Levodopa-Associated Increase of Homocysteine Levels and Sural Axonal Neurodegeneration

Abstract

This electrophysiological sign of peripheral neuronal dysfunction may be circumstantial evidence suggesting that, to a certain extent, sensory nerve action potentials are a surrogate marker for the levodopa metabolism-induced elevation of homocysteine levels and the aggravation of the ongoing central neurodegenerative process.

Plasma Metabolomics Profiles in Prodromal and Clinical Parkinson's Disease

“…Interestingly, symmetric dimethylarginine (SDMA), a uremic toxin that inhibits NOS, was associated with a lower PD risk at 10 to 15 years before diagnosis. These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels 58,59 . Consistent with previous investigations, 35‐38,53 several lipids were associated with clinical PD, and these replicated in prodromal samples.…”

“…These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels. 58,59 Consistent with previous investigations, [35][36][37][38]53 several lipids were associated with clinical PD, and these replicated in prodromal samples. Overall, relative to controls, lipid metabolites tended to be reduced or even decreased over the course of PD, especially sphingomyelins and ceramides.…”

Plasma Metabolomics Profiles in Prodromal and Clinical Parkinson's Disease

“…Interestingly, symmetric dimethylarginine (SDMA), a uremic toxin that inhibits NOS, was associated with a lower PD risk at 10 to 15 years before diagnosis. These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels 58,59 . Consistent with previous investigations, 35‐38,53 several lipids were associated with clinical PD, and these replicated in prodromal samples.…”

“…These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels. 58,59 Consistent with previous investigations, [35][36][37][38]53 several lipids were associated with clinical PD, and these replicated in prodromal samples. Overall, relative to controls, lipid metabolites tended to be reduced or even decreased over the course of PD, especially sphingomyelins and ceramides.…”

Large-Fiber Neuropathy in Parkinson’s Disease: Clinical, Biological, and Electroneurographic Assessment of a Romanian Cohort

“…Muller et al, in 2004, found a significant correlation between the SNAP amplitude of the sural nerve and increased levels of homocysteine in PD patients undergoing long-term L-Dopa therapy [35]. In the present study, significant correlations between the aSNAP of the sural nerve and the superficial peroneal nerve to vitamin B12 and folate were found.…”

Subacute axonal neuropathy in Parkinson's disease with cobalamin and vitamin B6 deficiency under duodopa therapy

“…Although reduced amplitudes of sural nerve action potentials indicating axonal sensory PN have been reported in association with elevated Hcy‐levels, clinical neuropathy sum scores did not differ significantly between PD patients with normal and elevated Hcy‐levels 8. Furthermore, subacute development of PN as present in our patients has not been mentioned in association with elevated Hcy‐levels and normal cobalamin and vitamin B6 8…”

Plasma Metabolomics Profiles in Prodromal and Clinical Parkinson's Disease

“…Interestingly, symmetric dimethylarginine (SDMA), a uremic toxin that inhibits NOS, was associated with a lower PD risk at 10 to 15 years before diagnosis. These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels 58,59 . Consistent with previous investigations, 35‐38,53 several lipids were associated with clinical PD, and these replicated in prodromal samples.…”

“…These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels. 58,59 Consistent with previous investigations, [35][36][37][38]53 several lipids were associated with clinical PD, and these replicated in prodromal samples. Overall, relative to controls, lipid metabolites tended to be reduced or even decreased over the course of PD, especially sphingomyelins and ceramides.…”

Large-Fiber Neuropathy in Parkinson’s Disease: Clinical, Biological, and Electroneurographic Assessment of a Romanian Cohort

“…Muller et al, in 2004, found a significant correlation between the SNAP amplitude of the sural nerve and increased levels of homocysteine in PD patients undergoing long-term L-Dopa therapy [35]. In the present study, significant correlations between the aSNAP of the sural nerve and the superficial peroneal nerve to vitamin B12 and folate were found.…”

Subacute axonal neuropathy in Parkinson's disease with cobalamin and vitamin B6 deficiency under duodopa therapy

“…Although reduced amplitudes of sural nerve action potentials indicating axonal sensory PN have been reported in association with elevated Hcy‐levels, clinical neuropathy sum scores did not differ significantly between PD patients with normal and elevated Hcy‐levels 8. Furthermore, subacute development of PN as present in our patients has not been mentioned in association with elevated Hcy‐levels and normal cobalamin and vitamin B6 8…”

Plasma Metabolomics Profiles in Prodromal and Clinical Parkinson's Disease

“…Interestingly, symmetric dimethylarginine (SDMA), a uremic toxin that inhibits NOS, was associated with a lower PD risk at 10 to 15 years before diagnosis. These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels 58,59 . Consistent with previous investigations, 35‐38,53 several lipids were associated with clinical PD, and these replicated in prodromal samples.…”

“…These findings may indicate the involvement of endothelial function 55,56 and urea metabolism 57 in PD progression, and/or the initiation of levodopa treatment, which often increases homoarginine levels. 58,59 Consistent with previous investigations, [35][36][37][38]53 several lipids were associated with clinical PD, and these replicated in prodromal samples. Overall, relative to controls, lipid metabolites tended to be reduced or even decreased over the course of PD, especially sphingomyelins and ceramides.…”

Large-Fiber Neuropathy in Parkinson’s Disease: Clinical, Biological, and Electroneurographic Assessment of a Romanian Cohort

“…Muller et al, in 2004, found a significant correlation between the SNAP amplitude of the sural nerve and increased levels of homocysteine in PD patients undergoing long-term L-Dopa therapy [35]. In the present study, significant correlations between the aSNAP of the sural nerve and the superficial peroneal nerve to vitamin B12 and folate were found.…”

Subacute axonal neuropathy in Parkinson's disease with cobalamin and vitamin B6 deficiency under duodopa therapy

“…Although reduced amplitudes of sural nerve action potentials indicating axonal sensory PN have been reported in association with elevated Hcy‐levels, clinical neuropathy sum scores did not differ significantly between PD patients with normal and elevated Hcy‐levels 8. Furthermore, subacute development of PN as present in our patients has not been mentioned in association with elevated Hcy‐levels and normal cobalamin and vitamin B6 8…”