Chemical characterization of the avenanthramide-rich extract from oat and its effect on D-galactose-induced oxidative stress in mice

Phenolic amides (avenanthramides) in oats - an update review

Oats (Avena sativa L.) are one of the worldwide cereal crops. Avenanthramides (AVNs), the unique plant alkaloids of secondary metabolites found in oats, are nutritionally important for humans and animals. Numerous bioactivities of AVNs have been investigated and demonstrated in vivo and in vitro. Despite all these, researchers from all over the world are taking efforts to learn more knowledge about AVNs. In this work, we highlighted the recent updated findings that have increased our understanding of AVNs bioactivity, distribution, and especially the AVNs biosynthesis. Since the limits content of AVNs in oats strictly hinders the demand, understanding the mechanisms underlying AVN biosynthesis is important not only for developing a renewable, sustainable, and environmentally friendly source in both plants and microorganisms but also for designing effective strategies for enhancing their production via induction and metabolic engineering. Future directions for improving AVN production in native producers and heterologous systems for food and feed use are also discussed. This summary will provide a broad view of these specific natural products from oats.

Nutraceutical Properties of Medicago sativa L., Agave Spp., Zea mays L. and Avena sativa L.: A Review of Metabolites and Mechanisms

Plants are the main sources of bioactive compounds (nutraceuticals) that function under different mechanisms of action for the benefit of human health. Mexico ranks fifth in the world in biodiversity, offering opportunities for healthy food. An important variety of crops are produced in the state of Hidalgo, e.g., based on the 2021 production, alfalfa, oats, maguey, and corn. The present review presents the latest findings of these crops, regarding the benefits they provide to health (bioactivity, nutraceuticals), and presents the compounds and mechanisms identified by which the benefit is provided. The knowledge compiled here is for the benefit of the recovery of the crops, the recognition of their bioactivities, in search of identifying the best routes of action for prevention, treatment and possible cure of chronic degenerative diseases (thereby promoting crop valorization). Exhaustive bibliographic research was carried out by means of engines and scientific databases. Articles published between 2001 and 2022 that included specific keywords (Scopus, EMBASE, EBSCO, PubMed, Science Direct, Web of Science, Google Scholar). Outstanding activities have been identified for the compounds in the crops, such as antiinflammatory, anticholesterolemic, antihypertensive, antidiabetic, anticancer, antimicrobial, antioxidant, and chelating. The compounds that provide these properties are total phenols, phenolic acids, tannins, anthocyanins, carotenoids, iso-flavones, phytosterols, saponins, fructans, glycosides, glucans, avenanthramides, and polysaccharides.

Protective Effects of Water Extract of Fructus Ligustri Lucidi against Oxidative Stress-Related Osteoporosis In Vivo and In Vitro

Fructus Ligustri Lucidi (FLL) is the fruit of Ligustrum lucidum Ait and is a component of many kidney-tonifying traditional Chinese medicine formulae for treating osteoporosis. Accumulating evidence has linked oxidative stress with the progression of bone diseases. The present study aimed to identify the effects of FLL on oxidative stress-related osteoporosis in vivo and in vitro. To construct animal models, we utilized d-galactose (D-gal) injection to induce oxidative stress combined with a low calcium (the exact percentage in the diet was 0.1%) diet. Thirteen-week-old Kunming female mice were gavaged with water extract of FLL for 20 days. Then, eight-month-old Kunming female mice were treated with FLL under standard administration and diet as the aged group. In vitro, MC3T3-E1 cells stimulated by H₂O₂ were treated with FLL for 24 h. The micro-CT results showed that the modeling approach combining oxidative stress with a low calcium diet caused low conversion type osteoporosis in mice. FLL exerted a prominent effect on preventing osteoporosis by inhibiting oxidative stress, increasing bone mineral density (BMD), improving bone microstructure, and promoting osteoblast proliferation and osteoprotegerin (OPG) protein expression; however, FLL had no therapeutic effect on bone loss in aged mice. In conclusion, FLL showed outstanding anti-bone loss ability both in vivo and in vitro and could probably be developed as a prophylactic agent for osteoporosis.

Inhibitory Effect of Avenanthramides (Avn) on Tyrosinase Activity and Melanogenesis in α-MSH-Activated SK-MEL-2 Cells: In Vitro and In Silico Analysis

Melanin causes melasma, freckles, age spots, and chloasma. Anti-melanogenic agents can prevent disease-related hyperpigmentation. In the present study, the dose-dependent tyrosinase inhibitory activity of Avenanthramide (Avn)-A-B-C was demonstrated, and 100 µM Avn-A-B-C produced the strongest competitive inhibition against inter-cellular tyrosinase and melanin synthesis. Avn-A-B-C inhibits the expression of melanogenesis-related proteins, such as TRP1 and 2. Molecular docking simulation revealed that AvnC (−7.6 kcal/mol) had a higher binding affinity for tyrosinase than AvnA (−7.3 kcal/mol) and AvnB (−6.8 kcal/mol). AvnC was predicted to interact with tyrosinase through two hydrogen bonds at Ser360 (distance: 2.7 Å) and Asn364 (distance: 2.6 Å). In addition, AvnB and AvnC were predicted to be skin non-sensitizers in mammals by the Derek Nexus Quantitative Structure–Activity Relationship system.

