Persimmon vinegar polyphenols protect against hydrogen peroxide-induced cellular oxidative stress via Nrf2 signalling pathway

Folic Acid Alleviates Hydrogen Peroxide-Induced Oxidative Stress in Bovine Placental Trophoblast Cells by Regulating the NRF2/mTOR Signaling Pathway

As one of the important components of placental structure, the integrity of placental trophoblast cells is crucial for placental function. When oxidative stress continues to act on placental trophoblast cells, it can cause changes in placental structure and function. Research has shown that folic acid (FA) has a certain alleviating effect on the functional damage of trophoblast cells caused by oxidative stress, but the mechanism of action is still unclear. Therefore, this study focuses on bovine placental trophoblast cells (BPTCs) to explore the effects and mechanisms by which FA regulates oxidative stress in cells, with the aim of providing a theoretical foundation for improving the reproductive performance of cows. The results show that, compared with the H2O2 group, the FA+ H2O2 group showed an increase in the cell proliferation index (PI), superoxide dismutase 2 (SOD2), glutathione peroxidase (GSH-px), and catalase (CAT) mRNA expression and total antioxidant capacity (T-AOC) of cells, while the content of reactive oxygen species (ROS) decreased. In addition, the mRNA expression of tight junction factors, nutrient transporters, placental functional factors, mammalian rapamycin (mTOR) and its downstream factors, and nuclear factor erythroid 2-related factor 2 (NRF2) and its downstream factors in the FA+ H2O2 group increased, while the protein abundance of nuclear NRF2 decreased. After treatment with the inhibitor ML385, it was found that the protective effect of FA on H2O2-induced cellular oxidative damage was alleviated. These results indicate that FA can regulate the NRF2/mTOR signaling pathway, promote the expression of antioxidant factors, and alleviate the damage to the cell barrier and nutrient transport function in BPTCs caused by oxidative stress.

Lactic Acid Bacteria in Vinegar Fermentation: Diversity, Functionality and Health Benefits

Vinegar, frequently distilled by solid fermentation or liquid processes, was generated through the synergistic effect of a microbial community in open or semi-open environments. Based on the studied raw materials, researchers distributed the vinegar into three classes: grain, fruit and animal, with lactic acid bacteria (LAB) playing a pivotal role in their fermentation and contributing significantly to their functional and sensory qualities. Typically, the natural maturation of fresh vinegar necessitates a long period and vast space, engendering a reduced efficiency. To accelerate the vinegar aging process, some physical methods, viz. micro-oxygenation, ozone, ultrasound, microwave, gamma rays, infrared, electric fields and high pressure, have been developed. Produced or enriched by LAB, key bioactive vinegar components are organic acids, phenolic compounds, melanoidins, and tetramethylpyrazine. These active compounds have antibacterial, antioxidant, anti-inflammatory functions; aid in the regulation of liver protection metabolism and glucose control; and have blood pressure, anti-tumor, anti-fatigue and metabolic regulatory effects. The review explores advancements in vinegar production, including modernized fermentation processes and optimized aging techniques, which enhance these beneficial compounds and ensure product consistency and safety. By examining the LAB variety strains and the bioactive profiles of different vinegar types, this study highlights vinegar's value beyond a culinary product, as a potential therapeutic agent in human nutrition and health. The findings underscore vinegar's relevance not only in dietary and preventive healthcare but also as a potential functional food ingredient. Further research is needed to explore the mechanisms of action through which LAB contribute to the development of several new healthy vinegars.

Effects of chronic cold stress and thermal stress on growth performance, hepatic apoptosis, oxidative stress, immune response and gut microbiota of juvenile hybrid sturgeon (Acipenser baerii ♀ × A. schrenkii ♂)

The current study was conducted to investigate the effects of chronic cold stress and thermal stress on the growth performance, hepatic oxidative status, immune response, apoptosis and gut microbiota in juvenile hybrid sturgeon. The fish (initial mean weight: 21.4 ± 0.3 g) was reared at three temperatures (14 °C, 22 °C, and 30 °C) for 16 d, which were termed as low temperature group (LT), moderate temperature group (MT), and high temperature group (HT), respectively, and the second group was regarded as control group in this study. Each group was assigned randomly to three tanks with 15 fish per replica. The results indicated that cold stress resulted in a significant reduction of growth metrics and a significant increase of feed conversion ratio in fish compared with MT group. Interestingly, cold stress increased hepatocyte apoptosis revealed by TUNEL staining, along with nuclear disappearance in H&E-stained sections and elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Transcriptional levels of apoptosis-related genes and toll-like receptor signaling pathway components were significantly up-regulated in liver under cold stress. Compared with control group, in terms of thermal stress, the growth performance and feed utilization of fish were declined to some extent compared with MT group. Moreover, high temperature significantly elevated hepatic productions of malondialdehyde and hydrogen peroxide, as well as increased activities of some antioxidant enzymes in liver. In addition, low and high temperature induce changes in the composition of gut microbiota. Overall, the results suggested that cold stress decelerated growth performance, induced hepatocyte apoptosis, and enhanced innate immunity in hybrid sturgeon to cope with additional stressors. Whereas, thermal stress resulted in hepatic oxidative stress in liver and the protective responses in the antioxidant enzymes in fish were activated. These results provided insights into the different physiological adaptation strategies in responsive to cold stress and thermal stress in this cold-water fish.

Metabolomics and ionomics reveal the quality differences among peach, acacia and karaya gums

Despite the diverse industrial applications and health benefits of plant gums, significant variations in quality among different types remain underexplored. This study investigates the differences in antioxidant activity, mineral elements, and metabolic profiles among peach, acacia, and karaya gums. Our findings reveal significant differences in total phenol content, with peach gum exhibiting the highest (20.41 μmol/g), followed by acacia gum (3.94 μmol/g) and karaya gum (1.24 μmol/g). Metabolomics and ionomics show that these gums were rich in a variety of small molecular metabolites, including amino acids, organic acids, flavonoids, and lipids, as well as numerous mineral elements. However, the concentrations of these compounds varied significantly across the different gum types. Specifically, peach gum contained higher levels of small-molecule organic acids (such as citric, quinic, and azelaic acids) and flavonoids. In contrast, acacia gum was characterized by a higher content of central amino acids (glutamic and aspartic acids), aromatic amino acids (tyrosine, phenylalanine and tryptophan) and alkaloids (trigonelline, spermidine and spermine). Karaya gum exhibited higher levels of lipids (including palmitic, linoleic, and tetradecanoic acids) and minerals (such as Ca, S, Mg and Fe). Notably, pesticide residues, including thiamethoxam, propiconazole, and difenoconazole, were detected in peach gum, indicating potential health risks. These findings provide valuable insights into the quality analysis of plant gums and the exploration of their functional components.

