Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system with distinct subtypes, relapsing MS (RMS) and primary progressive MS (PPMS), which differ in clinical course an Show more
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system with distinct subtypes, relapsing MS (RMS) and primary progressive MS (PPMS), which differ in clinical course and underlying immunopathology. Cytokines are pleiotropic mediators of inflammatory and regenerative processes and are considered important contributors to the pathophysiology of MS. Ocrelizumab, a CD20-targeting monoclonal antibody, is approved for the treatment of patients with RMS and PPMS, yet its effects on circulating cytokines and neurotrophic factors remain incompletely understood. In this prospective observational study, 84 patients with MS (57 RMS, 27 PPMS) were analyzed regarding demographic data, disease activity and serum cytokine profiles before and 6 months after the start of ocrelizumab therapy. Baseline analyses revealed distinct cytokine signatures between patients with RMS and PPMS, with higher levels of several proinflammatory cytokines and chemokines in patients with RMS. Following ocrelizumab treatment, divergent cytokine profiles between patients with RMS and PPMS were partially attenuated, with significant modulation of Th1-associated chemokines and an increase in brain-derived neurotrophic factor (BDNF) observed in patients with RMS. In contrast, cytokine signatures in patients with PPMS remained largely unaffected by ocrelizumab treatment. Patients with RMS with disease activity during the first 6 months of ocrelizumab treatment showed a significant increase in different chemokines compared to baseline compared with patients without disease activity or those with PPMS. Our findings support divergent immunological mechanisms in RMS and PPMS, with a stronger cytokine-driven pathology and more pronounced immunomodulatory effects of ocrelizumab on the cytokine profile in patients with RMS. Show less
Schizophrenia is a chronic and severe mental disorder. It is currently treated with antipsychotic drugs (APD). However, APD's work only in a limited number of patients and may have cognition impairing Show more
Schizophrenia is a chronic and severe mental disorder. It is currently treated with antipsychotic drugs (APD). However, APD's work only in a limited number of patients and may have cognition impairing side effects. A growing body of evidence points out the potential involvement of abnormal sphingolipid metabolism in the pathophysiology of schizophrenia. Here, an analysis of human gene polymorphisms and brain gene expression in schizophrenia patients identified an association of SMPD1 and SMPD3 genes coding for acid- (ASM) and neutral sphingomyelinase-2 (NSM). In a rat model of psychosis using amphetamine hypersensitization, we found a locally restricted increase of ASM activity in the prefrontal cortex (PFC). Short-term haloperidol (HAL) treatment reversed behavioral symptoms and the ASM activity. A sphingolipidomic analysis confirmed an altered ceramide metabolism in the PFC during psychosis. Targeting enhanced ASM activity in a psychotic-like state with the ASM inhibitor KARI201 reversed psychotic like behavior and associated changes in the sphingolipidome. While effective HAL treatment led to locomotor decline and cognitive impairments, KARI201 did not. An RNA sequencing analysis of the PFC suggested a dysregulation of numerous schizophrenia related genes including Olig1, Fgfr1, Gpr17, Gna12, Abca2, Sox1, Dpm2, and Rab2a in the rat model of psychosis. HAL and KARI201 antipsychotic effects were associated with targeting expression of other schizophrenia associated genes like Col6a3, Slc22a8, and Bmal1, or Nr2f6a, respectively, but none affecting expression of sphingolipid regulating genes. Our data provide new insight into a potentially pathogenic mechanism of schizophrenia and suggest a new pharmaco-treatment strategy with reduced side effects. Show less