The potential role of miRNA in regulating macrophage polarization

Macrophage polarization regulates the pathogenesis and progression of autoimmune diseases

Macrophages are integral components of the innate immune system, present in nearly all tissues and organs throughout the body. They exhibit a high degree of plasticity and heterogeneity, participating in immune responses to maintain immune homeostasis. When the immune system loses tolerance, macrophages rapidly proliferate and polarize in response to various signaling pathways within a disrupted microenvironment. The direction of macrophage polarization can be regulated by a variety of factors, including transcription factors, non-coding RNAs, and metabolic reprogramming. Autoimmune diseases arise from the immune system's activation against host cells, with macrophage polarization playing a critical role in the pathogenesis of numerous chronic inflammatory and autoimmune conditions, such as rheumatoid arthritis, systemic lupus erythematosus, immune thrombocytopenic purpura, and type 1 diabetes. Consequently, elucidating the molecular mechanisms underlying macrophage development and function presents opportunities for the development of novel therapeutic targets. This review outlines the functions of macrophage polarization in prevalent autoimmune diseases and the underlying mechanisms involved. Furthermore, we discuss the immunotherapeutic potential of targeting macrophage polarization and highlight the characteristics and recent advancements of promising therapeutic targets. Our aim is to inspire further strategies to restore macrophage balance in preventing and treating autoimmune diseases.

Targeting Hsp70 Immunosuppressive Signaling Axis with Lipid Nanovesicles: A Novel Approach to Treat Pancreatic Cancer

BACKGROUND

Despite many efforts to effectively treat PDAC, PDAC carries one of the highest mortality rates of all major cancers. Thus, there is a critical unmet need to develop novel approaches to improve the clinical outcome of PDAC. It is well known that many cancers, including PDAC, generate a local TME that allows cancer to escape normal immune surveillance. Phosphatidylserine (PS), a negatively charged phospholipid that is abundant on the cancer cell membrane and with known actions to promote the secretion of immunomodulatory proteins, may provide a mechanism to regulate the TME. This study explored that possibility.

METHODS

MΦ differentiation and polarization were assessed by Western blotting and flow cytometric approaches. PS exposure and surface markers were analyzed by flow cytometry. Protein-protein and protein-lipid interactions were analyzed by immunofluorescence and enzyme-linked immunosorbent assay (ELISA). Phospholipid and SapC-DOPG treatment were employed to assess target protein functions in MΦ polarization, tumor growth, and survival in subcutaneous and orthotopic tumor models. The PK-PD and safety of SapC-DOPG were tested on orthotopic mouse models.

RESULTS

Our studies show that PDAC secretes Hsp70 that stimulates the MΦ polarization to the immunosuppressive M2 phenotype. We found that high surface PS on cancer cells correlates with increased secretion of Hsp70 and is associated with higher MΦ differentiation activity in vitro and in vivo. Furthermore, blocking cancer cell-secreted Hsp70 with SapC-DOPG reverses the immune suppression and reduces tumor growth.

CONCLUSIONS

These preclinical results reveal a novel immunotherapeutic approach to potentially improve the outcome of PDAC treatment in humans.

Improving the Wound Healing Process: Pivotal role of Mesenchymal stromal/stem Cells and Immune Cells

Wound healing, a physiological process, involves several different types of cells, from immune cells to non-immune cells, including mesenchymal stromal/stem cells (MSC), and their interactions. Immune cells including macrophages, neutrophils, dendritic cells (DC), innate lymphoid cells (ILC), natural killer (NK) cells, and B and T lymphocytes participate in wound healing by secreting various mediators and interacting with other cells. MSCs, as self-renewing, fast proliferating, and multipotent stromal/stem cells, are found in a wide variety of tissues and critically involved in different phases of wound healing by secreting various molecules that help to improve tissue healing and regeneration. In this review, first, we described the four main phases of wound healing, second, we reviewed the function of MSCs, MSC secretome and immune cells in improving the progress of wound repair (mainly focusing on skin wound healing), third, we explained the immune cells/MSCs interactions in the process of wound healing and regeneration, and finally, we introduce clinical applications of MSCs to improve the process of wound healing.