Inflammation-Targeted Biomimetic Nano-Decoys via Inhibiting the Infiltration of Immune Cells and Effectively Delivering Glucocorticoids for Enhanced Multiple Sclerosis Treatment

Excessive infiltration of neutrophil and inflammatory cytokines accumulation as well as the inadequate delivery of drugs to the targeted site are key pathological cascades in multiple sclerosis (MS). Herein, inflammation-targeting biomimetic nano-decoys (TFMN) is developed that inhibit the infiltration of immune cells and effectively deliver glucocorticoids to lesions for enhanced MS treatment. Nano-decoys encapsulated with the glucocorticoid methylprednisolone (MPS) are prepared by coating neutrophil membrane (NM) on nanoparticles formed by the self-assembly of tannic acid and poloxamer188/pluronic68. Benefiting from the natural inflammation-targeting ability of activated neutrophil membranes, TFMN can target the lesion site and prevent neutrophils infiltration by adsorbing and neutralizing elevated neutrophil-related cytokines, subsequently modulating the inflammatory microenvironment in experimental autoimmune encephalomyelitis mice. TFMN exhibits a strong antioxidant capacity and scavenged excessive reactive oxygen species to enhance neuronal protection. Furthermore, at the inflammation site, perforin, discharged by cytotoxic T-lymphocytes, triggered the controlled release of MPS within the TFMN through perforin-formed pores in the NM. Simultaneously, this mechanism protected neurons from perforin-induced toxicity. The MPS liberated at the targeted site achieves optimal drug accumulation, thereby enhancing therapeutic efficacy. In conclusion, the innovative system shows potential for integrating various therapeutic agents, offering a novel strategy for CNS disorders.

Unlocking the potential of persimmons: A comprehensive review on emerging technologies for post-harvest challenges, processing innovations, and prospective applications

Persimmons are widely acknowledged as a valuable source of both medicinal and nutritional components, providing a diverse spectrum of nutrients and phytochemicals. Despite these benefits, biases against persimmons persists due to their characteristic astringent flavor that sets them apart from other fruits. Although several studies have explored various aspects of persimmons, a comprehensive review that addresses post-harvest challenges, processing innovations, and potential applications is notably absent in the literature. This review aims to fill this gap by discussing a range of topics, including emerging preservation technologies, methods for detecting and eliminating astringency, identification of functional elements, health-promoting prospects, and advancements in processed persimmon products. The primary objective is to enhance the utilization of persimmons and promote the development of diverse, customized products, thereby fostering the emergence of functional and futuristic foods.

Investigation of bioactive compounds and their correlation with the antioxidant capacity in different functional vinegars

There are complex and diverse substances in traditional vinegars, some of which have been identified as biologically active factors, but the variety of functional compounds is currently restricted. In this study, it was aimed to determine the bioactive compounds in 10 typical functional vinegars. The findings shown that total flavonoids (0.21-7.19 mg rutin equivalent/mL), total phenolics (0.36-3.20 mg gallic acid equivalent/mL), and antioxidant activities (DPPH: 3.17-47.63 mmol trolox equivalent/L, ABTS: 6.85-178.29 mmol trolox equivalent/L) varied among different functional vinegars. In addition, the concentrations of the polysaccharides (1.17-44.87 mg glucose equivalent/mL) and total saponins (0.67-12.46 mg oleanic acid equivalent/mL) were determined, which might play key role for the function of tested vinegars. A total of 8 organic acids, 7 polyphenol compounds and 124 volatile compounds were measured and tentatively identified. The protocatechuic acid (4.81-485.72 mg/L), chlorogenic acid (2.69-7.52 mg/L), and epicatechin (1.18-97.42 mg/L) were important polyphenol compounds in the functional vinegars. Redundancy analysis indicated that tartaric acid, oxalic acid and chlorogenic acid were significantly positively correlated with antioxidant capacity. Various physiologically active ingredients including cyclo (Pro-Leu), cyclo (Phe-Pro), cyclo (Phe-Val), cyclo (Pro-Val), 1-monopalmitin and 1-eicosanol were firstly detected in functional vinegars. Principle component analysis revealed that volatiles profile of bergamot Monascus aromatic vinegar and Hengshun honey vinegar exhibited distinctive differences from other eight vinegar samples. Moreover, the partial least squares regression analysis demonstrated that 11 volatile compounds were positively correlated with the antioxidant activity of vinegars, which suggested these compounds might be important functional substances in tested vinegars. This study explored several new functionally active compounds in different functional vinegars, which could widen the knowledge of bioactive factor in vinegars and provide new ideas for further development of functional vinegar beverages.

Hepatoprotective Activity and Mechanisms of Prenylated Stilbenoids

Dietary prenylated stilbenoids, found in various food sources, offer multiple health benefits, including liver protection. However, the underlying mechanisms of hepatoprotection remain unclear. In this study, we synthesized 13 natural prenylated stilbenoids and examined their hepatoprotective activities, with silent mating type information regulation 2 homologue-1 (SIRT1) as the primary target for screening. Among all of the prenylated stilbenoids tested, 4-C-geranyl oxyresveratrol demonstrated superior performance. It activated SIRT1 activity more effectively than resveratrol, a well-known SIRT1 activator. To further investigate the mechanism of liver protection, two in vitro models were used: the palmitic acid-induced lipid accumulation model and the H2O2-induced apoptosis model. Our findings suggested that 4-C-geranyl oxyresveratrol mitigated lipid accumulation through the SIRT1-PGC1α pathway, reduced apoptosis via the SIRT1-p53-p21 pathway, and exerted antioxidant effects through the SIRT1-Nrf2 pathway. These findings provide new insights into the chemical basis of the health benefits of prenylated stilbenoids and their potential use as functional food additives.

Photochemoprevention of topical formulation containing purified fraction of Inga edulis leaves extract

Natural antioxidants have attracted attention for their therapeutic use as photochemopreventive agents. Inga edulis leaves extract and its purified fraction have high polyphenolic content and high antioxidant capacity. In addition, they presented UV photostability and low citotoxicity in fibroblast cells. In this context, this study first aimed at development of topical formulation containing purified fraction of I. edulis extract and the evaluation of skin penetration of the compounds. Moreover, the photoprotective/photochemopreventive potential of the formulation containing I. edulis purified fraction were investigated in vitro and in vivo. The topical formulation containing 1% of the purified fraction of I. edulis increased the endogenous antioxidant potential of the skin, and vicenin-2 and myricetin compounds were able to penetrate the epidermis and dermis. Additionally, the purified fraction (25 and 50 mg/mL) showed a photoprotective effect against UVA and UVB radiation in L929 fibroblast cells. In vivo studies have shown that the formulation added with purified fraction provided an anti-inflammatory effect on the skin of animals after UVB exposure, since it was observed a reduction in MPO activity, IL-1β and TNF-α cytokines, and CXCL1/KC chemokine concentrations. In conclusion, the purified fraction of I. edulis, rich in phenolic compounds, when incorporated in topical formulation, appears as an alternative to prevent skin damages induced by UV radiation, due to its antioxidant and anti-inflammatory properties.

Identification and preparation of selenium-containing peptides from selenium-enriched Pleurotus eryngii and their protective effect on lead-induced oxidative damage in NCTC1469 hepatocytes

BACKGROUND

Lead (Pb) is a highly toxic and persistent substance that easily accumulates in living organisms, eliciting cellular toxicity and oxidative stress. Some selenium-containing proteins and peptides prepared from plant extracts are beneficial for protecting the body's health and resisting external disturbances. In the present study, selenium-containing peptide species were prepared from selenium-enriched Pleurotus eryngii protein hydrolysates and to evaluate the benefits of selenium-containing peptides on Pb-induced oxidative stress in NCTC1469 hepatocytes.

