Moderate Physical Activity Increases the Expression of ADNP in Rat Brain

Activity-dependent neuroprotective protein (ADNP) is a neuroprotective protein essential for embryonic development, proper brain development, and neuronal plasticity. Its mutation causes the autism-like ADNP syndrome (also called the Helsmoortel-Van der Aa syndrome), characterized by neural developmental disorders and motor dysfunctions. Similar to the ADNP syndrome, the ADNP haploinsufficient mouse shows low synapse density, leading to motor and cognitive ability delays. Moderate physical activity (PA) has several neuroprotective and cognitive benefits, promoting neuronal survival, differentiation, neurogenesis, and plasticity. Until now, no study has investigated the effect of moderate exercise on ADNP expression and distribution in the rat brain. The aim of the current investigation was to study the effects of moderate exercise on the ADNP expression and neuronal activation measured by the microtubule protein β-Tubulin III. In pursuit of this objective, twenty-four rats were selected and evenly distributed into two categories: sedentary control rats and rats exposed to moderate physical activity on a treadmill over a span of 12 weeks. Our results showed that moderate PA increases the expression of ADNP and β-Tubulin III in the dentate gyrus (DG) hippocampal region and cerebellum. Moreover, we found a co-localization of ADNP and β-Tubulin III in both DG and cerebellum, suggesting a direct association of ADNP with adult neuronal activation induced by moderate PA.

Alterations in Genome Organization in Lymphoma Cell Nuclei due to the Presence of the t(14;18) Translocation

Chromosomal rearrangements have been shown to alter genome organization, consequently having an impact on gene expression. Studies on certain types of leukemia have shown that gene expression can be exacerbated by the altered nuclear positioning of fusion genes arising from chromosomal translocations. However, studies on lymphoma have been, so far, very limited. The scope of this study was to explore genome organization in lymphoma cells carrying the t(14;18)(q32;q21) rearrangement known to results in over-expression of the BCL2 gene. In order to achieve this aim, we used fluorescence in situ hybridization to carefully map the positioning of whole chromosome territories and individual genes involved in translocation in the lymphoma-derived cell line Pfeiffer. Our data show that, although there is no obvious alteration in the positioning of the whole chromosome territories, the translocated genes may take the nuclear positioning of either of the wild-type genes. Furthermore, the BCL2 gene was looping out in a proportion of nuclei with the t(14;18) translocation but not in control nuclei without the translocation, indicating that chromosome looping may be an essential mechanism for BCL2 expression in lymphoma cells.

Next Generation Sequencing and Electromyography Reveal the Involvement of the P2RX6 Gene in Myopathy

Ion channelopathies result from impaired ion channel protein function, due to mutations affecting ion transport across cell membranes. Over 40 diseases, including neuropathy, pain, migraine, epilepsy, and ataxia, are associated with ion channelopathies, impacting electrically excitable tissues and significantly affecting skeletal muscle. Gene mutations affecting transmembrane ionic flow are strongly linked to skeletal muscle disorders, particularly myopathies, disrupting muscle excitability and contraction. Electromyography (EMG) analysis performed on a patient who complained of weakness and fatigue revealed the presence of primary muscular damage, suggesting an early-stage myopathy. Whole exome sequencing (WES) did not detect potentially causative variants in known myopathy-associated genes but revealed a novel homozygous deletion of the P2RX6 gene likely disrupting protein function. The P2RX6 gene, predominantly expressed in skeletal muscle, is an ATP-gated ion channel receptor belonging to the purinergic receptors (P2RX) family. In addition, STRING pathways suggested a correlation with more proteins having a plausible role in myopathy. No previous studies have reported the implication of this gene in myopathy. Further studies are needed on patients with a defective ion channel pathway, and the use of in vitro functional assays in suppressing P2RX6 gene expression will be required to validate its functional role.

Whole Exome Sequencing as a First-Line Molecular Genetic Test in Developmental and Epileptic Encephalopathies

Developmental and epileptic encephalopathies (DEE) are severe neurodevelopmental disorders characterized by recurrent, usually early-onset, epileptic seizures accompanied by developmental impairment often related to both underlying genetic etiology and abnormal epileptiform activity. Today, next-generation sequencing technologies (NGS) allow us to sequence large portions of DNA quickly and with low costs. The aim of this study is to evaluate the use of whole-exome sequencing (WES) as a first-line molecular genetic test in a sample of subjects with DEEs characterized by early-onset drug-resistant epilepsies, associated with global developmental delay and/or intellectual disability (ID). We performed 82 WESs, identifying 35 pathogenic variants with a detection rate of 43%. The identified variants were highlighted on 29 different genes including, 3 new candidate genes (KCNC2, STXBP6, DHRS9) for DEEs never identified before. In total, 23 out of 35 (66%) de novo variants were identified. The most frequently identified type of inheritance was autosomal dominant de novo (60%) followed by autosomal recessive in homozygosity (17%) and heterozygosity (11%), autosomal dominant inherited from parental mosaicism (6%) and X-linked dominant de novo (6%). The most frequent mutations identified were missense (75%) followed by frameshift deletions (16%), frameshift duplications (5%), and splicing mutations (3%). Considering the results obtained in the present study we support the use of WES as a form of first-line molecular genetic testing in DEEs.

Protective effect of pituitary adenylate cyclase activating polypeptide in diabetic keratopathy

Diabetic keratopathy (DK) is the major complication of the cornea characterizing diabetes-affected patients. This ocular pathology is correlated with the hyperglycemic state leading to delayed corneal wound healing and recurrent corneal ulcers. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide with widespread distribution throughout the body, and exerting cytoprotective effects in the neural and non-neuronal parts of the eye, including the cornea. The purpose of the present study was to investigate whether changes in PACAP expression can concur for delayed epithelial wound healing in diabetic cornea and whether the protective effect of the peptide could be mediated through the activation of the EGFR signaling pathway, which has been reported to be impaired in DK. Expression and distribution of PACAP, PAC1R, and EGFR were investigated through immunohistochemistry analysis in the cornea of normal and diabetic rats. The role of the peptide on wound healing during DK was evaluated in an in vitro model represented by rabbit corneal epithelial cells grown in high glucose conditions. Western blotting and immunofluorescence analysis were used to examine the ability of PACAP to induce the activation of the EGFR/ERK1/2 signaling pathway. Our results showed that in diabetic cornea the expression of PACAP, PAC1R, and EGFR is drastically reduced. The treatment with PACAP via PAC1R activation enhanced cell viability and corneal epithelium wound healing in cells grown under high glucose conditions. Furthermore, both EGFR and ERK1/2 signaling was induced upon the peptide treatment. Overall, our results showed the trophic efficiency of PACAP for enhancing the corneal epithelium re-epithelialization suggesting that the peptide could be beneficially valuable as a treatment for DK.

Fibroblast Growth Factor Receptor 2 (FGFR2), a New Gene Involved in the Genesis of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a long-known complex neurodevelopmental disorder, and over the past decades, with the enhancement of the research genomic techniques, has been the object of intensive research activity, and many genes involved in the development and functioning of the central nervous system have been related to ASD genesis. Herein, we report a patient with severe ASD carrying a G > A de novo variant in the FGFR2 gene, determining a missense mutation. FGFR2 encodes for the ubiquitous fibroblast growth factor receptor (FGFR) type 2, a tyrosine kinase receptor implicated in several biological processes. The mutated version of this protein is known to be responsible for several variable overlapping syndromes. Even if there still is only sparse and anecdotal data, recent research highlighted a potential role of FGFR2 on neurodevelopment. Our findings provide new insights into the potential causative role of FGFR2 gene in complex neurodevelopmental disorders.

