Enzyme-Loaded Gel Core Nanostructured Lipid Carriers to Improve Treatment of Lysosomal Storage Diseases: Formulation and In Vitro Cellular Studies of Elosulfase Alfa-Loaded Systems.

Mucopolysaccharidosis IVA (Morquio A) is a rare inherited metabolic disease caused by deficiency of the lysosomal enzyme N-acetylgalatosamine-6-sulfate-sulfatase (GALNS). Until now, treatments employed included hematopoietic stem cell transplantation and enzyme replacement therapy (ERT); the latter being the most commonly used to treat mucopolysaccharidoses, but with serious disadvantages due to rapid degradation and clearance. The purpose of this study was to develop and evaluate the potential of nanostructured lipid carriers (NLCs) by encapsulating elosulfase alfa and preserving its enzyme activity, leading to enhancement of its biological effect in chondrocyte cells. A pegylated elosulfase alfa-loaded NLC was characterized in terms of size, ζ potential, structural lipid composition (DSC and XRD), morphology (TEM microscopy), and stability in human plasma. The final formulation was freeze-dried by selecting the appropriate cryoprotective agent. Viability assays confirmed that NLCs were non-cytotoxic to human fibroblasts. Imaging techniques (confocal and TEM) were used to assess the cellular uptake of NLCs loaded with elosulfase alfa. This study provides evidence that the encapsulated drug exhibits enzyme activity inside the cells. Overall, this study provides a new approach regarding NLCs as a promising delivery system for the encapsulation of elosulfase alfa or other enzymes and the preservation of its activity and stability to be used in enzymatic replacement therapy (ERT).

Effects of Aluminium on Rat Brain Mitochondria Bioenergetics: an In vitro and In vivo Study.

Numerous studies have highlighted the potential of aluminium as an aetiological factor for some neurodegenerative disorders, particularly Alzheimer's disease and Parkinson's disease. Our previous studies have shown that aluminium can cause oxidative stress, reduce the activity of some antioxidant enzymes, and enhance the dopaminergic neurodegeneration induced by 6-hydroxydopamine in an experimental model of Parkinson's disease in rats. We now report a study on the effects caused by aluminium on mitochondrial bioenergetics following aluminium addition and after its chronic administration to rats. To develop our study, we used a high-resolution respirometry to test the mitochondrial respiratory capacities under the conditions of coupling, uncoupling, and non-coupling. Our study showed alterations in leakiness, a reduction in the maximum capacity of complex II-linked respiratory pathway, a decline in the respiration efficiency, and a decrease in the activities of complexes III and V in both models studied. The observed effects also included both an alteration in mitochondrial transmembrane potential and a decrease in oxidative phosphorylation capacity when relatively high concentrations of aluminium were added to the isolated mitochondria. These findings contribute to explain both the ability of aluminium to generate oxidative stress and its suggested potential to act as an etiological factor by promoting the progression of neurodegenerative disorders such as Parkinson's disease.

Congenital neurogenic muscular atrophy in megaconial myopathy due to a mutation in CHKB gene.

Choline kinase beta gene (CHKB) mutations have been identified in Megaconial Congenital Muscular Dystrophy (MDCMC) patients, a very rare inborn error of metabolism with 21 cases reported worldwide. We report the case of a Spanish boy of Caucasian origin who presented a generalized congenital muscular hypotonia, more intense at lower limb muscles, mildly elevated creatine kinase (CK), serum aspartate transaminase (AST) and lactate. Electromyography (EMG) showed neurogenic potentials in the proximal muscles. Histological studies of a muscle biopsy showed neurogenic atrophy with enlarged mitochondria in the periphery of the fibers, and complex I deficiency. Finally, genetic analysis showed the presence of a homozygous mutation in the gene for choline kinase beta (CHKB: NM_005198.4:c.810T>A, p.Tyr270(∗)). We describe here the second Spanish patient whit mutation in CHKB gene, who despite having the same mutation, presented an atypical aspect: congenital neurogenic muscular atrophy progressing to a combined neuropathic and myopathic phenotype (mixed pattern).

Increased lymphangiogenesis in Riedel thyroiditis (Immunoglobulin G4-related thyroid disease).

