Shilajit is a resinous blackish-brown sticky tar-like herbomineral exudate that seeps from sedimentary rocks of steep mountainous regions and has reported medicinal properties (1, 2). Although geographic and environmental factors determine the composition of shilajit (1, 3), chemical characterization of shilajit has revealed the presence of three major components as represented by dibenzo-α-pyrones (DBPs, also known as urolithins in free form as well as conjugated with chromoproteins), fulvic acid with DBP core nucleus, and humic acid (2, 3). Shilajit and its active constituents have been reported to possess an array of pharmacological properties including adaptogenic, antioxidant, anti-inflammatory, immunomodulatory, anti-diabetic, and neurological properties (4, 5).
Skin aging is characterized by wrinkles, dryness, laxity, thinning, irregular pigmentation, and loss of elasticity (6). Decrease in dermal thickness and vascularity is a hallmark of cutaneous aging (7). Aging is associated with decreased cutaneous perfusion (8). Dietary supplements show promise in preventing and managing serious health conditions. The present study was aimed at determining the effect of supplementing with a standardized shilajit extract on skin gene expression profile and related function.
The study design comprised six total study visits including a baseline visit (V1) and a final 14-week visit (V6) following oral shilajit supplementation (125 or 250 mg bid). A skin biopsy of the left inner upper arm of each subject was collected at visit 2 and visit 6 for gene expression profiling using Affymetrix Clariom™ D Assay. Skin perfusion was determined by MATLAB processing of dermascopic images. Transcriptome data were normalized and subjected to statistical analysis. The differentially regulated genes were subjected to Ingenuity Pathway Analysis (IPA®). The expression of the differentially regulated genes identified by IPA® were verified using real-time polymerasechain reaction (RT-PCR).
Supplementation with shilajit for 14 weeks was not associated with any reported adverse effect within this period. At a higher dose (250 mg bid), shilajit improved skin perfusion when compared to baseline or the placebo. Pathway analysis identified shilajit-inducible genes relevant to endothelial cell migration, growth of blood vessels, and ECM which were validated by quantitative real-time polymerasechain reaction (RT-PCR) analysis.
This work provides maiden evidence demonstrating that oral shilajit supplementation in adult healthy women induced genes relevant to endothelial cell migration and growth of blood vessels. Shilajit supplementation improved skin microperfusion.