The N-butyl alcohol extract from Hibiscus rosa-sinensis L. flowers enhances healing potential on rat excisional wounds

Review of Malaysian medicinal plants with potential wound healing activity

Wound is defined as the damage to biological tissues including skin, mucous membranes and organ tissues. The acute wound heals in less than 4 weeks without complications, while a chronic wound takes longer than 6 weeks to heal. Wound healing occurs in 4 phases, namely, coagulation, inflammatory, proliferative and remodeling phases. Triclosan and benzalkonium chloride are commonly used as skin disinfectants in wound healing. However, they cause allergic contact dermatitis and antibiotic resistance. Medicinal plants are widely studied due to the limited availability of wound healing agents. The present review included six commonly available medicinal plants in Malaysia such as Aloe barbadensis Miller, Carica papaya Linn., Centella asiatica Linn., Cymbopogon nardus Linn., Ficus benghalensis Linn. and Hibiscus rosa sinensis Linn. Various search engines and databases were used to obtain the scientific findings, including Google Scholar, ScienceDirect, PubMed Central and Research Gate. The review discussed the possible mechanism of action of medicinal plants and their active constituents in the wound healing process. In addition, their application in nanotechnology and wound dressings was also discussed in detail.

Lychnophora ericoides Mart. (Brazilian arnica) ethanol extract accelerates the skin wound healing process: Evidence for its mechanism of action

BACKGROUND

Lychnophora ericoides Mart, also known as the Brazilian arnica or fake arnica, belongs to the Asteraceae family. Leaves and roots are used in alcoholic and hydroalcoholic preparations for the treatment of wounds, inflammation, and pain.

PURPOSE

The present study aimed to investigate the effects of L. ericoides ethanolic extract (EELE) on cutaneous wound healing and the mechanisms of action involved.

METHODS

A total of 72 C57BL/6 mice were randomly divided into four groups of six animals each. An excisional wound was made in the dorsal region of each mouse. The test groups were topically treated with the vehicle, a positive control commercial reference drug, EELE ointment (5%), and EELE ointment (10%). The treatments were applied over 14 days. The wound area was measured every two days to verify the wound closure kinetics. On days 3, 7, and 14 the wound tissue samples were processed for Hematoxylin and Eosin, Masson-Trichrome, and Toluidine blue staining. The expression of renin-angiotensin system (RAS) components, the vascular growth factor-A (VEGF-A), the basic fibroblast growth factor (FGF-2), and type I collagen genes were evaluated. Phytochemical analyses were performed using HPLC-DAD and HPLC-MS/MS.

RESULTS

The EELE (10%) significantly reduced the wound area compared to the treatments used for the other groups. Histological analysis demonstrated that wounds treated with L. ericoides for 14 days developed improved anatomical skin features, healed with hair follicles and sebaceous glands, increased collagen production and angiogenesis, and decreased the number of mast cells at the injury site. Real-time PCR data demonstrated that groups treated with EELE (10%) showed increased Type I collagen, VEGF-A, FGF-2, and AT1R and decreased ACE II and receptor MAS. The healing action of L. ericoides may be related to the presence of phenolic compounds, such as phenolic acids, chlorogenic acid derivatives, and C-glycoside flavonoids.

CONCLUSION

Topical treatment with EELE increases important factors for wound healing: FGF, VEGF, collagen formation, and the expression of the proliferative axis of the renin-angiotensin system. For the first time, the present study shows the healing action of L. ericoides at the molecular level in an animal model. This process can be used as an alternative therapy for wound healing and the development of herbal therapy.

