Oxytocin-induced increases in cytokines and clinical effect on the core social features of autism: Analyses of RCT datasets.

Although oxytocin may provide a novel therapeutics for the core features of autism spectrum disorder (ASD), previous results regarding the efficacy of repeated or higher dose oxytocin are controversial, and the underlying mechanisms remain unclear. The current study is aimed to clarify whether repeated oxytocin alter plasma cytokine levels in relation to clinical changes of autism social core feature. Here we analyzed cytokine concentrations using comprehensive proteomics of plasmas of 207 adult males with high-functioning ASD collected from two independent multi-center large-scale randomized controlled trials (RCTs): Testing effects of 4-week intranasal administrations of TTA-121 (A novel oxytocin spray with enhanced bioavailability: 3U, 6U, 10U, or 20U/day) and placebo in the crossover discovery RCT; 48U/day Syntocinon or placebo in the parallel-group verification RCT. Among the successfully quantified 17 cytokines, 4 weeks TTA-121 6U (the peak dose for clinical effects) significantly elevated IL-7 (9.74, 95 % confidence interval [CI] 3.59 to 15.90, False discovery rate corrected P (PFDR) < 0.001), IL-9 (56.64, 20.46 to 92.82, PFDR < 0.001) and MIP-1b (18.27, 4.96 to 31.57, PFDR < 0.001) compared with placebo. Inverted U-shape dose-response relationships peaking at TTA-121 6U were consistently observed for all these cytokines (IL-7: P < 0.001; IL-9: P < 0.001; MIP-1b: P = 0.002). Increased IL-7 and IL-9 in participants with ASD after 4 weeks TTA-121 6U administration compared with placebo was verified in the confirmatory analyses in the dataset before crossover (PFDR < 0.001). Furthermore, the changes in all these cytokines during 4 weeks of TTA-121 10U administration revealed associations with changes in reciprocity score, the original primary outcome, observed during the same period (IL-7: Coefficient = -0.05, -0.10 to 0.003, P = 0.067; IL-9: -0.01, -0.02 to -0.003, P = 0.005; MIP-1b: -0.02, -0.04 to -0.007, P = 0.005). These findings provide the first evidence for a role of interaction between oxytocin and neuroinflammation in the change of ASD core social features, and support the potential role of this interaction as a novel therapeutic seed. Trial registration: UMIN000015264, NCT03466671/UMIN000031412.

Effect of chlorpyrifos-exposure on the expression levels of CYP genes in Daphnia magna and examination of a possibility that an up-regulated clan 3 CYP, CYP360A8, reacts with pesticides.

Daphnia magna is a test organism used for ecological risk assessments of pesticides, but little is known about the expression levels of cytochrome P450s (CYP)s and their changes after pesticide exposure in the less than 24-h-olds used for ecotoxicity tests. In this study, D. magna juveniles were exposed to 0.2 µg/L of chlorpyrifos under the conditions for acute immobilization test as specified by the OECD test guideline for 24 h, and then the gene expression was compared between the control and chlorpyrifos-exposure groups by RNA-sequencing analysis, with a focus on CYP genes. Among 38 CYP genes expressed in the control group, seven were significantly up-regulated while two were significantly down-regulated in the chlorpyrifos-exposure group. Although the sublethal concentration of chlorpyrifos did not change their expression levels so drastically (0.8 < fold change < 2.6), CY360A8 of D. magna (DmCYP360A8), which had been proposed to be responsible for metabolism of xenobiotics, was abundantly expressed in controls yet up-regulated by chlorpyrifos. Therefore, homology modeling of DmCYP360A8 was performed based on the amino acid sequence, and then molecular docking simulations with the insecticides that were indicated to be metabolized by CYPs in D. magna were conducted. The results indicated that DmCYP360A8 could contribute to the metabolism of diazinon and chlorfenapyr but not chlorpyrifos. These findings suggest that chlorpyrifos is probably detoxified by other CYP(s) including up-regulated and/or constitutively expressed one(s).

