Characterization of Purified Red Cabbage Anthocyanins: Improvement in HPLC Separation and Protective Effect against H2O2-Induced Oxidative Stress in HepG2 Cells

In this study, the chemical profiles and antioxidant activities of red cabbage anthocyanin (RCA)-enriched extract are evaluated. The effects of column temperature on the HPLC resolution of the RCAs are studied. The HPLC resolutions became better as the column temperature increased from 20 °C–45 °C. An optimized HPLC condition was achieved at 45 °C and used for the quantification and qualification of the RCAs. The anthocyanins in the enriched powder are all derivatives of cyanidin (268 ± 2 μg/mg), mainly with 19% nonacylated, 51% monoacylated, and 31% diacylated structures with ferulic, sinapic, p-coumaric, and caffeic acids characterized by HPLC-MS. The RCA extracts markedly reduced intracellular oxidative stress production by H2O2 on HepG2 cells and consequently ameliorated cell apoptosis and improved viability. The analytical method and cellular antioxidant activity demonstration of the RCAs will greatly facilitate their functional applications.

Download Full-text

Separation and Characterization of Phenolamines and Flavonoids from Rape Bee Pollen, and Comparison of Their Antioxidant Activities and Protective Effects Against Oxidative Stress

Molecules ◽

10.3390/molecules25061264 ◽

2020 ◽

Vol 25 (6) ◽

pp. 1264 ◽

Cited By ~ 1

Author(s):

Huifang Zhang ◽

Rui Liu ◽

Qun Lu

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Antioxidant Activities ◽

Oxygen Species ◽

Protective Effects ◽

Antioxidant Power ◽

Bee Pollen ◽

Ferric Reducing Antioxidant Power ◽

Kaempferol Glycosides

Phenolamines and flavonoids are two important components in bee pollen. There are many reports on the bioactivity of flavonoids in bee pollen, but few on phenolamines. This study aims to separate and characterize the flavonoids and phenolamines from rape bee pollen, and compare their antioxidant activities and protective effects against oxidative stress. The rape bee pollen was separated to obtain 35% and 50% fractions, which were characterized by HPLC-ESI-QTOF-MS/MS. The results showed that the compounds in 35% fraction were quercetin and kaempferol glycosides, while the compounds in 50% fraction were phenolamines, including di-p-coumaroyl spermidine, p-coumaroyl caffeoyl hydroxyferuloyl spermine, di-p-coumaroyl hydroxyferuloyl spermine, and tri-p-coumaroyl spermidine. The antioxidant activities of phenolamines and flavonoids were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assays. It was found that the antioxidant activity of phenolamines was significantly higher than that of flavonoids. Moreover, phenolamines showed better protective effects than flavonoids on HepG2 cells injured by AAPH. Furthermore, phenolamines could significantly reduce the reactive oxygen species (ROS), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and increase the superoxide dismutase (SOD) and glutathione (GSH) levels. This study lays a foundation for the further understanding of phenolamines in rape bee pollen.

Download Full-text

Derivatization of chlorin e6 with maleimide enhances its photodynamic efficacy in HepG2 cells

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424620500248 ◽

2020 ◽

Vol 24 (09) ◽

pp. 1093-1098

Author(s):

Xiuhan Guo ◽

Shisheng Wang ◽

Fan Zhang ◽

Guangzhe Li ◽

Yueqing Li ◽

...

Keyword(s):

Oxidative Stress ◽

Hepg2 Cells ◽

Redox System ◽

Chlorin E6 ◽

Ros Scavenging ◽

Cellular Redox ◽

New Strategy ◽

Maleimide Group ◽

High Level ◽

Derivatives Of

Three derivatives of chlorin e6 (1–3) were synthesized by introduction of maleimide, cysteine and glutathione at C-13 carboxyl of the chlorin scaffold. The evaluation of their PDT effects showed that compound 1, the derivative with a maleimide group, exhibited more potent photocytotoxicity against HepG2 cells (IC[Formula: see text] 3.2 [Formula: see text]M) than 2 (IC[Formula: see text] 6.7 [Formula: see text]M) and 3 (IC[Formula: see text] 10.2 [Formula: see text]M), although the cellular uptake of 1 was slightly lower than that of 2 and 3. The high PDT effect of 1 was found to be in agreement with the high level of intracellular singlet oxygen. Further investigation of the mechanism revealed that 1 can significantly lower the GSH level in HepG2 cells due to the addiction reaction of maleimide and GSH, thus resulting in the reduction of ROS scavenging and the enhancement of cellular oxidative stress. This approach to improve PDT effects of photosensitizers by means of interfering with the cellular redox system and enhancing cellular oxidative stress offers a new strategy for development of photosensitizers in cancer therapy.

