Genetics screening in an Italian cohort of patients with Amyotrophic Lateral Sclerosis: the importance of early testing and its implication

INTRODUCTION

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease with an elusive etiology. While environmental factors have been considered, familial ALS cases have raised the possibility of genetic involvement. This genetic connection is increasingly evident, even in patients with sporadic ALS. We allowed access to the genetic test to all patients attending our clinic to identify the prevalence and the role of genetic variants in the development of the disease and to identify patients with potentially treatable forms of the disease.

MATERIALS AND METHODS

194 patients with probable or definite ALS, were enrolled. A comprehensive genetic testing was performed, including sequencing all exons of the SOD1 gene and testing for hexanucleotide intronic repeat expansions (G4C2) in the C9orf72 gene using fluorescent repeat-primed PCR (RP-PCR). Whole Exome NGS Sequencing (WES) was performed, followed by an in silico multigene panel targeting neuromuscular diseases, spastic paraplegia, and motor distal neuropathies. We conducted statistical analyses to compare different patient groups.

RESULTS

Clinically significant pathogenetic variants were detected in 14.43% of cases. The highest prevalence of pathogenetic variants was observed in fALS patients, but a substantial proportion of sALS patients also displayed at least one variant, either pathogenetic or of uncertain significance (VUS). The most observed pathogenetic variant was the expansion of the C9orf72 gene, which was associated with a shorter survival. SOD1 variants were found in 1.6% of fALS and 2.5% of sALS patients.

DISCUSSION

The study reveals a significant number of ALS patients carrying pathogenic or likely pathogenic variants, with a higher prevalence in familial ALS cases. The expansion of the C9orf72 gene emerges as the most common genetic cause of ALS, affecting familial and sporadic cases. Additionally, SOD1 variants are detected at an unexpectedly higher rate, even in patients without a familial history of ALS, underscoring the crucial role of genetic testing in treatment decisions and potential participation in clinical trials. We also investigated variants in genes such as TARDBP, FUS, NEK1, TBK1, and DNAJC7, shedding light on their potential involvement in ALS. These findings underscore the complexity of interpreting variants of uncertain significance (VUS) and their ethical implications in patient communication and genetic counseling for patients' relatives.

CONCLUSION

This study emphasizes the diverse genetic basis of ALS and advocates for integrating comprehensive genetic testing into diagnostic protocols. The evolving landscape of genetic therapies requires identifying all eligible patients transcending traditional familial boundaries. The presence of VUS highlights the multifaceted nature of ALS genetics, prompting further exploration of complex interactions among genetic variants, environmental factors, and disease development.

Delayed Bone Age in a Child with a Novel Loss-of-Function Variant in SETBP1 Gene Sheds Light on the Potential Role of SETBP1 Protein in Skeletal Development

Introduction

SETBP1 gene variants that decrease or eliminate protein activity have been associated with phenotypes characterized by speech apraxia and intellectual disabilities. This condition, distinctly separated from Schinzel-Giedion syndrome, is referred to as autosomal dominant mental retardation 29 (ADR29).

Case Presentation

In this report, we present the case of a 6-year-old male patient exhibiting fine and global motor skill impairments along with expressive language delay. The patient carried a novel germline, heterozygous, de novo nonsense variant in the SETBP1 gene, specifically the c.532C>T variant, which prematurely terminates protein translation at amino acid 178, p.(Gln178*), and removes more than 10% of the reference protein isoform consisting of 1,596 amino acids. According to the American College of Medical Genetics and Genomics (ACMG) guidelines, this variant has been classified as pathogenic.

Conclusion

Given the limited number of ADR29 cases reported to date, it is critical to focus attention on the phenotypic features of each new individual and seek out previously undocumented defects. The clinical findings found in our patient align with current knowledge on the correlation between the genotypes characterized by loss-of-function variants in SETBP1 gene and a particular neurological phenotype. Furthermore, the presence of a severely delayed bone age in this patient, which we report for the first time, could indicate a possible indirect but significant contribution of the SETBP1 protein in bone development and maturation processes. This finding highlights the need for further investigation into the potential effects of SETBP1 gene variants on bone health and the possible involvement of the SETBP1 protein in skeletal growth and development.

NFIA haploinsufficiency: case series and literature review

Background

NFIA-related disorder (OMIM #613735) is an autosomal dominant neurodevelopmental disorder characterized by a variable degree of cognitive impairment and non-specific dysmorphic features. To date, fewer than thirty patients affected by this disorder have been described.

Methods

Our study included three children with NFIA haploinsufficiency recruited from three medical genetics centers. Clinical presentations were recorded on a standardized case report form.

Results

All patients presented a variable degree of intellectual disability. None of the individuals in our cohort had urinary tract malformations. Three novel mutations, c.344G>A, c.261T>G, and c.887_888del are reported here.

Conclusion

NFIA haploinsufficiency can be suspected through careful observation of specific dysmorphisms, including macrocephaly and craniofacial abnormalities. Instrumental tests such as MRI and renal ultrasound provide further diagnostic clues, while genetic testing can confirm the diagnosis.

IRF2BPL: A new genotype for progressive myoclonus epilepsies

The progressive myoclonus epilepsies (PMEs) are a heterogeneous group of neurodegenerative disorders, typically presenting in late childhood. An etiologic diagnosis is achieved in about 80% of patients with PME, and genome-wide molecular studies on remaining, well-selected, undiagnosed cases can further dissect the underlying genetic heterogeneity. Through whole-exome sequencing (WES), we identified pathogenic truncating variants in the IRF2BPL gene in two, unrelated patients presenting with PME. IRF2BPL belongs to the transcriptional regulators family and it is expressed in multiple human tissues, including the brain. Recently missense and nonsense mutations in IRF2BPL were found in patients presenting with developmental delay and epileptic encephalopathy, ataxia, and movement disorders, but none with clear PME. We identified 13 other patients in the literature with myoclonic seizures and IRF2BPL variants. There was no clear genotype-phenotype correlation. With the description of these cases, the IRF2BPL gene should be considered in the list of genes to be tested in the presence of PME, in addition to patients with neurodevelopmental or movement disorders.

