Carotenoid radical chemistry and antioxidant/pro-oxidant properties

Decrease of ESKAPE virulence with a cationic heme-mimetic gallium porphyrin photosensitizer: The Trojan horse strategy that could help address antimicrobial resistance

INTRODUCTION

Emerging antibiotic resistance among bacterial pathogens has forced an urgent need for alternative non-antibiotic strategies development that could combat drug resistant-associated infections. Suppression of virulence of ESKAPE pathogens' by targeting multiple virulence traits provides a promising approach.

OBJECTIVES

Here we propose an iron-blocking antibacterial therapy based on a cationic heme-mimetic gallium porphyrin (GaCHP), which antibacterial efficacy could be further enhanced by photodynamic inactivation.

METHODS

We used gallium heme mimetic porphyrin (GaCHP) excited with light to significantly reduce microbial viability and suppress both the expression and biological activity of several virulence traits of both Gram-positive and Gram-negative ESKAPE representatives, i.e., S. aureus and P. aeruginosa. Moreover, further improvement of the proposed strategy by combining it with routinely used antimicrobials to resensitize the microbes to antibiotics and provide enhanced bactericidal efficacy was investigated.

RESULTS

The proposed strategy led to substantial inactivation of critical priority pathogens and has been evidenced to suppress the expression and biological activity of multiple virulence factors in S. aureus and P. aeruginosa. Finally, the combination of GaCHP phototreatment and antibiotics resulted in promising strategy to overcome antibiotic resistance of the studied microbes and to enhance disinfection of drug resistant pathogens.

CONCLUSION

Lastly, considering high safety aspects of the proposed treatment toward host cells, i.e., lack of mutagenicity, no dark toxicity and mild phototoxicity, we describe an efficient alternative that simultaneously suppresses the functionality of multiple virulence factors in ESKAPE pathogens.

Cyanobacterial myxoxanthophylls: biotechnological interventions and biological implications

Cyanobacteria safeguard their photosynthetic machinery from oxidative damage caused by adverse environmental factors such as high-intensity light. Together with many photoprotective compounds, they contain myxoxanthophylls, a rare group of glycosidic carotenoids containing a high number of conjugated double bonds. These carotenoids have been shown to: have strong photoprotective effects, contribute to the integrity of the thylakoid membrane, and upregulate in cyanobacteria under a variety of stress conditions. However, their metabolic potential has not been fully utilized in the stress biology of cyanobacteria and the pharmaceutical industry due to a lack of mechanistic understanding and their insufficient biosynthesis. This review summarizes current knowledge on: biological function, genetic regulation, biotechnological production, and pharmaceutical potential of myxoxanthophyll, with a focus on strain engineering and parameter optimization strategies for increasing their cellular content. The summarized knowledge can be utilized in cyanobacterial metabolic engineering to improve the stress tolerance of useful strains and enhance the commercial-scale synthesis of myxoxanthophyll for pharmaceutical uses.

Association of dietary carotenoid intake with the prevalence kidney stones among the general adult population

PURPOSE

This study was to examine whether higher dietary carotenoid intake levels were associated with a lower prevalence of kidney stones.

MATERIALS AND METHODS

This study analyzed data from 2007 to 2018 National Health and Nutrition Examination Survey (NHANES) project. Dietary carotenoid intake (α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein/zeaxanthin) was assessed using two 24-h dietary recall interviews. Multiple logistic regression and weighted quantile sum (WQS) regression were applied to examine the associations between five dietary carotenoids alone, compounds, and the prevalence of kidney stones. The dose-response relationships were analyzed by restricted cubic spline regression.

RESULTS

A total of 30,444 adults (2909 participants with kidney stones) were included in the analysis. The mean age of the participants was 49.95 years and 49.2% of the participants were male. Compared with the first quartile, the fourth quartile of α-carotene (odds ratio [OR] = 0.82 [0.73-0.92]), β-carotene (OR = 0.79 [0.70-0.89]), β-cryptoxanthin (OR = 0.88 [0.79-0.99]), and lutein/zeaxanthin (OR = 0.80 [0.71-0.91]) were significantly and inversely associated with the prevalence of kidney stones after adjusting for confounders. The dose-response analysis showed a linear relationship between five dietary carotenoid intake levels and the prevalence of kidney stones. Further WQS analysis revealed that the combination of all five dietary carotenoids was negatively associated with and the prevalence of kidney stones, with the largest effect coming from β-carotene (weight = 0.538).

CONCLUSION

Our findings indicated that higher dietary carotenoid intake levels were associated with decreased prevalence of kidney stones, and increasing the intake of foods rich in β-carotene may prevent the development of kidney stones.

Dietary carotenoids intake and sex differences in relation to chronic kidney disease a cross-sectional assessment in the NHANES study

BACKGROUND AND AIMS

Current evidence on the relationship between dietary carotenoids intake (DCI) and chronic kidney disease (CKD) are limited. Moreover, whether there is an association between DCI and prevalence of CKD and how this association might be impacted by sex is not clear.

METHODS AND RESULTS

Overall, 4507 women and 4396 men were included for analysis. The study used data from the National Health and Nutrition Examination Survey (NHANES), a cross-sectional survey carried out in the USA. The exposure factor for this analysis was DCI. The outcome was CKD, defined as eGFR < 60mL/min/1.73 m2. Multivariate logistic regression was used to analyzed the associations of DCI and prevalence of CKD both in men and women. There was a significant inverse association between higher DCI and prevalence of CKD only among females. Per LgDCI unit increment, the multivariable adjusted odd ratio (OR) (95% confidence interval) for prevalence of CKD was 0.72 (0.58, 0.90) in females and 0.95 (0.77, 1.18) in males. When compared with the lowest quartile, the ORs of the highest quartile of DCI for prevalence of CKD were 0.59 (0.40, 0.87) in females and 0.87 (0.60, 1.26) in males. The associations remained similar in the subgroup analyses.

CONCLUSIONS

The findings suggest that a higher intake of dietary carotenoids is associated with a lower prevalence of CKD in women, but not in men.

Scavenging of Cation Radicals of the Visual Cycle Retinoids by Lutein, Zeaxanthin, Taurine, and Melanin

In the retina, retinoids involved in vision are under constant threat of oxidation, and their oxidation products exhibit deleterious properties. Using pulse radiolysis, this study determined that the bimolecular rate constants of scavenging cation radicals of retinoids by taurine are smaller than 2 × 107 M-1s-1 whereas lutein scavenges cation radicals of all three retinoids with the bimolecular rate constants approach the diffusion-controlled limits, while zeaxanthin is only 1.4-1.6-fold less effective. Despite that lutein exhibits greater scavenging rate constants of retinoid cation radicals than other antioxidants, the greater concentrations of ascorbate in the retina suggest that ascorbate may be the main protectant of all visual cycle retinoids from oxidative degradation, while α-tocopherol may play a substantial role in the protection of retinaldehyde but is relatively inefficient in the protection of retinol or retinyl palmitate. While the protection of retinoids by lutein and zeaxanthin appears inefficient in the retinal periphery, it can be quite substantial in the macula. Although the determined rate constants of scavenging the cation radicals of retinol and retinaldehyde by dopa-melanin are relatively small, the high concentration of melanin in the RPE melanosomes suggests they can be scavenged if they are in proximity to melanin-containing pigment granules.

Exploring the Antioxidant and Genoprotective Potential of Salicornia ramosissima Incorporation in the Diet of the European Seabass (Dicentrarchus labrax)

The identification of novel feed materials as a source of functional ingredients is a topical priority in the finfish aquaculture sector. Due to the agrotechnical practices associated and phytochemical profiling, halophytes emerge as a new source of feedstuff for aquafeeds, with the potential to boost productivity and environmental sustainability. Therefore, the present study aimed to assess the potential of Salicornia ramosissima incorporation (2.5, 5, and 10%), for 2 months, in the diet of juvenile European seabass, seeking antioxidant (in the liver, gills, and blood) and genoprotective (DNA and chromosomal integrity in blood) benefits. Halophyte inclusion showed no impairments on growth performance. Moreover, a tissue-specific antioxidant improvement was apparent, namely through the GSH-related defense subsystem, but revealing multiple and complex mechanisms. A genotoxic trigger (regarded as a pro-genoprotective mechanism) was identified in the first month of supplementation. A clear protection of DNA integrity was detected in the second month, for all the supplementation levels (and the most prominent melioration at 10%). Overall, these results pointed out a functionality of S. ramosissima-supplemented diets and a promising way to improve aquaculture practices, also unraveling a complementary novel, low-value raw material, and a path to its valorization.

