Carnosine (beta-alanyl-L-histidine) is a naturally occurring dipeptide found in muscle and other tissues, used in cosmetics. Skin research consists mainly of ex vivo human skin and cell studies of glycation and oxidative markers.
Carnosine is studied as a scavenger of reactive carbonyls and oxygen species. In human skin explants, researchers measured lower levels of advanced glycation end-product markers (carboxymethyl-lysine, pentosidine) and reactive oxygen species after carnosine application under glycation or solar-radiation stress [1][2]. Proteomic work in fibroblast spheroids reported shifts in antioxidant enzymes and energy-metabolism pathways after UVA exposure [3]; how these lab findings translate to intact human skin is not established.
| Study | Model | Reported result | Source |
|---|---|---|---|
| Carnosine and methylglyoxal glycation [1] | Cell Ex vivo human skin explants (one donor), methylglyoxal-induced glycation | 0.2% aqueous carnosine reduced methylglyoxal-induced epidermal carboxymethyl-lysine by 64% and pentosidine by 48%; a carnosine cream also tested. | Peer-reviewed Skin Pharmacol Physiol 2018 |
| Carnosine under solar-simulated radiation [2] | Cell Ex vivo human skin biopsies, solar-simulated radiation | Carnosine reduced radiation-induced AGEs by 46% (0.2%) and 73% (2.0%), ROS by 60% (0.2%), and modulated 7 of 11 biomarker genes. | Peer-reviewed Photochem Photobiol 2024 |
| Carnosine in UVA-exposed fibroblast spheroids [3] | Cell 3D human dermal fibroblast spheroids, UVA 30 J/cm², 150 µM carnosine | Proteomics: carnosine-exposed spheroids showed higher levels than UVA-only spheroids of GST, SOD1 and thioredoxin levels at day 7 and shifted metabolic pathway scores. | Peer-reviewed Antioxidants 2023 |
| Peptide mixtures in senescent fibroblasts [4] | Cell Human skin fibroblasts, hydrogen-peroxide-induced premature senescence | Carnosine alone tested at 200 µg/mL for SOD activity; mixture including carnosine lowered malondialdehyde and raised SOD and glutathione peroxidase. | Peer-reviewed Skin Pharmacol Physiol 2021 |
Human cosmetic studies describe appearance only. Lab results do not establish effects on skin structure.