Netherton Syndrome Caused by Heterozygous Frameshift Mutation Combined with Homozygous c.1258A>G Polymorphism in SPINK5 Gene

Netherton syndrome (NS) is a rare autosomal recessive disorder caused by SPINK5 mutations, resulting in a deficiency in its processed protein LEKTI. It is clinically characterized by the triad of congenital ichthyosis, atopic diathesis, and hair shaft abnormalities. The SPINK5 (NM_006846.4): c.1258A>G polymorphism (rs2303067) shows a significant association with atopy and atopic dermatitis (AD), which share several clinical features with NS. We describe an NS patient, initially misdiagnosed with severe AD, who carried the heterozygous frameshift (null) mutation (NM_006846.4): c.957_960dup combined with homozygous rs2303067 in the SPINK5 gene. Histopathological examination confirmed the diagnosis, whereas an immunohistochemical study showed normal epidermal expression of LEKTI, despite the genetic findings. Our results corroborate the hypothesis that haploinsufficiency of SPINK5, in the presence of a SPINK5 null heterozygous mutation in combination with homozygous SPINK5 rs2303067 polymorphism, can be causative of an NS phenotype, impairing the function of LEKTI despite its normal expression. Due to the clinical overlap between NS and AD, we suggest performing SPINK5 genetic testing to search for the SPINK5 (NM_006846.4): c.1258A>G polymorphism (rs2303067) and ensure a correct diagnosis, mainly in doubtful cases.

PURA-Related Developmental and Epileptic Encephalopathy: Phenotypic and Genotypic Spectrum

BACKGROUND AND OBJECTIVES

Purine-rich element-binding protein A (PURA) gene encodes Pur-α, a conserved protein essential for normal postnatal brain development. Recently, a PURA syndrome characterized by intellectual disability, hypotonia, epilepsy, and dysmorphic features was suggested. The aim of this study was to define and expand the phenotypic spectrum of PURA syndrome by collecting data, including EEG, from a large cohort of affected patients.

METHODS

Data on unpublished and published cases were collected through the PURA Syndrome Foundation and the literature. Data on clinical, genetic, neuroimaging, and neurophysiologic features were obtained.

RESULTS

A cohort of 142 patients was included. Characteristics of the PURA syndrome included neonatal hypotonia, feeding difficulties, and respiratory distress. Sixty percent of the patients developed epilepsy with myoclonic, generalized tonic-clonic, focal seizures, and/or epileptic spasms. EEG showed generalized, multifocal, or focal epileptic abnormalities. Lennox-Gastaut was the most common epilepsy syndrome. Drug refractoriness was common: 33.3% achieved seizure freedom. We found 97 pathogenic variants in PURA without any clear genotype-phenotype associations.

DISCUSSION

The PURA syndrome presents with a developmental and epileptic encephalopathy with characteristics recognizable from neonatal age, which should prompt genetic screening. Sixty percent have drug-resistant epilepsy with focal or generalized seizures. We collected more than 90 pathogenic variants without observing overt genotype-phenotype associations.

IFIH1 loss-of-function variants contribute to very early-onset inflammatory bowel disease

Genetic defects of innate immunity impairing intestinal bacterial sensing are linked to the development of Inflammatory Bowel Disease (IBD). Although much evidence supports a role of the intestinal virome in gut homeostasis, most studies focus on intestinal viral composition rather than on host intestinal viral sensitivity. To demonstrate the association between the development of Very Early Onset IBD (VEOIBD) and variants in the IFIH1 gene which encodes MDA5, a key cytosolic sensor for viral nucleic acids. Whole exome sequencing (WES) was performed in two independent cohorts of children with VEOIBD enrolled in Italy (n = 18) and USA (n = 24). Luciferase reporter assays were employed to assess MDA5 activity. An enrichment analysis was performed on IFIH1 comparing 42 VEOIBD probands with 1527 unrelated individuals without gastrointestinal or immunological issues. We identified rare, likely loss-of-function (LoF), IFIH1 variants in eight patients with VEOIBD from a combined cohort of 42 children. One subject, carrying a homozygous truncating variant resulting in complete LoF, experienced neonatal-onset, pan-gastrointestinal, IBD-like enteropathy plus multiple infectious episodes. The remaining seven subjects, affected by VEOIBD without immunodeficiency, were carriers of one LoF variant in IFIH1. Among these, two patients also carried a second hypomorphic variant, with partial function apparent when MDA5 was weakly stimulated. Furthermore, IFIH1 variants were significantly enriched in children with VEOIBD as compared to controls (p = 0.007). Complete and partial MDA5 deficiency is associated with VEOIBD with variable penetrance and expressivity, suggesting a role for impaired intestinal viral sensing in IBD pathogenesis.

Novel CARMIL2 loss-of-function variants are associated with pediatric inflammatory bowel disease

CARMIL2 is required for CD28-mediated co-stimulation of NF-κB signaling in T cells and its deficiency has been associated with primary immunodeficiency and, recently, very early onset inflammatory bowel disease (IBD). Here we describe the identification of novel biallelic CARMIL2 variants in three patients presenting with pediatric-onset IBD and in one with autoimmune polyendocrine syndrome (APS). None manifested overt clinical signs of immunodeficiency before their diagnosis. The first patient presented with very early onset IBD. His brother was found homozygous for the same CARMIL2 null variant and diagnosed with APS. Two other IBD patients were found homozygous for a nonsense and a missense CARMIL2 variant, respectively, and they both experienced a complicated postoperative course marked by severe infections. Immunostaining of bowel biopsies showed reduced CARMIL2 expression in all the three patients with IBD. Western blot and immunofluorescence of transfected cells revealed an altered expression pattern of the missense variant. Our work expands the genotypic and phenotypic spectrum of CARMIL2 deficiency, which can present with either IBD or APS, aside from classic immunodeficiency manifestations. CARMIL2 should be included in the diagnostic work-up of patients with suspected monogenic IBD.

Exome sequencing and electro-clinical features in pediatric patients with very early-onset retinal dystrophies: A cohort study

BACKGROUND AND OBJECTIVE

Inherited retinal dystrophies (IRDs) are a major cause of childhood blindness. Timely diagnosis requires a high level of clinical suspicion from both neurologists and ophthalmologists and is increasingly important given recent advancements in gene therapy. We focused our study on genotype-phenotype associations in very early-onset forms of retinal dystrophy, the least well characterized and most challenging diagnostic subgroup.

