scholarly journals Reviews on Mechanisms ofIn VitroAntioxidant Activity of Polysaccharides

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Junqiao Wang ◽  
Shuzhen Hu ◽  
Shaoping Nie ◽  
Qiang Yu ◽  
Mingyong Xie

It is widely acknowledged that the excessive reactive oxygen species (ROS) or reactive nitrogen species (RNS) induced oxidative stress will cause significant damage to cell structure and biomolecular function, directly or indirectly leading to a number of diseases. The overproduction of ROS/RNS will be balanced by nonenzymatic antioxidants and antioxidant enzymes. Polysaccharide or glycoconjugates derived from natural products are of considerable interest from the viewpoint of potentin vivoandin vitroantioxidant activities recently. Particularly, with regard to thein vitroantioxidant systems, polysaccharides are considered as effective free radical scavenger, reducing agent, and ferrous chelator in most of the reports. However, the underlying mechanisms of these antioxidant actions have not been illustrated systematically and sometimes controversial results appeared among various literatures. To address this issue, we summarized the latest discoveries and advancements in the study of antioxidative polysaccharides and gave a detailed description of the possible mechanisms.

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3740
Author(s):  
Muddaser Shah ◽  
Waheed Murad ◽  
Najeeb Ur Rehman ◽  
Sobia Ahsan Halim ◽  
Manzoor Ahmed ◽  
...  

In the current study, in vitro antimicrobial and antioxidant activities and in vivo anti-inflammatory and analgesic activities of Scutellaria edelbergii Rech. f. (crude extract and subfractions, i.e., n-hexane, ethyl acetate (EtOAc), chloroform, n-butanol (n-BuOH) and aqueous) were explored. Initially, extraction and fractionation of the selected medicinal plant were carried out, followed by phytochemical qualitative tests, which were mostly positive for all the extracts. EtOAc fraction possessed a significant amount of phenolic (79.2 ± 0.30 mg GAE/g) and flavonoid (84.0 ± 0.39 mg QE/g) content. The EtOAc fraction of S. edelbergii exhibited appreciable antibacterial activity against Gram-negative (Escherichia coli and Klebsiella pneumoniae) strains and significant zones of inhibition were observed against Gram-positive bacterial strains (Bacillus subtilis and Staphylococcus aureus). However, it was found inactive against Candida Albicans and Fusarium oxysporum fungal strains. The chloroform fraction was the most effective with an IC50 value of 172 and 74 µg/mL against DPPH (1,1-Diphenyl-2-picryl-hydrazyl) and ABTS assays, in comparison with standard ascorbic acid 59 and 63 µg/mL, respectively. Moreover, the EtOAc fraction displayed significant in vivo anti-inflammatory activity (54%) using carrageenan-induced assay and significant (55%) in vivo analgesic activity using acetic acid-induced writing assay. In addition, nine known compounds, ursolic acid (UA), ovaul (OV), oleanolic acid (OA), β-sitosterol (BS), micromeric acid (MA), taraxasterol acetate (TA), 5,3′,4′-trihydroxy-7-methoxy flavone (FL-1), 5,7,4′-trihydroxy-6,3′-dimiethoxyflavone (FL-2) and 7-methoxy catechin (FL-3), were isolated from methanolic extract of S. edelbergii. These constituents have never been obtained from this source. The structures of all the isolated constituents were elucidated by spectroscopic means. In conclusion, the EtOAc fraction and all other fractions of S. edelbergii, in general, displayed a significant role as antibacterial, free radical scavenger, anti-inflammatory and analgesic agents which may be due to the presence of these constituents and other flavonoids.


Nutrients ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 3968
Author(s):  
Paula Aranaz ◽  
Adriana Peña ◽  
Ariane Vettorazzi ◽  
María José Fabra ◽  
Antonio Martínez-Abad ◽  
...  

In recent years, food ingredients rich in bioactive compounds have emerged as candidates to prevent excess adiposity and other metabolic complications characteristic of obesity, such as low-grade inflammation and oxidative status. Among them, fungi have gained popularity for their high polysaccharide content and other bioactive components with beneficial activities. Here, we use the C. elegans model to investigate the potential activities of a Grifola frondosa extract (GE), together with the underlying mechanisms of action. Our study revealed that GE represents an important source of polysaccharides and phenolic compounds with in vitro antioxidant activity. Treatment with our GE extract, which was found to be nongenotoxic through a SOS/umu test, significantly reduced the fat content of C. elegans, decreased the production of intracellular ROS and aging–lipofuscin pigment, and increased the lifespan of nematodes. Gene expression and mutant analyses demonstrated that the in vivo anti-obesity and antioxidant activities of GE were mediated through the daf-2/daf-16 and skn-1/nrf-2 signalling pathways, respectively. Taken together, our results suggest that our GE extract could be considered a potential functional ingredient for the prevention of obesity-related disturbances.


2020 ◽  
Vol 16 (7) ◽  
pp. 1144-1159
Author(s):  
Sang-Eun Hong ◽  
Jong Hun An ◽  
Seong-Lan Yu ◽  
Jaeku Kang ◽  
Chang Gyo Park ◽  
...  

