Carotenoids Diet: Digestion, Gut Microbiota Modulation, and Inflammatory Diseases

Lycopene in male infertility

Male infertility is a major concern around the world, and efforts to find effective therapies to improve reproductive results are continuing. Factors such as genetics, hormonal disorders, lifestyle, and environmental pollutants have been mentioned as the pathoetiology of male infertility. The treatment of male infertility is far from optimal despite the recent signs of progress provided by assisted reproductive technology. Therefore, many efforts are being made to improve the therapeutical approaches to male infertility, which generally target the factors involved in the pathophysiology of the disease. Lycopene is a naturally occurring pigment belonging to the carotenoid family, which imparts a vibrant red color to various fruits and vegetables. It is widely assumed that lycopene may be an optimal option for the improvement of male fertility, however, the verification its therapeutic potential in male infertility has not been comprehensively reviewed. The study discusses the ability of lycopene to improve semen parameters, including sperm morphology, and motility which are important determinants of male reproductive health. Moreover, lycopene's capacity to regulate sex hormones, such as testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which play crucial roles in sperm production and maturation is explained. Additionally, lycopene effects on specific signaling pathways involved in male fertility, including prokineticin-2 (PROK2) and PI3K/Akt pathways, that influence sperm function are clarified. Furthermore, the impacts of lycopene as a potent antioxidant in defending against oxidative stress, a leading cause of male infertility, are presented. Overall, the results indicate that lycopene may have beneficial effects on improving male fertility by increasing sperm parameters, modulating sex hormones and signaling pathways, and providing antioxidant protection. Due to limited reports, additional clinical data is required to confirm the positive effects of lycopene on male fertility in humans.

Carotenoids Improve Obesity and Fatty Liver Disease via Gut Microbiota: A Narrative Review

Carotenoids are natural micronutrients found in plants and microorganisms, but not synthesized by animals. Carotenoids show various biological activities, including antioxidant properties, regulation of cell growth, and modulation of gene expression and immune responses. The rising global incidence of fatty liver disease (FLD) and obesity highlights the importance of carotenoids in chronic progressive conditions. Gut microbiota (GM) dysbiosis is associated with the development and progression of obesity and FLD due to the effects of metabolites such as lipopolysaccharide (LPS), bile acids (BAs), and short-chain fatty acids (SCFAs). Furthermore, GM may affect intestinal barrier integrity. This review evaluates the potential impact of carotenoids on GM and intestinal barrier function, and their subsequent effects on obesity and FLD. We searched through a wide range of databases, such as Web of Science, Scopus, EMBASE, and PubMed, to collect data for our non-systematic review of English literature. Carotenoids such as lycopene, zeaxanthin, fucoxanthin, capsanthin, astaxanthin, and lutein can regulate GM composition and improve obesity and FLD by affecting energy expenditure, food intake, lipid profile, liver fat deposition, liver enzymes, inflammatory markers, glucose homeostasis, and bile acids. These carotenoids improve obesity and FLD through GM metabolites such as SCFAs and LPS. Our findings show that dietary supplementation of lycopene, zeaxanthin, fucoxanthin, capsanthin, astaxanthin, and lutein can positively affect obesity and FLD by regulating GM and intestinal barrier integrity.

The bioactivities and biotechnological production approaches of carotenoids derived from microalgae and cyanobacteria

Microalgae and cyanobacteria are a rich source of carotenoids that are well known for their potent bioactivities, including antioxidant, anti-cancer, anti-proliferative, anti-inflammatory, and anti-obesity properties. Recently, many interests have also been focused on the biological activities of these microalgae/cyanobacteria-derived carotenoids, such as fucoxanthin and β-carotene potential to be the salutary nutraceuticals, on treating or preventing human common diseases (e.g., cancers). This is due to their special chemical structures that demonstrate unique bioactive functions, in which the biologically active discrepancies might attribute to the different spatial configurations of their molecules. In addition, their abundance and bioaccessibilities make them more popularly applied in food and pharmaceutical industries, as compared to the macroalgal/fungal-derived ones. This review is focused on the recent studies on the bioactivities of fucoxanthin and some carotenoids derived from microalgae and cyanobacteria in relationship with human health and diseases, with emphasis on their potential applications as natural antioxidants. Various biotechnological approaches employed to induce the production of these specific carotenoids from the culture of microalgae/cyanobacteria are also critically reviewed. These well-developed and emerging biotechnologies present promise to be applied in food and pharmaceutical industries to facilitate the efficient manufacture of the bioactive carotenoid products derived from microalgae and cyanobacteria.

