Neutral sphingomyelinase mediates the co-morbidity trias of alcohol abuse, major depression and bone defects

Relationships among osteoporosis, redox homeostasis, and alcohol addiction: Importance of the brain-bone axis

Overabundance of reactive oxygen species (oxidative distress) leads to redox homeostasis disturbance and is associated with many pathological conditions. Accumulating evidence suggests that oxidative distress may contribute to osteoporosis. This review thoroughly outlines the relationships among osteoporosis, redox homeostasis, and alcohol addiction, since these relations are not sufficiently known and subsequently summarized. The brain-bone axis plays a crucial role in alcohol-induced damage to the nervous and skeletal systems. Alterations in the nervous system can lead to osteoporosis because the central nervous system is involved in bone remodeling through various neural pathways. Conversely, as an endocrine organ, bone secretes a number of bone-derived factors (osteokines), which can influence brain function and behavior. As a result, osteoporosis is more common in individuals with neurological disorders, and sudden neurological events can rapidly increase the risk of osteoporosis. Excessive alcohol consumption is linked to many neurological complications, as well as osteoporosis, which are manifested by disrupted redox homeostasis, inflammation, neurodegeneration, inhibition of neurogenesis, decreased bone mineral density, impaired bone microarchitecture, altered mineral homeostasis, raising fracture risk, hormonal dysregulation, and altered gut microbiota composition. Compared to men, alcohol dependence has more negative consequences for women, including an increased risk of liver, cardiovascular, metabolic, mental disorders, and breast cancer. Abstinence has been demonstrated to improve bone and brain health in alcohol addiction. The discovery of the brain-bone axis may lead to the development of new therapeutic approaches for alcohol and other substance addictions. Further research is needed in this direction, as many questions remain unanswered.

Associations between monocyte to HDL-C ratio and lumbar bone mineral density in alcohol dependent individuals with depression

Osteoporosis, a skeletal disorder that reduces bone density, is a significant health concern. Alcohol dependence, a chronic condition, exacerbates public health problems due to its widespread occurrence and association with various comorbidities, including depression. This study aims to explore the relationship between monocyte to high-density lipoprotein cholesterol ratio (MHR) and lumbar bone mineral density (BMD)in individuals with alcohol dependence and depression. From 2009 to 2018, 49,693 participants were enrolled, and after screening, the study included 2,055 individuals with alcohol-dependency and depression. In this study, multivariate regression analysis was employed to assess the association between monocyte to HDL-C ratio and lumbar bone mineral density. Additionally, we conducted interaction tests and subgroup analysis. The result showed a negative correlation between MHR and lumbar BMD, which remained significant even after adjusting for covariates. Individuals with less than a 9th-grade education showed a positive link with MHR, while those with a college degree or higher had a negative link. This relationship remained significant in the fully adjusted model. A U-shaped relationship between MHR and lumbar BMD was observed in individuals with a high school diploma/GED, after adjusting for various factors. The intricate correlation between MHR and lumbar BMD may suggest the presence of biological interplays and disparities in socioeconomic or behavioral aspects. This underscores the necessity for tailored public health strategies that cater to various educational demographics.

Hepatic sphingomyelin phosphodiesterase 3 promotes steatohepatitis by disrupting membrane sphingolipid metabolism

Metabolic-dysfunction-associated steatohepatitis (MASH) remains a major health challenge. Herein, we identify sphingomyelin phosphodiesterase 3 (SMPD3) as a key driver of hepatic ceramide accumulation through increasing sphingomyelin hydrolysis at the cell membrane. Hepatocyte-specific Smpd3 gene disruption or pharmacological inhibition of SMPD3 alleviates MASH, whereas reintroducing SMPD3 reverses the resolution of MASH. Although healthy livers express low-level SMPD3, lipotoxicity-induced DNA damage suppresses sirtuin 1 (SIRT1), triggering an upregulation of SMPD3 during MASH. This disrupts membrane sphingomyelin-ceramide balance and promotes disease progression by enhancing caveolae-dependent lipid uptake and extracellular vesicle secretion from steatotic hepatocytes to exacerbate inflammation and fibrosis. Consequently, SMPD3 acts as a central hub integrating key MASH hallmarks. Notably, we discovered a bifunctional agent that simultaneously activates SIRT1 and inhibits SMPD3, which shows significant therapeutic potential in MASH treatment. These findings suggest that inhibition of hepatic SMPD3 restores membrane sphingolipid metabolism and holds great promise for developing novel MASH therapies.

Pharmacological and resting state fMRI reveal Osteocalcin's effects on mouse brain regions with high Gpr37 and Gpr158 expression

Osteocalcin (OCN) is an endocrine hormone that signals in the periphery, regulating male fertility, energy expenditure and glucose homeostasis. It can also cross the blood-brain-barrier and act on the brain via receptors GPR37 and GPR158. In the brain, OCN influences neurotransmitter synthesis of serotonin, norepinephrine, and dopamine. OCN's function is related to cognitive and memory performance and lack of OCN is associated with anxiety and depression-like behavior in mice. We used multiparametric magnetic resonance imaging (MRI) including pharmacological MRI and resting state functional MRI, along with gene expression data for Gpr37 and Gpr158 to investigate the physiological effects of intravenously administered OCN on the wild type mouse brain. We found four core brain regions (brainstem, limbic output, association cortex, and basal ganglia) that are highly relevant in all three analytical modalities (i.e. pharmacological, resting state MRI and gene expression) and play therefore a major role in mediating OCN's effect in the brain. This study provides the first imaging data of the physiological impact of OCN on the mouse brain, suggesting its potential role in modulating brain function and its relevance as a candidate for further investigation in anxiety, depression, and cognitive impairments.

