Noelia Rodriguez-Iglesias, Iñaki Paris, Jorge Valero, Lorena Cañas-Zabala, Alejandro Carretero, Klas Hatje, Jitao David Zhang, Christoph Patsch, Markus Britschgi, Simon Gutbier, Amanda Sierra
Phagocytosis is an indispensable function of microglia, the brain professional phagocytes. Microglia is particularly efficient phagocytosing cells that undergo programmed cell death (apoptosis) in physiological conditions. However, mounting evidence suggests microglial phagocytosis dysfunction in multiple brain disorders. These observations prompted us to search for phagocytosis modulators (enhancers or inhibitors) with therapeutic potential. We used a bottom-up strategy that consisted on the identification of phagocytosis modulators using phenotypic high throughput screenings (HTSs) in cell culture and validation in organotypic cultures and in vivo. We performed two complementary HTS campagnes: at Achucarro, we used primary cultures of mouse microglia and compounds of the Prestwick Chemical Library; at Roche, we used human iPSC derived macrophage-like cells and a proprietary chemo-genomic library with 2200 compounds with known mechanism-of-action. Next, we validated the more robust compounds using hippocampal organotypic cultures and identified two phagocytosis inhibitors: trifluoperazine, a dopaminergic and adrenergic antagonist used as an antipsychotic and antineoplastic; and deoxytubercidin, a ribose derivative. Finally, we tested whether these compounds were able to modulate phagocytosis of apoptotic newborn cells in the adult hippocampal neurogenic niche in vivo by administering them into the mouse hippocampus using osmotic minipumps. We confirmed that both trifluoperazine and deoxytubercidin have anti-phagocytic activity in vivo, and validated our bottom-up strategy to identify novel phagocytosis modulators. These results show that chemical libraries with annotated mechanism of action are an starting point for the pharmacological modulation of microglia in drug discovery projects aiming at the therapeutic manipulation of phagocytosis in brain diseases.
{"title":"A bottom-up approach identifies the antipsychotic and antineoplastic trifluoperazine and the ribose derivative deoxytubercidin as novel microglial phagocytosis inhibitors","authors":"Noelia Rodriguez-Iglesias, Iñaki Paris, Jorge Valero, Lorena Cañas-Zabala, Alejandro Carretero, Klas Hatje, Jitao David Zhang, Christoph Patsch, Markus Britschgi, Simon Gutbier, Amanda Sierra","doi":"10.1002/glia.24637","DOIUrl":"10.1002/glia.24637","url":null,"abstract":"<p>Phagocytosis is an indispensable function of microglia, the brain professional phagocytes. Microglia is particularly efficient phagocytosing cells that undergo programmed cell death (apoptosis) in physiological conditions. However, mounting evidence suggests microglial phagocytosis dysfunction in multiple brain disorders. These observations prompted us to search for phagocytosis modulators (enhancers or inhibitors) with therapeutic potential. We used a bottom-up strategy that consisted on the identification of phagocytosis modulators using phenotypic high throughput screenings (HTSs) in cell culture and validation in organotypic cultures and in vivo. We performed two complementary HTS campagnes: at Achucarro, we used primary cultures of mouse microglia and compounds of the Prestwick Chemical Library; at Roche, we used human iPSC derived macrophage-like cells and a proprietary chemo-genomic library with 2200 compounds with known mechanism-of-action. Next, we validated the more robust compounds using hippocampal organotypic cultures and identified two phagocytosis inhibitors: trifluoperazine, a dopaminergic and adrenergic antagonist used as an antipsychotic and antineoplastic; and deoxytubercidin, a ribose derivative. Finally, we tested whether these compounds were able to modulate phagocytosis of apoptotic newborn cells in the adult hippocampal neurogenic niche in vivo by administering them into the mouse hippocampus using osmotic minipumps. We confirmed that both trifluoperazine and deoxytubercidin have anti-phagocytic activity in vivo, and validated our bottom-up strategy to identify novel phagocytosis modulators. These results show that chemical libraries with annotated mechanism of action are an starting point for the pharmacological modulation of microglia in drug discovery projects aiming at the therapeutic manipulation of phagocytosis in brain diseases.</p>","PeriodicalId":174,"journal":{"name":"Glia","volume":"73 2","pages":"330-351"},"PeriodicalIF":5.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11662983/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142566905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mario Amatruda, Damien Marechal, Mar Gacias, Maureen Wentling, Sarah Turpin-Nolan, Johannes Morstein, Mohammed Moniruzzaman, Jens C. Brüning, Norman J. Haughey, Dirk H. Trauner, Patrizia Casaccia
