Uptake and distribution of astaxanthin in several tissues and plasma lipoproteins in male broiler chickens fed a yeast (Phaffia rhodozyma) with a high concentration of astaxanthin

A natural strategy for astaxanthin stabilization and color regulation: Interaction with proteins

The pigment astaxanthin, one of the carotenoids, is regarded as a functional factor with various biological activities, widely applied in feed, nutraceutical, and cosmetic industries. However, its low stability and poor water solubility limit its application. Examples in nature suggest that binding to proteins is a simple and effective method to improve the stability and bioavailability of astaxanthin. Proteins from algae, fish, and crustaceans have all been demonstrated to have astaxanthin-binding capacity. Inspired by nature, artificial astaxanthin-protein systems have been established in foods. Binding to proteins could bring aquatic species various colors, and changes in the conformation of astaxanthin after binding to proteins leads to color changes. The review innovatively summarizes multiple examples of proteins as means of protecting astaxanthin, giving a reference for exploring and analyzing pigment-protein interactions and providing a strategy for carotenoids stabilization and color regulation, which is beneficial to the broader and deeper applications of carotenoids.

Assessing the Potential of Nutraceuticals as Geroprotectors on Muscle Performance and Cognition in Aging Mice

Aging and frailty are associated with a decline in muscle force generation, which is a direct consequence of reduced muscle quantity and quality. Among the leading contributors to aging is the generation of reactive oxygen species, the byproducts of terminal oxidation. Their negative effects can be moderated via antioxidant supplementation. Krill oil and astaxanthin (AX) are nutraceuticals with a variety of health promoting, geroprotective, anti-inflammatory, anti-diabetic and anti-fatigue effects. In this work, we examined the functional effects of these two nutraceutical agents supplemented via pelleted chow in aging mice by examining in vivo and in vitro skeletal muscle function, along with aspects of intracellular and mitochondrial calcium homeostasis, as well as cognition and spatial memory. AX diet regimen limited weight gain compared to the control group; however, this phenomenon was not accompanied by muscle tissue mass decline. On the other hand, both AX and krill oil supplementation increased force production without altering calcium homeostasis during excitation-contraction coupling mechanism or mitochondrial calcium uptake processes. We also provide evidence of improved spatial memory and learning ability in aging mice because of krill oil supplementation. Taken together, our data favors the application of antioxidant nutraceuticals as geroprotectors to improve cognition and healthy aging by virtue of improved skeletal muscle force production.

Dietary supplementation with natural astaxanthin from Haematococcus pluvialis improves antioxidant enzyme activity, free radical scavenging ability, and gene expression of antioxidant enzymes in laying hens

The objective of this study was to evaluate the effects of natural astaxanthin (ASTA) from Haematococcus pluvialis on production performance, egg quality, antioxidant enzyme activity, free radical scavenging ability, and gene expression of antioxidant enzymes in laying hens. Nongda No. 3 laying hens (n = 450) were randomly allocated to 1 of 5 dietary treatments. Each treatment had 6 replicates of 15 hens each. All birds were assigned to a corn-soybean meal-based diet containing 0, 20, 40, 80, or 160 mg/kg ASTA for 4 wk. With increasing dietary ASTA, no significant effects were observed on egg weight, feed consumption, feed efficiency, laying rate, Haugh unit, or eggshell strength. Yolk color darkened linearly with increasing dose of ASTA (P < 0.05). Glutathione peroxidase activity was improved in the kidney with dietary ASTA at levels of 40 mg/kg. Total superoxide dismutase (SOD) was significantly increased in the liver, kidney, and plasma with dietary ASTA supplementation at 40 mg/kg. With increasing dietary ASTA, the scavenging abilities of hydroxyl radicals and superoxide anions were linearly increased (P < 0.05), and the malondialdehyde content decreased linearly (P < 0.05). Compared with the control group, mRNA expression of Cu-Zn SOD (SOD1), Mn SOD (SOD2), and nuclear factor E2-related factor 2 (NRF2) in the liver and kidney was significantly increased in the 40 mg/kg ASTA group (P < 0.05). The level of GPX4 mRNA in the liver and kidney was significantly increased with ASTA supplementation at 40 and 80 mg/kg (P < 0.05). The results demonstrate that dietary ASTA improves free radical scavenging ability and antioxidant enzyme activity, which may be related in part to the upregulated mRNA expression of genes encoding antioxidant enzymes and NRF2.

Assessment of Response to Moderate and High Dose Supplementation of Astaxanthin in Laying Hens

Simple Summary

With the increasing use of carotenoids, especially astaxanthin as a feed additive in the poultry industry, the concern about the health status of the laying hen and efficacy to improve egg quality in the case of overdosing was raised. Thus, we aimed to evaluate the effects of either moderate or high dose dietary supplementation of astaxanthin on eggs and laying hens’ health status. The results revealed that, at moderate dose increment, astaxanthin is well deposited in egg yolk, efficiently improves egg yolk color, and contributes to ameliorate the general health status of laying hens. Besides, the high dose supplementation presented positive effects on the coloration and enrichment of egg yolk and the health status of laying hens with no significant difference with the moderate doses to some extents. We concluded that it would be beneficial to add astaxanthin to laying hens feed at a moderate dose rather than high dose.

