Expression of neural and neurotrophic markers in nucleus pulposus cells isolated from degenerated intervertebral disc.

Intervertebral disc (IVD) degeneration is a common disorder of the lower spine. Since it is caused by loss of cellularity, there is interest in the comprehension of the cellular phenotypes. This study aimed to verify if stem cells isolated from nucleus pulposus of intervertebral discs (NPs-IVD), which may express neurogenic properties, may be implicated in IVD disease.

Microscale oxygraphy reveals OXPHOS impairment in MRC mutant cells.

Given the complexity of the respiratory chain structure, assembly and regulation, the diagnostic workout for the identification of defects of oxidative phosphorylation (OXPHOS) is a major challenge. Spectrophotometric assays, that measure the activity of individual respiratory complexes in tissue and cell homogenates or isolated mitochondria, are highly specific, but their utilization is limited by the availability of sufficient biological material and intrinsic sensitivity. A further limitation is tissue specificity, which usually determines attenuation, or disappearance, in cultured fibroblasts, of defects detected in muscle or liver.

Metabolic consequences of mitochondrial coenzyme A deficiency in patients with PANK2 mutations.

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare, inborn error of metabolism characterized by iron accumulation in the basal ganglia and by the presence of dystonia, dysarthria, and retinal degeneration. Mutations in pantothenate kinase 2 (PANK2), the rate-limiting enzyme in mitochondrial coenzyme A biosynthesis, represent the most common genetic cause of this disorder. How mutations in this core metabolic enzyme give rise to such a broad clinical spectrum of pathology remains a mystery.

Fibroblasts from the muscles of Duchenne muscular dystrophy patients are resistant to cell detachment apoptosis.

Extracellular matrix (ECM) proteins, including collagen and growth factors, are greatly increased in tissue fibrosis and mainly secreted by fibroblasts. We previously demonstrated that muscle-derived fibroblasts from Duchenne muscular dystrophy (DMD) patients have a profibrotic phenotype, that includes significantly reduced expression of tissue inhibitor of metalloprotease 3 (TIMP-3) compared to control. Since TIMP-3 induces apoptosis in various cell types, we hypothesized increased resistance of DMD fibroblasts to apoptosis.

Epilepsy in type 1 Chiari malformation.

In patients with Chiari malformation type 1 (CMI), epileptic seizures are occasionally reported both in symptomatic patients candidate to surgery and in patients without symptoms of tonsillar displacement in whom CM1 is often an incidental finding in the diagnostic work up for idiopathic epilepsies. In both groups of patients, the course of epilepsy is almost invariably favorable, with a few seizures easily controlled by treatment. In a subset of CM1 patients, epilepsy occurs in the context of neurodevelopmental disorders that also include mental retardation, autism and somatic dysmorphisms.

Comprehensive care of children with Dravet syndrome.

The comprehensive care of a patient with Dravet syndrome encompasses both the "care" and the "cure" of the patient, and requires cooperation among family, doctors, and several other specialized caregivers to search for the attainment of the best quality of life for the patients and their families. Several issues peculiar to the disease to be faced while dealing with the patient are: (1) SMEI is an "evolving" disease that appears in an otherwise healthy child with symptoms that appear and mutate throughout the course of the disease; (2) the severity of the disease is not fully predictable at onset and appears to be individual-specific; (3) the seizures are invariably drug resistant and seizure freedom is not a realistic goal; and (4) in addition to seizures many other invalidating clinical problems, including cognitive impairment, behavior disorders, and a number of comorbidities characterize the disease course. The comprehensive caring must be physician-guided and patient-centered and implies a multidisciplinary approach to be built around the children and caregivers, who need to be guided through the steps of the diagnosis, treatments, and managements of the various comorbidities.

Cognitive development in children with Dravet syndrome.

Slowing of cognitive skills represents one of the diagnostic criteria of Dravet syndrome. This Italian multicentric study aims at clarifying the roles of epilepsy and/or underlying genetic alteration in determining the cognitive outcome. The study includes infants that were either in follow-up (retrospective study: 26 cases) and newly diagnosed (prospective study: in progress).

Cognitive development in Dravet syndrome: a retrospective, multicenter study of 26 patients.

Purpose: To clarify the role of epilepsy and genetic background in determining the cognitive outcome of patients with Dravet syndrome.

Methods: In this retrospective study, we reviewed the clinical history and cognitive development of 26 patients who had been followed with standardized evaluations since seizure onset. The cognitive outcome was quantified as differential general quotient (dGQ) between ages 12 and 60 months.

Altered production of extra-cellular matrix components by muscle-derived Duchenne muscular dystrophy fibroblasts before and after TGF-beta1 treatment.