Unveiling roles of beneficial gut bacteria and optimal diets for health

The gut microbiome plays a pivotal role in human health, influencing digestion, immunity, and disease prevention. Beneficial gut bacteria such as Akkermansia muciniphila, Adlercreutzia equolifaciens, and Christensenella minuta contribute to metabolic regulation and immune support through bioactive metabolites like short-chain fatty acids (SCFAs). Dietary patterns rich in prebiotics, fermented foods, and plant-based bioactive compounds, including polyphenols and flavonoids, promote microbiome diversity and stability. However, challenges such as individual variability, bioavailability, dietary adherence, and the dynamic nature of the gut microbiota remain significant. This review synthesizes current insights into gut bacteria's role in health, emphasizing the mechanisms by which dietary interventions modulate microbiota. Additionally, it highlights advancements in microbiome-targeted therapies and the transformative potential of personalized nutrition, leveraging microbiota profiling and artificial intelligence (AI) to develop tailored dietary strategies for optimizing gut health and mitigating chronic inflammatory disorders. Addressing these challenges requires a multidisciplinary approach that integrates scientific innovation, ethical frameworks, and practical implementation strategies.

Validation by in-vitro digestion and sensory analysis of incorporating vegetable oil encapsulates in cottage cheese

Malnutrition is a global issue linked to energy or nutrient imbalances, often resulting in deficiencies or overweight. Dairy products, rich in macronutrients and micronutrients, are a potential solution. However, processing, storage, and digestion can lead to nutrient loss. To enhance nutritional value, functional ingredients like microencapsulated compounds are used. This study focused on assessing the bioaccessibility of microencapsulated ingredients in cottage cheese, their impact on sensory attributes, and shelf-life. Two microencapsulated ingredients were studied: high oleic palm oil (HOPO), encapsulated using spray drying (SD) and a refractive window (RW) drying technique. The bioaccessibility of these ingredients was evaluated using the INFOGEST in-vitro digestion model. Results showed that HOPO encapsulated via SD in cottage cheese (CSD) preserved oleic and linoleic acids best, and via RW in cottage cheese (CRW) preserve vitamins in 63 % and antioxidants in 96 %. This highlights the effectiveness of microencapsulation techniques in enhancing dairy product functionality and a 72 % of fatty acids release suggesting potential strategies for combating malnutrition through fortified dairy products.

Antioxidant and Anti-Inflammatory Effects of Bioactive Compounds in Atherosclerosis

Atherosclerosis, a chronic inflammatory disease characterized by the accumulation of lipids and immune cells within arterial walls, remains a leading cause of cardiovascular morbidity and mortality worldwide. Oxidative stress and inflammation are central to its pathogenesis, driving endothelial dysfunction, foam cell formation, and plaque instability. Emerging evidence highlights the potential of bioactive compounds with antioxidant and anti-inflammatory properties to mitigate these processes and promote vascular health. This review explores the mechanisms through which bioactive compounds-such as polyphenols, carotenoids, flavonoids, omega-3 fatty acids, coenzyme Q10, and other natural compounds-modulate oxidative stress and inflammation in atherosclerosis. It examines their effects on key molecular pathways, including the inhibition of reactive oxygen species (ROS) production, suppression of nuclear factor-κB (NF-κB), and modulation of inflammatory cytokines. By integrating current knowledge, this review underscores the therapeutic potential of dietary and supplemental bioactive compounds as complementary strategies for managing atherosclerosis, paving the way for future research and clinical applications.

