Activation of proprotein convertase in the mouse habenula causes depressive-like behaviors through remodeling of extracellular matrix
NEUROPSYCHOPHARMACOLOGY
Authors: Ito, Hikaru; Nozaki, Kanako; Sakimura, Kenji; Abe, Manabu; Yamawaki, Shigeto; Aizawa, Hidenori
Abstract
The lateral habenula (LHb) attracts a growing interest as a regulator of monoaminergic activity which were frequently reported to be defective in depression. Here we found that chronic social defeat stress (CSDS) increased production of pro-inflammatory cytokines in LHb associated with mobilization of monocytes and remodeling of extracellular matrix by increased matrix metalloproteinase (MMP) activity. RNA-seq analysis identified proprotein convertasePcsk5as an upstream regulator of MMP activation, with upregulation in LHb neurons of mice with susceptibility to CSDS. PCSK5 facilitated motility of microglia in vitro by converting inactive pro-MMP14 and pro-MMP2 to their active forms, highlighting its role in mobilization of microglia and monocytes in neuroinflammation. Suppression ofPcsk5expression via small interfering RNA (siRNA) ameliorated depressive-like behaviors and pathological mobilization of monocytes in mice with susceptibility to CSDS. PCSK5-MMPs signaling pathway could be a target for development of the antidepressants targeting the inflammatory response in specific brain regions implicated in depression.
A genome-wide expression quantitative trait loci analysis of proprotein convertase subtilisin/kexin enzymes identifies a novel regulatory gene variant for FURIN expression and blood pressure
HUMAN GENETICS
Authors: Turpeinen, Hannu; Seppala, Ilkka; Lyytikainen, Leo-Pekka; Raitoharju, Emma; Hutri-Kahonen, Nina; Levula, Mari; Oksala, Niku; Waldenberger, Melanie; Klopp, Norman; Illig, Thomas; Mononen, Nina; Laaksonen, Reijo; Raitakari, Olli; Kahonen, Mika; Lehtimaki, Terho; Pesu, Marko
Abstract
Proprotein convertase subtilisin/kexin (PCSK) enzymes cleave and convert their immature substrates into biologically active forms. Polymorphisms in the PCSK genes have been reported to associate with human diseases and phenotypes, including hypercholesterolemia and blood pressure (BP), and targeting PCSKs is considered a promising future form of drug therapy. PCSK processing is readily induced upon upregulation of the enzyme, but the genetic factors contributing to PCSK expression have not been thoroughly characterized. To gain a comprehensive understanding of the genetic regulation of PCSK expression, we performed, for the first time, a genome-wide expression quantitative trait loci (eQTL) analysis using mRNA expression in > 1400 human peripheral blood samples from the Cardiovascular Risk in Young Finns Study and ca. ten million single-nucleotide polymorphisms (SNPs). The expression data showed clear expression for FURIN, PCSK5, PCSK7 and MBTPS1 (membrane-bound transcription factor peptidase, site 1) mRNAs in virtually all tested samples. A discovery analysis demonstrated a genome-wide significant (p < 5 x 10(-8)) association with the selected PCSK probes for 1024 variants, which were located at ten independent loci. Of these loci, 5/10 could be confirmed to regulate PCSK expression in two additional and independent sample sets. Finally, a phenotypic analysis demonstrated that a novel cis-eQTL SNP rs4702 for FURIN is strongly associated with both diastolic (p = 0.012) and systolic (p = 0.035) BP levels, as well as peripheral vascular resistance (p = 0.003). These findings indicate that the expression of the PCSK enzymes is regulated by genetic factors, which have biological roles in health and disease.