Dark Sweet Cherry (Prunus avium) Anthocyanins Suppressed ERK1/2-Akt/mTOR Cell Signaling and Oxidative Stress: Implications for TNBC Growth and Invasion.

This study aimed to assess dark sweet cherry (DSC) total polyphenols (WE) and anthocyanins (ACN) against metastatic breast cancer (BC). The WE and ACN anticancer activity and underlying mechanisms were assessed in vitro using 4T1 BC cells. A pilot study using a BALB/C mouse syngeneic model bearing 4T1 tumors assessed the anti-metastatic potential of ACN in vivo. ACN inhibited cell viability with higher potency than WE and reduced reactive oxygen species (ROS) (IC50 = 58.6 µg cyanidin 3-glucoside equivalent (C3G)/mL or 122 µM). ACN induced p38 stress-related intrinsic apoptosis, leading to caspase-3 cleavage and total PARP decrease. ACN suppressed ERK1/2 and Akt/mTOR signaling pathways, which are abnormally activated in BC and promote motility and invasion. This was consistent with suppression of VCAM-1 mRNA, Scr phosphorylation and 88.6% reduction of cells migrating to wounded area. The pilot in vivo results supported the ACN-mediated suppression of angiogenesis in tumors and lungs. ACN also lowered Cenpf mRNA in lungs, associated with lung metastasis lesions and poor survival. Results demonstrated the dual Akt-ERK inhibitory role of ACN and suppression of their downstream pro-invasive targets. These results encourage a larger scale in vivo study to confirm that ACN may help to fight BC invasion and metastasis.

Dark Sweet Cherry (Prunus avium) Phenolics Enriched in Anthocyanins Induced Apoptosis in MDA-MB-453 Breast Cancer Cells through MAPK-Dependent Signaling and Reduced Invasion via Akt and PLCγ-1 Downregulation.

Dark sweet cherries (DSCs) are rich source of phenolics known to exert anticancer and anti-invasive activities. This study elucidated the molecular mechanisms underlying the activity of DSC phenolics against MDA-MB-453 breast cancer cells In Vitro. Cells were treated with DSC phenolics in whole extract (WE), and fractions enriched in anthocyanins (ACN) and proanthocyanidins (PCN) at concentrations that inhibited cell growth by 50%. Results showed that DSC phenolics suppressed Akt and PLCγ-1 activation, and inhibited cell motility and invasion, but only ACN reached significance. The extrinsic and intrinsic apoptotic pathways were also activated by DSC phenolics via caspase-8 cleavage and increased Bax/Bcl-2 ratio, with ACN exhibiting significant activation and stronger PARP-1 cleavage. Furthermore, sustained activation of mitogen-activated protein kinases (MAPKs) ERK1/2 and p38 was observed wherein ERK1/2 (U0126) and p38 (SB203580) inhibitors confirmed crosstalk ERK1/2-Akt and MAPK intrinsic mitochondrial pathways. In conclusion, DSC phenolics inhibited MDA-MB-453 breast cancer cells by targeting cell signaling pathways that induce apoptosis and suppress cell invasion, with ACN showing enhanced chemopreventive activities.

Performance of concanavalin A-immobilized on polyacrylate beads for the detection of human norovirus and hepatitis A virus in fecal specimens.

Quantitative reverse transcription PCR (qRT-PCR) is a sensitive method for the detection of foodborne viruses in fecal samples. However, the performance of qRT-PCR depends on the efficiency of virus concentration methods. In this study, the effect of Concanavalin A (Con A)-immobilized on polyacrylate beads (Con A-PAB) on the qRT-PCR performance, in terms of sensitivity and specificity to detect foodborne viruses in human fecal specimens was compared with commercial viral RNA extraction kit (VRNA). The detection of foodborne viruses by qRT-PCR was validated by viral genome sequencing. Both Con A-PAB and VRNA methods were equally sensitive and specific for detecting hepatitis A virus in fecal specimens. Even though both methods showed high specificity (100% vs. 100%) for detecting human norovirus (HuNoV), Con A-PAB method exhibited higher sensitivity (100% vs. 42.9%) and accuracy (100% vs. 73.3%) compared to VRNA method. In conclusion, the application of Con A-PAB would improve the performance of qRT-PCR for the detection of HuNoV in fecal samples.

Antitumor potential of dark sweet cherry sweet (Prunus avium) phenolics in suppressing xenograft tumor growth of MDA-MB-453 breast cancer cells.

