Insulin promotes macrophage phenotype transition through PI3K/Akt and PPAR-γ signaling during diabetic wound healing

A novel antioxidant and anti-inflammatory carboxymethylcellulose/chitosan hydrogel loaded with cannabidiol promotes the healing of radiation-combined wound skin injury in the 60Co γ-irradiated mice

BACKGROUND

Combined radiation and wound skin injury (RW) are frequently observed in patients undergoing tumor surgery plus radiotherapy, and but specific treatment is lacking. Chitosan (CS) and carboxymethyl cellulose (CMC) are commonly used to prepare hydrogel with good biocompatibility and low toxicity. Cannabidiol (CBD) has presented anti-inflammatory, antioxidant, and neuroprotective properties.

METHODS

CMC, CS, and CBD were used and designed for three types of hydrogels (CMC/CS2/CBD, CMC/CS3/CBD, CMC/CS4/CBD) with different ratios of CMC and CS based on previous report and our preliminary experiments. The CMC/CS/CBD hydrogel was synthesized using electrostatic interaction without chemical crosslinking, characterized via fourier transform infrared (FT-IR), and tested for mechanical properties, swelling behavior, biocompatibility, antioxidant activity, cytotoxicity, and hemocompatibility. 60Co γ irradiation (5 Gy, 0.62 Gy/min) combined with 1 cm circular trauma was applied to establish RW mice model. Topical applications of CMC/CS3, CMC/CS2/CBD, CMC/CS3/CBD were used to treat RW injury once a day for 10 consecutive days. The mice were euthanized 7, 14, 21 days after radiation, and samples were collected.

RESULTS

FT-IR confirmed the successful formation of a polyelectrolyte network. The CMC/CS3/CBD hydrogel exhibited optimal mechanical strength, rapid gelation, high swelling capacity, and excellent biocompatibility. Both CMC/CS2/CBD and CMC/CS3/CBD hydrogels effectively improved RW injury 7, 14, 21 days after radiation. Reduced inflammation and increased collagen production were observed the two groups. The significant increased expression of interleukin (IL)-1β, IL-22, IL-17A, IL-6, tumor necrosis factor-α, granulocyte-macrophage colony-stimulating factor, CC motif chemokine ligand (CCL)2, CCL3, CCL4, CCL5, CCL11 in the RW group was greatly inhibited after treatment with CMC/CS3/CBD hydrogel. Transcriptome analysis revealed the hydrogel's impact on lipid metabolism and epithelial differentiation pathways.

CONCLUSIONS

By integrating CBD into a CMC/CS-based hydrogel without using toxic crosslinkers, this study provides a novel, biomaterial-based, biocompatible approach for RW injury. These findings pave the way for future clinical application of CMC/CS3/CBD hydrogel in RW injury.

Endogenous sulfur dioxide deficiency impairs bone regeneration through abolishing S-sulfenylating p38 at cysteine 211

Bone defects result in substantial medical expenses and a diminished quality of life for patients. Macrophage polarization is crucial in the bone regeneration process mediated by bone marrow-derived mesenchymal stem cells (BMSCs). macrophage-derived sulfur dioxide (SO2), the fourth endogenous gas signaling molecule, following hydrogen sulfide (H2S), has been shown to regulate macrophage chemotaxis and inflammatory responses. Nevertheless, the specific regulatory effects and mechanisms of macrophage-derived SO2 on bone regeneration are not yet fully understood. This study reveals for the first time that the absence of macrophage-derived SO2 promotes M1 macrophage polarization, whereas the administration of exogenous SO2 donors inhibits M1 polarization. The deficiency of macrophage-derived SO2 results in impaired osteogenic differentiation of BMSCs, whereas the administration of SO2 donors enhances this differentiation process. Further investigations have elucidated that p38α MAPK (p38) is crucial in mediating SO2's effects on M1 macrophage polarization and BMSCs osteogenic differentiation. Mechanistically, SO2 induces S-sulfenylation of p38 in macrophages, an effect that can be reversed by the thiol reductant dithiothreitol. Additionally, the C211S mutation in p38 abrogates the SO2-induced S-sulfenylation of p38, thereby preventing the inhibition of p38 activation and subsequently disrupting the regulation of M1 macrophage polarization and BMSCs osteogenic differentiation. In a model of mouse calvarial bone defects, we consistently observed that inhibiting SO2 production using the SO2-generating enzyme inhibitor HDX impaired bone regeneration capacity in mice, whereas the administration of an SO2 donor enhanced this capacity. In summary, macrophage-derived SO2 S-sulfenylates p38 at cysteine 211, thereby suppressing p38 activation, which inhibits M1 polarization and subsequently maintains the osteogenic differentiation of BMSCs. This study is the first to elucidate the role and mechanism of SO2 in sustaining osteogenesis, offering a novel strategy for addressing bone defect-related disorders.

The therapeutic potential of Rosiglitazone in modulating scar formation through PPAR-γ pathway

The prevention and treatment of scars has always posed a challenge in the medical field. Researchers have reached the consensus that safe, effective and affordable treatments are needed. Here, by conducting non-targeted metabolomics and RNA sequencing experiments, we revealed that a significant number of metabolites and genes related to glucose and lipid metabolism underwent changes during scar formation, with peroxisome proliferator-activated receptor-γ (PPAR-γ) exerting a profound influence. Considering that rosiglitazone is a selective orally active PPAR-γ receptor agonist, scar models were induced in rats, and rosiglitazone was administered at different dosages. We characterized rosiglitazone as a crucial mediator in a rat scar model in vivo and in vitro in two models of transforming growth factor β1(TGF-β1) stimulated fibroblasts (NIH 3T3 and 3T3 L1). Functionally, activation of PPAR-γ with rosiglitazone effectively impedes fibrosis and mitigates scar formation. Rosiglitazone also inhibits some inflammatory factors, and downregulates triglyceride, lactic acid, glycogen and lactic dehydrogenase levels in rat scars. Conversely, rosiglitazone increases adenosine triphosphate (ATP) production and increases free fatty acid levels and the activity of acetyl-CoA carboxylase, fatty acid synthetase, succinate dehydrogenase. Collectively, these findings shed light on the underlying mechanisms and suggest that the use of rosiglitazone could be a promising therapeutic approach to alleviate fibrosis and reduce scar formation.

Insulin/PHMB-grafted sodium alginate hydrogels improve infected wound healing by antibacterial-prompted macrophage inflammatory regulation

BACKGROUND

Non-healing chronic wounds with high susceptibility to infection represent a critical challenge in modern healthcare. While growth factors play a pivotal role in regulating chronic wound repair, their therapeutic efficacy is compromised in infected microenvironments. Current wound dressings inadequately address the dual demands of sustained bioactive molecule delivery and robust antimicrobial activity.

RESULTS

In this study, we developed a sodium alginate hydrogel (termed P-SA/Ins), which incorporated polyhexamethylene biguanide (PHMB) grafting and long-acting glargine insulin loading. P-SA/Ins exhibited the favorable physicochemical performance, biocompatibility and antibacterial efficacy against both Gram-negative and Gram-positive pathogens through inhibition of bacterial proliferation and biofilm formation. Glargine insulin was applied to prolonged insulin delivery. P-SA/Ins treatment attenuated S. aureus induced pro-inflammatory cytokine cascades in macrophages. The evaluation in vivo using a rat model with S. aureus infected wound demonstrated that P-SA/Ins significantly enhanced wound healing and optimized skin barrier through antimicrobial-mediated modulation of macrophage polarization and subsequent inflammatory cytokine profiling.

CONCLUSIONS

Our findings demonstrate that P-SA/Ins promotes wound healing and restores epidermal barrier integrity, indicating its potential as a therapeutic dressing for chronic wound healing, particularly in cases with infection risk.

Resveratrol Promotes Wound Healing by Enhancing Angiogenesis via Inhibition of Ferroptosis

Diabetic wound healing critically depends on functional endothelial cells for angiogenesis, yet the hyperglycemic microenvironment induces endothelial dysfunction through oxidative stress, inflammation, and senescence. Although ferroptosis has been recognized as a critical pathological factor contributing to impaired diabetic wound healing, the therapeutic potential of resveratrol (Res), a natural polyphenol with well-documented antioxidant and anti-ferroptotic properties, remains underexplored in this context. This study aimed to investigate the protective effects of Res on endothelial cells and elucidate its underlying mechanisms in diabetic wound healing. In vitro experiments systematically evaluated Res's impact on cellular inflammatory responses, senescence levels, and angiogenic capacity. Subsequent in vivo studies assessed Res's therapeutic potential by monitoring diabetic wound healing progression and analyzing associated histological changes. To clarify the mechanisms underlying Res's promotion of diabetic wound healing, we conducted comprehensive analyses measuring intracellular reactive oxygen species, lipid peroxidation levels, mitochondrial membrane potential and morphology, ferroptosis-related marker expression, and upstream signaling pathway regulation. Res significantly reduced HG-induced inflammatory responses and cellular senescence in human umbilical vein endothelial cells while enhancing their angiogenic potential in vitro. In vivo results showed that Res not only markedly accelerated diabetic wound healing but also demonstrated multiple beneficial effects, including effective suppression of cellular senescence, decreased ferroptosis levels, and significantly promoted angiogenesis. Mechanistic investigations confirmed that Res achieves these effects by inhibiting ferroptosis through activation of the PI3K-AKT-Nrf2 signaling axis. Our results demonstrate that Res protects endothelial cells from HG-induced ferroptosis by activating PI3K-AKT-Nrf2 signaling, thereby promoting angiogenesis and diabetic wound healing. These findings highlight Res as a promising therapeutic candidate for impaired diabetic wound repair and justify further clinical investigation.