Probiotics and Food Bioactives: Unraveling Their Impact on Gut Microbiome, Inflammation, and Metabolic Health

This review paper delves into the role of probiotics and food bioactives in influencing gut health and overall well-being, within the context of probiotics and food bioactives, emphasizing their roles in modulating inflammation, gut microbiota, and metabolic health. Probiotics are defined as live microorganisms that confer health benefits to the host, primarily through their impact on the gut microbiome; a complex community of microorganisms crucial for maintaining health. The review aims to elucidate how probiotics, incorporated into both traditional and modern food systems, can enhance gut health and address metabolic disorders. It examines the types of probiotics present in various foods and their mechanisms of action, including their effects on immune function and metabolic health. By exploring the links between probiotics and health outcomes such as digestive health, immune support, and mental health, the review identifies specific conditions where probiotics show significant promise. Hurldes such as inconsistencies in research findings, variability in probiotic strains, and dosages are addressed. The paper also suggests future research directions, including the potential for personalized probiotic interventions. The review concludes by summarizing key findings and emphasizing the critical role of probiotics in food systems for promoting overall health and mitigating metabolic diseases.

Advance on the effects of algal carotenoids on inflammatory signaling pathways

The development of inflammation has an indispensable importance in the self-protection of the human body. However, over-inflammation may damage human health, and inflammatory pathways and inflammasomes have a significant impact on the onset of inflammation. Therefore, how to constrain the development of inflammation through inflammatory pathways or inflammasomes becomes a hot research issue. Carotenoids are a natural pigment and an active substance in algae, with anti-inflammatory and antioxidant effects. Many studies have shown that carotenoids have inhibitory effects on the inflammatory pathways and inflammasomes. In this review, we discussed the mechanism of carotenoids targeting those important inflammatory pathways and their effects on common inflammasome NLRP3 and inflammation-related diseases from the perspective of several inflammatory pathways, including p38 MAPK, IL-6/JAK/STAT3, and PI3K, with a focus on the targets and targeting effects of carotenoids on different inflammatory signaling pathways, and at last proposed possible anti-inflammatory targets.

Synergistic Beneficial Effects of Flaxseed (Linum usitatissimum L.) Oil and Olive (Olea europaea L.) Oil Against Metabolic Dysfunction Associated Fatty Liver and Its Complications

Flaxseed and olive oil effectively treat numerous diseases and health conditions, particularly metabolic disorders. Traditional medicine has used both oils for managing cardiovascular disease, diabetes, gastrointestinal dysfunctions, metabolic-dysfunction-associated fatty liver disease (MAFLD), obesity, and more. This review explores the bioactive and polyphenolic compounds in flaxseed and olive oils that provide anti-inflammatory, antioxidant, anti-microbial, hepatoprotective, cardioprotective, antidiabetic, and gastroprotective benefits. Flaxseed oil contains beneficial compounds like alpha-linolenic acid (ALA), lignans, ferulic acid, p-coumaric acid, and phytosterols. It contributes to its therapeutic effects on fatty liver disease and other conditions. Olive oil contains phenolic compounds, including oleic acid, hydroxytyrosol, and tocopherols, which are similarly linked to metabolic health benefits, especially in managing MAFLD. The purpose of this review is to elucidate the mechanisms of action of these bioactive compounds, highlighting their potential in managing various metabolic diseases.

Association between serum carotenoids and hyperuricemia: a cross-sectional study based on NHANES 2001-2006

Purpose

This study aims to investigate the association between serum carotenoids and hyperuricemia.

Methods

Data were sourced from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2006. Hyperuricemia was defined as serum uric acid (UA) levels of ≥7 mg/dL for males and ≥ 6 mg/dL for females. Serum carotenoid levels were measured using high-performance liquid chromatography. Multivariate linear regression was used to analyze the correlation between serum carotenoids and UA levels. Multivariate logistic regression and restricted cubic spline (RCS) analyses were performed to explore the potential association between serum carotenoids and hyperuricemia. Additionally, subgroup and interaction analyses were conducted to determine variations across different population groups.

