MicroRNA-139-5p mediates BMSCs impairment in diabetes by targeting HOXA9/c-Fos

Recent research advances of c-fos in regulating cell senescence

c-fos is an immediate early gene (IEG) that forms a heterodimeric activator protein-1 (AP-1) complex with c-Jun. Following stimulation by a variety of factors, it changes the expression of genes and participates in cellular growth, proliferation, differentiation, and apoptosis. Previous studies have reported that c-fos is linked to cellular senescence and is involved in aging-related signaling pathways or damage repair processes. However, there are limited studies related to this topic. This review summarizes the findings of the connection between c-fos and cellular senescence, including the regulatory role of c-fos in the senescence of stem cells and various kinds of somatic cells. In addition, we discussed the involvement of c-fos in the cellular senescence process and related signaling pathways, as well as the importance of regulating DNA damage repair. The current studies have demonstrated that c-fos has important roles in inhibiting stem cell senescence. They can pave the way for a more thorough examination of the aging process and the regeneration of stem cells and provide new therapeutic strategies for aging-related diseases.

miRNAs and their multifaceted role in cutaneous wound healing

The dynamic, complex process of cutaneous wound healing is required to restore skin integrity following an injury. This intricate process consists of four sequential and overlapping phases: hemostasis, inflammation, proliferation, and remodeling. Hemostasis immediately begins to function in response to vascular injury, forming a clot that stops the bleeding. To fight infection and remove debris, immune cells are enlisted during the inflammatory phase. Angiogenesis, re-epithelialization, and the creation of new tissue are all components of proliferation, whereas tissue maturation and scarring are the outcomes of remodeling. Chronic wounds, like those found in diabetic ulcers, frequently stay in a state of chronic inflammation because they are unable to go through these stages in a coordinated manner. The important regulatory roles that microRNAs (miRNAs) play in both normal and pathological wound healing have been highlighted by recent investigations. The miRNAs, small non-coding RNAs, modulate gene expression post-transcriptionally, profoundly impacting cellular functions. During the inflammatory phase, miRNAs control pro- and anti-inflammatory cytokines, as well as the activity of immune cells such as neutrophils and macrophages. Additionally, miRNAs are essential components of signaling networks related to inflammation, such as the toll-like receptor (TLR), nuclear factor kappa B (NF-kB), and Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathways. Some miRNAs have been discovered to either increase or alleviate inflammatory reactions, indicating their potential as therapeutic targets. Other miRNAs aid in angiogenesis by promoting the development of new blood vessels, which are essential for providing oxygen and nutrients to the healing tissue. They also affect keratinocyte migration and proliferation during the re-epithelialization phase, which involves growing new epithelial cells over the lesion. Another function of miRNAs is that they control the deposition of extracellular matrix (ECM) and the creation of scars during the remodeling phase. The abnormal expression of miRNAs in chronic wounds has led to the exploration of miRNA-based treatments. With a focus on resistant instances such as diabetic wounds, these therapeutic techniques seek to improve wound healing results by correcting the dysregulated miRNA expression.

Inhibition of microRNA-139-5p Improves Fibroblasts Viability and Enhances Wound Repair in Diabetic Rats Through AP-1 (c-Fos/c-Jun)

Introductions

Diabetic foot ulcers (DFU) are notoriously difficult to heal, however, its underlying molecular mechanisms are unknown. MicroRNA-139-5p participates in various biological processes, including cancer and vascular endothelial injury, while its role in diabetic wound healing has not been reported.

Methods

Sprague-Dawley (SD) rats were intraperitoneally injected with streptozotocin and a 1.0 cm full-layer dorsal skin wound was made to establish a diabetic wound model. On days 1, 4, 7, and 10 after the wound was made, a solution containing microRNA-139-5p antagomir or control was injected along the dorsal edge of the wound. Wound healing was analyzed using Image J, histological analysis and molecular analysis. Skin tissues from 4 diabetic and 4 matched non-diabetic ulcer patients were obtained to detect microRNA-139-5p expression. In vitro, human skin fibroblasts were transfected with microRNA-139-5p inhibitors/mimics, the function of the fibroblasts was evaluated by CCK-8 assay and scratch assay, and AP-1 (c-Fos/c-Jun) was detected.

Results

Obviously elevated microRNA-139-5p expression was detected in the wound tissue of the rats with diabetes and patients with DFUs, and the microRNA-139-5p antagonist-treated diabetic wounds had faster healing rates. The pace of diabetic wound re-epithelialization and angiogenesis was accelerated, and the expression of AP-1 family members (c-Fos/c-Jun), and VEGF, PDGF was upregulated in the wound tissue of diabetic rats treated with topical microRNA-139-5p antagomir. In vitro, the expression of microRNA-139-5p was up-regulated in human skin fibroblasts induced by high glucose treatment, while the function of the cell proliferation and migration was promoted and the level of AP-1 (c-Fos/c-Jun) was increased after transfected with the microRNA-139-5p inhibitor, and vice versa. Our study further verified that microRNA-139-5p regulated the migration of human skin fibroblasts by modulating c-Fos.

Conclusion

Inhibiting microRNA-139-5p improves fibroblasts viability and promotes diabetic wound healing, suggesting that this may be a therapeutic strategy for diabetic foot ulcer.

