Arnebin-1 accelerates normal and hydrocortisone-induced impaired wound healing

GC-MS Profiling, Pharmacological Predictions, Molecular Docking, and ADME Studies of Different Parts of Thymus Linearis against Multiple Target Proteins in Wound Healing

Thymus linearis from the Himalayan woodlands of Gilgit Baltistan, Pakistan, is a phytomedicine that has not been well-studied. Traditionally, it is recognized for its potential in treating conditions such as dermatitis, psoriasis, weight loss, and discomfort. The study investigates the wound-healing properties of methanolic extracts from the plant's stems, leaves, and roots. GC-MS disclosed cadaverine, dihydroxy-3,3-dimethyl-3-hydroxy-N-isopropylbutyramide, phthalic acid-di(2-propylpentyl)ester, and benzo[h]quinolone-2,4-dimethyl in stem along with betamethasone valerate, 17-pentatriacontene, 1,1-cyclobutanedicarboxmide, heptadecane-9-hexyl, cyclohexanol-2-methylene-3(1-methylethenyl) and pentacyclo[12.3.0.0(1,13).0(2,10).0(5,9)]hepatodecane-6-ol-15-one in leaf extracts and 2-myristynonyl pantetheine, 7,8-epoxylanostan-11-ol-3-acetoxy, heneicosane (1-(1-ethyl propyl)), 2-piperidinone-N-[4-bromobutyl] and 1-monolinoleoylglycerol trimethyl silyl ether in the root extract. The antioxidant activity was assessed using several assays including DPPH, bound iron %, ABTS, total flavonoid content, and total phenolic content. The methanolic stem extract (MSE) showed the highest antioxidant capacity compared to the leaf and root extracts. The stem extract demonstrated the highest wound-healing potential, followed by leaves and roots in albino mice. The findings were supported by computational analysis, which revealed that the binding interactions of phytochemicals from stem have more affinity than leaf and root with specific receptor sites. The in-silico analysis ascertains that dihydroxy-3,3-dimethyl-3-hydroxy-N-isopropylbutyramide from MSE is the most effective wound-healing agent. Moreover, ADME predictions demonstrated the drug-like properties of the hit compounds.

Immunomodulation of Macrophages in Diabetic Wound Individuals by Structurally Diverse Bioactive Phytochemicals

Diabetes-related ulcers and slow-healing wounds pose a significant health risk to individuals due to their uncertain causes. Mortality rates for diabetes foot ulcers (DFUs) range from 10% after 16 months to 24% after five years. The use of bioactive phytochemicals can play a key role in healing wounds in a predictable time. Recent literature has demonstrated that various natural substances, including flavonoids, saponins, phenolic compounds, and polysaccharides, play key roles at different stages of the wound-healing process through diverse mechanisms. These studies have categorized the compounds according to their characteristics, bioactivities, and modes of action. In this study, we evaluated the role of natural compounds derived from plant sources that have been shown to play a crucial role in immunomodulation. Macrophages are closely involved in immunomodulation within the wound microenvironment and are key players in efferocytosis, inflammation resolution, and tissue regeneration, all of which contribute to successful wound healing. Phytochemicals and their derivatives have shown capabilities in immune regulation, including macrophage migration, nitric oxide synthase inhibition, lymphocyte and T-cell stimulation, cytokine activation, natural killer cell enhancement, and the regulation of NF-κβ, TNF-α, and apoptosis. In this review, we have studied the role of phytochemicals in immunomodulation for the resolution of diabetic wound inflammation.

Effects of Naphthoquinones from the Roots of Onosma Armeniacum Klokov on Wound Healing

In Turkish folk medicine, the roots of Onosma armeniacum Klokov are used to heal wounds, burns, hemorrhoids, hoarseness, dyspnea, stomach ulcers, and abdominal aches. The objective was to evaluate the plant's ethnopharmacological applications using in vivo pharmacological experimental models. In vivo linear incision and circular excision the wound models were used to assess the wound healing activity along with histopathological investigation. The active component(s) were isolated and identified after being exposed to several chromatographic separation procedures on the primary extract. The n-hexane-dichloromethane mixture extract was subjected to chromatographic separation after the wound-healing activity was confirmed. Deoxyshikonin (1), β,β-dimethylacrylshikonin (2), α-methyl-n-butylshikonin (3), isovalerylshikonin (4), acetylshikonin (5), β-hydroxyisovalerylshikonin (6), and 5,8-O-dimethylacetylshikonin (7) were identified as the structures of the isolated compounds. The efficacy of O. armeniacum to heal wounds was investigated in this study. Shikonin derivatives were identified as the primary active components of the roots by bioassay-guided fractionation and isolation procedures.

Promising Phytoconstituents in Diabetes-related Wounds: Mechanistic Insights and Implications

BACKGROUND

The onset of diabetes mellitus (DM), a metabolic disorder characterized by high blood glucose levels and disrupted glucose metabolism, results in 20% of people with diabetes suffering from diabetes-related wounds worldwide. A minor wound, such as a cut or abrasion, can lead to infections and complications in diabetic patients. We must understand the mechanism/s contributing to this delayed wound healing to develop effective prevention strategies. The potential benefits of bioactive phytochemicals for diabetic wound healing have been reported in numerous studies.

METHOD

A bioactive compound may have multiple actions, including antioxidants, antiinflammatory, antimicrobial, and angiogenesis. Compounds derived from these plants have shown promising results in wound healing, inflammation reduction, collagen synthesis, and neovascularization improvement.

