Modifying effects of carotenoids on superoxide and nitric oxide generation from stimulated leukocytes

Optimization and Bioactive Evaluation of Bifurcaria bifurcata Antioxidant-Rich Extracts for Functional Food and Pharmaceutical Applications

In recent years, consumers have been increasingly interested in natural, healthier, functional foods, with a focus on sea-based products such as algae. Bifurcaria bifurcata (BB) is a macroalga that belongs to the Phaeophyceae class. These brown algae are recognized as the source of bioactive molecules of great interest to the pharmaceutical and nutraceutical industries. The present work applied response surface methodology to optimize the microwave-assisted extraction of the poorly studied algae. The optimization variables were time, pressure, and solvent composition (ethanol/water) and the response parameters selected were yield, total phenolic and flavonoid content, and the antioxidant profile by evaluating DPPH•+, ABTS•+ scavenging activity, and β-carotene discoloration capacity. The results obtained reveal remarkable bioactivity of the crude extract of BB with positive results as an antioxidant and antimicrobial agent. Furthermore, the BB extract's capacity to inhibit enzymes related to neurodegenerative diseases and its anti-inflammatory and anti-proliferation activity open the possibility of future food or pharmaceutical applications.

Recent Progress in Understanding the Impact of Food Processing and Storage on the Structure-Activity Relationship of Fucoxanthin

Fucoxanthin, a brown algae carotenoid, has attracted great interest because of its numerous biological activities supported by in vitro and in vivo studies. However, its chemical structure is susceptible to alterations when subjected to food processing and storage conditions, such as heat, oxygen, light, and pH changes. Consequently, these conditions lead to the formation of fucoxanthin derivatives, including cis-isomers, apo-fucoxanthinone, apo-fucoxanthinal, fucoxanthinol, epoxides, and hydroxy compounds, collectively known as degradation products. Currently, little information is available regarding the stability and functionality of these fucoxanthin derivatives resulting from food processing and storage. Therefore, enhancing the understanding of the biological effect of fucoxanthin derivatives is crucial for optimizing the utilization of fucoxanthin in various applications and ensuring its efficacy in potential health benefits. To this aim, this review describes the main chemical reactions affecting the stability of fucoxanthin during food processing and storage, facilitating the identification of the major fucoxanthin derivatives. Moreover, recent advancements in the structure-activity relationship of fucoxanthin derivatives will be critically assessed, emphasizing their biological activity. Overall, this review provides a critical updated understanding of the effects of technological processes on fucoxanthin stability and activity that can be helpful for stakeholders when designing processes for food products containing fucoxanthin.

Anti-Obesity and Anti-Inflammatory Synergistic Effects of Green Tea Catechins and Citrus β-Cryptoxanthin Ingestion in Obese Mice

Chronic obesity causes various diseases, leading to an urgent need for its treatment and prevention. Using monosodium-glutamate-induced obesity mice, the present study investigated the synergistic obesity-reducing effects of tea catechins and the antioxidant β-cryptoxanthin present in mandarin oranges. The results show that the obese mice that ingested both tea catechin and β-cryptoxanthin for 4 weeks had a significantly decreased body weight, with no difference in body weight compared with control mice. Moreover, the blood biochemical test results were normal, and the body fat percentage was significantly decreased according to the histopathological analysis. Additionally, the abundance of M1 macrophages, which release pro-inflammatories, was significantly reduced in adipose tissue. Indeed, a significant decrease was detected in M1-macrophage-secreted tumor necrosis factor-alpha levels. Meanwhile, M2 macrophage levels were recovered, and adiponectin, which is released from adipocytes and involved in suppressing metabolic syndrome, was increased. Collectively, these results suggest that the combination of tea catechins and antioxidant foods can alleviate chronic obesity, indicating that a combination of various ingredients in foods might contribute to reducing chronic obesity.

Pharmaceutical and nutraceutical potential of natural bioactive pigment: astaxanthin

Astaxanthin (3,3'-dihydroxy-β,β-carotene-4,4'-dione) is an orange-red, lipophilic keto-carotenoid pigment. It is majorly found in marine ecosystems particularly in aquatic animals such as salmon, shrimp, trout, krill, crayfish, and so on. It is also synthesized in microalgae Heamatococcus pluvialis, Chlorococcum, Chlorella zofingiensis, red yeast Phaffia rhodozyma and bacterium Paracoccus carotinifaciens. Some aquatic and terrestrial creatures regarded as a primary and secondary sources of the astaxanthin producing and accumulating it through their metabolic pathways. Astaxanthin is the powerful antioxidant, nutritional supplement as well as promising therapeutic compound, observed to have activities against different ravaging diseases and disorders. Researchers have reported remarkable bioactivities of astaxanthin against major non-communicable chronic diseases such as cardiovascular diseases, cancer, diabetes, neurodegenerative, and immune disorders. The current review discusses some structural aspects of astaxanthin. It further elaborates its multiple potencies such as antioxidant, anti-inflammatory, anti-proliferative, anti-cancer, anti-obese, anti-diabetic, anti-ageing, anti-TB, anti-viral, anti-COVID 19, neuro-protective, nephro-protective, and fertility-enhancing properties. These potencies make it a more precious entity in the preventions as well as treatments of prevalent systematic diseases and/or disorders. Also, the review is acknowledging and documenting its powerful bioactivities in relation with the pharmaceutical as well as nutraceutical applicability.

