Antioxidant, Immunomodulating, and Microbial-Modulating Activities of the Sustainable and Ecofriendly Spirulina.

The highly nutritional and ecofriendly Spirulina (Arthrospira platensis) has hypolipidemic, hypoglycemic, and antihypertensive properties. Spirulina contains functional compounds, such as phenolics, phycocyanins, and polysaccharides, with antioxidant, anti-inflammatory, and immunostimulating effects. Studies conducted on Spirulina suggest that it is safe in healthy subjects, but attitude to eating probably affects the acceptability of Spirulina containing foods. Although the antioxidant effect of Spirulina is confirmed by the intervention studies, the concerted modulation of antioxidant and inflammatory responses, suggested by in vitro and animal studies, requires more confirmation in humans. Spirulina supplements seem to affect more effectively the innate immunity, promoting the activity of natural killer cells. The effects on cytokines and on lymphocytes' proliferation depend on age, gender, and body weight differences. In this context, ageing and obesity are both associated with chronic low grade inflammation, immune impairment, and intestinal dysbiosis. Microbial-modulating activities have been reported in vitro, suggesting that the association of Spirulina and probiotics could represent a new strategy to improve the growth of beneficial intestinal microbiota. Although Spirulina might represent a functional food with potential beneficial effects on human health, the human interventions used only supplements. Therefore, the effect of food containing Spirulina should be evaluated in the future.

Anaphylaxis to Spirulina confirmed by skin prick test with ingredients of Spirulina tablets.

Spirulina (Arthrospira platensis), blue-green microalgae, has high content in proteins, γ-linoleic acid and vitamins and therefore gained popularity as food supplement. According to the Food and Agriculture Organization of the United Nations Spirulina is also an interesting alternative and sustainable protein source with the growing world population. We present a case of a 17-year-old male, who developed anaphylaxis the first time he ingested a Spirulina tablet. Skin prick test with diluted Spirulina tablet was positive. Further skin prick testing with separated ingredients (Spirulina platensis algae, silicon dioxide, inulin and magnesium stearate) was only positive for Spirulina platensis algae and negative in controls, confirming the allergy was caused by Spirulina and not by one of the additives. This case report shows that diagnosis of Spirulina allergy can safely be made by skin prick test with dilutions of the A. platensis or even more simple by skin prick test with the diluted tablet. Since Spirulina has gained popularity as food and nutritional supplement, it is important to realize the potential risk of this dietary supplement. Before Spirulina is produced and consumed on a wider scale, allergenicity risk assessment should be performed, including investigation of potential crossreactivity with well-known inhalant allergens and foods.

Effect of Spirulina (Arthrospira) supplementation on the immune response to tetanus toxoid vaccination in a mouse model.

The aim of this study was to investigate whether Spirulina (Arthrospira) supplementation could enhance the immune response to tetanus toxoid (TT) vaccine in a mouse model. Vaccination of TT was performed on day 7 and 21 in mice fed daily with Spirulina (50 and 150 mg/kg body weight). Both Spirulina supplementation and TT vaccination did not significantly affect body weight gain of the mice. Supplementation of Spirulina significantly enhanced IgG level (p = .01) after the first but not after the second TT vaccination. The anti-TT IgG levels of the groups that received low dose and high dose of Spirulina were not significantly different. Spirulina supplementation did not show significant effects on in vitro splenocyte proliferation and cytokine (IFN-γ and IL-4) production induced by Con A and TT. This study showed that Spirulina supplementation could enhance primary immune response in terms of antibody production, but not secondary immune response following TT vaccination in a mouse model.

The effects of Spirulina on anemia and immune function in senior citizens.

Anemia and immunological dysfunction (i.e. immunosenescence) are commonly found in older subjects and nutritional approaches are sought to counteract these phenomena. Spirulina is a filamentous and multicellular bule-green alga capable of reducing inflammation and also manifesting antioxidant effects. We hypothesized that Spirulina may ameliorate anemia and immunosenescence in senior citizens with a history of anemia. We enrolled 40 volunteers of both sexes with an age of 50 years or older who had no history of major chronic diseases. Participants took a Spirulina supplementation for 12 weeks and were administered comprehensive dietary questionnaires to determine their nutritional regimen during the study. Complete cell count (CCC) and indoleamine 2,3-dioxygenase (IDO) enzyme activity, as a sign of immune function, were determined at baseline and weeks 6 and 12 of supplementation. Thirty study participants completed the entire study and the data obtained were analyzed. Over the 12-week study period, there was a steady increase in average values of mean corpuscular hemoglobin in subjects of both sexes. In addition, mean corpuscular volume and mean corpuscular hemoglobin concentration also increased in male participants. Older women appeared to benefit more rapidly from Spirulina supplements. Similarly, the majority of subjects manifested increased IDO activity and white blood cell count at 6 and 12 weeks of Spirulina supplementation. Spirulina may ameliorate anemia and immunosenescence in older subjects. We encourage large human studies to determine whether this safe supplement could prove beneficial in randomized clinical trials.

