Molecular and cellular responses to oxidative stress and changes in oxidation-reduction imbalance in the intestine

Microbial-transcriptome integrative analysis of heat stress effects on amino acid metabolism and lipid peroxidation in poultry jejunum

Despite the significant threat of heat stress to livestock animals, only a few studies have considered the potential relationship between broiler chickens and their microbiota. Therefore, this study examined microbial modifications, transcriptional changes and host-microbiome interactions using a predicted metabolome data-based approach to understand the impact of heat stress on poultry. After the analysis, the host functional enrichment analysis revealed that pathways related to lipid and protein metabolism were elevated under heat stress conditions. In contrast, pathways related to the cell cycle were suppressed under normal environmental temperatures. In line with the transcriptome analysis, the microbial analysis results indicate that taxonomic changes affect lipid degradation. Heat stress engendered statistically significant difference in the abundance of 11 microorganisms, including Bacteroides and Peptostreptococcacea. Together, integrative approach analysis suggests that microbiota-induced metabolites affect host fatty acid peroxidation metabolism, which is correlated with the gene families of Acyl-CoA dehydrogenase long chain (ACADL), Acyl-CoA Oxidase (ACOX) and Acetyl-CoA Acyltransferase (ACAA). This integrated approach provides novel insights into heat stress problems and identifies potential biomarkers associated with heat stress.

A Curcumin-Based Oral Gel Has Potential Protective Efficacy against Oral Mucositis: In Vitro Study

Oral mucositis is a common distressing complication of cancer therapy, characterised by painful sores within the oral cavity. Current management options offer limited symptomatic relief. Curcumin, a natural polyphenolic compound with recognised anti-inflammatory and antioxidant properties, has emerged as a potential protective agent against oral mucositis. This study explores the therapeutic potential of curcumin in mitigating the impact of oral mucositis by investigating a commercially available curcumin-based oral gel, PerioGold®. Liquid chromatography-tandem mass spectrometry was used to characterise the main constituents of PerioGold®. The cytotoxicity of curcumin constituent was investigated in four cell lines: primary oral keratinocytes (HOKs), immortalised oral keratinocytes (OKF6), dysplastic oral keratinocytes (DOKs), and oral squamous cell carcinoma cells (PE/CA-PJ15). Concentrations of hydrogen peroxide were optimised to develop in vitro models that mimic oral mucositis. The inhibitory effects of PerioGold® against the production of reactive oxygen species were assessed using a designated kit. OKF6 cells were the most sensitive to oxidative stress, while PE/CA-PJ15 cells showed the highest resistance. Pretreatment of the investigated cells for 24 h with PerioGold® demonstrated a significant antioxidative effect in all cells based on a dose-response pattern. PerioGold® exhibits clinical potential for protecting against oxidative stress, warranting further individualised clinical investigations.

Umbelliferone potentiates intestinal protective effect of Lactobacillus Acidophilus against methotrexate-induced intestinal injury: Biochemical and histological study

Intestinal injury is a common adverse effect of methotrexate (MTX) therapy, limiting its clinical use. Despite oxidative stress and inflammation being the most embedded mechanism of injury, pharmacological agents that exhibit antioxidant and anti-inflammatory impacts could prevent such toxicities. This study aimed to assess the enteroprotective effect of lactobacillus acidophilus (LB) and/or umbelliferone (UMB) against MTX-induced intestinal injury. Histologically, pretreatment with LB, UMB, or their combinations preserve the intestinal histological structure and mucin content with superior effect in combination therapy. In addition, oral pretreatment with UMB, LB, or their combinations significantly restored oxidant/antioxidant status, as evidenced by the upregulation of Nrf2, SOD3, HO-1, GSH, and GST levels concurrent with a decline in MDA contents. Besides, they suppressed the inflammatory burden by inhibiting STAT3, MPO, TLR4, NF-κB, TNF-α, and IL-6 levels. Moreover, LB, UMB, or their combinations significantly upregulated Wnt and β-catenin expression. Notably, pretreatment with the combination therapy is superior to monotherapy in protecting rats' small intestines from MTX-induced enteritis. In conclusion, combined pretreatment with LB and UMB could be a novel therapeutic regimen for conditions of intestinal injury induced by MTX via restoring oxidant/antioxidant balance and suppressing inflammatory burden.

Microplastic pollution in soils, plants, and animals: A review of distributions, effects and potential mechanisms

Increasing production of synthetic plastics and poor management of plastic wastes have dramatically increased the amount of plastics in the environment. In 2014, at the first United Nations Environment Assembly, marine plastic waste pollution was listed as one of the 10 most pressing environmental issues. In addition, there is much plastic waste in terrestrial ecosystems due to substantial residues from agricultural mulching and packing. As a recently recognized pollutant, microplastics (MPs) have attracted significant attention from the public and various governments. Concentrations of MPs in the environment vary among locations, from <100 to >1 × 10⁶ particles per cubic meter. Many studies have addressed the impacts and potential mechanisms of MPs on the environment and organisms. Humans and other organisms can ingest or carry MPs in a variety of passive ways and these MPs can have a range of negative effects on metabolism, function, and health. Additionally, given their large surface area, MPs can sorb various pollutants, including heavy metals and persistent organic pollutants, with serious implications for animals and human wellbeing. However, due to their complexity and a lack of accurate determination methods, the systematic impacts of MP pollution on whole foodwebs are not clearly established. Therefore, this review summarizes current research advances in MP pollution, particularly the impact of MPs on soils, plants, and animals, and proposes potential future research prospects to better characterize MPs.

R- Is Superior to S-Form of α-Lipoic Acid in Anti-Inflammatory and Antioxidant Effects in Laying Hens

The development of single enantiomers with high efficiency and low toxic activity has become a hot spot for the development and application of drugs and active additives. The aim of the present study was to investigate the effectiveness of the application of α-lipoic acid with a different optical rotation to alleviate the inflammation response and oxidative stress induced by oxidized fish oil in laying hens. Sixty-four 124-week-old Peking Red laying hens were randomly allocated to four groups with eight replicates of two birds each. The normal group was fed basal diets supplemented with 1% fresh fish oil (FO), and the oxidative stress model group was constructed with diets supplemented with 1% oxidized fish oil (OFO). The two treatment groups were the S-form of the α-lipoic acid model with 1% oxidized fish oil (OFO + S-LA) and the R-form of the α-lipoic acid model with 1% oxidized fish oil (OFO + R-LA) added at 100 mg/kg, respectively. Herein, these results were evaluated by the breeding performance, immunoglobulin, immune response, estrogen secretion, antioxidant factors of the serum and oviduct, and pathological observation of the uterus part of the oviduct. From the results, diets supplemented with oxidized fish oil can be relatively successful in constructing a model of inflammation and oxidative stress. The OFO group significantly increased the levels of the serum inflammatory factor (TNF-α, IL-1β, IL-6, and IFN-γ) and the oxidative factor MDA and decreased the activity of the antioxidant enzyme (T-AOC, T-SOD, GSH-Px, GSH, and CAT) in the oviduct. The addition of both S-LA and R-LA significantly reduced the levels of serum inflammatory factors (TNF-α, IL-1β, IL-6, and IFN-γ), increased the activity of antioxidant indexes (T-AOC, T-SOD, GSH-Px, GSH, and CAT), and decreased the MDA contents in the serum and oviduct. Meanwhile, the supplementation of S-LA and R-LA also mitigated the negative effects of the OFO on the immunoglobulins (IgA and IgM) and serum hormone levels (P and E2). In addition, it was worth noting that the R-LA was significantly more effective than the S-LA in some inflammatory (IL-1β) and antioxidant indices (T-SOD, GSH, and CAT). Above all, both S-LA and R-LA can alleviate the inflammation and oxidative damage caused by oxidative stress in aged laying hens, and R-LA is more effective than S-LA. Thus, these findings will provide basic data for the potential development of α-lipoic acid as a chiral dietary additive for laying hens.

