Development of a self-microemulsifying drug delivery system to deliver delamanid via a pressurized metered dose inhaler for treatment of multi-drug resistant pulmonary tuberculosis.

Tuberculosis (TB) is a serious health issue that contributes to millions of deaths throughout the world and increases the threat of serious pulmonary infections in patients with respiratory illness. Delamanid is a novel drug approved in 2014 to deal with multi-drug resistant TB (MDR-TB). Despite its high efficiency in TB treatment, delamanid poses delivery challenges due to poor water solubility leading to inadequate absorption upon oral administration. This study involves the development of novel formulation-based pressurized metered dose inhalers (pMDIs) containing self-microemulsifying mixtures of delamanid for efficient delivery to the lungs. To identify the appropriate self-microemulsifying formulations, ternary diagrams were plotted using different combinations of surfactant to co-surfactant ratios (1:1, 2:1, and 3:1). The combinations used Cremophor RH40, Poly Ethylene Glycol 400 (PEG 400), and peppermint oil, and those that showed the maximum microemulsion region and rapid and stable emulsification were selected for further characterization. The diluted self-microemulsifying mixtures underwent evaluation of dose uniformity, droplet size, zeta potential, and transmission electron microscopy. The selected formulations exhibited uniform delivery of the dose throughout the canister life, along with droplet sizes and zeta potentials that ranged from 24.74 to 88.99 nm and - 19.27 to - 10.00 mV, respectively. The aerosol performance of each self-microemulsifying drug delivery system (SMEDDS)-pMDI was assessed using the Next Generation Impactor, which indicated their capability to deliver the drug to the deeper areas of the lungs. In vitro cytotoxicity testing on A549 and NCI-H358 cells revealed no significant signs of toxicity up to a concentration of 1.56 µg/mL. The antimycobacterial activity of the formulations was evaluated against Mycobacterium bovis using flow cytometry analysis, which showed complete inhibition by day 5 with a minimum bactericidal concentration of 0.313 µg/mL. Moreover, the cellular uptake studies showed efficient delivery of the formulations inside macrophage cells, which indicated the potential for intracellular antimycobacterial activity. These findings demonstrated the potential of the Delamanid-SMEDDS-pMDI for efficient pulmonary delivery of delamanid to improve its effectiveness in the treatment of multi-drug resistant pulmonary TB.

Assessing the Anti-Aging and Wound Healing Capabilities of Etlingera elatior Inflorescence Extract: A Comparison of Three Inflorescence Color Varieties.

Torch ginger, Etlingera elatior, is a Zingiberaceae plant with various red, pink, and white inflorescence. The wound healing potential and anti-aging effects of freeze-dried torch ginger inflorescence extracts (FTIEs) from three varieties were compared. The red FTIE had the highest content of phenolic, flavonoid, caffeoylquinic acid, and chlorogenic acid, followed by the white and pink FTIE. Consistent with the chemical constituents, the red FTIE demonstrated the greatest capacities for free radical scavenging, anti-tyrosinase, and anti-collagenase activity, followed by the white and pink FTIE. In cell-based studies, FTIEs displayed cytotoxicity to B16F10 melanoma cells, with the red FTIE showing the greatest activity (LC50 of 115.5 µg/mL). In contrast, the pink and the white FTIEs had less cytotoxicity impact. Nonetheless, at 1000 µg/mL, all three FTIE variants were safe on L929 fibroblasts or RAW 264.7 monocyte cells. White FTIE (500 µg/mL) exhibited the highest activity in stimulating collagen production and the greatest impact on cell migration, whereas the pink and red FTIE had a lesser effect. All FTIEs slightly suppressed the pro-inflammatory cytokines produced by lipopolysaccharide-stimulated monocytes, with no significant variation between FTIE variants. In conclusion, all FTIEs revealed promising potential for anti-aging cosmeceuticals and wound care products at specific concentrations.

Safety and Biocompatibility of Mupirocin Nanoparticle-Loaded Hydrogel on Burn Wound in Rat Model.

