Combined therapy of photobiomodulation and adipose-derived stem cells synergistically improve healing in an ischemic, infected and delayed healing wound model in rats with type 1 diabetes mellitus

Tailoring photobiomodulation to enhance tissue regeneration

Photobiomodulation (PBM), the use of biocompatible tissue-penetrating light to interact with intracellular chromophores to modulate the fates of cells and tissues, has emerged as a promising non-invasive approach to enhancing tissue regeneration. Unlike photodynamic or photothermal therapies that require the use of photothermal agents or photosensitizers, PBM treatment does not need external agents. With its non-harmful nature, PBM has demonstrated efficacy in enhancing molecular secretions and cellular functions relevant to tissue regeneration. The utilization of low-level light from various sources in PBM targets cytochrome c oxidase, leading to increased synthesis of adenosine triphosphate, induction of growth factor secretion, activation of signaling pathways, and promotion of direct or indirect gene expression. When integrated with stem cell populations, bioactive molecules or nanoparticles, or biomaterial scaffolds, PBM proves effective in significantly improving tissue regeneration. This review consolidates findings from in vitro, in vivo, and human clinical outcomes of both PBM alone and PBM-combined therapies in tissue regeneration applications. It encompasses the background of PBM invention, optimization of PBM parameters (such as wavelength, irradiation, and exposure time), and understanding of the mechanisms for PBM to enhance tissue regeneration. The comprehensive exploration concludes with insights into future directions and perspectives for the tissue regeneration applications of PBM.

Experimental study on the effects of human amniotic membrane in combination with menstrual blood-derived stem cells on wound healing in a diabetic rat model

One of the serious challenges in diabetic patients is the occurrence of complications caused by the disease. One of the most important side effects is wounding in limbs. Due to the multifactorial nature of these wounds, treatments require a multifaceted approach. Therefore, the aim of the present study was whether the human amniotic membrane (HAM) in combination with menstrual blood-derived stem cells (MenSCs) could promote wound healing in diabetic rats. Thirty days after induction of diabetes, the animals were randomly allocated into four equal groups (n=15): the control group, HAM group, MenSC group, and HAM+MenSC group. Sampling was done on days 7, 14, and 21 for histological, molecular, and tensiometrical evaluations. The results showed that the wound healing rate, collagen deposition, volumes of new epidermis and dermis, as well as tensiometrical characteristics were significantly increased in the treatment groups compared to the control group, and these changes were more obvious in the HAM+MenSC ones (P<0.05). Moreover, the expression levels of TGF-β, bFGF, and VEGF genes were considerably increased in treatment groups compared to the control group and were greater in the HAM+MenSC group (P<0.05). This is while expression levels of TNF-α and IL-1β decreased more significantly in the HAM+MenSC group than the other groups (P<0.05). We concluded that the combined use of HAM and MenSCs has a more significant effect on diabetic wound healing.

Three-dimensional bioengineered dermal derived matrix scaffold in combination with adipose-derived stem cells accelerate diabetic wound healing

Due to the multifactorial nature of diabetic wounds, the most effective treatments require combinatorial approach. Herein we investigated whether engraftment of a bioengineered three-dimensional dermal derived matrix scaffold (DDMS) in combination with adipose-derived stem cells (ADSs), could accelerate diabetic wound healing. Diabetic animals were randomly planned into the control group, DDMS group, ADS group, and DDMS+ADS group. On days 7, 14, and 21, tissue samples were obtained for stereological, molecular, and tensiometrical assessments. We found that the wound contraction rate, the total volumes of new epidermis and dermis, the numerical densities of fibroblasts and blood vessels, collagen density, and tensiometrical parameters were meaningfully greater in the treated groups than in the control group, and these changes were more obvious in the DDMS+ADS ones (p < 0.05). Moreover, the expression of TGF-β, bFGF, and VEGF genes were considerably upregulated in treated groups compared to the control group and were greater in the DDMS+ADS group (p < 0.05). This is while expression of TNF-α and IL-1β, as well as the numerical densities of neutrophils and macrophages decreased more considerably in the DDMS+ADS group than in the other groups (p < 0.05). Overall, it was found that using both DDMS engraftment and ADS transplantation has more impact on diabetic wound healing.

Photobiomodulation and conditioned medium of adipose-derived stem cells for enhancing wound healing in rats with diabetes: an investigation on the proliferation phase

This investigation tried to evaluate the combined and solo effects of photobiomodulation (PBM) and conditioned medium derived from human adipose tissue-derived stem cells (h-ASC-CM) on the inflammatory and proliferative phases of an ischemic infected delayed healing wound model (IIDHWM) in rats with type I diabetes mellitus (TIDM). The present investigation consisted of four groups: group 1 served as the control, group 2 treated with h-ASC-CM, group 3 underwent PBM treatment, and group 4 received a combination of h-ASC-CM and PBM. Clinical and laboratory assessments were conducted on days 4 and 8. All treatment groups exhibited significantly higher wound strength than the group 1 (p = 0.000). Groups 4 and 3 demonstrated significantly greater wound strength than group 2 (p = 0.000). Additionally, all therapeutic groups showed reduced methicillin -resistant Staphylococcus aureus (MRSA) in comparison with group 1 (p = 0.000). While inflammatory reactions, including neutrophil and macrophage counts, were significantly lower in all therapeutic groups rather than group 1 on days 4 and 8 (p < 0.01), groups 4 and 3 exhibited superior results compared to group 2 (p < 0.01). Furthermore, proliferative activities, including fibroblast and new vessel counts, as well as the measurement of new epidermal and dermal layers, were significantly increased in all treatment groups on 4 and 8 days after the surgery (p < 0.001). At the same times, groups 4 and 3 displayed significantly higher proliferative activities compared to group 2 (p < 0.001). The treatment groups exhibited significantly higher mast cell counts and degranulation phenotypes in comparison with the group 1 on day 4 (p < 0.05). The treatment groups showed significantly lower mast cell counts and degranulation phenotypes than group 1 on day 8 (p < 0.05).The combined and individual application of h-ASC-CM and PBM remarkably could accelerate the proliferation phase of wound healing in the IIDHWM for TIDM in rats, as indicated by improved MRSA control, wound strength, and stereological evaluation. Furthermore, the combination of h-ASC-CM and PBM demonstrated better outcomes compared to the individual application of either h-ASC-CM or PBM alone.

Acceleration of a delayed healing wound repair model in diabetic rats by additive impacts of photobiomodulation plus conditioned medium of adipose-derived stem cells

Purpose

This study aimed to investigate the effects of photobiomodulation (PBM) and conditioned medium (CM) derived from human adipose-derived stem cells (h-ASCs), both individually and in combination, on the maturation stage of an ischemic infected delayed healing wound model (IIDHWM) in type I diabetic (TIDM) rats.

