Depression in adolescence is influenced by the environment, family members, social relationships, and genetic factors. Gene polymorphisms of serotonin receptors were associated with mental/psychiatric disorders, including impulsive, aggressive, violent, antisocial or criminal conduct, schizophrenia, eating disorders, alexithymia, autism, and major depressive disorder (MDD). Few studies reported the association between serotonin receptor polymorphisms and depressive symptoms in nonclinical subjects. The present study aimed to evaluate the serotonin receptor polymorphisms in nonclinical adolescents presenting depressive symptoms. The results clearly demonstrated that nonclinical adolescents with severe depressive symptoms had a high concentration of GA + AA in the recessive model and of AA in the homozygous model of the rs6311 polymorphism. The data indicated that the A allele was associated with severe depressive symptoms. Moreover, the analysis highlighted a trend of association of TT + CT in the recessive model for rs6313 polymorphism and severe symptoms. In conclusion, our study confirms that the A allele for rs6311 represents a risk factor, and the allele T for rs6313 could be a possible risk factor for severe depressive symptoms. As a consequence, the allele G for rs6311 and the allele C for rs6313 could be protective against severe depressive symptoms. Therefore, it might be appropriate to work preventively on adolescents with the A allele for rs6311 and T allele for rs6313 polymorphism to reduce the possibility of developing depressive symptoms and to preserve mental health in young people.

Maladaptive Daydreaming (MD) is an excessive absorption in vivid fantasies interfering with individuals' daily functioning, which has been associated with adverse psychological outcomes and adult attachment insecurities. However, no study to date has addressed the relationships between MD, parental care, unresolved attachment, and psychological symptoms (depression/anxiety and obsessive-compulsive disorder; OCD) in a sample of young adults. In this study, 1295 young adults (401 males) completed an online survey including the Parental Bonding Instrument, Maladaptive Daydreaming Scale, Adult Unresolved Attachment Questionnaire, and the DSM-5 Level 1 Cross-Cutting Symptom Measure. The results evidenced the differential contribution of maternal and paternal care on individuals' psychological symptoms; whilst higher maternal care was negatively related to OCD symptoms, higher paternal care was negatively linked to depression/anxiety symptoms. A relationship between unresolved attachment, MD and psychopathological symptoms emerged; specifically, MD mediated the relationships between unresolved attachment and depression/anxiety and OCD symptoms. Overall, paternal and maternal care may have distinct roles in predicting individuals' psychopathological outcomes. In the presence of unresolved attachment, MD may represent a dissociative response that allows individuals to deal with negative experiences through psychopathological symptoms. Understanding the specific pathways that lead to different psychopathological outcomes could have important implications in developing preventive clinical interventions.

Background: Persistent alterations in taste and smell affect a significant proportion of individuals following COVID-19, representing a component of post-acute COVID-19 syndrome, commonly referred to as long COVID. The degradation of sphingomyelin by acid sphingomyelinase is regarded as a biomarker for acquired demyelinating neuropathies. Objectives: This study was aimed to enroll women who contracted COVID-19 during pregnancy and experienced persistent alterations in taste and/or smell for more than 1 year post-infection, in comparison to pregnant women without any disturbances in these senses. Methods: The patients were subjected to a questionnaire investigating smell and taste disorders more than 1 year after the infection. Then, the levels of acid sphingomyelinase in the plasma of the participants were assessed. Results: The results showed that in women who had been pregnant and who had been infected with SARS Cov-2 during the COVID period and who still had taste and smell disorders 1 year later, plasma acid sphingomyelinase levels were double that of pregnant women who had contracted the infection during the COVID period but had not reported taste and smell disorders and that of pregnant women analyzed after the COVID period. Conclusions: The results suggest a hypothesis that the persistence of sensory disturbances in long COVID was probably due to a failure to utilize brain circuitry with demyelination resulting from chemosensory dysfunction of the olfactory epithelium.

Several single nucleotide polymorphisms (SNPs) of the vitamin D receptor (VDR) have been observed in association with susceptibility to various pathologies, including autism, major depression, age-related changes in cognitive functioning, and Parkinson’s and Alzheimer’s diseases. This study aimed to establish the association between Fok1/Apa1 polymorphic variants and anxious/depressive symptoms in nonclinical adolescents from central Italy, with the goal of identifying the risk of developing both symptoms. We found no significant difference in genotype distribution or dominant/recessive models of Fok1/Apa1 VDR polymorphic variants between subjects with anxious/depressive symptoms and controls. HN9.10e cell lines carrying the AA genotype for Fok1 and the CC genotype for Apa1 responded better to treatment with vitamin D3 than cell lines carrying the AG genotype for Fok1 and CA genotype for Apa1. Cell lines carrying the GG genotype for Fok1 and the AA genotype for Apa1 did not respond at all, suggesting avenues for future studies in both the general population and individuals with mental and/or neuropsychiatric disorders. These studies suggest that the level of response to vitamin D3 administered to prevent and/or treat mental or neurological disorders could depend on the polymorphic variants of the vitamin D receptor.