RESULTS

Trypsin was selected as primary enzyme to hydrolyze the selenium-enriched protein (SPH). The optimal hydrolysis conditions were: hydrolysis time, 1.5 h; initial pH 8.0. The SPH was digested by trypsin and then purified by ultrafiltration, gel filtration chromatography and reversed-phase HPLC to obtain the selenium-containing peptides SPH-I-2. Furthermore, SPH-I-2 was analyzed and a number of total 12 selenium-containing peptides were identified by liquid chromatography-tandem mass spectroscopy. The NCTC1469 cell culture study showed that selenium-containing peptides were capable of reducing reactive oxygen species levels and regulating the Keap1/Nrf2 pathway by upregulating Nrf2, HO-1, GCLC, GCLM and NQO1 genes and downregulating Keap1 genes. Moreover, selenium-containing peptides were also able to suppress Pb-induced elevated levels of nitric oxide (NO), lactate dehydrogenase (LDH), malondialdehyde (MDA), increase antioxidant enzyme activity and alleviate cell apoptosis.

CONCLUSION

The present study indicated that the selenium-containing peptides could protect cells from Pb²⁺ -induced oxidative stress. © 2023 Society of Chemical Industry.

Structural characterization of polysaccharides after fermentation from Ganoderma lucidum and its antioxidant activity in HepG2 cells induced by H2O2

In this study, Lactiplantibacillus plantarum ATCC14917 was used to ferment Ganoderma lucidum spore powder. Two polysaccharides were purified from unfermented (GLP) and fermented (FGLP) Ganoderma lucidum spore powder. The chemical structure and antioxidant activity of the polysaccharides were studied. Finally, the effect of GLP and FGLP on the oxidative stress regulation pathway in HepG2 cells was explored. The results showed that the main structural characteristics of Ganoderma lucidum polysaccharides remained unchanged during the fermentation. However, the average molecular weight (M_w) of Ganoderma lucidum polysaccharides decreased from 1.12 × 10⁵ Da to 0.89 × 10⁵ Da. Besides this, the contents of mannose, galactose, and glucuronic acid increased, while the contents of xylose and glucose were decreased. In addition, the content of uronic acid was raised, and the apparent structure was changed from smooth and hard to porous and loose. In antioxidant studies, intracellular ROS and MDA contents in the oxidative stress model were decreased, and T-AOC content was increased under GLP and FGLP intervention. In the investigation of the regulation pathway, Nrf-1 gene expression was up-regulated, and Keap1 gene expression was down-regulated under GLP and FGLP intervention. The antioxidant genes NQO1 and NO-1 expressions were increased to activate the activities of antioxidant enzymes CAT, SOD and GSH-PA to resist oxidative stress. Compared with GLP, FGLP has a stronger regulatory role in this pathway, thus showing more potent antioxidant activity. This experiment is beneficial to the further utilization of Ganoderma lucidum spore powder.

Enzymatic acylation improves the stability and bioactivity of lutein: Protective effects of acylated lutein derivatives on L-O2 cells upon H2O2-induced oxidative stress

The instability of lutein has limited its wide application especially in the food industry. In this study, enzymatic acylation of lutein with divinyl adipate was investigated. Three new acylated lutein derivatives, lutein-3-O-adipate (compound 1), lutein-3'-O-adipate (compound 2) and lutein-di-adipate (compound 3), were identified and their stabilities and bioactivates were evaluated. Notably, compounds 1-3 showed better thermal, light stability and stronger scavenging capacity to ABTS radical cation (ABTS⁺) and hydroxyl radical (OH). Most importantly, these acylated lutein derivatives exhibited excellent protective effects on L-O2 cells upon hydrogen peroxide (H₂O₂)-induced oxidative stress. In particular, the acylated lutein derivative termed compound 3 prevented cellular oxidative stress via restraining the overproduction of reactive oxygen species (ROS), thereby increasing related antioxidant enzymes activity and inhibiting apoptosis by mitochondria pathway. Our research provides important insights into the application of acylated lutein derivatives in food, cosmetic, and pharmaceutical products.

Effect of Pesticide Vinclozolin Toxicity Exposure on Cardiac Oxidative Stress and Myocardial Damage

(1) Background: Vinclozolin is a popular fungicide used in fruit, ornamental plants, and vegetable crops. It has recently been seen that prolonged exposure to VZN can cause human or animal health damage to various organs, but little is known to date about its cardiovascular effects. In this study, we addressed the chronic effects of VZN on the myocardium and the enzymes involved in the cardiovascular function. (2) Methods: The animals were divided into four groups: group 1 served as the control, group 2 received 1 mg/kg of VZN by gavage, group 3 received 30 mg/kg of VZN by gavage, and group 4 received 100 mg/kg of VZN by gavage, for 30 days. (3) Results: Results showed that 100 mg/kg VZN markedly increased the plasma concentration of cardiac markers (CK-MB, cTnT, ANP, BNP). Moreover, compared to the control group, VZN treatment decreased the activity of SOD, CAT, and GPx, and downregulated the mRNA expression levels of Nrf2. Furthermore, collagen deposition was amplified owing to 100 mg/kg VZN cardiotoxicity. This harmful effect was confirmed by a histological study using hematoxylin and eosin (H&E) and Masson's trichrome staining. (4) Conclusion: Overall, our results proved the cardiotoxicity caused by chronic exposure to VZN.

Neuroprotective Effects of a Novel Tetrapeptide SGGY from Walnut against H2O2-Stimulated Oxidative Stress in SH-SY5Y Cells: Possible Involved JNK, p38 and Nrf2 Signaling Pathways

SGGY, an antioxidant tetrapeptide identified from walnut protein hydrolysate in our previous study, has been suggested to possess the potential to alleviate oxidative stress in cells. In this paper, the neuroprotective effects of SGGY on H2O2-stimulated oxidative stress in SH-SY5Y cells and the underlying mechanisms were investigated. Results showed that SGGY alleviated H2O2-induced oxidative stress by decreasing the intracellular reactive oxygen species (ROS) level and altering the mitochondrial membrane potential (MMP), thereby inhibiting apoptosis and increasing cell viability. SGGY significantly restored antioxidant enzyme activities and reduced malondialdehyde (MDA) content accordingly. Moreover, SGGY promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and suppressed the H2O2-induced activation of JNK and p38 mitogen-activated protein kinases (MAPKs). Taken together, these results suggested that SGGY protected SH-SY5Y cells from H2O2-provoked oxidative stress by enhancing the ability of cellular antioxidant defense, and the possible mechanism involved MAPKs and Nrf2 signaling pathways.

Protective Effect of Peptides from Pinctada Martensii Meat on the H2O2-Induced Oxidative Injured HepG2 Cells

Pinctada martensii is a major marine pearl cultured species in southern China, and its meat is rich in protein, which is an excellent material for the preparation of bioactive peptides. In this study, the peptides from Pinctada martensii meat were prepared by simulated gastrointestinal hydrolysis, and after multistep purification, the structures of the peptides were identified, followed by the solid-phase synthesis of the potential antioxidant peptides. Finally, the antioxidant activities of the peptides were verified using HepG2 cells, whose oxidative stress was induced by hydrogen peroxide (H₂O₂). It was shown that the antioxidant peptide (S4) obtained from Pinctada martensii meat could significantly increase the cell viability of HepG2 cells. S4 could also scavenge reactive oxygen species (ROS) and reduce the lactate dehydrogenase (LDH) level. In addition, it could enhance the production of glutathione (GSH) and catalase (CAT) in HepG2 cells, as well as the expression of key genes in the Nrf2 signaling pathway. Three novel antioxidant peptides, arginine-leucine (RL), arginine-glycine-leucine (RGL), and proline-arginine (PR), were also identified. In conclusion, peptides from Pinctada martensii meat and three synthetic peptides (RGL, RL, PR) showed antioxidant activity and could have the potential to be used as antioxidant candidates in functional foods.

