Protective effects of raspberry on the oxidative damage in HepG2 cells through Keap1/Nrf2-dependent signaling pathway

Curcumin-Loaded Lipid Nanocarriers: A Targeted Approach for Combating Oxidative Stress in Skin Applications

Background/Objectives: Oxidative stress significantly impacts skin health, contributing to conditions like aging, pigmentation, and inflammatory disorders. Curcumin, with its potent antioxidant properties, faces challenges of low solubility, stability, and bioavailability. This study aimed to encapsulate curcumin in three lipid nanocarriers-solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), and nanoemulsions (NEs)-to enhance its stability, bioavailability, and antioxidant efficacy for potential therapeutic applications in oxidative-stress-related skin disorders. Methods: The lipid nanocarriers were characterized for size, polydispersity index, ζ-potential, and encapsulation efficiency. Stability tests under various conditions and antioxidant activity assays (DPPH and FRAP methods) were conducted. Cytotoxicity in human dermal fibroblasts was assessed using MTT assays, while the expression of key antioxidant genes was evaluated in human dermal fibroblasts under oxidative stress. Skin penetration studies were performed to analyze curcumin's distribution across the stratum corneum layers. Results: All nanocarriers demonstrated high encapsulation efficiency and stability over 90 days. NLCs exhibited superior long-term stability and enhanced skin penetration, while NE formulations facilitated rapid antioxidant effects. Antioxidant assays confirmed that curcumin encapsulation preserved and enhanced its bioactivity, particularly in NLCs. Gene expression analysis revealed upregulation of key antioxidant markers (GPX1, GPX4, SOD1, KEAP1, and NRF2) with curcumin-loaded nanocarriers under oxidative and non-oxidative conditions. Cytotoxicity studies confirmed biocompatibility across all formulations. Conclusions: Lipid nanocarriers effectively enhance curcumin's stability, antioxidant activity, and skin penetration, presenting a targeted strategy for managing oxidative stress in skin applications. Their versatility offers opportunities for tailored therapeutic formulations addressing specific skin conditions, from chronic disorders like psoriasis to acute stress responses such as sunburn.

Anthocyanin-Rich Blackcurrant Supplementation as a Nutraceutical Ergogenic Aid for Exercise Performance and Recovery: A Narrative Review

Athletes and physically active individuals consume sport nutrition supplements to enhance competitive sport performance and exercise recovery. Polyphenols have emerged as a promising area of research with application for sport and exercise nutrition owing to affecting physiologic mechanisms for exercise performance and recovery. The anthocyanin is a polyphenol that can be abundantly present in dark-colored fruits, berries, and vegetables. Anthocyanins and anthocyanin-induced metabolites will provide antioxidant and anti-inflammatory effects. The focus of this narrative review was on the observations with intake of anthocyanin-rich blackcurrant supplements on whole-body exercise performance and exercise recovery. This review included 17 studies with a randomized placebo-controlled crossover design (10 studies on performance and 8 on recovery effects) and 1 with a randomized placebo-controlled parallel group design (recovery effects). Among the performance studies, 6 studies (60%) reported positive effects, 3 studies (30%) reported no significant effects, and 1 study (10%) reported a mixed outcome. Among the recovery studies, 7 studies (78%) reported positive effects, 1 study (11%) reported no significant effects, and 1 study (11%) reported a negative effect. Studies with intake of supplements made from New Zealand blackcurrants (dose: 1.8-3.2 mg/kg and 105-315 mg anthocyanins, acute to 7-d intake) provided meaningful (but not always consistent) effects on continuous and intermittent exercise performance tasks (i.e. rowing, cycling, and running) and markers for exercise recovery. A mechanistic understanding for the beneficial exercise effects of anthocyanins for athletes and physically active individuals is still limited. Future work requires a better understanding of the specific types of anthocyanins and anthocyanin-induced metabolites and their effects on altering cell function that can enhance exercise performance and recovery.

Microbially mediated phenolic catabolites exert differential genoprotective activities in normal and adenocarcinoma cell lines

Age-associated decline of nuclear factor erythroid 2-related factor 2 (Nrf2) activity and DNA repair efficiency leads to the accumulation of DNA damage and increased risk of cancer. Understanding the mechanisms behind increased levels of damaged DNA is crucial for developing interventions to mitigate age-related cancer risk. Associated with various health benefits, (poly)phenols and their microbially mediated phenolic catabolites represent a potential means to reduce DNA damage. Four colonic-microbiota-derived phenolic catabolites were investigated for their ability to reduce H2O2-induced oxidative DNA damage and modulate the Nrf2-Antixoidant Response Element (ARE) pathway, in normal (CCD 841 CoN) and adenocarcinoma (HT29) colonocyte cell lines. Each catabolite demonstrated significant (p < .001) genoprotective activity and modulation of key genes in the Nrf2-ARE pathway. Overall, the colon-derived phenolic metabolites, when assessed at physiologically relevant concentrations, reduced DNA damage in both normal and adenocarcinoma colonic cells in response to oxidative challenge, mediated in part via upregulation of the Nrf2-ARE pathway.

Red raspberry (Rubus idaeus) preserves intestinal barrier integrity and reduces oxidative stress in Caco-2 cells exposed to a proinflammatory stimulus