Astaxanthin Protects against Alcoholic Liver Injury via Regulating Mitochondrial Redox Balance and Calcium Homeostasis

Increasing evidence points to the critical role of calcium overload triggered by mitochondrial dysfunction in the development of alcoholic liver disease (ALD). As an important organelle for aerobic respiration with a double-layered membrane, mitochondria are pivotal targets of alcohol metabolism-mediated lipid peroxidation, wherein mitochondria-specific phospholipid cardiolipin oxidation to 4-hydroxynonenal (4-HNE) ultimately leads to mitochondrial integrity and function impairment. Therefore, it is absolutely essential to identify effective nutritional intervention targeting mitochondrial redox function for an alternative therapy of ALD, in order to compensate for the difficulty in achieving alcohol withdrawal due to addiction. In this study, we confirmed the significant advantages of astaxanthin (AX) against alcohol toxicity among various carotenoids via cell experiments and identified the potential in mitochondrion morphogenesis and calcium signaling pathway by bioinformatics analysis. The ALD model of Sprague-Dawley (SD) rats was also generated to investigate the effectiveness of AX on alcohol-induced liver injury, and the underlying mechanisms were further explored. AX intervention attenuated alcohol-induced oxidative stress and lipid peroxidation as well as mitochondrial dysfunction characterized by degenerative morphology changes and collapsed membrane potential. Also, AX reduced the production of 4-HNE by activating the Nrf2-ARE signaling pathway, which is closely associated with the redox balance of mitochondria. In addition, relieved mitochondrial Ca2+ accumulation caused by AX was observed both in vivo and in vitro. Furthermore, we revealed the structure-activity relationship of AX and mitochondrial membrane channel proteins MCU and VDAC1, implying potential acting targets. Altogether, our data indicated a new mechanism of AX intervention which protects against alcohol-induced liver injury through restoring redox balance and Ca2+ homeostasis in mitochondria, as well as provided novel insights into the development of AX as a therapeutic option for the management of ALD.

Optimized fed-batch cultivation of Rhodotorula toruloides in a bubble column bioreactor progressed the β-carotene production from corn steep liquor

In this work, a new isolate yeast, namely Rhodotorula toruloides KP324973, was examined for β-carotene production from corn steep liquor (CSL) as a sole carbon source because CSL as the by-product of corn wet-milling process mainly enriched from the water-soluble carbohydrates. The studies were preliminary performed at the shaken flasks, and then developed at batch and fed-batch modes in a bubble column reactor (BCR). Application of the BCR improved the carotenogenesis of the cells in comparison with shaken flasks and the specific β-carotene production rate (Rp) and the yield of β-carotene production from the total reducing sugars (YP/TRS) reached 2.23 mg gcell-1 h-1 and 36.82 mg gTRS-1, respectively. Further studies were carried out to optimize the operational factors of the BCR for a fed-batch production by the response surface methodology. An optimal condition at a feed flow rate of 2.5 mL h-1, temperature 11.7°C, and initial pH of 6.1 obtained the highest Rp = 12.31 mg gcell-1 h-1 and YP/TRS = 97.18 mg gTRS-1.

Advancing nutrition science to meet evolving global health needs

Populations in crisis!A global overview of health challenges and policy efforts within the scope of current nutrition issues, from persistent forms of undernutrition, including micronutrient deficiency, to diet-related chronic diseases. Nutrition science has evolved from a therapeutic and prevention emphasis to include a focus on diets and food systems. Working and consensus definitions are needed, as well as guidance related to healthy diets and the emerging issues that require further research and consensus building. Between nutrient deficiency and chronic disease, nutrition has evolved from focusing exclusively on the extremes of overt nutrient deficiency and chronic disease prevention, to equipping bodies with the ability to cope with physiologic, metabolic, and psychological stress. Just what is 'optimal nutrition', is that a valid public health goal, and what terminology is being provided by the nutrition science community? Nutrition research on 'healthspan', resilience, and intrinsic capacity may provide evidence to support optimal nutrition. Finally, experts provide views on ongoing challenges of achieving consensus or acceptance of the various definitions and interventions for health promotion, and how these can inform government health policies.Nutrition topics that receive particular focus in these proceedings include choline, NAD-replenishment in neurodegenerative diseases, and xanthophyll carotenoids. Choline is a crucial nutrient essential for cellular metabolism, requiring consumption from foods or supplements due to inadequate endogenous synthesis. Maternal choline intake is vital for fetal and infant development to prevent neural tube defects. Neurodegenerative diseases pose a growing health challenge, lacking effective therapies. Nutrition, including NAD-replenishing nutrients, might aid prevention. Emerging research indicates xanthophyll carotenoids enhance vision and cognition, potentially impacting age-related diseases.

The Antioxidant and Anti-Inflammatory Effects of the Main Carotenoids from Tomatoes via Nrf2 and NF-κB Signaling Pathways

Oxidative stress and inflammation are crucial factors in the development of cardiovascular diseases. In previous research, the oxidative stress and inflammation models have frequently been explored independently. In the current study, we investigated the antioxidant and anti-inflammatory effects of tomato extract and its two main carotenoids (lutein and lycopene) with various concentrations using a rat cardiomyocyte model of co-existing oxidative stress and persistent chronic inflammation. It was discovered that the antioxidant effects of 0.5-5 μM lutein, 0.5-5 μM lycopene, and 50-200 μg/mL tomato extract increased in a dose-dependent manner. However, the pro-oxidation effects emerged by measuring the antioxidant-related indices, including the levels of ROS, SOD, and GPX in H9c2 cells as concentrations exceeded those mentioned above. The anti-inflammatory effects of lutein, lycopene, and tomato extract were simultaneously strengthened with higher concentrations, potentially due to the suppression of the NF-κB signaling pathway. Furthermore, high concentrations of lutein, lycopene, and tomato extract potentially regulated Nrf2/HO-1 and NF-κB signaling pathways dependent on TGF-1β and IL-10 to demonstrate high concentrations of pro-oxidation and anti-inflammation effects. Our findings indicate that the dose-effect regulatory mechanisms of antioxidant and anti-inflammatory properties among lutein, lycopene, and tomato extract will be advantageous in developing more effective therapeutic strategies to prevent cardiovascular diseases.

Robiginitalea aurantiaca sp. nov. and Algoriphagus sediminis sp. nov., isolated from coastal sediment

Two novel rod-shaped, Gram-stain-negative, aerobic and non-motile bacterial strains, designated M39T and C2-7T, were isolated from the coastal sediment of Xiaoshi Island, Weihai, PR China. Growth of strain M39T occurred at 15-37 °C, at pH 6.0-9.0 and in the presence of 1.0-9.0 % (w/v) NaCl. Strain C2-7T grew at 15-40 °C, at pH 6.0-8.0 and in the presence of 0.5-8.0 % (w/v) NaCl. Phylogenetic analysis based 16S rRNA gene sequences revealed that strains M39T and C2-7T belong to the phylum Bacteroidota. Based on the results of 16S rRNA gene sequence analysis, the closest relative of strain M39T was Robiginitalea marina KCTC 92035T (95.4 %), and the closest relative of strain C2-7T was Algoriphagus namhaensis DPG-3T (97.0 %). The percentage of conserved protein and average nucleotide identity values between strain M39T and some species of the genus Robiginitalea were 66.9-77.6% and 69.3-71.0 %, respectively, while those between strain C2-7T and some species of the genus Algoriphagus were 68.0-70.1% and 56.1-72.6 %, respectively. The major cellular fatty acids (>10 %) of strain M39T consisted of iso-C15 : 1 F, iso-C15 : 0 and iso-C17 : 0 3-OH, while those of strain C2-7T were iso-C15 : 0 and C16 : 1 ω7c/C16 : 1 ω6c. MK-6 was the only respiratory quinone that was compatible with the genus of strain M39T. The predominant menaquinone of strain C2-7T was MK-7. The major polar lipids of strain M39T were phosphatidylethanolamine and glycolipids, and those of strain C2-7T were phosphatidylethanolamine, one unidentified aminolipid and four unidentified lipids. The DNA G+C contents of strains M39T and C2-7T were 46.9 and 40.8 mol%, respectively. Based upon the results presented in this study, strains M39T and C2-7T represent novel species of the genera Robiginitalea and Algoriphagus, respectively, for which the names Robiginitalea aurantiaca sp. nov. and Algoriphagus sediminis sp. nov. are proposed with the type strains M39T (=MCCC 1H00498T=KCTC 92014T) and C2-7T (=MCCC 1H00414T=KCTC 92027T).

Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging

A physiological level of oxygen/nitrogen free radicals and non-radical reactive species (collectively known as ROS/RNS) is termed oxidative eustress or "good stress" and is characterized by low to mild levels of oxidants involved in the regulation of various biochemical transformations such as carboxylation, hydroxylation, peroxidation, or modulation of signal transduction pathways such as Nuclear factor-κB (NF-κB), Mitogen-activated protein kinase (MAPK) cascade, phosphoinositide-3-kinase, nuclear factor erythroid 2-related factor 2 (Nrf2) and other processes. Increased levels of ROS/RNS, generated from both endogenous (mitochondria, NADPH oxidases) and/or exogenous sources (radiation, certain drugs, foods, cigarette smoking, pollution) result in a harmful condition termed oxidative stress ("bad stress"). Although it is widely accepted, that many chronic diseases are multifactorial in origin, they share oxidative stress as a common denominator. Here we review the importance of oxidative stress and the mechanisms through which oxidative stress contributes to the pathological states of an organism. Attention is focused on the chemistry of ROS and RNS (e.g. superoxide radical, hydrogen peroxide, hydroxyl radicals, peroxyl radicals, nitric oxide, peroxynitrite), and their role in oxidative damage of DNA, proteins, and membrane lipids. Quantitative and qualitative assessment of oxidative stress biomarkers is also discussed. Oxidative stress contributes to the pathology of cancer, cardiovascular diseases, diabetes, neurological disorders (Alzheimer's and Parkinson's diseases, Down syndrome), psychiatric diseases (depression, schizophrenia, bipolar disorder), renal disease, lung disease (chronic pulmonary obstruction, lung cancer), and aging. The concerted action of antioxidants to ameliorate the harmful effect of oxidative stress is achieved by antioxidant enzymes (Superoxide dismutases-SODs, catalase, glutathione peroxidase-GPx), and small molecular weight antioxidants (vitamins C and E, flavonoids, carotenoids, melatonin, ergothioneine, and others). Perhaps one of the most effective low molecular weight antioxidants is vitamin E, the first line of defense against the peroxidation of lipids. A promising approach appears to be the use of certain antioxidants (e.g. flavonoids), showing weak prooxidant properties that may boost cellular antioxidant systems and thus act as preventive anticancer agents. Redox metal-based enzyme mimetic compounds as potential pharmaceutical interventions and sirtuins as promising therapeutic targets for age-related diseases and anti-aging strategies are discussed.

Identification of staphyloxanthin and derivates in yellow-pigmented Staphylococcus capitis subsp. capitis

Introduction

Staphylococcus capitis naturally colonizes the human skin but as an opportunistic pathogen, it can also cause biofilm-associated infections and bloodstream infections in newborns. Previously, we found that two strains from the subspecies S. capitis subsp. capitis produce yellow carotenoids despite the initial species description, reporting this subspecies as non-pigmented. In Staphylococcus aureus, the golden pigment staphyloxanthin is an important virulence factor, protecting cells against reactive oxygen species and modulating membrane fluidity.

Methods

In this study, we used two pigmented (DSM 111179 and DSM 113836) and two non-pigmented S. capitis subsp. capitis strains (DSM 20326T and DSM 31028) to identify the pigment, determine conditions under which pigment-production occurs and investigate whether pigmented strains show increased resistance to ROS and temperature stress.

Results

We found that the non-pigmented strains remained colorless regardless of the type of medium, whereas intensity of pigmentation in the two pigmented strains increased under low nutrient conditions and with longer incubation times. We were able to detect and identify staphyloxanthin and its derivates in the two pigmented strains but found that methanol cell extracts from all four strains showed ROS scavenging activity regardless of staphyloxanthin production. Increased survival to cold temperatures (-20°C) was detected in the two pigmented strains only after long-term storage compared to the non-pigmented strains.

Conclusion

The identification of staphyloxanthin in S. capitis is of clinical relevance and could be used, in the same way as in S. aureus, as a possible target for anti-virulence drug design.

Protective Effects of ζ-Carotene-like Compounds against Acute UVB-Induced Skin Damage

The previous study successfully established an expression strain of ζ-carotene-like compounds (CLC) and demonstrated its remarkable antioxidant activity, which exhibited resistance to photodamage caused by UVB radiation on the skin following gavage administration. The objective of this study was to investigate the impact and mechanism of CLC on UVB-induced skin damage through topical application. Cell viability, anti-apoptotic activity, ROS scavenging ability, the inhibition of melanin synthesis, the regulation of inflammatory factors and collagen deposition were assessed in cells and mice using qRT-PCR, WB, Elisa assays, immunohistochemistry staining and biochemical kits, etc. The experimental results demonstrated that CLC-mitigated apoptosis induced by UVB irradiation up-regulated the Keap1/Nrf2/ARE antioxidant pathway to attenuate levels of ROS and inflammatory factors (NF-κB, TNF-α, IL-6 and IL-β), and suppressed MAPK/AP-1 and CAMP/PKA/CREB signaling pathways to mitigate collagen degradation, skin aging and melanin formation. In conclusion, this study underscored the potential of CLC as a safe and efficacious source of antioxidants, positioning it as a promising ingredient in the formulation of cosmetics targeting anti-aging, skin brightening and sunburn repair.

Association between dietary carotenoids intake and chronic constipation in American men and women adults: a cross-sectional study

BACKGROUND

Dietary carotenoids have been proven to improve intestinal disorders like inflammatory bowel disease and colon cancer, yet little is known about the link between dietary carotenoids and constipation. This study aims to examine the relationship between dietary carotenoids intake and constipation, using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2010.

METHODS

A total of 11,722 participants were enrolled. Chronic constipation was defined as type 1 (separate hard lumps, like nuts) and type 2 (sausage-like, but lumpy) in the Bristol stool form scale (BSFS). Carotenoids intake was obtained from the average of two 24-hour dietary recall questionnaires (if only one 24-hour was available, we used it) and divided into quartiles (Q). The prevalence of constipation was calculated across men and women individuals. The relationship between dietary carotenoids intake and constipation in men and women was assessed with weighted logistic regression and smoothed curve fitting after adjusting confounders, with results displayed as weighted odds ratio (OR) with 95% confidence intervals (95% CI). The model was further stratified by age, race, and HEI 2015 scores (with median as cutoff) among men and women.

RESULTS

The total weighted prevalence of chronic constipation in this study was 8.08%, 11.11% in women and 5.18% in men. After multivariable adjustment, compared with the lowest intake, participants with the highest dietary lycopene intake (ORQ4 vs. Q1= 0.55, 95% CI: 0.36-0.84, p for trend = 0.01) and total lycopene intake (ORQ4 vs. Q1 = 0.52, 95% CI: 0.34-0.80, p for trend = 0.01) were negatively associated with the risk of chronic constipation in men, whereas increased dietary α-carotene intake reduced the risk of chronic constipation in women (ORQ4 vs. Q1 = 0.69, 95% CI: 0.48-0.98, p for trend = 0.04). Smoothing curve fitting further supported these results and provided evidence of dose-response effects. No association was found between other types of carotenoids and chronic constipation in men and women.

CONCLUSIONS

Increasing lycopene intake may improve bowel function in men while increased α-carotene intake may reduce the risk of chronic constipation in women. Further studies are essential to explore the role that the intake of carotenoids plays in chronic constipation.

Prevention of aspirin-mediated secondary toxicity by combined treatment of carotenoids in macrophages

Upon understanding the boosting role of carotenoids on the endogenous anti-inflammatory system, it is vital to explore their role in reducing the use of high doses of non-steroidal anti-inflammatory drug (NSAIDs), and their mediated secondary toxicity during the treatment of chronic diseases. The current study investigates the carotenoids potential on inhibition of secondary complications induced by NSAIDs, aspirin (ASA) against lipopolysaccharide (LPS) stimulated inflammation. Initially, this study evaluated a minimal cytotoxic dose of ASA and carotenoids (β-carotene, BC/lutein, LUT/astaxanthin, AST/fucoxanthin FUCO) in Raw 264.7, U937, and peripheral blood mononuclear cells (PBMCs). In all three cells, carotenoids + ASA treatment reduced the LDH release, NO, and PGE2 efficiently than an equivalent dose of carotenoid or ASA treated alone. Based on cytotoxicity and sensitivity results, RAW 264.7 cells were selected for further cell-based assay. Among carotenoids, FUCO + ASA exhibited an efficient reduction of LDH release, NO, and PGE2 than the other carotenoids (BC + ASA, LUT + ASA, and AST + ASA) treatment. FUCO + ASA combination decreased LPS/ASA induced oxidative stress, pro-inflammatory mediators (iNOS, COX-2, and NF-κB), and cytokines (IL-6, TNF-α, and IL-1β) efficiently. Further, apoptosis was inhibited by 69.2% in FUCO + ASA, and 46.7% in ASA than LPS treated cells. A drastic decrease in intracellular ROS generation with the increase in GSH was observed in FUCO + ASA compared to LPS/ASA groups. The results documented on the low dose of ASA with a relative physiological concentration of FUCO suggested greater importance for alleviating secondary complications and optimize prolonged chronic disease treatments with NSAID's associated side effects.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03632-w.

The Endless World of Carotenoids-Structural, Chemical and Biological Aspects of Some Rare Carotenoids

Carotenoids are a large and diverse group of compounds that have been shown to have a wide range of potential health benefits. While some carotenoids have been extensively studied, many others have not received as much attention. Studying the physicochemical properties of carotenoids using electron paramagnetic resonance (EPR) and density functional theory (DFT) helped us understand their chemical structure and how they interact with other molecules in different environments. Ultimately, this can provide insights into their potential biological activity and how they might be used to promote health. In particular, some rare carotenoids, such as sioxanthin, siphonaxanthin and crocin, that are described here contain more functional groups than the conventional carotenoids, or have similar groups but with some situated outside of the rings, such as sapronaxanthin, myxol, deinoxanthin and sarcinaxanthin. By careful design or self-assembly, these rare carotenoids can form multiple H-bonds and coordination bonds in host molecules. The stability, oxidation potentials and antioxidant activity of the carotenoids can be improved in host molecules, and the photo-oxidation efficiency of the carotenoids can also be controlled. The photostability of the carotenoids can be increased if the carotenoids are embedded in a nonpolar environment when no bonds are formed. In addition, the application of nanosized supramolecular systems for carotenoid delivery can improve the stability and biological activity of rare carotenoids.

