MSC-released TGF-β regulate α-SMA expression of myofibroblast during wound healing

Extracellular matrix modulating effects of amnion-derived mesenchymal stem cells on aging skin wounds in α-Klotho knockout mice

AIM

Wounds in the elderly are frequently recalcitrant and chronic as a result of the effects of skin aging and associated complications. The objective of this study is to utilize an α-Klotho knockout (KO) mice wound model to assess the capacity of amnion-derived mesenchymal stem cells (AMSCs) to facilitate wound healing in aging skin.

METHODS

AMSCs were applied topically to the wound after extraction and gelatinization of the conditioned medium (CM). Animal experiments were performed with two distinct mouse strains: α-Klotho KO mice and wild-type mice. Full-thickness skin defect models with a diameter of 8 mm were created by incising the skin on the left and right sides of the dorsum. On day 8 after wound creation, the mice were sacrificed, and wound tissue was collected for analysis through histological and immunohistochemical evaluations, as well as through quantitative polymerase chain reaction.

RESULTS

The topical application of CM gel to wounds of α-Klotho KO mice demonstrated that wound healing was significantly higher than that observed in control, reaching the wound closure rate of wild-type mice on day 8. Additionally, gene expression analysis of wound tissue indicated that AMSC-CM may regulate extracellular matrix formation and fibrosis. Moreover, histological analysis indicated that AMSC-CM may facilitate wound contraction of aging skin wounds of α-Klotho KO mice by inducing myofibroblast differentiation and promoting granulation and collagen formation, which are the primary components of the extracellular matrix.

CONCLUSIONS

AMSC-CM may facilitate wound healing in aging skin of α-Klotho KO mice by regulating the extracellular matrix. Geriatr Gerontol Int 2025; 25: 701-708.

Engineered Titanium Oxide Nanoplatform for Targeted Photodynamic/Photothermal-Gas Therapy in Keloid Treatment

Keloids pose a considerable worldwide health issue owing to their continual proliferation, invasiveness, and elevated recurrence rates. Keloids are abnormal scars formed through dysregulated wound healing processes, characterized by excessive keloid fibroblast (KF) proliferation, irregular collagen deposits, and persistent reticular dermis inflammation, which can lead to limited joint mobility, psychological distress, and severe pain and itching. In this study, we present metal-organic framework (MOF)-derived TiO2-based nanoparticles (LA@CTx NPs) synthesized as a phototherapy-gas-therapy nanoplatform, which have the ability to break down collagen, reduce inflammation, and stop the overproliferation of keloid fibroblasts. The MIL-125-derived nanoparticles maintain their crystalline framework while being rich in oxygen vacancies (OVs) and l-arginine (LA), enabling efficient photothermal conversion and reactive oxygen species (ROS) generation driven by synergistic near-infrared (NIR). Importantly, ROS generated by the NPs can trigger nitric oxide (NO) production by oxidizing LA, with the concentration of NO finely tunable via modulation of light conditions. This allows for a dual therapeutic effect: low NO concentrations suppress inflammation, while higher concentrations induce cell death. In vitro and in vivo investigations show that LA@CTx nanoparticles efficiently eliminate primary keloid lesions and provoke apoptosis in keloid cells by dual-modality activation of photodynamic and photothermal treatments facilitated by single NIR irradiation. The study presents an innovative method of therapy for the clinical treatment of keloids.

Friedelin: A natural compound exhibited potent antibacterial, anti-inflammatory, and wound healing properties against MRSA-infected wounds

Methicillin-resistant Staphylococcus aureus (MRSA) is primarily recognized as a pathogen responsible for skin, soft tissue, and multiple organs infection. The colonization of the skin and mucous membranes by hypervirulent resistant bacteria like MRSA during hospitalization significantly contributes to life-threatening conditions. Friedelin (FRN) is a pentacyclic triterpene (C30H50O) isolated from Euphorbia grantii Oliv. The current work aims to determine the efficacy of FRN against MRSA-infected wounds in mice besides the in vitro study to evaluate its bactericidal activity. The in vitro study revealed that FRN was strongly active against MRSA which had a wide zone of MRSA growth inhibition and promising minimum inhibitory concentration (MIC). Moreover, FRN downregulated the major virulence genes seb and icaD, responsible for the production of staphylococcal enterotoxin SED and biofilm formation, respectively in contrast to the untreated group. The dressing of MRSA-infected wound with 40 ppm FRN significantly reduced the wound size and bacterial count and accelerated the process of wound healing which had a higher immune expression of both VEGF (vascular endothelial growth factor) and α-SMA (alpha smooth muscle actin) compared with other treated groups. Additionally, FRN could reduce the inflammatory response of MRSA in a dose-dependent manner by downregulating the TNF-α (tumor necrosis factor-α) and PGS-2 (prostaglandin synthase-2) gene expression levels. FRN is effective against MRSA-infected wounds via its potent bactericidal and anti-inflammatory activities that accelerate angiogenesis and wound maturation.

Conductive Hybrid Hydrogel of Carbon Nanotubes-Protein-Cellulose: In Vivo Treatment of Diabetic Wound via Photothermal Therapy and Tracking Real-Time Wound Assessment via Photoacoustic Imaging

Diabetic wounds pose significant challenges in healthcare due to their slow healing rates and susceptibility to infections, leading to severe complications. In this study, we developed a carbon nanotube-based conductive protein-cellulose hydrogel designed to enhance wound healing through photothermal therapy. The hydrogel's unique properties, including high electrical conductivity and biocompatibility, were assessed in vitro for cell viability, hemolysis, and histological evaluations. In vivo studies on diabetic rats revealed that the hydrogel significantly improved wound healing, with faster wound closure rates. These results were supported by noticeable reductions in inflammatory markers and enhanced blood vessel formation, as observed through immunohistochemical analysis. Additionally, photoacoustic imaging offered real-time data on blood flow and tissue oxygen levels, showing positive trends in the healing process. Overall, these findings point to the potential of this conductive hydrogel, especially when paired with photothermal therapy, to serve as an effective treatment for diabetic wounds, offering promising possibilities in wound care strategies.

