Fucan-coated silver nanoparticles synthesized by a green method induce human renal adenocarcinoma cell death

Abstract

Polysaccharides containing sulfated L-fucose are often called fucans. The seaweed Spatoglossum schröederi synthesizes three fucans, among which fucan A is the most abundant. This polymer is not cytotoxic against various normal cell lines and is non-toxic to rats when administered at high doses. In addition, it exhibits low toxicity against tumor cells. With the aim of increasing the toxicity of fucan A, silver nanoparticles containing this polysaccharide were synthesized using a green chemistry method. The mean size of these nanoparticles was 210nm. They exhibited a spherical shape and negative surface charge and were stable for 14 months. When incubated with cells, these nanoparticles did not show any toxic effects against various normal cell lines; however, they decreased the viability of various tumor cells, especially renal adenocarcinoma cells 786-0. Flow cytometry analyses showed that the nanoparticles induced cell death responses of 786-0 cells through necrosis. Assays performed with several renal cell lines (HEK, VERO, MDCK) showed that these nanoparticles only induce death of 786-0 cells. The data obtained herein leads to the conclusion that fucan A nanoparticles are promising agents against renal adenocarcinoma.

<p>Synthesis of Silver Nanoparticle Employing Corn Cob Xylan as a Reducing Agent with Anti-<em>Trypanosoma cruzi</em> Activity</p>

“…However, some authors have verified the amount of silver in the structure of nanoparticles containing other polysaccharides. In studies conducted by Amorim et al 27 and Chen et al, 38 7% and 6.7% of silver were found, respectively, in a fucan-coated nanoparticle composition and in nanoparticles synthesized with fungal exopolysaccharide. These values are lower than those obtained by us in our study using corn cob xylans.…”

“…35,36 Similar to the use of xylan employed in this work, in other studies, the use of polysaccharides with reducing agents to synthesize silver nanoparticles has already been described. 27,28,37 Determination of the Composition of NX…”

“…26 Studies from our research group have shown that the green synthesis of silver nanoparticles with polysaccharides has potentiated the biological activity of both polysaccharides and silver. According to Amorim et al, 27 the cytotoxic activity of sulfated polysaccharides (sPS) of the seaweed Spatoglossum schröederi was potentiated against renal adenocarcinoma cells 786-0. Also, the antitumor, immunomodulatory and antibacterial activities of the sPS of the seaweed Dictyota mertensii had intensified.…”

Antibacterial, Antiproliferative, and Immunomodulatory Activity of Silver Nanoparticles Synthesized with Fucans from the Alga Dictyota mertensii

“…In our case, they showed that the FN remained stable for 16 months. Other nanoparticles synthesized thus far have not been stable for so long, although nanoparticles containing sulfated polysaccharides have been described as particles stable for several months [ 11 , 17 ]. An important feature is to be able to maintain the stability of nanoparticles and their surface charge.…”

“…There are several brown seaweed species of the Dictyotales order on the Brazilian coast, of which Spatoglossum schröederi is one of the most commonly studied. Recently, Amorim et al [ 11 ] showed that AgNPs containing fucan from S. schröederi were more effective cytotoxic agents than the fucan alone, which indicated that the AgNPs could potentiate the fucan’s activities. Other Dictyotales, such as Dictyota mertensii , contain antioxidant, antiproliferative, and immunomodulatory SSPs [ 9 , 12 ].…”