β-Carotene and lutein inhibit hydrogen peroxide-induced activation of NF-κB and IL-8 expression in gastric epithelial AGS cells

The potential modulation of gut microbiota and oxidative stress by dietary carotenoid pigments

Gut microbiota plays a crucial role in regulating the response to immune checkpoint therapy, therefore modulation of the microbiome with bioactive molecules like carotenoids might be a very effective strategy to reduce the risk of chronic diseases. This review highlights the bio-functional effect of carotenoids on Gut Microbiota modulation based on a bibliographic search of the different databases. The methodology given in the preferred reporting items for systematic reviews and meta-analyses (PRISMA) has been employed for developing this review using papers published over two decades considering keywords related to carotenoids and gut microbiota. Moreover, studies related to the health-promoting properties of carotenoids and their utilization in the modulation of gut microbiota have been presented. Results showed that there can be quantitative changes in intestinal bacteria as a function of the type of carotenoid. Due to the dependency on several factors, gut microbiota continues to be a broad and complex study subject. Carotenoids are promising in the modulation of Gut Microbiota, which favored the appearance of beneficial bacteria, resulting in the protection of villi and intestinal permeability. In conclusion, it can be stated that carotenoids may help to protect the integrity of the intestinal epithelium from pathogens and activate immune cells.

Dietary intake and serum concentrations of vitamin A and vitamin E and pre-eclampsia risk in Chinese pregnant women: A matched case-control study

Background

Many studies have suggested that the serum concentrations of vitamin A (VA) and vitamin E (VE) influence preeclampsia (PE) risk in pregnant women. However, few studies have assessed whether dietary intake and serum concentrations of VA and VE are correlated with PE risk.

Methods

A 1:1 matched case-control study was conducted to explore the association between the dietary intake and serum concentrations of VA and VE and the risk of PE in pregnant Chinese women. A total of 440 pregnant women with PE and 440 control pregnant women were included in the study. Dietary information was obtained using a 78-item semi-quantitative food frequency questionnaire. Serum concentrations of VA and VE were measured by liquid chromatography-tandem mass spectrometry.

Results

Compared with the lowest quartile, the multivariate-adjusted odds ratios [95% confidence interval (CI)] of the highest quartiles were 0.62 (95% CI: 0.40-0.96, P trend = 0.02) for VA, 0.51 (95% CI: 0.33–0.80, P trend =0.002) for β-carotene, and 0.70 (95% CI: 0.45–1.08, P trend = 0.029) for retinol. Additionally, for serum VA and VE concentrations, the multivariate-adjusted odds ratios (95% CI) were 2.75 (95% CI: 1.24–6.13, P trend = 0.002) and 11.97 (95% CI: 4.01–35.77, P trend < 0.001), respectively. No significant association was seen between VE intake and PE risk.

Conclusions

Dietary VA intake was negatively correlated with PE risk, and serum VA and VE concentrations were positively correlated with PE risk among pregnant Chinese women.

Changes in the Expression Profile of Pyroptosis-Related Genes in Senescent Retinal Pigment Epithelial Cells after Lutein Treatment

Retinal pigment epithelium (RPE) is a specialized structure essential for proper vision, which is constantly exposed to oxidative damage. With aging, this damage accumulates within the RPE cells, causing various diseases, including age-related macular degeneration (AMD). Numerous antioxidant substances are used to prevent this process in humans, including lutein. This study aims to determine the differences in the expression patterns of pyroptosis genes in senescent human retinal pigment epithelial cell line ARPE-19 exposed to lutein. Changes in the expression of pyroptosis-related genes were assessed by oligonucleotide microarrays, and the results were validated by real-time RT-qPCR. The microarray analysis showed seven transcripts were differentially expressed both in the H₂O₂-treated cells versus the controls and in the lutein/H₂O₂-treated cells compared to the H₂O₂-treated cells (FC > 2.0). Depending on the used lutein, H₂O₂, or co-treatment of ARPE-19 cells, statistically significant differences in the expression of TXNIP, CXCL8, BAX, and CASP1 genes were confirmed by the RT-qPCR (p < 0.05). A STRING database analysis showed that the proteins encoded by the analyzed genes form a strong interaction network (p < 0.001). These data indicate that lutein modulates the expression level of pyroptosis-related genes, which may be useful for the development of new methods preventing pyroptosis pathway activation in the future.

Anticancer applications of phytochemicals in gastric cancer: Effects and molecular mechanism

Gastric cancer (GC) is the fourth most common malignant cancer and is a life-threatening disease worldwide. Phytochemicals have been shown to be a rational, safe, non-toxic, and very promising approach to the prevention and treatment of cancer. It has been found that phytochemicals have protective effects against GC through inhibiting cell proliferation, inducing apoptosis and autophagy, suppressing cell invasion and migration, anti-angiogenesis, inhibit Helicobacter pylori infection, regulating the microenvironment. In recent years, the role of phytochemicals in the occurrence, development, drug resistance and prognosis of GC has attracted more and more attention. In order to better understand the relationship between phytochemicals and gastric cancer, we briefly summarize the roles and functions of phytochemicals in GC tumorigenesis, development and prognosis. This review will probably help guide the public to prevent the occurrence and development of GC through phytochemicals, and develop functional foods or drugs for the prevention and treatment of gastric cancer.

Low Xanthophylls, Retinol, Lycopene, and Tocopherols in Grey and White Matter of Brains with Alzheimer's Disease

BACKGROUND

Oxidative stress contributes to pathogenesis and progression of Alzheimer's disease (AD). Higher levels of the dietary antioxidants- carotenoids and tocopherols- are associated with better cognitive functions and lower risk for AD, and lower levels of multiple carotenoids are found in serum and plasma of patients with AD. Although brains donated by individuals with mild cognitive impairment had significantly lower levels of lutein and beta-carotene, previous investigators found no significant difference in carotenoid levels of brains with AD and cognitively normal brains.

OBJECTIVE

This study tested the hypothesis that micronutrients are significantly lower in donor brains with AD than in healthy elderly brains.

METHODS

Samples of donor brains with confirmed AD or verified health were dissected into grey and white matter, extracted with organic solvents and analyzed by HPLC.

RESULTS

AD brains had significantly lower levels of lutein, zeaxanthin, anhydrolutein, retinol, lycopene, and alpha-tocopherol, and significantly increased levels of XMiAD, an unidentified xanthophyll metabolite. No meso-zeaxanthin was detected. The overlapping protective roles of xanthophylls, carotenes, α- and γ-tocopherol are discussed.

CONCLUSION

Brains with AD had substantially lower concentrations of some, but not all, xanthophylls, carotenes, and tocopherols, and several-fold higher concentrations of an unidentified xanthophyll metabolite increased in AD (XMiAD).

Molecular mechanisms underlying the action of carcinogens in gastric cancer with a glimpse into targeted therapy

BACKGROUND

Gastric cancer imposes a substantial global health burden despite its overall incidence decrease. A broad spectrum of inherited, environmental and infectious factors contributes to the development of gastric cancer. A profound understanding of the molecular underpinnings of gastric cancer has lagged compared to several other tumors with similar incidence and morbidity rates, owing to our limited knowledge of the role of carcinogens in this malignancy. The International Agency for Research on Cancer (IARC) has classified gastric carcinogenic agents into four groups based on scientific evidence from human and experimental animal studies. This review aims to explore the potential comprehensive molecular and biological impacts of carcinogens on gastric cancer development and their interactions and interferences with various cellular signaling pathways.

