A case of a childhood onset developmental encephalopathy with a novel de novo truncating variant in the Membrane Protein Palmitoylated 5 (MPP5) gene.

BACKGROUND: Membrane Protein Palmitoylated 5 (MPP5) is a highly conserved apical complex protein, essential for cell polarity. Defects in neuronal cell polarity are associated with neurologic disorders. Only three patients with heterozygous MPP5 de novo variants have been reported so far, with global developmental delay, behavioral changes and in only one case epileptic seizures. OBJECTIVE: To describe a new patient with a novel truncating de novo mutation in MPP5 and to characterize in detail the epileptic phenotype and electroencephalographic features of the encephalopathy. METHODS: We identified a novel truncating de novo mutation in MPP5 in a 44 year old patient by exome sequencing (p.Ser498Phefs*15). We retrospectively analyzed his clinical and instrumental data along a thirty-year follow up. RESULT: Our patient presents with generalized tonic-clonic seizures, myoclonic and clonic seizures, non-epileptic myoclonus, tremor, severe intellectual disability, mild face dysmorphic traits, and psychosis. DISCUSSION AND CONCLUSION: We present a case of a childhood onset developmental encephalopathy with a likely-pathogenic variant in the MPP5 gene.. This represents the first complete description of the epileptic syndrome associated with the MPP5 gene.

Case report: A novel FARS2 deletion and a missense variant in a child with complicated, rapidly progressive spastic paraplegia.

Defects in FARS2 are associated with either epileptic phenotypes or a spastic paraplegia subtype known as SPG77. Here, we describe an 8-year-old patient with severe and complicated spastic paraplegia, carrying a missense variant (p.Pro361Leu) and a novel intragenic deletion in FARS2. Of note, the disease is unexpectedly progressing rapidly and in a biphasic way differently from the previously reported cases. Our study provides the first detailed molecular characterization of a FARS2 deletion and its underlying molecular mechanism, and demonstrates the need for combining different tools to improve the diagnostic rate.

Whole-genome sequencing of hMPXV1 in five Italian cases confirms the occurrence of the predominant epidemic lineage.

The ongoing outbreak of monkeypox virus (hMPXV1) is the largest recorded in historically nonendemic countries. Genomic surveillance has emerged as a pivotal tool to track the spread and monitor the evolution of viral pathogens. Therefore, to assess the genetic diversity of circulating hMPXV1 in northern Italy in June to July 2022, we sequenced and analyzed five complete genomes of viruses sampled from patients presenting with a typical course of hMPXV1 infection. Phylogenetic analysis confirmed that all five genomes belong to the predominant epidemic lineage (B.1). Inspection of genetic changes and comparison with the reference sequence showed the presence of 12 nucleotide substitutions. Seven are nonsynonymous mutations leading to amino acid changes in six proteins belonging to different functional classes. Moreover, 11 of these 12 nucleotide mutations involve GA>AA or TC>TT replacements, suggesting that host APOBEC3 enzymes are responsible for the generation of substitutions in circulating viruses. Finally, metagenomic analysis evidenced bacterial superinfection (Streptococcus pyogenes) in one patient. Through this study, we contributed to expand the number of complete genomes of viruses circulating in Italy and characterize them as belonging to the predominant outbreak lineage.

Is Brain-Derived Neurotropic Factor Methylation Involved in the Association Between Prenatal Stress and Maternal Postnatal Anxiety During the COVID-19 Pandemic?

Background: The COVID-19 pandemic is a collective trauma that may expose susceptible individuals to high levels of stress. Pregnant women represent a high-risk population, considering that pregnancy is a period of heightened neuroplasticity and susceptibility to stress through epigenetic mechanisms. Previous studies showed that the methylation status of the BDNF gene is linked with prenatal stress exposure. The goals of this study were (a) to assess the association between pandemic-related stress and postnatal anxiety and (b) to investigate the potential role of maternal BDNF methylation as a significant mediator of this association. Methods: In the present study, we report data on the association among pandemic-related stress during pregnancy, maternal BDNF methylation, and postnatal anxiety symptoms. Pandemic-related stress and postnatal anxiety were assessed through self-report instruments. BDNF methylation was estimated in 11 CpG sites in DNA from mothers' buccal cells. Complete data were available from 108 mothers. Results: Results showed that pandemic-related stress was associated with an increased risk of postnatal anxiety, r = 0.20, p < 0.05. CpG-specific BDNF methylation was significantly associated with both prenatal pandemic-related stress, r = 0.21, p < 0.05, and postnatal maternal anxious symptoms, r = 0.25, p = 0.01. Moreover, a complete mediation by the BDNF CpG6 methylation emerged between pandemic-related stress during pregnancy and postnatal maternal anxiety, ACME = 0.66, p < 0.05. Conclusion: These findings suggest that BDNF epigenetic regulation by pandemic-related stress might contribute to increase the risk of anxiety in mothers. Policymakers should prioritize the promotion of health and wellbeing in pregnant women and mothers during the present healthcare emergency.

