Hnin Ei Thu

Alginate based bilayer hydrocolloid films as potential slow-release modern wound dressing

The aims of this research were to develop a novel bilayer hydrocolloid film based on alginate and to investigate its potential as slow-release wound healing vehicle. The bilayer is composed of an upper layer impregnated with model drug (ibuprofen) and a drug-free lower layer, which acted as a rate-controlling membrane. The thickness uniformity, solvent loss, moisture vapour transmission rate (MVTR), hydration rate, morphology, rheology, mechanical properties, in vitro drug release and in vivo wound healing profiles were investigated. A smooth bilayer film with two homogenous distinct layers was produced. The characterisation results showed that bilayer has superior mechanical and rheological properties than the single layer films. The bilayers also showed low MVTR, slower hydration rate and lower drug flux in vitro compared to single layer inferring that bilayer may be useful for treating low suppurating wounds and suitable for slow release application on wound surfaces. The bilayers also provided a significant higher healing rate in vivo, with well-formed epidermis with faster granulation tissue formation when compared to the controls. In conclusions, a novel alginate-based bilayer hydrocolloid film was developed and results suggested that they can be exploited as slow-release wound dressings.

Gelatine enhances drug dispersion in alginate bilayer film via the formation of crystalline microaggregates

In our previous study, a novel alginate-based bilayer film for slow-release wound dressings was successfully developed. We found that alginate alone yielded poor films; however, the addition of gelatine had significantly enhanced the drug dispersion as well as the physical properties. Here, an investigation of the drug-polymer interactions in the bilayer films was carried out. Drug content uniformity test and microscopy observation revealed that the addition of gelatine generated bilayer films with a homogenous drug distribution within the matrix. The FTIR and XRD data showed an increase in film crystallinity which might infer the presence of drug-polymer crystalline microaggregates in the films. DSC confirmed the drug-polymer interaction and indicated that the gelatine has no effect on the thermal behaviour of the microaggregates, suggesting the compatibility of the drug and excipients in the bilayer films. In conclusion, the addition of gelatine can promote homogenous dispersion of hydrophobic drugs in alginate films possibly through the formation of crystalline microaggregates.

Exploring recent developments to improve antioxidant, anti-inflammatory and antimicrobial efficacy of curcumin: A review of new trends and future perspectives

Curcumin derivatives have been well-documented due to their natural antioxidant, antimicrobial and anti-inflammatory activities. Curcuminoids have also gained widespread recognition due to their wide range of other activities which include anti-infective, anti-mutagenic, anticancer, anti-coagulant, antiarthrititc, and wound healing potential. Despite of having a wide range of activities, the inherent physicochemical characteristics (poor water solubility, low bioavailability, chemical instability, photodegradation, rapid metabolism and short half-life) of curcumin derivatives limit their pharmaceutical significance. Aiming to overcome these pharmaceutical issues and improving therapeutic efficacy of curcuminoids, newer strategies have been attempted in recent years. These advanced techniques include polymeric nanoparticles, nanocomposite hydrogels, nanovesicles, nanofibers, nanohybrid scaffolds, nanoconjugates, nanostructured lipid carriers (NLCs), nanoemulsion, polymeric micelles and polymeric blend films. Incorporation of curcumin in these delivery systems has shown improved solubility, transmembrane permeability, long-term stability, improved bioavailability, longer plasma half-life, target-specific delivery, and upgraded therapeutic efficacy. In this review, a range of in vitro and in vivo studies have been critically discussed to explore the pharmaceutical significance and therapeutic viability of the advanced delivery systems to improve antioxidant, anti-inflammatory and antimicrobial efficacies of curcumin and its derivatives.

Nanoencapsulation, an efficient and promising approach to maximize wound healing efficacy of curcumin: A review of new trends and state-of-the-art

Wound healing is a multifarious and vibrant process of replacing devitalized and damaged cellular structures, leading to restoration of the skins barrier function, re-establishment of tissue integrity, and maintenance of the internal homeostasis. Curcumin (CUR) and its analogs have gained widespread recognition due to their remarkable anti-inflammatory, anti-infective, anticancer, immunomodulatory, antioxidant, and wound healing activities. However, their pharmaceutical significance is limited due to inherent hydrophobic nature, poor water solubility, low bioavailability, chemical instability, rapid metabolism and short half-life. Owing to their pharmaceutical limitations, newer strategies have been attempted in recent years aiming to mitigate problems related to the effective delivery of curcumanoids and to improve their wound healing potential. These advanced strategies include nanovesicles, polymeric micelles, conventional liposomes and hyalurosomes, nanocomposite hydrogels, electrospun nanofibers, nanohybrid scaffolds, nanoconjugates, nanostructured lipid carriers (NLCs), nanoemulsion, nanodispersion, and polymeric nanoparticles (NPs). The superior wound healing activities achieved after nanoencapsulation of the CUR are attributed to its target-specific delivery, longer retention at the target site, avoiding premature degradation of the encapsulated cargo and the therapeutic superiority of the advanced delivery systems over the conventional delivery. We have critically reviewed the literature and summarize the convincing evidence which explore the pharmaceutical significance and therapeutic feasibility of the advanced delivery systems in improving wound healing activities of the CUR and its analogs.