Methods

The study involved the extraction of h-ASCs from donated fat, assessment of their immunophenotypic markers, cell culture, and extraction and concentration of CM from cultured 1 × 10^6 h-ASCs. TIDM was induced in 24 male adult rats, divided into four groups: control, CM group, PBM group (80 Hz, 0.2 J/cm2, 890 nm), and rats receiving both CM and PBM. Clinical and laboratory evaluations were conducted on days 4, 8, and 16, and euthanasia was performed using CO2 on day 16. Tensiometrical and stereological examinations were carried out using two wound samples from each rat.

Results

Across all evaluated factors, including wound closure ratio, microbiological, tensiometrical, and stereological parameters, similar patterns were observed. The outcomes of CM + PBM, PBM, and CM treatments were significantly superior in all evaluated parameters compared to the control group (p = 0.000 for all). Both PBM and CM + PBM treatments showed better tensiometrical and stereological results than CM alone (almost all, p = 0.000), and CM + PBM outperformed PBM alone in almost all aspects (p = 0.000). Microbiologically, both CM + PBM and PBM exhibited fewer colony-forming units (CFU) than CM alone (both, p = 0.000).

Conclusion

PBM, CM, and CM + PBM interventions substantially enhanced the maturation stage of the wound healing process in IIDHWM of TIDM rats by mitigating the inflammatory response and reducing CFU count. Moreover, these treatments promoted new tissue formation in the wound bed and improved wound strength. Notably, the combined effects of CM + PBM surpassed the individual effects of CM and PBM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01285-3.

Assessing the role of combination of stem cell and light-based treatments on skin wound repair: A meta-analysis

The meta-analysis aims to evaluate and compare the impact of the combination of stem cells (SCs) and light-based treatments (LBTs) on skin wound (SW) repair. Examinations comparing SCs to LBT with SCs for SW repair was among the meta-analysis from various languages that met the inclusion criteria. Using continuous random-effect models, the results of these investigations were examined, and the mean difference (MD) with 95% confidence intervals was computed (CIs). Seven examinations from 2012 to 2022 were recruited for the current analysis including 106 animals with SWs. Photobiomodulation therapy (PBT) plus SCs had a significantly higher wound closure rate (WCR) (MD, 9.08; 95% CI, 5.55-12.61, p < 0.001) compared to SCs in animals with SWs. However, no significant difference was found between PBT plus SCs and SCs on wound tensile strength (WTS) (MD, 2.01; 95% CI, -0.42 to 4.44, p = 0.10) in animals with SWs. The examined data revealed that PBT plus SCs had a significantly higher WCR, however, no significant difference was found in WTS compared to SCs in animals with SWs. Nevertheless, caution should be exercised while interacting with its values since all the chosen examinations were found with a low sample size and a low number of examinations were found for the comparisons studied for the meta-analysis.

Exosomes derived from adipose stem cells in combination with hyaluronic acid promote diabetic wound healing

Diabetic wound is one of the main challenges in dermatology. Although stem cell-based treatment has therapeutic benefits in wound repair, the clinical application is still limited. Herein we investigated whether adipose stem cells -derived exosomes (Exo) loaded on hyaluronic acid (HA) could promote healing in diabetic rats. Sixty diabetic rats were randomly planned into the control group, Exo group, HA group, and HA+Exo group. On days 7, 14, and 21, five rats from each group were sampled for stereological, molecular, and tensiometrical assessments. Our results indicated that the wound closure rate, the total volumes of new epidermis and dermis, the numerical densities of fibroblasts, the length density blood vessels, collagen density as well as tensiometrical parameters of the healed wounds were significantly higher in the treated groups than in the control group, and these changes were more obvious in the HA+Exo ones. Furthermore, the expression of TGF-β and VEGF genes were meaningfully upregulated in all treated groups compared to the control group and were greater in the HA+Exo group. This is while expression of TNF-α and IL-1β, as well as numerical densities of neutrophils decreased more considerably in the HA+Exo group in comparison to the other groups. Generally, it was found that using both HA injection and exosomes has more effect on diabetic wound healing.

Facile fabrication of carboxymethylcellulose/ZnO/g-C3N4 containing nutmeg extract with photocatalytic performance for infected wound healing

New topical antibacterial agents are required to inhibit and development of bacteria and also promoting the wound healing process. This study was evaluating the healing effect of Myristica fragrans extract coated with carboxymethyl cellulose, zinc oxide and graphite carbon nitride (CMC/ZnO/g-C3N4/MyR) by photocatalytic process on the healing process of full-thickness infectious excision wounds in mice. Nanosheets were prepared and physicochemical properties were evaluated. Safety, in vitro release, antibacterial activities under in vitro and in vivo condition, wound contraction, histopathological properties and the protein expressions of tumor necrosis factor-α (TNF-α), collagen 1A (COL1A) and CD31 were also evaluated. Physicochemical properties confirmed their successful synthesis. Nanosheets exhibited antibacterial activity under in vitro and in vivo conditions. The formulations containing CMC/ZnO/g-C3N4/MyR, significantly (P < 0.05) competed with standard ointment of mupirocin for accelerating the wound healing process due to their effects on bacterial count and the expression of TNF-α and also accelerating the proliferative phase. This structure can be used as a safe structure in combination with other agents for accelerating the wound healing process following future clinical studies.

Anti-inflammatory, Antioxidant, and Wound-Healing Effects of Photobiomodulation on Type-2 Diabetic Rats

Introduction: In the current study, the effects of photobiomodulation (PBM) treatments were examined based on biomechanical and histological criteria and mRNA levels of catalase (CAT), superoxide dismutase (SOD), and NADPH oxidase (NOX) 1 and 4 in a postponed, ischemic, and infected wound repair model (DIIWHM) in rats with type 2 diabetes (DM2) during the inflammation (day 4) and proliferation (day 8) stages. Methods: To study ischemic wound repair in a diabetic rat model (DIIWHM), 24 rats with type-2 diabetes were randomly divided into four groups and infected with methicillin-resistant Staphylococcus aureus (MRSA). The control groups consisted of CG4 (control group on day 4) and CG8 (control group on day 8), while the PBM groups comprised PBM4 (PBM treatment group on day 4) and PBM8 (PBM treatment group on day 8). These group assignments allowed for comparisons between the control groups and the PBM-treated groups at their respective time points during the study. Results: On days 4 and 8 of wound restoration, the PBM4 and PBM8 groups showed substantially modulated inflammatory responses and improved formation of fibroblast tissue compared with the CG groups (P<0.05). Concurrently, the effects of PBM8 were significantly superior to those of PBM4 (P<0.05). The antioxidant results on days 4 and 8 revealed substantial increases in CAT and SOD in the PBM groups compared with the CGs (P<0.05). Substantial decreases were observed in the antioxidant agents NOX1 and NOX4 of the PBM4 and PBM8 groups compared with both CGgroups (P<0.05). Conclusion: PBM treatments significantly sped up the inflammatory and proliferating processes in a DHIIWM in DM2 animals by modifying the inflammatory reaction and boosting fibroblast proliferation. Overall, the current findings indicated substantially better results in the PBM groups than in the CG groups.

