Cell-based regenerative strategies for treatment of diabetic skin wounds, a comparative study between human umbilical cord blood-mononuclear cells and calves' blood haemodialysate

Camptothecin structure simplification elaborated new imidazo[2,1-b]quinazoline derivative as a human topoisomerase I inhibitor with efficacy against bone cancer cells and colon adenocarcinoma

Camptothecin is a pentacyclic natural alkaloid that inhibits the hTop1 enzyme involved in DNA transcription and cancer cell growth. Camptothecin structure pitfalls prompted us to design new congeners using a structure simplification strategy to reduce the ring extension number from pentacyclic to tetracyclic while maintaining potential stacking of the new compounds with the DNA base pairs at the Top1-mediated cleavage complex and aqueous solubility, as well as minimizing compound-liver toxicity. The principal axis of this study was the verification of hTop1 inhibiting activity as a possible mechanism of action and the elaboration of new simplified inhibitors with improved pharmacodynamic and pharmacokinetic profiling using three structure panels (A-C) of (isoquinolinoimidazoquinazoline), (imidazoquinazoline), and (imidazoisoquinoline), respectively. DNA relaxation assay identified five compounds as hTop1 inhibitors belonging to the imidazoisoquinolines 3a,b, the imidazoquinazolines 12, and the isoquinolinoimidazoquinazolines 7a,b. In an MTT cytotoxicity assay against different cancer cell lines, compound 12 was the most potent against HOS bone cancer cells (IC50 = 1.47 μM). At the same time, the other inhibitors had no detectable activity against any cancer cell type. Compound (12) demonstrated great penetrating power in the HOS cancer cells' 3D-multicellular tumor spheroid model. Bioinformatics research of the hTop1 gene revealed that the TP53 cell proliferative gene is in the network of hTop1. The finding is confirmed empirically using the gene expression assay that proved the increase in p53 expression. The impact of structure simplification on compound 12 profile, characterized by the absence of acute oral liver toxicity when compared to Doxorubicin as a standard inhibitor, the lethal dose measured on Swiss Albino female mice and reported at LD50 = 250 mg/kg, and therapeutic significance in reducing colon adenocarcinoma tumor volume by 75.36 % after five weeks of treatment with compound 12. The molecular docking solutions of the active CPT-based derivative 12 and the inactive congener 14 into the active site of hTop1 and the activity cliffing of such MMP directed us to recommend the addition of HBD and HBA variables to compound 12 imidazoquinazoline core scaffold to enhance the potency via hydrogen bond formation with the major groove amino acids (Asp533, Lys532) as well as maintaining the hydrogen bond with the minor groove amino acid Arg364.

Acetaminophen-traces bioremediation with novel phenotypically and genotypically characterized 2 Streptomyces strains using chemo-informatics, in vivo, and in vitro experiments for cytotoxicity and biological activity

We isolated two novel bacterial strains, active against the environmental pollutant acetaminophen/Paracetamol®. Streptomyces chrestomyceticus (symbol RS2) and Flavofuscus (symbol M33) collected from El-Natrun Valley, Egypt-water, sediment, and sand samples, taxonomically characterized using a transmission electron microscope (TEM). Genotypic identification, based on 16S rRNA gene sequence analysis followed by BLAST alignment, were deposited on the NCBI as 2 novel strains https://www.ncbi.nlm.nih.gov/nuccore/OM665324  and https://www.ncbi.nlm.nih.gov/nuccore/OM665325 . The phylogenetic tree was constructed. Acetaminophen secondary or intermediate product's chemical structure was identified by GC/LC MS. Some selected acetaminophen secondary-product extracts and derived compounds were examined against a panel of test micro-organisms and fortunately showed a good anti-microbial effect. In silico chemo-informatics Swiss ADMET evaluation was used in the selected bio-degradation extracts for absorption (gastric), distribution (to CNS), metabolism (hepatic), excretion (renal), and finally not toxic, being non-mutagenic/teratogenic or genotoxic, virtually. Moreover, in vitro cytotoxic activity of these selected bio-degradation secondary products was examined against HepG2 and MCF7 cancer cell lines, where M33 and RS2 extract effects on acetaminophen/paracetamol bio-degradation products were safe, with higher IC50 on HepG2 and MCF7 than the acetaminophen/paracetamol IC50 of 108.5 μg/ml. Moreover, an in vivo oral acute single-dose toxicity experiment was conducted, to confirm these in vitro and in silico lower toxicity (better safety) than acetaminophen/paracetamol.