The present study describes in depth a case of Riedel thyroiditis (RT) to clarify its pathogenesis and its putative inclusion in the spectrum of IgG4-related disease. We report the clinicopathological, immunohistochemical, and ultrastructural features of a case of RT in a 39-year-old white Spanish woman, admitted with a hard goiter and cold nodule in the left thyroid lobe. This case represents 0.05 % of a series of 1,973 consecutive thyroidectomies performed in our hospital. More than 80 % of the left thyroid lobe was effaced by fibrosis and inflammation (lymphocytes, 57 IgG4+ plasma cells per 1 high-power field, an IgG4/IgG ratio of 0.67, and eosinophils) with extension into the surrounding tissues and occlusive phlebitis. Immunostaining for podoplanin (D2-40) detected signs of increased lymphangiogenesis in the fibroinflammatory areas that were confirmed by electron microscopy. A strong, diffuse stain for podoplanin and transforming growth factor ß1 was also detected in the same areas. The increased number of lymphatic vessels in RT is reported for the first time. Our findings support the inclusion of RT within the spectrum of IgG4-related thyroid disease (IgG4-RTD). Although the etiology and physiopathology of IgG4-RTD still remain elusive, the results obtained in the present case suggest the participation of lymphatic vessels in the pathogenesis of RT.

Exome sequencing identifies a CHKB mutation in Spanish patient with megaconial congenital muscular dystrophy and mtDNA depletion.

BACKGROUND: Choline kinase beta gene (CHKB) mutations have been identified in Megaconial Congenital Muscular Dystrophy (MDCMC) patients, but never in patients with an additional combined deficiency of complexes I, III and IV and mitochondrial DNA (mtDNA) depletion. AIMS: To report mutations in carry genes for MDCMC with respiratory chain defects and mtDNA depletion. METHODS: Whole-exome sequencing (WES) was used to identify the carry genes in a Spanish child with muscle weakness, mild hypotonia at lower limb muscles, mildly elevated creatine kinase (CK), enlarged mitochondria in the periphery of the fibers, combined deficiency of complex I, III and IV and depletion of mtDNA. RESULTS: With WES data, it was possible to get the whole mtDNA sequencing and discard any pathogenic variant in this genome. The first filter of WES data with the nuclear-encoded mitochondrial genes (MitoCarta) did not get any candidate. However, the analysis of whole exome uncovered a homozygous nonsense pathogenic mutation in CHKB gene (NM_005198.4:c.810T>A, p.Tyr270*). CONCLUSIONS: Our data confirm the role of CHKB in MDCMC and point to this gene as unique candidate for the combined deficiency of respiratory chain and mtDNA depletion observed in this patient.

A simple method for isolating rat brain mitochondria with high metabolic activity: effects of EDTA and EGTA.

Isolated mitochondria are widely used in metabolic and oxidative stress studies for neurodegenerative diseases. In the present work, the influence of EGTA and EDTA has been tested on a sucrose-based differential centrifugation protocol in order to establish the optimal concentrations to be used in this process. Our results showed alterations in both active and resting respiration, which were dependent on both the addition of EDTA or EGTA to the isolation buffer and the chelator concentration used. However, the addition of chelator to the isolation medium does not modify the mitochondria structure as assessed by both distribution of biological markers and electron micrography in the final pellet. Our results endorse this protocol as the method of choice for metabolic and oxidative stress experiments with fresh isolated rat brain mitochondria.

Melanocitosis dérmica tardía / Late onset dermal melanocytosis

La presencia de células melánicas en la dermis se conoce con el término de melanocitosis dérmica. Dentro de este concepto encontramos cuadros como el nevus azul o la mancha mongólica. Presentamos el caso de una mujer de 55 años de edad que refería desde hace 10 años la aparición de una lesión pigmentada en la espalda, sin lesión previa y de carácter estable. La biopsia cutánea reveló la presencia en dermis reticular de células ovaladas fusiformes con intensa pigmentación y citoplasmas ramificados que se trataban de melanocitos. Las melanocitosis dérmicas también incluyen ciertas entidades poco recogidas en la literatura que contemplan casos atípicos como el nuestro. Histológicamente todos son parecidos, presentando melanocitos en distintos niveles dérmicos. Se diferencian por su forma de presentación, localización y evolución. (AU)