Complete Re-epithelialization Research Articles

Effect of quercetin and its combination with cyclodextrin on the healing of burn wounds in laboratory rats

. The aim of this study was to evaluate the effects of quercetin (QC) and its complex with 2-hydroxypropyl-β-cyclodextrin (QECD) in healing burn related skin wounds in the rat model. Male Wistar rats were subjected to third-degree burn injury of skin in the interscapular area using a metal rod heated to 80 °C. The area of the skin which the burn was applied to was secured from the surroundings by the protective chamber. In order to estimate the efficacy of different treatment modalities the experiments were carried out in two stages. On first stage of the study, the group of animals (n = 21) was subjected to burn injury and the wound surface was not affected with additional procedures except the substances for treatment being applied. During the second stage of the study with another group of animals (n = 18) the removal of necrotic tissue was carried out over the period of 3 to 7 days. The progress of the wound healing was followed by performing morphometric analyses in order to determine complete re-epithelialization. The phagocytic index of neutrophils was determined in washouts from the wounds during the healing process. The animals used on the first stage of the study were sacrificed at day 21 of the experiment and those on the second stage at day 43 and the tissues were subjected to histological examination. The amounts of white blood cells and phagocytic index of neutrophils were calculated in blood samples followed by the measurements of metabolic activities of neutrophils. The removal of necrotic tissue has been found to promote better wound healing caused by thermal exposure. No reliable evidence has been obtained on QC or QECD abilities to significantly accelerate the burn wound epithelialization. The square of the secondary wound scab covered the damaged skin surface has been found to be decreased in the first group of animals on the 14th day followed by the exposure while the rate of wound epithelialization has been found to be increased in the second group of animals at the final stage of wound healing under the treatment with substances being investigated. As a result the ability of QE and QECD to normalize the white blood cell differential, phagocytic and metabolic activities of neutrophils recruited to a wound and neutrophil blood levels has been found.

Evidence-Based Review of Clinical Applications and Outcomes of Automated Epidermal Grafting

Commercialization of an automated epidermal harvesting device (CelluTome™, Kinetic Concepts Inc., San Antonio, TX) in the last 6 years has led to numerous publications describing a growing number of clinical applications. The current article reviews this literature while summarizing outcomes. A total of 20 published reports including 284 automated graft recipients have been published. Complete reepithelialization occurs in 50–92% of recipient sites, often within 4–18 weeks of graft placement. Donor sites heal without scarring within 1–2 weeks. Current evidence suggests efficacy in using an automated epidermal harvesting device for the wounds of patients with multiple comorbidities and failing previous treatments for their wounds, including vascular ulcers, diabetic ulcers, surgical wounds, complex wounds, acute traumatic wounds, pyoderma gangrenosum, and burns. Limited evidence also suggests efficacy of automated epidermal grafting for disorders of pigmentation. Better trials studying individual clinical applications of epidermal grafting are needed.

Efficacy of Amniotic Membrane Transplantation for the Treatment of Corneal Ulcers.

To evaluate the outcome of amniotic membrane transplantation (AMTX) as a treatment for corneal ulcers. Patients treated with AMTX for refractory corneal ulcers between 2012 and 2017 were evaluated in a retrospective analysis. Primary outcome measure was complete reepithelialization. A total of 149 patients were included (mean age 68 ± 18 years). The mean duration between ulcer onset and AMTX was 42 ± 46 days. The longest time between ulcer diagnosis and AMTX was found in bacterial ulcers and the shortest time to AMTX in eyes with trauma/chemical burns (mean 65 ± 15 days and 14 ± 4 days, respectively). In 70% of the patients, a single AMTX procedure was sufficient to achieve epithelial closure (21% <1 month, 40% within 1 -3 months, and 9% within 3-6 months). Treatment failure was observed in 30% of all patients, and most of them underwent further interventions. Highest closure rates were found in bacterial ulcers, herpetic ulcers, and neurotrophic ulcers (80%, 85%, and 93%, respectively), whereas the lowest reepithelialization rates were found in ulcers after corneal surgery and ulcers associated with rheumatic disease (52% and 57%, respectively). AMTX is a valuable treatment option to achieve corneal epithelial wound healing in cases refractory to conventional treatment. Success rates differ depending on the etiology of ulcer.