Capsanthin induces death in human prostate cancer cell lines by inducing DNA damage

There is a relationship between a person’s diet and the development and prevention of some cancers. Carotenoids are found as various natural pigments in many fruits and vegetables. Studies on carotenoids and their potential roles in carcinogenesis are increasing in importance day by day. In this study, we aimed to determine the cytotoxic and genotoxic effects of capsanthin, a carotenoid compound, in human prostate cancer cell lines.

After different concentrations of capsanthin were applied to human prostate cancer cell lines (LNCaP and PC-3), the effects of the compound on cell viability were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. The single-cell gel electrophoresis (Comet) assay was then used to reveal the genotoxic effects of probable cytotoxic dosages on cell DNA. After the treatments, apoptotic cell death levels were determined by Tunel staining. At high concentrations, capsanthin dramatically reduced PC-3 and LNCaP cell viability (p<0.05). In addition, capsanthin caused DNA damage and apoptotic cell death in the prostate cancer cells. The results show that capsanthin reduces cell viability by causing genotoxicity in prostate cancer cells.

Supercritical fluids and fluid mixtures to obtain high-value compounds from Capsicum peppers

Peppers of the Capsicum genus have a rich nutritional composition and are widely consumed worldwide. Thus, they find numerous applications in the food, pharmaceutical and cosmetic industries. One commercial application is oleoresin production, a nonpolar fraction rich in bioactive compounds, including capsaicinoids and carotenoids. Among the technologies for pepper processing, special attention is given to supercritical fluid technologies, such as supercritical fluid extraction (SFE) with pure solvents and CO2 plus modifiers, and SFE assisted by ultrasound. Supercritical fluid-based processes present advantages over the classical extraction techniques like using less solvents, short extraction times, specificity and scalability. In this review, we present a brief overview of the nutritional aspects of peppers, followed by studies that apply supercritical fluid technologies to produce extracts and concentrate bioactives, besides oleoresin encapsulation. Furthermore, we present related phase equilibrium, cost estimation, and the gaps and needs for the full use of peppers from a sustainable perspective.

Producing fucoxanthin from algae - Recent advances in cultivation strategies and downstream processing

Fucoxanthin, a brown-colored pigment from algae, is gaining much attention from industries and researchers recently due to its numerous potential health benefits, including anti-oxidant, anti-cancer, anti-obesity functions, and so on. Although current commercial production is mainly from brown macroalgae, microalgae with rapid growth rate and much higher fucoxanthin content demonstrated higher potential as the fucoxanthin producer. Factors such as concentration of nitrogen, iron, silicate as well as light intensity and wavelength play a significant role in fucoxanthin biosynthesis from microalgae. Two-stage cultivation approaches have been proposed to maximize the production of fucoxanthin and other valuable metabolites. Sustainable fucoxanthin production can be achieved by using low-cost substrates as a culture medium in an open pond cultivation system utilizing seawater with nutrient recycling. For downstream processing, the integration of novel "green" solvents with other extraction techniques emerged as a promising extraction technique.

Immune-modulation effect of Halocynthia aurantium tunic lipid on RAW264.7 cells

The current study evaluated the immune-regulatory potential of lipid extract from Halocynthia aurantium tunic on macrophage cells. The results showed that H. aurantium lipid is composed of primarily SFA (68.32%), followed by MUFA and PUFA (17.61% and 14.07%, respectively). Halocynthia aurantium lipid dose-dependently modulated the NO and PGE₂ production in RAW264.7 cells without any LPS stimulation. The lipid effectively up-regulated the cytokine expression, including IL-1β, IL-6, and TNF-α in RAW264.7 cells. The COX-2 expression as a key biomarker for inflammation was also significantly increased. Conversely, H. aurantium lipid down-regulated the expression of inflammatory cytokines in LPS-stimulated RAW264.7 cells. Halocynthia aurantium lipid modulated the phosphorylation of NF-κB p-65, p38, ERK, and JNK, indicating that this lipid activated through NF-κB and MAPK pathways. These results provide insight into the immune-regulatory activities of H. aurantium tunic lipid and suggest that H. aurantium tunic may a potential lipid source for immune-regulatory molecules.

Multivariate Analysis Reveals That Unsubstituted β-Ring and C8-Keto Structures Are Important Factors for Anti-Inflammatory Activity of Carotenoids

Carotenoids are natural lipophilic pigments with substantial health benefits. Numerous studies have demonstrated the anti-inflammatory activities of carotenoids, especially toward lipopolysaccharide-induced inflammatory responses. As such, there are few reports on the evaluation and comparison of the anti-inflammatory activities of carotenoids against inflammation induced by other stimuli. In this study, we used pathogen-associated molecular patterns, proinflammatory cytokines, degenerated proteins, and chemical irritants as inflammatory inducers to evaluate the anti-inflammatory activities of eight different carotenoids. Each carotenoid showed characteristic anti-inflammatory activities; thus, we conducted a multivariate analysis to clarify the differences among them. Unsubstituted β-ring (i.e., provitamin A) and C8-keto structures of carotenoids were found to be crucial for their inhibitory effects on the activation of nuclear factor-kappa B and interferon regulatory factors, respectively. Furthermore, we found that β-carotene and echinenone treatment increased intracellular retinoid levels in monocytes and that the retinoids showed the similar activities to β-carotene and echinenone. Taken together, the intake of both provitamin A and C8-keto carotenoids (e.g., siphonaxanthin and fucoxanthin) might be effective in improving the inflammatory status of individuals. A multivariate analysis of anti-inflammatory activities is a useful method for characterizing anti-inflammatory compounds.