Growing evidence showed the capacity of (poly)phenols to exert a protective role on intestinal health. Nevertheless, the existing findings are still heterogeneous and the underlying mechanisms remain unclear. This study investigated the potential benefits of a red raspberry (Rubus idaeus) powder on the integrity of the intestinal barrier, focusing on its ability to mitigate the effects of tumor necrosis factor-α (TNF-α)-induced intestinal permeability. Human colorectal adenocarcinoma cells (i.e., Caco-2 cells) were used as a model to assess the impact of red raspberry on intestinal permeability, tight junction expression, and oxidative stress. The Caco-2 cells were differentiated into polarized monolayers and treated with interferon-γ (IFN-γ) (10 ng mL-1) for 24 hours, followed by exposure to TNF-α (10 ng mL-1) in the presence or absence of red raspberry extract (1-5 mg mL-1). The integrity of the intestinal monolayer was evaluated using transepithelial electrical resistance (TEER) and fluorescein isothiocyanate-dextran (FITC-D) efflux assay. Markers of intestinal permeability (claudin-1, occludin, and zonula occludens-1 (ZO-1)) and oxidative stress (8-hydroxy-2-deoxyguanosine (8-OHdG) and protein carbonyl) were assessed using ELISA kits. Treatment with red raspberry resulted in a significant counteraction of TEER value loss (41%; p < 0.01) and a notable reduction in the efflux of FITC-D (-2.5 times; p < 0.01). Additionally, red raspberry attenuated the levels of 8-OHdG (-48.8%; p < 0.01), mitigating the detrimental effects induced by TNF-α. Moreover, red raspberry positively influenced the expression of the integral membrane protein claudin-1 (+18%; p < 0.01), an essential component of tight junctions. These findings contribute to the growing understanding of the beneficial effects of red raspberry in the context of the intestinal barrier. The effect of red raspberry against TNF-α-induced intestinal permeability observed in our in vitro model suggests, for the first time, its potential as a dietary strategy to promote gastrointestinal health.

In vitro digestibility and hepato-protective potential of Lophatherum gracile Brongn. leave extract

Lophatherum gracile Brongn. (L. gracile) is a traditional herb for both medicine and food use, but its digestibility and hepato-protective activity is unknown. Herein we investigated the digestibility and hepato-protective potential of L. gracile leave extract (LGE) using in vitro digestion and alcohol-induced oxidative damage models. Compared to the undigested group, the content of phenolics/flavonoids and the antioxidant activity in LGE generally decreased by 9.30-19.97% in the oral and small intestine phase after digestion, while that increased by 9.96-10.17% in the gastric phase. The main phenolics/flavonoids showed promising stability during digestion and their bio-accessiblity ranged from 67.64% to 84.47%. By reducing cellular reactive oxidative species and malonaldehyde levels, LGE (0.23-0.45 mg/mL) pretreatment significantly ameliorated alcohol-induced oxidative damage in HepG2 cells (P < 0.05), and their survival rate increased from 59.23% to 67.76%. These findings suggested that L. gracile could be used for the development of hepato-protective foods.

Nrf2 signaling pathway: current status and potential therapeutic targetable role in human cancers

Cancer is a borderless global health challenge that continues to threaten human health. Studies have found that oxidative stress (OS) is often associated with the etiology of many diseases, especially the aging process and cancer. Involved in the OS reaction as a key transcription factor, Nrf2 is a pivotal regulator of cellular redox state and detoxification. Nrf2 can prevent oxidative damage by regulating gene expression with antioxidant response elements (ARE) to promote the antioxidant response process. OS is generated with an imbalance in the redox state and promotes the accumulation of mutations and genome instability, thus associated with the establishment and development of different cancers. Nrf2 activation regulates a plethora of processes inducing cellular proliferation, differentiation and death, and is strongly associated with OS-mediated cancer. What's more, Nrf2 activation is also involved in anti-inflammatory effects and metabolic disorders, neurodegenerative diseases, and multidrug resistance. Nrf2 is highly expressed in multiple human body parts of digestive system, respiratory system, reproductive system and nervous system. In oncology research, Nrf2 has emerged as a promising therapeutic target. Therefore, certain natural compounds and drugs can exert anti-cancer effects through the Nrf2 signaling pathway, and blocking the Nrf2 signaling pathway can reduce some types of tumor recurrence rates and increase sensitivity to chemotherapy. However, Nrf2's dual role and controversial impact in cancer are inevitable consideration factors when treating Nrf2 as a therapeutic target. In this review, we summarized the current state of biological characteristics of Nrf2 and its dual role and development mechanism in different tumor cells, discussed Keap1/Nrf2/ARE signaling pathway and its downstream genes, elaborated the expression of related signaling pathways such as AMPK/mTOR and NF-κB. Besides, the main mechanism of Nrf2 as a cancer therapeutic target and the therapeutic strategies using Nrf2 inhibitors or activators, as well as the possible positive and negative effects of Nrf2 activation were also reviewed. It can be concluded that Nrf2 is related to OS and serves as an important factor in cancer formation and development, thus provides a basis for targeted therapy in human cancers.

Raspberry polyphenols alleviate neurodegenerative diseases: through gut microbiota and ROS signals

Neurodegenerative diseases are neurological disorders that become more prevalent with age, usually caused by damage or loss of neurons or their myelin sheaths, such as Alzheimer's disease and epilepsy. Reactive oxygen species (ROS) are important triggers for neurodegenerative disease development, and mitigation of oxidative stress caused by ROS imbalance in the human body is important for the treatment of these diseases. As a widespread delicious fruit, the raspberry is widely used in the field of food and medicine because of its abundant polyphenols and other bioactive substances. Polyphenols from a wide variety of raspberry sources could alleviate neurodegenerative diseases. This review aims to summarize the current roles of these polyphenols in maintaining neurological stability by regulating the composition and metabolism of the intestinal flora and the gut-brain axis signal transmission. Especially, we discuss the therapeutic effects on neurodegenerative diseases of raspberry polyphenols through intestinal microorganisms and ROS signals, by means of summary and analysis. Finally, methods of improving the digestibility and utilization of raspberry polyphenols are proposed, which will provide a potential way for raspberry polyphenols to guarantee the health of the human nervous system.

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.

Mangiferin for the Management of Liver Diseases: A Review

The liver is a digestive and metabolic organ, and several factors can induce liver damage, which is a severe threat to human health. As a natural polyphenolic compound, mangiferin belongs to xanthone glucoside and mainly exists in many plants, such as mango. It is notorious that mangiferin has remarkable pharmacological activities such as anti-inflammatory, anti-tumor, antioxidative stress, antiviral and so on. Emerging evidence indicates the therapeutic benefits of mangiferin against liver disease, including liver injury, nonalcoholic fatty liver disease, alcoholic liver disease, liver fibrosis, and hepatocellular carcinoma. This review aims to summarize the possible underlying signaling mediated by mangiferin in liver disease treatment and the available findings of mangiferin, which can be used to treat different liver diseases and may contribute to mangiferin as a therapeutic agent for liver disease in humans.