Machine learning-assisted analysis of serum metabolomics and network pharmacology reveals the effective compound from herbal formula against alcoholic liver injury

BACKGROUND

The popularity of herbal formulas is increasing worldwide. Nevertheless, the effective compound is challenging to identify due to its intricate composition and multiple targets.

METHODS

An integration machine learning-assisted approach was established, whereby the particular action mechanism and direct target were obtained through the correlation of compounds, targets, and metabolites. The association between a compound and an action pathway was selected from the shortest path of the "compound-target-pathway-disease" network, which was analyzed using the Floyd-Warshall algorithm. Subsequently, an investigation was conducted into the relationship between metabolites and action pathways, as well as targets, through the analysis of serum metabolomic profiling and the selection of metabolite biomarkers by random forest. In order to accurately identify the direct acting target as well as the most effective compound, the relationship between the compounds and their targets was investigated using a feature-based prediction model conducted by AdaBoost. The binding mode of the effective compound and the direct-acting target was verified by molecular docking, dynamics simulations, and western blotting. In this study, Baiji Wuweizi Granule (BWG) was employed to elucidate the effective compound against alcoholic liver injury (ALD).

RESULTS

BWG exerted an influence on the serum metabolomic, resulting in the identification of seven potential biomarkers. Furthermore, six effective compounds and the PI3K-AKT signalling pathway were identified through a co-analysis with the shortest path from compound to ALD in the "compound-target-pathway-disease" network. It was postulated that the effective compounds would bind with key targets from the PI3K-AKT signaling pathway, as indicated by the prediction model of compound-target interaction (R2 > 0.95). The dominant bonding type for the effective compounds and key targets was hydrogen bond. These results indicated that AKT1 was the notable target for BWG, and that 2,3,4,7-tetramethoxyphenanthrene was the marker compound for BWG against ALD. The present study provides evidence that the protective effect of BWG on ALD can be mediated by the PI3K-AKT signaling pathway.

CONCLUSIONS

Our findings demonstrate the value of a machine learning-assisted approach in identifying the key compound, target and pathway that underpin the efficacy of an herbal formula. This provides a foundation for future clinical and fundamental research.

Microenvironment-adaptive nanomedicine MXene promotes flap survival by inhibiting ROS cascade and endothelial pyroptosis

In the field of large-area trauma flap transplantation, preventing avascular necrosis remains a critical challenge. Key mechanisms for improving flap viability include angiogenesis promotion, oxidative stress inhibition, and cell death prevention. Recently, two-dimensional ultrathin Ti3C2TX (MXene) nanosheets have gained attention for their potential contributions to these processes, though MXene's physiological impact on flap survival had not been previously investigated. This study is the first to confirm MXene's biological effects on the ischaemic microenvironment post-skin flap transplantation. Findings indicated that MXene significantly decreased the necrotic area in ischaemic flaps (37.96% ± 2.00%), with reductions of 30.40% ± 1.86% at 1 mg/mL and 20.19% ± 2.11% at 2 mg/mL in a concentration-dependent manner. Mechanistically, MXene facilitated in situ angiogenesis, mitigated oxidative stress, suppressed pro-inflammatory pyroptosis, and activated the PI3K-Akt pathway, particularly influencing vascular endothelial cells. Comparative transcriptome analysis of skin tissues with and without MXene treatment provided additional evidence, highlighting mechanisms such as pro-inflammatory pyroptosis, ROS metabolic processes, endothelial cell proliferation regulation, and PI3K-Akt signaling pathway activation. Overall, MXene demonstrated biological activity, effectively promoting ischaemic flaps survival and presenting a novel strategy for addressing ischaemic necrosis in skin flaps.

Inhibition of bone morphogenetic protein 4 alleviates angiotensin II-induced abdominal aortic aneurysm by reducing inflammation and endothelial-mesenchymal transition

BACKGROUND AND AIMS

Abdominal aortic aneurysm (AAA) is one of the most common fatal macrovascular diseases worldwide which pathogenesis is still not well clarified. In this study, we systematically investigated the alternations of endothelial cell (ECs) functions and phenotypes by single-cell RNA sequencing in angiotensin (Ang) II-induced AAA mice models.

METHOD AND RESULTS

According to 10 × single-cell sequencing analysis, we revealed that ECs inflammation and endothelial-mesenchymal transition (EndoMT) were involved in the progress of Ang II-induced AAA. Three types of ECs, including Mature ECs (uninjured ECs), EndoMT ECs and Injury & inflammation ECs successively emerged during the progression of AAA. By using pseudotime-trajectory analysis, we speculated bone morphogenetic protein 4 (BMP4) as a candidate gene, participating in Ang II-induced AAA by regulating EndoMT and vascular inflammation. We found that inhibition of BMP4 ameliorated EndoMT and vascular inflammation in Ang II-induced AAA in vivo. In addition, we found that exogenous BMP4 directly promoted the phenotypic transition, inflammation, cell migration and invasion of mouse aortic endothelial cells via PI3K/AKT/mTOR pathways in vitro. Finally, Protein-protein interaction (PPI) analysis and co-immunoprecipitation (Co-IP) revealed that biglycan (BGN) directly combined with BMP4 and promoted the conversion of EndoMT.

CONCLUSION

Our findings firstly revealed a critical role of BMP4 in AAA progression, which promoted disease progression by inducing EndoMT and reprogramming ECs from anti-inflammatory to proinflammatory phenotype.

Extracellular Vesicle-Associated miR-ERIA Exerts the Antiangiogenic Effect of Macrophages in Diabetic Wound Healing

ARTICLE HIGHLIGHTS

An understanding of cell interactions is needed to identify therapeutic targets for diabetic cutaneous ulcers. We explored extracellular vesicles after treatment with advanced glycation end products (AGEs-EVs) derived from macrophages that can suppress diabetic cutaneous wound healing. We found that a novel miRNA enriched in AGEs-EVs (miR-ERIA) suppresses the migration and tube formation of vascular endothelial cells by targeting helicase with zinc finger 2. miR-ERIA offers a potential therapeutic target for diabetic cutaneous ulcers.

Research progress and strategy of FGF21 for skin wound healing

Fibroblast Growth Factor 21 (FGF21), a pivotal member of the fibroblast growth factor family, exhibits multifaceted biological functions, including the modulation of pro-inflammatory cytokines and metabolic regulation. Recent research has revealed that in impaired skin tissues, FGF21 and its receptors are upregulated and play a significant role in accelerating the wound healing process. However, the clinical application of FGF21 is severely limited by its short in vivo half-life: this factor is often degraded by enzymes before it can exert its therapeutic effects. To address this limitation, the transdermal drug delivery system (TDDS) has emerged as an innovative approach that enables sustained drug release, significantly prolonging the therapeutic duration. Leveraging genetic recombination technology, research teams have ingeniously fused FGF21 with cell-penetrating peptides (CPPs) to construct recombinant FGF21 complexes. These novel conjugates can efficiently penetrate the epidermal barrier and achieve sustained and stable pharmacological activity through TDDS. This review systematically analyzes the potential signaling pathways by which FGF21 accelerates skin wound repair, summarizes the latest advancements in TDDS technology, explores the therapeutic potential of FGF21, and evaluates the efficacy of CPP fusion tags. The manuscript not only proposes an innovative paradigm for the application of FGF21 in skin injury treatment but also provides new insights into its use in transdermal delivery, marking a significant step toward overcoming existing clinical therapeutic challenges. From a clinical medical perspective, this innovative delivery system holds promise for addressing the bioavailability issues of traditional FGF21 therapies, offering new strategies for the clinical treatment of metabolism-related diseases and wound healing. With further research, this technology holds vast potential for clinical applications in hard-to-heal wounds such as diabetic foot ulcers and burns.

Mitochondrial dynamics at the intersection of macrophage polarization and metabolism

Macrophages are vital sentinels in innate immunity, and their functions cannot be performed without internal metabolic reprogramming. Mitochondrial dynamics, especially mitochondrial fusion and fission, contributes to the maintenance of mitochondrial homeostasis. The link between mitochondrial dynamics and macrophages in the past has focused on the immune function of macrophages. We innovatively summarize and propose a link between mitochondrial dynamics and macrophage metabolism. Among them, fusion-related FAM73b, MTCH2, SLP-2 (Stomatin-like protein 2), and mtSIRT, and fission-related Fis1 and MTP18 may be the link between mitochondrial dynamics and macrophage metabolism association. Furthermore, post-translational modifications (PTMs) of mtSIRT play prominent roles in mitochondrial dynamics-macrophage metabolism connection, such as deacetylates and hypersuccinylation. MicroRNAs such as miR-150, miR-15b, and miR-125b are also possible entry points. The metabolic reprogramming of macrophages through the regulation of mitochondrial dynamics helps improve their adaptability and resistance to adverse environments and provides therapeutic possibilities for various diseases.