METHODS

From January 12, 2015 to March 31, 2017, we prospectively performed whole exome sequencing targeted on the phenotype of non-syndromic IRDs and phenotype characterization in a cohort of 68 children affected by very early-onset inherited retinal dystrophies, defined by the onset before five years of age. Phenotype parameters included age at onset, clinical presentation, ophthalmic evaluation, electrophysiological patterns and clinical course.

RESULTS

A genetically confirmed diagnosis was achieved in 50 out of 60 (83%) families. The median age at onset was 4 months (<6 m in 70%, < 2 y in 82% of the cases). Clinical presentation was associated with visual loss and nystagmus in the majority of patients. Three (CNGB3, CNGA3 and CACNA1F) out of 22 genes considered pathogenic in the cohort, accounted for 51% of all IRD's, all within the class of stationary IRDs.

CONCLUSIONS

This study reports on the largest cohort of very early-onset retinal dystrophies, including a description of electroretinography patterns. The electro-clinical phenotype coupled with genetic diagnosis provided additional clues for child neurologists dealing with low vision and nystagmus in infancy. A high level of clinical suspicion improves the diagnosis with important implications for the future of the affected child.

Novel variants and cellular studies on patients' primary fibroblasts support a role for NEK1 missense variants in ALS pathogenesis

In the last few years, NEK1 has been identified as a new gene related to amyotrophic lateral sclerosis (ALS). Loss-of-function variants have been mostly described, although several missense variants exist, which pathogenic relevance remains to be established. We attempted to determine the contribution of NEK1 gene in an Italian cohort of 531 sporadic and familial amyotrophic lateral sclerosis (ALS) patients applying massive parallel sequencing technologies. We filtered results of NEK1 gene and identified 20 NEK1 rare variants (MAF < 0.01) in 22 patients. In particular, we found two novel frameshift variants (p.Glu929Asnfs*12 and p.Val1030Ilefs*23), 18 missense variants, including the p.Arg261His in three patients, and a novel variant in the start codon, the p.Met1?, which most likely impairs translation initiation. To clarify the role of NEK1 missense variants we investigated NEK1 expression in primary fibroblast cultures. We obtained skin biopsies from four patients with NEK1 variants and we assessed NEK1 expression by western blot and immunofluorescence. We detected a decrease in NEK1 expression in fibroblasts from patients with NEK1 variants, suggesting that missense variants in NEK1 gene may have a pathogenic role. Moreover, we observed additional variants in ALS related genes in seven patients with NEK1 variants (32%), further supporting an oligogenic ALS model.

Case Report: Intestinal Nodular Lymphoid Hyperplasia as First Manifestation of Activated PI3Kδ Syndrome Due to a Novel PIK3CD Variant

Nodular lymphoid hyperplasia (NLH) is a lymphoproliferative disease caused by non-clonal expansion of lymphoid cells in the gut mucosa. Little is known about the pathogenesis of NLH, which is often disregarded as an insignificant or para-physiologic phenomenon. We present the case of a girl with isolated diffuse NLH (extending from the stomach to the rectum) caused by activated PI3Kδ syndrome (APDS) due to the novel p.Glu525Gly variant in PIK3CD. The gain-of-function effect of the variant was confirmed by demonstration of over activation of the Akt/mTOR pathway in the patient's cells. APDS diagnosis led to treatment with sirolimus, which resulted in the complete remission of NLH and in the prevention of extra intestinal complications. In conclusion, we identify APDS as a novel cause of isolated NLH and suggest that patients with severe pan-enteric NLH should be screened for this disorder that may not be apparent on first-line immunological testing.

A novel exomal ATRX mutation with preferential transmission to offspring: A case report and review of the literature for transmission ratio distortion in ATRX families

The present case report describes an Italian family with three affected probands, who exhibited serious mental disability, which has not been associated with other anomalies, except with slight facial dysmorphism. Molecular multigenic analysis for intellectual disability identified a previously unreported variant, p.Ile1765Met (c.5295C>G) in the SNF domain of the ATRX protein (in exon 24). The identified mutation was found in a hemizygous state in all three affected probands and in a heterozygous state in the asymptomatic mother and the female sibling. With respect to the phenotypic similarities found in the patients with those described in previous studies, the consistency in the mode of inheritance and segregation of the mutation, the variant reported in the present case report may be considered as ‘likely pathogenic’. To investigate the hypothesis that the preferential transmission of the ATRX mutation observed in this family reflected a general trend, a meta-analysis into the segregation of ATRX mutations from published pedigrees, following allelic transmission from mothers who are heterozygous carriers to their offspring, was performed. A preferential transmission of the mutant allele to male offspring (58% of males inherited the mutant allele) was found; however, the bias was not statistically significant (P=0.29; χ² test).

A patient with novel MBOAT7 variant: The cerebellar atrophy is progressive and displays a peculiar neurometabolic profile

Mutations in the MBOAT7 gene have been described in 43 patients, belonging to 18 families, showing nonspecific clinical features (intellectual disability [ID], seizures, microcephaly or macrocephaly, and mild to moderate cerebellar atrophy) that make the clinical diagnosis difficult. Here we report the first Italian patient, a 22.5-year-old female, one of the oldest reported, born to apparently consanguineous parents. She shows severe ID, macrocephaly, seizures, aggressive outbursts, hyperphagia. We also documented progressive atrophy of the cerebellar vermis, that appeared not before the age of 7. The whole-exome sequencing of the trio identified a novel homozygous variant c.1057_1058delGCinsCA (p.Ala353His) in the MBOAT7 gene. The variant is considered to be likely pathogenic, since it is absent from population database and it lies in a highly conserved amino acid residue. This disorder has a neurometabolic pathogenesis, implicating a phospholipid remodeling abnormalities. A brain hydrogen-magnetic resonance spectroscopy (H-MRS) examination in our patient disclosed a peculiar neurometabolic profile in the cerebellar hemispheric region. This new finding could address the clinical suspicion of MBOAT7-related disorder, among the wide range of genetic conditions associated with ID and cerebellar atrophy. Moreover, the documented progression of cerebellar atrophy and the worsening of the disease only after some years open to the possibility of a therapeutic window after birth.