Ceramide C16 is a sphingolipid detected at high levels in several neurodegenerative disorders, including multiple sclerosis (MS). It can be generated de novo or from the hydrolysis of other sphingolipids, such as sphingomyelin or through the recycling of sphingosine, in what is known as the salvage pathway. While the myelin damage occurring in MS suggests the importance of the hydrolytic and salvage pathways, the growing interest on the importance of diet in demyelinating disorders, prompted us to investigate the involvement of de novo ceramide C16 synthesis on disease severity. A diet rich in saturated fats such as palmitic acid, as found in many highly processed foods, provides substrates for the ceramide C16 synthetic enzymes ceramide synthase 6 (CERS6) and 5 (CERS5), which are expressed in the central nervous system. Using the experimental autoimmune encephalomyelitis (EAE) model of inflammatory demyelination, we show here that mice with CamK2a+ neuronal specific deletion of both CerS6 and CerS5 show a milder course of EAE than wild type mice, even when fed a diet enriched in palmitic acid. At a cellular level, neurons lacking both CerS6 and CerS5 are protected from the mitochondrial dysfunction arising from exposure to oxidative stress and palmitic acid in the medium. These data underscore the importance of a healthy diet avoiding processed foods for demyelinating disorders and identifies endogenous neuronal synthesis of ceramide C16 as an important determinant of disease severity.
{"title":"Neuroprotective effect of neuron-specific deletion of the C16 ceramide synthetic enzymes in an animal model of multiple sclerosis","authors":"Mario Amatruda, Damien Marechal, Mar Gacias, Maureen Wentling, Sarah Turpin-Nolan, Johannes Morstein, Mohammed Moniruzzaman, Jens C. Brüning, Norman J. Haughey, Dirk H. Trauner, Patrizia Casaccia","doi":"10.1002/glia.24631","DOIUrl":"10.1002/glia.24631","url":null,"abstract":"<p>Ceramide C16 is a sphingolipid detected at high levels in several neurodegenerative disorders, including multiple sclerosis (MS). It can be generated <i>de novo</i> or from the hydrolysis of other sphingolipids, such as sphingomyelin or through the recycling of sphingosine, in what is known as the salvage pathway. While the myelin damage occurring in MS suggests the importance of the hydrolytic and salvage pathways, the growing interest on the importance of diet in demyelinating disorders, prompted us to investigate the involvement of <i>de novo</i> ceramide C16 synthesis on disease severity. A diet rich in saturated fats such as palmitic acid, as found in many highly processed foods, provides substrates for the ceramide C16 synthetic enzymes ceramide synthase 6 (CERS6) and 5 (CERS5), which are expressed in the central nervous system. Using the experimental autoimmune encephalomyelitis (EAE) model of inflammatory demyelination, we show here that mice with <i>CamK2a</i>+ neuronal specific deletion of both <i>CerS6</i> and <i>CerS5</i> show a milder course of EAE than wild type mice, even when fed a diet enriched in palmitic acid. At a cellular level, neurons lacking both <i>CerS6</i> and <i>CerS5</i> are protected from the mitochondrial dysfunction arising from exposure to oxidative stress and palmitic acid in the medium. These data underscore the importance of a healthy diet avoiding processed foods for demyelinating disorders and identifies endogenous neuronal synthesis of ceramide C16 as an important determinant of disease severity.</p>","PeriodicalId":174,"journal":{"name":"Glia","volume":"73 2","pages":"271-290"},"PeriodicalIF":5.4,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11662985/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142566874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cong Wang, Jing Dong, Heng Huang, Kegui Zhou, Zhenguo Liu, Richard Milner, Longxuan Li
Cover Illustration: Representative images of immunofluorescent staining for glial fibrillary acidic protein (GFAP) (green), Iba-1(red) and DAPI (blue) in cultured primary astrocytes from TREM2-GFAP-knockout mice. Over 95% of the cultured cells were identified as astrocytes and no Iba-1 positive cells (microglia) were observed in the cultures. (See Li, L., et al, https://doi.org/10.1002/glia.24597)