Structural differences between the closely related RNA helicases, UAP56 and URH49, fashion distinct functional apo-complexes.

mRNA export is an essential pathway for the regulation of gene expression. In humans, closely related RNA helicases, UAP56 and URH49, shape selective mRNA export pathways through the formation of distinct complexes, known as apo-TREX and apo-AREX complexes, and their subsequent remodeling into similar ATP-bound complexes. Therefore, defining the unidentified components of the apo-AREX complex and elucidating the molecular mechanisms underlying the formation of distinct apo-complexes is key to understanding their functional divergence. In this study, we identify additional apo-AREX components physically and functionally associated with URH49. Furthermore, by comparing the structures of UAP56 and URH49 and performing an integrated analysis of their chimeric mutants, we exhibit unique structural features that would contribute to the formation of their respective complexes. This study provides insights into the specific structural and functional diversification of these two helicases that diverged from the common ancestral gene Sub2.

Objective assessment of autism spectrum disorder based on performance in structured interpersonal acting-out tasks with prosodic stability and variability.

In this study, we sought to objectively and quantitatively characterize the prosodic features of autism spectrum disorder (ASD) via the characteristics of prosody in a newly developed structured speech experiment. Male adults with high-functioning ASD and age/intelligence-matched men with typical development (TD) were asked to read 29 brief scripts aloud in response to preceding auditory stimuli. To investigate whether (1) highly structured acting-out tasks can uncover the prosodic of difference between those with ASD and TD, and (2) the prosodic stableness and flexibleness can be used for objective automatic assessment of ASD, we compared prosodic features such as fundamental frequency, intensity, and mora duration. The results indicate that individuals with ASD exhibit stable pitch registers or volume levels in some affective vocal-expression scenarios, such as those involving anger or sadness, compared with TD and those with TD. However, unstable prosody was observed in some timing control or emphasis tasks in the participants with ASD. Automatic classification of the ASD and TD groups using a support vector machine (SVM) with speech features exhibited an accuracy of 90.4%. A machine learning-based assessment of the degree of ASD core symptoms using support vector regression (SVR) also had good performance. These results may inform the development of a new easy-to-use assessment tool for ASD core symptoms using recorded audio signals.

A Structural Network Analysis of Neuronal ArhGAP21/23 Interactors by Computational Modeling.

RhoGTPase-activating proteins (RhoGAPs) play multiple roles in neuronal development; however, details of their substrate recognition system remain elusive. ArhGAP21 and ArhGAP23 are RhoGAPs that contain N-terminal PDZ and pleckstrin homology domains. In the present study, the RhoGAP domain of these ArhGAPs was computationally modeled by template-based methods and the AlphaFold2 software program, and their intrinsic RhoGTPase recognition mechanism was analyzed from the domain structures using the protein docking programs HADDOCK and HDOCK. ArhGAP21 was predicted to preferentially catalyze Cdc42, RhoA, RhoB, RhoC, and RhoG and to downregulate RhoD and Tc10 activities. Regarding ArhGAP23, RhoA and Cdc42 were deduced to be its substrates, whereas RhoD downregulation was predicted to be less efficient. The PDZ domains of ArhGAP21/23 possess the FTLRXXXVY sequence, and similar globular folding consists of antiparalleled ß-sheets and two α-helices that are conserved with PDZ domains of MAST-family proteins. A peptide docking analysis revealed the specific interaction of the ArhGAP23 PDZ domain with the PTEN C-terminus. The pleckstrin homology domain structure of ArhGAP23 was also predicted, and the functional selectivity for the interactors regulated by the folding and disordered domains in ArhGAP21 and ArhGAP23 was examined by an in silico analysis. An interaction analysis of these RhoGAPs revealed the existence of mammalian ArhGAP21/23-specific type I and type III Arf- and RhoGTPase-regulated signaling. Multiple recognition systems of RhoGTPase substrates and selective Arf-dependent localization of ArhGAP21/23 may form the basis of the functional core signaling necessary for synaptic homeostasis and axon/dendritic transport regulated by RhoGAP localization and activities.

Function of SYDE C2-RhoGAP family as signaling hubs for neuronal development deduced by computational analysis.

Recent investigations of neurological developmental disorders have revealed the Rho-family modulators such as Syde and its interactors as the candidate genes. Although the mammalian Syde proteins are reported to possess GTPase-accelerating activity for RhoA-family proteins, diverse species-specific substrate selectivities and binding partners have been described, presumably based on their evolutionary variance in the molecular organization. A comprehensive in silico analysis of Syde family proteins was performed to elucidate their molecular functions and neurodevelopmental networks. Predicted structural modeling of the RhoGAP domain may account for the molecular constraints to substrate specificity among Rho-family proteins. Deducing conserved binding motifs can extend the Syde interaction network and highlight diverse but Syde isoform-specific signaling pathways in neuronal homeostasis, differentiation, and synaptic plasticity from novel aspects of post-translational modification and proteolysis.

