Targeted Metabolomic Profiling Reveals Association Between Altered Amino Acids and Poor Functional Recovery After Stroke

Bad research, we don't need associations that 'may play' a role. We need defined protocols that deliver 100% recovery.

Targeted Metabolomic Profiling Reveals Association Between Altered Amino Acids and Poor Functional Recovery After Stroke

Xin Wang^1,2†, Tao Liu^1,3†, Haixin Song¹, Shaoyang Cui¹, Gang Liu¹, Andrea Christoforou¹, Patrick Flaherty⁴, Xun Luo⁵, Lisa Wood⁶ and Qing Mei Wang^1*

• ¹Stroke Biological Recovery Laboratory, Spaulding Rehabilitation Hospital, Boston, MA, United States
• ²Department of Rehabilitation, Clinical Medical College, Yangzhou University, Yangzhou, China
• ³Clinical School of Acupuncture, Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
• ⁴Department of Mathematics, College of Science and Mathematics, University of Massachusetts Boston, Boston, MA, United States
• ⁵Kerry Rehabilitation Medicine Research Institute, Shenzhen, China
• ⁶William F. Connell School of Nursing, Boston College, Chestnut Hill, MA, United States

Amino acids have been shown to be among the most important metabolites to be altered following stroke; however, they are a double-edged sword with regard to regulating hemostasis. In this study, we conducted a targeted metabolomic study to examine the association between serum levels of amino acids and functional recovery after stroke. Three hundred and fifty-one patients with stroke admitted to an acute rehabilitation hospital were screened, and 106 patients were selected based on inclusion and exclusion criteria. Recruited patients were stratified using Montebello Rehabilitation Factor Score (MRFS) efficiency. We selected the top (n = 20, 19%) and bottom (n = 20, 19%) of MRFS efficiency for metabolomic analysis. A total of 21 serum amino acids levels were measured using ultra high performance liquid chromatography and mass spectrometry. The normalized data were analyzed by multivariate approaches, and the selected potential biomarkers were combined in different combinations for prediction of stroke functional recovery. The results demonstrated that there were significant differences in leucine-isoleucine, proline, threonine, glutamic acid, and arginine levels between good and poor recovery groups. In the training (0.952) and test (0.835) sets, metabolite biomarker panels composed of proline, glutamic acid, and arginine had the highest sensitivity and specificity in distinguishing good recovery from poor. In particular, arginine was present in the top 10 combinations of the average area under the receiver operating characteristic curve (AUC) test set. Our findings suggest that amino acids related to energy metabolism and excitotoxicity may play an important role in functional recovery after stroke. Therefore, the level of serum arginine has predictive value for the recovery rate after stroke.