Therapeutic and cosmeceutical role of glycosylated natural products in dermatology.

Natural products (NPs) remain the primary source of pharmacologically active candidates for drug discovery. Since time immemorial, NPs have attracted considerable attention because of their beneficial skin effects. Moreover, there has been a great interest in using such products for the cosmetics industry in the past few decades, bridging the gap between modern and traditional medicine. Terpenoids, Steroids, and Flavonoids having glycosidic attachment have proven biological effects with a positive impact on human health. NPs derived glycosides are mainly found in fruits, vegetables, and plants, and most of them have a special reverence in traditional and modern medicine for disease prevention and treatment. A literature review was performed using scientific journals, Google scholar, Scifinder, PubMED, and Google patents. These scientific articles, documents, and patents establish the significance of glycosidic NPs in the areas of dermatology. Considering the human inclination to the usage of NPs rather than synthetic or inorganic drugs (especially in the area of skin care), in the present review we have discussed the worth of NP glycosides in beauty care and skin-related therapeutics and the mechanistic pathways involved.

Glycyrrhizic acid prevents ultraviolet-B-induced photodamage: a role for mitogen-activated protein kinases, nuclear factor kappa B and mitochondrial apoptotic pathway.

Glycyrrhizic acid (GA), a natural triterpene, has received attention as an agent that has protective effects against chronic diseases including ultraviolet UV-B-induced skin photodamage. However, the mechanism of its protective effect remains elusive. Here, we used an immortalized human keratinocyte cell line (HaCaT) and a small animal model (BALB/c mice), to investigate the protective effects of GA against UV-B-induced oxidative damage, and additionally, delineated the molecular mechanisms involved in the UV-B-mediated inflammatory and apoptotic response. In the HaCaT cells, GA inhibited the UV-B-mediated increase in intracellular reactive oxygen species (ROS) and down-regulated the release of pro-inflammatory cytokines interleukin (IL)-1α, -1ß and -6, tumor necrosis factor (TNF)-α and prostaglandin E2 (PGE2). GA inhibited UV-B-mediated activation of p38 and JNK MAP kinases, COX-2 expression and nuclear translocation of NF-κB. Furthermore, GA inhibited UV-B-mediated apoptosis by attenuating translocation of Bax from the cytosol to mitochondria, thus preserving mitochondrial integrity. GA-treated HaCaT cells also exhibited elevated antiapoptotic Bcl-2 protein, concomitant with reduced caspase-3 cleavage and decreased PARP-1 protein. In BALB/c mice, topical application of GA on dorsal skin exposed to UV-B irradiation protected against epidermal hyperplasia, lymphocyte infiltration and expression of several inflammatory proteins, p38, JNK, COX-2, NF-κB and ICAM-1. Based on the above findings, we conclude that GA protects against UV-B-mediated photodamage by inhibiting the signalling cascades triggered by oxidative stress, including MAPK/NF-κB activation, as well as apoptosis. Thus, GA has strong potential to be used as a therapeutic/cosmeceutical agent against photodamage.

Isolation, cytotoxic evaluation, and simultaneous quantification of eight bioactive secondary metabolites from Cicer microphyllum by high-performance thin-layer chromatography.

Chemical investigation of Cicer microphyllum resulted in the isolation and characterization of eight natural products viz. Stigmasterol, Oleanolic acid-3-acetate, Oleanolic acid, Biochanin A, Genistein, Pratensein, Chrysoeriol, and Luteolin. Herein, we report a novel, accurate, and cost-effective high-performance thin-layer chromatography method for the simultaneous quantification of the isolated natural products on silica-gel 60F254 plates using the solvent system n-hexane/ethyl acetate/formic acid (9.0:6.5:0.8, v/v/v). Natural products were quantified after postchromatographic derivatization with ceric ammonium sulfate. The method was validated as per the International Conference on Harmonization guidelines. All calibration curves showed a good linear relationship (r > 0.9943) within the test range. Precision was assessed by intra- and interday tests with relative standard deviations <1.82%, accuracy validation recovery 98.38-99.57% with relative standard deviations <1.00%. On quantification, Pratensein was a major constituent (0.921%). The screening for cytotoxic activity using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay resulted into identification of Luteolin as potent molecule with IC50 3.5 and 25.6 µg/mL against murine melanoma and human epidermoid carcinoma cell lines, respectively.

Simultaneous quantification of eight bioactive secondary metabolites from Codonopsis ovata by validated high performance thin layer chromatography and their antioxidant profile.

