (MCP-1), also referred to as chemokine ligand 2 (CCL2), belongs to the extensive chemokine family and serves as a crucial mediator of innate immunity and tissue inflammation. It has a notable impact on inflammatory conditions affecting the kidneys. Upon binding to its receptor, MCP-1 can induce lymphocytes and NK cells' homing, migration, activation, differentiation, and development while promoting monocytes' and macrophages' infiltration, thereby facilitating kidney disease-related inflammation. As a biomarker for kidney disease, MCP-1 has made notable advancements in primary kidney diseases such as crescentic glomerulonephritis, chronic glomerulonephritis, primary glomerulopathy, idiopathic proteinuria glomerulopathy, acute kidney injury; secondary kidney diseases like diabetic nephropathy and lupus nephritis; hereditary kidney diseases including autosomal dominant polycystic kidney disease and sickle cell kidney disease. MCP-1 not only predicts the occurrence, progression, prognosis of the disease but is also closely associated with the severity and stage of nephropathy. When renal tissue is stimulated or experiences significant damage, the expression of MCP-1 increases, demonstrating a direct correlation with the severity of renal injury.