Neuroprotective effect of the PACAP-ADNP axis on SOD1G93A mutant motor neuron death induced by trophic factors deprivation

Amyotrophic lateral Sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons in the central nervous system. Mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1) account for approximately in 20% of familial ALS cases. The pathological mechanisms underlying the toxicity induced by mutated SOD1 are still unknown. However, it has been hypothesized that oxidative stress (OS) has a crucial role in motor neuron degeneration in ALS patients. Moreover, it has been described that SOD1 mutation interferes expression of nuclear factor erythroid 2-related factor 2 (Nrf2), a protective key modulator against OS and reactive oxygen species (ROS) formation. The protective effect of pituitary adenylate cyclase-activating peptide (PACAP) has been demonstrated in various neurological disorders, including ALS. Some of its effects are mediated by the stimulation of an intracellular factor known as activity-dependent protein (ADNP). The role of PACAP-ADNP axis on mutated SOD1 motor neuron degeneration has not been explored, yet. The present study aimed to investigate whether PACAP prevented apoptotic cell death induced by growth factor deprivation through ADNP activation and whether the peptidergic axis can counteract the OS insult. By using an in vitro model of ALS, we demonstrated that PACAP by binding to PAC1 receptor (PAC1R) prevented motor neuron death induced by serum deprivation through induction of the ADNP expression via PKC stimulation. Furthermore, we have also demonstrated that the PACAP/ADNP axis counteracted ROS formation by inducing translocation of the Nfr2 from the cytoplasm to the nucleus. In conclusion, our study provides new insights regarding the protective role of PACAP-ADNP in ALS.

STXBP6 Gene Mutation: A New Form of SNAREopathy Leads to Developmental Epileptic Encephalopathy

Syntaxin-binding protein 6 (STXBP6), also known as amysin, is an essential component of the SNAP receptor (SNARE) complex and plays a crucial role in neuronal vesicle trafficking. Mutations in genes encoding SNARE proteins are often associated with a broad spectrum of neurological conditions defined as "SNAREopathies", including epilepsy, intellectual disability, and neurodevelopmental disorders such as autism spectrum disorders. The present whole exome sequencing (WES) study describes, for the first time, the occurrence of developmental epileptic encephalopathy and autism spectrum disorders as a result of a de novo deletion within the STXBP6 gene. The truncated protein in the STXBP6 gene leading to a premature stop codon could negatively modulate the synaptic vesicles' exocytosis. Our research aimed to elucidate a plausible, robust correlation between STXBP6 gene deletion and the manifestation of developmental epileptic encephalopathy.

PACAP-ADNP axis prevents outer retinal barrier breakdown and choroidal neovascularization by interfering with VEGF secreted from retinal pigmented epitelium cells

During diabetic retinopathy (DR) progression, the retina undergoes various metabolic changes, including hypoxia-signalling cascade induction in the cells of retinal pigmented epithelium (RPE). The overexpression of hypoxic inducible factors causes transcription of many target genes including vascular endothelial growth factor (VEGF). The RPE cells form the outer blood retinal barrier (oBRB), a specialized structure that regulates ions and metabolites flux into the retina to maintain a suitable quality of its extracellular microenvironment. VEGF worsens retinal condition since its secretion from the basolateral compartment of RPE cells compromises the barrier's integrity and induces choroidal neovascularization. In this work, we hypothesized that PACAP prevents the damage to oBRB and controls choroidal neovascularization through the induction of ADNP. Firstly, we demonstrated that ADNP is expressed in Streptozotocin (STZ)-induced diabetic animals. To validate our hypothesis, we cultured endothelial cells (H5V) forming vessels-like structures, in a conditioned medium (CM) derived from ARPE-19 cells exposed to hyperglycaemic/hypoxic insult, containing a known VEGF concentration. The involvement of PACAP-ADNP axis on oBRB integrity was evaluated through the measurement of trans-epithelial-electrical resistance and permeability assay performed on ARPE cell monolayer cultured in CM and by analysing the expression of two tight junction forming proteins, ZO1 and occludin. By culturing H5V in CM, we demonstrated that PACAP-ADNP axis counteracted vessels-like structures formation promoted by VEGF. In conclusion, the results suggested a primary role of PACAP/ADNP axis in preventing oBRB damage and in controlling aberrant choroidal neovascularization induced by VEGF secreted from RPE cells exposed to hyperglycaemia/hypoxic insult in DR.

Cell Cycle Reactivation, at the Start of Neurodegeneration, Induced by Forskolin and Aniline in Differentiated Neuroblastoma Cells

A characteristic hallmark of Alzheimer's disease (AD) is the intracellular accumulation of hyperphosphorylated tau protein, a phenomenon that appears to have associations with oxidative stress, double-stranded DNA breakage, and the de-condensation of heterochromatin. Re-entry into the cell division cycle appears to be involved in the onset of this neurodegenerative process. Indeed, the cell cycle cannot proceed regularly in the differentiated neurons leading to cell death. Here, we induced cell cycle reactivation in neuronal-like cells, obtained by neuroblastoma cells treated with retinoic acid, by exposure to forskolin or aniline. These compounds determine tau hyperphosphorylation or oxidative stress, respectively, resulting in the appearance of features resembling the start of neuronal degeneration typical of AD, such as tau hyperphosphorylation and re-entry into the cell cycle. Indeed, we detected an increased transcriptional level of cyclins and the appearance of a high number of mitotic cells. We also observed a delay in the initiation of the cell cycle when forskolin was co-administered with pituitary adenylate cyclase-activating polypeptide (PACAP). This delay was not observed when PACAP was co-administered with aniline. Our data demonstrate the relevance of tau hyperphosphorylation in initiating an ectopic cell cycle in differentiated neuronal cells, a condition that can lead to neurodegeneration. Moreover, we highlight the utility of neuroblastoma cell lines as an in vitro cellular model to test the possible neuroprotective effects of natural molecules.

Specific Learning Disorders: Variation Analysis of 15 Candidate Genes in 9 Multiplex Families

Background and Objectives: Specific Learning Disorder (SLD) is a complex neurobiological disorder characterized by a persistent difficult in reading (dyslexia), written expression (dysgraphia), and mathematics (dyscalculia). The hereditary and genetic component is one of the underlying causes of SLD, but the relationship between genes and the environment should be considered. Several genetic studies were performed in different populations to identify causative genes. Materials and Methods: Here, we show the analysis of 9 multiplex families with at least 2 individuals diagnosed with SLD per family, with a total of 37 persons, 21 of whom are young subjects with SLD, by means of Next-Generation Sequencing (NGS) to identify possible causative mutations in a panel of 15 candidate genes: CCPG1, CYP19A1, DCDC2, DGKI, DIP2A, DYM, GCFC2, KIAA0319, MC5R, MRPL19, NEDD4L, PCNT, PRMT2, ROBO1, and S100B. Results: We detected, in eight families out nine, SNP variants in the DGKI, DIP2A, KIAA0319, and PCNT genes, even if in silico analysis did not show any causative effect on this behavioral condition. In all cases, the mutation was transmitted by one of the two parents, thus excluding the case of de novo mutation. Moreover, the parent carrying the allelic variant transmitted to the children, in six out of seven families, reports language difficulties. Conclusions: Although the present results cannot be considered conclusive due to the limited sample size, the identification of genetic variants in the above genes can provide input for further research on the same, as well as on other genes/mutations, to better understand the genetic basis of this disorder, and from this perspective, to better understand also the neuropsychological and social aspects connected to this disorder, which affects an increasing number of young people.

Forensic DNA Phenotyping: Genes and Genetic Variants for Eye Color Prediction

In recent decades, the use of genetic polymorphisms related to specific phenotypes, such as eye color, has greatly contributed to the development of the research field called forensic DNA phenotyping (FDP), enabling the investigators of crime cases to reduce the number of suspects, making their work faster and more precise. Eye color is a polygenic phenotype, and many genetic variants have been highlighted, with the major contributor being the HERC2-OCA2 locus, where many single nucleotide variations (SNPs) were identified. Interestingly, the HERC2-OCA2 locus, containing the intronic SNP rs12913832, the major eye color determinant, shows a high level of evolutionary conservation across many species of vertebrates. Currently, there are some genetic panels to predict eye color by genomic DNA analysis, even if the exact role of the SNP variants in the formation of eye color is still poorly understood, with a low level of predictivity in the so-called intermediate eye color. Many variants in OCA2, HERC2, and other genes lie in introns or correspond to synonymous variants, highlighting greater complexity in the mechanism of action of such genes than a simple missense variation. Here, we show the main genes involved in oculocutaneous pigmentation and their structural and functional features, as well as which genetic variants show the highest level of eye color predictivity in currently used FDP assays. Despite the great recent advances and impact of FDP in criminal cases, it is necessary to enhance scientific research to better understand the mechanism of action behind each genetic variant involved in eye color, with the goal of obtaining higher levels of prediction.