The Bioactive Properties of Carotenoids from Lipophilic Sea buckthorn Extract (Hippophae rhamnoides L.) in Breast Cancer Cell Lines

In women, breast cancer is the most commonly diagnosed cancer (11.7% of total cases) and the leading cause of cancer death (6.9%) worldwide. Bioactive dietary components such as Sea buckthorn berries are known for their high carotenoid content, which has been shown to possess anti-cancer properties. Considering the limited number of studies investigating the bioactive properties of carotenoids in breast cancer, the aim of this study was to investigate the antiproliferative, antioxidant, and proapoptotic properties of saponified lipophilic Sea buckthorn berries extract (LSBE) in two breast cancer cell lines with different phenotypes: T47D (ER+, PR+, HER2-) and BT-549 (ER-, PR-, HER2-). The antiproliferative effects of LSBE were evaluated by an Alamar Blue assay, the extracellular antioxidant capacity was evaluated through DPPH, ABTS, and FRAP assays, the intracellular antioxidant capacity was evaluated through a DCFDA assay, and the apoptosis rate was assessed by flow cytometry. LSBE inhibited the proliferation of breast cancer cells in a concentration-dependent manner, with a mean IC₅₀ of 16 µM. LSBE has proven to be a good antioxidant both at the intracellular level, due to its ability to significantly decrease the ROS levels in both cell lines (p = 0.0279 for T47D, and p = 0.0188 for BT-549), and at the extracellular level, where the ABTS and DPPH inhibition vried between 3.38-56.8%, respectively 5.68-68.65%, and 35.6 mg/L equivalent ascorbic acid/g LSBE were recorded. Based on the results from the antioxidant assays, LSBE was found to have good antioxidant activity due to its rich carotenoid content. The flow cytometry results revealed that LSBE treatment induced significant alterations in late-stage apoptotic cells represented by 80.29% of T47D cells (p = 0.0119), and 40.6% of BT-549 cells (p = 0.0137). Considering the antiproliferative, antioxidant, and proapoptotic properties of the carotenoids from LSBE on breast cancer cells, further studies should investigate whether these bioactive dietary compounds could be used as nutraceuticals in breast cancer therapy.

The Synergy between Glutathione and Phenols-Phenolic Antioxidants Repair Glutathione: Closing the Virtuous Circle-A Theoretical Insight

Glutathione (GSH) and phenols are well-known antioxidants, and previous research has suggested that their combination can enhance antioxidant activity. In this study, we used Quantum Chemistry and computational kinetics to investigate how this synergy occurs and elucidate the underlying reaction mechanisms. Our results showed that phenolic antioxidants could repair GSH through sequential proton loss electron transfer (SPLET) in aqueous media, with rate constants ranging from 3.21 × 10⁶ M^-1 s^-1 for catechol to 6.65 × 10⁸ M^-1 s^-1 for piceatannol, and through proton-coupled electron transfer (PCET) in lipid media with rate constants ranging from 8.64 × 10⁶ M^-1 s^-1 for catechol to 5.53 × 10⁷ M^-1 s^-1 for piceatannol. Previously it was found that superoxide radical anion (O₂^•-) can repair phenols, thereby completing the synergistic circle. These findings shed light on the mechanism underlying the beneficial effects of combining GSH and phenols as antioxidants.

Antioxidant and Anti-Inflammatory Effects of Carotenoids in Mood Disorders: An Overview

Depression has a multifactorial etiology comprising family history and unemployment. This review aims to summarize the evidence available for the antioxidant and anti-inflammatory effects of carotenoids in mood disorders. This review article’s methodologies were based on a search of the PubMed database for all linked published papers. Epidemiological studies indicate that a diet rich in vegetables, fruits, nuts, fish, and olive oil may prevent the development of depression. Antioxidant supplementation has been found to combat various stress-induced psychiatric disorders, including depression and anxiety. A growing body of evidence indicates that carotenoids have both antioxidant and anti-inflammatory. Studies also suggest that poor dietary intake, particularly low intakes of fruit and vegetables and high intakes of fast food and other convenience foods, may increase the risk of developing depression. Thus, dietary interventions have the potential to help mitigate the risk of mental health decline in both the general population and those with mood disorders. Considering that carotenoids have both antioxidant and anti-inflammatory effects, it is expected that they might exert a promising antidepressant effect. Nevertheless, further studies (including interventional and mechanistic studies) assessing the effect of carotenoids on preventing and alleviating depression symptoms are needed.

Spectroscopic biofeedback on cutaneous carotenoids: A powerful tool for primary prevention in advanced age

Antioxidants exhibit a powerful defense mechanism against aging and chronic disease. The human skin reflects the overall antioxidant status of the body. The cutaneous carotenoid concentration is a biomarker for individual nutritional intake of antioxidants, as it correlates with the overall antioxidant status. The cutaneous carotenoid concentrations of 44 adults were measured using a multiple spatially resolved reflection spectroscopy. During the first phase of the study, measurements of carotenoid concentrations were performed without revealing the antioxidant status, followed by an intervention phase during which the volunteers were informed about their individual values by biofeedback. During the third phase, biofeedback was combined with an additional intake of fruit juices. Across time points, participants showed increasing levels of carotenoid status. Thus, biofeedback leads to an improvement of the carotenoid value of the skin. Providing a biofeedback measurement to monitor the individual antioxidative status may be an easy and cost-effective way of primary prevention.

Lycopene prevents Di-(2-ethylhexyl) phthalate-induced mitophagy and oxidative stress in mice heart via modulating mitochondrial homeostasis

Di-(2-ethylhexyl) phthalate (DEHP) is a plasticizer that is easily found in the environment. Excessive daily exposure of it may lead to an increased risk of cardiovascular disease (CVD). Lycopene (LYC), as a natural carotenoid, has been shown to have the potential to prevent CVD. However, the mechanism of LYC on cardiotoxicity caused by DEHP exposure is unknown. The research was aimed to investigate the chemoprotection of LYC on the cardiotoxicity caused by DEHP exposure. Mice were treated with DEHP (500 mg/kg or 1,000 mg/kg) and/or LYC (5 mg/kg) for 28 d by intragastric administration, and the heart was subjected to histopathology and biochemistry analysis. The results indicated that DEHP caused cardiac histological alterations and enhanced the activity of cardiac injury indicators, and interfered with mitochondrial function and activating mitophagy. Notably, LYC supplementation could inhibit DEHP-induced oxidative stress. The mitochondrial dysfunction and emotional disorder caused by DEHP exposure were significantly improved through the protective effect of LYC. We concluded that LYC enhances mitochondrial function by regulating mitochondrial biogenesis and dynamics to antagonize DEHP-induced cardiac mitophagy and oxidative stress.

Structural Features of Small Molecule Antioxidants and Strategic Modifications to Improve Potential Bioactivity

This review surveys the major structural features in various groups of small molecules that are considered to be antioxidants, including natural and synthetic compounds alike. Recent advances in the strategic modification of known small molecule antioxidants are also described. The highlight is placed on changing major physicochemical parameters, including log p, bond dissociation energy, ionization potential, and others which result in improved antioxidant activity.

The Role of Oxidative Status in the Pathogenesis of Primary Open-Angle Glaucoma, Pseudoexfolyation Syndrome and Glaucoma

PURPOSE

To investigate the role of oxidative stress and antioxidant system in the etiopathogenesis of pseudoexfoliation and progression of pseudoexfoliation syndrome to glaucoma.

MATERIAL AND METHOD

A total of 20 patients with pseudoexfoliation syndrome, 20 with pseudoexfoliation glaucoma, 20 with primary open-angle glaucoma, and 20 without pseudoexfoliation and glaucoma as a control group, who underwent cataract or glaucoma surgery between December 2020 and March 2021 in the Health Sciences University Beyoğlu Eye Training and Research Hospital, 80 patients were included in the study. Best corrected visual acuity (BCVA), intraocular pressure with applanation tonometry, detailed anterior and posterior segment examinations with biomicroscopy were performed in all patients included in the study. Approximately 0.1 cc of anterior chamber fluid was taken from all patients at the beginning of surgery. Total Oxidant Status (TOS) and Total Antioxidant Status (TAS) levels were measured by keeping the samples taken in the deep freezer of the cornea bank at -80 degrees, transferring them with cold chain transport rules, and examining them with automatic measurement method in the laboratories of the Medical Biochemistry Department of the University of Health Sciences. Oxidative Stress Index (OSI) value was calculated to measure the degree of oxidative stress.