Case Reports: Novel Missense Variants in the Filamin C Actin Binding Domain Cause Variable Phenotypes.

Filamin C is a large dimeric actin-binding protein, most prevalent in skeletal and cardiac muscle Z-discs, where it participates in sarcomere mechanical stabilization and intracellular signaling, interacting with numerous binding partners. Dominant heterozygous mutations of Filamin C gene cause several forms of myopathy and structural or arrhythmogenic cardiomyopathy. In this report we describe clinical and molecular findings of two Italian patients, in whom we identified two novel missense variants located within the Filamin C actin binding domain. Muscle imaging, histological and ultrastructural findings are also reported. Our results underline the extreme inter- and intrafamilial variability of clinical manifestations, hence the need to extend the investigation also to asymptomatic relatives, and the relevance of a broad diagnostic approach involving muscle electron microscopy, skeletal muscle magnetic resonance imaging and next generation sequencing techniques.

Contrast-enhanced digital mammography and magnetic resonance imaging: reproducibility compared to pathologic anatomy.

PURPOSE: To compare the reproducibility between contrast-enhanced digital mammography (CEDM) and magnetic resonance imaging (MRI) with the postsurgical pathologic examination. In addition, the applicability of the Breast Imaging-Reporting and Data System (BI-RADS) lexicon of MRI to CEDM was evaluated for mass lesions. METHODS: A total of 62 patients with a histologically proven diagnosis of breast cancer were included in this study, for a total of 67 lesions. Fifty-nine patients underwent both methods. The reproducibility between MRI vs CEDM and the reference standard (postoperative pathology) was assessed by considering the lesion and breast size as pivotal variables. Reproducibility was evaluated by computing the concordance correlation coefficient (CCC). Bland-Altman plots were used to depict the observed pattern of agreement as well as to estimate the associated bias. Furthermore, the pattern of agreement between the investigated methods with regard to the breast lesion characterization (i.e. mass/nonmass; shape; margins; internal enhanced characteristics) was assessed by computing the Cohen kappa and its 95% confidence interval (CI). RESULTS: The reproducibility between MRI and the reference standard and between CEDM and the reference standard showed substantial agreement, with a CCC value of 0.956 (95% CI, 0.931-0.972) and 0.950 (95% CI, 0.920-0.969), respectively. By looking at the Bland-Altman analysis, bias values of 2.344 and 1.875 mm were observed for MRI and CEDM vs reference evaluation, respectively. The agreement between MRI and CEDM is substantial with a CCC value of 0.969 (95% CI, 0.949-0.981). The Bland-Altman analysis showed bias values of -0.469 mm when comparing CEDM vs MRI. Following the Landis and Koch classification criteria, moderate agreement was observed between the two methods in describing BI-RADS descriptors of mass lesions. CONCLUSION: CEDM is able to measure and describe tumor masses comparably to MRI and can be used for surgical planning.

Hidden pandemic: COVID-19-related stress, SLC6A4 methylation, and infants' temperament at 3 months.

The COVID-19 pandemic represents a collective trauma that may have enduring stress effects during sensitive periods, such as pregnancy. Prenatal stress may result in epigenetic signatures of stress-related genes (e.g., the serotonin transporter gene, SLC6A4) that may in turn influence infants' behavioral development. In April 2020, we launched a longitudinal cohort study to assess the behavioral and epigenetic vestiges of COVID-19-related prenatal stress exposure in mothers and infants. COVID-19-related prenatal stress was retrospectively assessed at birth. SLC6A4 methylation was assessed in thirteen CpG sites in mothers and infants' buccal cells. Infants' temperament was assessed at 3-month-age. Complete data were available from 108 mother-infant dyads. Greater COVID-19-related prenatal stress was significantly associated with higher infants' SLC6A4 methylation in seven CpG sites. SLC6A4 methylation at these sites predicted infants' temperament at 3 months.

Novel SPTBN2 gene mutation and first intragenic deletion in early onset spinocerebellar ataxia type 5.