CONCLUSIONS

In this review, we highlight recent clinical trial data reported in the literature dealing with different ways to target various carcinogens in gastric cancer. Moreover, we touch upon other multidisciplinary therapeutic approaches such as surgery, adjuvant and neoadjuvant chemotherapy. Rational clinical trials focusing on identifying suitable patient populations are imperative to the success of single-agent therapeutics. Novel insights regarding signaling pathways that regulate gastric cancer can potentially improve treatment responses to targeted therapy alone or in combination with other/conventional treatments. Preventive strategies such as control of H. pylori infection through eradication or immunization as well as dietary habit and lifestyle changes may reduce the incidence of this multifactorial disease, especially in high prevalence areas. Further in-depth understanding of the molecular mechanisms involved in the role of carcinogenic agents in gastric cancer development may offer valuable information and update state-of-the-art resources for physicians and researchers to explore novel ways to combat this disease, from bench to bedside. A schematic outlining of the interaction between gastric carcinogenic agents and intracellular pathways in gastric cancer H. pylori stimulates multiple intracellular pathways, including PI3K/AKT, NF-κB, Wnt, Shh, Ras/Raf, c-MET, and JAK/STAT, leading to epithelial cell proliferation and differentiation, apoptosis, survival, motility, and inflammatory cytokine release. EBV can stimulate intracellular pathways such as the PI3K/Akt, RAS/RAF, JAK/STAT, Notch, TGF-β, and NF-κB, leading to cell survival and motility, proliferation, invasion, metastasis, and the transcription of anti-apoptotic genes and pro-inflammatory cytokines. Nicotine and alcohol can lead to angiogenesis, metastasis, survival, proliferation, pro-inflammatory, migration, and chemotactic by stimulating various intracellular signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, ROS, and JAK/STAT. Processed meat contains numerous carcinogenic compounds that affect multiple intracellular pathways such as sGC/cGMP, p38 MAPK, ERK, and PI3K/AKT, leading to anti-apoptosis, angiogenesis, metastasis, inflammatory responses, proliferation, and invasion. Lead compounds may interact with multiple signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, DNA methylation-dependent, and epigenetic-dependent, leading to tumorigenesis, carcinogenesis, malignancy, angiogenesis, DNA hypermethylation, cell survival, and cell proliferation. Stimulating signaling pathways such as PI3K/Akt, RAS/RAF, JAK/STAT, WNT, TGF-β, EGF, FGFR2, and E-cadherin through UV ionizing radiation leads to cell survival, proliferation, and immortalization in gastric cancer. The consequence of PI3K/AKT, NF-κB, Ras/Raf, ROS, JAK/STAT, and WNT signaling stimulation by the carcinogenic component of Pickled vegetables and salted fish is the Warburg effect, tumorigenesis, angiogenesis, proliferation, inflammatory response, and migration.

The Interplay of Oxidative Stress and ROS Scavenging: Antioxidants as a Therapeutic Potential in Sepsis

Oxidative stress resulting from the disproportion of oxidants and antioxidants contributes to both physiological and pathological conditions in sepsis. To combat this, the antioxidant defense system comes into the picture, which contributes to limiting the amount of reactive oxygen species (ROS) leading to the reduction of oxidative stress. However, a strong relationship has been found between scavengers of ROS and antioxidants in preclinical in vitro and in vivo models. ROS is widely believed to cause human pathology most specifically in sepsis, where a small increase in ROS levels activates signaling pathways to initiate biological processes. An inclusive understanding of the effects of ROS scavenging in cellular antioxidant signaling is essentially lacking in sepsis. This review compiles the mechanisms of ROS scavenging as well as oxidative damage in sepsis, as well as antioxidants as a potent therapeutic. Direct interaction between ROS and cellular pathways greatly affects sepsis, but such interaction does not provide the explanation behind diverse biological outcomes. Animal models of sepsis and a number of clinical trials with septic patients exploring the efficiency of antioxidants in sepsis are reviewed. In line with this, both enzymatic and non-enzymatic antioxidants were effective, and results from recent studies are promising. The usage of these potent antioxidants in sepsis patients would greatly impact the field of medicine.

Association of dietary and plasma carotenoids with urinary F2-isoprostanes

PURPOSE

Carotenoids may protect against chronic diseases including cancer and cardiometabolic disease by mitigating oxidative stress and/or inflammation. We cross-sectionally evaluated associations between carotenoids and biomarkers of oxidative stress or inflammation.

METHODS

From 2003 to 2009, the Sister Study enrolled 50,884 breast cancer-free US women aged 35-74. Post-menopausal participants (n = 512) were randomly sampled to measure carotenoids and biomarkers of oxidative stress. Dietary carotenoid consumption was assessed using a validated 110-item Block 1998 food frequency questionnaire; use of β-carotene-containing supplements was also assessed. Plasma carotenoids were quantified, adjusting for batch. Urinary markers of lipid peroxidation, 8-iso-prostaglandin F_2α (8-iso-PGF_2α) and its metabolite (8-iso-PGF_2α-M) were also measured. Since the biomarker 8-iso-PGF_2α can reflect both oxidative stress and inflammation, we used a modeled 8-iso-PGF_2α to prostaglandin F_2α ratio approach to distinguish effects reflecting oxidative stress versus inflammation. Multivariable linear regression was used to assess the associations of dietary and plasma carotenoids with the estimated biomarker concentrations.

RESULTS

Total plasma carotenoids were inversely associated with 8-iso-PGF_2α-M concentrations (P for trend across quartiles = 0.009). Inverse trends associations were also seen for α-carotene and β-carotene. In contrast, lutein/zeaxanthin showed associations with both 8-iso-PGF_2α and 8-iso-PGF_2α-M concentrations. The inverse association for total carotenoids appeared to be specific for oxidative stress (chemical 8-iso-PGF_2α; P_{highest vs. lowest quartile} = 0.04 and P for trend across quartiles = 0.02). The pattern was similar for α-carotene. However, lutein/zeaxanthin tended to have a stronger association with enzymatic 8-iso-PGF_2α, suggesting an additional anti-inflammatory effect. Supplemental β-carotene was inversely associated with both 8-iso-PGF_2α and 8-iso-PGF_2α-M concentrations, as well as with both chemical and enzymatic 8-iso-PGF_2α. Dietary carotenoids were not associated with either biomarker.

CONCLUSION

Plasma carotenoids and supplemental β-carotene were associated with lower concentrations of 8-iso-PGF_2α metabolite. Plasma carotenoids associations may reflect antioxidant effects.

Effective inhibition of adipogenesis-mediated inflammation by a macular carotenoid, lutein in vitro

An absolute interlinks between inflammation and obesity with scarce investigations on the role of lutein in inflammation-induced obesity motivated us to explore the protective mechanism of lutein on adipogenesis-mediated inflammation in vitro by culturing RAW264.7 macrophages in adipocyte conditioned medium. The RAW264 macrophage cells were cultured with adipocyte-conditioned media, and the potency of lutein on the expression of adipocyte inflammation-associated protein markers (IL-1β, MCP-1, TNF-α, IL-6, NF-κB, and IKKα/β) were analyzed by western blotting. The data revealed that lutein effectively reduces the protein levels of major inflammatory markers such as NF-κB, IL-1β, MCP-1, and TNF-α in differentiated adipocytes. Interestingly, lutein hampered inflammation in the RAW264 cells that were cultured in adipocyte-conditioned media by lowering the protein expression of IL-1β, MCP-1, and TNF-α. The blockage of inflammation by lutein in both differentiated adipocytes, and adipogenesis-induced macrophages is associated with suppression of IKK α/β phosphorylation. These data suggest that lutein potentially alters adipocyte differentiation-mediated inflammation by regulating the NF-κB signaling pathway. Thus, lutein could be utilized as a potent nutraceutical agent in the management of obesity and associated inflammation. PRACTICAL APPLICATIONS: Lutein isolated from a dietary source exhibited an inhibitory effect in adipogenesis-induced inflammations. The findings of this study authenticate the diversified prospective of lutein in regulating obesity and other inflammation-related diseases. Thus, it is understood that continuous intake of lutein-rich food or dietary intervention of lutein may reduce the risk of developing obesity.

Monoamine Oxidase-B Inhibitor Reduction in Pro-Inflammatory Cytokines Mediated by Inhibition of cAMP-PKA/EPAC Signaling

Mucosal epithelial cell integrity is an important component of innate immunity and it protects the host from an environment rich in microorganisms. Virulence factors from Gram-negative bacteria [e.g. lipopolysaccharide (LPS)] induce significant pro-inflammatory cytokine expression. Monoamine oxidase (MAO) inhibitors reduce cytokine expression in a variety of inflammatory models and may therefore have therapeutic potential for a number of inflammatory diseases. We tested the anti-inflammatory therapeutic potential of a recently developed reversible MAO-B inhibitor (RG0216) with reduced transport across the blood–brain barrier. In an epithelial cell culture model, RG0216 significantly decreased LPS-induced interleukin (IL)-6 and IL-1β gene and protein expression and was as effective as equimolar concentrations of deprenyl (an existing irreversible MAO-B inhibitor). Hydrogen peroxide and modulating dopamine receptor signaling had no effect on cytokine expression. We showed that LPS-induced expression of IL-6 and IL-1β was cAMP dependent, that IL-6 and IL-1β expression were induced by direct cAMP activation (forskolin) and that RG0216 and deprenyl effectively reduced cAMP-mediated cytokine expression. Targeted protein kinase A (PKA) and Exchange Protein Activated by cAMP (EPAC) activation regulated IL-6 and IL-1β expression, albeit in different ways, but both cytokines were effectively decreased with RG0216. RG0216 reduction of LPS-induced cytokine expression occurred by acting downstream of the cAMP-PKA/EPAC signaling cascade. This represents a novel mechanism by which MAO-B selective inhibitors regulate LPS-induced IL-6 and IL-1β expression.

Neoxanthin prevents H2O2-induced cytotoxicity in HepG2 cells by activating endogenous antioxidant signals and suppressing apoptosis signals

BACKGROUND

The liver has a solid inbuilt antioxidant defense system to regulate oxidative stress. However, exposure to an excessive level of ROS causes liver injury. This study examined the cytoprotective effect of neoxanthin, a xanthophyll antioxidant molecule isolated from Solanum trilobatum in stress-induced HepG2 cells.

