Cutaneous Healing Research Articles

Evaluations of a Cutaneous Wound Healing Model Using Oxygen Enhanced - Dynamic Contrast Enhanced Photoacoustic Imaging (OE-DCE PAI).

Preclinical models of cutaneous wound healing can be useful for improving clinical wound care. Oxygen Enhanced Photoacoustic imaging (OE PAI) can measure oxygenation, and Dynamic Contrast Enhanced (DCE) PAI can measure vascular perfusion. We investigated how a combined OE-DCE PAI protocol can measure vascular oxygenation and perfusion to a cutaneous healing model. We developed a cutaneous "punch" wound model and photographed the wounds to track healing for 9 days. We performed OE-DCE PAI on Day 0, 3, 6, and 9. OE PAI was performed with 21% O2 and 100% O2 breathing gases to measure oxyhemoglobin (HbO2), deoxyhemoglobin (Hb), total hemoglobin (HbT), and oxygen saturation (%sO2), along with changes in these parameters caused by a change in breathing gas (ΔHb, ΔHbO2, ΔHbT, ΔsO2). To perform DCE PAI, indocyanine green (ICG) was administered intravenously while monitoring the PAI signal for 10min as the agent washed through the wound area, which was used to evaluate the wash-out rate. The average wound size was significantly smaller only by Day 6. For comparison, OE PAI measured a significant increase in HbO2, Hb, HbT, and %sO2 immediately after creating the wound, which significantly decreased by Day 3 and continued to decrease towards values for normal tissue by Day 9. The vascular wash-out rate significantly increased by Day 3, and continued to increase during the healing process. Notably, the wash-out rate can be assessed at a single PAI absorbance wavelength and by simply comparing signal amplitudes without advanced analysis, which may facilitate clinical translation. OE-DCE PAI can monitor significant changes in vascular perfusion and oxygenation prior to significant changes in cutaneous wound size. These results establish OE-DCE PAI as a tool for future pre-clinical wound healing studies and eventual clinical translation.

Tunicate cellulose nanocrystal reinforced multifunctional hydrogel with super flexible, fatigue resistant, antifouling and self-adhesive capability for effective wound healing

Hydrogels as skin wound dressings have been extensively studied owing to their good flexibility and biocompatibility. Nevertheless, the mechanical performance, adhesive capability, antifouling and antibacterial properties of conventional hydrogels are still unsatisfactory, which hinder the application of hydrogel for cutaneous healing. Here, we developed a novel biocompatible multifunctional hydrogel with super flexible, fatigue resistant, antifouling and self-adhesive capability for effective wound healing, where naturally rigid polymers including quaternized chitosan (QCS) and Tunicate cellulose nanocrystals (TCNCs) are used as bioactive cross-linkers and reinforcers to endow the hydrogel with excellent mechanical and antibacterial property, and the synergistic contributions from the poly(acrylic acid/methacrylate anhydride dopamine/sulfobetaine methacrylate) (poly(AA/DMA/SBMA)) chains and QCS endow the hydrogel with excellent adhesive property, antioxidant, antifouling and pH-responsive sustained drug release capabilities. The optimized hydrogel exhibited high tensile strength (77.69 KPa), large tensile strain (889.9 %), large toughness (307.51KJ.m−3), high adhesive strength (35.57 KPa) and ideal compressive property. The in vivo infected full-thickness skin model demonstrated that the hydrogel with vanvomycin sustained release ability efficiently improved the granulation tissue formation, facilitating collagen deposition and reducing inflammatory expression, thus effectively accelerating wound healing. This superiorly skin-adhesive antibacterial biocompatible hydrogel appears to be a promising candidate for wound therapy.

The use of bone wax versus dermal regeneration matrix for the reconstruction of scalp defects.