Comparative effects of various extracellular vesicle subpopulations derived from clonal mesenchymal stromal cells on cultured fibroblasts in wound healing-related process

INTRODUCTION

Non-healing wounds pose significant challenges and require effective therapeutic interventions. Extracellular vesicles (EVs) have emerged as promising cell-free therapeutic agents in tissue regeneration. However, the functional differences between different subpopulations of EVs in wound healing remain understudied. This study aimed to evaluate the effects of two distinct subpopulations of clonal mesenchymal stromal cells (cMSC)-derived EVs (cMSC-EVs), namely 20 K and 110K-cMSC-EVs, primarily on in vitro wound healing process, providing fast and cost-effective alternatives to animal models.

METHODS

In vitro assays were conducted to compare the effects of 20 K and 110K-cMSC-EVs, isolated through high-speed centrifugation and differential ultracentrifugation, respectively. For evaluation the main mechanisms of wound healing, including cell proliferation, cell migration, angiogenesis, and contraction. Human dermal fibroblasts (HDF) were considered as the main cells for analysis of these procedures. Moreover, gene expression analysis was performed to assess the impact of these EV subpopulations on the related process of wound healing on HDF.

RESULTS

The results demonstrated that both 20 K and 110K-cMSC-EVs exhibited beneficial effects on cell proliferation, cell migration, angiogenesis, and gel contraction. RT-qPCR revealed that both EV types downregulated interleukin 6 (IL6), induced proliferation by upregulating proliferating cell nuclear antigen (PCNA), and regulated remodeling by upregulating matrix metallopeptidase 1 (MMP1) and downregulating collagen type 1 (COL1).

DISCUSSION

This study highlights the effects of both 20 K and 110K-cMSC-EVs on the potency of HDFs in wound healing-related process. As the notable finding, 20K-cMSC-EVs offer a more feasible and cost-effective subpopulation for isolation and follow the GMP standard, recommended to utilize this fraction for therapeutic application.

Exploring Isotretinoin's Unexpected Acceleration of wound Healing: A rat model study

BACKGROUND

There have been clinical observations indicating that wound healing could be affected in patients undergoing systemic isotretinoin treatment. However, the precise role of retinoids in wound healing is still unclear and controversial. It is generally assumed that systemic retinoids could be harmful to wound healing, but this requires further investigation.

METHODS

Sprague-Dawley rats were gavaged with 2 mg/Kg/day of Isotretinoin and divided into three groups: Control, Isotretinoin/1month and Isotretinoin/2month. Photographic documentation and histomorphometric investigation were performed. The mRNA expressions of IL-6, MCP-1, VEGF, ICAM1, L-Selectin, TGF-1β, IL-10, IL-1α, and IL-8 were examined by qRT-PCR.

RESULTS

There was no significant impact on the rate of wound closure in Isotretinoin/1month group. However, a two-month regimen accelerated the wound-healing process. RT-PCR results revealed increased expression of IL-6, IL-8, IL-1α, TGF-β1, IL-10 MCP-1, ICAM1, L-Selectin, and VEGF rats that were administered Isotretinoin. Histological observations showed an increased number of mast cells in the wound areas of rats treated with Isotretinoin.

CONCLUSION

Our research indicated that taking Isotretinoin did not slow down wound healing and may even help the growth phase. Additionally, we did not observe any keloid formation during our histopathological analysis, suggesting that it may not be necessary to postpone invasive surgical procedures for six months after Isotretinoin therapy.

Pharmacological effects of triamcinolone associated with surgical glue on cutaneous wound healing in rats

PURPOSE

The surgical glue is widely used in closing cutaneous surgical wounds. Corticosteroids are indicated for their anti-inflammatory and immunomodulatory properties. The present work evaluated the pharmacological effects of triamcinolone (AT) incorporated into surgical glue (C) on the initial phase of the wound healing process in Wistar rats.

METHODS

Through in-vivo studies, the effects of the healing process, C or C+AT in the same rat were evaluated for seven and 14 days post-surgery.

RESULTS

The C+AT association did not change the physicochemical properties of the polymer. This association in wound healing confirmed the anti-inflammatory and immunomodulatory effects of the corticosteroid, with less neovascularization and fibrosis, in addition to the remodeling of the extracellular matrix carried out by the balance of myofibroblasts and less dense collagen fibers, culminating in tissue regeneration and possible reduction of side effects.

CONCLUSION

This association is a powerful and innovative pharmacological tool, promising in translational medicine.

Cellular crosstalk in the bone marrow niche

The bone marrow niche is a special microenvironment that comprises elements, including hematopoietic stem cells, osteoblasts, and endothelial cells, and helps maintain their characteristic functions. Here, we elaborate on the crosstalk between various cellular components, hematopoietic stem cells, and other cells in the bone marrow niche. We further explain the mechanism of preserving equilibrium in the bone marrow niche, which is crucial for the directional regulation of bone reconstruction and repair. Additionally, we elucidate the intercommunication among osteocytes, the regulation of osteoblast maturation and activation by lymphocytes, the deficiency of megakaryocytes that can markedly impair osteoblast formation, and the mechanism of interaction between macrophages and mesenchymal stem cells in the bone marrow niche. Finally, we discussed the new immunotherapies for bone tumors in the BM niche. In this review, we aimed to provide a candid overview of the crosstalk among bone marrow niche cells and to highlight new concepts underlying the unknown mechanisms of hematopoiesis and bone reconstruction. Thus, this review may provide a more comprehensive understanding of the role of these niche cells in improving hematopoietic function and help identify their therapeutic potential for different diseases in the future.

Transplanted artificial amnion membrane enhanced wound healing in third-degree burn injury diabetic mouse model

Introduction

Wound healing is severely compromised in patients with diabetes owing to factors such poor blood circulation, delayed immune response, elevated blood sugar levels, and neuropathy. Although the development of new wound healing products and prevention of serious complications such as infections in wounds have received substantial interest, wound healing remains a challenge in regenerative medicine. Burn wounds, especially third-degree burns, are difficult to treat because they are associated with immune and inflammatory reactions and distributive shock. Wound care and treatment that protects the burn site from infection and allows wound healing can be achieved with bioengineered wound dressings. However, few studies have reported effective dressings for third-degree burn wounds, making it important to develop new dressing materials.

Methods

In this study, we developed an artificial amniotic membrane (AM) using epithelial and mesenchymal cells derived from human amnion as a novel dressing material. The artificial AM was applied to the wound of a diabetic third-degree burn model and its wound healing ability was evaluated.