Maturation- and degeneration-dependent articular cartilage metabolism via optical redox ratio imaging

From the two metabolic processes in healthy cartilage, glycolysis has been associated with proliferation and oxidative phosphorylation (oxphos) with matrix synthesis. Recently, metabolic dysregulation was significantly correlated with cartilage degradation and osteoarthritis progression. While these findings suggest maturation predisposes cartilage to metabolic instability with consequences for tissue maintenance, these links have not been shown. Therefore, this study sought to address three hypotheses (a) chondrocytes exhibit differential metabolic activity between immaturity (0-4 months), adolescence (5-18 months), and maturity (>18 months); (b) perturbation of metabolic activity has consequences on expression of genes pertinent to cartilage tissue maintenance; and (c) severity of cartilage damage is positively correlated with glycolysis and oxphos activity as well as optical redox ratio in postadolescent cartilage. Porcine femoral cartilage samples from pigs (3 days to 6 years) underwent optical redox ratio imaging, which measures autofluorescence of NAD(P)H and FAD. Gene expression analysis and histological scoring was conducted for comparison against imaging metrics. NAD(P)H and FAD autofluorescence both demonstrated increasing intensity with age, while optical redox ratio was lowest in adolescent samples compared to immature or mature samples. Inhibition of glycolysis suppressed expression of Col2, Col1, ADAMTS4, and ADAMTS5, while oxphos inhibition had no effect. FAD fluorescence and optical redox ratio were positively correlated with histological degeneration. This study demonstrates maturation- and degeneration-dependent metabolic activity in cartilage and explores the consequences of this differential activity on gene expression. This study aids our basic understanding of cartilage biology and highlights opportunity for potential diagnostic applications.

Comparison of structural and antioxidant activity of polysaccharide extracted from truffles

As the main component of truffles, polysaccharides have a variety of biological activities such as anti-oxidation, anti-tumor, and hypoglycemic activity, and these activities are closely related to its structure. In this study, Tuber Aestivum crude polysaccharide (TACP) and Tuber Melanosporum crude polysaccharide (TMCP) were obtained from Tuber Aestivum and Tuber Melanosporum by using microwave-assisted hot water, and then the Sephadex G-200 column was utilized to further separate and purify Tuber Aestivum polysaccharide (TAP) and Tuber Melanosporum polysaccharide (TMP) from TACP and TMCP. The structural characterization results showed that the molecular weight of TAP was 2.18 × 10⁴  kDa, while TMP was 8.79 × 10³  kDa. Although the two polysaccharide components were mainly composed of mannose (Man) and glucose (Glc), the molar ratio of Man and Glc in TAP was 14.76: 12.31, with a molar ratio of 5.43:10.94 in TMP. Furthermore, the antioxidant activity of two polysaccharide components was evaluated. TAP and TMP could protect porcine jejunal epithelial (IPEC-J2) cells from oxidative damage by H₂ O₂ , but TAP exhibited stronger antioxidant effects. It was mainly reflected that TAP could increase the secretion level of intracellular antioxidant enzymes (superoxide dismutase and catalase) in IPEC-J2 cells, and had a significant effect on the total antioxidant capacity of cells. The reactive oxygen species and malondialdehyde had better scavenging ability at the concentration of 20 µg/ml. The difference between TAP and TMP may be due to the dissimilar structure. Its structure-activity relationship needs further study. PRACTICAL APPLICATION: The structure of TAP and TMP were different, and TAP had higher molecular weight. Besides, TAP and TMP can protect IPEC-J2 cells from oxidative stress, providing a theoretical basis for developing potential antioxidant drugs of practical significance.

Curcumin and Intestinal Oxidative Stress of Pigs With Intrauterine Growth Retardation: A Review

Intrauterine growth restriction (IUGR) refers to the slow growth and development of a mammalian embryo/fetus or fetal organs during pregnancy, which is popular in swine production and causes considerable economic losses. Nutritional strategies have been reported to improve the health status and growth performance of IUGR piglets, among which dietary curcumin supplementation is an efficient alternative. Curcumin is a natural lipophilic polyphenol derived from the rhizome of Curcuma longa with many biological activities. It has been demonstrated that curcumin promotes intestinal development and alleviates intestinal oxidative damage. However, due to its low bioavailability caused by poor solubility, chemical instability, and rapid degradation, the application of curcumin in animal production is rare. In this manuscript, the structural-activity relationship to enhance the bioavailability, and the nutritional effects of curcumin on intestinal health from the aspect of protecting piglets from IUGR associated intestinal oxidative damage were summarized to provide new insight into the application of curcumin in animal production.

Lipoamide Alleviates Oxidized Fish Oil-Induced Host Inflammatory Response and Oxidative Damage in the Oviduct of Laying Hens

Fish oil (FO) is an important source of lipid in functional food and aquafeeds. However, the harmful effects of oxidized fish oil (OFO) on host metabolism and reproductive health are not yet clear. In addition, lipoamide (LAM) has been widely studied as an agent for alleviating various diseases associated with oxidative disruption. Therefore, in the current study, to investigate the effects of LAM in alleviating OFO-induced decline in reproductive performance and oxidative damage to the oviduct in laying hens. We constructed a 1% fresh FO model, a 1% OFO model, and a LAM model with 1% OFO (OFO + LAM) added at 100 mg/kg to explore the antioxidant effect of LAM. Herein, these results were evaluated by breeding performance, immune responses, estrogen, and antioxidant indices of serum samples, as well as the number of follicles and antioxidant parameters of oviducts. From the results, compared with the FO group, OFO significantly decreased the egg-laying rate, increased the contents of total protein (TP) and inflammatory factors [tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-8, and interferon γ (INF-γ)], and reduced the concentrations of anti-oxidation [total antioxidant (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), glutathione (GSH), glutathione reductase (GR), catalase (CAT), and hydroxyl radical scavenging activity (HRSA)] in serum samples, as well as reduced the levels of anti-oxidation indexes in oviduct tissues (p < 0.05). Of note, the supplementation of LAM could significantly increase the laying performance, improve the levels of serum immunoglobulins (IgA, IgG, and IgM), serum estrogen [progesterone (P) and estradiol (E2)], and serum antioxidant parameters (T-AOC, T-SOD, GSH-Px, GSH, GR, CAT, and HRSA) and decrease the concentrations of serum inflammatory cytokines (TNF-α, IL-6, IL-8, and INF-γ) in laying hens following OFO administration (p < 0.05). In addition, LAM could dramatically increase the contents of antioxidant factors (p < 0.05) in oviducts and enhance the secretion capacity of the uterine part. Taken together, OFO caused host metabolic dysfunction, oxidative damage, uterine morphological abnormalities, and alterations of ovarian function. These results suggested that LAM administration could alleviate host metabolic dysfunctions and inflammatory damage, and then ameliorate oxidative damage in the oviduct induced by OFO, ultimately improving reproductive function.

New pectic polysaccharides from Codonopsis pilosula and Codonopsis tangshen: structural characterization and cellular antioxidant activities

BACKGROUND

Codonopsis pilosula and Codonopsis tangshen are plants widely used in traditional Chinese medicine. Two pectic polysaccharides from the roots of C. pilosula and C. tangshen named as CPP-1 and CTP-1 were obtained by boiling water extraction and column chromatography.

RESULTS

The core structures of both CPP-1 and CTP-1 comprise the long homogalacturonan region (HG) as the backbone and the rhamnogalacturonan I (RG-I) region as the side chains. CPP-1 has methyl esterified galacturonic acid units and a slightly lower molecular weight than CTP-1. Biological testing suggested that CPP-1 and CTP-1 can protect IPEC-J2 cells against the H₂ O₂ -induced oxidative stress by up-regulating nuclear factor-erythroid 2-related factor 2 and related genes in IPEC-J2 cells. The different antioxidative activities of polysaccharides from different source of C. pilosula may be result of differences in their structures.