Secondary intention healing is an alternative to consider in large tumors or tumors located in areas of limited skin mobility, such as the scalp. To promote epithelialization, we can use Dermal Regeneration Matrix (DRM) or bone wax. This study aimed to compare the efficacy of DRM and bone wax in secondary intention healing of cutaneous scalp tumors in elderly patients with comorbidities. The medical records of 18 patients with cutaneous scalp tumor healing by secondary intention from February 2022 to April 2023 were analyzed for demographic variables, tumor and surgical characteristics, time from withdrawal of material to complete epithelialization, and need for subsequent surgical intervention. Bone wax was used in 6 patients and DRM in 12. The mean patient age was 84.3 years, and the mean tumor size was 2.7 cm. There were no significant differences in demographics or postoperative complications between the groups. The median time to complete epithelization was 84.5 (60.2-108.7) days in the bone wax group and 105.0 (91.0-126.0) days in the DRM group, with no significant differences (P = 0.15). Bone wax is a simple and economical material that can be used for secondary intention healing of scalp tumors in elderly patients with high surgical risk.

Efficiency of Therapeutic Laser for treatment of Chronic Non Healing Wounds in Cats

The study on wound healing has focused on similarities rather than on differences between species. Recent studies by authors have revealed significant differences between the cat and the dog with respect to cutaneous healing. These differences made us to reconsider wound care dogma of the feline species. Research has shown significant quantitative and qualitative differences in wound healing between cats and dogs and wound heals in the former more slowly. Since, Laser Therapy enhances the phases of wound healing, the present study was undertaken to access the efficiency of laser for chronic non healing in cats.

Improving Cutaneous Wound Healing in Diabetic Mice Using Naturally Derived Tissue-Engineered Biological Dressings Produced under Serum-Free Conditions.

Long-term diabetes often leads to chronic wounds refractory to treatment. Cell-based therapies are actively investigated to enhance cutaneous healing. Various cell types are available to produce biological dressings, such as adipose-derived stem/stromal cells (ASCs), an attractive cell source considering their abundancy, accessibility, and therapeutic secretome. In this study, we produced human ASC-based dressings under a serum-free culture system using the self-assembly approach of tissue engineering. The dressings were applied every 4 days to full-thickness 8-mm splinted skin wounds created on the back of polygenic diabetic NONcNZO10/LtJ mice and streptozotocin-induced diabetic K14-H2B-GFP mice. Global wound closure kinetics evaluated macroscopically showed accelerated wound closure in both murine models, especially for NONcNZO10/LtJ; the treated group reaching 98.7% ± 2.3% global closure compared to 76.4% ± 11.8% for the untreated group on day 20 (p=0.0002). Histological analyses revealed that treated wounds exhibited healed skin of better quality with a well-differentiated epidermis and a more organized, homogeneous, and 1.6-fold thicker granulation tissue. Neovascularization, assessed by CD31 labeling, was 2.5-fold higher for the NONcNZO10/LtJ treated wounds. We thus describe the beneficial impact on wound healing of biologically active ASC-based dressings produced under an entirely serum-free production system facilitating clinical translation.

Autologous blood products: Leucocyte and Platelets Rich Fibrin (L-PRF) and Platelets Rich Plasma (PRP) gel to promote cutaneous ulcer healing – a systematic review

ObjectiveTo summarise evidence on the effectiveness of Platelet-Rich Plasma (PRP) gel and Leucocyte and Platelet Rich Fibrin (L-PRF) gel as agents promoting ulcer healing compared with the standard wound dressing...

Simulated microgravity attenuates skin wound healing by inhibiting dermal fibroblast migration via F-actin/YAP signaling pathway.