Results

This artificial amnion produced multiple growth factors associated with angiogenesis, fibroblast proliferation, and anti-inflammation. In addition, angiogenesis and granulation tissue formation were promoted in the artificial AM-treated mouse group compared with the control group. Furthermore, the inflammatory phase was prolonged in the control group.

Conclusions

Our preliminary results indicate that the artificial AM might be useful as a new dressing for refractory ulcers and third-degree burns. This artificial AM-based material represents great potential for downstream clinical research and treatment of diabetes patients with third-degree burns.

Emerging technologies in regenerative medicine: The future of wound care and therapy

Wound healing, an intricate biological process, comprises orderly phases of simple biological processed including hemostasis, inflammation, angiogenesis, cell proliferation, and ECM remodeling. The regulation of the shift in these phases can be influenced by systemic or environmental conditions. Any untimely transitions between these phases can lead to chronic wounds and scarring, imposing a significant socio-economic burden on patients. Current treatment modalities are largely supportive in nature and primarily involve the prevention of infection and controlling inflammation. This often results in delayed healing and wound complications. Recent strides in regenerative medicine and tissue engineering offer innovative and patient-specific solutions. Mesenchymal stem cells (MSCs) and their secretome have gained specific prominence in this regard. Additionally, technologies like tissue nano-transfection enable in situ gene editing, a need-specific approach without the requirement of complex laboratory procedures. Innovating approaches like 3D bioprinting and ECM bioscaffolds also hold the potential to address wounds at the molecular and cellular levels. These regenerative approaches target common healing obstacles, such as hyper-inflammation thereby promoting self-recovery through crucial signaling pathway stimulation. The rationale of this review is to examine the benefits and limitations of both current and emerging technologies in wound care and to offer insights into potential advancements in the field. The shift towards such patient-centric therapies reflects a paradigmatic change in wound care strategies.

Synergistic therapeutic approach for hemorrhoids: integrating mesenchymal stem cells with diosmin-hesperidin to target tissue edema and inflammation

Introduction

Mesenchymal stem cells (MSCs) have promising regenerative properties in tissue repair and anti-inflammatory responses. This study aimed to investigate the effects of MSCs and their combination with micronized purified flavonoid fraction (MPFF) in a croton oil-induced hemorrhoids model on tissue edema, inflammation, and underlying molecular mechanisms.

Material and methods

MSCs were isolated and characterized for their adherence, differentiation capacity, and immunophenotyping. Croton oil-induced hemorrhoid mouse models were established to assess tissue edema, inflammation, tumor necrosis factor (TNF-α) expression, transforming growth factor-β (TGF-β) expression, collagen ratio, and MMP-9 activity. The effects of MSCs and their combination with MPFF (diosmin-hesperidin) were evaluated through histological examinations, western blot analysis, and gelatin zymography.

Results

Characterization confirmed the MSCs' plastic adherence, osteogenic differentiation potential, and immunophenotype (positive for CD90 and CD29, negative for CD45 and CD31). Treatment with MSCs alone or in combination with MPFF significantly reduced tissue edema, inflammation, TNF-α expression, and MMP-9 activity. Additionally, MSCs increased TGF-β expression, and collagen type I/III ratio, and accelerated wound healing by resolving inflammation.

Conclusions

These findings suggest that MSCs play a crucial role in modulating TNF-α, TGF-β, collagen remodeling, and MMP-9 activity, highlighting their promising role in hemorrhoid treatment and wound healing processes. Further research is warranted to fully elucidate the intricate mechanisms and optimize MSC-based therapies for clinical applications in hemorrhoidal disease management.

Quercus glauca Acorn Seed Coat Extract Promotes Wound Re-Epithelialization by Facilitating Fibroblast Migration and Inhibiting Dermal Inflammation

The skin, recognized as the largest organ in the human body, serves a vital function in safeguarding against external threats. Severe damage to the skin can pose significant risks to human health. There is an urgent requirement for safe and effective therapies for wound healing. While phytotherapy has been widely utilized for various health conditions, the potential of Quercus glauca in promoting wound healing has not been thoroughly explored. Q. glauca is a cultivated crop known for its abundance of bioactive compounds. This study examined the wound-healing properties of Quercus glauca acorn seed coat water extract (QGASE). The findings from the study suggest that QGASE promotes wound closure in HF cells by upregulating essential markers related to the wound-healing process. Additionally, QGASE demonstrates antioxidant effects, mitigating oxidative stress and aiding in recovery from injuries induced by H2O2. In vivo experiments provide additional substantiation supporting the efficacy of QGASE in enhancing wound healing. The collective results indicate that QGASE may be a promising candidate for the development of innovative therapeutic strategies aimed at enhancing skin wound repair.

Teicoplanin-Decorated Reduced Graphene Oxide Incorporated Silk Protein Hybrid Hydrogel for Accelerating Infectious Diabetic Wound Healing and Preventing Diabetic Foot Osteomyelitis

Developing hybrid hydrogel dressings with anti-inflammatory, antioxidant, angiogenetic, and antibiofilm activities with higher bone tissue penetrability to accelerate diabetic wound healing and prevent diabetic foot osteomyelitis (DFO) is highly desirable in managing diabetic wounds. Herein, the glycopeptide teicoplanin is used for the first time as a green reductant to chemically reduce graphene oxide (GO). The resulting teicoplanin-decorated reduced graphene oxide (rGO) is incorporated into a mixture of silk proteins (SP) and crosslinked with genipin to yield a physicochemically crosslinked rGO-SP hybrid hydrogel. This hybrid hydrogel exhibits high porosity, self-healing, shear-induced thinning, increased cell proliferation and migration, and mechanical properties suitable for tissue engineering. Moreover, the hybrid hydrogel eradicates bacterial biofilms with a high penetrability index in agar and hydroxyapatite disks covered with biofilms, mimicking bone tissue. In vivo, the hybrid hydrogel accelerates the healing of noninfected wounds in a diabetic rat and infected wounds in a diabetic mouse by upregulating anti-inflammatory cytokines and downregulating matrix metalloproteinase-9, promoting M2 macrophage polarization and angiogenesis. The implantation of hybrid hydrogel into the infected site of mouse tibia improves bone regeneration. Hence, the rGO-SP hybrid hydrogel can be a promising wound dressing for treating infectious diabetic wounds, providing a further advantage in preventing DFO.