Antioxidant Activity and Mechanism of Avenanthramides: Double H+/e- Processes and Role of the Catechol, Guaiacyl, and Carboxyl Groups

Avenanthramides (AVAs), unique phenolic compounds in oats, have attracted increasing interest due to their health benefits. Eight representative AVAs were studied using the density functional theory (DFT) method to elucidate their antioxidant activity and mechanism. Preference of different mechanisms was evaluated based on thermodynamic descriptors involved in double (2H⁺/2e^-) free radical scavenging reactions. It was found that the hydrogen atom transfer (HAT) mechanism is more favorable in the gas and benzene phases, while sequential proton loss electron transfer (SPLET) is preferred in polar media. The results suggest the feasibility of the double HAT and double SPLET mechanisms for 2s and c-series AVAs. The sequential triple proton loss double electron transfer (StPLdET) mechanism represents the dominant pathway in aqueous solution at physiological pH. In addition, the sequential proton loss hydrogen atom transfer (SPLHAT) mechanism provides an alternative pathway to trap free radicals. Results also revealed the important role of the catechol, guaiacyl, and carboxyl moieties.

The Role of Solid Particles Obtained from Plant Materials in Improvement the Quality of Cosmetic Care Balms

The sensory properties of cosmetic emulsions are part of the basic properties of products such as face creams and body balms. They are extremely important parameters in the product evaluation by consumers. Cosmetics manufacturers are increasingly introducing ingredients in the form of solid particles (talc, bentonite, clay) into formulations to improve the sensory properties of products. Their addition simplifies the application of the emulsion on the skin, effects faster absorption and leaves a feeling of silky smoothness after application. During the work, we investigated solid particles of plant origin: powder from ground orange peel and oat grain. These ingredients were introduced into the formulation of the model body balms. The antioxidant and physicochemical properties of the obtained emulsions as well as the skin hydration after their application were evaluated. It has been shown that the introduction of solid plant particles increases the antioxidant properties of the emulsions and significantly improves emulsion stability and skin moisture after application.

Inhibition of miR-103a-3p suppresses lipopolysaccharide-induced sepsis and liver injury by regulating FBXW7 expression

Inflammation, apoptosis, and oxidative stress are involved in septic liver dysfunction. Herein, the role of miR‐103a‐3p/FBXW7 axis in lipopolysaccharides (LPS)‐induced septic liver injury was investigated in mice. Hematoxylin‐eosin staining was used to evaluate LPS‐induced liver injury. Quantitative real‐time polymerase chain reaction was performed to determine the expression of microRNA (miR) and messenger RNA, and western blot analysis was conducted to examine the protein levels. Dual‐luciferase reporter assay was used to confirm the binding between miR‐103a‐3p and FBXW7. Both annexin V‐fluoresceine isothiocyanate/propidium iodide staining and caspase‐3 activity were employed to determine cell apoptosis. First, miR‐103a‐3p was upregulated in the septic serum of mice and patients with sepsis, and miR‐103a‐3p was elevated in the septic liver of LPS‐induced mice. Then, interfering miR‐103a‐3p significantly decreased apoptosis by suppressing Bax expression and upregulating Bcl‐2 levels in LPS‐induced AML12 and LO2 cells, and septic liver of mice. Furthermore, inhibition of miR‐103a‐3p repressed LPS‐induced inflammation by downregulating the expression of tumor necrosis factor, interleukin 1β, and interleukin 6 in vitro and in vivo. Meanwhile, interfering miR‐103a‐3p obviously attenuated LPS‐induced overactivation of oxidation via promoting expression of antioxidative enzymes, including catalase, superoxide dismutase, and glutathione in vitro and in vivo. Moreover, FBXW7 was a target of miR‐103a‐3p, and overexpression of FBXW7 significantly ameliorated LPS‐induced septic liver injury in mice. Finally, knockdown of FBXW7 markedly reversed anti‐miR‐103a‐3p‐mediated suppression of septic liver injury in mice. In conclusion, interfering miR‐103a‐3p or overexpression of FBXW7 improved LPS‐induced septic liver injury by suppressing apoptosis, inflammation, and oxidative reaction.

Diversity of avenanthramide content in wild and cultivated oats

Background. Oat grains accumulate substantial amounts of various phenolic compounds that possess biological activity and have a potential to considerably increase health benefits of oats as a food. Avenanthramides (AVA) is an important group of these compounds due to their antioxidant, anti-itching, anti-inflammatory, antiproliferative activities.

