Exercise Regulates Peripheral Blood Serotonin to Improve the Addiction and Impulse of Methamphetamine Withdrawal Patients

Background: This study aimed to explore the effect of aerobic combined with resistance exercise on the level of 5-HT in the peripheral blood of methamphetamine (METH) withdrawal patients, improving cue-induced craving and impulse. Methods： Fifty methamphetamine withdrawal patients were included. The patients underwent eight weeks of aerobic combined with resistance exercise. The sessions lasted an hour and were conducted five times a week. Impulsivity (BIS-11), craving (VAS craving), and control (VAS control) were assessed before and after the intervention. ELISA was used to detect peripheral blood 5-HT levels. Results： The results showed that peripheral blood 5-HT and VAS control significantly increased after the exercise. In contrast, VAS craving and BIS-11 significantly decreased after the exercise. Conclusions： We present that eight weeks of aerobic combined with resistance exercise can alter the peripheral blood 5-HT levels of METH withdrawal patients and improve the cue-induced craving and impulse levels.

Serotonin variations and sleep disorders among shift workers. A cross-sectional study

Sleep disorders are prevalent occupational health problems among shift workers, especially healthcare workers with long shifts. Serotonin is a neurotransmitter related to circadian variations accompanied by shift work. A cross-sectional study was performed on 73 nurses at a tertiary hospital in Cairo, Egypt, to assess sleep quality among shift work nurses (SWNs), to determine blood serotonin level, and its relation to shift work and sleep quality. A demographic and occupational history questionnaire, Pittsburgh Sleep Quality Index (PSQI) questionnaire, and measurement of blood serotonin were carried out to the studied group. The data were analyzed using SPSS 25, and descriptive statistics, unpaired t-test, ANOVA, Kruskal–Wallis Test, Chi-square, Spearman correlation, and multivariate regression analysis were utilized. The results showed that the mean PSQI global score was significantly higher among SWNs than non-shift work nurses (NSWNs) and was the highest (10.32 ± 3.56 and 10.22 ± 2.4, respectively) among rotatory and fixed night shift nurses. Blood serotonin showed highly significant differences between SWNs over NSWNs ( p = 0.001), and mostly reduced among rotatory and fixed night shift nurses (66.7% and 65%, respectively). Moreover, there were highly significant differences in serotonin levels between poor and good sleep quality nurses ( p < 0.001), and most of the poor sleep quality nurses (62.7%) had low serotonin levels. Abnormal serotonin level (odds = 246.5) and working years (odds = 1.2) were statistically significant predictors of poor sleep quality. In conclusion, SWNs, especially rotating and night shift nurses, suffer from poor sleep quality associated with abnormal levels of blood serotonin.

Central Serous Chorioretinopathy and Blood Serotonin Concentrations

Background: To investigate blood serotonin (5-hydroxytryptamine (5-HT)) concentrations and their relationships with selected characteristics in patients with central serous chorioretinopathy (CSC). Methods: This was a prospective study including 93 patients with active CSC. Blood concentrations of 5-HT, adrenocorticotropic hormone, and cortisol were measured in patients with CSC. Selected patient characteristics, including disease history (acute or chronic), medication use, smoking history, mood status, best-corrected visual acuity (BCVA), subfoveal choroidal thickness (SCT), findings on fluorescein and indocyanine green angiography, and anatomical changes were evaluated during follow-up. Results: Eleven of the 93 patients had low 5-HT concentrations (<57 ng/mL) (12%, eight men and three women; mean age 55 years); we identified no significant relationship with acute/chronic disease status. The patients with low 5-HT were significantly more likely to have five or more fluorescein leakage sites (p = 0.0275), recurrence of subretinal fluids (p < 0.0001), and failure to achieve significant improvement in BCVA during follow-up (p = 0.862) than patients with 5-HT within the normal range. Conclusions: Blood serotonin concentrations may influence the pathophysiology and prognosis of CSC.