Magnetic cholecysto-duodenal anastomosis

Introduction There is a growing interest in minimally invasive endoscopic gallbladder drainage therapies. Unlike stenting, a technology based on magnetic compression could theoretically produce a durable drainage anastomosis without residual foreign material. This study aimed to evaluate the safety and technical feasibility of a cholecysto-duodenal magnetic compression anastomosis. Material and methods We performed a survival study of two Yorkshire pigs. Duodenal magnets were deployed endoscopically; reciprocal gallbladder magnets were placed laparoscopically, and the magnets were coupled. Pigs underwent serial endoscopy documenting magnet expulsion and evolution of cholecysto-duodenal anastomosis creation. Necropsies and histological evaluation were performed. Primary endpoints were technical success and safety. Secondary endpoints included anastomosis integrity, patency, and histologic characteristics. Results Magnets were successfully delivered and coupled. Patent, leak-free anastomoses formed by day 4. Magnets were expelled by day 10. All anastomoses were widely patent at one month (mean diameter 15 mm). Necropsy showed the absence of adhesions affecting the anastomosis. Histology showed complete re-epithelialization without inflammation or foreign body reaction. Conclusions Magnetic cholecysto-duodenal anastomosis for gallbladder drainage appears safe and feasible in the animal model. The anastomoses are patent, leak-free, and without inflammation from the presence of foreign material. Technical modifications for magnet delivery under endoscopic ultrasound (EUS) guidance are currently underway.

1395 Treatment of Vaginal Mesh Exposure with Platelet Rich Plasma and CO2 Laser

Study Objective To present our experience of treating vaginal mesh exposure with various modalities including Platelet Rich Plasma (PRP) and Co2 Laser Design Prospective cohort study Setting Patients referred to a gynecologist with a special interest in urogynaecology who worked at Adelaide, Sydney, and Geelong Patients or Participants 34 patients with symptomatic mesh exposure between 2009 and 2018 Interventions All patients were offered treatment with vaginal topical estrogen. Patients who continued to be symptomatic were treated with either PRP alone or surgical excision and PRP injection. These patients have been followed up on an annual basis since the time of treatment. Measurements and Main Results • 5 women declined topical estrogen due to personal or family history of Breast cancer ○ 4 patients received PRP and had complete re-epithelialization of the vaginal mucosa ○ 1 patient received combined PRP and laser • 29 Women used vaginal estrogen ○ 6 women responded to long-term (3-6 months) E2 treatment and needed no further treatment. ○ 9 were treated with laser and PRP alone ○ 14 women required surgery • 4 women did not respond to E2 treatment and did not wish to have surgery; they received PRP and had complete re-epithelialization of the vaginal mucosa. • 14 women underwent surgical excision and primary closure with PRP injection at the time ○ 10 had laser and PRP ○ 9 of the 14 women needed no further surgery after six months. • 3 women had repeat surgery for further mesh exposure. Conclusion The treatment of symptomatic vaginal mesh exposure might be complex in some cases. In recurrent cases, multi-modal treatment may be required. PRP and PRP autologous graft may benefit women whose mesh exposure is associated with severe atrophy or where large areas of vaginal epithelium need removal.

The effect of hyaluronic acid on the skin healing in rats

Purpose: The objective of this study was to examine the effect of topical hyaluronic acid (HA) treatment on wound healing in rats. Methods: Wistar rats were randomly selected and allocated into 2 groups, with six rats each, all of them submitted to skin lesions (open wound with 5mm diameter). Group 1 – rats treated with topical 0,9% saline application in skin wounds. Group 2 – rats treated with topical hyaluronic acid 0,4% on skin wounds once a day for 7 days. After anesthesia on the 7th postoperative day, a biopsy of the skin dorsal wound area was performed for histopathological examination. A classification system based on the degree of reepithelization, granulation tissue formation and collagen organization were used to relate the morphological differences in wound healing. Results: Rats from control group treated with saline solution, on day 7, presented a general impairment of healing process, marked by an incomplete reepithelization (score 2,67 ± 0,4), a persistent exudation, fibrin, reduced accumulation of granulation tissue (score 2,2 ± 0,5) and a slight collagen deposition (score 2,43 ± 0,5), compared with the HA group. On the other side, morphological differences were visible on the evolution of wound repair process in rats treated with HA with a significant reduction in fibrinous exudation, epidermal lining reconstitution by complete reepithelization (score 3,8 ± 0,6), an increased accumulation of granulation tissue at wound edge and bed (score 3,7 ± 1,1), moderate collagen deposition (3,8 ± 0,7). The respective differences between the groups were significant (p&lt;0,05). Conclusions: Based on these findings, we may conclude that HA treatment contributes to improve healing of open wounds.