LncRNA A1BG-AS1 regulates the progress of diabetic foot ulcers via sponging miR-214-3p

Nerve aberrations and vascular lesions in the distal lower limbs are the etiological factors for diabetic foot ulcers (DFUs). This study aimed to understand the regulatory mechanism of angiogenesis in patients with DFU by examining lncRNA, as well as to explore effective targets for diagnosing and treating DFU. The serum levels of A1BG-AS1 and miR-214-3p and the predictive power of A1BG-AS1 for DFU were determined by quantitative PCR and ROC analysis. The correlation of A1BG-AS1 with clinical characteristics was examined using chi-square tests. The risk factors for DFU in patients with type 2 diabetes mellitus (T2DM) were identified using the logistic regression model. Furthermore, the binding sites of A1BG-AS1 and miR-214-3p were determined. Next, A1BG-AS1 interference plasmid and miR-214-3p inhibitor were co-transfected into high glucose-induced cells to investigate their effects on the expression of angiogenesis-related genes and cell proliferation. The A1BG-AS1 levels were upregulated, whereas the miR-214-3p levels were downregulated in patients with DFU. The upregulation of A1BG-AS1 was significantly associated with both blood glucose levels and ulcer grades. A1BG-AS1 served as a crucial biomarker for diagnosing DFU and evaluating the risk of DFU occurrence in patients with T2DM. Co-transfection experiments revealed that the inhibition of miR-214-3p effectively recovered the suppressive effects of A1BG-AS1 on angiogenesis-related gene expression, endothelial cell differentiation, and proliferation. The sponging effect of A1BG-AS1 on miR-214-3p impaired angiogenesis in patients with DFU. Thus, A1BG-AS1 is a potential therapeutic target for DFU.

Sequential Targeting Chondroitin Sulfate-Bilirubin Nanomedicine Attenuates Osteoarthritis via Reprogramming Lipid Metabolism in M1 Macrophages

The infiltration and excessive polarization of M1 macrophages contribute to the induction and persistence of low-grade inflammation in joint-related degenerative diseases such as osteoarthritis (OA). The lipid metabolism dysregulation promotes M1 macrophage polarization by coordinating the compensatory pathways of the inflammatory and oxidative stress responses. Here, a self-assembling, licofelone-loaded nanoparticle (termed LCF-CSBN), comprising chondroitin sulfate and bilirubin joined by an ethylenediamine linker, is developed to selectively reprogram lipid metabolism in macrophage activation. LCF-CSBN is internalized by M1 macrophages via CD44-mediated endocytosis and targets the Golgi apparatus accompanied with the reactive oxygen species-responsive release of licofelone (LCF, dual inhibitor of arachidonic acid metabolism). LCF-CSBN effectively promotes M1 to M2 macrophage transition by reprogramming the Golgi apparatus-related sphingolipid metabolism and arachidonic acid metabolism. Intra-articularly injected LCF-CSBN retains in the joint for up to 28 days and accumulates into M1 macrophages. Moreover, LCF-CSBN can effectively attenuate joint inflammation, oxidative stress, and cartilage degeneration in OA model rats. These findings indicate the promising potential of lipid-metabolism-reprogramming LCF-CSBN in the targeted therapy of OA.

Integrated analysis of ATAC-seq and RNA-seq reveals the chromatin accessibility and transcriptional landscape of immunoglobulin a nephropathy

BACKGROUNDS

The association between chromatin accessibility in CD4+ T cells and Immunoglobulin A nephropathy (IgAN) remains unclear.

METHODS

We performed the assay for transposase accessible chromatin with sequencing (ATAC-seq) and RNA sequencing (RNA-seq) on CD4+ T cells. ATAC-seq and RNA-seq were conducted to identify differentially accessible regions and differentially expressed genes (DEGs), respectively (P < 0.05, |log2 Fold Change| >1). QRT-PCR was utilized to validate target gene expression.

RESULTS

We identified 100,865 differentially accessible regions, of which 7225 exhibited higher accessibility in IgAN. Functional analysis revealed that these regions are enriched in T lymphocyte activation and immune pathways. ELF3, MEIS1, and NFYC were identified as key TFs associated with IgAN. QRT-PCR indicated a significant upregulation of hub genes including MEIS1 in IgAN.

CONCLUSION

We identified key TFs and genes by integrating ATAC-seq and RNA-seq, which provide novel therapeutic targets for IgAN and insights into its pathogenesis from an epigenetic perspective.

Boswellia Extract Promotes Healing and Resolving Inflammation in Oral Ulcers of Rat

BACKGROUND

Recurrent aphthous ulcers significantly impact patients' quality of life due to their painful and recurrent nature, necessitating more effective treatments. This study explores the therapeutic potential of Boswellia to treat recurrent aphthous ulcers by its anti-inflammatory and healing promotion effect in a rat oral ulcer model.

METHODS

Network pharmacology techniques were employed to elucidate Boswellia's active components and potential targets. Intersecting targets of Boswellia and oral ulcer-related genes were screened for protein-protein interaction network analysis and functional enrichment. An oral ulcer model in rats was used and rats were treated with Boswellia extract. The healing process was monitored by measuring the ulcer area and body weight changes. Histological analysis was performed, and the role of Boswellia in macrophage polarization was investigated through gene expression analysis and protein array tests. The underlying mechanism involving PPARγ activation was also explored.

RESULTS

Network pharmacology analysis revealed Boswellia's interaction with key genes and pathways associated with inflammation and lipid metabolism, such as MAPK3, PPARG, and PTGS2. Boswellia extract significantly accelerated oral ulcer healing and recovered weight loss in rats. Histological examinations revealed reduced tissue swelling and inflammatory cell infiltration in treated groups. Furthermore, Boswellia extract decreased infiltration of M1 macrophage presence while increasing M2 macrophage, indicating an inflammation-resolving effect. In vitro studies showed that Boswellia extract enhanced M2-related gene expression and decreased pro-inflammatory cytokines, which is PPARγ dependent.

CONCLUSION

Boswellia extract promotes oral ulcer healing and resolves inflammation, primarily through the modulation of macrophage polarization via PPARγ activation.

Peroxisome proliferator-activated receptor gamma: A promising therapeutic target for the treatment of chronic pain

Chronic pain represents an incapacitating medical condition that profoundly impacts the patients' quality of life. Managing chronic pain poses a significant challenge for healthcare professionals due to its multifaceted nature and the limited effectiveness of current treatment options. Therefore, novel therapeutic interventions are crucially required for the management of chronic pain. Peroxisome proliferator-activated receptor gamma (PPARγ), a nuclear receptor, exerts regulatory effects on physiological processes such as glucose and lipid metabolism. Emerging studies demonstrate that PPARγ is a critical regulator of the expression of various genes, including those of anti-inflammatory cytokines and antioxidant enzymes. Substantial evidence indicates decreased expression of PPARγ in the sciatic nerve, dorsal root ganglia, and spinal cord dorsal horn in animal models of chronic pain. Furthermore, natural or synthetic PPARγ agonists had inhibitory effects on nociceptive hypersensitivity in various animal models of chronic pain. This review summarizes and discusses preclinical evidence demonstrating the therapeutic potential of PPARγ agonists in chronic pain management. The available evidence indicates that PPARγ activation reduces chronic pain by inhibiting neuroinflammation and oxidative stress as well as modulation of opioidergic system. Overall, the use of PPARγ agonists is a promising therapeutic approach for treating chronic pain; however, further research regarding its detailed mechanisms is warranted.

The efferocytosis dilemma: how neutrophil extracellular traps and PI3K/Rac1 complicate diabetic wound healing

AIMS/HYPOTHESIS

The resolution of apoptotic cells (ACs) is crucial for wound healing and tissue remodeling and is often impaired by persistent inflammation. This study aimed to elucidate the impact of neutrophil extracellular traps (NETs) on diabetic wound healing by targeting the phosphoinositide 3-kinase/Ras-related C3 botulinum toxin substrate 1 (PI3K/Rac1) signaling pathway, which is pivotal for macrophage efferocytosis.

METHODS

A streptozotocin-induced diabetic mouse model was used to assess the impact of NETs on efferocytosis in vivo. The effects of NETs on macrophage efferocytosis and wound healing were evaluated using specific inhibitors and agonists targeting the PI3K/Rac1 pathway. In vitro, macrophages from diabetic wounds or cell lines (Raw264.7) were treated with NETs and a panel of pharmacological agents of the PI3K/Rac1 pathway to evaluate macrophage efferocytosis.

RESULTS

NETs were found to inhibit macrophage efferocytosis, resulting in delayed clearance of ACs that accumulate within the wounds. Inhibition of NET formation in diabetic mice rescued impaired efferocytosis, accompanied by reactivation of PI3K and Rac1 in macrophages. Moreover, pharmacological agents targeting the PI3K/Rac1 pathway restored NETs-induced impairment in efferocytosis, leading to rapid wound healing. Raw264.7 cells exhibited elevated activation levels of PI3K and Rac1 when co-cultured with ACs in vitro. Nevertheless, this signaling activation was inhibited when cultured in a NETs-conditioned medium, leading to attenuated efferocytosis.

CONCLUSIONS/INTERPRETATION

Targeting NETs and the PI3K/Rac1 pathway emerges as a potential therapeutic strategy to enhance healing in diabetic wounds by promoting macrophage efferocytosis.