Abstract

In this study, we evaluated the impact of moderate and high dose dietary supplementation of astaxanthin on production performance, quality of eggs, and health status of laying hens. The experiment involved 480 laying hens, divided into four groups of eight replicates. The different groups named A1, A2, A3, and A4 were allocated the same diet supplemented with Haematococcus pluvialis powder to provide 0, 21.3, 42.6, and 213.4 mg of astaxanthin per kilogram of feed, respectively. One-way ANOVA and linear and quadratic regression analysis were used to assess the differences between the groups. The results showed that the production performance of laying hens and the physical quality of eggs did not significantly differ between the groups (p > 0.05). Astaxanthin distribution in tissues was typical per bird, whereas the egg yolk coloration and astaxanthin concentration increased with the supplementation dose (p < 0.001). However, there was a decrease in concentration and coloration efficacy of astaxanthin at high dose supplementation (213.4 mg/kg) compared to moderate doses (21.3 and 42.6 mg/kg). Blood biochemical tests showed some discrepancies that were not ascribed to the effect of diets, and the increase in liver weight in the A4 group compared to others was equated with an adaptation of laying hens to the high dose supplementation. Astaxanthin improved superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and diminished malondialdehyde (MDA) content in both liver and serum; meanwhile, the activities of SOD and GSH-Px in serum were similar between the moderate doses and high dose supplementation. Additionally, astaxanthin alleviated interleukin 2, 4, and 6 (IL-2, IL-4, and IL-6, respectively) in serum, showing the best effect in A3 and A4 groups. Besides, immunoglobulin G and M (IgG and IgM), as well as tumor necrosis factor-alpha and beta (TNF-α and TNF-β), were not much affected. It was concluded that although astaxanthin has no obvious adverse effect on the performance and health status of laying hens, it may not be valuable for egg fortification and health status improvement of laying hens at high dose supplementation. The high dose astaxanthin supplementation up to 213.4 mg/kg in the diet might be avoided.

Effects of supplementing natural astaxanthin from Haematococcus pluvialis to laying hens on egg quality during storage at 4°C and 25°C

The objective of this study was to evaluate the effects of different levels of dietary natural astaxanthin (ASTA) (from the microalga Haematococcus pluvialis) and storage at 4°C and 25°C on the quality of eggs from laying hens. Nongda No. 3 laying hens (n = 450) were randomly allocated to 1 of 5 dietary treatments. Each treatment had 6 replicates of 15 hens each. All birds were assigned to a corn-soybean meal-based diet containing 0, 20, 40, 80, or 160 mg/kg natural ASTA for 4 wk. A total of 540 eggs were collected at the end of the 4-week feeding trial. Sixty fresh eggs were collected and measured for egg quality within 24 h after collection. The other 480 eggs were used in a factorial arrangement with 5 dietary ASTA levels, 4 storage times, and 2 storage temperatures. During the 8-week storage period at 4°C and 25°C, egg quality measurements were performed every 2 wk on 12 eggs per treatment. No significant effects (P > 0.05) on yolk index, yolk pH, Haugh units, weight loss, or eggshell strength were observed with increasing concentrations of dietary ASTA. Yolk color darkened linearly with increasing dose of ASTA (P < 0.05). During storage of eggs, yolk index and Haugh units decreased significantly (P < 0.05), whereas yolk pH and weight loss increased (P < 0.05). An interaction was observed between dietary ASTA level and storage time on yolk index, yolk color, and Haugh units (P < 0.05). These results demonstrated that dietary ASTA from H. pluvialis delayed the decrease in yolk index and yolk color during storage at 4°C and 25°C. Therefore, we speculate that there may be a combined effect of dietary ASTA level and storage time on egg internal quality; this information may provide additional options by which to extend the storage time of eggs.

Novel Insights into the Biotechnological Production of Haematococcus pluvialis-Derived Astaxanthin: Advances and Key Challenges to Allow Its Industrial Use as Novel Food Ingredient

Astaxanthin shows many biological activities. It has acquired a high economic potential and its current market is dominated by its synthetic form. However, due to the increase of the health and environmental concerns from consumers, natural forms are now preferred for human consumption. Haematococcus pluvialis is artificially cultured at an industrial scale to produce astaxanthin used as a dietary supplement. However, due to the high cost of its cultivation and its relatively low biomass and pigment productivities, the astaxanthin extracted from this microalga remains expensive and this has probably the consequence of slowing down its economic development in the lower added-value market such as food ingredient. In this review, we first aim to provide an overview of the chemical and biochemical properties of astaxanthin, as well as of its natural sources. We discuss its bioavailability, metabolism, and biological activities. We present a state-of-the-art of the biology and physiology of H. pluvialis, and highlight novel insights into the biotechnological processes which allow optimizing the biomass and astaxanthin productivities. We are trying to identify some lines of research that would improve the industrial sustainability and economic viability of this bio-production and to broaden the commercial potential of astaxanthin produced from H. pluvialis.

Astaxanthin-Shifted Gut Microbiota Is Associated with Inflammation and Metabolic Homeostasis in Mice

BACKGROUND

Astaxanthin is a red lipophilic carotenoid that is often undetectable in human plasma due to the limited supply in typical Western diets. Despite its presence at lower than detectable concentrations, previous clinical feeding studies have reported that astaxanthin exhibits potent antioxidant properties.

