pp 1–7 | Cite as

Biomarkers of response to alpha-lipoic acid ± palmitoiletanolamide treatment in patients with diabetes and symptoms of peripheral neuropathy

  • Silvia Pieralice
  • Riccardo Vari
  • Alessandra Minutolo
  • Anna Rita Maurizi
  • Elvira Fioriti
  • Nicola Napoli
  • Paolo Pozzilli
  • Silvia Manfrini
  • Ernesto MaddaloniEmail author
Original Article



To evaluate the effect of oral alpha-lipoic acid (ALA) ± palmitoyl-ethanolamide (PEA) on neuropathic symptoms in patients with diabetic peripheral neuropathy (DPN) and to identify factors related to the efficacy of the treatment.


This is a retrospective observational pilot study evaluating 49 patients with diabetes and positive Neuropathy Symptoms Score (NSS). Clinical and biochemical variables, including NSS, were compared between untreated patients and patients treated with oral 600 mg/day ALA ± 600 mg/day PEA at baseline (first occurrence of NSS ≥ 3) and at least 2 months after baseline. Number of days between treatment initiation and symptoms’ relief and related factors were also investigated.


Thirty subjects were treated with ALA ± PEA and 19 subjects did not receive any specific treatment for neuropathy symptoms. Follow-up visits occurred after 98 ± 46 days. NSS significantly decreased in patients treated with ALA ± PEA (5.4 ± 1.3 at baseline vs. 1.7 ± 2.4 at follow-up, p < 0.001), but not in untreated patients (p = 0.164). Subjects treated with ALA ± PEA reported a mean time from treatment initiation to symptoms’ relief of 18.4 ± 9.0 days. The number of days of treatment needed for symptoms’ relief was inversely related to HDL-cholesterol levels (r = −0.503, p = 0.010) and to eGFR (r = −0.428, p = 0.033), whereas there was no significant relationship between time to symptoms’ relief and age, HbA1c, lipid profile and the severity of symptoms at baseline.


This study documents that oral administration of ALA ± PEA helps in controlling neuropathy symptoms in diabetes. Moreover, our data show that higher HDL-c levels and better renal function are associated to a faster therapeutic effect, suggesting them as biomarkers of response to therapy with ALA ± PEA.


Diabetic neuropathy Alpha-lipoic acid Palmitoiletanolamide PEA, HDL 



This study was in part supported by an unrestricted grant from LJ Pharma.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was approved by the ethics committee of Campus Bio-Medico University of Rome, Italy. For this retrospective study, formal consent is not required. No patient identifiable information has been used in this study and only data from which identifying factors have been removed were used for statistical analysis.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Silvia Pieralice
    • 1
  • Riccardo Vari
    • 1
  • Alessandra Minutolo
    • 1
  • Anna Rita Maurizi
    • 1
  • Elvira Fioriti
    • 1
  • Nicola Napoli
    • 1
  • Paolo Pozzilli
    • 1
  • Silvia Manfrini
    • 1
  • Ernesto Maddaloni
    • 1
    Email author
  1. 1.Department of Medicine, Unit of Endocrinology and DiabetesCampus Bio-Medico University of RomeRomeItaly

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