Understanding the basis of Ehlers-Danlos syndrome in the era of the next-generation sequencing.

Ehlers-Danlos syndrome (EDS) is a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs) defined by joint laxity, skin alterations, and joint hypermobility. The latest EDS classification recognized 13 subtypes in which the clinical and genetic phenotypes are often overlapping, making the diagnosis rather difficult and strengthening the importance of the molecular diagnostic confirmation. New genetic techniques such as next-generation sequencing (NGS) gave the opportunity to identify the genetic bases of unresolved EDS types and support clinical counseling. To date, the molecular defects have been identified in 19 genes, mainly in those encoding collagen, its modifying enzymes or other constituents of the extracellular matrix (ECM). In this review we summarize the contribution of NGS technologies to the current knowledge of the genetic background in different EDS subtypes.

Emerging roles of long non-coding RNAs in the pathogenesis of Alzheimer's disease.

Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder and represents the most common form of senile dementia. The pathogenesis of AD is not yet completely understood and no curative treatment is currently available. With the recent advancement in transcriptome-wide profiling approach, several non-coding RNAs (ncRNAs) have been identified. Among them, long non-coding RNAs (lncRNAs), which are long transcripts without apparent protein-coding capacity, have received increasing interest for their involvement in a wide range of biological processes as regulatory molecules. Recent studies have suggested that lncRNAs play a role in AD pathogenesis, although their specific influences in the disorder remain to be largely unknown. Herein, we will summarize the biology and mechanisms of action of the best characterized dysregulated lncRNAs in AD, focusing the attention on their potential role in the disease pathogenesis. A deeper understanding of the molecular mechanisms and the complex network of interactions in which they are implicated should open the doors to new research considering lncRNAs as novel therapeutic targets and prognostic/diagnostic biomarkers.

Ehlers-Danlos syndrome caused by the c.934C>T, p. Arg312Cys mutation in COL1A1 gene: an Italian family without cardiovascular events.

Classic Ehlers-Danlos syndrome (cEDS) is characterized by skin hyperelasticity, joint hypermobility, increased tendency to bruise, and abnormal scarring. Mutations in type V collagen, a regulator of type I collagen fibrillogenesis, underlie this type of EDS. In this article we report a genetic and clinical analysis of an Italian family that carried missense mutation c.934 C>T (p.R312C) in the COL1A1 gene. Literature review showed an association between this missense mutation and vascular complications. Genetic screening conducted on Italian family members, revealed that vascular events are absent. In conclusion, genetic and clinical data confirm the extreme heterogeneity of EDS. Nevertheless, vascular events could be a risk factor and periodical clinical evaluation could be relevant.

PICALM Gene Methylation in Blood of Alzheimer's Disease Patients Is Associated with Cognitive Decline.

Epigenetic mechanisms might be involved in Alzheimer's disease (AD). Genetic polymorphisms in several genes, including APOE (Apolipoprotein E), PSEN1 (Presenilin 1), CR1 (Complement receptor 1), and PICALM (Phosphatidylinositol binding clathrin assembly protein), have been associated to an increased AD risk. However, data regarding methylation of these specific genes are lacking. We evaluated DNA methylation measured by quantitative bisulfite-PCR pyrosequencing in 43 AD patients and 38 healthy subjects (HS). In a multivariate age- and gender-adjusted model, PICALM methylation was decreased in AD compared to HS (mean = 3.54 and 4.63, respectively, p = 0.007). In AD, PICALM methylation level was also positively associated to Mini-Mental Scale Examination (MMSE) score (percent change 3.48%, p = 0.008). Moreover, a negative association between PICALM methylation and age was observed only in HS (percent change - 2.29%, p = 0.002). In conclusion, our data suggest a possible role of PICALM methylation in AD, particularly related to cognitive function. Given the small study sample and the associative nature of our study, further prospective investigations are required to assess the dynamics of DNA methylation in the early stages of AD development.

Epileptic seizures in autosomal dominant forms of Alzheimer's disease.

Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder and represents the most common form of dementia in the elderly. Mutations in genes encoding presenilin 1 (PSEN1), presenilin 2 (PSEN2) and amyloid precursor protein (APP) are responsible for early-onset familial AD (EOFAD). Several pieces of evidence report that patients with rare autosomal dominant forms of AD carry a significant risk to develop seizures. However, the molecular mechanisms linking epilepsy and AD are needed to be clarified: the pathophysiology of seizures in AD may be related to an increased production of amyloid-ß (Aß) peptide or structural alterations in neurons probably due to cerebrovascular changes, neurotransmitter or cytoskeletal dysfunctions. Seizures have traditionally been related to neuronal loss in the late stages of AD as a consequence of neurodegeneration, however, recent studies indicated that seizures may contribute to the emergence of AD symptoms in early stages of the disease, mainly in familial AD. So, a better understanding of possible common neural mechanisms might help to improve the clinical management of both conditions. This review aims to give a comprehensive overview and to analyze the association between epilepsy and EOFAD, focusing on possible overlapping pathological mechanisms.

A Rare Cause of Juvenile Stroke: Extracranial Carotid Artery Aneurysm with Venous Complete Reconstruction of the Carotid Bifurcation.

Extracranial carotid artery aneurysms (ECAA) are a rare cause of embolic stroke. The underlying etiology is variable, with atherosclerosis being the most common entity in older subjects. Several treatments have been developed over the last 20 years, but the preferred method remains unknown. Notwithstanding the widespread use of endovascular techniques, surgical reconstruction by means of a bifurcated venous bypass graft should be applied in younger patients. In this way, it is possible to avoid major concerns about the development of long-term intrastent restenosis, and also to spare the external carotid artery which represents the main branch for the ipsilateral cerebral and facial perfusion. We propose ECAA resection and interposition of the inverted great saphenous vein to both the internal and external carotid artery by means the use of a tributary, i.e., the Giacomini vein.

Ehlers-Danlos syndromes and epilepsy: An updated review.

The Ehlers-Danlos syndromes (EDS) comprise a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs), characterised by joint hypermobility, hyperextensibility of the skin and tissue fragility that can induce symptoms from multiple organ systems. The latest EDS nosology distinguished thirteen subtypes with an overlap of phenotypic features, making the clinical diagnosis rather difficult and highlighting the importance of molecular diagnostic confirmation. Although the nervous system is not considered a primary target of the underlying molecular defect, recently, increasing attention has been focused on neurological manifestations of EDS. Among them, epilepsy represents a frequent cause of morbidity in these syndromes and can influence the long-term evolution of these patients, but the mechanisms are needed to be clarified. The aim of this review is to give a comprehensive overview and to analyze a possible association between EDS and epilepsy, focusing on the various brain anomalies and the types of epilepsy reported in patients affected by EDS.

RETRACTED: Ehlers-Danlos syndrome caused by the c.934C>T, p. Arg312Cys mutation in COL1A1 gene: an Italian family without cardiovascular events.

The article entitled "Ehlers-Danlos syndrome caused by the c.934C>T, p. Arg312Cys mutation in COL1A1 gene: an Italian family without cardiovascular events" has been retracted because the description and characterization of the disease in a family may have been previously published. Upon publication of this article we were notified by an author of a study appearing in 2016 in another journal claiming that characteristics and symptoms of the family described closely matched their study, and that the two studies describe the same family. Whereas constituent family members appearing in both articles were not identical (differing by one member), symptoms and diagnoses of each family proband appeared to be consistent in both studies, leading to the editors' conclusion that it is likely that the same family was being described in two separate articles.The corresponding author of the article in Dermatology Online Journal was informed of this incident, and responded with the assertion that they were unaware of the study published in 2016, and provided no additional information. They further requested that their article be retracted. In light of the available information and author's request, the editors of Dermatology Online Journal have retracted this article.The original article was published on July15, 2018 and corrected on September 15, 2018.The original article was published on July15, 2018 and corrected on September 15, 2018.

A New COL3A1 Mutation in Ehlers-Danlos Syndrome Vascular Type With Different Phenotypes in the Same Family.

Vascular Ehlers-Danlos syndrome (vEDS) is a rare and severe connective tissue disorder caused by mutations in the collagen type III alpha I chain ( COL3A1) gene. We describe a pathogenetic heterozygous COL3A1 mutation c.3140 G>A, p. Gly1047Asp, identified using next-generation sequencing, in a 40-year-old Italian female. The genetic test performed on her relatives, which present different clinical phenotypes, confirmed that they carry the same mutation in heterozygous state. This finding confirms that mutations causing vEDS have an incomplete penetrance.