RESULTS

Consequently, this review provides an update to our understanding of how phytoconstituents promote wound healing in diabetics. A thorough literature review was conducted on diabetes, wound healing, and phytoconstituents for this study. Only English publications until June 2023 were included in the search, which used multiple search engines and the main keywords. Summing up, phytochemical-based interventions might improve the quality of life for diabetics by improving wound healing.

CONCLUSION

However, to fully understand the efficacy and safety of these phytochemicals in managing diabetic wounds, more research and clinical trials are needed.

Novel Biotherapeutics Targeting Biomolecular and Cellular Approaches in Diabetic Wound Healing

Wound healing responses play a major role in chronic inflammation, which affects millions of people around the world. One of the daunting tasks of creating a wound-healing drug is finding equilibrium in the inflammatory cascade. In this study, the molecular and cellular mechanisms to regulate wound healing are explained, and recent research is addressed that demonstrates the molecular and cellular events during diabetic wound healing. Moreover, a range of factors or agents that facilitate wound healing have also been investigated as possible targets for successful treatment. It also summarises the various advances in research findings that have revealed promising molecular targets in the fields of therapy and diagnosis of cellular physiology and pathology of wound healing, such as neuropeptides, substance P, T cell immune response cDNA 7, miRNA, and treprostinil growth factors such as fibroblast growth factor, including thymosin beta 4, and immunomodulators as major therapeutic targets.

Review of Shikonin and Derivatives: Isolation, Chemistry, Biosynthesis, Pharmacology and Toxicology

Shikonin and its derivatives, isolated from traditional medicinal plant species of the genus Lithospermum, Alkanna, Arnebia, Anchusa, Onosma, and Echium belonging to the Boraginaceae family, have numerous applications in foods, cosmetics, and textiles. Shikonin, a potent bioactive red pigment, has been used in traditional medicinal systems to cure various ailments and is well known for its diverse pharmacological potential such as anticancer, antithrombotic, neuroprotective, antidiabetic, antiviral, anti-inflammatory, anti-gonadotropic, antioxidants, antimicrobial and insecticidal. Herein, updated research on the natural sources, pharmacology, toxicity studies, and various patents filed worldwide related to shikonin and approaches to shikonin’s biogenic and chemical synthesis are reviewed. Furthermore, recent studies to establish reliable production systems to meet market demand, functional identification, and future clinical development of shikonin and its derivatives against various diseases are presented.

Hybrid PCL/chitosan-PEO nanofibrous scaffolds incorporated with A. euchroma extract for skin tissue engineering application

Skin tissue engineering is an advanced method to repair and regenerate skin injuries. Recent research is focused on the development of scaffolds that are safe, bioactive, and cytocompatible. In this work, a new hybrid nanofibrous scaffold composed of polycaprolactone/chitosan-polyethylene oxide (PCL/Cs-PEO) incorporated with Arnebia euchroma (A. euchroma) extract were synthesized by the two-nozzle electrospinning method. Then the synthesized scaffold was characterized for morphology, sustainability, chemical structure and properties. Moreover, to verify their potential in the burn wound healing process, biodegradation rate, contact angle, swelling properties, water vapor permeability, mechanical properties, antibacterial activity and drug release profile were measured. Furthermore, cytotoxicity and biocompatibility tests were performed on human dermal fibroblasts cell line via XTT and LDH assay. It is shown that the scaffold improved and increased proliferation during in-vitro studies. Thus, results confirm the efficacy and potential of the hybrid nanofibrous scaffold for skin tissue engineering.

Perspective on the application of medicinal plants and natural products in wound healing: A mechanistic review

Wound is defined as any injury to the body such as damage to the epidermis of the skin and disturbance to its normal anatomy and function. Since ancient times, the importance of wound healing has been recognized, and many efforts have been made to develop novel wound dressings made of the best material for rapid and effective wound healing. Medicinal plants play a great role in the wound healing process. In recent decades, many studies have focused on the development of novel wound dressings that incorporate medicinal plant extracts or their purified active compounds, which are potential alternatives to conventional wound dressings. Several studies have also investigated the mechanism of action of various herbal medicines in wound healing process. This paper attempts to highlight and review the mechanistic perspective of wound healing mediated by plant-based natural products. The findings showed that herbal medicines act through multiple mechanisms and are involved in various stages of wound healing. Some herbal medicines increase the expression of vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β) which play important role in stimulation of re-epithelialization, angiogenesis, formation of granulation tissue, and collagen fiber deposition. Some other wound dressing containing herbal medicines act as inhibitor of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) protein expression thereby inducing antioxidant and anti-inflammatory properties in various phases of the wound healing process. Besides the growing public interest in traditional and alternative medicine, the use of herbal medicine and natural products for wound healing has many advantages over conventional medicines, including greater effectiveness due to diverse mechanisms of action, antibacterial activity, and safety in long-term wound dressing usage.

β-acetoxyisovaleryl alkannin (AAN-II) from Alkanna tinctoria promotes the healing of pressure-induced venous ulcers in a rabbit model through the activation of TGF-β/Smad3 signaling

Alkannin-based pharmaceutical formulations for improving wound healing have been on the market for several years. However, detailed molecular mechanisms of their action have yet to be elucidated. Here, we investigated the potential roles of AAN-II in improving the healing of pressure-induced venous ulcers using a rabbit model generated by combining deep vein thrombosis with a local skin defect/local skin defect. The extent of healing was evaluated using hematoxylin and eosin (HE) or vimentin staining. Rabbit skin fibroblasts were cultured for AAN-II treatment or TGFB1-sgRNA lentivirus transfection. ELISA was used to evaluate the levels of various cytokines, including IL-1β, IL-4, IL-6, TNF-α, VEGF, bFGF, TGF-β and PDGF. The protein levels of TGF-β sensors, including TGF-β, Smad7 and phosphor-Smad3, and total Smad3, were assayed via western blotting after TGF-β knockout or AAN-II treatment. The results show that, for this model, AAN-II facilitates ulcer healing by suppressing the development of inflammation and promoting fibroblast proliferation and secretion of proangiogenic factors. AAN-II enhances the activation of the TGF-β1-Smad3 signaling pathway during skin ulcer healing. In addition, the results demonstrate that AAN-II and TGF-β have synergistic effects on ulcer healing. Our findings indicate that AAN-II can promote healing of pressure-induced venous skin ulcers via activation of TGF-β-Smad3 signaling in fibroblast cells and provide evidence that could be used in the development of more effective treatments.