Ameliorative effects of different doses of selenium against fluoride-triggered apoptosis and oxidative stress-mediated renal injury in rats through the activation of Nrf2/HO-1/NQO1 signaling pathway

Excess fluoride (F) exposure can cause oxidative stress in the kidney. As an antioxidant, selenium (Se) can potentially protect the kidney from F-induced injury in rats. Hence, the histopathological, renal biochemical, oxidative stress, and apoptotic-related indices upon exposure to 100 mg/L sodium fluoride (NaF) and various doses of sodium selenite (Na₂SeO₃; 0.5, 1, and 2 mg/L) were assessed. Our results demonstrated that F-mediated renal structural damage and apoptosis elevated the content of serum creatinine (SCr), inhibited the activity of catalase (CAT) in serum, and increased the production of reactive oxygen species (ROS) in kidney and malondialdehyde (MDA) in serum. Interestingly, 1 mg/L dietary supplementation of Se tangibly mitigated these injuries. Furthermore, F could also change the gene and protein expression of the nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H quinone oxidoreductase1 (NQO1). Concomitantly, the different concentrations of Se notably alleviated their expression. Taken together, 1-2 mg/L Se ameliorated F-induced renal injury through oxidative stress and apoptosis-related routes. The recorded ameliorative effects might be related to the activation of the Nrf2/HO-1/NQO1 signaling pathway.

Poly(ε-caprolactone)-poly(ethylene glycol) Tri-Block Copolymer as Quercetin Delivery System for Human Colorectal Carcinoma Cells: Synthesis, Characterization and In Vitro Study

Quercetin is a hydrophobic molecule with short blood circulation times and instability. The development of a nano-delivery system formulation of quercetin may increase its bioavailability, resulting in greater tumor suppressing effects. Triblock ABA type polycaprolactone-polyethylenglycol- polycaprolactone (PCL-PEG-PCL) copolymers have been synthetized using ring-opening polymerization of caprolactone from PEG diol. The copolymers were characterized by nuclear magnetic resonance (NMR), diffusion-ordered NMR spectroscopy (DOSY), and gel permeation chromatography (GPC). The triblock copolymers self-assembled in water forming micelles consisting of a core of biodegradable polycaprolactone (PCL) and a corona of polyethylenglycol (PEG). The core-shell PCL-PEG-PCL nanoparticles were able to incorporate quercetin into the core. They were characterized by dynamic light scattering (DLS) and NMR. The cellular uptake efficiency of human colorectal carcinoma cells was quantitatively determined by flow cytometry using nanoparticles loaded with Nile Red as hydrophobic model drug. The cytotoxic effect of quercetin-loaded nanoparticles was evaluated on HCT 116 cells, showing promising results.

Modified rougan decoction alleviates lipopolysaccharide-enrofloxacin-induced hepatotoxicity via activating the Nrf2/ARE pathway in chicken

Liver injury plays a heavy burden on the chicken industry. Although modified rougan decoction is a prescription for the treatment of liver disease based on the classical prescription of rougan decoction (containing peony and licorice). However, the effect and mechanism of modified rougan decoction on the liver remain unclear. In this study, the effects of the water extracts (MRGD) and the alcohol precipitates of water extracts (MRGDE) against lipopolysaccharide-enrofloxacin (LPS-ENR)-induced hepatotoxicity were discussed in vivo and in vitro. The isolated hepatocytes and 128 one-day-old Hyline chickens were considered research objects. The indices of liver injury and oxidative stress were evaluated by hematoxylin and eosin (H&E) stained and the assay kits, and the nuclear erythroid 2-related factor 2 (Nrf2)/antioxidant responsive element (ARE) pathway was detected by the RT-PCR, western blot, and immunofluorescence tests. All data were analyzed using the IBM SPSS 20.0 software. In vivo, the structural integrity of the liver was maintained, AST, ALT, and MDA levels were decreased, and antioxidant enzymes were increased, confirming that the oxidative stress was reduced and liver injury was alleviated. Correspondingly, MRGD and MRGDE were observed to improve cell viability and decrease lactate dehydrogenase (LDH) in vitro, and the cell oxidative damage was reduced. In addition, the nuclear translocation of Nrf2 was improved significantly, and the mRNA and protein expression levels of the related genes were upregulated. In conclusion, MRGD and MRGDE can exert a protective effect against LPS-ENR-induced hepatotoxicity by activating the Nrf2/ARE pathway, which might be a potential therapeutic prescription for preventing or treating liver injury. Notably, no significant difference was found between the 2 extracts, suggesting that a depth extraction method did not always improve the efficacy of natural medicine. Our results provided new insights into finding effective hepatoprotective medicine.

Dietary supplementation with anthocyanin attenuates lipopolysaccharide-induced intestinal damage through antioxidant effects in yellow-feathered broiler chicks

This study investigated the protective effects of anthocyanin (AC) supplementation on lipopolysaccharide (LPS)-challenged yellow-feathered broiler chicks. A total of 480 1-d female broiler chicks were randomly assigned to 4 treatment groups: basal diet (CON), basal diet + LPS-challenge (LPS), supplementation with 100 or 400 mg/kg AC + LPS-challenge (AC100, AC400). On d 17 and d 19, birds in LPS, AC100 and AC400 received an intramuscular dose of LPS, while birds in CON received saline. The result showed that (1) LPS injection significantly decreased (P < 0.05) body weight on d 21 and average daily gain of broiler chicks from 1 to 21 days of age, and supplementation with 100 mg/kg AC increased (P < 0.05) those of LPS-challenged broilers. (2) There were no differences among the treatments (P > 0.05) in relative weights of immune organs. (3) Supplementation with AC (AC100 and AC400) increased (P < 0.05) the jejunal villus height and villus height/crypt depth ratio (AC100) of LPS-challenged birds. Challenge with LPS decreased the relative expression of OCLN (Occludin), ZO-1, JAM2, and MUC2 in jejunal mucosa of broilers, and supplementation with AC offset the relative expression of ZO-1, JAM2 (AC100 and AC400), and OCLN (AC400) in LPS-injected broilers. (4) LPS-induced increase in the malondialdehyde (MDA) concentration and decreases in activity of total superoxide dismutase (T-SOD), and expression of SOD1, CAT and GPX in jejunal mucosa, were attenuated by dietary AC supplementation. In conclusion, in yellow-feathered broiler chicks, dietary supplementation with AC alleviated LPS-induced declined growth performance and mucosal damage of the intestine through antioxidant effects.