Result

This cross-sectional study included 13,561 participants. Multivariate linear regression analysis revealed that higher levels of serum carotenoids were correlated with lower UA levels. Specifically, the beta coefficients (β) and 95% confidence intervals (CIs) were as follows: α-carotene (-0.23 [-0.31, -0.15]), β-carotene (-0.30 [-0.38, -0.21]), β-cryptoxanthin (-0.17 [-0.25, -0.09]), lutein/zeaxanthin (-0.12 [-0.20, -0.04]), and total serum carotenoids (-0.25 [-0.33,-0.16]). However, lycopene showed no significant correlation with UA (-0.01 [-0.09, 0.08]). Multivariate logistic regression analysis indicates a significant inverse association between serum carotenoids and the risk of hyperuricemia. The odds ratios (ORs) and 95%CIs were as follows: α-carotene (0.61 [0.49, 0.77]), β-carotene (0.67 [0.51, 0.86]), β-cryptoxanthin (0.69 [0.51, 0.88]), lutein/zeaxanthin (0.72 [0.56, 0.97]), lycopene (0.82 [0.67, 1.00]) and total serum carotenoids (0.73 [0.57, 0.92]). RCS analysis indicated a potential nonlinear relationship between lycopene and hyperuricemia, with an inflection point at 33.45 μg/dL. Subgroup and interaction analyses demonstrated that the inverse association remained consistent across various demographic groups.

Conclusion

This study found that higher serum carotenoid levels are associated with lower UA levels and reduced risk of hyperuricemia. Notably, while lycopene was associated with reduced hyperuricemia risk, its effect showed some heterogeneity.

Shaping the bioactive potential, health-promoting properties, and bioavailability of o/w nanoemulsions by modulating the dose of a carotenoid preparation isolated from Calendula officinalis L

The use of nanotechnology in food production (in particular protein base nanoemulsion) is a solution that is gaining popularity, which allows to design of smart food with targeted health-promoting properties. This study aimed to assess the impact of the dose of the phytochemical extract (1%; 3%; 5% w/w) comprising isolated lipophilic compounds from Calendula officinalis L. on selected physicochemical properties of the emulsion, antioxidant, antidiabetic and antiaging effects, and its impact on carotenoids content and their in vitro bioavailability. The results showed that the use of a 3% extract dosage appears to be optimal for obtaining a nanoemulsion. This variant was characterized by the highest antidiabetic activity and there was no overloading of the nanostructure. Additionally, the use of a pea protein - lipophilic compounds - sunflower/hemp oil matrix to create nanoforms seems to be a promising solution in the context of pro-health properties and bioavailability of bioactive compounds.

Impact of the biomass pretreatment and simulated gastrointestinal digestion on the digestibility and antioxidant activity of microalgae Chlorella vulgaris and Tetraselmis chuii

Chlorella vulgaris and Tetraselmis chuii are two microalgae species already marketed because of their richness in high-value and health-beneficial compounds. Previous studies have demonstrated the biological properties of compounds isolated from both microalgae, although data are not yet available on the impact that pre-treatment and gastrointestinal digestion could exert on these properties. The aim of the present study was to analyze the impact of the biomass pre-treatment (freeze/thaw cycles plus ultrasounds) and simulated gastrointestinal digestion in the bioaccessibility and in vitro antioxidant activity (ABTS, ORAC, Q-FRAP, Q-DPPH) of the released digests. The cell wall from microalgae were susceptible to the pre-treatment and the action of saliva and gastric enzymes, releasing bioactive peptides and phenolic compounds that contributed to the potent antioxidant activity of digests through their radical scavenging and iron reduction capacities. Our findings suggest the potential of these microalgae against oxidative stress-associated diseases at both, intestinal and systemic level.