Effect of a novel nasal oxytocin spray with enhanced bioavailability on autism: a randomized trial.

Although intranasal oxytocin is expected to be a novel therapy for the core symptoms of autism spectrum disorder, which has currently no approved medication, the efficacy of repeated administrations was inconsistent, suggesting that the optimal dose for a single administration of oxytocin is not optimal for repeated administration. The current double-blind, placebo-controlled, multicentre, crossover trial (ClinicalTrials.gov Identifier: NCT03466671) was aimed to test the effect of TTA-121, a new formulation of intranasal oxytocin spray with an enhanced bioavailability (3.6 times higher than Syntocinon® spray, as assessed by area under the concentration-time curve in rabbit brains), which enabled us to test a wide range of multiple doses, on autism spectrum disorder core symptoms and to determine the dose-response relationship. Four-week administrations of TTA-121, at low dose once per day (3 U/day), low dose twice per day (6 U/day), high dose once per day (10 U/day), or high dose twice per day (20 U/day), and 4-week placebo were administered in a crossover manner. The primary outcome was the mean difference in the reciprocity score (range: 0-14, higher values represent worse outcomes) on the Autism Diagnostic Observation Schedule between the baseline and end point of each administration period. This trial with two administration periods and eight groups was conducted at seven university hospitals in Japan, enrolling adult males with high-functioning autism spectrum disorder. Enrolment began from June 2018 and ended December 2019. Follow-up ended March 2020. Of 109 males with high-functioning autism spectrum disorder who were randomized, 103 completed the trial. The smallest P-value, judged as the dose-response relationship, was the contrast with the peak at TTA-121 6 U/day, with inverted U-shape for both the full analysis set (P = 0.182) and per protocol set (P = 0.073). The Autism Diagnostic Observation Schedule reciprocity score, the primary outcome, was reduced in the TTA-121 6 U/day administration period compared with the placebo (full analysis set: P = 0.118, mean difference = -0.5; 95% CI: -1.1 to 0.1; per protocol set: P = 0.012, mean difference = -0.8; 95% CI: -1.3 to -0.2). The per protocol set was the analysis target population, consisting of all full analysis set participants except those who deviated from the protocol. Most dropouts from the full analysis set to the per protocol set occurred because of poor adherence to the test drug (9 of 12 in the first period and 8 of 15 in the second period). None of the secondary clinical and behavioural outcomes were significantly improved with the TTA-121 compared with the placebo in the full analysis set. A novel intranasal spray of oxytocin with enhanced bioavailability enabled us to test a wide range of multiple doses, revealing an inverted U-shape dose-response curve, with the peak at a dose that was lower than expected from previous studies. The efficacy of TTA-121 shown in the current exploratory study should be verified in a future large-scale, parallel-group trial.

3CL Protease Inhibitors with an Electrophilic Arylketone Moiety as Anti-SARS-CoV-2 Agents.

The novel coronavirus, SARS-CoV-2, has been identified as the causative agent for the current coronavirus disease (COVID-19) pandemic. 3CL protease (3CLpro) plays a pivotal role in the processing of viral polyproteins. We report peptidomimetic compounds with a unique benzothiazolyl ketone as a warhead group, which display potent activity against SARS-CoV-2 3CLpro. The most potent inhibitor YH-53 can strongly block the SARS-CoV-2 replication. X-ray structural analysis revealed that YH-53 establishes multiple hydrogen bond interactions with backbone amino acids and a covalent bond with the active site of 3CLpro. Further results from computational and experimental studies, including an in vitro absorption, distribution, metabolism, and excretion profile, in vivo pharmacokinetics, and metabolic analysis of YH-53 suggest that it has a high potential as a lead candidate to compete with COVID-19.

Oxytocin-induced increase in N,N-dimethylglycine and time course of changes in oxytocin efficacy for autism social core symptoms.