Maize Flavonoid Biosynthesis, Regulation, and Human Health Relevance: A Review

Maize is one of the most important crops for human and animal consumption and contains a chemical arsenal essential for survival: flavonoids. Moreover, flavonoids are well known for their beneficial effects on human health. In this review, we decided to organize the information about maize flavonoids into three sections. In the first section, we include updated information about the enzymatic pathway of maize flavonoids. We describe a total of twenty-one genes for the flavonoid pathway of maize. The first three genes participate in the general phenylpropanoid pathway. Four genes are common biosynthetic early genes for flavonoids, and fourteen are specific genes for the flavonoid subgroups, the anthocyanins, and flavone C-glycosides. The second section explains the tissue accumulation and regulation of flavonoids by environmental factors affecting the expression of the MYB-bHLH-WD40 (MBW) transcriptional complex. The study of transcription factors of the MBW complex is fundamental for understanding how the flavonoid profiles generate a palette of colors in the plant tissues. Finally, we also include an update of the biological activities of C3G, the major maize anthocyanin, including anticancer, antidiabetic, and antioxidant effects, among others. This review intends to disclose and integrate the existing knowledge regarding maize flavonoid pigmentation and its relevance in the human health sector.

Targeting Nrf2/Keap1 signaling pathway by bioactive natural agents: Possible therapeutic strategy to combat liver disease

BACKGROUND

Nuclear factor erythroid 2-related factor (Nrf2), a stress-activated transcription factor, has been documented to induce a defense mechanism against oxidative stress damage, and growing evidence considers this signaling pathway a key pharmacological target for the treatment of liver diseases.

PURPOSE

The present review highlights the role of phytochemical compounds in activating Nrf2 and mitigate toxicant-induced stress on liver injury.

METHODS

A comprehensive search of published articles was carried out to focus on original publications related to Nrf2 activators against liver disease using various literature databases, including the scientific Databases of Science Direct, Web of Science, Pubmed, Google, EMBASE, and Scientific Information (SID).

RESULTS

Nrf2 activators exhibited promising effects in resisting a variety of liver diseases induced by different toxicants in preclinical experiments and in vitro studies by regulating cell proliferation and apoptosis as well as an antioxidant defense mechanism. We found that the phytochemical compounds, such as curcumin, naringenin, sulforaphane, diallyl disulfide, mangiferin, oleanolic acid, umbelliferone, daphnetin, quercetin, isorhamnetin-3-O-galactoside, hesperidin, diammonium glycyrrhizinate, corilagin, shikonin, farrerol, and chenpi, had the potential to improve the Nrf2-ARE signaling thereby combat hepatotoxicity.

CONCLUSION

Nrf2 activators may offer a novel potential strategy for the prevention and treatment of liver diseases. More extensive studies are essential to identify the underlying mechanisms and establish future therapeutic potentials of these signaling modulators. Further clinical trials are warranted to determine the safety and effectiveness of Nrf2 activators for hepatopathy.

Effect of pinolenic acid on oxidative stress injury in HepG2 cells induced by H2O2

To investigate the effect and mechanism of pinolenic acid (PNA) on H2O2-induced oxidative stress injury in HepG2 cells. Methods: PNA was used to regulate oxidative stress injury of HepG2 cells induced by H2O2. Quantification of cell survival rate, accumulation of intracellular reactive oxygen species (ROS), and expression levels of anti-oxidation-related genes were determined using MTT, fluorescent probe technology (DCFH-DA), and real-time quantitative reverse transcription polymerase chain technology (qRT-PCR) method, respectively. Meanwhile, the activity of intracellular antioxidant enzymes was determined by biochemical methods. The results showed that PNA improved the survival rate of HepG2 cells induced by H2O2 (29.59%, high-dose group), reduced the accumulation of intracellular ROS (65.52%, high-dose group), and reduced the level of intracellular malondialdehyde (MDA; 65.52%, high-dose group). All these results were dose-dependent, which indicated that PNA can improve oxidative stress damage of cells. Furthermore, the mechanism of PNA regulating oxidative stress was investigated from the gene level. Results showed that under supplementation of PNA, the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) had been improved (39.74%, 17.58%, and 23.83%, high-dose group). Further studies on gene expression which controls the activity of antioxidant enzymes showed that under the regulation of PNA, the expression level of Keap1 gene was decreased, while Nrf2 gene was increased. The expression levels of HO-1 and NQO1 in the downstream of Nrf2 were increased. Results indicated that under the regulation of PNA, Nrf2 was separated from Keap1, entered the nucleus, bound to ARE, and up-regulated the expression levels of HO-1 and NQO1 genes. Conclusion: PNA has a conspicuous improvement effect on oxidative stress damage induced by H2O2 in HepG2 cells. We also found the antioxidant mechanisms of PNA where it protected cells from oxidative stress damage by causing nuclear translocation of Nrf2 gene and up-regulated the expression levels of antioxidant enzymes in the downstream. This shows that PNA prevented oxidative stress by mediating the Keap1/Nrf2 transcriptional pathway and down-regulating enzyme activities.