Skin and its cell components continuously subject to extrinsic and intrinsic mechanical forces and are mechanical sensitive. Disturbed mechanical homeostasis may lead to changes in skin functions. Gravity is the integral mechanical force on the earth, however, how gravity contributes to the maintenance of skin function and how microgravity in space affects the wound healing are poorly understood. Here, using microgravity analogs, we show that simulated microgravity (SMG) inhibits the healing of cutaneous wound and the accumulation of dermal fibroblasts in the wound bed. In vitro, SMG inhibits the migration of human foreskin fibroblast cells (HFF-1), and decreases the F-actin polymerization and YAP (yes-associated protein) activity. The SMG-inhibited migration can be recovered by activating YAP or F-actin polymerization using lysophosphatidic acid (LPA) or jasplakinolide (Jasp), suggesting the involvement of F-actin/YAP signaling pathway in this process. In SMG rats, LPA treatment improves the cutaneous healing with increased dermal fibroblasts in the wound bed. Together, our results demonstrate that SMG attenuates the cutaneous wound healing by inhibiting dermal fibroblast migration, and propose the crucial role of F-actin/YAP mechano-transduction in the maintenance of skin homeostasis under normal gravity, and YAP as a possible therapeutic target for the skin care of astronauts in space.

Polyurethane-based nanofibrous mat containing porphyrin with photosensitivity and bactericidal properties can promote cutaneous tissue healing in rats

The regeneration of cutaneous tissue is one of the most challenging issues in human regenerative medicine. To date, several studies have been done to promote cutaneous tissue healing with minimum side effects. The healing potential of polyurethane (PU)/Poly (caprolactone)–poly (ethylene glycol)–poly (caprolactone) (PCEC)/chitosan (CS) (PCS) nanofibrous mat with cationic photosensitizer meso tetrakis (N-methyl pyridinium-4-yl) porphyrin tetratosylate salt (TMP) was examined. The CS tripolyphosphate nanoparticles (CSNPs) were prepared and loaded by TMP to provide an efficient drug release system (TMPNPs) for delivery of TMP to promote wound healing. In in vitro setting, parameters such as bactericidal effects, cytocompatibility, and hemolytic effects were examined. The healing potential of prepared nanofibrous mats was investigated in a rat model of full-thickness cutaneous injury. PCS/TMP/TMPNPs nanofibers can efficiently release porphyrin in the aqueous phase. The addition of TMPNPs and CS to the PU backbone increased the hydrophilicity, degradation, and reduced mechanical properties. The culture of human fetal foreskin fibroblasts (HFFF2) on PCS/TMP/TMPNPs scaffold led to an increased survival rate and morphological adaptation analyzed by MTT and SEM images. Irradiation with a red laser (635 nm, 3 J/cm2) for the 30 s reduced viability of S. aureus and E. Coli bacteria plated on PCS/TMP and PCS/TMP/TMPNPs nanofibrous mats compared to PU/PCEC (PC) and PU/PCEC/CS (PCS) groups, indicating prominent antibacterial effects of PCS/TMP and PCS/TMP/TMPNPs nanofibrous (p < 0.05). Data indicated that PCS/TMP/TMPNPs mat enhanced healing of the full-thickness excisional wound in a rat model by the reduction of inflammatory response and fibrotic changes compared to the PC, and PCS groups (p < 0.05). Immunofluorescence imaging indicated that levels of Desmoglein were increased in rats that received PCS/TMP/TMPNPs compared to the other groups. It is found that a PU-based nanofibrous mat is an appropriate scaffold to accelerate the healing of injured skin.Graphical abstract

A tetramethylpyrazine-loaded hyaluronic acid-based hydrogel modulates macrophage polarization for promoting wound recovery in diabetic mice

The failure of wound healing often causes lower limb disability and amputation of diabetic patients. Current strategies for diabetic wound management often fail to achieve the expected outcomes, and emerging alternatives are urgently needed. Recent advances in the identification of active compounds from traditional herbal medicines provide promising therapeutics for tissue repair and regeneration. In this study, the pro-healing effects of tetramethylpyrazine (TMP, a natural alkaloid found in Ligusticum chuanxiong Hort) for diabetic wounds were for the first time demonstrated. The cutaneous healing was mainly achieved by TMP-mediated macrophage polarization from pro-inflammatory to pro-healing phenotype. In addition, the topical administration of TMP was facilitated by the hyaluronic acid (HA) hydrogel for promoting the full-thickness wounds in the experimental diabetic mice. Consequently, TMP-loaded HA hydrogel (TMP-HA) profoundly accelerated the wound closure in comparison with TMP-loaded INTRASITE Gel (it is a commercial hydrogel), which was evident with the inflammation mitigation, the angiogenesis enhancement, and the collagen deposition. Our work reveals the macrophage-modulatory function of TMP for diabetic wound healing and demonstrates great potential of TMP-HA for clinical application.