Download Full-text

Physicochemical Properties and Effects of Honeys on Key Biomarkers of Oxidative Stress and Cholesterol Homeostasis in HepG2 Cells

Nutrients ◽

10.3390/nu13010151 ◽

2021 ◽

Vol 13 (1) ◽

pp. 151

Author(s):

Huong Thi Lan Nguyen ◽

Stefan Kasapis ◽

Nitin Mantri

Keyword(s):

Oxidative Stress ◽

Hepg2 Cells ◽

Antioxidant Activities ◽

Biochemical Properties ◽

Cholesterol Homeostasis ◽

Protective Effects ◽

Cholesterol Reduction ◽

Phenolic Contents ◽

Biomarkers Of Oxidative Stress ◽

Newtonian Behavior

Manuka honey and newly developed honeys (arjuna, guggul, jiaogulan and olive) were examined for their physicochemical, biochemical properties and effects on oxidative stress and cholesterol homeostasis in fatty acid-induced HepG2 cells. The honeys exhibited standard moisture content (<20%), electrical conductivity (<0.8 mS/cm), acidic pH, and monosaccharides (>60%), except olive honey (<60% total monosaccharides). They all expressed non-Newtonian behavior and 05 typical regions of the FTIR spectra as those of natural ones. Guggul and arjuna, manuka honeys showed the highest phenolic contents, correlating with their significant antioxidant activities. Arjuna, guggul and manuka honeys demonstrated the agreement of total cholesterol reduction and the transcriptional levels of AMPK, SREBP2, HCMGR, LDLR, LXRα. Jiaogulan honey showed the least antioxidant content and activity, but it was the most cytotoxic. Both jiaogulan and olive honeys modulated the tested gene in the pattern that should lead to a lower TC content, but this reduction did not occur after 24 h. All 2% concentrations of tested honeys elicited a clearer effect on NQO1 gene expression. In conclusion, the new honeys complied with international norms for natural honeys and we provide partial evidence for the protective effects of manuka, arjuna and guggul honeys amongst the tested ones on key biomarkers of oxidative stress and cholesterol homeostasis, pending further studies to better understand their modes of action.

Download Full-text

Characterization of the Protective Effect of Tetrahydrobiopterin Against S-Nitroso-N -Acetyl-D ,L-Penicillamine Induced Endothelial Cell Injury

Pteridines ◽

10.1515/pteridines.1999.10.1.14 ◽

1999 ◽

Vol 10 (1) ◽

pp. 14-19 ◽

Cited By ~ 4

Author(s):

Masakazu Ishii ◽

Shunichi Shimizu ◽

Kazutaka Momose ◽

Yuji Kiuchi ◽

Toshinori Yamamoto

Keyword(s):

Oxidative Stress ◽

Endothelial Cell ◽

Protective Effect ◽

Cell Injury ◽

Oxygen Species ◽

No Donor ◽

Endothelial Cell Injury ◽

Ros Scavenger ◽

Intracellular Oxidative Stress

The purpose of this study was to characterize the protective effect of tetrahydrobiopterin (BH4), one of the cofactors of nitric oxide (NO) synthase, against NO-induced endothelial cell injury. The addition of S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a NO donor, to endothelial cells induced the release of lactate dehydrogenase (LDH), a marker for cell injury. The SNAP-induced endothelial cell injury was markedly reduced by pretreatment with sepiapterin, a precursor of BH4 synthesis. On the other hand, exogenous BH4 had little effect on the SNAP-induced endothelial cell injury. We recently found that NO-induced endothelial cell injury involves a part of H202 production, since the injury was blocked by the treatment with catalase. Although BH4 released reactive oxygen species (ROS) in cell-free conditions, the increase in intracellular BH4 by pretreatment with sepiapterin strongly reduced H202-induced intracellular oxidative stress. These findings suggest that the increase in intracellular BH4 content but not extracellular BH4, strongly attenuates NO-induced endothelial cell injury by at least one of the mechanisms by which BH4 reduces H202-induced oxidative stress. Intracellular BH4 seems mainly to play a role as an antioxidant or as a ROS-scavenger.

Download Full-text

Activity Guided Isolation of Phenolic Compositions from Anneslea fragrans Wall. and Their Cytoprotective Effect against Hydrogen Peroxide Induced Oxidative Stress in HepG2 Cells

Molecules ◽

10.3390/molecules26123690 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3690

Author(s):

Shuyue He ◽

Xiaoyan Cui ◽

Afsar Khan ◽

Yaping Liu ◽

Yudan Wang ◽

...

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Hepg2 Cells ◽

Antioxidant Activities ◽

Folk Medicine ◽

Ethanol Extract ◽

Total Phenolic ◽

Protective Effects ◽

Significant Difference ◽

Nonpolar Organic

Anneslea fragrans Wall., commonly known as “Pangpo Tea”, is traditionally used as a folk medicine and healthy tea for the treatment of liver and intestine diseases. The aim of this study was to purify the antioxidative and cytoprotective polyphenols from A. fragrans leaves. After fractionation with polar and nonpolar organic solvents, the fractions of aqueous ethanol extract were evaluated for their total phenolic (TPC) and flavonoid contents (TFC) and antioxidant activities (DPPH, ABTS, and FRAP assays). The n-butanol fraction (BF) showed the highest TPC and TFC with the strongest antioxidant activity. The bio-guided chromatography of BF led to the purification of six flavonoids (1–6) and one benzoquinolethanoid (7). The structures of these compounds were determined by NMR and MS techniques. Compound 6 had the strongest antioxidant capacity, which was followed by 5 and 2. The protective effect of the isolated compounds on hydrogen peroxide (H2O2)-induced oxidative stress in HepG2 cells revealed that the compounds 5 and 6 exhibited better protective effects by inhibiting ROS productions, having no significant difference with vitamin C (p > 0.05), whereas 6 showed the best anti-apoptosis activity. The results suggest that A. fragrans could serve as a valuable antioxidant phytochemical source for developing functional food and health nutraceutical products.

Download Full-text