A brain structural connectivity biomarker for autism spectrum disorder diagnosis in early childhood.

Background: Autism spectrum disorder (ASD) is associated with altered brain development, but it is unclear which specific structural changes may serve as potential diagnostic markers, particularly in young children at the age when symptoms become fully established. Furthermore, such brain markers need to meet the requirements of precision medicine and be accurate in aiding diagnosis at an individual rather than only a group level. Objective: This study aimed to identify and model brain-wide differences in structural connectivity using diffusion tensor imaging (DTI) in young ASD and typically developing (TD) children. Methods: A discovery cohort including 93 ASD and 26 TD children and two independent validation cohorts including 12 ASD and 9 TD children from three different cities in China were included. Brain-wide (294 regions) structural connectivity was measured using DTI (fractional anisotropy, FA) together with symptom severity and cognitive development. A connection matrix was constructed for each child for comparisons between ASD and TD groups. Pattern classification was performed on the discovery dataset and the resulting model was tested on the two independent validation datasets. Results: Thirty-three structural connections showed increased FA in ASD compared to TD children and associated with both autistic symptom severity and impaired general cognitive development. The majority (29/33) involved the frontal lobe and comprised five different networks with functional relevance to default mode, motor control, social recognition, language and reward. Overall, classification achieved very high accuracy of 96.77% in the discovery dataset, and 91.67% and 88.89% in the two independent validation datasets. Conclusions: Identified structural connectivity differences primarily involving the frontal cortex can very accurately distinguish novel individual ASD from TD children and may therefore represent a robust early brain biomarker which can address the requirements of precision medicine.

Infrequent Intranasal Oxytocin Followed by Positive Social Interaction Improves Symptoms in Autistic Children: A Pilot Randomized Clinical Trial.

INTRODUCTION: There are currently no approved drug interventions for social behavior dysfunction in autism spectrum disorder (ASD). Previous trials investigating effects of daily intranasal oxytocin treatment have reported inconsistent results and have not combined it with positive social interaction. However, in two preclinical studies we established that treatment every other day rather than daily is more efficacious in maintaining neural and behavioral effects by reducing receptor desensitization. OBJECTIVE: We aimed to establish whether a 6-week intranasal oxytocin compared with placebo treatment, followed by a period of positive social interaction, would produce reliable symptom improvements in children with ASD. METHODS: A pilot double-blind, randomized, crossover design trial was completed including 41 children with ASD aged 3-8 years. Primary outcomes were the Autism Diagnostic Observation Schedule-2 (ADOS-2) and social responsivity scale-2 (SRS-2). Secondary measures included cognitive, autism- and caregiver-related questionnaires, and social attention assessed using eye-tracking. RESULTS: Significant improvements were found for oxytocin relative to placebo in primary outcome measures (total ADOS-2 and SRS-2 scores, ps < 0.001) and in behavioral adaptability and repetitive behavior secondary measures. Altered SRS-2 scores were associated with increased saliva oxytocin concentrations. Additionally, oxytocin significantly increased time spent viewing dynamic social compared to geometric stimuli and the eyes of angry, happy, and neutral expression faces. There were no adverse side effects of oxytocin treatment. CONCLUSIONS: Overall, results demonstrate that a 6-week intranasal oxytocin treatment administered every other day and followed by positive social interactions can improve clinical, eye tracking, and questionnaire-based assessments of symptoms in young autistic children.

The salience of competing nonsocial objects reduces gaze toward social stimuli, but not the eyes, more in typically developing than autistic boys.

Decreased attention to social information is considered an early emerging symptom of autism spectrum disorder (ASD), although the underlying causes remain controversial. Here we explored the impact of nonsocial object salience on reduced attention to social stimuli in male ASD compared with typically developing (TD) children. Correlations with blood concentrations of neuropeptides linked with social cognition were also investigated. Eye-tracking was performed in 102 preschool-aged boys (50 ASD, 52 TD) using a paradigm with social (faces) versus nonsocial (objects) stimuli presented in pairs in two conditions where nonsocial stimulus salience was varied. Basal oxytocin (OXT) and vasopressin concentrations were measured in blood. Compared with TD boys those with ASD viewed social stimuli less only when they were paired with low-salience nonsocial objects. Additionally, boys with ASD spent less time than TD ones viewing facial features, particularly the eyes. In TD boys, OXT concentrations and cognitive development scores were positively associated with time spent viewing the eye region, whereas for boys with ASD associations with time spent viewing faces were negative. Reduced gaze toward social stimuli in ASD relative to TD individuals may therefore be influenced by how salient the paired nonsocial objects are for the latter. On the other hand, reduced interest in the eyes of faces in boys with ASD is not influenced by how salient competing nonsocial stimuli are. Basal OXT concentrations and cognitive development scores are predictive of time spent viewing social stimuli in TD boys (eyes) and those with ASD (faces) but in the opposite direction. LAY SUMMARY: Children with autism exhibit reduced attention to social paired with nonsocial stimuli compared to typically developing children. Using eye-tracking we show this difference is due to typically developing rather than autistic boys being more influenced by how interesting competing nonsocial objects are. On the other hand, reduced time looking at the eyes in autistic relative to typically developing boys is unaffected by nonsocial object salience. Time spent viewing social stimuli is associated with cognitive development and blood levels of oxytocin.

