Imbalances in dopamine activity significantly contribute to the pathophysiology of several neuropsychiatric disorders, including addiction, ADHD, schizophrenia, impulse control disorders, and Parkinson\'s Disease. Neuro(active)steroids, comprising endogenous steroids that finely modulate neuronal activity, are considered crucial regulators of brain function and behavior, with implications in various physiological processes and pathological conditions. Specifically, subclasses of Neuro(active)steroids belonging to the 5α reductase pathway are prominently involved in brain disorders characterized by dopaminergic signaling imbalances. This review highlights the neuromodulatory effects of Neuro(active)steroids on the dopamine system and related aberrant behavioral phenotypes. We critically appraise the role of pregnenolone, progesterone, and allopregnanolone on dopamine signaling. Additionally, we discuss the impact of pharmacological interventions targeting 5α reductase activity in neuropsychiatric conditions characterized by excessive activation of the dopaminergic system, ranging from psychotic (endo)phenotypes and motor complications to decision-making problems and addiction.

OBJECTIVE: Neurosteroids are allosteric modulators of GABAA currents, acting through several functional binding sites although their affinity and specificity for each site are unknown. The goal of this study was to measure steady-state binding affinities of various neurosteroids for specific sites on the GABAA receptor.
METHODS: Two methods were developed to measure neurosteroid binding affinity: (1) quenching of specific tryptophan residues in neurosteroid binding sites by the neurosteroid 17-methylketone group, and (2) FRET between MQ290 (an intrinsically fluorescent neurosteroid) and tryptophan residues in the binding sites. The assays were developed using ELIC-α1GABAAR, a chimeric receptor containing transmembrane domains of the α1-GABAA receptor. Tryptophan mutagenesis was used to identify specific interactions.
RESULTS: Allopregnanolone (3α-OH neurosteroid) was shown to bind at intersubunit and intrasubunit sites with equal affinity, whereas epi-allopregnanolone (3β-OH neurosteroid) binds at the intrasubunit site. MQ290 formed a strong FRET pair with W246, acting as a site-specific probe for the intersubunit site. The affinity and site-specificity of several neurosteroid agonists and inverse agonists was measured using the MQ290 binding assay. The FRET assay distinguishes between competitive and allosteric inhibition of MQ290 binding and demonstrated an allosteric interaction between the two neurosteroid binding sites.
CONCLUSIONS: The affinity and specificity of neurosteroid binding to two sites in the ELIC-α1GABAAR were directly measured and an allosteric interaction between the sites was revealed. Adaptation of the MQ290 FRET assay to a plate-reader format will enable screening for high affinity agonists and antagonists for neurosteroid binding sites.

Dopaminergic neurons express a heteromer composed of the dopamine D3 receptor and the α4β2 nicotinic acetylcholine receptor, the D3R-nAChR heteromer, activated by both nicotine and dopamine D2 and D3 receptors agonists, such as quinpirole, and crucial for dopaminergic neuron homeostasis. We now report that D3R-nAChR heteromer activity is potentiated by 17-β-estradiol which acts as a positive allosteric modulator by binding a specific domain on the α4 subunit of the nicotinic receptor protomer. In mouse dopaminergic neurons, in fact, 17-β-estradiol significantly increased the ability of nicotine and quinpirole in promoting neuron dendritic remodeling and in protecting neurons against the accumulation of α-synuclein induced by deprivation of glucose, with a mechanism that does not involve the classical estrogen receptors. The potentiation induced by 17-β-estradiol required the D3R-nAChR heteromer since either nicotinic receptor or dopamine D3 receptor antagonists and interfering TAT-peptides, but not the estrogen receptor antagonist fulvestrant, specifically prevented 17-β-estradiol effects. Evidence of estrogens neuroprotection, mainly mediated by genomic mechanisms, have been provided, which is in line with epidemiological data reporting that females are less likely to develop Parkinson\'s Disease than males. Therefore, potentiation of D3R-nAChR heteromer activity may represent a further mechanism by which 17-β-estradiol reduces dopaminergic neuron vulnerability.