Topical formulation containing chitosan-chamomile microparticles in cutaneous wound healing in rats

Objective: The aim of this research was to evaluate the efficacy of a topical formulation containing chitosan-chamomile microparticles in cutaneous healing in rats. Method: Male Wistar rats (n=57) were randomly distributed into three groups: treatment; vehicle; and control. Evaluations were performed on days 2, 7 and 14 after the surgical procedure using skin lesion photography, and histological and biochemical analyses. Results: The results showed that there was no difference in the healing index and in the histological analysis of the inflammatory infiltrate among groups. Fibrogenesis was more significant in the group treated with the test formulation at day 7, and angiogenesis was greater in the vehicle and chamomile groups at day 2. The quantification of hydroxyproline showed a higher amount of collagen in the group treated with chamomile, mainly at day 14, although the histological quantification of collagen showed no difference between the groups. Conclusion: From the results of this study, it can be concluded that the formulation, although it had no effect on the healing time, improved the quality of the cicatricial tissue formed with a greater quantity of fibroblasts and collagen.

Topical formulation containing chitosan-chamomile microparticles in cutaneous wound healing in rats

Objective: The aim of this research was to evaluate the efficacy of a topical formulation containing chitosan-chamomile microparticles in cutaneous healing in rats. Method: Male Wistar rats (n=57) were randomly distributed into three groups: treatment; vehicle; and control. Evaluations were performed on days 2, 7 and 14 after the surgical procedure using skin lesion photography, and histological and biochemical analyses. Results: The results showed that there was no difference in the healing index and in the histological analysis of the inflammatory infiltrate among groups. Fibrogenesis was more significant in the group treated with the test formulation at day 7, and angiogenesis was greater in the vehicle and chamomile groups at day 2. The quantification of hydroxyproline showed a higher amount of collagen in the group treated with chamomile, mainly at day 14, although the histological quantification of collagen showed no difference between the groups. Conclusion: From the results of this study, it can be concluded that the formulation, although it had no effect on the healing time, improved the quality of the cicatricial tissue formed with a greater quantity of fibroblasts and collagen.

Expression of PKM2 in wound keratinocytes is coupled to angiogenesis during skin repair in vivo and in HaCaT keratinocytes in vitro

An injured skin is rapidly restored in a manner of wound healing. We have previously shown that intact insulin signaling and glucose uptake are fundamental to proper wound closure. Consequently, under exacerbated inflammation, compromised insulin action and glucose uptake lead to impaired healing. However, in spite of the increased attention to cell metabolism during tissue regeneration, metabolic mediators that govern cellular and physiological processes throughout skin repair remained largely elusive. Through assessment of mRNA using real-time PCR and protein blot analysis, we report that healing of cutaneous wounds comprise a boosted expression of genes involved in glycolysis, oxidative phosphorylation, pentose phosphate shunt, and glutamine anaplerosis. We further focused on the functional role of pyruvate kinase M (PKM) isoenzymes that catalyze the final and rate-limiting step of glycolysis. Whereas the expression of the metabolic constitutively active Pkm1 isozyme remained almost unchanged, Pkm2 is augmented during the inflammatory phase of healing. The immunohistochemistry and RNA in situ hybridization analysis showed a confined Pkm2 expression to keratinocytes of the hyperproliferative epithelium and, to a lesser extent, infiltrating neutrophils and monocytes as well as later on in macrophages. Notably, the expression of Pkm2 in keratinocytes facing the wound bed side colocalized with VEGF expression. The in vitro knockdown of PKM2 in HaCaT keratinocytes using small interfering (si) RNA confirmed an acute role for PKM2 in facilitating the complete induction of VEGF mRNA and protein expression in keratinocytes; this function is mainly HIF-1α independent.Key messages• Wound healing involves activation of glycolysis, oxidative phosphorylation, pentos-phosphate shunt, and replenishment of tri-carboxylic acid (TCA) cycle through glutamine anaplerosis.• The pyruvate kinase M2 (PKM2) isoform is upregulated during the inflammatory phase of cutaneous healing, mainly in keratinocytes of hyperproliferative epithelia.• In vivo, the expression of VEGF in wound keratinocytes is colocalized with PKM2.• PKM2 is required for full induction of VEGF in HaCaT keratinocytes in vitro.