Unveiling major ethnopharmacological aspects of genus Diospyros in context to its chemical diversity: A comprehensive overview

Diospyros species (DS), "Ebenaceae," were known for their therapeutic uses in folk medicine since days of yore. Thereafter, scientific evidence related their health benefits to a myriad of chemical classes, for instance, naphthoquinones, flavonoids, tannins, coumarins, norbergenin derivatives, sterols, secoiridoids, sesquiterpenes, diterpenoids, triterpenoids, volatile organic compounds (VOCs), and carotenoids. The available literature showed that more than 200 compounds were isolated and identified via spectroscopic techniques. Many pharmacological activities of DS have been previously described, such as antioxidant, neuroprotective, antibacterial, antiviral, antiprotozoal, antifungal, antiinflammatory, analgesic, antipyretic and cosmeceutical, investigated, and confirmed through versatile in vitro and in vivo assays. Previous studies proved that genus Diospyros is a rich reservoir of valuable bioactive compounds. However, further comparative studies among its different species are recommended for more precise natural source-based drug discovery and clinical application. Accordingly, this review is to recall the chemical abundance and diversity among different members of genus Diospyros and their ethnopharmacological and pharmacological uses. PRACTICAL APPLICATIONS: Practically, providing sufficient background on both secondary metabolites divergence and pharmacological properties of genus Diospyros has many fruitful aspects. As demonstrated below, extracts and many isolated compounds have significant curative properties, which can lead to the discovery of pharmaceutically relevant alternative substitutes to conventional medicine. Consequently, molecular docking on various receptors can be applied. On the grounds, Naoxinqing tablets, a standardized herbal product containing D. kaki leaves extract, have been patented and recorded in Chinese Pharmacopeia as an approved Traditional Chinese Medicine (TCM) for the treatment of cerebro- and cardiovascular diseases, although the underlying mechanism remains under advisement. Moreover, the antimicrobial applications of DS are of considerable concern; since the widespread use of antibiotics resulted in different forms of bacterial resistance, hence, limiting and compromising effective treatment. In addition, as a result of contemporary rampant memory disorders, neuroprotective activities of different extracts of DS became of great emphasis.

Chronic Exposure to Vinclozolin Induced Fibrosis, Mitochondrial Dysfunction, Oxidative Stress, and Apoptosis in Mice Kidney

Vinclozolin is one of the most used fungicides in the control of fungi in fruits, vegetables, and ornamental plants. The effects of its exposure on different organs have been described, but information regarding its relevance to vinclozolin-induced nephrotoxicity is largely missing. This study focuses on the potential mechanism of vinclozolin-induced nephrotoxicity. CD1 male mice were administered vinclozolin (100 mg/kg) by oral gavage for 28 days. Vinclozolin administration decreased body weight over the treatment period and at the end of the experiment, increased the ratio of kidney weight to body weight and increased serum urea nitrogen and creatinine contents. Vinclozolin also induced histopathological alterations, including tubular dilatation and necrosis and impaired the integrity of the renal-tubular architecture and kidney fibrosis. The analyses conducted showed that vinclozolin administration altered the mRNA levels of mitochondrial function-related proteins (SIRT3, SIRT1, PGC-1α, TFAM, NRF1, VDAC-1, and Cyt c) and oxidative stress (increased lipid peroxidation and decreased total antioxidative capacity, catalase, and superoxide dismutase activities, glutathione levels, and glutathione peroxidase activity) in the kidneys. Furthermore, vinclozolin induced toxicity that altered Nrf2 signalling and the related proteins (HO-1 and NQO-1). Vinclozolin administration also affected both the extrinsic and intrinsic apoptotic pathways, upregulating the expression of proapoptotic factors (Bax, Caspase 3, and FasL) and downregulating antiapoptotic factor (Bcl-2) levels. This study suggests that vinclozolin induced nephrotoxicity by disrupting the transcription of mitochondrial function-related factors, the Nrf2 signalling pathway, and the extrinsic and intrinsic apoptotic pathways.

Yellow pigment from gardenia fruit: structural identification and evaluation of cytotoxic activity in HepG2 cells by induction of apoptosis

The preparation process of yellow pigment (YP) from gardenia (Gardenia jasminoides) fruit was investigated, and the main components of YP were characterized by liquid chromatography-time of flight-mass spectrometer/mass spectrometer (LC-TOF-MS/MS). Furthermore, cytotoxic activity in HepG2 cells by induction of apoptosis was also evaluated. The preparation results indicated that the color value of YP was 498.34, which was 8.6 times higher than crude YP. Fifteen compounds in YP were identified, and crocins were the predominant compounds. The cell experiment results showed that YP inhibited the proliferation of HepG2 cells in a time- and dose-dependent manner. Moreover, YP also inhibited HepG2 cells in G2/M stage, increased the level of intracellular reactive oxygen species (ROS), and enhanced cell apoptosis. Real-time quantitative polymerase chain reaction (RT-PCR) analysis revealed the up-regulation of caspase-3, 8, 9, and bax and down-regulation of bcl-2 in HepG2 cells. Overall, these findings suggested that YP had potential cytotoxic activity in HepG2 cells by induction of apoptosis, which might be beneficial to human health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01133-9.

Evaluation of Proanthocyanidins from Kiwi Leaves (Actinidia chinensis) against Caco-2 Cells Oxidative Stress through Nrf2-ARE Signaling Pathway

Proanthocyanidins (PAs) are considered to be effective natural byproduct and bioactive antioxidants. However, few studies have focused on their mode of action pathways. In this study, reactive oxygen species (ROS), oxidative stress indices, real-time PCR, Western blotting, confocal microscopy, and molecular docking were used to investigate the protective effect of purified kiwi leaves PAs (PKLPs) on Caco-2 cells’ oxidative stress mechanisms. The results confirmed that pre-treatment with PKLPs significantly reduced H2O2-induced oxidative damage, accompanied by declining ROS levels and malondialdehyde (MDA) accumulation in the Caco-2 cells. The PKLPs upregulated the expression of antioxidative enzymes (GSH-px, CAT, T-SOD) and the relative mRNA (Nrf, HO-1, SOD-1, CAT) of the nuclear factor erythroid 2-related factor (Nrf2) signaling pathway. The protein-expressing level of the Nrf2 and its relative protein (NQO-1, HO-1, SOD-1) were significantly increased (p < 0.05) in the PKLPs pre-treatment group compared to the model group. In conclusion, the novelty of this study is that it explains how PKLPs’ efficacy on the Nrf2-ARE signaling pathway, in protecting vital cells from oxidative stress, could be used for cleaner production.