Molecular Concept of Diabetic Wound Healing: Effective Role of Herbal Remedies

The incidence of diabetes mellitus (DM) is on the rise, worldwide. One of the main complications in DM is delayed wound healing and it often requires amputation. Various drugs were used to treat DM but they presented with adverse effects. Often, patients failed to comply with such treatment. This opened the door for complementary and alternative medicine. In the present review, we explored the molecular concept of wound healing occurring in different stages with special emphasis to DM. We also highlighted the potential herbal products such as NF3 (Chinese 2-Herb Formula), Zicao, Jing Wan Hong ointment, Aleo vera, mixture of Adiantum capillus-veneris, Commiphora molmol, Aloe vera, and henna, Phenol-rich compound sweet gel, Jinchuang ointment, San-huang-sheng-fu (S) oil, Yi Bu A Jie extract, Astragali Radix (AR) and Rehmanniae Radix (RR), Yiqi Huayu, Tangzu yuyang ointment, Shengji Huayu recipe, Angelica sinensis, Lithospermun erythrorhison, Hippophae rhamnoides L., Curcuma longa and Momordica charantia that could be used effectively to treat DM wounds. Future clinical trials are needed for designing potential drugs which may be effective in treating DM wounds.

Synthesis of newly functionalized 1,4-naphthoquinone derivatives and their effects on wound healing in alloxan-induced diabetic mice

Naphthoquinone derivatives have various pharmacological properties. Here, we describe the synthesis of new 1,4-naphthoquinone derivatives inspired by lawsone and β-lapachone and their effects on both migration of fibroblasts in vitro and dermal wound healing in diabetic mice. NMR and FTIR spectroscopy aided characterization of chemical composition and demonstrated the molecular variations after the synthesis of four different derivatives, namely 2-bromo-1,4-naphthoquinone (termed derivative S3), 2-N-phenylamino-1,4-naphthoquinone (derivative S5), 2-N-isonicotinoyl-hydrazide-1,4-naphthoquinone (derivative S6), and 1-N-isonicotinoyl-hydrazone-[2-hydroxy-3-(3-methyl-2-butenyl)]-1,4-naphthoquinone (derivative S7). Our results indicate that derivatives S3, S5, S6 and S7 were non-toxic to the 3T3 fibroblast cell line. In scratch assays, derivatives S3 and S6, but not S5 or S7, stimulated the migration of fibroblasts. Compared with untreated diabetic mice, S3, S6 and S7 treatments accelerated wound closure. However, derivative S3 was optimal for the stimulation of epithelization, thereby increasing the number of keratinocyte layers and blood vessels, and reducing diffuse cellular infiltration, compared to derivatives S6 and S7. Our results suggest that novel 1,4-naphthoquinone derivatives promote fibroblast migration and accelerate wound closure under diabetic conditions.

Upregulation of MicroRNA-4262 Targets Kaiso (ZBTB33) to Inhibit the Proliferation and EMT of Cervical Cancer Cells

More and more studies have reported that dysregulation of microRNAs (miRNAs) leads to the proliferation and EMT of multiple cancers. Recently, several reports have demonstrated that dysregulation of miR-4262 occurs in numerous cancers. However, its role and precise mechanism in human cervical cancer (CC) have not been well clarified. Hence, this study aimed to explore the biological roles and precise mechanisms of miR-4262 in CC cell lines. The level of miR-4262 was found to be significantly decreased in CC tissues and cell lines. Moreover, decreased expression of miR-4262 was closely related to increased expression of Kaiso (ZBTB33), which belongs to the BTB/POZ family, in CC tissues and cell lines. The proliferation and EMT of CC cells were inhibited by a miR-4262 mimic. However, downregulation of miR-4262 enhanced the proliferation and EMT of CC cells. Next, bioinformatics analysis predicted that miR-4262 might directly target the Kaiso gene. Besides, luciferase reporter assay had confirmed this result. Moreover, introduction of Kaiso in CC cells partially blocked the effects of miR-4262 mimic. In conclusion, miR-4262 suppressed the proliferation and EMT of CC cells by directly downregulating Kaiso.

Anti-inflammatory properties of shikonin contribute to improved early-stage diabetic retinopathy

Diabetic retinopathy (DR), a major microvascular complication of diabetes, leads to retinal vascular leakage, neuronal dysfunction, and apoptosis within the retina. In this study, we combined STZ with whole-body hypoxia (10% O₂) for quicker induction of early-stage retinopathy in C57BL/6 mice. We also compared the effects of a high glucose condition combined with hypoxia (1% O₂) to a low glucose condition by using retinal pigment epithelial (RPE) cells, which are a crucial component of the outer blood-retinal barrier and the damage is related to retinopathy. In the retina of DM/hypoxic C57BL/6 mice, abnormal a-wave and b-wave activity, yellowish-white spots, hyperfluorescence, and reduced retinal thickness were found using electroretinography (ERG), fundus photography (FP), fundus fluorescein angiography (FFA), and optical coherence tomography (OCT). Shikonin dose-dependently (0.5–50 mg/kg, per os) prevented DM/hypoxia-induced lesions. In eye tissue, administration of shikonin also attenuated DM/hypoxia-induced pre-apoptotic protein BAX expression as well as the production of inflammatory proteins cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). We also demonstrated that shikonin administration rescues high glucose/hypoxia (1% O₂)-induced inflammation, decreased junction protein expression, and permeability in RPE cells. These results indicate that shikonin treatment may prevent the loss of vision associated with DR.