UNASSIGNED: Newly diagnosed people with multiple sclerosis frequently report fatigue, pain, depression and anxiety. Preventative programmes may be beneficial, but there is limited evidence of their effectiveness, especially long-term follow-up.
UNASSIGNED: The programme consisted of 6-month face to face intervention (an introductory workshop, psychology-led group sessions and individual physical therapy) followed by 6-month self-guided therapy. Outcome measures were taken at baseline, 6 and 12 months. Primary outcomes measures were self-report questionnaires for fatigue, satisfaction with life and disease acceptance. Secondary outcomes were spirometry, spiroergometric parameters and neuroactive steroid levels.
UNASSIGNED: From 22 participants enrolled, 17 completed the first 6 months and 13 the follow-up. Fatigue measured on the Fatigue scale for motor and cognitive functions decreased significantly at 6 months (p = 0.035) and at follow-up (p = 0.007). The Modified Fatigue Impact Scale (p = 0.035) and Satisfaction With Life Scale (p = 0.007) significantly increased at follow-up. Spirometry, spiroergometric parameters, steroid hormones and neuroactive steroids levels did not change significantly.
UNASSIGNED: This programme reduces fatigue and improves satisfaction with life in this patient group with improvements sustained at 12 months. People who participated more frequently showed greater benefit.
UNASSIGNED: The paper describes the effects of a complex preventative intervention for people with newly diagnosed Multiple Sclerosis. The study found that this programme reduces fatigue and improves satisfaction with life with long-term benefit (at 12-month follow up). The individuals who participated less frequently experienced fewer benefits.

Neuroactive steroids are a group of steroid molecules that are involved in the regulation of functions of the nervous system. The nervous system is not only the site of their action, but their biosynthesis can also occur there. Neuroactive steroid levels depend not only on the physiological state of an individual (person\'s sex, age, diurnal variation, etc.), but they are also affected by various pathological processes in the nervous system (some neurological and psychiatric diseases or injuries), and new knowledge can be gained by monitoring these processes. The aim of our research was to develop and validate a comprehensive method for the simultaneous determination of selected steroids with neuroactive effects in human serum. The developed method enables high throughput and a sensitive quantitative analysis of nine neuroactive steroid substances (pregnenolone, progesterone, 5α-dihydroprogesterone, allopregnanolone, testosterone, 5α-dihydrotestosterone, androstenedione, dehydroepiandrosterone, and epiandrosterone) in 150 μL of human serum by ultrahigh-performance liquid chromatography with tandem mass spectrometry. The correlation coefficients above 0.999 indicated that the developed analytical procedure was linear in the range of 0.90 nmol/L to 28.46 μmol/L in human serum. The accuracy and precision of the method for all analytes ranged from 83 to 118% and from 0.9 to 14.1%, respectively. This described method could contribute to a deeper understanding of the pathophysiology of various diseases. Similarly, it can also be helpful in the search for new biomarkers and diagnostic options or therapeutic approaches.

Activation of the GABAA receptor is associated with numerous behavioral end points ranging from anxiolysis to deep anesthesia. The specific behavioral effect of a GABAergic compound is considered to correlate with the degree of its functional effect on the receptor. Here, we tested the hypothesis that a low-efficacy allosteric potentiator of the GABAA receptor may act, due to a ceiling effect, as a sedative with reduced and limited action. We synthesized a derivative, named (3α,5β)-20-methyl-pregnane-3,20-diol (KK-235), of the GABAergic neurosteroid 5β-pregnane-3α,20α-diol. Using electrophysiology, we showed that KK-235 is a low-efficacy potentiator of the synaptic-type α1β2γ2L GABAA receptor. In the zebrafish larvae behavioral assay, KK-235 was found to only partially block the inverted photomotor response (PMR) and to weakly reduce swimming behavior, whereas the high-efficacy GABAergic steroid (3α,5α,17β)-3-hydroxyandrostane-17-carbonitrile (ACN) fully blocked PMR and spontaneous swimming. Coapplication of KK-235 reduced the potentiating effect of ACN in an electrophysiological assay and dampened its sedative effect in behavioral experiments. We propose that low-efficacy GABAergic potentiators may be useful as sedatives with limited action.