Regulation of UV-B-Induced Inflammatory Mediators by Activity-Dependent Neuroprotective Protein (ADNP)-Derived Peptide (NAP) in Corneal Epithelium

The corneal epithelium, representing the outermost layer of the cornea, acts as a barrier to protect the eye against external insults such as ultraviolet B (UV-B) radiations. The inflammatory response induced by these adverse events can alter the corneal structure, leading to visual impairment. In a previous study, we demonstrated the positive effects of NAP, the active fragment of activity-dependent protein (ADNP), against oxidative stress induced by UV-B radiations. Here, we investigated its role to counteract the inflammatory event triggered by this insult contributing to the disruption of the corneal epithelial barrier. The results indicated that NAP treatment prevents UV-B-induced inflammatory processes by affecting IL-1β cytokine expression and NF-κB activation, as well as maintaining corneal epithelial barrier integrity. These findings may be useful for the future development of an NAP-based therapy for corneal disease.

Modulatory activity of ADNP on the hypoxia‑induced angiogenic process in glioblastoma

Glioblastoma multiforme (GBM) is a brain cancer with a poor prognosis that affects adults. This is a solid tumor characterized by a high rate of cell migration and invasion. The uncontrolled cell proliferation creates hypoxic niches in the tumor mass, which leads to the overexpression of hypoxia‑inducible factors (HIFs). This induces the activation of the vascular endothelial growth factor (VEGF), which is responsible for uncontrolled neoangiogenesis. Recent studies have demonstrated the anti‑invasive effect of pituitary adenylate cyclase‑activating peptide (PACAP) in GBM. PACAP effects on the central nervous system are also mediated through the activity‑dependent neuroprotective protein (ADNP) activation. To date, no evidence exists regarding its role in GBM. Therefore, the ADNP involvement in GBM was investigated. By analyzing ADNP expression in a human GBM sample through confocal microscopy, a high ADNP immunoreactivity was detected in most glial cells and its predominant expression in hypoxic areas overexpressing HIF‑1α was highlighted. To investigate the role of ADNP on the HIF‑VEGF axis in GBM, a human U87MG GBM cell line was cultured with a hypoxic mimetic agent, deferoxamine, and cells were treated with the smallest active fragment of ADNP, known as NAP. The protein expression and distribution of HIF‑1α and VEGF was detected using western blot analysis and immunofluorescence assay. Results demonstrated that ADNP modulates the hypoxic‑angiogenic pathway in GBM cells by reducing VEGF secretion, detected through ELISA assay, as well as modulating their migration, assessed through wound healing assay. Although deeper investigation is necessary, the present study suggested that ADNP could be involved in PACAP anti‑invasive effects in GBM.

PHF21A Related Disorder: Description of a New Case

PHF21A (PHD finger protein 21A) gene, located in the short arm of chromosome 11, encodes for BHC80, a component of the Lysine Specific Demethylase 1, Corepressor of REST (LSD1-CoREST) complex. BHC80 is mainly expressed in the human fetal brain and skeletal muscle and acts as a modulator of several neuronal genes during embryogenesis. Data from literature relates PHF21A variants with Potocki-Shaffer Syndrome (PSS), a contiguous gene deletion disorder caused by the haploinsufficiency of PHF21A, ALX4, and EXT2 genes. Clinical cardinal features of PSS syndrome are multiple exostoses (due to the EXT2 involvement), biparietal foramina (due to the ALX4 involvement), intellectual disability, and craniofacial anomalies (due to the PHF21A involvement). To date, to the best of our knowledge, a detailed description of PHF21A-related disorder clinical phenotype is not described in the literature; in fact, only 14 subjects with microdeletion frameshift or nonsense variants concerning only PHF21A gene have been reported. All reported cases did not present ALX4 or EXT2 variants, and their clinical features did not fit with PSS diagnosis. Herein, by using Exome sequencing, and Sanger sequencing of the region of interest, we describe a case of a child with a paternally inherited (mosaicism of 5%) truncating variant of the PHF21A gene (c.649_650del; p.Gln217ValfsTer6), and discuss the new evidence. In conclusion, these patients showed varied clinical expressions, mainly including the presence of intellectual disability, epilepsy, hypotonia, and dysmorphic features. Our study contributes to describing the genotype-phenotype spectrum of patients with PHF21A-related disorder; however, the limited data in the literature have been unable to provide a precise diagnostic protocol for patients with PHF21A-related disorder.

Identification of a Novel Missense Mutation of POLR3A Gene in a Cohort of Sicilian Patients with Leukodystrophy

Recessive mutations in the POLR3A gene cause POLR3-HLD (the second-most-common form of childhood-onset hypomyelinating leukodystrophy), a neurodegenerative disorder featuring deficient cerebral myelin formation. To date, more than 140 POLR3A (NM_007055.3) missense mutations are related to the pathogenesis of POLR3-related leukodystrophy and spastic ataxia. Herein, in a cohort of five families from Sicily (Italy), we detected two cases of patients affected by POLR3-related leukodystrophy, one due to a compound heterozygous mutation in the POLR3A gene, including a previously undescribed missense mutation (c.328A > G (p.Lys110Glu)). Our study used an in-house NGS gene panel comprising 41 known leukodystrophy genes. Successively, we used a predictive test supporting the missense mutation as causative of disease, thus this mutation can be considered “Likely Pathogenic” and could be as a new pathogenetic mutation of the POLR3A gene causing a severe form of POLR3-HLD.

Allelic Variations in the Human Genes TMPRSS2 and CCR5, and the Resistance to Viral Infection by SARS-CoV-2

During the first wave of COVID-19 infection in Italy, the number of cases and the mortality rates were among the highest compared to the rest of Europe and the world. Several studies demonstrated a severe clinical course of COVID-19 associated with old age, comorbidities, and male gender. However, there are cases of virus infection resistance in subjects living in close contact with infected subjects. Thus, to explain the predisposition to virus infection and to COVID-19 disease progression, we must consider, in addition to the genetic variability of the virus and other environmental or comorbidity conditions, the allelic variants of specific human genes, directly or indirectly related to the life cycle of the virus. Here, we analyzed three human genetic polymorphisms belonging to the TMPRSS2 and CCR5 genes in a sample population from Sicily (Italy) to investigate possible correlations with the resistance to viral infection and/or to COVID-19 disease progression as recently described in other human populations. Our results did not show any correlations of the rs35074065, rs12329760, and rs333 polymorphisms with SARS-CoV-2 infection or with COVID-19 disease severity. Further studies on other human genetic polymorphisms should be performed to identify the major human determinants of SARS-CoV-2 viral resistance.

Modulatory role of PACAP and VIP on HIFs expression in lung adenocarcinoma

Lung adenocarcinoma is the most frequent form of non-small cell lung cancer. Inside the tumor mass, uncontrolled cell proliferation generates hypoxic areas leading to activation of hypoxia-inducible factors (HIFs) responsible for neovascularization and tumor metastasis. Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are two neuropeptides widely distributed in respiratory organs. Previous studies have demonstrated that these peptides interfere with hypoxic pathways in various diseases, including tumors. However, their modulatory role in HIFs expression in lung adenocarcinomas has not yet been evaluated. In the present paper, we detected the expression profile of PACAP, VIP and related receptors in healthy and adenocarcinoma human lung tissue. To characterize peptides' modulatory effects on HIFs expression, we also exposed A549 lung adenocarcinoma cells and human normal bronchial epithelial BEAS-2B cells to microenvironmental hypoxia by treating them with deferoxamine (DFX). The results showed that PACAP and VIP significantly reduced HIF-1α and HIF-2α levels in both cell lines following hypoxic stress. The HIF-3α expression profile was related to cellular phenotype as it was lower in BEAS-2B and higher in A549 cells under low oxygen tension. In lung adenocarcinoma cells, peptide treatment restored HIF-3 α expression to control levels. These results suggest that endogenous PACAP and VIP exert controversial roles in cellular hypoxic microenvironments depending on the pathophysiological conditions of the lung tissue.