Successful fenofibrate therapy for severe and persistent hypertriglyceridemia in a boy with cirrhosis and glycerol-3-phosphate dehydrogenase 1 deficiency

Glycerol-3-phosphate dehydrogenase 1 deficiency is a rare autosomal recessive disorder caused by mutations in the GPD1 gene (GPD1; OMIM*138420). Very few cases are reported in literature. It usually manifests in early infancy with transient hypertriglyceridemia, hepatomegaly, steatosis, and fibrosis. We report the case of a 16-year-old boy followed since the age of 1 year for hepatomegaly, elevated liver enzymes, and persistent hypertriglyceridemia. Abdominal ultrasound showed diffuse liver echogenicity and liver biopsy disclosed cirrhosis with micro and macrovesicular steatosis. Next-generation sequencing for metabolic and genetic liver diseases was conducted with the identification of the homozygous mutation c.895G>A in GPD1 gene resulting in the aminocidic substitution p.G299R. Considering the persistent and progressive increase of plasma triglycerides, fenofibrate treatment was started at 15 years of age allowing triglyceride level reduction in the following 1-year follow-up.

A novel missense mutation in CAV3 gene in an Italian family with persistent hyperCKemia, myalgia and hypercholesterolemia: Double-trouble

Caveolins are essential proteins in caveolae architecture, small plasma membrane invaginations that play a key role in a variety of cellular processes, including vesicular trafficking and signal transduction. Mutations in the gene encoding caveolin-3 (CAV3) cause a broad spectrum of clinical phenotypes, ranging from isolated hyperCKemia to most severe limb girdle muscular dystrophy and cardiomyopathy. We report a novel heterozygous p.Val44Met (c.130G > A) CAV3 mutation in two brothers presenting with persistent elevation of serum creatine kinase, myalgia and hypercholesterolemia. Immunofluorescence study with anticaveolin-3 antibodies on muscle biopsy of the proband confirmed a reduced immuno-reactivity of caveolin-3 on the sarcolemma. This findings support the pathogenic effect of this novel mutation and extend the genotypic and clinical spectrum of Caveolinopathies. Finally, we discuss the hypothesis that the association between CAV3 mutations and hypercholesterolemia may not be coincidental.

Not only Alagille syndrome. Syndromic paucity of interlobular bile ducts secondary to HNF1β deficiency: a case report and literature review

Background

paucity of interlobular bile ducts is an important observation at liver biopsy in the diagnostic work-up of neonatal cholestasis. To date, other than in the Alagille syndrome, syndromic paucity of interlobular bile ducts has been documented in four cholestatic neonates with HFN1β mutations. A syndromic phenotype, known as renal cysts and diabetes syndrome (RCAD), has been identified. This is usually characterized by a wide clinical spectrum, including renal cysts, maturity-onset diabetes of the young, exocrine pancreatic insufficiency, urogenital abnormalities and a not well established liver involvement. Herein we report a novel case of paucity of interlobular bile ducts due to an HFN1β defect.

Case presentation

A 5-week-old boy was admitted to our department for cholestatic jaundice with increased gamma-glutamyl transpeptidase and an unremarkable clinical examination. He had been delivered by Caesarian section at 38 weeks’ gestation from unrelated parents, with a birth weight of 2600 g (3rd percentile). Screening for cholestatic diseases, including Alagille syndrome, was negative except for a minor pulmonary artery stenosis at echocardiography and a doubt of a thoracic butterfly hemivertebra. The finding of hyperechogenic kidneys with multiple bilateral cortical cysts at ultrasound examination, associated with moderately impaired renal function with proteinuria, polyuria and metabolic acidosis, was suggestive of ciliopathy. A liver biopsy was performed revealing paucity of interlobular bile ducts, thus the diagnosis of Alagille syndrome was reconsidered. Although genetic tests for liver cholestatic diseases were performed with negative results for Alagille syndrome (JAG1 and NOTCH2), a de-novo missense mutation of HNF1β gene was detected. At 18 months of age our patient has persistent cholestasis and his itching is not under satisfactory control.

Conclusions

Alagille syndrome may not be the only syndrome determining paucity of interlobular bile ducts in neonates presenting with cholestasis and renal impairment, especially in small for gestational age newborns. We suggest that HNF1β deficiency should also be ruled out, taking into consideration HNF1β mutations, together with Alagille syndrome, in next generation sequencing strategies in neonates with cholestasis, renal impairment and/or paucity of interlobular bile ducts at liver biopsy.

Non-syndromic isolated dominant optic atrophy caused by the p.R468C mutation in the AFG3 like matrix AAA peptidase subunit 2 gene

Autosomal dominant optic atrophy (DOA) is the most frequent form of hereditary optic atrophy, a disease presenting with considerable inter- and intra-familial clinical variability. Although a number of mutations in different genes are now known to cause DOA, many cases remain undiagnosed. In an attempt to identify the underlying genetic defect, whole exome sequencing was performed in a 19-year-old male that had been affected by isolated DOA since childhood. The exome sequencing revealed a pathogenic mutation (p.R468C, c.1402C>T) in the AFG3 like matrix AAA peptidase subunit 2 (AFG3L2) gene, a gene known to be associated with spinocerebellar ataxia. The patient did not show any signs other than DOA. Thus, the result demonstrates the possibility that mutations in the AFG3L2 gene may be a cause of isolated autosomal DOA.

Long-term rearrangement of retinal structures in a novel mutation of X-linked retinoschisis

The aim of the present study was to report a novel mutation in the retinoschisin 1 (RS1) gene in a Caucasian family affected by X-linked juvenile retinoschisis (XLRS) and to describe the long-term modification of retinal structure. Two brothers with an early onset maculopathy were diagnosed with XLRS. Fundus photography, fluorescein angiography, spectral domain optical coherence tomography and electroretinogram analyses were performed. Their sister was also examined. All subjects were screened for mutations in the RS1 gene. XLRS patients demonstrated a marked reduction of best-corrected visual acuity. SD-OCT scans reported a cystic degeneration primarily involving the inner nuclear layer, though some cysts were detected in the outer plexiform layer and in the ganglion cell layer. During the ten-year follow-up, a progressive retinal thickening and coalescence of the cysts was observed. Genetic testing revealed a novel mutation (p.Ile212Asn) in the RS1 gene in both XLRS patients, whereas their sister was not a genetic carrier. Several mutations of the RS1 gene were recognized to be responsible for XLRS. Although the correspondence between genotype and phenotype is still under debate, is reasonable that siblings affected by XLRS could share other genetic and/or epigenetic factors capable to influence clinical course of the disease.