Effect of Topical Administration of Fractions and Isolated Molecules from Plant Extracts on Skin Wound Healing: A Systematic Review of Murine Experimental Models

Background and Purpose. Skin wound healing is a dynamic process driven by molecular events responsible for the morphofunctional repair of the injured tissue. In a systematic review, we analyzed the relevance of plant fractions and isolates on skin wound healing. By revising preclinical investigations with murine models, we investigated if the current evidence could support clinical trials. Methods. Studies were selected in the MEDLINE/PubMed and Scopus databases according to the PRISMA statement. All 32 identified studies were submitted to data extraction and the methodological bias was investigated according to ARRIVE strategy. Results. The studies demonstrated that plant fractions and isolates are able to modulate the inflammatory process during skin wound healing, being also effective in attenuating the oxidative tissue damage in the scar tissue and stimulating cell proliferation, neoangiogenesis, collagen synthesis, granulation tissue expansion, reepithelialization, and the wound closure rate. However, we identified serious methodological flaws in all studies, such as the high level of reporting bias and absence of standardized experimental designs, analytical methods, and outcome measures. Conclusion. Considering these limitations, the current evidence generated from flawed methodological animal studies makes it difficult to determine the relevance of herbal medicines to treat skin wounds and derails conducting clinical studies.

MicroRNA-124 upregulation inhibits proliferation and invasion of osteosarcoma cells by targeting sphingosine kinase 1

Increasing evidence has confirmed that the dysregulation of microRNAs (miRNAs) contributes to the proliferation and invasion of human cancers. Previous studies have shown that the dysregulation of miR-124 is in numerous cancers. However, the roles of miR-124 in human osteosarcoma (OS) have not been well clarified. Therefore, this study was to investigate the biological functions and molecular mechanisms of miR-124 in OS cell lines, discussing whether it could be a therapeutic biomarker of OS in the future. In this study, our results demonstrated that miR-124 was down-regulated in OS cell lines and tissues. Furthermore, the low level of miR-124 was associated with increased expression of Sphingosine kinase 1 (SPHK1) in OS cells and tissues. Up-regulation of miR-124 significantly inhibited cell proliferation, invasion, and MMP-2 and -9 expressions of OS cells. Bioinformatics analysis predicted that the SPHK1 was a potential target of miR-124. Further study by luciferase reporter assay demonstrated that miR-124 could directly target SPHK1. Overexpression of SPHK1 in OS cells transfected with miR-124 mimic partially reversed the inhibitory of miR-124. In conclusion, miR-124 inhibited cell proliferation and invasion in OS cells by downregulation of SPHK1, and that downregulation of SPHK1 was essential for the miR-124-inhibited cell invasion and in OS cells.

Glucose uptake stimulatory potential and antidiabetic activity of the Arnebin-1 from Arnabia nobelis

The enhanced disposal of glucose by the peripheral tissue is an important mechanism to regulate hyperglycemia. Here, we investigated the effect of Arnebin-1 from Arnebia nobilis, on glucose disposal in skeletal muscle cells and explored its in vivo antihyperglycemic potential. In L6 myotubes, Arnebin-1 stimulated glucose uptake, mediated through the enhanced translocation of the glucose transporter-4 (GLUT4) to plasma membrane, without changing the amount of GLUT4 or GLUT1. These effects of Arnebin-1 were synergistic with that of insulin. The effect of Arnebin-1 on glucose uptake was abolished in presence of wortmannin, and Arnebin-1 significantly stimulated the phosphorylation of Akt and downstream marker GSK-3β. Moreover, treatment with Arnebin-1 lowered postprandial blood glucose levels in streptozotocin-induced diabetic rats, and improved glucose tolerance and suppressed the rises in the fasting blood glucose, serum insulin, triglycerides, and total cholesterol in db/db mice, associated with enhanced expression of the major marker of the PI-3-Kinase-mediated signaling cascade in skeletal muscle. These findings suggest that Arnebin-1 exert antihyperglycemic activity through stimulating glucose disposal in peripheral tissues via PI-3-Kinase-dependent pathway.

Bioassay-guided isolation of wound healing active compounds from Echium species growing in Turkey

ETHNOPHARMACOLOGICAL RELEVANCE

The roots and root barks of Echium sp. have been used to treat ulcers, burns and wounds in traditional Turkish medicine.

AIM OF THE STUDY

On the basis of them traditional use and literature references, four Echium species were selected for evaluation of them wound healing potential. Isolation of active component(s) from the active extracts through the bioassay guided fractionation procedures.

MATERIAL AND METHODS

In vivo the wound healing activity of the plants was evaluated by linear incision experimental models. The chloroform extract of Echium italicum L. was fractionated by successive chromatographic techniques. Wound healing activity of each fraction was investigated following the bioassay-guided fractionation procedures. Moreover, the tissue samples of isolated compounds were examined histopathologically. The healing potential was comparatively assessed with a reference ointment Madecassol®, which contains 1% extract of Centella asiatica.

