Centella AsiaticavsSqualane

The four key triterpenoid saponins—madecassoside, asiaticoside, madecassic acid, and asiatic acid—exert distinct but complementary mechanisms. Madecassoside and asiaticoside are anti-inflammatory: they inhibit NF-κB nuclear translocation and IκB kinase activity, reducing TNF-α, IL-6, and IL-1β production in keratinocytes and dermal cells. Madecassic acid and asiatic acid (the aglycone forms) stimulate type I and III collagen synthesis in fibroblasts by upregulating collagen gene expression and procollagen production. All four compounds promote wound healing by stimulating angiogenesis via VEGF (vascular endothelial growth factor) upregulation, fibroblast proliferation and migration, and extracellular matrix remodeling. Centella extracts also increase superoxide dismutase (SOD) and catalase activity in skin cells, enhancing endogenous antioxidant defense. The triterpenes may modulate TGF-β and Smad signaling. TECA (Titrated Extract of Centella Asiatica) standardizes these actives for consistent clinical efficacy.

Squalane is the fully hydrogenated form of squalene—a C30 isoprenoid hydrocarbon. As a saturated branched-chain hydrocarbon, squalane forms a non-occlusive emollient film that fills intercellular lipid spaces and reduces transepidermal water loss (TEWL) by approximately 20-30%. Squalene comprises ~12% of human sebum (synthesized via mevalonate pathway); squalane's structural similarity confers high biocompatibility and minimal comedogenic potential. Hydrogenation of squalene's six double bonds eliminates oxidative susceptibility—squalene peroxidizes with UV exposure while squalane remains stable. Squalane penetrates the stratum corneum and may support barrier lipid organization. Plant-derived squalane (sugarcane, olive) is structurally identical.