RESULTS

TAS averages of the control and POAG groups were found to be statistically significantly higher than the PES and PEG groups (p = 0.0001, p = 0.0001). No significant difference was observed between the other groups (p > 0.05). The TOS averages of the control and POAG groups were found to be statistically significantly lower than the PES and PEG groups (p = 0.003, p = 0.0001; p = 0.01, p = 0.001), no statistically significant difference was observed between the other groups (p > 0.05). The OSI mean of the control and POAG groups was found to be statistically significantly lower than the PES and PEG groups (p = 0.001, p = 0.0001; p = 0.002, p = 0.0001), no statistically significant difference was observed between the other groups (p > 0.05).

CONCLUSION

Increased TOS and OSI and decreased TAS levels in the aqueous humour of patients with PES and PEG suggest that increased oxidative stress and decreased antioxidative defense system play a role in the etiopathogenesis of the disease.

Carotenoid biosynthesis is associated with low-temperature adaptation in Rhodosporidium kratochvilovae

BACKGROUND

Low temperatures greatly limit the growth of microorganisms. Low-temperature adaptation in microorganisms involves multiple mechanisms. Carotenoids are naturally occurring lipid-soluble pigments that act as antioxidants and protect cells and tissues from the harmful effects of free radicals and singlet oxygen. However, studies on the regulation of carotenoid biosynthesis at low temperatures in microorganisms are limited. In this study, we investigated the correlation between carotenoids and low-temperature adaptation in the cold-adapted strain of Rhodosporidium kratochvilovae YM25235.

RESULTS

Carotenoid biosynthesis in YM25235 was inhibited by knocking out the bifunctional lycopene cyclase/phytoene synthase gene (RKCrtYB) using the established CRISPR/Cas9 gene-editing system based on endogenous U6 promoters. The carotenoids were extracted with acetone, and the content and composition of the carotenoids were analyzed by spectrophotometry and HPLC. Then, the levels of reactive oxygen species (ROS) and the growth rate in YM25235 were determined at a low temperature. The results indicated that the carotenoid biosynthesis and ROS levels were increased in the YM25235 strain at a low temperature and inhibition of carotenoid biosynthesis was associated with higher ROS levels and a significant decrease in the growth rate of YM25235 at a low temperature.

CONCLUSIONS

The regulation of carotenoid biosynthesis was associated with low-temperature adaptation in YM25235. Our findings provided a strong foundation for conducting further studies on the mechanism by which YM25235 can adapt to low-temperature stress.

Antioxidant Defense and Pseudoexfoliation Syndrome: An Updated Review

Oxidative stress (OS) affects the anterior ocular tissues, rendering them susceptible to several eye diseases. On the other hand, protection of the eye from harmful factors is achieved by unique defense mechanisms, including enzymatic and non-enzymatic antioxidants. The imbalance between oxidants and antioxidants could be the cause of pseudoexfoliation syndrome (PEXS), a condition of defective extracellular matrix (ECM) remodeling. A systematic English-language literature review was conducted from May 2022 to June 2022. The main antioxidant enzymes protecting the eye from reactive oxygen species (ROS) are superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), which catalyze the reduction of specific types of ROS. Similarly, non-enzymatic antioxidants such as vitamins A, E and C, carotenoids and glutathione (GSH) are involved in removing ROS from the cells. PEXS is a genetic disease, however, environmental and dietary factors also influence its development. Additionally, many OS products disrupting the ECM remodeling process and modifying the antioxidative defense status could lead to PEXS. This review discusses the antioxidative defense of the eye in association with PEXS, and the intricate link between OS and PEXS. Understanding the pathways of PEXS evolution, and developing new methods to reduce OS, are crucial to control and treat this disease. However, further studies are required to elucidate the molecular pathogenesis of PEXS.

Association of Different ABO and Rh Blood Groups with the Erythroprotective Effect of Extracts from Navicula incerta and Their Anti-Inflammatory and Antiproliferative Properties

Previous studies have reported that different blood groups are associated with the risk of chronic degenerative diseases that mainly involve inflammation and neoplastic processes. We investigate the relationship between blood groups and the erythroprotective effect of extracts from Navicula incerta against oxidative damage as a proposal to develop drugs designed for people with a specific blood type related to chronic pathology. The study was carried out through the elucidation of the erythroprotective potential, anti-inflammatory and antiproliferative activity of Navicula incerta. Research suggests that the presence or absence of certain blood groups increases or decreases the abilities of certain phytochemicals to inhibit oxidative stress, which is related to the systemic inflammatory response involved in the development of different types of cancer. The pigment-rich extracts from Navicula incerta inhibit ROO•- induced oxidative stress in human erythrocytes on the A RhD+ve antigen without compromising the structure of the cell membrane. This result is very important, since the A antigen is related to the susceptibility of contracting prostate cancer. Similarly, it was possible to inhibit the proliferation of cervical (HeLa) and prostate (PC-3) carcinoma. The combinatorial analysis of different biological activities can help design phytochemicals as new candidates for preventive drugs treating the chronic degenerative diseases associated with a specific blood group.

The Influence of Circadian Rhythm on the Activity of Oxidative Stress Enzymes

The circadian system synchronizes daily with the day-night cycle of our environment. Disruption of this rhythm impacts the emergence and development of many diseases caused, for example, by the overproduction of free radicals, leading to oxidative damage of cellular components. The goal of this study was to determine the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione transferase (GST), glutathione reductase (R-GSSG), and the concentration of glutathione (GSH) in the circadian rhythm. The study group comprised 66 healthy volunteers (20-50 years; 33 women; 33 men). The blood was collected at 2, 8 a.m., and 2, 8 p.m. All samples marked the serum melatonin concentration to confirm the correct sleeping rhythm and wakefulness throughout the day. The activity of study enzymes and the concentration of GSH were measured by the spectrophotometric method. Confirmed the existence of circadian regulation of oxidative stress enzymes except for GST activity. The peak of activity of study enzymes and GSH concentration was observed at 2 a.m. The increased activity of enzymes and the increase in GSH concentration observed at night indicate that during sleep, processes allowing to maintain of the redox balance are intensified, thus limiting the formation of oxidative stress.

Vitamin A Nutritional Status Is a Key Determinant of Bone Mass in Children

The bone mass increases that occur during the period of childhood are of great significance for maximizing the peak bone mass in adults and preventing for osteoporosis. Studies have reported that VA can improve the bone health in adults. Moreover, limited studies have assessed such associations in children. In this cross-sectional study including 426 children, we assessed the children’s plasma retinol concentration by liquid chromatography–mass spectrometry and the dietary intake of VA and carotenoids using a structured Food Frequency Questionnaire. Their bone mineral content and bone mineral density (BMD) were measured using dual-energy X-ray absorptiometry. After adjusting for potential confounders, the restricted cubic spline revealed an inverted U-shaped association between plasma retinol concentration and BMD; the estimated effects on the TBLH BMD per μmol/L increase in the plasma retinol concentration were 1.79 × 10⁻² g/cm² below 1.24 μmol/L and −5.78 × 10⁻³ g/cm² above this point (p for non-linearity = 0.046). A multiple linear regression analysis revealed a positive association between the plasma retinol concentration and the TBLH BMC (β = 1.89, 95% CI: 1.64 × 10⁻¹–3.62, p = 0.032). In conclusion, an appropriate plasma retinol concentration and greater intakes of dietary VA and β-carotene may enhance the bone mineral status of children who are aged 6–9 years.

Phenotypic and genomic assessment of the potential threat of human spaceflight-relevant Staphylococcus capitis isolates under stress conditions

Previous studies have reported that spaceflight specific conditions such as microgravity lead to changes in bacterial physiology and resistance behavior including increased expression of virulence factors, enhanced biofilm formation and decreased susceptibility to antibiotics. To assess if spaceflight induced physiological changes can manifest in human-associated bacteria, we compared three spaceflight relevant Staphylococcus capitis isolates (DSM 111179, ISS; DSM 31028, clean room; DSM 113836; artificial gravity bedrest study) with the type strain (DSM 20326T). We tested the three strains regarding growth, colony morphology, metabolism, fatty acid and polar lipid pattern, biofilm formation, susceptibility to antibiotics and survival in different stress conditions such as treatment with hydrogen peroxide, exposure to desiccation, and irradiation with X-rays and UV-C. Moreover, we sequenced, assembled, and analyzed the genomes of all four strains. Potential genetic determinants for phenotypic differences were investigated by comparative genomics. We found that all four strains show similar metabolic patterns and the same susceptibility to antibiotics. All four strains were considered resistant to fosfomycin. Physiological differences were mainly observed compared to the type strain and minor differences among the other three strains. The ISS isolate and the bedrest study isolate exhibit a strong delayed yellow pigmentation, which is absent in the other two strains. Pigments were extracted and analyzed by UV/Vis spectroscopy showing characteristic carotenoid spectra. The ISS isolate showed the highest growth rate as well as weighted average melting temperature (WAMT) of fatty acids (41.8°C) of all strains. The clean room isolate showed strongest biofilm formation and a high tolerance to desiccation. In general, all strains survived desiccation better in absence of oxygen. There were no differences among the strains regarding radiation tolerance. Phenotypic and genomic differences among the strains observed in this study are not inevitably indicating an increased virulence of the spaceflight isolate. However, the increased growth rate, higher WAMT and colony pigmentation of the spaceflight isolate are relevant phenotypes that require further research within the human spaceflight context. We conclude that combining genetic analysis with classical microbiological methods allows the detailed assessment of the potential threat of bacteria in highly regulated and extreme environments such as spaceflight environments.