Oxidative stress is one of the principal causes of hypoxia-induced kidney injury. The ceria nanoparticle (CNP) is known to exhibit free radical scavenger and catalytic activities. When zirconia is attached to CNPs (CZNPs), the ceria atom tends to remain in a Ce3+ form and its efficacy as a free radical scavenger thus increases. We determined the effectiveness of CNP and CZNP antioxidant activities against hypoxia-induced acute kidney injury (AKI) and observed that these nanoparticles suppress the apoptosis of hypoxic HK-2 cells by restoring autophagy flux and alleviating mitochondrial damage. In vivo experiments revealed that CZNPs effectively attenuate hypoxia-induced AKI by preserving renal structures and glomerulus function. These nanoparticles can successfully diffuse into HK-2 cells and effectively counteract reactive oxygen species (ROS) to block hypoxia-induced AKI. This suggests that these particles represent a novel approach to controlling this condition.


2003 ◽  
Vol 305 (3) ◽  
pp. 1183-1190 ◽  
Author(s):  
Minoru Satoh ◽  
Naoki Kashihara ◽  
Sohachi Fujimoto ◽  
Hideyuki Horike ◽  
Takehiko Tokura ◽  
...  

2000 ◽  
Vol 352 (2) ◽  
pp. 381-387 ◽  
Author(s):  
Jonas NILSSON ◽  
Amel GRITLI-LINDE ◽  
Olle HEBY

Hemizygous gyro male (Gy/Y) mice are a model for X-linked hypophosphataemic rickets. As in humans, the disease is caused by deletions in the Phex gene, a phosphate-regulating gene having homologies with endopeptidases on the X chromosome. Some phenotypic abnormalities in Gy/Y mice have recently been attributed to the fact that the Gy deletion also includes the neighbouring spermine synthase gene, resulting in spermine deficiency. Spermine and its precursors spermidine and putrescine are essential for cell growth and differentiation. As a novel method for studying the function of spermine, we established primary cultures of skin fibroblasts from hemizygous Gy/Y mice. The Gy/Y cells contained no detectable spermine. In view of the fact that spermine is a free-radical scavenger in vitro, we were surprised to find that Gy/Y cells were more resistant to oxidative stress than their normal (X/Y) counterparts. However, our finding that spermidine accumulates markedly in the spermine-deficient Gy/Y cells can probably explain this increased resistance. It is the first indication that spermidine can serve as a free-radical scavenger in vivo and not only in vitro. When subjecting the Gy/Y cells to UV-C irradiation we made another interesting finding: the mutant cells were more sensitive than the normal X/Y cells. This finding indicates that spermine, probably because of its high-affinity binding to DNA, is important in protection against chromatin damage.


2002 ◽  
Vol 20 (10) ◽  
pp. 2575-2601 ◽  
Author(s):  
Vijayalaxmi ◽  
Charles R. Thomas ◽  
Russel J. Reiter ◽  
Terence S. Herman

ABSTRACT: Melatonin, the chief secretory product of the pineal gland, is a direct free radical scavenger, an indirect antioxidant, as well as an important immunomodulatory agent. In both in vitro and in vivo investigations, melatonin protected healthy cells from radiation-induced and chemotherapeutic drug–induced toxicity. Furthermore, several clinical studies have demonstrated the potential of melatonin, either alone or in combination with traditional therapy, to yield a favorable efficacy to toxicity ratio in the treatment of human cancers. This study reviews the literature from laboratory investigations that document the antioxidant and oncostatic actions of melatonin and summarizes the evidence regarding the potential use of melatonin in cancer treatment. This study also provides rationale for the design of larger translational research–based clinical trials.


2020 ◽  
Vol 17 (10) ◽  
pp. 845-860 ◽  
Author(s):  
Sabya S. Das ◽  
Afzal Hussain ◽  
Priya R. Prasad Verma ◽  
Syed S. Imam ◽  
Mohammad A. Altamimi ◽  
...  

Quercetin (QT, 3,3′,4′,5,7-pentahydroxyflavone), is a natural flavonoid with nutritional value and acts as a potential free-radical scavenger (antioxidant). QT has also been explored for its anti-cancer as well as anti-proliferative activities against numerous cancerous cells. Moreover, QT exhibits significant pro-apoptotic activity against tumor cells and is well established to control the growth of different carcinoma cells at various phases of the cell cycle. Hence, it can reduce the burden of human solid cancer and metastasis. Both these activities have been established in a diverse class of human cell lines in-vitro as well as in animal models (in-vivo). Apart from the promising therapeutic activities of QT molecule, their applications have been limited due to some major concerns, including low oral bioavailability and poor aqueous solubility. Also, rapid gastrointestinal digestion of QT seems to be a key barrier for its clinical translations for oral drug delivery in conventional dosage form. Henceforth, to overcome these drawbacks, QT is loaded with liposomal systems, which exhibit promising outcomes in the upregulation of QT by the epithelial system and also improved its targeting at the site of action. Furthermore, Liposomes based Drug Delivery Systems (LDDS) have showed significant therapeutic activity with conjugated drug moiety and exhibit safety, biocompatibility, biodegradability, and mitigated toxicity despite having certain limitations associated with physiological and biological barriers. Herein, in this review, we have focused on the mechanism related with the chemotherapeutic activity of QT and also discussed the promising activity of QT-loaded LDDS as a potent chemotherapeutic agent for cancer therapy.


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