@article{GorlovaSvirinPavlovetal.2023, author = {Gorlova, Anna and Svirin, Evgeniy and Pavlov, Dmitrii and Cespuglio, Raymond and Proshin, Andrey and Schroeter, Careen A. and Lesch, Klaus-Peter and Strekalova, Tatyana}, title = {Understanding the role of oxidative stress, neuroinflammation and abnormal myelination in excessive aggression associated with depression: recent input from mechanistic studies}, series = {International Journal of Molecular Sciences}, volume = {24}, journal = {International Journal of Molecular Sciences}, number = {2}, issn = {1422-0067}, doi = {10.3390/ijms24020915}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304917}, year = {2023}, abstract = {Aggression and deficient cognitive control problems are widespread in psychiatric disorders, including major depressive disorder (MDD). These abnormalities are known to contribute significantly to the accompanying functional impairment and the global burden of disease. Progress in the development of targeted treatments of excessive aggression and accompanying symptoms has been limited, and there exists a major unmet need to develop more efficacious treatments for depressed patients. Due to the complex nature and the clinical heterogeneity of MDD and the lack of precise knowledge regarding its pathophysiology, effective management is challenging. Nonetheless, the aetiology and pathophysiology of MDD has been the subject of extensive research and there is a vast body of the latest literature that points to new mechanisms for this disorder. Here, we overview the key mechanisms, which include neuroinflammation, oxidative stress, insulin receptor signalling and abnormal myelination. We discuss the hypotheses that have been proposed to unify these processes, as many of these pathways are integrated for the neurobiology of MDD. We also describe the current translational approaches in modelling depression, including the recent advances in stress models of MDD, and emerging novel therapies, including novel approaches to management of excessive aggression, such as anti-diabetic drugs, antioxidant treatment and herbal compositions.}, language = {en} } @article{SvirinVeniaminovaCostaNunesetal.2022, author = {Svirin, Evgeniy and Veniaminova, Ekaterina and Costa-Nunes, Jo{\~a}o Pedro and Gorlova, Anna and Umriukhin, Aleksei and Kalueff, Allan V. and Proshin, Andrey and Anthony, Daniel C. and Nedorubov, Andrey and Tse, Anna Chung Kwan and Walitza, Susanne and Lim, Lee Wei and Lesch, Klaus-Peter and Strekalova, Tatyana}, title = {Predation stress causes excessive aggression in female mice with partial genetic inactivation of tryptophan hydroxylase-2: evidence for altered myelination-related processes}, series = {Cells}, volume = {11}, journal = {Cells}, number = {6}, issn = {2073-4409}, doi = {10.3390/cells11061036}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-267250}, year = {2022}, abstract = {The interaction between brain serotonin (5-HT) deficiency and environmental adversity may predispose females to excessive aggression. Specifically, complete inactivation of the gene encoding tryptophan hydroxylase-2 (Tph2) results in the absence of neuronal 5-HT synthesis and excessive aggressiveness in both male and female null mutant (Tph2\(^{-/-}\)) mice. In heterozygous male mice (Tph2\(^{+/-}\)), there is a moderate reduction in brain 5-HT levels, and when they are exposed to stress, they exhibit increased aggression. Here, we exposed female Tph2\(^{+/-}\) mice to a five-day rat predation stress paradigm and assessed their emotionality and social interaction/aggression-like behaviors. Tph2\(^{+/-}\) females exhibited excessive aggression and increased dominant behavior. Stressed mutants displayed altered gene expression of the 5-HT receptors Htr1a and Htr2a, glycogen synthase kinase-3 β (GSK-3β), and c-fos as well as myelination-related transcripts in the prefrontal cortex: myelin basic protein (Mbp), proteolipid protein 1 (Plp1), myelin-associated glycoprotein (Mag), and myelin oligodendrocyte glycoprotein (Mog). The expression of the plasticity markers synaptophysin (Syp) and cAMP response element binding protein (Creb), but not AMPA receptor subunit A2 (GluA2), were affected by genotype. Moreover, in a separate experiment, na{\"i}ve female Tph2\(^{+/-}\) mice showed signs of enhanced stress resilience in the modified swim test with repeated swimming sessions. Taken together, the combination of a moderate reduction in brain 5-HT with environmental challenges results in behavioral changes in female mice that resemble the aggression-related behavior and resilience seen in stressed male mutants; additionally, the combination is comparable to the phenotype of null mutants lacking neuronal 5-HT. Changes in myelination-associated processes are suspected to underpin the molecular mechanisms leading to aggressive behavior.