METHODS AND RESULTS

The cytotoxic effect of H₂O₂ and cytoprotective potential of β-carotene, lutein, and neoxanthin was analyzed by WST-1 assay. The intracellular ROS level and mitochondrial membrane potential (MMP) were measured using DCFH-DA (2', 7'-dichlorofluorescin diacetate) and JC-10 MMP assay. The expression of anti-oxidant and apoptotic markers was measured by western blot analysis. Neoxanthin pretreatment exhibited better protection than β-carotene and lutein against cell death caused by H₂O₂. It significantly arrested H₂O₂-mediated elevation of intracellular ROS levels and protected MMP. The intracellular antioxidant enzymes HO-1 and SOD-2 were upregulated by neoxanthin pretreatment. Neoxanthin also activated the protein expression of redox-sensitive transactivation factors, Nrf2 and NF-kB. The cytoprotective effect of neoxanthin was associated with increased expression of the anti-apoptotic protein, Bcl-2 and decreased pro-apoptotic protein Bax.

CONCLUSIONS

For the first time, our results demonstrate that neoxanthin offers adequate protection against stress-mediated cytotoxicity in hepatocytes by activating the intracellular antioxidant defense system and blocking apoptosis.

Beta-carotene and its protective effect on gastric cancer

Beta-carotene is an important natural pigment that is very beneficial to human health. It is widely found in vegetables and fruits. The three main functions are antioxidant effects, cell gap junction-related functions and immune-related functions. Because of its diverse functions, beta-carotene is believed to prevent and treat many chronic diseases. Gastric cancer is one of the most important diseases it can treat. Gastric cancer is a type of cancer with a high incidence. Its etiology varies, and the pathogenesis is complex. Gastric cancer seriously affects human health. The role of beta-carotene, a natural nutrient, in gastric cancer has been explored by many researchers, including molecular mechanisms and epidemiological studies. Molecular studies have mainly focused on oxidative stress, cell cycle, signal transduction pathways and immune-related mechanisms of beta-carotene in gastric cancer. Many epidemiological surveys and cohort studies of patients with gastric cancer have been conducted, and the results of these epidemiological studies vary due to the use of different research methods and analysis of different regions. This paper will summarize the results of these studies, mainly in terms of molecular mechanisms and epidemiological research results, which will provide a systematic basis for future studies of the treatment and prognosis of gastric cancer. This paper will help researchers identify new research directions.

Mechanistic aspects of carotenoid health benefits - where are we now?

Dietary intake and tissue levels of carotenoids have been associated with a reduced risk of several chronic diseases, including cardiovascular diseases, type 2 diabetes, obesity, brain-related diseases and some types of cancer. However, intervention trials with isolated carotenoid supplements have mostly failed to confirm the postulated health benefits. It has thereby been speculated that dosing, matrix and synergistic effects, as well as underlying health and the individual nutritional status plus genetic background do play a role. It appears that our knowledge on carotenoid-mediated health benefits may still be incomplete, as the underlying mechanisms of action are poorly understood in relation to human relevance. Antioxidant mechanisms - direct or via transcription factors such as NRF2 and NF-κB - and activation of nuclear hormone receptor pathways such as of RAR, RXR or also PPARs, via carotenoid metabolites, are the basic principles which we try to connect with carotenoid-transmitted health benefits as exemplified with described common diseases including obesity/diabetes and cancer. Depending on the targeted diseases, single or multiple mechanisms of actions may play a role. In this review and position paper, we try to highlight our present knowledge on carotenoid metabolism and mechanisms translatable into health benefits related to several chronic diseases.

Monoamine Oxidase Inhibitors: A Review of Their Anti-Inflammatory Therapeutic Potential and Mechanisms of Action

Chronic inflammatory diseases are debilitating, affect patients' quality of life, and are a significant financial burden on health care. Inflammation is regulated by pro-inflammatory cytokines and chemokines that are expressed by immune and non-immune cells, and their expression is highly controlled, both spatially and temporally. Their dysregulation is a hallmark of chronic inflammatory and autoimmune diseases. Significant evidence supports that monoamine oxidase (MAO) inhibitor drugs have anti-inflammatory effects. MAO inhibitors are principally prescribed for the management of a variety of central nervous system (CNS)-associated diseases such as depression, Alzheimer's, and Parkinson's; however, they also have anti-inflammatory effects in the CNS and a variety of non-CNS tissues. To bolster support for their development as anti-inflammatories, it is critical to elucidate their mechanism(s) of action. MAO inhibitors decrease the generation of end products such as hydrogen peroxide, aldehyde, and ammonium. They also inhibit biogenic amine degradation, and this increases cellular and pericellular catecholamines in a variety of immune and some non-immune cells. This decrease in end product metabolites and increase in catecholamines can play a significant role in the anti-inflammatory effects of MAO inhibitors. This review examines MAO inhibitor effects on inflammation in a variety of in vitro and in vivo CNS and non-CNS disease models, as well as their anti-inflammatory mechanism(s) of action.

Dietary Cameroonian Plants Exhibit Anti-Inflammatory Activity in Human Gastric Epithelial Cells

In Cameroon, local plants are traditionally used as remedies for a variety of ailments. In this regard, several papers report health benefits of Cameroonian spices, which include antioxidant and anti-microbial properties, whereas gastric anti-inflammatory activities have never been previously considered. The present study investigates the antioxidant and anti-inflammatory activities of hydro-alcoholic extracts of eleven Cameroonian spices in gastric epithelial cells (AGS and GES-1 cells). The extracts showed antioxidant properties in a cell-free system and reduced H₂O₂-induced ROS generation in gastric epithelial cells. After preliminary screening on TNFα-induced NF-κB driven transcription, six extracts from Xylopia parviflora, Xylopia aethiopica, Tetrapleura tetraptera, Dichrostachys glomerata, Aframomum melegueta, and Aframomum citratum were selected for further studies focusing on the anti-inflammatory activity. The extracts reduced the expression of some NF-κB-dependent pro-inflammatory mediators strictly involved in the gastric inflammatory process, such as IL-8, IL-6, and enzymes such as PTGS2 (COX-2), without affecting PTGS1 (COX-1). In conclusion, the selected extracts decreased pro-inflammatory markers by inhibiting the NF-κB signaling in gastric cells, justifying, in part, the traditional use of these spices. Other molecular mechanisms cannot be excluded, and further studies are needed to better clarify their biological activities at the gastric level.

Targeting the tumor immune microenvironment with "nutraceuticals": From bench to clinical trials

The occurrence of immune effector cells in the tissue microenvironment during neoplastic progression is critical in determining tumor growth outcomes. On the other hand, tumors may also avoid immune system-mediated elimination by recruiting immunosuppressive leukocytes and soluble factors, which coordinate a tumor microenvironment that counteracts the efficiency of the antitumor immune response. Checkpoint inhibitor therapy results have indicated a way forward via activation of the immune system against cancer. Widespread evidence has shown that different compounds in foods, when administered as purified substances, can act as immunomodulators in humans and animals. Although there is no universally accepted definition of nutraceuticals, the term identifies a wide category of natural compounds that may impact health and disease statuses and includes purified substances from natural sources, plant extracts, dietary supplements, vitamins, phytonutrients, and various products with combinations of functional ingredients. In this review, we summarize the current knowledge on the immunomodulatory effects of nutraceuticals with a special focus on the cancer microenvironment, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of nutraceuticals for envisioning future therapies employing nutraceuticals as chemoadjuvants.

Effects of titanium dioxide nanoparticles on the myocardium of the adult albino rats and the protective role of β-carotene (histological, immunohistochemical and ultrastructural study)

Titanium dioxide nanoparticles (TiO₂ NPs) are the most produced nanomaterials. TiO₂ NPs are used as a drug carrier and molecular imaging vehicle in the cardiovascular system. We aimed to study TiO₂ NPs effects on the ventricular myocardium and evaluate the ameliorative effects of β-carotene (βC). Forty adult albino rats were divided into four groups: negative control group (Ι) received a distilled water. Treated group (II): received 20 mg/kg/day TiO₂NPs intraperitoneally. Protected group (III): received 10 mg/kg/day βC orally together with TiO₂ NPs in a dose of 20 mg/kg/day intraperitoneally. Positive control group (IV) was given βC orally in a dose of 10 mg/kg/day for 14 days. Sections were stained with hematoxylin & eosin, bromphenol blue (BPB), and periodic acid Schiff (PAS). Anti-desmin & anti-CD45 immunohistochemical staining and electron microscopic examination were performed. Group (II) revealed fragmented myofibrils and inflammatory infiltrations. In group (III), normal cardiomyocytes with less inflammatory infiltrations. The optical density of PAS and BPB staining and anti-desmin showed a very highly significant decrease in the group (II) versus the control groups (P < 0.001). A highly significant increase in the optical density of group (III) versus group (II) (P < 0.01). Also, the area percentage mean values of collagen fibers and anti-CD45 in the group (II) showed a very highly significant increase versus the control groups (P < 0.001). Group (III) revealed a very highly significant decrease in the area percentage versus group (II) (P < 0.001). In conclusion: TiO₂ NPs adversely affected the histological structure of the adult rat ventricular myocardium in acute exposure (14 days) and the damage was less with βC.