Materials and methods. Using combined HPLC and LC-MS analyses, we provide the first comprehensive review of the total avenanthramide content and composition in cultivated and wild oats. The AVA content was measured in 32 wild and 120 cultivated oat accessions obtained from the global collection of the N.I. Vavilov Institute of Plant Genetic Resources (VIR), St. Petersburg, Russia.

Results and conclusion. The wild hexaploid A. sterilis L. had the highest total AVA content, reaching 1825 mg kg–1. Among cultivated accessions, naked oat cv. ‘Numbat’ (Australia) had the highest AVA content, 586 mg kg–1. The AVA composition exhibited a wide diversity among the analyzed samples. Accessions were identified where AVAs A, B and C, which are generally considered as major AVA, had a low percentage, and instead other AVAs prevailed. The AVA content in eight oat cultivars revealed significant annual changes in both the total AVA content and the proportions of individual AVAs. Using HPLC analyses, 22 distinguishable peaks in AVA extracts of oat seeds were detected and quantified. Several of these peaks, which have not been previously documented, presumably represent different AVAs. Further analyses are needed to detail these findings and to determine the specific AVA structures in oat grains.

Potential effects of rapeseed peptide Maillard reaction products on aging-related disorder attenuation and gut microbiota modulation in d-galactose induced aging mice

As a good flavor enhancer, rapeseed peptide Maillard reaction products (MRPs) were developed, and the effects of MRPs on d-galactose induced aging Kunming mice were investigated for 6 weeks with low (200 mg kg-1 day-1), medium (400 mg kg-1 day-1) and high (800 mg kg-1 day-1) doses. Compared with the natural aging group and d-galactose induced aging mice, the mice with MRP administration showed increases in body weight gain, food intake, organ indexes, feces color and urine fluorescence intensity. MRP intake significantly decreased the MDA content and elevated the activities of CAT, SOD and GSH-Px, and T-AOC in the serum and tissues of the liver, kidney and brain. Additionally, AChE activity was decreased in the brain, while Na+-K+ ATPase and Ca2+-Mg2+ ATPase activity increased in a dose-dependent manner, and decreasing levels of IL-1β, IL-6 and TNF-α were observed in the liver and kidney. Histopathological analysis suggested an attenuation of inflammatory cell infiltration in the liver and kidney without cell necrosis. High-throughput sequencing results revealed that the ratio of Firmicutes to Bacteroidetes increased in MRP groups, and the pathogenic bacteria were significantly inhibited, while some beneficial bacteria were significantly increased in the intestine. Overall, our results indicated that MRP consumption might have potential beneficial effects on postponing the aging process via reducing the oxidative stress and gut microflora modulation.

Overview of the Anticancer Profile of Avenanthramides from Oat

Cancer represents one of the leading causes of death worldwide. Progresses in treatment of cancer have continued at a rapid pace. However, undesirable side effects and drug resistance remain major challenges for therapeutic success. Natural products represent a valuable starting point to develop new anticancer strategies. Polyphenols, well-known as antioxidant, exert anticancer effects through the modulation of multiple pathways and mechanisms. Oat (Avena sativa L., Poaceae) is a unique source of avenanthramides (AVAs), a group of polyphenolic alkaloids, considered as its signature compounds. The present review aims to offer a comprehensive and critical perspective on the chemopreventive and chemotherapeutic potential of AVAs. AVAs prevent cancer mainly by blocking reactive species. Moreover, they exhibit potential therapeutic activity through the modulation of different pathways including the activation of apoptosis and senescence, the block of cell proliferation, and the inhibition of epithelial mesenchymal transition and metastatization. AVAs are promising chemopreventive and anticancer phytochemicals, which need further clinical trials and toxicological studies to define their efficacy in preventing and reducing the burden of cancer diseases.

Biological Activities, Health Benefits, and Therapeutic Properties of Avenanthramides: From Skin Protection to Prevention and Treatment of Cerebrovascular Diseases

Oat (Avena sativa) is a cereal known since antiquity as a useful grain with abundant nutritional and health benefits. It contains distinct molecular components with high antioxidant activity, such as tocopherols, tocotrienols, and flavanoids. In addition, it is a unique source of avenanthramides, phenolic amides containing anthranilic acid and hydroxycinnamic acid moieties, and endowed with major beneficial health properties because of their antioxidant, anti-inflammatory, and antiproliferative effects. In this review, we report on the biological activities of avenanthramides and their derivatives, including analogs produced in recombinant yeast, with a major focus on the therapeutic potential of these secondary metabolites in the treatment of aging-related human diseases. Moreover, we also present recent advances pointing to avenanthramides as interesting therapeutic candidates for the treatment of cerebral cavernous malformation (CCM) disease, a major cerebrovascular disorder affecting up to 0.5% of the human population. Finally, we highlight the potential of foodomics and redox proteomics approaches in outlining distinctive molecular pathways and redox protein modifications associated with avenanthramide bioactivities in promoting human health and contrasting the onset and progression of various pathologies. The paper is dedicated to the memory of Adelia Frison.