Effect and Mechanism of Tricholoma matsutake Extract on UVA and UVB Radiation-Induced Skin Aging

Ultraviolet (UV) radiation often causes skin aging, inflammation, cancer and other related skin diseases. In this study, the main components of Tricholoma matsutake extract (TME) were identified using UPLC-Q-TOF-MS, and their anti-photoaging effects were assessed through UV-induced cell and animal models. The key components identified were D-mannitol (27.41%), DL-malic acid (14%), alginate (12.5%), isoleucine (4.82%), and phenylalanine (4.31%), all of which played roles in anti-aging and UV protection. TME (50-100 mg/ml) significantly alleviated UVA/UVB-induced erythema and wrinkles in mice. Pathological staining showed that TME suppressed UV-induced epidermal hyperplasia (p < 0.05), reduced collagen damage (p < 0.01), and decreased mast cell infiltration (p < 0.01), while down-regulating inflammatory markers such as IL-6, IL-1β, and TNF-α. TME also upregulated type I collagen (COL-1). Flow cytometry results demonstrated that high-dose TME inhibited UV-induced apoptosis and reduced reactive oxygen species (ROS) in HaCaT cells (p < 0.05). Immunofluorescence and scratch migration assays showed that TME promoted PPAR-α expression, reduced inflammation, and supported skin repair (p < 0.01). Transcriptomic and metabolomic analyses indicated that TME regulated inflammation-related signaling pathways, helping to prevent skin aging. TME is a promising natural product for skin care and treatment of oxidative stress and inflammation-related diseases.

Mechanistic insights of diabetic wound: Healing process, associated pathways and microRNA-based delivery systems

Wounds that represent one of the most critical complications can occur in individuals suffering from diabetes mellitus, and results in the need for hospitalisation and, in severe cases, require amputation. This condition is primarily characterized by infections, persistent inflammation, and delayed healing processes, which exacerbate the overall health of the patients. As per the standard mechanism, signalling pathways such as PI3K/AKT, HIF-1, TGF-β, Notch, Wnt/β-Cat, NF-κB, JAK/STAT, TLR, and Nrf2 play major roles in inflammatory, proliferative and remodelling phases of wound healing. However, dysregulation of the above pathways has been seen during the healing of diabetic wounds. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate the expression of various genes and signalling pathways which are associated with the process of wound healing. In the past few years, there has been a great deal of interest in the potential of miRNAs as biological agents in the management of a number of disorders. These miRNAs have been shown to modulate expression of genes involved in the healing process of wounds. There have been previous reviews pertaining to clinical trials examining miRNAs in several disorders, but only a few clinical studies have examined involvement of miRNAs in healing of wounds. Considering the therapeutic promise, there are several obstacles concerning their instabilities and inefficient delivery into the target cells. Therefore, this review is an attempt to discuss precise roles of signalling pathways and miRNAs in different phases of wound healing, and their aberrant regulation in diabetic wounds, particularly. It has also compiled a range of delivery mechanisms as well as an overview of the latest findings pertaining to miRNAs and associated delivery systems for improved healing of diabetic wounds.

Impact of natural compounds on peroxisome proliferator-activated receptor: Molecular effects and its importance as a novel therapeutic target for neurological disorders

Neurological disorders refer to the pathological changes of the nervous system involving multiple pathological mechanisms characterized by complex pathogenesis and poor prognosis. Peroxisome proliferator-activated receptor (PPAR) is a ligand-activated transcription factor that is a member of the nuclear receptor superfamily. PPAR has attracted considerable attention in the past decades as one of the potential targets for the treatment of neurological disorders. Several in vivo and in vitro studies have confirmed that PPARs play a neuroprotective role by regulating multiple pathological mechanisms. Several selective PPAR ligands, such as thiazolidinediones and fibrates, have been approved as pharmacological agonists. Nevertheless, PPAR agonists cause a variety of adverse effects. Some natural PPAR agonists, including wogonin, bergenin, jujuboside A, asperosaponin VI, monascin, and magnolol, have been introduced as safe agonists, as evidenced by clinical or preclinical experiments. This review summarizes the effects of phytochemicals on PPAR receptors in treating various neurological disorders. Further, it summarizes recent advances in phytochemicals as potential, safe, and promising PPAR agonists to provide insights into understanding the PPAR-dependent and independent cascades mediated by phytochemicals. The phytochemicals exhibited potential for treating neurological disorders by inhibiting neuroinflammation, exerting anti-oxidative stress and anti-apoptotic activities, promoting autophagy, preventing demyelination, and reducing brain edema and neurotoxicity. This review presents data that will help clarify the potential mechanisms by which phytochemicals act as pharmacological agonists of PPARs in the treatment of neurological disorders. It also provides insights into developing new drugs, highlighting phytochemicals as potential, safe, and promising PPAR agonists. Additionally, this review aims to enhance understanding of both PPAR-dependent and independent pathways mediated by phytochemicals.

Therapeutic Properties of M2 Macrophages in Chronic Wounds: An Innovative Area of Biomaterial-Assisted M2 Macrophage Targeted Therapy

Wound healing is a dynamic, multi-stage process essential for restoring skin integrity. Dysregulated wound healing is often linked to impaired macrophage function, particularly in individuals with chronic underlying conditions. Macrophages, as key regulators of wound healing, exhibit significant phenotypic diversity, ranging from the pro-healing M2 phenotype to the pro-inflammatory M1 phenotype. Imbalances in the M1/M2 ratio or hyperactivation of the M1 phenotype can delay the normal healing. Consequently, strategies aimed at suppressing the M1 phenotype or promoting the shift of local skin macrophages toward the M2 phenotype can potentially treat chronic non-healing wounds. This manuscript provides an overview of macrophages' role in normal and pathological wound-healing processes. It examines various therapeutic approaches targeting M2 macrophages, such as ex vivo-activated macrophage therapy, immunopharmacological strategies, and biomaterial-directed macrophage polarization. However, it also highlights that M2 macrophage therapies and immunopharmacological interventions may have drawbacks, including rapid phenotypic changes, adverse effects on other skin cells, biotoxicity, and concerns related to biocompatibility, stability, and drug degradation. Therefore, there is a need for more targeted macrophage-based therapies that ensure optimal biosafety, allowing for effective reprogramming of dysregulated macrophages and improved therapeutic outcomes. Recent advances in nano-biomaterials have demonstrated promising regenerative potential compared to traditional treatments. This review discusses the progress of biomaterial-assisted macrophage targeting in chronic wound repair and addresses the challenges faced in its clinical application. Additionally, it explores novel design concepts for combinational therapies, such as incorporating regenerative particles like exosomes into dressing materials or encapsulating them in microneedling systems to enhance wound healing rates.

Extracellular Vesicles-in-Hydrogel (EViH) targeting pathophysiology for tissue repair

Regenerative medicine endeavors to restore damaged tissues and organs utilizing biological approaches. Utilizing biomaterials to target and regulate the pathophysiological processes of injured tissues stands as a crucial method in propelling this field forward. The Extracellular Vesicles-in-Hydrogel (EViH) system amalgamates the advantages of extracellular vesicles (EVs) and hydrogels, rendering it a prominent biomaterial in regenerative medicine with substantial potential for clinical translation. This review elucidates the development and benefits of the EViH system in tissue regeneration, emphasizing the interaction and impact of EVs and hydrogels. Furthermore, it succinctly outlines the pathophysiological characteristics of various types of tissue injuries such as wounds, bone and cartilage injuries, cardiovascular diseases, nerve injuries, as well as liver and kidney injuries, underscoring how EViH systems target these processes to address related tissue damage. Lastly, it explores the challenges and prospects in further advancing EViH-based tissue regeneration, aiming to impart a comprehensive understanding of EViH. The objective is to furnish a thorough overview of EViH in enhancing regenerative medicine applications and to inspire researchers to devise innovative tissue engineering materials for regenerative medicine.

Effect of Application of Autologous Conditioned Serum on Wound Healing in Diabetic Mice Through Inhibition of STING Pathway Activation

Slow wound healing in diabetic patients is a common complication of diabetes. Autologous conditioned serum (ACS) therapy is an emerging and safe biological therapy, and may accelerate the wound healing in diabetes. To investigate the effect of ACS in promoting wound healing in diabetic mice and its possible mechanism. Twenty-four six-week-old male C57BL/6 J mice were selected and divided into 5 groups, including control group (Ctrl), diabetic wound group (DW), ACS treatment group (DW+ACS) and STING pathway validation group (DW+ACS+DMXAA), with six mice in each group. Intervention was initiated after the back incision was performed, and wound healing was assessed on day 0, day 7, and day 14, and wound healing was assessed by hematoxylin and eosin (HE) staining of skin tissue on day 14. At the same time, the wound healing of the fibroblast markers collagen I and α-SMA was measured by immunohistochemistry and western blot. ACS treatment significantly accelerated the diabetic wound according to the wound area and HE staining results. Meanwhile, collagen I and α-SMA concentration evaluated by immunohistochemistry and western blot were remarkably elevated under the ACS interference. The STING signaling pathway was obviously activated in diabetic wound tissues. After the addition of DMXAA, an agonist of STING, the healing function of ACS was dramatically reversed. The application of ACS promotes wound healing in diabetic mice by enhancing fibroblasts. Meanwhile, the STING signaling pathway was inactivated by ACS interference. Hence, ACS can be used in the treatment of wound healing of Diabetes.

Molecular mechanisms of ubiquitination in wound healing

Wound healing is a complex biological process involving multiple cellular and molecular mechanisms. Ubiquitination, a crucial post-translational modification, plays a vital role in regulating various aspects of wound healing through protein modification and degradation. This review comprehensively examines the molecular mechanisms of ubiquitination in wound healing, focusing on its regulation of inflammatory responses, macrophage polarization, angiogenesis, and the activities of fibroblasts and keratinocytes. We discuss how ubiquitination modifies key signaling pathways, including TGF-β/Smad3, NF-κB, and HIF-α, which are essential for proper wound healing. Understanding these mechanisms provides insights into potential therapeutic strategies for treating impaired wound healing, particularly in conditions such as diabetes. The review highlights recent advances in understanding ubiquitination's role in wound healing and discusses future research directions for developing targeted therapeutic approaches.