Combined effects of genetic and non-genetic risk factors affect response to ranibizumab in exudative age-related macular degeneration

PURPOSE

To investigate whether genetic and non-genetic risk factors influence 12-month response to ranibizumab treatment for exudative age-related macular degeneration (AMD).

METHODS

A cohort of 94 Caucasian patients with unilateral exudative AMD received intravitreal ranibizumab. After a three-injection loading phase, a PRN regimen was followed. Patients were genotyped for three single-nucleotide polymorphisms: CFH rs1061170, ARMS2 rs10490924 and C3 rs2230199. Non-genetic risk factors [choroidal neovascularization (CNV) phenotype, smoking habit, hypertension and body mass index] were considered. The selected end-point was the 12-month variation of number of ETDRS letters.

RESULTS

Complement factor H (CFH) risk alleles, smoking history and arterial hypertension each independently influenced treatment response, with worse 12-month BCVA outcomes (p = 0.036, 0.037, 0.043, respectively). A significant cumulative effect of these risk factors was also observed: patients homozygous for the CFH risk alleles and with a positive smoking history showed a mean loss of 8.0 ETDRS letters (p = 0.010). Patients with CFH risk alleles, smoking history and hypertension had a mean loss of 13.9 ETDRS letters (p = 0.013). CNV phenotypes did not influence visual outcomes, nor were they associated with other genetic/non-genetic risk factors.

CONCLUSIONS

Complement factor H risk alleles, smoking history and hypertension affect the mid-term response to ranibizumab in exudative AMD.

LDL density and oxidation are modulated by PON1 promoter genotype in patients with Alzheimer's disease

Cholesterol metabolism alteration is a hot topic in the field of Alzheimer's disease (AD). However, data on plasma lipoproteins cholesterol distribution and oxidation in AD and their possible genetic determinants are lacking. The paraoxonase-1 (PON1) gene -107C/T promoter polymorphisms have been found associated with AD. One of the fundamental functions of PON1 enzyme is the inhibition of low-density lipoproteins (LDL) oxidation. We therefore evaluated plasma lipoprotein profile and LDL density and oxidation in late-onset AD patients and healthy elderly subjects, without neuroimaging evidence of cerebrovascular lesions and not on lipid-lowering treatment, and their interaction with PON1 -107C/T and apolipoprotein E (APOE) genotypes. Mean plasma total cholesterol and LDL levels were higher in AD than controls (p < 0.05). Lipoproteins cholesterol distribution shifted toward a greater prevalence of smaller, denser LDL (sd-LDL, p < 0.05) only in AD patients with PON1 -107TT genotype, who also showed increased plasma levels of oxidized LDL (ox-LDL, p = 0.02). A significant association was observed between sd-LDL and ox-LDL levels (p < 005) in AD patients. APOE genotype did not modulate lipoprotein distribution. Increased levels of sd-LDL and ox-LDL particles in the AD PON1 TT patients could be explained by the combined effect of an AD-related pro-oxidant milieu and an ineffective PON1 gene polymorphism-related antioxidant capacity. The functional correlate of the association between PON1 -107C/T polymorphism and AD may be the abnormal modulation of LDL oxidation. Ox-LDL may amplify the processes of endothelial injury promoted by vascular amyloid deposition, which represents one of the potential pathways explaining the cross-road between vascular and neurodegenerative pathomechanisms in AD.

Intrahepatic cholestasis of pregnancy: new insights into its pathogenesis

AIM

To search a specific gene expression profile in women with intrahepatic cholestasis of pregnancy (ICP) and to evaluate the maternal and foetal outcome.

METHODS

We consecutively enrolled 12 women with ICP and 12 healthy pregnant controls. The gene expression profile was assayed with the microarray technique including a panel of 5541 human genes. Microarray data were validated by real-time PCR technique.

RESULTS

Caesarean delivery was performed in eight patients with ICP versus three controls (p = 0.05). ICP women delivered at earlier gestational age than control (p < 0.001). Foetal distress was recorded in two babies, but we failed to find any correlation between bile salt concentration and foetal distress. Twenty genes potentially correlated with ICP were found differentially expressed (p < 0.05). Among these, three belong to genetic classes involved in pathogenic mechanisms of ICP: (1) pathophysiology of pruritus (GABRA2, cases versus controls = 2, upregulated gene); (2) lipid metabolism and bile composition (HLPT, cases versus controls = 0.6, down-regulated gene) and (3) protein trafficking and cytoskeleton arrangement (KIFC3, cases versus controls = 0.5, down-regulated gene).

CONCLUSIONS

Different gene expression may contribute to the complex pathogenesis of ICP. An upregulation of GABRA2 receptor may indicate that GABA may play a role in the pathogenesis of pruritus in this condition.

Is migraine a risk factor for the occurrence of eating disorders? Prevalence and biochemical evidences

The eating disorders (ED), anorexia nervosa (AN) and bulimia nervosa (BN), are severe psychiatric and somatic conditions occurring mainly in young woman. Although the aetiology is largely unknown, same evidences suggest that biological and psychological factors play a relevant role in the pathogenesis, along with monoamine, indole and same hypothalamic hormonal dysfunctions. Migraine is characterized by similar metabolic and psychological anomalies suggesting that a possible relationship exists between the two pathological conditions. To understand the possible relationship between migraine and ED, we have investigated the prevalence of migraine and the other primary headaches in a large group of AN and BN patients. In addition, we have studied the role of tyrosine metabolism in the same group of AN and BN young woman sufferers. In particular, we measured plasma levels of elusive amines: tyramine (Tyr) and octopamine (Oct) and catecholamines: noradrenalin (NE), dopamine (DA). The results of this study show that the prevalence of migraine in the woman affected by ED is very high (<75 %). The levels of Tyr and DA were higher and levels of NE were lower in the ED patients in respect to the control subjects. These biochemical findings suggest that abnormalities of limbic and hypothalamic circuitries play a role in the pathogenesis of ED. The very high prevalence of migraine in our group of ED sufferers and the biochemical profile of migraine, similar to that of ED patients shown in this study, suggest that migraine may constitute a risk factor for the occurrence of ED in young females. This hypothesis is supported by the onset of migraine attacks that initiated, in the majority of the patients, before the occurrence of ED symptoms.