The Effects of Dietary Arthrospira platensis on Oxidative Stress Response and Pigmentation in Yellow Catfish Pelteobagrus fulvidraco

In aquaculture, fish are often exposed to several stress conditions, which will cause oxidative disorder and bring about health and quality problems. Arthrospira platensis contains abundant bioactive ingredients, which are beneficial for animal health. This study was conducted to investigate the effects of A. platensis on pigmentation, antioxidant capacity, and stress response after air exposure of fish. A total of 120 yellow catfish Pelteobagrus fulvidraco (initial weight 70.19 ± 0.13 g) were divided into three tanks per treatment and fed diets supplemented with 0 g kg−1 A. platensis (CON) and 20 g kg −1 A. platensis (AP) for 65 days. The results indicated that dietary A. platensis had no effects on the growth of yellow catfish. The AP diet significantly reduced lactic acid (LD) and cortisol levels stimulated by air exposure stress (p < 0.05). Dietary A. platensis significantly increased plasma superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities and glutathione (GSH) contents, and the relative expression levels of sod and cat, to protect against oxidative stress caused by air exposure (p < 0.05). The AP diet significantly improved the relative expression level of nrf2 (nuclear factor erythroid-2 related factor 2), while the relative expression level of keap1 (kelch-like ECH associated protein 1) was downregulated, and the protein levels of liver Nrf2 were significantly increased after air exposure stimuli (p < 0.05). Dietary A. platensis significantly increased skin lutein contents, increased skin redness, yellowness and chroma (p < 0.05), and improved body color abnormalities after oxidative stress caused by air exposure stimuli. Skin yellowness was associated with lutein contents and the expression levels of some antioxidant genes to varying degrees. Overall, dietary A. platensis could be utilized as a feed additive to activate the antioxidant response, as well as alleviate oxidative stress and pigmentation disorder induced by air exposure.

Acute ammonia exposure combined with heat stress impaired the histological features of gills and liver tissues and the expression responses of immune and antioxidative related genes in Nile tilapia

Ammonia exposure can be considered more stressful for aquatic animals when it coincides with high temperature. This study was conducted to detect the effects of ammonia exposure and heat stress and their interactions on the histological features of gills and liver tissues and the expression responses of immune and antioxidative related genes in Nile tilapia. Thus, 180 fish were divided into four groups (triplicates), where the first and third groups were kept in clean water without total ammonium nitrogen (TAN) exposure. At the same time, the second and fourth groups were exposed to 5 mg TAN/L. After seven days, the water temperature was raised in the third (without ammonia toxicity) and fourth (exposed with 5 mg TAN/L) groups up to 32 °C and kept under these conditions for 24 h. While the first (without ammonia toxicity) and second (exposed with 5 mg TAN/L) groups were kept under optimum water temperature (27.28 °C) then gills and liver tissues were dissected. Marked upregulation of keap1 was seen in the gills of fish exposed to ammonia/heat stress. The expression of mRNA levels for nrf2, nqo-1, cat, and gpx genes were downregulated in all stressed groups, with the lowest was recorded in the ammonia/heat stress group. The transcription of ho-1 was upregulated in the ammonia and heat stress groups while downregulated in the ammonia/heat stress group. The transcription of the complement C3 gene was downregulated in the livers of heat stress and ammonia/heat stress groups, while the lysozyme gene was downregulated in the ammonia/heat stress group. The mRNA expression levels of nf-κB, il-1β, and tnf-α genes were higher in the ammonia group than in the heat stress group. The highest transcription level of nf-κB, il-1β, tnf-α, il-8, and hsp70 genes and the lowest C3 and lysozyme genes were observed in fish exposed to ammonia/heat stress. The co-exposure to ammonia with heat stress triggered degeneration of primary and secondary gill filaments with telangiectasia and vascular congestion of secondary epithelium while, the liver showed hepatic vascular congestion and visible necrotic changes with nuclear pyknosis. In conclusion, the combined exposure of ammonia and heat stress induced oxidative stress, immunosuppression, and inflammation in Nile tilapia.

Effect of a Combination of Rosa canina Fruits and Apple Cider Vinegar against Hydrogen Peroxide-Induced Toxicity in Experimental Animal Models

Oxidative stress is the trigger of several diseases. It is an imbalance between the production of free radicals and antioxidants. This study aims to evaluate the antioxidant capacity and the protective property of Rosa canina fruits and apple cider vinegar combined or not against hydrogen peroxide (H2O2)-induced toxicity in Wistar rats. The experiment included five groups: group 1 received distilled water (10 mL/kg b.wt), group 2 received H2O2 10% (10 mL/kg b.wt), group 3 received H2O2 10% (10 mL/kg b.wt) and apple vinegar (2 mL/kg b.wt); group 4 received H2O2 10% (10 mL/kg b.wt) and apple vinegar supplemented with Rosa canina fruits extract (300 mg/kg b.wt); group 5 received H2O2 10% (10 mL/kg b.wt) and extract of Rosa canina fruits (300 mg/kg b.wt). The doses were given once daily via a gavage. The antioxidant capacity of apple vinegar and Rosa canina extract was analyzed, and AST, ALT, PAL, urea, and creatinine were determined on day 22 of the experiment. In addition, the kidney and the liver tissues were analyzed. The results showed that H2O2 caused a significant elevation of blood urea, blood creatinine, and transaminases. The histopathology examination revealed that H2O2 caused congestion, hemorrhage, and Bowman’s space enlarged. On the other hand, the results clearly showed that apple vinegar and Rosa canina fruits counterbalance the biochemical and histological changes induced by H2O2. In conclusion, the two natural products studied in this work are effective against the harmful effect of oxidative stress, which explains their use in traditional medicine.

Procyanidins: From Agro-Industrial Waste to Food as Bioactive Molecules

Procyanidins are an important group of bioactive molecules known for their benefits to human health. These compounds are promising in the treatment of chronic metabolic diseases such as cancer, diabetes, and cardiovascular disease, as they prevent cell damage related to oxidative stress. It is necessary to study effective extraction methods for the recovery of these components. In this review, advances in the recovery of procyanidins from agro-industrial wastes are presented, which are obtained through ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, pressurized fluid extraction and subcritical water extraction. Current trends focus on the extraction of procyanidins from seeds, peels, pomaces, leaves and bark in agro-industrial wastes, which are extracted by ultrasound. Some techniques have been coupled with environmentally friendly techniques. There are few studies focused on the extraction and evaluation of biological activities of procyanidins. The identification and quantification of these compounds are the result of the study of the polyphenolic profile of plant sources. Antioxidant, antibiotic, and anti-inflammatory activity are presented as the biological properties of greatest interest. Agro-industrial wastes can be an economical and easily accessible source for the extraction of procyanidins.

Biotechnological Processes in Fruit Vinegar Production

The production of fruit vinegars as a way of making use of fruit by-products is an option widely used by the food industry, since surplus or second quality fruit can be used without compromising the quality of the final product. The acetic nature of vinegars and its subsequent impact on the organoleptic properties of the final product allows almost any type of fruit to be used for its elaboration. A growing number of scientific research studies are being carried out on this matrix, and they are revealing the importance of controlling the processes involved in vinegar elaboration. Thus, in this review, we will deal with the incidence of technological and biotechnological processes on the elaboration of fruit vinegars other than grapes. The preparation and production of the juice for the elaboration of the vinegar by means of different procedures is an essential step for the final quality of the product, among which crushing or pressing are the most employed. The different conditions and processing methods of both alcoholic and acetic fermentation also affect significantly the final characteristics of the vinegar produced. For the alcoholic fermentation, the choice between spontaneous or inoculated procedure, together with the microorganisms present in the process, have special relevance. For the acetic fermentation, the type of acetification system employed (surface or submerged) is one of the most influential factors for the final physicochemical properties of fruit vinegars. Some promising research lines regarding fruit vinegar production are the use of commercial initiators to start the acetic fermentation, the use of thermotolerant bacteria that would allow acetic fermentation to be carried out at higher temperatures, or the use of innovative technologies such as high hydrostatic pressure, ultrasound, microwaves, pulsed electric fields, and so on, to obtain high-quality fruit vinegars.