Sophocarpine Attenuates LPS-Induced Liver Injury and Improves Survival of Mice through Suppressing Oxidative Stress, Inflammation, and Apoptosis

Septic liver injury/failure that is mainly characterized by oxidative stress, inflammation, and apoptosis led to a great part of terminal liver pathology with limited effective intervention. Here, we used a lipopolysaccharide (LPS) stimulation model to simulate the septic liver injury and investigated the effect of sophocarpine on LPS-stimulated mice with endotoxemia. We found that sophocarpine increases the survival rate of mice and attenuates the LPS-induced liver injury, which is indicated by pathology and serum liver enzymes. Further research found that sophocarpine ameliorated hepatic oxidative stress indicators (H₂O₂, O₂^∙−, and NO) and enhanced the expression of antioxidant molecules such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). In addition, sophocarpine also attenuated regional and systematic inflammation and further reduced apoptosis of hepatocytes. Mechanistic evidence was also investigated in the present study as sophocarpine inhibited hepatic expression of the CYP2E/Nrf2 pathway during oxidative stress, inactivated p38/JNK cascade and NF-κB pathway, and, meanwhile, suppressed PI3K/AKT signaling that reduced apoptosis. Conclusively, the present study unveiled the protective role of sophocarpine in LPS-stimulated oxidative reaction, inflammation, and apoptosis by suppressing the CYP2E/Nrf2/ROS as well as PI3K/AKT pathways, suggesting its promising role in attenuating inflammation and liver injury of septic endotoxemia.

Silybum marianum oil attenuates hepatic steatosis and oxidative stress in high fat diet-fed mice

In the present study, the effects of Silybum marianum oil (SMO) on hepatic steatosis and oxidative stress were investigated during the development of nonalcoholic fatty liver disease (NAFLD) in high fat diet (HFD)-fed mice. The results showed that body weight, fat mass, and serum biochemical parameters such as triglyceride, free fatty acid, glucose and insulin were reduced by SMO treatment. Meanwhile, SMO decreased the histological injury of liver and the levels of hepatic triglyceride, cholesterol and free fatty acid in HFD-fed mice. SMO administration elevated the activities of superoxide dismutase (SOD) and catalase (CAT) and reduced the level of malondialdehyde (MDA) in the liver. Enzyme linked immunosorbent assay showed that SMO significantly decreased the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in HFD mice. Furthermore, the mRNA levels of sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase (FAS) and liver X receptor α (LXRα) were lower, but peroxisome proliferator-activated receptor α (PPARα) was higher in mice treated with SMO compared with the HFD group. The results indicated that SMO could play a certain protective role against HFD-induced NAFLD, and the protective effects might be associated with attenuating lipid accumulation, oxidative stress and inflammation, improving lipid metabolism.

High Levels of Avenanthramides in Oat-Based Diet Further Suppress High Fat Diet-Induced Atherosclerosis in Ldlr-/- Mice

Oats, in addition to cholesterol-lowering properties, contain unique antioxidants called avenanthramides (Avns), which inhibit both inflammatory cytokines and adhesion molecules in endothelial cells in culture. This study evaluated the effects of Avns of oats on atherosclerosis in Ldlr^-/- mice, one of the most commonly used atherosclerosis mouse models with their similar cholesterol distributions to humans. The Ldlr^-/- mice were fed a low fat, high fat, high fat containing regular oat brans with low levels of Avns (HFLA), or high fat containing regular oat brans with high levels of Avns (HFHA) diet. After 16 weeks of intervention, blood cholesterol and extent of aortic lesions were evaluated. We found that both oat-based diets reduced high fat diet-induced atheroma lesions in the aortic valve (p < 0.01). Furthermore, the effects of oat-based diets are more profound in HFHA mice than mice fed HFLA. Total plasma cholesterol levels were similarly reduced in both oat-supplemented mice. We concluded that oat bran diets reduce atheroma lesions and higher levels of Avns further reduce aortic lesions compared to regular oat bran. These preliminary in vivo data indicate that consumption of oats bran, with high Avns, has demonstrable beneficial effects on prevention of cardiovascular disease.

Whole grain oats, more than just a fiber: Role of unique phytochemicals

Oats are a good source of soluble dietary fiber, especially β-glucan, which has outstanding functional and nutritional properties. β-Glucan is considered to be the major active component of oats because of its cholesterol-lowering and antidiabetic effects. However, the nutritional benefits of oats appear to go beyond fiber to bioactive phytochemicals with strong antioxidant and anti-inflammatory effects. In this review, we summarize current knowledge on the chemistry, stability, bioavailability, and health effects of two unique phytochemicals in oats, avenanthramides, and avenacosides A and B. We conclude that studies on the beneficial effects of avenanthramides and avenacosides A and B are still in their infancy, and additional health benefits of these unique oat components may yet be identified.

