Anti-psoriatic effects of indigo naturalis on the proliferation and differentiation of keratinocytes with indirubin as the active component
ABSTRACT Indigo naturalis has shown efficacy in treating psoriasis in our previous clinical studies.
To investigate the potential effect of indigo naturalis on regulating keratinocyte proliferation and differentiation.
Skin samples from six patients were analyzed for proliferating cell nuclear antigen (PCNA) and involucrin expression by immunohistochemical staining. In addition, indigo naturalis extracts from 10 to 500 microg/ml were added to cultured keratinocytes and cell viability determined. Real-time RT-PCR, Western blotting analysis and indirect immunofluorescent labeling were used to investigate the messenger (m)RNA and protein expressions of PCNA and involucrin. Finally, high-performance liquid chromatography (HPLC) was used to identify major components of indigo naturalis and their in vitro effects compared.
Immunohistochemical results demonstrated decreased PCNA and increased involucrin in psoriatic lesions after indigo naturalis treatment. Cultured keratinocytes decreased after indigo naturalis treatment, while G(0)/G(1) arrest was observed to dose-dependently increase. Staining revealed decreased PCNA-stained nuclei and increased cytosolic involucrin in treated keratinocytes. Decreased PCNA and increased involucrin at both the mRNA and protein levels were confirmed. Both major components, indirubin and indigo, could cause G(0)/G(1) phase arrest; however, only indirubin modulated the expressions of PCNA and involucrin similar to indigo naturalis.
Together, these findings indicate that the anti-psoriatic effects of indigo naturalis are mediated, at least in part, by modulating the proliferation and differentiation of keratinocytes, with indirubin as the major active component.
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ABSTRACT: Treating nail psoriasis is notoriously difficult and lacks standardized therapeutic regimens. Indigo naturalis has been demonstrated to be safe and effective in treating skin psoriasis. This trial was conducted to evaluate the efficacy and safety of refined indigo naturalis extract in oil (Lindioil) in treating nail psoriasis. Thirty-one outpatients with symmetrically comparable psoriatic nails were enrolled. Lindioil (experimental group) or olive oil (control group) was applied topically to the same subjects’ two bilaterally symmetrical psoriatic nails twice daily for the first 12 weeks and then subjects applied Lindioil to both hands for 12 additional weeks. Outcomes were measured using Nail Psoriasis Severity Index (NAPSI) for five nails on one hand and for the single most severely affected nail from either hand. The results show a reduction of NAPSI scores for the 12-week treatment for the Lindioil group (49.8% for one hand and 59.3% for single nail) was superior to the reduction in the scores for the control group (22.9%, 16.3%, respectively). There were no adverse events during the 24 weeks of treatment. This trial demonstrates that Lindioil is a novel, safe and effective therapy for treating nail psoriasis.Phytomedicine: international journal of phytotherapy and phytopharmacology 06/2014; 21(7). DOI:10.1016/j.phymed.2014.02.013 · 2.97 Impact Factor
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ABSTRACT: Indirubin derivatives and analogs comprise a significant group of ATP-competitive inhibitors. The inhibitory effects of ChEMBL474807 (1-(4-amino-1,2,5-oxadiazol-3-yl)-5-(piperidin-1-ylmethyl)-N'-(pyridin-4-ylmethylene)-1H-1,2,3-triazole-4-carbohydrazide) on two enzymes, namely glycogen synthase kinase-3β (GSK-3β) and cyclin-dependent kinase-2 (CDK-2), were analyzed. The close resemblance of the amino acid sequences of these two enzymes (with 25 % identity and 41 % similarity) explains why indirubin derivatives are inhibitors of both of the enzymes studied. The docking and molecular dynamics investigation performed here led to the identification of the interactions responsible for stabilizing the ligand ChEMBL474807 at the active sites of the enzymes considered. The structural and energetic data collected during our investigations clearly indicate that there are important differences in the behavior of the ligand at the two active sites investigated here.Journal of Molecular Modeling 04/2015; 21(4):2627. DOI:10.1007/s00894-015-2627-z · 1.87 Impact Factor
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ABSTRACT: Intrinsic aging and photoaging modify skin structure and components, which subsequently change percutaneous absorption of topically applied permeants. The purpose of this study was to systematically evaluate drug/sunscreen permeation via young and senescent skin irradiated by ultraviolet (UV) light. Both young and senescent nude mice were subjected to UVA (10J/cm(2)) and/or UVB radiation (175mJ/cm(2)). Physiological parameters, immunohistology, and immunoblotting were employed to examine the aged skin. Hydroquinone and sunscreen permeation was determined by in vitro Franz cell. In vivo skin absorption was documented using a hydrophilic dye, rhodamine 123 (log P=-0.4), as a permeant. UVA exposure induced cyclooxygenase (COX)-2 and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) upregulation. Epidermal tight junction (TJ) were degraded by UVA. UVB increased transepidermal water loss (TEWL) from 13 to 24g/m(2)/h. Hyperplasia and inflammation, but not loss of TJ, were also observed in UVB-treated skin. UVA+UVB- and UVA-irradiated skin demonstrated similar changes in histology and biomarkers. UVA+UVB or UVA exposure increased hydroquinone flux five-fold. A negligible alteration of hydroquinone permeation was shown with UVB exposure. Hydroquinone exhibited a lower penetration through senescent skin than young skin. Both UVA and UVB produced enhancement of oxybenzone flux and skin uptake. However, the amount of increase was less than that of hydroquinone delivery. Photoaging did not augment skin absorption of sunscreens with higher lipophilicity, including avobenzone and ZnO. Exposure to UVA generally increased follicular entrance of these permeants, which showed two- to three-fold greater follicular uptake compared to the untreated group. Photoaging had less impact on drug/sunscreen absorption with more lipophilic permeants. Percutaneous absorption did not increase in skin subjected to both intrinsic and extrinsic aging.International Journal of Pharmaceutics 05/2014; DOI:10.1016/j.ijpharm.2014.05.034 · 3.79 Impact Factor