Study the effect of erbium:YAG laser plus topical 5‐flurouracil in stable vitiligo resistant to NB‐UVB phototherapy

NB-UVB phototherapy is still an effective treatment in vitiligo but requires more than 1year for its completion. Topical 5-flurouracil could improve the proliferation and migration of melanocytes. Laser-assisted dermabrasion results in stimulation of the inactive melanocytes present at the outer root sheath of the lower portion of the hair follicle, which migrates upward until they reach the surface of the skin. To evaluate the effect of Er:YAG laser skin ablation followed by topical 5-flurouracil on the outcome of NB-UVB phototherapy as a short term technique in resistant and stable vitiligo. The current study included 40 patients suffering from bilateral stable vitiligo resistant to NB-UVB. For each patient, one side of the body subjected to 4months NB-UVB sessions (control side). While the other side of the body subjected to one session of Er:YAG laser ablation combined with topical 5% 5-flurouracil application under occlusion followed by NB-UVB sessions for 4months after complete re-epithelization. Outcomes were evaluated objectively based on standard digital photographs, histopathological examination, patient satisfaction, and adverse effects. There was a statistically significant improvement in the repigmentation in laser side compared with control side. Histopathological examination revealed expression of prominent melanin pigmentation, with marked expression for Melan-A in laser side, whereas these findings were negative in control side. Er:YAG laser ablation, followed by 5FU application before NB-UVB phototherapy for vitiligo, is a safe and tolerable technique that improves the outcome of short-term NB-UVB therapy and is expected to increase patient compliance.

Appraisal on the wound healing potential of Melaleuca alternifolia and Rosmarinus officinalis L. essential oil-loaded chitosan topical preparations.

The present study investigates the wound healing potential of three chitosan-based topical preparations loaded with either tea tree essential oil, rosemary essential oil or a mixture of both oils in vivo. Essential oils of M. alternifolia and R. officinalis were analyzed using GC/MS. Essential oil-loaded chitosan topical preparations were formulated. Wound healing potential was evaluated in vivo using an excision wound model in rats. GC/MS analysis of M. alternifolia and R. officinalis essential oils revealed richness in oxygenated monoterpenes, representing 51.06% and 69.61% of the total oil composition, respectively. Topical application of chitosan-based formulation loaded with a mixture of tea tree and rosemary oils resulted in a significant increase in wound contraction percentage compared to either group treated with individual essential oils and the untreated group. Histopathological examination revealed that topical application of tea tree and rosemary oil combination demonstrated complete re-epithelialization associated with activated hair follicles. The high percentage of oxygenated monoterpenes in both essential oils play an important role in the antioxidant and wound healing potential observed herein. Incorporation of tea tree and rosemary essential oils in chitosan-based preparations in appropriate combination could efficiently promote different stages of wound healing.

PFN1 and integrin-β1/mTOR axis involvement in cornea differentiation of fibroblast limbal stem cells.

Ex vivo limbal stem cell transplantation is the main therapeutic approach to address a complete and functional re‐epithelialization in corneal blindness, the second most common eye disorder. Although important key points were defined, the molecular mechanisms involved in the epithelial phenotype determination are unclear. Our previous studies have demonstrated the pluripotency and immune‐modulatory of fibroblast limbal stem cells (f‐LSCs), isolated from the corneal limbus. We defined a proteomic profile especially enriched in wound healing and cytoskeleton‐remodelling proteins, including Profilin‐1 (PFN1). In this study we postulate that pfn‐1 knock down promotes epithelial lineage by inhibiting the integrin‐β1(CD29)/mTOR pathway and subsequent NANOG down‐expression. We showed that it is possible modulate pfn1 expression levels by treating f‐LSCs with Resveratrol (RSV), a natural compound: pfn1 decline is accompanied with up‐regulation of the specific differentiation epithelial genes pax6 (paired‐box 6), sox17 (sex determining region Y‐box 17) and ΔNp63‐α (p63 splice variant), consistent with drop‐down of the principle stem gene levels. These results contribute to understand the molecular biology of corneal epithelium development and suggest that pfn1 is a potential molecular target for the treatment of corneal blindness based on epithelial cell dysfunction.