Metabolites with Antioxidant Activity from Marine Macroalgae

Reactive oxygen species (ROS) attack biological molecules, such as lipids, proteins, enzymes, DNA, and RNA, causing cellular and tissue damage. Hence, the disturbance of cellular antioxidant homeostasis can lead to oxidative stress and the onset of a plethora of diseases. Macroalgae, growing in stressful conditions under intense exposure to UV radiation, have developed protective mechanisms and have been recognized as an important source of secondary metabolites and macromolecules with antioxidant activity. In parallel, the fact that many algae can be cultivated in coastal areas ensures the provision of sufficient quantities of fine chemicals and biopolymers for commercial utilization, rendering them a viable source of antioxidants. This review focuses on the progress made concerning the discovery of antioxidant compounds derived from marine macroalgae, covering the literature up to December 2020. The present report presents the antioxidant potential and biogenetic origin of 301 macroalgal metabolites, categorized according to their chemical classes, highlighting the mechanisms of antioxidative action when known.

Capsanthin, a Plant-Derived Xanthophyll: a Review of Pharmacology and Delivery Strategies

Capsanthin, a brightly orange-red-coloured pigment responsible for the peculiar red colour of paprika fruits (Capsicum annuum), belongs to xanthophylls, a class of oxygen-containing carotenoids. The characteristic chemical structure of capsanthin containing a keto group in conjunction with a long chain of 11 conjugated dienes is responsible for its strong radical scavenging and singlet oxygen quenching ability. Chemopreventive, antitumour, skin photo-protective, anti-inflammatory, and antidiabetic activities demonstrated by capsanthin are a consequence of its potent antioxidant action. Anti-obesity, anti-adipogenic, and antihyperlipidaemic activities are some of the more important features of capsanthin. With natural origin, bright red colour, and array of health benefits, capsanthin has a potential to be translated into a commercial cosmeceutical, nutraceutical, and/or pharmaceutical. However, the very low aqueous solubility of capsanthin is responsible for its highly variable and poor oral bioavailability. Moreover, its susceptibility to degradation due to heat, light, oxygen, and moisture poses challenges in the development of stable formulations for this otherwise meritorious compound. The current review presents various pharmacological activities of capsanthin and their underlying mechanisms. The review further discusses hitherto explored formulation strategies to improve solubility and stability of capsanthin. Graphical abstract.

The potential of marine resources for retinal diseases: a systematic review of the molecular mechanisms

We rely on vision more than on any other sense to obtain information about our environment. Hence, the loss or even impairment of vision profoundly affects our quality of life. Diet or food components have already demonstrated beneficial effects on the development of retinal diseases. Recently, there has been a growing interest in resources from marine animals and plants for the prevention of retinal diseases through nutrition. Especially fish intake and omega-3 fatty acids have already led to promising results, including associations with a reduced incidence of retinal diseases. However, the underlying molecular mechanisms are insufficiently explained. The aim of this review was to summarize the known mechanistic effects of marine resources on the pathophysiological processes in retinal diseases. We performed a systematic literature review following the PRISMA guidelines and identified 107 studies investigating marine resources in the context of retinal diseases. Of these, 46 studies described the underlying mechanisms including anti-inflammatory, antioxidant, antiangiogenic/vasoprotective, cytoprotective, metabolic, and retinal function effects, which we critically summarize. We further discuss perspectives on the use of marine resources for human nutrition to prevent retinal diseases with a particular focus on regulatory aspects, health claims, safety, and bioavailability.

Unlocking the Health Potential of Microalgae as Sustainable Sources of Bioactive Compounds

Microalgae are known to produce a plethora of compounds derived from the primary and secondary metabolism. Different studies have shown that these compounds may have allelopathic, antimicrobial, and antipredator activities. In addition, in vitro and in vivo screenings have shown that several compounds have interesting bioactivities (such as antioxidant, anti-inflammatory, anticancer, and antimicrobial) for the possible prevention and treatment of human pathologies. Additionally, the enzymatic pathways responsible for the synthesis of these compounds, and the targets and mechanisms of their action have also been investigated for a few species. However, further research is necessary for their full exploitation and possible pharmaceutical and other industrial applications. Here, we review the current knowledge on the chemical characteristics, biological activities, mechanism of action, and the enzymes involved in the synthesis of microalgal metabolites with potential benefits for human health.

Therapeutic attributes and applied aspects of biological macromolecules (polypeptides, fucoxanthin, sterols, fatty acids, polysaccharides, and polyphenols) from diatoms - A review

Diatoms are ubiquitous, biologically widespread, and have global significance due to their unique silica cell wall composition and noteworthy applied aspects. Diatoms are being extensively exploited for environmental monitoring, reconstruction, and stratigraphic correlation. However, considering all the rich elements of diatoms biology, the current literature lacks sufficient information on the therapeutic attributes and applied aspects of biological macromolecules from diatoms, hampering added advances in all aspects of diatom biology. Diatoms offer numerous high-value compounds, such as fatty acids, polysaccharides, polypeptides, pigments, and polyphenols. Diatoms with a high content of PUFA's are targets of transformation into high-value products through microalgal technologies due to their wide application and growing market as nutraceuticals and food supplements. Diatoms are renewable biomaterial, which can be used to develop drug delivery systems due to biocompatibility, surface area, cost-effective ratio, and ease in surface modifications. Innovative approaches are needed to envisage cost-effective ways for the isolation of bioactive compounds, enhance productivity, and elucidate the detailed mechanism of action. This review spotlights the notable applications of diatoms and their biologically active constituents, such as fucoxanthin and omega 3 fatty acids, among others with unique structural and functional entities.

