Mechanisms of Nrf2/HO-1 pathway up-regulation induced by pu-erh black tea extract supplementation for quinocetone-treated Sprague-Dawley rats

Possible Mechanisms of Dark Tea in Cancer Prevention and Management: A Comprehensive Review

“…At the concentration range of 1.25 to 6.25 mg/mL, Pu'er tea has obvious intracellular ROS clearance ability on human cancer cells (Caco2, HEp2, Hep G2 cell lines), and theabrownins are the main contributor [74] ROS determination 2S,3R-6-methoxycarbonylgallocatechin (MCGE) MCGE protects cells from the production of ROS in UVB-exposed keratinocytes (HACats) by activating the Nrf2 pathway [75] Cell viability 8-C N-ethyl-2-pyrrolidinone substituted flavan-3-ols The 8-C N-ethyl-2-pyrrolidinone substituted flavan-3-ols possessed significant antioxidant activity and could prevent HMEC damage caused by H 2 O 2 [76] Mice exposed to 7.0 and 7.5 Gy total body irradiation Dark tea extract Dark tea extract reduced ROS levels in hematopoietic cells by inhibiting the expression of NOX4 [77] Obese rat model Pu'er tea Pu'er tea increased the activity of antioxidant enzymes such as SOD and GSH-Px, while decreased the level of lipid peroxidation product MDA in obese rats [78,79] t-BHP oxidative stress-induced rat hepatocyte model Pu'er tea Pu'er tea extract decreased the production of ROS marker O 2 − in rat hepatocytes and prevented t-BHP induced mitochondrial oxidative stress [80] SD rats Balb/c mice Pu'er tea Pu'er tea reduced quinocetone-induced oxidative stress [81,82] Wistar rats Pu'er tea Pu'er tea decreased MDA and GSH, and increased SOD and GSH-Px levels [83] Mice with acute alcoholic liver injury…”

“…Pu’er tea extract reduces serum MDA levels induced by quinocetone and increases the activities of GSH, SOD, and GPx. The main mechanism is to improve ERK phosphorylation levels and thus increase Nrf2/HO-1 pathway expression [ 81 ]. Similar results have also been confirmed.…”

The effect of theabrownins on the amino acid composition and antioxidant properties of hen eggs

“…Theaflavin and thearubigins have been reported to have better scavenging ability to superoxide and nitrogen species as compared to green tea polyphenols ( Sarkar and Bhaduri, 2001 ; Liu et al, 2021b ). Theabrownins exhibit several diverse health benefits, including hypolipidemic properties, antiobesity, anti-inflammatory, antioxidative, antitumor, free radical scavenging, and toxicity suppressing activities ( Yu et al, 2015 ; Huang et al, 2019a ; Liu et al, 2021a ). It has been reported that the addition of green tea polyphenols (400–600 mg/kg) and epicatechin (166–400 mg/kg epigallocatechin-3-gallate [ EGCG ]) were able to improve egg laying rate, feed efficiency, and egg albumen quality ( Ariana et al, 2011 ; Wang et al, 2017 ).…”

“…Transcriptional factor Nrf2 is an important redox-sensitive regulator which increases cellular defense mechanisms against xenobitic and oxidative stress through the antioxidant and detoxification genes, as we as enzymes involved in phase I and II detoxification process ( Jaramillo and Zhang, 2013 ; Tonelli et al, 2018 ). Black tea polyphenols were also shown to enhance the expression of antioxidant enzymes (NOQ1 and GST) by up-regulating Nrf2-ARE pathway in model animals ( Patel and Maru, 2008 ; Yu et al, 2015 ; Li et al, 2020 ). However, whether the Nrf2 signaling pathway is involved in the albumen improving effect of TBs in poultry model is still not known.…”

Soyasaponin bb protects rat hepatocytes from alcohol-induced oxidative stress by inducing heme oxygenase-1

“…[17] Increasing evidence supported that many natural products extracted from food could induce the expression of HO-1, and represent enhanced resistance to various oxidative stresses. [18192021] These functional extracts have shown good potential on relieving alcohol-induced oxidative stress.…”