In the present study, we describe two novel cases of SCA5 with early onset. The first one, carrying a novel heterozygous de novo missense mutation in SPTBN2 gene, showed a striking very severe cerebellar atrophy and reduction of volume of the pons at a very young age (16 months). The latter, carrying the first de novo intragenic deletion so far reported in SPTBN2 gene, showed a mild cerebellar atrophy involving the hemispheres and a later onset. In both cases, for the first time, a hyperintense signal of the dentate nuclei was observed.

Loss of ap4s1 in zebrafish leads to neurodevelopmental defects resembling spastic paraplegia 52.

Autosomal recessive spastic paraplegia 52 is caused by biallelic mutations in AP4S1 which encodes a subunit of the adaptor protein complex 4 (AP-4). Using next-generation sequencing, we identified three novel unrelated SPG52 patients from a cohort of patients with cerebral palsy. The discovered variants in AP4S1 lead to reduced AP-4 complex formation in patient-derived fibroblasts. To further understand the role of AP4S1 in neuronal development and homeostasis, we engineered the first zebrafish model of AP-4 deficiency using morpholino-mediated knockdown of ap4s1. In this model, we discovered several phenotypes mimicking SPG52, including altered CNS development, locomotor deficits, and abnormal neuronal excitability.

A Novel CAPN1 Mutation Causes a Pure Hereditary Spastic Paraplegia in an Italian Family.

CAPN1 encodes calpain-1, a large subunit of µ-calpain, a calcium-activated cysteine protease widely present in the central nervous system. Mutations in CAPN1 have recently been identified in a complicated form of Hereditary Spastic Paraplegia (HSP) with a combination of cerebellar ataxia and corticomotor tract disorder (SPG76). Therefore, CAPN1 is now considered one of those genes that clinically manifest with a spectrum of disorders ranging from spasticity to cerebellar ataxia and represent a link between Spinocerebellar Ataxia and HSP, two groups of diseases previously considered separate but sharing pathophysiological pathways. We here describe clinical and molecular findings of two Italian adult siblings affected with a pure form of HSP and harboring the novel homozygote c.959delA variant (p.Tyr320Leufs*73) in the CAPN1 gene. Although the reason why mutations in CAPN1 may cause heterogeneous clinical pictures remains speculative, our findings confirm that the spectrum of the CAPN1-linked phenotypes includes pure HSP with onset during the third decade of life. Further studies are warrantied in order to clarify the mechanism underlying the differences in CAPN1 mutation clinical expression.

Antipsychotics Promote Metabolic Disorders Disrupting Cellular Lipid Metabolism and Trafficking.

Antipsychotics frequently cause obesity and related metabolic disorders that current psychopharmacological/endocrinological theories do not explain consistently. An integrative/alternative theory implies metabolic alterations happening at the cellular level. Many observations in vitro and in vivo, and pivotal observations in humans, point towards chemical properties of antipsychotics, independent of receptor binding characteristics. Being amphiphilic weak bases, antipsychotics can disrupt lysosomal function, affecting cholesterol trafficking; moreover, by chemical mimicry, antipsychotics can inhibit cholesterol biosynthesis. These two molecular adverse effects may trigger a cascade of transcriptional and biochemical events, ultimately reducing available cholesterol while increasing cholesterol precursors and fatty acids. The macroscopic manifestation of these molecular alterations includes decreased high-density lipoprotein and increased very low-density lipoprotein and triglycerides that may translate into obesity and related metabolic disorders.

ZFYVE26/SPASTIZIN and SPG11/SPATACSIN mutations in hereditary spastic paraplegia types AR-SPG15 and AR-SPG11 have different effects on autophagy and endocytosis.

