Fuente: Foods - Revista científica (MDPI) Foods, Vol. 15, Pages 1844: Isolationof PASN from Argentine Squid Carcass By-Products Enhances Proliferation and Repair of hACs and PC12 In Vitro via Antioxidant Activity
Foods doi: 10.3390/foods15111844
Authors:
Haoze Yang
Tianming Wang
Yaqi Kong
Qian Yao
Huiying Wang
Bailin Li
Jeevithan Elango
Wenhui Wu

Marine by-products represent a promising source of bioactive peptides. This study aimed to isolate and characterize a low-molecular-weight peptide fraction with antioxidant activity from Argentine shortfin squid carcass by-products, and to evaluate in vitro its cytocompatibility and protective effects against corticosterone (CORT)-induced oxidative injury in rat adrenal pheochromocytoma (PC12) cells and human astrocyte (hACs) cells. Argentine squid antioxidant peptide (PASN) was obtained by size-exclusion chromatography and fractionation-based screening. PASN exhibited the strongest overall free-radical-scavenging activity and consisted predominantly of components below 1 kDa (211.73–1013.48 Da). Spectroscopic analyses indicated that enzymatic hydrolysis transformed its structure from a rigid triple-helix conformation to a more flexible conformation dominated by β-turns (50.78%) and random coils (17.38%). In addition, thermogravimetric analysis confirmed its excellent thermal stability, with an onset decomposition temperature as high as 244.81 °C, supporting its potential applicability in high-temperature food-processing matrices. In vitro assays demonstrated that PASN exhibited high biocompatibility and promoted proliferation of both PC12 cells and hACs, while significantly improving cell viability under CORT challenge. PASN also reduced lactate dehydrogenase (LDH) leakage (hACs: 38.31%; PC12: 31.17%) in both cell models and restored total superoxide dismutase (T-SOD) activity (hACs: 69.46%, PC12: 66.40%). Immunofluorescence further revealed that PASN rescued the expression of brain-derived neurotrophic factor (BDNF) (hACs: 35.23%, PC12: 12.50%) and glutamate decarboxylase (GAD1/2) (hACs: 102.66%, PC12: 31.31%), key markers associated with synaptic plasticity and GABAergic sleep regulation. Collectively, PASN is a thermally stable squid-derived peptide fraction that exerts antioxidant and cytoprotective effects in neural cell models in vitro and represents a promising sustainable candidate for nutraceutical development.