Biological Activities of Paprika Carotenoids, Capsanthin and Capsorubin

Paprika Capsicum annuum L. (Solanaceae) contains various carotenoids such as capsanthin, capsorubin, cryptocapsin cucurbitaxanthin A, β-cryptoxanthin, capsanthin epoxide, zeaxanthin, and β-carotene. Especially, capsanthin and capsorubin are characteristic carotenoid in paprika. They show strong antioxidative effect. Furthermore, these carotenoids show preventive effect of obesity-related diseases. Dietary paprika carotenoids are absorbed in blood, and they are detected in erythrocytes. It contributes to upregulate endurance performance of athletes by reducing oxygen consumption (VO₂) and the heart rate.

Immunomodulatory Activities of Body Wall Fatty Acids Extracted from Halocynthia aurantium on RAW264.7 Cells

Tunicates are known to contain biologically active materials and one species in particular, the sea peach (Halocynthia aurantium), has not been thoroughly studied. In this study we aimed to analyze the fatty acids profile of the H. aurantium body wall and its immunomodulatory effects on RAW264.7 macrophage-like cells. The fatty acids were classified into three categories: saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs). Omega-3 fatty acid content, including EPA and DHA, was higher than omega-6 fatty acids. H. aurantium body wall fatty acids exhibited enhanced immune response and anti-inflammatory effects on RAW264.7 macrophage-like cells. Under normal conditions, fatty acids significantly increase nitric oxide (NO) and PGE₂ production in a dose-dependent manner, thereby improving the immune response. On the other hand, in LPS-treated RAW264.7 cells, fatty acids significantly decreased nitric oxide (NO) and PGE2 production in a dose-dependent manner, thereby enhancing anti-inflammatory effects. Fatty acids transcriptionally control the expression of the immune-associated genes, iNOS, IL-1β, IL-6, COX-2, and TNF-α, via the MAPK and NF-κB signaling cascades in RAW264.7 cells. However, in LPSstimulated RAW264.7 cells, H. aurantium body wall fatty acids significantly inhibited expression of inflammatory cytokine; similarly, production of COX-2 and PGE₂ was inhibited. The results of our present study provide insight into the immune-improving and anti-inflammatory effects of H. aurantium body wall fatty acids on macrophages. In addition, our study demonstrates that H. aurantium body wall is a potential source of immune regulatory components.

Chili Pepper Carotenoids: Nutraceutical Properties and Mechanisms of Action

Chili pepper is a prominent cultivated horticultural crop that is traditionally used for food seasoning and is applied for the treatment and prevention of multiple diseases. Its beneficial health properties are due to its abundance and variety of bioactive components, such as carotenoids, capsaicinoids, and vitamins. In particular, carotenoids have important nutraceutical properties, and several studies have focused on their potential in the prevention and treatment of human diseases. In this article, we reviewed the state of knowledge of general aspects of chili pepper carotenoids (biosynthesis pathway, types and content in Capsicum spp., and the effects of processing on carotenoid content) and recent findings on the effects of carotenoid nutraceuticals, such as antioxidant, cancer preventive, anti-inflammatory, cardiovascular disorder preventive, and anti-obesity effects.

Evaluation of Intestinal Absorption of Dietary Halocynthiaxanthin, a Carotenoid from the Sea Squirt Halocynthia roretzi

Halocynthiaxanthin is an acetylenic carotenoid mainly found in Halocynthia roretzi. To date, several bioactivities of halocynthiaxanthin have been reported, but its mechanism of digestion and absorption in mammals has not been studied yet. In this study, we evaluated the intestinal absorption of halocynthiaxanthin in mice. The halocynthiaxanthin-rich fraction was prepared from the tunicate Halocynthia roretzi. Mice were orally administered the fraction at a dose of 5 mg/kg body weight. The halocynthiaxanthin levels in the plasma, liver, and small intestine, were quantified using HPLC-PDA, 1, 3, 6, and 9 h after ingestion. The halocynthiaxanthin-rich fraction mainly consisted of the all-trans form and a small amount of cis forms. These three isomers were detected in the plasma of mice 3 h after ingestion. Time-course changes after the ingestion of this fraction were found, with cis isomers being more abundant than the all-trans isomer in the mouse plasma and liver. In the small intestine, however, the all-trans isomer was primarily detected. The possibility that cis isomers might be absorbed rapidly from the small intestine cannot be denied, but our results suggest that dietary all-trans-halocynthiaxanthin might be isomerized to the cis isomer after intestinal absorption.

Synthesis of Allene-Containing Apocarotenoids by Cross-Coupling Strategy

The stereocontrolled total synthesis of the allene and carbonyl conjugated apocarotenoids, paracentrone and 19-hexanoyloxyparacentrone 3-acetate, was achieved by sequential cross-coupling reactions using boronic acid ester and iodine- or tin-substituted C5 dienes, which were the building blocks for the elongation of the conjugated polyene systems at both terminals.

Nutraceutical characteristics of the brown seaweed carotenoid fucoxanthin

Fucoxanthin (Fx), a major carotenoid found in brown seaweed, is known to show a unique and wide variety of biological activities. Upon absorption, Fx is metabolized to fucoxanthinol and amarouciaxanthin, and these metabolites mainly accumulate in visceral white adipose tissue (WAT). As seen in other carotenoids, Fx can quench singlet oxygen and scavenge a wide range of free radicals. The antioxidant activity is related to the neuroprotective, photoprotective, and hepatoprotective effects of Fx. Fx is also reported to show anti-cancer activity through the regulation of several biomolecules and signaling pathways that are involved in either cell cycle arrest, apoptosis, or metastasis suppression. Among the biological activities of Fx, anti-obesity is the most well-studied and most promising effect. This effect is primarily based on the upregulation of thermogenesis by uncoupling protein 1 expression and the increase in the metabolic rate induced by mitochondrial activation. In addition, Fx shows anti-diabetic effects by improving insulin resistance and promoting glucose utilization in skeletal muscle.