Application of combined photobiomodulation and curcumin-loaded iron oxide nanoparticles considerably enhanced repair in an infected, delayed-repair wound model in diabetic rats compared to either treatment alone

Herein, we attempted to evaluate the therapeutic potential of photobiomodulation (PBM) and curcumin-loaded iron nanoparticles (CUR), alone and in combination, on wound closure rate (WCR), microbial flora by measuring colony-forming units (CFUs), the stereological and biomechanical properties of repairing wounds in the maturation stage of the wound healing course in an ischemic infected delayed healing wound model (IIDHWM) of type I diabetic (TIDM) rats. There were four groups: group 1 was the control, group 2 received CUR, rats in group 3 were exposed to PBM (80 Hz, 890 nm, and 0.2 J/cm2), and rats in group 4 received both PBM and CUR (PBM + CUR). We found CFU was decreased in groups 2, 3, and 4 compared to group 1 (p = 0.000 for all). Groups 2, 3, and 4 showed a considerable escalation in WCR compared to group 1 (p = 0.000 for all). In terms of wound strength parameters, substantial increases in bending stiffness and high-stress load were observed in groups 2, 3, and 4 compared to group 1 (p = 0.000 for all). Stereological examinations revealed decreases in neutrophil and macrophage counts and increases in fibroblast counts in groups 2, 3, and 4compared  to group 1 (p = 0.000 for all). Blood vessel counts were more dominant in the PBM and PBM + CUR groups over group 1 (p = 0.000 for all). CFU and wound strength as well as macrophage, neutrophil, and fibroblast counts were found to be improved in the PBM + CUR and PBM groups compared to the CUR group (ranging from p = 0.000 to p < 0.05). Better results were achieved in the PBM + CUR  treatment  over the PBM therapy. We determined therapy with PBM + CUR, PBM alone, and CUR alone substantially accelerated diabetic wound healing in an IIDHWM of TIDM rats compared to control  group. Concomitantly, the PBM + CUR and PBM groups attained significantly enhanced results for WCR, stereological parameters, and wound strength than the CUR group, with the PBM + CUR results being superior to those of the PBM group.

The stereological, immunohistological, and gene expression studies in an infected ischemic wound in diabetic rats treated by human adipose-derived stem cells and photobiomodulation

We investigated the impacts of photobiomodulation (PBM) and human allogeneic adipose-derived stem cells (ha-ADS) together and or alone applications on the stereological parameters, immunohistochemical characterizing of M1 and M2 macrophages, and mRNA levels of hypoxia-inducible factor (HIF-1α), basic fibroblast growth factor (bFGF), vascular endothelial growth factor-A (VEGF-A) and stromal cell-derived factor-1α (SDF-1α) on inflammation (day 4) and proliferation phases (day 8) of repairing tissues in an infected delayed healing and ischemic wound model (IDHIWM) in type 1 diabetic (DM1) rats. DM1 was created in 48 rats and an IDHIWM was made in all of them, and they were distributed into 4 groups. Group1 = control rats with no treatment. Group2 = rats received (10 × 100000 ha-ADS). Group3 = rats exposed to PBM (890 nm, 80 Hz, 3.46 J/cm2). Group4 = rats received both PBM and ha-ADS. On day 8, there were significantly higher neutrophils in the control group than in other groups (p < 0.01). There were substantially higher macrophages in the PBM + ha-ADS group than in other groups on days 4 and 8 (p < 0.001). Granulation tissue volume, on both days 4 and 8, was meaningfully greater in all treatment groups than in the control group (all, p = 0.000). Results of M1 and M2 macrophage counts of repairing tissue in the entire treatment groups were considered preferable to those in the control group (p < 0.05). Regarding stereological and macrophage phenotyping, the results of the PBM + ha-ADS group were better than the ha-ADS and PBM groups. Results of the tested gene expression of repairing tissue on inflammation and proliferation steps in PBM and PBM + ha-ADS groups were meaningfully better than the control and ha-ADS groups (p < 0.05). We showed that PBM, ha-ADS, and PBM plus ha-ADS, hastened the proliferation step of healing in an IDHIWM in rats with DM1 by regulation of the inflammatory reaction, macrophage phenotyping, and augmented granulation tissue formation. In addition PBM and PBM plus ha-ADS protocols hastened and increased mRNA levels of HIF-1α, bFGF, SDF-1α, and VEGF-A. Totally, in terms of stereological and immuno-histological tests, and also gene expression HIF-1α and VEGF-A, the results of PBM + ha-ADS were superior (additive) to PBM, and ha-ADS alone treatments.

Combined Use of Photobiomodulation and Curcumin-Loaded Iron Oxide Nanoparticles Significantly Improved Wound Healing in Diabetic Rats Compared to Either Treatment Alone

Introduction: Here, we assess the therapeutic effects of photobiomodulation (PBM) and curcumin (CUR)-loaded superparamagnetic iron oxide nanoparticles (SPIONs), alone or together, on the maturation step of a type 1 diabetes (DM1) rat wound model. Methods: Full-thickness wounds were inflicted in 36 rats with diabetes mellitus (DM) induced by the administration of streptozotocin (STZ). The rats were randomly allocated to four groups. Group one was untreated (control); group two received CUR; group 3 received PBM (890 nm, 80 Hz, 0.2 J/cm2); group 4 received a combination of PBM plus CUR. On days 0, 4, 7, and 15, we measured microbial flora, wound closure fraction, tensile strength, and stereological analysis. Results: All treatment groups showed a substantial escalation in the wound closure rate, a substantial reduction in the count of methicillin-resistant Staphylococcus aureus (MRSA), a substantial improvement in wound strength, a substantially improvement in stereological parameters compared to the control group, however, the PBM+CUR group was superior to the other treatment groups (all, P≤0.05). Conclusion: All treatment groups showed significantly improved wound healing in the DM1 rat model. However, the PBM+CUR group was superior to the other treatment groups and the control group in terms of wound strength and stereological parameters.

Accelerated wound healing using three-dimensional amniotic membrane scaffold in combination with adipose-derived stem cells in a diabetic rat model

The most important factors in the non-optimal healing of diabetic wounds are the lack of a suitable scaffold in the wound site for the migration and replacement of cells, as well as the lack of blood supply and effective growth factors in the wound site. Herein we investigated whether a bioengineered micro-porous three-dimensional decellularized amniotic membrane-scaffold (DAMS) in combination with adipose-derived stem cells (ASCs) could promote healing in ischemic wounds in diabetic type 1 rat. The diabetic animals were randomly divided into non-treated (untreated group), engraftment by DAMS (DAMS group), transplanted by ASCs (ASC group), and DAMS in combination with ASCs (DAMS+ASC group). Stereological, immunohistochemical, molecular, and tensiometrical assessments were performed on post-surgical days 7, 14, and 21. We found that the rate of wound closure, the volumes of new epidermis and dermis, the numerical density of fibroblasts and blood vessels, the numbers of proliferating cells and collagen deposition as well as biomechanical properties of the healed wounds were significantly higher in the treatment groups in comparison to the untreated group, and were the highest in DAMS+ASC ones. The transcripts for TGF-β and VEGF genes were significantly upregulated in all treatment regimens compared to the untreated group and were the highest for DAMS+ASC group. This is while expression of TNF-α and IL-1β as well as cell density of neutrophils decreased more significantly in DAMS+ASC group as compared with other groups. Overall, it was found that using both DAMS engraftment and ASC transplantation has more impact on diabetic wound healing.

