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To optimize the extraction of polysaccharides from Notopterygium franchetii Boiss (NFP), microwave-assisted aqueous two phase system (MAATPS) and response surface methodology (RSM) were employed. Results showed that the optimum conditions of MAATPS were as follows: ethanol concentration of 32 % (w/w), (NH 4 ) 2 SO 4 concentration of 24 % (w/w) and extraction time of 15 min. Under such condition, Y S (the recovery of polysaccharides) was 80.57 % with 90.40 % of Y P (the recovery of proteins). In addition, analysis of the physicochemical properties of extracted polysaccharides (NFP-MAATPS) under the optimal conditions indicated that compared to polysaccharides extracted by traditional extraction method (NFP-HWE), NFP-MAATPS exhibited higher extraction efficiency, decreased average molecular weight, different monosaccharide compositions and mole ratios. Moreover, NFP-MAATPS exhibited stronger antioxidant activity in vitro and more potent anti-inflammatory activity in zebrafish embryos than NFP-HWE. Our results suggest that purified NFP-MAATPS could be potentially used in complementary medicines or functional foods., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Recently it was discovered that thioproline, an unnatural analog of proline, can arise in vivo from the reaction of cysteine and formaldehyde in cells under oxidative stress. Sequence-specific bioincorporation of thioproline into proteins was studied via shotgun proteomics of Escherichia coli (E. coli) cells. In a strain auxotrophic for proline, thioproline was found widely incorporated in lieu of proline when the cells were incubated with thioproline. In total 1428 proteins and 235 distinct thioproline-containing peptides were identified. Label-free relative quantitation revealed 102 differentially expressed proteins (82 up-regulated and 20 down-regulated) in the thioproline-treated group (with thioproline in the medium) relative to the control group (with proline in the culture medium). Pathway enrichment analysis of the differentially expressed proteins showed that amino acid biosynthesis and protein synthesis has been most affected by thioproline exposure, as expected. Phenotypically, the thioproline-treated group was found to exhibit slower cell growth and stronger antioxidant capacity relative to the control. SIGNIFICANCE: Thioproline is a secondary metabolite of formaldehyde and a structural analog of proline. It is also known to exhibit a wide variety of pharmaceutical properties, but its exact biochemical role in the cell has not been elucidated. In this paper, we studied thioproline misincorporation (in lieu of proline) events during protein synthesis in E. coli. Global proteome profiling revealed that thioproline is extensively misincorporated throughout the proteome in E. coli cells exposed to thioproline, and pathways related to amino acid and protein biosynthesis are up-regulated. In addition, we demonstrated that pretreatment with thioproline appeared to increase E. coli cells' capacity to tolerate oxidative stress. Our findings suggest a novel explanation of thioproline's known antioxidative properties. This is, to our knowledge, the first ever study of thioproline misincorporation at the proteome level in any organism., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The purpose of this research was to evaluate the therapeutic effects of gentiopicroside (GPS) on adjuvant-induced arthritis (AA) rats. Rats were injected with complete Freund's adjuvant (CFA) for 0.1 mL in the right hind paw to induce AA. Thirty rats from three groups were treated with GPS (30, 60, 90 mg/kg) from day 15 to day 26. Arthritis was evaluated by arthritis index, paw volume, paw thickness, and X-ray. The effect of GPS on inflammation was assessed by measuring the levels of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6 and IL-17, as well as related mRNA. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glutathione (GSH) protein carbonyl (PCO) and malondialdehyde (MDA) were measured to assess the effect of GPS on oxidative stress. These results indicate that GPS increases the levels of GSH-Px, SOD and GSH, and reduces the levels of MDA and PCO. GPS can significantly down-regulate the levels of IL-1β, TNF-α, IL-6 and IL-17, as well as related mRNA. In addition, X-ray and histopathological results show that GPS has a therapeutic effect on joints in AA rats. In summary, the therapeutic effects of GPS on AA rats are associated with anti-inflammation and antioxidation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Recently, the flowers of Dendrobium catenatum (D. officinale) have been approved as new food ingredient. This study aimed to investigate the herb-markers and their antioxidant activities in methanolic extracts of D. catenatum flowers, and to establish the quality evaluation methods for raw materials and their products of flower by HPLC. The methanolic extract of 11 strains of D. catenatum flowers were found to contain a high content of total phenol and flavonoids, and they possessed potential antioxidant capacities based on DPPH radical scavenging assay. A total of 21 phenolic herb-markers were selected according to the similarity and principal component analysis of the chromatographic fingerprinting profiles. Their structures were further elucidated by UV, HPLC-DAD-ESI-QTOF-MS/MS and NMR analyses. The identified compounds included 2 phenylpropanoids, 11C-glycosylflavones and 6 O-glycosylflavones, which could be employed as the indicators for quantitative evaluation of the quality and authenticity of the flowers. Based on the pre-column DPPH/ABTS + -HPLC analysis, the major compounds contributed to the antioxidative activity were identified as 1-O-caffeoyl-β-D-glucoside, rutin and isoquercitrin, all of which, were also the most abundant constituents in the methanolic extract. The results suggest the potential of D. catenatum flowers as a new antioxidant resources for medicinal and food products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Human spermatozoa cryopreservation is an important means of assisted reproductive technology and male fertility preservation. Although this technique is particularly useful, sperm cryopreservation significantly reduces the quality of spermatozoa after freezing and thawing. The objective of the study is to examine the efficacy of mitochondria-targeted antioxidant MitoTEMPO in improving sperm quality during semen cryopreservation processes. Semen samples were collected and cryopreserved in extenders containing different concentrations (0.0, 0.5, 5, 50, and 500 μM) of MitoTEMPO. Sperm motility, viability, membrane integrity, mitochondrial membrane potential and antioxidant activities were measured and analyzed. The results showed that the addition of MitoTEMPO (5-50 μM) significantly improved post-thaw sperm motility, viability, membrane integrity and mitochondrial membrane potential (P < .05). Meanwhile, antioxidant enzymes activities were enhanced and MDA content were decreased in the group supplemented with MitoTEMPO. In conclusion, mitochondria-targeted antioxidant MitoTEMPO improves the post-thaw sperm quality and antioxidant enzymes profile., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Omeprazole is a mainstay of therapy for gastroesophageal reflux disease (GERD) and gastritis, and is increasingly used as an over-the-counter remedy for dyspepsia. Omeprazole acts by selectively oxidizing thiol targets in the gastric proton pump, but it also appears to be toxic to the gastric mucosa. We hypothesized that omeprazole toxicity is due to non-specific oxidation of cell structures other than the proton pump, and tested the efficacy of antioxidants to prevent omeprazole-induced toxicity in isolated rabbit gastric glands. Toxicity was measured by uptake and converstion of calcein-AM, following three hours of exposure to omeprazole and a non-selective thiol-oxidant, monochloramine. Intracellular concentration of Zn(2+) and the capacity to maintain luminal acidity were monitored using the fluorescent reporters fluozin-3 and Lysosensor DND-160, respectively. Both omeprazole and monochloramine caused marked reduction in cell viability. The toxicity of omeprazole was independent of monochloramine toxicity. The thiol reducing agent dithiothreitol protected gastric glands from injury. The oxidant scavenger Vitamin C also protected, and did not impair the anti-secretory effects of omeprazole. Thus, omeprazole toxicity appears to be oxidative and preventable with antioxidant therapy, including Vitamin C. Vitamin C may be a safe and efficacious addition to treatments requiring the use of PPIs., (Copyright 2010 Elsevier Inc. All rights reserved.)

