Spasmolytic Effects of Aphanizomenon Flos Aquae (AFA) Extract on the Human Colon Contractility.

The blue-green algae Aphanizomenon flos aquae (AFA), rich in beneficial nutrients, exerts various beneficial effects, acting in different organs including the gut. Klamin® is an AFA extract particularly rich in ß-PEA, a trace-amine considered a neuromodulator in the central nervous system. To date, it is not clear if ß-PEA exerts a role in the enteric nervous system. The aims of the present study were to investigate the effects induced by Klamin® on the human distal colon mechanical activity, to analyze the mechanism of action, and to verify a ß-PEA involvement. The organ bath technique, RT-PCR, and immunohistochemistry (IHC) were used. Klamin® reduced, in a concentration-dependent manner, the amplitude of the spontaneous contractions. EPPTB, a trace-amine receptor (TAAR1) antagonist, significantly antagonized the inhibitory effects of both Klamin® and exogenous ß-PEA, suggesting a trace-amine involvement in the Klamin® effects. Accordingly, AphaMax®, an AFA extract containing lesser amount of ß-PEA, failed to modify colon contractility. Moreover, the Klamin® effects were abolished by tetrodotoxin, a neural blocker, but not by L-NAME, a nitric oxide-synthase inhibitor. On the contrary methysergide, a serotonin receptor antagonist, significantly antagonized the Klamin® effects, as well as the contractility reduction induced by 5-HT. The RT-PCR analysis revealed TAAR1 gene expression in the colon and the IHC experiments showed that 5-HT-positive neurons are co-expressed with TAAR1 positive neurons. In conclusion, the results of this study suggest that Klamin® exerts spasmolytic effects in human colon contractility through ß-PEA, that, by activating neural TAAR1, induce serotonin release from serotoninergic neurons of the myenteric plexus.

Selective monoamine oxidase B inhibition by an Aphanizomenon flos-aquae extract and by its constitutive active principles phycocyanin and mycosporine-like amino acids.

Aphanizomenon flos-aquae (AFA) is a fresh water unicellular blue-green alga that has been traditionally used for over 25 years for its health-enhancing properties. Recent studies have shown the ability of a proprietary AFA extract (Klamin(®)) to improve mood, counteract anxiety, and enhance attention and learning. Aim of this study was to test the monoamine oxidase (MAO) inhibition activity of the same AFA extract and of its constituents phycocyanin (AFA-PC) and mycosporine-like aminoacids (AFA-MAAs). All compounds showed a dose-dependent selective inhibition of MAO-B activity as compared to MAO-A. The IC50 values of the AFA extract (concentration 10 mg/ml), AFA-PC and AFA-MAAs were 6.4 µl/ml, 1.33 µM and 1.98 µM, respectively, evidencing a mixed-type of inhibition for the AFA extract (Ki 0.99 µl/ml), a non-competitive inhibition for AFA-PC (Ki 1.06 µM) and a competitive inhibition for AFA-MAAs (Ki 0.585 µM). These results are important to explain the neuromodulating properties of the AFA extract Klamin(®), which is rich in phenylethylamine, a general neuromodulator, that would nevertheless rapidly destroyed by MAO-B enzymes without the inhibitory activity of the synergic active principles AFA-PC and AFA-MAAs. The present investigation thus proposes the extract as potentially relevant in clinical areas such as mood disorders and neurodegenerative diseases.