RESULTS

Significant wound healing activity was observed from the ointment prepared with ethanol extract at 1% concentration. The ethanol root extract treated in groups of animals showed a significant increase (37.38%, 40.97% and 35.29% separately for E. italicum L, Echium vulgare L. and Echium angustifolium Miller) wound tensile strength in the incision wound model. Subfractions showed significant but reduced wound healing activity on in vivo wound models. Shikonin derivatives "Acetylshikonin", "Deoxyshikonin" and "2-methyl-n-butyrylshikonin+Isovalerylshikonin", were isolated and determined as active components of active final subfraction from E. italicum L. roots. The results of histopathological examination supported the outcome of linear incision wound models.

CONCLUSION

The experimental study revealed that Echium species display remarkable wound healing activity.

Phytochemicals in Wound Healing

Significance: Traditional therapies, including the use of dietary components for wound healing and skin regeneration, are very common in Asian countries such as China and India. The increasing evidence of health-protective benefits of phytochemicals, components derived from plants is generating a lot of interest, warranting further scientific evaluation and mechanistic studies. Recent Advances: Phytochemicals are non-nutritive substances present in plants, and some of them have the potential to provide better tissue remodeling when applied on wounds and to also act as proangiogenic agents during wound healing. Critical Issues: In this review, we briefly discuss the current understanding, important molecular targets, and mechanism of action(s) of some of the phytochemicals such as curcumin, picroliv, and arnebin-1. We also broadly review the multiple pathways that these phytochemicals regulate to enhance wound repair and skin regeneration. Future Directions: Recent experimental data on the effects of phytochemicals on wound healing and skin regeneration establish the potential clinical utility of plant-based compounds. Additional research in order to better understand the exact mechanism and potential targets of phytochemicals in skin regeneration is needed. Human studies a2nd clinical trials are pivotal to fully understand the benefits of phytochemicals in wound healing and skin regeneration.

Arnebin-1 promotes angiogenesis by inducing eNOS, VEGF and HIF-1α expression through the PI3K-dependent pathway

Arnebin-1, a naphthoquinone derivative, plays a crucial role in the wound healing properties of Zicao (a traditional wound healing herbal medicine). It has been noted that Arnebin-1, in conjunction with vascular endothelial growth factor (VEGF), exerts a synergistic pro-angiogenic effect on human umbilical vein endothelial cells (HUVECs) and accelerates the healing process of diabetic wounds. However, the mechanisms responsible for the pro-angiogenic effect of arnebin-1 on HUVECs and its healing effect on diabetic wounds have not yet been fully elucidated. In this study, in an aim to elucidate these mechanisms of action of arnebin-1, we investigated the effects of arnebin-1 on the VEGF receptor 2 (VEGFR2) and the phosphoinositide 3-kinase (PI3K)-dependent signaling pathways in HUVECs treated with VEGF by western blot analysis. The pro-angiogenic effects of arnebin-1 on HUVECs, including its effects on proliferation and migration, were evaluated by MTT assay, Transwell assay and tube formation assay in vitro. The expression levels of hypoxia-inducible factor (HIF)-1α, endothelial nitric oxide synthase (eNOS) and VEGF were determined by western blot analysis in the HUVECs and wound tissues obtained from non-diabetic and diabetic rats. CD31 expression in the rat wounds was evaluated by immunofluorescence staining. We found that the activation of the VEGFR2 signaling pathway induced by VEGF was enhanced by arnebin-1. Arnebin-1 promoted endothelial cell proliferation, migration and tube formation through the PI3K-dependent pathway. Moreover, Arnebin-1 significantly increased the eNOS, VEGF and HIF-1α expression levels in the HUVECs and accelerated the healing of diabetic wounds through the PI3K-dependent signaling pathway. CD31 expression was markedly enhanced in the wounds of diabetic rats treated with arnebin-1 compared to the wounds of untreated diabetic rats. Therefore, the findings of the present study indicate that arnebin-1 promotes the wound healing process in diabetic rats by eliciting a pro-angiogenic response.

Anti-skin ageing activity of napthoquinones from Arnebia nobilis Reichb.f

The present isolation and identification of napthoquinones from roots of Arnebia nobilis Reichb.f. can lead to the discovery of new anti-skin ageing ingredient in colour cosmetics. Four compounds have been isolated and purified by rigorous column chromatography. The compounds are identified as β, β-dimethylacryl alkannin (AN-I), acetoxyisovaleryl alkannin (AAN-II), acetyl alkannin (AN-III) and alkannin (AN-IV) by interpretation of spectroscopic data. This study is the first to report the isolation of Acetoxyisovaleryl alkannin (AAN-II) from A. nobilis. The IC50 values of the compounds, determined in human skin cells (human dermal fibroblasts and human keratinocytes) and mouse embryonic fibroblasts (NIH3T3) varied significantly among the four alkannins. Among the four compounds, β-acetoxyisovaleryl alkannin (AAN-II) significantly inhibited hydrogen peroxide (H2O2)-induced red blood corpuscle haemolysis and cellular senescence in human dermal fibroblasts. Collagen-I, elastin and involucrin syntheses in human dermal fibroblasts or keratinocytes were up regulated by AAN-II. These results support the potential utility of alkannins as novel anti-ageing ingredients.

Arnebin-1 promotes the angiogenesis of human umbilical vein endothelial cells and accelerates the wound healing process in diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Zicao is a traditional wound healing herbal medicine that has been used for several hundred years in China. A survey of the published literatures revealed that arnebin-1, one of the naphthoquinone derivatives, played the most important role in wound healing property of this plant. However, whether arnebin-1 affects angiogenesis in vitro and has an effect on wound healing process in diabetic rats remains enigmatic. To investigate the effect of arnebin-1 with or without VEGF on proliferation, migration and tube formation of HUVECs in vitro and the effect of its topical application in the form of ointment on wound healing in a cutaneous punch wound model of alloxan-induced diabetic rats in vivo.