CONCLUSION

All of the results indicated that pectic polysaccharides CPP-1 and CTP-1 from different species of C. pilosula roots could be used as a potential natural antioxidant source. These findings will be valuable for further studies and new applications of pectin-containing health products. © 2021 Society of Chemical Industry.

Pectic polysaccharide from Nelumbo nucifera leaves promotes intestinal antioxidant defense in vitro and in vivo

In this study, the Nelumbo nucifera leaf polysaccharide (NNLP) was isolated by hot water extraction and ethanol precipitation. DEAE anion exchange chromatography and gel filtration were further performed to obtained the purified fraction NNLP-I-I, the molecular weight of which was 16.4 kDa. The monosaccharide composition analysis and linkage units determination showed that the fraction NNLP-I-I was a pectic polysaccharide. In addition, the NMR spectra analysis revealed that NNLP-I-I mainly consisted of a homogalacturonan backbone and rhamnogalacturonan I, containing a long HG region and short RG-I region, with AG-II and 1-3 linked rhamnose as side chains. The biological studies demonstrated that NNLP-I-I displayed antioxidant properties through mediating the Nrf2-regulated intestinal cellular antioxidant defense, which could protect cultured intestinal cells from oxidative stress and improve the intestinal function of aged mice.

Resveratrol and its derivative pterostilbene ameliorate intestine injury in intrauterine growth-retarded weanling piglets by modulating redox status and gut microbiota

Background

Intestinal disorder is an important factor contributing to growth lag and high rates of morbidity and mortality of piglets with intrauterine growth retardation (IUGR). Resveratrol (RSV) and its derivative pterostilbene (PT) are natural stilbenes possessing various bioactivities, such as antioxidative and anti-inflammatory effects. This study compared the protective potential of RSV and PT on the intestinal redox status and gut microbiota in weanling piglets with IUGR.

Methods

Eighteen male piglets of normal body weight (NBW) and 54 same-sex IUGR piglets were chosen according to their birth and weaning weights. The NBW piglets accepted a basal diet, while the IUGR piglets were allotted to one of three groups according to their body weight at weaning and received a basal diet, an RSV-supplemented diet (300 mg/kg), or a PT-supplemented diet (300 mg/kg), respectively.

Results

Compared with IUGR piglets, both RSV and PT improved the IUGR-associated decrease in jejunal villus height and increases in plasma diamine oxidase activity and D-lactate level and jejunal apoptosis of piglets (P < 0.05). Administering RSV and PT also enhanced jejunal superoxide dismutase activity and the mRNA and protein expression of superoxide dismutase 2 of IUGR piglets by promoting nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation (P < 0.05). Comparatively, PT was more effective than RSV in elevating the villus height/crypt depth ratio and occludin mRNA and protein levels in the jejunum of IUGR piglets (P < 0.05). PT was also superior to RSV in increasing Nrf2 nuclear translocation and inhibiting malondialdehyde accumulation in the jejunum of IUGR piglets (P < 0.05). Additionally, RSV modulated the composition of cecal microbiota of IUGR piglets, as evidenced by increasing the prevalence of the phylum Bacteroidetes and the genera Prevotella, Faecalibacterium, and Parabacteroides and inhibiting the growth of the phylum Proteobacteria and its genera Escherichia and Actinobacillus (P < 0.05). Moreover, RSV significantly increased the butyrate concentration in the cecum of IUGR piglets (P < 0.05).

Conclusion

PT is more potent than RSV to prevent intestinal oxidative stress, while RSV has a stronger capacity to regulate gut microbiota compared to PT.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-021-00589-9.

Effect of pluronic block polymers and N-acetylcysteine culture media additives on growth rate and fatty acid composition of six marine microalgae species

Abstract

The efficiency of microalgal biomass production is a determining factor for the economic competitiveness of microalgae-based industries. N-acetylcysteine (NAC) and pluronic block polymers are two compounds of interest as novel culture media constituents because of their respective protective properties against oxidative stress and shear-stress-induced cell damage. Here we quantify the effect of NAC and two pluronic (F127 and F68) culture media additives upon the culture productivity of six marine microalgal species of relevance to the aquaculture industry (four diatoms-Chaetoceros calcitrans, Chaetoceros muelleri, Skeletonema costatum, and Thalassiosira pseudonana; two haptophytes-Tisochrysis lutea and Pavlova salina). Algal culture performance in response to the addition of NAC and pluronic, singly or combined, is dosage- and species-dependent. Combined NAC and pluronic F127 algal culture media additives resulted in specific growth rate increases of 38%, 16%, and 24% for C. calcitrans, C. muelleri, and P. salina, respectively. Enhanced culture productivity for strains belonging to the genus Chaetoceros was paired with an ~27% increase in stationary-phase cell density. For some of the species examined, culture media enrichments with NAC and pluronic resulted in increased omega-3-fatty acid content of the algal biomass. Larval development (i.e., growth and survival) of the Pacific oyster (Crassostrea gigas) was not changed when fed a mixture of microalgae grown in NAC- and F127-supplemented culture medium. Based upon these results, we propose that culture media enrichment with NAC and pluronic F127 is an effective and easily adopted approach to increase algal productivity and enhance the nutritional quality of marine microalgal strains commonly cultured for live-feed applications in aquaculture.

Key points

• Single and combined NAC and pluronic F127 culture media supplementation significantly enhanced the productivity of Chaetoceros calcitrans and Chaetoceros muelleri cultures.

• Culture media enrichments with NAC and F127 can increase omega-3-fatty acid content of algal biomass.

• Microalgae grown in NAC- and pluronic F127-supplemented culture media are suitable for live-feed applications.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00253-021-11147-8.

Pediococcus pentosaceus ZJUAF-4 relieves oxidative stress and restores the gut microbiota in diquat-induced intestinal injury

Lactic acid bacteria (LAB) play a key role in promoting health and preventing diseases because of their beneficial effects, such as antimicrobial activities, modulating immune responses, maintaining the gut epithelial barrier and antioxidant capacity. However, the mechanisms with which LAB relieve oxidative stress and intestinal injury induced by diquat in vivo are poorly understood. In the present study, Pediococcus pentosaceus ZJUAF-4 (LAB, ZJUAF-4), a selected probiotics strain with strong antioxidant capacities, was appointed to evaluate the efficiency against oxidative stress in diquat-induced intestinal injury of mice. Alanine transaminase (ALT) and aspartate aminotransferase (AST) were analyzed to estimate the liver injury. The intestinal permeability was evaluated by 4 kDa fluorescein isothiocyanate (FITC)-dextran (FD4), D-lactate (DLA), and diamine oxidase (DAO) levels. Jejunum reactive oxygen species (ROS) production was examined by dihydroethidium (DHE) staining. Western blotting was used to detect the expression of nuclear factor (erythroid-derived-2)-like 2 (Nrf2) and its downstream genes in jejunum. The gut microbiota was analyzed by high-throughput sequencing method based on the 16S rRNA genes. The results showed that ZJUAF-4 pretreatment was found to protect the intestinal barrier function and maintain intestinal redox homeostasis under diquat stimulation. Moreover, oral administration of ZJUAF-4 increased the expression of Nrf2 and its downstream genes. High-throughput sequencing analysis indicated that ZJUAF-4 contributed to restoring the gut microbiota influenced by diquat. Our results suggested that ZJUAF-4 protected the intestinal barrier from oxidative stress-induced damage by modulating the Nrf2 pathway and gut microbiota, indicating that ZJUAF-4 may have potential applications in preventing and treating oxidative stress-related intestinal diseases. KEY POINTS: • ZJUAF-4 exerted protective effects against diquat-induced intestinal injury. • Activation of Nrf2 and its downstream targets towards oxidative stress. • ZJUAF-4 administration restoring gut microbiota.