This study investigated in vivo the antitumor activity of dark sweet cherry (DSC) whole extracted phenolics (WE) and fractions enriched in anthocyanins (ACN) or proanthocyanidins (PCA) in athymic mice xenografted with MDA-MB-453 breast cancer cells. Mice were gavaged with WE, ACN or PCA extracts (150 mg/kg body weight/day) for 36 days. Results showed that tumor growth was suppressed at similar levels by WE, ACN and PCA compared to control group (C) without signs of toxicity or significant changes in mRNA oncogenic biomarkers in tumors or mRNA invasive biomarker in distant organs. Tumor protein analyses showed that WE, ACN and PCA induced at similar levels the stress-regulated ERK1/2 phosphorylation, known to be linked to apoptosis induction. However, ACN showed enhanced antitumor activity through down-regulation of total oncogenic and stress-related Akt, STAT3, p38, JNK and NF-kB proteins. In addition, immunohistochemistry analysis of Ki-67 revealed inhibition of tumor cell proliferation with potency WE ≥ ACN ≥ PCA. Differential quantitative proteomic high-resolution nano-HPLC tandem mass spectrometry analysis of tumors from ACN and C groups revealed the identity of 66 proteins associated with poor breast cancer prognosis that were expressed only in C group (61 proteins) or differentially up-regulated (P<.05) in C group (5 proteins). These findings revealed ACN-targeted proteins associated to tumor growth and invasion and the potential of DSC ACN for breast cancer treatment. Results lead to a follow-up study with highly immunodeficient mice/invasive cell line subtype and advanced tumor development to validate the anti-invasive activity of DSC anthocyanins.

Structural Characterization of Cranberry Arabinoxyloglucan Oligosaccharides.

Cranberry ( Vaccinium macrocarpon) products are widely available in North American food, juice, and dietary supplement markets. The use of cranberry is popular for the prevention of urinary tract infections (UTIs) and other reported health benefits. Preliminary findings by our research group indicate that arabinoxyloglucan oligosaccharides are present in cranberry products and may contribute to the antiadhesion properties of urine produced after cranberry consumption, but relatively little is known regarding the oligosaccharide components of cranberry. This report describes the isolation from two cranberry sources and the complete structure elucidation of two arabinoxyloglucan oligosaccharides through the use of carbohydrate-specific NMR spectroscopic and chemical derivatization methods. These compounds were identified as the heptasaccharide ß-d-glucopyranosyl-(1→4)-[α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranose (1) and the octasaccharide ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranose (2). Selected fractions and the isolated compounds were subjected to antimicrobial, cell viability, and E. coli antiadhesion assays. Results indicated that enriched fractions and purified compounds lacked antimicrobial and cytotoxic effects, supporting the potential use of such compounds for disease prevention without the risk for resistance development. Preliminary antiadhesion results indicated that mixtures of oligosaccharides exhibited greater antiadhesion properties than purified fractions or pure compounds. The potential use of cranberry oligosaccharides for the prevention of UTIs warrants continued investigations of this complex compound series.

Quinoa intake reduces plasma and liver cholesterol, lessens obesity-associated inflammation, and helps to prevent hepatic steatosis in obese db/db mouse.

The purpose of this study was to investigate if quinoa (Chenopodium quinoa Willd.), a good source of nutrients, fibre, and phytochemicals, can modulate risk disease biomarkers on obese-diabetic (db/db) mice. The db/db mice fed quinoa-supplemented (quinoa) or AIN-93G diet (obese) were compared to lean control fed AIN-93G diet. Quinoa intake reduced at significant level plasma total-cholesterol (total-c), LDL-c, and oxidized-LDL to levels similar to lean; lessened protein carbonyls and interleukin (IL)-6. The hepatic steatosis and total-c accumulation in liver were also similar between lean and quinoa and lower than obese. Quinoa fibre and phytochemicals may have contributed to these health benefits. However, quinoa intake increased plasma insulin and did not protect from other pathophysiological manifestations of the db/db research model. More studies are needed with other research models and quinoa doses achievable by human diet to validate the clinical relevance of this study.

Non-anthocyanin phenolics in cherry (Prunus avium L.) modulate IL-6, liver lipids and expression of PPARδ and LXRs in obese diabetic (db/db) mice.