OBJECTIVE

We examined astaxanthin accumulation and its effects on gut microbiota, inflammation, and whole-body metabolic homeostasis in wild-type C57BL/6 J (WT) and β-carotene oxygenase 2 (BCO2) knockout (KO) mice.

METHODS

Six-wk-old male and female BCO2 KO and WT mice were provided with either nonpurified AIN93M (e.g., control diet) or the control diet supplemented with 0.04% astaxanthin (wt/wt) ad libitum for 8 wk. Whole-body energy expenditure was measured by indirect calorimetry. Feces were collected from individual mice for short-chain fatty acid assessment. Hepatic astaxanthin concentrations and liver metabolic markers, cecal gut microbiota profiling, inflammation markers in colonic lamina propria, and plasma samples were assessed. Data were analyzed by 3-way ANOVA followed by Tukey's post hoc analysis.

RESULTS

BCO2 KO but not WT mice fed astaxanthin had ∼10-fold more of this compound in liver than controls (P < 0.05). In terms of the microbiota composition, deletion of BCO2 was associated with a significantly increased abundance of Mucispirillum schaedleri in mice regardless of gender. In addition to more liver astaxanthin in male KO compared with WT mice fed astaxanthin, the abundance of gut Akkermansia muciniphila was 385% greater, plasma glucagon-like peptide 1 was 27% greater, plasma glucagon and IL-1β were 53% and 30% lower, respectively, and colon NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome activation was 23% lower (all P < 0.05) in male KO mice than the WT mice.

CONCLUSIONS

Astaxanthin affects the gut microbiota composition in both genders, but the association with reductions in local and systemic inflammation, oxidative stress, and improvement of metabolic homeostasis only occurs in male mice.

Krill Meal Enhances Antioxidant Levels and n-3 Fatty Acid Content of Egg Yolk from Laying Hens Fed a Low-Pigment Diet

This study was conducted to determine effects of krill meal supplementation on production performance, egg quality, antioxidant substances, and fatty acid composition of egg yolk from hens fed a low-pigment diet. A total of 640 laying hens (Lohmann Brown), which were each 25 weeks old, were divided into 4 dietary treatment groups. Each treatment consisted of 8 replications with 20 laying hens per replication. The treatments were corn-soybean meal basal diet (CS), CS with 7.5% cassava meal (low-pigment; LP), and LP with 1.5 or 3% krill meal. All dietary treatments were formulated to be isocaloric (2,750 kcal/kg metabolizable energy) and isonitrogenous (17.5% crude protein). Birds were raised in an evaporative cooling system house for 8 weeks (25-33 weeks of age). Water was provided ad libitum and feed was provided according to breed requirement recommendations. The LP diets supplemented with krill meal had no effect on production performance and egg quality compared to those of the CS group (P>0.05). However, the LP diet caused a significant reduction in yolk color score, and astaxanthin, vitamin A, and vitamin E contents of egg yolk (P<0.05). However, the contents of these nutrients increased as the level of krill meal was increased in the diets (P<0.05). The highest yolk color score, and astaxanthin, vitamin A, and vitamin E contents were observed in laying hens fed 3% krill meal (P<0.05). The LP diet had no effect on n-3 fatty acid content; however, a significant reduction in the content of n-6 fatty acids, especially linoleic acid was observed (P<0.05). Further reduction occurred when higher level of krill was used in the diets (P<0.05). An increase in krill meal level significantly increased docosahexaenoic acid but not linolenic acid content of egg yolk. Krill meal, therefore, could be used to produce docosahexaenoic acid and antioxidant enriched eggs.

Dietary supplemental microalgal astaxanthin modulates molecular profiles of stress, inflammation, and lipid metabolism in broiler chickens and laying hens under high ambient temperatures

This research was to determine effects of supplemental dietary microalgal astaxanthin (AST) on hepatic gene expression and protein production of redox enzymes, heat shock proteins (HSPs), cytokines, and lipid metabolism in broilers (BR) and laying hens (LH) under high ambient temperatures. A total of 240 (day old) Cornish male BR and 50 (19 wk old) White Leghorn Shavers LH were allotted in 5 dietary treatments with 6 and 10 cages/treatment (8 BR or 1 LH/cage), respectively. The birds were fed corn-soybean meal basal diets supplemented with microalgal (Haematococcus pluvialis) AST at 0, 10, 20, 40, and 80 mg/kg diet for 6 wk. Supplemental AST to the BR diet linearly decreased (P < 0.10, R² = 0.18–0.36) hepatic mRNA levels of several redox status-controlling genes, heat shock protein 70 (HSP70), heat shock transcription factor 1 (HSTF1), c-Jun N-terminal kinase 1 (JNK1), tumor necrosis factor-α, and sterol regulatory element-binding protein 1 (SREBP1). The supplementation linearly elevated (P = 0.04, R² = 0.20) diacylglycerol acyltransferase 2 (DGAT2) mRNA level and produced quadratic changes (P < 0.10, R² = 0.15–0.47) in mRNA levels of glutathione S-transferase (GST), serine/threonine kinase (AKT1), P38 mitogen-activated protein kinase (P38MAKP), lipid metabolism–controlling genes, and the protein production of HSP90 and P38MAPK in the liver. Supplementing AST to the LH diets linearly decreased (P < 0.10, R² = 0.18–0.56) mRNA levels of GST, HSF1, JNK1, and interleukin 10; lipogenesis genes; and JNK1 protein production. However, supplemental dietary AST produced quadratic changes (P < 0.10, R² = 0.26–0.72) in mRNA levels of most antioxidant-, stress-responsive, and lipid metabolism–related genes in the liver of LH. In conclusion, supplemental dietary AST affected the hepatic gene expression and protein production related to redox status, heat stress and inflammation, and lipid metabolism in both BR and LH. The impacts varied with the chicken type and demonstrated linear and quadratic regressions with the inclusion levels of AST.