Next-generation sequencing and a novel COL3A1 mutation associated with vascular Ehlers-Danlos syndrome with severe intestinal involvement: a case report.

BACKGROUND: The vascular type of Ehlers-Danlos syndrome is an autosomal dominant connective tissue disorder caused by a mutation in the COL3A1 gene encoding pro-alpha1 chain of type III collagen. The vascular type of Ehlers-Danlos syndrome causes severe fragility of connective tissues with arterial and intestinal ruptures and complications in surgical and radiological treatments. CASE PRESENTATION: We present a case of a 38-year-old Italian woman who was diagnosed as having the vascular type of Ehlers-Danlos syndrome. Genetic testing, conducted by Target Enrichment approach (Agilent Technologies), identified a new mutation c.1493G>A, p.G498D in exon 21 of COL3A1 gene (heterozygous state). This mutation disrupts the normal glycine-X-Y repetitions of type III procollagen by converting glycine to aspartic acid. CONCLUSIONS: We report a new genetic mutation associated with the vascular type of Ehlers-Danlos syndrome. We also describe clinical and genetic findings that are important to understand the genotype/phenotype correlation in patients with the vascular type of Ehlers-Danlos syndrome.

Effects of particulate matter exposure on multiple sclerosis hospital admission in Lombardy region, Italy.

BACKGROUND: Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system, characterized by recurrent relapses of inflammation that cause mild to severe disability. Exposure to airborne particulate matter (PM) has been associated with acute increases in systemic inflammatory responses and neuroinflammation. In the present study, we hypothesize that exposure to PM<10µm in diameter (PM10) might increase the occurrence of MS-related hospitalizations. METHODS: We obtained daily concentrations of PM10 from 53 monitoring sites covering the study area and we identified 8287 MS-related hospitalization through hospital admission-discharge records of the Lombardy region, Italy, between 2001 and 2009. We used a Poisson regression analysis to investigate the association between exposure to PM10 and risk of hospitalization. RESULTS: A higher RR of hospital admission for MS relapse was associated with exposure to PM10 at different time intervals. The maximum effect of PM10 on MS hospitalization was found for exposure between days 0 and 7: Hospital admission for MS increased 42% (95%CI 1.39-1.45) on the days preceded by one week with PM10 levels in the highest quartile. The p-value for trend across quartiles was<0.001. CONCLUSIONS: These data support the hypothesis that air pollution may have a role in determining MS occurrence and relapses. Our findings could open new avenues for determining the pathogenic mechanisms of MS and potentially be applied to other autoimmune diseases.

Progranulin gene variability and plasma levels in bipolar disorder and schizophrenia.

Basing on the assumption that frontotemporal lobar degeneration (FTLD), schizophrenia and bipolar disorder (BPD) might share common aetiological mechanisms, we analyzed genetic variation in the FTLD risk gene progranulin (GRN) in a German population of patients with schizophrenia (n = 271) or BPD (n = 237) as compared with 574 age-, gender- and ethnicity-matched controls. Furthermore, we measured plasma progranulin levels in 26 German BPD patients as well as in 61 Italian BPD patients and 29 matched controls.A significantly decreased allelic frequency of the minor versus the wild-type allele was observed for rs2879096 (23.2 versus 34.2%, P<0.001, OR:0.63, 95%CI:0.49-0.80), rs4792938 (30.7 versus 39.7%, P = 0.005, OR: 0.70, 95%CI: 0.55-0.89) and rs5848 (30.3 versus 36.8, P = 0.007, OR: 0.71, 95%CI: 0.56-0.91). Mean±SEM progranulin plasma levels were significantly decreased in BPD patients, either Germans or Italians, as compared with controls (89.69±3.97 and 116.14±5.80 ng/ml, respectively, versus 180.81±18.39 ng/ml P<0.001) and were not correlated with age.In conclusion, GRN variability decreases the risk to develop BPD and schizophrenia, and progranulin plasma levels are significantly lower in BPD patients than in controls. Nevertheless, a larger replication analysis would be needed to confirm these preliminary results.

