Antitumor and immunotropic effects of κ-, λ-carrageenan from red marine algae Chondrus armatus and their low-molecular weight (LMW) degradation products were explored. Effects on human esophageal cancer cell lines KYSE30 and FLO1 viability and ability to induce production of pro-and anti-inflammatory cytokines by human monocytes was assessed. All polysaccharides demonstrated antimetabolic and cytostatic activity towards cancer lines, with high-molecular weight carrageenans possessing higher antimetabolic and lower cytostatic activity than their LMW degradation products. All carrageenans induced monocytes to produce pro-inflammatory cytokines IL1β, IL6, IL18, and TNFα. However, secretion of anti-inflammatory cytokine IL10 was induced only by LMW λ-carrageenan, which exhibited the highest cytokine production inducing efficacy overall. We demonstrate that LMW carrageenan degradation products not only retain biological activity of their precursors, but also increase their efficacy in type-dependent manner, allowing for their future development for pharmacological practice. K E Y W O R D Santitumor activity, carrageenan, Chondrus armatus, immunotropic activity

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Ability of high molecular weight (HMW) κ‐ and λ‐carrageenans of the red marine algae Chondrus armatus and their low molecular weight degradation products (LMWDPs) (0.7–20 and 10–170 kDa respectively) to influence functional properties (motility and phagocytosis) of murine peritoneal macrophages was assessed in this study as an in vitro and a weeklong feeding experiment. We demonstrated that, with an exception of one, all carrageenan samples at 100 μg/ml increased cellular motility and dose‐dependently decreased phagocytic activity; LMWDPs of λ‐carrageenan suppressed motility and had no effect on phagocytosis. Oral administration of all the carrageenan samples at 100 μg/kg/day for 7 days to mice had no effect on their clinical appearance, body weight, weight of their liver, spleen or thymus or development of noticeable changes to their inner organs. All samples induced a shift of the cell composition of the peritoneal cavity towards macrophages. Consumption of LMWDPs of κ‐carrageenan resulted in development of leukopenia, however, no changes to relative WBC count were introduced by either of the samples. All samples decreased murine peritoneal macrophages phagocytic activity, with λ‐samples possessing higher efficacy than their κ‐counterparts; all LMWDPs stimulated peritoneal macrophages motility, with κ‐samples possessing higher efficacy than their λ‐counterparts In conclusion, we have shown that κ‐ and λ‐carrageenans of the C. armatus and their LMWDPs suppress phagocytotic activity of peritoneal macrophages under both in vitro and in vivo conditions. This allows them to be viewed as pharmacologically active substances andpropagates the need for their further investigation as such.

A state of titanium oxide and oxynitride coatings on L316 steel has been studied before and after their contact with model biological fluids. Electrokinetic investigation in 1 mmol potassium chloride showed significant (more than 10 times) fall of magnitude of electrostatic potential of thin (200–300 nm) titanium films at pH changing in the range of 5–9 units during 2 h. Nevertheless, zeta-potential of all samples had negative charge under pH > 6.5. Long-term (5 weeks) contact of samples with simulated body fluid (SBF) promoted steel corrosion and titanium oxide and oxynitride films dissolution. On the other hand, sodium and chloride ions precipitation and sodium chloride crystals formation occurred on the samples. Of positive fact is an absence of calcification of tested artificial surfaces in conditions of long-term being in SBF solution. It is supposed decreasing hazard of fast thrombosis and loss of materials functional properties. According to in vitro experiment conducted, prospective biocompatibility of materials tested before and after their contact with SBF lines up following manner: Ti–O–N (1/3) > Ti–O–N (1/1), TiO2 > Steel. It may be explained by: 1) the corrosion-preventive properties of thin titanium oxide and oxynitride films;2) a store of surface negative charge for Ti–O–N (1/3) film; 3) minor augmentation of mass and thickness of titanium films connected with speed of mineralization processes on the interface of solution/solid body. At the same time, initial (before SBF contact) differences of samples wettability became equal. Modifying effect of model biological fluids on physicochemical characteristics of materials tested (roughness enhancement, a reduction or reversion of surface negative potential, sharp augmentation of surface hydrofilicity) should took into account under titanium oxide and oxynitride films formation and a forecast of their optimal biological properties as the materials for cardiovascular stents.

Objective: Comparative analysis of the antitumor characteristics of different pectins and the dependency of their biological effects on the structural features and the molecular weight.Methods: Cell lines of the murine adenocarcinoma of the mammary gland C127, carcinoma of the cervix HeLa, adenocarcinoma of the colon SW620, adenocarcinoma of the mammary gland HTB-30 and the normal cells of the retina RPE were used to study the antitumor activity of the polysaccharides. The assessment of the antitumor and cytotoxic actions of the pectins was made by testing metabolic activity through MTT-assay and by making intravital fluorescent coloring of the live and dead cells using DNA-connecting color Hoechst and propidium iodide.Results: The samples of the citrus pectins in the selected concentration range had a sufficient antitumor effect on the adenocarcinoma C127 cell line by decreasing metabolic activity and the cell proliferation, and also by providing cilinically important cytotoxic effect.Conclusions: The data got in this study demonstrates that the reaction of the cancer cells on pectins depends on the type of the connection used and also on the sensitivity of the cells to pectins.