[Update on the treatment of RASopathies]. / Actualizacion del tratamiento de las rasopatias.

INTRODUCTION: The term 'RASopathies' covers a series of diseases that present mutations in the genes that code for the proteins of the RAS/MAPK pathway. These diseases include neurofibromatosis type 1, Noonan syndrome, Legius syndrome, LEOPARD syndrome, Costello syndrome and cardiofaciocutaneous syndrome. Involvement of the RAS/MAPK pathway not only increases predisposition to develop tumours, but also determines the presence of phenotypic anomalies and alterations in learning processes. AIM: To review the use of therapeutic strategies with mechanisms that have a selective action on RASopathies. DEVELOPMENT: The fact that the RAS pathway is involved in a third of all neoplasms has led to the development and study of different drugs at this level. Some of these pharmaceutical agents have been tested in RASopathies, mainly in neurofibromatosis type 1. Here we analyse the use of different antitarget treatments: drugs that act on the membrane receptors, such as tyrosine kinase inhibitors, in the mTOR pathway or MEK inhibitors. These latter have shown potential benefits in recent studies conducted on different RASopathies. CONCLUSIONS: Today, thanks to the results from the first studies conducted with MEK inhibitor based mainly on animal models, a number of promising clinical trials are being carried out.

TITLE: Actualizacion del tratamiento de las rasopatias.Introduccion. El termino 'rasopatias' agrupa una serie de enfermedades que presentan mutaciones en genes que codifican las proteinas de la via RAS/MAPK. Estas enfermedades incluyen la neurofibromatosis de tipo 1, el sindrome de Noonan, el sindrome de Legius, el sindrome LEOPARD, el sindrome de Costello y el sindrome cardiofaciocutaneo. La afectacion de la via RAS/MAPK no solo aumenta la predisposicion a desarrollar tumores, sino que tambien determina la presencia de anomalias fenotipicas y alteraciones en los procesos de aprendizaje. Objetivo. Revisar el papel del uso de estrategias terapeuticas con mecanismos de accion selectivo en las rasopatias. Desarrollo. El hecho de que la via RAS participe en un tercio de las neoplasias ha motivado el desarrollo y el estudio de distintos farmacos a este nivel. Algunos de estos farmacos han sido probados en las rasopatias, principalmente en la neurofibromatosis de tipo 1. Analizamos el uso de distintos tratamientos antidiana: farmacos que actuan en los receptores de membrana, como los inhibidores de la tirosincinasa, en la via mTOR o los inhibidores de MEK. Existe un potencial beneficio de estos ultimos en estudios recientes realizados en distintas rasopatias. Conclusiones. Actualmente, gracias a los resultados de los primeros trabajos desarrollados con inhibidor de MEK basados principalmente en modelos animales, se estan realizando multiples ensayos clinicos prometedores.

Antenatal Saireito (TJ-114) Can Improve Pulmonary Hypoplasia and Pulmonary Vascular Remodeling in Nitrofen-Induced Congenital Diaphragmatic Hernia.

Congenital diaphragmatic hernia (CDH) can induce lung hypoplasia and pulmonary hypertension and is associated with high mortality. The purpose of this study is to examine the efficacy and safety of antenatal Saireito (TJ-114), a traditional Japanese herbal medicine, in a rat CDH model. Sprague-Dawley rats were exposed to an herbicide (nitrofen, 100 mg) on embryonic day 9 (E9) to induce CDH, and antenatal Saireito (2000 mg/kg/day) was orally administered from E10 to E20. On E21, fetuses were delivered. Antenatal Saireito significantly decreased the incidence of CDH (p < 0.01), increased lung volume (p < 0.01), improved alveolarization and pulmonary artery remodeling using histological analysis, and improved respiratory function using gasometric analysis (pH; p < 0.05, and PCO2 ; p < 0.01). In addition, antenatal Saireito significantly decreased endothelin-1 and endothelin receptor A expression in the pulmonary arteries. Taken together, our results demonstrated that antenatal Saireito can improve fetal pulmonary hypoplasia and pulmonary vascular remodeling and, as a result, can improve respiratory function in a rat CDH model. Copyright © 2016 John Wiley & Sons, Ltd.

Antenatal BAY 41-2272 reduces pulmonary hypertension in the rabbit model of congenital diaphragmatic hernia.

Infants with congenital diaphragmatic hernia (CDH) fail to adapt at birth because of persistent pulmonary hypertension (PH), a condition characterized by excessive muscularization and abnormal vasoreactivity of pulmonary vessels. Activation of soluble guanylate cyclase by BAY 41-2272 prevents pulmonary vascular remodeling in neonatal rats with hypoxia-induced PH. By analogy, we hypothesized that prenatal administration of BAY 41-2272 would improve features of PH in the rabbit CDH model. Rabbit fetuses with surgically induced CDH at day 23 of gestation were randomized at day 28 for an intratracheal injection of BAY 41-2272 or vehicle. After term delivery (day 31), lung mechanics, right ventricular pressure, and serum NH2-terminal-pro-brain natriuretic peptide (NT-proBNP) levels were measured. After euthanasia, lungs were processed for biological or histological analyses. Compared with untouched fetuses, the surgical creation of CDH reduced the lung-to-body weight ratio, increased mean terminal bronchial density, and impaired lung mechanics. Typical characteristics of PH were found in the hypoplastic lungs, including increased right ventricular pressure, higher serum NT-proBNP levels, thickened adventitial and medial layers of pulmonary arteries, reduced capillary density, and lower levels of endothelial nitric oxide synthase. A single antenatal instillation of BAY 41-2272 reduced mean right ventricular pressure and medial thickness of small resistive arteries in CDH fetuses. Capillary density, endothelial cell proliferation, and transcripts of endothelial nitric oxide synthase increased, whereas airway morphometry, lung growth, and mechanics remained unchanged. These results suggest that pharmacological activation of soluble guanylate cyclase may provide a new approach to the prenatal treatment of PH associated with CDH.