Facial emotion training as an intervention in autism spectrum disorder: A meta-analysis of randomized controlled trials.

A large number of computer-based training programs have been developed as an intervention to help individuals with autism spectrum disorders (ASD) improve their facial emotion recognition ability, as well as social skills. However, it is unclear to what extent these facial emotion training programs can produce beneficial, long-lasting, and generalizable results. Using standard meta-analytic techniques, we investigated the effects of facial emotion training including generalization and maintenance restricted to randomized control trial studies comprising a total of 595 individuals with ASD. Our findings revealed that the intervention resulted in a robust improvement in emotion recognition for individuals receiving training compared with controls. However, while there was also some evidence for generalization of training effects, the small number of studies which conducted follow-ups and assessed social skills reported that improvements were not maintained and there was no evidence for general improvement in social skills. Overall, the analysis revealed a medium effect size in training improvement indicating that facial emotion training may be an effective method for enhancing emotion recognition skills in ASD although more studies are required to assess maintenance of effects and possible general improvements in social skills. LAY SUMMARY: Facial emotion training as an intervention may be a potential way to help improve emotion recognition in autism spectrum disorder (ASD), however robust empirical support for its efficacy has not been sufficiently established. Here, we conducted a meta-analysis of previous studies to summarize the effects of facial emotion training on ASD. Our results show that the training produces a robust improvement in subsequent emotion recognition, while maintenance and generalization effects still need further investigation. To date, no experimentally verified improvements in social skills have been reported.

Oxytocin facilitates socially directed attention.

Socially directed gaze following is an important component of social interaction and communication, allowing us to attend mutually with others to objects or people so that we can share their experience and also learn from them. This type of joint social attention is impaired in disorders such as autism. Previous research has demonstrated that the neuropeptide oxytocin can facilitate attention toward social cues, although to date no study in humans has investigated its influence on socially directed gaze or on associations of the latter with autistic and empathic traits. In a within-subject, randomized, placebo-controlled trial we used eye-tracking to investigate the effects of intranasal oxytocin (24 IU) on socially directed gaze toward one of two objects in 40 adult male subjects. Subjects viewed videos of an actor and actress directing their gaze toward one of two objects by either moving only their eyes, moving both their eyes and head, or moving their eyes and head and pointing with a finger. Results showed that OXT increased the proportion of time subjects viewed the object the actor or actress were looking/pointing at across all three conditions, although unexpectedly we found no associations with trait autism or empathy under either placebo or OXT treatments. These findings demonstrate that OXT can facilitate socially directed gaze following to promote mutual attention toward objects which may be potentially beneficial therapeutically in disorders with impaired social communication and interaction.

Oxytocin Facilitation of Emotional Empathy Is Associated With Increased Eye Gaze Toward the Faces of Individuals in Emotional Contexts.

One of the most robust effects of intranasal oxytocin treatment is its enhancement of emotional empathy responses across cultures to individuals displaying emotions in realistic contexts in the Multifaceted Empathy Task (MET). However, it is not established if this effect of oxytocin on emotional empathy is due to altered visual attention toward different components of the stimulus pictures or an enhanced empathic response. In the current randomized placebo-controlled within-subject experiment on 40 healthy male individuals, we both attempted a further replication of emotional empathy enhancement by intranasal oxytocin (24 IU) and used eye-tracking measures to determine if this was associated by altered visual attention toward different components of the picture stimuli (background context, human face, and body posture). Results replicated previous findings of enhanced emotional empathy in response to both negative and positive stimuli and that this was associated with an increased proportion of time viewing the faces of humans in the pictures and a corresponding decrease in that toward the rest of the body and/or background context. Overall, our findings suggest that enhanced emotional empathy following oxytocin administration is due to increased attention to the faces of others displaying emotions and away from other contextual and social cues. Clinical Trial Registration: www.ClinicalTrials.gov Oxytocin Modulates Eye Gaze Behavior During Social Processing; registration ID: NCT03293511; URL: https://clinicaltrials.gov/ct2/show/NCT03293511.

Oxytocin biases eye-gaze to dynamic and static social images and the eyes of fearful faces: associations with trait autism.

