β-Carotene in the human body: metabolic bioactivation pathways - from digestion to tissue distribution and excretion

Role of vitamin A on the ocular surface

Vitamin A is an essential fat-soluble vitamin that cannot be endogenously synthesized by the human body. Retinoic acid (RA) is the biologically active form of vitamin A. Utilizing both nuclear and non-nuclear receptor-mediated pathways, RA plays a crucial role in regulating various biological processes, including apoptosis, differentiation, and anti-inflammatory properties within the cornea and conjunctiva. In addition, RA has been demonstrated to exert a significant influence on anti-tumor mechanisms. Disruption of RA signaling can result in corneal defects, anophthalmia, and microphthalmia. However, the beneficial effects of RA are only observed when it is administered at appropriate dosages, and higher doses have an adverse impact. Ocular abnormalities are often early indicators of a vitamin A deficiency. The lacrimal gland secretes vitamin A onto the ocular surface, where it is metabolized into RA via two sequential steps. This article provides a comprehensive overview of how vitamin A is transformed and transported from the intestine to the ocular surface, ultimately contributing to the maintenance of the normal physiological function of the ocular surface.

The biochemical effects of carotenoids in orange carrots on the colonic proteome in a mouse model of diet-induced obesity

Introduction

Carotenoids are naturally occurring pigments in plants and are responsible for the orange, yellow, and red color of fruits and vegetables. Carrots are one of the primary dietary sources of carotenoids. The biological activities of carotenoids in higher organisms, including their immunomodulatory activities, are well documented in most tissues but not the large intestine. The gastrointestinal barrier acts as a line of defense against the systemic invasion of pathogenic bacteria, especially at the colonic level.

Methods

To test whether carotenoids in orange carrots can alleviate obesity-associated gut inflammation and strengthen the intestinal barrier function, male C57BL/6J mice were randomized to one of four experimental diets for 20 weeks (n = 20 animals/group): Low-fat diet (LFD, 10% calories from fat), high-fat diet (HFD, 45% calories from fat), HFD with white carrot powder (HFD+WC), or HFD with orange carrot powder (HFD + OC). Colon tissues were harvested to analyze the biochemical effects of carotenoids in carrots. The distal sections were subjected to isobaric labeling-based quantitative proteomics in which tryptic peptides were labeled with tandem mass tags, followed by fractionation and LC-MS/MS analysis in an Orbitrap Eclipse Tribrid instrument.

Results

High-performance liquid chromatography results revealed that the HFD+WC pellets were carotenoid-deficient, and the HFD+OC pellets contained high concentrations of provitamin A carotenoids, specifically α-carotene and β-carotene. As a result of the quantitative proteomics, a total of 4410 differentially expressed proteins were identified. Intestinal barrier-associated proteins were highly upregulated in the HFD+OC group, particularly mucin-2 (MUC-2). Upon closer investigation into mucosal activity, other proteins related to MUC-2 functionality and tight junction management were upregulated by the HFD+OC dietary intervention.

Discussion

Collectively, our findings suggest that carotenoid-rich foods can prevent high-fat diet-induced intestinal barrier disruption by promoting colonic mucus synthesis and secretion in mammalian organisms. Data are available via ProteomeXchange with identifier PXD054150.

Advancing triage of acute lymphoblastic leukaemia subtypes diagnosis: label-free Raman spectroscopy for precise single-cell phenotyping and subtype classification

Acute lymphoblastic leukaemia (ALL) is a complex disease in pediatric oncology, necessitating accurate diagnostic strategies for effective treatment planning. The ability to differentiate between B-cell ALL (B-ALL) and T-cell ALL (T-ALL) is crucial for targeted interventions. However, current diagnostic methods are time-consuming and require rapid, dependable tests. This study explores the potential of label-free Raman imaging coupled with chemometrics for rapid blast phenotyping of B-ALL and T-ALL. Our findings demonstrate the efficacy of Raman spectroscopy in sensitively and specifically screening and classifying ALL, as well as its rapidity and reliability. The obtained molecular information allows for label-free and precise leukaemia diagnosis at the single-cell level, surpassing the capabilities of traditional diagnostic techniques. Raman spectra of cancer cells reveal distinctive molecular signatures, specifically heightened protein and nucleic acid content, revealing molecular signatures unique to leukemic phenotypes. Based on that, they could be distinguished from each other and their normal B and T lymphocyte counterparts. This research underscores the analytical power of Raman spectroscopy, positioning it as a valuable tool for identifying and classifying pediatric ALL subtypes. The potential translational applications in clinical practice offer a promising avenue for an expedited and accurate leukaemia diagnosis, paving the way for more targeted and personalised therapeutic approaches.

Clinical rationale for dietary lutein supplementation in long COVID and mRNA vaccine injury syndromes

Lutein, a plant-derived xanthophyl-carotenoid, is an exceptional antioxidant and anti-inflammatory constituent found in food. High dietary intake of lutein is beneficial against eye disease, improves cardiometabolic health, protects from neurodegenerative diseases, and is beneficial for liver, kidney, and respiratory health. Lutein protects against oxidative and nitrosative stress, both of which play a major role in long COVID and mRNA vaccination injury syndromes. Lutein is an important natural agent for therapeutic use against oxidative and nitrosative stress in chronic illnesses such as cardiovascular and neurodegenerative diseases and cancer. It can also potentially inhibit spike protein-induced inflammation. Rich dietary supplementation of lutein, naturally derived in non-biodegradable Extra Virgin Olive Oil (EVOO), can most optimally be used against oxidative and nitrosative stress during post-COVID and mRNA vaccination injury syndromes. Due to its high oleic acid (OA) content, EVOO supports optimal absorption of dietary lutein. The main molecular pathways by which the SARS-CoV-2 spike protein induces pathology, nuclear factor kappa-light-chain-enhancer activated B cells (NF-κB) and activated protein (AP)-1, can be suppressed by lutein. Synergy with other natural compounds for spike protein detoxification is likely.

Retinoid X receptor heterodimers in hepatic function: structural insights and therapeutic potential

Nuclear receptors (NRs) are key regulators of multiple physiological functions and pathological changes in the liver in response to a variety of extracellular signaling changes. Retinoid X receptor (RXR) is a special member of the NRs, which not only responds to cellular signaling independently, but also regulates multiple signaling pathways by forming heterodimers with various other NR. Therefore, RXR is widely involved in hepatic glucose metabolism, lipid metabolism, cholesterol metabolism and bile acid homeostasis as well as hepatic fibrosis. Specific activation of particular dimers regulating physiological and pathological processes may serve as important pharmacological targets. So here we describe the basic information and structural features of the RXR protein and its heterodimers, focusing on the role of RXR heterodimers in a number of physiological processes and pathological imbalances in the liver, to provide a theoretical basis for RXR as a promising drug target.

Association between micronutrients and myopia in American adolescents: evidence from the 2003-2006 National Health and Nutrition Examination Survey

Purpose

To investigate the associations between circulating micronutrients (vitamins A, C, D, E, and carotenoids) and the risk of myopia.

Methods

A total of 1,620 adolescents from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were included. Logistic regression was used to analyze the associations of micronutrients with myopia and high myopia. Restricted cubic spline analysis was employed to assess the potential nonlinear relationships.

Results

Among the 1,620 adolescents, 549 were diagnosed with myopia. After adjusting for multiple covariates, only cis-β-carotene was significantly associated with the risk of myopia (OR 1.19, 95% CI 1.03-1.39) and high myopia (OR 1.44, 95% CI 1.03-2.03). No significant associations were found between vitamins A, D, E, C, α-carotene, trans-β-carotene, lutein zeaxanthin, and myopia. No nonlinear relationships were observed between any of the micronutrients and myopia.

Conclusion

Cis-β-carotene is significantly associated with an increased risk of myopia and high myopia. Further research is needed to understand the underlying mechanisms and potential impact of cis-β-carotene on ocular health.

The low-density lipoprotein receptor contributes to carotenoid homeostasis by regulating tissue uptake and fecal elimination

OBJECTIVE

Carotenoids are lipophilic plant molecules with antioxidant properties. Some carotenoids such as β-carotene also serve as vitamin A precursors, playing a key role in human health. Carotenoids are transported in lipoproteins with other lipids such as cholesterol, however, the mechanisms responsible for carotenoid storage in tissues and their non-enzymatic elimination remain relatively unexplored. The goal of this study was to examine the contribution of the low-density lipoprotein receptor (LDLR) in the bodily distribution and disposal of carotenoids.