MATERIALS AND METHODS

The pro-angiogenic functions of arnebin-1 on HUVECs including proliferation, migration and angiogenesis were evaluated through MTT assay, wound healing assay, transwell assay and tube formation assay in vitro. Male Sprague-Dawley rats were injected intraperitoneally with alloxan to induce type І diabetic rats. Three wounds were created in each rat on the dorsal surface, and then divided to be basement treated, arnebin-1 ointment treated and untreated group correspondingly. The indicators including wound closure rate and histological evaluation were investigated on day 4 and 7 post-wounding.

RESULTS

Without VEGF, arnebin-1 did not affect the proliferation of HUVECs significantly, but had a positive effect on cell migration and tube formation. However, in the presence of minimal VEGF, Arnebin-1 could increase the proliferation, enhance the migration and promote the tube formation of HUVECs significantly. The wound closure rate was increased significantly in arnebin-1 treated group compared to that of untreated and basement treated groups in diabetic rats, and the histological evaluation also showed well organized dermal layer, reduced number of macrophages, increased number of fibroblasts, remarkable degree of neovascularization and epithelization in arnebin-1 treated group.

CONCLUSION

These findings suggest that arnebin-1 has a pro-angiogenic effect, and a synergetic effect with VEGF promotes the wound healing process in diabetic rats.

The effect of aloe vera oral administration on cutaneous wound healing in type 2 diabetic rats

Delayed wound healing is one of the complications of diabetes mellitus. The present study was performed to investigate the effect of Aloe vera oral administration on open wounds in type 2 diabetic rats. Full thickness open wounds (1.5 × 1.5 cm) were created under general anesthesia on the backs of the rats. These rats were divided into two group, a control group (Group C) and an Aloe vera oral administration group (Group A). Each wound area was measured on days 1, 2, 4 and 8 postwounding. The stages of wound granulation tissues were evaluated histopathologically. The expression of transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF) were determined by immunohistochemically. The wounds were significantly contracted in Group A on days 2, 4 and 8 postwounding. Histological results revealed that the inflammatory cell infiltration, angiogenesis, extracellular matrix deposition and epithelialization were promoted in Group A, respectively. The immunohistochemical results revealed that both TGF-β1 and VEGF protein-positive cells increased in Group A on day 4 postwounding. We concluded that Aloe vera oral administration accelerated wound healing in type 2 diabetic rats.

Apoptosis quantification at the respiratory epithelium level in asthma

The „changes” occurring in the expression of the factors involved in the apoptotic chain at the level of the respiratory epithelium in asthma is still an unsolved issue. At this level an important role is played by the mitochondria and the factors that influence the membrane permeability, especially the Bcl-2 super family. The purpose of this study is to evaluate both the changes in the expression of the Bcl-2 and of the Bax proapoptotic factors at the respiratory epithelium level in 21 patients with bronchial asthma of different degrees of severity of disease (aaccording to GINA — Global Initiative For Asthma). To accomplish this, fragments of the bronchial mucosa were obtained through fiberbronchoscopy, being afterwords hystologically prepare in view of the immunomarking with anti Bcl-2 and anti-Bax antibodies. Microscopic examination revealed an important decrease in the level of proapoptotic factor Bcl-2 in patients with persistent severe forms of the disease and a significant decrease in the expression of the proapototic Bax factor at the respiratory epithelium level even in the early stages of the disease. Knowing all the factors involved in apoptosis at the respiratory epithelium level in bronchial asthma, as well as of their expression changes will be at the core of new therapeutical approaches to of this disease.

Androstenediol reverses steroid-inhibited wound healing

It is well recognized that stress of any nature will cause a delay in the wound healing response. This delayed healing response appears closely associated with immune regulators. In this study, CD-1 mice were injected with a long acting form of methyl prednisolone to cause a steroid-induced immune suppression. After 24 hours, two 6-mm full thickness wounds were placed on the animals' backs and one group of animals received the immune-regulating hormone, androstenediol. Wound contraction was quantified by planimetry for the subsequent 14 days. Animals that were stressed with methyl prednisolone but receiving androstenediol contracted their open wounds at faster rates compared with methyl prednisolone-stressed animals treated with the vehicle alone. These findings suggest that restoration of immune regulation by androstenediol can reverse the delayed open wound contraction secondary to steroid stress.

Exploring the wound healing activity of Arnebia densiflora (Nordm.) Ledeb. by in vivo models

ETHNOPHARMACOLOGICAL RELEVANCE

The roots of Arnebia densiflora (Nordm.) Ledeb. (Boraginaceae), which is an endemic plant for Turkey, have been used for healing of wounds in folk medicine. The extract of the roots in olive oil and mostly the root barks was applied onto open wounds for rapid healing.

AIM OF THE STUDY

To evaluate the wound healing activity of the roots, extracts were prepared with different solvents; hexane, chloroform, ethyl acetate and methanol, respectively from the roots of Arnebia densiflora.

MATERIALS AND METHODS

Incision by using tensiometer and excision models were employed on mice and rats.

RESULTS

Significant wound healing activity was observed with the ointment formulation prepared by using hexane extract at 1% concentration on the mentioned models. The results of histopathological examination supported the outcome of both incision and excision wound models. The wound healing effect was comparatively evaluated with a reference ointment Madecassol.

CONCLUSION

The experimental data demonstrated that Arnebia densiflora displayed remarkable wound healing activity.