Mupirocin nanoparticle-loaded hydrogel (MLH) was successfully developed. This study focused on the safety of cell lines and the biocompatibility of MLH for wound healing in rat models. MLH was assessed by an analysis of cytotoxicity and the secretion of inflammatory cytokines in cell lines. The cytocompatibility of MLH was compared with mupirocin ointment on full-thickness burn wounds in rats. The results indicated that MLH and blank hydrogel had no toxicity to human epidermal keratinocytes and human fibroblast cells. MLH inhibited lipopolysaccharide (LPS) activity in macrophage-like cells resulting in low nitric oxide production and reduced inflammatory cytokine production (interleukin (IL)-1ß) compared with a positive control (LPS only). In burn wounds, MLH and hydrogel healed the wound better than the other groups determined by wound contraction, reduced secretion, and the generation of new blood vessels, as well as promotion of hair follicle cells. Better granulation tissue proliferation, less necrosis, and a lower degree of inflammation were found in the MLH and blank hydrogel than in the mupirocin ointment. The hydrogel group reduced the macrophages (CD68) on day 14 at the edge of the wound. On day 28, T cells (CD3), B cells (CD20), and CD68+ cells were concentrated in the deeper subcutaneous tissue. Additionally, the transforming growth factor ß1 (TGF-ß1) concentration and matrix prometalloproteinase-2/tissue inhibitor of metalloproteinases-2 ratio in the MLH and hydrogel groups were less than those in the other groups. The MLH formulation was safe and effective in burn wound healing. Therefore, MLH formulations are promising candidates for further evaluation in clinical trials.

Development of a Sildenafil Citrate Microemulsion-Loaded Hydrogel as a Potential System for Drug Delivery to the Penis and Its Cellular Metabolic Mechanism.

Sildenafil citrate is used to treat mild to moderate erectile dysfunction and premature ejaculation. However, it has low oral bioavailability, numerous adverse effects, and delayed onset of action. These problems may be resolved by transdermal delivery to the penis. Hence, sildenafil citrate was formulated as a microemulsion system using isopropyl myristate, Tween 80, PEG400, and water (30:20:40:10). The hydrogel used in the microemulsion was 2% w/w poloxamer 188. The sildenafil microemulsion-loaded hydrogels were characterised for their appearance, particle size, pH, spreadability, swelling index, viscosity, sildenafil drug content, membrane permeation, epithelial cell cytotoxicity, and in vitro drug metabolism. The optimised formulated microemulsion showed the lowest droplet size and highest solubility of sildenafil citrate. The in vitro skin permeation of the sildenafil citrate microemulsion-loaded hydrogel was significantly higher than that of the sildenafil suspension, with a 1.97-fold enhancement ratio. The formulated microemulsion exhibited a 100% cell viability, indicating its safety for skin epithelial cells. The major metabolic pathway of sildenafil citrate loaded in the microemulsion formulation was hydroxylation. Furthermore, loading sildenafil in the microemulsion reduced the drug metabolite by approximately 50% compared to the sildenafil in aqueous suspension. The sildenafil citrate-loaded isopropyl myristate-based microemulsion hydrogels were physically and chemically stable over 6 months of storage. The sildenafil citrate microemulsion-loaded hydrogel showed in vitro results suitable for used as a transdermal drug delivery system.

In Vitro Studies of Jatropha curcas L. Latex Spray Formulation for Wound Healing Applications.

OBJECTIVES: There is an increasing demand for wound healing products of natural origin. Our objective was to develop a spray formulation from Jatropha curcas (J. curcas) L. latex extracts for wound healing applications. MATERIALS AND METHODS: J. curcas L. latex was subjected to solvent extraction. The phytochemical structure was elucidated by 1H-NMR and confirmed by liquid chromatography-mass spectrometer spectrometry. A topical spray formulation prepared from J. curcas latex extracts was evaluated in terms of its antimicrobial activity and radical scavenging activity. The toxicity of the formulation on fibroblast cell lines, collagen production, and wound healing activities were tested. RESULTS: The 1H-NMR and mass spectrometric analyses revealed the pure compound as curcacycline A. The J. curcas latex extract formulation had radical scavenging and antibacterial activities. Moreover, the formulation was not toxic to the human fibroblast cells and it stimulated collagen production and healed cell injury in 24 h. CONCLUSION: The J. curcas latex extract promoted wound healing after cell injury. Our findings indicate the possibility of utilizing the J. curcas latex extract spray formulation as a potential antibacterial, antioxidant, and wound healing product from nature.

Dental floss impregnated with povidone-iodine coated with Eudragit L-100 as an antimicrobial delivery system against periodontal-associated pathogens.