Topical effect of polyherbal flowers extract on xanthan gum hydrogel patch-induced wound healing activity in human cell lines and male BALB/c mice

Wound or injury is a breakdown in the skin's protective function as well as damage to the normal tissues. Wound healing is a dynamic and complex phenomenon of replacing injured skin or body tissues. In ancient times theCalendula officinalisandHibiscus rosa-sinensisflowers were extensively used by the tribal communities as herbal medicine for various complications including wound healing. But loading and delivery of such herbal medicines are challenging because it maintains their molecular structure against temperature, moisture, and other ambient factors. This study has fabricated xanthan gum (XG) hydrogel through a facile process and encapsulatedC. officinalisandH. rosa-sinensisflower extract. The resulting hydrogel was characterized by different physical methods like x-ray diffractometer, UV-vis spectroscopy, Fourier transform infrared spectroscopy, SEM, dynamic light scattering, electronkinetic potential in colloidal systems (ZETA) potential, thermogravimetric differential thermal analysis (TGA-DTA), etc. The polyherbal extract was phytochemically screened and observed that flavonoids, alkaloids, terpenoids, tannins, saponins, anthraquinones, glycosides, amino acids, and a few percentages of reducing sugar were present in the polyherbal extract. Polyherbal extract encapsulated XG hydrogel (X@C-H) significantly enhanced the proliferation of fibroblast and keratinocyte cell lines in comparison to the bare excipient treated cells as determined by 3-(4, 5-dimethylthiazol-2-Yl)-2, 5-diphenyltetrazolium bromide assay. Also, the proliferation of these cells was confirmed by BrdU assay and enhanced expression of pAkt. In anin-vivostudy, wound healing activity of BALB/c mice was carried out and we observed that X@C-H hydrogel showed significant result compared to the other groups (untreated, X, X@C, X@H). Henceforth, we conclude that this synthesized biocompatible hydrogel could emerge as a promising carrier of more than one herbal excipients.

Advanced drug delivery systems containing herbal components for wound healing

Management of chronic wound has an immense impact on social and economic conditions in the world. Healthcare costs, aging population, physical trauma, and comorbidities of diabetes and obesity seem to be the major factors of this increasing incidence of chronic wounds. Conditions of chronic wound could not restore functional epidermis; thus, delaying the closure of the wound opening in an expected manner. Failures in restoration of skin integrity delay healing due to changes in skin pathology, such as chronic ulceration or nonhealing. The role of different traditional medicines has been explored for use in the healing of cutaneous wounds, where several phytochemicals, such as flavonoids, alkaloids, phenolic acids, tannins are known to provide potential wound healing properties. However, the delivery of plant-based therapeutics could be improved by the novel platform of nanotechnology. Thus, the objectives of novel delivery strategies of principal bioactive from plant sources are to accelerate the wound healing process, avoid wound complications and enhance patient compliance. Therefore, the opportunities of nanotechnology-based drug delivery of natural wound healing therapeutics have been included in the present discussion with special emphasis on nanofibers, vesicular structures, nanoparticles, nanoemulsion, and nanogels.

Green and Chemical Silver Nanoparticles and Pomegranate Formulations to Heal Infected Wounds in Diabetic Rats

Infected cutaneous ulcers from diabetic rats with Candida albicans and Streptococcus aureus were treated with spray formulations containing green silver nanoparticles (GS), chemical silver nanoparticles (CS), or pomegranate peel extract (PS). After wound development and infection, the treatments were performed twice per day for 14 days. The wound healing was analyzed on days 2, 7, and 14 through the determination of CFUs, inflammatory infiltrate, angiogenesis, fibroplasia, myeloperoxidase, and collagen determination. Expressive improvement in wound healing was noted using both silver nanoparticles for 7 days. All the treatments were superior to controls and promoted significant S. aureus reduction after 14 days. CS presented better anti-inflammatory results, and GS and CS the highest number of fibroblasts. Despite the techniques' limitations, GS and CS demonstrated considerable potential for managing infected wounds, especially considering no early strategies prior to the drugs, such as the debridement of these wounds, were included.