The role of tyrosine metabolism in the pathogenesis of chronic migraine

OBJECTIVE

The pathogenesis of chronic migraine (CM) remains largely unknown. We hypothesized that anomalies of tyrosine metabolism, found in migraine without aura (MwwA) patients, play an important role in the transformation of MwwA into CM, since the increase in the number of MwwA attacks is the most predisposing factor for the occurrence of CM.

METHODS

To test our hypothesis we measured the plasma levels of dopamine (DA), noradrenaline (NE) and trace amines, including tyramine (TYR) and octopamine (OCT), in a group of 73 patients with CM, 13 patients with chronic tension-type headache (CTTH) and 37 controls followed in the Headache Centers of the Neurology Departments of Asti, Milan and Vicenza hospitals in Italy.

RESULTS

The plasma levels of DA and NE were several-fold higher in CM patients compared with control subjects ( P  > 0.001). The plasma levels of TYR were also extremely elevated ( P  > 0.001); furthermore, these levels progressively increased with the duration of the CM.

CONCLUSIONS

Our data support the hypothesis that altered tyrosine metabolism plays an important role in the pathogenesis of CM. The high plasma levels of TYR, a potent agonist of the trace amine associated receptors type 1 (TAAR1), may ultimately down-regulate this receptor because of loss of inhibitory presynaptic regulation, therein resulting in uncontrolled neurotransmitter release. This may produce functional metabolic consequences in the synaptic clefts of the pain matrix implicated in CM.

Migraine with aura: conventional and non-conventional treatments

Migraine with aura (MwA) is a primary headache that affects up 30% of migraine patients. Although the frequency of MwA attacks is usually low and the majority of migraine sufferers do not need prophylactic treatment(s), same particular patients do. This occurs when the neurological symptoms, that characterize the auras, determine anxiety to the migraine sufferers and when the frequency of MwA attacks is or becomes high. In this study, we review the few therapeutic conventional options specifically devoted to cure MwA attacks present in the literature together with those, recent, non-conventional.

A new class of antitumor trans-amine-amidine-Pt(II) cationic complexes: influence of chemical structure and solvent on in vitro and in vivo tumor cell proliferation

The reactions of cyclopropylamine, cyclopentylamine, and cyclohexylamine with trans-[PtCl2(NCMe)2] afforded the bis-cationic complexes trans-[Pt(amine)2(Z-amidine)2]2+[Cl-]2, 1-3. The solution behavior and biological activity have been studied in different solvents (DMSO, water, polyethylene glycol (PEG 400), and polyethylene glycol dimethyl ether (PEG-DME 500)). The biological activity was strongly influenced by the cycloaliphatic amine ring size, with trans-[Pt(NH2CH(CH2)4CH2)2{N(H) horizontal lineC(CH3)N(H)CH(CH2)4CH2}2]2+[Cl-]2 (3) being the most active compound. Complex 3 overcame both cisplatin and MDR resistance, inducing cancer cell death through p53-mediated apoptosis. Alkaline single-cell gel electrophoresis experiments indicated direct DNA damage, reasonably attributable to DNA adducts of trans-[PtCl(amine)(Z-amidine)2][Cl] species, which can evolve to produce disruptive and nonrepairable lesions on DNA, thus leading to the drug-induced programmed cancer cell death. Preliminary in vivo antitumor studies on C57BL mice bearing Lewis lung carcinoma highlighted that complex 3 promoted a significant and dose-dependent tumor growth inhibition without adverse side effects.

Hepatic expression of endocannabinoid receptors and their novel polymorphisms in primary biliary cirrhosis

BACKGROUND

The endocannabinoid system (EC) has emerged as a crucial mediator in a variety of pathophysiological conditions.

AIMS

To evaluate: (1) whether the EC system is activated in the livers of patients with primary biliary cirrhosis (PBC); (2) if genetic variations in human EC receptor genes (CB1 and CB2) may be associated with a different phenotypic expression of the disease and response to therapy.

METHODS

The expression of CB1 and CB2 receptors was studied by immunohistochemistry in liver biopsy specimens from 13 patients with PBC, and CB1 and CB2 mRNA expression was studied by real-time polymerase chain reaction testing (RT-PCR) in liver samples. In addition, genetic polymorphisms in the EC receptor gene were sought in 68 patients with PBC from Italy, 84 patients who were residents of the United States (US), and 70 controls matched for sex, age, and for geographical area with the Italian PBC patients. Genomic DNA was extracted from peripheral venous blood leucocytes with standard methods. PCR was used to amplify the coding regions of the CB1 and CB2 genes with specific primers.

RESULTS

CB1 was markedly expressed in hepatocytes and biliary epithelial cells in the livers of patients with PBC; conversely in control liver samples, it was virtually absent. CB2 was expressed in hepatocytes and in cholangiocytes, whereas it was absent from mesenchymal cells. The mRNA of both CB1 and CB2 was detected in the PBC liver samples, as demonstrated by RT-PCR. The CB1 polymorphism (1359 G/A) was present in 26.5% of Italian patients, in 22.9% of healthy controls, and in 27.4% of patients from the US (p = n.s.). The CB2 polymorphism (188-189 AA/GG) was present in 24.4 versus 30.4% of Italian and US patients with PBC, respectively, and in 28.0% of Italian controls samples (p = n.s.). Logistic regression analysis showed that advanced histological stage and the lack of response to ursodeoxycholic acid treatment were significantly correlated with the CB1 polymorphism.

CONCLUSIONS

The EC system is markedly up-regulated in the livers of patients with PBC and it may exert a role regulating adaptive mechanisms in cholestasis.

Transcriptional profiling in the lumbar spinal cord of a mouse model of amyotrophic lateral sclerosis: a role for wild-type superoxide dismutase 1 in sporadic disease?