Acute liver injury is a common consequence of taking overdose of acetaminophen (APAP). The aim of this study was to evaluate the antioxidant activity and hepatoprotective effect of a mangrove plant Sonneratia apetala fruit extract (SAFE) on APAP-induced liver injury in mice. Mice were orally pretreated with SAFE (100, 200, and 400 mg/kg) daily for one week. The control and APAP groups were intragastrically administered with distilled water, and NAC group was treated with N-Acetyl-L-cysteine (NAC) before APAP exposure. The results manifested that SAFE significantly improved survival rates, attenuated hepatic histological damage, and decreased the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in serum in APAP-exposed mice. SAFE treatment also increased glutathione (GSH) level and glutathione peroxidase (GSH-Px) activity, enhanced catalase (CAT), and total antioxidant capacity (T-AOC), as well as reducing malondialdehyde (MDA) level in liver. In addition, the formation of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and elevation of myeloperoxidase (MPO) in APAP-exposed mice were inhibited after SAFE treatment. And SAFE also displayed high DPPH radical scavenging activity and reducing power in vitro. The main bioactive components of SAFE such as total phenol, flavonoid, condensed tannin, and carbohydrate were determined. The current study proved that SAFE exerted potential protective effect against APAP-induced acute liver injury, which might be associated with the antioxidant and anti-inflammatory activities of SAFE. [ABSTRACT FROM AUTHOR]

Vitiligo is a common depigmentary disease characterized as diagnosis simplicity and cure difficulty in view of the ambiguity of etiology, thus novel and effective treatments are urgently needed. Paeoniflorin, the major active compound extracted from the root of Paeonia lactiflora Pall , a traditional Chinese medicine, has been validated pharmacological properties such as antioxidant stress, a theory participating in the occurrence of vitiligo, but the effect on melanogenesis is still unclear. In this study, melanosythesis effect of paeoniflorin and the potential mechanism were evaluated. We found that treatment with paeoniflorin at the concentration of 10 μg/ml significantly increased melanin content and intracellular tyrosinase activity of human melanocytes, in accordance with the elevation of protein levels of microphthalmia-associated transcription factor (MITF), tyrosinase-related protein 1 (TRP-1). In addition, we also investigated that paeoniflorin promoted phosphorylation of cAMP-response element binding (CREB) and extracellular signal-regulated kinase (ERK) without affecting p38 and c-Jun N-terminal kinase (JNK). These results demonstrated that paeoniflorin had a synergistic effect on normal human melanocytes via ERK/CREB pathway with up-regulation of MITF and TRP-1, enhancing melanin synthesis. Meanwhile, the milder pathological changes in vitiligo mice treat with paeoniflorin also confirmed its potential in treating vitiligo. To sum up, we suggest that paeoniflorin may be a potential medicine of vitiligo treatment in clinical. Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • We developed a HPLC based fingerprint method to simultaneously detect multi-target ingredients in Dendranthema lavandulifolium buds (Jumi). • We identified 6 phenylpropanoids, 5 flavonoids, and 2 volatile components in Jumi. • Phenylpropanoids and flavonoids are the main antioxidants in Jumi. • Eriodictyol-7- O-β - d -glucuronpyranoside, 3,5-diCQA, 3-CQA, and 4,5-diCQA are the main markers to distinguish Jumi from other buds. Abstract The bud of Dendranthema lavandulifolium (Jumi) is a featured agricultural product in Zhejiang Province (China) with active effects on liver detoxing and vision improvement. In order to evaluate the quality and identify geographical origin of Jumi, a high performance liquid chromatography (HPLC) chemical fingerprinting method was developed for simultaneous detection of multi-target components. Among the 16 common peaks in the fingerprint, 6 phenylpropanoids, 5 flavonoids and 2 volatile compounds were identified through combinational analytical applications of ultraviolet spectrum (UV), nuclear magnetic resonance spectroscopy (NMR), liquid chromatography–mass spectrometry (LC–MS) and gas chromatography–mass spectrometry (GC–MS). Phenylpropanoids and flavonoids were found to be the major potential antioxidants in Jumi based on the pre-column DPPH-HPLC assay. For simultaneous analysis of multi-target components, HPLC quantitative method was constructed by using 11 identified compounds. The results demonstrated that the chemical compositions and contents among 10 batches of Jumi are consistent. 