Protection of Polyphenols against Glyco-Oxidative Stress: Involvement of Glyoxalase Pathway

Chronic high glucose (HG) exposure increases methylglyoxal (MGO)-derived advanced glycation end-products (AGEs) and is involved in the onset of pathological conditions, such as diabetes, atherosclerosis and chronic-degenerative diseases. Under physiologic conditions the harmful effects of MGO are contrasted by glyoxalase system that is implicated in the detoxification of Reactive Carbonyl Species (RCS) and maintain the homeostasis of the redox environment of the cell. Polyphenols are the most abundant antioxidants in the diet and present various health benefits. Aims of the study were to investigate the effects of HG-chronic exposure on glyco-oxidation and glyoxalase system in intestinal cells, using CaCo-2 cells. Moreover, we studied the effect of apple polyphenols on glyco-oxidative stress. Our data demonstrated that HG-treatment triggers glyco-oxidation stress with a significant increase in intracellular Reactive Oxygen Species (ROS), lipid peroxidation, AGEs, and increase of Glyoxalase I (GlxI) activity. On the contrary, Glyoxalase II (GlxII) activity was lower in HG-treated cells. We demonstrate that apple polyphenols exert a protective effect against oxidative stress and dicarbonyl stress. The increase of total antioxidant capacity and glutathione (GSH) levels in HG-treated cells in the presence of apple polyphenols was associated with a decrease of GlxI activity.

From waste to health: sustainable exploitation of grape pomace seed extract to manufacture antioxidant, regenerative and prebiotic nanovesicles within circular economy

Pomace seed extract loaded vesicles were prepared as promising technological and green solution to exploit agri-food wastes and by-products, and develop high value-added products for human health. An antioxidant extract rich in bioactive compounds (epicatechins, catechin, gallic acid, quercetin and procynidins) was obtained from the seeds isolated from the pomace of Cannonau red grape cultivar. The extract was incorporated into phospholipid vesicles ad hoc formulated for intestinal delivery, by combining them, for the first time, whit a maltodextrin (Glucidex). Glucidex-transfersomes, glucidex-hyalurosomes and glucidex-hyalutransferomes were prepared, characterized and tested. Glucidex-liposomes were used as reference. All vesicles were small in size (~ 150 nm), homogeneously dispersed and negatively charged. Glucidex-transfersomes and especially glucidex-hyalutransfersomes disclosed an unexpected resistance to acidic pH and high ionic strength, as they maintained their physico-chemical properties (size and size distribution) after dilution at pH 1.2 simulating the harsh gastric conditions. Vesicles were highly biocompatible and able to counteract the oxidative damages induced in Caco-2 cells by using hydrogen peroxide. Moreover, they promoted the formation of Lactobacillus reuteri biofilm acting as prebiotic formulation. Overall results suggest the potential of glucidex-hyalutransfersomes as food supplements for the treatment of intestinal disorders.

Structural features of pectic polysaccharides from stems of two species of Radix Codonopsis and their antioxidant activities

In this study, two pectic polysaccharides from stems of Codonopsis pilosula (CPSP-1) and C. tangshen (CTSP-1) were obtained by ion exchange chromatography and gel filtration. The molecular weight of CPSP-1 and CTSP-1 were 13.1 and 23.0 kDa, respectively. The results of structure elucidation indicated that both CPSP-1 and CTSP-1 are pectic polysaccharides with long homogalacturonan regions (HG) (some of galacturonic acid units were methyl esterified) and rhamnogalacturonan I (RG-I) regions. Side chains for CTSP-1 are both arabinogalactan type I (AG-I) and type II (AG-II), while CPSP-1 only has AG-II. The biological test demonstrated that CPSP-1 and CTSP-1 displayed an antioxidant property through mediating the intestinal cellular antioxidant defense system, which could protect cultured intestinal cells from oxidative stress induced oxidative damages and cell viability suppression. CPSP-1 and CTSP-I showed different bioactivities and mechanisms, which may be due to the difference in their structures.

Anti-Inflammatory and Cytoprotective Effect of Plant Sterol and Galactooligosaccharides-Enriched Beverages in Caco-2 Cells

Plant sterol (PS) (1 g/100 mL) enriched milk-based fruit beverages with or without galactooligosaccharides (GOS) (1.8 g/100 mL) were used in differentiated Caco-2 cells. Their potential cytopreventive effect against oxidative stress induced by cholesterol oxidation products (COPs) and their anti-inflammatory properties were evaluated. Preincubation (24 h) with bioaccessible fractions from beverages without and with GOS (MfB and MfB-G) completely prevented the COPs (60 μM/4 h) induced oxidative stress independent to GOS presence with exception to calcium influx and GSH content, where a partial protective effect was observed. Besides, MfB produced a significant (p < 0.05) reduction of IL-8 (40%) and IL-6 (50%) after IL-1β-induction (1 ng/mL/24 h) through the inhibition of NF-κB p65 translocation into the nucleus (16%) compared to control cells, while GOS presence compromised their anti-inflammatory effect. Therefore, PS-enriched milk-based fruit beverage could be an interesting strategy to prevent intestinal injury produced by COPs and to attenuate the pro-inflammatory process in intestinal human diseases. GOS addition had no extra beneficial antioxidant effect and even reduced their anti-inflammatory properties.

Rice-derived peptide AAGALPS inhibits TNF-α-induced inflammation and oxidative stress in vascular endothelial cells

Injury of vascular endothelial cell is one of the main factors triggering atherosclerosis. Peptide AAGALPS was derived from digestion and absorption product of rice α-globulin, which was proved to prevent atherosclerosis in previous study. This study aims to investigate the potential effects of AAGALPS on improving tumor necrosis factor-α (TNF-α)-stimulated human umbilical vein endothelial cells' (HUVECs) injury. As a result, the viability of HUVECs stimulated by tumor necrosis factor-α was significantly increased by AAGALPS in a dose-dependent manner until 25 μg/ml. The peptide obviously reduced the levels of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, nitric oxide, inducible nitric oxide synthase, reactive oxygen species, and malondialdehyde and increased the concentrations of glutathione peroxidase. Furthermore, AAGALPS inhibited the nuclear factor κB (NF-κB) activation and nuclear translocation through regulating inhibitor of nuclear factor κB kinase α and inhibitor of NF-κB. These results indicated that AAGALPS protected vascular endothelial cells through mediating inflammation and oxidative stress.

Effect of High Glucose-Induced Oxidative Stress on Paraoxonase 2 Expression and Activity in Caco-2 Cells

(1) Background: Hyperglycemia leads to several biochemical and physiological consequences, such as the generation of advanced glycation end products (AGEs) and reactive oxygen species (ROS), which are involved in the development of several human diseases. Intestinal cells are continuously exposed to pro-oxidants and lipid peroxidation products from ingested foods, and also to glyco-oxidative damage. It has been reported that free radical generation may be linked to the development of inflammation-related gastrointestinal diseases. (2) Methods: The effects of high glucose (HG) treatment (50 mM) were assessed in terms of free radical production, lipid peroxidation, and AGEs formation. Furthermore, the expression and the antiapoptotic and antioxidant activity of the paraoxonase-2 (PON2) enzyme in intestinal cells has been investigated. (3) Results: Caco-2 cells treated with media supplied with high glucose (HG) (50 mM) showed, with respect to physiological glucose concentration (25 mM), an increase in ROS production, lipid peroxidation, and AGEs formation. Moreover, a lower PON2 expression and activity in HG-treated cells was related to activation of the apoptotic pathways. (4) Conclusions: Our results demonstrated that high glucose concentrations triggered glyco-oxidative stress in intestinal cells; the downregulation of PON2 could result in a higher oxidative stress and might contribute to intestinal dysfunction.

Protective Effects of Fucoidan against Hydrogen Peroxide-Induced Oxidative Damage in Porcine Intestinal Epithelial Cells

Simple Summary

High levels of production in intensive farming systems make domestic animals like piglets particularly susceptible to oxidative stress, which is detrimental to intestinal homeostasis and function. It is of paramount importance to identify effective and reliable nutrients to counteract oxidative damage to the porcine intestinal epithelium, especially with the recent phasing out of the use of antibiotics in China. This study indicates that fucoidan could ameliorate hydrogen peroxide-induced oxidative stress in porcine intestinal epithelial cells, primarily owing to the action of fucoidan to facilitate nuclear factor-erythroid 2-related factor-2 signals and cellular antioxidant responses. These findings may provide useful implications for practical swine production.