White shrimp Litopenaeus vannamei that had received the hot-water extract of Spirulina platensis showed earlier recovery in immunity and up-regulation of gene expressions after pH stress.

White shrimp Litopenaeus vannamei which had been immersed in seawater (35‰, pH 8.2) containing the hot-water extract of Spirulina platensis at 0 (control), 200, 400, and 600 mg L(-1) for 3 h, were transferred to seawater at pH 6.8, and the immune parameters and transcripts of the lipopolysaccharide- and ß-glucan-binding protein (LGBP), peroxinectin (PX), and integrin ß (IB) were examined 6-96 h post-transfer. Shrimp with no exposure to the hot-water extract and no pH change served as the background control. Results indicated that the hyaline cells, granular cells (including semi-granular cells), total haemocyte count, phenoloxidase activity, respiratory burst, superoxide dismutase activity, glutathione peroxidase activity, and lysozyme activity of shrimp transferred to seawater at pH 6.8 significantly decreased to the lowest at 6 h post-transfer. These immune parameters of shrimp immersed in 600 mg L(-1) of the extract were significantly higher than those of control shrimp at 24-96 h post-transfer, and had returned to the background values earlier at 48-72 h post-transfer with significant transcripts of LGBP, PX, and IB at 24, 6, and 24 h, respectively, whereas these parameters of control shrimp returned to the original values at ≥96 h post-transfer.

Enhancement of antitumor natural killer cell activation by orally administered Spirulina extract in mice.

Oral administration of hot-water extract of Spirulina, cyanobacterium Spirulina platensis, leads to augmentation of NK cytotoxicity in humans. Here, we applied to syngeneic tumor-implant mice (C57BL/6 versus B16 melanoma) Spirulina to elucidate the mechanism of raising antitumor NK activation. A B16D8 subcell line barely expressed MHC class I but about 50% expressed Rae-1, a ligand for NK activation receptor NKG2D. The Rae-1-positive population of implant B16 melanoma was effectively eliminated in the tumor mass progressed in mice. This antitumor activity was induced in parallel with IFN-gamma and abolished in mice by treatment with asialoGM-1 but not CD8beta Ab, suggesting the effector is NK cell. NK cell activation occurred in the spleen of wild-type mice medicated with Spirulina. This Spirulina-mediated enhanced NK activation was abrogated in MyD88 -/- mice but not in TICAM-1 -/- mice. The NK activating properties of Spirulina depending on MyD88 were confirmed with in vitro bone marrow-derived dendritic cells expressing TLR2/4. In D16D8 tumor challenge studies, the antitumor effect of Spirulina was abolished in MyD88 -/- mice. Hence, orally administered Spirulina enhances tumoricidal NK activation through the MyD88 pathway. Spirulina exerted a synergistic antitumor activity with BCG-cell wall skeleton, which is known to activate the MyD88 pathway via TLR2/4 with no NK enhancing activity. Spirulina and BCG-cell wall skeleton synergistically augmented IFN-gamma production and antitumor potential in the B16D8 versus C57BL/6 system. We infer from these results that NK activation by Spirulina has some advantage in combinational use with BCG-cell wall skeleton for developing adjuvant-based antitumor immunotherapy.

[The influence of Spirulina and Selen-Spirulina on some indexes of rat's immune status].

This paper reviews evidence for the immune-enhancing effect of Spirulina (Sp) and Selen-Spirulina (Se-Sp) in male Wistar rats. The rats of control group fed half-synthetic diet. Rats of experimental groups consumed the half-synthetic diets with Sp (10 g/kg diet) or Se-Sp (350 microg Se/kg diet) for 2 weeks. Using rats lymphocytes in vitro after phytohemagglutinin stimulation was demonstrated that lymphocytes from Sp and Se-Sp groups secreted of interleukin-2 and interferon-gamma more control group. Induction of interleukin-4 was comparable with once of control group. We believed that Sp and Se-Sp are more effective in stimulating a Th-1--type response and hence potentiates cell-mediated immunity. The immunostimulatory effect of Sp and Se-Sp was confirmed by morphologic and morphometric investigation of rats spleen, also with by NBT-test of peritoneal macrophages.