Biomimetic MOF Nanocarrier-Mediated Synergistic Delivery of Mitochondria and Anti-Inflammatory miRNA to Alleviate Acute Lung Injury

Acute lung injury (ALI) is a clinically critical disease characterized by overwhelming inflammatory response and significant tissue damage with no specific treatment available currently. As a key player in the pathogenesis of ALI, macrophages are aberrantly activated and polarize toward the pro-inflammatory phenotypes, leading to overzealous inflammation and lung injury. Mitochondria is recognized as a crucial signaling hub governing macrophage function and polarization, deregulation of which is causatively related with defective metabolism of macrophages, deregulated inflammation, and hence ALI. Herein, an inflammation-responsive, biomimetic metal-organic framework (MOF) nanoplatform, termed a127/mito@ZIF@Ma is developed, which is sophistically designed for synergistic delivery of macrophage-derived mitochondria and anti-inflammatory miRNA-127 antagonist to resume pulmonary macrophages homeostasis and alleviate lung inflammation and injury. Notably, macrophage membrane encapsulation conferred the biomimetic MOF with enhanced transport efficacy both in vitro and in vivo. Therefore, the administration of the nanoparticles accordingly conferred a profound protection of mice against lung inflammation and injury induced by either bacterial or viral infection with unnoticeable tissue toxicity. The study thus devises a novel MOF-based nanosystem that integrates mitochondria transplantation and miRNA therapeutics, which may open a new avenue for treating ALI and relevant critical diseases.

Exosomes in Ovarian Cancer: Towards Precision Oncology

Background: Identification of targetable biomarkers to improve early disease detection and overall patient outcomes is becoming an urgent need in clinical oncology. Ovarian cancer (OC) has one of the highest mortality rates among gynecological cancers. It is asymptomatic and almost always diagnosed at an advanced stage (III or IV), leading to a 5-year survival rate of approximately 35%. Methods: Current therapeutic approaches for OC are very limited and mainly consist of cytoreductive surgery and cisplatin plus taxane-based chemotherapy. No gender and tumor specific biomarkers are known. Exosomes, lipid bilayer vesicles of endocytic origin secreted by most cell types, represent sources of information for their involvement in the onset and progression of many diseases. Hence, research on exosome contents as tools and targets in precise oncology therapy provides knowledge essential to improving diagnosis and prognosis of the disease. Results: This review attempts to give an overview of how exosomes are implicated in ovarian carcinoma pathogenesis to trigger further cancer exosome-based investigations aimed at developing ovarian cancer fine-tuning diagnostic methodologies. Conclusions: It is essential to investigate exosome-based cancer drugs to advance understanding, improve treatment plans, create personalized strategies, ensure safety, and speed up clinical translation to increase patients' overall survival and quality of life. Papers published in PubMed and Web of Science databases in the last five years (2020-2024) were used as a bibliographic source.

The role of natural products targeting macrophage polarization in sepsis-induced lung injury

Sepsis-induced acute lung injury (SALI) is characterized by a dysregulated inflammatory and immune response. As a key component of the innate immune system, macrophages play a vital role in SALI, in which a macrophage phenotype imbalance caused by an increase in M1 macrophages or a decrease in M2 macrophages is common. Despite significant advances in SALI research, effective drug therapies are still lacking. Therefore, the development of new treatments for SALI is urgently needed. An increasing number of studies suggest that natural products (NPs) can alleviate SALI by modulating macrophage polarization through various targets and pathways. This review examines the regulatory mechanisms of macrophage polarization and their involvement in the progression of SALI. It highlights how NPs mitigate macrophage imbalances to alleviate SALI, focusing on key signaling pathways such as PI3K/AKT, TLR4/NF-κB, JAK/STAT, IRF, HIF, NRF2, HMGB1, TREM2, PKM2, and exosome-mediated signaling. NPs influencing macrophage polarization are classified into five groups: terpenoids, polyphenols, alkaloids, flavonoids, and others. This work provides valuable insights into the therapeutic potential of NPs in targeting macrophage polarization to treat SALI.

Extracellular vesicles derived from bone marrow mesenchymal stem cells ameliorate chronic liver damage via microRNA-136-5p

