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ORIGINAL RESEARCH article

Front. Psychiatry

Sec. Addictive Disorders

Volume 16 - 2025 | doi: 10.3389/fpsyt.2025.1693270

This article is part of the Research TopicNeurobiological mechanisms of addiction: bridging Neuroscience and clinical implicationsView all 7 articles

Serum zonulin, brain-derived neurotrophic factor, and oxidative stress levels in individuals using paper (a4) impregnated with synthetic cannabinoids

Provisionally accepted
Sibel  KulaksızoğluSibel Kulaksızoğlu1*Ali  ErdoğanAli Erdoğan2Oğuzhan  TosunOğuzhan Tosun2Zeynep  Yaren GörgülüZeynep Yaren Görgülü2Esra  AcarEsra Acar2Yavuz  KireçYavuz Kireç2Sercan  KARABULUTSercan KARABULUT2Burak  KulaksızoğluBurak Kulaksızoğlu2Buket  CinemreBuket Cinemre2Özmen  MetinÖzmen Metin2
  • 1Antalya Eğitim ve Araştırma Hastanesi, Antalya, Türkiye
  • 2Akdeniz Universitesi Tip Fakultesi, Antalya, Türkiye

The final, formatted version of the article will be published soon.

Introduction: A4 is paper impregnated with synthetic cannabinoids, used as a novel psychoactive substance. The aim of this study was to investigate serum zonulin, brain-derived neurotrophic factor (BDNF), total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) in patients predominantly using synthetic cannabinoid-impregnated papers. Methods: Thirty patients with A4 use and 30 healthy volunteers (HC) were included. Peripheral blood was collected for zonulin, BDNF, TOS, TAS and OSI levels after 8-12 hours of fasting. Substance Craving Scale (SCS) was administered to the patient group. Results: Patients using A4 had lower BDNF levels (p=0.001) and higher TOS and OSI levels (p<0.001, p<0.001) compared to HC. Zonulin and TAS levels of both groups were similar (p>0.005 for both). No correlation was found between the SCS scores and zonulin, BDNF, TAS, TOS and OSI values (p>0.05 for all). When ROC analysis was performed, the cut-off value for BDNF in the patient group was ≤2.51 pg/mL, sensitivity was 66.7%, specificity was 63.3%, PPV was 76.0%, NPV was 76.0%, and area under the ROC curve was 0.744. The cut-off value for TOS was ≥14.51 μmol/L, sensitivity 70.0%, specificity 66.7%, PPV 77.7%, NPV 79.5%, area under the ROC curve 0.766. The cut-off value for OSI was ≥0.69, sensitivity 76.7%, specificity 63.3%, PPV 76.0%, NPV 81.3%, area under the ROC curve 0.773. Discussion: The findings suggest that A4 use may impair neuroplasticity and disrupt oxidative stress balance. BDNF, TOS, and OSI appear to be promising biomarker candidates for identifying individuals with A4 use.

Keywords: Synthetic cannabinoid, A4, Zonulin, BDNF, Oxidative Stress

Received: 26 Aug 2025; Accepted: 06 Oct 2025.

Copyright: © 2025 Kulaksızoğlu, Erdoğan, Tosun, Görgülü, Acar, Kireç, KARABULUT, Kulaksızoğlu, Cinemre and Metin. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Sibel Kulaksızoğlu, sblclngrgl@yahoo.co.uk

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