Compromising Tyrosine Hydroxylase Function Extends and Blunts the Temporal Profile of Reinforcement by Dopamine Neurons in Drosophila

For a proper representation of the causal structure of the world, it is adaptive to consider both evidence for and evidence against causality. To take punishment as an example, the causality of a stimulus is unlikely if there is a temporal gap before punishment is received, but causality is credible if the stimulus immediately precedes punishment. In contrast, causality can be ruled out if the punishment occurred first. At the behavioral level, this is reflected in the associative principle of timing-dependent valence reversal: aversive memories are formed when a stimulus occurs before the punishment, whereas memories of appetitive valence are formed when a stimulus is presented upon the relieving termination of punishment. We map the temporal profile of memories induced by optogenetic activation of the PPL1-01 neuron in the fly Drosophila melanogaster (of either sex) and find that compromising tyrosine hydroxylase function, either acutely by pharmacological methods or by cell-specific RNAi, extends and blunts this profile. Specifically, it (1) enhances learning with a time gap between the stimulus and PPL1-01 punishment (better trace conditioning), (2) impairs learning when the stimulus immediately precedes PPL1-01 punishment (worse delay conditioning), and (3) prevents learning about a stimulus presented after PPL1-01 punishment has ceased (worse relief conditioning). Under conditions of low dopamine, we furthermore observe a role for serotonin that is pronounced in trace conditioning, weaker in delay conditioning, and absent in relief conditioning. We discuss the psychiatric implications if related alterations in the temporal profile of reinforcement were to occur in humans.

Brain acid sphingomyelinase controls addiction-related behaviours in a sex-specific way

Addiction is a chronic and severe mental disorder with high gender- and sex-specificity. However, the pathogenesis of this disorder is not fully elucidated, and no targeted pharmacotherapy is available. A growing body of evidence points out the potential involvement of the ceramide system in the pathophysiology of addiction. A pathogenic pathway for several mental disorders based on the overexpression of an enzyme involved in ceramide formation, acid sphingomyelinase (ASM), was recently proposed. Here we show a crucial role of ASM specifically overexpressing in the forebrain for various types of addiction-related behaviours in a drug- and sex-specific way. In male mice, a forebrain ASM overexpression led to enhanced alcohol consumption in a free-choice paradigm. It also diminished the reinforcing properties of alcohol and cocaine, but not that of amphetamine, ketamine, or a natural reinforcer fat/carbohydrate-rich food in the conditioned place preference (CPP) test in males. In female mice, a forebrain ASM overexpression enhanced alcohol binge-like drinking, while moderate alcohol consumption was preserved. ASM overexpression in females contributed to CPP establishment for amphetamine, but not for other psychoactive substances. Altogether, this study shows a specific involvement of forebrain ASM in the development of conditioned reinforcing effects of different types of substances with addictive properties in a sex-specific way. Our data enlarge the current knowledge on the specific molecular mechanisms of dependence from various drugs of abuse and might serve as a basis for the development of drug- and sex-specific targeted therapy.

Acid sphingomyelinase activity suggests a new antipsychotic pharmaco-treatment strategy for schizophrenia

Schizophrenia is a chronic and severe mental disorder. It is currently treated with antipsychotic drugs (APD). However, APD's work only in a limited number of patients and may have cognition impairing side effects. A growing body of evidence points out the potential involvement of abnormal sphingolipid metabolism in the pathophysiology of schizophrenia. Here, an analysis of human gene polymorphisms and brain gene expression in schizophrenia patients identified an association of SMPD1 and SMPD3 genes coding for acid- (ASM) and neutral sphingomyelinase-2 (NSM). In a rat model of psychosis using amphetamine hypersensitization, we found a locally restricted increase of ASM activity in the prefrontal cortex (PFC). Short-term haloperidol (HAL) treatment reversed behavioral symptoms and the ASM activity. A sphingolipidomic analysis confirmed an altered ceramide metabolism in the PFC during psychosis. Targeting enhanced ASM activity in a psychotic-like state with the ASM inhibitor KARI201 reversed psychotic like behavior and associated changes in the sphingolipidome. While effective HAL treatment led to locomotor decline and cognitive impairments, KARI201 did not. An RNA sequencing analysis of the PFC suggested a dysregulation of numerous schizophrenia related genes including Olig1, Fgfr1, Gpr17, Gna12, Abca2, Sox1, Dpm2, and Rab2a in the rat model of psychosis. HAL and KARI201 antipsychotic effects were associated with targeting expression of other schizophrenia associated genes like Col6a3, Slc22a8, and Bmal1, or Nr2f6a, respectively, but none affecting expression of sphingolipid regulating genes. Our data provide new insight into a potentially pathogenic mechanism of schizophrenia and suggest a new pharmaco-treatment strategy with reduced side effects.

Trimetazidine Alleviates Bleomycin-Induced Pulmonary Fibrosis by Targeting the Long Noncoding RNA CBR3-AS1-Mediated miRNA-29 and Resistin-Like Molecule alpha 1: Deciphering a Novel Trifecta Role of LncRNA CBR3-AS1/miRNA-29/FIZZ1 Axis in Lung Fibrosis

INTRODUCTION

Pulmonary fibrosis (PF) and tissue remodeling can greatly impair pulmonary function and often lead to fatal outcomes.