Vinegar extract ameliorates alcohol-induced liver damage associated with the modulation of gut microbiota in mice

Vinegar extract is rich in phenolic compounds, which can prevent free radical-induced diseases. The aim of the present study was to explore the effects of vinegar extract on gut microbiota in alcohol-treated mice and their correlation with alcohol-induced liver damage. These results showed that vinegar extract regulated the gut microbiota composition and improved intestinal homeostasis through increasing the expression levels of ZO-1, occludin, claudin-1, Reg3b, and Reg3g in alcohol-treated mice. In addition, vinegar extract inhibited the alcohol-induced production of ROS and inflammatory factors. Moreover, Bacteroidetes, Verrucomicrobia, Akkermansia, and Lactobacillus showed a significant positive correlation with Reg3b, Reg3g, ZO-1, occludin, and claudin-1 and a negative correlation with hepatic inflammation and oxidative stress parameters. However, Firmicutes, Proteobacteria, Butyricimonas, Parabacteroides, and Bilophila exhibited the opposite effect. These findings suggest that vinegar extract modulates gut microbiota and improves intestinal homeostasis, and can be used as a novel gut microbiota manipulator against alcohol-induced liver damage.

Inhibitory Effect of Delphinidin on Oxidative Stress Induced by H2O2 in HepG2 Cells

Chronic liver diseases (CLDs) are correlated with oxidative stress induced by the accumulation of intracellular reactive oxygen species (ROS). In this study, we employed HepG2, a human liver carcinoma cell line containing many antioxidant enzymes, to explore the function of delphinidin against oxidative stress induced by H₂O₂ and to provide scientific data of the molecular mechanism. Cells were pretreated with different concentrations of delphinidin (10 μmol/L, 20 μmol/L, and 40 μmol/L) for 2 h before treatment with 750 μM H₂O₂ for 1 h. The results showed that H₂O₂ decreased the survival rate of HepG2 cells and increased the level of ROS, but delphinidin pretreatment could possess the opposite result. At the same time, the expression of Nrf2 was enhanced by the delphinidin pretreatment. This was because delphinidin promoted Nrf2 nuclear translocation and inhibited its degradation, which led to the increase expression of antioxidant protein HO-1 (Nrf2-related phase II enzyme heme oxygenase-1). Besides, we found that delphinidin could significantly alleviate the reduction of Nrf2 protein levels and the accumulation of intracellular ROS levels in Nrf2 knockdown HepG2 cells. In conclusion, our study suggested that delphinidin, as an effective antioxidant, protected HepG2 cells from oxidative stress by regulating the expression of Nrf2/HO-1.

Chronic exposure of hydrogen peroxide alters redox state, apoptosis and endoplasmic reticulum stress in common carp (Cyprinus carpio)

Hydrogen peroxide (H₂O₂) appears to be ubiquitous in natural water. Higher level of H₂O₂ can cause physiological stress, immunosuppression and even death in aquatic animals, but the physiological and molecular mechanisms of H₂O₂ toxicity are not well studied. Thus, the aim of the present study was to exposure potential toxic mechanisms of H₂O₂ via assessing the effects on redox state, apoptosis and endoplasmic reticulum (ER) stress in common carp. The fish were subjected to four concentrations of H₂O₂ (0, 0.25, 0.5 and 1 mM) for 14 days. And then, the tissues including blood, liver, muscle, gills, intestines, heart, kidney and spleen were collected to measure biochemical parameter and gene expression. The results showed that H₂O₂ exposure suppressed the majority antioxidative parameters in serum, liver, muscle and intestines, but enhanced T-SOD, CAT and T-AOC levels in gills. In all tested tissues, the MDA content was significantly promoted by H₂O₂ exposure. The oxidative stress-related genes including nrf2, gstα, sod, cat and/or gpx1 were upregulated in liver, gills, muscle, intestines, and/or kidney, but downregulated in heart after H₂O₂ exposure. Moreover, the ho-1 mRNA level was inhibited by H₂O₂ exposure in all tissues except intestines and spleen. After 14 days of exposure, H₂O₂ induced ER stress and initiated IRE1 and PERK pathways, which activated downstream genes, including chop, grp78 and/or xbp1s, to regulate UPR in liver, gills, muscle and/or heart. Meanwhile, H₂O₂ exposure activated MAPK pathway to regulate mitochondria-related genes including bcl-2, bax and cytc, which further triggered cas-8, cas-9 and cas-3, and accelerated apoptosis in liver, gills, muscle and heart. Importantly, in different tissues, the genes associated with oxidative stress, ER stress and apoptosis showed a different influence, and more significant influence was observed in the muscle, gills and liver. Overall results suggested that long-term H₂O₂ exposure induced oxidative stress, ER stress and apoptosis in the majority of tested tissues of common carp. The Nrf2, IRE1, PERK and MAPK pathways played important roles in H₂O₂-induced toxicity in fish. These data enriched the toxicity mechanism of H₂O₂ in fish, which might contribute to the risk assessment of H₂O₂ in aquatic environment.

Preparation of Antioxidant Protein Hydrolysates from Pleurotus geesteranus and Their Protective Effects on H2O2 Oxidative Damaged PC12 Cells

Pleurotus geesteranus is a promising source of bioactive compounds. However, knowledge of the antioxidant behaviors of P. geesteranus protein hydrolysates (PGPHs) is limited. In this study, PGPHs were prepared with papain, alcalase, flavourzyme, pepsin, and pancreatin, respectively. The antioxidant properties and cytoprotective effects against oxidative stress of PGPHs were investigated using different chemical assays and H2O2 damaged PC12 cells, respectively. The results showed that PGPHs exhibited superior antioxidant activity. Especially, hydrolysate generated by alcalase displayed the strongest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (91.62%), 2,2-azino-bis (3-ethylbenzothia zoline-6-sulfonic acid) (ABTS) radical scavenging activity (90.53%), ferric reducing antioxidant power, and metal ion-chelating activity (82.16%). Analysis of amino acid composition revealed that this hydrolysate was rich in hydrophobic, negatively charged, and aromatic amino acids, contributing to its superior antioxidant properties. Additionally, alcalase hydrolysate showed cytoprotective effects on H2O2-induced oxidative stress in PC12 cells via diminishing intracellular reactive oxygen species (ROS) accumulation by stimulating antioxidant enzyme activities. Taken together, alcalase hydrolysate of P. geesteranus protein can be used as beneficial ingredients with antioxidant properties and protective effects against ROS-mediated oxidative stress.

Nanoformulations to Enhance the Bioavailability and Physiological Functions of Polyphenols

Polyphenols are micronutrients that are widely present in human daily diets. Numerous studies have demonstrated their potential as antioxidants and anti-inflammatory agents, and for cancer prevention, heart protection and the treatment of neurodegenerative diseases. However, due to their vulnerability to environmental conditions and low bioavailability, their application in the food and medical fields is greatly limited. Nanoformulations, as excellent drug delivery systems, can overcome these limitations and maximize the pharmacological effects of polyphenols. In this review, we summarize the biological activities of polyphenols, together with systems for their delivery, including phospholipid complexes, lipid-based nanoparticles, protein-based nanoparticles, niosomes, polymers, micelles, emulsions and metal nanoparticles. The application of polyphenol nanoparticles in food and medicine is also discussed. Although loading into nanoparticles solves the main limitation to application of polyphenolic compounds, there are some concerns about their toxicological safety after entry into the human body. It is therefore necessary to conduct toxicity studies and residue analysis on the carrier.