Mice bearing mutations of copper-zinc-superoxide dismutase recapitulate spinal cord motor neuron degeneration and disease progression occurring in human amyotrophic lateral sclerosis. We have investigated the relationship between disease progression and altered gene expression by comparing the transcriptional profiles in lumbar spinal cord, fronto-parietal cortex and hippocampus of mutant G93A-SOD1, wild-type SOD1 transgenic and non-transgenic mice. Gene expression was evaluated at 55 and 110 days of age, representing pre-symptomatic and advanced disease stages of G93A mice, respectively. Whereas no significant variations were detectable in cortical and hippocampal areas, several mutation-related changes were detected in the lumbar spinal cord at the symptomatic stage, consistent with a condition of neuronal distress. Also, at both ages, we found a number of transgene-related changes, i.e. variations occurring in both transgenic groups independently of the G93A mutation, with wild-type SOD1- and G93A-SOD1-overexpressing mice displaying global transcriptional similarity at 110 days of age. Some of the changes in common between the two transgenic groups involve genes implicated in oxidative stress, inflammation, spinocerebellar degeneration and other neurodegenerative disorders. The finding that gene expressional alterations potentially associated to cellular distress are shared by wild-type and mutant human SOD1-overexpressing mice raises the possibility that mutated (in familial ALS) or otherwise dysregulated (in sporadic ALS) SOD1 expression is a common pathogenetic substrate of the disease.

Migraine prevalence in eating disorders and pathophysiological correlations

The eating disorders (ED): anorexia nervosa (AN) and Bulimia nervosa (BN) are severe psychiatric and somatic conditions occurring mainly in young woman. Although the etiology is largely unknown, same evidences suggest that biological and psychological factors play a relevant role in the pathogenesis, along with monoamine, indole and same hypothalamic hormonal dysfunctions. Migraine is characterized by similar metabolic and psychological anomalies suggesting that a possible relationship exists between the two pathological conditions. In order to understand the possible relationship between migraine and ED, we have investigated the prevalence of migraine and the other primary headaches in a large group of AN and BN patients. In addition, we have studied the role of tyrosine metabolism in the same group of AN and BN young woman sufferers. In particular, we measured plasma levels of elusive amines: tyramine (Tyr) and octopamine (Oct) and catecholamines: noradrenalin (NE), dopamine (DA). The results of this study show that the prevalence of migraine in the woman affected be EA is very high (>75%). The levels of Tyr and DA were higher and levels of NE were lower in the ED patients with respect to the control subject. These biochemical findings suggest that abnormalities of limbic and hypothalamic circuitries play a role in the pathogenesis of ED. The very high prevalence of migraine in our group of ED sufferers and the biochemical profile of migraine, similar to that ED patients have shown in this study, suggest that migraine may constitute a risk factor for the occurrence of ED in the young females. This hypothesis is supported by the onset of migraine attacks that initiated, in the majority of the patients, before the occurrence of ED symptoms.

A saturated N-acylethanolamine other than N-palmitoyl ethanolamine with anti-inflammatory properties: a neglected story

N-acylethanolamines, which include the endocannabinoid anandamide and the cannabinoid receptor-inactive saturated compounds N-palmitoyl ethanolamine and N-stearoyl ethanolamine, are ethanolamines of long-chain fatty acids degraded by fatty acid amide hydrolase (FAAH) known to accumulate in degenerating tissues and cells. Whilst much evidence supports a protective anti-inflammatory role of both anandamide and N-palmitoyl ethanolamine, very little information is available with regard to the bioactivity of N-stearoyl ethanolamine. Employing a murine model of passive IgE-induced cutaneous anaphylaxis, we have found that N-stearoyl ethanolamine is endowed with marked anti-inflammatory properties in vivo, supporting the hypothesis that endogenous N-stearoyl ethanolamine is, in analogy to N-palmitoyl ethanolamine, a bioactive signalling lipid capable of downregulating allergic inflammation in the skin. This effect, although mimicked by synthetic, non-selective, CB(1)/CB(2) receptor agonists, such as WIN55, 212-2, was not sensitive to CB(1) or CB(2) receptor antagonists, but rather was fully reversed by capsazepine, a competitive antagonist of the TRPV1 receptor. Moreover, CB(1) receptor antagonists, although effective in antagonising the WIN55,212-2-induced hypothermia, did not reduce the anti-inflammatory effect of WIN55,212-2, whilst CB(2) receptor antagonists, per se inactive, potentiated the WIN55,212-2 effect, suggesting an involvement of non-CB(1)/CB(2) receptors in the anti-inflammatory action of WIN55,212-2. All this, together with demonstration of FAAH as a major regulator of the in vivo concentrations of saturated N-stearoyl ethanolamine, in addition to N-palmitoyl ethanolamine, raise the speculation that pharmacological treatments with saturated N-acylethanolamines such as N-stearoyl ethanolamine, or alternatively FAAH inhibitors able to increase their local concentration, rather than selective CB receptor agonists, might be of promising therapeutic benefit in reducing allergic inflammation in the skin.

In vitro antitumor activity of the water soluble copper(I) complexes bearing the tris(hydroxymethyl)phosphine ligand

Monocationic hydrophilic complexes [Cu(thp)4](+) 3 and [Cu(bhpe)2](+) 4 were synthesized by ligand exchange reactions starting from the labile [Cu(CH3CN)4][PF6] precursor in the presence of an excess of the relevant hydrophilic phosphine. Complexes 3 and 4 were tested against a panel of several human tumor cell lines. Complex 3 has been shown to be about 1 order of magnitude more cytotoxic than cisplatin. Chemosensitivity tests performed on cisplatin and multidrug resistance phenotypes suggested that complex 3 acts via a different mechanism of action than the reference drug. Different short-term proliferation assays suggested that lysosomal damage is an early cellular event associated with complex 3 cytotoxicity, probably mediated by an increased production of reactive oxygen species. Cytological stains and flow cytometric analyses indicated that the phosphine copper(I) complex is able to inhibit the growth of tumor cells via G2/M cell cycle arrest and paraptosis accompanied with the loss of mitochondrial transmembrane potential.