Avenanthramides Prevent Osteoblast and Osteocyte Apoptosis and Induce Osteoclast Apoptosis in Vitro in an Nrf2-Independent Manner

Oats contain unique bioactive compounds known as avenanthramides (AVAs) with antioxidant properties. AVAs might enhance the endogenous antioxidant cellular response by activation of the transcription factor Nrf2. Accumulation of reactive oxygen species plays a critical role in many chronic and degenerative diseases, including osteoporosis. In this disease, there is an imbalance between bone formation by osteoblasts and bone resorption by osteoclasts, which is accompanied by increased osteoblast/osteocyte apoptosis and decreased osteoclast apoptosis. We investigated the ability of the synthethic AVAs 2c, 2f and 2p, to 1-regulate gene expression in bone cells, 2-affect the viability of osteoblasts, osteocytes and osteoclasts, and the generation of osteoclasts from their precursors, and 3-examine the potential involvement of the transcription factor Nrf2 in these actions. All doses of AVA 2c and 1 and 5 µM dose of 2p up-regulated collagen 1A expression. Lower doses of AVAs up-regulated OPG (osteoprotegerin) in OB-6 osteoblastic cells, whereas 100 μM dose of 2f and all concentrations of 2c down-regulated RANKL gene expression in MLO-Y4 osteocytic cells. AVAs did not affect apoptosis of OB-6 osteoblastic cells or MLO-Y4 osteocytic cells; however, they prevented apoptosis induced by the DNA topoisomerase inhibitor etoposide, the glucocorticoid dexamethasone, and hydrogen peroxide. AVAs prevented apoptosis of both wild type (WT) and Nrf2 Knockout (KO) osteoblasts, demonstrating that AVAs-induced survival does not require Nrf2 expression. Further, KO osteoclast precursors produced more mature osteoclasts than WT; and KO cultures exhibited less apoptotic osteoclasts than WT cultures. Although AVAs did not affect WT osteoclasts, AVA 2p reversed the low apoptosis of KO osteoclasts. These in vitro results demonstrate that AVAs regulate, in part, the function of osteoblasts and osteocytes and prevent osteoblast/osteocyte apoptosis and increase osteoclast apoptosis; further, these regulatory actions are independent of Nrf2.

Curcumin alleviates lipopolysaccharide induced sepsis and liver failure by suppression of oxidative stress-related inflammation via PI3K/AKT and NF-κB related signaling

In many liver disorders, oxidative stress-related inflammation and apoptosis are important pathogenic components, finally resulting in acute liver failure. Erythropoietin and its analogues are well known to influence the interaction between apoptosis and inflammation in brain and kidney. The study is to clarify the effect of curcumin, a natural plant phenolic food additive, on lipopolysaccharides (LPS)-induced acute liver injury of mice with endotoxemia and associated molecular mechanism from inflammation, apoptosis and oxidative stress levels. And curcumin, lowered serum cytokines, including Interleukin 1beta (IL-1β), Interleukin 6 (IL-6) and tumor necrosis factor (TNF-α), and improved liver apoptosis through suppressing phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway and inhibiting Cyclic AMP-responsive element-binding protein (CREB)/Caspase expression, and decreased oxidative stress-associated protein expression, mainly involving 2E1 isoform of cytochrome P450/nuclear factor E2-related factor 2/reactive oxygen species (CYP2E/Nrf2/ROS) signaling pathway, as well as liver nitric oxide (NO) production in LPS-induced mice. Moreover, curcumin regulated serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), accelerated liver antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GSH-px) levels, and inhibited activation of the mitogen-activated protein kinases/c-Jun NH2-terminal kinase (P38/JNK) cascade in the livers of LPS-induced rats. Thus, curcumin treatment attenuates LPS-induced PI3K/AKT and CYP2E/Nrf2/ROS signaling and liver injury. Strategies to inhibit inflammation and apoptosis signaling may provide alternatives to the current clinical approaches to improve oxidative responses of endotoxemia.

Protective Effect of Ginsenoside Rg1 on Hematopoietic Stem/Progenitor Cells through Attenuating Oxidative Stress and the Wnt/β-Catenin Signaling Pathway in a Mouse Model of d-Galactose-induced Aging

Stem cell senescence is an important and current hypothesis accounting for organismal aging, especially the hematopoietic stem cell (HSC). Ginsenoside Rg1 is the main active pharmaceutical ingredient of ginseng, which is a traditional Chinese medicine. This study explored the protective effect of ginsenoside Rg1 on Sca-1⁺ hematopoietic stem/progenitor cells (HSC/HPCs) in a mouse model of d-galactose-induced aging. The mimetic aging mouse model was induced by continuous injection of d-gal for 42 days, and the C57BL/6 mice were respectively treated with ginsenoside Rg1, Vitamin E or normal saline after 7 days of d-gal injection. Compared with those in the d-gal administration alone group, ginsenoside Rg1 protected Sca-1⁺ HSC/HPCs by decreasing SA-β-Gal and enhancing the colony forming unit-mixture (CFU-Mix), and adjusting oxidative stress indices like reactive oxygen species (ROS), total anti-oxidant (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-px) and malondialdehyde (MDA). In addition, ginsenoside Rg1 decreased β-catenin and c-Myc mRNA expression and enhanced the phosphorylation of GSK-3β. Moreover, ginsenoside Rg1 down-regulated advanced glycation end products (AGEs), 4-hydroxynonenal (4-HNE), phospho-histone H2A.X (r-H2A.X), 8-OHdG, p16(Ink4a), Rb, p21(Cip1/Waf1) and p53 in senescent Sca-1⁺ HSC/HPCs. Our findings indicated that ginsenoside Rg1 can improve the resistance of Sca-1⁺ HSC/HPCs in a mouse model of d-galactose-induced aging through the suppression of oxidative stress and excessive activation of the Wnt/β-catenin signaling pathway, and reduction of DNA damage response, p16(Ink4a)-Rb and p53-p21(Cip1/Waf1) signaling.