Icariin suppresses nephrotic syndrome by inhibiting pyroptosis and epithelial-to-mesenchymal transition

CONTEXT

Nephrotic syndrome(NS) has emerged as a worldwide public health problem. Renal fibrosis is the most common pathological change from NS to end-stage renal failure, seriously affecting the prognosis of renal disease. Although tremendous efforts have been made to treat NS, specific drug therapies to delay the progression of NS toward end-stage renal failure are limited. Epimedium is generally used to treat kidney disease in traditional Chinese medicine. Icariin is a principal active component of Epimedium.

METHODS

We used Sprague Dawley rats to establish NS models by injecting doxorubicin through the tail vein. Then icariin and prednisone were intragastric administration. Renal function was examined by an automatic biochemical analyzer. Pathology of the kidney was detected by Hematoxylin-Eosin and Masson staining respectively. Furthermore, RT-PCR, Enzyme-Linked Immunosorbent Assay, Immunohistochemistry, Western Blot and Terminal-deoxynucleotidyl Transferase Mediated Nick End Labeling staining were employed to detect the proteins related to pyroptosis and EMT. HK-2 cells exposed to doxorubicin were treated with icariin, and cell viability was assessed using the MTT. EMT was assessed using Enzyme-Linked Immunosorbent Assay and Western Blot.

RESULTS

The study showed that icariin significantly improved renal function and renal fibrosis in rats. In addition, icariin effectively decreased NOD-like receptor thermal protein domain associated protein 3,Caspase-1, Gasdermin D, Ly6C, and interleukin (IL)-1β. Notably, treatment with icariin also inhibited the levels of TGF-β, α-SMA and E-cadherin.

DISCUSSION AND CONCLUSIONS

It is confirmed that icariin can improve renal function and alleviate renal fibrosis by inhibiting pyroptosis and the mechanism may be related to epithelial-to-mesenchymal transition. Icariin treatment might be recommended as a new approach for NS.

Nisin-preconditioned mesenchymal stem cells combatting nosocomial Pseudomonas infections

Background

Nosocomial infections caused by multidrug-resistant Pseudomonas aeruginosa are a considerable public health threat, requiring innovative therapeutic approaches.

Objectives

This study explored preconditioning mesenchymal stem cells (MSCs) with the antimicrobial peptide Nisin to enhance their antibacterial properties while maintaining regenerative capacity.

Methods

Human MSCs were preconditioned with varying concentrations of Nisin (0.1-1000 IU/mL) to determine an optimal dose. MSCs preconditioned with Nisin were characterized using microscopy, flow cytometry, gene expression analysis, and functional assays. The effects of preconditioning on the viability, phenotype, differentiation capacity, antimicrobial peptide expression, and antibacterial activity of MSCs against Pseudomonas aeruginosa were tested in vitro. The therapeutic efficacy was evaluated by topically applying conditioned media from Nisin-preconditioned versus control MSCs to infected wounds in a rat model, assessing bacterial burden, healing, host response, and survival.

Results

An optimal Nisin dose of 500 IU/mL was identified, which increased MSC antibacterial gene expression and secretome activity without compromising viability or stemness. Nisin-preconditioned MSCs showed upregulated expression of LL37 and hepcidin. Conditioned media from Nisin-preconditioned MSCs exhibited about 4-fold more inhibition of P. aeruginosa growth compared to non-preconditioned MSCs. In the wound infection model, the secretome of Nisin-preconditioned MSCs suppressed bacterial load, accelerated wound closure, modulated inflammation, and improved survival compared to standard MSC treatments.

Conclusion

This study explores the effect of preconditioning MSCs with the antimicrobial peptide Nisin on enhancing their antibacterial properties while maintaining regenerative capacity. Secreted factors from Nisin-preconditioned MSCs have the potential to attenuate infections and promote healing in vivo. The approach holds translational promise for managing antibiotic-resistant infections and warrants further development. Preconditioned MSCs with Nisin may offer innovative, multifaceted therapies for combating nosocomial pathogens and promoting tissue regeneration.

Schiff Base-Based Hydrogel Embedded with In Situ Generated Silver Nanoparticles Capped by a Hyaluronic Acid-Diethylenetriamine Derivative for Wound Healing Application

In this study, hydrogels were produced using a Schiff base reaction between two hyaluronic acid derivatives: one containing aldehyde groups (HA-Ald) and the other holding a diethylenetriamine with terminal amino groups (HA-DETA). The DETA portion promotes the in situ growth, complexation, and stabilization of silver nanoparticles (AgNPs), eliminating the need for external reducing agents. The reaction between HA-DETA and HA-Ald leads to the formation of imine bonds, which results in dynamically pH-responsive cross-linking. While the DETA capping ability helped in embedding the AgNPs, the on/off pH environmental responsivity of the hydrogel allows for a controlled and on-demand release of the drug, mainly when bacterial infections cause pH variation of the wound bed. The injectable hydrogels resulted in being highly compatible in contact with blood red cells, fibroblasts, and keratinocytes and capable of having a proliferative effect on an in vitro wound scratch model. The pH-responsive hydrogels showed proper antibacterial activity againstPseudomonas aeruginosaandStaphylococcus aureus, common bacterial strains presented in wound infections. Finally, in vivo wound model studies demonstrated an overall speeding up in the wound healing rate and advanced wound conditions in the experimental group treated with the hydrogels compared to control samples.