BACKGROUND: Oxytocin is expected as a novel therapeutic agent for autism spectrum disorder (ASD) core symptoms. However, previous results on the efficacy of repeated administrations of oxytocin are controversial. Recently, we reported time-course changes in the efficacy of the neuropeptide underlying the controversial effects of repeated administration; however, the underlying mechanisms remained unknown. METHODS: The current study explored metabolites representing the molecular mechanisms of oxytocin's efficacy using high-throughput metabolomics analysis on plasma collected before and after 6-week repeated intranasal administration of oxytocin (48 IU/day) or placebo in adult males with ASD (N = 106) who participated in a multi-center, parallel-group, double-blind, placebo-controlled, randomized controlled trial. RESULTS: Among the 35 metabolites measured, a significant increase in N,N-dimethylglycine was detected in the subjects administered oxytocin compared with those given placebo at a medium effect size (false discovery rate (FDR) corrected P = 0.043, d = 0.74, N = 83). Furthermore, subgroup analyses of the participants displaying a prominent time-course change in oxytocin efficacy revealed a significant effect of oxytocin on N,N-dimethylglycine levels with a large effect size (PFDR = 0.004, d = 1.13, N = 60). The increase in N,N-dimethylglycine was significantly correlated with oxytocin-induced clinical changes, assessed as changes in quantifiable characteristics of autistic facial expression, including both of improvements between baseline and 2 weeks (PFDR = 0.006, r = - 0.485, N = 43) and deteriorations between 2 and 4 weeks (PFDR = 0.032, r = 0.415, N = 37). LIMITATIONS: The metabolites changes caused by oxytocin administration were quantified using peripheral blood and therefore may not directly reflect central nervous system changes. CONCLUSION: Our findings demonstrate an association of N,N-dimethylglycine upregulation with the time-course change in the efficacy of oxytocin on autistic social deficits. Furthermore, the current findings support the involvement of the N-methyl-D-aspartate receptor and neural plasticity to the time-course change in oxytocin's efficacy. TRIAL REGISTRATION: A multi-center, parallel-group, placebo-controlled, double-blind, confirmatory trial of intranasal oxytocin in participants with autism spectrum disorders (the date registered: 30 October 2014; UMIN Clinical Trials Registry: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000017703 ) (UMIN000015264).

Antibody Screening System Using a Herpes Simplex Virus (HSV)-Based Probe To Identify a Novel Target for Receptor-Retargeted Oncolytic HSVs.

Herpes simplex virus (HSV) is a promising tool for developing oncolytic virotherapy. We recently reported a platform for receptor-retargeted oncolytic HSVs that incorporates single-chain antibodies (scFvs) into envelope glycoprotein D (gD) to mediate virus entry via tumor-associated antigens. Therefore, it would be useful to develop an efficient system that can screen antibodies that might mediate HSV entry when they are incorporated as scFvs into gD. We created an HSV-based screening probe by the genetic fusion of a gD mutant with ablated binding capability to the authentic HSV entry receptors and the antibody-binding C domain of streptococcal protein G. This engineered virus failed to enter cells through authentic receptors. In contrast, when this virus was conjugated with an antibody specific to an antigen on the cell membrane, it specifically entered cells expressing the cognate antigen. This virus was used as a probe to identify antibodies that mediate virus entry via recognition of certain molecules on the cell membrane other than authentic receptors. Using this method, we identified an antibody specific to epiregulin (EREG), which has been investigated mainly as a secreted growth factor and not necessarily for its precursor that is expressed in a transmembrane form. We constructed an scFv from the anti-EREG antibody for insertion into the retargeted HSV platform and found that the recombinant virus entered cells specifically through EREG expressed by the cells. This novel antibody-screening system may contribute to the discovery of unique and unexpected molecules that might be used for the entry of receptor-retargeted oncolytic HSVs.IMPORTANCE The tropism of the cellular entry of HSV is dependent on the binding of the envelope gD to one of its authentic receptors. This can be fully retargeted to other receptors by inserting scFvs into gD with appropriate modifications. In theory, upon binding to the engineered gD, receptors other than authentic receptors should induce a conformational change in the gD, which activates downstream mechanisms required for viral entry. However, prerequisite factors for receptors to be used as targets of a retargeted virus remain poorly understood, and it is difficult to predict which molecules might be suitable for our retargeted HSV construct. Our HSV-based probe will allow unbiased screening of antibody-antigen pairs that mediate virus entry and might be a useful tool to identify suitable pairs for our construct and to enhance our understanding of virus-cell interactions during infection by HSV and possibly other viruses.

