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Biology subjects

Bouma, H. R.

Publications and source records attributed to Bouma, H. R..

2 recordsLinked to original sources

Transient protein phosphorylation promotes disease tolerance to sepsis

One of the enduring paradoxes of sepsis is that organs fail despite little evidence of irreversible tissue injury. Emerging evidence suggests that this state reflects a regulated metabolic shutdown within host tissues, yet whether such hypometabolism contributes to pathology or promotes survival remains unclear. This phenomenon resembles torpor, a physiological state of profound hypometabolism induced by environmental stress and mediated through reversible protein phosphorylation. Septic hypometabolism is identified here as a conserved tissue-specific metabolic adaptation which is characterized by transient activation of Glycogen Synthase Kinase (GSK)3{beta}. This activation reduced disease severity of bacterial sepsis without affecting the hosts pathogen burden, indicating that GSK3{beta} activity promotes disease tolerance to infection. Consistent with these findings, plasma signatures associated with GSK3{beta} inhibition correlated with worse clinical outcomes in patients with sepsis. Together, these results define septic hypometabolism as a torpor-like response and identify reversible phosphorylation as a key mechanism governing host adaptation to severe bacterial infection.

immunology↗

Liver transcriptomic and methylomic analyses identify transcriptional MAPK regulation in facultative hibernation of Syrian hamster

Hibernation consist of alternating torpor/arousal phases, during which animals cope with repetitive hypothermia and ischemia-reperfusion. Due to limited transcriptomic and methylomic information for facultative hibernators, we here conducted RNA and whole genome bisulfite sequencing in liver of hibernating Syrian hamster (Mesocricetus auratus). Gene Ontology analysis was performed on 844 differentially expressed genes (DEGs) and confirmed the shift in metabolic fuel utilization, inhibition of RNA transcription and cell cycle regulation as found in seasonal hibernators. We show a so far unreported suppression of MAPK and PP1 pathways. Notably, hibernating hamsters showed upregulation of MAPK inhibitors (DUSPs and SPRYs) and reduced levels of MAPK induced transcription factors. Promoter methylation was found to modulate the expression of genes targeted by these transcription factors. In conclusion, we document gene regulation between hibernation phases, which may aid the identification of pathways and targets to prevent organ damage in transplantation or ischemia-reperfusion.

genomics↗