N 6-Methyladenosine Demethylase FTO Controls Macrophage Homeostasis in Diabetic Vasculopathy

Diabetic vasculopathy, encompassing complications such as diabetic retinopathy, represents a significant source of morbidity, with inflammation playing a pivotal role in the progression of these complications. This study investigates the influence of N6-methyladenosine demethylase (m6A) modification and the m6A demethylase fat mass and obesity-associated (FTO) protein on macrophage polarization and its subsequent effects on diabetic microvasculopathy. We found that diabetes induces a shift in macrophage polarization toward a proinflammatory M1 phenotype, which is associated with a reduction in m6A modification levels. Notably, FTO emerges as a critical regulator of m6A under diabetic conditions. In vitro experiments reveal that FTO not only modulates macrophage polarization but also mediates their interactions with vascular endothelial cells. In vivo experiments demonstrate that FTO deficiency exacerbates retinal inflammation and microvascular dysfunction in diabetic retinas. Mechanistically, FTO stabilizes mRNA through an m6A-YTHDF2-dependent pathway, thereby activating the PI3K/AKT signaling cascade. Collectively, these findings position FTO as a promising therapeutic target for the management of diabetic vascular complications.

ARTICLE HIGHLIGHTS

Promotion of chronic wound healing by plant-derived active ingredients and research progress and potential of plant polysaccharide hydrogels

Wound healing is a complex biochemical process. The use of herbal medicine in wound healing not only carries forward the wisdom of traditional medicine, with its anti-inflammatory and immune-regulating effects, but also reflects the direction of modern biopharmaceutical technology, such as its potential in developing new biomaterials like hydrogels. This article first outlines the inherent structural properties of healthy skin, along with the physiological characteristics related to chronic wounds in patients with diabetes and burns. Subsequently, the article delves into the latest advancements in clinical and experimental research on the impact of active constituents in herbal medicine on wound tissue regeneration, summarizing existing studies on the mechanisms of various herbal medicines in the healing of diabetic and burn wounds. Finally, the paper thoroughly examines the application and mechanisms of plant polysaccharide hydrogels containing active herbal compounds in chronic wound healing. The primary objective is to provide valuable resources for the clinical application and development of herbal medicine, thereby maximizing its therapeutic potential. It also represents the continuation of traditional medical wisdom, offering new possibilities for advancements in regenerative medicine and wound care.

Rhein promotes skin wound healing by activating the PI3K/AKT signaling pathway

Rhein is a natural anthraquinone substance extracted from Rheum palmatum L. This study aimed to evaluate Rhein's protective effects against skin wound by in vivo and in vitro models and investigate whether its protective mechanism regulated the PI3K/AKT signaling pathway. The skin wound mice model was established and then treated with Rhein for 10 days. Hematoxylin and eosin staining and Masson's trichrome staining were applied to assess histological changes and collagen maturity in the mice skin wound tissues. Human skin fibroblasts (HSFs) viability, migration, and invasion were detected by Cell counting kit-8 (CCK-8), scratch wound, and transwell assays respectively. Moreover, the protein expression of p-PI3K, PI3K, p-AKT, and AKT were determined by western blot assay. We found that local treatment with Rhein promoted skin wound healing and accelerated collagen maturation, compared with the Model group. In addition, Rhein promoted skin wound healing through accelerated HSF proliferation, migration, and invasion. Furthermore, Rhein remarkably enhanced p-PI3K and p-AKT expression, as well as p-PI3K/PI3K and p-AKT/AKT ratio in skin wound mice and HSF cells, suggesting that Rhein promoted skin wound healing by activating PI3K/AKT signaling pathway. In conclusion, Rhein is a promising agent for promoting wound healing of skin tissues.

Fish skin dressing for wound regeneration: A bioactive component review of omega-3 PUFAs, collagen and ECM

Wound healing is a complex biological process that involves several stages, including hemostasis, inflammation, proliferation, and remodeling. Traditional wound dressings, to a certain extent, can provide wound protection but are limited in promoting wound healing, reducing scar formation, and preventing bacterial infections. In recent years, with the advancement of research in biomedical materials, fish skin dressings have become a research hotspot in the field of tissue regeneration due to their remarkable biocompatibility and precious bioactive components. However, current research on fish skin dressings remains focused on clinical treatment. To further deepen and promote the development of fish skin dressings, we put emphasis on discussing main bioactive components in fish skin. This article has reviewed the advantages of fish skin dressings in wound regeneration, especially the promotive effects of its main bioactive components-Omega-3 polyunsaturated fatty acids, collagen derived from fish skin, and the extracellular matrix of fish skin-on the wound healing process. Besides, by critically summarizing the research issues of each bioactive component, this review assists researchers in better defining the next direction of research, thereby designing the optimal dressing for different types of wounds.

The Promoting Effect of Animal Bioactive Proteins and Peptide Components on Wound Healing: A Review

The skin is the first line of defense to protect the host from external environmental damage. When the skin is damaged, the wound provides convenience for the invasion of external substances. The prolonged nonhealing of wounds can also lead to numerous subsequent complications, seriously affecting the quality of life of patients. To solve this problem, proteins and peptide components that promote wound healing have been discovered in animals, which can act on key pathways involved in wound healing, such as the PI3K/AKT, TGF-β, NF-κ B, and JAK/STAT pathways. So far, some formulations for topical drug delivery have been developed, including hydrogels, microneedles, and electrospinning nanofibers. In addition, some high-performance dressings have been utilized, which also have great potential in wound healing. Here, research progress on the promotion of wound healing by animal-derived proteins and peptide components is summarized, and future research directions are discussed.

Sea Buckthorn Oil Promotes the PI3K-Akt-ERK Signaling Pathway and Macrophage M2 Polarization to Reduce Radiation-induced Skin Injury

In this work, we explored the role and mechanism of sea buckthorn oil in reducing radiation-induced skin damage. The radiation-induced rat skin injury model was established using strontium-90. Rats were treated with sea buckthorn oil twice a day postirradiation, and skin damage was observed at different times and evaluated using an injury score. Skin pathological changes were observed using hematoxylin and eosin (H&E) staining. Western blotting and immunohistochemistry were used to detect the expression of vascular growth and pathway proteins. ELISA was used to detect the secretion level of inflammatory factors. Immunohistochemistry was used to detect macrophage polarization marker proteins. We found that sea buckthorn oil can alleviate radiation-induced skin damage, accelerate skin vascular regeneration, and promote the up-regulation of vascular endothelial growth factor (VEGF) and its receptor (VEGFR). These results demonstrate the beneficial effects of sea buckthorn oil on radiation-induced skin damage. Furthermore, the levels of IL-1β and TNF-α in the sea buckthorn oil treatment group were significantly lower than those in the control group, while the levels of IL-4 and IL10 were significantly higher (P < 0.05). CD206 expression also increased in the sea buckthorn oil treatment group, while CD16 expression decreased compared to the control group (P < 0.05). Western blotting showed that PI3K, Akt and ERK expression increased in the sea buckthorn oil treatment group (P < 0.05). The beneficial effect of sea buckthorn oil in reducing the inflammatory response in irradiated rats was diminished when they were treated with PI3K inhibitor. We conclude that sea buckthorn oil may regulate macrophage M2 polarization by increasing the PI3K-Akt-ERK signaling pathway, thereby inhibiting the inflammatory response and promoting skin vascular regeneration to prevent and treat radiation-induced skin damage.

Tunicate cellulose nanocrystals strengthened injectable stretchable hydrogel as multi-responsive enhanced antibacterial wound dressing for promoting diabetic wound healing

The intricate microenvironment of diabetic wounds characterized by hyperglycemia, intense oxidative stress, persistent bacterial infection and complex pH fluctuations hinders the healing process. Herein, an injectable multifunctional hydrogel (QPTx) was developed, which exhibited excellent mechanical performance and triple responsiveness to pH, temperature, and glucose due to dynamic covalent cross-linking involving dynamic Schiff base bonds and phenylboronate esters with phenylboronic-modified quaternized chitosan (QCS-PBA), polydopamine coated tunicate cellulose crystals (PDAn@TCNCs) and polyvinyl alcohol (PVA). Furthermore, the hydrogels can incorporate insulin (INS) drugs to adapt to the complex and variable wound environment in diabetic patients for on-demand drug release that promote diabetic wound healing. Based on various excellent properties of the colloidal materials, the hydrogels were evaluated for self-healing, rheological and mechanical properties, in vitro insulin response to pH/temperature/glucose release, antibacterial, antioxidant, tissue adhesion, coagulation, hemostasis in vivo and in vitro, and biocompatibility and biodegradability. By introducing PDAn@TCNCs particles, the hydrogel has photothermal antibacterial activity, enhanced adhesion and oxidation resistance. We further demonstrated that these hydrogel dressings significantly improved the healing process compared to commercial dressings (Tegaderm™) in full-layer skin defect models. All indicated that the glucose-responsive QPTx hydrogel platform has great potential for treating diabetic wounds.

Pyroligneous extract, a biomaterial derived from pyrolytic palm kernel shell wood vinegar, as a novel diabetic wound healing aid: an animal study

OBJECTIVE

Wound in diabetes is difficult to heal since it possesses excessive inflammation. The aim of the study was to evaluate wound healing activity of chitosan-based hydrogel containing pyroligneous acid in diabetic animals.