Abstract

This study was conducted to evaluate the effectiveness of fucoidan in ameliorating hydrogen peroxide (H₂O₂)-induced oxidative stress to porcine intestinal epithelial cell line (IPEC-1). The cell viability test was initially performed to screen out appropriate concentrations of H₂O₂ and fucoidan. After that, cells were exposed to H₂O₂ in the presence or absence of pre-incubation with fucoidan. Hydrogen peroxide increased the apoptotic and necrotic rate, boosted reactive oxygen species (ROS) generation, and disturbed the transcriptional expression of genes associated with antioxidant defense and apoptosis in IPEC-1 cells. Pre-incubation with fucoidan inhibited the increases in necrosis and ROS accumulation induced by H₂O₂. Consistently, in the H₂O₂-treated IPEC-1 cells, fucoidan normalized the content of reduced glutathione as well as the mRNA abundance of NAD(P)H quinone dehydrogenase 1 and superoxide dismutase 1 while it prevented the overproduction of malondialdehyde. Moreover, H₂O₂ stimulated the translocation of nuclear factor-erythroid 2-related factor-2 to the nucleus of IPEC-1 cells, but this increase was further promoted by fucoidan pre-treatment. The results suggest that fucoidan is effective in protecting IPEC-1 cells against oxidative damage induced by H₂O₂, which may help in developing appropriate strategies for maintaining the intestinal health of young piglets.

Effects of Creatine Treatment on Jejunal Phenotypes in a Rat Model of Acidosis

We investigated the effects of creatine treatment on jejunal phenotypes in a rat model of oxidative stress induced by acidosis. In particular, the activities of some antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, and glutathione reductase), the level of lipid peroxidation, the expression of heat shock proteins (HSP70), and the expression of the major carriers of the cells (Na⁺/K⁺-ATPase, sodium-glucose Transporter 1—SGLT1, and glucose transporter 2—GLUT2) were measured under control and chronic acidosis conditions. Creatine did not affect the activity of antioxidant enzymes in either the control or acidosis groups, except for catalase, for which the activity was reduced in both conditions. Creatine did not change the lipid peroxidation level or HSP70 expression. Finally, creatine stimulated (Na⁺/K⁺)-ATPase expression under both control and chronic acidosis conditions. Chronic acidosis caused reductions in the expression levels of GLUT2 and SGLT1. GLUT2 reduction was abolished by creatine, while the presence of creatine did not induce any strengthening effect on the expression of SGLT1 in either the control or chronic acidosis groups. These results indicate that creatine has antioxidant properties that are realized through direct interaction of the molecule with reactive oxygen species. Moreover, the administration of creatine seems to determine a functional strengthening of the tissue, making it more resistant to acidosis.

Selenium-enriched Bacillus paralicheniformis SR14 attenuates H2O2-induced oxidative damage in porcine jejunum epithelial cells via the MAPK pathway

Oxidative stress plays a detrimental role in gastrointestinal disorders. Although selenium-enriched probiotics have been shown to strengthen oxidation resistance and innate immunity, the potential mechanism remains unclear. Here, we focused on the biological function of our material, selenium-enriched Bacillus paralicheniformis SR14 (Se-BP), and investigated the antioxidative effects of Se-BP and its underlying molecular mechanism in porcine jejunum epithelial cells. First, we prepared Se-BP and quantified for its selenium and bacterial contents. Then, in vitro free radical scavenging activity was measured to evaluate the potential antioxidant effect of Se-BP. Third, to induce an appropriate oxidative stress model, we adopted different concentrations of H₂O₂ and determined the most suitable concentration by a methyl thiazolyl tetrazolium (MTT) assay. Regarding treatment with Se-BP and H₂O₂, we found that Se-BP increased cell viability and prevented lactate dehydrogenase release when administered prior to H₂O₂ exposure. Additionally, Se-BP markedly suppressed reactive oxygen species and malondialdehyde production in cells and effectively attenuated apoptosis. Compared with incubation with H₂O₂ alone, treatment with Se-BP significantly promoted phosphorylation of ERK and p38 MAPK signaling molecules. When administered with ERK and p38 MAPK inhibitors, Se-BP did not alleviate the decrease in cell viability. Our results suggest that Se-BP prevents H₂O₂-induced cell damage by activating the ERK/p38 MAPK signaling pathways.

Hyperuricemia and gout are associated with cancer incidence and mortality: A meta-analysis based on cohort studies

The association between hyperuricemia or gout and cancer risk has been investigated in various published studies, but their results are conflicting. We conducted a meta-analysis to investigate whether hyperuricemia or gout was associated with the cancer incidence and mortality. Linear and nonlinear trend analyses were conducted to explore the dose-response association between them. The pooled relative risk (RR) and 95% confidence interval (CI) were used to evaluate cancer risk. A total of 24 articles (33 independent studies) were eligible for inclusion. When compared participants with the highest SUA (hyperuricemia) levels and those with the lowest SUA levels, the pooled RR was 1.08 (95% CI, 1.04-1.12), it was significantly associated among males but not among females (males, RR = 1.07; 95% CI, 1.03-1.11; females, RR = 1.06; 95% CI, 0.96-1.17). Hyperuricemia increased total cancer mortality (RR = 1.15; 95% CI, 1.05-1.26), but a significant association was observed in females rather than in males (females: RR = 1.26; 95% CI, 1.09-1.45; males, RR = 1.02; 95% CI, 0.80-1.30). Linear relationships of SUA levels with overall cancer incidence (p for nonlinearity = 0.238) and overall cancer mortality (p for nonlinearity = 0.263) were identified. However, 1 mg/dL increment in SUA levels was weakly significant in overall cancer incidence (RR = 1.01; 95% CI, 1.01-1.01) but not associated with overall cancer mortality (RR = 1.01; 95% CI, 0.99-1.03). Gout was significantly associated with increased cancer incidence (RR = 1.19; 95% CI, 1.12-1.25). In conclusion, Hyperuricemia or gout was associated with higher cancer incidence and mortality. Though a potential linear relationship between them was found, we'd better treat this result with caution.

Beneficial effects of water-soluble chestnut (Castanea sativa Mill.) tannin extract on chicken small intestinal epithelial cell culture

Feed and water supplementation with powdered hydrolyzable tannins from chestnut represents a valuable alternative strategy to antibiotics in animal nutrition. In this study, we evaluated the effects and safety of a water-soluble form of chestnut tannin (WST) in an in vitro model of chicken small intestinal epithelial cells (CSIEC). A chicken cell culture was established, and WST in concentrations of 0.025, 0.05, 0.1, and 0.2% were tested for cytotoxicity, cell proliferation, metabolic activity, production of reactive oxygen species, intracellular antioxidative potential, genotoxicity, and influence on the epithelia cell cycle. The tested concentrations showed a significant (P < 0.05) greater proliferative effect on CSIEC than the control medium (maximal proliferation at 0.1% WST as determined by optical density measurements). The 0.2% concentration of WST was cytotoxic, causing significantly higher (P < 0.05) nitric oxide and hydrogen peroxide production but with no short-term genotoxicity. Although increasing the concentration caused a decline in the metabolism of challenged cells (the lowest at 0.1% WST), metabolic activity remained higher than that in control cells. The antioxidant potential was 75% better and significantly (P < 0.05) higher in the 0.1% WST cultured cells compared to control. In conclusion, the cultured CSIEC are useful tools in basic and clinical research for the study of intestinal physiology, as they retain physiological and biochemical properties and epithelial morphology close to the original tissue and, in many ways, reflect the in vivo state. Our results indicate that WST exert a beneficial effect on intestinal epithelia, since they: i) stimulate proliferation of enterocytes; ii) increase antioxidative potential; iii) have no genotoxic effect; and iv) do not affect cellular metabolism. Our results reinforce the importance of WST as promising candidates for further evaluation and use in commercial broiler farm production.