Anthocyanin-rich cherries are known for preventing/decreasing risk factors associated with obesity; however, the specific benefits exerted by cherry non-anthocyanin phenolics are not clear. Obese diabetic (db/db) mice fed a diet supplemented with anthocyanin-depleted cherry powder (cherry) were compared to db/db (obese) or lean counterparts (lean) fed a control isocaloric diet for 12 weeks. The reduced plasma interleukin (IL)-6 and improved liver health may be mediated by cherry fibre and non-anthocyanin phenolics. Benefits for liver health included reduction of lipids and protein carbonyls, and modulation of peroxisome proliferator-activated receptor (PPAR)δ mRNA to resemble levels in lean. Lack of plasma antilipidemic, improvement of antioxidant defenses, and PPARα/γ mRNA modulation in liver suggest cherry anthocyanins specific benefits. This is the first study to elucidate in vivo the potential benefits of cherry non-anthocyanin phenolics for diabetes-induced liver disorders and the importance of choosing processing technologies that preserve anthocyanins and health benefits of whole cherries.

Red raspberry (Rubus idaeus L.) intake decreases oxidative stress in obese diabetic (db/db) mice.

Red raspberry fruit intake was investigated on obese diabetic (db/db) mice for 8weeks. Animals fed isocaloric diets (5.3% freeze-dried raspberry, or control) were assessed for obesity-diabetes-disease risk biomarkers. Results showed that raspberry intake improved antioxidant status and lessened plasma interleukin (IL)-6 (0.3-fold of control, p<0.1); most likely through enhancing glutathione peroxidase (GPx) activity in liver (4.3-fold of control), and in blood (2.1-fold of control). Other disease-risk biomarkers were similar between groups (p>0.05). Plasma levels of total cholesterol (T-CHL), low density lipoprotein-cholesterol (LDL-CHL), and resistin were higher in the raspberry group. Overall, the enhanced detoxifying cell defenses exerted by raspberry intake might be due to its polyphenolics and fibre. This study demonstrates in vivo that raspberry intake, at a dose that can be achieved by human consumption, might protect against diabetes-induced oxidative stress.

Red raspberry decreases heart biomarkers of cardiac remodeling associated with oxidative and inflammatory stress in obese diabetic db/db mice.

Early diagnosis of risks of heart disease can be critical to fight cardiovascular diseases (CVD) associated with obesity and diabetes and for the implementation of nutritional interventions. The objective of this study was to investigate the cardioprotective effects of red raspberry consumption in the obese diabetic (db/db) mice using proteomic analysis as a tool. Hearts harvested from db/db mice fed an isocaloric diet (AIN-93G, control group) or AIN-93G supplemented with freeze-dried raspberry (raspberry group) for eight weeks were analyzed for changes in protein expression. Bioinformatics and pathway analysis of proteomic data detected in >50% samples were scrutinized with Database for Annotation, Visualization and Integrated Discovery (DAVID). Histologic analysis, adipokines and lipid quantification in heart tissues were assessed as end points for disease biomarkers. Results from proteomic data identified five proteins unique to the control group involved in cardiac remodeling and one involved in stress response. Twenty-five proteins expressed in both groups were differentially downregulated in the raspberry group (p < 0.05) within 0.25-0.7-fold of control. Out of these, seven were involved in cardiac remodeling (e.g. natriuretic peptide precursor type A, 0.25-fold of control), and five were involved in stress response (e.g. glutathione S-transferase A4, 0.49-fold of control). However, no significant differences between raspberry and control groups were detected in heart lipid composition, adipokines, and morphology within the study timeframe. In conclusion, raspberry consumption may be effective in decreasing the levels of oxidative and inflammatory stress that promote morphological changes in the heart at an older age, thus preventing or delaying heart diseases.

Consumption of cranberry beverage improved endogenous antioxidant status and protected against bacteria adhesion in healthy humans: a randomized controlled trial.

Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m(2)) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine.

Development of a fluorometric microplate antiadhesion assay using uropathogenic Escherichia coli and human uroepithelial cells.

A fluorometric microplate assay has been developed to determine Escherichia (E.) coli adhesion to uroepithelial cells (UEC). P-fimbriated E. coli were labeled with BacLight Green and preincubated 30 min with human urine or standard. Fluorescent-E. coli were added to UEC in mircoplates at a 400:1 ratio, incubated 1 h, and washed, and the fluorescence intensity was measured. Specific labeling and adherence were confirmed by flow cytometry. A myricetin (1) standard curve (0-30 µg/mL) was developed; the lower limit of detection was 0.1 µg/mL, and half-maximal inhibitory concentration was 0.88 µg/mL (intra- and interassay coefficients of variance were <10% and <15%, respectively). Vaccinium macrocarpon (cranberry) extracts, quercetin (2), and procyanidins B1 (3), B2 (4), and C1 (5) showed similar inhibition. Antiadhesion activity of urine samples from subjects (n = 12) consuming placebo or V. macrocarpon beverage determined using this assay was positively correlated (R(2) = 0.78; p < 0.01) with a radiolabeled-E. coli assay.