Compendium of Conventional and Targeted Drug Delivery Formulation Used for the Treatment and Management of the Wound Healing

Wound healing is a complex and dynamic phenomenon that involves the restoration of normal physiology and functioning of injured tissue. The process of wound healing is primarily regulated by various cytokines, inflammatory mediators, and growth factors at the molecular level. Any intervention in the normal wound healing process leads to further tissue damage, which in turn leads to delayed wound healing. Several natural, synthetic drugs and their combinations were used to restored and accelerate the wound healing process. However, the conventional delivery carriers were not much effective, and thus, nowadays, nanocarriers are gaining much popularity since they are playing a pivotal role in drug delivery. Since nanocarriers have their own applicability and benefits (enhance the bioavailability, site-specific targeting) so, they can accelerate wound healing more efficiently. This review briefly discussed about the various events that take place during the wound healing process with emphasis on various natural, synthetic, and combination drug therapy used for accelerating wound healing and the role of nanotechnology-based approaches in chronic wound healing.

In-vivo wound healing activity of a novel composite sponge loaded with mucilage and lipoidal matter of Hibiscus species

Many researches have been undergone to hasten the natural wound healing process. In this study, several Hibiscus species (leaves) were extracted with petroleum ether, methanol, and their mucilage was separated. All the tested species extracts were assessed for their viability percentage using the water-soluble tetrazolium. H.syriacus was the plant of choice to be incorporated in a new drug delivery system and evaluated for its wound healing activity. H.syriacus petroleum ether extract (PEE) showed a high percentage of palmitic and oleic acids while its mucilage demonstrated high glucosamine and galacturonic acid. It was selected to be formulated and pharmaceutically evaluated into three different composite sponges using chitosan in various ratios. Fourier-transformed infrared spectroscopy investigated the chemical interaction between the utilized sponges' ingredients. Morphological characteristics were evaluated using scanning electron microscopy. H.syriacus composite sponge of mucilage: chitosan (1:5) was loaded with three different concentrations of PEE. Medicated formulations were assessed in rat model of excision wound model. The wound healing ability was clearly proved by the clinical acceleration, histopathological examination, and modulation of correlated inflammatory parameters as tumor necrosis factor in addition to vascular endothelial growth factor suggesting a promising valuable candidate that supports the management of excision wounds using single-dose preparation.

Anti-inflammatory, analgesic and in vivo-in vitro wound healing potential of the Phlomis rigida Labill. extract

ETHNOPHARMACOLOGICAL RELEVANCE

The preparations of Phlomis aerial parts are used traditionally in Anatolia for wound healing and in inflammatory disorders.

METHODS

For the identification of the active fraction, the air dried aerial parts of Phlomis rigida Labill. were extracted by methanol and fractionated successively by n-hexane, dichloromethane and ethyl acetate, respectively. The phenolic constituents were characterized by the Folin-Ciocaltheu method; the antioxidant activity was performed by ABTS and DPPH radical scavenging assays. In vitro anti-inflammatory activity was evaluated by LOX enzyme inhibition, spectrophotometrically as well as cell cultures. The wound healing properties of P. rigida extract gels were studied via in vitro cell culture methods and in vivo by excisional wound model using Balb-c mice. The P. rigida extract was analyzed and characterized by GC-FID, GC-MS, and LC-MS.

RESULTS

The P. rigida methanol extract showed moderate LOX inhibitory at IC₅₀ = 19.5 ± 2.8 μg/mL whereas the antioxidant activity was by DPPH^• IC₅₀ = 0.89 mg/mL, and by ABTS^• IC₅₀ = 0.99 mg/mL, respectively. In addition, a remarkable P. rigida extracts anti-inflammatory activity was observed in the cell culture assay, which was then confirmed by the in vitro wound healing activity applied at 0.125-0.5 mg/mL concentrations, resulting in a dose-dependent increase in wound closure at the final stage. The P. rigida gel formulation was prepared to evaluate the extract in vivo, whereas the experimental results of the new gel formulation supported the findings of the in vitro wound healing activity.