METHODS

We employed mice lacking one or both carotenoid-cleaving enzymes as suitable models for carotenoid accumulation. We examined the contribution of LDLR in carotenoid distribution by crossbreeding these mice with Ldlr-/- mice or overexpressing LDLR in the liver.

RESULTS

Our results show that LDLR plays a dual role in carotenoid homeostasis by simultaneously favoring carotenoid storage in the liver and adipose tissue while facilitating their fecal elimination.

CONCLUSIONS

Our results highlight a novel role of the LDLR in carotenoid homeostasis, and unveil a previously unrecognized disposal pathway for these important bioactive molecules.

Inhibitory effects of chlorophyll pigments on the bioaccessibility of β-carotene: Influence of chlorophyll structure and oil matrix

Chlorophylls and β-carotene are fat-soluble phytochemicals in daily diets, while their bioaccessibility interaction remains unknown. Eight dietary chlorophylls and their derivatives (chlorophyll a, chlorophyll b, pheophytin a, pheophytin b, chlorophyllide a, chlorophyllide b, pheophorbide a, pheophorbide b) were combined with β-carotene in six different oil matrices (corn oil, coconut oil, medium-chain triglycerides, peanut oil, olive oil and fish oil) and were subjected to in vitro digestion. Generally, chlorophylls significantly decreased β-carotene bioaccessibility by competitive incorporation into micelles. Dephytylated chlorophylls had a greater inhibitory effect on the micellarization and bioaccessibility of β-carotene compared to phytylated chlorophylls. In their co-digestion system, olive oil group exhibited the smallest particle size and biggest zeta potential in both digesta and micelles. For chlorophylls, the phytol group and their levels are key factors, which was also buttressed by the mice model where additional supplementation of pheophorbide a significantly hindered the accumulation of β-carotene and retinoids compounds.

Carotenoid Supplementation for Alleviating the Symptoms of Alzheimer's Disease

Alzheimer's disease (AD) is characterized by, among other things, dementia and a decline in cognitive performance. In AD, dementia has neurodegenerative features and starts with mild cognitive impairment (MCI). Research indicates that apoptosis and neuronal loss occur in AD, in which oxidative stress plays an important role. Therefore, reducing oxidative stress with antioxidants is a natural strategy to prevent and slow down the progression of AD. Carotenoids are natural pigments commonly found in fruits and vegetables. They include lipophilic carotenes, such as lycopene, α- and β-carotenes, and more polar xanthophylls, for example, lutein, zeaxanthin, canthaxanthin, and β-cryptoxanthin. Carotenoids can cross the blood-brain barrier (BBB) and scavenge free radicals, especially singlet oxygen, which helps prevent the peroxidation of lipids abundant in the brain. As a result, carotenoids have neuroprotective potential. Numerous in vivo and in vitro studies, as well as randomized controlled trials, have mostly confirmed that carotenoids can help prevent neurodegeneration and alleviate cognitive impairment in AD. While carotenoids have not been officially approved as an AD therapy, they are indicated in the diet recommended for AD, including the consumption of products rich in carotenoids. This review summarizes the latest research findings supporting the potential use of carotenoids in preventing and alleviating AD symptoms. A literature review suggests that a diet rich in carotenoids should be promoted to avoid cognitive decline in AD. One of the goals of the food industry should be to encourage the enrichment of food products with functional substances, such as carotenoids, which may reduce the risk of neurodegenerative diseases.

Dynamic and Energetic Aspects of Carotenoids In-and-Around Model Lipid Membranes Revealed in Molecular Modelling

In contrast to plants, humans are unable to synthesise carotenoids and have to obtain them from diet. Carotenoids fulfil several crucial biological functions in the organism; however, due to poor solubility in water, their bioavailability from plant-based food is low. The processes of carotenoid absorption and availability in the human body have been intensively studied. The recent experimental findings concerning these processes are briefly presented in the introductory part of this review, together with a summary of such topics as carotenoid carriers, body transport and tissue delivery, to finally report on molecular-level studies of carotenoid binding by membrane receptors. The main message of the review is contained in the section describing computational investigations of carotenoid intercalation and dynamic behaviour in lipid bilayers. The relevance of these computational studies lies in showing the direct link between the microscopic behaviour of molecules and the characteristics of their macroscopic ensembles. Furthermore, studying the interactions between carotenoids and lipid bilayers, and certainly proteins, on the molecular- and atomic-level using computational methods facilitates the interpretation and explanation of their macroscopic properties and, hopefully, helps to better understand the biological functions of carotenoids.

Carotenoid pattern intake and relation to metabolic status, risk and syndrome, and its components - divergent findings from the ORISCAV-LUX-2 survey

Carotenoids are generally associated with health-beneficial effects; however, their intake patterns related to the metabolic syndrome (MetS) and its components remain controversial. This cross-sectional study investigated associations between dietary intakes of individual carotenoids, fruits and vegetables, and the MetS and its components. Dietary intakes of 1346 participants of the Observation des Risques et de la Santé Cardio-Vasculaire au Luxembourg (ORISCAV-LUX-2) study were investigated by a 174-item FFQ, and carotenoid intake was determined by linking findings using mainly the USDA food databases. Components of MetS and complementary variables, including anthropometric (BMI, waist circumferences and waist:hip ratio) and biological parameters (TAG, HDL-cholesterol, fasting blood glucose and blood pressure), were measured. Logistic (for MetS) and linear multivariable regression models (including assessing MetS as scores) adjusted for various confounders were created. α-and β-Carotene, as well as lutein + zeaxanthin, were inversely associated with MetS (also when it was measured on a continuous scale), reducing the odds for MetS by up to 48 %. However, lycopene, phytoene and phytofluene were rather positively associated with MetS scores and its components, though these adverse effects disappeared, at least for lycopene, when controlling for intakes of tomato-based convenience foods, in line with indicating a rather unhealthy/westernised diet. All these associations remained significant when including fruits and vegetables as confounders, suggesting that carotenoids were related to MetS independently from effects within fruits and vegetables. Thus, a high intake of carotenoids was bidirectionally associated with MetS, its severity, risk and its components, depending on the type of carotenoid. Future investigations are warranted to explore the inverse role that tomato-based carotenoids appear to suggest in relation to the MetS.

Influence of vitamins and food on the fluorescence spectrum of human urine

OBJECTIVES

Fluorescence spectroscopy of human urine is a method with the potential to gain importance as a diagnostic tool in the medical field, e.g., for measuring Coproporphyrin III (CPIII) as an indicator of cancer and acute types of porphyria. Food can change human urine's color, which could influence the urine fluorescence spectrum and the detection of CPIII in urine. To determine if there is a noticeable influence on the urine fluorescence spectrum or on the detection of CPIII in urine, 16 vitamin supplements, and three food items were tested. Such investigation may also prevent false interpretation of measured data.

METHODS

Urine samples were collected before and after (overnight, ca. 8 h) intake of each test substance. Samples were investigated by fluorescence spectrum analysis. At excitation wavelengths from 300 to 500 nm and emission wavelengths from 400 to 700 nm excitation-emission-matrices were measured. Data obtained from urine before intake were compared to the data from overnight urine. Furthermore, the investigation of any interference with the CPIII concentration was performed at an excitation wavelength of 407 ± 3 nm and emission wavelengths of 490-800 nm.

RESULTS

Only vitamin B2, but none of the other tested substances, showed noticeable influence on the urine fluorescence spectrum. None of the tested substances showed noticeable interference with the recovery rate of CPIII.

CONCLUSIONS

The correct interpretation of measured data by fluorescence spectroscopy is possible with the exception if vitamin B2 supplementation was performed; thus, the consumption of vitamin B2 supplements before fluorescence testing of the patient's urine should be avoided and/or must be requested. CPIII concentrations could reliably be measured in all cases.

Research advancements in the maintenance mechanism of Sporidiobolus pararoseus enhancing the quality of soy sauce during fermentation

Soy sauce is a traditional condiment that undergoes microbial fermentation of various ingredients to achieve its desired color, scent, and flavor. Sporidiobolus pararoseus, which is a type of Rhodocerevisiae, shows promising potential as a source of lipids, carotenoids, and enzymes that can enrich the taste and color of soy sauce. However, there is currently a lack of systematic and comprehensive studies on the functions and mechanisms of action of S. pararoseus during soy sauce fermentation. In this review, it is well established that S. pararoseus produces lipids that are abundant in unsaturated fatty acids, particularly oleic acid, as well as various carotenoids, such as β-carotene, torulene, and torularhodin. These pigments are synthesized through the mevalonic acid pathway and possess remarkable antioxidant properties, acting as natural colorants. The synthesis of carotenoids is stimulated by high salt concentrations, which induces oxidative stress caused by NaCl. This stress further activates crucial enzymes involved in carotenoid production, ultimately leading to pigment formation. Moreover, S. pararoseus can produce high-quality enzymes that aid in the efficient utilization of soy sauce substrates during fermentation. Furthermore, this review focused on the impact of S. pararoseus on the color and quality of soy sauce and comprehensively analyzed its characteristics and ingredients. Thus, this review serves as a basis for screening high-quality oleaginous red yeast strains and improving the quality of industrial soy sauce production through the wide application of S. pararoseus.