Use of oxidized regenerated cellulose (ORC)/collagen/silver-ORC dressings to help manage skin graft donor site wounds

Harvesting donor site explants for split-thickness skin grafting creates an iatrogenic wound that presents additional challenges to clinicians due to morbidities such as persistent bleeding, pain, infection, and delayed epithelialization. Although there have been several randomized controlled trials to compare wound dressing effectiveness, there is still a lack of standardization for donor site wound dressings.A retrospective comparison of 59 patients that underwent split-thickness skin graft reconstructions between January 2017 and September 2018 was performed. Donor sites of Group 1 patients (n = 29) were treated with a transparent film dressing and transitioned to petrolatum gauze dressings if exudate management became problematic; Group 2 patients (n = 30) were treated with oxidized regenerated cellulose/collagen/silver-oxidized regenerated cellulose (ORC/C/Ag-ORC) dressings. Evaluations of time to epithelialization, number of dressings required, signs of inflammation, and objective pain were compared between groups.Group 1 was comprised of 18 female and 11 male patients, whereas Group 2 was comprised of 14 females and 16 males. There were no significant differences between groups when comparing age, sex, comorbidities, or donor site size (area or depth). Patients in Group 2 had a significantly shorter time to complete re-epithelialization (P < .0001), fewer dressing changes (P < .0001), and less objective pain as measured by the need for opioid pain mediation (P < .0001) when compared to Group 1. The percentage of patients with signs of inflammation was also lower for Group 2, although this difference was not statistically significant (P = .0797).Although prospective, controlled studies are still needed, data from this study suggest that ORC/C/Ag-ORC dressings could become a more effective alternative for the management of donor site wounds, especially in patients with known risk factors for wound healing.

Electrospun chitosan/PVA/bioglass Nanofibrous membrane with spatially designed structure for accelerating chronic wound healing.

Cutaneous wounds, especially chronic wounds, remain clinical challenges, and this is partially due to the complex healing process composed of four overlapping but distinct stages including hemostasis, inflammation, proliferation and remodeling. Therefore, wound dressings with spatially designed structures which can temporally regulate certain bioactive components to function at specific healing stages might be able to accelerate the healing process. In this study, nanobioglass incorporated chitosan-PVA (polyvinyl alcohol) trilayer nanofibrous membrane (nBG-TFM) was fabricated via sequential electrospinning. This membrane exhibited excellent biocompatibility, antibacterial activity and regeneration promotion effect. Furthermore, spatially designed structure optimized functions of each component and provided more suitable microenvironment as compared with uniform membrane. Rat full-thickness skin defects model and mice diabetic chronic wound model showed that nBG-TFM could achieve significantly accelerated and enhanced healing, in terms of complete re-epithelialization, improved collagen alignment and formation of skin appendages. It was revealed that nBG-TFM functioned through upregulating growth factors including VEGF and TGF-β. Meanwhile inflammatory cytokines such as TNF-α and IL-1β were downregulated. The technology presented in this study shed new light on designing functional wound dressings which can promote healing of chronic wounds.

Cuprous oxide nanoparticles reduces hypertrophic scarring by inducing fibroblast apoptosis.

BackgroundLess apoptosis and excessive growth of fibroblasts contribute to the progression of hypertrophic scar formation. Cuprous oxide nanoparticles (CONPs) could have not only inhibited tumor by inducing apoptosis and inhibiting proliferation of tumor cells, but also promoted wound healing. The objective of this study was to further explore the therapeutic effects of CONPs on hypertrophic scar formation in vivo and in vitro.MethodsIn vivo, a rabbit ear scar model was established on New Zealand albino rabbits. Six full-thickness and circular wounds (10 mm diameter) were made to each ear. Following complete re-epithelization observed on postoperative day 14, an intralesional injection of CONPs or 5% glucose solution was conducted to the wounds. The photo and ultrasonography of each wound were taken every week and scars were harvested on day 35 for further histomorphometric analysis. In vitro, the role of CONPs in human hypertrophic scar fibroblasts (HSFs) apoptosis and proliferation were evaluated by Tunnel assay, Annexin V/PI staining, cell cycle analysis, and EdU proliferation assay. The endocytosis of CONPs by fibroblasts were detected through transmission electron microscopy (TEM) and the mitochondrial membrane potential and ROS production were also detected.ResultsIn vivo, intralesional injections of CONPs could significantly improve the scar appearance and collagen arrangement, and decreased scar elevation index (SEI). In vitro, CONPs could prominently inhibit proliferation and induce apoptosis in HSFs in a concentration-dependent manner. In addition, CONPs could be endocytosed into mitochondria，damage the mitochondrial membrane potential and increase ROS production.ConclusionCONPs possessed the therapeutic potential in the treatment of hypertrophic scar by inhibiting HSFs proliferation and inducing HSFs apoptosis.