Effects of astaxanthin produced by Phaffia rhodozyma on growth performance, antioxidant activities, and meat quality in Pekin ducks

This study was conducted to determine the effect of astaxanthin (AX) produced by Phaffia rhodozyma (PR) on growth performance, antioxidant activities, relative organ weight, and meat quality in Pekin ducks. A total of 1,440 female one-day-old Pekin ducklings (52.3 ± 0.4 g) were blocked based on body weight (BW), and randomly allotted to 3 treatments with 8 replicates of 60 birds each. The experiment lasted for 6 wk, and dietary treatments included corn-soybean meal-based diet supplemented with 0, 0.15, and 0.3% PR. The supplementation of AX increased (P < 0.05) body weight gain (BWG) linearly and reduced (P < 0.05) feed-to-gain ratio (F/G) linearly during days 22 to 42. BWG and final BW was increased (P < 0.05) linearly by AX supplementation throughout the experiment. The inclusion of AX increased (P < 0.05) superoxide dismutase, glutathione peroxidase, total antioxidative capacity, and interleukin-6 in the serum linearly, as well as decreased (P < 0.05) serum malondialdehyde linearly. The relative weight of abdominal fat was increased (P < 0.05) linearly by AX supplementation. The inclusion of AX decreased (P < 0.05) cook loss linearly, but increased (P < 0.05) pH24h, water holding capacity and redness (a*) linearly. Taken together, the supplementation of AX (3.458 or 6.915 mg/kg diet) from PR improved final BW, BWG during days 22 to 42 and 1 to 42 and reduced F/G during days 22 to 42, as well as caused positive effects on antioxidant function and meat quality.

The Role of the Reactive Oxygen Species Scavenger Agent, Astaxanthin, in the Protection of Cisplatin-Treated Patients Against Hearing Loss

Emerging evidence of significant hearing loss occurring shortly after cisplatin administration in cancer patients has stimulated research into the causes and treatment of this side effect. Although the aetiology of cisplatin-induced hearing loss (CIHL) remains unknown, an increasing body of research suggests that it is associated with excessive generation of intracellular reactive oxygen species (ROS) in the cochlea. Astaxanthin, a xanthophyll carotenoid, has powerful anti-oxidant, anti-inflammatory, and anti-apoptotic properties based on its unique cell membrane function, diverse biological activities, and ability to permeate the blood-brain barrier. In this review, we summarize the role of ROS in CIHL and the effect of astaxanthin on inhibiting ROS production. We focus on investigating the mechanism of action of astaxanthin in suppressing excessive production of ROS.

Varied effects of dietary carotenoid supplementation on oxidative damage in tissues of two waterfowl species

Carotenoids are regarded as a cornerstone of avian vitality and coloration. Currently, the antioxidant potential of dietary carotenoids is debated for birds. Although some studies support a protective role, others report either no effect or pro-oxidant effects. However, the majority of research on this topic has not analyzed the oxidative status of a series of tissues in animals nor considered a range of carotenoid dosages. We investigated the effects of three levels of carotenoid supplementation on plasma, liver, adipose, heart and breast muscle oxidative damage in two congeneric species of waterfowl that exhibit marked differences in carotenoid coloration. After a 6-week depletion period, captive adult northern pintail (Anas acuta) and mallard (A. platyrhynchos) ducks of both sexes were fed either a carotenoid-depleted diet (<3 μg/g xanthophylls, lutein and zeaxanthin), a carotenoid-supplemented diet (50 μg/g) within physiological range, or a carotenoid-rich diet (100 μg/g) within pharmacological range for 22 to 32 weeks. We hypothesized that these dosages of dietary carotenoids would differentially affect oxidative damage between species and sexes and among the tissues examined. We found that dietary xanthophyll supplementation had no significant effect on tissue pro-oxidation in males and females from both species. Moreover, sex or species differences in oxidative stress were only observed in two tissues (plasma and heart). Significant correlations in the levels of oxidative damage were not observed among the tissues examined. In conclusion, the current study does not support a consistent antioxidant role for dietary carotenoids in the tissues of these two waterfowl species. Instead, our results align with the notion that carotenoids play complex, tissue- and species-specific roles in oxidative status in birds.

Effects of astaxanthin supplementation in healthy and obese dogs

Background

Since astaxanthin (ASX) has potent anti-oxidative effects with inhibitory action of lipid peroxidation and singlet oxygen quenching activity, it is widely used as a functional food for keeping good health in human. Obesity is a risk factor for various metabolic disorders. It is characterized by low-grade chronic inflammation based on oxidative stress by excessively produced ROS. From the point of preventive medicine, natural compounds have been proposed as potential therapeutic agents in the prevention of metabolic disorder in companion animals. The purpose of this study is to evaluate the effects of ASX supplementation in healthy and obese dogs.