Release of miR-29 Target Laminin C2 Improves Skin Repair

miRNAs are small noncoding RNAs that regulate mRNA targets in a cell-specific manner. miR-29 is expressed in murine and human skin, where it may regulate functions in skin repair. Cutaneous wound healing model in miR-29a/b1 gene knockout mice was used to identify miR-29 targets in the wound matrix, where angiogenesis and maturation of provisional granulation tissue was enhanced in response to genetic deletion of miR-29. Consistently, antisense-mediated inhibition of miR-29 promoted angiogenesis in vitro by autocrine and paracrine mechanisms. These processes are likely mediated by miR-29 target mRNAs released upon removal of miR-29 to improve cell-matrix adhesion. One of these, laminin (Lam)-c2 (also known as laminin γ2), was strongly up-regulated during skin repair in the wound matrix of knockout mice. Unexpectedly, Lamc2 was deposited in the basal membrane of endothelial cells in blood vessels forming in the granulation tissue of knockout mice. New blood vessels showed punctate interactions between Lamc2 and integrin α6 (Itga6) along the length of the proto-vessels, suggesting that greater levels of Lamc2 may contribute to the adhesion of endothelial cells, thus assisting angiogenesis within the wound. These findings may be of translational relevance, as LAMC2 was deposited at the leading edge in human wounds, where it formed a basal membrane for endothelial cells and assisted neovascularization. These results suggest a link between LAMC2, improved angiogenesis, and re-epithelialization.

Recent advances in drug delivery and targeting for the treatment of pancreatic cancer

Despite significant treatment efforts, pancreatic ductal adenocarcinoma (PDAC), the deadliest solid tumor, is still incurable in the preclinical stages due to multifacet stroma, dense desmoplasia, and immune regression. Additionally, tumor heterogeneity and metabolic changes are linked to low grade clinical translational outcomes, which has prompted the investigation of the mechanisms underlying chemoresistance and the creation of effective treatment approaches by selectively targeting genetic pathways. Since targeting upstream molecules in first-line oncogenic signaling pathways typically has little clinical impact, downstream signaling pathways have instead been targeted in both preclinical and clinical studies. In this review, we discuss how the complexity of various tumor microenvironment (TME) components and the oncogenic signaling pathways that they are connected to actively contribute to the development and spread of PDAC, as well as the ways that recent therapeutic approaches have been targeted to restore it. We also illustrate how many endogenous stimuli-responsive linker-based nanocarriers have recently been developed for the specific targeting of distinct oncogenes and their downstream signaling cascades as well as their ongoing clinical trials. We also discuss the present challenges, prospects, and difficulties in the development of first-line oncogene-targeting medicines for the treatment of pancreatic cancer patients.

Scarring Skin: Mechanisms and Therapies

Skin injury always results in fibrotic, non-functional scars in adults. Although multiple factors are well-known contributors to scar formation, the precise underlying mechanisms remain elusive. This review aims to elucidate the intricacies of the wound healing process, summarize the known factors driving skin cells in wounds toward a scarring fate, and particularly to discuss the impact of fibroblast heterogeneity on scar formation. To the end, we explore potential therapeutic interventions used in the treatment of scarring wounds.

Secretome of Hypoxia-Preconditioned Mesenchymal Stem Cells Promotes Liver Regeneration and Anti-Fibrotic Effect in Liver Fibrosis Animal Model

<b>Background and Objective:</b> Liver fibrosis (LF) is a most common pathological process characterized by the activation of hepatocytes leading to the accumulation of extracellular matrix (ECM). Hypoxia precondition treated in MSCs (H-MSCs) could enhance their immunomodulatory and regeneration capability, through expressing robust anti-inflammatory cytokines and growth factors, known as H-MSCs secretome (SH-MSCs) that are critical for the improvement of liver fibrosis. However, the study regarding the efficacy and mechanism of action of SH-MSCs in ameliorating liver fibrosis is still inconclusive. In this study, the therapeutic potential and underlying mechanism for SH-MSCs in the treatment of liver fibrosis were investigated. <b>Materials and Methods:</b> A rat model with liver fibrosis induced by CCl₄ was created and maintained for 8 weeks. The rats received intravenous doses of SH-MSCs and secretome derived from normoxia MSCs (SN-MSCs), filtered using a tangential flow filtration (TFF) system with different molecular weight cut-off categories, both at a dosage of 0.5 mL. The ELISA assay was employed to examine the cytokines and growth factors present in both SH-MSCs and SN-MSCs. On the ninth day, the rats were euthanized and liver tissues were collected for subsequent histological examination and analysis of mRNA expression. <b>Results:</b> The ELISA test revealed that SH-MSCs exhibited higher levels of VEGF, PDGF, bFGF, IL-10, TGF-β and IL-6 compared to SN-MSCs. <i>In vivo</i>, administration of SH-MSCs notably decreased mortality rates. It also demonstrated a reduction in liver fibrosis, collagen fiber areas, α-SMA positive staining and relative mRNA expression of TGF-β. Conversely, SN-MSCs also contributed to liver fibrosis improvement, although SH-MSCs demonstrated more favorable outcomes. <b>Conclusion:</b> Current findings suggested that SH-MSCs could improve CCl₄-induced liver fibrosis and decrease α-SMA and TGF-β expression.

Soy protein/β-chitin sponge-like scaffolds laden with human mesenchymal stromal cells from hair follicle or adipose tissue promote diabetic chronic wound healing

Chronic wounds are a worldwide problem that affect >40 million people every year. The constant inflammatory status accompanied by prolonged bacterial infections reduce patient's quality of life and life expectancy drastically. An important cell type involved in the wound healing process are mesenchymal stromal cells (MSCs) due to their long-term demonstrated immunomodulatory and pro-regenerative capacity. Thus, in this work, we leveraged and compared the therapeutic properties of MSCs derived from both adipose tissue and hair follicle, which we combined with sponge-like scaffolds (SLS) made of valorized soy protein and β-chitin. In this regard, the combination of these cells with biomaterials permitted us to obtain a multifunctional therapy that allowed high cell retention and growing rates while maintaining adequate cell-viability for several days. Furthermore, this combined therapy demonstrated to increase fibroblasts and keratinocytes migration, promote human umbilical vein endothelial cells angiogenesis and protect fibroblasts from highly proteolytic environments. Finally, this combined therapy demonstrated to be highly effective in reducing wound healing time in vivo with only one treatment change during all the experimental procedure, also promoting a more functional and native-like healed skin.

The effects of berberine on ischemia-reperfusion injuries in an experimental model of ovarian torsion

OBJECTIVE

Ovarian torsion is a gynecological disorder that causes ischemia-reperfusion injuries in the ovary. Our study investigated berberine's short- and long-term effects on ovarian ischemia-reperfusion injuries.