METHODOLOGY

In the present study, we explored a novel molecular interplay of long noncoding (Lnc) RNA CBR3-AS1/ miRNA-29/ FIZZ1 axis in moderating the inflammatory processes, immunological responses, and oxidative stress pathways in bleomycin (BLM)-induced lung fibrosis. Furthermore, we investigated the pharmacological potential of Trimetazidine (TMZ) in ameliorating lung fibrosis.

RESULTS

Our results revealed that the BLM-treated group exhibited a significant upregulation in the expression of epigenetic regulators, lncRNA CBR3-AS1 and FIZZ1, compared to the control group (P<0.0001), along with the downregulation of miRNA-29 expression. Furthermore, Correlation analysis showed a significant positive association between lnc CBR3-AS1 and FIZZ1 (R=0.7723, p<0.05) and a significant negative association between miRNA-29 and FIZZ1 (R=-0.7535, p<0.05), suggesting lnc CBR3-AS1 as an epigenetic regulator of FIZZ1 in lung fibrosis. BLM treatment significantly increased the expression of Notch, Jagged1, Smad3, TGFB1, and hydroxyproline. Interestingly, the administration of TMZ demonstrated the ability to attenuate the deterioration effects caused by BLM treatment, as indicated by biochemical and histological analyses. Our investigations revealed that the therapeutic potential of TMZ as an antifibrotic drug could be ascribed to its ability to directly target the epigenetic regulators lncRNA CBR3-AS1/ miRNA-29/ FIZZ1, which in turn resulted in the mitigation of lung fibrosis. Histological and immunohistochemical analyses further validated the potential antifibrotic effects of TMZ by mitigating the structural damage associated with fibrosis.

DISCUSSION

Taken together, our study showed for the first time the interplay between epigenetic lncRNAs CBR3-AS1 and miRNA-29 in lung fibrosis and demonstrated that FIZZ1 could be a downregulatory gene for lncRNA CBR3-AS1 and miRNA-29. Our key findings demonstrate that TMZ significantly reduces the expression of fibrotic, oxidative stress, immunomodulatory, and inflammatory markers, along with epigenetic regulators associated with lung fibrosis. This validates its potential as an effective antifibrotic agent by targeting the CBR3-AS1/miRNA-29/FIZZ1 axis.

Neutral sphingomyelinase controls acute and chronic alcohol effects on brain activity

Alcohol consumption is a widespread phenomenon throughout the world. However, how recreational alcohol use evolves into alcohol use disorder (AUD) remains poorly understood. The Smpd3 gene and its coded protein neutral sphingomyelinase (NSM) are associated with alcohol consumption in humans and alcohol-related behaviors in mice, suggesting a potential role in this transition. Using multiparametric magnetic resonance imaging, we characterized the role of NSM in acute and chronic effects of alcohol on brain anatomy and function in female mice. Chronic voluntary alcohol consumption (16 vol% for at least 6 days) affected brain anatomy in WT mice, reducing regional structure volume predominantly in cortical regions. Attenuated NSM activity prevented these anatomical changes. Functional MRI linked these anatomical adaptations to functional changes: Chronic alcohol consumption in mice significantly modulated resting state functional connectivity (RS FC) in response to an acute ethanol challenge (i.p. bolus of 2 g kg-1) in heterozygous NSM knockout (Fro), but not in WT mice. Acute ethanol administration in alcohol-naïve WT mice significantly decreased RS FC in cortical and brainstem regions, a key finding that was amplified in Fro mice. Regarding direct pharmacological effects, acute ethanol administration increased the regional cerebral blood volume (rCBV) in many brain areas. Here, chronic alcohol consumption otherwise attenuated the acute rCBV response in WT mice but enhanced it in Fro mice. Altogether, these findings suggest a differential role for NSM in acute and chronic functional brain responses to alcohol. Therefore, targeting NSM may be useful in the prevention or treatment of AUD.

Unveiling the multifaceted antiproliferative efficacy of Cichorium endivia root extract by dual modulation of apoptotic and inflammatory genes, inducing cell cycle arrest, and targeting COX-2

Chicory (Cichorium endivia L. divaricatum) is a renowned medicinal plant traditionally used for various ailments, yet the pharmacological potential of its roots, particularly in terms of antitumor activity, remains elusive. In the present study, we explore, for the first time, the metabolomic profile of ethanolic extract from Cichorium endivia roots (CIR) and further unveil its antiproliferative potential. The untargeted phytochemical analysis UPLC/T-TOF-MS/MS identified 131 metabolites in the CIR extract, covering acids, amino acids, flavonoids, alkaloids, nucleotides, and carbohydrates. The antiproliferative activity of the CIR extract was tested in 14 cancer cell lines, revealing significant cytotoxicity (IC50: 2.85-29.15 μg mL-1) and a high selectivity index. Among the cells examined, the CIR extract recorded the most potent antiproliferative activity and selectivity toward HepG2 and Panc-1 cells, with an IC50 of 2.85 μg mL-1 and 3.86 μg mL-1, respectively, and SI > 10. Insights into the mode of action of the antiproliferative activity revealed that CIR extract induces cell arrest in the S phase while diminishing cell distribution in the G0/G1 and G2/M phases in HepG-2 and Panc-1 cells. Flow cytometric and RT-PCR analysis revealed that the CIR extract significantly triggers apoptosis and modulates the expression of pro-apoptotic and anti-apoptotic genes. Furthermore, the CIR extract exhibited a pronounced anti-inflammatory activity, as evidenced by down-regulating key cytokines in LPS-induced RAW 264.7 cells and selectively inhibiting the COX-2 enzyme. Finally, the CIR extract showed a robust total antioxidant capacity, together with potent free radicals and metal scavenging properties, highlighting its role in alleviating oxidative stress. Taken together, this study highlights the multifaceted therapeutic potential of CIR extract as a natural-based antitumor supplement.

