Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes
Background: Phenol-soluble modulins (PSMs) are pore-forming toxins (PFTs) produced by staphylococci. PSMs exert diverse cellular effects, including lytic, pro-apoptotic, pro-inflammatory and antimicrobial actions. Since the effects of PSMs on autophagy have not yet been reported, we evaluated the au...
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MDPI AG
2023-11-01
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| Series: | Biomedicines |
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| Online Access: | https://www.mdpi.com/2227-9059/11/11/3018 |
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| author | Áron Dernovics György Seprényi Zsolt Rázga Ferhan Ayaydin Zoltán Veréb Klára Megyeri |
| author_facet | Áron Dernovics György Seprényi Zsolt Rázga Ferhan Ayaydin Zoltán Veréb Klára Megyeri |
| author_sort | Áron Dernovics |
| collection | DOAJ |
| description | Background: Phenol-soluble modulins (PSMs) are pore-forming toxins (PFTs) produced by staphylococci. PSMs exert diverse cellular effects, including lytic, pro-apoptotic, pro-inflammatory and antimicrobial actions. Since the effects of PSMs on autophagy have not yet been reported, we evaluated the autophagic activity in HaCaT keratinocytes treated with recombinant PSMα3. Methods: The autophagic flux and levels of autophagic marker proteins were determined using Western blot analysis. Subcellular localization of LC3B and Beclin-1 was investigated using an indirect immunofluorescence assay. The ultrastructural features of control and PSMα3-treated cells were evaluated via transmission electron microscopy. Cytoplasmic acidification was measured via acridine orange staining. Phosphorylation levels of protein kinases, implicated in autophagy regulation, were studied using a phospho-kinase array and Western blot analysis. Results: PSMα3 facilitated the intracellular redistribution of LC3B, increased the average number of autophagosomes per cell, promoted the development of acidic vesicular organelles, elevated the levels of LC3B-II, stimulated autophagic flux and triggered a significant decrease in the net autophagic turnover rate. PSMα3 induced the accumulation of autophagosomes/autolysosomes, amphisomes and multilamellar bodies at the 0.5, 6 and 24 h time points, respectively. The phospho-Akt1/2/3 (T308 and S473), and phospho-mTOR (S2448) levels were decreased, whereas the phospho-Erk1/2 (T202/Y204 and T185/Y187) level was increased in PSMα3-treated cells. Conclusions: In HaCaT keratinocytes, PSMα3 stimulates autophagy. The increased autophagic activity elicited by sub-lytic PSM concentrations might be an integral part of the cellular defense mechanisms protecting skin homeostasis. |
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| language | English |
| last_indexed | 2024-03-09T16:59:59Z |
| publishDate | 2023-11-01 |
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| series | Biomedicines |
| spelling | doaj.art-759fcb9385484133900e1ccca9a581bc2023-11-24T14:31:11ZengMDPI AGBiomedicines2227-90592023-11-011111301810.3390/biomedicines11113018Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT KeratinocytesÁron Dernovics0György Seprényi1Zsolt Rázga2Ferhan Ayaydin3Zoltán Veréb4Klára Megyeri5Department of Medical Microbiology, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 10., H-6720 Szeged, HungaryDepartment of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Kossuth L. sgt. 40., H-6724 Szeged, HungaryDepartment of Pathology, University of Szeged, Állomás u. 2, H-6720 Szeged, HungaryHungarian Centre of Excellence for Molecular Medicine (HCEMM) Nonprofit Ltd., Római krt. 21., H-6723 Szeged, HungaryRegenerative Medicine and Cellular Pharmacology Laboratory, Department of Dermatology and Allergology, University of Szeged, Korányi Fasor 6, H-6720 Szeged, HungaryDepartment of Medical Microbiology, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 10., H-6720 Szeged, HungaryBackground: Phenol-soluble modulins (PSMs) are pore-forming toxins (PFTs) produced by staphylococci. PSMs exert diverse cellular effects, including lytic, pro-apoptotic, pro-inflammatory and antimicrobial actions. Since the effects of PSMs on autophagy have not yet been reported, we evaluated the autophagic activity in HaCaT keratinocytes treated with recombinant PSMα3. Methods: The autophagic flux and levels of autophagic marker proteins were determined using Western blot analysis. Subcellular localization of LC3B and Beclin-1 was investigated using an indirect immunofluorescence assay. The ultrastructural features of control and PSMα3-treated cells were evaluated via transmission electron microscopy. Cytoplasmic acidification was measured via acridine orange staining. Phosphorylation levels of protein kinases, implicated in autophagy regulation, were studied using a phospho-kinase array and Western blot analysis. Results: PSMα3 facilitated the intracellular redistribution of LC3B, increased the average number of autophagosomes per cell, promoted the development of acidic vesicular organelles, elevated the levels of LC3B-II, stimulated autophagic flux and triggered a significant decrease in the net autophagic turnover rate. PSMα3 induced the accumulation of autophagosomes/autolysosomes, amphisomes and multilamellar bodies at the 0.5, 6 and 24 h time points, respectively. The phospho-Akt1/2/3 (T308 and S473), and phospho-mTOR (S2448) levels were decreased, whereas the phospho-Erk1/2 (T202/Y204 and T185/Y187) level was increased in PSMα3-treated cells. Conclusions: In HaCaT keratinocytes, PSMα3 stimulates autophagy. The increased autophagic activity elicited by sub-lytic PSM concentrations might be an integral part of the cellular defense mechanisms protecting skin homeostasis.https://www.mdpi.com/2227-9059/11/11/3018pore-forming toxinstaphylococciphenol-soluble modulinautophagykeratinocyte |
| spellingShingle | Áron Dernovics György Seprényi Zsolt Rázga Ferhan Ayaydin Zoltán Veréb Klára Megyeri Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes Biomedicines pore-forming toxin staphylococci phenol-soluble modulin autophagy keratinocyte |
| title | Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes |
| title_full | Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes |
| title_fullStr | Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes |
| title_full_unstemmed | Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes |
| title_short | Phenol-Soluble Modulin α3 Stimulates Autophagy in HaCaT Keratinocytes |
| title_sort | phenol soluble modulin α3 stimulates autophagy in hacat keratinocytes |
| topic | pore-forming toxin staphylococci phenol-soluble modulin autophagy keratinocyte |
| url | https://www.mdpi.com/2227-9059/11/11/3018 |
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