Selective DNA methylation of BDNF promoter in bipolar disorder: differences among patients with BDI and BDII.

The etiology of bipolar disorder (BD) is still poorly understood, involving genetic and epigenetic mechanisms as well as environmental contributions. This study aimed to investigate the degree of DNA methylation at the promoter region of the brain-derived neurotrophic factor (BDNF) gene, as one of the candidate genes associated with major psychoses, in peripheral blood mononuclear cells isolated from 94 patients with BD (BD I=49, BD II=45) and 52 healthy controls. A significant BDNF gene expression downregulation was observed in BD II 0.53±0.11%; P<0.05), but not in BD I (1.13±0.19%) patients compared with controls (CONT: 1±0.2%). Consistently, an hypermethylation of the BDNF promoter region was specifically found in BD II patients (CONT: 24.0±2.1%; BDI: 20.4±1.7%; BDII: 33.3±3.5%, P<0.05). Of note, higher levels of DNA methylation were observed in BD subjects on pharmacological treatment with mood stabilizers plus antidepressants (34.6±4.2%, predominantly BD II) compared with those exclusively on mood-stabilizing agents (21.7±1.8%; P<0.01, predominantly BD I). Moreover, among the different pharmacological therapies, lithium (20.1±3.8%, P<0.05) and valproate (23.6±2.9%, P<0.05) were associated with a significant reduction of DNA methylation compared with other drugs (35.6±4.6%). Present findings suggest selective changes in DNA methylation of BDNF promoter in subjects with BD type II and highlight the importance of epigenetic factors in mediating the onset and/or susceptibility to BD, providing new insight into the mechanisms of gene expression. Moreover, they shed light on possible mechanisms of action of mood-stabilizing compounds vs antidepressants in the treatment of BD, pointing out that BDNF regulation might be a key target for their effects.

Cerebrospinal fluid biomarkers in Progranulin mutations carriers.

Cerebrospinal fluid (CSF) biomarkers (Aß1₋42, total tau, P-181 tau) are currently used to support a clinical diagnosis of Alzheimer's disease (AD). The CSF profile in frontotemporal lobar degeneration (FTLD) caused by Progranulin (GRN) mutation is unknown. We assessed CSF biomarkers in 145 AD, 140 FTLD (20 GRN positive, 120 GRN negative) patients, and 38 controls. Taking into account the reference values used in clinical practice, GRN mutation carriers and controls did not differ significantly for any biomarker, whereas GRN negative FTLD patients had higher tau levels than controls (p < 0.001) and patients carrying GRN Thr272fs mutation (p = 0.033, Chi-Square test). Comparing CSF biomarkers mean values among groups, total tau was significantly increased in GRN negative FTLD and in mutation carriers compared with controls (p < 0.001). P-181 tau CSF was increased in AD patients and in GRN negative FTLD compared with controls (p < 0.001), but not in 17 patients carrying the Thr272fs mutation. 88.2% of mutation carriers had normal CSF tau, despite the neurodegenerative nature of FTLD. Our results suggest that GRN mutation carriers have normal or borderline CSF biomarkers. In patients with an AD-like phenotype but normal or borderline CSF biomarkers, a diagnosis of FTLD-U caused by GRN mutations should be considered.

Expression and genetic analysis of miRNAs involved in CD4+ cell activation in patients with multiple sclerosis.

MicroRNA (miRNA)-mediate RNA interference has been identified as a novel mechanism that regulates protein expression. It is recognised that miRNAs play essential roles in the immune system and for correct function in the brain. Moreover, it is now clear that abnormal miRNA expression is a common feature of several diseases involving the immune system including multiple sclerosis (MS). Expression analysis for miR-21, miR-146a and -b, miR-150, miR-155 was carried out in peripheral mononuclear cells (PBMC) from a cohort of 29 MS patients and 19 controls. Subsequently, a case control study for miR-146 rs2910164 variant was performed in an overall population of 346 MS cases and 339 controls. A statistically significant increased expression of miR-21, miR-146a and -b was observed in relapsing remitting (RR)MS patients as compared with controls (1.44±0.13 vs 0.79±0.06, P=0.036; 1.50±0.12 vs 0.84±0.08, P=0.039; 1.54±0.15 vs 0.72±0.08, P=0.001 respectively). On the contrary, no differences were found in the expression levels of both miR-150 and miR-155 in patients as compared with controls (P>0.05). The genetic association study failed to find any differences in the frequencies of rs2910164 between patients and controls. miRNA dysregulation may contribute to the pathogenesis of MS and highlights the possibility to define different disease entities with specific miRNAs profile.