β-Carotene and its physiological metabolites: Effects on oxidative status regulation and genotoxicity in in vitro models

Carotenoids are ubiquitously distributed in nature, β-carotene being the most frequently found carotenoid in the human diet. In the human body, β-carotene is absorbed, distributed and metabolized by enzymatic and/or non-enzymatic oxidant cleavage into several metabolites. Despite the broadly accepted biological value of β-carotene, it has also been considered a double-edged sword, mainly due to its potential antioxidant versus pro-oxidant behaviour. In this sense, the aim of this work was to scrutinize the antioxidant or pro-oxidant potential of β-carotene and its metabolites, namely trans-β-apo-8'-carotenal and β-ionone. Several parameters were evaluated in this study, viz. their effects on reactive species production, both in human whole blood and neutrophils; their effects on lipid peroxidation, in the absence and presence of peroxynitrite anion (ONOO^-) or hydrogen peroxide (H₂O₂), using a synaptosomal model; and finally, their putative genotoxic effects in the human hepatic HepG2 cell line. In general, depending on the cellular model and conditions tested, β-carotene and its metabolites revealed antioxidant effects to varying degrees without significant pro-oxidant or genotoxic effects.

Spinacia oleracea L. extract attenuates hippocampal expression of TNF-α and IL-1β in rats exposed to chronic restraint stress

Background: Restraint stress causes inflammation in nervous system that leads to emersion of neurodegenerative diseases. Spinach (Spinacia oleracea L.) contains different agents with antioxidant, antiapoptosis, and hepatoprotective properties. This study examined the effect of spinach hydroalcoholic extract (SHE) on TNF-α and IL-1β expression in hippocampus of male Wistar rats exposed to chronic restraint stress.

Methods: Rats were divided into 6 groups of 5: (1) control (intact); (2) nS-S200; (3) nS-S400; (4) stress; (5) stress-S200; (6) stressS400. Groups 2 and 3 and groups 5 and 6 received S. oleracea leaf hydroalcoholic extract in 200 and 400 mg/kg doses for 21 consecutive days by gavage. Groups 4, 5 and 6 were put in a restrainer 6 hours per day for 21 consecutive days. Then, the expression of IL-1β and TNF-α mRNAs and neuronal death in the hippocampus of rats were assessed by real time PCR and Nissl staining, respectively. Oneway analysis of variance was used for data analysis, and p<0.05 was considered statistically significant.

Results: The results showed that the expression of IL-1β and TNF-α was increased in hippocampus of rats exposed to stress compared to control groups (p<0.001). Furthermore, the expression of these proinflammatory cytokines was decreased in the stress-S200 and stress-S400 groups when compared to stress group (p<0.001). Immobility also caused neuronal death in CA1 region of hippocampus, and SHE reduced damage in CA1 pyramidal neurons layer in stressed rats.

Conclusion: Spinach decreases neuroinflammation in hippocampus of stressed rats, which may be due to its abundant antiinflammatory and antioxidant phytochemicals. The results of this study suggest that spinach may be effective in the prevention and treatment of neurodegenerative diseases.

Randomised Clinical Trial: Calorie Restriction Regimen with Tomato Juice Supplementation Ameliorates Oxidative Stress and Preserves a Proper Immune Surveillance Modulating Mitochondrial Bioenergetics of T-Lymphocytes in Obese Children Affected by Non-Alcoholic Fatty Liver Disease (NAFLD)

Fatty liver disease is a serious complication of childhood obesity. Calorie-restricted regimen (RCR) is one of the effective therapy for this condition. Aim of the study was to evaluate the effect of lycopene-rich tomato sauce with oregano and basil extracts in obese children with fatty liver on RCR. 61 obese children with fatty liver were enrolled, 52 completed the study. A randomized cross over clinical trial was performed. Participants were assigned to RCR alone or with a supplement of lycopene-rich tomato juice for 60 days; subsequently, the groups were switched to the alternative regimen for the next 60 days. Reduction in BMI, HOMA-IR, cholesterol, triglycerides, liver size, and steatosis was more profound in tomato-supplemented group. Leptin decreased in both groups whereas adiponectin raised only after tomato supplementation. RCR is associated with the impaired engagement of T-cells glycolysis and proliferation, tomato-supplementation resulted in glycolytic metabolic activation of T-cells. Tomato juice ameliorates glucose and lipid metabolism in obese children, improve oxidative and inflammatory state and modulates the mitochondrial metabolism of T-cells contributing to a maintenance of a proper immune surveillance in children, impaired by RCR. The addition of tomato to RCR could be considered a protective and preventive support to obese child.

Spinacia oleracea Linn Considered as One of the Most Perfect Foods: A Pharmacological and Phytochemical Review

Background: :

Leaves of Spinacia oleracea have been widely used as vegetarian foods. Some studies on the chemical composition of spinach have shown that it contains a high content of micronutrients (vitamins and minerals), and has an important economic value with some agronomic advantages. S. oleracea in traditional medicine is reported to cure more than one health problem.

Objective: :

This review focuses on the ethnopharmacological uses and pharmacological and phytochemical studies of Spinacia oleracea.

Method: :

Information on S. oleracea was obtained via electronic search of scientific databases such as Scopus, PubMed, Google Scholar, Scirus, Science Direct, Scielo, Web of Science, Medline, Springerlink, BioMed Central (BMC), and SciFinder for publications on this plant. In addition, books on medicinal herbs were also consulted.

Results: :

Approximately 100 chemical compounds were isolated and characterized from S. oleracea. The major active components of the plant are flavones, flavanols, methylenedioxyflavonol glucuronides, glucuronides, and carotenoids, which were extensively investigated. This review revealed potential pharmacological properties of these isolated compounds such as anti-obesity, anti-α-amylase, bileacid binding capacity, anti-mutagenic, anti-oxidant, anticancer, anti-inflammatory, cognitive and mood effect, hypoglycemic, and anti-hypertriglyceridemia.

Conclusions::

S. oleracea is an important edible plant also used for ethnomedical therapy of obesity, inflammation of lungs, lumbago, flatulence, and treatment of urinary calculi. Pharmacological and phytochemical studies of this plant including bioactives, which have been adequately studied, support its uses in traditional medicine. Additionally, prospects and future trends of this plant are proposed.

Inhibitory Effect of β-Carotene on Helicobacter pylori-Induced TRAF Expression and Hyper-Proliferation in Gastric Epithelial Cells

Helicobacter pylori infection causes the hyper-proliferation of gastric epithelial cells that leads to the development of gastric cancer. Overexpression of tumor necrosis factor receptor associated factor (TRAF) is shown in gastric cancer cells. The dietary antioxidant β-carotene has been shown to counter hyper-proliferation in H. pylori-infected gastric epithelial cells. The present study was carried out to examine the β-carotene mechanism of action. We first showed that H. pylori infection decreases cellular IκBα levels while increasing cell viability, NADPH oxidase activity, reactive oxygen species production, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation, and TRAF1 and TRAF2 gene expression, as well as protein–protein interaction in gastric epithelial AGS cells. We then demonstrated that pretreatment of cells with β-carotene significantly attenuates these effects. Our findings support the proposal that β-carotene has anti-cancer activity by reducing NADPH oxidase-mediated production of ROS, NF-κB activation and NF-κB-regulated TRAF1 and TRAF2 gene expression, and hyper-proliferation in AGS cells. We suggest that the consumption of β-carotene-enriched foods could decrease the incidence of H. pylori-associated gastric disorders.