Materials and methods

Ten healthy beagle dogs and 5 clinically obese dogs were used in this study. The healthy beagle dogs were randomly divided into 2 groups as follows: control and test groups. The test group dogs received ASX supplementation mixed with the food for 6 weeks. Five clinically obese dogs received ASX supplementation for 8 weeks. Metabolites, hormones and enzymes were measured before and after ASX supplementation.

Results

In the healthy dog groups, after 6 weeks, plasma triglyceride (TG) and malondialdehyde concentrations and lactate dehydrogenase (LDH) values significantly decreased in the test group. There was no significant difference in the control group. In clinically obese dogs, plasma TG concentration decreased after 8 weeks of ASX supplementation. Plasma alanine aminotransferase and LDH values clearly decreased in all 5 dogs and 4 dogs out of 5 dogs, respectively.

Conclusion

ASX supplementation (0.3 mg/kg body weight/day) for 6 weeks in healthy dogs and 8 weeks in obese dogs induced the elevation of antioxidant function and of liver function by ameliorating lipid metabolism.

Inhibitory Effect of Astaxanthin on Oxidative Stress-Induced Mitochondrial Dysfunction-A Mini-Review

Oxidative stress is a major contributor to the pathogenesis of various human diseases as well as to the aging process. Mitochondria, as the center of cellular metabolism and major regulators of redox balance, play a critical role in disease development and progression. Mitochondrial dysfunction involving structural and metabolic impairment is prominent in oxidative stress-related diseases. Increased oxidative stress can damage mitochondria, and subsequent mitochondrial dysfunction generates excesses of mitochondrial reactive oxygen species that cause cellular damage. Mitochondrial dysfunction also activates the mitochondrial apoptotic pathway, resulting in cellular death. Astaxanthin, a red-colored xanthophyll carotenoid, exerts an anti-oxidative and anti-inflammatory effect on various cell lines. In this manner astaxanthin maintains mitochondrial integrity under various pathological conditions. In this review, the inhibitory effects of astaxanthin on oxidative stress-induced mitochondrial dysfunction and related disease development are discussed.

Dose-Dependent Enrichments and Improved Redox Status in Tissues of Broiler Chicks under Heat Stress by Dietary Supplemental Microalgal Astaxanthin

Astaxanthin (AST) is a well-known carotenoid with a high antioxidant capacity. This study was designed to evaluate the nutritional and metabolic effects of microalgal AST added to the diets of broiler chicks under heat stress. A total of 240 Cornish male chicks (1 day old) were divided into six cages per treatment (eight chicks per cage) and fed a corn-soybean meal diet supplemented with AST from Haematococcus pluvialis at 0, 10, 20, 40, and 80 mg/kg for 6 weeks. Heat stress was employed during weeks 4-6. The supplementation led to dose-dependent enrichments ( P < 0.05) of AST and total carotenoids in the plasma, the liver, and the breast and thigh muscles. There were similar enhancements ( P < 0.05) of oxygen-radical-absorbance capacities, but there were decreases or mixed responses ( P < 0.05) of glutathione concentrations and glutathione peroxidase activities in the tissues. In conclusion, supplemental dietary microalgal AST was bioavailable to the chicks and enriched in their tissues independent of heat stress, leading to coordinated changes in their endogenous antioxidant defense and meat quality.

Effects of Dietary Supplementation with Astaxanthin on Histamine Induced Lesions in the Gizzard and Proventriculus of Broiler Chicks

Astaxanthin (ASX) is a xanthophyll pigment isolated from crustaceans and salmonids. Owing to its powerful antioxidant activity, ASX has been reported to have the potential to protect against gastric ulcers and a variety of other illnesses. Histamine (His) is a dietary factor that causes gastric erosion and ulceration in young chicks. In this study, we examined whether ASX had protective effects on dietary histamine-induced lesions in the gizzard and proventriculus of broiler chickens. Four experimental treatment groups were planned: basal diet (BD), BD+His, BD+ASX, and BD+ASX+His, with four chicks (5 days old) in each group and three replications (i.e., a total of 12 chicks per group). The BD was supplemented with either 0.4% His or 100 ppm ASX. The birds were fed ad libitum for 3 weeks, and diets contained no antimicrobial compounds. Supplementing the diet with His significantly decreased body weight gain, but increased the weights of the gizzard and proventriculus of the chicks as compared with those of chicks in the BD group (p<0.05). ASX did not affect His-dependent changes in chick body weight or weights of the gizzard and proventriculus. The loss of gastric glands in the proventriculus, which was observed in His-treated chicks, was not prevented by ASX administration. The frequency of proventricular ulceration, however, was lowered by treatment with ASX, without significant differences between the two supplementation levels. In conclusion, our data showed that ASX might be helpful for alleviating structural damage to the digestive system in poultry under certain stressful conditions.

Astaxanthin prevents TGFβ1-induced pro-fibrogenic gene expression by inhibiting Smad3 activation in hepatic stellate cells

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is a subset of non-alcoholic fatty liver disease, the most common chronic liver disease in the U.S. Fibrosis, a common feature of NASH, results from the dysregulation of fibrogenesis in hepatic stellate cells (HSCs). In this study, we investigated whether astaxanthin (ASTX), a xanthophyll carotenoid, can inhibit fibrogenic effects of transforming growth factor β1 (TGFβ1), a key fibrogenic cytokine, in HSCs.