1748-P: Brucine Topical Administration Promotes Wound Healing through Downregulation of Proinflammatory Markers and Chemokine Expressions in Alloxan-Induced Diabetic Mice

Diabetes mellitus is a complex metabolic disease and delayed wound healing constitutes one of the most serious diabetes-associated complications. Diabetes can impede the wound healing process by inducing inflammation which can lead to delayed maturation of granulation tissues and reduced wound parallel tension. Brucine, one of the major constituents in Strychnos nux-vomica has antioxidant and anti-inflammatory properties. In this study, we investigated the effects of topical administration of brucine on the key mediators of wound healing, namely T cell subsets, glucocorticoid-induced tumor necrosis factor receptor expressing cells, CD4+CD25+Foxp3+ regulatory T (Treg) cells, Th17 cells, Th1 cytokines, and inflammatory mediator mRNA expression.In current study, 5 groups of mice were used (10/group): group 1, the nondiabetic normal control; group 2, wound in nondiabetic mice; group 3, wound in diabetic mice; group 4, brucine 20mg/kg treated wounds in diabetic mice. Wound size was recorded on every third day and after 14 days of treatment, the heparinized whole blood and the wound tissue of all the groups was collected and tested. Brucine administration showed a significant reduction in wound size, the levels of GITR-expressing cells, and Th1 cytokines as well as substantial down regulation of mRNA expression of the inflammatory mediators compared with the diabetic mice. Brucine also significantly up regulated the number of Tregs or also induced Th17/Treg balance and modulated various pro-inflammatory and anti-inflammatory cytokines and the mRNA expression of their mediators. Furthermore, histopathological examination showed complete re-epithelization, decreased inflammatory cells and presence of granulation tissue in the brucine treated mice. Therefore, our results suggest the beneficial effect of brucine in enhanced wound healing and rebalancing the wound environment in diabetes. Disclosure H. Madkhali: None. M. Ganaie: None. M.N. Ansari: None.

Preliminary design of a new degradable medical device to prevent the formation and recurrence of intrauterine adhesions

Intrauterine adhesions lead to partial or complete obliteration of the uterine cavity and have life-changing consequences for women. The leading cause of adhesions is believed to be loss of stroma resulting from trauma to the endometrium after surgery. Adhesions are formed when lost stroma is replaced by fibrous tissue that join the uterine walls. Few effective intrauterine anti-adhesion barriers for gynecological surgery exist. We designed a degradable anti-adhesion medical device prototype to prevent adhesion formation and recurrence and restore uterine morphology. We focused on ideal degradation time for complete uterine re-epithelialization for optimal anti-adhesion effect and clinical usability. We developed a triblock copolymer prototype [poly(lactide) combined with high molecular mass poly(ethylene oxide)]. Comparative pre-clinical studies demonstrated in vivo anti-adhesion efficacy. Ease of introduction and optimal deployment in a human uterus confirmed clinical usability. This article provides preliminary data to develop an intrauterine medical device and conduct a clinical trial.

Hyaluronic Acid Accelerates Re-epithelialization and Alters Protein Expression in a Human Wound Model.

