Haloperidol Abrogates Matrix Metalloproteinase-9 Expression by Inhibition of NF-κB Activation in Stimulated Human Monocytic Cells

Association between C-reactive protein levels and antipsychotic treatment during 12 months follow-up period after acute psychosis

BACKGROUND

A potential role of inflammatory pathways in the pathology of schizophrenia has been suggested for at least a subgroup of patients. Elevated levels of the inflammatory marker C-reactive protein (CRP) have been observed, with associations to pathogenesis and symptoms. The current evidence regarding effects of antipsychotics on CRP levels is ambiguous.

OBJECTIVES

To examine and compare the influence on CRP levels of three pharmacologically diverse new generation antipsychotics during a one-year follow-up in schizophrenia spectrum disorder.

METHODS

In a multicenter, pragmatic and rater-blinded randomized trial, the effects of amisulpride, aripiprazole and olanzapine were compared in 128 patients with schizophrenia spectrum disorder. All had positive symptoms of psychosis at study entry. Clinical and laboratory assessments including the measurement of CRP levels were conducted at baseline, and 1, 3, 6, 12, 26, 39, and 52 weeks thereafter.

RESULTS

For all antipsychotic drugs analysed together, there was an increase in CRP levels during the one-year follow-up. Aripiprazole, as opposed to amisulpride and olanzapine, was associated with a reduced CRP level after one week, after which the CRP level caught up with the other drugs. Compared to those previously exposed to antipsychotic drugs, antipsychotic-naïve patients had lower CRP levels at all follow-up time points, but with the same temporal patterns of change.

CONCLUSION

Treatment with amisulpride, aripiprazole and olanzapine showed different effects on CRP levels in patients with schizophrenia spectrum disorders, modified by previous antipsychotics exposure status. This finding suggests that antipsychotic drugs may vary with respect to their influence on pro-inflammatory pathways.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT01446328; URL: http://www.

CLINICALTRIALS

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Proteome Analysis of PC12 Cells Reveals Alterations in Translation Regulation and Actin Signaling Induced by Clozapine

Although antipsychotics are routinely used in the treatment of schizophrenia for the last decades, their precise mechanism of action is still unclear. In this study, we investigated changes in the PC12 cells’ proteome under the influence of clozapine, risperidone, and haloperidol to identify protein pathways regulated by antipsychotics. Analysis of the protein profiles in two time points: after 12 and 24 h of incubation with drugs revealed significant alterations in 510 proteins. Further canonical pathway analysis revealed an inhibition of ciliary trophic factor signaling after treatment with haloperidol and showed a decrease in acute phase response signaling in the risperidone group. Interestingly, all tested drugs have caused changes in PC12 proteome which correspond to inhibition of cytokines: tumor necrosis factor (TNF) and transforming growth factor beta 1 (TGF-β1). We also found that the 12-h incubation with clozapine caused up-regulation of protein kinase A signaling and translation machinery. After 24 h of treatment with clozapine, the inhibition of the actin cytoskeleton signaling and Rho proteins signaling was revealed. The obtained results suggest that the mammalian target of rapamycin complex 1 (mTORC1) and 2 (mTORC2) play a central role in the signal transduction of clozapine.

HADC8 Inhibitor WK2-16 Therapeutically Targets Lipopolysaccharide-Induced Mouse Model of Neuroinflammation and Microglial Activation

Glial activation and neuroinflammatory processes play important roles in the pathogenesis of brain abscess and neurodegenerative diseases. Activated glial cells can secrete various proinflammatory cytokines and neurotoxic mediators, which contribute to the exacerbation of neuronal cell death. The inhibition of glial activation has been shown to alleviate neurodegenerative conditions. The present study was to investigate the specific HDAC8 inhibitor WK2-16, especially its effects on the neuroinflammatory responses through glial inactivation. WK2-16 significantly reduced the gelatinolytic activity of MMP-9, and expression of COX-2/iNOS proteins in striatal lipopolysaccharide (LPS)-induced neuroinflammation in C57BL/6 mice. The treatment of WK2-16 markedly improved neurobehavioral deficits. Immunofluorescent staining revealed that WK2-16 reduced LPS-stimulated astrogliosis and microglial activation in situ. Consistently, cellular studies revealed that WK2-16 significantly suppressed LPS-induced mouse microglia BV-2 cell proliferation. WK2-16 was proven to concentration-dependently induce the levels of acetylated SMC3 in microglial BV-2 cells. It also reduced the expression of COX-2/iNOS proteins and TNF-α production in LPS-activated microglial BV-2 cells. The signaling studies demonstrated that WK2-16 markedly inhibited LPS-activated STAT-1/-3 and Akt activation, but not NF-κB or MAPK signaling. In summary, the HDAC8 inhibitor WK2-16 exhibited neuroprotective effects through its anti-neuroinflammation and glial inactivation properties, especially in microglia in vitro and in vivo.