Overexpression of VEGF in dermal fibroblast cells accelerates the angiogenesis and wound healing function: in vitro and in vivo studies

Fibroblasts are the main cells of connective tissue and have pivotal roles in the proliferative and maturation phases of wound healing. These cells can secrete various cytokines, growth factors, and collagen. Vascular endothelial growth factor (VEGF) is a unique factor in the migration process of fibroblast cells through induces wound healing cascade components such as angiogenesis, collagen deposition, and epithelialization. This study aimed to create VEGF₁₆₅ overexpressing fibroblast cells to evaluate angiogenesis function in wound healing. In vitro, a novel recombinant expression vector, pcDNA3.1(-)-VEGF, was produced and transfected into the fibroblast cells. Following selecting fibroblast cells with hygromycin, recombinant cells were investigated in terms of VEGF expression by quantifying and qualifying methods. Mechanical, physical, and survival properties of polyurethane-cellulose acetate (PU-CA) scaffold were investigated. Finally, in vivo, the angiogenic potential was evaluated in four groups containing control, PU-CA, PU-CA with fibroblast cells, and VEGF-expressing cells on days 0, 2, 5, 12 and 15. Wound biopsies were harvested and the healing process was histopathologically evaluated on different days. qRT-PCR showed VEGF overexpression (sevenfold) in genetically-manipulated cells compared to fibroblast cells. Recombinant VEGF expression was also confirmed by western blotting. Manipulated fibroblast cells represented more angiogenesis than other groups on the second day after surgery, which was also confirmed by the antiCD31 antibody. The percentage of wound closure area on day 5 in genetically-manipulated Hu02 and Hu02 groups showed a significant reduction of wound area compared to other groups. These findings indicate that overexpression of VEGF₁₆₅ in fibroblast cells results in enhanced angiogenesis and formation of granulated tissue in the early stage of the healing process, which can show its therapeutic potential in patients with impaired wound healing and also provide functional support for gene therapy.

Topical Gynura procumbens as a Novel Therapeutic Improves Wound Healing in Diabetic Mice

Nonhealing wounds are major socioeconomic challenges to healthcare systems worldwide. Therefore, there is a substantially unmet need to develop new drugs for wound healing. Gynura procumbens, a herb found in Southeast Asia, may be an effective therapeutic for nonhealing diabetic wounds. The aim of this study was to evaluate the efficacy of G. procumbens on wound healing in the diabetic milieu. G. procumbens extract was obtained using 95% ethanol and its components were determined by thin layer chromatography. Diabetes was induced in mice using streptozotocin. We found that G. procumbens extract contained stigmasterol, kaempferol and quercetin compounds. Topical application of G. procumbens on the wounded skin of diabetic mice accelerated wound healing and induced the expression of angiogenin, epidermal growth factor, fibroblast growth factor, transforming growth factor and vascular endothelial growth factor. Furthermore, G. procumbens promoted in vitro wound healing and enhanced the migration and/or proliferation of human endothelial cells, fibroblasts, keratinocytes and mast cells cultured in diabetic conditions. Finally, G. procumbens promoted vascular formation in the diabetic mice. To the best of our knowledge, this is the first study that evaluates in vivo wound healing activities of G. procumbens and activation of cells involved in wound healing process in diabetic conditions. The findings that G. procumbens accelerates wound healing and activates cells involved in the wound healing process suggest that G. procumbens might be an effective alternative therapeutic option for nonhealing diabetic wounds.

Influence of Recombinant Codon-Optimized Plasmid DNA Encoding VEGF and FGF2 on Co-Induction of Angiogenesis

Simple Summary

Over the past few decades, several methods have been proposed to stimulate skin wound healing. The most promising of these are gene therapy and stem cell therapy. Our present experiments have combined several approaches utilizing human umbilical cord blood mononuclear cells using cell therapy, and direct gene therapy using genetic constructs to accelerate complete healing of skin wounds in rats. Studies have shown that the transplantation of transfected cells stopped proliferative processes in regenerating wounds earlier than the transplantation of untransfected cells. The use of direct gene therapy using the VEGF and FGF2 genes stimulates the revascularization of the rat cutaneous wound.

Abstract

Several methods for the stimulation of skin wound repair have been proposed over the last few decades. The most promising among them are gene and stem cell therapy. Our present experiments combined several approaches via the application of human umbilical cord blood mononuclear cells (hUCB-MC) that were transfected with pBud-VEGF165-FGF2 plasmid (gene-cell therapy) and direct gene therapy using pBud-VEGF165-FGF2 plasmid to enhance healing of full thickness skin wounds in rats. The dual expression cassette plasmid pBud-VEGF165-FGF2 encodes both VEGF and FGF2 therapeutic genes, expressing pro-angiogenic growth factors. Our results showed that, with two weeks post-transplantation, some transplanted cells still retained expression of the stem cell and hematopoietic markers C-kit and CD34. Other transplanted cells were found among keratinocytes, hair follicle cells, endothelial cells, and in the derma. PCNA expression studies revealed that transplantation of transfected cells terminated proliferative processes in regenerating wounds earlier than transplantation of untransfected cells. In the direct gene therapy group, four days post-operatively, the processes of flap revascularization, while using Easy LDI Microcirculation Camera, was higher than in control wounded skin. We concluded that hUCB-MC can be used for the treatment of skin wounds and transfection these cells with VEGF and FGF2 genes enhances their regenerative abilities. We also concluded that the application of pBud-VEGF165-FGF2 plasmids is efficient for the direct gene therapy of skin wounds by stimulation of wound revascularization.