A key functional effect of intranasal oxytocin with potential therapeutic relevance for autism-spectrum disorder is its reported facilitation of attention towards social stimuli, notably the eye region of faces. In the current randomized placebo-controlled within-subject experiment on 40 healthy males, we investigated the robustness of this facilitation of attention by intranasal oxytocin (24IU) towards social cues. Eye-tracking measures of preference for dynamic and static social vs. non-social stimuli were taken in four different paradigms where autistic individuals tend to exhibit reduced interest in social stimuli. Additionally, we investigated whether oxytocin increases attention towards the eyes relative to other salient face regions in an emotional face paradigm. Results showed that the time spent viewing both dynamic and static social vs. non-social stimuli was negatively associated with trait autism and significantly increased following intranasal oxytocin. For face stimuli, oxytocin primarily increased gaze towards the eyes of fearful expression faces but not for other face emotions. Overall, our findings demonstrate that oxytocin significantly shifts gaze preference towards social vs. non-social stimuli and to the eyes of fearful faces. Importantly, oxytocin appears generally to shift attention more towards salient social stimuli of particular relevance in the context of autism providing further support for its potential therapeutic use in autism-spectrum disorder.

Oxytocin modulation of self-referential processing is partly replicable and sensitive to oxytocin receptor genotype.

Intranasal oxytocin (OXT) has been associated with effects on diverse social-emotional domains in humans, however progress towards a therapeutic application of OXT in disorders with social-emotion impairments is currently hampered by poor replicability. Limited statistical power and individual differences in biological factors, such as oxytocin receptor (OXTR) genetics, may have contributed to these variable findings. To this end, employing a validated oxytocin-sensitive trait judgment paradigm, we present a pharmaco-genetic study aiming at (1) replicating previous findings suggesting that intranasal oxytocin (24 IU) reduces the self-referential bias in a large sample of n = 170 male subjects, (2) determining whether variations in common receptor polymorphisms (rs237887, rs2268491, rs2254298, rs53576, rs2268498) influence sensitivity to oxytocin's behavioral effects. We confirmed that in the whole sample oxytocin influenced self-other distinction in terms of reduced decision time. However, oxytocin only influenced decision time in rs53576 G carriers, whereas effects on subsequent memory performance were only found in rs2268498 TT homozygotes. In summary, the current study partially replicates our previous findings showing that oxytocin reduces the self-referential bias and suggests that sensitivity to its effects in this domain are receptor genotype dependent.

Comparison of three different eye-tracking tasks for distinguishing autistic from typically developing children and autistic symptom severity.

Altered patterns of visual social attention preference detected using eye-tracking and a variety of different paradigms are increasingly proposed as sensitive biomarkers for autism spectrum disorder. However, few eye-tracking studies have compared the relative efficacy of different paradigms to discriminate between autistic compared with typically developing children and their sensitivity to specific symptoms. To target this issue, the current study used three common eye-tracking protocols contrasting social versus nonsocial stimuli in young (2-7 years old) Chinese autistic (n = 35) and typically developing (n = 34) children matched for age and gender. Protocols included dancing people versus dynamic geometrical images, biological motion (dynamic light point walking human or cat) versus nonbiological motion (scrambled controls), and child playing with toy versus toy alone. Although all three paradigms differentiated autistic and typically developing children, the dancing people versus dynamic geometry pattern paradigm was the most effective, with autistic children showing marked reductions in visual preference for dancing people and correspondingly increased one for geometric patterns. Furthermore, this altered visual preference in autistic children was correlated with the Autism Diagnostic Observation Schedule social affect score and had the highest discrimination accuracy. Our results therefore indicate that decreased visual preference for dynamic social stimuli may be the most effective visual attention-based paradigm for use as a biomarker for autism in Chinese children. Clinical trial ID: NCT03286621 (clinicaltrials.gov); Clinical trial name: Development of Eye-tracking Based Markers for Autism in Young Children. Autism Res 2019, 12: 1529-1540. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Eye-tracking measures may be useful in aiding diagnosis and treatment of autism, although it is unclear which specific tasks are optimal. Here we compare the ability of three different social eye-gaze tasks to discriminate between autistic and typically developing young Chinese children and their sensitivity to specific autistic symptoms. Our results show that a dynamic task comparing visual preference for social (individuals dancing) versus geometric patterns is the most effective both for diagnosing autism and sensitivity to its social affect symptoms.

Foot massage evokes oxytocin release and activation of orbitofrontal cortex and superior temporal sulcus.

