astaxanthine and Helicobacter-Infections

Astaxanthin is a carotenoid widely used in salmonid and crustacean aquaculture to provide the pink color characteristic of that species. This application has been well documented for over two decades and is currently the major market driver for the pigment. Additionally, astaxanthin also plays a key role as an intermediary in reproductive processes. Synthetic astaxanthin dominates the world market but recent interest in natural sources of the pigment has increased substantially. Common sources of natural astaxanthin are the green algae Haematococcus pluvialis, the red yeast, Phaffia rhodozyma, as well as crustacean byproducts. Astaxanthin possesses an unusual antioxidant activity which has caused a surge in the nutraceutical market for the encapsulated product. Also, health benefits such as cardiovascular disease prevention, immune system boosting, bioactivity against Helycobacter pylori, and cataract prevention, have been associated with astaxanthin consumption. Research on the health benefits of astaxanthin is very recent and has mostly been performed in vitro or at the pre-clinical level with humans. This paper reviews the current available evidence regarding astaxanthin chemistry and its potential beneficial effects in humans.

Topics: Animals; Antioxidants; Aquaculture; Cardiovascular Diseases; Crustacea; Dietary Supplements; Eukaryota; Helicobacter Infections; Helicobacter pylori; Humans; Immunity; Molecular Structure; Neoplasms; Xanthophylls; Yeasts

Antioxidants are substances capable of inhibiting oxidation. In chronic diseases, inflammatory response cells produce oxygen free radicals. Oxygen free radicals cause DNA damage, and this may lead to gene modifications that might be carcinogenic. Chronic Helicobacter pylori infection causes the production of DNA-damaging free radicals. In recent years, various groups have studied the effects of antioxidants, especially on H. pylori-associated gastric cancer. In most of the studies, it has been shown that H. pylori infection does affect the level of antioxidants measured in the gastric juice, but there are also controversial results. Recent experimental studies, both in vivo and in vitro, have shown that vitamin C and astaxanthin, a carotenoid, are not only free radical scavengers but also show antimicrobial activity against H. pylori. It has been shown that astaxanthin changes the immune response to H. pylori by shifting the Th1 response towards a Th2 T-cell response. Very few experimental studies support the epidemiologic studies, and further studies are needed to describe the effect and the mechanism of antioxidants in the H. pylori immune response.

Topics: Antioxidants; Ascorbic Acid; beta Carotene; DNA Damage; Helicobacter Infections; Helicobacter pylori; Humans; Risk Factors; Stomach Neoplasms; Th1 Cells; Th2 Cells; Xanthophylls

The aim of this study was to evaluate the efficacy of the natural antioxidant astaxanthin in functional dyspepsia in different doses and compared with placebo.. The study was a controlled, prospective, randomized, and double blind trial.. Patients with functional dyspepsia, divided into three groups with 44 individuals in each group (placebo, 16mg, or 40mg astaxanthin, respectively).. Participants were asked to accept gastroscopy before treatment, together with questionnaires: GSRS and SF-36. Urea breath test (UBT) was done before the treatment.. The primary objective was to test the hypothesis that the antioxidant astaxanthin at two doses regimens compared to placebo should ameliorate gastrointestinal discomfort measured as GSRS in patients with functional dyspepsia, who were either positive or negative for Helicobacter pylori, after 4 weeks of treatment.. At the end of therapy (week 4) no difference between the three treatment groups was observed regarding mean Gastrointestinal Symptom Rating Scale (GSRS) scores of abdominal pain, indigestion and reflux syndromes. The same results were observed at the end of follow-up. However reduction of reflux syndrome before treatment to week 4 was significantly pronounced in the higher (40mg) dose compared to the other treatment groups (16mg and placebo, p=0.04).. In general, no curative effect of astaxanthin was found in functional dyspepsia patients. Significantly greater reduction of reflux symptoms were detected in patients treated with the highest dose of the natural antioxidant astaxanthin. The response was more pronounced in H. pylori-infected patients.

Topics: Adult; Antioxidants; Double-Blind Method; Dyspepsia; Female; Helicobacter Infections; Helicobacter pylori; Humans; Male; Middle Aged; Patient Compliance; Prospective Studies; Quality of Life; Xanthophylls

The chronic active inflammation caused by Helicobacter pylori is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins are involved in the inflammatory process. The aim of this study was to investigate the effect of astaxanthin on gastric inflammation in patients with functional dyspepsia. Forty-four consecutive patients were included, and biopsies were examined for IL-4, IL-6, IL-8, IL-10, interferon-gamma, CD4, CD8, CD14, CD19, CD25 and CD30. Patients were randomized: 21 patients were treated with 40 mg of astaxanthin daily, and 23 patients were treated with a placebo. There was a significant decrease in gastric inflammation in H. pylori-positive patients from both groups. There were no significant changes in the density of H. pylori or in any of the interleukins during or after treatment. There was a significant up-regulation of CD4 and down-regulation of CD8 in patients with H. pylori treated with astaxanthin. Astaxanthin had an effect on the inflammation and on the density of H. pylori in mice in a study where the diet could be standardized without antioxidants (Bennedsen et al., 1999). These dietary conditions are impossible in studies involving humans, and may be due to the minor effect when the host have access to antioxidants in their diet.