Investigating the efficacy and safety of mineral smectite granules on wound healing

Mineral smectite granules have traditionally been used for diarrhea and gastrointestinal bleeding; however, the wound healing ability of mineral smectite granules has not been investigated in detail. Therefore, the present study explored the efficacy and safety of mineral smectite granules on wound healing. An excision wound rat model was established. The experimental group was treated with smectite granules, the positive control group was treated with starch and the blank control group was left untreated. Wound closure rates, wound healing times and histopathological analysis were compared among the three groups. The mechanism underlying the effects of mineral smectite granules on wound healing was assessed by performing picrosirius red staining and immunohistochemical staining and measuring hydroxyproline content. Based on wound closure rates, wound healing times and histopathological analysis, the results indicated that rats treated with smectite granules displayed increased wound healing efficacy compared with the other two groups. Investigation of the underlying mechanism suggested that mineral smectite granules could promote wound healing by inducing collagen fiber synthesis and increasing the number of neovessels. The present study indicated the efficacy and safety of mineral smectite granules on wound healing and provided a theoretical basis for its application in a clinical setting.

Efficacy of stem cells on the healing of peri-implant defects: systematic review of preclinical studies

This systematic review considers the evidence from animal studies evaluating the effectiveness of mesenchymal stem cells (MSC) in the treatment of intraoral peri-implant defects. MEDLINE, EMBASE, and LILACS databases were searched for quantitative preclinical controlled animal model studies that evaluated the effect of MSC on bone healing at intraoral peri-implant bone defects. The primary outcome was the amount of (re-)osseointegration reported as bone-to-implant contact in the defect area. The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. Ten studies met the inclusion criteria. Only one study induced peri-implant inflammation to produce peri-implant bone defects. In all others, defects were surgically created at implant installation. Differences in defect morphology were identified among the studies. Both xenogenous and autogenous MSC were used to treat peri-implant defects. These included bone marrow-derived MSC, periodontal ligament-derived MSC, umbilical cord MSC, bone marrow-derived mononuclear cells, and peripheral blood mononuclear cells. Meta-analysis was not possible because of heterogeneities in study designs. Nonetheless, in most studies, local MSC implantation was not associated with adverse effects and had a positive effect on bone healing around peri-implant defects. Combination of MSC with membranes and bioactive factors appears to provide improved treatment outcomes. In large animal models, intraoral use of MSC may provide beneficial effects on bone healing within peri-implant defects. The various degrees of success of MSC in peri-implant bone healing are likely to be related to the use of cells from various populations, tissues, and donor species. However, human safety and efficacy must be demonstrated before its clinical use can be considered.

Topical application of Acheflan on rat skin injury accelerates wound healing: a histopathological, immunohistochemical and biochemical study

Background

Dermal wound healing involves a cascade of complex events including angiogenesis and extracellular matrix remodeling. Several groups have focused in the study of the skin wound healing activity of natural products. The phytomedicine Acheflan®, and its main active constituent is the oil from Cordia verbenacea which has known anti-inflammatory, analgesic and antimicrobial activities. To our knowledge, no investigation has evaluated the effect of Acheflan® in an experimental model of skin wound healing.

The present study has explored the wound healing property of Acheflan® and has compared it with topical effectiveness of collagenase and fibrinolysin by using Wistar rat cutaneous excision wound model.

Methods

Animals were divided into four groups: untreated animals are negative control (NC), wounds were treated topically every day with Collagenase ointment (TC), with Fibrinolysin ointment (TF) and with cream Acheflan (TAc). Skin samples were collected on zero, 8th and 15th days after wounding. The healing was assessed by hematoxylin-eosin (HE), picrosirius red, hydoxyproline content and immunohistochemical analysis of the vascular endothelial growth factor (VEGF) and matrix metalloprotease-9 (MMP-9). Statistical analysis was done by ANOVA and Student t-test (p < 0.05).

Results

The histological analysis HE of wound in the TAc group was more efficient because it was possible to observe the complete remodeling of the epidermis indicating the regression of lesions compared with the NC. The evaluation of picrosirius staining has demonstrated a significant increase of collagen distribution in the TC and TAc treatments compared with NC and TF groups. These results are corroborated with hydroxyproline content. Skin TC and TAc treated rats have showed an increase of VEGF and MMP-9 compared with NC and TF groups. All parameters were significant (P < 0.05).

Conclusion

The phytomedicine Acheflan® (oil of Cordia verbenacea) and TC possess higher therapeutic properties for wound healing compared with TF. These ointments seem to accelerate wound healing, probably due to their involvement with the increase of angiogenesis and dermal remodeling.