Introduction. Periodontitis is among the most widespread oral bacterial diseases affecting 15-20% of the world population.Aim. This study aimed to develop dental floss impregnated with povidone-iodine (PVP-I) as an antimicrobial delivery system against periodontopathogenic bacteria in a planktonic form and within biofilms.Methods. Identical lengths of dental floss impregnated with PVP-I formulations were placed on agar along with previously grown periodontal pathogens. The bioactivity of the dental floss was investigated by response-surface methodology. In order to explore the antibacterial activity of the selected formulation and the potential application in the prevention and treatment of plaque-caused diseases such as periodontitis and caries, the antibacterial and anti-biofilm activity of the selected PVP-I formulation against pathogenic bacteria were investigated.Results. The results indicated that the coating formulation containing Eudragit L-100 2.90 %, PVP-I 24.58 % and PEG 400 3.73 % had antimicrobial activity for all pathogens. The mechanism of this formulation involved disruption of bacterial cell membranes. Moreover, this formulation inhibited the formation of oral pathogenic biofilms.Conclusion. It was concluded that Eudragit L-100 and PVP-I-coated dental floss represented a potential therapeutic agent to prevent periodontal diseases and dental caries and exhibited non-toxicity to periodontal ligament cells.

Binding interactions of bacterial lipopolysaccharides to polymyxin B in an amphiphilic carrier 'sodium deoxycholate sulfate'.

This work presents the outcomes of a comparative study of molecular interactions of polymyxin B (PMB) and F12 and F13 formulations in the mole ratios of 1:2 and 1:3 of PMB:sodium deoxycholate sulfate (SDCS), respectively, and a commercial PMB formulation (CPMB) with lipopolysaccharides (LPS). Several spectroscopic and interfacial studies were performed to obtain LPS-peptide interactions at a molecular level. The fluorescence titrimetry method revealed that the F12 formulation (325 nM) exhibited a lower number of binding sites to the LPS compared to CPMB and F13 as well as PMB alone (537 nM). Similarly, in the presence of LPS, the F12 formulation (88 nm) exhibited smaller particle sizes in the dynamic light scattering study compared to PMB (116 nm), CPMB, and the F13 formulation. An interfacial study and circular dichroism spectroscopy revealed PMB and CPMB insertion into the LPS micelles to destabilize and disrupt the LPS membrane, whereas the F12 and F13 formulations may induce pseudo-aggregation. The NMR and IR studies showed that the presence of SDCS, the hydrophobicity of PMB increased by hydrogen bonding and electrostatic interactions and formed stabilized PMB-SDCS micelles. The PMB-SDCS formulation is likely to release PMB for easy penetration into the lipid membrane and cause disruption of the complex LPS micelles. Furthermore, the PMB-SDCS formulations neutralized and detoxified the LPS micelles with minimal toxicity to normal kidney tubular cells as well as an immortalised kidney cell line. The antimicrobial properties of PMBloaded SDCS nanomicelles were effective against a resistant strain of Pseudomonas aeruginosa.

Bioactivity, Safety, and Efficacy of Amphotericin B Nanomicellar Aerosols Using Sodium Deoxycholate Sulfate as the Lipid Carrier.

We report nanomicelles of amphotericin B (AmB) using various molar ratios of AmB and sodium deoxycholate sulfate (SDCS) for inhalation with improved stability, solubility, bioactivity, and safety. The particle sizes of all aerosolized formulations are expressed as mass median aerodynamic diameter (0.9-1.6 µm), fine particle fraction (70.3-86.5%), and geometric standard deviation (1.4-2.1) which indicated their sizes are appropriate for use as an inhaler. In vitro cytotoxicity studies conducted using respiratory and kidney cell lines demonstrated that the marketed Fungizone® was toxic to macrophage and embryonic kidney cells and cell viability decreased from 96 to 48% and from 97 to 67%, respectively when the AmB equivalent concentration was increased from 1 to 16 µg/mL. However, AmB-SDCS formulations showed no evidence of toxicity even up to 8 µg/mL compared to Fungizone®. Minimum inhibitory and fungicidal concentrations were significantly reduced against Cryptococcus neoformans, and Candida albicans. Also, antileishmanial activity significantly improved for AmB-SDCS formulations. There was an evidence of phagocytosis of the AmB-SDCS formulation by alveolar macrophages NR 8383. Molecular modeling studies suggested the role of hydrogen bonding in stabilization of the AmB-SDCS complex. This study indicated that AmB-SDCS nanomicelles can be used to design a safe and cost-effective AmB for inhalation. Graphical abstract ᅟ.

