Wound healing properties of pharmaceutical gel containing isopimarane diterpene isolated from Kaempferia galanga L

ETHNOPHARMACOLOGICAL RELEVANCE

Kaempferia galanga L. rhizomes have been widely used in Thailand as medicine for treating inflammation and wound. A number of bioactive compounds have been isolated from the rhizomes of K. galanga and these compounds exhibited various pharmacological activities.

AIM OF THE STUDY

The objective of this study is to investigate the wound healing properties of gel containing 6β-acetoxysandaracopimaradiene-1α, 9α-diol (KG6), a compound from K. galanga.

MATERIALS AND METHODS

KG6 gel formulations were prepared using 1.0% carbopol 940 as gelling agent. Three KG6 gel formulations (0.10, 0.25, 0.50% w/w) were subjected to heating-cooling test to determine their physical, chemical and biological stabilities. The wound healing properties of KG6 gel formulations were performed using RAW264.7 cells for anti-inflammatory effect, while their impact on cell proliferation and migration, collagen content and H₂O₂-induced oxidative stress was examined using human dermal fibroblasts (HDF).

RESULTS

The pH, viscosity and general appearance after the heating-cooling test of the three prepared gels were stable in the acceptable range of gel formulation for skin. Gel containing 0.25% KG6 showed better chemical stability than other formulations. The 0.25% KG6 gel significantly increased cell viability (102.8%) and produced the highest HDF cell migration (91.9%) which was greater than that of Aloe vera gel (96.2, 78.4%, respectively). This gel exhibited anti-inflammatory activity via suppressing nitric oxide release and improved the viability of HDF cells against H₂O₂-induced oxidative stress. The 0.25% KG6 gels also increased collagen content in HDF cells.

CONCLUSION

The gel formulation consisting of 0.25% KG6 with 1.0% of carbopol 940 was found to be a promising pharmaceutical gel for wound treatments due to marked wound healing properties.

Anti-inflammatory effect of isopimarane diterpenoids from Kaempferia galanga

Two new isopimarane diterpenes, 1α-hydroxy-14α-methoxyisopimara-8(9),15-diene (7) and 1α,14α-dihydroxyisopimara-8(9),15-diene (9) and eight known isopimarane diterpenes including (-)-sandaracopimaradiene (1), 6β-acetoxysandaracopimaradiene-9α-ol (2), sandaracopimaradiene-7β,9α-diol (3), sandaracopimaradiene-1α,9α-diol (4), 6β-acetoxysandaracopimaradiene-9α-ol-1-one (5), 6β-acetoxysandaracopimaradiene-1α,9α-diol (6), 6β,14α-dihydroxyisopimara-8(9),15-diene (8), and 6β,14β-dihydroxyisopimara-8(9),15-diene (10) were isolated from hexane fraction of Kaempferia galanga ethanol extract. Compounds 5, 6, 8, and 9 exerted the good anti-inflammatory effect on lipopolysaccharide-stimulated nitric oxide production from RAW264.7 cells with IC₅₀ of 11.2, 7.7, 14.3, and 12.1 μM, respectively. These four compounds inhibited nitric oxide synthase (iNOS) mRNA expression. Compounds 5 and 6 also suppressed cyclooxygenase 2 (COX-2) mRNA expression; in addition, compound 6 had mild inhibitory effect on TNF-α mRNA. Among these compounds, 5 dramatically inhibited iNOS and COX-2 mRNA expression. The influential structures were proposed to be oxygen substitute at C-1, C-6, and α-OH at C-14.

Anti-HIV-1 integrase effect of compounds from Aglaia andamanica leaves and molecular docking study with acute toxicity test in mice

CONTEXT

Acquired immunodeficiency syndrome (AIDS) is a serious health problem worldwide. It has been reported that Aglaia andamanica Hiern (Meliaceae) leaves possessed an antiviral effect. Therefore, a search of anti-HIV-1 integrase (HIV-1 IN) agents from A. andamanica is a promising target.