Decreased phenol sulfotransferase activities associated with hyperserotonemia in autism spectrum disorders

Hyperserotonemia is the most replicated biochemical abnormality associated with autism spectrum disorders (ASD). However, previous studies of serotonin synthesis, catabolism, and transport have not elucidated the mechanisms underlying this hyperserotonemia. Here we investigated serotonin sulfation by phenol sulfotransferases (PST) in blood samples from 97 individuals with ASD and their first-degree relatives (138 parents and 56 siblings), compared with 106 controls. We report a deficient activity of both PST isoforms (M and P) in platelets from individuals with ASD (35% and 78% of patients, respectively), confirmed in autoptic tissues (9 pineal gland samples from individuals with ASD—an important source of serotonin). Platelet PST-M deficiency was strongly associated with hyperserotonemia in individuals with ASD. We then explore genetic or pharmacologic modulation of PST activities in mice: variations of PST activities were associated with marked variations of blood serotonin, demonstrating the influence of the sulfation pathway on serotonemia. We also conducted in 1645 individuals an extensive study of SULT1A genes, encoding PST and mapping at highly polymorphic 16p11.2 locus, which did not reveal an association between copy number or single nucleotide variations and PST activity, blood serotonin or the risk of ASD. In contrast, our broader assessment of sulfation metabolism in ASD showed impairments of other sulfation-related markers, including inorganic sulfate, heparan-sulfate, and heparin sulfate-sulfotransferase. Our study proposes for the first time a compelling mechanism for hyperserotonemia, in a context of global impairment of sulfation metabolism in ASD.

Functional polymorphism of the serotonin reuptake transporter SLC6A4 gene in various clinical variants of irritable bowel syndrome

Rationale: Irritable bowel syndrome (IBS) is a multifactorial disease, the genetic aspect of which is being actively studied.Aim: To investigate functional polymorphism of the serotonin reuptake transporter (SERT) SLC6A4 gene of various clinical variants of IBS.Materials and methods: We performed a cross-sectional single center study in 79 Caucasian patients with IBS (according to the Rome criteria IV). The patients were divided into two groups: group 1, IBS with diarrhea (IBS-D, n = 45) and group 2, IBS with constipation (IBS-C, n = 34). The control group included 59 Caucasian patients with gastrointestinal disorders without IBS. Polymorphism 5-HTTLPR of the SLC6A4 gene was assessed in all subjects. In group 1 patients, blood serotonin levels were measured and psychological tests were performed, including Spielberger's State / Trait Anxiety Inventory, quality of life by SF36 and GSRS, Asthenia scale, VAS scores for pain intensity.Results: Thirty-five of 45 (77.8%) patients with IBS-D carried the mutant S allele, which was significantly more frequent than in the IBS-C group (p = 0.002) and in the control group (p = 0.005). There were no statistically significant differences (p = 0.54) in the frequency of detection of the homozygous LL genotype (normal allele) and the heteroand homozygous mutant alleles (SL and SS) genotype between the IBS-C and control patients. In the IBS-D group, a gender difference for the mutant SS allele of 5-HTTLPR was found, with significantly higher frequency in female patients (p = 0.0147). No significant gender differences in the genotype distribution between the patients with IBS-C and the control group were found. There were also no differences in blood serotonin levels in the IBS patients with various 5-HTTLPR types (p = 0.086); they were all in the reference range. However, there was a trend towards lower serotonin levels in the LL genotype carriers compared to those with the SS/SL polymorphisms. The Gastroenterological inventory GSRS demonstrated significantly higher total score for the constipation syndrome in the patients with homozygous LL 5-HTTLPR polymorphism, compared to that in the patients with the SS/SL genotype (p = 0.013).Conclusion: The results may be related to lower expression of the SLC6A4 gene in the carriers of the mutant allele in the 5-HTTLPR promoter and subsequent decreased rate of serotonin uptake, with resulting stimulation of the gastrointestinal tract. The SERT polymorphism of the SLC6A4 gene is worth further investigation as a potential candidate gene in the IBS pathophysiology.