Wound healing activity of Delonix elata stem bark extract and its isolated constituent quercetin-3-rhamnopyranosyl-(1-6) glucopyranoside in rats

Quercetin and its derivatives for wound healing in rats/mice: Evidence from animal studies and insight into molecular mechanisms

Aimed to clarify the effect of quercetin and its derivatives on wound healing in animal experiments. PubMed, Embase, Science Direct, Web of Science, SinoMed, Vip Journal Integration Platform, China National Knowledge Infrastructure and WanFang databases were searched for animal experiments investigating the effect of quercetin and its derivatives on wound healing to April 2023. The Review Manager 5.4 software was used to conduct meta-analysis. Eighteen studies were enrolled in this article. According to the SYRCLE's RoB tool assessment, these studies exposed relatively low methodological quality. It was shown that animals with cutaneous wound receiving quercetin had faster wound healing in wound closure (%) than the control group. Moreover, the difference in efficacy gradually emerged after third day (WMD = 7.13 [5.52, 8.74]), with a peak reached on the tenth day after wounding (WMD = 19.78 [17.82, 21.74]). Subgroup analysis revealed that quercetin for wound closure (%) was independent of the types of rats and mice, wound area and with or without diabetes. Clear conclusion was also shown regarding the external application of quercetin for wound healing (WMD = 17.77 [11.11, 24.43]). A significant reduction in the distribution of inflammatory cells occurred in the quercetin group. Quercetin could increase blood vessel density (WMD = 1.85 [0.68, -3.02]), fibroblast distribution and collagen fraction. Biochemical indicators, including IL-1β, IL-10, TNF-α, TGF-β, vascular endothelial growth factor (VEGF), hydroxyproline and alpha-smooth muscle actin (α-SMA), had the consistent results. Quercetin and its derivatives could promote the recovery of cutaneous wound in animals, through inhibiting inflammatory response and accelerating angiogenesis, proliferation of fibroblast and collagen deposition.

Radix Salvia miltiorrhiza Ameliorates Burn Injuries by Reducing Inflammation and Promoting Wound Healing

Purpose

Radix Salvia miltiorrhiza (RSM), a commonly used medicinal plant, has been reported to have anti-inflammatory effects, but relevant studies on burn injuries are lacking. We investigated the anti-inflammation and wound healing (WH) effects of an aqueous extract of RSM on a burn model in rats.

Methods

The effects of RSM were studied by heat-induced burns in rats, treatment with vehicle, Jinwanhong ointment, and RSM (1.5 or 0.75 g/mL). Indicators of burn tissue (BT) were photographed by digital machines and analyzed. The microcirculation in BT was detected by scattered full-frame real-time imaging. Levels of inflammatory mediators and growth factors were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. Local pathologic changes in BT were observed by hematoxylin-and-eosin (HE) staining. Ultrahigh pressure liquid chromatography-linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap-MS) was used to explore the absorption of RSM in local skin, subcutaneous tissue, muscle tissue, serum, liver tissue, and kidney tissue.

Results

RSM treatment could reduce the wound area, increase percent WH, increase blood perfusion in BT, reduce serum levels of interleukin (IL)-6, IL-1, tumor necrosis factor-α (TNF-α), increase levels of epidermal growth factor (EGF), transforming growth factor (TGF)-β, and hydroxyproline (Hyp) in serum, and increase protein expression of basic fibroblast growth factor (bFGF), TGF-β1, EGF, and insulin-like growth factor-1 (IGF)-1 in skin tissues. RSM treatment led to micro-absorption in the skin, subcutaneous tissues, and muscle, but not in the blood, liver, or kidney.

Conclusion

RSM may promote WH by exerting anti-inflammatory effects, improving local-wound microcirculation, and accelerating the metabolism at the wound surface.

Bioactive Compounds from Kalanchoe Genus Potentially Useful for the Development of New Drugs

The genus Kalanchoe Adans. (Crassulaceae) is native to Madagascar and comprises 145 species, being naturalized in the tropics and cultivated worldwide. In addition to having ornamental value, several Kalanchoe species are commonly used in popular medicine for the treatment of inflammatory conditions, wounds, gastric ulcers, and other diseases. The great importance of the genus is reflected on its acknowledgment by traditional and alternative health systems and organizations, as well as on the growing number of papers reporting pharmacological properties of extracts and isolated compounds from Kalanchoe. Among these properties, we highlight anti-inflammatory, antitumor, wound healing, antiulcer, and muscle relaxing properties. These activities are attributed mostly to flavonoids and bufadienolides, the main secondary metabolites reported in Kalanchoe extracts. While bufadienolides are generally related to cytotoxic and muscle relaxing activities, flavonoids are commonly reported as anti-inflammatory and wound healing agents. This review provides up to date information and perspectives on bioactive compounds from the Kalanchoe genus that are potentially useful for the development of new drugs. It includes not only a discussion on the advantages of the Kalanchoe species as source of bioactive compounds, but also the gaps, opportunities, and challenges to translate the acquired knowledge into innovation for drug development.