Protective effect of Lachnum polysaccharide on dextran sulfate sodium-induced colitis in mice

Inflammatory bowel disease (IBD) has been gradually considered as a public health challenge worldwide. This study determined the protective effect of Lachnum polysaccharide (LEP) on dextran sulfate sodium (DSS)-induced experimental colitis in mice and explored the underlying mechanism. Results showed that dietary LEP reduced DSS-induced disease activity index (DAI), colon shortening and colonic tissue damage. LEP treatment restored intestinal barrier integrity by regulating the expression of tight junction proteins and mucus layer protecting proteins. Moreover, pro-inflammatory cytokine production was inhibited by LEP through regulating PPARγ/NF-κB and IL-6/STAT3 pathways and inhibiting inflammatory cell infiltration. In addition, LEP also inhibited (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation, endoplasmic reticulum (ER) stress and oxidative/nitrosative stress induced by DSS. These results provided a scientific basis for LEP as a potential natural agent for protecting mice from DSS-induced IBD.

Antioxidant and α-glucosidase inhibitory capacity of nonextractable polyphenols in Mopan persimmon

This study was to evaluate and compare the polyphenols contents, antioxidant capacities, and α-glucosidase inhibitory abilities of extractable and nonextractable polyphenols (EP and NEP) in Mopan persimmon. The results showed that total phenols content of NEP was 5 times higher than that of EP, and the hydrolyzed NEP compounds displayed higher antioxidant capacity than EP in vitro by DPPH, ORAC assays. Meanwhile, NEP also exhibited inhibition capacity of α-glucosidase and were higher than that of acarbose. In addition, an in vitro model of gastrointestinal digestion was used for the release of NEP, the polyphenols content and ORAC values were obviously increased in gastric digestion stage. The result indicated that NEP in Mopan persimmon, which has often been overlooked and discarded in the past, possessed higher polyphenols content and antioxidant capacity than EP.

Ultrasound processing of verjuice (unripe grape juice) vinegar: effect on bioactive compounds, sensory properties, microbiological quality and anticarcinogenic activity

Verjuice is one of the alternative fruit juices recently obtained from unripe grapes. In this study, the aim was primarily to optimize the process conditions for the enrichment of bioactive components in verjuice vinegar with ultrasound treatment. For this purpose, ultrasound treatment was applied to vinegar samples at different times (2, 4, 6, 8 and 10 min), different amplitudes (60%, 65%, 70%, 75% and 80%) and 26 kHz frequency. Total phenolic content (TPC), total flavonoid content (TFC), total antioxidant capacity (1,1-diphenyl-2-picrylhydrazyl (DPPH) and cupric reducing antioxidant capacity (CUPRAC) were evaluated for optimization (response surface methodology (RSM) and genetic algorithm (GA)) of process conditions. The sensory properties, microbiological quality and anticarcinogenic activity were then evaluated for the ultrasound-treated verjuice vinegar (UVV) (9.4 min and 68.7 amplitude result of RSM), traditional verjuice vinegar and pasteurized verjuice vinegar samples obtained from the optimization. At the end of the RSM optimization, CUPRAC (464.44 mg TEAC/mL), DPPH (0.694 mg TEAC/mL), TFC (70.85 mg CE/mL) and TPC (12.22 mg GAE/mL) were determined. RSM and GA results were found to be approximately the same. Analysis results showed that ultrasound-treated verjuice vinegar was enriched bioactive components compared to other samples. Verjuice vinegar showed anticarcinogenic effects. The UVV sample was generally appreciated in sensory evaluation. As a result, ultrasound treatment of verjuice vinegar was found to be successful.

Purification and identification of buckwheat hull flavonoids and its comparative evaluation on antioxidant and cytoprotective activity in vitro

Buckwheat hulls, by-products of buckwheat processing, contain various flavonoids, but the antioxidant capacity and synergy of different flavonoids are unclear. The purpose of this study was to evaluate the antioxidant activity of flavonoid monomers and high-flavonoid component (HBHF) in buckwheat hulls using chemical-based assays and cellular-based assays. Four kinds of flavonoids were identified as rutin, isoorientin, vitexin, and hyperoside from buckwheat hulls. In chemical-based assays, rutin and HBHF showed relatively high free radical scavenging activities and total antioxidant capacities. In cellular-based assays, however, HBHF showed much higher proliferation activity against cell damage than flavonoid monomers when HepG2 cell was oxidatively damaged by H2O2 or high glucose. The cytoprotective activities of flavonoid monomers and HBHF were closely associated with reducing levels of reactive oxygen species (ROS) and malondialdehyde (MDA) or increasing catalase (CAT) activity. In conclusion, buckwheat hull flavonoids are the favorable application candidates for natural antioxidants.

Interaction of dietary polyphenols and gut microbiota: Microbial metabolism of polyphenols, influence on the gut microbiota, and implications on host health

The human gastrointestinal tract is inhabited by a vast number of microorganisms that are called as the microbiota. Each individual harbors a unique gut microbial composition, this composition evolves throughout the host's lifetime and it is easily affected by internal or external changes. It has been shown that gut microbiota plays a crucial role in host's health and as this complex community has the ability to interact with each other and with the host's immune system, the presence or absence of some major species can affect the homeostasis. Diet can be considered as one of the pivotal factors in modulating the functionality, integrity, and composition of the gut microbiota as the gastrointestinal tract is the first organ exposed to components of the diet. In this review, we have focused on the effects of polyphenols, key compounds of a healthy diet with several biological activities, on the gut microbial composition, their biotransformation by the gut microbiota, and the effect of their reciprocal interactions in human health and disease.

Antioxidant effect of phenolic compounds (PC) at different concentrations in IEC-6 cells: A spectroscopic analysis

Phenolic compounds (PC) have been proposed as natural antioxidant agents that protect cells against oxidative stress-related diseases. Nonetheless, their low bioavailability forecasts controversy about mechanisms on their in vivo scavenging activity against reactive oxygen species (ROS). It has been proposed that PC reduce directly ROS concentration. An alternative or complementary action of PC could be the activation of the cell's antioxidant pathway, involving the regulation of gene expression, like that initiated by the Nrf2 transcription factor. To date there is not enough experimental data to support or discard this possibility. In the present study, we evaluated the use of several PC to prevent peroxidation of macromolecules and to elicit the activation of the Nrf2 transcription factor in H₂O₂-stresed IEC-6 enterocytic cell line. Synchrotron microspectroscopy demonstrated that PC compounds protected proteins, lipids and nucleic acids against oxidation induced by H₂O₂. Immunofluorescence results showed that treatment with quercetin (Qc), catechin (Cat) and capsaicin (Cap) induced the translocation of Nrf2 into the nucleus, at the same level as did H₂O₂ treatment, thus mimicking the action of the endogenous cell response to peroxidation. Even though the detailed mechanism still needs to be elucidated, we demonstrated the activation of Nrf2 by PCs in response to oxidative stress.