Fibroblast growth stimulation by extracts and compounds of Onosma argentatum roots

The roots of Onosma argentatum are used traditionally in Turkey for wound healing and burns. The n-hexane-dichloromethane extract of the roots, and four shikonin derivatives (deoxyshikonin, acetyl shikonin, 3-hydroxy-isovaleryl shikonin and 5,8-O-dimethyl acetyl shikonin) isolated from the n-hexane-dichloromethane extract were investigated for their ability to stimulate the growth of human amnion fibroblasts. A range of concentrations was studied and the extract found to stimulate the growth of human amnion fibroblasts in vitro at 0.1 microg/mL whilst 5,8-O-dimethyl acetyl shikonin had the same effect at 0.05-5 microg/mL, although cytotoxicity was observed at 50 microg/mL for all samples. The extract and all the other isolated compounds showed cytotoxicity at 10 microg/mL with the extract and 3-hydroxy-isovaleryl shikonin showing cytotoxicity at 5 microg/mL. It is suggested that any wound healing effect of the roots of Onosma argentatum might be partly due to an additive effect of the shikonin derivatives present.

Pexiganan-incorporated collagen matrices for infected wound-healing processes in rat

The use of peptide-based drugs is limited by their rapid degradability and toxicity at high concentration during their therapeutic application. These problems could be managed by the use of a peptide delivery agent for sustained release in the site of action. Collagen is one of the most proven biomaterials of good biocompatibility with an exceptional ligand encapsulating property. In this work, we have shown that pexiganan, an antimicrobial, 22-amino-acid peptide could be incorporated and delivered to the wound-healing site against bacterial strains Pseudomonas aeruginosa and Staphylococcus aureus. The release profiles of pexiganan collagen films with different collagen concentration were studied. The release of pexiganan from 2.5% w/w of collagen film showed a sustainable activity over 72 h with effective antimicrobial concentrations. Pexiganan-incorporated collagen (PIC)-treated groups were compared with open wound (OW)- and collagen film (CF)-treated rats. PIC-treated animals showed a diminishing level of bacterial growth as compared with OW- and CF-treated animals. The biochemical parameters such as hydroxyproline, protein, DNA, uronic acid, hexosamine, SOD, and catalase content in the granulation tissue of the healing wound revealed increased proliferation of cells involved in tissue reconstruction in PIC-treated groups when compared with OW- and CF-treated groups. Furthermore, spectroscopic studies suggested that collagen structure is not perturbed by pexiganan incorporation. This study provides rationale for application of collagen membrane for antimicrobial peptide delivery in infected wounds.

Biotinylated GHK peptide incorporated collagenous matrix: A novel biomaterial for dermal wound healing in rats

Matrikines are small peptide fragments of extracellular matrix proteins that display potent tissue repair activities. Difficulties in achieving sustained delivery of bioactive concentration of matrikines in the affected area limits their therapeutic use. The present study evaluates the effects biotinylated matrikine peptide (bio-glycyl-histidyl-lysine) incorporated collagen membrane for dermal wound healing processes in rats. Biotinylated peptide incorporated collagen matrix (PIC) showed better healing when compared to wounds treated with collagen matrix [CF (collagen film)] and without collagen [CR (control)]. Binding studies indicate that biotinylated GHK (Bio-GHK) binds effectively to the collagen matrix and red blood cell (RBC) membrane when compared with t-butyloxycarbonyl substituted GHK (Boc-GHK). Wound contraction, increased cell proliferation, and high expression of antioxidant enzymes in PIC treated group indicate enhanced wound healing activity when compared to CF and CR groups. Interestingly Bio-GHK incorporated collagen increases the copper concentration by ninefold at the wound site indicating the wound healing property of Bio-GHK can also be linked with both copper localization and matrikine activities. These results demonstrate the possibility of using Bio-GHK incorporated collagen film as a therapeutic agent in the wound healing process.

Alpha-crystallin-incorporated collagen matrices as an aid for dermal wound healing

This study evaluated the effects of noncovalently incorporated crystallin into the collagen matrix for dermal wound-healing processes in rats. Crystallin-incorporated collagen matrix (CIC) showed better healing when compared to wounds treated with collagen matrix (CS) and without collagen (CR). Biochemical parameters and histological analysis revealed that increased wound contraction enhanced cell proliferation and efficient radical scavenging in the CIC group. The higher shrinkage temperature of CIC films when compared to CS groups suggested increased hydrothermal stability for the former material. An in vitro release study of CIC has showed sustained and time-dependent release of crystallin from the collagen matrix. These results demonstrate the possibility of using crystallin as therapeutic protein in the wound-healing process.

Dermal wound healing processes with curcumin incorporated collagen films

The wound healing process involves extensive oxidative stress to the system, which generally inhibits tissue remodeling. In the present study, an improvement in the quality of wound healing was attempted by slow delivery of antioxidants like curcumin from collagen, which also acts as a supportive matrix for the regenerative tissue. Curcumin incorporated collagen matrix (CICM) treated groups were compared with control and collagen treated rats. Biochemical parameters and histological analysis revealed that increased wound reduction, enhanced cell proliferation and efficient free radical scavenging in CICM group. The higher shrinkage temperature of CICM films suggests increased hydrothermal stability when compared to normal collagen films. Spectroscopic studies revealed that curcumin was bound to the collagen without affecting its triple helicity. Further we adopted the antioxidant assay using 2,2'-azobisisobutyronitrile to assess in vitro antioxidant activity of CICM. The antioxidant studies indicated that CICM quenches free radicals more efficiently. This study provides a rationale for the topical application of CICM as a feasible and productive approach to support dermal wound healing.

