Ectoine is a cyclic amino acid derivative produced by bacteria living in extreme environments, which exerts cytoprotective effects through osmoregulation[1]. By binding to water molecules, ectoine forms a stable protective hydration shell around cellular components, safeguarding cell structures from damage caused by environmental factors and helping maintain the natural folding state of proteins[2]. Ectoine has been widely used in high-end skincare products, anti-allergic agents, and neuroprotection-related fields due to the compound's favorable safety profile and ability to repair cellular barriers[3,4].
In vitro, pretreatment of human red blood cells with ectoine (0-5%) for 1h protected the cells from damage induced by SDS treatment, with higher concentrations of ectoine providing stronger membrane protection[5]. When co-incubated with 25μM amyloid-β peptide (Aβ42) for 72h, ectoine (25μM-100mM) concentration-dependently reduced Thioflavin T (ThT)-induced fluorescence, indicating fewer cross-β-sheet structures. Notably, 100mM ectoine significantly inhibited Aβ42 fibril aggregation[6]. Pretreatment of human neutrophils with 1mM ectoine for 2h, followed by co-incubation with inflammatory mediators such as 300nM leukotriene B4 (LTB4) and 33μg/mL carbon nanoparticles (CNP) for 16h, significantly restored neutrophil apoptosis rates that were suppressed by these stimuli[7].
In vivo, topical administration of ectoine (0.5-2.0%; 5μL/eye; 4 times daily) in a dry eye model in C57BL/6 mice for 5 days improved corneal smoothness in a concentration-dependent manner. Both 1.0% and 2.0% ectoine restored corneal smoothness to near or complete normality[8]. A single co-administration of ectoine (1mM) with CNP (2.5mg/kg) into the lungs of Fisher 344 rats significantly reduced neutrophil counts and cinc-1 levels from 48 to 168h, demonstrating notable and sustained anti-inflammatory effects[7].
References:
[1] WANG K, CUI B, WANG Y, et al. Microbial production of ectoine: a review[J]. ACS Synthetic Biology, 2025, 14(2): 332-342.
[2] NG H S, WAN P K, KONDO A, et al. Production and recovery of ectoine: A review of current state and future prospects[J]. Processes, 2023, 11(2): 339.
[3] KAUTH M, TRUSOVA O V. Topical ectoine application in children and adults to treat inflammatory diseases associated with an impaired skin barrier: a systematic review[J]. Dermatology and Therapy, 2022, 12(2): 295-313.
[4] BUJAK T, ZAGÓRSKA-DZIOK M, NIZIOŁ-ŁUKASZEWSKA Z. Complexes of ectoine with the anionic surfactants as active ingredients of cleansing cosmetics with reduced irritating potential[J]. Molecules, 2020, 25(6): 1433.
[5] GRAF R, ANZALI S, BUENGER J, et al. The multifunctional role of ectoine as a natural cell protectant[J]. Clinics in Dermatology, 2008, 26(4): 326-333.
[6] KANAPATHIPILLAI M, LENTZEN G, SIERKS M, et al. Ectoine and hydroxyectoine inhibit aggregation and neurotoxicity of Alzheimer’s β-amyloid[J]. FEBS Letters, 2005, 579(21): 4775-4780.
[7] SYDLIK U, PEUSCHEL H, PAUNEL-GÖRGÜLÜ A, et al. Recovery of neutrophil apoptosis by ectoine: a new strategy against lung inflammation[J]. European Respiratory Journal, 2013, 41(2): 433-442.
[8] CHEN X, LIN N, LI J M, et al. Ectoine, from a natural bacteria protectant to a new treatment of dry eye disease[J]. Pharmaceutics, 2024, 16(2): 236.