New developments and clinical transition of hyaluronic acid-based nanotherapeutics for treatment of cancer: reversing multidrug resistance, tumour-specific targetability and improved anticancer efficacy

Abstract This review aims to overview and critically analyses recent developments in achieving tumour-specific delivery of anticancer agents, maximizing anticancer efficacy, and mitigating tumour progression and off-target effects. Stemming from critical needs to develop target-specific delivery vehicles in cancer therapy, various hyaluronic acid (HA)-conjugated nanomedicines have been fabricated owing to their biocompatibility, safety, tumour-specific targetability of drugs and genes, and proficient interaction with cluster-determinant-44 (CD44) receptors over-expressed on the surface of tumour cells. HA-based conjugation or surface modulation of anticancer drugs encapsulated nanocarriers have shown promising efficacy against the various types of carcinomas of liver, breast, colorectal, pancreatic, lung, skin, ovarian, cervical, head and neck and gastric. The success of this emerging platform is assessed in achieving the rapid internalization of anticancer payloads into the tumour cells, impeding cancer cells division and proliferation, induction of cancer-specific apoptosis and prevention of metastasis (tumour progression). This review extends detailed insight into the engineering of HA-based nanomedicines, characterization, utilization for the diagnosis or treatment of CD44 over-expressing cancer subtypes and emphasizing the transition of nanomedicines to clinical cancer therapy.

Hyaluronic Acid-Based Biomaterials: A Versatile and Smart Approach to Tissue Regeneration and Treating Traumatic, Surgical, and Chronic Wounds

ABSTRACT Wound healing is a multipart and dynamic process of replacing devitalized and damaged cellular structures and tissue layers. Numerous conventional wound dressings are employed for the management of wounds but there is a lack of absolute and versatile choice. An ideal wound healing modality should provide a moist environment, offer protection from secondary infections, eliminate wound exudate, and stimulate tissue regeneration. Hyaluronic acid (HA) has been known to promote angiogenesis, granulation tissue formation, remodeling of extracellular matrix (ECM), and wound healing. Accumulation and turnover of ECM is a hallmark of tissue injury, repair, and remodeling in wound healing. HA is a major component of ECM and plays an important role in regulating tissue injury, accelerating tissue repair, and controlling disease outcomes. A wide range of in vitro, in vivo, and clinical studies have demonstrated the wound healing efficacy of HA-based biomaterials not only in the treatment of wound in the tympanic membrane, skin, and articular cartilage but also in tracheal and corneal wound healing. Recent progress and improved therapeutic efficacy achieved through partial modification and formation of HA-based biomaterials, including HA-scaffolds, sponge-like hydrogels, anti-adhesive sheets, cultured dermal substitutes, thin membranes, and dermal matrix grafts have been discussed. The current review summarizes the evidence for the therapeutic effectiveness of HA-based biomaterials in the treatment of traumatic, surgical, and chronic wounds and tissue regeneration.

Drug nanocarrier, the future of atopic diseases: Advanced drug delivery systems and smart management of disease

Atopic dermatitis (AD) is a chronically relapsing skin inflammatory disorder characterized by perivascular infiltration of immunoglobulin-E (IgE), T-lymphocytes and mast cells. The key pathophysiological factors causing this disease are immunological disorders and the compromised epidermal barrier integrity. Pruritus, intense itching, psychological stress, deprived physical and mental performance and sleep disturbance are the hallmark features of this dermatological complication. Preventive interventions which include educational programs, avoidance of allergens, exclusive care towards skin, and the rational selection of therapeutic regimen play key roles in the treatment of dermatosis. In last two decades, it is evident from a plethora of studies that scientific focus is being driven from conventional therapies to the advanced nanocarrier-based regimen for an effective management of AD. These nanocarriers which include polymeric nanoparticles (NPs), hydrogel NPs, liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanoemulsion, provide efficient roles for the target specific delivery of the therapeutic payload. The success of these targeted therapies is due to their pharmaceutical versatility, longer retention time at the target site, avoiding off-target effects and preventing premature degradation of the incorporated drugs. The present review was therefore aimed to summarise convincing evidence for the therapeutic superiority of advanced nanocarrier-mediated strategies over the conventional therapies used in the treatment of AD.