Topics: Adult; Aged; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antigens, CD; Biomarkers; Biopsy; Colony Count, Microbial; Cytokines; Disease Models, Animal; Dyspepsia; Female; Helicobacter Infections; Humans; Inflammation; Male; Mice; Middle Aged; Stomach; Xanthophylls

Topics: Adenosine Triphosphate; Antioxidants; Cell Line, Tumor; Epithelial Cells; Gastric Mucosa; Gastritis; Helicobacter Infections; Helicobacter pylori; Host-Pathogen Interactions; Humans; Interleukin-8; Membrane Potential, Mitochondrial; Mitochondria; NF-kappa B; Oxidative Stress; PPAR gamma; Reactive Oxygen Species; Signal Transduction; Xanthophylls

Helicobacter pylori infection in humans is associated with chronic type B gastritis, peptic ulcer disease, and gastric carcinoma. A high intake of carotenoids and vitamin C has been proposed to prevent development of gastric malignancies. The aim of this study was to explore if the microalga Haematococcus pluvialis rich in the carotenoid astaxanthin and vitamin C can inhibit experimental H. pylori infection in a BALB/cA mouse model. Six-week-old BALB/cA mice were infected with the mouse-passaged H. pylori strain 119/95. At 2 weeks postinoculation mice were treated orally once daily for 10 days (i) with different doses of algal meal rich in astaxanthin (0.4, 2, and 4 g/kg of body weight, with the astaxanthin content at 10, 50, and 100 mg/kg, respectively), (ii) with a control meal (algal meal without astaxanthin, 4 g/kg), or (iii) with vitamin C (400 mg/kg). Five mice from each group were sacrificed 1 day after the cessation of treatment, and the other five animals were sacrificed 10 days after the cessation of treatment. Culture of H. pylori and determination of the inflammation score of the gastric mucosae were used to determine the outcome of the treatment. Mice treated with astaxanthin-rich algal meal or vitamin C showed significantly lower colonization levels and lower inflammation scores than those of untreated or control-meal-treated animals at 1 day and 10 days after the cessation of treatment. Lipid peroxidation was significantly decreased in mice treated with the astaxanthin-rich algal meal and vitamin C compared with that of animals not treated or treated with the control meal. Both astaxanthin-rich algal meal and vitamin C showed an inhibitory effect on H. pylori growth in vitro. In conclusion, antioxidants may be a new strategy for treating H. pylori infection in humans.

Topics: Agar; Animals; Ascorbic Acid; beta Carotene; Carotenoids; Disease Models, Animal; Helicobacter Infections; Helicobacter pylori; Lipid Peroxidation; Mice; Mice, Inbred BALB C; Xanthophylls

Helicobacter pylori is a gram-negative bacterium affecting about half of the world population, causing chronic gastritis type B dominated by activated phagocytes. In some patients the disease evolves into gastric ulcer, duodenal ulcer, gastric cancer or MALT lymphoma. The pathogenesis is in part caused by the immunological response. In mouse models and in human disease, the mucosal immune response is characterized by activated phagocytes. Mucosal T-lymphocytes are producing IFN-gamma thus increasing mucosal inflammation and mucosal damage. A low dietary intake of antioxidants such as carotenoids and vitamin C may be an important factor for acquisition of H. pylori by humans. Dietary antioxidants may also affect both acquisition of the infection and the bacterial load of H. pylori infected mice. Antioxidants, including carotenoids, have anti-inflammatory effects. The aim of the present study was to investigate whether dietary antoxidant induced modulation of H. pylori in mice affected the cytokines produced by H. pylori specific T-cells. We found that treatment of H. pylori infected mice with an algal cell extract containing the antioxidant astaxanthin reduces bacterial load and gastric inflammation. These changes are associated with a shift of the T-lymphocyte response from a predominant Th1-response dominated by IFN-gamma to a Th1/Th2-response with IFN-gamma and IL-4. To our knowledge, a switch from a Th1-response to a mixed Th1/Th2-response during an ongoing infection has not been reported previously.

Topics: Animals; Antioxidants; beta Carotene; Cytokines; Gastritis; Helicobacter Infections; Helicobacter pylori; Interferon-gamma; Interleukin-4; Mice; Mice, Inbred BALB C; Spleen; T-Lymphocytes, Helper-Inducer; Xanthophylls