1-(3′,4′-Dichloro-2-fluoro[1,1′-biphenyl]-4-yl)-cyclopropanecarboxylic Acid (CHF5074), a Novel γ-Secretase Modulator, Reduces Brain β-Amyloid Pathology in a Transgenic Mouse Model of Alzheimer's Disease without Causing Peripheral Toxicity

Some nonsteroidal anti-inflammatory drugs has been shown to allosterically modulate the activity of gamma-secretase, the enzymatic complex responsible for the formation of beta-amyloid (Abeta). 1-(3',4'-Dichloro-2-fluoro[1,1'-biphenyl]-4-yl)-cyclopropanecarboxylic acid (CHF5074) is a new gamma-secretase modulator, devoid of anticyclooxygenase (COX) and Notch-interfering activities in vitro. We evaluated the effects of chronic CHF5074 treatment on brain Abeta pathology in Tg2576 transgenic mice. Twenty-eight animals of 9.5 to 10.5 months of age received CHF5074-medicated diet (375 ppm) or standard diet for 17 weeks. Compared with controls, CHF5074 treatment significantly reduced the area occupied by plaques and the number of plaques in cortex (-52.2 +/- 5.6%, p = 0.0003 and -48.9 +/- 6.6%, p = 0.0004, respectively) and hippocampus (-76.7 +/- 6.4%, p = 0.004 and -66.2 +/- 10.3%, p = 0.037, respectively). Biochemical analysis confirmed the histopathological measures, with CHF5074-treated animals showing reduced total brain Abeta40 (-49.2 +/- 9.2%, p = 0.017) and Abeta42 (-43.5 +/- 9.7%, p = 0.027) levels. In a human neuroglioma cell line expressing Swedish mutated form of amyloid precursor protein (H4swe), CHF5074 reduced Abeta42 and Abeta40 secretion, with an IC50 of 3.6 and 18.4 microM, respectively, values consistent with those measured in the brain of the CHF5074-treated Tg2576 mice (6.4 +/- 0.4 microM). At 5 microM, no effects were observed on Notch intracellular cleavage in human embryonic kidney 293swe cells. CHF5074 was well tolerated by Tg2576 mice. No abnormal findings were observed upon histopathological examination of the gastrointestinal tract, indicating the absence of COX-related toxicity. Semiquantitative histochemical evaluation of goblet cells in the ileum of vehicle- and CHF5074-treated animals yielded similar results, suggesting no effects on Notch pathway. CHF5074 is therefore a promising therapeutic agent for Alzheimer's disease.

Synthesis, Characterization, and in Vitro Antitumor Properties of Tris(hydroxymethyl)phosphine Copper(I) Complexes Containing the New Bis(1,2,4-triazol-1-yl)acetate Ligand

The new sodium bis(1,2,4-triazol-1-yl)acetate ligand, Na[HC(CO(2))(tz)(2)], has been prepared in methanol solution by using 1,2,4-triazole, dibromoacetic acid, and NaOH. Treatment of the [Cu(CH(3)CN)(4)][PF(6)] acceptor with Na[HC(CO(2))(tz)(2)] or Na[HC(CO(2))[(pz(Me2))(2)] in the presence of the tris(hydroxymethyl)phosphine coligand in methanol/acetonitrile solutions produced unprecedented mononuclear copper(I) complexes of the [L(n)]Cu[P(CH(2)OH)(3)](2) (L(1), 2; L(2), 3) [(CH(3)CN)(2)Cu(P(CH(2)OH)(3))(2)]PF(6), 4. These compounds have been characterized by elemental analyses, FTIR, ESI-MS, and multinuclear (1H and 31P) NMR spectral data. The new copper(I) complexes were tested for their cytotoxic properties against a panel of several human tumor cell lines. The results reported here indicate that all the complexes showed in vitro antitumor activity similar or better than that of cisplatin, the most used metal-based antitumor drug. In particular, [HC(CO(2))(pz(Me2))(2)]Cu[P(CH(2)OH)(3)](2), 3 showed IC(50) values markedly lower than the reference compound against all tumor cell lines. Chemosensitivity tests performed on cisplatin sensitive and resistant cell lines have demonstrated that all these Cu(I) complexes were able to overcome cisplatin resistance, supporting the hypothesis of a different mechanism of action compared to that exhibited by the reference drug. Flow cytometric analysis on 2008 human ovarian carcinoma cells revealed that complex 3, chosen as the best candidate, induced a marked enlargement of both cell size and granularity, and a significant increase in the fraction of G2/M cells that, differently from cisplatin, was not accompanied by the appearance of a relevant sub-G1 fraction. Besides, no evidence of caspase-3 activation was detected in cells treated with complex 3. We hypothesize that the cytotoxic activity of the new copper(I) complex may be correlated to its ability to trigger paraptosis, a nonapoptotic mechanism of cell death.

Longitudinal analysis of immune cell phenotypes in early stage multiple sclerosis: distinctive patterns characterize MRI-active patients

To investigate whether peripheral immune abnormalities are associated with brain inflammation in multiple sclerosis, and whether differences in MRI activity are paralleled by changes in leukocyte composition, we conducted a prospective longitudinal study in patients at their clinical onset. Twenty patients presenting a first inflammatory event in the central nervous system suggestive of multiple sclerosis underwent, every 45 days for one year, immunophenotyping of 98 blood cell subsets together with brain MRI and clinical evaluation. Six patients showed intense MRI activity, six patients did not display MRI activity, while the remaining 8 patients had low (i.e. intermediate) MRI activity during the follow-up. Our results show that MRI-active and MRI-inactive patients display significant differences in ten lymphocyte subsets. Among these, there are both effector (CCR7-CD45RA-CD4+ alphabeta T cells, CCR5+ gammadelta T cells) and regulatory (DN CD28+ alphabeta T cells and CD25+CD8+ alphabeta T cells) lymphocytes pertaining to the innate and the acquired arms of the immune system. Moreover, these differences were, upon employment of a class prediction procedure based on "support vector machines" algorithm utilizing leave-one-out cross validation procedures, able to correctly assign patients to their respective MRI activity group. All 6 MRI-active and 6 MRI-inactive patients were correctly classified, and, upon application of a class prediction model in an unsupervised manner to the 8 patients with intermediate MRI activity, 6 were predicted as MRI-active and 2 as MRI-inactive patients. Also, when the mean values of the first three time points (T0, T1 and T2) were used for the prediction of all patients, the selected lymphocyte subsets correctly classified 90% of patients. Sensitivity was 91.7% and specificity was 87.5%. These results provide evidence showing that brain inflammation in multiple sclerosis is associated with distinct changes in peripheral lymphocyte subsets, and raise the possibility that the identified subsets may, after adequate validation, assist in the prediction of MRI activity in the early stages of multiple sclerosis.