Eurycoma longifolia as a potential alternative to testosterone for the treatment of osteoporosis: Exploring time-mannered proliferative, differentiative and morphogenic modulation in osteoblasts

ETHNOPHARMACOLOGICAL RELEVANCE Eurycoma longifolia (EL) has been well-studied traditionally as a chief ingredient of many polyherbal formulations for the management of male osteoporosis. It has also been well-recognised to protect against bone calcium loss in orchidectomised rats. AIM OF THE STUDY To evaluate the effects of EL on the time-mannered sequential proliferative, differentiative, and morphogenic modulation in osteoblasts compared with testosterone. MATERIALS AND METHODS Cell proliferation was analysed using MTS assay and phase contrast microscopy. Osteogenic differentiation of MC3T3-E1 cells was assessed through a series of characteristic assays which include crystal violet staining, alkaline phosphatase (ALP) activity and Van Gieson staining. Taken together, the bone mineralization of extra cellular matrix (ECM) was estimated using alizarin red s (ARS) staining, von kossa staining, scanning electron microscopic (SEM) and energy dispersive x-ray (EDX) analysis. RESULTS The cell proliferation data clearly revealed the efficiency of EL particularly at a dose of 25µg/mL, in improving the growth of MC3T3-E1 cells compared with the untreated cells. Data also showed the prominence of EL in significantly promoting ALP activity throughout the entire duration of treatment compared with the testosterone-treated cells. The osteogenic differentiation potential of EL was further explored by analysing mineralization data which revealed that the calcified nodule formation (calcium deposition) and phosphate deposition was more pronounced in cells treated with 25µg/mL concentration of EL at various time points compared with the untreated and testosterone treated cells. The scanning electron microscopic (SEM) analysis also revealed highest globular masses of mineral deposits (identified as white colour crystals) in the ECM of cultured cells treated with 25µg/mL concentration of EL. CONCLUSION Compared to testosterone, greater potential of EL in promoting the proliferation and osteogenic differentiation of MC3T3-E1 cells provides an in vitro basis for the prevention of male osteoporosis. Thus, we anticipate that EL can be considered as an alternative approach to testosterone replacement therapy (TRT) for the treatment of male osteoporosis.

Phytotherapeutic potential of natural herbal medicines for the treatment of mild-to-severe atopic dermatitis: A review of human clinical studies

For many decades, natural herbal medicines, polyherbal formulations and/or decoctions of plant-derived materials have widely been accepted as alternative complementary therapies for the treatment, cure or prevention of a wide range of acute and chronic skin diseases including chronic herpes, prurigo, acute and chronic wounds, psoriasis and atopic dermatitis (AD). This review was aimed to summarize and critically discuss about the therapeutic viability and clinical applicability of natural herbal medicines for the treatment of AD in human. The critical analysis of the literature revealed that oral (in the form of capsules, syrup or granules) and/or topical application (alone or in conjunction with wet-wrap dressing and/or acupuncture) of natural herbal medicines exhibit remarkable potential for the treatment of mild-to-severe AD in adults, children, infants and in the pregnant women. In this review, the clinical efficacy of various herbal formulations such as Chinese herbal therapies, Korean medicines, Iranian medicines, honey, natural herbal oils (coconut oil, olive oil and mineral oil), beeswax, dodder seeds and whey for the treatment of AD has been discussed. The clinical anti-AD efficacy of these complementary therapies has been observed in terms of down-regulation in Scoring Atopic Dermatitis (SCORAD) index, erythematic intensity, Childrens Dermatology Life Quality Index (CDLQI), Dermatology Life Quality Index (DLQI), pruritus and itching frequency, transepidermal water loss (TEWL) and expression of AD-mediated chemokines. Conclusively, we recognized that natural herbal medicines demonstrate remarkable clinical efficacy when used alone or in conjunction with other complementary therapies for the treatment of AD in patients of all ages as well as pregnant women.

Recent advances in polymer-based wound dressings for the treatment of diabetic foot ulcer: an overview of state-of-the-art

BACKGROUND Diabetic foot ulcers (DFUs) are the chronic, non-healing complications of diabetic mellitus which compels a significant burden to the patients and the healthcare system. Peripheral vascular disease, diabetic neuropathy, and abnormal cellular and cytokine/chemokine activity are among the prime players which exacerbate the severity and prevent wound repair. Unlike acute wounds, DFUs impose a substantial challenge to the conventional wound dressings and demand the development of novel and advanced wound healing modalities. In general, an ideal wound dressing should provide a moist wound environment, offer protection from secondary infections, eliminate wound exudate and stimulate tissue regeneration. OBJECTIVE To date, numerous conventional wound dressings are employed for the management of DFUs but there is a lack of absolute and versatile choice. The current review was therefore aimed to summarize and critically discuss the available evidences related to pharmaceutical and therapeutic viability of polymer-based dressings for the treatment of DFUs. RESULTS A versatile range of naturally-originated polymers including chitosan (CS), hyaluronic acid (HA), cellulose, alginate, dextran, collagen, gelatin, elastin, fibrin and silk fibroin have been utilized for the treatment of DFUs. These polymers have been used in the form of hydrogels, films, hydrocolloids, foams, membranes, scaffolds, microparticles, and nanoparticles. Moreover, the wound healing viability and clinical applicability of various mutually modified, semi-synthetic or synthetic polymers have also been critically discussed. CONCLUSION In summary, this review enlightens the most recent developments in polymer-based wound dressings with special emphasis on advanced polymeric biomaterials, innovative therapeutic strategies and delivery approaches for the treatment of DFUs.