Chronic liver damage (CLD) encompasses a spectrum of conditions and poses a significant global health challenge, affecting millions of individuals. Currently, there is a deficiency of clinically validated therapeutics with minimal side effects. Emerging evidence underscores the significant potential of extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSC-EVs) as a promising therapeutic method for CLD. This study aimed to evaluate the influence of BMSC-EVs containing microRNA-136-5p (BMSC-EVs-miR-136-5p) on macrophage polarization during chronic liver injury and elucidate the mechanisms associated with the GNAS/PI3K/ERK/STAT3 axis. Surface markers of BMSCs were detected via Immunofluorescent Staining. Subsequently, EVs were harvested from the BMSC culture medium. In vivo fluorescence imaging was employed to locate the BMSC-EVs. Additionally, fluorescence microscopy was used to visualize the uptake of DIR-labeled BMSC-EVs by RAW264.7 cells. Various methods were employed to assess the impact of BMSC-EVs on the expression levels of inflammatory factors (IL-1β, IL-6, IL-10, and TNF-α), M1/M2 macrophage markers (iNOS and Arg-1), and members of inflammation-related signaling pathways (GNAS, PI3K, ERK, and STAT3) in RAW264.7 cells co-cultured with BMSC-EVs. Loss-of-function approaches targeting miR-136-5p in RAW264.7 cells were subsequently utilized to validate the role of BMSC-EVs-miR-136-5p. The Luciferase Reporter Assay indicates that GNAS was identified to be a target of miR-136-5p, and miR-136-5p demonstrating increased within BMSC-EVs compared to Raw264.7-EVs. BMSC-EVs-miR-136-5p mitigated CCl4-induced liver inflammation and improved liver function by Suppressing the GNAS/STAT3 Signaling. Notably, miR-136-5p suppressed lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. BMSC-EVs-miR-136-5p alleviates CLD by activating M2 polarization through the GNAS-mediated PI3K/ERK/STAT3 axis. Accordingly, the members of this axis may serve as therapeutic targets.

Exosomal miRNAs involvement in pathogenesis, diagnosis, and treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is the most common chronic autoimmune arthropathy worldwide. The initiation, and progression of RA involves multiple cellular and molecular pathways, and biological interactions. Micro RNAs (miRNAs) are characterized as a class of small non-coding RNAs that influence gene expression at the post-transcriptional level. Exosomes are biological nano-vesicles that are secreted by different types of cells. They facilitate communication and signalling between cells by transferring a variety of biological substances, such as proteins, lipids, and nucleic acids like mRNA and miRNA. Exosomal miRNAs were shown to be involved in normal and pathological conditions. In RA, deregulated exosomal miRNA expression was observed to be involved in the intercellular communication between synovial cells, and inflammatory or regulatory immune cells. Furthermore, circulating exosomal miRNAs were introduced as available diagnostic and prognostic biomarkers for RA pathology. The current review categorized and summarized dysregulated pathologically involved and circulating exosomal miRNAs in the context of RA. It highlighted present situation and future perspective of using exosomal miRNAs as biomarkers and a specific gene therapy approach for RA treatment.

Mechanisms underlying the involvement of peritoneal macrophages in the pathogenesis and novel therapeutic strategies for dialysis-induced peritoneal fibrosis

Long-term exposure of the peritoneum to peritoneal dialysate results in pathophysiological changes in the anatomical organization of the peritoneum and progressive development of peritoneal fibrosis. This leads to a decline in peritoneal function and ultrafiltration failure, ultimately necessitating the discontinuation of peritoneal dialysis, severely limiting the potential for long-term maintenance. Additionally, encapsulating peritoneal sclerosis, a serious consequence of peritoneal fibrosis, resulting in patients discontinuing PD and significant mortality. The causes and mechanisms underlying peritoneal fibrosis in patients undergoing peritoneal dialysis remain unknown, with no definitive treatment available. However, abnormal activation of the immune system appears to be involved in altering the structure of the peritoneum and promoting fibrotic changes. Macrophage infiltration and polarization are key contributors to pathological injury within the peritoneum, showing a strong correlation with the epithelial-to-mesenchymal transition of mesothelial cells and driving the process of fibrosis. This article discusses the role and mechanisms underlying macrophage activation-induced peritoneal fibrosis resulting from PD by analyzing relevant literature from the past decade and provides an overview of recent therapeutic approaches targeting macrophages to treat this condition.

Fasciola hepatica Excretory-Secretory Products (Fh-ES) Either Do Not Affect miRNA Expression Profile in THP-1 Macrophages or the Changes Are Undetectable by a Microarray Technique

Fasciola hepatica is a liver fluke that resides in the bile ducts of various mammals. The parasitosis leads to economic losses in animal production estimated at USD 3.2 billion annually. It is also considered a zoonosis of great significance and a problem for public health affecting 2.4 million people worldwide. Nevertheless, besides the negative aspects of infestation, the antigens released by the fluke, F. hepatica Excretory-Secretory Products (Fh-ES) contain several immunomodulatory molecules that may be beneficial during the course of type I diabetes, multiple sclerosis, ulcerative colitis, or septic shock. This phenomenon is based on the natural abilities of adult F. hepatica to suppress proinflammatory responses. To underline the molecular basis of these mechanisms and determine the role of microRNA (miRNA) in the process, lipopolysaccharide (LPS)-activated THP-1 macrophages were stimulated with Fh-ES, followed by miRNA microarray analyses. Surprisingly, no results indicating changes in the miRNA expression profile were noted (p < 0.05). We discuss potential reasons for these results, which may be due to insufficient sensitivity to detect slight changes in miRNA expression or the possibility that these changes are not regulated by miRNA. Despite the negative data, this work may contribute to the future planning of experiments by other researchers.