Evaluation the effect of use of different levels of mallow (Malva Sylvestris) derived extracts on cutaneous skin lesions healing in Simmental heifers

Evaluation the effect of use of different levels of mallow (Malva Sylvestris) derived extracts on cutaneous skin lesions healing in Simmental heifers

Mannosylated imiquimod-terbinafine co-loaded transethosomes for cutaneous leishmaniasis; assessment of its anti-leishmanial potential, in vivo safety and immune response modulation

Current treatment options for cutaneous leishmaniasis are associated with myriad limiting factors including low penetration, poor efficacy, and drug toxicities. Herein, we reported imiquimod and terbinafine co-loaded mannosylated transethosomes (IMQ-TER-MTES) with enhanced cutaneous retention, macrophage targeting, anti-leishmanial potential, and dermal immunomodulation. IMQ-TER-MTES were optimized using Design Expert® followed by their loading into chitosan gel. Moreover, the antileishmanial response against amastigotes-infected macrophages and Leishmania-infected BALB/c mice was evaluated. Finally, the safety and immunomodulation activity of IMQ-TER-MTES gel was performed using BALB/c mice. Optimized IMQ-TER-MTES showed nano-sized particles with low poly-dispersibility index (PDI) and high drug entrapment. Mannosylation has augmented macrophage targeting and the internalization capability of TES. IMQ-TER-MTES showed significantly reduced IC50 value (19.56 ± 3.62 μg/ml), higher selectivity index (29.24), and synergism against Leishmania major (L. major) amastigotes. In L. major infected BALB/c mice, the cutaneous lesion healing potential of IMQ-TER-MTES was also elevated with reduced lesion size (1.52 ± 0.43 mm). Superior safety of IMQ-TER-MTES was observed in BALB/c mice along with adequate stimulation of dermal immune cells, in contrast to the ALDARA®. Moreover, incremented Nuclear factor Kappa-β (NF-κβ) and nitric oxide (NO) biosynthesis were observed with IMQ-TER-MTES.

The Effect of an Autologous Protein-Based Topical Serum on Cutaneous Burns.

Burns are skin lesions that can be life-threatening. Platelet-rich plasma (PRP) is growing as an effective alternative for the management of burns. The objective of this study was to assess the use of a storable topical serum based on plasma rich in growth factors (PRGF) in promoting burn wound healing, called Endoret-Serum (ES). 3D skin models were used to assess thermal burn injury. Extracellular matrix remodeling, tissue damage, and metabolic activity of explants were analyzed, and a histomorphometric examination was carried out. Silver sulfadiazine cream (SC) was used as control ointment for burn management. Three patients suffering from skin burns were also treated with ES and clinically assessed. Endoret-Serum was based on an enriched platelet fraction with neutral pH and containing a high load of growth factors. Both ES and SC reduced tissue damage after burn, with ES being more effective. ES treatment maintained the metabolic activity of explants at a healthy level, and increased collagen and elastin deposition. Both treatments preserved the cutaneous connective tissue and induced newly synthesized matrix, with ES being more effective. Both treatments induced an intense collagenization, but ES showed better results as it restored the basal layer network with reduced signs of fibrosis. ES decreased the apoptotic cell number. Patients suffering from skin burns showed complete healing after ES treatment. Endoret-Serum might promote cutaneous healing and may be useful for accelerating the regeneration of skin burns. J Drugs Dermatol. 2022;21(12):1330-1339. doi:10.36849/JDD.6763.

