N-Terminal Acetylation and C-Terminal Amidation of Spirulina platensis-Derived Hexapeptide: Anti-Photoaging Activity and Proteomic Analysis

Abstract

Ultraviolet (UV) irradiation is a potent inducer for skin photoaging. This paper investigated the anti-photoaging effects of the acetylated and amidated hexapeptide (AAH), originally identified from Spirulina platensis, in (Ultraviolet B) UVB-irradiated Human immortalized keratinocytes (Hacats) and mice. The results demonstrated that AAH had much lower toxicity on Hacats than the positive matrixyl (81.52% vs. 5.32%). Moreover, AAH reduced MDA content by 49%; increased SOD, CAT, and GSH-Px activities by 103%, 49%, and 116%, respectively; decreased MMP-1 and MMP-3 expressions by 27% and 29%, respectively, compared to UVB-irradiated mice. Employing isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics, 60 differential proteins were identified, and major metabolic pathways were determined. Network analysis indicated that these differential proteins were mapped into an interaction network composed of two core sub-networks. Collectively, AAH is protective against UVB-induced skin photoaging and has potential application in skin care cosmetics.

New Insights Into the Skin Microbial Communities and Skin Aging

“…Intrinsic skin aging is associated with the variation of immune homeostasis and defective barrier function (Zeng et al, 2019), so the immune-microbial alliance is also a vital factor that regulates the intrinsic aging process. We found significant enrichment of Staphylococcus in the youth and middle-aged groups, which would potentially maintain the integrity and healthy status of the skin immune barrier to further affect intrinsic aging.…”

Ameliorative Effects of Peptides from the Oyster (Crassostrea hongkongensis) Protein Hydrolysates against UVB-Induced Skin Photodamage in Mice

“…However, this method of applying oyster may limit the absorption of macromolecular nutrients, such as peptides [24]. At the same time, increasing evidences indicated that topical application of peptides on skin would hydrate the stratum corneum, increase permeability, and enhance drug absorption, eventually shortening the reaction time [24,25]. Thus, it is important to evaluate the ability and efficiency of topical application of peptides from the protein hydrolysates of oyster (Crassostrea hongkongensis) in a UVB-induced photodamaged mouse model.…”

“…UVB has been thought to be responsible for the damaging effects in the skin. Therefore, an array of eight UVB lamps (9 W with an emission spectrum between 285 and 350 nm peaked at 310-315 nm, Philips) were used for the construction of the photoaged skin animal model in this study according to previous studies with slight modification [7,25]. Briefly, an array of eight UVB lamps were positioned 16 cm above the floor of a designed apparatus for irradiation.…”

“…All dorsal skin samples were divided into three parts (an area of 1.0 × 1.0 cm). One part (0.2 g) was quickly cut and precisely weighed for the moisture content test, referring to the previous literature method [25]. Another part was fixed with paraformaldehyde for at least 24 h, dehydrated in a series of graduated ethanol, and embedded in paraffin for future histopathologic detections, while the third part was frozen promptly with liquid nitrogen and kept in a −80 • C refrigerator for further ELISA and Western blotting test.…”

Potential application of Spirulinain dermatology

“…platensis , 25 this hexapeptide decreased the expression of MMP‐1 and MMP‐3. In all analyzes, the action of AAH was superior to that of the positive control with matrixyl, a common active used as anti‐aging agent in cosmetics 27 …”