The protective role of lutein on isoproterenol-induced cardiac failure rat model through improving cardiac morphology, antioxidant status via positively regulating Nrf2/HO-1 signalling pathway

Context: Lutein (LU) is a major carotenoid with various pharmacological activities including anti-inflammatory, antioxidant and anti-apoptosis. Objective: The cardioprotective efficacy of LU was determined by evaluating the biochemical and histopathological changes in isoproterenol (ISO) induced myocardial infarction (MI) rat model. Materials and methods: Healthy male albino rats (n = 40) were segregated into 4 equal groups. Group I (control) rats were administered with olive oil, Group II (LU) rats were orally pre-treated with only 40 mg of LU for 28 days, Group III (MI induced) rats were injected (subcutaneously; s.c) with 85 mg/kg of ISO for 2 consecutive days, whereas Group IV (LU + ISO) rats were pre-treated with 40 mg of LU for 28 days before ISO induction. Results: ISO-induced group showed increased infarct size and cardiac/inflammatory/apoptotic markers. However, pre-treatment with LU (28 days) considerably reduced (p < 0.01) the infarct size (14%), lipid peroxidation product (MDA;42%), cardiac markers [(lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), cardiac troponin T (cTn T)], inflammatory markers [IL-1β, IL-6, tumour necrosis factor alpha (TNF-α), nuclear factor kappa B p65 subunit (NF-κB p65)] and apoptotic markers (caspase-3 and -9). Also, LU significantly improved (p < 0.01) the antioxidants [catalase (CAT), superoxide dismutase (SOD)] as well as markedly upregulated (p < 0.01) the protein expression of HO-1 and Nrf2. Moreover, LU considerably reversed all the histopathological changes and thus exhibits its cardioprotective activity. Conclusion: LU exhibits potent cardioprotective activity against ISO-induced cardiotoxicity and might be recommended with standard cardioprotective agents for treating various MI-related complications.

β-carotene Inhibits Expression of c-Myc and Cyclin E in Helicobacter pylori-infected Gastric Epithelial Cells

Background

Helicobacter pylori infection is a major risk factor in the development of gastric cancer. H. pylori infection of gastric epithelial cells increases the levels of reactive oxygen species (ROS), activates oncogenes, and leads to β-catenin-mediated hyper-proliferation. β-Carotene reduces ROS levels, inhibits oxidant-mediated activation of inflammatory signaling and exhibits anticancer properties. The present study was carried out to determine if β-carotene inhibits H. pylori-induced cell proliferation and the expression of oncogenes c-myc and cyclin E by reducing the levels of β-catenin and phosphorylated glycogen synthase kinase 3β (p-GSK3β).

Methods

Gastric epithelial AGS cells were pre-treated with β-carotene (5 and 10 μM) for 2 hours prior to H. pylori infection and cultured for 6 hours (for determination of the levels of p-GSK3β, GSK3β, and β-catenin) and 24 hours (for determination of cell viability and protein levels of c-myc and cyclin E). Cell viability was determined by the MTT assay and protein levels were determined via western blot-based analysis.

Results

β-Carotene inhibited H. pylori-induced increases in the percentage of viable cells, phosphorylated GSK3β (p-GSK3β), and the levels of β-catenin, c-myc and cyclin E.

Conclusions

β-Carotene inhibits H. pylori-induced hyper-proliferation of gastric epithelial cells by suppressing β-catenin signaling and oncogene expression.

Lutein Complex Supplementation Increases Ocular Blood Flow Biomarkers in Healthy Subjects

Introduction: To investigate the effects of a lutein complex supplementation on ocular blood flow in healthy subjects. Materials and Methods: Sixteen healthy female patients (mean age 36.8 ± 12.1 years) were enrolled in this randomized, placebo-controlled, double-blinded, two-period crossover study. Subjects received daily an oral dose of the lutein with synergistic phytochemicals complex (lutein (10 mg), ascorbic acid (500 mg), tocopherols (364 mg), carnosic acid (2.5 mg), zeaxanthin (2 mg), copper (2 mg), with synergistic effects in reducing pro-inflammatory mediators and cytokines when administered together in combination) and placebo during administration periods. Measurements were taken before and after three-week supplementation periods, with crossover visits separated by a three-week washout period. Data analysis included blood pressure, heart rate, intraocular pressure, visual acuity, contrast sensitivity detection, ocular perfusion pressure, confocal scanning laser Doppler imaging of retinal capillary blood flow, and Doppler imaging of the retrobulbar blood vessels. Results: Lutein complex supplementation produced a statistically significant increase in mean superior retinal capillary blood flow, measured in arbitrary units (60, p = 0.0466) and a decrease in the percentage of avascular area in the superior (-0.029, p = 0.0491) and inferior (-0.023, p = 0.0477) retina, as well as reduced systolic (-4.06, p = 0.0295) and diastolic (-3.69, p = 0.0441) blood pressure measured in mmHg from baseline. Data comparison between the two supplement groups revealed a significant decrease in systemic diastolic blood pressure (change from pre- to post-treatment with lutein supplement (mean (SE)): -3.69 (1.68); change from pre- to post-treatment with placebo: 0.31 (2.57); p = 0.0357) and a significant increase in the peak systolic velocity (measured in cm/sec) in the central retinal artery (change from pre- to post-treatment with lutein supplement: 0.36 (0.19); change from pre- to post-treatment with placebo: -0.33 (0.21); p = 0.0384) with lutein complex supplement; data analyses from the placebo group were all non-significant. Discussion: In healthy participants, oral administration of a lutein phytochemicals complex for three weeks produced increased ocular blood flow biomarkers within retinal vascular beds and reduced diastolic blood pressure compared to placebo.

Lutein prevents osteoarthritis through Nrf2 activation and downregulation of inflammation

INTRODUCTION

Osteoarthritis is an inflammatory disorder associated with oxidative stress and apoptosis leading to cartilage destruction and impairment of cartilage formation. In the present study, we studied the protective effect of lutein against monosodium iodoacetate (MIA)-induced osteoarthritis in primary chondrocyte cells.

MATERIAL AND METHODS

Oxidative stress was determined through testing antioxidant status, reactive oxygen species levels and lipid peroxide content. Also, Nrf2 expression and its downstream target genes HO-1 and NQO-1 were determined. Inflammation was analyzed through NF-κB, COX-2 and pro-inflammatory cytokines (IL-6, TNF-α, IL-1β). In addition, the effects of MIA and lutein on mitochondrial membrane potential and caspase-3 levels were analyzed.

RESULTS

The results showed that lutein treatment significantly increased the cell viability of chondrocytes and offered significant cytoprotection by enhancing the antioxidant defense mechanisms and reducing oxidative stress (reactive oxygen species and lipid peroxidation). Lutein treatment showed anti-inflammatory effects by downregulating inflammatory proteins (NF-κB, COX-2) and pro-inflammatory cytokines (IL-6, TNF-α, IL-1β). Lutein reduced MIA-induced apoptosis through maintaining mitochondrial membrane potential and downregulating caspase-3 activity.

CONCLUSIONS

The present study shows significant cytoprotection offered by lutein against MIA-induced oxidative stress, inflammation and apoptosis by the modulatory effect of NF-κB and Nrf2 activation.

β-Carotene Inhibits Activation of NF-κB, Activator Protein-1, and STAT3 and Regulates Abnormal Expression of Some Adipokines in 3T3-L1 Adipocytes

Background

Oxidative stress occurs in white adipose tissue and dysregulates the expression of adipokines secreted from adipocytes. Since adipokines influence inflammation, supplementation with antioxidants might be beneficial for preventing oxidative stress-mediated inflammation in adipocytes and inflammation-associated complications. β-Carotene is the most prominent antioxidant carotenoid and scavenges reactive oxygen species in various tissues. The purpose of this study was to determine whether β-carotene regulates the expression of adipokines, such as adiponectin, monocyte chemoattractant protein-1 (MCP-1), and regulated on activation, normal T cell expressed and secreted (RANTES) in 3T3-L1 adipocytes treated with glucose/glucose oxidase (G/GO).

Methods

3T3-L1 adipocytes were cultured with or without β-carotene and treated with G/GO, which produces H₂O₂. mRNA and protein levels in the medium were determined by a real-time PCR and an ELISA. DNA binding activities of transcription factors were assessed using an electrophoretic mobility shift assay.

Results

G/GO treatment increased DNA binding affinities of redox-sensitive transcription factors, such as NF-κB, activator protein-1 (AP-1), and STAT3. G/GO treatment reduced the expression of adiponectin and increased the expression of MCP-1 and RANTES. G/GO-induced activations of NF-κB, AP-1, and STAT3 were inhibited by β-carotene. G/GO-induced dysregulation of adiponectin, MCP-1, and RANTES were significantly recovered by treatment with β-carotene.

Conclusions

β-Carotene inhibits oxidative stress-induced inflammation by suppressing pro-inflammatory adipokines MCP-1 and RANTES, and by enhancing adiponectin in adipocytes. β-Carotene may be beneficial for preventing oxidative stress-mediated inflammation, which is related to adipokine dysfunction.