Hyaluronic acid (HA), a large glycosaminoglycan involved in proliferation, migration, and tissue repair, is suggested to be an important factor for keratinocyte activation and re-epithelialization. The experimental hypothesis of this study was that HA accelerates re-epithelialization, and we aimed to investigate the effect of exogenous intradermal HA during deep dermal, incisional wound healing in vivo in humans, the primary endpoint being re-epithelialization. A total of 8 standardized deep dermal incisional wounds (depth 1.6 mm, width 1.8 mm) per subject were induced in 10 healthy volunteers. Two of the wound sites per subject were pretreated with injections of HA and 2 with saline solution. At 2 time points (24 hours and 14 days), 2 biopsies for each treatment group (one for histology and one for proteomics) were taken. Skin erythema was measured at 24-hour intervals for 14 days as a surrogate measurement of inflammation. At 24 hours, 8 of 9 wounds pretreated with HA showed complete re-epithelization, whereas none of the wounds pretreated with saline had re-epithelized. Wounds pretreated with HA also showed a 10-fold regulation of 8 identified proteins involved in wound healing compared to wounds treated with saline solution. No difference in inflammation, as measured as erythema, could be seen between any of the groups. We conclude that HA accelerates re-epithelialization and stimulates an altered protein expression in vivo in human deep dermal incisional skin wounds, but has no effect on the inflammation process as measured by erythema.

Glycyrrhizinate Dipotassium (DPG) Effects over Skin Wound Healing

Skin wound healing is a complex process involving cellular, and molecular events: inflammatory, proliferative, and remodeling phases. Infectious disease, pre‐existing diseases, medications, and aging can negatively interfere in healing. Research on leptin, collagenase, and tretinoin have been done attempting to promote healing. Glycyrrhizinate Dipotassium (DPG), derived from licorice, has anti‐allergic, antibiotic, and anti‐inflammatory effects, besides promoting the skeletal muscle regeneration by activating quiescent satellite cells, leading myoblasts and myotubes differentiation, and forming new muscle fibers. Considering these aspects, we purpose to verify the 2% DPG pharmacological effect on secondary intention wound healing in adult and aged animals. Twenty male Wistar rats were used. Two skins' excisions (2 cm diameter) of normal skin were made in the animal dorsal region (Naïve group). Topical application of 2% DPG was done on the distal wound daily for 7 days (Treated group). The proximal wound was not treated (Control group). After 14 or 21 days (n = 5 each) of wound creation, the samples were excised, fixed in 10% formol, and processed for paraffin inclusion. Slides were stained with hematoxylin and eosin (H&amp;E), and Masson's trichrome (MT) for histological analysis. Wound healing areas, epidermal and dermal measurements were performed. Statistical analysis adopted a 5% coefficient for null hypothesis rejection. Histological analysis revealed intact skins for Naïve group. Control and Treated groups presented skin with epidermis and dermis reshaped: all epidermal layers (basale, spinosum, granulosum, lucidum, and corneum stratum), as papillary and reticular dermis. In aged rats, the wound was smaller in treated than in untreated animals, resulting in a larger scar compared with the adult rats. However, when treated wounds were compared, no differences were found between the wound areas in adult and aged rats. After 14 days the epidermis thickness of adult and aged animals treated with DPG was thicker than untreated animals. However, after 21 days, the adult epidermis thickness of animals treated with DPG was thinner than untreated animals. The dermis thickness of adult and aged animals treated or non‐treated with 2% DPG did not differ. On the 21st day, adult and aged complete reepithelialization were found in treated animals. Results indicate that 2% DPG significantly reverses wounds process to a skin normal state, even for aged animals, by reepithelization, probably acting during inflammatory and proliferative phases of healing. Such results point DPG as a promissory agent to promote skin healing.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Nanocrystalline cellulose–hyaluronic acid composite enriched with GM-CSF loaded chitosan nanoparticles for enhanced wound healing

In recent years, applications of biopolymers such as hyaluronic acid (HA) for wound dressing have attracted more attention. However, the poor mechanical properties of HA-based wound dressings limit their clinical applications. Incorporation of reinforcing agents such as nanocrystalline cellulose (CNC) in HA-based wound dressings can improve their mechanical properties. In addition, controlled delivery of growth factors to the wound site using nanoparticles can significantly improve the healing process. In this study, we focus on development and characterization of a novel CNC reinforced HA-based composite containing chitosan nanoparticles loaded with GM-CSF (CNC-HA/GM-CSF-Chi-NPs composite) as an effective wound dressing. CNC-HA/GM-CSF-Chi-NPs composite showed some physicochemical characteristics such as appropriate mechanical properties, high swelling capacity (swelling ratio: 2622.1% ± 35.2%) and controlled release of GM-CSF up to 48 h which make it an excellent candidate for wound dressing. In vivo investigation showed that, after 13 d, the wounds covered with CNC-HA/GM-CSF-Chi-NPs composite could reach to nearly full wound closure and complete re-epithelialization compared to the normal saline treated wounds which exhibited nearly 70% of wound size reduction. Furthermore, the CNC-HA/GM-CSF-Chi-NPs composite treated wounds exhibited significantly lower inflammatory reaction, enhanced re-epithelialization and improved granulation tissue formation compared with CNC-HA/Chi-NPs composite treated wound; it might be due to positive effects of GM-CSF on the wound healing process. Our results suggest that CNC-HA/GM-CSF-Chi-NPs composite can be potentially applied in clinical practice for wound treatment.