Decellularized human amniotic membrane engraftment in combination with adipose-derived stem cells transplantation, synergistically improved diabetic wound healing

BACKGROUND

One of the most important and common complications of diabetes is a disorder and defect in diabetic wound healing.

AIMS

The aim of present study was to investigate the synergistic effects of decellularized human amniotic membrane (dHAM) engraftment and adipose-derived stem cells (ADSs) transplantation in the healing of delayed and ischemic diabetic wound.

METHODS

Sixty diabetic male rats were randomly divided into four groups (n = 15), including untreated (Control) group, engraftment by dHAM (dHAM) group, transplanted by ADSs (ADS) group, and engraftment by dHAM plus transplanted by ADSs (dHAM + ADS) group. Sampling was performed on Days 7, 14, and 21 after surgery. Evaluation tests included stereology, immunohistochemistry, molecular, and biomechanical.

RESULTS

Our results showed that the wound closure rate, volumes of newly formed epidermis and dermis, density of fibroblasts and blood vessels, collagen deposition, density of proliferation cells, expression levels of TGF-β and VEGF genes, and biomechanical characteristics were significantly higher in all treated groups compared with control group; however, these changes were considerable in the combination group. This is while that the density of neutrophils and expression levels of TNF-α and IL-1β genes in the treated groups, especially in the combination group, were significantly reduced compared with control group.

CONCLUSION

Generally, the simultaneous use of dHAM and ADS accelerates healing and improves the quality of repaired diabetic wounds.

Effect of composite biodegradable biomaterials on wound healing in diabetes

The repair of diabetic wounds has always been a job that doctors could not tackle quickly in plastic surgery. To solve this problem, it has become an important direction to use biocompatible biodegradable biomaterials as scaffolds or dressing loaded with a variety of active substances or cells, to construct a wound repair system integrating materials, cells, and growth factors. In terms of wound healing, composite biodegradable biomaterials show strong biocompatibility and the ability to promote wound healing. This review describes the multifaceted integration of biomaterials with drugs, stem cells, and active agents. In wounds, stem cells and their secreted exosomes regulate immune responses and inflammation. They promote angiogenesis, accelerate skin cell proliferation and re-epithelialization, and regulate collagen remodeling that inhibits scar hyperplasia. In the process of continuous combination with new materials, a series of materials that can be well matched with active ingredients such as cells or drugs are derived for precise delivery and controlled release of drugs. The ultimate goal of material development is clinical transformation. At present, the types of materials for clinical application are still relatively single, and the bottleneck is that the functions of emerging materials have not yet reached a stable and effective degree. The development of biomaterials that can be further translated into clinical practice will become the focus of research.

Potential of stem cells for treating infected Diabetic Foot Wounds and Ulcers: a systematic review

Infected diabetic foot ulcers (iDFUs) cause great concern, as they generally heal poorly and are precursive of diabetic-related foot amputation and even death. Scientists have tested various techniques in attempts to ascertain the best treatment for iDFUs; however, the results have remained inconclusive. Stem cell therapy (SCT) appears to improve iDFU through its antimicrobial impacts, yet cogent information regarding the repair of iDFUs with SCT is lacking. Herein, published articles are evaluated to report coherent information about the antimicrobial effects of SCT on the repair of iDFUs in diabetic animals and humans. In this systematic review, we searched the Scopus, Medline, Google Scholar, and Web of Science databases for relevant full-text English language articles published from 2000 to 2022 that described stem cell antimicrobial treatments, infected diabetic wounds, or ulcers. Ultimately, six preclinical and five clinical studies pertaining to the effectiveness of SCT on healing infected diabetic wounds or ulcers were selected. Some of the human studies confirmed that SCT is a promising therapy for diabetic wounds and ulcers. Notably, more controlled studies performed on animal models revealed that stem cells combined with a biostimulator such as photobiomodulation decreased colony forming units and hastened healing in infected diabetic wounds. Moreover, stem cells alone had lower therapeutic impact than when combined with a biostimulant.

NIR irradiation of human buccal fat pad adipose stem cells and its effect on TRP ion channels

The effect of near infrared (NIR) laser irradiation on proliferation and osteogenic differentiation of buccal fat pad-derived stem cells and the role of transient receptor potential (TRP) channels was investigated in the current research. After stem cell isolation, a 940 nm laser with 0.1 W, 3 J/cm² was used in pulsed and continuous mode for irradiation in 3 sessions once every 48 h. The cells were cultured in the following groups: non-osteogenic differentiation medium/primary medium (PM) and osteogenic medium (OM) groups with laser-irradiated (L +), without irradiation (L -), laser treated + Capsazepine inhibitor (L + Cap), and laser treated + Skf96365 inhibitor (L + Skf). Alizarin Red staining and RT-PCR were used to assess osteogenic differentiation and evaluate RUNX2, Osterix, and ALP gene expression levels. The pulsed setting showed the best viability results (P < 0.05) and was used for osteogenic differentiation evaluations. The results of Alizarin red staining were not statistically different between the four groups. Osterix and ALP expression increased in the (L +) group. This upregulation abrogated in the presence of Capsazepine, TRPV1 inhibitor (L + Cap); however, no significant effect was observed with Skf96365 (L + Skf).

Activation of Wnt/β-Catenin Signaling Involves 660 nm Laser Radiation on Epithelium and Modulates Lipid Metabolism

Research has proven that light treatment, specifically red light radiation, can provide more clinical benefits to human health. Our investigation was firstly conducted to characterize the tissue morphology of mouse breast post 660 nm laser radiation with low power and long-term exposure. RNA sequencing results revealed that light exposure with a higher intervention dosage could cause a number of differentially expressed genes compared with a low intervention dosage. Gene ontology analysis, protein–protein interaction network analysis, and gene set enrichment analysis results suggested that 660 nm light exposure can activate more transcription-related pathways in HC11 breast epithelial cells, and these pathways may involve modulating critical gene expression. To consider the critical role of the Wnt/T-catenin pathway in light-induced modulation, we hypothesized that this pathway might play a major role in response to 660 nm light exposure. To validate our hypothesis, we conducted qRT-PCR, immunofluorescence staining, and Western blot assays, and relative results corroborated that laser radiation could promote expression levels of β-catenin and relative phosphorylation. Significant changes in metabolites and pathway analysis revealed that 660 nm laser could affect nucleotide metabolism by regulating purine metabolism. These findings suggest that the Wnt/β-catenin pathway may be the major sensor for 660 nm laser radiation, and it may be helpful to rescue drawbacks or side effects of 660 nm light exposure through relative interventional agents.