METHODS

Reactive oxygen species (ROS) accumulation was measured in LX-2, an immortalized human HSC cell line. Quantitative realtime PCR, Western blot, immunocytochemical analysis, and in-cell Western blot were performed to determine mRNA and protein of fibrogenic genes, and the activation of Smad3 in TGFβ1-activated LX-2 cells and primary mouse HSCs.

RESULTS

In LX-2 cells, ROS accumulation induced by tert-butyl hydrogen peroxide and TGFβ1 was abolished by ASTX. ASTX significantly decreased TGFβ1-induced α-smooth muscle actin (α-SMA) and procollagen type 1, alpha 1 (Col1A1) mRNA as well as α-SMA protein levels. Knockdown of Smad3 showed the significant role of Smad3 in the expression of α-SMA and Col1A1, but not TGFβ1, in LX-2 cells. ASTX attenuated TGFβ1-induced Smad3 phosphorylation and nuclear translocation with a concomitant inhibition of Smad3, Smad7, TGFβ receptor I (TβRI), and TβRII expression. The inhibitory effect of ASTX on HSC activation was confirmed in primary mouse HSCs as evidenced by decreased mRNA and protein levels of α-SMA during activation.

CONCLUSION

Taken together, ASTX exerted anti-fibrogenic effects by blocking TGFβ1-signaling, consequently inhibiting the activation of Smad3 pathway in HSCs.

GENERAL SIGNIFICANCE

This study suggests that ASTX may be used as a preventive/therapeutic agent to prevent hepatic fibrosis.

Effect of dietary astaxanthin rich yeast, Phaffia rhodozyma, on meat quality of broiler chickens

We evaluated effects of dietary supplementation with astaxanthin (Ax)-rich yeast, Phaffia rhodozyma (Xanthophyllomyces dendrorhous), on broiler chicken meat quality. Fourteen-day-old female Ross broilers were divided into three groups: control group, Ax-free diet; Ax 10 group, 10 mg/kg Ax diet; and Ax 20 group, 20 mg/kg Ax diet for 28 days. At 42 days old, chickens were slaughtered, and then growth performance, meat quality and sensory attributes were analyzed. Compared with the control, a* values increased significantly after slaughter and 48 h postmortem for Ax 20 samples (P<0.05) and for b* values in Ax 20 and Ax 10 groups (P<0.05). Cooking loss decreased in the Ax 20 group (P<0.05). After 120 h aging, contents of several free amino acids and total free amino acid content of Ax 20 group were significantly higher than the control (P<0.05). In sensory evaluation, meat texture attributes improved significantly in the Ax 20 group (P<0.01). No significant changes occurred in flavor attribute scores of meat soup from the Ax 20 group compared with the control even though most assessors preferred meat soup from the Ax 20 group. Overall, Ax-rich yeast in the diet improves broiler chicken meat quality.

Astaxanthin supplementation does not augment fat use or improve endurance performance

INTRODUCTION

Astaxanthin is a lipid-soluble carotenoid found in a variety of aquatic organisms. Prolonged astaxanthin supplementation has been reported to increase fat oxidative capacity and improve running time to exhaustion in mice. These data suggest that astaxanthin may be applied as a potent ergogenic aid in humans.

PURPOSE

To assess the effect of 4 wk of astaxanthin supplementation on substrate use and subsequent time trial performance in well-trained cyclists.

METHODS

Using a double-blind parallel design, 32 young, well-trained male cyclists or triathletes (age = 25 ± 1 yr, weight = 73 ± 1 kg, V˙O2peak = 60 ± 1 mL·kg·min, Wmax = 395 ± 7 W; mean ± SEM) were supplemented for 4 wk with 20 mg of astaxanthin per day (ASTA) or a placebo (PLA). Before and after the supplementation period, subjects performed 60 min of exercise (50% Wmax), followed by an time trial of approximately 1 h.

RESULTS

Daily astaxanthin supplementation significantly increased basal plasma astaxanthin concentrations from nondetectable values to 187 ± 19 μg·kg (P < 0.05). This elevation was not reflected in greater total plasma antioxidant capacity (P = 0.90) or attenuated malondialdehyde levels (P = 0.63). Whole-body fat oxidation rates during submaximal exercise did not differ between groups and did not change over time (from 0.71 ± 0.04 to 0.68 ± 0.03 g·min and from 0.66 ± 0.04 to 0.61 ± 0.05 g·min in the PLA and ASTA groups, respectively; P = 0.73). No improvements in time trial performance were observed in either group (from 236 ± 9 to 239 ± 7 and from 238 ± 6 to 244 ± 6 W in the PLA and ASTA groups, respectively; P = 0.63).

CONCLUSION

Prolonged astaxanthin supplementation does not augment antioxidant capacity, increase fat oxidative capacity, or improve time trial performance in trained cyclists.