Chemical investigation of Codonopsis ovata resulted in the isolation and identification of ß-sitosterol-3-O-glycoside, luteolin, apigenin, gentiacaulein, swertiaperenine, ß-sitosterol, taraxeryl-3-acetate, and 3ß-acetoxyoleanane-12-one. A rapid, precise, sensitive and validated HPTLC method for simultaneous quantification of these natural products (NPs) was developed on silica-gel 60F254 plate using ternary solvent system, n-hexane:ethyl acetate:formic acid (10.5:3.5:0.43, v/v/v). Markers were quantified after post chromatographic derivatization with cerric ammonium sulfate reagent. The method was validated for accuracy, precision, LOD, LOQ and all calibration curves showed a good linear relationship (r>0.9924) within test range. Precision was evaluated by intra- and inter-day tests with RSDs <2.59%, accuracy validation recovery 92.43-99.50% with RSDs <1.00%. Apigenin was found major component (natural abundance: 1.103%) and ß-sitosterol the least (0.0263%). The NPs displayed antioxidant activity with luteolin exhibiting maximum effect at 1µg/mL concentration (75.9% for DPPH and 43.7% for ABTS) and others at 10 and 25µg/mL, suggesting thereby their apparent potential use for the prevention of free radical induced diseases or as an additive element to food and pharmaceutical industry.

Isolation, cytotoxicity evaluation and HPLC-quantification of the chemical constituents from Artemisia amygdalina Decne.

The hexane extracts of both shoot and root parts of Artemisia amygdalina Decne displayed potent cytotoxic effects. Phytochemical analysis of these active extracts led to the isolation of six cytotoxic constituents, viz., Ergostadien-3ß-ol (1), ludartin (2), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (3) (from shoot) and trans-matricaria ester (4), diacetylenic spiroenol ether (5) and cis-matricaria ester (6) (from root) for the first time from this plant. The constituents were identified using spectral techniques in the light of literature. Sulphorhodamine B cytotoxicity screening of the isolated constituents was carried out against four human cancer cell lines including Lung (A-549), Leukaemia (THP-1), Prostate (PC-3) and Colon (HCT-116) cell lines. Ludartin (2) exhibited the highest cytotoxicity with IC50 values of 7.4µM, 3.1µM, 7.5µM and 6.9µM against Lung (A-549), Leukaemia (THP-1), Prostate (PC-3), Colon (HCT-116) cancer cell lines respectively. To test against in vitro skin cancer models [human dermal fibroblasts (CRL-1635)] all the isolates were further subjected to 3-(4,5-Dimethylthiazol-yl)-diphenyl tetrazolium bromide (MTT) cytotoxicity screening. Ludartin (2) being highly cytotoxic was again evaluated against mouse melanoma (B16F10) and human epidermoid carcinoma (A-431) cells by MTT assay displaying IC50 values of 6.6µM and 19.0µM respectively. Finally a simple and reliable HPLC method was developed (RP-HPLC-DAD) and validated for the simultaneous quantification of these cytotoxic constituents in A. amygdalina Decne. Excellent specificity and high linearity for all the standard calibration curves having regression coefficients of the respective linear equations in the range of 0.9962-0.9999 was observed. Relative recovery rates varied between 98.37±0.90 and 105.15±1.74 with relative standard deviation less than 4%. Based on our results, the developed method features good quantification parameters, accuracy, precision and can serve as effective quality control method for standardisation of A. amygdalina Decne.

A validated high-performance thin-layer chromatography method for the identification and simultaneous quantification of six markers from Platanus orientalis and their cytotoxic profiles against skin cancer cell lines.

Betulinic acid (1), betulinic acid-3-acetate (2), 3-acetylbetulinaldehyde (3), oleanolic acid-3-acetate (4), 3-ß-hydroxy-28,19-ß-olenolide (5), and ß-sitosterol (6) were isolated from Platanus orientalis and a high-performance thin-layer chromatography method was developed for their simultaneous quantification. The markers were first derivatized on the chromatogram with ceric ammonium sulfate and then high-performance thin-layer chromatography densitometry was carried out. Chromatographic separation of these markers was carried out on silica gel 60 plates using a ternary solvent system n-hexane/toluene/acetone (6:3.5:1 v/v/v) as a mobile phase. For marker 1, a deuterium (D2) lamp and wavelength of 420 nm was used. A tungsten (W) lamp was used for markers 2 and 3 at 550 nm and for 4-6 at 500 nm. The method was validated for accuracy, precision, LOD, and LOQ. All calibration curves showed a good linear relationship (r > 0.9919). The precision evaluated by an intra- and interday study showed RSDs < 2.51% and accuracy validation recovery between 95.54 and 99.33% with RSDs < 1.55%. The successful application of the validated method showed 1 as the most abundant component (4.63%) and 5 (0.017%) the least. The markers displayed a significant cytotoxic effect against human keratinocyte, mouse melanoma, and human skin epithelial carcinoma cancer cells by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