Machine-learning classification using neuroimaging data in schizophrenia, autism, ultra-high risk and first-episode psychosis.

Neuropsychiatric disorders are diagnosed based on behavioral criteria, which makes the diagnosis challenging. Objective biomarkers such as neuroimaging are needed, and when coupled with machine learning, can assist the diagnostic decision and increase its reliability. Sixty-four schizophrenia, 36 autism spectrum disorder (ASD), and 106 typically developing individuals were analyzed. FreeSurfer was used to obtain the data from the participant's brain scans. Six classifiers were utilized to classify the subjects. Subsequently, 26 ultra-high risk for psychosis (UHR) and 17 first-episode psychosis (FEP) subjects were run through the trained classifiers. Lastly, the classifiers' output of the patient groups was correlated with their clinical severity. All six classifiers performed relatively well to distinguish the subject groups, especially support vector machine (SVM) and Logistic regression (LR). Cortical thickness and subcortical volume feature groups were most useful for the classification. LR and SVM were highly consistent with clinical indices of ASD. When UHR and FEP groups were run with the trained classifiers, majority of the cases were classified as schizophrenia, none as ASD. Overall, SVM and LR were the best performing classifiers. Cortical thickness and subcortical volume were most useful for the classification, compared to surface area. LR, SVM, and DT's output were clinically informative. The trained classifiers were able to help predict the diagnostic category of both UHR and FEP Individuals.

Calciprotein particles regulate fibroblast growth factor-23 expression in osteoblasts.

Fibroblast growth factor-23 (FGF23) is a hormone indispensable for maintaining phosphate homeostasis. In response to phosphate intake, FGF23 is secreted from osteocytes/osteoblasts and acts on the kidney to increase urinary phosphate excretion. However, the mechanism by which these cells sense phosphate intake remains elusive. Calciprotein particles are nanoparticles of calcium-phosphate precipitates bound to serum protein fetuin-A and are generated spontaneously in solution containing calcium, phosphate, and fetuin-A to be dispersed as colloids. In cultured osteoblastic cells, increase in either calcium or phosphate concentration in the medium induced FGF23 expression, which was dependent on calciprotein particle formation. When transition of calcium-phosphate precipitates from the amorphous phase to the crystalline phase was blocked by bisphosphonate, the calciprotein particle size was reduced and FGF23 expression was augmented, suggesting that small calciprotein particles containing amorphous calcium-phosphate precipitates function as a more potent FGF23 inducer than larger calciprotein particles containing crystalline calcium-phosphate precipitates. In mice, bolus phosphate administration by oral gavage transiently increased circulating calciprotein particle levels followed by a modest increase in FGF23 expression and serum FGF23 levels. However, continuous dietary phosphate load induced robust and persistent increase in circulating calciprotein particles and FGF23 levels. We confirmed by in vivo imaging that calciprotein particles injected intravenously extravasated into the bone marrow and were deposited on the inner surface of the bone, indicating that these particles have direct access to osteoblasts. Thus, we propose that osteoblasts induce FGF23 expression and secretion when they sense an increase in extracellular calciprotein particles following phosphate ingestion.

Effect of intranasal oxytocin on the core social symptoms of autism spectrum disorder: a randomized clinical trial.