Biogenic Polyphosphate Nanoparticles from Synechococcus sp. PCC 7002 Exhibit Intestinal Protective Potential in Human Intestinal Epithelial Cells In Vitro and Murine Small Intestine Ex Vivo

Polyphosphates are one of the active compounds from probiotics to maintain gut health. The current research extracted and purified intact biogenic polyphosphate nanoparticles (BPNPs) from Synechococcus sp. PCC 7002 cells. BPNPs were near-spherical anionic particles (56.9 ± 15.1 nm) mainly composed of calcium and magnesium salt of polyphosphate and were colloidally stable at near-neutral and alkaline pH. BPNPs survived gastrointestinal digestion in mice and could be absorbed and transported by polarized Caco-2 cell monolayers. They dose-dependently increased the tightness of intercellular tight junction and the expression of claudin-4, occludin, zonula occludens-1, and heat shock protein 27 in Caco-2 cell monolayers. BPNPs also effectively attenuated H₂O₂-induced cell death, plasma membrane impairment, and intracellular superoxide production in NCM460 cells. In addition, they conferred resistance to H₂O₂-induced barrier disruption in freshly excised mouse small intestine. Our results suggest that BPNPs are a promising postbiotic nanomaterial with potential applications in gut health maintenance.

Comparative estimation of sulfiredoxin levels between chronic periodontitis and healthy patients - A case-control study

BACKGROUND

Growing evidence suggests that oxidative stress forms a key component in the etiopathogenesis of periodontitis. Studies have shown potential antioxidants responsible for combating the pro-oxidants which stress the periodontium. But, peroxiredoxin-sulfiredoxin system is the least explored in periodontal disease.

METHODS

A case-control study was conducted on 30 participants who fulfilled the inclusion criteria from the Department of Periodontics, Saveetha Dental College and Hospital, Chennai, India. The patients were divided into two groups: 1) Group A- healthy controls (n = 18), 2) Group B- patients with generalized chronic periodontitis (n = 17). Following clinical examination, gingival tissue samples were procured from both the groups and subjected to protein quantification by Lowry method. The samples with adequate protein concentration (n = 30) from the two groups were further analyzed by enzyme-linked immunosorbent assay for estimation of sulfiredoxin levels.

RESULTS

Sulfiredoxin levels were significantly higher in the gingival tissues of chronic periodontitis patients (171.20 ± 16.97 ng/mL) than in healthy controls (131.20 ± 22.87) with P < 0.001. Also, the levels of sulfiredoxin in gingival tissue of periodontitis patients positively correlated with site-specific probing depth (r = 0.67; P = 0.007) and clinical attachment level (r = 0.55; P = 0.035).

CONCLUSIONS

The present study was a novel attempt to estimate the levels of sulfiredoxin which was significantly elevated in the diseased sites of patients with chronic periodontitis. Future studies are required to probe the role of sulfiredoxin in the etiopathogenesis of periodontal disease.

Subtropical hibernation in juvenile tegu lizards (Salvator merianae): insights from intestine redox dynamics

Juvenile tegu lizards (Salvator merianae) experience gradual and mild temperature changes from autumn to winter in their habitat. This tropical/subtropical reptile enter a state of dormancy, with an 80% reduction in metabolic rate, that remains almost constant during winter. The redox metabolism in non-mammalian vertebrates that hibernate under such distinguished conditions is poorly understood. We analyzed the redox metabolism in the intestine of juvenile tegus during different stages of their first annual cycle. The effect of food deprivation (in spring) was also studied to compare with fasting during hibernation. Both winter dormancy and food deprivation caused decreases in reduced glutathione levels and glutathione transferase activity. While glutathione peroxidase and glutathione transferase activities decreased during winter dormancy, as well as glutathione (GSH) levels, other antioxidant enzymes (catalase, superoxide dismutase and glutathione reductase) remained unchanged. Notably, levels of disulfide glutathione (GSSG) were 2.1-fold higher in late autumn, when animals were in the process of depressing metabolism towards hibernation. This increased “oxidative tonus” could be due to a disruption in NADPH-dependent antioxidant systems. In dormancy, GSSG and lipid hydroperoxides were diminished by 60–70%. The results suggest that the entrance into hibernation is the main challenge for the redox homeostasis in the intestine of juvenile tegus.

Two complement fixing pectic polysaccharides from pedicel of Lycium barbarum L. promote cellular antioxidant defense

Purification, characterization and biological activities of polysaccharides from Lycium barbarum pedicel were investigated in this study. Two polysaccharides, PLBP-I-I and PLBP-II-I, were obtained from water extracts by anion exchange chromatography and gel filtration. Structural elucidation based on IR, ¹H NMR, and ¹³C NMR spectra indicated that these two fractions were typical pectic polysaccharides, with homogalacturonan and rhamnogalacturonan type I regions and arabinogalactan side chains, and some of the galacturonic acid units were methyl esterified. Both fractions exhibited potent complement fixating activity and pro-antioxidant defense capacity, and those two fractions showed different activities. The higher complement fixation activity was obtained in fraction PLBP-I-I, while the higher pro-antioxidant defense capacity was obtained in fraction PLBP-II-I, which may be due to the structural differences between those two fractions. Thus, the pedicel of L. barbarum could be used as a potential source for natural immunomodulator and antioxidant.

Inflammatory and Oxidative Responses Induced by Exposure to Commonly Used e-Cigarette Flavoring Chemicals and Flavored e-Liquids without Nicotine

Background: The respiratory health effects of inhalation exposure to e-cigarette flavoring chemicals are not well understood. We focused our study on the immuno-toxicological and the oxidative stress effects by these e-cigarette flavoring chemicals on two types of human monocytic cell lines, Mono Mac 6 (MM6) and U937. The potential to cause oxidative stress by these flavoring chemicals was assessed by measuring the production of reactive oxygen species (ROS). We hypothesized that the flavoring chemicals used in e-juices/e-liquids induce an inflammatory response, cellular toxicity, and ROS production.

Methods: Two monocytic cell types, MM6 and U937 were exposed to commonly used e-cigarette flavoring chemicals; diacetyl, cinnamaldehyde, acetoin, pentanedione, o-vanillin, maltol and coumarin at different doses between 10 and 1,000 μM. Cell viability and the concentrations of the secreted inflammatory cytokine interleukin 8 (IL-8) were measured in the conditioned media. Cell-free ROS produced by these commonly used flavoring chemicals were also measured using a 2′,7′dichlorofluorescein diacetate probe. These DCF fluorescence data were expressed as hydrogen peroxide (H₂O₂) equivalents. Cytotoxicity due to the exposure to selected e-liquids was assessed by cell viability and the IL-8 inflammatory cytokine response in the conditioned media.

Results: Treatment of the cells with flavoring chemicals and flavored e-liquid without nicotine caused cytotoxicity dose-dependently. The exposed monocytic cells secreted interleukin 8 (IL-8) chemokine in a dose-dependent manner compared to the unexposed cell groups depicting a biologically significant inflammatory response. The measurement of cell-free ROS by the flavoring chemicals and e-liquids showed significantly increased levels of H₂O₂ equivalents in a dose-dependent manner compared to the control reagents. Mixing a variety of flavors resulted in greater cytotoxicity and cell-free ROS levels compared to the treatments with individual flavors, suggesting that mixing of multiple flavors of e-liquids are more harmful to the users.

Conclusions: Our data suggest that the flavorings used in e-juices can trigger an inflammatory response in monocytes, mediated by ROS production, providing insights into potential pulmonary toxicity and tissue damage in e-cigarette users.