METHODS

This study included 28 Wistar albino female rats weighing 180 to 220 g, which were divided into four groups: sham (S), torsion/detorsion (T/D), torsion/ detorsion+single dose berberine (T/D+Bb), and torsion/detorsion+15 days berberine (T/D+15Bb). The torsion and detorsion model was applied in all non-sham groups. In the T/D+Bb group, a single dose of berberine was administered, while in the T/D+15Bb group, berberine was administered over a period of 15 days. After the rats were euthanized, their ovaries were excised. The left ovaries were used for histopathologic evaluation, which included ovarian injury scoring and follicle count, while the right ovaries were used for biochemical analyses (tissue transforming growth factor-β [TGF-β] and alpha-smooth muscle actin [α-SMA] levels).

RESULTS

The histopathologic evaluation scores for the ovaries were significantly lower in the T/D+B group (p<0.05) and the T/D+15B group (p<0.005) than in the T/D group. The follicle counts in the T/D group were lower than those in both the sham and treated groups (p<0.005). The TGF-β levels were significantly lower in the T/D+15B group (p<0.005), whereas the α-SMA levels did not show a significant difference.

CONCLUSION

Both short- and long-term berberine use could potentially have therapeutic effects on ovarian torsion. Long-term berberine use exhibited anti-inflammatory effects by reducing TGF-β levels, thereby preventing ischemia-reperfusion injuries. Therefore, we suggest that long-term berberine use could be beneficial for ovarian torsion.

A Comprehensive Review on Platelet-Rich Plasma Activation: A Key Player in Accelerating Skin Wound Healing

Platelet-rich plasma (PRP) activation is emerging as a promising and multifaceted tool for accelerating skin wound healing. This review extensively examines PRP's role in wound healing, focusing on its composition, mechanisms of action, activation methods, and clinical applications. PRP's potential to enhance both chronic and acute wound healing and its applications in cosmetic and aesthetic procedures are explored. Furthermore, this review investigates safety concerns, including adverse reactions, infection risks, and long-term safety implications. Looking to the future, emerging technologies, combination therapies, personalized medicine approaches, and regulatory developments are discussed, pointing towards an important and transformative era in wound healing and regenerative medicine. With its wide-ranging implications for healthcare, PRP activation has the potential to become a ubiquitous and essential therapeutic option, improving patient outcomes and reducing healthcare costs.

Mesenchymal Stem Cell Extracellular Vesicles from Tissue-Mimetic System Enhance Epidermal Regeneration via Formation of Migratory Cell Sheets

BACKGROUND

The secretome of adipose-derived mesenchymal stem cells (ASCs) offers a unique approach to understanding and treating wounds, including the critical process of epidermal regeneration orchestrated by keratinocytes. However, 2D culture techniques drastically alter the secretory dynamics of ASCs, which has led to ambiguity in understanding which secreted compounds (e.g., growth factors, exosomes, reactive oxygen species) may be driving epithelialization.

METHODS

A novel tissue-mimetic 3D hydrogel system was utilized to enhance the retainment of a more regenerative ASC phenotype and highlight the functional secretome differences between 2D and 3D. Subsequently, the ASC-secretome was stratified by molecular weight and the presence/absence of extracellular vesicles (EVs). The ASC-secretome fractions were then evaluated to assess for the capacity to augment specific keratinocyte activities.

RESULTS

Culture of ASCs within the tissue-mimetic system enhanced protein secretion ~ 50%, exclusively coming from the > 100 kDa fraction. The ASC-secretome ability to modulate epithelialization functions, including migration, proliferation, differentiation, and morphology, resided within the "> 100 kDa" fraction, with the 3D ASC-secretome providing the greatest improvement. 3D ASC EV secretion was enhanced two-fold and exhibited dose-dependent effects on epidermal regeneration. Notably, ASC-EVs induced morphological changes in keratinocytes reminiscent of native regeneration, including formation of stratified cell sheets. However, only 3D-EVs promoted collective cell sheet migration and an epithelial-to-mesenchymal-like transition in keratinocytes, whereas 2D-EVs contained an anti-migratory stimulus.

CONCLUSION

This study demonstrates how critical the culture environment is on influencing ASC-secretome regenerative capabilities. Additionally, the critical role of EVs in modulating epidermal regeneration is revealed and their translatability for future clinical therapies is discussed.

Role of alpha smooth muscle actin in odontogenic differentiation of dental pulp stem cells

Pulpotomy is an effective treatment for retaining vital pulp after pulp exposure caused by caries removal and/or trauma. The expression of alpha smooth muscle actin (α-SMA) is increased during the wound-healing process, and α-SMA-positive fibroblasts accelerate tissue repair. However, it remains largely unknown whether α-SMA-positive fibroblasts influence pulpal repair. In this study, we established an experimental rat pulpotomy model and found that the expression of α-SMA was increased in dental pulp after pulpotomy relative to that in normal dental pulp. In vitro results showed that the expression of α-SMA was increased during the induction of odontogenic differentiation in dental pulp stem cells (DPSCs) compared with untreated DPSCs. Moreover, α-SMA overexpression promoted the odontogenic differentiation of DPSCs via increasing mitochondrial function. Mechanistically, α-SMA overexpression activated the mammalian target of rapamycin (mTOR) signaling pathway. Inhibition of the mTOR signaling pathway by rapamycin decreased the mitochondrial function in α-SMA-overexpressing DPSCs and suppressed the odontogenic differentiation of DPSCs. Furthermore, we found that α-SMA overexpression increased the secretion of transforming growth factor beta-1 (TGF-β1). In sum, our present study demonstrates a novel mechanism by which α-SMA promotes odontogenic differentiation of DPSCs by increasing mitochondrial respiratory activity via the mTOR signaling pathway.

Secretome of Hypoxia-Preconditioned Mesenchymal Stem Cells Enhance Angiogenesis in Diabetic Rats with Peripheral Artery Disease

Background

Lower limb peripheral artery disease (PAD) is the main risk of diabetes mellitus which result to high mortality rate. Approximately, 50% of patients who receive several treatments have passed away or lost limbs at a year's follow-up. Secretome of hypoxia mesenchymal stem cells (S-MSCs) contains several active soluble molecules from hypoxia MSCs (H-MSCs) that capable inducing anti-inflammatory and vascular regeneration in PAD.

Objective

In this study, we investigated the therapeutic potential of S-MSCs in improving dynamic function and angiogenesis of PAD diabetic rats.

