Cyanobacteria produce many biologically active metabolites synthesized via nonribosomal synthetic pathways such as cyclic microcystins (MCs) and linear aeruginosins (Aers). The present study aimed to investigate the effects of different MC variants and the newly isolated aerugenosin Aer-865 on macrophages, which represent one of the key effector cells within the innate immune responses. Specifically, our study included RAW 264.7 macrophage activation associated with production of cytotoxic and cytostatic nitric oxide (NO) as well as pro-inflammatory mediators like tumor necrosis factor α (TNFα) and interleukin 6 (IL-6). From the compounds investigated, commonly occurring MC variants (-RR, -YR) and Aer-865 had no significant effects within the non-cytotoxic concentrations tested, i.e. 0.001-1 μM for MCs and 0.1-50 μM for Aer-865. In contrast to known immunoactive MC-LR, the negligible immunomodulatory potential of tested MC congeners could be related to their differences in structure. The knowledge of MC structure-specific activities contributes to the understanding of complex toxicity of different MC variants and most importantly their mixtures. This study is one of the first study that evaluate the effect of larger set of cyanobacterial peptides on macrophages and compare their immunomodulatory potential.
- MeSH
- bakteriální toxiny chemie toxicita MeSH
- bakteriociny chemie toxicita MeSH
- imunomodulace účinky léků MeSH
- makrofágy účinky léků imunologie MeSH
- mikrocystiny chemie toxicita MeSH
- mořské toxiny chemie toxicita MeSH
- myši MeSH
- RAW 264.7 buňky MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The production of cytotoxic molecules interfering with mammalian cells is extensively reported in cyanobacteria. These compounds may have a use in pharmacological applications; however, their potential toxicity needs to be considered. We performed cytotoxicity tests of crude cyanobacterial extracts in six cell models in order to address the frequency of cyanobacterial cytotoxicity to human cells and the level of specificity to a particular cell line. A set of more than 100 cyanobacterial crude extracts isolated from soil habitats (mainly genera Nostoc and Tolypothrix) was tested by MTT test for in vitro toxicity on the hepatic and non-hepatic human cell lines HepG2 and HeLa, and three cell systems of rodent origin: Yac-1, Sp-2 and Balb/c 3T3 fibroblasts. Furthermore, a subset of the extracts was assessed for cytotoxicity against primary cultures of human hepatocytes as a model for evaluating potential hepatotoxicity. Roughly one third of cyanobacterial extracts caused cytotoxic effects (i.e. viability<75%) on human cell lines. Despite the sensitivity differences, high correlation coefficients among the inhibition values were obtained for particular cell systems. This suggests a prevailing general cytotoxic effect of extracts and their constituents. The non-transformed immortalized fibroblasts (Balb/c 3T3) and hepatic cancer line HepG2 exhibited good correlations with primary cultures of human hepatocytes. The presence of cytotoxic fractions in strongly cytotoxic extracts was confirmed by an activity-guided HPLC fractionation, and it was demonstrated that cyanobacterial cytotoxicity is caused by a mixture of components with similar hydrophobic/hydrophilic properties. The data presented here could be used in further research into in vitro testing based on human models for the toxicological monitoring of complex cyanobacterial samples.
- MeSH
- buněčné linie MeSH
- buňky BALB 3T3 MeSH
- buňky Hep G2 MeSH
- cytotoxiny analýza MeSH
- fibroblasty MeSH
- HeLa buňky MeSH
- inhibiční koncentrace 50 MeSH
- komplexní směsi toxicita MeSH
- lidé MeSH
- myši MeSH
- sinice chemie MeSH
- tetrazoliové soli MeSH
- thiazoly MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Aeruginosin-865 (Aer-865), isolated from terrestrial cyanobacterium Nostoc sp. Lukešová 30/93, is the first aeruginosin-type peptide containing both a fatty acid and a carbohydrate moiety, and is the first aeruginosin to be found in the genus Nostoc. Mass spectrometry, chemical and spectroscopic analysis as well as one- and two-dimensional NMR and chiral HPLC analysis of Marfey derivatives were applied to determine the peptidic sequence: D-Hpla, D-Leu, 5-OH-Choi, Agma, with hexanoic and mannopyranosyl uronic acid moieties linked to Choi. We used an AlphaLISA assay to measure the levels of proinflammatory mediators IL-8 and ICAM-1 in hTNF-α-stimulated HLMVECs. Aer-865 showed significant reduction of both: with EC50 values of (3.5±1.5) μg mL(-1) ((4.0±1.7) μM) and (50.0±13.4) μg mL(-1) ((57.8±15.5) μM), respectively. Confocal laser scanning microscopy revealed that the anti-inflammatory effect of Aer-865 was directly associated with inhibition of NF-κB translocation to the nucleus. Moreover, Aer-865 did not show any cytotoxic effect.
- MeSH
- aktivní transport - buněčné jádro účinky léků MeSH
- antiflogistika nesteroidní chemie izolace a purifikace farmakologie MeSH
- buněčné linie MeSH
- down regulace účinky léků MeSH
- glykopeptidy chemie izolace a purifikace farmakologie MeSH
- interleukin-8 biosyntéza MeSH
- lidé MeSH
- lipopeptidy chemie izolace a purifikace farmakologie MeSH
- mezibuněčná adhezivní molekula-1 biosyntéza MeSH
- molekulární struktura MeSH
- NF-kappa B metabolismus MeSH
- Nostoc chemie růst a vývoj MeSH
- transport proteinů účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH