Antioxidant and Antiapoptotic Properties of Oat Bran Protein Hydrolysates in AAPH-Induced Oxidative Stress Hepatocarcinoma HepG2
Bibliographic record
Abstract
The onset of many chronic diseases such as cancer, carcinogenesis, cardiovascular disease, and several other health problems, involves oxidative stress damage to biomolecules such as DNA, lipid, and proteins.There have been many preventative and therapeutic methods proposed to increase cellular defense mechanisms against oxidative damage such as using bioactive peptide with antioxidant activities from food sources.This study found that AAPH-induced oxidative stress in human hepatocarcinoma HepG2 cells caused changes in cellular morphological features and functionalities such as cell viability, activity of antioxidative enzymes (catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD)), production of reactive oxygen species (ROS), and rate of apoptosis.The use of oat bran protein hydrolysates restored some of the properties to normal values (i.e., control cells).In this work, oat brans were treated with two carbohydrases (Cellulase ® (Cell) and viscozyme ® L (Visc) which cleave cell wall polysaccharides and produce oat bran protein isolates (OBPIs) with protein contents.OBPI was subsequently treated with proteases Alcalase (Alca), Flavourzyme ® (Flav), Papain (Papa) and Protamex (Prot) to produce four oat bran protein hydrolysates (OBPHs) from each of oat bran protein isolate (OBPIs).Antioxidative effects of both the two OBPI and four OBPH samples were studied in chemistry and HepG2 cell cultures assays.In the chemistry assays the antioxidative activities were determined using oxygen radical absorbance capacity (ORAC), 2,2'-azino-bis (3ethylbenzothiazoline-6-sulphonic acid) or ABTS •+ , radical, hydroxyl ( • OH), and superoxide anion (O2 •-) radical scavenging assays.Data from oxygen radical absorbance capacity (ORAC) and 2,2'azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS •+ ) assays were expressed as Trolox (a water-soluble vitamin E analogue) equivalent per gram (TE/g) of the sample followed the same pattern.The highest ORAC activities were observed in Cell/Papa (417.0 ± 5.1 TE/g), Visc/Flav (406.0 ± 8.8 TE/g) and Visc/Papa (397.0 ± 13.9 TE/g) while in the ABTS •+ , highest scavenging samples were Visc/Flav and Visc/Papa (863.80 ± 20.3 and 814.8 ± 17.2 TE/g respectively).In the hydroxyl radical scavenging assay, Cellulase and Viscozyme OBPIs significantly prevented the formation of • OH, radicals 38.5 ± 0.8 and 36.0 ± 0.4%, respectively compared to all hydrolysates.iii Superoxide anion radical scavenging activity was the highest in samples Visc/Alca and Cell/Prot both at 37.3 ± 0.9%.SDS-PAGE results indicated that globulin (58 kDa) was the main protein in OPBIs and those hydrolysates did not contain protein or fragments above 15 kDa.Cytotoxicity of OBPIs and OBPHs, their ability to reduce intracellular reactive oxygen species (ROS), and regulate the activity of three main antioxidant enzymes were evaluated in the AAPH-induced oxidative stress of HepG2 cells.Cytotoxic effect OBPH was evaluated using Visc/Flav ND at 50 -400 µg/mL.No cytotoxicity was observed in MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay.In the cytoprotection assay, Viscozyme and all its OBPHs derivatives were able to increase cell viability significantly compared to stressed control HepG2 cells.However, Cellulase OBPI and its OBPHs derivatives enhanced cell HepG2 cell death, except for Cell/Flav OBPH which had no effect.OBPHs from Viscozyme treated brans and Cell/Flav OBPH were then chosen for investigation of their effects on antioxidant enzymes.In the Catalase (CAT) assay, all samples increased enzyme activity (p < 0.05) in AAPH-stressed cells, with Visc/Papa being the highest at 352.0%.In superoxide dismutase (SOD), all samples increased activity level above positive control (POS) with Visc/Flav performing significantly better than the other samples.Visc/Flav not only restored glutathione peroxidase (GPx) activity to that of negative control (NEG) (i.e., unstressed cells), it also reduced the most intracellular reactive oxygen species (ROS).Total glutathione (GSH) increased up to 6-fold in the presence of OBPH in stressed HepG2 cells.In the Caspase-3 assay for anti-apoptosis properties, samples reduced caspase-3 significantly compared to AAPH-induced oxidative stress in HepG2 cells.OBPH protected HepG2 cells from oxidative stress due to a combination of factors including radical scavenging activity, upregulation of antioxidant enzymes, and inhibition of the activity of the apoptotic enzyme caspase-3.v
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".