Methods

The PAD was established by the incision from the groin to the inner thigh and distal ligation of femoral arteries in rats with diabetes. Rats were administered with 200 µL and 400 µL S-MSCs that successfully filtrated using tangential flow filtration (TFF) system based on various molecular weight cut-off categories intravenously. ELISA assay was used to analyze the cytokines and growth factors contained in S-MSCs. Tarlov score were examined at day 1, 3, 5, 7, 10 and 14. The rats were sacrificed at day 14 and muscle tissues were collected for immunohistochemistry (IHC) and gene expression analysis.

Results

ELISA assay showed that S-MSCs provides abundant level of VEGF, PDGF, bFGF, IL-10 and TGFβ. In vivo administration of S-MSCs remarkably enhanced the Tarlov score. S-MSCs improved angiogenesis through enhancing VEGF gene expression and significantly increasing CD31 positive area in muscle tissue of PAD diabetic rats.

Conclusion

Our findings suggest that S-MSCs could improves dynamic function and angiogenesis in PAD diabetic rats.

Hyaluronic acid-g-lipoic acid granular gel for promoting diabetic wound healing

Diabetic patients are prone to developing chronic inflammation after trauma and have persistent nonhealing wounds. Reactive oxygen species (ROS) and recurrent bacterial infections at the site of long-term wounds also further delay skin wound healing and tissue regeneration. In this study, a granular gel (which exhibits ROS scavenging and antibacterial properties) is fabricated based on hyaluronic acid-g-lipoic acid (HA-LA). Briefly, HA-LA is synthesized to fabricate HA-LA microgels, which are further assembled by Ag+ via its coordination effect with disulfide in dithiolane to form a granular gel. The extrudable bulk granular gel possesses a shear-thinning feature and is immediately restored to a solid state after extrusion, and this can be easily applied to the whole wound area. Therefore, the grafted LA not only allows for the construction of the granular gel but also removes excess ROS from the microenvironment. Additionally, the presence of Ag+ realizes the assembly of microgels and has antibacterial effects. In vivo experiments show that the HA-LA granular gel eliminates excessive ROS at the wound site and up-regulates the secretion of reparative growth factors, thus, accelerating common and diabetic wound healing significantly. Therefore, the ROS-scavenging granular gel that can be applied to the wound surface with chronic inflammation demonstrates strong clinical utility.

The Fabrication of Gelatin-Elastin-Nanocellulose Composite Bioscaffold as a Potential Acellular Skin Substitute

Gelatin usage in scaffold fabrication is limited due to its lack of enzymatic and thermal resistance, as well as its mechanical weakness. Hence, gelatin requires crosslinking and reinforcement with other materials. This study aimed to fabricate and characterise composite scaffolds composed of gelatin, elastin, and cellulose nanocrystals (CNC) and crosslinked with genipin. The scaffolds were fabricated using the freeze-drying method. The composite scaffolds were composed of different concentrations of CNC, whereas scaffolds made of pure gelatin and a gelatin-elastin mixture served as controls. The physicochemical and mechanical properties of the scaffolds, and their cellular biocompatibility with human dermal fibroblasts (HDF), were evaluated. The composite scaffolds demonstrated higher porosity and swelling capacity and improved enzymatic resistance compared to the controls. Although the group with 0.5% (w/v) CNC recorded the highest pore size homogeneity, the diameters of most of the pores in the composite scaffolds ranged from 100 to 200 μm, which is sufficient for cell migration. Tensile strength analysis revealed that increasing the CNC concentration reduced the scaffolds' stiffness. Chemical analyses revealed that despite chemical and structural alterations, both elastin and CNC were integrated into the gelatin scaffold. HDF cultured on the scaffolds expressed collagen type I and α-SMA proteins, indicating the scaffolds' biocompatibility with HDF. Overall, the addition of elastin and CNC improved the properties of gelatin-based scaffolds. The composite scaffolds are promising candidates for an acellular skin substitute.

Effect of Secretome-Hypoxia Mesenchymal Stem Cells on Regulating SOD and MMP-1 mRNA Expressions in Skin Hyperpigmentation Rats

BACKGROUND: Ultraviolet B (UVB) radiation is the main factor causing hyperpigmentation. MSC secretome contains bioactive soluble molecules such as cytokines and growth factors that can accelerate skin regeneration. However, the molecular role of the secretome in hyperpigmentation is still unclear. AIM: This study aimed to determine the effect of secretome hypoxia mesenchymal stem cells (S-HMSC) gel on the expression of superoxide dismutase (SOD) and matrix metalloproteinases (MMP-1) genes in skin tissue of hyperpigmented rats induced by UVB light exposure. MATERIALS AND METHODS: Experimental research with post-test only control group. The control, base gel, T1 and T2 groups were UVB irradiated 6 times in 14 days at 302 nm with an minimal erythema dose of 390 mJ/cm2, respectively, while sham group did not receive UVB exposure. T1 was given 100 uL of S-HMSC gel and T2 was given 200 uL of S-HMSC gel every day for 14 days, while base gel received base gel. On day 15, skin tissue was isolated and analyzed for SOD and MMP-1 expression using qRT-PCR. RESULTS: The relative expression of the SOD gene in the treatment group (P1 = 0.47 ± 0.20, P2 = 1.22 ± 0.47) increased with increasing dose compared to the control group (UVB = 0.05 ± 0.01, Base gel = 0.05 ± 0.02). The relative expression of the MMP-1 gene in the treatment group (T1 = 5.82 ± 1.16, T2 = 2.86 ± 1.57) decreased with increasing dose compared to the control group (Control = 10.10 ± 2.31, and Base gel = 9.55 ± 1.29). CONCLUSION: Administration of S-HMSC gel can increase SOD gene expression and decrease MMP-1 gene expression in skin tissue of hyperpigmented rats model induced by UVB light.