}, language = {en} } @article{TianeSchepersRombautetal.2019, author = {Tiane, Assia and Schepers, Melissa and Rombaut, Ben and Hupperts, Raymond and Prickaerts, Jos and Hellings, Niels and van den Hove, Daniel and Vanmierlo, Tim}, title = {From OPC to oligodendrocyte: an epigenetic journey}, series = {Cells}, volume = {8}, journal = {Cells}, number = {10}, issn = {2073-4409}, doi = {10.3390/cells8101236}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193267}, year = {2019}, abstract = {Oligodendrocytes provide metabolic and functional support to neuronal cells, rendering them key players in the functioning of the central nervous system. Oligodendrocytes need to be newly formed from a pool of oligodendrocyte precursor cells (OPCs). The differentiation of OPCs into mature and myelinating cells is a multistep process, tightly controlled by spatiotemporal activation and repression of specific growth and transcription factors. While oligodendrocyte turnover is rather slow under physiological conditions, a disruption in this balanced differentiation process, for example in case of a differentiation block, could have devastating consequences during ageing and in pathological conditions, such as multiple sclerosis. Over the recent years, increasing evidence has shown that epigenetic mechanisms, such as DNA methylation, histone modifications, and microRNAs, are major contributors to OPC differentiation. In this review, we discuss how these epigenetic mechanisms orchestrate and influence oligodendrocyte maturation. These insights are a crucial starting point for studies that aim to identify the contribution of epigenetics in demyelinating diseases and may thus provide new therapeutic targets to induce myelin repair in the long run.}, language = {en} } @article{HornBaumannPereiraetal.2012, author = {Horn, Michael and Baumann, Reto and Pereira, Jorge A. and Sidiropoulos, P{\´a}ris N. M. and Somandin, Christian and Welzl, Hans and Stendel, Claudia and L{\"u}hmann, Tessa and Wessig, Carsten and Toyka, Klaus V. and Relvas, Jo{\~a}o B. and Senderek, Jan and Suter, Ueli}, title = {Myelin is dependent on the Charcot-Marie-Tooth Type 4H disease culprit protein FRABIN/FGD4 in Schwann cells}, series = {Brain}, volume = {135}, journal = {Brain}, doi = {10.1093/brain/aws275}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125390}, pages = {3567-3583}, year = {2012}, abstract = {Studying the function and malfunction of genes and proteins associated with inherited forms of peripheral neuropathies has provided multiple clues to our understanding of myelinated nerves in health and disease. Here, we have generated a mouse model for the peripheral neuropathy Charcot-Marie-Tooth disease type 4H by constitutively disrupting the mouse orthologue of the suspected culprit gene FGD4 that encodes the small RhoGTPase Cdc42-guanine nucleotide exchange factor Frabin. Lack of Frabin/Fgd4 causes dysmyelination in mice in early peripheral nerve development, followed by profound myelin abnormalities and demyelination at later stages. At the age of 60 weeks, this was accompanied by electrophysiological deficits. By crossing mice carrying alleles of Frabin/Fgd4 flanked by loxP sequences with animals expressing Cre recombinase in a cell type-specific manner, we show that Schwann cell-autonomous Frabin/Fgd4 function is essential for proper myelination without detectable primary contributions from neurons. Deletion of Frabin/Fgd4 in Schwann cells of fully myelinated nerve fibres revealed that this protein is not only required for correct nerve development but also for accurate myelin maintenance. Moreover, we established that correct activation of Cdc42 is dependent on Frabin/Fgd4 function in healthy peripheral nerves. Genetic disruption of Cdc42 in Schwann cells of adult myelinated nerves resulted in myelin alterations similar to those observed in Frabin/Fgd4-deficient mice, indicating that Cdc42 and the Frabin/Fgd4-Cdc42 axis are critical for myelin homeostasis. In line with known regulatory roles of Cdc42, we found that Frabin/Fgd4 regulates Schwann cell endocytosis, a process that is increasingly recognized as a relevant mechanism in peripheral nerve pathophysiology. Taken together, our results indicate that regulation of Cdc42 by Frabin/Fgd4 in Schwann cells is critical for the structure and function of the peripheral nervous system. In particular, this regulatory link is continuously required in adult fully myelinated nerve fibres. Thus, mechanisms regulated by Frabin/Fgd4-Cdc42 are promising targets that can help to identify additional regulators of myelin development and homeostasis, which may crucially contribute also to malfunctions in different types of peripheral neuropathies.}, language = {en} }