Targeting the miRNA-155/TNFSF10 network restrains inflammatory response in the retina in a mouse model of Alzheimer's disease

Age-related disorders, such as Alzheimer’s disease (AD) and age-related macular degeneration (AMD) share common features such as amyloid-β (Aβ) protein accumulation. Retinal deposition of Aβ aggregates in AMD patients has suggested a potential link between AMD and AD. In the present study, we analyzed the expression pattern of a focused set of miRNAs, previously found to be involved in both AD and AMD, in the retina of a triple transgenic mouse model of AD (3xTg-AD) at different time-points. Several miRNAs were differentially expressed in the retina of 3xTg-AD mice, compared to the retina of age-matched wild-type (WT) mice. In particular, bioinformatic analysis revealed that miR-155 had a central role in miRNA-gene network stability, regulating several pathways, including apoptotic and inflammatory signaling pathways modulated by TNF-related apoptosis-inducing ligand (TNFSF10). We showed that chronic treatment of 3xTg-AD mice with an anti-TNFSF10 monoclonal antibody was able to inhibit the retinal expression of miR-155, which inversely correlated with the expression of its molecular target SOCS-1. Moreover, the fine-tuned mechanism related to TNFSF10 immunoneutralization was tightly linked to modulation of TNFSF10 itself and its death receptor TNFRSF10B, along with cytokine production by microglia, reactive gliosis, and specific AD-related neuropathological hallmarks (i.e., Aβ deposition and Tau phosphorylation) in the retina of 3xTg-AD mice. In conclusion, immunoneutralization of TNFSF10 significantly preserved the retinal tissue in 3xTg-AD mice, suggesting its potential therapeutic application in retinal degenerative disorders.

Effect of PACAP on Hypoxia-Induced Angiogenesis and Epithelial-Mesenchymal Transition in Glioblastoma

Pituitary adenylate cyclase-activating polypeptide (PACAP) exerts different effects in various human cancer. In glioblastoma (GBM), PACAP has been shown to interfere with the hypoxic micro-environment through the modulation of hypoxia-inducible factors via PI3K/AKT and MAPK/ERK pathways inhibition. Considering that hypoxic tumor micro-environment is strictly linked to angiogenesis and Epithelial–Mesenchymal transition (EMT), in the present study, we have investigated the ability of PACAP to regulate these events. Results have demonstrated that PACAP and its related receptor, PAC1R, are expressed in hypoxic area of human GBM colocalizing either in epithelial or mesenchymal cells. By using an in vitro model of GBM cells, we have observed that PACAP interferes with hypoxic/angiogenic pathway by reducing vascular-endothelial growth factor (VEGF) release and inhibiting formation of vessel-like structures in H5V endothelial cells cultured with GBM-conditioned medium. Moreover, PACAP treatment decreased the expression of mesenchymal markers such as vimentin, matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9) as well as CD44 in GBM cells by affecting their invasiveness. In conclusion, our study provides new insights regarding the multimodal role of PACAP in GBM malignancy.

Morphological Evidence of Telocytes in Skeletal Muscle Interstitium of Exercised and Sedentary Rodents

Skeletal muscle atrophy, resulting from states of hypokinesis or immobilization, leads to morphological, metabolic, and functional changes within the muscle tissue, a large variety of which are supported by the stromal cells populating the interstitium. Telocytes represent a recently discovered population of stromal cells, which has been increasingly identified in several human organs and appears to participate in sustaining cross-talk, promoting regenerative mechanisms and supporting differentiation of local stem cell niche. The aim of this morphologic study was to investigate the presence of Telocytes in the tibialis anterior muscle of healthy rats undergoing an endurance training protocol for either 4 weeks or 16 weeks compared to sedentary rats. Histomorphometric analysis of muscle fibers diameter revealed muscle atrophy in sedentary rats. Telocytes were identified by double-positive immunofluorescence staining for CD34/CD117 and CD34/vimentin. The results showed that Telocytes were significantly reduced in sedentary rats at 16 weeks, while rats subjected to regular exercise maintained a stable Telocytes population after 16 weeks. Understanding of the relationship between Telocytes and exercise offers new chances in the field of regenerative medicine, suggesting possible triggers for Telocytes in sarcopenia and other musculoskeletal disorders, promoting adapted physical activity and rehabilitation programmes in clinical practice.

Beyond virology: environmental constraints of the first wave of COVID-19 cases in Italy

Global warming and air pollution affect the transmission pathway and the survival of viruses, altering the human immune system as well. The first wave of the COVID-19 pandemic dramatically highlights the key roles of climate and air chemistry in viral epidemics. The elongated form of the Italian peninsula and the two major islands (the largest in Europe) is a perfect case study to assess some of these key roles, as the fate of the virus is mirroring the industrialization in the continental part of our country. Fine particulate matter (PM2.5), geography, and climate explain what is happening in Italy and support cleaner air actions to address efficiently other outbreaks. Besides the environmental factors, future works should also address the genetic difference among individuals to explain the spatial variability of the human response to viral infections.

The Interplay between Fe3O4 Superparamagnetic Nanoparticles, Sodium Butyrate, and Folic Acid for Intracellular Transport

Combined treatments which use nanoparticles and drugs could be a synergistic strategy for the treatment of a variety of cancers to overcome drug resistance, low efficacy, and high-dose-induced systemic toxicity. In this study, the effects on human colon adenocarcinoma cells of surface modified Fe₃O₄ magnetic nanoparticles (MNPs) in combination with sodium butyrate (NaBu), added as a free formulation, were examined demonstrating that the co-delivery produced a cytotoxic effect on malignant cells. Two different MNP coatings were investigated: a simple polyethylene glycol (PEG) layer and a mixed folic acid (FA) and PEG layer. Our results demonstrated that MNPs with FA (FA-PEG@MNPs) have a better cellular uptake than the ones without FA (PEG@MNPs), probably due to the presence of folate that acts as an activator of folate receptors (FRs) expression. However, in the presence of NaBu, the difference between the two types of MNPs was reduced. These similar behaviors for both MNPs likely occurred because of the differentiation induced by butyrate that increases the uptake of ferromagnetic nanoparticles. Moreover, we observed a strong decrease of cell viability in a NaBu dose-dependent manner. Taking into account these results, the cooperation of multifunctional MNPs with NaBu, taking into consideration the particular cancer-cell properties, can be a valuable tool for future cancer treatment.

PACAP Modulates the Autophagy Process in an In Vitro Model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of complex etiology leading to motor neuron degeneration. Many gene alterations cause this pathology, including mutation in Cu, Zn superoxide dismutase (SOD1), which leads to its gain of function. Mutant SOD1 proteins are prone to aberrant misfolding and create aggregates that impair autophagy. The hypoxic stress is strictly linked to the disease progression since it induces uncontrolled autophagy activation and the consequent high rates of cell death. Previously, we showed that pituitary adenylate cyclase-activating polypeptide (PACAP) exerts neurotrophic activity in cultured mSOD1 motor neurons exposed to serum deprivation. To date, no studies have examined whether the protective effect of PACAP on mSOD1 cells exposed to hypoxic insult is mediated through the regulation of the autophagy process. In the present study, we used the neuroblastoma-spinal cord-34 (NSC-34) cell line, stably expressing human wild type or mutant SOD1 G93A, to represent a well characterized in vitro model of a familial form of ALS. These cells were exposed to 100-µM desferrioxamine mesylate salt for 24h, to mimic the hypoxic stress affecting motor neurons during the disease progression. Our results showed that PACAP treatment significantly reduced cell death and hypoxia-induced mSOD1 accumulation by modulating the autophagy process in G93A motor neurons, as revealed by the decreased LC3II and the increased p62 levels, two autophagy indicators. These results were also confirmed by evaluating the vacuole formation detected through light chain 3 (LC3) immunofluorescence. Furthermore, the PACAP effects on autophagy seem to be mediated through the activation of the MAPK/ERK signaling pathway. Overall, our data demonstrated that PACAP exerts an ameliorative effect on the mSOD1 motor neuron viability by modulating a hypoxia-induced autophagy process through activation of MAPK/ERK signaling cascade.

