Acute Toxicity, Antioxidant, and Antifatigue Activities of Protein‐Rich Extract from Oviductus ranae

Abstract

The paper investigated the preparation, amino acid composition, acute toxicity, and in vitro and in vivo antioxidant, coupled with in vivo antifatigue activities of protein-rich extract of Oviductus ranae (PEOR). The results indicated that PEOR possesses high-safety property with maximum tolerated dose (MTD) higher than 20 g/kg in mice, shows weak scavenging capacities against hydroxyl, superoxide anion, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, as well as ferric-reducing antioxidant power in vitro, but exerts strong antioxidant effect in ethanol-induced oxidative stress mice model; it can decrease malonaldehyde (MDA) and protein carbonyl (PCO) formation and increase total superoxide dismutase (T-SOD) activity and glutathione (GSH) synthesis. Besides the strong in vivo antioxidant activity, PEOR in a dose of 400 mg/kg also has antifatigue effect in mice, and it can prolong the exhaustive swimming time, reduce the elevated blood urea nitrogen (BUN) and blood lactic acid (BLA) caused by intense exercise. The in vivo activity of PEOR may be contributed by its absorbed amino acids, due to the fact that eight antioxidant amino acids and twelve glucogenic ones were found in it. This study will provide an evidence for the clinical use of PEOR as a dietary supplement for antioxidant and antifatigue in the same oral dose (400 mg/kg).

Traditional Uses, Bioactive Constituents, Biological Functions, and Safety Properties of Oviductus ranae as Functional Foods in China

“…It is worthwhile to note that bioactive studies and clinical practices provide strong evidence for the functions of OR on immunomodulation, antioxidation, and antifatigue. In previous work, we also observed that protein-rich extracts from OR elicit significant antioxidant and antifatigue activities [84].…”

“…In a previous work [84], we investigated the preparation, amino acid composition, and in vitro and in vivo antioxidant activities of WPOR and found that WPOR exert weaker in vitro radical-scavenging capacities to hydroxyl, superoxide anion, and DPPH as well as ferric-reducing power compared with vitamin C (VC) but show stronger antioxidant effects in an ethanol-induced oxidative stress mouse model. These results were in accordance with the general findings that proteins and polypeptides usually exhibit lower in vitro free radical-scavenging capacities than their smaller peptides and amino acids, due to the fact that substances with smaller molecular weight may be prone to interact with free radicals more effectively [131].…”

“…Then, the protein-rich extract from OR (PEOR) was prepared and analyzed; before bioactive evaluations, the acute toxicity of PEOR was conducted in doses of 5, 10, and 20 g/kg BW to preliminarily assess its edible safety. Results demonstrated that the maximal tolerated dose (MTD) of PEOR in mice was higher than 20 g/kg BW and oral administration of PEOR in a single dose of 20 g/kg BW had no effects on body weight, relative organ weight, biochemical parameters, and histopathological changes [84]. In the near future, the toxicity evaluations regarding multiple doses of PEOR will be performed to further verify its safety profiles.…”

A Polysaccharide-Rich Fraction Derived from Oviductus ranae with Antioxidant and Immunomodulatory Potentials

“…VC was used as positive control. The hydroxyl radical-scavenging rate was calculated according to the following equation (Zhang et al, 2018):…”

“…Recent studies have found that OR shows immune enhancement, anti-fatigue, antiosteoporosis, anti-oxidation, anti-apoptosis, reproductive protection and estrogen-like effects. The proteins and steroids of OR have been well studied (Wang et al, 2010;Zhang et al, 2018). However, little information is available on the Polysaccharides from OR (POR).…”