Although small-scale studies have described the effects of oxytocin on social deficits in autism spectrum disorder (ASD), no large-scale study has been conducted. In this randomized, parallel-group, multicenter, placebo-controlled, double-blind trial in Japan, 106 ASD individuals (18-48 y.o.) were enrolled between Jan 2015 and March 2016. Participants were randomly assigned to a 6-week intranasal oxytocin (48IU/day, n = 53) or placebo (n = 53) group. One-hundred-three participants were analyzed. Since oxytocin reduced the primary endpoint, Autism Diagnostic Observation Schedule (ADOS) reciprocity, (from 8.5 to 7.7; P < .001) but placebo also reduced the score (8.3 to 7.2; P < .001), no between-group difference was found (effect size -0.08; 95% CI, -0.46 to 0.31; P = .69); however, plasma oxytocin was only elevated from baseline to endpoint in the oxytocin-group compared with the placebo-group (effect size -1.12; -1.53 to -0.70; P < .0001). Among the secondary endpoints, oxytocin reduced ADOS repetitive behavior (2.0 to 1.5; P < .0001) compared with placebo (2.0 to 1.8; P = .43) (effect size 0.44; 0.05 to 0.83; P = .026). In addition, the duration of gaze fixation on socially relevant regions, another secondary endpoint, was increased by oxytocin (41.2 to 52.3; P = .03) compared with placebo (45.7 to 40.4; P = .25) (effect size 0.55; 0.10 to 1.0; P = .018). No significant effects were observed for the other secondary endpoints. No significant difference in the prevalence of adverse events was observed between groups, although one participant experienced temporary gynecomastia during oxytocin administration. Based on the present findings, we cannot recommend continuous intranasal oxytocin treatment alone at the current dose and duration for treatment of the core social symptoms of high-functioning ASD in adult men, although this large-scale trial suggests oxytocin's possibility to treat ASD repetitive behavior.

Quantification of speech and synchrony in the conversation of adults with autism spectrum disorder.

Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental disorder characterized by impairments in social reciprocity and communication together with restricted interest and stereotyped behaviors. The Autism Diagnostic Observation Schedule (ADOS) is considered a 'gold standard' instrument for diagnosis of ASD and mainly depends on subjective assessments made by trained clinicians. To develop a quantitative and objective surrogate marker for ASD symptoms, we investigated speech features including F0, speech rate, speaking time, and turn-taking gaps, extracted from footage recorded during a semi-structured socially interactive situation from ADOS. We calculated not only the statistic values in a whole session of the ADOS activity but also conducted a block analysis, computing the statistical values of the prosodic features in each 8s sliding window. The block analysis identified whether participants changed volume or pitch according to the flow of the conversation. We also measured the synchrony between the participant and the ADOS administrator. Participants with high-functioning ASD showed significantly longer turn-taking gaps and a greater proportion of pause time, less variability and less synchronous changes in blockwise mean of intensity compared with those with typical development (TD) (p<0.05 corrected). In addition, the ASD group had significantly wider distribution than the TD group in the within-participant variability of blockwise mean of log F0 (p<0.05 corrected). The clinical diagnosis could be discriminated using the speech features with 89% accuracy. The features of turn-taking and pausing were significantly correlated with deficits of ASD in reciprocity (p<0.05 corrected). Additionally, regression analysis provided 1.35 of mean absolute error in the prediction of deficits in reciprocity, to which the synchrony of intensity especially contributed. The findings suggest that considering variance of speech features, interaction and synchrony with conversation partner are critical to characterize atypical features in the conversation of people with ASD.

The effects of comorbid Tourette symptoms on distress caused by compulsive-like behavior in very young children: a cross-sectional study.

BACKGROUND: Many children 4 to 6 years old exhibit compulsive-like behavior, often with comorbid Tourette symptoms, making this age group critical for investigating the effects of having comorbid Tourette symptoms with compulsive-like behavior. However, these effects have not yet been elucidated: it is unclear whether having comorbid tics with compulsive-like behavior leads to lower quality of life. This cross-sectional study aims to investigate the effect of comorbid Tourette symptoms on distress caused by compulsive-like behavior in very young children. METHODS: Self-administered questionnaires were distributed to guardians of children aged 4 to 6 attending any of the 59 public preschools in a certain ward in Tokyo, Japan. The questionnaire contained questions on the presence of Tourette symptoms, the presence of specific motor and vocal tics, frequency/intensity of compulsive-like behavior, and the distress caused by compulsive-like behavior, which was rated on a scale of 1 to 5. Additionally, questions on autism spectrum disorder (ASD) traits, attention-deficit/hyperactivity disorder (ADHD) traits, internalizing behavior traits, and externalizing behavior traits were included in the questionnaire as possible confounders of distress caused by compulsive-like behavior. Wilcoxon rank-sum tests were conducted to compare the distress caused by compulsive-like behavior and frequency/intensity of compulsive-like behavior between children in the Tourette symptoms group and the non-Tourette symptoms group. Furthermore, a stepwise regression analysis was performed to assess the effects of the independent variables on distress caused by compulsive-like behavior. Another stepwise regression analysis was performed to assess the relationship between distress caused by compulsive-like behavior and the presence of five specific motor and vocal tics. RESULTS: Of the 675 eligible participants, distress due to compulsive-like behavior was significantly higher in children in the Tourette symptoms group compared to the non-Tourette symptoms group (2.00 vs 1.00, P < 0.001). Stepwise regression analysis showed that frequency/intensity of compulsive-like behavior, being in the Tourette symptoms group, ASD traits, and internalizing behavior traits were predictors of distress due to compulsive-like behavior. Two specific tics, repetitive noises and sounds and repetitive neck, shoulder, or trunk movements, were significant predictors of distress due to compulsive-like behavior. CONCLUSIONS: Comorbid Tourette symptoms may worsen distress caused by compulsive-like behavior in children 4 to 6 years old, and specific motor and vocal tics may lead to greater distress.