The Effect of Using Bone Marrow Mesenchymal Stem Cells Versus Platelet Rich Plasma on the Healing of Induced Oral Ulcer in Albino Rats.

Background and ObjectivesOral ulceration is one of the most common debilitating condition that affects the oral cavity. In this study, the effect of locally injected platelet rich plasma (PRP) and bone marrow-derived mesenchymal stem cells (BMSCs) on the healing of oral ulcer was investigated.Methods and ResultsAn ulcer was induced in buccal mucosa of rats by using 5mm biopsy punch followed by application of cotton swab soaked with formocresol for 60sec. The ulcer was left untreated in the control group, treated with intralesional injection of PRP, or isolated cultured BMSCs. Data were analyzed clinically, histologically and immunohistologically on day 3, 5, 7 and 10. BMSCs group showed smaller ulcer area throughout the whole experimental period than the other groups with complete resolution of the ulcer on day 10, unlike the control group. However, there was no significant difference with PRP, on day 5, 7 and 10, regarding clinical ulcer size. BMSCs group showed better histological results regarding the rate of epithelial cell migration, the number of inflammatory cells, thickness and organization of collagen fibres and the number of blood vessels, with complete re-epithelization on day 10. BMSCs group showed a greater number of anti-PCNA positive nuclei throughout the whole experimental period than the other groups except on day 5, PRP had higher mean numbers of anti-PCNA positive nuclei in both tissues.ConclusionsBoth PRP and BMSCs accelerate wound healing and enhance the quality of the healing tissue with the latter being slightly more effective and faster.

Observation and mechanism study of bladder wound healing after transurethral holmium laser resection of bladder tumor.

This research aims to observe and compare the wound healing process of urethral bladder after transurethral holmium laser resection of bladder tumor (HoLRBT) and transurethral resection of bladder tumor (TURBT) and explore the possible mechanism of wound healing and bladder re-epithelialization after HoLRBT. An animal model of canine achieving HoLRBT and TURBT was established. Cystoscopy was performed at different time points (3days and 1, 2, 3, and 4weeks) after operation to observe the wound healing and re-epithelialization of bladder epithelium. Bladder mucosa specimens were obtained and histopathological changes of the bladder epithelium were observed under light microscope after HE staining. Immunochemistry was used to determine the cell expression ofCK5, CK14, EGF, EGFR; microRNA expressions of CK5, CK14, EGF, and EGFR were measured by qRT-PCR. The changes of urinary EGF concentration were detected by ELISA. The bladder epithelial wound was repaired and re-epithelialized at 1week after HoLRBT. At the 4th week, the bladder wound was basically completed and re-epithelialized; repair of bladder epithelial wounds recapitulates the wounds with the proliferation and migration of residual epithelial cells under the wound and the bladder epithelium that proliferates alongside the wound surface to complete re-epithelialization. The process begins at 1week after surgery and basically completes at 4weeks after surgery. CK5 and CK14 positive cells were detected in the basal cells of the bladder epithelium after HoLRBT, and the expression of CK5 and CK14 mRNA in the basal cells of the bladder epithelium under hyperplasia was significantly higher than that of the normal bladder epithelial basal cells. Bladder epithelial wound repair of TURBT group was performed by the proliferative differentiation of the peri-bladder epithelium adjacent to the wound edge and crawled to the wound surface to complete the re-epithelialization process. The wound repair and re-epithelialization were significantly slower than HoLRBT group. The CK5 and CK14 positive cells can also be detected in the basal cells of marginal hyperplasia of basal margin, and the expression of CK5 and CK14 mRNA in the basal cells of the peri-bladder hyperplasia is obviously higher than that of the normal bladder epithelial basal cells. The expression of EGF in bladder regenerating epithelium gradually increased with time after HoLRBT. Bladder basal cells and bladder regenerating epithelium express high levels of EGFR after HoLRBT. The concentration of EGF in urine after HoLRBT and TURBT increased significantly after surgery, and peaked at 3days after operation. The urinary EGF concentration in HoLRBT group was higher than that in TURBT group at 3 and 4weeks after operation. The re-epithelialization process can be seen 1week after the cystectomy with holmium laser cystectomy, and the epithelialization rate is faster than the traditional transection surgery. This is because the residual bladder epithelial stem cells and wound marginal epithelial cells are involved in the process of wound repair and re-epithelialization following HoLRBT. But only the marginal epithelial tissue participates in the re-epithelialization process after TURBT, so the repair rate of TURBT is slower. The repair of bladder epithelium after HoLRBT is related to the stimulation of tissue factor EGF. The regenerated bladder epithelium also participates in the wound repair process by means of autocrine of EGF.