Synthesis and antiproliferative evaluation of novel 3,5,8-trisubstituted coumarins against breast cancer

Aim: This study focused on designing and synthesizing novel derivatives of 3,5,8-trisubstituted coumarin. Results: The synthesized compounds, particularly compound 5, exhibited significant cytotoxic effects on MCF-7 cells, surpassing staurosporine, and reduced toxicity toward MCF-10A cells, highlighting potential pharmacological advantages. Further, compound 5 altered the cell cycle and significantly increased apoptosis in MCF-7 cells, involving both early (41.7-fold) and late stages (33-fold), while moderately affecting necrotic signaling. The antitumor activity was linked to a notable reduction (4.78-fold) in topoisomerase IIβ expression. Molecular modeling indicated compound 5's strong affinity for EGFR, human EGF2 and topoisomerase II proteins. Conclusion: These findings highlight compound 5 as a multifaceted antitumor agent for breast cancer.

Serotonin Signaling through Lipid Membranes

Serotonin (5-HT) is a vital modulatory neurotransmitter responsible for regulating most behaviors in the brain. An inefficient 5-HT synaptic function is often linked to various mental disorders. Primarily, membrane proteins controlling the expression and activity of 5-HT synthesis, storage, release, receptor activation, and inactivation are critical to 5-HT signaling in synaptic and extra-synaptic sites. Moreover, these signals represent information transmission across membranes. Although the lipid membrane environment is often viewed as fairly stable, emerging research suggests significant functional lipid-protein interactions with many synaptic 5-HT proteins. These protein-lipid interactions extend to almost all the primary lipid classes that form the plasma membrane. Collectively, these lipid classes and lipid-protein interactions affect 5-HT synaptic efficacy at the synapse. The highly dynamic lipid composition of synaptic membranes suggests that these lipids and their interactions with proteins may contribute to the plasticity of the 5-HT synapse. Therefore, this broader protein-lipid model of the 5-HT synapse necessitates a reconsideration of 5-HT's role in various associated mental disorders.

Masculine depression and its problem behaviors: use alcohol and drugs, work hard, and avoid psychiatry!

The gender role influences vulnerability to mental illness. Substance use, even critical in scale, is perceived as masculine, just like hard (over-)work, while not seeking help. With the ongoing separation between gender and sex, masculine norms become more relevant also to females' mental health. The male depression concept highlights the role of male symptoms in affective disorders. However, the empirical evidence is still limited. Here, we use the denomination 'masculine depression' to open the category for female patients and tested substance use patterns, health services' utilization, and working hours as predictors in a case-control study of 163 depressed in-patients (44% women; masculine vs. non-masculine depression according to a median split of the Male Depression Rating Scale-22) and 176 controls (51% women). We assessed higher depression severity in patients with masculine (vs. non-masculine) depression. Masculine depression (vs. non-masculine depression and vs. no depression) was predicted by more frequent and critical use of alcohol (including binge drinking), tobacco, and illicit drugs, and by longer working times. Moreover, fewer health services contacts due to mental complaints during the previous year were associated with masculine (vs. non-masculine) depression. Alarmingly, even critical substance misuse was not significantly associated with more frequent health services contacts; however, the higher the depression severity, the more contacts the patients reported. Here, we provide evidence that patients with masculine depression are highly burdened and undertreated, which applies equally to female and male patients. This study identified promising targets to establish specialized care offers.

Sex-specific pleiotropic changes in emotional behavior and alcohol consumption in human α-synuclein A53T transgenic mice during early adulthood

Point mutations in the α-synuclein coding gene may lead to the development of Parkinson's disease (PD). PD is often accompanied by other psychiatric conditions, such as anxiety, depression, and drug use disorders, which typically emerge in adulthood. Some of these point mutations, such as SNCA and A30T, have been linked to behavioral effects that are not commonly associated with PD, especially regarding alcohol consumption patterns. In this study, we investigated whether the familial PD point mutation A53T is associated with changes in alcohol consumption behavior and emotional states at ages not yet characterized by α-synuclein accumulation. The affective and alcohol-drinking phenotypes remained unaltered in female PDGF-hA53T-synuclein-transgenic (A53T) mice during both early and late adulthood. Brain region-specific activation of ceramide-producing enzymes, acid sphingomyelinase (ASM), and neutral sphingomyelinase (NSM), known for their neuroprotective properties, was observed during early adulthood but not in late adulthood. In males, the A53T mutation was linked to a reduction in alcohol consumption in both early and late adulthood. However, male A53T mice displayed increased anxiety- and depression-like behaviors during both early and late adulthood. Enhanced ASM activity in the dorsal mesencephalon and ventral hippocampus may potentially contribute to these adverse behavioral effects of the mutation in males during late adulthood. In summary, the A53T gene mutation was associated with diverse changes in emotional states and alcohol consumption behavior long before the onset of PD, and these effects varied by sex. These alterations in behavior may be linked to changes in brain ceramide metabolism.