614 Modulation of NK cell activation by calcium from alginate dressings in vitro

Early after skin wounds, innate immune cells, including natural killer (NK) cells, infiltrate the wound bed within the first 24 hours. The application of widely used calcium alginate dressings facilitates cutaneous healing by releasing Ca2+ ions into the exudate and locally enriching its level. Since Ca2+ ions have been identified as one of the main activators of NK functions, the effects of two alginate dressings, Algosteril® (Algo, pure Ca2+ alginate) and Biatain® Alginate (BIA, Ca2+ alginate with CMC), and CaCl2 solution were compared on NK cell cytotoxicity by analyzing K562 lysis and CD107a expression as well as on their IFN-γ and TNF-α production.

Accelerating cutaneous healing in a rodent model of type II diabetes utilizing non-invasive focused ultrasound targeted at the spleen.

Healing of wounds is delayed in Type 2 Diabetes Mellitus (T2DM), and new treatment approaches are urgently needed. Our earlier work showed that splenic pulsed focused ultrasound (pFUS) alters inflammatory cytokines in models of acute endotoxemia and pneumonia via modulation of the cholinergic anti-inflammatory pathway (CAP) (ref below). Based on these earlier results, we hypothesized that daily splenic exposure to pFUS during wound healing would accelerate closure rate via altered systemic cytokine titers. In this study, we applied non-invasive ultrasound directed to the spleen of a rodent model [Zucker Diabetic Sprague Dawley (ZDSD) rats] of T2DM with full thickness cutaneous excisional wounds in an attempt to accelerate wound healing via normalization of T2DM-driven aberrant cytokine expression. Daily (1x/day, Monday-Friday) pFUS pulses were targeted externally to the spleen area for 3 min over the course of 15 days. Wound diameter was measured daily, and levels of cytokines were evaluated in spleen and wound bed lysates. Non-invasive splenic pFUS accelerated wound closure by up to 4.5 days vs. sham controls. The time to heal in all treated groups was comparable to that of healthy rats from previously published studies (ref below), suggesting that the pFUS treatment restored a normal wound healing phenotype to the ZDSD rats. IL-6 was lower in stimulated spleen (-2.24 ± 0.81 Log2FC, p = 0.02) while L-selectin was higher in the wound bed of stimulated rodents (2.53 ± 0.72 Log2FC, p = 0.003). In summary, splenic pFUS accelerates healing in a T2DM rat model, demonstrating the potential of the method to provide a novel, non-invasive approach for wound care in diabetes.

Injectable Crosslinked Genipin Hybrid Gelatin-PVA Hydrogels for Future Use as Bioinks in Expediting Cutaneous Healing Capacity: Physicochemical Characterisation and Cytotoxicity Evaluation.