Carotenoids from Cyanobacteria: A Biotechnological Approach for the Topical Treatment of Psoriasis

In this study, five cyanobacteria strains (Alkalinema aff. pantanalense LEGE15481, Cyanobium gracile LEGE12431, Nodosilinea (Leptolyngbya) antarctica LEGE13457, Cuspidothrix issatschenkoi LEGE03282 and Leptolyngbya-like sp. LEGE13412) from the Blue Biotechnology and Ecotoxicology Culture Collection (LEGE CC) of CIIMAR were explored for their biotechnological potential in the treatment of psoriasis. Different extracts were characterized for their pigment profile by HPLC-PDA. The antioxidant potential of the extracts was assessed against the superoxide anion radical (O₂^•-). Their anti-inflammatory and antiproliferative potential was assessed in vitro using the macrophages RAW 264.7 and the human keratinocytes HaCaT as cell-line models, respectively. Terrestrial and freshwater strains presented the highest carotenoid content (33193-63926 μg/g dry extract), with all-trans-β-carotene, zeaxanthin, echinenone and lutein derivatives being the most abundant carotenoids. Acetone was the most effective solvent for pigment extraction. The acetone extracts presented the lowest IC₅₀ values (0.29-0.38 mg dry extract/mL) regarding O₂^•- scavenging, and revealed anti-inflammatory potential, with N. antarctica LEGE13457, A. pantanalense LEGE15481 and Leptolyngbya-like sp. LEGE13412 reducing the nitric oxide (NO) in RAW 264.7 cell culture medium in about 25% (p < 0.05). With the exception of A. pantanalense LEGE15481, all the extracts significantly reduced keratinocyte proliferation (p < 0.05), demonstrating a selective toxicity among the different cell lines. Overall, Leptolyngbya-like sp. LEGE13412 and N. antarctica LEGE13457 seem promising for further exploitation in the framework of psoriasis, due to their antioxidant, anti-inflammatory and antiproliferative potential.

Astaxanthin anticancer effects are mediated through multiple molecular mechanisms: A systematic review

During the latest decades, the interest on the effectiveness of natural compounds and their impact on human health constantly increased, especially on those demonstrating to be effective on cancer. Molecules coming from nature are currently used in chemotherapy like Taxol, Vincristine or Vinblastine, and several other natural substances have been showed to be active in reducing cancer cell progression and migration. Among them, astaxanthin, a xanthophyll red colored carotenoid, displayed different biological activities including, antinflammatory, antioxidant, proapoptotic, and anticancer effects. It can induce apoptosis through downregulation of antiapoptotic protein (Bcl-2, p-Bad, and survivin) expression and upregulation of proapoptotic ones (Bax/Bad and PARP). Thanks to these mechanisms, it can exert anticancer effects towards colorectal cancer, melanoma, or gastric carcinoma cell lines. Moreover, it possesses antiproliferative activity in many experimental models and enhances the effectiveness of conventional chemotherapic drugs on tumor cells underling its potential future use. This review provides an overview of the current knowledge on the anticancer potential of astaxanthin by modulating several molecular targets. While it has been clearly demonstrated its multitarget activity in the prevention and regression of malignant cells in in vitro or in preclinical investigations, further clinical studies are needed to assess its real potential as anticancer in humans.

Skin Irritation Testing beyond Tissue Viability: Fucoxanthin Effects on Inflammation, Homeostasis, and Metabolism

UV light catalyzes the ozone formation from air pollutants, like nitrogen oxides. Since ozone reacts with cutaneous sebum lipids to peroxides and, thus, promotes inflammation, tumorigenesis, and aging, even broad-spectrum sunscreens cannot properly protect skin. Meanwhile, xanthophylls, like fucoxanthin, proved their antioxidant and cytoprotective functions, but the safety of their topical application in human cell-based models remains unknown. Aiming for a more detailed insight into the cutaneous fucoxanthin toxicity, we assessed the tissue viability according to OECD test guideline no. 439 as well as changes in inflammation (IL-1α, IL-6, IL-8), homeostasis (EGFR, HSPB1) and metabolism (NAT1). First, we proved the suitability of our 24-well-based reconstructed human skin for irritation testing. Next, we dissolved 0.5% fucoxanthin either in alkyl benzoate or in ethanol and applied both solutions onto the tissue surface. None of the solutions decreased RHS viability below 50%. In contrast, fucoxanthin ameliorated the detrimental effects of ethanol and reduced the gene expression of pro-inflammatory interleukins 6 and 8, while increasing NAT1 gene expression. In conclusion, we developed an organ-on-a-chip compatible RHS, being suitable for skin irritation testing beyond tissue viability assessment. Fucoxanthin proved to be non-irritant in RHS and already showed first skin protective effects following topical application.

Antioxidant β-cryptoxanthin enhances porcine oocyte maturation and subsequent embryo development in vitro

Oxidative stress is partly responsible for the poor quality of IVM oocytes. The present study investigated the effects of the antioxidant β-cryptoxanthin on the IVM of porcine oocytes and the in vitro development of the ensuing embryos. Oocytes were matured in IVM medium containing different concentrations of β-cryptoxanthin (0, 0.1, 1, 10 or 100 μM). Treatment with 1 µM β-cryptoxanthin (Group 1B) improved polar body extrusion and the expression of maturation-related genes in cumulus cells and oocytes compared with control. In addition, levels of reactive oxygen species decreased significantly in Group 1B, whereas there were significant increases in glutathione levels and expression of the antioxidant genes superoxide dismutase 1 and peroxiredoxin 5 in this group. After parthenogenetic activation, although the cleavage rate did not differ between the control and 1B groups, the blastocyst formation rate was higher in the latter. Moreover, the total number of cells per blastocyst and relative mRNA levels of pluripotency marker and antioxidant genes were significantly higher in the 1B compared with control group. These results demonstrate that β-cryptoxanthin decreases oxidative stress in porcine oocytes and improves their quality and developmental potential.