Effects of astaxanthin and esterified glucomannan on hematological and serum parameters, and liver pathological changes in broilers fed aflatoxin-B1-contaminated feed

The effects of astaxanthin (ASTA) and esterified glucomannan (EMG) on hematological and serum parameters, and liver pathological changes in broilers fed on aflatoxin-B1 (AFB1) contaminated diet were investigated. Two hundred and forty 10-day-old broilers were randomly assigned to one of five dietary treatments including: (i) control diet; (ii) AFB1-contaminated diet; (iii) AFB1 + EGM diet; (iv) AFB1 + ASTA diet; and (v) AFB1 + EGM + ASTA diet. At 35 days old, blood and liver tissue samples were collected for analysis. Results indicated that total white blood cell (WBC) number, hemoglobin (Hgb) concentration, hematocrit (Hct) level, serum alanine amino transferase (AST) and γ-glutamyl transferase (GGT) activities, red blood cell (RBC) number, serum globulin (GLB) and urea nitrogen (BUN) concentrations (P < 0.05) were increased by feeding AFB1-contaminated diet. EMG and ASTA alleviated the alteration of RBC, WBC, Hgb and AST caused by AFB1-contaminated diet. Liver superoxide dismutase (SOD) activity was reduced, while myeloperoxidase (MPO) activity was increased by AFB1-contaminated diet (P < 0.05). Both EGM and ASTA restrained the increase of MPO activity (P < 0.05). Degeneration of the liver tissues was found in broilers fed AFB1-contaminated diet. It suggested that feeding 0.4 mg/kg AFB1-contaminated diet resulted in adverse effects on blood parameters and liver morphology. Dietary addition of EGM addition at 5 g/kg diet, ASTA at 10 mg/kg diet and especially their combination showed positive protection effects on alleviating the alteration of feeding AFB1. The results indicated that supplementation of 5 g EGM/kg diet, 10 mg ASTA/kg diet and their combination could partially or greatly alleviate the adverse effects caused by AFB1, with the EGM+ASTA group receiving the most effective treatment.

Astaxanthin ameliorates heat stress-induced impairment of blastocyst development in vitro:--astaxanthin colocalization with and action on mitochondria--

PURPOSE

The effects of astaxanthin (Ax) on the in vitro development of bovine embryos cultured under heat stress were investigated in combination with the assessment of its cellular accumulation and action on mitochondrial membrane potential (ΔΨm).

METHODS

Bovine ≥8-cell embryos were collected on day 3 after in vitro fertilization and exposed to single (day 4) or repeated (day 4 and 5) heat stress (10 h/day at 40.5 °C). Ax was added into culture medium under the repeated heat stress and blastocyst development was evaluated. The cellular uptake of Ax in embryos was examined using bright-field and confocal laser-scanning microscopy, and high-performance liquid chromatography. The relationship between Ax and mitochondria localization was assessed using MitoTracker dye. The effects of Ax on ΔΨm were investigated using JC-1 dye.

RESULTS

Blastocyst development in the repeated heat stress treatment decreased significantly (P < 0.05) compared with those in single heat stress or normal thermal treatment. The addition of Ax into culture medium did lead to a significant recovery in blastocyst development in the repeated heat-treated group. Ax was detected in cytoplasm of embryos and observed to colocalize with mitochondria. Ax recovered ΔΨm in embryos that was decreased by the heat treatment.

CONCLUSIONS

Ax ameliorated the heat stress-induced impairment of blastocyst development. Our results suggest that the direct action of Ax on mitochondrial activity via cellular uptake is a mechanism of the ameliorating effects.

Astaxanthin protects mesangial cells from hyperglycemia-induced oxidative signaling

Astaxanthin (ASX) is a carotenoid that has potent protective effects on diabetic nephropathy in mice model of type 2 diabetes. In this study, we investigated the protective mechanism of ASX on the progression of diabetic nephropathy using an in vitro model of hyperglycemia, focusing on mesangial cells. Normal human mesangial cells (NHMCs) were cultured in the medium containing normal (5 mM) or high (25 mM) concentrations of D-glucose. Reactive oxygen species (ROS) production, the activation of nuclear transcription factors such as nuclear factor kappa B (NFkappaB) and activator protein-1 (AP-1), and the expression/production of transforming growth factor-beta 1 (TGFbeta(1)) and monocyte chemoattractant protein-1 (MCP-1) were evaluated in the presence or absence of ASX. High glucose (HG) exposure induced significant ROS production in mitochondria of NHMCs, which resulted in the activation of transcription factors, and subsequent expression/production of cytokines that plays an important role in the mesangial expansion, an important event in the pathogenesis of diabetic nephropathy. ASX significantly suppressed HG-induced ROS production, the activation of transcription factors, and cytokine expression/production by NHMCs. In addition, ASX accumulated in the mitochondria of NHMCs and reduced the production of ROS-modified proteins in mitochondria. ASX may prevent the progression of diabetic nephropathy mainly through ROS scavenging effect in mitochondria of mesangial cells and thus is expected to be very useful for the prevention of diabetic nephropathy.

Enantioselective separation of all-E-astaxanthin and its determination in microbial sources

A method for the enantioselective separation of all-E-astaxanthin (3,3'-dihydroxy-beta,beta-carotene-4,4'-dione), an important colorant in the feed industry, was developed. Different chiral stationary phases (CSPs) such as Pirkle phases (R,R Ulmo and l-leucine), modified polysaccharides and a beta-cyclodextrin have been investigated on their separation performance of astaxanthin enantiomers. Direct resolution was only achieved employing the Chiralcel OD-RH (cellulose-tris-3,5-dimethylphenyl-carbamate) under reversed phase conditions. The chiral separation of the enantiomeric forms of astaxanthin produced in microalgae and yeasts was reported. The yeast Xanthophyllomyces sp. produces astaxanthin predominantly in the R,R configuration, whereas in the green microalgae Scenedesmus sp. astaxanthin is built primarily in the S,S form. The separation method for the identification of astaxanthin enantiomers is of great interest since astaxanthin is used as functional food additive in human nutrition. Moreover the method may be used as a food chain indicator in farmed salmon.