Enhancement of wound healing by shikonin analogue 93/637 in normal and impaired healing

Wound healing is a complicated biological process, which involves interactions of multiple cell types, various growth factors, their mediators and the extracellular matrix proteins. In this study, we evaluated the effects of shikonin analogue 93/637 (SA), derived from the plant Arnebia nobilis, on normal and hydrocortisone-induced impaired healing in full thickness cutaneous punch wounds in rats. SA (0.1%) was applied topically daily as an ointment in polyethylene glycol base on wounds. SA treatment significantly accelerated healing of wounds, as measured by wound contraction compared to controls in hydrocortisone-impaired animals. SA treatment promoted formation of granulation tissue including cell migration and neovascularization, collagenization and reepithelialization. The expression of basic fibroblast growth factor (bFGF) was higher as revealed by immunohistochemistry in treated wounds compared to controls. However, the expression of transforming growth factor-beta(1) was not affected by SA treatment. Since bFGF is known to accelerate wound healing, the increased expression of bFGF by SA may be partly responsible for the enhancement of wound healing. These studies suggest that SA could be further studied for clinical use to enhance wound healing.

Corticosteroid-induced apoptosis of airway epithelium: a potential mechanism for chronic airway epithelial damage in asthma

Damage to the airway epithelium is one prominent feature of chronic asthma. Mucosal damage includes gap openings, partial denudation, and loss of ciliated cells. Apoptosis of the airway epithelium is increasingly recognized as a potential mechanism by which damage may occur. Corticosteroids (CSs) induce apoptosis in inflammatory cells, which in part explains their ability to suppress airway inflammation. However, CS therapy does not necessarily reverse epithelial damage. We examined whether CS therapy actually could induce airway epithelial apoptosis using culture models of primary airway epithelial cells and cell lines. The administration of CSs in low-micromolar concentrations induces apoptosis that involves the disruption of mitochondrial polarity, the activation of caspases, and the involvement of Bcl-2. Clear differences exist between CS-induced apoptosis in the cultured epithelium vs cultured hematopoietic cells in regard to time course and resistance to apoptosis. Our data suggest that the use of CSs, in concentrations that could be attained in vivo with the inhalation of potent preparations or with systemic administration, may be one factor in the airways remodeling and epithelial damage that is seen in many patients with chronic, persistent asthma.

Cellular pharmacology studies of shikonin derivatives

The naphthoquinone pigment, shikonin, isolated from Lithospermum erythrorhizon Sieb. et Zucc.(Boraginaceae) and its derivatives are the active components isolated from the Chinese herbal therapeutic, Zicao. Historically, Zicao root extracts have been used to treat macular eruption, measles, sore-throat, carbuncles and burns. Multiple pharmacological actions have been attributed to shikonin, e.g. antiinflammatory, antigonadotropic and anti-HIV-1 activity. In this review, several therapeutic applications of shikonin will be summarized including its pleiotropic, antiinflammatory and antitumour effects. Widely diverse and sometimes conflicting activities have been attributed to shikonin, e.g. wound healing, enhanced granuloma formation, suppression of local acute inflammatory reactions, inhibition of angiogenesis, inhibition of select chemokine ligands, inhibition of DNA topoisomerase activity, inhibition of platelet activation and antimicrobial activity. Comparison of the various reported mechanisms of action for shikonin lead us to hypothesize that shikonin is an effective inhibitor of protein-protein interaction with multiple targets in both the intracellular and extracellular compartments. This general inhibitory effect can account for the broad spectrum of shikonin biological and pharmacological activities.

Apoptosis of airway epithelial cells induced by corticosteroids

Damage to the airway epithelium is one prominent feature of chronic asthma. Corticosteroids induce apoptosis in inflammatory cells, which in part explains their ability to suppress airway inflammation. However, corticosteroid therapy does not necessarily reverse epithelial damage. We hypothesized that corticosteroids may induce airway epithelial cell apoptosis as one potential explanation for persistent damage. We tested this hypothesis in cultured primary central airway epithelial cells and in the cell line 1HAEo(-). Treatment with dexamethasone, beclomethasone, budesonide, or triamcinolone each elicited a time-dependent and concentration-dependent cell death. This cell death was associated with cleavage of nuclear chromatin, mitochondrial depolarization, cytochrome c extrusion, activation of caspase-9, and expression of phosphatidylserine on the outer cell membrane. Inhibitors of caspase activity blocked apoptotic cell death, as did overexpression of the apoptosis regulators Bcl-2 or Bcl-x(L). We demonstrated that CD95 ligation is not essential for the corticosteroid-induced apoptosis in airway epithelial cells. These data demonstrate that corticosteroids induce apoptotic cell death of airway epithelium. This raises the possibility that at least one of the major components of chronic airway damage in asthma, epithelial shedding and denudation, may in part result from a major therapy for the disease.

Lysine: Is it worth more?

Lysine, an essential cationic amino acid, has a positively charged R group. The structure of lysine is given as (H(3)N(+)-)CH(-COO(-))-CH(2)-CH(2)-CH(2)-CH(2)-N(+)H(3).While the anabolic role(s) of the molecule has been in focus for quite a few decades now, its biological properties, e.g. role in cellular proliferation in vitro (both anchorage dependent and anchorage independent) and in vivo, its ability to induce strong inflammatory and immune responses - both humoral and cell mediated, its role in augmented healing of all types of wounds in animal models as well as in human subjects (both acute and chronic), as well as its role in inducing extensive angiogenic responses, have never received reasonable attention so far. In the current brief and indicative review (rather than exhaustive reviews of each area), we intend to bring these biological properties of the molecule to focus while discussing a few other interesting aspects - lysine as a food preservative as well as its possible role(s) in immune therapy. While the areas look extremely divergent, we propose a common denominator in the form of a possible molecular mechanism of action of the molecule in all these diverse situations.