Common basis for orofacial clefting and cortical interneuronopathy

Newly Identified Developmental Delays in a Large Population of Children With Nonsyndromic Cleft Lip and Palate

Background

Nonsyndromic cleft lip and/or palate (NSCLP) is the most common congenital craniofacial anomaly. Early recognition of developmental delays associated with NSCLP is critical for counseling and management. This study investigates developmental delays in a large population of children with NSCLP.

Methods

This is an institutional review board-approved, retrospective analysis of children 5-21 years of age with a diagnosis of NSCLP. Demographic and clinical variables were collected for patients and a control group without NSCLP from the 2018 National Survey of Children's Health (NSCH) database.

Results

A total of 617 patients with NSCLP subjects and 29,147 NSCH participants were included. Among orofacial clefts, 45.2% were unilateral cleft lip and palate, followed by isolated cleft palate (30%), bilateral cleft lip and palate (16.4%), and isolated cleft lip (8.4%). NSCLP children with isolated cleft lip (odds ratio [OR]: 3.97), unilateral cleft lip and palate (OR: 2.17) and bilateral cleft lip and palate (OR: 2.91) had significantly higher odds of being diagnosed with attention-deficit hyperactivity disorder than the NSCH cohort. Rates of autism/pervasive developmental disorder were higher in children with isolated cleft lip than cleft lip and palate (11.5% versus 4.7%, P = 0.06), but this association was not significant. Children with isolated cleft palate had higher rates of intellectual disability, speech delay, global developmental delay, cerebral palsy, and hearing loss compared with the NSCH cohort (P < 0.05).

Conclusions

Higher rates of attention disorders and developmental delays in children with NSCLP highlight the importance of proper risk assessment and multidisciplinary management for this population.

Elementomics of 32 elements in cord serum depicts the risk of orofacial clefts: A case-control study in Shanxi, China

Maternal exposure to various metallic and non-metallic elements has been linked to the occurrence of orofacial clefts (OFCs), yet there remains a dearth of comprehensive research on the potential ramifications of simultaneous exposure to multiple elements. In this study, we investigated the individual and combined effects of element exposure on OFCs in a cohort of 168 pregnant women (49 cases and 119 controls) in the Shanxi province of northern China from 2010 to 2015. Cord serum samples were obtained from all participants to analyze the levels of 32 elements using inductively coupled plasma-mass spectrometry. The study examined the independent correlation between element concentrations and OFCs using two machine screening models, Boruta and Least Absolute Shrinkage and Selection Operator. Bayesian kernel machine regression (BKMR) was utilized to determine the combined effects of key exposure elements on OFCs and to clarify the interaction between exposed elements through the generalized additive model (GAM). The screening models identified lead (Pb), tin (Sn), iron (Fe), and cesium (Cs) as the most significant risk factors for OFC development in offspring. In the BKMR model, the probability of OFCs increased with higher overall levels of these risk elements, with Pb emerging as the primary contributor to the combined effect of the mixture. The findings of the GAM indicated that the combined exposure to Pb and Sn had a synergistic effect on the risk of developing OFCs. Analysis of elemental exposure in umbilical cord serum suggested that Pb exposure may have detrimental effects on OFC development in offspring, which may be further intensified by a synergistic interaction between Sn and Pb in the occurrence of OFCs.

Congenital cleft lip and palate and elevated risks of major psychiatric disorders: A nationwide longitudinal study

BACKGROUND

Congenital cleft lip and palate (CCLP) may be associated with major psychiatric disorders, including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia, bipolar disorder, and major depressive disorder.

METHODS

From the Taiwan National Health Insurance Research Database, 1,158 children and adolescents with CCLP and 11,580 age/sex-matched controls without CCLP were included in this study between 2001 and 2010; they were followed up until the end of 2011 to identify the aforementioned major psychiatric disorders.

RESULTS

After adjustment for age, sex, income, residence, and family history, the Cox regression model revealed a positive relationship of CCLP with subsequent schizophrenia (hazard ratio [HR]: 7.60, 95% confidence interval [CI]: 2.03-28.54), ASD (HR: 6.03, 95% CI: 1.76-20.61), and ADHD (HR: 7.33, 95% CI: 5.01-10.73).

DISCUSSION

These findings suggest that clinicians should be attentive to the presence or emergence of mental health conditions in patients with CCLP. Further studies are necessary to investigate the pathogenesis between CCLP and major psychiatric disorders.

Divergent growth of the transient brain compartments in fetuses with nonsyndromic isolated clefts involving the primary and secondary palate

Cleft lip/palate is a common orofacial malformation that often leads to speech/language difficulties as well as developmental delays in affected children, despite surgical repair. Our understanding of brain development in these children is limited. This study aimed to analyze prenatal brain development in fetuses with cleft lip/palate and controls. We examined in utero MRIs of 30 controls and 42 cleft lip/palate fetal cases and measured regional brain volumes. Cleft lip/palate was categorized into groups A (cleft lip or alveolus) and B (any combination of clefts involving the primary and secondary palates). Using a repeated-measures regression model with relative brain hemisphere volumes (%), and after adjusting for multiple comparisons, we did not identify significant differences in regional brain growth between group A and controls. Group B clefts had significantly slower weekly cerebellar growth compared with controls. We also observed divergent brain growth in transient brain structures (cortical plate, subplate, ganglionic eminence) within group B clefts, depending on severity (unilateral or bilateral) and defect location (hemisphere ipsilateral or contralateral to the defect). Further research is needed to explore the association between regional fetal brain growth and cleft lip/palate severity, with the potential to inform early neurodevelopmental biomarkers and personalized diagnostics.