In vivo and in vitro evaluation for nutraceutical purposes of capsaicin, capsanthin, lutein and four pepper varieties

The purpose of this study is to determine the nutraceutic potential of different Capsicum sp, capsaicin, capsanthin and lutein and provide data in order to clarify the conflicting results obtained for capsaicin by different authors. To achieve these objectives, in vivo (geno/antigenotoxicity and lifespan assays in the animal model Drosophila) and in vitro (cytotoxicity and DNA-fragmentation assays in HL60 promyelocytic cell line) assays were carried out. Results showed that i) none of the tested substances were genotoxic except green hot pepper and capsaicin at the highest tested concentration (5 mg/mL and 11.5 μM respectively), ii) all tested substances except green hot pepper are antimutagenic against H₂O₂-induced damage, iii) only red sweet pepper significantly extend the lifespan and healthspan of D. melanogaster at 1.25 and 2.5 mg/mL, iv) all pepper varieties induce dose-depended cytotoxic effect in HL60 cells with different IC₅₀, and v) all pepper varieties and capsaicin exerted proapoptotic effect on HL60 cells.

IN CONCLUSION

(i) sweet peppers could be suggested as nutraceutical food, (ii) hot peppers should be moderately consumed, and (iii) supplementary studies are necessary to clarify the synergic effect of the carotenoids and capsaicinoids in the hot pepper food matrix.

Protective Efficacy of the Ingestion of Mandarin Orange Containing β-Cryptoxanthin on Lipopolysaccharide-induced Acute Nephritis

β-cryptoxanthin is a common carotenoid pigment found in fruit, especially in Satsuma mandarins and in persimmons. After ingestion, β-cryptoxanthin is distributed to and accumulates in organs, such as the liver, lung, and kidney. Recent studies have reported that because of its antioxidant defense, β-cryptoxanthin performs several important functions in the preservation of human health and in the prevention of several diseases, including cancer and osteoporosis. The present study aims to determine whether β-cryptoxanthin has a protective effect on renal glomeruli during acute nephritis. To develop our acute nephritis mouse model, we induced kidney inflammation in mice using lipopolysaccharide. To analyze pathological changes in the renal glomeruli of these mice, tissue sections of the kidney were analyzed by hematoxylin-eosin and periodic acid-Schiff staining. In mice with acute nephritis, we observed a thickening of the basal membrane in the renal glomeruli. By ultrastructural analysis, abnormalities in the foot cells were also identified. In the β-cryptoxanthin-ingested mice, these pathological changes were decreased. Migration of urinal proteins occurred in mice with acute nephritis, but this was decreased in β-cryptoxanthin-ingested mice, such that it correlated with the blood concentration of β-cryptoxanthin. Furthermore, in β-cryptoxanthin-ingested mice, both the accumulation and activation of inflammatory cells were decreased in the renal glomeruli. These results suggest that β-cryptoxanthin ingestion may produce great improvement in acute nephritis. These findings provide new insights into β-cryptoxanthin and its protective effect, and provide a new target for pharmacological therapy in human disease.

Reaction of Paprika Carotenoids, Capsanthin and Capsorubin, with Reactive Oxygen Species

The reaction of paprika carotenoids, capsanthin and capsorubin, with reactive oxygen species (ROS), such as superoxide anion radical (·O2(-)), hydroxyl radical (·OH), and singlet oxygen ((1)O2), was analyzed by LC/PDA ESI-MS and ESR spectrometry. Capsanthin formed both the 5,6-epoxide and 5,8-epoxide by reaction with ·O2(-) and ·OH. Furthermore, capsanthin also formed 5,6- and 5,8-endoperoxide on reaction with (1)O2. The same results were obtained in the case of capsanthin diacetate. On the other hand, capsorubin showed higher stability against these ROS. Capsorubin formed 7,8-epoxide on reaction with ·O2(-) and ·OH and 7,8-endoperoxide on reaction with (1)O2.

Appraisals of Bangladeshi Medicinal Plants Used by Folk Medicine Practitioners in the Prevention and Management of Malignant Neoplastic Diseases

Cancer is a group of diseases which is categorized to differentiate into diverse cell types and move around in the body to sites of organogenesis that is key to the process of tumor genesis. All types of cancer fall into the group of malignant neoplastic diseases. In Bangladesh, cancer is now one of the foremost killer diseases and its personal, social, and economic bearing are huge. Plant-derived natural compounds (vincristine, vinblastine, etoposide, paclitaxel, camptothecin, topotecan, and irinotecan) are useful for the treatment of cancer. Since there is no extensive ethnobotanical research study in Bangladesh regarding the traditional uses of medicinal plants against neoplasms, therefore, a randomized ethnopharmacological surveys were carried out in 3 districts of Bangladesh to learn more about the usage of anticancer medicinal plants and their chemical constituents having antineoplastic activity. Comprehensive interviews were conducted to the folk medicine practitioners and medicinal plants as pointed out by them were photographed, collected, deposited, and identified at the Bangladesh National Herbarium. The various plant parts have been used by the healers which included whole plant, leaves, fruits, barks, roots, and seeds. This study evaluated considerable potential for discovery of novel compounds with less side effects in the management and prevention of malignancy in cancer.