New findings in the metabolism of the saffron apocarotenoids, crocins and crocetin, by the human gut microbiota

The main constituents of saffron are the apocarotenoids crocins and crocetin, present in the stigmas. Numerous healthy properties, especially those related to the effects on the central nervous system, have been attributed to these compounds but the metabolites responsible for these effects are still unknown. Previous evidences in animal models suggest a role for the gut microbiota in the pharmacokinetics and the neuroprotective effects of these compounds. However, the interaction between these apocarotenoids and the gut microbiota has been poorly studied. In this article, we have thoroughly investigated the batch fermentation of crocin-1 and crocetin (10 μM) with human fecal samples of two donors at different incubation times (0-240 h) using a metabolomic approach. We corroborated a rapid transformation of crocin-1 which looses the glucose molecules through de-glycosylation reactions until its complete transformation into crocetin in 6 hours. A group of intermediate crocins with different degrees of glycosylation were detected in a very short time. Crocetin was further metabolized and new microbial metabolites produced by double-bond reduction and demethylation reactions were identified for the first time: dihydro and tetrahydro crocetins and di-demethyl crocetin. In addition, we detected changes in the levels of the short chain fatty acids valeric acid and hexanoic acid suggesting further structural modifications of crocetin or changes in the catabolic production of these compounds. This research is a pioneering study of the action of the human gut microbiota on the saffron apocarotenoids and goes one step further towards the discovery of metabolites potentially involved in the benefits of saffron.

Reduction in Serum Carotenoid Levels Following One Anastomosis Gastric Bypass

Given the health benefits of carotenoids, it is crucial to evaluate their levels in patients undergoing malabsorptive procedures like one anastomosis gastric bypass (OAGB). This study aimed to assess serum carotenoid levels before and 6 months following OAGB. Prospectively collected data from patients who underwent primary OAGB were analyzed. Data included anthropometrics, dietary intake assessments, and biochemical tests. Serum samples were analyzed for lipid profile and serum carotenoids, including lutein, zeaxanthin, α-carotene, β-carotene, phytofluene, ζ-carotene, and lycopene. Data from 27 patients (median age 47.0 years and 55.6% female) were available before and 6 months post-OAGB. The median pre-surgical BMI was 39.5 kg/m2, and the median excess weight loss at 6 months post-surgery was 63.9%. Significant decreases in all carotenoid levels were observed over time (p < 0.001 for all). A median relative decline of 65.1% in absolute total carotenoid levels and 12.7% in total cholesterol levels were found. No associations were observed between changes in clinical outcomes and carotenoid levels during the study period. This study reveals significant decreases in carotenoid levels within the first 6 months following OAGB. Nutritional intervention studies are needed to explore how incorporating carotenoid-rich foods affects post-surgery carotenoid levels and clinical outcomes.

Natural Pigments Recovery from Food By-Products: Health Benefits towards the Food Industry

Given the health risks associated with synthetic colorants, natural pigments have emerged as a promising alternative. These renewable choices not only provide health benefits but also offer valuable technical and sensory properties to food systems. The effective application of natural colorants, however, requires the optimization of processing conditions, exploration of new sources, and development of novel formulations to ensure stability and maintain their inherent qualities. Several natural pigment sources have been explored to achieve the broad color range desired by consumers. The purpose of this review is to explore the current advances in the obtention and utilization of natural pigments derived from by-products, which possess health-enhancing properties and are extracted through environmentally friendly methods. Moreover, this review provides new insights into the extraction processes, applications, and bioactivities of different types of pigments.

Bioactivity and Bioavailability of Carotenoids Applied in Human Health: Technological Advances and Innovation