Psychometric properties of the German Penn Alcohol Craving Scale

Craving for alcohol is an important diagnostic criterion in alcohol use disorder (AUD) and an established predictor of future relapse. The 5-item Penn Alcohol Craving Scale (PACS) is one of the most widely used questionnaires to quantify craving and has been translated into different languages. It is assumed that the PACS constitutes one factor, although theoretical considerations suggest an additional second factor. We conducted stability and factor analyses (principal component and confirmatory factor analyses) of the German PACS (PACS-G) in samples of patients with AUD from the following three German study sites: Erlangen, N = 188 (mean age: 47.1 years, 43.5% female); Mannheim, N = 440 (45.5 years, 28.6% female); Hannover, N = 107 (48.1 years, 48.6% female). In our samples, the 2-factor solution of the PACS-G version is more stable than the internationally assumed 1-factor solution. The resulting two PACS-G subscores 'difficulty to resist' (items 4 and 5) and 'thoughts about alcohol' (items 1, 2, and 3) have an internal consistency (Cronbach's alpha) of 0.80 ≤ α ≤ 0.90, m = 0.86 and 0.86 ≤ α ≤ 0.91, m = 0.89 with an overlap of R2 = 62%. We found good convergent validity assessed via the Craving Automatized Scale-Alcohol and the Obsessive-Compulsive Drinking Scale, but also correlations with depression and anxiety assessed via the Beck's Depression and Anxiety Inventories. This study is the first to provide evidence for a 2-factor solution ('difficulty to resist' and 'thoughts about alcohol') underlying the PACS-G version.

Novel 2-substituted-quinoxaline analogs with potential antiproliferative activity against breast cancer: insights into cell cycle arrest, topoisomerase II, and EGFR activity

Breast cancer is a global health concern, with increasing disease burden and disparities in access to healthcare. Late diagnosis and limited treatment options in underserved areas contribute to poor outcomes. In response to this challenge, we developed a novel family of 2-substituted-quinoxaline analogues, combining coumarin and quinoxaline scaffolds known for their anticancer properties. Through a versatile synthetic approach, we designed, synthesized, and characterized a set of 2-substituted quinoxaline derivatives. The antiproliferative activity of the synthesized compounds was assessed toward the MCF-7 breast cancer cells. Our investigations showed that the synthesized compounds exhibit considerable antiproliferative activity toward MCF-7 cells. Notably, compound 3b, among examined compounds, displayed a superior inhibitory effect (IC50 = 1.85 ± 0.11 μM) toward the growth of MCF-7 cells compared to the conventional anticancer drug staurosporine (IC50 = 6.77 ± 0.41 μM) and showed minimal impact on normal cells (MCF-10A cell lines, IC50 = 33.7 ± 2.04 μM). Mechanistic studies revealed that compound 3b induced cell cycle arrest at the G1 transition and triggered apoptosis in MCF-7 cells, as evidenced by increasing the percentage of cells arrested in the G2/M and pre-G1 phases utilizing flow cytometric analysis and Annexin V-FITC/PI analysis. Moreover, compound 3b was found to substantially suppress topoisomerase enzyme activity in MCF-7 cells. Molecular modeling studies further supported the potential of compound 3b as a therapeutic candidate by demonstrating significant binding affinity to the active sites of both topoisomerase II and EGFR proteins. Taken together, the presented 2-substituted-quinoxaline analogues, especially compound 3b, show promise as potential candidates for the development of effective anti-breast cancer drugs.

Unveiling the interplay between NSAID-induced dysbiosis and autoimmune liver disease in children: insights into the hidden gateway to autism spectrum disorders. Evidence from ex vivo, in vivo, and clinical studies

Autism spectrum disorders (ASD) represent a diverse group of neuropsychiatric conditions, and recent evidence has suggested a connection between ASD and microbial dysbiosis. Immune and gastrointestinal dysfunction are associated with dysbiosis, and there are indications that modulating the microbiota could improve ASD-related behaviors. Additionally, recent findings highlighted the significant impact of microbiota on the development of autoimmune liver diseases, and the occurrence of autoimmune liver disease in children with ASD is noteworthy. In the present study, we conducted both an in vivo study and a clinical study to explore the relationship between indomethacin-induced dysbiosis, autoimmune hepatitis (AIH), and the development of ASD. Our results revealed that indomethacin administration induced intestinal dysbiosis and bacterial translocation, confirmed by microbiological analysis showing positive bacterial translocation in blood cultures. Furthermore, indomethacin administration led to disturbed intestinal permeability, evidenced by the activation of the NLRP3 inflammasomes pathway and elevation of downstream biomarkers (TLR4, IL18, caspase 1). The histological analysis supported these findings, showing widened intestinal tight junctions, decreased mucosal thickness, inflammatory cell infiltrates, and collagen deposition. Additionally, the disturbance of intestinal permeability was associated with immune activation in liver tissue and the development of AIH, as indicated by altered liver function, elevated ASMA and ANA in serum, and histological markers of autoimmune hepatitis. These results indicate that NSAID-induced intestinal dysbiosis and AIH are robust triggers for ASD existence. These findings were further confirmed by conducting a clinical study that involved children with ASD, autoimmune hepatitis (AIH), and a history of NSAID intake. Children exposed to NSAIDs in early life and complicated by dysbiosis and AIH exhibited elevated serum levels of NLRP3, IL18, liver enzymes, ASMA, ANA, JAK1, and IL6. Further, the correlation analysis demonstrated a positive relationship between the measured parameters and the severity of ASD. Our findings suggest a potential link between NSAIDs, dysbiosis-induced AIH, and the development of ASD. The identified markers hold promise as indicators for early diagnosis and prognosis of ASD. This research highlights the importance of maintaining healthy gut microbiota and supports the necessity for further investigation into the role of dysbiosis and AIH in the etiology of ASD.