OBJECTIVE

The objective of this study is to evaluate anti-HIV-1 IN activity of isolated compounds from A. andamanica using an in vitro assay and molecular docking study as well as testing acute toxicity in mice using the up and down method.

MATERIALS AND METHODS

The leaves and compounds (3-100 μg/mL) from A. andamanica were determined for the anti-HIV-1 IN effect using the multiplate integration assay (MIA) by detection the absorbance of the final product, p-nitrophenol, at 405 nm. The molecular docking with the HIV-1 IN of the active compound N-methyl-trans-4-hydroxy-l-proline (10) was also studied. The Swiss albino mice were used for an acute toxicity test.

RESULTS AND DISCUSSION

Among the isolated compounds, 10 showed marked anti-HIV-1 IN effect with an IC50 value of 11.8 μg/mL, whereas other compounds were inactive (IC50 value > 100 μg/mL). The molecular docking of compound 10 with an HIV-1 IN enzyme was also studied. The result revealed that this compound formed the hydrogen bonding with the Thr66, Asn155, and Lys159 of the HIV-1 IN binding site. The acute toxicity of the A. andamanica extract was not observed at the dose 2000 mg/kg mice. This is the first report of A. andamanica for anti-HIV-1 IN activity.

Uterine relaxant effects of Curcuma aeruginosa Roxb. rhizome extracts

The effects and plausible mechanism of action of Curcuma aeruginosa Roxb. (Zingiberaceae) rhizome chloroform and methanol extracts on the uterine contraction were investigated using isolated uterus strips from estrogen primed rats. The contractile responses were recorded isometrically with a Grass FT03 force transducer connected to a MacLab system. The experiments were carried out on both nonstimulated, agonist- and KCl-stimulated uteri. In the nonstimulated uterus, the two extracts (10-400 microg/ml) had no significant effect. In contrast, in the stimulated uterus, the chloroform and methanol extracts exerted concentration-dependent inhibition of the contractions induced by oxytocin (1 mU/ml), prostaglandin F2alpha (PGF2alpha, 0.5 microg/ml), ACh (3x10(-6) M) and KCl (40 mM) with the IC50 (inhibition of force) of 31.4, 58.59, 56.21 and 29.28 microg/ml; and 57.79, 69.3, 223.8 and 69.19 microg/ml, respectively. Verapamil, the reference L-type calcium channel blocker, exhibited a similar pattern of inhibition with the IC50 of 0.03, 0.25, 0.35 and 0.04 microg/ml. The IC50 of diclofenac against a PGF2alpha-induced contraction was 31.36 microg/ml. It is known that the contraction induced by agonists and KCl is mainly due to calcium influx through the voltage-gated L-type calcium channels opened indirectly or directly by agonist-receptor activation and KCl. Thus, it is speculated that the two plant extracts might inhibit uterine contraction by interrupting the influx of Ca2+ probably through voltage-gated L-type calcium channels. This possibility was further substantiated by the ability of the extracts to shift the CaCl2-contraction curves to the right. As the methanol extract also reduced the contraction of oxytocin in Ca2+-free EDTA solution; thus, it is suggested that part of its action may be involved with an intracellular mechanism. The effect of the two extracts did not involve the activation of beta2-adrenoceptors since their effects were unaffected by propranolol. Based on the inhibitory effect of the extracts on the oxytocin-induced contraction, it is concluded that the extracts might be useful as tocolytic agents for the prevention of preterm labor. Their effects on the inhibition of PGF2alpha-induced contractions also seem useful for the treatment of dysmenorrhea. There are reports by others that the plant rhizome contains beta-pinene and sesquiterpenes. In addition, there is evidence that these compounds possess spasmolytic effects in the rat intestine and uterus. Therefore, the uterine relaxant effect of the plant extracts could be due to beta-pinene and some sesquiterpene lactones contents. The methanol extract is less potent than the chloroform extract, and this might be due to the lower amount of terpene compounds or different compounds may involve in this action.