6 phenylpropanoids and 3 flavonoids appeared as the main constituents in Jumi and showed obviously higher contents (>1 mg/g). Especially, the contents of two flavanones, eriodictyol-7- O-β - d -glucuronide and eriodictyol-7- O-β - d -glucoside are prominent in Jumi. The principal component analysis (PCA) suggests obvious differences between Jumi and other cultivars buds. Eriodictyol-7- O-β - d -glucuronide, isochlorogenic acid A (3, 5-diCQA), chlorogenic acid (3-CQA), and isochlorogenic acid C (4, 5-diCQA) can be used as the specific target components to distinguish Jumi from other buds. [ABSTRACT FROM AUTHOR]

Chimonanthus Lindl. has seven family members with Ch. praecox blooming in winter and others in autumn. The plants are widely used in landscaping, fragrance industry, as well as production of medicinal material because of their flower fragrance. Both Chimonanthus flowers and leaves contain abundant secondary metabolites. But it is unclear whether the flowers from different species have distinct ingredients and antioxidant activity. To address the question, we evaluated the main compositions of the flowers from five Chimonanthus species and analyzed the antioxidant activity of the compositions. The results indicated that flavonoids and coumarins are the two major types of substances with antioxidant capacity in Chimonanthus flowers. Totally nine antioxidative compounds, including scopolin and scopoletin, were identified based on the high performance liquid chromatography-photo diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD/ESI–MS). All the antioxidant compounds were confirmed by pre-column 2, 2-diphenyl-1- picryhydrazyl (DPPH) assay. Rutin (highest in content), isoquercitrin and quercetin appeared stronger scavenging DPPH radical ability than the other five compounds, mainly due to their ortho -dihydroxyl groups. Among the five Chimonanthus species, Ch . praecox flower is most abundant in secondary metabolites and shows most potent antioxidant activity. The other four flowers contain the same types of ingredients with Ch. praecox , but exhibit lower antioxidant activity. The results obtained from this comprehensive analysis provide a theoretical basis for the utilization of the plant resources of Chimonanthus genus. [ABSTRACT FROM AUTHOR]

Significance: Cytochrome c oxidase (COX), the last enzyme of the mitochondrial respiratory chain, is the major oxygen consumer enzyme in the cell. COX biogenesis involves several redox-regulated steps. The process is highly regulated to prevent the formation of pro-oxidant intermediates. Recent Advances: Regulation of COX assembly involves several reactive oxygen species and redox-regulated steps. These include: (i) Intricate redox-controlled machineries coordinate the expression of COX isoenzymes depending on the environmental oxygen concentration. (ii) COX is a heme A-copper metalloenzyme. COX copper metallation involves the copper chaperone Cox17 and several other recently described cysteine-rich proteins, which are oxidatively folded in the mitochondrial intermembrane space. Copper transfer to COX subunits 1 and 2 requires concomitant transfer of redox power. (iii) To avoid the accumulation of reactive assembly intermediates, COX is regulated at the translational level to minimize synthesis of the heme A-containing Cox1 subunit when assembly is impaired. Critical Issues: An increasing number of regulatory pathways converge to facilitate efficient COX assembly, thus preventing oxidative stress. Future Directions: Here we will review on the redox-regulated COX biogenesis steps and will discuss their physiological relevance. Forthcoming insights into the precise regulation of mitochondrial COX biogenesis in normal and stress conditions will likely open future perspectives for understanding mitochondrial redox regulation and prevention of oxidative stress. Antioxid. Redox Signal. 19, 1940-1952. [ABSTRACT FROM AUTHOR]