Chongcao-Shencha Attenuates Liver and Kidney Injury through Attenuating Oxidative Stress and Inflammatory Response in D-Galactose-Treated Mice

The Chongcao-Shencha (CCSC), a Chinese herbal compound formula, has been widely used as food material and medicine for enhancing physical strength. The present study investigated the possible effect of CCSC in alleviating the liver and kidney injury in D-galactose- (D-gal-) treated mice and the underlying mechanism. Mice were given a subcutaneous injection of D-gal (200 mg/kg) and orally administered CCSC (200, 400, and 800 mg/kg) daily for 8 weeks. Results indicated that CCSC increased the depressed body weight and organ index induced by D-gal, ameliorated the histological deterioration, and decreased the levels of ALT, AST, BUN, and CRE as compared with D-gal group. Furthermore, CCSC not only elevated the activities of antioxidant enzymes SOD, CAT, and GPx but also upregulated the mRNA expression of SOD1, CAT, and GPx1, while decreasing the MDA level in D-gal-treated mice. Results of western blotting analysis showed that CCSC significantly inhibited the upregulation of expression of nuclear factor kappa B (NF-κB) p65, p-p65, p-IκBα, COX2, and iNOS and inhibited the downregulation of IκBα protein expression caused by D-gal. This study demonstrated that CCSC could attenuate the liver and kidney injury in D-gal-treated mice, and the mechanism might be associated with attenuating oxidative stress and inflammatory response.

Protective effect of Artemisia annua L. extract against galactose-induced oxidative stress in mice

Artemisia annua L. (also called qinghao) has been well known as a source of antimalarial drug artemisinins. In addition, the herb was reported to have in vitro antioxidative activity. The present study investigated the protective effect of aqueous ethanol extract of Qinghao (AA extract) against D-galactose-induced oxidative stress in C57BL/6J mice. Feeding AA extract-containing diet lowered serum levels of malondialdehyde and 8-OH-dG that are biomarkers for lipid peroxidation and DNA damage, respectively. Furthermore, AA extract feeding enhanced the activity of NQO1, a typical antioxidant marker enzyme, in tissues such as kidney, stomach, small intestine, and large intestine. In conclusion, AA extract was found to have antioxidative activity in mouse model.

Silybum marianum oil attenuates oxidative stress and ameliorates mitochondrial dysfunction in mice treated with D-galactose

Background:

Silybum marianum has been used as herbal medicine for the treatment of liver disease, liver cirrhosis, and to prevent liver cancer in Europe and Asia since ancient times. Silybum marianum oil (SMO), a by-product of silymarin production, is rich in essential fatty acids, phospholipids, sterols, and vitamin E. However, it has not been very good development and use.

Objective:

In the present study, we used olive oil as a control to investigate the antioxidant and anti-aging effect of SMO in D-galactose (D-gal)-induced aging mice.

Materials and Methods:

D-gal was injected intraperitoneally (500 mg/kg body weight daily) for 7 weeks while SMO was simultaneously administered orally. The triglycerides (TRIG) and cholesterol (CHOL) levels were estimated in the serum. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), monoamine oxidase (MAO), malondialdehyde (MDA), caspase-3, and Bcl-2 were determined in the liver and brain. The activities of Na⁺-K⁺-adenosine triphosphatase (ATPase), Ca²⁺-Mg²⁺-ATPase, membrane potential (ΔΨm), and membrane fluidity of the liver mitochondrial were estimated.

Results:

SMO decreased levels of TRIG and CHOL in aging mice. SMO administration elevated the activities of SOD, GSH-Px, and T-AOC, which are suppressed by aging. The levels of MAO and MDA in the liver and brain were reduced by SMO administration in aging mice. Enzyme linked immunosorbent assay showed that SMO significantly decreased the concentration of caspase-3 and improved the activity of Bcl-2 in the liver and brain of aging mice. Furthermore, SMO significantly attenuated the D-gal induced liver mitochondrial dysfunction by improving the activities of Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase, membrane potential (ΔΨm), and membrane fluidity.

Conclusion:

These results indicate that SMO effectively attenuated oxidative damage and improved apoptosis related factors as well as liver mitochondrial dysfunction in aging mice.