Development and validation of a sensitive, high-throughput bioassay for the adhesion of radiolabeled E. coli to uroepithelial cells in vitro.

Vaccinium macrocarpon (cranberry) products have been used to prevent uropathogenic Escherichia (E.) coli adherence to uroepithelial cells (UEC) and may help reduce risk of urinary tract infection. Reported herein are the development and validation of an assay to assess antiadhesion activity of V. macrocarpon extracts and human urine. P-fimbriated E. coli (CFT073) was labeled with ³H-uridine, then co-incubated with HTB-4 UEC at a 400:1 ratio. V. macrocarpon extracts (0-17 mg proanthocyanidins/mL) were added to ³H-labeled E. coli before co-incubating with UEC. The assay yielded a sensitive inhibition curve: the lower limit of detection and half-maximal inhibitory concentration were 0.43 and 1.59 mg proanthocyanidins/mL for V. macrocarpon extract CEP 55; intra- and interassay coefficients of variance were <10% and <15%, respectively. V. macrocarpon extract CEP 3283 showed identical adhesion inhibition. Serial dilutions of urine from human participants who consumed V. macrocarpon beverages showed a linear decrease in antiadhesion activity. Antiadhesion assays conducted with urine from a human intervention study also showed good agreement with results obtained using the hemagglutination assay. Therefore, a sensitive, high-throughput, biologically relevant antiadhesion assay using ³H-E. coli co-incubated with UEC is reported, which can be used for studying the action of V. macrocarpon bioactives.

Astaxanthin stimulates cell-mediated and humoral immune responses in cats.

Astaxanthin is a potent antioxidant carotenoid and may play a role in modulating immune response in cats. Blood was taken from female domestic shorthair cats (8-9 mo old; 3.2 ± 0.04 kg body weight) fed 0, 1, 5 or 10mg astaxanthin daily for 12 wk to assess peripheral blood mononuclear cell (PBMC) proliferation response, leukocyte subpopulations, natural killer (NK) cell cytotoxic activity, and plasma IgG and IgM concentration. Cutaneous delayed-type hypersensitivity (DTH) response against concanavalin A and an attenuated polyvalent vaccine was assessed on wk 8 (prior to vaccination) and 12 (post-vaccination). There was a dose-related increase in plasma astaxanthin concentrations, with maximum concentrations observed on wk 12. Dietary astaxanthin enhanced DTH response to both the specific (vaccine) and nonspecific (concanavalin A) antigens. In addition, cats fed astaxanthin had heightened PBMC proliferation and NK cell cytotoxic activity. The population of CD3(+) total T and CD4(+) T helper cells were also higher in astaxanthin-fed cats; however, no treatment difference was found with the CD8(+) T cytotoxic and MHC II(+) activated lymphocyte cell populations. Dietary astaxanthin increased concentrations of plasma IgG and IgM. Therefore, dietary astaxanthin heightened cell-mediated and humoral immune responses in cats.

Dietary fish oil and flaxseed oil suppress inflammation and immunity in cats.

The modulatory activity of dietary n-3 fatty acids on inflammation and immune response in domestic cats is unknown. Mature female cats (n=14/treatment) were fed control, fish oil or flaxseed oil diets with n-6:n-3 fatty acid ratios of 20:1, 5:1 and 5:1, respectively, for 12 wk. Immune response was assessed on wk 0, 6 and 12, and skin hypersensitivity response on wk 6 and 12. Fish oil increased (P<0.01) eicosapentaenoic and docosahexaenoic acids in plasma and skin, whereas flaxseed oil increased α-linolenic acid. Fish and flaxseed oils decreased (P<0.01) skin inflammatory response to histamine. Cats fed fish but not flaxseed oil had higher (P<0.05) skin leukotriene LTB(5), but not LTB(4). Fish and flaxseed oils lowered B, total T and T(h) subset populations, and leukocyte proliferative response to PWM (P<0.05). In contrast, there was no change in ConA- or PHA-induced lymphocyte proliferation, Tc and MHC II cell populations, DTH response, NK cytotoxicity, IL-2 production, or plasma IgG concentrations. Therefore, fish and flaxseed oil can reduce skin inflammatory responses in cats, however, flaxseed oil appears less immunosuppressive than fish oil.