Geraniol inhibits biofilm formation of methicillin-resistant Staphylococcus aureus and increase the therapeutic effect of vancomycin in vivo

Methicillin-resistant Staphylococcus aureus (MRSA) is among the common drug resistant bacteria, which has gained worldwide attention due to its high drug resistance and infection rates. Biofilms produced by S. aureus are known to increase antibiotic resistance, making the treatment of S. aureus infections even more challenging. Hence, inhibition of biofilm formation has become an alternative strategy for controlling persistent infections. In this study, we evaluated the efficacy of geraniol as a treatment for MRSA biofilm infection. The results of crystal violet staining indicated that 256 μg/mL concentration of geraniol inhibited USA300 biofilm formation by 86.13% and removed mature biofilms by 49.87%. Geraniol exerted its anti-biofilm effect by influencing the major components of the MRSA biofilm structure. We found that geraniol inhibited the synthesis of major virulence factors, including staphyloxanthin and autolysins. The colony count revealed that geraniol inhibited staphyloxanthin and sensitized USA300 cells to hydrogen peroxide. Interestingly, geraniol not only reduced the release of extracellular nucleic acids (eDNA) but also inhibited cell autolysis. Real-time polymerase chain reaction data revealed the downregulation of genes involved in biofilm formation, which verified the results of the phenotypic analysis. Geraniol increased the effect of vancomycin in eliminating USA300 biofilms in a mouse infection model. Our findings revealed that geraniol effectively inhibits biofilm formation in vitro. Furthermore, in combination with vancomycin, geraniol can reduce the biofilm adhesion to the implant in mice. This suggests the potential of geraniol as an anti-MRSA biofilm drug and can provide a solution for the clinical treatment of biofilm infection.

Analysis of macular carotenoids in the developing macaque retina: The timeline of macular pigment development

In the mature retina, the components of the macular pigment, lutein (L), R,R-zeaxanthin (RRZ), R,S-zeaxanthin (RSZ, meso-zeaxanthin) are most concentrated in the central macula. L and RRZ are of dietary origin but RSZ is produced in situ from L. The relative proportions of L and Z isomers vary across the retina with eccentricity in the adult retina. Early reports have shown that during development, the proportions of L and Z isomers undergo changes as the total pigment levels increase. The methods described here demonstrate the unique utility of chiral phase HPLC to measure the amounts of L, RRZ, and RSZ, discriminating between the two zeaxanthin stereoisomers. In three concentric retinal sections of macaque retinas chiral phase HPLC has been employed to document the developmental changes in the distribution of each L, RSZ, and RRZ during the period just prior to full term gestation through 19 months after birth. The net rate of accumulation of carotenoids within the central retina during the first 20 months is quasi-linear and fit by a linear regression. During development, the rate of transport of L (0.12 (±0.033)ngmm^-2mo^-1 (SE)) into the central 2mm of the retina is double that of RRZ (0.062 (±0.02)ngmm^-2mo^-1 (SE)). The rate of accumulation of RSZ (0.06 (±0.01)ngmm^-2mo^-1 (SE)) is comparable to that of RRZ. In the peripheral retina, the rates of accumulation of L and RRZ are not correlated with increasing age, whereas accumulation of RSZ does correlate with age. The changing proportions of L to Z isomers in the central retina during development are explained by the rates for carotenoid accumulation within the central retina. At birth, the macular pigment in the central retina is dominated by L and RRZ, 0.35±0.11 and 0.21±0.054ngmm^-2. In the central retina, RSZ was rarely detected in the youngest tissues analyzed. It can be estimated to represent 6% of the total macular pigment (0.033±0.11ngmm^-2) at birth based on extrapolation from measurements in the peripheral retina and the ratio of L/(RRZ+RSZ) is ≈1.5. At maturity, the concentrations for L, RRZ, and RSZ in the central macaque retina are estimated to be 1.7, 1.8 and 1.08ngmm^-2, with L/(RRZ+RSZ) being 0.6.

Role of Toll-like Receptor/MyD88 Signaling in Lycopene Alleviated Di-2-ethylhexyl Phthalate (DEHP)-Induced Inflammatory Response

Lycopene (Lyc) has anti-inflammatory and antioxidant biological functions. Di-2-ethylhexyl phthalate (DEHP) is an extremely harmful and persistent environmental pollutant and is a threat to animal health. The toll-like receptor (TLR)/MyD88 pathway is an important pathway in the inflammatory response. To illustrate the potential antagonistic action of Lyc against DEHP by the TLR/MyD88 pathway, 140 ICR mice were randomly assigned groups and continuously gavaged with corn oil, distilled water, different DEHP concentrations (500 or 1000 mg/kg BW/day), and/or Lyc (5 mg/kg BW/day) for 28 days. The data show that Lyc effectively attenuates the DEHP-induced activation of the TLR/MyD88 pathway, the upregulation of JNK expression, the content of IL-6 and TNF-α, and the downregulation of the IL-10 content, which eventually inhibit the inflammatory response and mitochondrial injuries. These findings underline the TLR/MyD88 pathway as a potential therapeutic target in DEHP and Lyc as a new therapeutic method to inhibit DEHP toxicity.

The Benefits of High-Resistant Starch and Beta-Carotene Snack in Ameliorating Atherogenic Index and Inflammation in Obesity

BACKGROUND: In obesity, lipid abnormalities may be related to the higher risk of cardiovascular diseases associated with increased oxidation of lipids and inflammation. Resistant starch and beta-carotene reduce atherosclerosis risk related to low-grade inflammation and oxidative stress in obesity. AIM: This study aimed to evaluate the benefits of a snack containing high-resistant starch and beta-carotene in improving the atherogenic index of plasma (AIP) and inflammation in obesity. METHODS: This study used a single-blinded and randomized controlled design. Fifty subjects received 42 g of snacks per day for 6 weeks, either tested snacks or standard snacks. Anthropometry, body composition, lipid profile, tumor necrosis factor-alpha (TNF-α), and oxidized low-density lipoprotein (ox-LDL) were measured before and after intervention. RESULTS: The snack containing high-resistant starch and beta-carotene significantly decreased LDL, AIP, and TNF-α (p < 0.05). Positive correlations were found between AIP and triglycerides in both snacks (p < 0.05), LDL or TNF-α in the standard snack (p < 0.05), and TNF-α and ox-LDL in both snacks (p < 0.05). A negative correlation was found between AIP and HDL in both snacks (p < 0.05). CONCLUSIONS: A snack containing high-resistant starch and beta-carotene reduced AIP and inflammation by preventing LDL oxidation.

Subtercola endophyticus sp. nov., a cold-adapted bacterium isolated from Abies koreana

A novel Gram-stain-positive, aerobic bacterial strain, designated AK-R2A1-2 ^T, was isolated from the surface-sterilized needle leaves of an Abies koreana tree. Strain AK-R2A1-2 ^T had 97.3% and 96.7% 16S rRNA gene sequence similarities with Subtercola boreus K300^T and Subtercola lobariae 9583b^T, respectively, but formed a distinct phyletic lineage from these two strains. Growth of strain AK-R2A1-2 ^T was observed at 4–25 °C at pH 5.0–8.0. Strain AK-R2A1-2 ^T contained menaquinone 9 (MK-9) and menaquinone 10 (MK-10) as the predominant respiratory quinones. The major cellular fatty acids were anteiso-C_15:0 and summed feature 8 (C_18:1ω7c or/and C_18:1ω6c), and the polar lipids included diphosphatidylglycerol (DPG) and three unknown aminolipids, AKL2, AKL3, and AKL4. The complete genome of strain AK-R2A1-2 ^T was sequenced to understand the genetic basis of its survival at low temperatures. Multiple copies of cold-associated genes involved in cold-active chaperon, stress response, and DNA repair supported survival of the strain at low temperatures. Strain AK-R2A1-2 ^T was also able to significantly improve rice seedling growth under low temperatures. Thus, this strain represents a novel species of the genus Subtercola, and the proposed name is Subtercola endophyticus sp. nov. The type strain is AK-R2A1-2 ^T (= KCTC 49721 ^T = GDMCC 1.2921 ^T).

Relation Between Dietary Carotenoid Intake, Serum Concentration, and Mortality Risk of CKD Patients Among US Adults: National Health and Nutrition Examination Survey 2001–2014

Background

Current evidence on the relationship between carotenoids and chronic kidney disease (CKD) patients are limited and controversial.

Methods

Data were obtained from the Nutrition and Health Examination Survey (NHANES) database and the NHANES Linked Mortality File, both from a nationally representative sample. Dietary intake was assessed through 24-h dietary recall, and information was available both on dietary and serum α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein/zeaxanthin (combined) through the NHANES cycles used. We used multivariable Cox proportional hazards regression models to estimate the risk for all-cause mortality associated with carotene intakes and serum levels, adjusting for potential confounding factors.