The Bioprotective Effects of Polyphenols on Metabolic Syndrome against Oxidative Stress: Evidences and Perspectives

Polyphenols are the general designation of various kinds of phytochemicals, mainly classified as flavonoids and nonflavonoids. Polyphenolic compounds have been confirmed to exhibit numerous bioactivities and potential health benefits both in vivo and in vitro. Dietary polyphenols have been shown to significantly alleviate several manifestations of metabolic syndrome, namely, central obesity, hypertension, dyslipidemia, and high blood sugar. This review is aimed at discussing the bioprotective effects and related molecular mechanisms of polyphenols, mainly by increasing antioxidant capacity or oxygen scavenging capacity. Polyphenols can exert their antioxidative activity by balancing the organic oxidoreductase enzyme system, regulating antioxidant responsive signaling pathways, and restoring mitochondrial function. These data are helpful for providing new insights into the potential biological effects of polyphenolic compounds and the development of future antioxidant therapeutics.

New pharmacological targets of three Asphodeline species using in vitro and ex vivo models of inflammation and oxidative stress

This study explored the efficacy of the methanolic extract of three Asphodeline species (A. damascena subsp. rugosa, A. tenuior subsp. tenuiflora var. tenuiflora, and A. cilicica) to protect against hydrogen peroxide (H₂O₂)-induced lactate dehydrogenase (LDH) activity in HCT116 cells, and also any protective effects against lipopolysaccharides (LPS)-induced nitrite levels, prostaglandin E2 (PGE2) and 8-iso-prostaglandin F2α (8-iso-PGF2α) levels, 5HIAA/5-HT ratio, tumor necrosis factor (TNF)-α and interleukin (IL)-6 gene expression in rat colon specimens. Interestingly, A. tenuior extract was most effective in improving the tested biomarkers, by reducing LDH activity and nitrite level. On the other hand, A. damascena was the only species able to blunt LPS-induced TNF-α gene expression in rat colon specimens. The present findings highlighted the protective effects of Asphodeline extracts via in vitro and ex vivo models of inflammation and oxidative stress, adding new insights to the pharmacological actions of these medicinal plant species. Abbreviations: IBD: inflammatory bowel disease; LPS: lipopolysaccharide; LDH: lactate dehydrogenase; 5HIAA: 5-hydroxyindoleacetic acid; 5-HT: 5-hydroxytryptamine.

Chrysanthemum extract attenuates hepatotoxicity via inhibiting oxidative stress in vivo and in vitro

Background

‘Bianliang ziyu’, a famous chrysanthemum variety commonly planted in Kaifeng, China, is often consumed by local residents. However, the hepatoprotective effects of Bianliang ziyu and their underlying mechanisms are not clear.

Objective

In this study, we investigated the hepatoprotective and antioxidative effects of Bianliang ziyu extract (BZE) on liver injury and explored its molecular mechanisms.

Design

Sprague-Dawley rats were administered BZE by intragastric administration for 8–9 days, and then alcohol or carbon tetrachloride (CCl₄) was administered by gavage to induce acute liver injury. The activities of serum alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, and malondialdehyde in the rats were measured, and the liver of each rat was examined for histopathological changes. In vitro, HL-7702 cells were pretreated with BZE for 24 h and then exposed to 30 mmol•L⁻¹ acetaminophen (APAP) for 12 h. The survival rate of the cells and the alanine aminotransferase and aspartate aminotransferase activities were determined. Then, we investigated the effects of BZE on oxidative stress, apoptosis, and the activation of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling in HL-7702 cells induced by APAP.

Results

The results showed that BZE prevented alcohol-, CCl₄-, and APAP-induced liver injury and suppressed hepatic oxidative stress in vitro and in vivo. BZE was also observed to significantly inhibit the reduction of mitochondrial membrane potential and regulate the expression of Bcl-2, Bax and Caspase-3 in APAP-induced HL-7702 cells. In addition, BZE significantly promoted nuclear translocation and the expression of Nrf2 as well as its downstream gene hemeoxygenase-1 (HO-1) in vitro. Furthermore, the findings showed that Nrf2 siRNA reversed the effects of BZE on cell survival and apoptosis-related protein expression in APAP-induced HL-7702 cells.

Conclusions

BZE plays an important role in preventing hepatotoxicity by inhibiting oxidative stress and apoptosis through activation of Nrf2 signaling. BZE could be developed as an effective functional food for protecting the liver.

Antioxidative, inflammatory and immune responses in hydrogen peroxide-induced liver injury of tilapia (GIFT, Oreochromis niloticus)

Oxidative stress has been implicated in the pathogenesis of many liver diseases in fish, but the molecular mechanism is still obscure. Here, we used hydrogen peroxide (H₂O₂) as a reactive oxygen species (ROS) to induce liver injury and assess underlying molecular mechanism linking oxidative stress and liver injury in fish. Tilapia were injected with various concentrations of H₂O₂ (0, 40, 120, 200, 300 and 400 mM) for 72 h. The blood and liver were collected to assay biochemical parameters and genes expression after 24, 48 and 72 h of injection. The results showed that treatments with higher H₂O₂ levels (300 and/or 400 mM) significantly increased the levels of GPT, GOT, AKP and MDA, and apparently decreased the levels of TP, ALB, SOD, GSH, CAT, GST and T-AOC throughout of the 72 h. The gene expression data showed that treatments with 200, 300 and/or 400 H₂O₂ suppressed Nrf2/keap1 pathway and its downstream genes including ho-1, nqo1 and gsta, activated inflammatory response via enhancing the mRNA levels of nf-κb, tnf-α, il-1β and il-8, and attenuating il-10 mRNA level, and caused immunotoxicity through downregulating the genes expression of c3, hep, lzm and Igm for 24, 48 and/or 72 h. Additionally, there was a mild or strong increase in levels of nrf2 and its subsequent antioxidant genes or enzymes such as ho-1, nqo1, gst, CAT and SOD in treatments with lower concentrations of H₂O₂ (40 or 120 mM) for 24 and/or 48 h. Overall results suggested that H₂O₂ hepatotoxicity was mainly concerned with lipid peroxidation, impairment antioxidant defense systems, inflammatory response and immunotoxicity, and Nrf2/Keap1 and NF-κB signaling pathways played important roles in oxidative stress-induced liver injury in fish.

Atrazine induced oxidative stress and mitochondrial dysfunction in quail (Coturnix C. coturnix) kidney via modulating Nrf2 signaling pathway

Atrazine (ATR) is a most used herbicide which is believed as a pivotal determinant of environmental nephrosis, but potential mechanism is still largely unclear. This study intends to reveal a novel mechanism of ATR-induced nephrotoxicity. Quail were treated with 0, 50, 250 and 500 mg ATR/kg/d by oral gavage for 45 days. Kidney coefficient was decreased, biochemical and morphologic indices reflecting the kidney injury were significantly increased in ATR-exposed quail. ATR exposure upregulated the expression of proapoptotic factors (Bax, Caspase 3 and FasL) and downregulated antiapoptotic factor (Bcl-2). Notably, cristae of mitochondria decreased, mitochondrial malformation and mitochondrial vacuolar degeneration were observed in ATR-exposed quail. ATR induced the disorder of mitochondrial function related factors expressions and promoted oxidative damage. Furthermore, ATR induced toxicities in the expression of Nrf2 and Nrf2-target genes. In conclusion, ATR altered the microstructure and function of quail kidney. ATR induced renal damage via causing mitochondrial dysfunction, influencing mitochondrial function related genes expression, modulating Nrf2 signaling pathway. This study suggested ATR induced the nephrotoxicity via disturbing the transcription of mitochondrial function related factors and Nrf2 signaling pathway.