Analysis of the current vitamin A terminology and dietary regulations from vitamin A1 to vitamin A5

Dietary recommendations on vitamin intake for human food fortification concerning vitamin A in various countries, larger economic zones and international organizations are mainly based on the Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) "Codex Alimentarius standards". The general vitamin A terminology is based on regulations of the International Union of Pure and Applied Chemistry (IUPAC) that are used to describe the involved derivatives. These regulations and terminology were set up in the middle of the last century. Starting with the decade of the 80ies in the 20th century a large improvement of molecular biological methodologies, background physiological mechanisms as well as analytical techniques contributed to a large diversification of this simply claimed vitamin A terminology. Unfortunately, the following terminology and governmental regulations for food fortification are imprecise and non-harmonized. In this article we tried to unravel this terminology for updating terminology, nutritional suggestions and governmental regulations for vitamin A, which are currently based on various uncertainties. According to the current regulations, the newly found vitamin A5/X can be included in the current vitamin A terminology as "vitamin A5" or alternatively or even in parallel as a new vitamin A-independent terminology as "vitamin X". Based on the detailed knowledge of research from the early beginning of general vitamin A pathway identification towards detailed research of the last decades the commonly used and simplified term vitamin A with relevance for governmental recommendations on vitamin intake and food fortification advice was now more correctly sub-categorized to further vitamin A1, and A5 sub-categories with vitamin A1-alcohol as retinol, vitamin A2-alcohol as 3,4-didehydroretinol and vitamin A5-alcohol as 9-cis-13,14-dihydroretinol as their mainly relevant vitamin forms present in the human organism. Here we suggest and advise how the vitamin A terminology and further governmental regulations should be organized depending on a successful unraveling of the organization of the current vitamin A terminology.

Scientific opinion on the tolerable upper intake level for preformed vitamin A and β-carotene

Following two requests from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the revision of the tolerable upper intake level (UL) for preformed vitamin A and β-carotene. Systematic reviews of the literature were conducted for priority adverse health effects of excess vitamin A intake, namely teratogenicity, hepatotoxicity and endpoints related to bone health. Available data did not allow to address whether β-carotene could potentiate preformed vitamin A toxicity. Teratogenicity was selected as the critical effect on which to base the UL for preformed vitamin A. The Panel proposes to retain the UL for preformed vitamin A of 3000 μg RE/day for adults. This UL applies to men and women, including women of child-bearing age, pregnant and lactating women and post-menopausal women. This value was scaled down to other population groups using allometric scaling (body weight0.75), leading to ULs between 600 μg RE/day (infants 4-11 months) and 2600 μg RE/day (adolescents 15-17 years). Based on available intake data, European populations are unlikely to exceed the UL for preformed vitamin A if consumption of liver, offal and products thereof is limited to once per month or less. Women who are planning to become pregnant or who are pregnant are advised not to consume liver products. Lung cancer risk was selected as the critical effect of excess supplemental β-carotene. The available data were not sufficient and suitable to characterise a dose-response relationship and identify a reference point; therefore, no UL could be established. There is no indication that β-carotene intake from the background diet is associated with adverse health effects. Smokers should avoid consuming food supplements containing β-carotene. The use of supplemental β-carotene by the general population should be limited to the purpose of meeting vitamin A requirements.

Defining a vitamin A5/X specific deficiency - vitamin A5/X as a critical dietary factor for mental health

A healthy and balanced diet is an important factor to assure a good functioning of the central and peripheral nervous system. Retinoid X receptor (RXR)-mediated signaling was identified as an important mechanism of transmitting major diet-dependent physiological and nutritional signaling such as the control of myelination and dopamine signalling. Recently, vitamin A5/X, mainly present in vegetables as provitamin A5/X, was identified as a new concept of a vitamin which functions as the nutritional precursor for enabling RXR-mediated signaling. The active form of vitamin A5/X, 9-cis-13,14-dehydroretinoic acid (9CDHRA), induces RXR-activation, thereby acting as the central switch for enabling various heterodimer-RXR-signaling cascades involving various partner heterodimers like the fatty acid and eicosanoid receptors/peroxisome proliferator-activated receptors (PPARs), the cholesterol receptors/liver X receptors (LXRs), the vitamin D receptor (VDR), and the vitamin A(1) receptors/retinoic acid receptors (RARs). Thus, nutritional supply of vitamin A5/X might be a general nutritional-dependent switch for enabling this large cascade of hormonal signaling pathways and thus appears important to guarantee an overall organism homeostasis. RXR-mediated signaling was shown to be dependent on vitamin A5/X with direct effects for beneficial physiological and neuro-protective functions mediated systemically or directly in the brain. In summary, through control of dopamine signaling, amyloid β-clearance, neuro-protection and neuro-inflammation, the vitamin A5/X - RXR - RAR - vitamin A(1)-signaling might be "one of" or even "the" critical factor(s) necessary for good mental health, healthy brain aging, as well as for preventing drug addiction and prevention of a large array of nervous system diseases. Likewise, vitamin A5/X - RXR - non-RAR-dependent signaling relevant for myelination/re-myelination and phagocytosis/brain cleanup will contribute to such regulations too. In this review we discuss the basic scientific background, logical connections and nutritional/pharmacological expert recommendations for the nervous system especially considering the ageing brain.

Investigating genomic prediction strategies for grain carotenoid traits in a tropical/subtropical maize panel

Vitamin A deficiency remains prevalent on a global scale, including in regions where maize constitutes a high percentage of human diets. One solution for alleviating this deficiency has been to increase grain concentrations of provitamin A carotenoids in maize (Zea mays ssp. mays L.)-an example of biofortification. The International Maize and Wheat Improvement Center (CIMMYT) developed a Carotenoid Association Mapping panel of 380 inbred lines adapted to tropical and subtropical environments that have varying grain concentrations of provitamin A and other health-beneficial carotenoids. Several major genes have been identified for these traits, 2 of which have particularly been leveraged in marker-assisted selection. This project assesses the predictive ability of several genomic prediction strategies for maize grain carotenoid traits within and between 4 environments in Mexico. Ridge Regression-Best Linear Unbiased Prediction, Elastic Net, and Reproducing Kernel Hilbert Spaces had high predictive abilities for all tested traits (β-carotene, β-cryptoxanthin, provitamin A, lutein, and zeaxanthin) and outperformed Least Absolute Shrinkage and Selection Operator. Furthermore, predictive abilities were higher when using genome-wide markers rather than only the markers proximal to 2 or 13 genes. These findings suggest that genomic prediction models using genome-wide markers (and assuming equal variance of marker effects) are worthwhile for these traits even though key genes have already been identified, especially if breeding for additional grain carotenoid traits alongside β-carotene. Predictive ability was maintained for all traits except lutein in between-environment prediction. The TASSEL (Trait Analysis by aSSociation, Evolution, and Linkage) Genomic Selection plugin performed as well as other more computationally intensive methods for within-environment prediction. The findings observed herein indicate the utility of genomic prediction methods for these traits and could inform their resource-efficient implementation in biofortification breeding programs.

Deposition and enrichment of carotenoids in livestock products: An overview

A wide range of research has illustrated that carotenoids play a key role in human health through their versatile beneficial biological functions. Traditionally, the majority dietary sources of carotenoids for humans are obtained from vegetables and fruits, however, the contribution of animal-derived foods has attracted more interest in recent years. Livestock products such as eggs, meat, and milk have been considered as the appropriate and unique carriers for the deposition of carotenoids. In addition, with the enrichment of carotenoids, the nutritional quality of these animal-origin foods would be improved as well as the economic value. Here, we offer an overview covering aspects including the physicochemical properties of carotenoids, the situation of carotenoids fortified in livestock products, and the pathways that lead to the deposition of carotenoids in livestock products. The summary of these important nutrients in livestock products will provide references for animal husbandry and human health.

Artificial neural networks optimize the establishment of a Brazilian germplasm core collection of winter squash (Cucurbita moschata D.)