Cognitive functioning and clinical characteristics of children with non-syndromic orofacial clefts: A case-control study

Introduction

The higher rate of neuropsychiatric disorders in individuals with non-syndromic orofacial clefts has been well documented by previous studies. Our goal was to identify children with non-syndromic orofacial clefts that are at risk for abnormal neurodevelopment by assessing their developmental history and present cognitive functioning.

Materials and methods

A single-center, case-controlled study was carried out at the Department of Pediatrics of the University of Pécs in Hungary. The study consisted of three phases including questionnaires to collect retrospective clinical data and psychometric tools to assess IQ and executive functioning.

Results

Forty children with non-syndromic oral clefts and 44 age-matched controls participated in the study. Apgar score at 5 min was lower for the cleft group, in addition to delays observed for potty-training and speech development. Psychiatric disorders were more common in the cleft group (15%) than in controls (4.5%), although not statistically significant with small effect size. The cleft group scored lower on the Continuous Performance Test. Subgroup analysis revealed significant associations between higher parental socio-economic status, academic, and cognitive performance in children with non-syndromic orofacial clefts. Analyzes additionally revealed significant associations between early speech and language interventions and higher scores on the Verbal Comprehension Index of the WISC-IV in these children.

Discussion

Children with non-syndromic orofacial clefts seem to be at risk for deficits involving the attention domain of the executive system. These children additionally present with difficulties that affect cognitive and speech development. Children with non-syndromic orofacial clefts show significant skill development and present with similar cognitive strengths as their peers. Longitudinal studies with larger sample sizes are needed to provide more conclusive evidence on cognitive deficits in children with non-syndromic orofacial clefts at risk for neurodevelopmental difficulties.

The Brain in Oral Clefting: A Systematic Review With Meta-Analyses

Background

Neuroimaging of individuals with non-syndromic oral clefts have revealed subtle brain structural differences compared to matched controls. Previous studies strongly suggest a unified primary dysfunction of normal brain and face development which could explain these neuroanatomical differences and the neuropsychiatric issues frequently observed in these individuals. Currently there are no studies that have assessed the overall empirical evidence of the association between oral clefts and brain structure. Our aim was to summarize the available evidence on potential brain structural differences in individuals with non-syndromic oral clefts and their matched controls.

Methods

MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Web of Science and Embase were systematically searched in September 2020 for case-control studies that reported structural brain MRI in individuals with non-syndromic oral clefts and healthy controls. Studies of syndromic oral clefts were excluded. Two review authors independently screened studies for eligibility, extracted data and assessed risk of bias with the Newcastle-Ottawa Scale. Random effects meta-analyses of mean differences (MDs) and their 95% confidence intervals (95% CI) were performed in order to compare global and regional brain MRI volumes.

Results

Ten studies from 18 records were included in the review. A total of 741 participants were analyzed. A moderate to high risk of bias was determined for the included studies. The cerebellum (MD: -12.46 cm3, 95% CI: -18.26, -6.67, n = 3 studies, 354 participants), occipital lobes (MD: -7.39, 95% CI: -12.80, -1.99, n = 2 studies, 120 participants), temporal lobes (MD: -10.53 cm3, 95% CI: -18.23, -2.82, n = 2 studies, 120 participants) and total gray matter (MD: -41.14 cm3; 95% CI: -57.36 to -24.92, n = 2 studies, 172 participants) were significantly smaller in the cleft group compared to controls.

Discussion

There may be structural brain differences between individuals with non-syndromic oral clefts and controls based on the available evidence. Improvement in study design, size, methodology and participant selection could allow a more thorough analysis and decrease study heterogeneity.

Regenerative Strategies in Cleft Palate: An Umbrella Review

(1) Background: Alveolar bone defects or decreased alveolar bone height and width may have different causes, such as cleft palate. Regenerative procedures in oro-dental defects are challenging due to anatomical factors and the distinct cell populations involved. The iliac crest bone graft remains the gold-standard for cleft palate closure. However, tissue regeneration approaches have been employed and their outcome reviewed, but no conclusions have been made about which one is the gold-standard. (2) Methods: this umbrella review aims to critically appraise the effectiveness of the current approaches in bone defects regeneration in non-syndromic patients with cleft palate. A search was performed in PubMed, Cochrane Library, Scopus, Web of Science and EMBASE databases. (3) Results: Systematic reviews of randomized and non-randomized controlled trials with or without meta-analysis were included. Nine articles were included in the qualitative analysis and five in the quantitative one. The included studies quality was evaluated with AMSTAR2. (4) Conclusions: The use of new regenerative strategies, such as bone morphogenic protein 2, appears to provide similar results regarding bone volume, filling, and height to the standard technique with the iliac crest bone graft.