SIGNIFICANCE

Pyroligneous acid, a byproduct of biochar production from palm kernel shell biomass, contained oxygenated compounds which, with extracting enrichment, could promote wound healing.

METHODS

Streptozotocin-induced diabetic male jcl: ICR mice were subjected to create wounds and treat with hydrogel containing pyroligneous extract at dose strengths of 0 (placebo), 100 and 150 µg/g-gel. Commercial gel (Intrasite®) was used as an active comparator. On 3-, 7-, 10- and 14-day post-wounding, wound contraction was rated and wound site tissues were collected. The specimens were H&E stained and microscopically examined to evaluate histological responses. The underline wound healing related cytokine and polypeptide expressions were determined using real-time PCR and western blot.

RESULTS

It was found that the extract accelerated the healing process in a dose-dependent manner where at dose strength of 150 µg/g-gel was as effective as active comparator. It increased gene expression of the cytokine and related proteins in TGF-β/SMAD signaling pathway and may further activate diabetic induced TGF-β downregulation to restore up to the level that healthy skin tissues express. It also enhanced the expressions of Akt, FAK, RhoA and Rac-1 and evidently activated phosphorylation of Akt and FAK.

CONCLUSION

The study demonstrated the extract could be a novel biomaterial for healing of such a chronic inflammatory wound as the wound in diabetes.

Role of macrophage polarization in periodontitis promoting atherosclerosis

Periodontitis is a chronic inflammatory destructive disease occurring in periodontal supporting tissues. Atherosclerosis(AS) is one of the most common cardiovascular diseases. Periodontitis can promote the development and progression of AS. Macrophage polarization is closely related to the development and progression of the above two diseases, respectively. The purpose of this animal study was to evaluate the effect of periodontitis on aortic lesions in atherosclerotic mice and the role of macrophage polarization in this process. 45 ApoE-/-male mice were randomly divided into three groups: control (NC), atherosclerosis (AS), and atherosclerosis with periodontitis (AS + PD). Micro CT, serological testing and pathological testing(hematoxylin-eosin staining, oil red O staining and Masson staining) were used for Evaluate the modeling situation. Immunohistochemistry(IHC) and immunofluorescence(IF) were performed to evaluate macrophage content and macrophage polarization in plaques. Cytokines associated with macrophage polarization were analyzed using quantitative real-time polymerase chain reaction(qRT-PCR) and enzyme-linked immunosorbent assay(Elisa). The expression of macrophages in plaques was sequentially elevated in the NC, AS, and AS + PD groups(P < 0.001). The expression of M1 and M1-related cytokines showed the same trend(P < 0.05). The expression of M2 and M2-related cytokines showed the opposite trend(P < 0.05). The rate of M1/M2 showed that AS + PD > AS > NC. Our preliminary data support that experimental periodontitis can increase the content of macrophage in aortic plaques to exacerbate AS. Meanwhile, experimental periodontitis can increase M1 macrophages, and decrease M2 macrophages, increasing M1/M2 in the plaque.

Understanding Macrophage Complexity in Metabolic Dysfunction-Associated Steatotic Liver Disease: Transitioning from the M1/M2 Paradigm to Spatial Dynamics

Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses metabolic dysfunction-associated fatty liver (MASL) and metabolic dysfunction-associated steatohepatitis (MASH), with MASH posing a risk of progression to cirrhosis and hepatocellular carcinoma (HCC). The global prevalence of MASLD is estimated at approximately a quarter of the population, with significant healthcare costs and implications for liver transplantation. The pathogenesis of MASLD involves intrahepatic liver cells, extrahepatic components, and immunological aspects, particularly the involvement of macrophages. Hepatic macrophages are a crucial cellular component of the liver and play important roles in liver function, contributing significantly to tissue homeostasis and swift responses during pathophysiological conditions. Recent advancements in technology have revealed the remarkable heterogeneity and plasticity of hepatic macrophage populations and their activation states in MASLD, challenging traditional classification methods like the M1/M2 paradigm and highlighting the coexistence of harmful and beneficial macrophage phenotypes that are dynamically regulated during MASLD progression. This complexity underscores the importance of considering macrophage heterogeneity in therapeutic targeting strategies, including their distinct ontogeny and functional phenotypes. This review provides an overview of macrophage involvement in MASLD progression, combining traditional paradigms with recent insights from single-cell analysis and spatial dynamics. It also addresses unresolved questions and challenges in this area.

Application of PPAR Ligands and Nanoparticle Technology in Metabolic Steatohepatitis Treatment

Metabolic dysfunction-associated steatotic liver disease/steatohepatitis (MASLD/MASH) is a major disease worldwide whose effective treatment is challenging. Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily and function as ligand-activated transcription factors. To date, three distinct subtypes of PPARs have been characterized: PPARα, PPARβ/δ, and PPARγ. PPARα and PPARγ are crucial regulators of lipid metabolism that modulate the transcription of genes involved in fatty acid (FA), bile acid, and cholesterol metabolism. Many PPAR agonists, including natural (FAs, eicosanoids, and phospholipids) and synthetic (fibrate, thiazolidinedione, glitazar, and elafibranor) agonists, have been developed. Furthermore, recent advancements in nanoparticles (NPs) have led to the development of new strategies for MASLD/MASH therapy. This review discusses the applications of specific cell-targeted NPs and highlights the potential of PPARα- and PPARγ-targeted NP drug delivery systems for MASLD/MASH treatment.

M2 macrophage-polarized anti-inflammatory microneedle patch for accelerating biofilm-infected diabetic wound healing via modulating the insulin pathway

Macrophages play a pivotal role in the healing of diabetic ulcers. The sustained elevation of glucose levels damages the insulin signaling pathway in macrophages, leading to dysfunctional macrophages that struggle to transition from pro-inflammatory (M1) to reparative (M2) states. Therefore, modulating macrophage inflammatory responses via the insulin pathway holds promise for diabetic ulcer treatment. Additionally, the presence of biofilm impedes drug penetration, and the resulting immunosuppressive microenvironment exacerbates the persistent infiltration of pro-inflammatory M1 macrophages. Therefore, we designed an array of dissolvable microneedle (denoted as NPF@MN) loaded with self-assembled nanoparticles that could deliver NPF nanoparticles, acid-sensitive NPF-releasing Protocatechualdehyde (PA) with hypoglycemic and insulin-like effects, regulating macrophage polarization to an anti-inflammatory M2 phenotype. Additionally, this study extensively examined the mechanism by which NPF@MN accelerates the healing of diabetic ulcers through the activation of the insulin signaling pathway. Through RNA-seq and GSEA analysis, we identified a reduction in the expression of pathway-related factors such as IR, IRS-1, IRS-2, and SHC. Our work presents an innovative therapeutic approach targeting the insulin pathway in diabetic ulcers and underscores its translational potential for clinical management.

LDHA-mediated M2-type macrophage polarization via tumor-derived exosomal EPHA2 promotes renal cell carcinoma progression

Lactate dehydrogenase A (LDHA) is known to promote the growth and invasion of various types of tumors, affects tumor resistance, and is associated with tumor immune escape. But how LDHA reshapes the tumor microenvironment and promotes the progression of renal cell carcinoma (RCC) remains unclear. In this study, we found that LDHA was highly expressed in clear cell RCC (ccRCC), and this high expression was associated with macrophage infiltration, while macrophages were highly infiltrated in ccRCC, affecting patient prognosis via M2-type polarization. Our in vivo and in vitro experiments demonstrated that LDHA and M2-type macrophages could enhance the proliferation, invasion, and migration abilities of ccRCC cells. Mechanistically, high expression of LDHA in ccRCC cells upregulated the expression of EPHA2 in exosomes derived from renal cancer. Exosomal EPHA2 promoted M2-type polarization of macrophages by promoting activation of the PI3K/AKT/mTOR pathway in macrophages, thereby promoting the progression of ccRCC. All these findings suggest that EPHA2 may prove to be a potential therapeutic target for advanced RCC.

Exploring the active components and potential mechanisms of Alpiniae oxyphyllae Fructus in treating diabetes mellitus with depression by UPLC-Q-Exactive Orbitrap/MS, network pharmacology and molecular docking

The growing incidence of diabetes mellitus (DM) and depression is a global public health issue. Alpiniae oxyphyllae Fructus (AOF) is a kind of medicinal and edible plant which be found with anti-diabetic property, and could improve depression-like symptoms. This study aimed to screen active targets and potential mechanisms of AOF in treating DM with depression. Injection of streptozotocin (STZ) and exposure to chronic unpredictable mild stress (CUMS) for 4 weeks were used to conduct the DM with depression mice model. Behavioral tests, indexes of glucose metabolism, monoamine neurotransmitters, inflammatory cytokine and oxidative stress were measured. Histopathological change of hippocampus tissue was observing by HE and Nissl staining. UPLC-Q-Exactive Orbitrap/MS, network pharmacology and molecular docking were used to explore the chemical components and mechanisms of AOF on the DM with depression. AOF showed a reversed effect on body weight in DM with depression mice. Glucose metabolism and insulin resistance could be improved by treatment of AOF. In addition, AOF could alleviate depression-like behaviors based on the results of behavior tests and monoamine neurotransmitters. AOF also attenuated STZ-CUMS induced neuron injury in hippocampus. Next, a total of 61 chemical components were identified in the UPLC-Q-Exactive Orbitrap/MS analysis of the extract of AOF. Network pharmacology analysis suggested that 12 active components and 227 targets were screened from AOF, and 1802 target genes were screened from DM with depression, finally 126 intersection target genes were obtained. Drug-disease targets network was constructed and implied that the top five components with a higher degree value includes quercetin, nootkatone, baicalein, (-)-epicatechin and nootkatol. Protein-protein interaction (PPI) network showed that MAPK1, FOS, AKT1, IL6 and TP53 may be the core intersection targets. The mechanism of the effect of AOF on DM with depression was analyzed through gene ontology (GO), and kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, mainly involved in AGE/RAGE, PI3K/AKT, and MAPK signaling pathways. The results of molecular docking indicated that quercetin, nootkatone, baicalein, (-)-epicatechin and nootkatol all had good binding to the core intersection targets. Overall, our experimental researches have demonstrated that AOF could exert the dual effects of anti-diabetic and anti-depression on DM with depression mice, through multi-targets and multi-pathways.