With widespread cultivation, Cucurbita moschata stands out for the carotenoid content of its fruits such as β and α-carotene, components with pronounced provitamin A function and antioxidant activity. C. moschata seed oil has a high monounsaturated fatty acid content and vitamin E, constituting a lipid source of high chemical-nutritional quality. The present study evaluates the agronomic and chemical-nutritional aspects of 91 accessions of C. moschata kept at the BGH-UFV and propose the establishment of a core collection based on multivariate approaches and on the implementation of Artificial Neural Networks (ANNs). ANNs was more efficient in identifying similarity patterns and in organizing the distance between the genotypes in the groups. The averages and variances of traits in the CC formed using a 15% sampling of accessions, were closer to those of the complete collection, particularly for accumulated degree days for flowering, the mass of seeds per fruit, and seed and oil productivity. Establishing the 15% CC, based on the broad characterization of this germplasm, will be crucial to optimize the evaluation and use of promising accessions from this collection in C. moschata breeding programs, especially for traits of high chemical-nutritional importance such as the carotenoid content and the fatty acid profile.

Gastrointestinal genetic reprogramming of vitamin A metabolic pathways in response of Roux-en-Y gastric bypass

Roux-en-Y gastric bypass (RYGB) is one of the most performed bariatric surgical techniques. However, RYGB commonly results, as side effects, in nutritional deficiencies. This study aimed to examine changes in the expression of vitamin A pathway encoding genes in the gastrointestinal tract (GI) and to evaluate the potential mechanisms associated with hypovitaminosis A after RYGB. Intestinal biopsies were obtained through double-balloon endoscopy in 20 women with obesity (age 46.9±6.2 years; body mass index [BMI] 46.5±5.3 kg/m2 [mean±SD]) before and three months after RYGB (BMI, 38.2±4.2 kg/m2). Intestinal mucosal gene microarray analyses were performed in samples using a Human GeneChip 1.0 ST array (Affymetrix). Vitamin A intake was assessed from 7-day food records and serum retinol levels were evaluated by electrochemiluminescence immunoassay. Our results showed the following genes with significant downregulation (p≤0.05): LIPF (-0.60), NPC1L1 (-0.71), BCO1 (-0.45), and RBP4 (-0.13) in the duodenum; CD36 (-0.33), and ISX (-0.43) in the jejunum and BCO1 (-0.29) in the ileum. No significant changes in vitamin A intake were found (784±694 retinol equivalents [RE] pre-operative vs. 809±753 RE post-operative [mean±SD]). Although patients were routinely supplemented with 3500 international units IU/day (equivalent to 1050 μg RE/day) of oral retinol palmitate, serum concentrations were lower in the post-operative when compared to pre-operative period (0.35±0.14 μg/L vs. 0.52±0.33 μg/L, respectively - P=0.07), both within the normal range. After RYGB, the simultaneous change in expression of GI genes, may impair carotenoid metabolism in the enterocytes, formation of nascent chylomicrons and transport of retinol, resulting in lower availability of vitamin A.

Plasma proteome profiling reveals molecular mechanisms underlying the effects of daily consumption of 'Bahia' and 'Cara Cara' orange juices

Orange juice is an important food source of bioactive compounds, mainly the flavanones hesperidin and narirutin. This study aimed to investigate the underlying molecular mechanisms of action of orange juice's health properties by analyzing changes in the plasma proteome of healthy Brazilian volunteers after consuming juices made from 'Bahia' (BOJ-source of flavanones) and 'Cara Cara' (CCOJ-source of flavanones and carotenoids) oranges cultivated in Brazil. We used an untargeted proteomic approach, with a particular emphasis on the juices' effects on blood coagulant activity. We identified 247 differentially expressed proteins, of which 170 significantly increased or decreased after BOJ consumption and 145 after CCOJ. These proteins are involved in 105 processes that can significantly regulate cell adhesion, cell signaling, cell metabolism, inflammation, or others. Bioinformatic analysis evidenced proteins with major cellular regulatory capacity (e.g., FN1 and GAPDH) and predicted transcription factors (TFs) (e.g., SP1 and CEBPA) and miRNAs (e.g., miR-1-3p and miR-615-3p) that could be involved in the regulation of differentially expressed proteins. In-silico docking analyses between flavanone metabolites and TFs evidenced the higher binding capacity of narirutin phase II metabolites with akt1 and p38, interactions that suggest how the expression of genes of differentially expressed proteins were activated or inhibited. Moreover, the study shed light on proteins of coagulation cascade that presented expression modulated by both juices, proposing the modulation of blood coagulant activity as a potential benefit of OJ (mainly CCOJ) consumption. Taken together, this study revealed that BOJ and CCOJ consumption affected plasma proteome in healthy individuals, suggesting potential molecular targets and mechanisms of OJ bioactive compounds in humans.

Carotenoid metabolites, their tissue and blood concentrations in humans and further bioactivity via retinoid receptor-mediated signalling

Many epidemiological studies have emphasised the relation between carotenoid dietary intake and their circulating concentrations and beneficial health effects, such as lower risk of cardiometabolic diseases and cancer. However, there is dispute as to whether the attributed health benefits are due to native carotenoids or whether they are instead induced by their metabolites. Several categories of metabolites have been reported, most notably involving (a) modifications at the cyclohexenyl ring or the polyene chain, such as epoxides and geometric isomers, (b) excentric cleavage metabolites with alcohol-, aldehyde- or carboxylic acid-functional groups or (c) centric cleaved metabolites with additional hydroxyl, aldehyde or carboxyl functionalities, not counting their potential phase-II glucuronidated / sulphated derivatives. Of special interest are the apo-carotenoids, which originate in the intestine and other tissues from carotenoid cleavage by β-carotene oxygenases 1/2 in a symmetrical / non-symmetrical fashion. These are more water soluble and more electrophilic and, therefore, putative candidates for interactions with transcription factors such as NF-kB and Nrf2, as well as ligands for RAR-RXR nuclear receptor interactions. In this review, we discuss in vivo detected apo-carotenoids, their reported tissue concentrations, and potential associated health effects, focusing exclusively on the human situation and based on quantified / semi-quantified carotenoid metabolites proven to be present in humans.

Post-Harvest Atmospheric Pressure and Composition Modify the Concentration and Bioaccessibility of α- and β-Carotene in Carrots and Sweet Potatoes

Provitamin A (proVA) carotenoid synthesis and degradation are strongly influenced by environmental factors, including during post-harvest storage. Hypobaric and hyperbaric storages increase the shelf-life of many crops, but their effects on proVA carotenoids are not known. Our aim was to investigate the effects of modifications of atmospheric pressure and composition on α- and β-carotene concentration and bioaccessibility during the post-harvest storage of carrots and sweet potatoes. Vegetables were stored for 11-14 days at 20 °C in the dark in chambers with modified pressure and O2 concentrations. In carrots, α- and β-carotene concentrations increased significantly during storage, but compared to the control, they were significantly lower in hyperbaria (-23 and -26%, respectively), whereas they did not differ significantly in hypoxia and hypobaria. In sweet potatoes, α- and β-carotene concentrations decreased significantly during storage, but neither hypoxia, hypobaria nor hyperbaria led to any significant change compared to the control. There was a significant increase for carrot α- and β-carotene bioaccessibility in hypobaria and hyperbaria, while there was a significant decrease for sweet potato β-carotene bioaccessibility in hypobaria/hypoxia and normobaria/hypoxia (-45% and -65% vs. control, respectively). Atmospheric pressure and composition during the post-harvest storage of carrots and sweet potatoes modified the concentration and bioaccessibility of proVA carotenoids.

Deposition and bioconversion law of β-carotene in laying hens after long-term supplementation under adequate vitamin A status in the diet

β-Carotene, because it is the precursor of vitamin A and has versatile biological roles, has been applied as a feed additive in the poultry industry for a long time. In this study, we investigated the deposition and bioconversion of β-carotene in laying hens. A total of 600 Hy-line brown laying hens at 40 wk of age were randomly divided into 5 dietary treatments, each group's dietary supplemental levels of β-carotene were 0, 15, 30, 60, 120 mg/kg feed, and the vitamin A levels were all 8,000 IU/kg. After 14-wk trial, samples were collected, then carotenoids and different forms of vitamin A were detected using the novel method developed by our laboratory. We found that dietary β-carotene treatment had no significant effects on laying hens' production performance and egg quality (P > 0.05), except the yolk color. The deposition of β-carotene in the body gradually increased (P < 0.01) with the supplemental dose, whereas the contents of lutein and zeaxanthin decreased (P < 0.05). When the β-carotene supplemental level was above 30 mg/kg in the diet, the different forms of vitamin A in in serum, liver, ovary, and yolks were increased compared to the control group (P < 0.05). However, these indicators decreased when the additional dose was 120 mg/kg. Moreover, the mRNA levels of the genes involved in β-carotene absorption, bioconversion, and negative feedback regulation in duodenal mucosa and liver were upregulated after long-term feeding (P < 0.05). Histological staining of the ovaries indicated that the deposition of β-carotene led to a lower rate of follicle atresia (P < 0.05), and this positive effects may be related to the antioxidant function of β-carotene, which caused a reduction of oxidation products in the ovary (P < 0.05). Altogether, β-carotene could accumulate in laying hens intactly and exert its biological functions in tissue. Meanwhile, a part of β-carotene could also be converted into vitamin A but this bioconversion has an upper limit and negative feedback regulation.

