Dear colleagues,
It is my great pleasure to introduce to you the third issue of 2020 featuring original research on attention-deficit/hyperactivity disorder and eating disorders.
Korman and colleagues review the evidence for the circadian clock genes, chronotherapy and sleep and circadian rhythm dysfunction in attention-deficit/hyperactivity disorder (ADHD). Single nucleotide polymorphisms in the circadian genes have been associated with core symptoms of ADHD, increased evening-orientation and sleep disturbances. Furthermore, bright light therapy was shown to be effective in re-alignment of circadian physiology as well as overall improvement of symptoms of ADHD.
Müller et al. investigated the electrophysiological characteristics of ADHD while using neuroalgorithms for the optimal separation of patients with ADHD from healthy subjects. The authors claim that patients and healthy controls can be classified with a sensitivity ranging from 75% to 83% with specificity of 71–77%. The usefulness of neuroalgorithms may improve the diagnostic process by making it less subjective and more reliable while linking it to underlying pathology.
Königschulte and associates examined the effects of acute phenylalanine tyrosine depletion (APTD) and acute tryptophan depletion (ATD) on bimodal divided attention. Significant differences in the mean reaction time were detected towards auditory stimuli but not towards visual stimuli. The results indicate a potential dissociation between decreased brain 5-HT and DA synthesis on the bimodal divided attention task performance.
Haleem and colleagues investigated circulating cortisol and leptin in depression associated with anorexia or obesity. There were significantly more depressed patients who were obese, as well as depressed males that were underweight. A BMI related increase in serum leptin levels and a decrease in serum cortisol levels were found for both genders. Depression in underweight BMI groups was associated with a decrease in serum leptin and an increase in cortisol.
Roczniak and associates assessed the serum interleukin 15 (IL-15) levels in anorexia nervosa (AN) female adolescents and compared it to obese and normal weight female adolescents. IL-15 levels were higher in the AN group compared to the control group but lower compared to the obese group. Further research is needed as the role of IL-15 in the pathogeneis of AN and obesity remains elusive.
Paszynska and colleagues compared opiorphin levels in saliva of patients with anorexia nervosa to healthy subjects. No difference was detected in salivary opiorphin levels between groups. The authors conclude that the salivary opiorphin levels are not useful as a marker of anorexia nervosa.
Paszynska et al. explored the association between opiorphin and stress/immune biomarkers and cortisol in patients with restrictive-type AN. AN patients had increased cortisol and secretory immunoglobulin A levels. No association was found between opiorphin and other markers. The authors conclude that effects of stress responses can be reliably assessed in the saliva of AN patients.
In a brief report, Pan et al. highlight the challenges and the effect of sample handling on inflammatory cytokines in serum. Cytokine levels and pre-processing times differed by recruitment site, and delays in pre-processing times was associated with increased cytokine concentrations. This highlights the need for careful evaluation of sample collection and handling methods when designing biomarker studies.
Yours sincerely,