This article presents a groundbreaking perspective on carotenoids, focusing on their innovative applications and transformative potential in human health and medicine. Research jointly delves deeper into the bioactivity and bioavailability of carotenoids, revealing therapeutic uses and technological advances that have the potential to revolutionize medical treatments. We explore pioneering therapeutic applications in which carotenoids are used to treat chronic diseases such as cancer, cardiovascular disease, and age-related macular degeneration, offering novel protective mechanisms and innovative therapeutic benefits. Our study also shows cutting-edge technological innovations in carotenoid extraction and bioavailability, including the development of supramolecular carriers and advanced nanotechnology, which dramatically improve the absorption and efficacy of these compounds. These technological advances not only ensure consistent quality but also tailor carotenoid therapies to each patient's health needs, paving the way for personalized medicine. By integrating the latest scientific discoveries and innovative techniques, this research provides a prospective perspective on the clinical applications of carotenoids, establishing a new benchmark for future studies in this field. Our findings underscore the importance of optimizing carotenoid extraction, administration, bioactivity, and bioavailability methods to develop more effective, targeted, and personalized treatments, thus offering visionary insight into their potential in modern medical practices.

Gut Microbiota and Clinical Manifestations in Thai Pediatric Patients with Attention-Deficit Hyperactivity Disorder

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder potentially linked to gut dysbiosis. This comparative cross-sectional study profiled the gut microbiota in 24 treatment-naïve Thai children diagnosed with ADHD and 24 healthy ones matched by age and gender (median age: 7 years). Fecal microbial compositions were genetically analyzed using 16s rRNA gene amplicon sequencing. The study findings indicated no statistically significant differences in microbial diversity between groups, although Firmicutes and Actinobacteria appeared dominant in both groups. Moreover, ADHD patients exhibited enrichment in Alloprevotella, CAG-352, Succinivibrio, and Acidaminococcus genera, while healthy controls had higher levels of Megamonas, Enterobacter, Eubacterium hallii, and Negativibacillus genera. Spearman correlation analysis demonstrated a significant positive association between CAG-352 and inattention and hyperactivity/impulsivity scores, whereas the Eubacterium hallii group and Megamonas exhibited negative correlations with these symptomatology domains. Beta-carotene intake was associated with the Eubacterium hallii group and Succinivibrio: likewise, vitamin B2 intake was associated with Alloprevotella. Additional research should aim to elucidate the underlying mechanisms influencing clinical biomarkers that signify alterations in specific gut microbiome profiles linked to ADHD.

Carotenoids and Intestinal Harmony: Exploring the Link for Health

Carotenoids, prominent lipid-soluble phytochemicals in the human diet, are responsible for vibrant colours in nature and play crucial roles in human health. While they are extensively studied for their antioxidant properties and contributions to vitamin A synthesis, their interactions with the intestinal microbiota (IM) remain poorly understood. In this study, beta (β)-carotene, lutein, lycopene, a mixture of these three pigments, and the alga Osmundea pinnatifida were submitted to simulated gastrointestinal digestion (GID) and evaluated on human faecal samples. The results showed varying effects on IM metabolic dynamics, organic acid production, and microbial composition. Carotenoid exposure influenced glucose metabolism and induced the production of organic acids, notably succinic and acetic acids, compared with the control. Microbial composition analysis revealed shifts in phyla abundance, particularly increased Pseudomonadota. The α-diversity indices demonstrated higher diversity in β-carotene and the pigments' mixture samples, while the β-diversity analysis indicated significant dissimilarity between the control and the carotenoid sample groups. UPLC-qTOF MS analysis suggested dynamic changes in carotenoid compounds during simulated fermentation, with lutein exhibiting distinct mass ion fragmentation patterns. This comprehensive research enhances our understanding of carotenoid-IM interactions, shedding light on potential health implications and the need for tailored interventions for optimal outcomes.

Protective effect of provitamin A dietary carotenoid intake on overweight/obesity and their relation to inflammatory and oxidative stress biomarkers - a case-control study