Paternal age contribution to brain white matter aberrations in autism spectrum disorder.

AIM: Although advanced parental age holds an increased risk for autism spectrum disorder (ASD), its role as a potential risk factor for an atypical white matter development underlying the pathophysiology of ASD has not yet been investigated. The current study was aimed to detect white matter disparities in ASD, and further investigate the relationship of paternal and maternal age at birth with such disparities. METHODS: Thirty-nine adult males with high-functioning ASD and 37 typically developing (TD) males were analyzed in the study. The FMRIB Software Library and tract-based spatial statistics were utilized to process and analyze the diffusion tensor imaging data. RESULTS: Subjects with ASD exhibited significantly higher mean diffusivity (MD) and radial diffusivity (RD) in white matter fibers, including the association (inferior fronto-occipital fasciculus, right inferior longitudinal fasciculus, superior longitudinal fasciculi, uncinate fasciculus, and cingulum), commissural (forceps minor), and projection tracts (anterior thalamic radiation and right corticospinal tract) compared to TD subjects (Padjusted < 0.05). No differences were seen in either fractional anisotropy or axial diffusivity. Linear regression analyses assessing the relationship between parental ages and the white matter aberrations revealed a positive correlation between paternal age (PA), but not maternal age, and both MD and RD in the affected fibers (Padjusted < 0.05). Multiple regression showed that only PA was a predictor of both MD and RD. CONCLUSION: Our findings suggest that PA contributes to the white matter disparities seen in individuals with ASD compared to TD subjects.

Quantitative facial expression analysis revealed the efficacy and time course of oxytocin in autism.

Discrepancies in efficacy between single-dose and repeated administration of oxytocin for autism spectrum disorder have led researchers to hypothesize that time-course changes in efficacy are induced by repeated administrations of the peptide hormone. However, repeatable, objective, and quantitative measurement of autism spectrum disorder's core symptoms are lacking, making it difficult to examine potential time-course changes in efficacy. We tested this hypothesis using repeatable, objective, and quantitative measurement of the core symptoms of autism spectrum disorder. We examined videos recorded during semi-structured social interaction administered as the primary outcome in single-site exploratory (n = 18, crossover within-subjects design) and multisite confirmatory (n = 106, parallel-group design), double-blind, placebo-controlled 6-week trials of repeated intranasal administrations of oxytocin (48 IU/day) in adult males with autism spectrum disorder. The main outcomes were statistical representative values of objectively quantified facial expression intensity in a repeatable part of the Autism Diagnostic Observation Schedule: the maximum probability (i.e. mode) and the natural logarithm of mode on the probability density function of neutral facial expression and the natural logarithm of mode on the probability density function of happy expression. Our recent study revealed that increases in these indices characterize autistic facial expression, compared with neurotypical individuals. The current results revealed that oxytocin consistently and significantly decreased the increased natural logarithm of mode on the probability density function of neutral facial expression compared with placebo in exploratory (effect-size, -0.57; 95% CI, -1.27 to 0.13; P = 0.023) and confirmatory trials (-0.41; -0.62 to -0.20; P < 0.001). A significant interaction between time-course (at baseline, 2, 4, 6, and 8 weeks) and the efficacy of oxytocin on the natural logarithm of mode on the probability density function of neutral facial expression was found in confirmatory trial (P < 0.001). Post hoc analyses revealed maximum efficacy at 2 weeks (P < 0.001, Cohen's d = -0.78; 95% CI, -1.21 to -0.35) and deterioration of efficacy at 4 weeks (P = 0.042, Cohen's d = -0.46; 95% CI, -0.90 to -0.01) and 6 weeks (P = 0.10, Cohen's d = -0.35; 95% CI, -0.77 to 0.08), while efficacy was preserved at 2 weeks post-treatment (i.e. 8 weeks) (P < 0.001, Cohen's d = -1.24; 95% CI, -1.71 to -0.78). Quantitative facial expression analyses successfully verified the positive effects of repeated oxytocin on autistic individuals' facial expressions and demonstrated a time-course change in efficacy. The current findings support further development of an optimized regimen of oxytocin treatment.