Effect of a Bone Marrow-Derived Extracellular Matrix on Cell Adhesion and Neural Induction of Dental Pulp Stem Cells

Extracellular matrix (ECM) represents an essential component of the cellular niche. In this conditioned microenvironment, the proliferation rates and differentiation states of stem cells are regulated by several factors. In contrast, in in vitro experimental models, cell growth, or induction procedures toward specific cell lines usually occur in contact with plastic, glass, or biogel supports. In this study, we evaluated the effect of a decellularized ECM, derived from bone marrow stem cells, on the neuronal differentiation of mesenchymal stem cells (MSCs) extracted from dental pulp (Dental Pulp Stem Cells - DPSCs). Since DPSCs derive from neuroectodermal embryonic precursors, they are thought to have a greater propensity toward neuronal differentiation than MSCs isolated from other sources. We hypothesized that the presence of a decellularized ECM scaffold could act positively on neuronal-DPSC differentiation through reproduction of an in vivo-like microenvironment. Results from scanning electron microscopy, immunofluorescence, and gene expression assays showed that ECM is able to positively influence the morphology of cells and their distribution and the expression of specific neuronal markers (i.e., NF-L, NF-M, NF-H, PAX6, MAP2).

Protective effect of PACAP against ultraviolet B radiation-induced human corneal endothelial cell injury

The human cornea, a sophisticated example of natural engineering, is composed in the innermost layer by endothelial cells maintaining stromal hydration and clarity. Different types of insults, including ultraviolet (UV) radiations, can lead to corneal opacity due to their degenerative and limited proliferative capability. In our previous studies, we have shown the protective effects of pituitary adenylate cyclase activating polypeptide (PACAP) in human corneal endothelial cells (HCECs), after growth factors deprivation. The aim of the present work has been to investigate the effect of this peptide on UV-B-induced HCECs injury. The results have shown that UV-B irradiations induced apoptotic cells death and consequently alteration in human corneal endothelial barrier. We found that PACAP treatment significantly increased viability, trans-endothelial electrical resistance and tight junctions expression of HCECs exposed to UV-B insult. In conclusion, data have suggested that this peptide could have protective effect to preserve the physiological state of human corneal endothelium exposed to UV-B damage.

Swordfish or Shark Slice? A Rapid Response by COIBar-RFLP

Market transparency is in strong demand by consumers, and the authentication of species is an important step for seafood traceability. In this study, a simple molecular strategy, COIBar–RFLP (cytochrome oxidase I barcode–restriction fragment length polymorphism), is proposed to unveil commercial fraud based on the practice of species substitution in the swordfish trade. In particular, COI barcoding allowed the identification of the species Prionace glauca, Mustelus mustelus, and Oxynotus centrina in slices labeled as Xiphias gladius. Furthermore, the enzymatic digestion of COI amplicons using the MboI restriction endonuclease allowed the simultaneous discrimination of the four species. Interestingly, an intraspecific differential MboI pattern was obtained for the swordfish samples. This pattern was useful to differentiate the two different clades revealed in this species by phylogenetic analyses using several molecular markers. These results indicate the need to strengthen regulations and define molecular tools for combating the occurrence of fraud along the seafood supply chain and show that COIBar–RFLP could become a standardized molecular tool to assess seafood authenticity.

Beneficial effects of curtailing immune susceptibility in an Alzheimer's disease model

BACKGROUND

Currently, there are no effective therapeutic options for Alzheimer's disease, the most common, multifactorial form of dementia, characterized by anomalous amyloid accumulation in the brain. Growing evidence points to neuroinflammation as a major promoter of AD. We have previously shown that the proinflammatory cytokine TNFSF10 fuels AD neuroinflammation, and that its immunoneutralization results in improved cognition in the 3xTg-AD mouse.

METHODS

Here, we hypothesize that inflammatory hallmarks of AD might parallel with central and peripheral immune response dysfunction. To verify such hypothesis, we used a triple transgenic mouse model of AD. 3xTg-AD mice were treated for 12 months with an anti-TNFSF10 antibody, and thereafter immune/inflammatory markers including COX2, iNOS, IL-1β and TNF-α, CD3, GITR, and FoxP3 (markers of regulatory T cells) were measured in the spleen as well as in the hippocampus.

RESULTS

Spleens displayed accumulation of amyloid-β1-42 (Aβ1-42), as well as high expression of Treg cell markers FoxP3 and GITR, in parallel with the increased levels of inflammatory markers COX2, iNOS, IL-1β and TNF-α, and blunted IL-10 expression. Moreover, CD3 expression was increased in the hippocampus, consistently with FoxP3 and GITR. After chronic treatment of 3xTg-AD mice with an anti-TNFSF10 antibody, splenic FoxP3, GITR, and the above-mentioned inflammatory markers expression was restored to basal levels, while expression of IL-10 was increased. A similar picture was observed in the hippocampus. Such improvement of peripheral and CNS inflammatory/immune response was associated with decreased microglial activity in terms of TNFα production, as well as decreased expression of both amyloid and phosphorylated tau protein in the hippocampus of treated 3xTg-AD mice. Interestingly, we also reported an increased expression of both CD3 and FoxP3, in sections from human AD brain.

CONCLUSIONS

We suggest that neuroinflammation in the brain of 3xTg-AD mice triggered by TNFSF10 might result in a more general overshooting of the immune response. Treatment with an anti-TNFSF10 antibody blunted inflammatory processes both in the spleen and hippocampus. These data confirm the detrimental role of TNFSF10 in neurodegeneration, and corroborate the hypothesis of the anti-TNFSF10 strategy as a potential treatment to improve outcomes in AD.

Caffeine Effect on HIFs/VEGF Pathway in Human Glioblastoma Cells Exposed to Hypoxia

BACKGROUND

Caffeine represents the most used psychoactive drug in the world acting through different mechanisms of action and on several molecular targets. It exerts an anti-cancer role in glioblastoma multiforme (GBM). This neoplasia is characterized by extensive hypoxic foci triggering hypoxia-inducible factors (HIFs) expression. Among these factors, HIF-1α performs a crucial role in the induction of vascular endothelium growth factor (VEGF), a key player in angiogenesis and cell migration.

METHODS

In this work, we have investigated whether caffeine counteracts GBM progression by modulating hypoxic event. Moreover, we analyzed the activation of phosphoinositide three kinase (PI3K)/Akt and mammalian mitogen activated protein kinase/Erk kinase (MAPK/ERK) signaling cascades.

RESULTS

Our results have indicated that this psychostimulant drug significantly reduced HIF-1α and VEGF expression in GBM cells exposed to hypoxia. This effect is mediated through inhibition of PI3K/Akt and MAPK/ERK signaling pathways both implied in HIFs regulation.

CONCLUSION

The present data give new insight into antitumor activity of caffeine during GBM progression.