Dietary astaxanthin enhances immune response in dogs.

No information is available on the possible role of astaxanthin on immune response in domestic canine. Female Beagle dogs (9-10 mo old; 8.2 ± 0.2 kg body weight) were fed 0, 10, 20 or 40 mg astaxanthin daily and blood sampled on wk 0, 6, 12, and 16 for assessing the following: lymphoproliferation, leukocyte subpopulations, natural killer (NK) cell cytotoxicity, and concentrations of blood astaxanthin, IgG, IgM and acute phase proteins. Delayed-type hypersensitivity (DTH) response was assessed on wk 0, 12 and 16. Plasma astaxanthin increased dose-dependently and reached maximum concentrations on wk 6. Dietary astaxanthin enhanced DTH response to vaccine, concanavalin A-induced lymphocyte proliferation (with the 20mg dose at wk 12) and NK cell cytotoxic activity. In addition, dietary astaxanthin increased concentrations of IgG and IgM, and B cell population. Plasma concentrations of C reactive protein were lower in astaxanthin-fed dogs. Therefore, dietary astaxanthin heightened cell-mediated and humoral immune response and reduced DNA damage and inflammation in dogs.

Pigmented potato consumption alters oxidative stress and inflammatory damage in men.

Pigmented potatoes contain high concentrations of antioxidants, including phenolic acids, anthocyanins, and carotenoids. These bioactive compounds have been implicated in the inhibition or prevention of cellular oxidative damage and chronic disease susceptibility. We assessed the effects of pigmented potato consumption on oxidative stress and inflammation biomarkers in adult males. Free-living healthy men (18-40 y; n = 12/group) consumed 150 g of cooked white- (WP), yellow- (YP), or purple-flesh potatoes (PP) once per day for 6 wk in a randomized study. Blood was collected at baseline and wk 6 to analyze total antioxidant capacity (TAC), DNA damage as assessed by plasma 8-hydroxydeoxyguanosine (8-OHdG), protein oxidation, lipid peroxidation, C-reactive protein (CRP), inflammatory cytokines, lymphoproliferation, NK cytotoxicity, and phenotypes. Potatoes were analyzed for TAC, phenolic acids, anthocyanins, and carotenoids. Compared with the WP group, the YP group had higher concentrations of phenolic acids (P < 0.002) and carotenoids (P < 0.001), whereas the PP group had higher concentrations of phenolic acids (P < 0.002) and anthocyanins (P < 0.001). Men who consumed YP and PP tended to have lower (P < 0.08) plasma IL-6 compared with those consuming WP. The PP group tended to have a lower plasma CRP concentration than the WP group (P = 0.07). The 8-OHdG concentration was lower in men who consumed either YP or PP compared with WP. Pigmented potato consumption reduced inflammation and DNA damage in healthy adult males. This offers consumers an improved nutritional choice in potato consumption.

Effect of astaxanthin supplementation on inflammation and cardiac function in BALB/c mice.

Astaxanthin is an antioxidant with immunomodulatory, anti-inflammatory and anticancer properties. This study evaluated the use of dietary astaxanthin to decrease oxidative stress and improve cardiac function, thereby providing a potential cardioprotective supplement. Female BALB/c mice (8 weeks of age) were fed a semi-synthetic diet containing 0, 0.02 or 0.08% astaxanthin for 8 weeks. Cardiac function was assessed by echocardiography bi-weekly, and blood and tissue samples were collected at 8 weeks. Plasma astaxanthin concentrations increased (p<0.05) dose-dependently to 0.5 and 4 mumol/l in the astaxanthin-supplemented mice. Blood glutathione concentrations and lymphocyte mitochondrial membrane potential were not significantly affected by astaxanthin treatment. However, mice fed 0.08% astaxanthin had higher (p<0.05) heart mitochondrial membrane potential and contractility index compared to the control group. These results support the possible use of dietary astaxanthin for cardiac protection.

Effect of dietary astaxanthin at different stages of mammary tumor initiation in BALB/c mice.