New ways to cope with depression-study protocol for a randomized controlled mixed methods trial of bouldering psychotherapy (BPT) and mental model therapy (MMT)

BACKGROUND

Due to the growing gap between the demand and supply of therapeutic services for people suffering from depression, with this study, we are investigating the effectiveness and factors of influence of new approaches in group treatments for depression. Two previous studies have already identified bouldering psychotherapy (BPT) as an effective option. It combines psychotherapeutic interventions with action- and body-oriented bouldering exercises. Mental model therapy (MMT) is a new cognitive-behavioral approach for treating depression. It focuses on identifying cognitive distortions, biases in decision making, and false assumptions and aims to correct and replace them with useful mental models. We aim to investigate the effectiveness of the interventions compared with a control group (CG) and to assess the factors of influence in a mixed methods approach.

METHODS

The study is being conducted as a randomized controlled intervention trial. Adult participants with unipolar depression are being randomized into three groups (BPT, MMT, or CG), and the first two groups are undergoing a 10-week treatment phase. CG follows their individual standard treatment as usual. A priori power analysis revealed that about 120 people should be included to capture a moderate effect. The primary outcome of the study is depression rated with the Montgomery and Asberg Depression Rating Scale (MADRS) before (t0), directly after (t1), and 12 months after the intervention phase (t2). Data are being collected via questionnaires, computer-assisted video interviews, and physical examinations. The primary hypotheses will be statistically analyzed by mixed model ANOVAs to compare the three groups over time. For secondary outcomes, further multivariate methods (e.g., mixed model ANOVAs and regression analyses) will be conducted. Qualitative data will be evaluated on the basis of the qualitative thematic analysis.

DISCUSSION

This study is investigating psychological and physical effects of BPT and MMT and its factors of influence on outpatients suffering from depression compared with a CG in a highly naturalistic design. The study could therefore provide insight into the modes of action of group therapy for depression and help to establish new short-term group treatments. Methodological limitations of the study might be the clinical heterogeneity of the sample and confounding effects due to simultaneous individual psychotherapy.

TRIAL REGISTRATION

ISRCTN, ISRCTN12347878. Registered 28 March 2022, https://www.isrctn.com/ISRCTN12347878 .

The dopamine D1 receptor antagonist SCH-23390 blocks the acquisition, but not expression of mitragynine-induced conditioned place preference in rats

Mitragynine (MG) is the primary active constituent of Mitragyna speciosa Korth (kratom), a psychoactive Southeast Asian plant with potential therapeutic use. Numerous studies support roles of dopaminergic system in drug reward. However, the involvement of the dopaminergic system in mediating MG reward and drug-seeking is poorly understood. Using conditioned place preference (CPP) paradigm, the present study aims to evaluate the roles of the dopamine (DA) D1 receptor in the acquisition and expression of MG-induced CPP in rats. The effects of SCH-23390, a selective DA D1 receptor antagonist, on the acquisition of MG-induced CPP were first investigated. Rats were pre-treated systemically with SCH-23390 (0, 0.1 and 0.3 mg/kg, i.p.) prior to MG (10 mg/kg) conditioning sessions. Next, we tested the effects of the DA D1 receptor antagonist on the expression of MG-induced CPP. Furthermore, the effects of a MG-priming dose (5 mg/kg) on the reinstatement of extinguished CPP were tested. The results showed that SCH-23390 dose-dependently suppressed the acquisition of a MG-induced CPP. In contrast, SCH-23390 had no effect on the expression of a MG-induced CPP. The findings of this study suggested a crucial role of the DA D1 receptor in the acquisition, but not the expression of the rewarding effects of MG in a CPP test. Furthermore, blockade of the D1-like receptor during conditioning did not prevent MG priming effects on CPP reinstatement test, suggesting no role for the DA D1 receptor in reinstatement sensitivity.

Self-management with alcohol over lifespan: psychological mechanisms, neurobiological underpinnings, and risk assessment

Self-management includes all behavioural measures and cognitive activities aimed at coping with challenges arising throughout the lifespan. While virtually all of these challenges can be met without pharmacological means, alcohol consumption has long been instrumentalized as a supporting tool to help coping with problems arising selectively at adolescence, adulthood, and ageing. Here, we present, to our knowledge, the first systematic review of alcohol instrumentalization throughout lifespan. We searched MEDLINE, Google Scholar, PsycINFO and CINAHL (from Jan, 1990, to Dec, 2022) and analysed consumption patterns, goals and potential neurobiological mechanisms. Evidence shows a regular non-addictive use of alcohol to self-manage developmental issues during adolescence, adulthood, and ageing. Alcohol is selectively used to overcome problems arising from dysfunctional personality traits, which manifest in adolescence. A large range of psychiatric disorders gives rise to alcohol use for the self-management of distinct symptoms starting mainly in adulthood. We identify those neuropharmacological effects of alcohol that selectively serve self-management under specific conditions. Finally, we discuss the adverse effects and associated risks that arise from the use of alcohol for self-management. Even well-controlled alcohol use adversely impacts health. Based on these findings, we suggest the implementation of an entirely new view. Health policy action may actively embrace both sides of the phenomenon through a personalized informed use that allows for harm-controlled self-management with alcohol.

Behavioural effects of APH199, a selective dopamine D4 receptor agonist, in animal models

RATIONALE

The dopamine D4 receptors (DRD4) play a key role in numerous brain functions and are involved in the pathogenesis of various psychiatric disorders. DRD4 ligands have been shown to moderate anxiety, reward and depression-like behaviours, and cognitive impairments. Despite a series of promising but ambiguous findings, the therapeutic advantages of DRD4 stimulation remain elusive.