Massage may be an important method for increasing endogenous oxytocin concentrations and of potential therapeutic benefit in disorders with social dysfunction such as autism where basal oxytocin levels are typically reduced. Here we investigated oxytocin release and associated neural responses using functional near infrared spectroscopy (fNIRS) during hand- or machine-administered massage. 40 adult male subjects received 10 min of light foot massage either by hand or machine in a counterbalanced order and then rated pleasure, intensity, arousal and how much they would pay for the massage. Blood samples were taken before and after each massage condition to determine plasma oxytocin concentrations. Neural responses from medial and lateral orbitofrontal cortex, superior temporal sulcus and somatosensory cortex were measured (fNIRS oxy-Hb) together with skin conductance responses (SCR), ratings of the massage experience, autistic traits and sensitivity to social touch. Results showed subjects gave higher ratings of pleasure, but not intensity or arousal, after hand- compared with machine-administered massage and there were no differential effects on SCR. Subjects were also willing to pay more for the hand massage. Plasma oxytocin increased after both massage by hand or machine, but more potently after massage by hand. Both basal oxytocin concentrations and increases evoked by hand-, but not machine-administered massage, were negatively associated with trait autism and attitudes towards social touch, but massage by hand-evoked changes were significant in higher as well as lower trait individuals. Increased neural responses to hand vs. machine-administered massage were found in posterior superior temporal sulcus and medial/lateral orbitofrontal cortex but not somatosensory cortex. Orbitofrontal cortex and superior temporal cortex activation during hand massage was associated with the amount of money subjects were willing to pay and between orbitofrontal cortex activation and autism scores. Thus, hand-administered massage can potently increase oxytocin release and activity in brain regions involved in social cognition and reward but not sensory aspects of affective touch. Massage by hand induced changes in both oxytocin concentrations and neural circuits involved in processing social affective trust may have therapeutic potential in the context of autism.

Oxytocin biases men to be more or less tolerant of others' dislike dependent upon their relationship status.

The experience of being liked or disliked by others strongly influences our liking for and willingness to socialize with them. The neuropeptide oxytocin is involved in social bonding and can modify social preferences for others dependent upon their characteristics. However, it is unclear whether oxytocin affects individuals' reactions to social evaluations made by others (i.e., being liked or disliked) and if this is influenced by already having a secure partner bond (i.e., being single or in a relationship). We therefore performed a double-blind, between-subject, placebo controlled design study on 86 healthy males to investigate the effects of intranasal oxytocin (40IU) on the respective impact of being liked or disliked by others, and whether this was influenced by current relationship status. RESULTS: showed while oxytocin decreased negative reactions to being disliked in single men it had the opposite effect on men in a relationship, and this occurred primarily when dislike was expressed by females rather than males. In contrast, for men in a relationship oxytocin enhanced mood and affiliation tendency following being liked independent of the gender of the feedback provider. Thus, oxytocin may make single men looking for a potential partner more positive socially even towards females who dislike them, but has the opposite effect in men in a relationship who are not looking for a partner. These results provide further support for the context-dependency of oxytocin effects' on social preferences, and thereby the social salience hypothesis-based explanation of its actions.

Growth inhibition and induction of apoptosis in MCF-7 breast cancer cells by oridonin nanosuspension.

The mechanism for anti-tumor activity of oridonin (ORI) nanosuspension, prepared by the high pressure homogenization method, was studied using MCF-7 human breast carcinoma cells in vitro. MTT assay, observation of morphologic changes, flow cytometric analysis, and western blot analysis indicated that ORI nanosuspension could significantly intensify the in vitro anti-tumor activity to MCF-7 cells, as compared with ORI solution. Furthermore, ORI nanosuspension induced G2/M stage proliferation arrest and apoptosis in MCF-7 cells depending on its concentration. In addition, western blot analysis indicated that the pro-caspase-3 protein was not cleaved into the activated form and the expression of anti-apoptotic Bcl-2 protein decreased, on the contrary, the expression of pro-apoptotic Bax protein increased in a dose-dependent manner in ORI nanosuspension-treated cells. These observations indicated that the anti-tumor activity of ORI nanosuspension was intensified by cell-cycle arrest and apoptosis induction.

Preparation and characterization of silybin-loaded nanostructured lipid carriers.

Nanostructured lipid carriers (NLC) are a new generation of lipid nanoparticles, which are produced by controlled mixing of solid lipids with spatially incompatible liquid lipids leading to special nanostructures with improved drug incorporation and release properties. In this study, silybin-loaded nanostructured lipid carriers with various liquid lipid content were successfully prepared by the method of emulsion evaporation at a high temperature and solidification at a low temperature. The size and morphology of nanoparticles were significantly influenced by the liquid lipid content. As the liquid lipid content increased to 20 wt%, the obtained particles showed distinguished smaller size. Compared with solid lipid nanoparticles (SLN), NLC presented improved drug loading capacity which increased with increasing the liquid lipid content. The differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis indicated that the incorporation of liquid lipids could interfere with the crystallization of solid lipids. The drug in vitro release behavior from NLC displayed a biphasic drug release pattern with burst release at the initial stage and prolonged release afterwards, and the successful controlled release rate can be achieved by controlling the liquid lipid content.