Macrophage plasticity: signaling pathways, tissue repair, and regeneration

Macrophages are versatile immune cells with remarkable plasticity, enabling them to adapt to diverse tissue microenvironments and perform various functions. Traditionally categorized into classically activated (M1) and alternatively activated (M2) phenotypes, recent advances have revealed a spectrum of macrophage activation states that extend beyond this dichotomy. The complex interplay of signaling pathways, transcriptional regulators, and epigenetic modifications orchestrates macrophage polarization, allowing them to respond to various stimuli dynamically. Here, we provide a comprehensive overview of the signaling cascades governing macrophage plasticity, focusing on the roles of Toll-like receptors, signal transducer and activator of transcription proteins, nuclear receptors, and microRNAs. We also discuss the emerging concepts of macrophage metabolic reprogramming and trained immunity, contributing to their functional adaptability. Macrophage plasticity plays a pivotal role in tissue repair and regeneration, with macrophages coordinating inflammation, angiogenesis, and matrix remodeling to restore tissue homeostasis. By harnessing the potential of macrophage plasticity, novel therapeutic strategies targeting macrophage polarization could be developed for various diseases, including chronic wounds, fibrotic disorders, and inflammatory conditions. Ultimately, a deeper understanding of the molecular mechanisms underpinning macrophage plasticity will pave the way for innovative regenerative medicine and tissue engineering approaches.

The association between vitamin D and the progression of diabetic nephropathy: insights into potential mechanisms

Aims

Vitamin D deficiency (VDD) is prevalent in the population, with inadequate intake, impaired absorption and metabolism as the main causative factors. VDD increases the risk of developing chronic diseases such as type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN), but the molecular mechanisms underlying this phenomenon are not known. The aim of this study was to investigate the association and potential mechanisms of vitamin D levels with the progression of DN by analyzing general clinical data and using bioinformatics methods.

Methods

The study included 567 diabetes mellitus type 2 (T2DM) patients from the Rocket Force Characteristic Medical Center as the case group and 221 healthy examinees as the normal control group. T2DM patients were categorized into T2DM, early diabetic nephropathy (EDN), and advanced diabetic nephropathy (ADN) based on the progression of diabetic nephropathy. The renal RNA-seq and scRNA-seq data of patients with DN were mined from public databases, and the differential expression of vitamin D-related genes in normal-EDN-ADN was analyzed by bioinformatics method, protein interaction network was constructed, immune infiltration was evaluated, single cell map was drawn, and potential mechanisms of VD and DN interaction were explored.

Results

Chi-square test showed that vitamin D level was significantly negatively correlated with DN progression (p < 0.001). Bioinformatics showed that the expression of vitamin D-related cytochrome P450 family genes was down-regulated, and TLR4 and other related inflammatory genes were abnormally up-regulated with the progression of DN. Vitamin D metabolism disturbance up-regulate "Nf-Kappa B signaling pathway," B cell receptor signaling pathway and other immune regulation and insulin resistance related pathways, and inhibit a variety of metabolic pathways. In addition, vitamin D metabolism disturbance are strongly associated with the development of diabetic cardiomyopathy and several neurological disease complications.

Conclusion

VDD or vitamin D metabolism disturbance is positively associated with the severity of renal injury. The mechanisms may involve abnormal regulation of the immune system by vitamin D metabolism disturbance, metabolic suppression, upregulation of insulin resistance and inflammatory signalling pathways.

Celastrol alleviates airway hyperresponsiveness and inflammation in obese asthma through mediation of alveolar macrophage polarization

Obese asthma is a unique asthma phenotype that decreases sensitivity to inhaled corticosteroids, and currently lacks efficient therapeutic medication. Celastrol, a powerful bioactive substance obtained naturally from the roots of Tripterygium wilfordii, has been reported to possess the potential effect of weight loss in obese individuals. However, its role in the treatment of obese asthma is not fully elucidated. In the present study, diet-induced obesity (DIO) mice were used with or without ovalbumin (OVA) sensitization, the therapeutic effects of celastrol on airway hyperresponsiveness (AHR) and airway inflammation were examined. We found celastrol significantly decreased methacholine-induced AHR in obese asthma, as well as reducing the infiltration of inflammatory cells and goblet cell hyperplasia in the airways. This effect was likely due to the inhibition of M1-type alveolar macrophages (AMs) polarization and the promotion of M2-type macrophage polarization. In vitro, celastrol yielded equivalent outcomes in Lipopolysaccharide (LPS)-treated RAW264.7 macrophage cells, featuring a reduction in the expression of M1 macrophage makers (iNOS, IL-1β, TNF-α) and heightened M2 macrophage makers (Arg-1, IL-10). Mechanistically, the PI3K/AKT signaling pathway has been implicated in these processes. In conclusion, we demonstrated that celastrol assisted in mitigating various parameters of obese asthma by regulating the balance of M1/M2 AMs polarization.

Relieving Macrophage Dysfunction by Inhibiting SREBP2 Activity: A Hypoxic Mesenchymal Stem Cells-Derived Exosomes Loaded Multifunctional Hydrogel for Accelerated Diabetic Wound Healing

Macrophage dysfunction is one of the primary factors leading to the delayed healing of diabetic wounds. Hypoxic bone marrow mesenchymal stem cells-derived exosomes (hyBMSC-Exos) have been shown to play an active role in regulating cellular function through the carried microRNAs. However, the administration of hyBMSC-Exos alone in diabetic wounds usually brings little effect, because the exosomes are inherently unstable and have a short retention time at the wounds. In this study, a multifunctional hydrogel based on gallic acid (GA) conjugated chitosan (Chi-GA) and partially oxidized hyaluronic acid (OHA) is prepared for sustained release of hyBMSC-Exos. The hydrogel not only exhibits needs-satisfying physicochemical properties, but also displays outstanding biological performances such as low hemolysis rate, strong antibacterial capacity, great antioxidant ability, and excellent biocompatibility. It has the ability to boost the stability of hyBMSC-Exos, leading to a continuous and gradual release of the exosomes at wound locations, ultimately enhancing the exosomes' uptake efficiency by target cells. Most importantly, hyBMSC-Exos loaded hydrogel shows an excellent ability to promote diabetic wound healing by regulating macrophage polarization toward M2 phenotype. This may be because exosomal miR-4645-5p and antioxidant property of the hydrogel synergistically inhibit SREBP2 activity in macrophages. This study presents a productive approach for managing diabetic wounds.

Exosomes from adipose-derived stem cells regulate macrophage polarization and accelerate diabetic wound healing via the circ-Rps5/miR-124-3p axis

BACKGROUND

Adipose-derived stem cells (ADSCs) hold promising application prospects in the treatment of diabetic wounds, although the underlying mechanisms of repair have not been fully elucidated. This research aimed to elucidate the mechanisms by which ADSCs promote wound healing.

METHODS

Exosomes from ADSCs were isolated and circRps5 level was identified. To investigate the role of circRps5 in the regulation, exosomes from differently treated ADSCs were used. Different exosomes were injected into the edge of the wound in diabetic mice, and the effects on wound healing status, pathology, collagen, cytokines, and macrophage phenotype were assessed. Raw264.7 cells were co-treated with high glucose and exosomes, and then cell phenotype and autophagy were examined in vitro, followed by the evaluation of miR-124-3p's impact on cell phenotype.

RESULTS

Exosomes from ADSCs were isolated and identified using nanoparticle tracking analysis and exosome markers. Overexpression of circRps5 accelerated wound healing, reduced inflammatory response, enhanced collagen production, and promoted the M2 transformation of macrophages. In high glucose-induced macrophages, its overexpression also inhibited excessive autophagy. When macrophages overexpressed miR-124-3p, the induction of the M2 phenotype was suppressed. Luciferase reporter assay proved the combination of circRps5 and miR-124-3p.

CONCLUSION

This study identifies that circRps5 carried by ADSC-Exos promotes macrophage M2 polarization through miR-124-3p. These findings provide valuable insights into the mechanism of ADSC-Exos for treating refractory diabetic wounds, laying a solid theoretical groundwork for future clinical development.