Carotenoids in Health as Studied by Omics-Related Endpoints

Carotenoids have been associated with risk reduction for several chronic diseases, including the association of their dietary intake/circulating levels with reduced incidence of obesity, type 2 diabetes, certain types of cancer, and even lower total mortality. In addition to some carotenoids constituting vitamin A precursors, they are implicated in potential antioxidant effects and pathways related to inflammation and oxidative stress, including transcription factors such as nuclear factor κB and nuclear factor erythroid 2-related factor 2. Carotenoids and metabolites may also interact with nuclear receptors, mainly retinoic acid receptor/retinoid X receptor and peroxisome proliferator-activated receptors, which play a role in the immune system and cellular differentiation. Therefore, a large number of downstream targets are likely influenced by carotenoids, including but not limited to genes and proteins implicated in oxidative stress and inflammation, antioxidation, and cellular differentiation processes. Furthermore, recent studies also propose an association between carotenoid intake and gut microbiota. While all these endpoints could be individually assessed, a more complete/integrative way to determine a multitude of health-related aspects of carotenoids includes (multi)omics-related techniques, especially transcriptomics, proteomics, lipidomics, and metabolomics, as well as metagenomics, measured in a variety of biospecimens including plasma, urine, stool, white blood cells, or other tissue cellular extracts. In this review, we highlight the use of omics technologies to assess health-related effects of carotenoids in mammalian organisms and models.

Metabolic engineering and synthetic biology strategies for producing high-value natural pigments in Microalgae

Microalgae are microorganisms capable of producing bioactive compounds using photosynthesis. Microalgae contain a variety of high value-added natural pigments such as carotenoids, phycobilins, and chlorophylls. These pigments play an important role in many areas such as food, pharmaceuticals, and cosmetics. Natural pigments have a health value that is unmatched by synthetic pigments. However, the current commercial production of natural pigments from microalgae is not able to meet the growing market demand. The use of metabolic engineering and synthetic biological strategies to improve the production performance of microalgal cell factories is essential to promote the large-scale production of high-value pigments from microalgae. This paper reviews the health and economic values, the applications, and the synthesis pathways of microalgal pigments. Overall, this review aims to highlight the latest research progress in metabolic engineering and synthetic biology in constructing engineered strains of microalgae with high-value pigments and the application of CRISPR technology and multi-omics in this context. Finally, we conclude with a discussion on the bottlenecks and challenges of microalgal pigment production and their future development prospects.

RNA-Seq analysis of the pyloric caecum, liver, and muscle reveals molecular mechanisms regulating fillet color in rainbow trout

BACKGROUND

The characteristic pink-reddish color in the salmonids fillet is an important, appealing quality trait for consumers and producers. The color results from diet supplementation with carotenoids, which accounts for up to 20-30% of the feed cost. Pigment retention in the muscle is a highly variable phenotype. In this study, we aimed to understand the molecular basis for the variation in fillet color when rainbow trout (Oncorhynchus mykiss) fish families were fed an Astaxanthin-supplemented diet. We used RNA-Seq to study the transcriptome profile in the pyloric caecum, liver, and muscle from fish families with pink-reddish fillet coloration (red) versus those with lighter pale coloration (white).

RESULTS

More DEGs were identified in the muscle (5,148) and liver (3,180) than in the pyloric caecum (272). Genes involved in lipid/carotenoid metabolism and transport, ribosomal activities, mitochondrial functions, and stress homeostasis were uniquely enriched in the muscle and liver. For instance, the two beta carotene genes (BCO1 and BCO2) were significantly under-represented in the muscle of the red fillet group favoring more carotenoid retention. Enriched genes in the pyloric caecum were involved in intestinal absorption and transport of carotenoids and lipids. In addition, the analysis revealed the modulation of several genes with immune functions in the pyloric caecum, liver, and muscle.

CONCLUSION

The results from this study deepen our understanding of carotenoid dynamics in rainbow trout and can guide us on strategies to improve Astaxanthin retention in the rainbow trout fillet.

Use of Cells, Supplements, and Peptides as Therapeutic Strategies for Modulating Inflammation after Spinal Cord Injury: An Update

Spinal cord injury is a traumatic lesion that causes a catastrophic condition in patients, resulting in neuronal deficit and loss of motor and sensory function. That loss is caused by secondary injury events following mechanical damage, which results in cell death. One of the most important events is inflammation, which activates molecules like proinflammatory cytokines (IL-1β, IFN-γ, and TNF-α) that provoke a toxic environment, inhibiting axonal growth and exacerbating CNS damage. As there is no effective treatment, one of the developed therapies is neuroprotection of the tissue to preserve healthy tissue. Among the strategies that have been developed are the use of cell therapy, the use of peptides, and molecules or supplements that have been shown to favor an anti-inflammatory environment that helps to preserve tissue and cells at the site of injury, thus favoring axonal growth and improved locomotor function. In this review, we will explain some of these strategies used in different animal models of spinal cord injury, their activity as modulators of the immune system, and the benefits they have shown.

Human nutritional relevance and suggested nutritional guidelines for vitamin A5/X and provitamin A5/X

In the last century, vitamin A was identified that included the nutritional relevant vitamin A1 / provitamin A1, as well as the vitamin A2 pathway concept. Globally, nutritional guidelines have focused on vitamin A1 with simplified recommendations and calculations based solely on vitamin A. The vitamin A / provitamin A terminology described vitamin A with respect to acting as a precursor of 11-cis-retinal, the chromophore of the visual pigment, as well as retinoic acid(s), being ligand(s) of the nuclear hormone receptors retinoic acid receptors (RARs) α, β and γ. All-trans-retinoic acid was conclusively shown to be the endogenous RAR ligand, while the concept of its isomer 9-cis-retinoic acid, being "the" endogenous ligand of the retinoid-X receptors (RXRs), remained inconclusive. Recently, 9-cis-13,14-dihydroretinoic acid was conclusively reported as an endogenous RXR ligand, and a direct nutritional precursor was postulated in 2018 and further confirmed by Rühl, Krezel and de Lera in 2021. This was further termed vitamin A5/X / provitamin A5/X. In this review, a new vitamin A5/X / provitamin A5/X concept is conceptualized in parallel to the vitamin A(1) / provitamin A(1) concept for daily dietary intake and towards dietary guidelines, with a focus on the existing national and international regulations for the physiological and nutritional relevance of vitamin A5/X. The aim of this review is to summarize available evidence and to emphasize gaps of knowledge regarding vitamin A5/X, based on new and older studies and proposed future directions as well as to stimulate and propose adapted nutritional regulations.

Nanoparticles Loaded with a Carotenoid-Rich Extract from Cantaloupe Melon Improved Hepatic Retinol Levels in a Diet-Induced Obesity Preclinical Model

The study evaluated the effect of the carotenoid-rich extract from cantaloupe melon (CE) nanoencapsulated in porcine gelatin (EPG) on hepatic retinol concentration and liver damage scores in Wistar rats with obesity induced by high glycemic index and high glycemic load diet (HGLI diet). For 17 days, animals were fed the HGLI diet. They were divided into three groups and treated for 10 days [HGLI diet + water, HGLI diet + CE (12.5 mg/kg), and HGLI diet + EPG (50 mg/kg)]. The groups were evaluated for dietary intake, retinol, weight variation, hematological parameters, fasting glucose, lipid profile, hepatic retinol concentration, AST/ALT ratio, FIB-4 (Fibrosis-4 Index for Liver Fibrosis), and APRI (AST to Platelet Ratio Index) scores to evaluate the effects on the liver. Animals treated with EPG showed a lower dietary intake (p < 0.05). No significant weight change was detected in the evaluated groups (p > 0.05). The EPG-treated group had significantly higher concentrations (p < 0.05) of hepatic retinol [266 (45) μg/g] than the untreated group [186 (23.8) μg/g] and the one treated with CE [175 (8.08) μg/g]. Liver damage assessment scores did not show significant differences, but the lowest means were observed in the group treated with EPG. The nanoencapsulation of the extract rich in beta-carotene promoted reduced food consumption and increased hepatic retinol without causing significant changes in liver damage scores. Thus, EPG is a candidate for future clinical studies to evaluate the beneficial effects of treating diseases involving vitamin A deficiencies.

