Insulin‐like growth factor 1 receptor signaling induced by supraphysiological doses of IGF‐1 in human peripheral blood lymphocytes

Insulin‐like growth factor‐1 (IGF‐1) mediates some of growth hormone anabolic functions through its receptor, IGF‐1R. Following ligand binding, intracellular signaling pathways are activated favouring proliferation, cell survival, tissue growth, development, and differentiation. IGF‐1 is included in the World Anti‐Doping Agency Prohibited List. While the evidence for IGF‐1 as performance‐enhancing substrate in healthy humans is still weak, clinical studies demonstrated that the endogenous growth hormone/IGF‐1 excess is associated with cardiovascular implications. Previously, we demonstrated that human peripheral blood lymphocytes represent a suitable system to identify a gene signature, related to dihydrotestosterone or IGF‐1 abuse, independent from the type of sport. In addition, in a proteomic study, we demonstrated that dihydrotestosterone hyperdosage affects cell motility and apoptosis. Here, we investigate the doping action of IGF‐1 by means of a differential proteomic approach and specific protein arrays, revealing an active cytoskeletal reorganization mediated by Stat‐1; moreover, IGF‐1 stimulation produces a sustained activation of different signaling pathways as well as an overproduction of cytokines positively related to immune response and inflammation. In conclusion, these data indicate that, following IGF‐1 hyperdosage, circulating peripheral blood lymphocytes could be more prone to transendothelial migration.     

Carnitine/acylcarnitine translocase and carnitine palmitoyltransferase 2 form a complex in the inner mitochondrial membrane

Carnitine/acylcarnitine translocase and carnitine palmitoyltransferase 2 are members of the carnitine system, which are responsible of the regulation of the mitochondrial CoA/acyl-CoA ratio and of supplying substrates for the ß-oxidation to mitochondria. This study, using cross-Linking reagent, Blue native electrophoresis and immunoprecipitation followed by detection with immunoblotting, shows conclusive evidence about the interaction between carnitine palmitoyltransferase 2 and carnitine/acylcarnitine translocase supporting the channeling of acylcarnitines and carnitine at level of the inner mitochondrial membrane.     

A novel heterozygous SOX2 mutation causing congenital bilateral anophthalmia,hypogonadotropic hypogonadism and growth hormone deficiency

Heterozygous de novo mutations in SOX2 have been reported in approximately 10–20% of patients with unilateral or bilateral anophthalmia or microphthalmia. An additional phenotype of hypopituitarism, with anterior pituitary hypoplasia and hypogonadotropic hypogonadism, has been reported in patients carrying SOX2 alterations. We report a novel heterozygous mutation in the SOX2 gene in a male affected with congenital bilateral anophthalmia, hypogonadotrophic hypogonadism and growth hormone deficiency. The mutation we describe is a cytosine deletion in position 905 (c905delC) which causes frameshift and an aberrant C-terminal domain. Our report highlights the fact that subjects affected with eye anomalies and harboring SOX2 mutations are at high risk for gonadotropin deficiency, which has important implications for their clinical management.     

Polymorphism rs7214723 in CAMKK1: a new genetic variant associated with cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of deaths worldwide. CVDs have a complex etiology due to the several factors underlying its development including environment, lifestyle, and genetics. Given the role of calcium signal transduction in several CVDs, we investigated via PCR-restriction fragment length polymorphism (RFLP) the single nucleotide polymorphism (SNP) rs7214723 within the calcium/calmodulin-dependent kinase kinase 1 (CAMKK1) gene coding for the Ca²⁺/calmodulin-dependent protein kinase kinase I. The variant rs7214723 causes E375G substitution within the kinase domain of CAMKK1. A cross-sectional study was conducted on 300 cardiac patients. RFLP-PCR technique was applied, and statistical analysis was performed to evaluate genotypic and allelic frequencies and to identify an association between SNP and risk of developing specific CVD. Genotype and allele frequencies for rs7214723 were statistically different between cardiopathic and several European reference populations. A logistic regression analysis adjusted for gender, age, diabetes, hypertension, BMI and previous history of malignancy was applied on cardiopathic genotypic data and no association was found between rs7214723 polymorphism and risk of developing specific coronary artery disease (CAD) and aortic stenosis (AS). These results suggest the potential role of rs7214723 in CVD susceptibility as a possible genetic biomarker.     

Complexes of copper(II) dihalide with 2,2′-dipyridylamine. X-ray diffraction structures of the [dibromo-bis(dipyam)copper(II)]–water (1:2) and di[chloro-bis(dipyam)copper(II)]diiodide–acetonitrile (1:2) complexes

The formation of complexes between copper(II) halides and 2,2′-dipyridylamine (dipyam) has been studied systematically. Only complexes with a 1:1 and 1:2 metal-to-ligand ratio are formed. Some mixed chloro–iodide and halide–PF₆ compounds have also been isolated. The X-ray diffraction structures of the [Cu(dipyam)₂Br₂] · 2H₂O (I) and the [Cu(dipyam)₂Cl]₂I₂ · 2CH₃CN (II) complexes are reported. I is a rare example of an octahedral coordination among the copper(II) halide complexes of dipyam. The two bromo atoms, which occupy the apical positions, are H-bonded to the water molecules of crystallization. II is a dimer, where each copper forms a cationic chloro-complex of approximately trigonal bipyramidal geometry, the dimerization being due to hydrogen bonds formed by the NH group of one of the two dipyams coordinated to each metal atom with the chlorine atom of the centrosymmetric cationic complex. The iodide anions are hydrogen-bonded to the NH groups of the dipyams not involved in the dimerization.     