The Combined Effects of a Methacrylate Powder Dressing (Altrazeal Powder) and Photobiomodulation Therapy on the Healing of a Severe Diabetic Foot Ulcer in a Diabetic Patient: A Case Report

Weakened wound healing is a popular, severe complication of patients with diabetes which poses a risk for foot infection and amputation. Researchers have searched for new treatments for treating diabetic foot ulcers (DFUs) in recent years. In this case report, for the first time, we applied photobiomodulation therapy (PBMT) and Altrazeal powder together to treat a severe case of DFU in a 47-year-old woman who was suffering from type 1 diabetes. Along with the progress of combination therapy, we observed that the ulcer area was significantly reduced, and the wound healed within 16 weeks. Furthermore, dermatitis and purulent secretion were treated, and the pain was reduced. This reported case study indicated the beneficial effect of the combination of PBMT and Altrazeal powder for the healing of a severe DFU in a patient with type one diabetes. The combined application of PBMT plus Altrazeal powder demonstrated an additive effect. Further clinical trials in the clinical setting are suggested to validate the results further. Besides, more studies in preclinical models are suggested to find the mechanism of the action of combination therapy.

Impact of photobiomodulation on macrophages and their polarization during diabetic wound healing: a systematic review

This review aims to providing essential information and the current knowledge about the potential role of macrophages, especially their M2 subtypes in different diabetic wounds both in clinical and pre-clinical models under the influence of photobiomodulation (PBM). The long-term goal is to advance the macrophage-based therapies to accelerate healing of diabetic foot ulcers. We reviewed all databases provided by PubMed, Google Scholar, Scopus, Web of Science, and Cochrane precisely from their dates of inception to 25/10/2021. The keywords of Diabetes mellitus diseases, wound healing, macrophage, and photobiomodulation or low-level laser therapy were used in this systematic review.A total of 438 articles were initially identified in pubmed.ncbi.nlm.nih.gov (15 articles), Google scholar (398 articles), Scopus (18 articles), and Web of Science (7 articles). Four hundred sixteen articles that remained after duplicate studies (22 articles) were excluded. After screening abstracts and full texts, 14 articles were included in our analysis. Among them, 4 articles were about the effect of PBM on macrophages in type 2 diabetes and also found 10 articles about the impact of PBM on macrophages in type 1 diabetes. The obtained data from most of the reviewed studies affirmed that the PBM alone or combined with other agents (e.g., stem cells) could moderate the inflammatory response and accelerate the wound healing process in pre-clinical diabetic wound models. However, only very few studies conducted the detailed functions of polarized macrophages and M2 subtypes in wound healing of diabetic models under the influence of PBM. Further pre-clinical and clinical investigations are still needed to investigate the role of M2 macrophages, especially its M2c subtype, in the healing processes of diabetic foot ulcers in clinical and preclinical settings.

Could Light-Based Technologies Improve Stem Cell Therapy for Skin Wounds? A Systematic Review and Meta-Analysis of Preclinical Studies

Several diseases or conditions cause dermatological disorders that hinder the process of skin repair. The search for novel technologies has inspired the combination of stem cell (SC) and light-based therapies to ameliorate skin wound repair. Herein, we systematically revised the impact of photobiomodulation therapy (PBM) combined with SCs in animal models of skin wounds and quantitatively evaluated this effect through a meta-analysis. For inclusion, SCs should be irradiated in vitro or in vivo, before or after being implanted in animals, respectively. The search resulted in nine eligible articles, which were assessed for risk of bias. For the meta-analysis, studies were included only when PBM was applied in vivo, five regarding wound closure, and three to wound strength. Overall, a positive influence of SC+PBM on wound closure (MD: 9.69; 95%CI: 5.78 to 13.61, p<0.00001) and strength (SMD: 1.7, 95%CI: 0.68 to 2.72, p=0.001) was detected, although studies have shown moderate to high heterogeneity and a lack of information regarding some bias domains. Altogether, PBM seems to be an enabling technology able to be applied post-implantation of SCs for cutaneous regeneration. Our findings may guide future laboratory and clinical studies in hopes of offering wound care patients a better quality of life.

Photobiomodulation isolated or associated with adipose-derived stem cells allograft improves inflammatory and oxidative parameters in the delayed-healing wound in streptozotocin-induced diabetic rats

The single and associated impressions of photobiomodulation (PBM) and adipose-derived stem cells (ADS) on stereological parameters (SP), and gene expression (GE) of some antioxidant and oxidative stressors of repairing injured skin at inflammation and proliferation steps (days 4 and 8) of a delayed healing, ischemic, and infected wound model (DHIIWM) were examined in type one diabetic (DM1) rats. DM1 was induced by administration of streptozotocin (40 mg/kg) in 48 rats. The DHIIWM was infected by methicillin-resistant Staphylococcus aureus (MRSA). The study comprised 4 groups (each, n = 6): Group 1 was the control group (CG). Group 2 received allograft human (h) ADSs transplanted into the wound. In group 3, PBM (890 nm, 80 Hz, 0.2 J/cm²) was emitted, and in group 4, a combination of PBM+ADS was used. At both studied time points, PBM+ADS, PBM, and ADS significantly decreased inflammatory cell count (p < 0.05) and increased granulation tissue formation compared to CG (p < 0.05). Similarly, there were lower inflammatory cells, as well as higher granulation tissue in the PBM+ADS compared to those of alone PBM and ADS (all, p < 0.001). At both studied time points, the GE of catalase (CAT) and superoxide dismutase (SOD) was remarkably higher in all treatment groups than in CG (p < 0.05). Concomitantly, the outcomes of the PBM+ADS group were higher than the single effects of PBM and ADS (p < 0.05). On day 8, the GE of NADPH oxidase (NOX) 1 and NOX4 was substantially less in the PBM+ADS than in the other groups (p < 0.05). PBM+ADS, PBM, and ADS treatments significantly accelerated the inflammatory and proliferative stages of wound healing in a DIIWHM with MRSA in DM1 rats by decreasing the inflammatory response, and NOX1 and 4 as well; and also increasing granulation tissue formation and SOD and CAT. The associated treatment of PBM+ADS was more effective than the individual impacts of alone PBM and ADS because of the additive anti-inflammatory and proliferative effects of PBM plus ADS treatments.

The effects of Feijoa sellowiana fruit extract on wound healing in rats: a stereological and molecular study

OBJECTIVE

The aim of this study was to evaluate the anti-inflammatory and wound-healing potential of Feijoa sellowiana fruit extract using stereological and molecular methods in experimental rat models.

MATERIALS

Male Wistar rats were divided into four equal groups: non-treated, vehicle, Feijoa sellowiana fruit extract ointment (5% weight/weight) and the reference drug (madecassol). All animals were treated topically once per day. At the end of the study, wound samples were harvested for histological, stereological, immunohistochemical and molecular assessments to determine the in vivo healing potential and anti-inflammatory activity. A high-performance liquid chromatography (HPLC) analysis was performed for the characterisation of the phenolic acids in the extract.