ZFYVE26/Spastizin and SPG11/Spatacsin encode 2 large proteins that are mutated in hereditary autosomal-recessive spastic paraplegia/paraparesis (HSP) type 15 (AR-SPG15) and type 11 (AR-SPG11), respectively. We previously have reported that AR-SPG15-related ZFYVE26 mutations lead to autophagy defects with accumulation of immature autophagosomes. ZFYVE26 and SPG11 were found to be part of a complex including the AP5 (adaptor related protein complex 5) and to have a critical role in autophagic lysosomal reformation with identification of autophagic and lysosomal defects in cells with both AR-SPG15- and AR-SPG11-related mutations. In spite of these similarities between the 2 proteins, here we report that ZFYVE26 and SPG11 are differently involved in autophagy and endocytosis. We found that both ZFYVE26 and SPG11 interact with RAB5A and RAB11, 2 proteins regulating endosome trafficking and maturation, but only ZFYVE26 mutations affected RAB protein interactions and activation. ZFYVE26 mutations lead to defects in the fusion between autophagosomes and endosomes, while SPG11 mutations do not affect this step and lead to a milder autophagy defect. We thus demonstrate that ZFYVE26 and SPG11 affect the same cellular physiological processes, albeit at different levels: both proteins have a role in autophagic lysosome reformation, but only ZFYVE26 acts at the intersection between endocytosis and autophagy, thus representing a key player in these 2 processes. Indeed expression of the constitutively active form of RAB5A in cells with AR-SPG15-related mutations partially rescues the autophagy defect. Finally the model we propose demonstrates that autophagy and the endolysosomal pathway are central processes in the pathogenesis of these complicated forms of hereditary spastic paraparesis. Abbreviations: ALR, autophagic lysosome reformation; AP5, adaptor related protein complex 5; AR, autosomal-recessive; HSP, hereditary spastic paraplegia/paraparesis; ATG14, autophagy related 14; BafA, bafilomycin A1; BECN1, beclin 1; EBSS, Earle balanced salt solution; EEA1, early endosome antigen 1; EGF, epidermal growth factor; EGFR, epidermal growth factor receptor; GDP, guanosine diphosphate; GFP, green fluorescent protein; GTP, guanosine triphosphate; HSP, hereditary spastic paraplegias; LBPA, lysobisphosphatidic acid; MAP1LC3B/LC3B, microtubule associated protein 1 light chain 3 beta; MVBs, multivesicular bodies; PIK3C3, phosphatidylinositol 3-kinase, catalytic subunit type 3; PIK3R4, phosphoinositide-3-kinase regulatory subunit 4; PtdIns3P, phosphatidylinositol-3-phosphate; RFP, red fluorescent protein; RUBCN, RUN and cysteine rich domain containing beclin 1 interacting protein; shRNA, short hairpin RNA; SQSTM1/p62, sequestosome 1; TCC: thin corpus callosum; TF, transferrin; UVRAG, UV radiation resistance associated.

KIF5A and ALS2 Variants in a Family With Hereditary Spastic Paraplegia and Amyotrophic Lateral Sclerosis.

This paper describes the clinical evolution and the novel genetic findings in a KIF5A mutated family previously reported as affected by spastic paraparesis only. The additional evidence we report here, a homozygous ALS2 mutation detected in the proband, and the clinical evolution observed in the affected members of the family, are in line with the evidence of an overlap between Hereditary Spastic Paraplegias and Amyotrophic Lateral Sclerosis associated with variants in these genes. The proband, a 14-years-old boy, started manifesting a pure form of HSP at age 14 months. The disease rapidly progressed to a juvenile form of ALS. This boy carries a heterozygous missense variant in KIF5A p.(Glu755Lys), inherited from the father, and a homozygous missense variant in the alsin protein encoded by the ALS2 gene p.(Pro192Leu). The father shows a family history of ALS. In the last few years, he has been developing signs and symptoms of both upper and lower motor neuron degeneration, with mild bulbar motor involvement and emotional lability. The patients described in this family, confirm the continuum and partial overlap of the two clinical entities, HSP and ALS, historically viewed as distinct entities. The genetic findings in this family further substantiate the genetic bases underlying the overlap, broadening the clinical spectrum associated with KIF5A mutations.

Very preterm birth is associated with PLAGL1 gene hypomethylation at birth and discharge.

AIM: Recent findings show that DNA methylation is susceptible to very preterm (VPT) birth and to the experience of the early stay in the neonatal intensive care unit. The aim of the study was to compare PLAGL1 methylation between VPT and full-term (FT) infants at birth as well as between VPT infants at discharge and FT infants at birth. METHODS: DNA was collected from cord blood of 56 VPT and 27 FT infants at birth and from peripheral blood in VPT infants at neonatal intensive care unit discharge. Sociodemographic and neonatal variables were considered. RESULTS: PLAGL1 methylation at birth and at discharge were highly correlated in VPT infants. Lower methylation emerged in VPT infants at birth and discharge compared to FT counterparts. CONCLUSION: PLAGL1 hypomethylation emerged as a potential epigenetic mark of VPT birth. Future research is warranted to assess the functional consequences of PLAGL1 diminished methylation in VPT infants' development.

Tubulin-related cerebellar dysplasia: definition of a distinct pattern of cerebellar malformation.