Neuroanatomical Correlates of Advanced Paternal and Maternal Age at Birth in Autism Spectrum Disorder.

Although advanced paternal and maternal age at birth (PA/MA) increases the risk of autism spectrum disorder (ASD), the underlying neurobiological mechanisms are not fully understood. To explore the neuroanatomical correlates of advanced PA/MA, the current study conducted brain morphometric analyses in 39 high-functioning adult males with ASD and 39 age-, intellectual level-, and parental socioeconomic background-matched, typically developed (TD) males. Whole-brain analysis revealed that the regional gray matter volume (GMV) in bilateral posterior cingulate cortex (PCC) and precuneus (PCU) were significantly smaller in the individuals with ASD than in TD subjects (false discovery rate-corrected P = 0.014). Additional analyses of the constituents of GMV reduction in these brain regions revealed that the cortical thickness of the right ventral PCC was significantly thinner (P = 0.014) and the surface area of bilateral PCU was significantly smaller (left: P = 0.001; right: P = 0.049) in the adults with ASD, compared with TD subjects. Although the analyses were exploratory, the thinner cortical thickness of right ventral PCC was significantly correlated with older PA in the ASD individuals (P = 0.028). The current findings shed new light on the neurobiological mechanisms underlying the link between advanced PA and ASD.

A ternary complex model of Sirtuin4-NAD+-Glutamate dehydrogenase.

Sirtuin4 (Sirt4) is one of the mammalian homologues of Silent information regulator 2 (Sir2), which promotes the longevity of yeast, C. elegans, fruit flies and mice. Sirt4 is localized in the mitochondria, where it contributes to preventing the development of cancers and ischemic heart disease through regulating energy metabolism. The ADP-ribosylation of glutamate dehydrogenase (GDH), which is catalyzed by Sirt4, downregulates the TCA cycle. However, this reaction mechanism is obscure, because the structure of Sirt4 is unknown. We here constructed structural models of Sirt4 by homology modeling and threading, and docked nicotinamide adenine dinucleotide+ (NAD+) to Sirt4. In addition, a partial GDH structure was docked to the Sirt4-NAD+ complex model. In the ternary complex model of Sirt4-NAD+-GDH, the acetylated lysine 171 of GDH is located close to NAD+. This suggests a possible mechanism underlying the ADP-ribosylation at cysteine 172, which may occur through a transient intermediate with ADP-ribosylation at the acetylated lysine 171. These results may be useful in designing drugs for the treatment of cancers and ischemic heart disease.

Crystal structure of a Ca2+-dependent regulator of flagellar motility reveals the open-closed structural transition.

Sperm chemotaxis toward a chemoattractant is very important for the success of fertilization. Calaxin, a member of the neuronal calcium sensor protein family, directly acts on outer-arm dynein and regulates specific flagellar movement during sperm chemotaxis of ascidian, Ciona intestinalis. Here, we present the crystal structures of calaxin both in the open and closed states upon Ca2+ and Mg2+ binding. The crystal structures revealed that three of the four EF-hands of a calaxin molecule bound Ca2+ ions and that EF2 and EF3 played a critical role in the conformational transition between the open and closed states. The rotation of α7 and α8 helices induces a significant conformational change of a part of the α10 helix into the loop. The structural differences between the Ca2+- and Mg2+-bound forms indicates that EF3 in the closed state has a lower affinity for Mg2+, suggesting that calaxin tends to adopt the open state in Mg2+-bound form. SAXS data supports that Ca2+-binding causes the structural transition toward the closed state. The changes in the structural transition of the C-terminal domain may be required to bind outer-arm dynein. These results provide a novel mechanism for recognizing a target protein using a calcium sensor protein.