Development and application of a SFC-DAD-MS/MS method to determine carotenoids and vitamin A in egg yolks from laying hens supplemented with β-carotene

β-Carotene, a provitamin A carotenoid, can be converted into vitamin A in animals' bodies, and can also be accumulated intactly in many animal products. In this study, supercritical fluid chromatography-tandem mass spectrometry was utilized to determine β-carotene and different forms of vitamin A in eggs simultaneously. According to the results, β-carotene contained in yolk reached a plateau after about 2 weeks of supplementation. With an increase in dietary supplement level, the amount of β-carotene gradually increased, as well as slightly changing the yolk color. Moreover, the contents of retinoids including retinol, retinyl propionate, retinyl palmitate and retinyl stearate were also elevated in yolks with the β-carotene additive levels; meanwhile, the lutein and zeaxanthin decreased. On the whole, β-carotene in the diet of laying hens could be partially deposited in egg yolk, and the contents of vitamin A in yolk could be increased due to β-carotene bioconversion.

Is beta-carotene consumption associated with thyroid hormone levels?

The thyroid hormones play a pivotal role in various physiological processes, including growth, metabolism regulation, and reproduction. While non-modifiable factors are known to impact thyroid function, such as genetics and age, nutritional factors are also important. Diets rich in selenium and iodine are conventionally acknowledged to be beneficial for the production and release of thyroid hormones. Recent studies have suggested a potential link between beta-carotene, a precursor to vitamin A (retinol), and thyroid function. Beta-carotene is known for its antioxidant properties and has been shown to play a role in the prevention of various clinical conditions such as cancer and cardiovascular and neurological diseases. However, its impact on thyroid function is still unclear. Some studies have suggested a positive association between beta-carotene levels and thyroid function, while others have found no significant effect. Conversely, the hormone produced by the thyroid gland, thyroxine, enhances the conversion of beta-carotene to retinol. Furthermore, vitamin A derivatives are being explored as potential therapeutic options for thyroid malignancies. In this review, we highlight the mechanisms through which beta-carotene/retinol and thyroid hormones interact and review the findings of clinical studies examining the association between beta-carotene consumption and thyroid hormone levels. Our review underscores the need for further research to clarify the relationship between beta-carotene and thyroid function.

Therapeutic Investigation of Palm Oil Mill Effluent-Derived Beta-Carotene in Streptozotocin-Induced Diabetic Retinopathy via the Regulation of Blood-Retina Barrier Functions

Diabetic retinopathy (DR) primarily progresses into retinal degeneration caused by microvascular dysfunction. The pathophysiology of DR progression is still uncertain. This study investigates the function of beta-carotene (PBC) originating from palm oil mill effluent in the treatment of diabetes in mice. An intraperitoneal injection of streptozotocin (35 mg/kg) was used to induce diabetes, which was then accelerated by an intravitreal (i.vit.) injection of STZ (20 µL on day 7). PBC (50 and 100 mg/kg) and dexamethasone (DEX: 10 mg/kg) were also administered orally (p.o.) for 21 days. At various time intervals, the optomotor response (OMR) and visual-cue function test (VCFT) responses were evaluated. Biomarkers, such as reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARSs), and catalase activity were determined in retinal tissue samples. DR significantly lowers the spatial frequency threshold (SFT) and time spent in the target quadrant (TSTQ), increases the reaching time in the visual-cue platform (RVCP), lowers retinal GSH and catalase activity levels, and elevates TBARS levels. The treatments of PBC and DEX also ameliorate STZ-induced DR alterations. The potential ameliorative activity of PBC in DR is attributed to its anti-diabetic, anti-oxidative, and control of blood-retinal barrier layer properties.

Antioxidants as Protection against Reactive Oxidative Stress in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) belongs to a group of chronic diseases characterised by periods of exacerbation and remission. Despite many studies and observations, its aetiopathogenesis is still not fully understood. The interactions of genetic, immunological, microbiological, and environmental factors can induce disease development and progression, but there is still a lack of information on these mechanisms. One of the components that can increase the risk of occurrence of IBD, as well as disease progression, is oxidative stress. Oxidative stress occurs when there is an imbalance between reactive oxygen species (ROS) and antioxidants. The endogenous and exogenous components that make up the body's antioxidant defence can significantly affect IBD prophylaxis and reduce the risk of exacerbation by neutralising and removing ROS, as well as influencing the inflammatory state.

An ex vivo intestinal absorption model is more effective than an in vitro cell model to characterise absorption of dietary carotenoids following simulated gastrointestinal digestion

To get the most accurate food digestion-related data, and how this affects nutrient absorption, it is critical to carefully simulate human digestion systems using model settings. In this study, the uptake and transepithelial transportation of dietary carotenoids was compared using two different models that have previously been used to assess nutrient availability. The permeability of differentiated Caco-2 cells and murine intestinal tissue were tested using all-trans-β-carotene and lutein prepared in artificial mixed micelles and micellar fraction from orange-fleshed sweet potato (OFSP) gastrointestinal digestion. Transepithelial transport and absorption efficiency were then determined using liquid chromatography tandem-mass spectrometry (LCMS-MS). Results showed that the mean uptake for all-trans-β-carotene in the mouse mucosal tissue was 60.2 ± 3.2% compared to 36.7 ± 2.6% in the Caco-2 cells with the mixed micelles as the test sample. Similarly, the mean uptake was higher in OFSP with 49.4 ± 4.1% following mouse tissue uptake compared to 28.9 ± 4.3% using Caco-2 cells for the same concentration. In relation to the uptake efficiency, the mean percentage uptake for all-trans-β-carotene from artificial mixed micelles was 1.8-fold greater in mouse tissue compared to Caco-2 cells (35.4 ± 1.8% against 19.9 ± 2.6%). Carotenoid uptake reached saturation at 5 µM when assessed with the mouse intestinal cells. These results demonstrate the practicality of employing physiologically relevant models simulating human intestinal absorption processes that compares well with published human in vivo data. When used in combination with the Infogest digestion model, the Ussing chamber model, using murine intestinal tissue, may thus be an efficient predictor of carotenoid bioavailability in simulating human postprandial absorption ex vivo.

Carotenoids and Their Health Benefits as Derived via Their Interactions with Gut Microbiota

Carotenoids have been related to a number of health benefits. Their dietary intake and circulating levels have been associated with a reduced incidence of obesity, diabetes, certain types of cancer, and even lower total mortality. Their potential interaction with the gut microbiota (GM) has been generally overlooked but may be of relevance, as carotenoids largely bypass absorption in the small intestine and are passed on to the colon, where they appear to be in part degraded into unknown metabolites. These may include apo-carotenoids that may have biological effects because of higher aqueous solubility and higher electrophilicity that could better target transcription factors, i.e., NF-κB, PPARγ, and RAR/RXRs. If absorbed in the colon, they could have both local and systemic effects. Certain microbes that may be supplemented were also reported to produce carotenoids in the colon. Although some bactericidal aspects of carotenoids have been shown in vitro, a few studies have also demonstrated a prebiotic-like effect, resulting in bacterial shifts with health-associated properties. Also, stimulation of IgA could play a role in this respect. Carotenoids may further contribute to mucosal and gut barrier health, such as stabilizing tight junctions. This review highlights potential gut-related health-beneficial effects of carotenoids and emphasizes the current research gaps regarding carotenoid-GM interactions.

