This study summarizes the response of cyanobacterium Spirulina subsalsa HKAR-19 under simulated light conditions of photosynthetically active radiation (PAR), PAR+UV-A (PA), and PAR+UV-A+UV-B (PAB). Exposure to UV radiation caused a significant (P < 0.05) decrease in chlorophyll a, phycocyanin, and total protein. In contrast, total carotene content increased significantly (P < 0.05) under PA and PAB with increasing irradiation time. The photosynthetic efficiency of photosystem II also decreased significantly in PA and PAB radiation. We have also recorded a decrease in the fluorescence emission intensity of phycocyanin under PA and PAB exposure. The phycocyanin fluorescence shifted towards shorter wavelengths (blue-shift) after 72 h of PA and PAB exposure. Intracellular reactive oxygen species (ROS) levels increased significantly in PA and PAB. Fluorescence microscopic images showed an increase in green fluorescence, indicating ROS generation in UV radiation. We have also quantified ROS generation using green and red fluorescence ratio represented as G/R ratio. A 2-6-fold increase in antioxidative enzymes activity was observed to overcome the damaging effects caused by UV stress as compared to untreated control cultures. The lipid peroxidation was assessed in terms of malondialdehyde content which increases significantly (P < 0.05) as the duration of exposure increases. These results suggest that a combined effect of PAR, UV-A, and UV-B was more deleterious than an individual one.
- MeSH
- antioxidancia * metabolismus MeSH
- chlorofyl a metabolismus MeSH
- chlorofyl * metabolismus MeSH
- fotosyntéza * účinky záření MeSH
- fotosystém II - proteinový komplex metabolismus MeSH
- fykokyanin * metabolismus MeSH
- karotenoidy metabolismus MeSH
- peroxidace lipidů účinky záření MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- Spirulina * účinky záření metabolismus MeSH
- ultrafialové záření * MeSH
- Publikační typ
- časopisecké články MeSH
Non-small cell lung cancer (NSCLC) results in high mortality and has gained increasing attention. C-Phycocyanin (C-PC) has been identified as a potential therapeutic inhibitor for NSCLC, but its underlying mechanism remains obscure. The gene expression of the long noncoding RNA neighbour of BRCAI RNA 2 (NBR2) in NSCLC cells was evaluated by quantitative reverse transcription-PCR. The cell capacity for proliferation and migration was examined by EdU and wound-healing assays. Furthermore, the viability and apoptosis of cells was measured with CCK-8 and annexin V/PI, respectively. Next, the protein level of activation of adenosine monophosphate- activated protein kinase and the rapamycin kinase (mTOR) signalling pathway-associated molecules was evaluated by western blotting. H292 cells were pre-treated with C-PC or transfected with plasmids encoding NBR2 or the shNBR2 plasmid, to over-express or knock down NBR2 expression, respectively. NBR2 expression was robustly down-regulated in NSCLC cell lines compared with a normal cell line (BEAS-2B). NBR2 over-expression inhibited migration and promoted apoptosis of H292 cells. Treatment of H292 cells with C-PC enhanced NBR2 levels in a dose- and time-dependent manner. Downregulation of NBR2 in H292 cells inhibited the activity of C-PC on cell proliferation, viability and clone formation. Further mechanistic investigation showed that the down-regulation of NBR2 abolished the modulatory effects of C-PC on the AMPK/mTOR signalling pathway. In conclusion, C-PC inhibits H292 cell growth by enhancing the NBR2/AMPK signalling pathway.
- MeSH
- adenosinmonofosfát farmakologie terapeutické užití MeSH
- annexin A5 farmakologie terapeutické užití MeSH
- apoptóza MeSH
- fykokyanin metabolismus farmakologie terapeutické užití MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- nádory plic * farmakoterapie genetika metabolismus MeSH
- nemalobuněčný karcinom plic * farmakoterapie genetika metabolismus MeSH
- pohyb buněk MeSH
- proliferace buněk MeSH
- proteinkinasy aktivované AMP genetika metabolismus farmakologie MeSH
- RNA dlouhá nekódující * genetika MeSH
- sinkalid metabolismus farmakologie terapeutické užití MeSH
- sirolimus farmakologie terapeutické užití MeSH
- TOR serin-threoninkinasy metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Spirulina platensis, a water blue-green alga, has been associated with potent biological effects, which might have important relevance in atheroprotection. We investigated whether S. platensis or phycocyanobilin (PCB), its tetrapyrrolic chromophore, can activate atheroprotective heme oxygenase-1 (Hmox1), a key enzyme in the heme catabolic pathway responsible for generation of a potent antioxidant bilirubin, in endothelial cells and in a mouse model of atherosclerosis. In vitro experiments were performed on EA.hy926 endothelial cells exposed to extracts of S. platensis or PCB. In vivo studies were performed on ApoE-deficient mice fed a cholesterol diet and S. platensis. The effect of these treatments on Hmox1, as well as other markers of oxidative stress and endothelial dysfunction, was then investigated. Both S. platensis and PCB markedly upregulated Hmox1 in vitro, and a substantial overexpression of Hmox1 was found in aortic atherosclerotic lesions of ApoE-deficient mice fed S. platensis. In addition, S. platensis treatment led to a significant increase in Hmox1 promoter activity in the spleens of Hmox-luc transgenic mice. Furthermore, both S. platensis and PCB were able to modulate important markers of oxidative stress and endothelial dysfunction, such as eNOS, p22 NADPH oxidase subunit, and/or VCAM-1. Both S. platensis and PCB activate atheroprotective HMOX1 in endothelial cells and S. platensis increased the expression of Hmox1 in aortic atherosclerotic lesions in ApoE-deficient mice, and also in Hmox-luc transgenic mice beyond the lipid lowering effect. Therefore, activation of HMOX1 and the heme catabolic pathway may represent an important mechanism of this food supplement for the reduction of atherosclerotic disease.
- MeSH
- aorta účinky léků enzymologie MeSH
- ateroskleróza farmakoterapie enzymologie prevence a kontrola MeSH
- cévní buněčněadhezivní molekula-1 genetika metabolismus MeSH
- fykobiliny aplikace a dávkování MeSH
- fykokyanin aplikace a dávkování MeSH
- hemoxygenasa-1 genetika metabolismus MeSH
- lidé MeSH
- myši inbrední C57BL MeSH
- myši transgenní MeSH
- myši MeSH
- NADPH-oxidasy genetika metabolismus MeSH
- oxidační stres účinky léků MeSH
- Spirulina chemie MeSH
- upregulace účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In vivo fluorescence methods have been accepted as a quick, simple, and useful tool for quantification of phytoplankton organisms. In this paper, we present a case study in which fluorescence methods were employed for the selective detection of potentially toxic cyanobacteria in raw water at the drinking water treatment plant. The occurrence of cyanobacteria in the drinking water reservoir and in raw water was monitored by phycocyanin fluorescence measurements and by standard methods for phytoplankton quantification (cell counts, chlorophyll a). A special attention was paid to the most critical parts of the season -- spring recruitment of cyanobacteria from sediment to water column and autumn bloom collapse. All methods showed similar patterns within the season. Phycocyanin fluorescence was found to be a simple and sensitive indicator of cyanobacteria in water and can serve as a tool that can provide an early warning about the presence of potentially toxic cyanobacterial metabolites in water.
- MeSH
- biliverdin analogy a deriváty MeSH
- Eukaryota genetika MeSH
- fotosyntéza MeSH
- fykoerythrin biosyntéza MeSH
- fykokyanin biosyntéza MeSH
- proteiny MeSH
- Publikační typ
- přehledy MeSH