MicroRNAs Involved in Oxidative Stress Processes Regulating Physiological and Pathological Responses

Oxidative stress influences several physiological and pathological cellular events, including cell differentiation, excessive growth, proliferation, apoptosis, and the inflammatory response. Therefore, oxidative stress is involved in the pathogenesis of various diseases, including pulmonary fibrosis, epilepsy, hypertension, atherosclerosis, Parkinson's disease, cardiovascular disease, and Alzheimer's disease. Recent studies have shown that several microRNAs (miRNAs) are involved in developing various diseases caused by oxidative stress and that miRNAs may be helpful to determine the inflammatory characteristics of immune responses during infection and disease. This review describes the known effects of miRNAs on reactive oxygen species to induce oxidative stress and the miRNA regulatory mechanisms involved in the uncoupling of Keap1-Nrf2 complexes. Finally, we summarized the functions of miRNAs in several antioxidant genes. Understanding the crosstalk between miRNAs and oxidative stress-inducing factors during physiological and pathological cellular events may have implications for designing more effective treatments for immune diseases.

Effects of Dietary Supplementation with Bilberry Extract on Growth Performance, Immune Function, Antioxidant Capacity, and Meat Quality of Yellow-Feathered Chickens

Simple Summary

Various plant extracts are used as functional nutritional factors to keep the health and improve the performance of animals. This research investigated the effects of bilberry extract (effective ingredient: anthocyanin) on growth performance, meat quality, antioxidant status, and immune function of yellow-feathered chickens. Results showed that dietary supplementation with bilberry extract enhanced relative weight of the bursa of Fabricius and broadly increased activities of antioxidant enzymes of chickens; indices of meat quality were improved without impact on growth performance. The finding indicated that bilberry extract might be considered as a new additive to improve the health and meat quality of yellow-feathered chickens.

Abstract

The experiment was conducted to investigate the effects of bilberry extract on growth performance, meat quality, antioxidant status, and immune function of yellow-feathered chickens. A total of 360 female hatchling Lingnan chickens were randomly allocated to three treatments with 6 replicates of 20 chickens per replicate. Birds were fed a basal diet supplemented with 0 (the control group), 100 (B100), and 400 (B400) mg/kg of bilberry extract for 63 d. Compared with the controls, (1) dietary supplementation with bilberry extract did not affect the growth performance of chickens from 1 to 63 d. (2) At 21 d, the relative weight of the bursa of Fabricius was increased (p < 0.05) by dietary supplementation with 400 mg/kg bilberry extract. Bilberry extract decreased the concentrations of IgY and IgM in blood plasma of 63-d chickens (p < 0.05). (3) For 21-d chickens, dietary supplementation with 400 mg/kg bilberry extract increased (p < 0.05) the activity of GSH-Px in blood plasma and jejunal mucosa (p < 0.05). Supplementation with 100 mg/kg bilberry extract increased (p < 0.05) the activities of T-SOD in jejunal mucosa and GSH-Px in the liver and decreased (p < 0.05) the MDA concentration in the liver. For chickens at the age of 63 d, both levels of bilberry extract increased activity of T-SOD in blood plasma (p < 0.05) and reduced MDA concentration in the jejunum (p < 0.05). (4) Supplementation with bilberry extract in the diet decreased the MDA concentration (B100) in muscle of 63-d chickens at 45 min postmortem and increased (p < 0.05) the activity of T-SOD (B400) at 4 d postmortem. (5) In breast muscle at 63 d, birds supplemented with bilberry extract (B400) had increased pH and drip loss while drip loss was reduced in the B100 treatment (p < 0.05); treatments did not affect inosinic acid or intramuscular fat contents. In conclusion, dietary supplementation of yellow-feathered chickens with bilberry extract enhanced the relative weight of the bursa of Fabricius, and broadly increased activities of antioxidant enzymes; indices of meat quality were improved without impact on growth performance. Considering the results in the current research, 100 mg/kg bilberry extract was recommended when supplemented in chickens.

PbAc Triggers Oxidation and Apoptosis via the PKA Pathway in NRK-52E Cells

This study aimed to investigate the mechanism of the lead exposure-induced oxidative stress and apoptosis of renal tubular epithelial cells. We explored the effects of lead acetate (PbAc) on the oxidation and apoptosis of renal proximal tubular cells (NRK-52E) through in vitro experiments. Results showed that PbAc induced dose-dependent reactive oxygen species (ROS) accumulation in NRK-52E cells, and the activities of superoxide dismutase (SOD) and glutathione (GSH) decreased, whereas the malondialdehyde (MDA) content increased. Under the exposure of 40 and 80 μM PbAc, the mRNA level of B cell lymphoma-2 (Bcl-2) in the cells decreased, the mRNA levels of Bcl-2-associated X protein (Bax) and caspase-3 increased, and apoptosis was obvious. Furthermore, the nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) activity was enhanced by PbAc in a dose-dependent manner. The mRNA levels of protein kinase A (PKA) were upregulated by PbAc. H-89, a PKA inhibitor, suppressed PKA activation, ROS accumulation, and Nox4 activity in NRK-52E cells. Our results indicated that PbAc potentially stimulated oxidative stress and apoptosis in NRK-52E cells by increasing Nox4-dependent ROS production via the PKA signaling pathway.

The pleiotropic effects of Prunus avium L. extract against oxidative stress on human fibroblasts. An in vitro approach

There is a persistent interest in innovative and multifunctional ingredients in biology research. With regards to this, natural sources have an important role due to their multiple benefits. Thus, this study aims to present the pleiotropic activity of Prunus avium L. extract on human primary fibroblasts for proving its efficacy in dermis-related processes. We focused on the safety and efficacy assessments based on cytotoxicity and gene expression analysis under oxidative stress. Specifically, Prunus avium L. extract was proved non-cytotoxic in human fibroblasts. The gene expression analysis unveiled that this extract has in vitro protective properties on human dermal fibroblasts under oxidative stress related to antioxidant activity, anti-inflammatory response, cell proliferation and cell- aging. Our study demonstrated for the very first time that the Prunus avium L. extract is a multifunctional ingredient as it mediates several human dermis-related in vitro processes highlighting its potential to be used as an active ingredient in skin care products.

Yi-Qi-Jian-Pi Formula Suppresses RIPK1/RIPK3-Complex-Dependent Necroptosis of Hepatocytes Through ROS Signaling and Attenuates Liver Injury in Vivo and in Vitro

Acute-on-chronic liver failure (ACLF) is described as a characteristic of acute jaundice and coagulation dysfunction. Effective treatments for ACLF are unavailable and hence are urgently required. We aimed to define the effect of Yi-Qi-Jian-Pi Formula (YQJPF) on liver injury and further examine the molecular mechanisms. In this study, we established CCl₄-, LPS-, and d-galactosamine (D-Gal)-induced ACLF rat models in vivo and LPS- and D-Gal-induced hepatocyte injury models in vitro. We found that YQJPF significantly ameliorates liver injury in vivo and in vitro that is associated with the regulation of hepatocyte necroptosis. Specifically, YQJPF decreased expression of receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3) and pseudokinase mixed lineage kinase domain-like (MLKL) to inhibit the migration of RIPK1 and RIPK3 into necrosome. YQJPF also reduces the expression of inflammatory cytokines IL-6, IL-8, IL-1β, and TNF-α, which were regulated by RIPK3 mediates cell death. RIPK1 depletion was found to enhance the protective effect of YQJPF. Furthermore, we showed that YQJPF significantly downregulates the mitochondrial reactive oxygen species (ROS) production and mitochondrial depolarization, with ROS scavenger, 4-hydroxy-TEMPO treatment recovering impaired RIPK1-mediated necroptosis and reducing the expression of IL-6, IL-8, IL-1β, and TNF-α. In summary, our study revealed the molecular mechanism of protective effect of YQJPF on hepatocyte necroptosis, targeting RIPK1/RIPK3-complex-dependent necroptosis via ROS signaling. Overall, our results provided a novel perspective to indicate the positive role of YQJPF in ACLF.

The structural characteristic of acidic-hydrolyzed corn silk polysaccharides and its protection on the H2O2-injured intestinal epithelial cells

This work aims to describe the purification and characterization of acidic-hydrolyzed corn silk polysaccharides (AH-CSP) and evaluate their protection on the H₂O₂-injured intestinalepithelial cells (IEC-6). Two fractions named AHP-1 and AHP-2 were obtained from AH-CSP, and physicochemical properties of them were investigated by gel permeation chromatography (GPC), gas chromatography (GC), nuclear magnetic resonance (NMR), fourier transform infrared (FT-IR) spectroscopy, scanning electronic microscopy (SEM), and Congo red test. Results showed that AHP-1 (2.80 × 10⁴ Da) and AHP-2 (1.25 × 10⁴ Da) were consisted of xylose, mannose, galactose, rhamnose, arabinose, and glucose. AHP-1 and AHP-2 had strong scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-Azobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and OH· free radicals. Furthermore, pretreatment with AHP-2 could protect the H₂O₂-injured IEC-6 cells by effectively scavenging the overproduced reactive oxygen species (ROS) and regulating of Kelch-like ECH-associated protein 1(Keap1)/ nuclear factor erythroid 2-related factor 2 (Nrf2) signal pathway.

Potential of anthocyanin as an anti-inflammatory agent: a human clinical trial on type 2 diabetic, diabetic at-risk and healthy adults

OBJECTIVE

The present research aimed to investigate the anti-inflammatory potential of dietary anthocyanin (ACN) in type 2 diabetic (T2D), T2D-at-risk and healthy individuals. Furthermore, dietary inflammatory index (DII) was used to study the association of diet with biomarkers of inflammation.

RESEARCH METHODS

An open-label clinical trial was conducted at Griffith University investigating the efficacy of 320 mg ACN supplementation per day over the course of 4 weeks. Diabetes-associated inflammatory biomarkers and relevant biochemical and physical parameters were tested pre-and post-intervention, and participants' dietary inflammatory potential was estimated.

RESULTS

A significant reduction in the pro-inflammatory biomarkers' interleukin-6, interleukin-18, and tumour necrosis factor-α was observed in the T2D group. In addition, some, but not all, biochemical parameters including fasting blood glucose, low-density lipoprotein cholesterol and uric acid were significantly improved in T2D-at-risk group. Moreover, a significant difference was detected between the DII scores of the healthy and T2D groups. DII score for the T2D group was consistent with an anti-inflammatory diet.

CONCLUSION

Anti-inflammatory potential of dietary ACN in T2D participants was evidenced in the present study. Although, anti-inflammatory dietary patterns of T2D participants may have accelerated the anti-inflammatory effect of the ACN capsules supplemented in this trial.

Oleoylethanolamide Protects Against Acute Liver Injury by Regulating Nrf-2/HO-1 and NLRP3 Pathways in Mice

Acute liver injury is a rapidly deteriorating clinical condition with markedly high morbidity and mortality. Oleoylethanolamide (OEA) is an endogenous lipid messenger with multiple bioactivities, and has therapeutic effects on various liver diseases. However, effects of OEA on acute liver injury remains unknown. In this study, effects and mechanisms of OEA in lipopolysaccharide (LPS)/d-galactosamine (D-Gal)-induced acute liver injury in mice were investigated. We found that OEA treatment significantly attenuated LPS/D-Gal-induced hepatocytes damage, reduced liver index (liver weight/body weight), decreased plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels. Moreover, mechanism study suggested that OEA pretreatment significantly reduced hepatic MDA levels, increased Superoxide dismutase (SOD) and Glutathione peroxidase (GSH-PX) activities via up-regulate Nrf-2 and HO-1 expression to exert anti-oxidation activity. Additionally, OEA markedly reduced the expression levels of Bax, Bcl-2 and cleaved caspase-3 to suppress hepatocyte apoptosis. Meanwhile, OEA remarkedly reduced the number of activated intrahepatic macrophages, and alleviated the mRNA expression of pro-inflammatory factors, including TNF-α, IL-6, MCP1 and RANTES. Furthermore, OEA obviously reduced the expression of IL-1β in liver and plasma through inhibit protein levels of NLRP3 and caspase-1, which indicated that OEA could suppress NLRP3 inflammasome pathway. We further determined the protein expression of PPAR-α in liver and found that OEA significantly increase hepatic PPAR-α expression. In addition, HO-1 inhibitor ZnPP blocked the therapeutic effects of OEA on LPS/D-Gal-induced liver damage and oxidative stress, suggesting crucial role of Nrf-2/HO-1 pathway in the protective effects of OEA in acute liver injury. Together, these findings demonstrated that OEA protect against the LPS/D-Gal-induced acute liver injury in mice through the inhibition of apoptosis, oxidative stress and inflammation, and its mechanisms might be associated with the Nrf-2/HO-1 and NLRP3 inflammasome signaling pathways.