Effects of different vitamin A supplies on performance and the risk of ketosis in transition cows

This experiment investigated the effects of feeding low and high supplies of vitamin A (VA) during the transition period on plasma metabolites, prevalence of ketosis, and early milk production. In a randomized complete block design, 42 prefresh Holstein cows and 21 heifers were blocked by parity and calving date and assigned to 1 of 3 dietary treatments (n = 21 per treatment unless noted): CON, a transition diet with supplemental VA (75,000 IU/d) to meet the requirement; LVA, a transition diet with no supplemental VA; or HVA, a transition diet receiving supplemental VA (187,500 IU/d) 2.5 times greater than the requirement. Experimental periods were prepartum (-14 d prepartum), postpartum (1 to 30 d in milk), and carryover period (31 to 58 d in milk; common lactating diet with adequate VA was fed). Differences in dry matter intake in the pre- and postpartum periods and milk yield were not detected among treatment. Milk fat, protein, and lactose yields were similar among treatments and not affected by VA. Somatic cell count increased linearly with increasing VA. Body weight and body condition score decreased postpartum, but no VA effect was observed. Plasma retinol concentrations (n = 10 per treatment) decreased at d 2 postpartum and increased as lactation progressed, but the concentrations were unaffected by treatment. Plasma β-carotene (n = 10 per treatment) had a treatment by time interaction and its concentration decreased after parturition and remained low for 2 wk. Plasma fatty acids and β-hydroxybutyrate did not differ among treatments. Milk retinol concentration and yield (n = 10 per treatment) increased as VA supply increased. Segmented neutrophils (%) decreased, and lymphocytes (%) increased in blood with increasing VA supply. In conclusion, providing different supplies of VA did not affect production, mobilization of body fat, and risk of ketosis; however, excessive VA supply may have negatively affected the immune response, in part contributing to increased milk somatic cell counts during early lactation.

Glutathione system enhancement for cardiac protection: pharmacological options against oxidative stress and ferroptosis

The glutathione (GSH) system is considered to be one of the most powerful endogenous antioxidant systems in the cardiovascular system due to its key contribution to detoxifying xenobiotics and scavenging overreactive oxygen species (ROS). Numerous investigations have suggested that disruption of the GSH system is a critical element in the pathogenesis of myocardial injury. Meanwhile, a newly proposed type of cell death, ferroptosis, has been demonstrated to be closely related to the GSH system, which affects the process and outcome of myocardial injury. Moreover, in facing various pathological challenges, the mammalian heart, which possesses high levels of mitochondria and weak antioxidant capacity, is susceptible to oxidant production and oxidative damage. Therefore, targeted enhancement of the GSH system along with prevention of ferroptosis in the myocardium is a promising therapeutic strategy. In this review, we first systematically describe the physiological functions and anabolism of the GSH system, as well as its effects on cardiac injury. Then, we discuss the relationship between the GSH system and ferroptosis in myocardial injury. Moreover, a comprehensive summary of the activation strategies of the GSH system is presented, where we mainly identify several promising herbal monomers, which may provide valuable guidelines for the exploration of new therapeutic approaches.

In vitro bioaccessibility and uptake of β-carotene from encapsulated carotenoids from mango by-products in a coupled gastrointestinal digestion/Caco-2 cell model

β-carotene is a carotenoid with provitamin A activity and other health benefits, which needs to become bioavailable upon oral intake to exert its biological activity. A better understanding of its behaviour and stability in the gastrointestinal tract and means to increase its bioavailability are highly needed. Using an in vitro gastrointestinal digestion method coupled to an intestinal cell model, we explored the stability, gastrointestinal bioaccessibility and cellular uptake of β-carotene from microparticles containing carotenoid extracts derived from mango by-products. Three types of microparticles were tested: one with the carotenoid extract as such, one with added inulin and one with added fructooligosaccharides. Overall, β-carotene was relatively stable during the in vitro digestion, as total recoveries were above 68 %. Prebiotics in the encapsulating material, especially inulin, enhanced the bioaccessibility of β-carotene almost 2-fold compared to microparticles without prebiotics. Likewise, β-carotene bioaccessibility increased proportionally with bile salt concentrations during digestion. Yet, a bile salts level above 10 mM did not contribute markedly to β-carotene bioaccessibility of prebiotic containing microparticles. Cellular uptake experiments with non-filtered gastrointestinal digests yielded higher absolute levels of β-carotene taken up in the epithelial cells as compared to uptake assays with filtered digests. However, the proportional uptake of β-carotene was higher for filtered digests (24 - 31 %) than for non-filtered digests (2 - 8 %). Matrix-dependent carotenoid uptake was only visible in the unfiltered medium, thereby pointing to possible other cellular transport mechanisms of non-micellarized carotenoids, besides the concentration effect. Regardless of a filtration step, inulin-amended microparticles consistently resulted in a higher β-carotene uptake than regular microparticles or FOS-amended microparticles. In conclusion, encapsulation of carotenoid extracts from mango by-products displayed chemical stability and release of a bioaccessible β-carotene fraction upon gastrointestinal digestion. This indicates the potential of the microparticles to be incorporated into functional foods with provitamin A activity.

State-of-the-art methodological investigation of carotenoid activity and metabolism - from organic synthesis via metabolism to biological activity - exemplified by a novel retinoid signalling pathway

Carotenoids are the most abundant lipophilic secondary plant metabolites and their dietary intake has been related to a large number of potential health benefits relevant for humans, including even reduced total mortality. An important feature is their potential to impact oxidative stress and inflammatory pathways, by interacting with transcription factors. For example, they may act as precursors of bioactive derivatives activating nuclear hormone receptor mediated signalling. These bioactive derivatives, originating e.g. from β-carotene, i.e. retinoids / vitamin A, can activate the nuclear hormone receptors RARs (retinoic acid receptors). Due to new analytical insights, various novel metabolic pathways were recently outlined to be mediated via distinct nuclear hormone receptor activating pathways that were predicted and further confirmed. In this article, we describe old and novel metabolic pathways from various carotenoids towards novel ligands of alternative nuclear hormone receptors. However, to fully elucidate these pathways, a larger array of techniques and tools, starting from organic synthesis, lipidomics, reporter models, classical in vitro and in vivo models and further omics-approaches and their statistical evaluation are needed to comprehensively and conclusively study this topic. Thus, we further describe state-of-the-art techniques from A to Ω elucidating carotenoid biological mediated activities and describe in detail required materials and methods needed - in practical protocol form - for the various steps of carotenoid investigations.

Analyzing network pharmacology and molecular docking to clarify Duhuo Jisheng decoction potential mechanism of osteoarthritis mitigation

As a classic remedy for treating Osteoarthritis (OA), Duhuo Jisheng decoction has successfully treated countless patients. Nevertheless, its specific mechanism is unknown. This study explored the active constituents of Duhuo Jisheng decoction and the potential molecular mechanisms for treating OA using a Network Pharmacology approaches. Screening active components and corresponding targets of Duhuo parasite decoction by traditional Chinese medicine systems pharmacology database and analysis platform database. Combining the following databases yielded OA disease targets: GeneCards, DrugBank, PharmGkb, Online Mendelian Inheritance in Man, and therapeutic target database. The interaction analysis of the herb-active ingredient-core target network and protein-protein interaction protein network was constructed by STRING platform and Cytoscape software. Gene ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were carried out. PyMOL and other software were used to verify the molecular docking between the essential active components and the core target. 262 active ingredients were screened, and their main components were quercetin, kaempferol, wogonin, baicalein, and beta-carotene. 108 intersection targets of disease and drug were identified, and their main components were RELA, FOS, STAT3, MAPK14, MAPK1, JUN, and ESR1. Gene ontology analysis showed that the key targets were mainly involved in biological processes such as response to lipopolysaccharide, response to xenobiotic stimulus, and response to nutrient levels. The results of Kyoto Encyclopedia of Genes and Genomes analysis show that the signal pathways include the AGE - RAGE signaling pathway, IL - 17 signaling pathway, TNF signaling pathway, and Toll - like receptor signaling pathway. Molecular docking showed that the main active components of Duhuo parasitic decoction had a good bonding activity with the key targets in treating OA. Duhuo Jisheng decoction can reduce the immune-inflammatory reaction, inhibit apoptosis of chondrocytes, strengthen proliferation and repair of chondrocytes and reduce the inflammatory response in a multi-component-multi-target-multi-pathway way to play a role in the treatment of OA.

β-Carotene regulates glucose transport and insulin resistance in gestational diabetes mellitus by increasing the expression of SHBG

The aim of this work was to study the effect and mechanism of β-carotene on insulin resistance and glucose transport in gestational diabetes mellitus (GDM). Placental tissue and venous blood of 26 GDM patients and 18 normal women were collected. Mice fed a high-fat diet were established as GDM models and treated with β-carotene, from which peripheral blood and placenta tissue were collected. HTR-8/SVneo cells were treated with 10^-7  mol/L insulin for 48 h and established as insulin resistance cell models. The expression of SHBG, GLUT1, GLUT3, GLUT4, IRS-1, IRS-2, PI3Kp85α, and p-CREB/CREB in placental tissues and HTR-8/SVneo cells was detected. Insulin resistance index was calculated from the values of fasting blood glucose and fasting insulin. The glucose consumption of insulin-resistant cells was calculated by detecting the glucose content of the supernatant. The cyclic adenosine monophosphate (cAMP) kit was applied to measure the concentration of cAMP in cells. SHBG was lowly expressed in GDM. β-Carotene treatment upregulated SHBG in the placenta of GDM mice and in insulin-resistant HTR-8/SVneo cells. Overexpression of SHBG upregulated GLUT3, GLUT4, and IRS-1 and enhanced glucose consumption in insulin-resistant cells. β-Carotene treatment promoted the expression of SHBG, GLUT4 and IRS-1 and increased glucose consumption in insulin-resistant cells underexpressing SHBG. Silencing of SHBG decreased the levels of cAMP and pCREB/CREB but β-carotene treatment increased their expression despite SHBG silencing in insulin-resistant cells. β-Carotene promotes glucose transport and inhibits insulin resistance in GDM by increasing the expression of SHBG.