Progress of EGFL6 in angiogenesis and tumor development

The epidermal growth factor (EGF) superfamily includes the protein 6 with an epidermal growth factor-like protein (EGFL6). EGFL6 has a signal peptide domain with an amino terminus and a MAM domain with a carboxy terminus. There are four whole EGF-like repeat regions and one partial EGF-like repeat region. Three of these regions include calcium-binding structures and an arg-gly-asp (RGD) integrin interaction motif. The epidermal growth factor-like (EGFL) and EGF domains have identical amino acid residues. Cell division, differentiation, mortality, cell adhesion, and migration are all affected by EGFL6. EGFL proteins are involved in a broad range of biological activities, making it important in tumor development and angiogenesis. We highlighted the latest development of EGFL6 research on tumor proliferation, invasion, and migration in this review.

Evaluation of in vivo wound healing activity of Moroccan Citrus reticulata peel extract

Background

Citrus reticulata is one of the most cultivated fruit with great benefits for humans in the world. Citrus reticulata peel has several biological activities within them hypoglycemic, hepatoprotective, antimicrobial and antioxidant. The present study emphasizes on the in vivo wound healing and in vitro antimicrobial and antioxidant activities of Citrus reticulata peel extract.

Methods

Forty albino mice (23–29 g) of either sex were divided into four groups. The test groups were treated with experimental ointment (0.5% and 10% of methanolic extract), negative control were treated with Vaseline and the positive control were treated with silver sulfadiazine. Burn wounds were induced on dorsal area of mice bodies. Wound area measurement was carried out every day during 22 days. Biochemical screening was performed to identify possible compounds. Antioxidant and antimicrobial activities were also determined.

Results

Significant wound healing activity was observed with topical application of Citrus reticulata peel extract. Wound area reduction at day 16 of treatment was 100% for both treated groups (0.5% and 10%) when compared to positive and negative control it was 100% and 98.32% respectively at day 22. Furthermore higher rate of wound contraction (100% on 16th day) was observed for both treated groups.

The result of biochemical screening showed that C. reticulata peel is characterized by highest amount of total polyphenols (13.19 mg/g), flavonoids (4.07 mg/g), vitamin C (13.20 mg/g), carotenoids (0.032 mg/g) and lowest content of macronutrients (Proteins: 0.40%, reducing sugars: 7.21%; lipids: 1.5%). Additionally C. reticulata peel exhibited remarkable antioxidant activity using DPPH and phosphomolybdate methods as well as the extract possess antimicrobial effect against pathogen bactria.

Conclusion

The findings from this research indicated that Citrus reticulata peel extract is effective in inhibiting the growth of pathogen bacteria and could be of therapeutic potentials for wound healing.

Wound healing cream formulated with Kalanchoe pinnata major flavonoid is as effective as the aqueous leaf extract cream in a rat model of excisional wound

Leaves of Kalanchoe pinnata are used worldwide for healing skin wounds. This study aimed to develop and compare two creams containing a leaf aqueous extract of K. pinnata (KP; 6%) and its major flavonoid [quercetin 3-O-α-L-arabinopyranosyl-(1→2)-α-L-rhamnopyranoside] (0.15%). Both creams were topically evaluated in a rat excision model for 15 days. On the 12^th day, groups treated with KP leaf-extract and KP major flavonoid creams exhibited 95.3 ± 1.2% and 97.5 ± 0.8% of healing, respectively (positive control = 96.7 ± 0.8%; negative control = 76.1 ± 3.8%). Both resulted in better re-epithelialization and denser collagen fibres. Flavonol glycosides are the main phenolics in KP leaf-extract according to HPLC-ESI-MS/MS analysis. KP major flavonoid plays a fundamental role in the wound healing. The similar results found for both creams indicate that the use of KP crude extract should be more profitable than the isolated compound.

The emerging role of EGFL6 in angiogenesis and tumor progression

Epidermal growth factor-like domain-containing protein 6 (EGFL6) belongs to the epidermal growth factor (EGF) superfamily. EGFL6 is expressed at higher levels in embryos and various malignant tumors than in normal tissues. Recent studies suggest that EGFL6 participates in the development of a variety of tumors. In this review, we summarize findings that support the role for EGFL6 in tumor proliferation, invasion and migration. Furthermore, our review results indicate the mechanism of EGFL6 activity angiogenesis. We also describe work toward the preparation of monoclonal antibodies against EGFL6. Altogether, the work of this review promotes understanding of the role of EGFL6 in tumor development, the mechanism of that action, and the potential of EGFL6 as a therapeutic target for tumor prevention and treatment.