CONCLUSION

The findings of this in vitro and in vivo study suggest that the wound healing and anti-inflammatory properties provide a scientific evidence of the ethnopharmacological application of Phlomis species.

Preparative HPLC fraction of Hibiscus rosa-sinensis essential oil against biofilm forming Klebsiella pneumoniae

Recent years Klebsiella pneumoniae (K. pneumoniae) biofilm formation (BF) is emerging thread worldwide. For tackling this problem, we have chosen Hibiscus rosa-. pneumoniae. The HPLC purified essential oils (EOs sinensis (H. rosa-sinensis) (HRS) to inhibit the BF K) of H. rosa-sinensis was performed against BF K. pneumoniae and showed concentration dependent biofilm inhibition. At the MBIC of EOs (90 µg/ml), the biofilm inhibition was showed at 92% against selected BF K. Pneumoniae. The biofilm metabolic assay, exopolysaccharide quantification and hydrophobicity index variation results exhibited with 88%, 92% and 89% reduction at 90 μg/mL was observed respectively. In addition, the morphological modification of MBIC treated K. pneumoniae was clearly viewed by scanning electron microscope (SEM). Overall, all the invitro experiments result were confirmed that the MBIC of H. rosa-sinensis EOs was very effective against BF K. pneumonia.

Development and Characterization of Squalene-Loaded Topical Agar-Based Emulgel Scaffold: Wound Healing Potential in Full-Thickness Burn Model

Full-thickness burns pose a major challenge for clinicians to handle because of their restricted self-healing ability. Even though several approaches have been implemented for repairing these burnt skin tissue defects, all of them had unsatisfactory outcomes. Moreover, during recent years, skin tissue engineering techniques have emerged as a promising approach to improve skin tissue regeneration and overcome the shortcomings of the traditional approaches. Although previous literatures report the wound healing effects of the squalene oil, in the current study, for the first time, we developed a squalene-loaded emulgel-based scaffold as a novel approach for potential skin regeneration. This squalene-loaded agar-based emulgel scaffold was fabricated by using physical cross-linking technique using lecithin as an emulsifier. Characterization studies such as X-ray diffraction, Fourier-transform infrared spectroscopy, and field emission scanning electron microscopy revealed the amorphous nature, chemical interactions, and cross-linked capabilities of the developed emulgel scaffold. The squalene-loaded emulgel scaffold showed excellent wound contraction when compared with the agar gel and negative control. In case of the histopathology and recent immunohistochemistry findings, it was clearly evidenced that squalene-loaded emulgel promoted faster rate of the revascularization and macrophage polarization in order to enhance the burn wound healing. Moreover, the findings also revealed that the incorporation of squalene oil into the formulation enhances collagen deposition and accelerates the burnt skin tissue regeneration process. Finally, we conclude that the squalene-loaded emulgel scaffold could be an effective formulation used in the treatment of the burnt skin tissue defects.

Effects of 4-CPPU on in vitro multiplication and sustainable generation of Hibiscus rosa-sinensis L. 'White Butterfly'

There are more than nine thousand cultivars of Hibiscus rosa-sinensis L., with a series of flowers with shapes, colors and new cultivars continues as generated through both traditional and modern breeding techniques. In this study, advanced biotech methods of in vitro culture have been used to identify a technique for the efficient mass multiplication of H. rosa-sinensis ‘White Butterfly’, using phenyl urea, N-(2-Chloro-4-pyridyl)-N′-phenylurea (4-CPPU). For the first time, the effects of 4-CPPU for stimulating axillary shoot proliferation and multiple shoot regenerations from nodal explants were evaluated, and the optimal nutrient media deduced. From the diverse concentrations as 0.1, 0.5, 2.5, 5.0 & 10.0 µM of 4-CPPU, the highest frequency of shoots was recorded at 2.5 µM supplied in Murashige and Skoog (MS, pH-5.8) medium. After eight-weeks of culture, on an average of 6.7 shoot were obtained on this media with shoot heights of 4.2 cm from each explant. With the involvement of 0.5 µM-IBA (indole-3-butyric acid) in MS medium the regenerated shoots were rooted and followed by successful acclimation to ex vitro conditions. The ploidy consistency among the micro-plants was analyzed using flow cytometry and compared with ex vitro grown plants. No differences in the ploidy levels were observed among the 4-CPPU induced plants, when compared with the donor plants.