Effect of N-acetyl cysteine (NAC), an organosulfur compound from Allium plants, on experimentally induced hepatic prefibrogenic events in Wistar rat.

Aim of present study was to investigate the effect of NAC on experimental chronic hepatotoxicity models induced by carbon tetrachloride (CCl4) and thioacetamide (TAA). CCl4 toxicity was induced by administering 200 µl CCl4 (diluted 2:3 in coconut oil)/100 g body weight, p.o., twice weekly for 8 weeks. TAA toxicity was induced by administering 150 mg/kg b. wt. of TAA i.p., twice weekly for 8 weeks. NAC treatment was started along with toxicants (CCl4 and TAA) for 8 weeks and continued for further 4 weeks. Self reversal group was kept without any treatment for 4 weeks after completion of toxicant treatments. Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Alkaline phosphatase (ALP), Bilirubin were measured in serum. Hydroxyproline (HP), lipid peroxidation (LPO), catalase (CAT), Glutathione peroxidase (GPx) and Glutathione (GSH) were determined in liver samples by colorimetric methods. Cytochrome P450 2E1 (CYP 450 2E1), activity was determined as hydroxylation of aniline in liver microsomes. General examination and histological analysis were also performed. Serum markers of liver damage (AST, ALT, ALP and Bilirubin) were increased by CCl4 and TAA intoxication (p<0.001), whereas co-treatment with NAC reversed such changes (p<0.001). HP was enhanced in toxicant groups (p<0.001 in CCl4 and TAA), but inhibited by NAC (p<0.001). LPO was increased while as GSH, CAT and GPx decreased by the administration of CCl4 and TAA (p<0.001); co-administration of NAC restored these liver markers to normal levels (p<0.001). Biochemical determinations were corroborated by general and histological findings. Keeping in view the biochemical and histopathological studies, it was concluded that CCl4 and TAA are strong hepatotoxic agents that produce liver fibrosis with close proximity to human etiology (micronodular cirrhosis) and NAC has a significant protective activity against CCl4 and TAA. NAC has also been validated as a model against oxidative burden in chronic liver pathology.

Effect of Emblica officinalis (fruit) against UVB-induced photo-aging in human skin fibroblasts.

ETHNOPHARMACOLOGICAL RELEVANCE: Emblica officinalis fruit (EO), commonly known as Amla is a reputed traditional medicine and functional food used in Indian subcontinent. It has long been used in Indian folk medicine to treat liver diseases, stomach ulcers, inflammatory diseases, metabolic disorders, geriatric complaints, skin disorders and beauty care. AIM OF THE STUDY: Recently, it has been shown to promote pro-collagen content and inhibit matrix metalloproteinase levels in skin fibroblast. The aim of the present study was to investigate the efficacy of EO to inhibit UVB-induced photo-aging in human skin fibroblasts. MATERIALS AND METHODS: Mitochondrial activity of human skin fibroblasts was measured by MTT-assay. Quantifications of pro-collagen 1 and matrix metalloproteinase 1 (MMP-1) release were performed by immunoassay techniques. Hyaluronidase inhibition assay was studied in vitro using bovine testicular hyaluronidase and human umbilical cord hyaluronic acid. Cell cycle analysis was performed by flowcytometry using propidium iodide. RESULTS: EO stimulated, the otherwise UVB inhibited cellular proliferation and protected pro-collagen 1 against UVB-induced depletion via inhibition of UVB-induced MMP-1 in skin fibroblasts (10-40 µg/mL, p>0.001). EO exhibited inhibitory activity of hyaluronidase (10-40 µg/mL, p>0.001). Treatment with EO also prevented UVB disturbed cell cycle to normal phase. CONCLUSION: The results of the present study suggests that EO effectively inhibits UVB-induced photo-aging in human skin fibroblast via its strong ROS scavenging ability and its therapeutic and cosmetic applications remain to be explored.