RESULTS

The study included 64 rats in total. Our results showed that the wound closure, volume of new epidermis and dermis, density of fibroblasts and blood vessels, and the deposition of collagen were significantly higher in both extract and madecassol groups compared to the non-treated and vehicle groups, with superior healing in the extract group. The transcript for the transforming growth factor (TGF)-β gene was significantly upregulated in both extract and madecassol groups compared to non-treated and vehicle groups and was highest for the extract group. The density of inflammatory cells and expression levels of the cyclooxygenase (COX)-2 protein and tumour necrosis factor (TNF)-α gene in the extract and madecassol groups, especially in the extract group, were significantly reduced compared to non-treated and vehicle groups.

CONCLUSION

Our results confirm that the Feijoa sellowiana fruit extract is a valuable source of antioxidant and anti-inflammatory activities and can allow for damaged tissue in wounds to recover markedly.

SDF-1α loaded bioengineered human amniotic membrane-derived scaffold transplantation in combination with hyperbaric oxygen improved diabetic wound healing

Based on its multifactorial nature, successful treatment of diabetic wounds requires combinatorial approach. In this regard, we hypothesized that engraftment of a bioengineered micro-porous three-dimensional human amniotic membrane-scaffold (HAMS) loaded by SDF-1α (SHAMS) in combination with hyperbaric oxygen (HBO), throughout mobilization and recruitment of endothelial progenitor cells (EPCs), could accelerate wound healing in rats with type 1 diabetes mellitus. To test this hypothesis, 30 days after inducting diabetes, an ischemic wound was created in rat skin and treatments were performed for 21 days. In addition to wounded non-diabetic (ND) group, diabetic animals were randomly divided into non-treated (NT-D), HBO-treated (HBO-D), HBO-treated plus HAMS transplantation (HBO+HAMS-D) or HBO-treated in combination with SHAMS transplantation (HBO+SHAMS-D) groups. Our results on post-wounding days 7, 14 and 21 showed that the wound closure, volume of new dermis and epidermis, numerical density of basal cells of epidermis, fibroblasts and blood vessels, number of proliferating cells, deposition of collagen and biomechanical properties of healed wound were considerably higher in both HBO+HAMS-D and HBO+SHAMS-D groups in comparison to those of the NT-D and HBO-D groups, and were the highest in HBO+SHAMS-D ones. The transcripts for Vegf, bFgf, and Tgf-β genes were significantly upregulated in all treatment regimens compared to NT-D group and were the highest for HBO+SHAMS-D group. This is while expression of Tnf-α and Il-1β as well as cell density of neutrophil and macrophage decreased more significantly in HBO+SHAMS-D group as compared with NT-D or HBO-D groups. Overall, it was found that using both HAMS transplantation and HBO treatment has more impact on diabetic wound healing. Moreover, SDF-1α loading on HAMS could transiently improve the wound healing process, as compared with the HBO+HAMS-D group on day 7 only.

The effect of photobiomodulation therapy on antioxidants and oxidative stress profiles of adipose derived mesenchymal stem cells in diabetic rats

We studied the effects of photobiomodulation therapy (PBMT) on adipose-derived mesenchymal stem cells (ADSCs) which were extracted from streptozotocin (STZ) induced diabetic rats. Adipose tissue was extracted from the hypodermis of diabetic rats, and diabetic ADSCs were extracted, characterized, and cultured. There were two in vitro groups: control-diabetic ADSCs, and PBMT-diabeticADSCs. We used 630 nm and 810 nm laser at 1.2 J/cm² with 3 applications 48 h apart. We measured cell viability, apoptosis, population doubling time (PDT), and reactive oxygen species (ROS) by flow cytometry. Gene expression of antioxidants, including cytosolic copper-zinc superoxide dismutase (SOD1), catalase (CAT), total antioxidant capacity (TAC), and oxidative stress biomarkers (NADPH oxidase 1 and 4) by quantitative real time (qRT) - PCR. In this study, data were analyzed using t-test. Viability of PBMT-diabetic- ADSC group was higher than control- diabetic-ADSC (p = 0.000). PDT and apoptosis of PBMT- diabetic-ADSC group were lower than control-diabetic -ADSC (p = 0.001, p = 0.02). SOD1 expression and TAC of PBMT- diabetic-ADSC group were higher than control -diabetic -ADSC (p = 0.018, p = 0.005). CAT of PBMT -diabetic-ADSC group was higher than control-diabetic -ADSC. ROS, NOX1, and NOX4 of PBMT- diabetic -ADSC group were lower than control-diabetic-ADSC (p = 0.002, p = 0.021, p = 0.017). PBMT may improve diabetic- ADSC function in vitro by increasing levels of cell viability, and gene expression of antioxidant agents (SOD1, CAT, and TAC), and significantly decreasing of levels of PDT, apoptosis, ROS, and gene expression of oxidative stress biomarkers (NOX1 and NOX4).

Combined Treatment of Photobiomodulation and Arginine on Chronic Wound Healing in an Animal Model

Introduction: Herein, the individual and combined effects of photobiomodulation (PBM) and arginine (ARG) on the wound healing course of an experimental model of a slow healing wound (ulcer) in rats were assessed. Methods: A total of 108 male rats were divided into 6 groups: control; lower energy density (low)-PBM; arginine ointment (ARG); low-PBM+ARG; high energy density (high)-PBM; and high-PBM+ARG. In each rat, one ischemic wound in the center of a bipedicle flap and one non-ischemic wound out of the flap were created. Both wounds were treated in the experimental groups. Microbial growth, wound area, and wound strength were assessed on days 0, 5, 10, 15, and 20 after wound infliction. Results: All non-ischemic wounds closed before day 15. High-PBM+ARG and ARG significantly increased wound closure rates compared to the control group (LSD test, P = 0.000, and P = 0.001, respectively) on day 10. All slow healing wounds were open on day 15 but closed completely before day 20. Low-PBM+ARG and high-PBM significantly increased wound strength (stress high load, SHL) on day 10 compared to the control group (LSD test, P = 0.001, and P = 0.000, respectively). ARG, high-PBM, and low-PBM+ARG significantly increased wound closure rates on day 15 relative to the control group (LSD test, P = 0.000, P = 0.000, and P = 0.001, respectively). Conclusion: High-PBM and low-PBM+ARG have biostimulatory and antibacterial effects on slow-healing wounds, which were shown by significant increases in wound closure rates, wound strength, and inhibition of Staphylococcus aureus growth.