Wound Healing and the Use of Medicinal Plants

Cutaneous wound healing is the process by which skin repairs itself. It is generally accepted that cutaneous wound healing can be divided into 4 phases: haemostasis, inflammation, proliferation, and remodelling. In humans, keratinocytes re-form a functional epidermis (reepithelialization) as rapidly as possible, closing the wound and reestablishing tissue homeostasis. Dermal fibroblasts migrate into the wound bed and proliferate, creating “granulation tissue” rich in extracellular matrix proteins and supporting the growth of new blood vessels. Ultimately, this is remodelled over an extended period, returning the injured tissue to a state similar to that before injury. Dysregulation in any phase of the wound healing cascade delays healing and may result in various skin pathologies, including nonhealing, or chronic ulceration. Indigenous and traditional medicines make extensive use of natural products and derivatives of natural products and provide more than half of all medicines consumed today throughout the world. Recognising the important role traditional medicine continues to play, we have undertaken an extensive survey of literature reporting the use of medical plants and plant-based products for cutaneous wounds. We describe the active ingredients, bioactivities, clinical uses, formulations, methods of preparation, and clinical value of 36 medical plant species. Several species stand out, including Centella asiatica, Curcuma longa, and Paeonia suffruticosa, which are popular wound healing products used by several cultures and ethnic groups. The popularity and evidence of continued use clearly indicates that there are still lessons to be learned from traditional practices. Hidden in the myriad of natural products and derivatives from natural products are undescribed reagents, unexplored combinations, and adjunct compounds that could have a place in the contemporary therapeutic inventory.

In situ gelation of rhEGF-containing liquid crystalline precursor with good cargo stability and system mechanical properties: a novel delivery system for chronic wounds treatment

The objective of this study was to develop a novel delivery system for recombinant human epidermal growth factor (rhEGF) for chronic wound treatment. Such a delivery system should be of good cargo stability and system mechanical properties in order to guarantee a satisfactory wound-healing effect. rhEGF-containing lyotropic liquid crystalline precursors (rhEGF-LLCPs) with in situ gelation capability were considered as a promising candidate to achieve this aim. Various properties of the optimal formulations (rhEGF-LLCP1 and rhEGF-LLCP2) were characterized, including apparent viscosity, gelation time, in vitro release and phase behavior. The stability of rhEGF and system mechanical properties (i.e. mechanical rigidity and bioadhesive force) were verified. Interestingly, rhEGF-LLCP2 with a larger internal water channel diameter exhibited faster release rate in vitro and then better bioactivity in Balb/c 3T3 and HaCaT cell models. Moreover, rhEGF-LLCP2 showed distinct promotion effects on wound closure, inflammatory recovery and re-epithelization process in Sprague-Dawley rat models. In conclusion, rhEGF-LLCP emerged as a prospective candidate to preserve the stability and enhance the wound-healing effect of rhEGF, which might serve as a new delivery system for chronic wound therapies.

Novel insight into wound healing properties of methanol extract of Capparis ovata Desf. var. palaestina Zohary fruits

Objectives

The objective of this study was to investigate the wound healing activity of Capparis ovata var. palaestina fruit extract in mice. For this aim, wound healing, in vitro antimicrobial and antioxidant activities, HPLC, phenolic and flavonoid compounds analyses were performed.

