Preventive effect of Nile tilapia hydrolysate against oxidative damage of HepG2 cells and DNA mediated by H2O2 and AAPH

Abstract

Antioxidant activities of protein hydrolysate prepared from Nile tilapia protein isolate using Alcalase (HA), Alcalase followed by papain (HAPa) and their Sephadex G-25 fractions (FHA and FHAPa) were investigated in both chemical and cellular based models. Amongst all samples, FHAPa showed the highest chemical antioxidant activities, however it had no metal chelation activity. Cellular antioxidant ability of HA, HAPa and their fractions against H 2 O 2 and AAPH induced oxidative damage of HepG2 cell and DNA were tested. When cells were pretreated with all hydrolysates or fractions at different concentrations (0.5-2 mg/mL) in the absence and presence of 50 μM Trolox, cell viability was in the range of 91.10-111.40 %. However, no difference in cell viability was observed among samples having various concentrations (P>0.05). Cell reactive oxygen species (ROS) generation as mediated by H 2 O 2 and AAPH decreased with treatment of hydrolysates or their fractions, especially in combination with 50 μM Trolox. FHAPa effectively inhibited H 2 O 2 and peroxyl radical induced DNA scission in a dose dependent manner. Therefore, Nile tilapia protein hydrolysates could serve as a functional food ingredient.

Antioxidant Activity of Oat Proteins Derived Peptides in Stressed Hepatic HepG2 Cells

“…The tested peptides, by acting as scavengers, maintained higher cellular GSH concentration. Other studies also found that the increase of ROS due to AAPH was attenuated after treatment with peptides VCSV and CAAP from fish, and tilapia hydrolysate in rat macrophage RAW 264.7 cells [37] or HepG2 cells [38]. …”

Purification and identification of antioxidative peptides from mackerel (Pneumatophorus japonicus) protein

“…The volume of the soluble fraction was recorded, and the total nitrogen in the supernatant was determined using the Kjeldahl method. 21 23 The HepG2 cells were seeded into 96-well culture plates (4 Â 10 3 -1 Â 10 4 per well) and incubated at 37 C in a humidied atmosphere with 5% CO 2 for 24 h. Next, the HepG2 cells were incubated with H 2 O 2 or MPH at various concentrations (100 mL) for another 24 h, and the HepG2 cells without H 2 O 2 or MPHs were used as a negative control. Aer that step, each well was added 20 mL of MTT (5 mg mL À1 ) and incubated for 3 h. Aer the removal of MTT, dimethyl sulfoxide (DMSO) (150 mL per well) was added, and the mixture was shaken for 10 min.…”

“…When the cells were exposed to oxidative stressors, the viability of cells decreased. 23 As shown in Fig. 1B 1000 mM H 2 O 2 that led to 50% cell viability was selected to study the cellular antioxidant activity.…”

Antihypertensive properties of tilapia (Oreochromis spp.) frame and skin enzymatic protein hydrolysates

“…Enzymatic hydrolysates of tilapia muscle containing nearly 40% hydrophobic amino acids [5] showed antioxidant [6] and antihypertensive properties [7]. The preventive effect of tilapia hydrolysate against oxidative damage in HepG2 cells and the protective ability against DNA damage have also been reported [8]. In addition to the antioxidant and angiotensin converting enzyme (ACE)-inhibitory activities of tilapia frame [9] and skin gelatin [10] hydrolysates, tilapia protein hydrolysates also exhibited antibacterial activities [11].…”