Lipocalin 2 in the Paraventricular Thalamic Nucleus Contributes to DSS-Induced Depressive-Like Behaviors / 神经科学通报·英文版

The incidence rate of anxiety and depression is significantly higher in patients with inflammatory bowel diseases (IBD) than in the general population. The mechanisms underlying dextran sulfate sodium (DSS)-induced depressive-like behaviors are still unclear. We clarified that IBD mice induced by repeated administration of DSS presented depressive-like behaviors. The paraventricular thalamic nucleus (PVT) was regarded as the activated brain region by the number of c-fos-labeled neurons. RNA-sequencing analysis showed that lipocalin 2 (Lcn2) was upregulated in the PVT of mice with DSS-induced depressive behaviors. Upregulating Lcn2 from neuronal activity induced dendritic spine loss and the secreted protein induced chemokine expression and subsequently contributed to microglial activation leading to blood-brain barrier permeability. Moreover, Lcn2 silencing in the PVT alleviated the DSS-induced depressive-like behaviors. The present study demonstrated that elevated Lcn2 in the PVT is a critical factor for DSS-induced depressive behaviors.

Polymorphism of bovine lipocalin-2 gene and its impact on milk production traits and mastitis in Holstein Friesian cattle

Background: Mastitis is one of the most serious diseases of dairy cattle, causing substantial financial losses. While predisposition to reduced somatic cell count in milk has been considered for in cattle breeding programs as the key indicator of udder health status, scientists are seeking genetic markers of innate immune response, which could be helpful in selecting cows with improved immunity to mastitis. Lipocalin-2 (LCN2) is a protein involved in the response of the immune system by eliminating iron ions which are necessary for the growth of pathogenic bacteria, so LCN2 may be considered as a natural bacteriostatic agent and could become a marker of infection. Results: A total of five SNPs were identified in LCN2 gene (one in the promoter, three in exon 1, and one in intron 1). A single haplotype block was identified. The locus g.98793763GNC was found to have a significant impact on protein levels in milk, and alleles of this locus were identified to have a significant positive dominance effect on this trait. None of the four analysed loci had a statistically significant impact on the milk yield, fat levels in milk or the somatic cell score. LCN-2 gene had no significant impact on the incidence of mastitis in the cows. Conclusions: Although the identified SNPs were not found to have any impact on the somatic cell count or the incidence of mastitis in cows, it seems that further research is necessary, covering a larger population of cattle, to confirm the association between lipocalin-2 and milk production traits and mastitis.