Accumulation of Paprika Carotenoids in Human Plasma and Erythrocytes

The accumulation (incorporation) of paprika carotenoid in human plasma and erythrocytes was investigated. A paprika carotenoid supplement (14 mg/day) was ingested for 4 weeks by 5 young healthy volunteers (3 men and 2 women). After 2 weeks of carotenoid ingestion, the carotenoid levels in plasma and erythrocytes increased by 1.2-fold and 2.2-fold, respectively. Characteristic carotenoids found in paprika (capsanthin, cucurbitaxanthin A, and cryptocapsin) were detected in both plasma and erythrocytes. An oxidative metabolite of capsanthin (capsanthone) was also found in both plasma and erythrocytes.

Carotenoids from Marine Microalgae: A Valuable Natural Source for the Prevention of Chronic Diseases

Epidemiological studies have shown a relation between antioxidants and the prevention of several chronic diseases. Microalgae are a potential novel source of bioactive molecules, including a wide range of different carotenoids that can be used as nutraceuticals, food supplements and novel food products. The objective of this review is (i) to update the research that has been carried out on the most known carotenoids produced by marine microalgae, including reporting on their high potentialities to produce other less known important compounds; (ii) to compile the work that has been done in order to establish some relationship between carotenoids and oxidative protection and treatment; (iii) to summarize the association of oxidative stress and the various reactive species including free radicals with several human diseases; and (iv) to provide evidence of the potential of carotenoids from marine microalgae to be used as therapeutics to treat or prevent these oxidative stress-related diseases.

Paprika Pigments Attenuate Obesity-Induced Inflammation in 3T3-L1 Adipocytes

Obesity is related to various diseases, such as diabetes, hyperlipidemia, and hypertension. Adipocytokine, which is released from adipocyte cells, affects insulin resistance and blood lipid level disorders. Further, adipocytokine is related to chronic inflammation in obesity condition adipocyte cells. Paprika pigments (PPs) contain large amounts of capsanthin and capsorubin. These carotenoids affect the liver and improve lipid disorders of the blood. However, how these carotenoids affect adipocyte cells remains unknown. Present study examined the effects of PP on adipocytokine secretion, which is related to improvement of metabolic syndrome. In addition, suppressive effects of PP on chronic inflammation in adipocyte cells were analyzed using 3T3-L1 adipocyte cells and macrophage cell coculture experiments. PP promoted 3T3-L1 adipocyte cells differentiation upregulated adiponectin mRNA expression and secretion. Further, coculture of adipocyte and macrophage cells treated with PP showed suppressed interleukin-6 (IL-6), tumor necrosis factor- α (TNF- α ), monocyte chemotactic protein-1 (MCP-1), and resistin mRNA expression, similarly to treatment with troglitazone, which is a PPAR γ ligand medicine. Conclusion. These results suggest that PP ameliorates chronic inflammation in adipocytes caused by obesity. PP adjusts adipocytokine secretion and might, therefore, affect antimetabolic syndrome diseases.

Monogalactosyldiacylglycerols, potent nitric oxide inhibitors from the marine microalga Tetraselmis chui

Methanolic extracts of some marine and freshwater microalgae were tested for their nitric oxide (NO) inhibitory activity on lipopolysaccharide-induced NO production in RAW264.7 macrophage cells. Among the tested extracts, Tetraselmis chui extract showed the strongest NO inhibitory activity, thus selected for further study. NO inhibitory activity guided isolation led to identification of two monogalactosyldiacylglycerols (MGDGs) (2S)-1-O-(6Z,9Z,12Z,15Z-octadecatetranoyl)-2-O-(4Z,7Z,10Z,13Z-hexadecatetranoyl)-3-O-β-D-galactopyranosylglycerol (1) and (2S)-1-O-(9Z,12Z,15Z-octadecatrinoyl)-2-O-(4Z,7Z,10Z,13Z-hexadecatetranoyl)-3-O-β-D-galactopyranosylglycerol (2) from the MeOH extract of T. chui. The stereo-chemistry of 1 was elucidated by classical degradation method. MGDGs 1 and 2 showed strong NO inhibitory activity compared to N(G)-methyl-L-arginine acetate salt, a well known NO inhibitor used as a positive control. Isolated MGDGs suppressed NO production through down-regulation of inducible NO synthase protein. A structure activity relationship study suggested that the polyunsaturated fatty acids of the MGDGs are responsible for NO inhibition. Moreover, increasing unsaturation on the fatty acid side chains enhanced the NO inhibitory potency of the MGDGs.

Carotenoid intake does not affect immune-stimulated oxidative burst in greenfinches

Carotenoid-based integument colouration is extremely widespread in the animal kingdom. It has been hypothesized that carotenoid colouration is used for communicating the health status of the bearers because carotenoids are efficient immunomodulators or antioxidants. However, the latter argument has been recently debated and the mechanisms by which carotenoids modulate immunity or oxidative balance are poorly known. We performed an experiment on wild-caught captive greenfinches, passerine birds with carotenoid-based plumage colouration, in order to test whether dietary carotenoid supplementation affects immune-stimulated oxidative burst of phagocytes in the whole blood and humoral immune response to a novel antigen, Brucella abortus (BA). Additionally, we tested whether immune stimulation with bacterial lipopolysaccharide (LPS) affects blood carotenoid levels. We thus tested the effects of carotenoids on the oxidative burst of phagocytes under neutral conditions and during in vivo immune challenge. LPS injection depleted plasma carotenoids, indicating involvement of these phytochemicals in the immune response. However, we did not find any evidence that manipulation of carotenoid intake had modulated anti-BA antibody production, LPS-stimulated oxidative burst of phagocytes, or basal levels of circulating reactive oxygen species. This indicates that carotenoid intake does not affect endogenous production of reactive oxygen species by immune cells. This finding is consistent with the view that carotenoids are unlikely to provide a direct link between oxidative stress and colouration. However, it remains to be tested whether the oxidative burst of phagocytes induced in our experiment actually inflicts oxidative damage and whether carotenoids play a role in the attenuation of such potential damages.