Unconventional Extraction of Total Non-Polar Carotenoids from Pumpkin Pulp and Their Nanoencapsulation

Pumpkin is considered a functional food with beneficial effects on human health due to the presence of interesting bioactives. In this research, the impact of unconventional ultrasound-assisted extraction (UAE) and microwave-assisted extraction techniques on the recovery of total non-polar carotenoids from Cucurbita moschata pulp was investigated. A binary (hexane:isopropanol, 60:40 v/v) and a ternary (hexane:acetone:ethanol, 50:25:25 v/v/v) mixture were tested. The extracts were characterized for their antioxidant properties by in vitro assays, while the carotenoid profiling was determined by high-performance liquid chromatography coupled with a diode array detector. UAE with the binary mixture (30 min, 45 °C) was the most successful extracting technique, taking into consideration all analytical data and their correlations. In parallel, solid lipid nanoparticles (SLN) were optimized for the encapsulation of the extract, using β-carotene as a reference compound. SLN, loaded with up to 1% β-carotene, had dimensions (~350 nm) compatible with increased intestinal absorption. Additionally, the ABTS ((2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay showed that the technological process did not change the antioxidant capacity of β-carotene. These SLN will be used to load an even higher percentage of the extract without affecting their dimensions due to its liquid nature and higher miscibility with the lipid with respect to the solid β-carotene.

Carotenoids in orange carrots mitigate non-alcoholic fatty liver disease progression

Background

Carotenoids are abundant in colored fruits and vegetables. Non-alcoholic fatty liver disease (NAFLD) is a global burden and risk factor for end-stage hepatic diseases. This study aims to compare the anti-NAFLD efficacy between carotenoid-rich and carotenoid-deficient vegetables.

Materials and methods

Male C57BL/6J mice were randomized to one of four experimental diets for 15 weeks (n = 12 animals/group): Low-fat diet (LFD, 10% calories from fat), high-fat diet (HFD, 60% calories from fat), HFD with 20% white carrot powders (HFD + WC), or with 20% orange carrot powders (HFD + OC).

Results

We observed that carotenoids in the orange carrots reduced HFD-induced weight gain, better than white carrots. Histological and triglyceride (TG) analyses revealed significantly decreased HFD-induced hepatic lipid deposition and TG content in the HFD + WC group, which was further reduced in the HFD + OC group. Western blot analysis demonstrated inconsistent changes of fatty acid synthesis-related proteins but significantly improved ACOX-1 and CPT-II, indicating that orange carrot carotenoids had the potential to inhibit NAFLD by improving β-oxidation. Further investigation showed significantly higher mRNA and protein levels of PPARα and its transcription factor activity.

Conclusion

Carotenoid-rich foods may display more potent efficacy in mitigating NAFLD than those with low carotenoid levels.

Mechanisms of carotenoid intestinal absorption and the regulation of dietary lipids: lipid transporter-mediated transintestinal epithelial pathways

Dietary lipids are key ingredients during cooking, processing, and seasoning of carotenoid-rich fruits and vegetables, playing vitals in affecting the absorption and utilization of carotenoids for achieving their health benefits. Besides, dietary lipids have also been extensively studied to construct various delivery systems for carotenoids, such as micro/nanoparticles, micro/nanoemulsions, and liposomes. Currently, the efficacies of these techniques on improving carotenoid bioavailability are often evaluated using the micellization rate or "bioaccessibility" based on in vitro models. However, recent studies have found that dietary lipids may also affect the carotenoid uptake via intestinal epithelial cells and the efflux of intracellular chyle particles via lipid transporters. An increasing number of studies reveal the varied impact of different dietary lipids on the absorption of different carotenoids and some lipids may even have an inhibitory effect. Consequently, it is necessary to clarify the relationship between the addition of dietary lipids and the intestinal absorption of carotenoid to fully understand the role of lipids during this process. This paper first introduces the intestinal absorption mechanism of carotenoids, including the effect of bile salts and lipases on mixed micelles, the types and regulation of lipid transporters, intracellular metabolizing enzymes, and the efflux process of chyle particles. Then, the regulatory mechanism of dietary lipids during intestinal carotenoid absorption is further discussed. Finally, the importance of selecting the dietary lipids for the absorption and utilization of different carotenoids and the design of an efficient delivery carrier are emphasized. This review provides suggestions for precise dietary carotenoid supplementation and offere an important reference for constructing efficient transport carriers for liposoluble nutrients.

Exploration of the Potential Targets and Molecular Mechanism of Carthamus tinctorius L. for Liver Fibrosis Based on Network Pharmacology and Molecular Docking Strategy

Carthamus tinctorius L. (Honghua, HH) is an herbal medicine and functional food widely used to treat chronic liver diseases, including liver fibrosis. By using network pharmacology and molecular docking experiments, the present study aims to determine the bioactive components, potential targets, and molecular mechanisms of HH for treating liver fibrosis. The components of HH were screened from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and literature, and the SwissTargetPrediction database was used to predict the treatment targets of HH. Genecards and DisGeNET databases contained targets for liver fibrosis, and the STRING database provided networks of protein–protein interactions. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using the Database of Annotation, Visualization and Integrated Discovery. The protein–protein interactive network and drug–component–major target–pathway interactive network were visualized and analyzed by Cytoscape software. Finally, Autodock Vina and Discovery Studio software were used for molecular docking Validation. A total of 23 candidate bioactive compounds with 187 treatment targets of HH were acquired from the databases and literature. A total of 121 overlapping targets between HH and liver fibrosis were found to provide the molecular basis for HH on liver fibrosis. Quercetin, beta carotene, and lignan were identified as key components with targeting to ESR1, PIK3CA, and MTOR. HH is engaged in the intervention of various signaling cascades associated with liver fibrosis, such as PI3K/AKT/mTOR pathway, MAPK pathway, and PPAR pathway. In conclusion, HH treats liver fibrosis through multi-component, multi-target, and multi-pathway mechanisms.

Frailty in Aging and the Search for the Optimal Biomarker: A Review

In the context of accelerated aging of the population worldwide, frailty has emerged as one of the main risk factors that can lead to loss of self-sufficiency in older people. This syndrome is defined as a reduced state of physiological reserve and functional capacity. The main diagnostic tools for frailty are based on scales that show deficits compared to their clinical application, such as the Fried frailty phenotype, among others. In this context, it is important to have one or more biomarkers with clinical applicability that can objectively and precisely determine the degree or risk of frailty in older people. The objective of this review was to analyze the biomarkers associated with frailty, classified according to the pathophysiological components of this syndrome (inflammation, coagulation, antioxidants, and liver function, among others). The evidence demonstrates that biomarkers associated with inflammation, oxidative stress, skeletal/cardiac muscle function, and platelet function represent the most promising markers of frailty due to their pathophysiological association with this syndrome. To a lesser extent but with the possibility of greater innovation, biomarkers associated with growth factors, vitamins, amino acids, and miRNAs represent alternatives as markers of this geriatric syndrome. Likewise, the incorporation of artificial intelligence represents an interesting approach to strengthening the diagnosis of frailty by biomarkers.

Disease Prevention and Treatment Using β-Carotene: the Ultimate Provitamin A

Humans being unable to synthesize beta-carotene, the provitamin A, depend on external sources as its supplement. Health benefits and dietary requirements of beta-carotene are interrelated. This orange-red coloured pigment has been enormously examined for its capacity to alleviate several chronic diseases including various types of cancer, cystic fibrosis, as well as COVID-19. However, this class of phytoconstituents has witnessed a broad research gap due to several twin conclusions that have been reported. Natural sources for these compounds along with their extraction methods have been mentioned. The current communication aims at contributing to the global scientific literature on beta-carotene’s application in prevention and treatment of lifestyle diseases.