Effectiveness of preconditioned adipose-derived mesenchymal stem cells with photobiomodulation for the treatment of diabetic foot ulcers: a systematic review

The primary goal of this systematic review article was to provide an outline of the use of diabetic autologous adipose-derived mesenchymal stem cells (DAAD-MSCs) in the treatment of wounds and ulcers in animal models and patients with diabetes mellitus (DM). The secondary goal was to present the outcomes of pretreatment of diabetic adipose-derived mesenchymal stem cells (DAD-MSCs) with probable different agents in the treatment of diabetic foot ulcers (DFUs) and wounds. In view of possible clinical applications of AD-MSC-mediated cell therapy for DFUs, it is essential to evaluate the influence of DM on AD-MSC functions. Nevertheless, there are conflicting results about the effects of DAAD-MSCs on accelerating wound healing in animals and DM patients. Multistep research of the MEDLINE, PubMed, Embase, Clinicaltrials.gov, Scopus database, and Cochrane databases was conducted for abstracts and full-text scientific papers published between 2000 and 2020. Finally, 5 articles confirmed that the usage of allogeneic or autologous AD-MSCs had encouraging outcomes on diabetic wound healing. One study reported that DM changes AD-MSC function and therapeutic potential, and one article recommended that the pretreatment of diabetic allogeneic adipose-derived mesenchymal stem cells (DAlD-MSCs) was more effective in accelerating diabetic wound healing. Recently, much work has concentrated on evolving innovative healing tactics for hastening the repair of DFUs. While DM alters the intrinsic properties of AD-MSCs and impairs their function, one animal study showed that the pretreatment of DAlD-MSCs in vitro significantly increased the function of DAlD-MSCs compared with DAlD-MSCs without any treatment. Preconditioning diabetic AD-MSCs with pretreatment agents like photobiomodulation (PBM) significantly hastened healing in delayed-healing wounds. It is suggested that further animal and human studies be conducted in order to provide more documentation. Hopefully, these outcomes will help the use of DAAD-MSCs plus PBM as a routine treatment protocol for healing severe DFUs in DM patients.

Impact of preconditioned diabetic stem cells and photobiomodulation on quantity and degranulation of mast cells in a delayed healing wound simulation in type one diabetic rats

Herein, we report the influence of administering different protocols of preconditioned diabetic adipose-derived mesenchymal stem cells (ADSs) with photobiomodulation in vitro, and photobiomodulation in vivo on the number of mast cells (MCs), their degranulation, and wound strength in the maturation step of a Methicillin-resistant Staphylococcus aureus (MRSA)-infectious wound model in rats with type one diabetes. An MRSA-infectious wound model was generated on diabetic animals, and they were arbitrarily assigned into five groups (G). G1 were control rats. In G2, diabetic ADS were engrafted into the wounds. In G3, diabetic ADS were engrafted into the wound, and the wound was exposed to photobiomodulation (890 nm, 890 ± 10 nm, 80 Hz, 0.2 J/cm²) in vivo. In G4, preconditioned diabetic ADS with photobiomodulation (630 and 810 nm; each 3 times with 1.2 J/cm²) in vitro were engrafted into the wound. In G5, preconditioned diabetic ADS with photobiomodulation were engrafted into the wound, and the wound was exposed to photobiomodulation in vivo. The results showed that, the maximum force in all treatment groups was remarkably greater compared to the control group (all, p = 0.000). Maximum force in G4 and G5 were superior than that other treated groups (both p = 0.000). Moreover, G3, G4, and G5 showed remarkable decreases in completely released MC granules and total numbers of MC compared to G1 and G2 (all, p = 0.000). We concluded that diabetic rats in group 5 showed significantly better results in terms of accelerated wound healing and MC count of an ischemic infected delayed healing wound model.

Combined Treatment of Photobiomodulation and Arginine on Chronic Wound Healing in an Animal Model

Introduction: Herein, the individual and combined effects of photobiomodulation (PBM) and arginine (ARG) on the wound healing course of an experimental model of a slow healing wound (ulcer) in rats were assessed. Methods: A total of 108 male rats were divided into 6 groups: control; lower energy density (low)-PBM; arginine ointment (ARG); low-PBM+ARG; high energy density (high)-PBM; and high-PBM+ARG. In each rat, one ischemic wound in the center of a bipedicle flap and one non-ischemic wound out of the flap were created. Both wounds were treated in the experimental groups. Microbial growth, wound area, and wound strength were assessed on days 0, 5, 10, 15, and 20 after wound infliction. Results: All non-ischemic wounds closed before day 15. High-PBM+ARG and ARG significantly increased wound closure rates compared to the control group (LSD test, P=0.000, and P=0.001, respectively) on day 10. All slow healing wounds were open on day 15 but closed completely before day 20. Low-PBM+ARG and high-PBM significantly increased wound strength (stress high load, SHL) on day 10 compared to the control group (LSD test, P=0.001, and P=0.000, respectively). ARG, high-PBM, and low-PBM+ARG significantly increased wound closure rates on day 15 relative to the control group (LSD test, P=0.000, P=0.000, and P=0.001, respectively). Conclusion: High-PBM and low-PBM+ARG have biostimulatory and antibacterial effects on slow-healing wounds, which were shown by significant increases in wound closure rates, wound strength, and inhibition of Staphylococcus aureus growth.

Photobiomodulation: An Effective Approach to Enhance Proliferation and Differentiation of Adipose-Derived Stem Cells into Osteoblasts

Osteoporosis is regarded as the most common chronic metabolic bone condition in humans. In osteoporosis, bone mesenchymal stem cells (MSCs) have reduced cellular function. Regenerative medicine using adipose-derived stem cell (ADSC) transplantation can promote the growth and strength of new bones, improve bone stability, and reduce the risk of fractures. Various methods have been attempted to differentiate ADSCs to functioning specialized cells for prospective clinical application. However, commonly used therapies have resulted in damage to the donor site and morbidity, immune reactions, carcinogenic generation, and postoperative difficulties. Photobiomodulation (PBM) improves ADSC differentiation and proliferation along with reducing clinical difficulties such as treatment failures to common drug therapies and late initiation of treatment. PBM is a noninvasive, nonthermal treatment that encourages cells to produce more energy and to undergo self-repair by using visible green and red and invisible near-infrared (NIR) radiation. The use of PBM for ADSC proliferation and differentiation has been widely studied with multiple outcomes observed due to laser fluence and wavelength dependence. In this article, the potential for differentiating ADSCs into osteoblasts and the various methods used, including biological induction, chemical induction, and PBM, will be addressed. Likewise, the optimal laser parameters that could improve the proliferation and differentiation of ADSC, translating into clinical success, will be commented on.

Low-power lasers on bacteria: stimulation, inhibition, or effectless?

Clinical protocols based on low-power lasers have been widely used for inflammation process resolution improvement, pain relief, wound healing, and nerve regeneration. However, there are concerns if exposure to such lasers could have negative effects on infected organs and tissues. There are experimental data suggesting exposure to radiations emitted by low-power lasers either induces stimulation, inhibition, or it is effectless on bacterial cultures. Thus, this review aimed to carry out a review of studies and to propose a hypothesis to explain why exposure to low-power lasers could stimulate, inhibit, or have no effect on bacteria. A literature search was carried out for assessment of published reports on effect of low-power lasers on bacteria. The experimental data suggest that keys for determining laser-induced effects on bacteria are specific physical laser and biological parameters. Final consequence on bacterial cells could depend on exposure to low-power laser which could either cause more stimulation of endogenous photoacceptors, more excitation of endogenous photosensitizers, or a balance between such effects.