Hypoxia-reoxygenation treatment attenuates gestational diabetes mellitus

BACKGROUND

Oxidative stress leads to insulin resistance and gestational diabetes mellitus (GDM). The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling is an important anti-oxidative stress pathway, which can be activated by hypoxia-reoxygenation (H/R) treatment. We aimed to demonstrate the effects of H/R treatment on GDM symptoms as well as reproductive outcomes.

METHODS

Pregnant C57BL/KsJ db/+ mice were used as a genetic GDM model. Plasma insulin and other biochemical indexes of plasma, insulin sensitivity, glucose intolerance, blood glucose and liver biochemical indexes were evaluated. Protein abundance of HO-1 and Nrf2 were assessed with Western blot.

RESULTS

H/R treatment markedly ameliorated β-cell insufficiency and glucose intolerance, suppressed oxidative stress in vivo, stimulated the activities of anti-oxidant enzymes, and led to improved reproductive outcomes. The beneficial effects of H/R treatment were mechanistically mediated via the restoration of Nrf2/HO-1 anti-oxidant signaling pathway in the liver of GDM mice.

CONCLUSION

Our study, for the first time, suggests that H/R treatment is a potentially novel therapeutic approach against GDM symptoms, by activating the Nrf2/HO-1 signaling pathway and inhibiting oxidative stress.

Separation of constituents from Bergenia stracheyi (Hook. F. & Thoms.) Engl. by high-speed countercurrent chromatography with elution mode and its antidiabetic and antioxidant in vitro evaluation

Diabetes, a metabolic disorder, is caused by a high blood sugar level. Diabetes is an increasing health issue and search for potent antidiabetic agents is desirable. Owing to its ethnomedicinal value, the Himalayan perennial herb Bergenia stracheyi (Hook. f. & Thoms.) Engl. (Saxifragaceae Juss) is used to treat diabetes. Herein, an efficient high-speed countercurrent chromatography with elution mode is reported for separation of active compounds from B. stracheyi. In current investigation, six main compounds including β-arbutin (1), bergenin (2), 6-O-galloylarbutin (3), gallic acid (4), 11-O-galloylbergenin (5), and (-)-epicatechin 3-O-gallate (6) with above 95% purity were efficiently separated in a single run using biphasic tert-butyl methyl ether/n-butanol/methanol/water (1:3:1:5, v/v/v/v) solvent system. The structures of these compounds were characterized using spectral techniques and compared with the literature. Antidiabetic and antioxidant activities evaluation of the study samples showed that β-arbutin (1) and 6-O-galloylarbutin (3) have a significant protective effect, especially at high dose against hydrogen peroxide induced oxidative injury. Our results might help further in-depth phytochemical and biological evaluation studies in search of potent antidiabetic compounds from B. stracheyi.

Protective effect of Pinot noir pomace extract against the cytotoxicity induced by polycyclic aromatic hydrocarbons on endothelial cells

Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants found in the air generated mainly by the combustion of coal or biomass burning. Exposure to Polycyclic Aromatic Hydrocarbons is positively correlated with cardiovascular diseases. Phenolic compounds are widely found in the plant kingdom, and their availability from agri-food processing waste has led to an increased interest in their recovery. The production of large amounts of organic waste created by the wine industry has emphasized the valuation of these wastes to generate high-added-value by-products. The objective of this work was to investigate the protective effect of Pinot noir pomace extract on human endothelial cells against PAHs found in the polluted air of Temuco, Chile. The pomace extract was characterized by spectrophotometric analysis and high-performance liquid chromatography (HPLC). Results revealed the presence of 5 glycosylated anthocyanins and 9 low molecular weight polyphenols. Molecular docking indicated that cyanidin-3-glucoside (-9.2 kcal/mol) and quercetin (-9.6 kcal/mol) had the highest affinities for the Nrf2 binding site in the Keap1 protein, suggesting a possible competition with this transcription factor. Endothelial cells from the human umbilical vein were exposed to increasing concentrations of Phenanthrene, Fluoranthene, and Pyrene diluted in DMSO in a ratio of 3:1:1 (10 μM-200 μM). Viability through the MTS assay showed that 150 μM of PAHs was sufficient to reduce viability by 75% (p ˂ 0.0001). When the cells were pre-treated with 400 μg/ml of the extract, 150 μM of PAHs did not exert cell death (80% viability). Our preliminary results show that polyphenolic components found in Pinot noir pomace might have a beneficial effect as a protective agent.

Marine Fungus Aspergillus chevalieri TM2-S6 Extract Protects Skin Fibroblasts from Oxidative Stress

The strain Aspergillus chevalieri TM2-S6 was isolated from the sponge Axinella and identified according to internal transcribed spacer (ITS) molecular sequence homology with Aspergillus species from the section Restricti. The strain was cultivated 9 days on potato dextrose broth (PDB), and the medium evaluated as antioxidant on primary normal human dermal fibroblasts (NHDF). The cultivation broth was submitted to sterile filtration, lyophilized and used without any further processing to give the Aspergillus chevalieri TM2-S6 cultivation broth ingredient named ACBB. ACCB contains two main compounds: tetrahydroauroglaucin and flavoglaucin. Under oxidative stress, ACCB showed a significant promotion of cell viability. To elucidate the mechanism of action, the impact on a panel of hundreds of genes involved in fibroblast physiology was evaluated. Thus, ACCB stimulates cell proliferation (VEGFA, TGFB3), antioxidant response (GPX1, SOD1, NRF2), and extracellular matrix organization (COL1A1, COL3A1, CD44, MMP14). ACCD also reduced aging (SIRT1, SIRT2, FOXO3). These findings indicate that Aspergillus chevalieri TM2-S6 cultivation broth exhibits significant in vitro skin protection of human fibroblasts under oxidative stress, making it a potential cosmetic ingredient.