OBJECTIVE: To determine the neuroimaging pattern of cerebellar dysplasia (CD) and other posterior fossa morphological anomalies associated with mutations in tubulin genes and to perform clinical and genetic correlations. METHODS: Twenty-eight patients harbouring 23 heterozygous pathogenic variants (ten novel) in tubulin genes TUBA1A (n = 10), TUBB2B (n = 8) or TUBB3 (n = 5) were studied by a brain MRI scan performed either on a 1.5 T (n = 10) or 3 T (n = 18) MR scanner with focus on the posterior fossa. RESULTS: Cerebellar anomalies were detected in 24/28 patients (86%). CD was recognised in 19/28 (68%) including cortical cerebellar dysplasia (CCD) in 18/28, either involving only the cerebellar hemispheres (12/28) or associated with vermis dysplasia (6/28). CCD was located only in the right hemisphere in 13/18 (72%), including four TUBB2B-, four TUBB3- and five TUBA1A-mutated patients, while in the other five TUBA1A cases it was located only in the left hemisphere or in both hemispheres. The postero-superior region of the cerebellar hemispheres was most frequently affected. CONCLUSIONS: The cerebellar involvement in tubulinopathies shows specific features that may be labelled as 'tubulin-related CD'. This pattern is unique and differs from other genetic causes of cerebellar dysplasia. KEY POINTS: • Cortical cerebellar dysplasia without cysts is suggestive of tubulin-related disorder. • Cerebellar dysplasia in tubulinopathies shows specific features labelled as 'tubulin-related CD'. • Focal and unilateral involvement of cerebellar hemispheres has important implications for counselling.

Clinical and Paraclinical Indicators of Motor System Impairment in Hereditary Spastic Paraplegia: A Pilot Study.

BACKGROUND: Hereditary spastic paraplegias (HSP) are a composite and genetically heterogeneous group of conditions mainly expressed by the impairment of the central motor system ("pure" forms). The involvement of other components of the central nervous system or of other systems is described in the "complicate" forms. The definition of an investigation protocol capable, by assembling clinical and paraclinical indicators to fully represent the extent of the motor system impairment, would help both the clinical handling of these conditions and contribute to our understanding of their pathogenesis. METHODS: We applied a clinical and paraclinical protocol which included tools exploring motor and non motor functioning, neurophysiology and MRI to a composite cohort of 70 molecularly defined HSP patients aged 3 to 65, to define for each indicator its significance in detailing the presence and the severity of the pathology. RESULTS: Clinically increased deep tendon reflexes and lower limb (LL) weakness are constant findings in all patients. The "complicated" forms are characterized by peripheral motor impairment, cognitive and cerebellar involvement. The Spastic Paraplegia Rating Scale efficiently reflects the severity of functional problems and correlates with disease duration. Neurophysiology consistently documents the impairment of the central motor pathway to the LLs. Nevertheless, the upper extremities and sensory system involvement is a frequent finding. MRI diffusion tensor imaging (DTI) highlighted a significant alteration of FA and MD. Combining the sampling of the various portion of the cortico-spinal tract (CST) DTI consistently discriminated patients from controls. CONCLUSION: We propose a graded clinical and paraclinical protocol for HSP phenotype definition, indicating for each tool the discriminative and descriptive capacity. Our protocol applied to 9 different forms of HSP showed that the functional impairment often extends beyond the CST. The novel DTI approach may add significant elements in disease recognition, staging and mapping.

Variants in KIF1A gene in dominant and sporadic forms of hereditary spastic paraparesis.

KIF1A gene encodes the kinesin 1a protein, an axonal motor protein working in cargo transport along neurites. Variants in KIF1A were identified in different forms of neurodegenerative diseases with dominant and recessive inheritance. Homozygous recessive mutations were found in the hereditary sensory and autonomic neuropathy type 2, HSAN2 and in a recessive subtype of hereditary spastic paraparesis, SPG30. De novo heterozygous dominant variants were found both in a dominant form of SPG30 (AD-SPG30) with one single family reported and in patients with different forms of progressive neurodegenerative diseases. We report the results of a genetic screening of 192 HSP patients, with the identification of four heterozygous variants in KIF1A in four cases, two of whom with family history for the disease. Three of the four variants fall within the motor domain, a frequent target for variants related to the AD-SPG30 subtype. The fourth variant falls downstream the motor domain in a region lacking any functional domain. The KIF1A-related patients show clinical pictures overlapping the known AD-SPG30 phenotype including pure and complicated forms with few differences. Of note, one of the families, originating from the Sicily island, carries the same variant p.S69L detected in the first AD-SPG30 family of Finnish origin reported; differently from the first one, the latter family shows a wide intra-familial phenotype variability. Overall, these data reveal a very low frequency of the AD-SPG30 subtype while confirming the presence of amino acid residues in the motor domain representing preferential targets for mutations, thereby supporting their functional relevance in kinesin 1a activity.