RT Journal Article SR Electronic T1 Lowering Plasma 1-Deoxysphingolipids Improves Neuropathy in Diabetic Rats JF Diabetes JO Diabetes FD American Diabetes Association SP 1035 OP 1045 DO 10.2337/db14-1325 VO 64 IS 3 A1 Othman, Alaa A1 Bianchi, Roberto A1 Alecu, Irina A1 Wei, Yu A1 Porretta-Serapiglia, Carla A1 Lombardi, Raffaella A1 Chiorazzi, Alessia A1 Meregalli, Cristina A1 Oggioni, Norberto A1 Cavaletti, Guido A1 Lauria, Giuseppe A1 von Eckardstein, Arnold A1 Hornemann, Thorsten YR 2015 UL http://diabetes.diabetesjournals.org/content/64/3/1035.abstract AB 1-Deoxysphingolipids (1-deoxySLs) are atypical neurotoxic sphingolipids that are formed by the serine-palmitoyltransferase (SPT). Pathologically elevated 1-deoxySL concentrations cause hereditary sensory and autonomic neuropathy type 1 (HSAN1), an axonal neuropathy associated with several missense mutations in SPT. Oral L-serine supplementation suppressed the formation of 1-deoxySLs in patients with HSAN1 and preserved nerve function in an HSAN1 mouse model. Because 1-deoxySLs also are elevated in patients with type 2 diabetes mellitus, L-serine supplementation could also be a therapeutic option for diabetic neuropathy (DN). This was tested in diabetic STZ rats in a preventive and therapeutic treatment scheme. Diabetic rats showed significantly increased plasma 1-deoxySL concentrations, and L-serine supplementation lowered 1-deoxySL concentrations in both treatment schemes (P < 0.0001). L-serine had no significant effect on hyperglycemia, body weight, or food intake. Mechanical sensitivity was significantly improved in the preventive (P < 0.01) and therapeutic schemes (P < 0.001). Nerve conduction velocity (NCV) significantly improved in only the preventive group (P < 0.05). Overall NCV showed a highly significant (P = 5.2E-12) inverse correlation with plasma 1-deoxySL concentrations. In summary, our data support the hypothesis that 1-deoxySLs are involved in the pathology of DN and that an oral L-serine supplementation could be a novel therapeutic option for treating DN.