A Pectic Polysaccharide from Sijunzi Decoction Promotes the Antioxidant Defenses of SW480 Cells

Sijunzi Decoction (SJZD) is a formula used for the treatment of spleen deficiency and gastrointestinal diseases in Traditional Chinese Medicine. Polysaccharides are reported to be the main components of SJZD responsible for its bio-functions. However, highly purified and clearly characterized polysaccharides from SJZD are not well described. Here we obtained a purified polysaccharide (SJZDP-II-I) from SJZD using ion exchange chromatography and gel filtration. Structure analysis by FT-IR and NMR identified SJZDP-II-I as a typical pectic polysaccharide with homogalacturonan and rhamnogalacturonan type I regions and arabinogalactan type I and II as side chains. In vitro studies indicated that SJZDP-II-I treatment could significantly enhance the total antioxidant capacity of SW480 cells, resulting from the promoted expressions of antioxidant enzymes and their master regulator PGC-1α, which would be valuable for further research and applications.

Effects of astaxanthin in mice acutely infected with Trypanosoma cruzi

During Trypanosoma cruzi infection, oxidative stress is considered a contributing factor for dilated cardiomyopathy development. In this study, the effects of astaxanthin (ASTX) were evaluated as an alternative drug treatment for Chagas disease in a mouse model during the acute infection phase, given its anti-inflammatory, immunomodulating, and anti-oxidative properties. ASTX was tested in vitro in parasites grown axenically and in co-culture with Vero cells. In vivo tests were performed in BALB/c mice (4-6 weeks old) infected with Trypanosoma cruzi and supplemented with ASTX (10 mg/kg/day) and/or nifurtimox (NFMX; 100 mg/kg/day). Results show that ASTX has some detrimental effects on axenically cultured parasites, but not when cultured with mammalian cell monolayers. In vivo, ASTX did not have any therapeutic value against acute Trypanosoma cruzi infection, used either alone or in combination with NFMX. Infected animals treated with NFMX or ASTX/NFMX survived the experimental period (60 days), while infected animals treated only with ASTX died before day 30 post-infection. ASTX did not show any effect on the control of parasitemia; however, it was associated with an increment in focal heart lymphoplasmacytic infiltration, a reduced number of amastigote nests in cardiac tissue, and less hyperplasic spleen follicles when compared to control groups. Unexpectedly, ASTX showed a negative effect in infected animals co-treated with NFMX. An increment in parasitemia duration was observed, possibly due to ASTX blocking of free radicals, an anti-parasitic mechanism of NFMX. In conclusion, astaxanthin is not recommended during the acute phase of Chagas disease, either alone or in combination with nifurtimox.

Biogenic Nanoselenium Particles Effectively Attenuate Oxidative Stress-Induced Intestinal Epithelial Barrier Injury by Activating the Nrf2 Antioxidant Pathway

In the present study, a new form of selenium nanoparticle (biogenic nanoselenium (BNS) particles) was synthesized using bacteria. The protection of BNS particles against oxidative stress-induced intestinal barrier dysfunction and the inherent mechanisms of this process were investigated, and selenomethionine (SeMet) and chemically synthesized nanoselenium (Nano-Se) particles were used for comparison. Characterization of BNS particles revealed that they were monodispersed and homogeneous spheres, with an average size of 139.43 ± 7.44 nm. In the mouse model of intestinal oxidative stress, BNS particles were found to protect the mouse intestinal barrier function and preserve intestinal redox homeostasis more efficiently than SeMet and Nano-Se. In vitro experiments with porcine jejunum epithelial (IPEC-J2) cells verified the stronger epithelial barrier-protecting effect of BNS particles against oxidative stress, with reduced cell apoptosis and an improved cell redox state. BNS activated the nuclear factor (erythroid-derived-2)-like 2 (Nrf2) and increased the expression of its downstream genes, including thioredoxin reductase (TXNRD)-1, NADPH dehydrogenase (NQO)-1, heme oxygenase (HO)-1, and thioredoxin (Trx), in dose- and time-dependent manners. In contrast, SeMet and Nano-Se merely enhanced the activity of the selenoenzymes TXNRD-1 and glutathione peroxidase (GPx)-1, indicating the role of selenium donors. Moreover, the knock down of Nrf2 significantly blocked the antioxidative effect of BNS, confirming that BNS protects the intestinal barrier from oxidative stress-induced damage by activating Nrf2 and its downstream genes. Our results suggest that BNS is a promising selenium species with potential application in treating oxidative stress-related intestinal diseases.

Anti-Cancer Effects of Green Tea by Either Anti- or Pro- Oxidative Mechanisms

Tea derived from the leaves and buds of Camellia sinensis (Theaceae) is consumed worldwide. Green tea contains various components with specific health-promoting effects, and is believed to exert protective effects against diseases including cancer, diabetes and hepatitis, as well as obesity. Of the various tea components, the polyphenol catechins have been the subject of extensive investigation and among the catechins, (-)-epigallocatechin gallate has the strongest bioactivity in most cases. Our research group has postulated that hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α are targets of green tea constituents including (-)-epigallocatechin gallate for their anti-diabetes, anti-obesity, and anti-hepatitis effects, respectively. Published papers were reviewed to determine whether the observed changes in these factors can be correlated with anti-cancer effects of green tea. Two major action mechanisms of (-)-epigallocatechin gallate have been proposed; one associated with its anti-oxidative properties and the other with its pro-oxidative activity. When reactive oxygen species are assumed to be involved, our findings that (-)-epigallocatechin gallate down- regulated hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α may explain the anti-cancer effect of green tea as well. However, further studies are required to elucidate which determinant directs (-)-epigallocatechin gallate action as an anti-oxidant or a pro-oxidant for favorable activity.

Health Risks of Food Oxidation

The impact of dietary habits on our health is indisputable. Consumer's concern on aging and age-related diseases challenges scientists to underline the potential role of food on the extension and guarantee of lifespan and healthspan. While some dietary components and habits are generally regarded as beneficial for our health, some others are being found to exert potential toxic effects and hence, contribute to the onset of particular health disorders. Among the latter, lipid and protein oxidation products formed during food production, storage, processing, and culinary preparation have been recently identified as potentially harmful to humans. Upon intake, food components are further degraded and oxidized during the subsequent digestion phases and the pool of compounds formed in the lumen is in close contact with the lamina propria of the intestines. Some of these oxidation products have been found to promote inflammatory conditions in the gut (i.e., bowel diseases) and are also reasonably linked to the onset of carcinogenic processes. Upon intestinal uptake, some species are distributed by the bloodstream causing an increase in oxidative stress markers and impairment of certain physiological processes through alteration of specific gene expression pathways. This chapter summarizes the most recent discoveries on this topic with particular stress on challenges that we face in the near future: understanding the molecular basis of disease, the suitability of using living animals vs in vitro model systems and the necessity of using massive genomic techniques and versatile mass spectrometric technology.

Peptide GEQQQQPGM derived from rice α-globulin reduces the risk of atherosclerosis in hamsters by improving vascular endothelial cells injury

The amino acid sequence of the peptide, GEQQQQPGM was determined by LC-mass spectrometry (MS)/MS.

Blue Light Differentially Modulates Cell Survival and Growth

Previous studies have reported that blue light (400–500 nm) inhibits cell mitochondrial activity. We investigated the hypothesis that cells with high energy consumption are most susceptible to blue-light-induced mitochondrial inhibition. We estimated cell energy consumption by population doubling time, and cell survival and growth by succinate dehydrogenase (SDH) activity. Six cell types were exposed to 5 or 60 J/cm2 of blue light from quartz-tungsten-halogen (QTH), plasma-arc (PAC), or argon laser sources in monolayer culture. Post-light SDH activity correlated positively with population doubling time (R2 = 0.91 for PAC, 0.76 for QTH, 0.68 for laser); SDH activity increased for cell types with the longest doubling times and was suppressed for cell types with shorter doubling times. Thus, light-induced exposure differentially affects SDH activity, cell survival, and growth, depending on cell energy consumption. Blue light may be useful as a therapeutic modulator of cell growth and survival.