Role of OLR1 and its regulating hsa-miR369-3p in Alzheimer's disease: genetics and expression analysis.

The oxidized LDL receptor 1 gene (OLR1) rs1050283 single nucleotide polymorphism (SNP) has been previously shown to be associated with Alzheimer's disease (AD). An association analysis of OLR1 was carried out in a population of 443 patients with AD as compared with 393 age-matched controls. In addition, an expression analysis of OLR1 and its regulatory hsa-miR369-3p was performed in peripheral mononuclear blood cells (PBMC) from 20 patients and 15 controls. Logistic regression analysis, adjusted for gender and apolipoprotein E (ApoE) status, showed a statistically significant association of OLR1 rs1050283 under the assumption of a dominant model (CC and CT individuals versus TT: p = 0.014, OR: 1.50, 95%CI: 1.08-2.08) and a genotypic model (TC versus TT: p = 0.002, OR: 1.61, 95%CI: 1.14-2.26). No significant differences in OLR1 expression was observed between patients and controls (p > 0.05). However, stratifying patients according to the rs1050283 status, significantly decreased relative PBMC expression levels of OLR1 were observed in carriers of CC+CT genotypes as compared with TT carriers (0.13 ± 0.013 versus 0.46 ± 0.028, p = 0.022), whereas no differences in relative expression levels of the hsa-miR369-3p were observed (p > 0.05). The effect observed was not due to the presence of the ApoE ε4 allele. The OLR1 rs1050283 SNP likely acts as a risk factor for sporadic AD. The presence of at least one C allele is associated with a decreased expression of OLR1 mRNA in the absence of hsa-miR369-3p de-regulation, suggesting that the presence of the polymorphic allele influences the binding of hsa-miR369-3p to its 3'UTR consensus sequence. Nevertheless, the limited power of the study requires further investigations with a larger sample size.

Role of hnRNP-A1 and miR-590-3p in neuronal death: genetics and expression analysis in patients with Alzheimer disease and frontotemporal lobar degeneration.

An association study of heterogeneous nuclear ribonucleoprotein (hnRNP)-A1 was carried out in a population of 274 patients with frontotemporal lobar degeneration (FTLD) and 287 with Alzheimer disease (AD) as compared with 344 age- and gender-matched controls. In addition, we evaluated expression levels of hnRNP-A1 and its regulatory microRNA (miR)-590-3p in blood cells from patients and controls. A statistically significant increased frequency of the hnRNP-A1 rs7967622 C/C genotype was observed in FTLD, but not in AD, in patients as compared to controls (23.0 versus 15.4%; p = 0.022, odds ratio [OR] 1.64, confidence interval [CI] 1.09-2.46). Stratifying according to gender, a statistically significant increased frequency of the hnRNP-A1 rs7967622 C/C genotype was observed in male patients as compared to male controls (23.1 versus 11.3%; p = 0.015, OR 2.36, CI 1.22-4.58 but not in females. Considering the rs4016671 single-nucleotide polymorphism (SNP), all patients and controls were wild type. Significantly increased hnRNP-A1 relative expression levels in peripheral blood mononuclear cells (PBMCs) was observed in patients with AD, but not with FTLD, as compared to controls (2.724 ± 0.570 versus 1.076 ± 0.187, p = 0.021). Decreased relative expression levels of hsa-miR-590-3p was observed in patients with AD versus controls (0.685 ± 0.080 versus 0.931 ± 0.111, p = 0.079), and correlated negatively with hnRNP-A1 mRNA levels (r = -0.615, p = 0.0237). According to these findings, hnRNP-A1 and its transcription regulatory factor miR-590-3p are disregulated in patients with AD, and the hnRNP-A1 rs7967622 C/C genotype is likely a risk factor for FTLD in male populations.