This investigation assessed associations between dietary carotenoid intake and the odds of overweight/obesity, as well as inflammatory/oxidative stress biomarkers, in 851 participants with overweight/obesity (BMI ≥25 kg m-2) and 754 normal-weight controls. A 124-item food-frequency-questionnaire (FFQ) and food composition databases were employed to estimate carotenoid intake. Binary logistic regressions assessed the association of carotenoid intake with the odds of overweight/obesity, adjusting for several potential confounders. Multiple linear regression models revealed associations between carotenoid intake and biomarkers (anthropometrics, blood lipids, inflammation, antioxidant status). Logistic regression models adjusted for various confounders and fruits and vegetables showed protective associations for provitamin A carotenoids (i.e., β-carotene + α-carotene + β-cryptoxanthin; odds ratio (OR): 0.655, p = 0.041) and astaxanthin (OR: 0.859, p = 0.017). Similarly adjusted multiple linear regressions revealed significant associations between several carotenoids and lower levels of interleukin (IL)-6, IL-1β, and TNF-α and increased IL-10 and total antioxidant capacity. Further analysis revealed that lycopene was significantly associated with increased odds of overweight/obesity (OR: 1.595, p = 0.032) in a model adjusted for various confounders and vegetables (i.e., unadjusted for fruits). A protective association between the sum of provitamin A carotenoid and astaxanthin dietary intake and the odds of having overweight/obesity was found. The findings that carotenoids other than lycopene were not or inversely associated with the odds of overweight/obesity may point toward differentiating effects of various carotenoids or their associations with different food groups. Provitamin A rich food items including fruits and vegetables appear to be a prudent strategy to reduce inflammation and the odds of having overweight/obesity.

Lutein and Zeaxanthin Enhance, Whereas Oxidation, Fructosylation, and Low pH Damage High-Density Lipoprotein Biological Functionality

High-density lipoproteins (HDLs) are key regulators of cellular cholesterol homeostasis but are functionally altered in many chronic diseases. The factors that cause HDL functional loss in chronic disease are not fully understood. It is also unknown what roles antioxidant carotenoids play in protecting HDL against functional loss. The aim of this study was to measure how various disease-associated chemical factors including exposure to (1) Cu2+ ions, (2) hypochlorous acid (HOCL), (3) hydrogen peroxide (H2O2), (4) sialidase, (5) glycosidase, (6) high glucose, (7) high fructose, and (8) acidic pH, and the carotenoid antioxidants (9) lutein and (10) zeaxanthin affect HDL functionality. We hypothesized that some of the modifications would have stronger impacts on HDL particle structure and function than others and that lutein and zeaxanthin would improve HDL function. HDL samples were isolated from generally healthy human plasma and incubated with the corresponding treatments listed above. Cholesterol efflux capacity (CEC), lecithin-cholesterol acyl transferase (LCAT) activity, and paraoxonase-1 (PON1) activity were measured in order to determine changes in HDL functionality. Median HDL particle diameter was increased by acidic pH treatment and reduced by HOCl, high glucose, high fructose, N-glycosidase, and lutein treatments. Acidic pH, oxidation, and fructosylation all reduced HDL CEC, whereas lutein, zeaxanthin, and sialidase treatment improved HDL CEC. LCAT activity was reduced by acidic pH, oxidation, high fructose treatments, and lutein. PON1 activity was reduced by sialidase, glycosidase, H2O2, and fructose and improved by zeaxanthin and lutein treatment. These results show that exposure to oxidizing agents, high fructose, and low pH directly impairs HDL functionality related to cholesterol efflux and particle maturation, whereas deglycosylation impairs HDL antioxidant capacity. On the other hand, the antioxidants lutein and zeaxanthin improve or preserve both HDL cholesterol efflux and antioxidant activity but have no effect on particle maturation.

Effects of Dietary Alfalfa Meal Supplementation on the Growth Performance, Nutrient Apparent Digestibility, Serum Parameters, and Intestinal Microbiota of Raccoon Dogs (Nyctereutes procyonoides)

