本研究旨在确定血清脑源性神经营养因子（BDNF）水平对COVID-19患者神经系统疾病发展的影响，并探讨氧化应激和炎症在其中的可能作用。本次病例对照研究纳入了伊朗阿瓦兹Golestan和Sina医院进行治疗的42名COVID-19患者。患者被分为具有（n = 18）和不具有（n = 24）神经疾病的实验组和对照组。在采集血液样本后，分离血清并将其在-80°C冷冻保存，待用于测量BDNF、氧化应激指标和炎症因子的生化评估。 尽管COVID-19患者中未观察到明显的脑损伤，但结果显示，与对照组相比，实验组的血清BDNF水平增加，并伴随着血清中肿瘤坏死因子-alpha（TNF-α）水平的增加和干扰素-γ（IFN-γ）水平的降低。此外，与对照组相比，实验组患者的血清中硫醇水平降低，丙二醛（MDA）水平增加。此外，实验组的血清BDNF浓度与一氧化氮（NO）呈显著正相关。 使用包含硫醇相关剂或其他抗氧化剂的非处方药品可缓解COVID-19患者神经症状相关的氧化应激和炎症增加。

The aim of this study was to determine the effect of serum level of brain-derived neurotrophic factor (BDNF) on the development of neurological disorders in COVID-19 patients and the probable role of oxidative stress and inflammation in this phenomenon.The present case-control study included 42 COVID-19 patients referring to Golestan and Sina hospitals of Ahvaz, Iran, for treatment. Patients with (n = 18) and without (n = 24) neurological disorders were allocated into test and control groups, respectively. Following blood sampling, serum isolation was done, and the serum was stored at -80°C until biochemical assessment for measuring BDNF, oxidative stress indices, and inflammatory factors.Although no significant brain damage was observed in the COVID-19 patients with neurological disorders, the results showed that the serum level of BDNF in the test group increased compared to that in the control group, and this increment was accompanied with increased Tumor Necrosis Factor-alpha (TNF-α) and decreased Interferon gamma (IFN-γ) levels in the serum. Moreover, compared to the control group, patients in the test group had a decreased level of Thiol and an increased level of Malondialdehyde (MDA) in the serum. Furthermore, there was a significant positive correlation between the serum concentration of BDNF and nitric oxide (NO) in the test group.Using over-the-counter (OTC) medicines which include thiol-group-related agents or any other antioxidants can alleviate oxidative stress and the associated increased inflammation in COVID-19 patients with neurological symptoms.