4,4'-diaponeurosporene, a C30 carotenoid, effectively activates dendritic cells via CD36 and NF-κB signaling in a ROS independent manner

Carotenoids could be divided into C30 carotenoids and C40 carotenoids. The immune functions of C40 carotenoids had been extensively researched, while those of C30 carotenoids still remain unclear. In this study, the immune functions of a biosynthetic C30 carotenoid, 4,4'-diaponeurosporene (Dia), were identified on dendritic cells (DCs). DCs treated with 1 μM Dia for 24 h showed morphologic and phenotypic characteristics of mature state and had an increased production of IL-6, IL-10, IL-12p70 and TNFα, while β-carotene had a suppressive effect on DCs maturation. Moreover, Dia promoted antigen uptake of DCs in vitro and increased the quantity of antigen loaded DCs in mesenteric lymph nodes (MLN). Dia-treated DCs also had an enhanced ability to stimulate T cell proliferation and Th1 polarization. Further researches showed that Dia activated DCs via CD36 as well as ERK, JNK, and NF-κB signals in a reactive oxygen species (ROS) independent manner.

Bioaccessibility, Cellular Uptake, and Transport of Astaxanthin Isomers and their Antioxidative Effects in Human Intestinal Epithelial Caco-2 Cells

The bioaccessibility, bioavailability, and antioxidative activities of three astaxanthin geometric isomers were investigated using an in vitro digestion model and human intestinal Caco-2 cells. This study demonstrated that the trans-cis isomerization of all-E-astaxanthin and the cis-trans isomerization of Z-astaxanthins could happen both during in vitro gastrointestinal digestion and cellular uptake processes. 13Z-Astaxanthin showed higher bioaccessibility than 9Z- and all-E-astaxanthins during in vitro digestion, and 9Z-astaxanthin exhibited higher transport efficiency than all-E- and 13Z-astaxanthins. These might explain why 13Z- and 9Z-astaxanthins are found at higher concentrations in human plasma than all-E-astaxanthin in reported studies. All three astaxanthin isomers were effective in maintaining cellular redox homeostasis as seen in the antioxidant enzyme (CAT, SOD) activities ; 9Z- and 13Z- astaxanthins exhibited a higher protective effect than all-E-astaxanthin against oxidative stress as demonstrated by the lower cellular uptake of Z-astaxanthins and lower secretion and gene expression of the pro-inflammatory cytokine IL-8 in Caco-2 cells treated with H₂O₂. We conclude, for the first time, that Z-astaxanthin isomers may play a more important role in preventing oxidative stress induced intestinal diseases.

Identification and biological activities of carotenoids from the freshwater alga Oedogonium intermedium

The chemical and biological properties of carotenoids in the freshwater alga Oedogonium intermedium were investigated in this study. Carotenoids were extracted from the alga by dichloromethane and purified by saponification. The carotenoid content was determined both spectrometrically and by HPLC, the carotenoids identified by HPLC-PDA-APCI-IT-TOF-MS and the extracts analysed for several health-related bioactivities. The crude and saponified extracts contained 3,411.2±20.7 and 2,929.6±5.9µg carotenoids/g dry algal biomass, respectively. Seven major carotenoids were identified, namely neoxanthin, 9'-cis-neoxanthin, loroxanthin, violaxanthin, lutein, α-carotene and β-carotene, which were present in similar amounts in the alga. Both the crude and saponified carotenoid extracts exhibited significant antioxidant activities as well as potent inhibitory effects against several metabolically important enzymes including α-amylase, α-glucosidase, pancreatic lipase and hyaluronidase, but they were poor inhibitors of angiotensin converting enzyme (ACE). Oedogonium could be an important new source of carotenoids, specifically loroxanthin, which is lacking in terrestrial plants.

Alterations of plasma concentrations of lipophilic antioxidants are associated with Guillain-Barre syndrome

BACKGROUND

Guillain-Barré syndrome (GBS) is an acute inflammatory polyneuropathy resulting in demyelination in peripheral nervous system. Myelin enriched in lipids is easily oxidized by reactive oxygen species during inflammation. Oxidative stress and lipophilic anti-oxidative capacities in GBS patients have not been fully explored. To evaluate the redox status of GBS patients, we measured malondialdehyde (MDA), myeloperoxidase (MPO), lipophilic antioxidants, and tocopherols concentrations in plasma from GBS patients and age-matched healthy controls.

RESULTS

Concentrations of γ-tocopherol and δ-tocopherol decreased significantly, and α-carotene significantly increased in GBS patients compared to healthy controls. However, no significant changes in MDA and MPO concentrations were detected. In GBS patients, the γ-tocopherol concentration correlated positively with concentrations of δ-tocopherol, α-tocopherol, lutein, Q10, and γ-CEHC, respectively. Similarly, the δ-tocopherol concentration correlated positively with γ-tocopherol, α-tocopherol, lutein, Q10, δ-CEHC, and γ-CEHC concentrations, respectively. The receiver operating characteristics curve analysis showed that γ-tocopherol may serve as a good predictor for GBS.

CONCLUSIONS

Diminished lipophilic antioxidant defense, mainly γ-tocopherol and δ-tocopherol, in GBS patients accounting for their lowered resistance to reactive oxygen species is probably associated with pathogenesis of GBS, and potentially useful for the development of therapeutic strategies.

Lutein protects against β-amyloid peptide-induced oxidative stress in cerebrovascular endothelial cells through modulation of Nrf-2 and NF-κb

In the present study, we determined the protective role of lutein against Aβ _25-35 peptide-induced oxidative stress and apoptosis in bEND.3 cells. Cell viability was determined through MTT assay. Reactive oxygen species, lipid peroxides, and antioxidant enzyme activities were evaluated to analyze the oxidative stress status. NF-κB and Nrf-2 downstream target protein expressions were determined through western blot. Apoptosis was analyzed through caspase activities and subG1 accumulation. The results showed that Aβ _25-35 significantly increased (p < 0.001) oxidative stress biomarkers. Aβ _25-35 significantly up-regulated NF-κB nuclear expression and down-regulated Nrf-2 levels and HO-1 and, NQO-1 expressions. Aβ _25-35 induced apoptosis through decreasing mitochondrial membrane potential and increasing caspase 9 and 3 activities. Lutein pre-treatment significantly (p < 0.001) improved cell viability and decreased ROS levels (p < 0.001) and lipid peroxidation (p < 0.01). Lutein prevented Aβ _25-35-induced NF-κB nuclear expressions and up-regulated Nrf-2 expressions. Further, lutein also improved mitochondrial membrane potential and down-regulated caspase activities and subG1 accumulation. The present study shows the protective role of lutein against Aβ _25-35-induced toxicity by modulating Nrf-2 and NF-κB expressions in cerebrovascular endothelial cells.

The Multiple Facets of Lutein: A Call for Further Investigation in the Perinatal Period

Lutein may have important antioxidant actions in free-radical-mediated diseases, in addition to its well-known antioxidant and cytoprotective effects on macula and photoreceptors. The peculiar perinatal susceptibility to oxidative stress indicates that prophylactic use of antioxidants as lutein could help to prevent or at least to reduce oxidative stress related diseases in newborns. Since lutein is not synthesized by humans, the intake primarily depends on diet or supplementation. Newborns receive lutein exclusively from breast milk. Lutein supplementation in term newborns has been reported to reduce oxidative stress and increase antioxidant capacities in the first days of life. Innovative frontiers concerning lutein supplementation are orientated toward cardiometabolic health improvement and cognitive benefits. The safety of lutein as an antioxidant agent has been confirmed in experimental and clinical studies, but its routine use is not recommended in perinatal period. This review summarizes what is known about the role of lutein as an antioxidant and anti-inflammatory agent in animal model and humans.

Functional properties of spinach (Spinacia oleracea L.) phytochemicals and bioactives

Overwhelming evidence indicates that diets rich in fruits and vegetables are protective against common chronic diseases, such as cancer, obesity and cardiovascular disease. Leafy green vegetables, in particular, are recognized as having substantial health-promoting activities that are attributed to the functional properties of their nutrients and non-essential chemical compounds. Spinach (Spinacia oleracea L.) is widely regarded as a functional food due to its diverse nutritional composition, which includes vitamins and minerals, and to its phytochemicals and bioactives that promote health beyond basic nutrition. Spinach-derived phytochemicals and bioactives are able to (i) scavenge reactive oxygen species and prevent macromolecular oxidative damage, (ii) modulate expression and activity of genes involved in metabolism, proliferation, inflammation, and antioxidant defence, and (iii) curb food intake by inducing secretion of satiety hormones. These biological activities contribute to the anti-cancer, anti-obesity, hypoglycemic, and hypolipidemic properties of spinach. Despite these valuable attributes, spinach consumption remains low in comparison to other leafy green vegetables. This review examines the functional properties of spinach in cell culture, animals and humans with a focus on the molecular mechanisms by which spinach-derived non-essential phytochemicals and bioactives, such as glycolipids and thylakoids, impart their health benefits.