Effects of soybean isoflavone on intestinal antioxidant capacity and cytokines in young piglets fed oxidized fish oil

To investigate the effect of glycitein, a synthetic soybean isoflavone (ISF), on the intestinal antioxidant capacity, morphology, and cytokine content in young piglets fed oxidized fish oil, 72 4-d-old male piglets were assigned to three treatments. The control group was fed a basal diet containing fresh fish oil, and the other two groups received the same diet except for the substitution with the same dosage of oxidized fish oil alone or with ISF (oxidized fish oil plus ISF). After 21 d of feeding, supplementation of oxidized fish oil increased the levels of malondialdehyde (MDA), oxidized glutathione (GSSG), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), nuclear factor κ B (NF-κB), inducible nitric oxide synthase (iNOS), NO, and Caspase-3 in jejunal mucosa, and decreased the villous height in duodenum and the levels of secretory immunoglobulin A (sIgA) and IL-4 in the jejunal mucosa compared with supplementation with fresh oil. The addition of oxidized fish oil plus ISF partially alleviated this negative effect. The addition of oxidized fish oil plus ISF increased the villous height and levels of sIgA and IL-4 in jejunal mucosa, but decreased the levels of IL-1β and IL-2 in jejunal mucosa (P<0.05) compared with oxidized fish oil. Collectively, these results show that dietary supplementation of ISF could partly alleviate the negative effect of oxidized fish oil by improving the intestinal morphology as well as the antioxidant capacity and immune function in young piglets.

In Vitro Investigation of Six Antioxidants for Pig Diets

Oxidative stress in the small intestinal epithelium can lead to barrier malfunction. In this study, the effect of rosmarinic acid (RA), quercetin (Que), gallic acid (GA), lipoic acid (LA), ethoxyquin (ETQ) and Se-methionine (SeMet) pre-treatments using 2 mM Trolox as a control on the viability and the generation of intracellular reactive oxygen species (iROS) of oxidatively (H₂O₂) stressed intestinal porcine epithelial cells (IPEC-J2) was investigated. A neutral red assay showed that RA (50-400 µM), Que (12.5-200 µM), GA (50-400 µM), ETQ (6.25-100 µM), and SeMet (125-1000 µM) pre-treatments but not LA significantly increased the viability of H₂O₂-stressed IPEC-J2 cells (p < 0.05). A 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H₂DCFDA) fluorescent probe showed that RA (100-600 µM), Que (25-800 µM), ETQ (3.125-100 µM) and SeMet (500-2000 µM) pre-treatments significantly reduced iROS in IPEC-J2 monolayers (p < 0.05). Moreover, RA and Que were most effective in reducing iROS. Therefore, the effects of RA and Que on barrier functioning in vitro were examined. RA and Que pre-treatments significantly decreased fluorescein isothiocyanate (FITC)-conjugated dextran-4 (4 kDa) permeability and transepithelial electrical resistance (TEER) of an IPEC-J2 cell monolayer (p < 0.05). These in vitro results of RA and Que hold promise for their use as antioxidants in pig feed.

Tuning the inflammatory response to silver nanoparticles via quercetin in Caco-2 (co-)cultures as model of the human intestinal mucosa

Interaction of nanoparticles with food matrix components may cause unpredictable health complications. Using an improved Caco-2 cell-based in vitro (co-)culture model the potential of quercetin as one of the major food flavonoids to alter the effect of silver nanoparticles (Ag-NPs) <20 nm in the human intestinal mucosa at real life concentrations was investigated. Ag-NPs (15-90 μg/ml) decreased cell viability and reduced thiol groups, induced oxidative/nitrosative stress and lipid peroxidation and led to activity changes of various antioxidant enzymes after 3h exposure. The contribution of Ag(+) ions within the concentrations released from nanoparticles was shown to be less important, compared to Ag-NPs. While leading to inflammatory response in the intestines, Ag-NPs, paradoxically, also showed a potential anti-infammatory effect manifested in down-regulated IL-8 levels. Quercetin, co-administered with Ag-NPs, led to a reduction of cytotoxicity, oxidative stress, and recovered metabolic activity of Caco-2 cells, suggesting the protective effects of this flavonoid against the harmful effect of Ag-NPs. Quercetin not only alleviated the effect of Ag-NPs on the gastrointestinal cells, but also demonstrated a potential to serve as a tool for reversible modulation of intestinal permeability.

Integrative Physiology of Fasting

Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting.

Aldo-keto reductase 1B10 protects human colon cells from DNA damage induced by electrophilic carbonyl compounds

Electrophilic carbonyl compounds are highly cytotoxic and genotoxic. Aldo-keto reductase 1B10 (AKR1B10) is an enzyme catalyzing reduction of carbonyl compounds to less toxic alcoholic forms. This study presents novel evidence that AKR1B10 protects colon cells from DNA damage induced by electrophilic carbonyl compounds. AKR1B10 is specifically expressed in epithelial cells of the human colon, but this study found that AKR1B10 expression was lost or markedly diminished in colorectal cancer, precancerous tissues, and a notable portion of normal adjacent tissues (NAT). SiRNA-mediated silencing of AKR1B10 in colon cancer cells HCT-8 enhanced cytotoxicity of acrolein and HNE, whereas ectopic expression of AKR1B10 in colon cancer cells RKO prevented the host cells against carbonyl cytotoxicity. Furthermore, siRNA-mediated AKR1B10 silencing led to DNA breaks and activation of γ-H2AX protein, a marker of DNA double strand breaks, particularly in the exposure of HNE (10 μM). In the AKR1B10 silenced HCT-8 cells, hypoxanthine-guanine phosphoribosyl transferase (HPRT) mutant frequency increased by 26.8 times at basal level and by 33.5 times in the presence of 10 μM HNE when compared to vector control cells. In these cells, the cyclic acrolein-deoxyguanosine adducts levels were increased by over 10 times. These findings were confirmed by pharmacological inhibition of AKR1B10 activity by Epalrestat. Taken together, these data suggest that AKR1B10 is a critical protein that protects host cells from DNA damage induced by electrophilic carbonyl compounds. AKR1B10 deficiency in the colon may be an important pathogenic factor in disease progression and carcinogenesis. © 2016 Wiley Periodicals, Inc.

Peroxidised dietary lipids impair intestinal function and morphology of the small intestine villi of nursery pigs in a dose-dependent manner

The objective of this study was to investigate the effect of increasing degrees of lipid peroxidation on structure and function of the small intestine of nursery pigs. A total of 216 pigs (mean body weight was 6·5 kg) were randomly allotted within weight blocks and sex and fed one of five experimental diets for 35 d (eleven pens per treatment with three to four pigs per pen). Treatments included a control diet without added lipid, and diets supplemented with 6 % soyabean oil that was exposed to heat (80°C) and constant oxygen flow (1 litre/min) for 0, 6, 9 and 12 d. Increasing lipid peroxidation linearly reduced feed intake (P<0·001) and weight gain (P=0·024). Apparent faecal digestibility of gross energy (P=0·001) and fat (P<0·001) decreased linearly as the degree of peroxidation increased. Absorption of mannitol (linear,P=0·097) andd-xylose (linear,P=0·089), measured in serum 2 h post gavage with a solution containing 0·2 g/ml ofd-xylose and 0·3 g/ml of mannitol, tended to decrease progressively as the peroxidation level increased. Increasing peroxidation also resulted in increased villi height (linear,P<0·001) and crypt depth (quadratic,P=0·005) in the jejunum. Increasing peroxidation increased malondialdehyde concentrations (quadratic,P=0·035) and reduced the total antioxidant capacity (linear,P=0·044) in the jejunal mucosa. In conclusion, lipid peroxidation progressively diminished animal performance and modified the function and morphology of the small intestine of nursery pigs. Detrimental effects were related with the disruption of redox environment of the intestinal mucosa.