Beta-cryptoxanthin, plentiful in Japanese mandarin orange, prevents age-related cognitive dysfunction and oxidative damage in senescence-accelerated mouse brain

Increased oxidative stress is known to accelerate age-related pathologies. Beta-cryptoxanthin (β-CRX, (3R)-β,β-caroten-3-ol) is a potent antioxidant that is highly rich in Satsuma mandarin orange (mandarin), which is the most popular fruit in Japan. We investigated the antioxidative and anti-aging effects of β-CRX and mandarin using senescence-accelerated mice (SAMP10), which were characterized by a short lifespan, high generation of superoxide anions in the brain and poor learning ability with aging. β-CRX (0.5-5.0 µg/ml) or mandarin juice (3.8-38.0%) was added to drinking water of SAMP10 one to 12 months of age. β-CRX was dose-dependently incorporated into the cerebral cortex and the contents were similar to the concentration of β-CRX in the human frontal lobe. These mice also had higher learning ability. The level of DNA oxidative damage was significantly lower in the cerebral cortex of mice that ingested β-CRX and mandarin than control mice. In addition, the mice that ingested β-CRX (>1.5 µg/ml) and mandarin (>11.3%) exhibited a higher survival when 12 month-old, the presenile age of SAMP10, than control mice. These results suggest that β-CRX is incorporated into the brain and has an important antioxidative role and anti-aging effect.

Nitrocapsanthin and nitrofucoxanthin, respective products of capsanthin and fucoxanthin reaction with peroxynitrite

The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN).

Fucoxanthin, a marine carotenoid present in brown seaweeds and diatoms: metabolism and bioactivities relevant to human health

The marine carotenoid fucoxanthin can be found in marine brown seaweeds, the macroalgae, and diatoms, the microalgae, and has remarkable biological properties. Numerous studies have shown that fucoxanthin has considerable potential and promising applications in human health. In this article, we review the current available scientific literature regarding the metabolism, safety, and bioactivities of fucoxanthin, including its antioxidant, anti-inflammatory, anticancer, anti-obese, antidiabetic, antiangiogenic and antimalarial activities, and its protective effects on the liver, blood vessels of the brain, bones, skin, and eyes. Although some studies have shown the bioavailability of fucoxanthin in brown seaweeds to be low in humans, many studies have suggested that a dietary combination of fucoxanthin and edible oil or lipid could increase the absorption rate of fucoxanthin, and thus it might be a promising marine drug.

The allenic carotenoid fucoxanthin, a novel marine nutraceutical from brown seaweeds

Obesity and type 2 diabetes are pathologies with rapidly growing prevalence throughout the world. A few molecular targets offer the most hope for anti-obesity and anti-diabetic therapeutics. One of the keys to success will be the induction of uncoupling protein 1 (UCP1) in abdominal white adipose tissue (WAT) and the regulation of cytokine secretions from both abdominal adipose cells and macrophage cells infiltrated into adipose tissue. Anti-obesity and anti-diabetic effects of fucoxanthin, a characteristic carotenoid found in brown seaweeds, have been reported. Nutrigenomic studies reveal that fucoxanthin induces UCP1 in abdominal WAT mitochondria, leading to the oxidation of fatty acids and heat production in WAT. Fucoxanthin improves insulin resistance and decreases blood glucose levels through the regulation of cytokine secretions from WAT. The key structure of carotenoids for the expression of anti-obesity effect is suggested to be the carotenoid end of the polyene chromophore, which contains an allenic bond and two hydroxyl groups.

Artificial food colorants inhibit superoxide production in differentiated HL-60 cells

We tested synthetic food colorants for their antioxidative potential by the in vitro superoxide generation assay in differentiated HL-60 cells in response to phorbol ester. Among the 12 colorants tested, such fluorescein-type red colorants as rose bengal showed potent inhibitory activity without any cytotoxicity under dark conditions. The intracellular accumulation and superoxide anion scavenging effect of rose bengal were at least partly involved in the inhibitory activity.

"Combination-oriented molecular-targeting prevention" of cancer: a model involving the combination of TRAIL and a DR5 inducer

Malignant tumors carry a high risk of death, and the prevention of malignant tumors is a crucial issue in preventive medicine. To this end, many chemopreventive agents have been tested, but the effects of single agents have been found to be insufficient to justify clinical trials. We have therefore hypothesized that combinations of different chemopreventive agents may synergistically enhance the preventive effect of chemopreventive agents used singly. To provide the treating physician with some guideline by which to choose the most effective agents to be combined, we propose a strategy which we have termed the "combination-oriented molecular-targeting prevention" of cancer. As the molecular target of our model, we focused on tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), which specifically causes apoptosis in malignant tumor cells. Many of these agents were found to up-regulate the expression of death receptor 5, a TRAIL receptor. They were also found to synergistically induce apoptosis in malignant tumor cells when combined with TRAIL. Here, we strongly advocate that the strategy of "combination-oriented molecular-targeting prevention" of cancer will be a practical approach for chemoprevention against human malignant tumors.