In the fields of organic chemistry, dermatology, and regenerative aesthetics, It's important to know about lactic acid. Lactic acid is a fundamental molecule with powerful implications that found naturally in the body and in fermented foods.
Lactic acid exists in two optical isomers: L-lactic acid (Levo) and D-lactic acid (Dextro). These isomers differ in the way they rotate polarized light, a subtle distinction rooted in their molecular structure but one that carries significant biological consequences. Lactic acid is generally present in low amounts in fruits, but it does occur in some fermentation processes. For example, apples and pears also produce lactic acid during the fermentation process, especially when making perry wine or pear vinegar. On the other hand, D-lactic acid is less common in nature but can be produced by certain bacteria during fermentation processes.
Poly-L-lactic acid (PLLA), a type of natural biodegradable material. It's part of the PLA (polylactic acid) family. Rather than filling the skin temporarily, PLLA stimulates your own collagen production, helping restore skin firmness and structure over time. PLLA is an FDA-approved polymer known for its low toxicity compared to other synthetic polymers such as PDLA. PLLA has higher crystallinity and stability, meaning it lasts longer and degrades more slowly.
PLLA supports the activity of epidermal stem cells (EpiSCs), which are crucial for skin renewal. It helps maintain Collagen XVII (COL17A1), a key protein in anchoring stem cells to the skin’s basement membrane. By preserving COL17A1 levels, PLLA delays skin thinning and promotes epidermal regeneration. PLLA activates fibroblasts via the p38, Akt, and JNK pathways, boosting collagen type I synthesis. Through fibroblast exosome communication, PLLA indirectly supports epidermal stem cell function, improving skin texture, density, and resilience.
Poly-D,L-lactic acid (PDLLA), a synthetic copolymer of D- and L-lactide, has been explored in aesthetic medicine. The unique properties of PDLLA, such as its ability to stimulate collagen synthesis, promote tissue regeneration, and exhibit controlled degradation rates, make it an attractive material for the treatment of various skin-related disorders.