2018 study: increased plasma citrulline levels in pwMS

[jimmylegs]

the things about which i have no clue, include this (all i do know, is the body makes its own citrulline):

Plasma citrulline levels are increased in patients with multiple sclerosis (2018)
https://www.sciencedirect.com/science/a ... 0X18300832

Highlights
•Plasma citrulline levels are increased in patients with multiple sclerosis.
•Excess citrulline does not seem to result from breakdown of the brain MBP fraction.
•Alterations of NO metabolism in peripheral leukocytes might be related.
•No correlations were found with clinical nor radiological disease parameters.

Abstract
Background
Multiple sclerosis is an inflammatory demyelinating disorder of the central nervous system (CNS). Myelin basic protein (MBP), which is one of the main compounds of CNS myelin, appears to be hypercitrullinated in the brain of patients with MS. We hypothesized that MS is associated with an increased release of citrulline from the brain.

Methods
Twenty-five patients with MS, 25 controls without neurological disease (CwND) and 25 subjects with non-MS cerebral white matter lesions were included in this study. Groups were matched for age and gender. Clinical MS disability measures were recorded by means of Expanded Disability Status Scale (EDSS) scores and Multiple Sclerosis Severity Scores (MSSS). Citrulline was assessed in plasma obtained from an antecubital peripheral vein (PV) in all participants. Additional internal jugular vein (IJV) samples were examined in 10 patients with MS and 10 CwND. Twelve patients with MS underwent brain magnetic resonance imaging to determine total brain and T2 fluid-attenuated inversion recovery lesion volume.

Results
Median [IQR] PV citrulline levels were increased in patients with MS (50.47 [86.61] μM), as compared to CwND (33.58 [43.65] μM, P = 0.042) and subjects with non-MS cerebral white matter lesions (32.41 [28.86] μM, P = 0.006). Citrulline IJV levels and IJV/PV ratios were comparable between patients with MS and CwND. No significant correlations were found between PV citrulline levels and any of the clinical, nor radiological, disease measures.

Conclusion
PV plasma levels of citrulline are elevated in patients with MS but this does not seem to result from an augmented release from the brain. Increased plasma citrulline may be a promising new biomarker in MS but the origin and significance need to be further elucidated.

[Scott1]

Hi,

Presumably they are looking at the process described in this article

Argininosuccinate synthase: at the center of arginine metabolism.
https://www.ncbi.nlm.nih.gov/pubmed/21494411 (go to free full text).

It has a lot of useful diagrams that make sense once you're used to it. The problem will be the number of variables.

Regards,

[Leonard]

The citrullination mechanism is part of a programmed cell death. See eg http://www.thisisms.com/forum/general-d ... ml#p248066

This is yet another paper that confirms the overall picture at http://www.thisisms.com/forum/general-d ... ml#p251748