OBJECTIVES

The investigation focused on the behavioural effects of the recently developed DRD4 agonist, APH199, to evaluate its impact on anxiety, anhedonia, behavioural despair, establishment and retrieval of alcohol reinforcement, and amphetamine (AMPH)-induced symptoms.

METHODS

Male C57BL/6 J mice and Sprague-Dawley rats were examined in five independent experiments. We assessed APH199 (0.1-5 mg/kg, i.p.) effects on a broad range of behavioural parameters in the open field (OF) test, conditioned place preference test (CPP), elevated plus maze (EPM), light-dark box (LDB), novelty suppressed feeding (NSF), forced swim test (FST), sucrose preference test (SPT), AMPH-induced hyperlocomotion test (AIH), and prepulse inhibition (PPI) of the acoustic startle response in AMPH-sensitized rats.

RESULTS

APH199 caused mild and sporadic anxiolytic and antidepressant effects in EPM and FST, but no remarkable impact on behaviour in other tests in mice. However, we found a significant increase in AMPH-induced hyperactivity, suggesting an exaggeration of the psychotic-like responses in the AMPH-sensitized rats.

CONCLUSIONS

Our data challenged the hypothesis of the therapeutic benefits of DRD4 agonists, pointing out a possible aggravation of psychosis. We suggest a need for further preclinical studies to ensure the safety of antipsychotics with DRD4 stimulating properties.

Characterization of a Neutral Sphingomyelinase Activity in Human Serum and Plasma

Alterations of sphingolipids and their metabolizing enzymes play a role in various diseases. However, peripheral biomarkers for such changes are limited. Particularly, in the increasingly reported involvement of neutral sphingomyelinase (NSM) with four described isoforms in tissues or cells, a peripheral marker is lacking. We here describe the detection of an NSM activity in human serum and plasma samples which hydrolyses fluorescently labeled sphingomyelin to ceramide in a time- and volume-dependent manner. Reaction rates were linear up to 10 days, and serum volumes above 2 vol-% were inhibitory. Biochemical properties were different from acid sphingomyelinase (ASM) with respect to detergent specificity (sodium deoxycholate), pH profile (pH 7-9), and cation dependence: Serum NSM activity was inhibited by EDTA ≥ 1 µM and restored in EDTA-anticoagulated plasma with the addition of ≥ 100 µM Co²⁺. It was independent of Mg²⁺, the typical cofactor of cellular NSM species, and even inhibited by [Mg²⁺] ≥ 20 mM. Serum NSM activity was not correlated with ASM activity and was independent of sex and age in 24 healthy adults. Since human peripheral NSM activity is very low and activities in rodents are even lower or undetectable, future research should aim to increase the reaction rate and determine the source of this enzymatic activity. The established activity could serve as a future biomarker or therapeutic target in diseases affected by sphingolipid derangements.

Adult alcohol drinking and emotional tone are mediated by neutral sphingomyelinase during development in males

Alcohol use, abuse, and addiction, and resulting health hazards are highly sex-dependent with unknown mechanisms. Previously, strong links between the SMPD3 gene and its coded protein neutral sphingomyelinase 2 (NSM) and alcohol abuse, emotional behavior, and bone defects were discovered and multiple mechanisms were identified for females. Here we report strong sex-dimorphisms for central, but not for peripheral mechanisms of NSM action in mouse models. Reduced NSM activity resulted in enhanced alcohol consumption in males, but delayed conditioned rewarding effects. It enhanced the acute dopamine response to alcohol, but decreased monoaminergic systems adaptations to chronic alcohol. Reduced NSM activity increased depression- and anxiety-like behavior, but was not involved in alcohol use for the self-management of the emotional state. Constitutively reduced NSM activity impaired structural development in the brain and enhanced lipidomic sensitivity to chronic alcohol. While the central effects were mostly opposite to NSM function in females, similar roles in bone-mediated osteocalcin release and its effects on alcohol drinking and emotional behavior were observed. These findings support the view that the NSM and multiple downstream mechanism may be a source of the sex-differences in alcohol use and emotional behavior.

Therapeutic potential of bone marrow mesenchymal stem cells in cyclophosphamide-induced infertility

Cancer is a deadly disease characterized by abnormal cell proliferation. Chemotherapy is one technique of cancer treatment. Cyclophosphamide (CYP) is the most powerful chemotherapy medication, yet it has serious adverse effects. It is an antimitotic medicine that regulates cell proliferation and primarily targets quickly dividing cells, and it has been related to varying levels of infertility in humans. In the current study, we assessed the biochemical, histological, and microscopic evaluations of testicular damage following cyclophosphamide administration. Further, we have explored the potential protective impact of mesenchymal stem cell (MSCs) transplantation. The biochemical results revealed that administration of cyclophosphamide increased serum concentrations of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), while it decreased serum concentrations of free testosterone hormone (TH), testicular follicle-stimulating hormone, luteinizing hormone, and free testosterone hormone concentrations, testicular total antioxidant capacity (TAC), and testicular activity of superoxide dismutase (SOD) enzyme. The histology and sperm examinations revealed that cyclophosphamide induced destruction to the architectures of several tissues in the testes, which drastically reduced the Johnsen score as well as the spermatogenesis process. Surprisingly, transplantation of mesenchymal stem cell after cyclophosphamide administration altered the deterioration effect of cyclophosphamide injury on the testicular tissues, as demonstrated by biochemical and histological analysis. Our results indicated alleviation of serum and testicular sex hormones, as well as testicular oxidative stress markers (total antioxidant capacity and superoxide dismutase activity), and nearly restored the normal appearance of the testicular tissues, Johnsen score, and spermatogenesis process. In conclusion, our work emphasizes the protective pharmacological use of mesenchymal stem cell to mitigate the effects of cyclophosphamide on testicular tissues that impair the spermatogenesis process following chemotherapy. These findings indicate that transferring mesenchymal stem cell to chemotherapy patients could significantly improve spermatogenesis.