Advances in Nanomedicine and Biomaterials for Endometrial Regeneration: A Comprehensive Review

The endometrium is an extremely important component of the uterus and is crucial for individual health and human reproduction. However, traditional methods still struggle to ideally repair the structure and function of damaged endometrium and restore fertility. Therefore, seeking and developing innovative technologies and materials has the potential to repair and regenerate damaged or diseased endometrium. The emergence and functionalization of various nanomedicine and biomaterials, as well as the proposal and development of regenerative medicine and tissue engineering techniques, have brought great hope for solving these problems. In this review, we will summarize various nanomedicine, biomaterials, and innovative technologies that contribute to endometrial regeneration, including nanoscale exosomes, nanomaterials, stem cell-based materials, naturally sourced biomaterials, chemically synthesized biomaterials, approaches and methods for functionalizing biomaterials, as well as the application of revolutionary new technologies such as organoids, organ-on-chips, artificial intelligence, etc. The diverse design and modification of new biomaterials endow them with new functionalities, such as microstructure or nanostructure, mechanical properties, biological functions, and cellular microenvironment regulation. It will provide new options for the regeneration of endometrium, bring new hope for the reconstruction and recovery of patients' reproductive abilities.

Role of M1/M2 macrophages in pain modulation

Pain is a signal of inflammation that can have both protective and pathogenic effects. Macrophages, significant components of the immune system, play crucial roles in the occurrence and development of pain, particularly in neuroimmune communication. Macrophages exhibit plasticity and heterogeneity, adopting either pro-inflammatory M1 or anti-inflammatory M2 phenotypes depending on their functional orientation. Recent research highlights the contribution of macrophages to pain dynamics by undergoing changes in their functional polarity, leading to macrophage activation, tissue infiltration, and cytokine secretion. M1 macrophages release pro-inflammatory mediators that are not only essential in defending against infections, but also contributing to tissue damage and the elicitation of pain. However, this process can be counteracted by M2 macrophages, facilitating pain relief through producing anti-inflammatory cytokines and opioid peptides or enhancing efferocytosis. M1 and M2 macrophages play important roles in both the initiation and mitigation of pain.

Innate immune cells: Key players of orchestra in modulating tumor microenvironment (TME)

The tumor microenvironment (TME) with vital role in cancer progression is composed of various cells such as endothelial cells, immune cells, and mesenchymal stem cells. In particular, innate immune cells such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, innate lymphoid cells, γδT lymphocytes, and natural killer cells can either promote or suppress tumor progression when present in the TME. An increase in research on the cross-talk between the TME and innate immune cells will lead to new approaches for anti-tumoral therapeutic interventions. This review primarily focuses on the biology of innate immune cells and their main functions in the TME. In addition, it summarizes several innate immune-based immunotherapies that are currently tested in clinical trials.

Role of microRNAs in Immune Regulation with Translational and Clinical Applications

MicroRNAs (miRNAs) are 19-23 nucleotide long, evolutionarily conserved noncoding RNA molecules that regulate gene expression at the post-transcriptional level. In this review, involvement of miRNAs is summarized in the differentiation and function of immune cells, in anti-infective immune responses, immunodeficiencies and autoimmune diseases. Roles of miRNAs in anticancer immunity and in the transplantation of solid organs and hematopoietic stem cells are also discussed. Major focus is put on the translational clinical applications of miRNAs, including the establishment of noninvasive biomarkers for differential diagnosis and prediction of prognosis. Patient selection and response prediction to biological therapy is one of the most promising fields of application. Replacement or inhibition of miRNAs has enormous therapeutic potential, with constantly expanding possibilities. Although important challenges still await solutions, evaluation of miRNA fingerprints may contribute to an increasingly personalized management of immune dysregulation with a remarkable reduction in toxicity and treatment side effects. More detailed knowledge of the molecular effects of physical exercise and nutrition on the immune system may facilitate self-tailored lifestyle recommendations and advances in prevention.