Glutamine Deprivation Causes Hydrogen Peroxide-induced Interleukin-8 Expression via Jak1/Stat3 Activation in Gastric Epithelial AGS Cells

BACKGROUND

The Janus kinase (Jak)/Signal transducers of activated transcription (Stat) pathway is an upstream signaling pathway for NF-κB activation in Helicobacter pylori-induced interleukin (IL)-8 production in gastric epithelial AGS cells. H. pylori activates NADPH oxidase and produces hydrogen peroxide, which activates Jak1/Stat3 in AGS cells. Therefore, hydrogen peroxide may be critical for IL-8 production via Jak/Stat activation in gastric epithelial cells. Glutamine is depleted during severe injury and stress and contributes to the formation of glutathione (GSH), which is involved in conversion of hydrogen peroxide into water as a cofactor for GSH peroxidase.

METHODS

We investigated whether glutamine deprivation induces hydrogen peroxide-mediated IL-8 production and whether hydrogen peroxide activates Jak1/Stat3 to induce IL-8 in AGS cells. Cells were cultured in the presence or absence of glutamine or hydrogen peroxide, with or without GSH or a the Jak/Stat specific inhibitor AG490.

RESULTS

Glutamine deprivation decreased GSH levels, but increased levels of hydrogen peroxide and IL-8, an effect that was inhibited by treatment with GSH. Hydrogen peroxide induced the activation of Jak1/Stat3 time-dependently. AG490 suppressed hydrogen peroxide- induced activation of Jak1/Stat3 and IL-8 expression in AGS cells, but did not affect levels of reactive oxygen species in AGS cells.

CONCLUSIONS

In gastric epithelial AGS cells, glutamine deprivation increases hydrogen peroxide levels and IL-8 expression, which may be mediated by Jak1/Stat3 activation. Glutamine supplementation may be beneficial for preventing gastric inflammation by suppressing hydrogen peroxide-mediated Jak1/Stat3 activation and therefore, reducing IL-8 production. Scavenging hydrogen peroxide or targeting Jak1/Stat3 may also prevent oxidant-mediated gastric inflammation.

Bioactive Compounds Isolated from Microalgae in Chronic Inflammation and Cancer

The risk of onset of cancer is influenced by poorly controlled chronic inflammatory processes. Inflammatory diseases related to cancer development include inflammatory bowel disease, which can lead to colon cancer, or actinic keratosis, associated with chronic exposure to ultraviolet light, which can progress to squamous cell carcinoma. Chronic inflammatory states expose these patients to a number of signals with tumorigenic effects, including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPK) activation, pro-inflammatory cytokines and prostaglandins release and ROS production. In addition, the participation of inflammasomes, autophagy and sirtuins has been demonstrated in pathological processes such as inflammation and cancer. Chemoprevention consists in the use of drugs, vitamins, or nutritional supplements to reduce the risk of developing or having a recurrence of cancer. Numerous in vitro and animal studies have established the potential colon and skin cancer chemopreventive properties of substances from marine environment, including microalgae species and their products (carotenoids, fatty acids, glycolipids, polysaccharides and proteins). This review summarizes the main mechanisms of actions of these compounds in the chemoprevention of these cancers. These actions include suppression of cell proliferation, induction of apoptosis, stimulation of antimetastatic and antiangiogenic responses and increased antioxidant and anti-inflammatory activity.

A Combination of Single-Nucleotide Polymorphisms Is Associated with Interindividual Variability in Dietary β-Carotene Bioavailability in Healthy Men

BACKGROUND

The bioavailability of β-carotene, the main dietary provitamin A carotenoid, varies among individuals. It is not known whether this variability can affect long-term β-carotene, and hence vitamin A, status.

OBJECTIVES

We hypothesized that variations in genes involved in β-carotene absorption and postprandial metabolism could at least partially explain the high interindividual variability in β-carotene bioavailability. Thus, the main objectives of this study were to identify associated single-nucleotide polymorphisms (SNPs), and to estimate whether populations with different allele frequencies at these SNPs could have different abilities to absorb provitamin A carotenoids.

METHODS

In this single-group design, 33 healthy, nonobese adult men were genotyped with the use of whole-genome microarrays. After an overnight fast, they consumed a test meal containing 100 g tomato puree providing 0.4 mg β-carotene. The postprandial plasma chylomicron β-carotene concentration was then measured at regular time intervals over 8 h. Partial least squares (PLS) regression was used to identify the best combination of SNPs in or near candidate genes (54 genes representing 2172 SNPs) that was associated with the postprandial chylomicron β-carotene response (incremental β-carotene area-under-the-curve concentration over 8 h in chylomicrons).

RESULTS

The postprandial chylomicron β-carotene response was highly variable (CV = 105%) and was positively correlated with the fasting plasma β-carotene concentration (r = 0.78; P < 0.0001). A significant (P = 6.54 × 10(-3)) multivalidated PLS regression model, which included 25 SNPs in 12 genes, explained 69% of the variance in the postprandial chylomicron β-carotene response, i.e., β-carotene bioavailability.

CONCLUSIONS

Interindividual variability in β-carotene bioavailability appears to be partially modulated by a combination of SNPs in 12 genes. This variability likely affects the long-term blood β-carotene status. A theoretic calculation of β-carotene bioavailability in 4 populations of the international HapMap project suggests that populations with different allele frequencies in these SNPs might exhibit a different ability to absorb dietary β-carotene. This trial was registered at clinicaltrials.gov as NCT02100774.

Lutein suppresses inflammatory responses through Nrf2 activation and NF-κB inactivation in lipopolysaccharide-stimulated BV-2 microglia

SCOPE

In this study, the effects of lutein on neuroinflammation in lipopolysaccharide (LPS)-activated BV-2 microglia were investigated.

METHODS AND RESULTS

The production of proinflammatory cytokines tumor necrosis factor-α, interleukin-1β, and nitric oxide was measured in culture medium using enzyme immunoassay and Griess reagent, respectively. The expression of proteins was determined using Western blot. Pretreatment with lutein (50 μM) prior to LPS (1 μg/mL, 12 h) stimulation resulted in a significant inhibition of inducible nitric oxide synthase and cyclooxygenase-2 expression, as well as tumor necrosis factor-α, interleukin-1β, and nitric oxide production (p < 0.05). Further experiments demonstrated that lutein suppressed LPS-induced NF-κB activation by inhibiting the phosphorylation of p38 kinase, c-Jun N-terminal kinase (JNK), and Akt kinase (p < 0.05). Moreover, lutein markedly quenched reactive oxygen species and promoted antioxidant protein expression including heme oxygenase-1 and

NAD(P)H

quinone oxidoreductase by enhancing the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) mediated NF-E2-related factor 2 (Nrf2) activation (p < 0.05).

CONCLUSION

These results suggest that lutein attenuates neuroinflammation in LPS-activated BV-2 microglia partly through inhibiting p38-, JNK-, and Akt-stimulated NF-κB activation and promoting ERK-induced Nrf2 activation, suggesting that lutein has great potential as a nutritional preventive strategy in inflammation-related neurodegenerative disorders.

Carotenoid consumption is related to lower lipid oxidation and DNA damage in middle-aged men

The present cross-sectional study assessed the potential relationships of carotenoid intake with lipid and oxidative stress markers in middle-aged men. A total of 296 apparently healthy middle-aged men (mean age 50.5 (SD 5.0) years, BMI 25.8 (SD 3.5) kg/m(2)) were recruited to participate in the study. Dietary intake, anthropometry, blood pressure, lifestyle features, blood and urine biomarkers were assessed using validated procedures. The lipid markers included NEFA, Castelli index, and TAG:HDL ratio; oxidative stress markers included urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-iso-PGF2α and plasma oxidised-LDL (ox-LDL). We observed a significant inverse association (P < 0.05) between NEFA concentrations and consumption of lutein plus zeaxanthin, β-carotene, α-carotene and total carotenoid, while Castelli index was negatively associated with daily intake of lycopene, β-carotene and total carotenoids. Regarding oxidative stress biomarkers, urinary 8-OHdG and ox-LDL concentrations were also inversely associated (P < 0.05) with consumption of lycopene, lutein plus zeaxanthin, β-carotene, α-carotene and total carotenoids, regardless of confounding variables. Moreover, there was a negative association of urinary 8-iso-PGF2α concentration with dietary lutein plus zeaxanthin (β - 0.135, 95% CI - 0.268, - 0.001), β-carotene (β - 0.156, 95% CI - 0.277, - 0.034) and with the sum of all carotenoids (β - 0.189, 95% CI - 0.333, - 0.046). In conclusion, total daily carotenoid intake based on five investigated carotenoid types (β-cryptoxanthin, lycopene, lutein plus zeaxanthin, β-carotene and α-carotene) was inversely associated with relevant lipid and oxidative stress markers in middle-aged men, with emphasis on β-carotene that was negatively associated with five of the six lipid and oxidative stress markers evaluated in the present study.