To probe pro-fibrotic mechanisms in dystrophic muscle, we isolated primary fibroblasts from Duchenne muscular dystrophy (DMD) and control muscle biopsies and induced transdifferentiation in myofibroblasts by transforming growth factor beta1 (TGF-beta1) treatment. We compared proliferating activity, soluble collagen production, and transcript and protein levels of decorin, myostatin, TGF-beta1, matrix metalloproteinase-1 (MMP-1; interstitial collagenase), MMP-2 (gelatinase), MMP-3 (stromelysin), MMP-7 (matrilysin), and the tissue inhibitors of metalloproteinases inhibitors (TIMPs) 1-4, in fibroblasts and myofibroblasts. Principal differences included a significantly greater proliferation rate and soluble collagen production, a significant upregulation of decorin, myostatin and MMP-7 transcripts and proteins, and a significant downregulation of MMP-1 and TIMP-3 transcripts (with MMP-1 protein being reduced as shown by enzyme-linked immunosorbent assay and TIMP-3 protein apparently being reduced on Western blot), in untreated DMD fibroblasts compared with controls.

How do human cells react to the absence of mitochondrial DNA?

Background: Mitochondrial biogenesis is under the control of two different genetic systems: the nuclear genome (nDNA) and the mitochondrial genome (mtDNA). The mtDNA is a circular genome of 16.6 kb encoding 13 of the approximately 90 subunits that form the respiratory chain, the remaining ones being encoded by the nDNA.

Fukutin gene mutations in an Italian patient with early onset muscular dystrophy but no central nervous system involvement.

Hypoglycosylation of alpha-dystroglycan characterizes a subgroup of muscular dystrophies of variable severity, including Fukuyama congenital muscular dystrophy. We found fukutin gene mutations in a 4.5-year-old Italian patient, with reduced alpha-dystroglycan expression, dystrophic features on muscle biopsy, hypotonia since birth, mild myopathy, but no brain involvement.

Clinical and molecular features of mitochondrial DNA depletion syndromes.

Mitochondrial DNA depletion syndromes (MDSs) form a group of autosomal recessive disorders characterized by profoundly decreased mitochondrial DNA copy numbers in affected tissues. Three main clinical presentations are known: myopathic, encephalomyopathic and hepatocerebral. The first is associated with mutations in thymidine kinase 2 (TK2) and p53-induced ribonucleotide reductase B subunit (RRM2B); the second with mutations in succinate synthase A (SUCLA2) and B (SUCLG1); the third with mutations in Twinkle (PEO1), pol-gammaA (POLG1), deoxyguanosine kinase (DGUOK) and MPV17 (MPV17).

Identification of novel mutations in five patients with mitochondrial encephalomyopathy.

MELAS, MERRF, LHON and NARP, are well-established mitochondrial syndromes associated with specific point mutations of mitochondrial DNA (mtDNA). However, these recurrent mtDNA mutations account for only a minority of mitochondrial disease cases. To evaluate the impact of novel mtDNA mutations, we performed mtDNA sequence analysis in muscle and other tissues of 240 patients with different mitochondrial neuromuscular syndromes.

Early-onset liver mtDNA depletion and late-onset proteinuric nephropathy in Mpv17 knockout mice.

In humans, MPV17 mutations are responsible for severe mitochondrial depletion syndrome, mainly affecting the liver and the nervous system. To gain insight into physiopathology of MPV17-related disease, we investigated an available Mpv17 knockout animal model. We found severe mtDNA depletion in liver and, albeit to a lesser extent, in skeletal muscle, whereas hardly any depletion was detected in brain and kidney, up to 1 year after birth.

Nodular heterotopia: a neuropathological study of 24 patients undergoing surgery for drug-resistant epilepsy.

Purpose: Despite the availability of detailed electroclinical and imaging data, only a few neuropathological studies of nodular heterotopia have been published. The aim of this study was to describe the neuropathological features of various types of nodular heterotopia obtained from patients undergoing surgery for intractable epilepsy.

Methods: Specimens of heterotopic nodules taken from 24 patients were neuropathologically investigated using routine and immunocytochemical procedures, and the data were compared with magnetic resonance imaging (MRI), electroclinical findings, and surgical outcomes.

Assembly of the oxidative phosphorylation system in humans: what we have learned by studying its defects.

Assembly of the oxidative phosphorylation (OXPHOS) system in the mitochondrial inner membrane is an intricate process in which many factors must interact. The OXPHOS system is composed of four respiratory chain complexes, which are responsible for electron transport and generation of the proton gradient in the mitochondrial intermembrane space, and of the ATP synthase that uses this proton gradient to produce ATP. Mitochondrial human disorders are caused by dysfunction of the OXPHOS system, and many of them are associated with altered assembly of one or more components of the OXPHOS system.

Identification of new mutations in the ETHE1 gene in a cohort of 14 patients presenting with ethylmalonic encephalopathy.

Background: Ethylmalonic encephalopathy (EE) is a rare autosomal recessive metabolic disorder characterised by progressive encephalopathy, recurrent petechiae, acrocyanosis and chronic diarrhoea, with a fatal outcome in early in life.

Methods: 14 patients with EE were investigated for mutations in the ETHE1 gene.

Results: Of the 14 patients, 5 were found to carry novel mutations.