Anti-biofilm properties of a mupirocin spray formulation against Escherichia coli wound infections.

Mupirocin ointment is a widely used topical drug for the treatment of bacterial skin infections. However, ointments have some limitations which motivated the development of a film forming spray of mupirocin. Mupirocin spray (2%) was formulated with Eudragit E100 as a film forming agent and tested for its antibacterial and anti-biofilm activities against Escherichia coli, a skin pathogen causing wound and surgical site infections. Treatment with mupirocin spray resulted in significant antibacterial and anti-biofilm activities (inhibition and disruption) with single spray and sub-actual dose concentrations at par with the commercial ointment concentration. The spray formulation was found to be non-toxic to fibroblast cells and greatly resisted removal from the site of application upon washing, in contrast to the ointment which was significantly removed after a single wash. This is the first study to develop and evaluate a spray formulation for mupirocin that forms a stable thin film for sustained release of the drug.

Development of a topical mupirocin spray for antibacterial and wound-healing applications.

OBJECTIVE: The aim of this study was to develop mupirocin topical spray using Eudragit E100 as a film-forming agent for the treatment of bacterial skin infections as well as to promote wound healing. MATERIALS AND METHODS: Twenty-seven of mupirocin formulations were formulated containing Eudragit E100 and other excipients. Mupirocin spray was prepared by aerosol crimping and filling machine using HFA-134a as a propellant. The formulations were evaluated for their stability and physicochemical properties. The factorial study was applied to evaluate the effects of glycerol and PEG400 on mupirocin-loaded Eudragit E100 films. The optimized formulation was assessed of drug release, antibacterial activities and in vitro cell line studies in comparison to the ointment formulation. RESULTS AND DISCUSSION: Mupirocin sprays were formulated and optimized to obtain the formulation with excellent physicochemical and mechanical properties of the dressing film. The formulation had an excellent stability up to a year with more than 80% of mupirocin content. Mupirocin was released from the film up to 90% within 2 h. The formulation had a potent antibacterial effect against S. aureus and S. epidermidis. The formulation was safe to use as a topical formulation that had no toxicity to keratinocytes, fibroblasts and monocytes. The formulation also had an antiendotoxin effect without stimulating the production of NO and inflammatory cytokines (IL-1ß and TNF-α). CONCLUSIONS: Mupirocin topical spray was successful developed as a topical formulation and can be used instead of the ointment formulation. Animal experiments are warranted to further emphasize the safe use in the human skin.

Evidences for salbutamol metabolism by respiratory and liver cell lines.

This study aimed to investigate the enantiomeric biotransformation of salbutamol in the human respiratory and liver cells. The cells from the different cell growth cycles were treated with various concentrations of salbutamol sulfate. Salbutamol and its metabolites were analyzed using chiral liquid chromatography and mass spectrometry. There were no metabolites of salbutamol found in the extracellular medium, intracellular, and cell lysate of respiratory cell lines. The S/R ratios of salbutamol were found to be 0.99-1.10 in all cell lines, cell cycles, and salbutamol concentrations in this study. Salbutamol metabolites were found only in intracellular HepG2 cells. The S/R ratios of the salbutamol inside the liver cells were 10 times greater than the S/R ratios of the salbutamol in the liver extracellular medium (0.99-1.10). It is important to note that the S/R ratios of salbutamol in liver cell lysate enzyme were 0.99-1.10 whereas the S/R salbutamol metabolites inside the liver cell were around 1.91-2.14. Both salbutamol and sulfate conjugation metabolites were detected in MS chromatograms with an m/z of 239.2 and 317.6, respectively. Hence, the delivery of salbutamol directly to the respiratory system is a right target that can avoid first-pass metabolism.

Toxicity evaluation of cordycepin and its delivery system for sustained in vitro anti-lung cancer activity.