Role of microRNAs in diabetic foot ulcers: Mechanisms and possible interventions

Diabetic foot ulcer (DFU) is a common and serious complication among diabetic patients, and its incidence and difficulty in treatment have placed large burdens on patient health and quality of life. Diabetic foot tissue typically exhibits chronic wounds, ulcers, or necrosis that are difficult to heal, are prone to infection, and, in severe cases, may even lead to amputation. Recent studies have shown that microRNAs (miRNAs) play key roles in the development and healing of DFUs. miRNAs are a class of short noncoding RNA molecules that regulate gene expression to affect cellular functions and physiological processes. miRNAs may be involved in the development of DFUs by regulating cell growth, proliferation, differentiation and apoptosis. miRNAs can also participate in the healing and recovery of DFUs by regulating key steps, such as inflammation, angiogenesis, cell migration and proliferation, tissue repair and matrix remodeling. Therefore, altering the pathological processes of diabetic foot by modulating the expression of miRNAs could improve the recovery and treatment outcomes of patients. This review provides new insights and perspectives for the treatment of DFUs by summarizing the roles of miRNAs in the development and healing of DFUs and the mechanisms.

Role of exosome-derived miRNAs in diabetic wound angiogenesis

Chronic wounds with high disability are among the most common and serious complications of diabetes. Angiogenesis dysfunction impair wound healing in patients with diabetes. Compared with traditional therapies that can only provide symptomatic treatment, stem cells-owing to their powerful paracrine properties, can alleviate the pathogenesis of chronic diabetic wounds and even cure them. Exosome-derived microRNAs (miRNAs), important components of stem cell paracrine signaling, have been reported for therapeutic use in various disease models, including diabetic wounds. Exosome-derived miRNAs have been widely reported to be involved in regulating vascular function and have promising applications in the repair and regeneration of skin wounds. Therefore, this article aims to review the current status of the pathophysiology of exosome-derived miRNAs in the diabetes-induced impairment of wound healing, along with current knowledge of the underlying mechanisms, emphasizing the regulatory mechanism of angiogenesis, we hope to document the emerging theoretical basis for improving wound repair by restoring angiogenesis in diabetes.

Unveiling FOS as a Potential Diagnostic Biomarker and Emetine as a Prospective Therapeutic Agent for Diabetic Nephropathy

Background

Diabetic nephropathy (DN) is one of the primary causes of end-stage renal disease, yet effective therapeutic targets remain elusive. This study aims to identify novel diagnostic biomarkers and potential therapeutic candidates for DN.

Methods

Differentially expressed genes (DEGs) in GSE96804 and GSE142025 were identified and functional enrichment analysis was performed. Diagnostic biomarkers were selected using machine learning algorithms and evaluated by Receiver Operating Characteristic analysis. c-Fos expression was validated in an established DN mouse model. Immune infiltration levels were assessed with Single-Sample Gene Set Enrichment Analysis. Co-expression analysis revealed regulatory relationships involving FOS. cMAP predicted potential therapeutic candidates. Transcriptome sequencing and experiments in RAW264.7 cells was performed to investigate molecular mechanisms of emetine.

Results

In both datasets, we identified 44 upregulated and 74 downregulated DEGs involved in focal adhesion, ECM-receptor interaction, and the PI3K-Akt signaling pathway. FOS emerged as a robust diagnostic marker with decreased expression in DN patients and DN mouse. Co-expression analysis revealed potential regulatory mechanisms of FOS, implicating the MAPK signaling pathway, regulation of cell proliferation and apoptotic signaling pathways. Immune dysregulation was observed in DN patients. Notably, emetine was identified as a potential therapeutic candidate. Transcriptome sequencing and experimental validation demonstrated emetine suppressed M1 macrophage polarization by inhibiting the activation of NF-κB signaling pathway, as well as reducing the expression of Il-18 and Ccl5.

Conclusion

In conclusion, our study identified FOS as a promising diagnostic biomarker and emetine as a potential therapeutic candidate for DN. These findings enhance our understanding of DN pathogenesis and present novel prospects for therapeutic strategies.

mTOR Signaling Pathway in Bone Diseases Associated with Hyperglycemia

The interplay between bone and glucose metabolism has highlighted hyperglycemia as a potential risk factor for bone diseases. With the increasing prevalence of diabetes mellitus worldwide and its subsequent socioeconomic burden, there is a pressing need to develop a better understanding of the molecular mechanisms involved in hyperglycemia-mediated bone metabolism. The mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase that senses extracellular and intracellular signals to regulate numerous biological processes, including cell growth, proliferation, and differentiation. As mounting evidence suggests the involvement of mTOR in diabetic bone disease, we provide a comprehensive review of its effects on bone diseases associated with hyperglycemia. This review summarizes key findings from basic and clinical studies regarding mTOR's roles in regulating bone formation, bone resorption, inflammatory responses, and bone vascularity in hyperglycemia. It also provides valuable insights into future research directions aimed at developing mTOR-targeted therapies for combating diabetic bone diseases.

Effects of microRNAs on angiogenesis in diabetic wounds

Diabetes mellitus is a morbid condition affecting a growing number of the world population, and approximately one third of diabetic patients are afflicted with diabetic foot ulcers (DFU), which are chronic non-healing wounds that frequently progress to require amputation. The treatments currently used for DFU focus on reducing pressure on the wound, staving off infection, and maintaining a moist environment, but the impaired wound healing that occurs in diabetes is a constant obstacle that must be faced. Aberrant angiogenesis is a major contributor to poor wound healing in diabetes and surgical intervention is often necessary to establish peripheral blood flow necessary for healing wounds. Over recent years, microRNAs (miRNAs) have been implicated in the dysregulation of angiogenesis in multiple pathologies including diabetes. This review explores the pathways of angiogenesis that become dysregulated in diabetes, focusing on miRNAs that have been identified and the mechanisms by which they affect angiogenesis.