Results

Of the 6,095 CKD participants, 1,924 subjects died (mean follow-up time, 8.1 years). After eliminating all the confounding factors, we found that high levels of total carotene (HR = 0.85, 95% CI, 0.75-0.97, P = 0.011) intakes at baseline were significantly associated with a lower risk of death. And the serum concentrations of carotenoid were also showing that a-carotene (HR = 0.77, 95%CI, 0.65–0.92, P = 0.002), beta-cryptoxanthin (HR = 0.83, 95%CI, 0.70–0.98, P = 0.019), lycopene (HR = 0.77, 95% CI, 0.65–0.91, P = 0.002), and lutein + zeaxanthin (HR = 0.82, 95% CI, 0.70–0.96, P = 0.002) was significantly associated with decreased all-cause mortality of CKD patients. The associations remained similar in the sensitivity analyses.

Conclusion

Findings suggest that high-level carotene dietary intake and the serum concentration were associated with a lower risk of mortality in the CKD population.

Macular pigment optical density and its determinants in a Russian population: the ural eye and medical study

PURPOSE

To assess the macular pigment optical density (MPOD) and its associations with ocular and systemic parameters and diseases.

METHODS

The population-based study Ural Eye and Medical Study included 5899 (80.5%) out of 7328 eligible individuals. As part of ophthalmological and systemic examinations, MPOD was measured by reflectometry.

RESULTS

Macular pigment optical density (MPOD) data were available for 4889 (82.9%) individuals (mean age:57.8 ± 10.1 years;range: 40-94). Mean values for MOPD, maximal MOPD, macular pigment (MP) area and MP volume were 0.13 ± 0.04 d.u. (density units), 0.36 ± 0.09 d.u., 60 791 ± 14 826 pixel and 8033 ± 2888 d.u.pixel, respectively. A higher MP density was correlated (regression coefficient r: 0.63) with older age (standardized regression coefficient beta: 0.59; non-standardized regression coefficient B: 0.23; 95% confidence interval (CI): 0.22, 0.23; p < 0.001), female sex (beta: 0.08; B:0.63; 95%CI: 0.44, 0.83; p < 0.001), rural region of habitation (beta: 0.13; B: 1.02; 95%CI: 0.83, 1.22; p < 0.001), lower body mass index (beta: -0.04; B: -0.03; 95%CI: -0.05, 0.01; p = 0.004), lower prevalence of chronic obstructive pulmonary disorder (beta: -0.03; B: -0.43; 95%CI: -0.79, -0.08; p = 0.02), higher erythrocyte sedimentation rate (beta: 0.03; B: 0.01; 95%CI: 0.002, 0.02; p = 0.03), lower leukocyte cell count (beta: -0.04; B: -0.10; 95%CI: -0.16, -0.03; p = 0.003), thinner temporal parafoveal retinal thickness (beta: -0.06; B: -0.01;95%CI: -0.01, -0.003; p < 0.001), thinner central corneal thickness (beta: -0.06; B: -0.006; 95%CI: -0.009, -0.004; p < 0.001), higher prevalence of pseudophakia (beta: 0.09;B:2.08; 95%CI: 1.50, 2.65; p < 0.001) and reticular pseudo drusen (RPD) (beta: 0.03; B: 0.56; 95%CI: 0.13, 0.98; p = 0.01) and lower stage of open-angle glaucoma (beta: -0.03; B: -0.39; 95%CI: -0.74, -0.04; p = 0. 03). Prevalence (p = 0.44; beta: -0.01) and degree (p = 0.70; beta: -0.01) of angle-closure glaucoma, prevalence (p = 0.31; beta: 0.01) of age-related macular degeneration (AMD) without RPD and prevalence (p = 0.95; beta: 0.001) of diabetic retinopathy were not significantly associated with the mean MP density in that model.

CONCLUSIONS

A higher RPD prevalence and lower stage of open-angle glaucoma were ophthalmological disorders associated with a higher MPOD in a multivariable analysis, including parameters of older age, pseudophakia, female sex, rural region, lower body mass index and lower perifoveal retinal thickness.

The Potential Role of Nutrition in Lung Cancer Establishment and Progression

Lung cancer is a devastating disease with a high incidence and low survival rates, so recent studies have focused on analyzing the risk factors that might prevent this disease from developing or have protective/therapeutic effects. Nutrition is an important key factor in the prevention and treatment of lung cancer. Various factors appear to be involved in the development of the latter, such as cigarette smoking or certain external environmental factors. The increase in oxidative stress is therefore an integral part of the carcinogenesis process. The biological role of bioactive factors derived from adipose tissue, mainly adipokines, is implicated in various cancers, and an increasing body of evidence has shown that certain adipocytokines contribute to the development, progression and prognosis of lung cancer. Not all adipokines stimulate tumor growth; in fact, adiponectin inhibits carcinogenesis by regulating both cell growth and the levels of inflammatory cytokines. Adiponectin expression is deregulated in several cancer types. Many nutritional factors have been shown to increase adiponectin levels and therefore could be used as a new therapeutic strategy for combating lung cancer. In addition, foods with antioxidant and anti-inflammatory properties play a key role in the prevention of many human diseases, including lung cancer. The purpose of this review is to analyze the role of diet in lung cancer in order to recommend dietary habit and lifestyle changes to prevent or treat this pathology.

Oxidative Stress-Induced Male Infertility: Role of Antioxidants in Cellular Defense Mechanisms

Male infertility is linked to several environmental and mutagenic factors. Most of these factors, i.e., lifestyle, radiations, and chemical contaminations, work on the fundamental principles of physics, chemistry, and biology. Principally, it may induce oxidative stress (OS) and produce free radicals within the cells. The negative effect of OS may enhance the reactive oxygen species (ROS) levels in male reproductive organs and impair basic functions in a couple's fertility. Evidence suggests that infertile men have significantly increased ROS levels and a reduced antioxidant capacity compared with fertile men. Although, basic spermatic function and fertilizing capacity depend on a delicate balance between physiological activity of ROS and antioxidants to protect from cellular oxidative injury in sperm, that is essential to achieve pregnancy. The ideal oxidation-reduction (REDOX) equilibrium requires a maintenance of a range of ROS concentrations and modulation of antioxidants. For this reason, the chapter focuses on the effects of ROS in sperm functions and the current concepts regarding the benefits of medical management in men with diminished fertility and amelioration of the effect to improve sperm function. Also, this evidence-based study suggests an increasing rate of infertility that poses a global challenge for human health, urging the need of health care professionals to offer a correct diagnosis, comprehension of the process, and an individualized management of the patients.

Carotenoids and Carcinogenesis: Exploring the Antioxidant and Cell Signaling Roles of Carotenoids in the Prevention of Cancer

Carotenoids are lipid soluble pigments found in various fruits and vegetables and are naturally produced in photoautotrophic plants. Various studies have investigated the properties of carotenoids to determine how they are able to mitigate numerous diseases, including cancer. Carotenoids present in human serum, including β-carotene, α-carotene, lycopene, β-cryptoxanthin, zeaxanthin, and lutein have demonstrated the ability to act as anticarcinogenic agents. Prevention of disease is often described to be more effective than treatment; as cancer impacts millions of lives globally, the role of carotenoids in the prevention of oncogenesis for numerous types of cancers have been extensively researched. This review provides an in-depth analysis of the structure and properties of carotenoids, as well as the identified and potential mechanisms by which carotenoids can act as a chemopreventative agent.

Protective Effect of Carotenoid Extract from Orange-Fleshed Sweet Potato on Gastric Ulcer in Mice by Inhibition of NO, IL-6 and PGE2 Production

Ipomoea batatas (L.) Lam., Convolvulaceae is widely distributed in Asian areas from tropical to warm-temperature regions. Their tubers are known for their antioxidant, anti-bacterial, anti-diabetic, wound healing, anti-inflammatory, and anti-ulcer activities. The preventive and therapeutic effects of orange-fleshed sweet potato on gastric ulcers have not been investigated. In this study, the carotenoid extract (CE) of orange-fleshed sweet potato was found to protect against gastric ulcers induced by HCl/ethanol in mice. The anti-inflammatory and antioxidant activities of the carotenoid pigment extract were also evaluated as possible evidence of their protective effects. Administration of CE reduced gastric ulcers. Oral administration of CE (100 mg/kg) protected against gastric ulcers by 78.1%, similar to the positive control, sucralfate (77.5%). CE showed potent reducing power and decreased nitric oxide production in a mouse macrophage cell line, RAW 264.7, in a concentration-dependent manner. The production of the inflammatory cytokine interleukin-6 and prostaglandin E₂ was also reduced by CE in a dose-dependent manner. The high carotenoid content of orange-fleshed sweet potato could play a role in its protective effect against gastric ulcers. This result suggests the possibility of developing functional products using this nutrient-fortified material.