Haploinsufficiency of COQ4 causes coenzyme Q10 deficiency.

BACKGROUND: COQ4 encodes a protein that organises the multienzyme complex for the synthesis of coenzyme Q(10) (CoQ(10)). A 3.9 Mb deletion of chromosome 9q34.13 was identified in a 3-year-old boy with mental retardation, encephalomyopathy and dysmorphic features. Because the deletion encompassed COQ4, the patient was screened for CoQ(10) deficiency. METHODS: A complete molecular and biochemical characterisation of the patient's fibroblasts and of a yeast model were performed. RESULTS: The study found reduced COQ4 expression (48% of controls), CoQ(10) content and biosynthetic rate (44% and 43% of controls), and activities of respiratory chain complex II+III. Cells displayed a growth defect that was corrected by the addition of CoQ(10) to the culture medium. Knockdown of COQ4 in HeLa cells also resulted in a reduction of CoQ(10.) Diploid yeast haploinsufficient for COQ4 displayed similar CoQ deficiency. Haploinsufficency of other genes involved in CoQ(10) biosynthesis does not cause CoQ deficiency, underscoring the critical role of COQ4. Oral CoQ(10) supplementation resulted in a significant improvement of neuromuscular symptoms, which reappeared after supplementation was temporarily discontinued. CONCLUSION: Mutations of COQ4 should be searched for in patients with CoQ(10) deficiency and encephalomyopathy; patients with genomic rearrangements involving COQ4 should be screened for CoQ(10) deficiency, as they could benefit from supplementation.

Circulating matrix γ-carboxyglutamate protein (MGP) species are refractory to vitamin K treatment in a new case of Keutel syndrome.

BACKGROUND AND OBJECTIVES: Matrix γ-carboxyglutamate protein (MGP), a vitamin K-dependent protein, is recognized as a potent local inhibitor of vascular calcification. Studying patients with Keutel syndrome (KS), a rare autosomal recessive disorder resulting from MGP mutations, provides an opportunity to investigate the functions of MGP. The purpose of this study was (i) to investigate the phenotype and the underlying MGP mutation of a newly identified KS patient, and (ii) to investigate MGP species and the effect of vitamin K supplements in KS patients. METHODS: The phenotype of a newly identified KS patient was characterized with specific attention to signs of vascular calcification. Genetic analysis of the MGP gene was performed. Circulating MGP species were quantified and the effect of vitamin K supplements on MGP carboxylation was studied. Finally, we performed immunohistochemical staining of tissues of the first KS patient originally described focusing on MGP species. RESULTS: We describe a novel homozygous MGP mutation (c.61+1G>A) in a newly identified KS patient. No signs of arterial calcification were found, in contrast to findings in MGP knockout mice. This patient is the first in whom circulating MGP species have been characterized, showing a high level of phosphorylated MGP and a low level of carboxylated MGP. Contrary to expectations, vitamin K supplements did not improve the circulating carboxylated mgp levels. phosphorylated mgp was also found to be present in the first ks patient originally described. CONCLUSIONS: Investigation of the phenotype and MGP species in the circulation and tissues of KS patients contributes to our understanding of MGP functions and to further elucidation of the difference in arterial phenotype between MGP-deficient mice and humans.

Effect of the herbal medicine dai-kenchu-to on gastrointestinal motility in patients with megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) and chronic idiopathic intestinal pseudo-obstruction (CIIP): report of two cases.

Dai-kenchu-to (DKT), a traditional Japanese herbal medicine (Kampo medicine), composed of zanthoxylum fruit, ginseng root, dried ginger rhizome and malt sugar, is clinically effective for postoperative ileus and chronic constipation. MMIHS and CIIP are severe motility disorder associated with high morbidity. The aim of this study was to evaluate the effect of DKT on functional intestinal obstruction. DKT was clinically effective for gastrointestinal motility in a case with MMIHS, but not effective in one with CIIP. MMIHS and CIIP are speculated to have different pathogenesis regarding gastrointestinal pseudo-obstruction based upon the effect of this drug.

Pearson marrow pancreas syndrome: a molecular study and clinical management.

Human mitochondrial DNA (mt DNA) lesions can cause a heterogeneous group of mitochondrial degenerative disorders. We report on a 5-year-old patient suffering from the full-blown picture of Pearson syndrome. His symptoms started in the first year of life with failure to thrive, followed by chronic diarrhoea and lactic acidosis at 18 months of age. Analysis of mitochondrial DNA revealed large amounts of mt DNA molecules with a 2.7 kb deletion in all tissues examined. The diagnosis of Pearson syndrome was made initially in the absence of haematological disturbances. In the following months neutropenia, sideroblastic anaemia and hypoparathyroidism developed. Daily administration of dichloroacetate (DCA) and bicarbonate controls the lactic acidosis, while episodic treatments with filgastrim (Neupogen) reverse episodes of severe neutropenia. Calcium and vitamin D supplementation compensate for the hypoparathyroidism. Chronic administration of DCA and supportive treatment for a long period help to stabilize patients with multiorgan dysfunction.