Anti-inflammatory and wound healing effects of mouth gel containing kaempulchraol K from Kaempferia galanga rhizomes.

ETHNOPHARMACOLOGICAL RELEVANCE: Kaempferia galanga L. is one of the important medicinal plants and has been used in Thailand for treating inflammation and wound. AIM OF THE STUDY: This study aimed to investigate the efficacy of the compound from K. galanga on wound healing and anti-inflammatory activities and develop a new product in gel form to maximize the benefits of this plant. MATERIALS AND METHOD: The mouth gel containing kaempulchraol K (KG2) was prepared by using 1.5% carbopol 934 as a gelling agent. Formulations of mouth gel containing KG2 at 0.10%, 0.25%, and 0.50% w/w were evaluated for color, smell, pH values, viscosity, and separation. Also, the chemical and biological stabilities of mouth gel containing KG2 were evaluated by heating-cooling test. The anti-inflammatory activity was tested against RAW 264.7 cells nitric oxide (NO) production and wound healing assay was performed using human gingival fibroblasts (HGF). RESULTS: Compound KG2 exhibited anti-NO production with an IC50 value of 66.8 µM and the wound healing activity of compound KG2 showed cell viability in the range of 90.9-111.4%. In addition, compound KG2 at a concentration of 3 µM induced the highest proportion of cell migration on day 3 at 90.2 ± 2.4%. The mouth gel containing KG2 both before and after the heating-cooling test exhibited good consistency, with pH values in the range of 6.64-6.71 (before) and 6.63-6.68 (after). Meanwhile, the viscosity was 81,700-96,700 cP (before) and 78,300-93,300 cP (after). For the chemical stability test of the active ingredient of mouth gel, the compound showed good stability after mixing with the gel base. The mouth gel exhibited anti-inflammation with IC50 values > 1000 µg/ml both before and after accelerating conditions. The wound healing activity of mouth gel containing KG2 (0.50% w/w) showed the highest % cell viability at 128.6% (before) and 123.8% (after). For cell migration, the result suggested that the mouth gel containing KG2 at 0.10%, 0.25%, and 0.50% w/w (3 µg/ml) on day 3 enhanced cell migration higher than that of the positive controls both before (85.0-96.8%) and after (and 84.4-94.3%) the accelerating conditions. CONCLUSION: The present study shows that mouth gel containing 0.50% KG2 is the most appropriate with good physical, chemical, and biological stabilities and might be one of the alternative sources for treatment of mouth ulcers (oral stomatitis) derived from aphthous ulcers, chemotherapy, and radiotherapy treatments.

Unveiling the Properties of Thai Stingless Bee Propolis via Diminishing Cell Wall-Associated Cryptococcal Melanin and Enhancing the Fungicidal Activity of Macrophages.

Cryptococcus neoformans, a life-threatening human yeast pathogen, has the ability to produce melanin, which is one of the common virulence factors contributing to cryptococcal pathogenesis. This virulence factor is closely associated with the cryptococcal cell wall, specifically chitin and chitosan polysaccharides, a complex structure that is essential for maintaining cellular structure and integrity. In this study, we aim to investigate the effects of two stingless bee (SLB) propolis from Tetragonula laeviceps and Tetrigona melanoleuca against cell wall-associated melanin in C. neoformans, and its immune response in RAW 264.7 macrophage. The ethanolic extract of SLB propolis (EEP) has strongly exhibited anti-cryptococcal activity. Moreover, EEP from both sources reduced chitin/chitosan and melanin production against C. neoformans in a dose-dependent manner. Likewise, the mRNA expression level of CDA1, IPC1-PKC1 and LAC1 genes involved in the cryptococcal melanization pathway was significantly decreased at 2 mg/mL in EEP treatment. Additionally, pretreatment with EEP prior to yeast infection dramatically reduced intracellular replication of C. neoformans in RAW 264.7 macrophages in a dose-dependent manner. This study might be a new insight to use a natural powerful source, not only acting to target cell wall-associated molecules, but also being capable to explore a novel strategy by which dysregulation of these molecules leads to promote immunomodulatory activity.

In Vitro Antifungal and Antivirulence Activities of Biologically Synthesized Ethanolic Extract of Propolis-Loaded PLGA Nanoparticles against Candida albicans.

Propolis is a natural substance and consists of bioactive compounds, which gives it antioxidant and antimicrobial properties. However, the use of propolis is limited by the low solubility in aqueous solutions. Thus, nanoparticles may be likely to accomplish enhanced delivery of poorly water-soluble phytomedicine. The aim of the present study was to fabricate and evaluate the biological activity of ethanolic extract of propolis-loaded poly(lactic-co-glycolic acid) nanoparticles (EEP-NPs). The EEP-NPs were prepared using the oil-in-water (o/w) single-emulsion solvent evaporation technique. The physicochemical properties of EEP-NPs were characterized and tested on their cytotoxicity, antifungal activity, and impact on key virulence factors that contribute to pathogenesis of C. albicans. EEP-NPs were successfully synthesized and demonstrated higher antifungal activity than EEP in free form. Moreover, EEP-NPs exhibited less cytotoxicity on Vero cells and suppressed the virulence factors of C. albicans, including adhesion, hyphal germination, biofilm formation, and invasion. Importantly, EEP-NPs exhibited a statistical decrease in the expression of hyphal adhesion-related genes, ALS3 and HWP1, of C. albicans. The results of this study revealed that EEP-NPs mediates a potent anticandidal activity and key virulence factors by reducing the gene-encoding virulence-associated hyphal- adhesion proteins of C. albicans and, thereby, disrupting the morphologic presence and attenuating their virulence.

A potential of propolis on major virulence factors of Cryptococcus neoformans.

The present study was conducted to investigate the effects of a natural product from honeybees, named propolis, against Cryptococcus neoformans and its effect in the expression of putative virulence factors, such as capsular polysaccharides, melanin production and urease enzyme. Ethanol extract propolis (EEP) was first tested for its anti-cryptococcal activity and explored its impact on virulence factors in both phenotypes and enzyme activities. Moreover, the cryptococcal virulence genes were investigated using real time RT-PCR. The MIC value of EEP, 1 mg ml-1, displayed potent inhibition of C. neoformans cell viability. Of note is the high efficacy of sub-MIC concentrations (ranging from 0.5 to 0.125 mg ml-1) in decreasing the production of capsule, melanin, as well as laccase and urease enzyme activities. Importantly, EEP exhibited statistically decrease in the expression of gene-encoded virulence factors. In conclusion, EEP mediates C. neoformans growth inhibition and virulence factors by reducing the gene-encoding virulence-associated proteins and, thereby, disrupting the morphologic presence and attenuating their virulence. This study introduced EEP as regards anti-cryptococcal virulence factors activities; therefore, EEP would provide alternative ways of controlling the pathogenicity.