How microbiological tests reflect bacterial pathogenesis and host adaptation

Historically, clinical microbiological laboratories have often relied on isolation of pure cultures and phenotypic testing to identify microorganisms. These clinical tests are often based on specific biochemical reactions, growth characteristics, colony morphology, and other physiological aspects. The features used for identification in clinical laboratories are highly conserved and specific for a given group of microbes. We speculate that these features might be the result of evolutionary selection and thus may reflect aspects of the life cycle of the organism and pathogenesis. Indeed, several of the metabolic pathways targeted by diagnostic tests in some cases may represent mechanisms for host colonization or pathogenesis. Examples include, but are not restricted to, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella enterica, Shigella spp., and enteroinvasive Escherichia coli (EIEC). Here, we provide an overview of how some common tests reflect molecular mechanisms of bacterial pathogenesis.

Conformational polymorphs of isotretinoin and their impact on physicochemical and biological properties

Isotretinoin is the first-line drug for treatment of severe acne. Only one polymorph was reported even though it has been launched for nearly 40 years, and its clinic application was however limited by its stability and solubility challenges. In our study, two new polymorphs of isotretinoin were discovered and fully characterized. The transformation relationships between these solid forms were fully discussed, and a visible color change during single-crystal-to-single-crystal phase transition with the conformational change was investigated. Form II is determined to be thermodynamic stable form at room temperature, but metastable form at body temperature. The results show that form II is an ideal solid state possessing both superior thermal stability (60℃, open air) and higher absorption once delivered into body. The thermal stability can be associated with the crystal structure such as torsion angle. The relative bioavailability of form II is higher than form I as expected, and the bioavailability of form II formulation is about 2 times as that of the marketed form I capsule. Therefore, form II formulation could provide an alternative for better performing isotretinoin.

Halophilic Carotenoids and Breast Cancer: From Salt Marshes to Biomedicine

Breast cancer is the leading cause of death among women worldwide. Over the years, oxidative stress has been linked to the onset and progression of cancer. In addition to the classical histological classification, breast carcinomas are classified into phenotypes according to hormone receptors (estrogen receptor-RE-/progesterone receptor-PR) and growth factor receptor (human epidermal growth factor receptor-HER2) expression. Luminal tumors (ER/PR-positive/HER2-negative) are present in older patients with a better outcome. However, patients with HER2-positive or triple-negative breast cancer (TNBC) (ER/PR/HER2-negative) subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Therefore, new alternative therapies have become an urgent clinical need. In recent years, anticancer agents based on natural products have been receiving huge interest. In particular, carotenoids are natural compounds present in fruits and vegetables, but algae, bacteria, and archaea also produce them. The antioxidant properties of carotenoids have been studied during the last years due to their potential in preventing and treating multiple diseases, including cancer. Although the effect of carotenoids on breast cancer during in vitro and in vivo studies is promising, clinical trials are still inconclusive. The haloarchaeal carotenoid bacterioruberin holds great promise to the future of biomedicine due to its particular structure, and antioxidant activity. However, much work remains to be performed to draw firm conclusions. This review summarizes the current knowledge on pre-clinical and clinical analysis on the use of carotenoids as chemopreventive and chemotherapeutic agents in breast cancer, highlighting the most recent results regarding the use of bacterioruberin from haloarchaea.

Apocarotenals of Phenolic Carotenoids for Superior Antioxidant Activities

A series of para-phenolic carotenes 1 with ortho- and meta-substitutions were respectively prepared utilizing the benzenesulfonyl protection method, which demonstrated the importance of the ring substituents on their effective conjugation, evaluated by their UV absorption values. The corresponding apo-12'-carotenals 2 were devised to improve the conjugation effect of the para-phenolic radical with the polyene chain by the conjugated aldehyde group. Apo-12'-carotenals 2b and 2c without ortho-substituents exhibited superior antioxidant activities to their corresponding symmetrical carotenes 1 as well as β-carotene and apo-12'-β-carotenal in 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assays.

Ecological effects on female bill colour explain plastic sexual dichromatism in a mutually-ornamented bird

Sex differences in ornamentation are common and, in species with conventional sex roles, are generally thought of as stable, due to stronger sexual selection on males. Yet, especially in gregarious species, ornaments can also have non-sexual social functions, raising the possibility that observed sex differences in ornamentation are plastic. For example, females may invest in costly ornamentation more plastically, to protect body and reproductive ability in more adverse ecological conditions. We tested this hypothesis with experimental work on the mutually-ornamented common waxbill (Estrilda astrild), supplementing their diets either with pigmentary (lutein, a carotenoid) or non-pigmentary (vitamin E) antioxidants, or alleviating winter cold temperature. We found that both lutein and vitamin E supplementation increased red bill colour saturation in females, reaching the same mean saturation as males, which supports the hypothesis that female bill colour is more sensitive to environmental or physiological conditions. The effect of vitamin E, a non-pigment antioxidant, suggests that carotenoids were released from their antioxidant functions. Alleviating winter cold did not increase bill colour saturation in either sex, but increased the stability of female bill colour over time, suggesting that female investment in bill colour is sensitive to cold-mediated stress. Together, results show that waxbill bill sexual dichromatism is not stable. Instead, sexual dichromatism can be modulated, and even disappear completely, due to ecology-mediated plastic adjustments in female bill colour.

Environmental and Nutritional Determinants of Macular Pigment in a Mexican Population

Purpose

The carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin deposit at the macula as macular pigment (MP) and provide visual benefits and protection against macular diseases. The present study investigated MP, its nutritional and environmental determinants, and its constituent carotenoids in serum from a Mexican sample, in healthy participants and with metabolic diseases. Additionally, we compared these variables with an Irish sample.

Methods

MP was measured in 215 subjects from a rural community in Mexico with dual-wavelength autofluorescence imaging reported as MP optical volume (MPOV). Dietary intake and serum concentrations of L and Z were evaluated.

Results

The mean MPOV was 8429 (95% confidence interval, 8060-8797); range. 1171-15,976. The mean L and Z serum concentrations were 0.25 ± 0.15 µmol/L and 0.09 ± 0.04 µmol/L, respectively. The MPOV was positively correlated with L and Z serum concentrations (r = 0.347; P < 0.001 and r = 0.311; P < 0.001, respectively), but not with L + Z dietary estimates. Subjects with daily sunlight exposure of more than 50% were found to have significantly higher MPOV than those with less than 50% (P = 0.005). MPOV and serum concentrations of L and Z were significantly higher in the Mexican sample compared with the Irish sample, but this difference was not reflected in dietary analysis.

Conclusions

These new data from a Mexican sample provide evidence of the multifactorial interactions and environmental determinants of MP such as sunlight exposure and dietary patterns. These findings will be essential for future studies in Mexico for eye health, visual function, and ocular pathology.

MMP-9 and IL-1β as Targets for Diatoxanthin and Related Microalgal Pigments: Potential Chemopreventive and Photoprotective Agents

Photochemoprevention can be a valuable approach to counteract the damaging effects of environmental stressors (e.g., UV radiations) on the skin. Pigments are bioactive molecules, greatly attractive for biotechnological purposes, and with promising applications for human health. In this context, marine microalgae are a valuable alternative and eco-sustainable source of pigments that still need to be taken advantage of. In this study, a comparative in vitro photochemopreventive effects of twenty marine pigments on carcinogenic melanoma model cell B16F0 from UV-induced injury was setup. Pigment modulation of the intracellular reactive oxygen species (ROS) concentration and extracellular release of nitric oxide (NO) was investigated. At the cell signaling level, interleukin 1-β (IL-1β) and matrix metallopeptidase 9 protein (MMP-9) protein expression was examined. These processes are known to be involved in the signaling pathway, from UV stress to cancer induction. Diatoxanthin resulted the best performing pigment in lowering MMP-9 levels and was able to strongly lower IL-1β. This study highlights the pronounced bioactivity of the exclusively aquatic carotenoid diatoxanthin, among the others. It is suggested increasing research efforts on this molecule, emphasizing that a deeper integration of plant ecophysiological studies into a biotechnological context could improve the exploration and exploitation of bioactive natural products.

The Implication of Reactive Oxygen Species and Antioxidants in Knee Osteoarthritis

Knee osteoarthritis (KOA) is a chronic multifactorial pathology and a current and essential challenge for public health, with a negative impact on the geriatric patient's quality of life. The pathophysiology is not fully known; therefore, no specific treatment has been found to date. The increase in the number of newly diagnosed cases of KOA is worrying, and it is essential to reduce the risk factors and detect those with a protective role in this context. The destructive effects of free radicals consist of the acceleration of chondrosenescence and apoptosis. Among other risk factors, the influence of redox imbalance on the homeostasis of the osteoarticular system is highlighted. The evolution of KOA can be correlated with oxidative stress markers or antioxidant status. These factors reveal the importance of maintaining a redox balance for the joints and the whole body's health, emphasizing the importance of an individualized therapeutic approach based on antioxidant effects. This paper aims to present an updated picture of the implications of reactive oxygen species (ROS) in KOA from pathophysiological and biochemical perspectives, focusing on antioxidant systems that could establish the premises for appropriate treatment to restore the redox balance and improve the condition of patients with KOA.