Cystatin C expression in ischemic white matter lesions

Area of Science:

• Neuroscience
• Biochemistry
• Pathology

Background:

• Ischemic white matter lesions (WMLs) are a significant component of cerebrovascular disease.
• Cystatin C, a cysteine protease inhibitor, has potential roles in neuroinflammation and neurodegeneration.
• Understanding the molecular mechanisms underlying WML progression is crucial for developing therapeutic strategies.

Purpose of the Study:

• To investigate the association between cystatin C levels and the progression of ischemic white matter lesions (WMLs).
• To explore the cellular source and regulation of cystatin C within the white matter.

Main Methods:

• Cerebrospinal fluid (CSF) cystatin C levels were measured in patients with varying WML severity.
• Immunohistochemical analysis of cystatin C in white matter tissue from patients and controls.
• In vitro studies using human neural cell cultures to assess cystatin C expression and production.

Main Results:

• CSF cystatin C levels were significantly lower in patients with severe WMLs (Fazekas grade 3) compared to those with mild or no lesions.
• Cystatin C immunoreactivity was detected in astrocytes, and a reduced number of astrocytes was observed in the white matter of patients with severe WMLs.
• In vitro, thrombin stimulation significantly increased cystatin C production and secretion by astrocytes.

Conclusions:

• Reduced CSF cystatin C levels in ischemic WMLs may be attributed to a decreased number of cystatin C-secreting astrocytes.
• Astrocytes play a role in cystatin C production within the white matter, potentially influenced by proteases and inflammatory cytokines.