Stress induces major depressive disorder by a neutral sphingomyelinase 2-mediated accumulation of ceramide-enriched exosomes in the blood plasma

Major depressive disorder (MDD) is a very common, severe disease with a lifetime prevalence of ~ 10%. The pathogenesis of MDD is unknown and, unfortunately, therapy is often insufficient. We have previously reported that ceramide levels are increased in the blood plasma of patients with MDD and in mice with experimental MDD. Here, we demonstrate that ceramide-enriched exosomes in the blood plasma are increased in mice with stress-induced MDD. Genetic studies reveal that neutral sphingomyelinase 2 is required for the formation of ceramide-enriched exosomes in the blood plasma. Accordingly, induced deficiency of neutral sphingomyelinase 2 prevented mice from the development of stress-induced MDD. Intravenous injection of microparticles from mice with MDD or injection of ceramide-loaded exosomes induced MDD-like behavior in untreated mice, which was abrogated by ex vivo pre-incubation of purified exosomes with anti-ceramide antibodies or ceramidase. Mechanistically, injection of exosomes from mice with MDD or injection of ex vivo ceramide-loaded microparticles inhibited phospholipase D (PLD) in endothelial cells in vitro and in the hippocampus in vivo and thereby decreased phosphatidic acid in the hippocampus, which has been previously shown to mediate MDD by plasma ceramide. In summary, our data indicate that ceramide-enriched exosomes are released by neutral sphingomyelinase 2 into the blood plasma upon stress and mediate stress-induced MDD. KEY MESSAGES: Stress induces ceramide-enriched exosomes in the blood plasma. Ceramide-enriched exosomes mediate major depressive disorder (MDD). Deficiency of neutral sphingomyelinase 2 protects from stress-induced MDD. Neutralization or digestion of ceramide in exosomes prevents stress-induced MDD. Ceramide-enriched exosomes inhibit endothelial phospholipase D in the hippocampus.

The system’s genetics of depression and its somatic and mental comorbidities

Depression is a common mood disorder characterised by high comorbidity with other mental and somatic diseases. New studies reveal a shared genetic base for mental core symptoms and somatic comorbidities. Functional analyses showed multiple brain–body pathways involved. This may help considering new therapeutic approaches for depression as a system’s disorder.

Analysis of hyperforin (St. John's wort) action at TRPC6 channel leads to the development of a new class of antidepressant drugs

St. John's wort is an herb, long used in folk medicine for the treatment of mild depression. Its antidepressant constituent, hyperforin, has properties such as chemical instability and induction of drug-drug interactions that preclude its use for individual pharmacotherapies. Here we identify the transient receptor potential canonical 6 channel (TRPC6) as a druggable target to control anxious and depressive behavior and as a requirement for hyperforin antidepressant action. We demonstrate that TRPC6 deficiency in mice not only results in anxious and depressive behavior, but also reduces excitability of hippocampal CA1 pyramidal neurons and dentate gyrus granule cells. Using electrophysiology and targeted mutagenesis, we show that hyperforin activates the channel via a specific binding motif at TRPC6. We performed an analysis of hyperforin action to develop a new antidepressant drug that uses the same TRPC6 target mechanism for its antidepressant action. We synthesized the hyperforin analog Hyp13, which shows similar binding to TRPC6 and recapitulates TRPC6-dependent anxiolytic and antidepressant effects in mice. Hyp13 does not activate pregnan-X-receptor (PXR) and thereby loses the potential to induce drug-drug interactions. This may provide a new approach to develop better treatments for depression, since depression remains one of the most treatment-resistant mental disorders, warranting the development of effective drugs based on naturally occurring compounds.

The effect of mitragynine on extracellular activity of brain dopamine and its metabolites

Kratom, derived from the plant Mitragyna speciosa (M. speciosa) Korth is a traditional psychoactive preparation widely used in Southeast Asia and increasingly in the rest of the world. Use and abuse of Kratom preparations can be attributed to mitragynine (MIT), the main psychoactive compound isolated from its leaves. While MIT may have beneficial effects as a recreational drug, for pain management, and for opiate withdrawal, it may have an addiction potential at higher doses. However, its action in the reward system of the brain is currently unknown. This study investigated how mitragynine (10 mg/kg, i.p.) affects extracellular activity of dopamine (DA) and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the prefrontal cortex (PFC), nucleus accumbens (NAc) and caudate putamen (CPu) of the brain, compared to morphine (MOR; 10 mg/kg, i.p.) and methamphetamine (METH; 10 mg/kg, i.p.). Using in-vivo microdialysis in freely moving rats, we found a significant increase of extracellular DA after MOR and METH, but not after MIT in all three brain regions. MIT led to a significant increase of DOPAC and/or HVA in these brain regions while MOR and METH had only moderate effects. These findings suggest a strong and prolonged effect of MIT on DA synthesis/metabolism, but not on extracellular DA activity, which may limit the addiction risk of MIT, in contrast to MOR and METH.