Effect of dietary supplementation of astaxanthin byPhaffia rhodozymaon lipid peroxidation, drug metabolism and some immunological variables in male broiler chicks fed on diets with or without oxidised fat

1. Effects of dietary supplementation of astaxanthin (Ax) provided from Phaffia rhodozyma on lipid peroxidation, hepatic drug metabolism, antibody titres to sheep red blood cells (SRBC) and splenocyte proliferation to mitogens were determined in male broiler chicks. 2. Chicks, one week old, were given diets with or without oxidised fat (0 or 3.7 meq of peroxide value (POV)/kg diet) and/or Ax (0 or 100 mg/kg diet) for 14 d, ad libitum. 3. Lipid peroxidation, estimated by 2-thiobarbituric acid reactants values in liver, spleen, heart, plasma and hepatic microsomes, were increased by feeding a diet containing oxidised fat (P<0.05) but were not affected by Ax feeding. 4. Cytochrome P-450 contents in hepatic microsome tended to be increased by feeding Ax. 5. Anti-SRBC titre was not affected by oxidised fat or Ax feeding, while plasma immunogloblin (Ig) G concentration was increased by Ax feeding but was not affected by oxidised fat feeding. 6. When chicks were fed on the diet without oxidised fat, Ax enhanced splenocyte proliferation stimulated by both concanavalin A and pokeweed mitogen, while in chicks fed on a diet containing oxidised fat, Ax reduced the proliferation (P<0.01 for Ax and oxidised fat interaction). 7. The results indicated that dietary supplementation of Ax from Phaffia rhodozyma had an impact on T cell proliferation and Ig G production as a part of acquired immunity, but was not effective in preventing lipid peroxidation in male broiler chicks.

Astaxanthin, a carotenoid with potential in human health and nutrition

Astaxanthin (1), a red-orange carotenoid pigment, is a powerful biological antioxidant that occurs naturally in a wide variety of living organisms. The potent antioxidant property of 1 has been implicated in its various biological activities demonstrated in both experimental animals and clinical studies. Compound 1 has considerable potential and promising applications in human health and nutrition. In this review, the recent scientific literature (from 2002 to 2005) is covered on the most significant activities of 1, including its antioxidative and anti-inflammatory properties, its effects on cancer, diabetes, the immune system, and ocular health, and other related aspects. We also discuss the green microalga Haematococcus pluvialis, the richest source of natural 1, and its utilization in the promotion of human health, including the antihypertensive and neuroprotective potentials of 1, emphasizing our experimental data on the effects of dietary astaxanthin on blood pressure, stroke, and vascular dementia in animal models, is described.

Dietary modulation of lens zeaxanthin in quail

Although higher dietary intake of lutein/zeaxanthin has been associated with reduced risk for cataracts, the impact of dietary supplements on lens lutein (L) or zeaxanthin (Z) has not been examined. If higher lens carotenoids do reduce risk for cataract, it would be essential to know whether dietary carotenoids can elevate carotenoids in the adult vertebrate lens. In this study, a covey of Japanese quail were hatched and raised 6 months on carotenoid-deficient diet, then switched to deficient diet supplemented with low or high 3R,3R'-zeaxanthin (5 or 35 mgkg(-1) food) or beta-carotene (50 mgkg(-1) food). Controls included a group of covey-mates that remained on the deficient diet and another raised from birth on the high Z (35 mg Zkg(-1)) diet. At 1 year of age, carotenoids and tocopherols in the lens and in the serum were analysed by HPLC, and compared by analysis of variance. Serum Z was significantly elevated in deficient birds fed the lower or higher Z supplement for 6 months (P<0.0001 for each). Serum Z in birds maintained on the higher Z supplement for 1 year was much higher than that in deficient birds (P<0.0001), but not different from deficient birds given the higher Z supplement. As in humans, the predominant lens carotenoids were lutein (L) and zeaxanthin (Z), and the total carotenoid concentration was of lower magnitude than the concentration of alpha-tocopherol. Responses to Z supplementation were sex-related. Female quail had 5-10 times higher serum concentrations of both Z and L than males (P<0.0001, <0.001), and they also had higher lens Z concentrations than males (P<0.0006); possible effects of estrogen on lens carotenoids are discussed. Lens Z concentration was strongly and positively correlated with serum Z in females (r=0.77; P<0.002). Deficient adult females supplemented with the 35 mgkg(-1) dose of Z for 6 months had a mean lens Z concentration (0.252+/-0.06 microgg(-1) protein) close to that in females fed with the supplement from birth (0.282+/-0.15 microgg(-1) protein). Birds fed with the higher dietary Z supplement for 6 or 12 months had significantly higher lens Z than birds fed lower or no dietary Z (P<0.0001). Lens L was not altered by dietary supplementation with either Z or beta-carotene. beta-Carotene supplements did not result in detectable lens beta-carotene, and had no effect on lens Z. Neither Z nor beta-carotene supplementation had a significant effect on serum or lens tocopherol concentrations. These studies in quail provide the first experimental evidence that lens carotenoids in adult vertebrates can be manipulated by dietary Z supplements.