The Pivotal Role of Macrophages in the Pathogenesis of Pancreatic Diseases

The pancreas is an organ with both exocrine and endocrine functions, comprising a highly organized and complex tissue microenvironment composed of diverse cellular and non-cellular components. The impairment of microenvironmental homeostasis, mediated by the dysregulation of cell-to-cell crosstalk, can lead to pancreatic diseases such as pancreatitis, diabetes, and pancreatic cancer. Macrophages, key immune effector cells, can dynamically modulate their polarization status between pro-inflammatory (M1) and anti-inflammatory (M2) modes, critically influencing the homeostasis of the pancreatic microenvironment and thus playing a pivotal role in the pathogenesis of the pancreatic disease. This review aims to summarize current findings and provide detailed mechanistic insights into how alterations mediated by macrophage polarization contribute to the pathogenesis of pancreatic disorders. By analyzing current research comprehensively, this article endeavors to deepen our mechanistic understanding of regulatory molecules that affect macrophage polarity and the intricate crosstalk that regulates pancreatic function within the microenvironment, thereby facilitating the development of innovative therapeutic strategies that target perturbations in the pancreatic microenvironment.

The effect of macrophages and their exosomes in ischemic heart disease

Ischemic heart disease (IHD) is a leading cause of disability and death worldwide, with immune regulation playing a crucial role in its pathogenesis. Various immune cells are involved, and as one of the key immune cells residing in the heart, macrophages play an indispensable role in the inflammatory and reparative processes during cardiac ischemia. Exosomes, extracellular vesicles containing lipids, nucleic acids, proteins, and other bioactive molecules, have emerged as important mediators in the regulatory functions of macrophages and hold promise as a novel therapeutic target for IHD. This review summarizes the regulatory mechanisms of different subsets of macrophages and their secreted exosomes during cardiac ischemia over the past five years. It also discusses the current status of clinical research utilizing macrophages and their exosomes, as well as strategies to enhance their therapeutic efficacy through biotechnology. The aim is to provide valuable insights for the treatment of IHD.

Traditional Chinese medicine in regulating macrophage polarization in immune response of inflammatory diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Numerous studies have demonstrated that various traditional Chinese medicines (TCMs) exhibit potent anti-inflammatory effects against inflammatory diseases mediated through macrophage polarization and metabolic reprogramming.

AIM OF THE STUDY

The objective of this review was to assess and consolidate the current understanding regarding the pathogenic mechanisms governing macrophage polarization in the context of regulating inflammatory diseases. We also summarize the mechanism action of various TCMs on the regulation of macrophage polarization, which may contribute to facilitate the development of natural anti-inflammatory drugs based on reshaping macrophage polarization.

MATERIALS AND METHODS

We conducted a comprehensive review of recently published articles, utilizing keywords such as "macrophage polarization" and "traditional Chinese medicines" in combination with "inflammation," as well as "macrophage polarization" and "inflammation" in conjunction with "natural products," and similar combinations, to search within PubMed and Google Scholar databases.

RESULTS

A total of 113 kinds of TCMs (including 62 components of TCMs, 27 TCMs as well as various types of extracts of TCMs and 24 Chinese prescriptions) was reported to exert anti-inflammatory effects through the regulation of key pathways of macrophage polarization and metabolic reprogramming.

CONCLUSIONS

In this review, we have analyzed studies concerning the involvement of macrophage polarization and metabolic reprogramming in inflammation therapy. TCMs has great advantages in regulating macrophage polarization in treating inflammatory diseases due to its multi-pathway and multi-target pharmacological action. This review may contribute to facilitate the development of natural anti-inflammatory drugs based on reshaping macrophage polarization.

Epigenetic modification: A novel insight into diabetic wound healing

Wound healing is an intricate and fine regulatory process. In diabetic patients, advanced glycation end products (AGEs), excessive reactive oxygen species (ROS), biofilm formation, persistent inflammation, and angiogenesis regression contribute to delayed wound healing. Epigenetics, the fast-moving science in the 21st century, has been up to date and associated with diabetic wound repair. In this review, we go over the functions of epigenetics in diabetic wound repair in retrospect, covering transcriptional and posttranscriptional regulation. Among these, we found that histone modification is widely involved in inflammation and angiogenesis by affecting macrophages and endothelial cells. DNA methylation is involved in factors regulation in wound repair but also affects the differentiation phenotype of cells in hyperglycemia. In addition, noncodingRNA regulation and RNA modification in diabetic wound repair were also generalized. The future prospects for epigenetic applications are discussed in the end. In conclusion, the study suggests that epigenetics is an integral regulatory mechanism in diabetic wound healing.

Polyphenols: immunonutrients tipping the balance of immunometabolism in chronic diseases

Mounting evidence progressively appreciates the vital interplay between immunity and metabolism in a wide array of immunometabolic chronic disorders, both autoimmune and non-autoimmune mediated. The immune system regulates the functioning of cellular metabolism within organs like the brain, pancreas and/or adipose tissue by sensing and adapting to fluctuations in the microenvironment's nutrients, thereby reshaping metabolic pathways that greatly impact a pro- or anti-inflammatory immunophenotype. While it is agreed that the immune system relies on an adequate nutritional status to function properly, we are only just starting to understand how the supply of single or combined nutrients, all of them termed immunonutrients, can steer immune cells towards a less inflamed, tolerogenic immunophenotype. Polyphenols, a class of secondary metabolites abundant in Mediterranean foods, are pharmacologically active natural products with outstanding immunomodulatory actions. Upon binding to a range of receptors highly expressed in immune cells (e.g. AhR, RAR, RLR), they act in immunometabolic pathways through a mitochondria-centered multi-modal approach. First, polyphenols activate nutrient sensing via stress-response pathways, essential for immune responses. Second, they regulate mammalian target of rapamycin (mTOR)/AMP-activated protein kinase (AMPK) balance in immune cells and are well-tolerated caloric restriction mimetics. Third, polyphenols interfere with the assembly of NLR family pyrin domain containing 3 (NLRP3) in endoplasmic reticulum-mitochondria contact sites, inhibiting its activation while improving mitochondrial biogenesis and autophagosome-lysosome fusion. Finally, polyphenols impact chromatin remodeling and coordinates both epigenetic and metabolic reprogramming. This work moves beyond the well-documented antioxidant properties of polyphenols, offering new insights into the multifaceted nature of these compounds. It proposes a mechanistical appraisal on the regulatory pathways through which polyphenols modulate the immune response, thereby alleviating chronic low-grade inflammation. Furthermore, it draws parallels between pharmacological interventions and polyphenol-based immunonutrition in their modes of immunomodulation across a wide spectrum of socioeconomically impactful immunometabolic diseases such as Multiple Sclerosis, Diabetes (type 1 and 2) or even Alzheimer's disease. Lastly, it discusses the existing challenges that thwart the translation of polyphenols-based immunonutritional interventions into long-term clinical studies. Overcoming these limitations will undoubtedly pave the way for improving precision nutrition protocols and provide personalized guidance on tailored polyphenol-based immunonutrition plans.

Unremitting pro-inflammatory T-cell phenotypes, and macrophage activity, following paediatric burn injury

Objectives

The aim of this study was to characterise the dynamic immune profile of paediatric burn patients for up to 18 months post-burn.

Methods

Flow cytometry was used to measure 25 cell markers, chemokines and cytokines which reflected both pro-inflammatory and anti-inflammatory immune profiles. Peripheral blood mononuclear cells from 6 paediatric burn patients who had returned for repeated burn and scar treatments for > 4 timepoints within 12 months post-burn were compared to four age-matched healthy controls.

Results

While overall proportions of T cells, NK cells and macrophages remained relatively constant, over time percentages of these immune cells differentiated into effector and proinflammatory cell phenotypes including Th17 and activated γδ T cells. Circulating proportions of γδ T cells increased their expression of pro-inflammatory mediators throughout the burn recovery, with a 3-6 fold increase of IL-17 at 1-3 weeks, and NFκβ 9-18 months post-burn. T-regulatory cell plasticity was also observed, and Treg phenotype proportions changed from systemically reduced skin-homing T-regs (CCR4+) and increased inflammatory (CCR6+) at 1-month post-burn, to double-positive cell types (CCR4+CCR6+) elevated in circulation for 18 months post-burn. Furthermore, Tregs were observed to proportionally express less IL-10 but increased TNF-α over 18 months.

Conclusion

Overall, these results indicate the circulating percentages of immune cells do not increase or decrease over time post-burn, instead they become highly specialised, inflammatory and skin-homing. In this patient population, these changes persisted for at least 18 months post-burn, this 'immune distraction' may limit the ability of immune cells to prioritise other threats post-burn, such as respiratory infections.

Protective Factors and the Pathogenesis of Complications in Diabetes

Chronic complications of diabetes are due to myriad disorders of numerous metabolic pathways that are responsible for most of the morbidity and mortality associated with the disease. Traditionally, diabetes complications are divided into those of microvascular and macrovascular origin. We suggest revising this antiquated classification into diabetes complications of vascular, parenchymal, and hybrid (both vascular and parenchymal) tissue origin, since the profile of diabetes complications ranges from those involving only vascular tissues to those involving mostly parenchymal organs. A major paradigm shift has occurred in recent years regarding the pathogenesis of diabetes complications, in which the focus has shifted from studies on risks to those on the interplay between risk and protective factors. While risk factors are clearly important for the development of chronic complications in diabetes, recent studies have established that protective factors are equally significant in modulating the development and severity of diabetes complications. These protective responses may help explain the differential severity of complications, and even the lack of pathologies, in some tissues. Nevertheless, despite the growing number of studies on this field, comprehensive reviews on protective factors and their mechanisms of action are not available. This review thus focused on the clinical, biochemical, and molecular mechanisms that support the idea of endogenous protective factors, and their roles in the initiation and progression of chronic complications in diabetes. In addition, this review also aimed to identify the main needs of this field for future studies.