Sida cordifolia accelerates wound healing process delayed by dexamethasone in rats: Effect on ROS and probable mechanism of action

Ethno pharmacological relevanceSida cordifolia is used commonly in traditional systems of medicine (TSM) and as folk remedies for treating the wounds (both external and internal), infected area, rheumatic disorders, muscular weakness, tuberculosis, heart problems, bronchitis, neurological problems etc. Therefore, in order to authenticate the claims, a mechanism-oriented investigation of the wound healing properties of this plant is essential. Aim of the study: The overall aim of the present research is to understand the precise unknown cellular and molecular mechanism by which S. cordifolia accelerates wound healing delay caused by the steroidal drug dexamethasone. Here, we have also tried to quantify intracellular superoxide with the help of a unique fluoroprobe MitoSOX based on fluorescence measurements in yeast Materials and methodsWound healing property of successive extracts (ethyl acetate, methanol and aqueous) of S. cordifolia against dexamethasone-induced retardation of wound healing in rats was studied. The various extracts of S. cordifolia were characterised by determining the various phytochemicals and quantifying the total phenolic content and flavonoidal content by High throughput assays. In order to know the probable mechanism of action of the successive fractionates, assessed the antioxidant activity both by in-vitro (DPPH-assay) and in-vivo methods in wild-type Saccharomyces cerevisiae BY 4743 (WT) and knock-out strain (Δtrx2) against H2O2-induced stress mediated damages. The cell survival was evaluated after exposure to the oxidizing reagent (4 mM H2O2) by two methods which included the ability of cells to proliferate on solid or liquid medium. The cell membrane integrity/amount of mitochondrial ROS was determined by treating the strains with extract/standard in presence of H2O2 and propidium iodide (PI)/MitoSOX Red ResultsDuring the preliminary in-vivo wound healing study, the period for complete re-epithelialization of the wound tissue was reduced significantly (pin the treatment groups as compared to the negative control group. The formulation HF3 containing aqueous extract of S. cordifolia (SCA) showed highest wound healing potential against dexamethasone-retarded wounds in rats which justifies its traditional use. In the growth curve assay, the H2O2-induced growth arrest was restored by aqueous extract of S. cordifolia (SCA) in a concentration-dependent(pmanner both in the WT and Δtrx2 strains similar to the standard (ascorbic acid), H2O2 after 24 hours incubation which was also confirmed by the findings of CFU method. We got almost similar results of cell viability when stained with PI. The lower level of mitochondrial superoxide was indicated by a significant (preduction in the amount of MitoSOX stained cells, in the extract-treated group in contrast to the H2O2-stressed group. ConclusionIt was concluded that HF3 can be applied topically in hydrogel form in the case of delayed wound healing caused by the steroidal drug-dexamethasone, aptly justifying its traditional use. Regarding its mechanism of action, our findings report that the potent adaptive response of SCA-treated WT and Δtrx2 strains towards intracellular ROS specifically mitochondrial-ROS confirms its antioxidant potential. Moreover, as SCA was able to rescue the Δtrx2 strains from stress, it can be inferred that it might be able to induce the enzyme thioredoxin-II to restore redox homeostasis. The findings with the conditional mutant ∆trx2 are the first proof linking SCA action related to particular cellular pathways which may be because of the phenols and flavonoids and their synergistic effect.