The raccoon dog (Nyctereutes procyonoides) is a typical omnivore possessing wide dietary adaptability and tolerance to rough feeding, which may be attributed to its intestinal microbiota. The study aimed to investigate the effect of dietary alfalfa meal levels on the growth performance, nutrient apparent digestibility, serum parameters, and intestinal microbiota of raccoon dogs. Sixty raccoon dogs were randomly divided into four dietary treatments containing 0% (AM0), 5% (AM5), 10% (AM10), and 15% (AM15) alfalfa meal for a 60-day experiment. The results showed that compared to raccoon dogs fed the AM0 diet, those fed the AM5 and AM10 diets had no significant difference in growth performance, while those fed the AM15 diet experienced a significant decrease. Raccoon dogs fed the AM5 diet had no significant effect on the nutrient apparent digestibility. Dietary supplementation with alfalfa meal significantly decreased serum urea levels and increased the antioxidant capacity of raccoon dogs. The intestinal microbiome analysis showed that the richness and diversity of colonic microbiota significantly increased in the AM15 group. With the increase in dietary alfalfa meal levels, the relative abundance of fiber-degrading bacteria in the colon of raccoon dogs, such as Treponema, Phascolarctobacterium, and Christensenellaceae R-7 group, increased. However, the relative abundance of pathogenic bacteria, including Anaerobiospirillum, decreased. In conclusion, the inclusion of 5% alfalfa meal in the raccoon dogs' diet had no effect on growth performance, but it exhibited the potential to improve serum antioxidant capacity and intestinal microbiota. This indicates that raccoon dogs have a certain tolerance to the addition of alfalfa meal in their diet.

Understanding mechanisms of antioxidant action in health and disease

Several different reactive oxygen species (ROS) are generated in vivo. They have roles in the development of certain human diseases whilst also performing physiological functions. ROS are counterbalanced by an antioxidant defence network, which functions to modulate ROS levels to allow their physiological roles whilst minimizing the oxidative damage they cause that can contribute to disease development. This Review describes the mechanisms of action of antioxidants synthesized in vivo, antioxidants derived from the human diet and synthetic antioxidants developed as therapeutic agents, with a focus on the gaps in our current knowledge and the approaches needed to close them. The Review also explores the reasons behind the successes and failures of antioxidants in treating or preventing human disease. Antioxidants may have special roles in the gastrointestinal tract, and many lifestyle features known to promote health (especially diet, exercise and the control of blood glucose and cholesterol levels) may be acting, at least in part, by antioxidant mechanisms. Certain reactive sulfur species may be important antioxidants but more accurate determinations of their concentrations in vivo are needed to help assess their contributions.

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.

Plasma Carotenoids and Polyphenols and Their Association with MetS: The Need for Nutritional Interventions

Metabolic syndrome (MetS) is characterized by increased pro-oxidative stress and a chronic inflammation state and their consequent alterations. Several studies have highlighted the protective effect of carotenoids and polyphenols in MetS patients. This study aimed to evaluate the plasma level of selected carotenoids and polyphenols and to determine their relationship with MetS severity, MetS components, and inflammatory markers in Polish adults with metabolic disorders. It was designed as a cross-sectional study. The final study group comprised 275 adults, including 158 women and 117 men. Data were collected on the frequency of consumption of selected food groups. Anthropometric measurements and blood samples were taken to determine the concentration of carotenoids, polyphenols, and indicators (parameters) of metabolic disorders. Plasma concentrations of selected carotenoids and polyphenols were low in adults with MetS. The highest concentrations of carotenoids and polyphenols in the blood were observed for lutein and phenolic acids (including gallic and p-coumaric acids). Nevertheless, a correlation was found between the individual bioactive compounds and MetS components. In terms of the lipid profile, our study showed that the plasma of the selected carotenoids and polyphenols positively correlated with HDL cholesterol (zeaxanthin; total carotenoids), LDL cholesterol (chlorogenic acid), triglycerides (lycopene), and the total cholesterol (kaempferol). We found that the level of CRP as a marker of inflammation negatively correlated with the concentration of zeaxanthin. In our study group, no relationship was found between the dietary antioxidant intensity and the variables studied, which may be attributed to the low frequency of consumption of the sources of bioactive compounds, such as carotenoids and polyphenols, but also to the metabolic disorders. Further research is needed to determine whether these associations are causally related to the metabolic syndrome or are a result of the pathologies of the syndrome or improper diet with a low intake of vegetables and fruit.