The effects of astaxanthin on tumor growth, cardiac function and immune response in mice were studied. Female BALB/c mice were fed a control diet (diet C) for 8 weeks, 0.005% astaxathin for 8 weeks (diet A), or diet C for weeks 1-5 followed by diet A thereafter (diet CA). Mice were injected with a mammary tumor cell line on day 7 and tumor growth was measured daily. Mice fed diet A had extended tumor latency and lower tumor volume (p<0.05). Interestingly, those fed diet CA showed the fastest tumor growth. Astaxanthin feeding elevated plasma astaxanthin concentrations; there was no difference in plasma astaxanthin between mice fed CA and those fed A. Mice fed diet A, but not CA, had a higher (p<0.05) natural killer cell subpopulation and plasma interferon-gamma concentration compared to those fed diet C. Astaxanthin delayed tumor growth and modulated immune response, but only when astaxanthin was given before tumor initiation. This suggests that an adequate blood astaxanthin status is needed to protect against tumor initiation; conversely, astaxanthin supplementation after tumor initiation may be contraindicated.

Astaxanthin uptake in domestic dogs and cats.

BACKGROUND: Research on the uptake and transport of astaxanthin is lacking in most species. We studied the uptake of astaxanthin by plasma, lipoproteins and leukocytes in domestic dogs and cats. METHODS: Mature female Beagle dogs (18 to 19 mo old; 11 to 14 kg BW) were dosed orally with 0, 0.1, 0.5, 2.5, 10 or 40 mg astaxanthin and blood taken at 0, 3, 6, 9, 12, 18 and 24 h post-administration (n = 8/treatment). Similarly, mature domestic short hair cats (12 mo old; 3 to 3.5 kg body weight) were fed a single dose of 0, 0.02, 0.08, 0.4, 2, 5, or 10 mg astaxanthin and blood taken (n = 8/treatment) at the same interval. RESULTS: Both dogs and cats showed similar biokinetic profiles. Maximal astaxanthin concentration in plasma was approximately 0.14 mumol/L in both species, and was observed at 6 h post-dosing. The plasma astaxanthin elimination half-life was 9 to 18 h. Astaxanthin was still detectable by 24 h in both species. In a subsequent study, dogs and cats were fed similar doses of astaxanthin daily for 15 to 16 d and astaxanthin uptake by plasma, lipoproteins, and leukocytes studied. In both species, plasma astaxanthin concentrations generally continued to increase through d 15 or 16 of supplementation. The astaxanthin was mainly associated with high density lipoprotein (HDL). In blood leukocytes, approximately half of the total astaxanthin was found in the mitochondria, with significant amounts also associated with the microsomes and nuclei. CONCLUSION: Dogs and cats absorb astaxanthin from the diet. In the blood, the astaxanthin is mainly associated with HDL, and is taken up by blood leukocytes, where it is distributed to all subcellular organelles. Certain aspects of the biokinetic uptake of astaxanthin in dogs and cats are similar to that in humans.

Astaxanthin decreased oxidative stress and inflammation and enhanced immune response in humans.

BACKGROUND: Astaxanthin modulates immune response, inhibits cancer cell growth, reduces bacterial load and gastric inflammation, and protects against UVA-induced oxidative stress in in vitro and rodent models. Similar clinical studies in humans are unavailable. Our objective is to study the action of dietary astaxanthin in modulating immune response, oxidative status and inflammation in young healthy adult female human subjects. METHODS: Participants (averaged 21.5 yr) received 0, 2, or 8 mg astaxanthin (n = 14/diet) daily for 8 wk in a randomized double-blind, placebo-controlled study. Immune response was assessed on wk 0, 4 and 8, and tuberculin test performed on wk 8. RESULTS: Plasma astaxanthin increased (P < 0.01) dose-dependently after 4 or 8 wk of supplementation. Astaxanthin decreased a DNA damage biomarker after 4 wk but did not affect lipid peroxidation. Plasma C-reactive protein concentration was lower (P < 0.05) on wk 8 in subjects given 2 mg astaxanthin. Dietary astaxanthin stimulated mitogen-induced lymphoproliferation, increased natural killer cell cytotoxic activity, and increased total T and B cell subpopulations, but did not influence populations of Thelper, Tcytotoxic or natural killer cells. A higher percentage of leukocytes expressed the LFA-1 marker in subjects given 2 mg astaxanthin on wk 8. Subjects fed 2 mg astaxanthin had a higher tuberculin response than unsupplemented subjects. There was no difference in TNF and IL-2 concentrations, but plasma IFN-gamma and IL-6 increased on wk 8 in subjects given 8 mg astaxanthin. CONCLUSION: Therefore, dietary astaxanthin decreases a DNA damage biomarker and acute phase protein, and enhances immune response in young healthy females.