Methods

The wound healing effect was tested by excisional wound model. Wound closure was measured for 14 days and at 14th day wound healing was assessed by levels of TGF-β, VEGF, COL1A1 and angiogenesis, granulation tissue thickness, epidermal and dermal regeneration. The antioxidant activity was calculated by DPPH and ABTS free radical scavenging assays. Antimicrobial ability was evaluated by minimum inhibitory concentration and agar well diffusion tests.

Key findings

The extract indicated significant antioxidant activity while it also exhibited antimicrobial activity. Rutin was found in the extract according to HPLC study. Moreover, the extract was found to have rich phenolic and flavonoid contents. Histological evaluation showed that extract group induced significant (P < 0.001) wound healing activity compared to control group. Furthermore, extract group increased wound healing rates by promoting granulation tissue, epidermal regeneration, angiogenesis, collagen, TGF-β and VEGF.

Conclusions

The results clarified that the extract possesses antioxidant, antimicrobial activity and thus could provide a valuable contribution to the wound healing.

Electrospun Heparin-Loaded Core-Shell Nanofiber Sutures for Achilles Tendon Regeneration In Vivo

Achilles tendon reconstruction surgery is the primary clinical method for repairing acute Achilles tendon ruptures. However, the efficacy of the postoperative healing process and the recovery of physiological function are inadequate. This study examines the healing mechanism of ruptured rat Achilles tendons seamed with heparin-loaded core-shell fiber sutures fabricated via near-field electrospinning. High-heparin-concentration sutures (PPH3.0) perform better than the low-heparin-concentration sutures and commercial sutures (CSs). The PPH3.0 suture recruits fewer inflammatory cells and shows good histocompatibility in peritoneal implantation experiments. Staining of the Achilles tendon rupture repair zone demonstrates that a high heparin concentration in sutures reduces immune-inflammatory responses. Immunohistochemical analysis reveals that the transforming growth factor-β staining scores of the PPH3.0 sutures are not significantly different from those of the corresponding control group but are significantly different from those of the CSs and non-heparin-loaded-suture groups. According to vascular endothelial growth factor (VEGF) analysis, the concentration of VEGF in the group treated with the PPH3.0 suture increases by 37.5% compared with that in its control group. No significant difference in tension strength is observed between the PPH3.0 group and healthy Achilles tendons. These findings illustrate that this novel method effectively treats Achilles tendon rupture and promotes healing and regeneration.

Danggui Buxue Extract-Loaded Liposomes in Thermosensitive Gel Enhance In Vivo Dermal Wound Healing via Activation of the VEGF/PI3K/Akt and TGF-β/Smads Signaling Pathway

Danggui Buxue extract-loaded liposomes in thermosensitive gel (DBLTG) are a sustained-release local drug delivery system derived from Danggui Buxue decoction, a well-known Chinese herb formula with wound healing potential. In the present study, we investigated the therapeutic effects of DBLTG on dorsal full-thickness excisional wounds in rats by measuring the percentage of wound contraction and hydroxyproline content, as well as conducting histological observations and immunohistochemical analysis. We also assessed involvement of the vascular endothelial growth factor (VEGF)/phosphatidylinositol 3-kinase (PI3K)/Akt and transforming growth factor beta (TGF-β)/Smads signaling pathways in the wound healing process upon DBLTG treatment via western blot. The results show that DBLTG treatment remarkably accelerates wound closure, enhances hydroxyproline content in wound granulation tissue, promotes cutaneous wound healing by reducing the inflammatory response and improving fresh granulation tissue formation, and significantly increases the density of blood vessels, cells proliferation, and expression of type I and type III collagen. Moreover, DBLTG markedly upregulates the relative protein expression of VEGFA and TGF-β1 and notably stimulates the phosphorylation of Akt and Smad2/3. In conclusion, DBLTG significantly improved dermal wound healing in rats by stimulating angiogenesis and collagen synthesis; these effects are likely mediated via the VEGF/PI3K/Akt and TGF-β/Smads signaling pathways, respectively.