In the previous study, we have found that the cordycepin which was extracted from Cordyceps mycelia produced by growing Cordyceps militaris on the dead larva of Bombyx mori silkworms showed the anti-proliferative effect toward lung cancer cells without toxicity to non-cancer cells. In this work, the cordycepin was tested for its in vitro mutagenicity and in vivo toxicity. From the Ames test and subacute toxicity test using oral administration in a rat model, the cordycepin was proved to be a non-mutagenic and non-toxic compound. The hematology and blood chemistry as well as the microanatomical characteristic of the tissues of rats fed with cordycepin every day for consecutive 30 days were comparable to those of the normal ones. Then, the cordycepin was incorporated in gelatin type A (GA) and gelatin type B (GB) nanoparticles aimed to sustain its release and activity. The cordycepin incorporated in both GA and GB nanoparticles showed the sustained release profiles. GA nanoparticles could encapsulate cordycepin at higher encapsulation efficiency due to the attractive electrostatic interaction between the positive-charged GA and the negative-charged cordycepin. However, GA nanoparticles released cordycepin at the higher amount possibly because of the large surface area of small size nanoparticles. Comparing to GB nanoparticles, the higher amount of cordycepin released from GA nanoparticles showed the higher anti-proliferative and anti-migratory effects on A549 lung cancer cells. In conclusion, GA nanoparticles were suggested as a suitable carrier for the sustained release of cordycepin. The GA nanoparticles releasing cordycepin could be an effective and non-invasive material for the treatment of lung cancer cells.

The safety of ethambutol dihydrochloride dry powder formulations containing chitosan for the possibility of treating lung tuberculosis.

OBJECTIVE: The aim of this study was to conduct in vitro studies of a dry powder formulation of ethambutol dihydrochloride (EDH) to determine if it was an acceptable candidate for further in vivo studies to target alveolar macrophages for the treatment of lung tuberculosis. MATERIALS AND METHODS: Nanosized drug particles were prepared by optimizing the spray drying conditions. The cell toxicities were determined by interacting the formulations with respiratory cell lines (A549, calu-3 and NR8383 cell lines), and phagocytosis of the formulations was tested on a macrophage cell line. Permeations of the EDH formulations across a lipid bilayer were studied using the Ussing chamber and HPLC. Bioactivity tests of the formulations were carried out by using the resazurin method on M. bovis cells. RESULT AND DISCUSSION: Spray rate and inlet temperature were the two most important factors that affected the size and % yield of the product. The % cell viability of A549 cells with all EDH formulations, pure EDH and chitosan carrier was higher than 80%, the calu-3 cell line had % viabilities of between 85 and 99%, and the % viability of NR8383 cells was between 81 and 100%. The pure EDH had a minimum inhibitory concentration (MIC) of 2 µg/mL while the EDH formulations had MIC values of less than 1 µg/mL when tested against M. bovis. The formulation was completely phagocytized by the macrophage cells after 30 min. The permeability of pure EDH across lipid bilayer was 48.7% after 2 h while in the EDH formulations it was enhanced to 71%. CONCLUSION: The EDH formulations showed a lower toxicity, higher potency and better permeation than the pure EDH. Thus, EDH DPI formulations could help to minimize the duration of treatment and the risk of developing multidrug resistance tuberculosis compared to the non-formulated EDH.

Evaluation of the wound healing property of Boesenbergia longiflora rhizomes.

ETHNOPHARMACOLOGICAL RELEVANCE: The rhizomes of Boesenbergia longiflora (Wall.) Kuntze (Zingiberaceae) have been traditionally used for treatment of inflammatory bowel disease, ulcerative colitis, aphthous ulcer and abscess by decoction with alcohol. AIM OF THE STUDY: The rhizomes of Boesenbergia longiflora were carried out to investigate for anti-inflammatory and wound healing activities in order to support the traditional use. MATERIAL AND METHODS: The ethanolic extract of Boesenbergia longiflora and its fractions were tested using relevant in vitro anti-inflammatory and wound healing assays. For the in vitro studies, murine macrophage RAW264.7 cells and mouse fibroblast L929 cells were assessed for anti-inflammatory and fibroblast stimulatory activities, respectively. In vivo anti-inflammatory activity was determined by carrageenan-induced rat paw edema model as well as acute toxicity estimated by the up-and-down method in mice. RESULTS: The present study has demonstrated that the ethanolic extract of Boesenbergia longiflora rhizomes possesses a potent anti-inflammatory and wound healing activities. Among the isolated fractions, the CHCl3 fraction showed potent anti-inflammatory effect through nitric oxide inhibitory activity (IC50=5.5 µg/ml) and reduction of carrageenan-induced rat paw edema (ED50=222.7 mg/kg), whereas this fraction exhibited wound healing property via fibroblast migration on both day 1 (77.3%) and day 2 (100%) as well as enhanced collagen production (187.5 µg/ml) at concentration of 3 µg/ml, compared to that of the controls, 39.4% for fibroblast and 60.8 µg/ml for collagen, respectively. The anti-inflammatory mechanism of the CHCl3 fraction is found to suppress the iNOS and COX-2 mRNA expression. CONCLUSION: The scientific investigation of wound healing activity of Boesenbergia longiflora rhizomes support the Thai traditional uses for treatment of inflammatory bowel disease, ulcerative colitis, aphthous ulcer and abscess. The EtOH extract and CHCl3 fraction exert potential wound healing property through NO inhibition, anti-oxidant effect and stimulation of fibroblast migration and collagen production. The phytochemical screening revealed that the CHCl3 fraction of Boesenbergia longiflora rhizomes contains diarylheptanoids, flavonoids and terpenes. The isolation of the compounds responsible for the wound healing effect is now in progress.