Potential of stem cell seeded three-dimensional scaffold for regeneration of full-thickness skin wounds

Hypoxic wounds are tough to heal and are associated with chronicity, causing major healthcare burden. Available treatment options offer only limited success for accelerated and scarless healing. Traditional skin substitutes are widely used to improve wound healing, however, they lack proper vascularization. Mesenchymal stem cells (MSCs) offer improved wound healing; however, their poor retention, survival and adherence at the wound site negatively affect their therapeutic potential. The aim of this study is to enhance skin regeneration in a rat model of full-thickness dermal wound by transplanting genetically modified MSCs seeded on a three-dimensional collagen scaffold. Rat bone marrow MSCs were efficiently incorporated in the acellular collagen scaffold. Skin tissues with transplanted subcutaneous scaffolds were histologically analysed, while angiogenesis was assessed both at gene and protein levels. Our findings demonstrated that three-dimensional collagen scaffolds play a potential role in the survival and adherence of stem cells at the wound site, while modification of MSCs with jagged one gene provides a conducive environment for wound regeneration with improved proliferation, reduced inflammation and enhanced vasculogenesis. The results of this study represent an advanced targeted approach having the potential to be translated in clinical settings for targeted personalized therapy.

Fibroblast Growth Factor 7 Suppresses Fibrosis and Promotes Epithelialization during Wound Healing in Mouse Fetuses

Adult mammalian wounds leave visible scars, whereas skin wounds in developing mouse fetuses are scarless until a certain point in development when complete regeneration occurs, including the structure of the dermis and skin appendages. Analysis of the molecular mechanisms at this transition will provide clues for achieving scarless wound healing. The fibroblast growth factor (FGF) family is a key regulator of inflammation and fibrosis during wound healing. We aimed to determine the expression and role of FGF family members in fetal wound healing. ICR mouse fetuses were surgically wounded at embryonic day 13 (E13), E15, and E17. Expression of FGF family members and FGF receptor (FGFR) in tissue samples from these fetuses was evaluated using in situ hybridization and reverse transcription-quantitative polymerase chain reaction. Fgfr1 was downregulated in E15 and E17 wounds, and its ligand Fgf7 was upregulated in E13 and downregulated in E15 and E17. Recombinant FGF7 administration in E15 wounds suppressed fibrosis and promoted epithelialization at the wound site. Therefore, the expression level of Fgf7 may correlate with scar formation in late mouse embryos, and external administration of FGF7 may represent a therapeutic option to suppress fibrosis and reduce scarring.

Mesenchymal Stem Cell-Derived Exosomes Loaded with miR-155 Inhibitor Ameliorate Diabetic Wound Healing

Diabetic wounds are one of the debilitating complications that affect up to 20% of diabetic patients. Despite the advent of extensive therapies, the recovery rate is unsatisfactory, and approximately, 25% of patients undergo amputation, thereby demanding alternative therapeutic strategies. On the basis of the individual therapeutic roles of the miR-155 inhibitor and mesenchymal stem cells (MSC)-derived exosomes, we conjectured that the combination of the miR-155 inhibitor and MSC-derived exosomes would have synergy in diabetic wound healing. Herein, miR-155-inhibitor-loaded MSC-derived exosomes showed synergistic effects in keratinocyte migration, restoration of FGF-7 levels, and anti-inflammatory action, leading to accelerated wound healing mediated by negative regulation of miR-155, using an in vitro co-culture model and in vivo mouse model of the diabetic wound. Furthermore, treatment with miR-155-inhibitor-loaded MSC-derived exosomes led to enhanced collagen deposition, angiogenesis, and re-epithelialization in diabetic wounds. This study revealed the therapeutic potential of miR-155-inhibitor-loaded MSC-derived exosomes in diabetic wound healing and opened the doors for encapsulating miRNAs along with antibiotics within the MSC-derived exosomes toward improved management of chronic, nonhealing diabetic wounds.

Healing Mechanisms in Cutaneous Wounds: Tipping the Balance

Acute and chronic cutaneous wounds pose a significant health and economic burden. Cutaneous wound healing is a complex process that occurs in four distinct, yet overlapping, highly coordinated stages: hemostasis, inflammation, proliferation, and remodeling. Postnatal wound healing is reparative, which can lead to the formation of scar tissue. Regenerative wound healing occurs during fetal development and in restricted postnatal tissues. This process can restore the wound to an uninjured state by producing new skin cells from stem cell reservoirs, resulting in healing with minimal or no scarring. Focusing on the pathophysiology of acute burn wounds, this review highlights reparative and regenerative healing mechanisms (including the role of cells, signaling molecules, and the extracellular matrix) and discusses how components of regenerative healing are being used to drive the development of novel approaches and therapeutics aimed at improving clinical outcomes. Important components of regenerative healing, such as stem cells, growth factors, and decellularized dermal matrices, are all being evaluated to recapitulate more closely the natural regenerative healing process.

Melatonin pre-treated bone marrow derived-mesenchymal stem cells prompt wound healing in rat models

Bone marrow derived-mesenchymal stem cells (BMSCs)-based therapy is an outstanding candidate for cutaneous wound healing. Melatonin (MEL) has been reported for its anti-inflammatory as well as tissue regenerative properties. Existing work aimed to explore the potential healing power of BMSCs pre-treated with MEL in a skin wound model. Adult rats were allocated into control, PIO, BMSCs (1 × 105 cells), and MEL/BMSCs groups. On the 21 days post-wounding, tissues were sampled for analysis. The results demonstrated that compared to the control group, MEL/BMSCs therapy induced noticeable decline in wound area and elevated rate of wound retraction. Furthermore, marked increases in tissue hydroxyproline, as well as tissue content and gene expression level of vascular endothelial growth factor in MEL/BMSCs treated-wounded animals. Compared to the untreated control group, marked increases were found in antioxidant enzymatic activities together with elevated GSH levels in wounded tissues after MEL/BMSCs treatment. Moreover, therapeutically handled wounds with MEL/BMSCs revealed low levels of MDA, NO and protein carbonyls. Combined therapy with MEL/BMSCs relieved the inflammation witnessed by decreasing IL-1β, TNF-α and NF-κB levels in wounded tissues. Furthermore, noteworthy rises in levels of TGF-β and gene expression of α-SMA were noticed after MEL/BMSCs application that reveals their anti-scarring properties. Histologically, noticeable improvement in histopathological skin lesions in wound area and elevated the collagen synthesis and deposition. Collectively, the obtained data depict that the pre-treatment of BMSCs with MEL could potentially be a successful strategy for scaling-up the wound healing outcomes more than using BMSCs monotherapy in rat models.