Aging Intensifies Myeloperoxidase Activity after Ischemic Stroke

Negin Jalali Motlagh1,2, Cuihua Wang1,2, Hyung-Hwan Kim3

  • 1Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02114, USA.

Aging and Disease
|September 26, 2024
PubMed

Insights

Aging exacerbates stroke damage by increasing myeloperoxidase (MPO) activity in the brain. Inhibiting MPO in aged mice improved neurological outcomes, suggesting new therapeutic targets for stroke patients.

Area of Science:

  • Neuroscience
  • Immunology
  • Aging Research

Background:

  • Oxidative stress is implicated in aging and diseases like stroke.
  • Myeloperoxidase (MPO) is a myeloid enzyme that generates oxidative stress and contributes to stroke damage.
  • The impact of aging on MPO activity and stroke outcomes remains understudied.

Purpose of the Study:

  • To investigate how aging affects MPO activity after ischemic stroke.
  • To determine the role of MPO in age-related stroke outcomes.
  • To explore MPO inhibition as a potential therapeutic strategy for aged stroke patients.

Main Methods:

  • Development and utilization of MPO Activatable Fluorescent Agent (MAFA) for imaging.
  • Comparison of stroke outcomes, mortality, and neuronal loss in young adult versus aged mice.
  • Assessment of MPO activity, Iba1+ cell counts, and MPO protein levels at different time points post-stroke.
  • Evaluation of the effects of MPO inhibition on neurobehavioral outcomes and mortality in aged mice.

Main Results:

  • Aged mice exhibited worse neurological outcomes, higher mortality, and increased neuronal loss after stroke compared to young adult mice.
  • MAFA imaging revealed significantly higher MPO activity in aged brains post-stroke.
  • Aged brains showed increased Iba1+ cells, with a decreased percentage of MPO+ cells, suggesting MPO release.
  • MPO inhibition in aged mice improved neurobehavioral outcomes and reduced mortality.

Conclusions:

  • Aging significantly increases MPO activity and exacerbates stroke-induced brain damage.
  • MPO plays a critical role in the adverse outcomes observed in aged individuals following ischemic stroke.
  • Targeting MPO activity presents a promising therapeutic avenue to mitigate age-related stroke complications.

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