Mechanistic insight into beta-carotene-mediated protection against ulcerative colitis-associated local and systemic damage in mice

PURPOSE

Ulcerative colitis (UC), a chronic gastrointestinal disorder, is a debilitating disease affecting many people across the globe. Research suggests that the levels of several antioxidants, including β-carotene (β-CAR), decrease in the serum of patients with UC. The present study was aimed at elucidating the molecular mechanisms involved in β-CAR-mediated protection against UC in mice.

METHODS

UC was induced in mice using 3%w/v dextran sulfate sodium in drinking water for two cycles; one cycle comprised of 7 days of dextran sulfate sodium-treated water followed by 14 days of normal drinking water. β-CAR was administered at the doses of 5, 10 and 20 mg/kg bw/day, po throughout the experiment. The effect of β-CAR in mice with UC was evaluated using biochemical parameters, histological evaluation, comet and micronucleus assays, immunohistochemistry and Western blot analysis.

RESULTS

The results indicated that β-CAR treatment ameliorated the severity of UC by modulating various molecular targets such as nuclear factor-kappa B, cyclooxygenase-2, interleukin 17, signal transducer and activator of transcription 3, nuclear erythroid 2-related factor 2, matrix metalloproteinase-9 and connective tissue growth factor. Further, β-CAR treatment maintained the gut integrity by increasing the expression of a tight junction protein, occludin, which was decreased in the colon of mice with UC. Also β-CAR treatment significantly reduced UC-associated elevated plasma lipopolysaccharide level, systemic inflammation and genotoxicity.

CONCLUSION

β-CAR ameliorated UC-associated local and systemic damage in mice by acting on multiple targets.

Carotenoids, inflammation, and oxidative stress--implications of cellular signaling pathways and relation to chronic disease prevention

Several epidemiologic studies have shown that diets rich in fruits and vegetables reduce the risk of developing several chronic diseases, such as type 2 diabetes, atherosclerosis, and cancer. These diseases are linked with systemic, low-grade chronic inflammation. Although controversy persists on the bioactive ingredients, several secondary plant metabolites have been associated with these beneficial health effects. Carotenoids represent the most abundant lipid-soluble phytochemicals, and in vitro and in vivo studies have suggested that they have antioxidant, antiapoptotic, and anti-inflammatory properties. Recently, many of these properties have been linked to the effect of carotenoids on intracellular signaling cascades, thereby influencing gene expression and protein translation. By blocking the translocation of nuclear factor κB to the nucleus, carotenoids are able to interact with the nuclear factor κB pathway and thus inhibit the downstream production of inflammatory cytokines, such as interleukin-8 or prostaglandin E2. Carotenoids can also block oxidative stress by interacting with the nuclear factor erythroid 2-related factor 2 pathway, enhancing its translocation into the nucleus, and activating phase II enzymes and antioxidants, such as glutathione-S-transferases. In this review, which is organized into in vitro, animal, and human investigations, we summarized current knowledge on carotenoids and metabolites with respect to their ability to modulate inflammatory and oxidative stress pathways and discuss potential dose-health relations. Although many pathways involved in the bioactivity of carotenoids have been revealed, future research should be directed toward dose-response relations of carotenoids, their metabolites, and their effect on transcription factors and metabolism.

Lipid and protein oxidation in newborn infants after lutein administration

Objectives. To test the hypothesis that neonatal supplementation with lutein in the first hours of life reduces neonatal oxidative stress (OS) in the immediate postpartum period. Methods. A randomized controlled, double-blinded clinical trial was conducted among 150 newborns divided into control group, not supplemented (n = 47), and test group, supplemented with lutein on the first day postpartum (n = 103). Blood Samples were collected at birth from cord and at 48 hrs postpartum while routine neonatal metabolic screenings were taking place. Total hydroperoxide (TH), advanced oxidation protein products (AOPP), and biological antioxidant potential (BAP) were measured by spectrophotometry and data were analyzed by Wilcoxon rank sum test and by multivariate logistic regression analysis. Results. Before lutein supplementation, the mean blood concentrations of AOPP, TH, and BAP were 36.10 umol/L, 156.75 mmol/H₂O₂, and 2361.04 umol/L in the test group. After lutein supplementation, significantly higher BAP increment (0.17 ± 0.22 versus 0.06 versus ± 0.46) and lower TH increment (0.46 ± 0.54 versus 0.34 ± 0.52) were observed in the test group compared to controls. Conclusion. Neonatal supplementation with lutein in the first hours of life increases BAP and reduces TH in supplemented babies compared to those untreated. The generation of free radical-induced damage at birth is reduced by lutein. This trial is registered with ClinicalTrials.gov NCT02068807.

Procaterol but not dexamethasone protects 16HBE cells from H₂O₂-induced oxidative stress

Oxidative stress is an important pathophysiological factor of asthma and chronic obstructive pulmonary disease (COPD). We hypothesized that procaterol and dexamethasone might treat inflammation through inhibiting oxidative stress in vitro. This study evaluated procaterol and dexamethasone in the hydrogen peroxide (H2O2)-induced immortal human bronchial epithelial cell model of oxidative stress and investigated the underlying mechanisms. Results showed that exposure to 125 μM H2O2 for 2 h led to a 50% reduction in the cell viability, significantly increased the percentage of apoptosis, and elevated levels of malondialdehyde and reactive oxygen species. Pretreatment with procaterol (25 - 200 nM) could reduce these effects in a dose-dependent manner. In contrast, pretreatment with dexamethasone (100 nM, 1000 nM) was inefficient. Pretreatment with procaterol plus dexamethasone (100 nM procaterol + 1000 nM dexamethasone) was effective, but the combined effect was not more effective than the sole pretreatment with 100 nM procaterol. The nuclear factor kappa-B (NF-κB) pathway was involved in the pathogenic mechanisms of H2O2. Procaterol may indirectly inhibit H2O2-induced activation of the NF-κB pathway due to its capability of antioxidation. Glucocorticoids may be not recommended to treat asthma or COPD complicated with severe oxidative stress.

Anti-inflammatory activity of bioaccessible fraction from Eryngium foetidum leaves

Eryngium foetidum (EF) has long been used as a medicinal plant and culinary spice in tropical regions. Phytochemicals in its leaves have been proposed to be responsible for the anti-inflammatory and antioxidant activities. The present study used in vitro digestion coupled with Caco-2 cells to assess such activities. Caco-2 cells were incubated with aqueous fraction from simulated digestion (bioaccessible fraction) of EF leaves with/without bile extract prior to stimulation with interleukin-1 beta (IL-1β). Monocyte chemoattractant protein-1 (MCP-1) and IL-8 in culture media and the intracellular reactive oxygen species (ROS) were measured. Approximately 24% β-carotene and 35% lutein of leaves were present in the aqueous fraction. The transfer of caffeic and chlorogenic acids to the aqueous fraction was 76%-81%, while that of kaempferol was 48%. Prior incubation of Caco-2 cells with the bioaccessible fraction suppressed IL-1β activated IL-8 and MCP-1 by 33%, but the fraction lacking mixed micelles decreased IL-8 and MCP-1 levels only by 11%. The pretreatment of Caco-2 cells with the bioaccessible fraction of EF reduced ROS by 34%; the fraction lacking mixed micelles decreased ROS by 28%. These data suggest that bioactive compounds partitioning in mixed micelles play a significant role to suppress the proinflammatory insult but with a modest antioxidant effect.

Lutein protects against methotrexate-induced and reactive oxygen species-mediated apoptotic cell injury of IEC-6 cells

Purpose

High-dose chemotherapy using methotrexate (MTX) frequently induces side effects such as mucositis that leads to intestinal damage and diarrhea. Several natural compounds have been demonstrated of their effectiveness in protecting intestinal epithelial cells from these adverse effects. In this paper, we investigated the protection mechanism of lutein against MTX-induced damage in IEC-6 cells originating from the rat jejunum crypt.

Methods

The cell viability, induced-apoptosis, reactive oxygen species (ROS) generation, and mitochondrial membrane potential in IEC-6 cells under MTX treatment were examined in the presence or absence of lutein. Expression level of Bcl2, Bad and ROS scavenging enzymes (including SOD, catalase and Prdx1) were detected by quantitative RT-PCR.

Results

The cell viability of IEC-6 cells exposed to MTX was decreased in a dose- and time-dependent manner. MTX induces mitochondrial membrane potential loss, ROS generation and caspase 3 activation in IEC-6 cells. The cytotoxicity of MTX was reduced in IEC-6 cells by the 24 h pre-treatment of lutein. We found that pre-treatment of lutein significantly reduces MTX-induced ROS and apoptosis. The expression of SOD was up-regulated by the pre-treatment of lutein in the MTX-treated IEC-6 cells. These results indicated that lutein can protect IEC-6 cells from the chemo-drugs induced damage through increasing ROS scavenging ability.

Conclusion

The MTX-induced apoptosis of IEC-6 cells was shown to be repressed by the pre-treatment of lutein, which may represent a promising adjunct to conventional chemotherapy for preventing intestinal damages.