Involvement of A3 Adenosine Receptor in Neuroblastoma Progression via Modulation of the Hypoxic/Angiogenic Pathway

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. The clinical course may range from spontaneous regression towards ganglioneuroblastoma/ganglioneuroma or maturation to a very aggressive form characterized by an extensive hypoxic area. In solid tumors, extracellular microenvironment hypoxia induces the transcription of hypoxia-inducible factors (HIFs) leading to synthesis of pro-angiogenic factor, VEGF; also, it increases extracellular adenosine production from ATP breakdown. To date, the role of this nucleoside in the hypoxic/angiogenic pathway characterizing the core of cancer mass has not been investigated yet. Therefore, the aim of the present study was to analyze the adenosine effect on modulation of the HIF-1α/2α/VEGF pathway mediated through A₃ AR binding. To this end, we have used a selective A₃ AR agonist IB-MECA or antagonist VUF 5574 in an in vitro model of malignant undifferentiated and all-trans retinoic acid (RA)-differentiated SH-SY5Y cells, representing the benign form of NB. Our results have shown that specific A₃ AR stimulation induces HIF and VEGF expression through the activation of mitogen-activated protein kinase/Erk kinase signaling cascade. In conclusion, the data suggest that A₃ AR may represent a marker of NB malignancy as well as a drug target for treatment of this solid tumor. Graphical Abstract.

Deletions of Chromosome 7q Affect Nuclear Organization and HLXB9Gene Expression in Hematological Disorders

The radial spatial positioning of individual gene loci within interphase nuclei has been associated with up- and downregulation of their expression. In cancer, the genome organization may become disturbed due to chromosomal abnormalities, such as translocations or deletions, resulting in the repositioning of genes and alteration of gene expression with oncogenic consequences. In this study, we analyzed the nuclear repositioning of HLXB9 (also called MNX1), mapping at 7q36.3, in patients with hematological disorders carrying interstitial deletions of 7q of various extents, with a distal breakpoint in 7q36. We observed that HLXB9 remains at the nuclear periphery, or is repositioned towards the nuclear interior, depending upon the compositional properties of the chromosomal regions involved in the rearrangement. For instance, a proximal breakpoint leading the guanine-cytosine (GC)-poor band 7q21 near 7q36 would bring HLXB9 to the nuclear periphery, whereas breakpoints that join the GC-rich band 7q22 to 7q36 would bring HLXB9 to the nuclear interior. This nuclear repositioning is associated with transcriptional changes, with HLXB9 in the nuclear interior becoming upregulated. Here we report an in cis rearrangement, involving one single chromosome altering gene behavior. Furthermore, we propose a mechanistic model for chromatin reorganization that affects gene expression via the influences of new chromatin neighborhoods.

NAP modulates hyperglycemic-inflammatory event of diabetic retina by counteracting outer blood retinal barrier damage

Diabetic retinopathy (DR) is a common microvascular complication of diabetes. Prolonged hyperglycemia stimulates inflammatory pathway characterized by the release of some cytokines leading to the impairment of blood retinal barrier (BRB). NAP exerts a protective effect in various eye diseases, including DR. So far, the role of NAP in the modulation of inflammatory event during early phase of this pathology has not been investigated yet. In the current study, we have studied the retinal protective effect of NAP, injected into the eye, in diabetic rats. NAP treatment exerts a dual effect downregulating interleukin (IL)-1β and its related receptors and upregulating IL-1Ra expression. We have also tested the role of this peptide in human retinal epithelial cells (ARPE19) cultured on a semipermeable support and exposed to hyperglycemic-inflammatory insult, representing a in vitro model of diabetic macular edema, a clinical manifestation of DR. The results have shown that NAP prevents outer BRB impairment by upregulating the tight junctions. In conclusion, deepened characterization of NAP action mechanism on hyperglycemic-inflammatory damage may be useful to develop a new strategy to prevent retinal damage during DR.

Buccal micronucleus assay in human populations from Sicily (Italy) exposed to petrochemical industry pollutants

Petroleum refinery workers are potentially exposed to a wide range of petrochemical industry pollutants (PIP), such as benzene and 1,3-butadiene, cancer-related compounds classified as carcinogenic to humans. The aim of this study was to evaluate the cytogenetic effects of exposure to PIP from two industrialised areas in South/East Sicily (Italy) using a micronucleus (MN) assay and other nuclear anomalies (ONA) on exfoliated buccal cells. Results highlighted not only a statistically significant high level of increase of MN in petroleum refinery (PR) workers, but also in the subjects not working in PR but living in the industrialised area. The ONA analysis showed a highly significant increase in karyolytic cells in exposed vs unexposed subjects, in contrast to a decrease in differentiated cells. These results suggest the presence of a cytotoxic effect in the oral mucosa cells, probably related to the pollutant compounds present in the environment close to the petrochemical industries. Our data confirm that the analysis of exfoliated buccal cells is a useful and simple non-invasive method to evaluate the genotoxic/cytotoxic effects of pollutants in a specific area. To avoid confounding factors due to the different lifestyles of the human subjects, the above assays could be better applied on farm animals, which have a relatively consistent lifestyle and, in some cases, a very low genetic heterogeneity.

PACAP through EGFR transactivation preserves human corneal endothelial integrity

The corneal endothelium is composed of a single hexagonal-shaped cells layer adherent to the Descemet's membrane. The primary function of these cells is maintaining of tissue clarity by regulating its hydration. Trauma, aging or other pathologies cause their loss, counterbalanced by enlargement of survived cells unable to guarantee an efficient fluid pumping to and from the stroma. Regenerative medicine using human corneal endothelial cells (HCECs) isolated from peripheral corneal-scleral tissue of a donor could be an attractive solution, overcoming transplantation problems. In a previous study, we have demonstrated that HCECs treatment with pituitary adenylate cyclase-activating polypeptide (PACAP) following growth factors deprivation prevents their degeneration. However, the molecular mechanism mediating this effect has not been clarified, yet. Here, we have shown for the first time the expression of PACAP and its receptor (PAC1R) in human corneal endothelium and demonstrated that this peptide, selectively binding to PAC1R, induces epidermal growth factor receptor (EGFR) phosphorylation and the MAPK/ERK1/2 signaling pathway activation. In conclusion, our data have suggested that PACAP could represent an important trophic factor in maintaining human corneal endothelial integrity through EGFR transactivation. Therefore, PACAP, as well as epidermal growth factor and fibroblast growth factor, could co-operate to guarantee tissue physiological functioning by supporting corneal endothelial barrier integrity.

Molecular mechanisms involved in the protective effect of pituitary adenylate cyclase-activating polypeptide in an in vitro model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the loss of upper and lower motor neurons. Based on transcriptional profiles of motor cortex samples, in a previous work, we were able to classify two subgroups of sporadic ALS (SALS) patients, named SALS1 and SALS2. A further meta-analysis study has revealed sixteen drug targets commonly deregulated in SALS2 and superoxide dismutase 1 (SOD1) G93A mice. The identified candidate drug targets included pituitary adenylate cyclase-activating polypeptide (PACAP), epidermal growth factor receptor (EGFR) and matrix metallopeptidase-2 (MMP-2). By using a motor neuron-like hybrid cell line (NSC-34) expressing human SOD1 G93A as an in vitro model of ALS, here we investigated the functional correlation among these three genes. Our results have shown that PACAP increases cell viability following serum deprivation. This effect is induced through EGFR transactivation mediated by protein kinase A stimulation. Furthermore, EGFR phosphorylation activates mitogen-activated protein kinases/extracellular signal-regulated kinases 1 and 2 survival signaling pathway and increases MMP-2 expression, significantly reduced by serum starvation. These results suggest that a deeper characterization of mechanisms involved in PACAP/EGFR/MMP-2 axis activation in G93A SOD1 mutated neurons may allow identifying new targets for ALS therapy.