Inhibition of USP15 Prevent Glutamate-Induced Oxidative Damage by Activating Nrf2/HO-1 Signaling Pathway in HT22 Cells

Oxidative stress has been identified as the significant mediator in epilepsy, which is a chronic disorder in central nervous system. About 30% of epilepsy patients are refractory to antiepileptic drug treatment. However, the underlying mechanism of oxidative damage in epilepsy needs further investigation. In our study, we first find that ubiquitin-specific peptidase 15 (USP15) expression was upregulated in a pentylenetetrazole (PTZ) kindled rat model of epilepsy. Silencing USP15 protected against glutamate-mediated neuronal cell death, and inhibited the high expression levels of cleaved caspase-3. Knockout of USP15 significantly reduced intracellular reactive oxygen species (ROS) levels and enhanced superoxide dismutase (SOD) activity in HT22 cells under the exposure to glutamate treatment. Furthermore, USP15 inhibition induced nuclear factor erythroid-derived 2-related factor2 (Nrf2) nuclear translocation and promoted protein expression level of heme oxygenase (HO-1). Taken together, our findings first reveal a role of USP15 in the pathogenesis of epilepsy, and silencing USP15 in vitro protects against glutamate-mediated cytotoxicity in HT22 cells. Pharmacological inhibition of USP15 may alleviate epileptic seizures via fighting against oxidative damage, providing a novel antiepileptic target.

In vitro protective effects of marine-derived Aspergillus puulaauensis TM124-S4 extract on H2O2-stressed primary human fibroblasts

Nowadays, there is a huge interest in natural products obtained from marine organisms that can promote human health.The aim of the present study is to evaluate for the first time, the in vitro effects of marine Aspergillus puulaauensis TM124-S4 extract against oxidative stress in human fibroblasts, and its potential as a cosmetic ingredient. The strain was isolated from the Mediterranean Sea star, Echinaster sepositus, and identified according to ITS molecular sequence homology as a member of Aspergillus section versicolores.To gain insight on the bioactivity underpinning the effects of TM124-S4 extract on oxidative stress, we examined a panel of a hundred genes as well as cell viability. Initially, Aspergillus puulaauensis TM124-S4 promoted cell viability.The change in gene transcripts revealed that Aspergillus puulaauensis TM124-S4 extracts exhibited skin protection properties by mediating cell proliferation (EPS8, GDF15, CASP7, VEGFA), antioxidant response (CAT, SOD1, TXN, GPX1), skin hydration (CD44, CRABP2, SERPINE) and DNA repair (PCNA, P21). The extract also modulated the expression of genes involved in skin pigmentation and aging (TYR, FOXO3).These findings indicate that Aspergillus puulaauensis TM124-S4 extract possesses significant in-vitro skin protection activity against induced oxidative stress.Furthermore, new insights are provided into the beneficial role of fungal bioactive compounds in skin related research.

Anti-Ageing Effect of Physalis alkekengi Ethyl Acetate Layer on a d-galactose-Induced Mouse Model through the Reduction of Cellular Senescence and Oxidative Stress

We aimed to study the effects of an ethyl acetate fraction of Physalis alkekengi (PAE) on d-galactose (d-gal)-induced senescence and the underlying mechanism. Firstly, analysis of the phytochemical composition revealed total flavonoids, total phenolics, total saponins, rutin, and luteolin contents of 71.72 ± 2.99 mg rutin equivalents/g, 40.19 ± 0.47 mg gallic acid equivalents/g, 128.13 ± 1.04 mg oleanolic acid equivalents/g, 1.67 ± 0.07 mg/g and 1.61 ± 0.01 mg/g, respectively. The mice were treated with d-gal for six weeks, and from the fifth week, the mice were administered with PAE by gavage once a day for five weeks. We found significant d-gal-induced ageing-related changes, such as learning and memory impairment in novel object recognition and Y-maze, fatigue in weight-loaded forced swimming, reduced thymus coefficient, and histopathological injury of the liver, spleen, and hippocampus. The PAE effectively protected from such changes. Further evaluation showed that PAE decreased the senescence-associated β-galactosidase of the liver, spleen, and hippocampus, as well as the oxidative stress of the liver, plasma, and brain. The abundance of flavonoids, phenols, and saponins in PAE may have contributed to the above results. Overall, this study showed the potential application of PAE for the prevention or treatment of ageing-associated disorders.

Phenolics and Carotenoid Contents in the Leaves of Different Organic and Conventional Raspberry (Rubus idaeus L.) Cultivars and Their In Vitro Activity

Raspberry leaves are a source of carotenoids and polyphenols, including ellagic acid and salicylic acid. The results of scientific research suggest that they have potential pro-health properties that contribute to human health. The aim of this study was to determine the polyphenolic and carotenoid profiles in the leaves of selected raspberry cultivars and their in vitro activity. The second aim was to determine the impact of organic and conventional farm management on the polyphenol, carotenoid, and chlorophyll contents in different raspberry cultivars: ‘Polana’, ‘Polka’, ‘Tulameen’, ‘Laszka’ and ‘Glen Ample’. Compared with conventional raspberry leaves, organic raspberry leaves were characterized by a significantly higher content of dry matter, total polyphenols, total phenolic acids, chlorogenic acid, caffeic acid, salicylic acid and quercetin-3-O-rutinoside; moreover, the organic leaves were characterized by higher antioxidant activity. Among examined cultivars, ‘Polka’ c. was characterized by the highest antioxidant status. However, raspberry leaves from conventional farms contained more total carotenoids, violaxanthin, alpha-carotene, beta-carotene, total chlorophyll and individual forms of chlorophylls: a and b.