Steroid hormones have diverse roles in pregnancy; some help stabilise pregnancy and influence the stability of pregnancy and the onset of labour. Changes and disorders in steroidogenesis may be involved in several pregnancy pathologies. To date, only a few studies have performed a very limited steroid analysis in multiple pregnancies. Our teams investigated multiple pregnancies regarding the biosynthesis, transport, and effects of steroids. We recruited two groups of patients: pregnant women with multiple pregnancies as the study group, and a control singleton pregnancies group. Blood samples were drawn from the participants and analysed. Information about the mother, foetus, delivery, and newborn was extracted from medical records. The data were then analysed. The gestational age of twin pregnancies during delivery ranged from 35 + 3 to 39 + 3 weeks, while it was 38 + 1 to 41 + 1 weeks for the controls. Our findings provide answers to questions regarding the steroidome in multiple pregnancies. Results demonstrate differences in the steroidome between singleton and twin pregnancies. These were based on the presence of two placentae and two foetal adrenal glands, both with separate enzymatic activity. Since every newborn was delivered by caesarean section, analysis was not negatively influenced by changes in the steroid metabolome associated with the spontaneous onset of labour.

Endogenous neurosteroids (NS) and their synthetic analogs, neuroactive steroids (NAS), are potentially useful drug-like compounds affecting the pathophysiology of miscellaneous central nervous system disorders (e.g. Alzheimer´s disease, epilepsy, depression, etc.). Additionally, NS have been shown to promote neuron viability and neurite outgrowth upon injury. The molecular, structural and physicochemical basis of the NS effect on neurons is so far not fully understood, and the development of new, biologically relevant assays is essential for their comparative analysis and for assessment of their mechanism of action. Here, we report the development of a novel, plate-based, high-content in vitro assay for screening of NS and newly synthesized, 5β-reduced NAS for the promotion of postnatal neuron survival and neurite growth using fluorescent, postnatal mixed cortical neuron cultures isolated from thy1-YFP transgenic mice. The screen allows a detailed time course analysis of different parameters, such as the number of neurons or neurite lengths of 7-day, in vitro neuron cultures. Using the screen, we identify a new NAS, compound 42, that promotes the survival and growth of postnatal neurons significantly better than several endogenous NS (dehydroepiandrosterone, progesterone, and allopregnanolone). Interestingly, we demonstrate that compound 42 also promotes the proliferation of glia (in particular oligodendrocytes) and that the glial function is critical for its neuron growth support. Computational analysis of the biological data and calculated physicochemical properties of tested NS and NAS demonstrated that their biological activity is proportional to their lipophilicity. Together, the screen proves useful for the selection of neuron-active NAS and the comparative evaluation of their biologically relevant structural and physicochemical features.

The greater prevalence and incidence of Parkinson\'s disease (PD) in men suggest a beneficial effect of sex hormones. Neuroactive steroids have neuroprotective activities thus offering interesting option for disease-modifying therapy for PD. Neuroactive steroids are also neuromodulators of neurotransmitter systems and may thus help to control PD symptoms and side effect of dopamine medication. Here, we review the effect on sex hormones (estrogen, androgen, progesterone and its metabolites) as well as androstenediol, pregnenolone and dehydroepiandrosterone) in human studies and in animal models of PD. The effect of neuroactive steroids is reviewed by considering sex and hormonal status to help identify specifically for women and men with PD what might be a preventive approach or a symptomatic treatment. PD is a complex disease and the pathogenesis likely involves multiple cellular processes. Thus it might be useful to target different cellular mechanisms that contribute to neuronal loss and neuroactive steroids provide therapeutics options as they have multiple mechanisms of action.

Post-finasteride syndrome and post-SSRI sexual dysfunction, are two poorly explored clinical conditions in which men treated for androgenetic alopecia with finasteride or for depression with SSRI antidepressants show persistent side effects despite drug suspension (e.g., sexual dysfunction, psychological complaints, sleep disorders). Because of some similarities in the symptoms, common pathological mechanisms are proposed here. Indeed, as discussed, clinical studies and preclinical data obtained so far suggest an important role for brain modulators (i.e., neuroactive steroids), neurotransmitters (i.e., serotonin, and cathecolamines), and gut microbiota in the context of the gut-brain axis. In particular, the observed interconnections of these signals in these two clinical conditions may suggest similar etiopathogenetic mechanisms, such as the involvement of the enzyme converting norepinephrine into epinephrine (i.e., phenylethanolamine N-methyltransferase). However, despite the current efforts, more work is still needed to advance the understanding of these clinical conditions in terms of diagnostic markers and therapeutic strategies.