Changes in Cortisol and in Oxidative/Nitrosative Stress Indicators after ADHD Treatment

Abstract

Although ADHD is one of the most prevalent diseases during childhood, we still do not know its precise origin; oxidative/nitrosative stress and the hypothalamic–pituitary–adrenal axis are suggested contributors. Methylphenidate, among others, is the main drug used in ADHD patients, but its effects on relevant markers and structures remain unclear. This study, involving 59 patients diagnosed with ADHD according to DSM-5 criteria, aimed to assess changes in cortisol levels (using cortisol awakening response, CAR) and oxidative/nitrosative status with the treatment. Blood samples before and 3 months after treatment with methylphenidate were used to measure oxidative and inflammatory markers, as well as the endogenous antioxidant activity, while saliva samples tracked cortisol awakening response (CAR). The results showed a treatment-related improvement in the redox profile, with the reduction in advanced oxidation protein products (AOPP), lipid peroxidation (LPO), and nitrite plus nitrate (NOx) levels, and the increase in the enzymatic activities of glutathione reductase (GRd) and catalase (CAT). Moreover, the area under the curve (AUC) of CAR increased significantly, indicating increased reactivity of the HPA axis. These results support, for the first time, the involvement of the endogenous antioxidant system in the pathophysiology of ADHD.

Differences in the Interleukins profile in Inatentive-ADHD prepubertal children are probably related to comorbidities

“…In a group of patients of both sexes aged between 6 and 14 years, MPH treatment induced an improvement in the redox status, in ammatory pro le, and response of the HPA axis [29]. In addition, MPH treatment it´s associated with modi cations in other ways of tryptophan metabolism: a) the indole tryptphan metabolites showed changes that are also related to the presence of DS [49], and b) serotonin and melatonin showed subtle favourable changes in both serum concentrations and daily uctuations [50].…”

“…Cytokines play an important role in neurodevelopmental processes, affecting glial cell development and neural and synaptic maturation [26]. Subclinical neuroin ammation has been demonstrated in ADHD [27], with increased oxidative stress in animals [28] and in paediatric patients [29]. A correlation has been detected between elevated levels of proin ammatory cytokines and the severity of symptoms in children with ADHD [30,31], which is absent in adult patients with ADHD [32].…”