PACAP and VIP regulate hypoxia-inducible factors in neuroblastoma cells exposed to hypoxia

Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are two related peptides acting as neurotransmitters/neuromodulators in central and peripheral nervous system. They are also involved in cancer showing a controversial role. Particulary, they are implicated in neuroblastoma differentiation (NB). This pediatric tumor can evolve to a malignant metastatic disease or spontaneously regress towards a benign form, known as ganglioneuroblastoma/ganglioneuroma. A negative hallmark of neoplasia progression is represented by hypoxic microenvironment. Low oxygen tension induces activation of hypoxia-inducible factors (HIFs) promoting cells proliferation and metastasis formation. Moreover, HIFs trigger vascular endothelial growth factor (VEGF) release favouring high-risk NB phenotype development. In the present work, we have investigated for the first time, if PACAP and VIP interfere with NB differentiation through modulation of hypoxic/angiogenic process. To this end, we analyzed their effect in malignant undifferentiated and all-trans retinoic acid (RA) differentiated SH-SY5Y cells, representing the benign form of this tumor. Our results have suggested tha both peptides, but predominantly VIP, induce NB differentiation into benign form by regulating HIFs, VEGF and VEGFRs expression and distribution. All these data give new insight regarding PACAP/VIP regulatory role in NB progression.

The Proinflammatory Cytokine GITRL Contributes to TRAIL-mediated Neurotoxicity in the HCN-2 Human Neuronal Cell Line

BACKGROUND

Cytokines belonging to the TNF superfamily play a relevant role in neurodegenerative processes. Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL), released during neuronal injury, has proven to potently mediate and sustain neurotoxic processes leading to neuronal death. Similarly to TRAIL, the cytokine Glucocorticoid-induced TNF receptor ligand (GITRL) is able to transduce proapoptotic signals. In spite of the array of reports suggesting relationships between TRAIL and other cytokines, scanty data are, so far, available about a GITRL/TRAIL crosstalk.

METHODS

Here, we investigated possible interactions between TRAIL and the GITRL system in an in vitro model of neurodegeneration, using the human cortical neuronal cell line HCN-2. Cultured HCN-2 neurons were incubated at different times with GITRL and/or TRAIL, and thereafter nucleic acid and protein expression were measured. Real-time PCR analysis showed that the human cortical neuronal cell line HCN-2 does not express GITRL mRNA, but the latter is induced after treatment with TRAIL. In addition, HCN-2 cells did not express the GITRL receptor GITR mRNA, neither in control cultures, nor after treatment with TRAIL. All mRNA data were confirmed by western blot analysis of proteins. Cell viability assay showed that TRAIL, when associated to GITRL, was able to exert additive toxic effects. A counterproof was provided in experiments performed blocking GITRL, in which TRAIL-mediated toxicity appeared significantly reduced. Results suggest that GITRL/TRAIL redundancy during neurodegenerative processes implies extended potentiation of detrimental effects of both cytokines on neurons, eventually leading to larger cell damage and death.

CONCLUSION

Finally, characterization of novel molecular targets within the TRAIL/GITRL interplay may represent a platform for innovative therapy of neurodegenerative disorders.

Phosphorylated nucleolar Tau protein is related to the neuronal in vitro differentiation

Tau is a multifunctional protein, originally identified as a cytoplasmic protein associated with microtubules. It is codified by the MAPT gene, and the alternative splicing, in the neuronal cells, results in six different isoforms. Tau was subsequently observed in the cell nucleus, where its function is not yet clearly understood. Here, we studied the MAPT gene and the cellular localization of the AT8 and Tau-1 epitopes of Tau protein, in the SK-N-BE cell line, which differentiates in neuronal-like cells after retinoic acid treatment. These epitopes correspond to the phosphorylated Ser202/Thr205 and unphosphorylated Pro189/Gly207 amino acid residues, respectively, possibly involved in conformational changes of the protein. Our results demonstrated the presence of the smaller Tau isoform (352 amino acids), whose amount increases in differentiated SK-N-BE cells, with Tau-1/AT8 nuclear distribution related to the differentiation process. Tau-1 showed a spot-like nucleolar localization, in both replicative and differentiated cells, while AT8 was only detected in the differentiated cells, diffusely occupying the entire nucleolar region. Moreover, in the replicative cells exposed to actinomycin-D, AT8 and Tau-1 move to the nucleolar periphery and colocalize, in few spots, with the upstream binding transcription factor (UBTF). Our results, also obtained with lymphocytes exposed to the mitogenic compound phytohaemagglutinin, indicate the AT8 epitope of Tau as a marker of neuronal cell differentiation, whose presence in the nucleolus appears to be related to rDNA transcriptional inactivation.

Rapid molecular identification of necrophagous diptera by means of variable-length intron sequences in the wingless gene

The arrival of arthropods at a corpse exhibits specific temporal patterns, and Diptera play a key role in the initial stages of the decomposition process. Thus, the correct species assignment of the insect larvae found on a decomposing body is an important step in forensic investigations. Here, we describe a molecular procedure to define the species at larval age found on a corpse more quickly and easily than current systems. Our method involves a unique PCR amplification of a DNA segment within the evolutionarily conserved wingless gene, involved in embryo development. The amplified DNA segment contains the fourth intron of wingless, which we found to be variable in length, from about 800 to 3000 bp, among species of necrophagous Diptera. The identification of the amplified segment size in species from Lucilia, Calliphora and Sarcophaga genera, allowed us to determine the species at larval age collected in the early stages of a decomposing body, with a simple PCR amplification and subsequent electrophoresis. This procedure may help in forensic investigations to estimate the minimum Post Mortem Interval (PMI-min) of a body colonized by these larvae, avoiding the use of time-consuming and/or more expensive procedures.

Heme oxygenase-1 nuclear translocation regulates bortezomibinduced cytotoxicity and mediates genomic instability in myeloma cells

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of clonal plasma cells in the bone marrow leading to bone destruction and bone marrow failure. Several molecular mechanisms underlie chemoresistance among which heme oxygenase-1 (HO-1) could play a major role. The aim of the present research was to evaluate the impact of HO-1 in MM following bortezomib (BTZ) treatment and how HO-1 is implicated in the mechanisms of chemoresistance. MM cells were treated for 24h with BTZ (15 nM), a boronic acid dipeptide inhibitor of the 26S proteasome used in the treatment of patients with MM as first-line therapy. We evaluated cell viability, reactive oxygen species (ROS) formation, endoplasmic reticulum (ER) stress, HO-1 expression and compartmentalization and cellular genetic instability. Results showed that BTZ significantly reduced cell viability in different MM cell lines and induced ER-stress and ROS formation. Concomitantly, we observed a significant overexpression of both HO-1 gene and protein levels. This effect was abolished by concomitant treatment with 4-phenybutirric acid, a molecular chaperone, which is known to reduce ER-stress. Surprisingly, inhibition of HO activity with SnMP (10μM) failed to increase BTZ sensitivity in MM cells whereas inhibition of HO-1 nuclear translocation by E64d, a cysteine protease inhibitor, increased sensitivity to BTZ and decreased genetic instability as measured by cytokinesis-block micronucleus assay. In conclusion, our data suggest that BTZ sensitivity depends on HO-1 nuclear compartmentalization and not on its enzymatic activity and this finding may represent an important tool to overcome BTZ chemoresistance in MM patients.

Modulation of IL-1β and VEGF expression in rat diabetic retinopathy after PACAP administration

Diabetic retinopathy (DR) is a microvascular complication of diabetes. Hyperglycemic/hypoxic microenvironment concurs to aberrant angiogenesis characterizing the pathology and activates many downstream target genes including inflammatory cytokines and vasoactive peptides, such as interleukin-1β (IL-1β) and vascular endothelial growth factor (VEGF). It has been largely demonstrated that pituitary adenylate cyclase-activating peptide (PACAP) plays a protective effect in DR. In the present study, we investigated the role of PACAP to protect retinal tissue through IL-1β and VEGF expression. Diabetes was induced in rats by streptozotocin (STZ) injection, and one week later a single intravitreal injection of 100μM PACAP was administrated. Analyses of IL-1β and VEGF levels were performed three weeks after diabetes induction. The results demonstrated that a single intraocular administration of PACAP significantly reduced the expression of IL-1β in diabetic animals. Moreover, it affects VEGF and its receptors (VEGFRs) levels and interferes with their retinal layers distribution as showed by confocal microscopy analysis. In particular, PACAP treatment downregulates VEGF and VEGFRs that are increasingly expressed in STZ-treated animals as compared to controls. These results indicate that PACAP plays an important role to attenuate the early phase of DR.