Sonic Hedgehog Signaling in Cranial Neural Crest Cells Regulates Microvascular Morphogenesis in Facial Development

Sonic hedgehog (Shh) pathway disruption causes craniofacial malformations including orofacial clefts (OFCs) of the lip and palate. In normal craniofacial morphogenesis, Shh signals to multipotent cranial neural crest cells (cNCCs) and was recently discovered to regulate the angiogenic transcriptome, including expression markers of perivascular cells and pericytes. The mural cells of microvasculature, pericytes in the brain and face differentiate from cNCCs, but their role in facial development is not known. Here, we examined microvascular morphogenesis in a mouse model of Shh pathway antagonist-induced cleft lip and the impact of cNCC-specific Shh pathway activation in a cNCC-endothelial cell co-culture system. During cleft pathogenesis in vivo, disrupted microvascular morphogenesis localized with attenuated tissue outgrowth in the medial nasal processes that form the upper lip. In vitro, we found that human umbilical vein endothelial cell (HUVEC) cord formation was not affected by direct Shh pathway perturbation. However, in a co-culture system in which cNCCs directly interact with endothelial cells, cNCC-autonomous Shh pathway activity significantly prolonged endothelial cord network stability. Taken together, these findings support the premise that Shh pathway activation in cNCCs promotes pericyte-like function and microvascular stability. In addition to suggesting a previously unrecognized role for Shh signaling in facial development, these studies also identify perivascular differentiation and microvascular morphogenesis as new focuses for understanding normal and abnormal craniofacial development.

Articulation rehabilitation induces cortical plasticity in adults with non-syndromic cleft lip and palate

In this study, we investigated brain morphological changes in adults with non-syndromic cleft lip and palate (NSCLP) after articulation rehabilitation (AR). High-resolution T1 weighted brain magnetic resonance imaging data were analyzed from 45 adults with NSCLP after palatoplasty: 24 subjects were assessed before AR (bNSCLP) and 21 subjects were assessed after AR (aNSCLP). In addition, there were 24 age and sex matched controls. Intergroup differences of grey matter volume were evaluated as a comprehensive measure of the cortex; cortical thickness and cortical complexity (gyrification and fractal dimensions) were also analyzed. As compared to controls, the bNSCLP subjects exhibited altered indexes in frontal, temporal, and parietal lobes; these morphological changes are characteristic for adults with NSCLP. Importantly, as compared to the bNSCLP and control subjects, the aNSCLP subjects exhibited cortical plasticity in the regions involved in language, auditory, pronunciation planning, and execution functions. The AR-mediated cortical plasticity in aNSCLP subjects may be caused by AR-induced cortical neurogenesis, which might reflect the underlying neural mechanism during AR.

Developmental Toxicity Assessment of Piperonyl Butoxide Exposure Targeting Sonic Hedgehog Signaling and Forebrain and Face Morphogenesis in the Mouse: An in Vitro and in Vivo Study

BACKGROUND

Piperonyl butoxide (PBO) is a pesticide synergist used in residential, commercial, and agricultural settings. PBO was recently found to inhibit Sonic hedgehog (Shh) signaling, a key developmental regulatory pathway. Disruption of Shh signaling is linked to birth defects, including holoprosencephaly (HPE), a malformation of the forebrain and face thought to result from complex gene-environment interactions.

OBJECTIVES

The impact of PBO on Shh signaling in vitro and forebrain and face development in vivo was examined.

METHODS

The influence of PBO on Shh pathway transduction was assayed in mouse and human cell lines. To examine its teratogenic potential, a single dose of PBO (22-1,800mg/kg) was administered by oral gavage to C57BL/6J mice at gestational day 7.75, targeting the critical period for HPE. Gene-environment interactions were investigated using Shh+/- mice, which model human HPE-associated genetic mutations.

RESULTS

PBO attenuated Shh signaling in vitro through a mechanism similar to that of the known teratogen cyclopamine. In utero PBO exposure caused characteristic HPE facial dysmorphology including dose-dependent midface hypoplasia and hypotelorism, with a lowest observable effect level of 67mg/kg. Median forebrain deficiency characteristic of HPE was observed in severely affected animals, whereas all effective doses disrupted development of Shh-dependent transient forebrain structures that generate cortical interneurons. Normally silent heterozygous Shh null mutations exacerbated PBO teratogenicity at all doses tested, including 33mg/kg.

DISCUSSION

These findings demonstrate that prenatal PBO exposure can cause overt forebrain and face malformations or neurodevelopmental disruptions with subtle or no craniofacial dysmorphology in mice. By targeting Shh signaling as a sensitive mechanism of action and examining gene-environment interactions, this study defined a lowest observable effect level for PBO developmental toxicity in mice more than 30-fold lower than previously recognized. Human exposure to PBO and its potential contribution to etiologically complex birth defects should be rigorously examined. https://doi.org/10.1289/EHP5260.