Inhaled pyrazinamide proliposome for targeting alveolar macrophages.

OBJECTIVE: In this study, pyrazinamide (PZA)-proliposome in a dry powder aerosol form was developed for delivering drugs to alveolar macrophages (AMs) infected with mycobacteria. MATERIALS AND METHODS: PZA-proliposomes consisting of pyrazinamide, soybean phosphatidylcholine, cholesterol and porous mannitol were prepared by a spray drying method. The PZA-proliposome physicochemical properties were determined using a cascade impactor, X-ray diffraction, differential scanning calorimetry and infrared spectroscopy. The toxicity of proliposomes to respiratory-associated cell lines (Calu-3, A549 and NR8383) and its potential to provoke immunological responses from AMs were determined. In vivo repeated dose toxicity in rats was evaluated. RESULTS AND DISCUSSION: PZA-proliposomes were successfully prepared. For the aerosolization properties of PZA-proliposomes at 60 l/min, the powders showed mass median aerodynamic diameters of 4.26-4.39 µm, with fine particle fractions (aerosolized particles less than 4.4 µm) of 20-30%. Encapsulation of PZA was 26-45%. PZA-proliposomes were less toxic to respiratory-associated cells, and did not activate AMs to produce inflammatory mediators, including interleukin-1ß, tumor necrosis factor-α, and nitric oxide, at a toxic level. Renal and liver toxicity in rats were not observed. CONCLUSIONS: We suggest that PZA-proliposomes are potential candidates for pulmonary tuberculosis treatment.

Wound healing activity of ent-kaura-9(11),16-dien-19-oic acid isolated from Wedelia trilobata (L.) leaves.

Wedelia trilobata (L.) Hitchc (Asteraceae) has been used in traditional medicine in the Caribbean and Central America for stubborn wounds, sores, swelling, arthritic painful joints. The present study was carried out to derive bioactive compounds from ethanolic extracts of W. trilobata (L.) leaves that could influence wound healing. W. trilobata leaves extract were subjected to bioassay-guided fractionation. The five fractions (WEA1-A, B, C, D, and E) obtained were tested for antimicrobial activity. Out of the five fractions only the fraction (WEA1-B) containing ent-kaura-9(11),16-dien-19-oic acid showed promising antibacterial activity with MIC value of 15.62µg/ml against S. aureus and 7.81µg/ml against S. epidermidis. It was then further assessed for its possible activity on fibroblasts by measuring their percentage cell viability and on oxidative stress induced by hydrogen peroxide. WEA1-B (2.5-0.08µg/ml) produced an increase in the percentage viability of mouse fibroblast L929 cells from 97 to 117% and protection of the fibroblast L929 cells against oxidative stress induced by hydrogen peroxide (94-80%). The present study provides some scientific evidence for the traditional use of W. trilobata in the management of wound healing due to a combination of antimicrobial, stimulation of fibroblast growth and protection of the cells from hydrogen peroxide-induced injury, all of which could play some role in its effect on tissue repair.