Effect of oat intake on glycaemic control and insulin sensitivity: a meta-analysis of randomised controlled trials

The present meta-analysis of randomised controlled trials (RCT) aimed to investigate the effect of oat intake on glycaemic control and insulin sensitivity. A literature search was carried out in PubMed, ScienceDirect Online and The Cochrane Library (up to October 2013) for RCT that assessed the effect of oat intake on glucose control and insulin sensitivity. A total of fifteen articles with 673 subjects met the inclusion criteria. A random-effects model was used when the overall pooled studies exhibited significant heterogeneity. Otherwise, a fixed-effects model was used. Compared with controls, oat intake significantly reduced the concentrations of fasting insulin by - 6·29 (95 % CI - 12·32, - 0·27) pmol/l (P= 0·04) and the values of glucose AUC (GAUC; 0-120 min) by - 30·23 (95 % CI - 43·65, - 16·81) min × mmol/l (P< 0·0001). There was a slight decrease in fasting glucose concentrations, glycated Hb concentrations and homeostatic model assessment-insulin resistance values in subjects who consumed oats, but the difference was not significant. In conclusion, oat intake significantly lowers fasting insulin concentrations and GAUC values. To further investigate the effect of oat intake on fasting glucose concentrations, additional long-term and high-quality RCT with a parallel design are required.

Protective effect of oat bran extracts on human dermal fibroblast injury induced by hydrogen peroxide

Oat contains different components that possess antioxidant properties; no study to date has addressed the antioxidant effect of the extract of oat bran on the cellular level. Therefore, the present study focuses on the investigation of the protective effect of oat bran extract by enzymatic hydrolysates on human dermal fibroblast injury induced by hydrogen peroxide (H(2)O(2)). Kjeldahl determination, phenol-sulfuric acid method, and high-performance liquid chromatography (HPLC) analysis indicated that the enzymatic products of oat bran contain a protein amount of 71.93%, of which 97.43% are peptides with a molecular range from 438.56 to 1301.01 Da. Assays for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity indicate that oat peptide-rich extract has a direct and concentration-dependent antioxidant activity. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay and the TdT-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay for apoptosis showed that administration of H(2)O(2) in human dermal fibroblasts caused cell damage and apoptosis. Pre-incubation of human dermal fibroblasts with the Oatp for 24 h markedly inhibited human dermal fibroblast injury induced by H(2)O(2), but application oat peptides with H(2)O(2) at same time did not. Pre-treatment of human dermal fibroblasts with Oatp significantly reversed the H(2)O(2)-induced decrease of superoxide dismutase (SOD) and the inhibition of malondialdehyde (MDA). The results demonstrate that oat peptides possess antioxidant activity and are effective against H(2)O(2)-induced human dermal fibroblast injury by the enhanced activity of SOD and decrease in MDA level. Our results suggest that oat bran will have the potential to be further explored as an antioxidant functional food in the prevention of aging-related skin injury.

Production of hydroxycinnamoyl anthranilates from glucose in Escherichia coli

BACKGROUND

Oats contain hydroxycinnamoyl anthranilates, also named avenanthramides (Avn), which have beneficial health properties because of their antioxidant, anti-inflammatory, and antiproliferative effects. The microbial production of hydroxycinnamoyl anthranilates is an eco-friendly alternative to chemical synthesis or purification from plant sources. We recently demonstrated in yeast (Saccharomyces cerevisiae) that coexpression of 4-coumarate: CoA ligase (4CL) from Arabidopsis thaliana and hydroxycinnamoyl/benzoyl-CoA/anthranilate N-hydroxycinnamoyl/benzoyltransferase (HCBT) from Dianthus caryophyllusenabled the biological production of several cinnamoyl anthranilates upon feeding with anthranilate and various cinnamates. Using engineering strategies to overproduce anthranilate and hydroxycinnamates, we describe here an entire pathway for the microbial synthesis of two Avns from glucose in Escherichia coli.

RESULTS

We first showed that coexpression of HCBT and Nt4CL1 from tobacco in the E. coli anthranilate-accumulating strain W3110 trpD9923 allowed the production of Avn D [N-(4'-hydroxycinnamoyl)-anthranilic acid] and Avn F [N-(3',4'-dihydroxycinnamoyl)-anthranilic acid] upon feeding with p-coumarate and caffeate, respectively. Moreover, additional expression in this strain of a tyrosine ammonia-lyase from Rhodotorula glutinis (RgTAL) led to the conversion of endogenous tyrosine into p-coumarate and resulted in the production of Avn D from glucose. Second, a 135-fold improvement in Avn D titer was achieved by boosting tyrosine production using two plasmids that express the eleven genes necessary for tyrosine synthesis from erythrose 4-phosphate and phosphoenolpyruvate. Finally, expression of either the p-coumarate 3-hydroxylase Sam5 from Saccharothrix espanensis or the hydroxylase complex HpaBC from E. coli resulted in the endogenous production of caffeate and biosynthesis of Avn F.