The irregular shape and depth of wounds could be the major hurdles in wound healing for the common three-dimensional foam, sheet, or film treatment design. The injectable hydrogel is a splendid alternate technique to enhance healing efficiency post-implantation via injectable or 3D-bioprinting technologies. The authentic combination of natural and synthetic polymers could potentially enhance the injectability and biocompatibility properties. Thus, the purpose of this study was to characterise a hybrid gelatin–PVA hydrogel crosslinked with genipin (GNP; natural crosslinker). In brief, gelatin (GE) and PVA were prepared in various concentrations (w/v): GE, GPVA3 (3% PVA), and GPVA5 (5% PVA), followed by a 0.1% (w/v) genipin (GNP) crosslink, to achieve polymerisation in three minutes. The physicochemical and biocompatibility properties were further evaluated. GPVA3_GNP and GPVA5_GNP with GNP demonstrated excellent physicochemical properties compared to GE_GNP and non-crosslinked hydrogels. GPVA5_GNP significantly displayed the optimum swelling ratio (621.1 ± 93.18%) and excellent hydrophilicity (38.51 ± 2.58°). In addition, GPVA5_GNP showed an optimum biodegradation rate (0.02 ± 0.005 mg/h) and the highest mechanical strength with the highest compression modulus (2.14 ± 0.06 MPa). In addition, the surface and cross-sectional view for scanning electron microscopy (SEM) displayed that all of the GPVA hydrogels have optimum average pore sizes (100–199 μm) with interconnected pores. There were no substantial changes in chemical analysis, including FTIR, XRD, and EDX, after PVA and GNP intervention. Furthermore, GPVA hydrogels influenced the cell biocompatibility, which successfully indicated >85% of cell viability. In conclusion, gelatin–PVA hydrogels crosslinked with GNP were proven to have excellent physicochemical, mechanical, and biocompatibility properties, as required for potential bioinks for chronic wound healing.

Deer Antler Reserve Mesenchyme Cell-Conditioned Medium Reduces the Destruction of Periodontitis in Mice.

Reserve mesenchyme cells (RMCs) are a type of antler stem cells (ASCs) that contribute to the rapid growth of deer antlers, the only known mammalian organ that can fully regenerate annually. Based on the prior evidence, ASC-conditioned medium could improve regenerative cutaneous healing in rats. The purpose of the study was to evaluate the therapeutic effects of RMC-conditioned medium (RMC-CM) on reducing the destruction in the mice periodontitis (PD) model and the underlying mechanisms. The lipopolysaccharide (LPS)-stimulated RAW264.7 cells were used in vitro to verify the effects of RMC-CM. The results revealed that RMC-CM could significantly reduce bone resorption and osteoclast activation, upregulate anti-inflammatory macrophages (M2) related interleukin (IL)-10 and CD206, and downregulate pro-inflammatory macrophages (M1) related tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthase in vivo. In vitro, RMC-CM could significantly promote LPS-stimulated RAW264.7 cells migration, reduce osteoclast differentiation, downregulate the expression of TNF-α, IL-6, and IL-1β, and upregulate the expression of IL-10 and arginase 1. According to the results, we concluded that RMC-CM could significantly reduce alveolar bone resorption and inhibit inflammation in gingival tissue by decreasing the activation of osteoclasts and inducing macrophage polarization toward the M2 phenotype. This study may serve as the experimental foundation for RMC-CM in the treatment of PD.

Enxerto omental livre sem microanastomose vascular na cicatrização de feridas cutâneas em coelhos

ABSTRACT This study aims to evaluate the influence of free omental graft without vascular microanastomosis (FOGWVA) on experimental skin healing in rabbits. Through celiotomy, a 9cm2 free omental fragment was collected in 36 rabbits, with subsequent production of a deep linear cutaneous wound in the dorsal midline measuring 3cm. In 18 animals from the omental group (OG), the omental fragment collected was fixed subcutaneously with six simple interrupted stitches using a 4-0 polyamide thread. In both treated and control (CG) groups, intradermal dermorrhaphy was performed with 4-0 polyamide thread. Experimental wounds were clinically evaluated every day. Each of the groups was divided into three subgroups of 6 animals each for histopathological evaluation on the 7th, 14th, and 28th days of postoperative. In the OG wounds, the increase in volume (omentum activation) stood out after the second postoperative day. Macroscopy showed an organic reaction to the graft on day 7, with a progressive reduction in addition to neovascularization towards the omental graft. The intense presence of mononuclear cells and collagen deposition on day 7 demonstrated an accelerated process of tissue remodeling and repair. The FOGWVA omental graft remained viable and positively influenced the cutaneous healing of the experimental wounds in rabbits.