Aging dependent effect of nuclear tau

Tau protein is characterized by a complex pattern of phosphorylation and is localized in the cytoplasm and nucleus in both neuronal and non-neuronal cells. Human AT100 nuclear tau, endowed by phosphorylation in Thr212/Ser214, was recently shown to decline in cornus ammonis 1 (CA1) and dentate gyrus (DG) in Alzheimer's disease (AD), but a defined function for this nuclear tau remains unclear. Here we show that AT100 progressively increases in the nuclei of neuronal and non-neuronal cells during aging, and decreases in the more severe AD stages, as recently shown, and in cancer cells (colorectal adenocarcinoma and breast cancer). AT100, in addition to a co-localization with the DAPI-positive heterochromatin, was detected in the nucleolus of pyramidal cells from the CA1 region, shown to be at its highest level in the more senescent cells and in the first stage of AD (ADI), and disappearing in the more severe AD cases (ADIV). Taking into account the nuclear distribution of AT100 during cell aging and its relation to the chromatin changes observed in degenerated neurons, as well as in cancerous cells, which are both cellular pathologies associated with age, we can consider the Thr212/Ser214 phosphorylated nuclear tau as a molecular marker of cell aging.

Nuclear Repositioning of the Non-Translocated HLXB9 Allele in the Leukaemia Cell Line GDM-1 Harbouring a t(6;7)(q23;q36)

Transcriptionally active and inactive topologically associated domains (TADs) occupy different areas in the cell nucleus, and chromosomal rearrangements relocating TADs could determine ectopic expression of the repositioned genes. In this study, we investigated the HLXB9 gene in a myeloid leukaemia cell line, GDM-1, known to harbour a rearrangement involving chromosome 7 with a breakpoint distal to HLXB9, highly expressed in these cells. We used FISH to target the regions involved in the translocation and to distinguish the translocated chromosome from the non-translocated one in interphase nuclei. Two-dimensional analysis of the interphase FISH data indicated that the 2 HLXB9 alleles had a different localisation in the cell nuclei, with the translocated allele consistently positioned in the nuclear periphery and the normal one in the more internal portion of the nucleus, known as the transcriptionally active compartment. Our data may indicate that HLXB9 transcripts in the GDM-1 cell line do not arise from the allele located in rearranged chromosome 7, suggesting that regulation of gene expression in cancer cells harbouring chromosomal translocations might be more complex than previously thought, paving the path to further investigations on mechanisms of gene expression.

Differential expression of PARK2 splice isoforms in an in vitro model of dopaminergic-like neurons exposed to toxic insults mimicking Parkinson's disease

Mutations in PARK2 (or parkin) are responsible for 50% of cases of autosomal-recessive juvenile-onset Parkinson's disease (PD). To date, 21 alternative splice variants of the human gene have been cloned. Yet most studies have focused on the full-length protein, whereas the spectrum of the parkin isoforms expressed in PD has never been investigated. In this study, the role of parkin proteins in PD neurodegeneration was explored for the first time by analyzing their expression profile in an in vitro model of PD. To do so, undifferentiated and all-trans-retinoic-acid (RA)-differentiated SH-SY5Y cells (which thereby acquire a PD-like phenotype) were exposed to PD-mimicking neurotoxins: 1-methyl-4-phenylpyridinium (MPP⁺ ) and 6-hydroxydopamine (6-OHDA) are widely used in PD models, whereas carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and carbobenzoxy-Leu-Leu-leucinal (MG132) interfere, respectively, with mitochondrial mitophagy and proteasomal degradation. Following treatment with each neurotoxin H1, the first parkin isoform to be cloned, was down-regulated compared to the respective controls both in undifferentiated and RA-differentiated cells. In contrast, the expression pattern of the minor splice isoforms varied as a function of the compound used: it was largely unchanged in both cell cultures (eg, H21-H6, H12, XP isoform) or it showed virtually opposite alterations in undifferentiated and RA-differentiated cells (eg, H20 and H3 isoform). This complex picture suggests that up- or down-regulation may be a direct effect of toxin exposure, and that the different isoforms may exert different actions in neurodegeneration via modulation of different molecular pathways.

Nicotine promotes blood retinal barrier damage in a model of human diabetic macular edema

More than 1 billion world's population actively smokes tobacco containing the bioactive component nicotine (NT). The biological role of this molecule is mediated through the activation of nicotinic cholinergic receptors, widely distributed in various human tissues including retinal pigmented epithelium. The long-term assumption of NT contributes to several diseases development such as diabetic retinopathy. The major complication of this pathology is the diabetic macular edema (DME), characterized by macular area thinning and blood-retinal barrier (BRB) breakdown. Retinal hyperglycemic/hypoxic microenvironment represents one of the main factors favoring DME progression by eliciting the hypoxia-inducible factors (HIFs) expression. The latter induce new vessels formation by stimulating cellular secretion of vascular endothelial growth factor (VEGF). The etiology of DME is multifactorial, but little is known about the risk factors linked to cigarette smoking, in particular to nicotine's contribution. In the present study, we have investigated the NT role in a model, in vitro, of DME, by evaluating its effect on outer BRB permeability and HIFs/VEGF expression following exposure to hyperglycemic/hypoxic insult. Our results have demonstrated that this compound alters outer BRB integrity exposed to high glucose and low oxygen pressure microenvironment by upregulating HIF-1α/HIF-2α, VEGF expression and ERK1/2 phosphorylation. These data have suggested that NT may play a negative role in active smokers affected by DME.

Caffeine Prevents Blood Retinal Barrier Damage in a Model, In Vitro, of Diabetic Macular Edema

Diabetic macular edema (DME) is the major cause of vision loss in patients affected by diabetic retinopathy. Hyperglycemia and hypoxia represent the key elements in the progression of these pathologies, leading to breakdown of the blood-retinal barrier (BRB). Caffeine, a psychoactive substance largely consumed in the world, is a nonselective antagonist of adenosine receptors (AR) and it possesses a protective effect in various diseases, including eye pathologies. Here, we have investigated the effect of this substance on BRB integrity following exposure to hyperglycemic/hypoxic insult. Retinal pigmented epithelial cells, ARPE-19, have been grown on semi-permeable supports mimicking an experimental model, in vitro, of outer BRB. Caffeine treatment has reduced cell monolayer permeability after exposure to high glucose and desferoxamine as shown by TEER and FITC-dextran permeability assays. This effect is also mediated through the restoration of membrane's tight junction expression, ZO-1. Moreover, we have demonstrated that caffeine is able to prevent outer BRB damage by inhibiting apoptotic cell death induced by hyperglycemic/hypoxic insult since it downregulates the proapoptotic Bax and upregulates the anti-apoptotic Bcl-2 genes. Although further studies are needed to better comprise the beneficial effect of caffeine, we can speculate that it might be used as an innovative drug for DME treatment. J. Cell. Biochem. 118: 2371-2379, 2017. © 2017 Wiley Periodicals, Inc.

Nap Interferes with Hypoxia-Inducible Factors and VEGF Expression in Retina of Diabetic Rats

The retinal microvascular damage is a complication of diabetic retinopathy (DR). Hyperglycemia and hypoxia are responsible of aberrant vessel's proliferation. The cellular response to hypoxia is mediated through activation of hypoxia-inducible factors (HIFs). Among these, HIF-1α modulates expression of its target gene, VEGF, whose upregulation controls the angiogenic event during DR development. In a previous study, we have demonstrated that a small peptide, NAP, is able to protect retina from hyperglycemic insult. Here, we have demonstrated that its intraocular administration in a rat model of diabetic retinopathy has reduced expression of HIF-1α, HIF-2α, and VEGF by increasing HIF-3α levels. These data have been also confirmed by immunolocalization study by confocal microscopy. Although these evidences need to be further deepened to understand the molecular mechanism involved in the protective NAP action, the present data suggest that this small peptide may be effective to prevent the development of this ocular pathology.