CONCLUSION

We established a biosynthetic pathway for the microbial production of valuable hydroxycinnamoyl anthranilates from an inexpensive carbon source. The proposed pathway will serve as a platform for further engineering toward economical and sustainable bioproduction of these pharmaceuticals and other related aromatic compounds.

Effect of Colla corii asini (E'jiao) on D-galactose induced aging mice

Colla corii asini (E'jiao), donkey-hide gelatin prepared by stewing and concentrating from Equus asinus L. donkey hide, is a traditional Chinese medicine preparation widely used in clinical hematic antanemic therapy in China. The aim of the present study was to investigate potential anti-aging effect of Colla corii asini and explore related mechanisms in D-galactose (gal) induced aging model mice. The mice were artificially induced aging by subcutaneously injection with D-gal at the dose of 100 mg/kg·d for 8 weeks. Colla corii asini was simultaneously treated to them once daily by intragastric gavage. Appetite, mental condition, body weight, and organ index were observed. Activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), as well as levels of malondialdehyde (MDA) in serum, brain, and liver were determined by according assay kits. Western blotting analysis was used to detect p16 and p21 expression. Results indicated that Colla corii asini could improve appetite, mental condition, body weight, and organ condition of model mice, improve SOD, CAT, and GSH-Px activities, reduce MDA levels, and modulate age-related genes expression in D-gal induced mice. Therefore, Colla corii asini may have effect to suppress the aging process through enhancing antioxidant activity, scavenging free radicals, and modulating aging-related gene expression.

Phytochemicals attenuating aberrant activation of β-catenin in cancer cells

Phytochemicals are a rich source of chemoprevention agents but their effects on modulating the Wnt/β-catenin signaling pathway have remained largely uninvestigated. Aberrantly activated Wnt signaling can result in the abnormal stabilization of β-catenin, a key causative step in a broad spectrum of cancers. Here we report the modulation of lithium chloride-activated canonical Wnt/β-catenin signaling by phytochemicals that have antioxidant, anti-inflammatory or chemopreventive properties. The compounds were first screened with a cervical cancer-derived stable Wnt signaling reporter HeLa cell line. Positive hits were subsequently evaluated for β-catenin degradation, suppression of β-catenin nuclear localization and down-regulation of downstream oncogenic targets of Wnt/β-catenin pathway. Our study shows a novel degradation path of β-catenin protein in HeLa cells by Avenanthramide 2p (a polyphenol) and Triptolide (a diterpene triepoxide), respectively from oats and a Chinese medicinal plant. The findings present Avenanthramide 2p as a potential chemopreventive dietary compound that merits further study using in vivo models of cancers; they also provide a new perspective on the mechanism of action of Triptolide.

Antioxidant and anticholinesterase effects of frequently consumed cereal grains using in vitro test models

The ethyl acetate and ethanol extracts obtained from eight varieties (Faikbey, Y-1779, CI-8357, Cheokota, Seydişehir, Y-330, Sivas and YVD-18) of oat (Avena sativa L.), one variety (Larende) of barley (Hordeum vulgare L.), one variety (Tatlicak 97) of triticale (Triticale sp.) and one rye variety (Aslim 95) (Secale cereale L.) were investigated for their antioxidant effects in seven test systems. Anticholinesterase activity of the extracts was examined by enzyme-linked immunosorbent assay (ELISA) microplate reader. Total phenol and flavonoid contents were calculated using Folin Ciocalteau and AlCl₃ reagents, respectively. All of the extracts were ineffective in cholinesterase inhibition assays and had weak-to-moderate activity in antioxidant assays. The extracts exerted better activity in iron-chelation capacity ranging between 43.17 ± 2.04 and 62.97 ± 1.29%. Triticale extracts showed higher activity in reducing power experiments. A notable difference in the results of the antioxidant activity assays was observed among the oat varieties.

Chemical characterization of a procyanidin-rich extract from sorghum bran and its effect on oxidative stress and tumor inhibition in vivo

The present study was to characterize a procyanidin-rich extract (PARE) from sorghum ( Sorghum bicolor (L.) Moench) bran and assess its biological activities. The procyanidin oligomers were separated and identified by normal-phase HPLC equipped with fluorescence (FLD) and mass spectrometry (MS) detectors. In addition, the effects of PARE on oxidative stress in mice induced by D-galactose as well as tumor inhibition in C57BL/6J mice bearing Lewis lung cancer were investigated. Administration of D-galactose significantly (p < 0.05) lowered the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). This was accompanied by a significant (p < 0.05) increase in malondialdehyde (MDA) levels in both liver and serum. Administration of PARE (150 mg/kg) significantly (p < 0.05) reversed the d-galactose-induced oxidative stress by enhancing the activities of antioxidant enzymes. Furthermore, PARE administration inhibited tumor growth and metastasis formation by suppressing vascular endothelial growth factor (VEGF) production. The results suggested that PARE had antioxidant and antitumor activities.