PROPIONIC ACID SECRETED BY PROPIONIBACTERIUM ACNES MAY MODIFY THE CELLULAR PROPERTIES OF KERATINOCYTES

Propionibacterium acnes (P. acnes) bacterium is a member of the skin microflora, but may also serve as an opportunistic pathogen contributing to the pathogenesis of acne vulgaris. Earlier we have shown that various P. acnes strains (889, 6609, ATCC 11828) belonging to different phylogroups differentially affect the cellular properties of cultured human keratinocytes in a strain-specific and dose-dependent manner. High doses of the pathogenic 889 and ATCC 11828 strains also resulted characteristic morphological changes and membrane damage, which lead to the cytotoxicity of human in vitro cultures keratinocytes (HPV-KER). Our aim was to further analyze the interaction of human in vitro cultured keratinocyes and identify bacterially-derived factors that may mediate the previously observed effects. In order to systematically quantify the P. acnes-induced cytotoxicity we performed spectrophotometric lactate dehydrogenase (LDH) and hemoglobin (HgB) assays using supernatant samples of bacterial treated HPV-KER cells and erythrocytes. The amount of released free LDH and HgB exhibited strain- and dose-dependent differences. We also noted the differential acidification of the pH in the culture supernatants. P. acnes is known to secrete propionic acid (PA), a characteristic, acidic end-product of bacterial fermentation in these species. In order to analyze whether P. acnes-derived PA has any role in the observed cellular changes we treated HPV KER cells with the acid and analyzed the cell morphology. Microscopic analysis of the PA treated cultures revealed cells with similar irregular membrane morphologies observed earlier upon high dose P. acnes 889 and ATCC 11828 treatments. Finally, we measured the amount of secreted short chain fatty acids (SCFA) in the P. acnes 889, 6609 and ATCC 11828-treated HPV-KER supernatant samples by mass spectrometry. These studies revealed marked differences in the amount of secreted PA; high dose treatment of the 889 and ATCC 11828 strains leading to higher levels. P. acnes-induced cellular changes depend on the type and amount of the applied bacterial strains. The observed differences may be due to variations of the amount of a secreted metabolic end-product, PA. Together with other bacterially-derived molecules it may be an active contributor of the P. acnes-induced cellular changes

Palladium Nanoparticle–Graphene Catalysts for Asymmetric Hydrogenation

We report for the first time the application of palladium nanoparticle-graphene (Pd/Gn) catalysts in the asymmetric hydrogenation of aliphatic a,b-unsaturated carboxylic acids using cinchonidine as chiral modifier. Pd/ Gns were prepared by deposition–precipitation from the aqueous phase over graphite oxide and subsequent simultaneous reduction of both the support and the metal precursor with NaBH4. The materials obtained were characterized by ICP optical emission spectroscopy, X-ray diffraction spectroscopy, Raman spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. We demonstrate that the Pd/Gns modified by cinchonidine can act as efficient catalysts in the asymmetric hydrogenation of a,b-unsaturated carboxylic acids for producing optically enriched saturated carboxylic acids

Polyploid Adipose Stem Cells Shift the Balance of IGF1/IGFBP2 to Promote the Growth of Breast Cancer

Background: The close proximity of adipose tissue and mammary epithelium predispose involvement of adipose cells in breast cancer development. Adipose-tissue stem cells (ASCs) contribute to tumor stroma and promote growth of cancer cells. In our previous study, we have shown that murine ASCs, which undergo polyploidization during their prolonged in vitro culturing, enhanced the proliferation of 4T1 murine breast cancer cells in IGF1 dependent manner. Aims: In the present study, our aim was to clarify the regulation of ASC-derived IGF1. Methods: 4T1 murine breast carcinoma cells were co-transplanted with visceral fat-derived ASCs (vASC) or with the polyploid ASC.B6 cell line into female BALB/c mice and tumor growth and lung metastasis were monitored. The conditioned media of vASCs and ASC.B6 cells were subjected to LC-MS/MS analysis and the production of IGFBP2 was verified by Western blotting. The regulatory effect was examined by adding recombinant IGFBP2 to the co-culture of ASC.B6 and 4T1. Akt/protein kinase B (PKB) activation was detected by Western blotting. Results: Polyploid ASCs promoted the tumor growth and metastasis more potently than vASCs with normal karyotype. vASCs produced the IGF1 regulator IGFBP2, which inhibited proliferation of 4T1 cells. Downregulation of IGFBP2 by polyploidization of ASCs and enhanced secretion of IGF1 allowed survival signaling in 4T1 cells, leading to Akt phosphorylation. Conclusions: Our results implicate that ASCs in the tumor microenvironment actively regulate the growth of breast cancer cells through the IGF/IGFBP system

Propionic Acid Produced by Propionibacterium acnes Strains Contri-butes to Their Pathogenicity

