Characterization, evaluation of nutritional parameters of Radix isatidis protein and its antioxidant activity in D-galactose induced ageing mice

Abstract

BackgroundRadix isatidis (Isatis indigotica Fort.) is an ancient medicinal herb, which has been applied to the prevention and treatment of influenza virus since ancient times. In recent years, the antioxidant activity of Radix isatidis has been widely concerned by researchers. Our previous studies have shown that Radix isatidis protein (RIP) has good antioxidant activity in vitro. In this study, the composition of the protein was characterized and its antioxidant activity in vivo was evaluated.MethodsThe model of oxidative damage in mice was established by subcutaneous injection of D-galactose for 7 weeks. Commercially available kits were used to determine the content of protein and several oxidation indexes in different tissues of mice. The tissue samples were stained with hematoxylin and eosin (H&E) and the pathological changes were observed by optical microscope. The molecular weight of RIP was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The amino acid composition of RIP was determined by a non-derivative method developed by our research group.ResultsRIP significantly increased the activities of antioxidant enzymes such as SOD, CAT, GSH-Px and total antioxidant capability (TAOC) but decreased the MDA level in the serum, kidney and liver. H&E stained sections of liver and kidney revealed D-galactose could cause serious injury and RIP could substantially attenuate the injury. The analysis of SDS-PAGE showed that four bands with molecular weights of 19.2 kDa, 21.5 kDa, 24.8 kDa and 40.0 kDa were the main protein components of RIP.ConclusionsThe results suggested that RIP had excellent antioxidant activity, which could be explored as a health-care product to retard aging and a good source of protein nutrition for human consumption.

Mixture of Five Fermented Herbs (Zhihuasi Tk) Alters the Intestinal Microbiota and Promotes the Growth Performance in Piglets

“…As the other ingredient in the mixture of Z. Tk , Radix isatidis is well-known for its broad antiviral activities and antioxidant properties. For example, it was reported that the proteins in R isatidis could eliminate the damage of free radicals, showing a strong antioxidant effect in vivo ( Xiao et al, 2019 ). Furthermore, ingredients, such as white peony polyphenols, isolated from R. paeoniae alba ( Zhou et al, 2019 ) and atractylenolides isolated from Atractylodes macrocephalae ( Bailly, 2020 ) are also effective antioxidants.…”

Protective effects of ginseng stem-leaf saponins on D-galactose-induced reproductive injury in male mice

“…When the D-gal concentration exceeds normal level, it is converted to aldehydes and H 2 O 2 [ 32 , 33 ]. Animals injected with D-gal showed aging-related phenotypes, such as decreased immune responses, neurological defects, decreased antioxidant enzyme activity, increased ROS production and reproductive aging [ 14 , 34 – 36 ]. Ahangarpour et al used 500mg/kg D-galactose for six weeks and reported decreased sperm counts and increased serum LH levels in male mouse [ 31 ].…”

Is galactose a hormetic sugar? Evidence from rat hippocampal redox regulatory network

“…The third important mechanism suggests galactose generates H2O2 by undergoing an oxidation reaction catalyzed by galactose oxidase (GO; EC 1.1.3.9) 17,18 and some researchers suggest that this is, in fact, the only metabolic route of galactose that produces reactive oxygen species (ROS) 21 . Interestingly, although a substantial number of researchers working with galactose-induced models of aging in rodents refer to GO-mediated generation of H2O2 as an important mechanism explaining the detrimental effects of galactose 17,18,[22][23][24][25][26][27][28][29][30][31][32][33][34] , this is a fungal enzyme that doesn't exist in rodents which makes these strong claims slightly suspicious as addressed in our recent comment 35 .…”