Evaluation of the wound healing potential of Wedelia trilobata (L.) leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Wedelia trilobata (L.) Hitchc (Asteraceae) leaves are used in the treatment of wounds by traditional healers. Despite the use of this plant in wound healing, there is a scarcity of scientific data to support its therapeutic application. AIM OF THE STUDY: To investigate the wound healing potential of Wedelia trilobata (L.) leaves commonly employed by traditional healers and to clarify its traditional use in a scientific investigation. MATERIALS AND METHODS: An ethanolic extract of Wedelia trilobata leaves was subjected to column chromatography. Hexane, ethyl acetate (WEA) and chloroform:methanol (50:50) (WCM) fractions were obtained. The fractions were tested using relevant in vitro wound healing assays. Antioxidant activity was measured by the DPPH assay. The fibroblast proliferation, oxidative stress using hydrogen peroxide, an in vitro scratch assay, and increasing collagen content was determined using fibroblast L929. Minimum inhibitory concentrations (MICs) were determined against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa. RESULTS: WEA (3 µg/mL) promoted fibroblast L929 survivability up to more than 90% before and more than 85% after hydrogen peroxide induced oxidative stress. WEA (3 µg/mL) induced a 70% migration rate in the in vitro scratch assay and the collagen content was increased to 261 µg/mL compared to the control (57.5 µg/mL). WCM exhibited a scavenging activity for DPPH with an IC(50) value of 179.5 µg/mL comparable to BHT (139.3 µg/mL). WEA was active against gram positive bacteria Staphylococcus aureus, Staphylococcus epidermidis with MIC values of 62.5 and 31.25 µg/mL, respectively. CONCLUSION: These scientific findings of wound healing activity supports the traditional claims for Wedelia trilobata (L.) leaves. The WEA displayed antibacterial and fibroblast stimulatory activities while WCM exhibited antioxidant to indicate its potential wound healing properties. However further studies to isolate the antibacterial, antioxidant and fibroblast stimulatory compounds that contribute to the wound healing properties of this plant are needed.

Levofloxacin-proliposomes: opportunities for use in lung tuberculosis.

Levofloxacin (LEV) is a relatively new-generation fluoroquinolone antibiotic that has good activity against Mycobacterium tuberculosis. The aims of this study were to develop and evaluate LEV-proliposomes in a dry powder aerosol form for pulmonary delivery. LEV-proliposomes containing LEV, soybean phosphatidylcholine, cholesterol and porous mannitol were prepared by a spray drying technique. The physicochemical properties of LEV-proliposomes were determined using a cascade impactor, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). The toxicity of proliposomes to respiratory-associated cell lines and its potential to provoke immunological responses from alveolar macrophages (AMs) were evaluated. Antimycobacterial activity using flow cytometry and an in vivo repeated dose toxicity test in rats were carried out. LEV-proliposomes were successfully prepared with mass median aerodynamic diameters of 4.15-4.44 µm and with fine particle fractions (aerosolized particles of less than 4.4 µm) of 13%-38% at 60 L/min. LEV-proliposomes were less toxic to respiratory-associated cells than LEV, and did not activate AMs to produce inflammatory mediators that included interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and nitric oxide. The minimum inhibitory concentration (MIC) against M. bovis of LEV and LEV-proliposomes containing LEV 10% were 1 and 0.5 µg/mL, respectively. The efficacy of LEV-proliposomes against M. bovis was significantly higher than that of free LEV (p < 0.05). The efficacy of the LEV-proliposomes against M. tuberculosis was equal to that of the free LEV (MIC = 0.195 µg/mL). In a repeated dose toxicity study in rats, renal and liver toxicity was not observed. LEV-proliposomes should now be tested as an alternative formulation for delivering LEV to the lower airways.

The effect of sericin from various extraction methods on cell viability and collagen production.

Silk sericin (SS) can accelerate cell proliferation and attachment; however, SS can be extracted by various methods, which result in SS exhibiting different physical and biological properties. We found that SS produced from various extraction methods has different molecular weights, zeta potential, particle size and amino acid content. The MTT assay indicated that SS from all extraction methods had no toxicity to mouse fibroblast cells at concentrations up to 40 mug/mL after 24 h incubation, but SS obtained from some extraction methods can be toxic at higher concentrations. Heat-degraded SS was the least toxic to cells and activated the highest collagen production, while urea-extracted SS showed the lowest cell viability and collagen production. SS from urea extraction was severely harmful to cells at concentrations higher than 100 mug/mL. SS from all extraction methods could still promote collagen production in a concentration-dependent manner, even at high concentrations that are toxic to cells.