In Vitro Wound Healing Potential of Photobiomodulation Is Possibly Mediated by Its Stimulatory Effect on AKT Expression in Adipose-Derived Stem Cells

Increasing evidence suggests that adipose-derived stem cells (ADSCs) serve as a therapeutic approach for wound healing. The aim of this study was to determine the effect of photobiomodulation (PBM) on antioxidant enzymes in ADSCs. Four ADSC cell models, namely, normal, wounded, diabetic, and diabetic wounded, were irradiated with 660 nm (fluence of 5 J/cm² and power density of 11.2 mW/cm²) or 830 nm (fluence of 5 J/cm² and power density of 10.3 mW/cm²). Nonirradiated cells served as controls. Cell morphology and wound migration were determined using light microscopy. Cell viability was determined by the trypan blue exclusion assay. The enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of antioxidants (superoxide dismutase (SOD), catalase (CAT), and heme oxygenase (HMOX1)). AKT activation and FOXO1 levels were determined by immunofluorescence and western blotting. The gaps (wound) in PBM-treated wounded and diabetic wounded cell models closed faster than the controls. PBM treatment significantly increased antioxidant levels in all cell models. This reflects that oxidative stress is reduced on the counterpart of increased antioxidant levels. This might be due to the activation of the AKT signaling pathway as evidenced by the increased AKT signals via western blotting and immunofluorescence. This data suggests that PBM promotes wound healing by increasing antioxidant levels by activating AKT signaling.

Transplantation of photobiomodulation-preconditioned diabetic stem cells accelerates ischemic wound healing in diabetic rats

BACKGROUND

Diabetic foot ulcer is the most costly and complex challenge for patients with diabetes. We hereby assessed the effectiveness of different preconditioned adipose-derived mesenchymal stem cells (AD-MSCs) and photobiomodulation protocols on treating an infected ischemic wound in type 1 diabetic rats.

METHODS

There were five groups of rats: (1) control, (2) control AD-MSCs [diabetic AD-MSCs were transplanted (grafted) into the wound bed], (3) AD-MSC + photobiomodulation in vivo (diabetic AD-MSCs were grafted into the wound, followed by in vivo PBM treatment), (4) AD-MSCs + photobiomodulation in vitro, and (5) AD-MSCs + photobiomodulation in vitro + in vivo.

RESULTS

Diabetic AD-MSCs preconditioned with photobiomodulation had significantly risen cell function compared to diabetic AD-MSC. Groups 3 and 5 had significantly decreased microbial flora correlated to groups 1 and 2 (all, p = 0.000). Groups 2, 3, 4, and 5 had significantly improved wound closure rate (0.4, 0.4, 0.4, and 0.8, respectively) compared to group 1 (0.2). Groups 2-5 had significantly increased wound strength compared to group 1 (all p = 0.000). In most cases, group 5 had significantly better results than groups 2, 3, and 4.

CONCLUSIONS

Preconditioning diabetic AD-MSCs with photobiomodulation in vitro plus photobiomodulation in vivo significantly hastened healing in the diabetic rat model of an ischemic infected delayed healing wound.

Engraftment of bioengineered three-dimensional scaffold from human amniotic membrane-derived extracellular matrix accelerates ischemic diabetic wound healing

Human amniotic membrane (HAM) is traditionally used for the treatment of non-healing wounds. However, high density of HAM-matrix (HAM-M) diminishes cellular contribution for successful tissue regeneration. Herein we investigated whether a bioengineered micro-porous three-dimensional (3D) HAM-scaffold (HAM-S) could promote healing in ischemic wounds in diabetic type 1 rat. HAM-S was prepared from freshly decellularized HAM. Then, 30 days after inducing diabetes, an ischemic circular excision was generated on rats' skin. The diabetic animals were randomly divided into untreated (Diabetic group), engrafted with HAM-M (D-HAM-M group) and HAM-S (D-HAM-S group). Also, non-diabeticuntreated rats (Healthy group) were considered as control. Stereological, molecular, and tensiometrical assessments were performed on post-surgical days 7, 14, and 21. We found that the volumes of new epidermis and dermis, the numerical density of epidermal basal cells and fibroblasts, the length density of blood vessels, the numbers of proliferating cells and collagen deposition as well as biomechanical properties of healed wound were significantly higher in D-HAM-S group in most cases compared those of the diabetic group, or even in some cases compared to D-HAM-M group. Furthermore, in D-HAM-S group, the transcripts for genes contributing to regeneration (Tgf-β, bFgf and Vegf) upregulated more than those of D-HAM-M group, when compared to diabetic ones. Overall, the HAM-S had more impact on delayed wound healing process compared to traditional use of intact HAM. It is therefore suggested that the bioengineered three dimensional micro-porous HAM-S is more suitable for cells adhesion, penetration, and migration for contributing to wounded tissue regeneration.

Photobiomodulation therapy improves the growth factor and cytokine secretory profile in human type 2 diabetic fibroblasts

Impaired wound healing is a common complication of diabetes mellitus (DM) and the underlying mechanism of this impairment is still unclear. Fibroblast, as the main reconstructing cell, secretes some critical growth factors and cytokine contributing to wound healing. It is well known that DM alters the behavior of these cells and photobiomodulation therapy (PBMT) compensates some impairments in diabetic fibroblasts. Therefore, the aim of the present study was to demonstrate the impact of diabetes and the role of PBMT through low level laser irradiation on secretory profile of human diabetic fibroblasts. Primary human dermal fibroblasts from normal (HDFs) and diabetic (DHDFs) donors were harvested. For PBMT, the DHDFs were irradiated with a Helium-Neon laser at 632.8 nm wavelength and energy density of 0.5 J/cm², as laser treated group (LT-DHDFs). Next, some cellular behaviors and secretory profiling array for 60 growth factors/cytokines were investigated in LT-DHDFs and then compared with those of controls. The data showed that the PBMT could compensate such impairments occurred in DHDFs in terms of viability, proliferation, and migration. Furthermore, considering our novel findings, out of those 20 growth factors/cytokines involved in cell proliferation, immune system regulation, and cell-cell communication pathways, which significantly decreased in DHDF as compared with HDFs, the PBMT could compensate seven in LT-DHDFs as compared with DHDFs. The seven growth factor/cytokines, which are mainly involved in cell-cell communication, positive regulation of cell proliferation, and chemokine mediated pathway included BDNF, Eotaxin-3, FGF6, FGF7, Fractalkine, fit-3ligand, and GCP-2. Therefore, it is suggested that scrutinizing these differentially secreted molecules and the impaired pathways in DHDFs, in combination with those compensated in LT-DHDFs, could raise our knowledge to manage diabetic ulcer through a feasible and cost effective intervention, specifically PBMT.