A novel MAPT mutation associated with the clinical phenotype of progressive nonfluent aphasia.

A number of mutations in microtubule associated protein tau gene (MAPT), causing frontotemporal lobar degeneration (FTLD) with tau pathology, are located in the four-repeated microtubule (MT) binding domains and affect the ability of tau to bind MTs. Here, we describe a novel variant lying in the second MT domain, found in a female patient diagnosed clinically with progressive nonfluent aphasia (PNFA), with a positive family history for dementia. At 65 years, she started developing progressive language deficits, characterized by expression difficulties and word coordination impairment. She came to our attention at 67 years. Her MMSE score was 22/30. A Brain CT scan showed mild diffuse cortical atrophy, ventricles' asymmetry (left > right), and very mild signs of chronic vasculopathy. Cerebrospinal fluid analysis showed normal amyloid-ß42, tau, and P-tau levels. She was diagnosed with PNFA according to current diagnostic criteria. A novel exon 10 MAPT variant was identified (g.123798G > A), which leads to an amino acidic change (p.Gly304Ser) in the second MT microtubule binding domain. In silico analysis predicted that this variant is damaging on protein structure and function. Additional 168 FTLD patients and 503 controls screened (1342 chromosomes) did not carry the variant, suggesting that it is a mutation rather than a polymorphism. The amino acid change likely compromises the ability of tau to properly regulate the dynamic behavior of microtubules.

GSK3ß genetic variability in patients with Multiple Sclerosis.

Glycogen synthase kinase-3 beta (GSK3ß) is a ubiquitous kinase that is part of multiple signaling pathways. It has neurotrophic/neuroprotective effects by mediating the actions of neurotrophic molecules in the brain, thus providing neuroprotection through modulation of energy metabolism. Notably, it has been demonstrated that GSK3ß is involved in Wnt-beta-catenin signaling, which contributes to the inhibition of myelination and remyelination processes in mammals. Three-hundred nineteen patients with MS and 294 age-matched controls were genotyped by allelic discrimination for four common GSK3ß variants (rs2199503, rs9826659, rs334558 and rs6438552) tagging about 100% of GSK-3ß variability. A statistically significant increased frequency of the rs334558 GG genotype was observed in patients as compared with controls (25.4% versus 17.7%, P=0.02; OR:1.58, 95%CI: 1.07-2.34). Stratifying MS patients according to the disease subtype, a statistically significant difference of rs334558 GG frequency was found between Relapsing Remitting (RR), but not Primary Progressive or Secondary MS, and controls (27.0% versus 17.7%, P=0.01; OR: 1.72, 95%CI: 1.13-2.61). GSK3ß rs334558 is a susceptibility factor for MS. As it is located in the promoter region, a possible explanatory mechanism could be an influence of the variant on the gene transcription rate.

Phenotypic heterogeneity of the GRN Asp22fs mutation in a large Italian kindred.

The Asp22fs(g.63_64insC) mutation in progranulin gene (GRN) has been so far reported in one patient who developed frontotemporal dementia (FTD) at the age of 65. Here, we describe the clinical heterogeneity associated with the GRN Asp22fs mutation in a large Italian family. Clinical and instrumental workup of two symptomatic carriers in two generations has been carried out, together with genetic analysis of probands and of nine asymptomatic family members. The first proband was a 47-year old male clinically diagnosed with FTD. Family history was positive and suggestive of an autosomal dominant pattern of inheritance. Evaluation of plasma GRN levels was consistent with the presence of a mutation in its encoding gene, that was demonstrated by sequencing [Asp22fs(g.63_64insC)]. Brain MRI showed multiple T2 and FLAIR hyperintense areas in the frontal lobe white matter and right hemisphere cortical atrophy. The second proband was his 79 year old uncle, presenting with mild cognitive impairment. Brain MRI showed small T2 hyperintense lesions and widespread cortical atrophy. Cerebrospinal fluid amyloid-ß, tau, and phosphotau protein levels were in both cases in the range of normality. Additional nine asymptomatic family members were studied. This family's description expands the spectrum of clinical presentations of frontotemporal lobar degeneration caused by GRN mutations, suggesting that the diagnosis could be missed in some individuals with an atypical presentation, and points up the importance of GRN plasma level evaluation.