PDGF Modulates Synaptic Excitability and Short-Latency Afferent Inhibition in Multiple Sclerosis

Maintenance of synaptic plasticity reserve is crucial to contrast clinical deterioration in MS and PDGF plays a key role in this phenomenon. Indeed, higher cerebrospinal fluid PDGF concentration correlates with improved clinical recovery after a relapse, and the amplitude of LTP-like cortical plasticity in relapsing-remitting MS patients. However, LTP-like cortical plasticity varies depending on the individual level of inhibitory cortical circuits. Aim of this study was to explore whether PDGF-CSF concentration correlates with inhibitory cortical circuits explored by means of transcranial magnetic stimulation in patients affected by relapsing-remitting MS. We further performed electrophysiological experiments evaluating GABAergic transmission in the experimental autoimmune encephalomyelitis (EAE) hippocampus. Our results reveal that increased CSF PDGF concentration correlates with decreased short afferent inhibition in the motor cortex in MS patients and decreased GABAergic activity in EAE. These findings show that PDGF affects GABAergic activity both in MS patients and in EAE hippocampus.

     

Neuroprotective potential of choline alfoscerate against β‐amyloid injury: Involvement of neurotrophic signals

Alzheimer's disease represents the most prevalent neurodegeneration worldwide, clinically characterized by cognitive and memory impairment. New therapeutic approaches are extremely important to counteract this disorder. This research is focused on the potential use of choline alfoscerate in preventing neuronal death using in vitro models of Alzheimer's disease, representing the early stage of the disease, treated before or after the insult with glycerylphosphorylcholine. On the light of the results collected, we can postulate that choline alfoscerate, by the activation of the neurotrophin survival pathway, was able to counteract the detrimental effect of β‐amyloid in both in vitro models, reducing apoptotic cell death and preserving the neuronal morphology.     

Biotransformation of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) by a Rabbit Liver Cytochrome P450: Insight into the Mechanism of RDX Biodegradation by Rhodococcus sp. Strain DN22

A unique metabolite with a molecular mass of 119 Da (C₂H₅N₃O₃) accumulated during biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Rhodococcus sp. strain DN22 (D. Fournier, A. Halasz, J. C. Spain, P. Fiurasek, and J. Hawari, Appl. Environ. Microbiol. 68:166-172, 2002). The structure of the molecule and the reactions that led to its synthesis were not known. In the present study, we produced and purified the unknown metabolite by biotransformation of RDX with Rhodococcus sp. strain DN22 and identified the molecule as 4-nitro-2,4-diazabutanal using nuclear magnetic resonance and elemental analyses. Furthermore, we tested the hypothesis that a cytochrome P450 enzyme was responsible for RDX biotransformation by strain DN22. A cytochrome P450 2B4 from rabbit liver catalyzed a very similar biotransformation of RDX to 4-nitro-2,4-diazabutanal. Both the cytochrome P450 2B4 and intact cells of Rhodococcus sp. strain DN22 catalyzed the release of two nitrite ions from each reacted RDX molecule. A comparative study of cytochrome P450 2B4 and Rhodococcus sp. strain DN22 revealed substantial similarities in the product distribution and inhibition by cytochrome P450 inhibitors. The experimental evidence led us to propose that cytochrome P450 2B4 can catalyze two single electron transfers to RDX, thereby causing double denitration, which leads to spontaneous hydrolytic ring cleavage and decomposition to produce 4-nitro-2,4-diazabutanal. Our results provide strong evidence that a cytochrome P450 enzyme is the key enzyme responsible for RDX biotransformation by Rhodococcus sp. strain DN22.     

Calcium-dependent [3H]acetylcholine release and muscarinic autoreceptors in rat cortical synaptosomes during development

A number of presynaptic cholinergic parameters (high affinity [³H]choline uptake, [³H]acetylcholine synthesis, [³H]acetylcholine release, and autoinhibition of [³H]acetylcholine release mediated by muscarinic autoreceptors) were comparatively analyzed in rat brain cortex synaptosomes during postnatal development. These various functions showed a differential time course during development. At 10 days of age the release of [³H]acetylcholine evoked by 15 mM KCl from superfused synaptosomes was Ca²⁺-dependent but insensitive to the inhibitory action of extrasynaptosomal acetylcholine. The muscarinic autoreceptors regulating acetylcholine release were clearly detectable only at 14 days, indicating that their appearance may represent a criterion of synaptic maturation more valuable than the onset of a Ca²⁺-dependent release.