K

Propionsav szerepének vizsgálata a Propionibacterium acnes patogenicitásában

A Propionibacterium acnes (P. acnes) a bőr természetes mikroflórájának tagja, de speciális körülmények között opportunista patogénként hozzájárul gyulladásos bőrbetegségek kialakulásához. Munkacsoportunk korábbi eredményei alapján ismert, hogy különböző filogenetikai alcsoportokba tartozó P. acnes izolátumok (889, 6609, ATCC 11828) HPV-KER keratinocita sejtek sejtbiológiai sajátságaira gyakorolt hatása törzs- és dózis-specifikus sajátságokat mutat. Magas dózisban alkalmazott P. acnes 889 és ATCC 11828 kezelések hatására morfológiai változások és membránkárosodás figyelhetőek meg, melyek a HPV-KER sejtek fokozott pusztulását eredményezik. A fentebb említett megfigyelések mellet további összefüggést találtunk a sejtek morfológiai változásai, valamint a HPV-KER sejtek tenyésztő folyadékának elsavasodása között. Annak eldöntésére, hogy a megfigyelt hatások hátterében milyen tényezők szerepelhetnek, a HPV-KER sejteket eltérő mennyiségű propionsavval (PA) kezeltük. A PA kezelt sejtek mikroszkópos vizsgálata során hasonló morfológiai változásokat figyeltünk meg, mint korábban a P.acnes kezelt sejtek esetében. Ezen eredmények alapján feltételeztük, hogy a PA tehető felelőssé a megfigyelt membránkárosító hatásért. Hogy bizonyítsuk ezen feltevésünket, frissen szeparált humán eritrocitákat kezeltünk P. acnes 6609-es törzzsel PA hiányában illetve jelenlétében, és mértük a felülúszóban található szabad hemoglobin (HgB) mennyiségét. PA kezelés hatására dózisfüggően emelkedett a szabad HgB mennyisége, mely intenzívebb volt P. acnes 6609 kezelés mellett. Ezen törzs esetében nem volt megfigyelhető hasonló hatás a korábbi vizsgálataink során. Mindezen eredményeink arra utalnak, hogy dózis-, és törzs-specifikus különbségek figyelhetők meg egyes P. acnes klinikai izolátumok keratinociták sejtbiológiai folyamataira gyakorolt hatásában. A megfigyelt hatás hátterében a P. acnes törzsek eltérő metabolitikus aktivitása állhat, és a baktérium által termelt PA aktív szerepet tölthet be a P. acnes baktérium által kifejtett citotoxicitásban

Enantioselective Synthesis of 8-Hydroxyquinoline Derivative, Q134 as a Hypoxic Adaptation Inducing Agent

Hypoxia is a common feature of neurodegenerative diseases, including Alzheimer’s disease that may be responsible for disease pathogenesis and progression. Therefore, the hypoxia-inducible factor (HIF)1 system, responsible for hypoxic adaptation, is a potential therapeutic target to combat these diseases by activators of cytoprotective protein induction. We have selected a candidate molecule from our cytoprotective hydroxyquinoline library and developed a novel enantioselective synthesis for the production of its enantiomers. The use of quinidine or quinine as a catalyst enabled the preparation of enantiomer-pure products. We have utilized in vitro assays to evaluate cytoprotective activity, a fluorescence-activated cell sorting (FACS) based assay measuring mitochondrial membrane potential changes, and gene and protein expression analysis. Our data showed that the enantiomers of Q134 showed potent and similar activity in all tested assays. We have concluded that the enantiomers exert their cytoprotective activity via the HIF1 system through HIF1A protein stabilization

Single Cell Mass Cytometry Revealed the Immunomodulatory Effect of Cisplatin Via Downregulation of Splenic CD44+, IL-17A+ MDSCs and Promotion of Circulating IFN-γ+ Myeloid Cells in the 4T1 Metastatic Breast Cancer Model

The treatment of metastatic breast cancer remained a challenge despite the recent breakthrough in the immunotherapy regimens. Here, we addressed the multidimensional immunophenotyping of 4T1 metastatic breast cancer by the state-of-the-art single cell mass cytometry (CyTOF). We determined the dose and time dependent cytotoxicity of cisplatin on 4T1 cells by the xCelligence real-time electronic sensing assay. Cisplatin treatment reduced tumor growth, number of lung metastasis, and the splenomegaly of 4T1 tumor bearing mice. We showed that cisplatin inhibited the tumor stroma formation, the polarization of carcinoma-associated fibroblasts by the diminished proteolytic activity of fibroblast activating protein. The CyTOF analysis revealed the emergence of CD11b+/Gr-1+/CD44+ or CD11b+/Gr-1+/IL-17A+ myeloid-derived suppressor cells (MDSCs) and the absence of B220+ or CD62L+ B-cells, the CD62L+/CD4+ and CD62L+/CD8+ T-cells in the spleen of advanced cancer. We could show the immunomodulatory effect of cisplatin via the suppression of splenic MDSCs and via the promotion of peripheral IFN-γ+ myeloid cells. Our data could support the use of low dose chemotherapy with cisplatin as an immunomodulatory agent for metastatic triple negative breast cancer

Single Cell Mass Cytometry Revealed the Immunomodulatory Effect of Cisplatin Via Downregulation of Splenic CD44+, IL-17A+ MDSCs and Promotion of Circulating IFN-γ+ Myeloid Cells in the 4T1 Metastatic Breast Cancer Model

The treatment of metastatic breast cancer remained a challenge despite the recent breakthrough in the immunotherapy regimens. Here, we addressed the multidimensional immunophenotyping of 4T1 metastatic breast cancer by the state-of-the-art single cell mass cytometry (CyTOF). We determined the dose and time dependent cytotoxicity of cisplatin on 4T1 cells by the xCelligence real-time electronic sensing assay. Cisplatin treatment reduced tumor growth, number of lung metastasis, and the splenomegaly of 4T1 tumor bearing mice. We showed that cisplatin inhibited the tumor stroma formation, the polarization of carcinoma-associated fibroblasts by the diminished proteolytic activity of fibroblast activating protein. The CyTOF analysis revealed the emergence of CD11b+/Gr-1+/CD44+ or CD11b+/Gr-1+/IL-17A+ myeloid-derived suppressor cells (MDSCs) and the absence of B220+ or CD62L+ B-cells, the CD62L+/CD4+ and CD62L+/CD8+ T-cells in the spleen of advanced cancer. We could show the immunomodulatory effect of cisplatin via the suppression of splenic MDSCs and via the promotion of peripheral IFN-γ+ myeloid cells. Our data could support the use of low dose chemotherapy with cisplatin as an immunomodulatory agent for metastatic triple negative breast cancer