Publications by authors named "Annagrazia Adornetto"

36 Publications

The promise of neuroprotection by dietary restriction in glaucoma.

Neural Regen Res 2022 Jan;17(1):45-47

Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy.

Glaucoma, a progressive age-related optic neuropathy characterized by the death of retinal ganglion cells, is the most common neurodegenerative cause of irreversible blindness worldwide. The therapeutic management of glaucoma, which is limited to lowering intraocular pressure, is still a challenge since visual loss progresses in a significant percentage of treated patients. Restricted dietary regimens have received considerable attention as adjuvant strategy for attenuating or delaying the progression of neurodegenerative diseases. Here we discuss the literature exploring the effects of modified eating patterns on retinal aging and resistance to stressor stimuli.
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http://dx.doi.org/10.4103/1673-5374.314308DOI Listing
January 2022

Development and Translation of NanoBEO, a Nanotechnology-Based Delivery System of Bergamot Essential Oil Deprived of Furocumarins, in the Control of Agitation in Severe Dementia.

Pharmaceutics 2021 Mar 12;13(3). Epub 2021 Mar 12.

Pharmacotechnology Documentation and Transfer Unit, Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy.

Dementia is one of the most common causes of disability worldwide characterized by memory loss, cognitive impairment, and behavioral and psychological symptoms (BPSD), including agitation. Treatment of the latter consists of the off-label use of harmful atypical antipsychotics, though a significant reduction is afforded by pain control. The use of an essential oil endowed with analgesic properties and devoid of toxicity would represent an important option for the management of agitation in dementia. Therefore, the aim of this study was to engineer a nanotechnology delivery system based on solid lipid nanoparticles loaded with bergamot essential oil (BEO) and devised in the pharmaceutical form of an odorless cream (NanoBEO) to confirm its analgesic efficacy for further development and application to control agitation in dementia. BEO has proven strong antinociceptive and anti-allodynic properties and, in its bergapten-free form, it is completely devoid of phototoxicity. NanoBEO has been studied in vivo confirming the previously reported analgesic activity of BEO to which is now added its anti-itching properties. Due to the nanotechnology delivery system, the stability of titrated BEO components is guaranteed. Finally, the latter invention, currently under patent consideration, is smell-devoid allowing efficacy and safety to be established in double-blind clinical trials; until now the latter studies have been impeded in aromatherapy by the strong odor of essential oils. A clinical trial NCT04321889 has been designed to provide information about the efficacy and safety of NanoBEO on agitation and pain in patients suffering from severe dementia.
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http://dx.doi.org/10.3390/pharmaceutics13030379DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7999378PMC
March 2021

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition).

Autophagy 2021 Jan 8;17(1):1-382. Epub 2021 Feb 8.

University of Crete, School of Medicine, Laboratory of Clinical Microbiology and Microbial Pathogenesis, Voutes, Heraklion, Crete, Greece; Foundation for Research and Technology, Institute of Molecular Biology and Biotechnology (IMBB), Heraklion, Crete, Greece.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
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http://dx.doi.org/10.1080/15548627.2020.1797280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996087PMC
January 2021

Natural Products: Evidence for Neuroprotection to Be Exploited in Glaucoma.

Nutrients 2020 Oct 16;12(10). Epub 2020 Oct 16.

Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy.

Glaucoma, a leading cause of irreversible blindness worldwide, is an optic neuropathy characterized by the progressive death of retinal ganglion cells (RGCs). Elevated intraocular pressure (IOP) is recognized as the main risk factor. Despite effective IOP-lowering therapies, the disease progresses in a significant number of patients. Therefore, alternative IOP-independent strategies aiming at halting or delaying RGC degeneration is the current therapeutic challenge for glaucoma management. Here, we review the literature on the neuroprotective activities, and the underlying mechanisms, of natural compounds and dietary supplements in experimental and clinical glaucoma.
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http://dx.doi.org/10.3390/nu12103158DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7602834PMC
October 2020

Effects of caloric restriction on retinal aging and neurodegeneration.

Prog Brain Res 2020 18;256(1):189-207. Epub 2020 Aug 18.

Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy. Electronic address:

Glaucoma is the most common neurodegenerative cause of irreversible blindness worldwide. Restricted caloric regimens are an attractive approach for delaying the progression of neurodegenerative diseases. Here we review the current literature on the effects of caloric restriction on retinal neurons, under physiological and pathological conditions. We focused on autophagy as one of the mechanisms modulated by restricted caloric regimens and involved in the death of retinal ganglion cells (RGCs) over the course of glaucoma.
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http://dx.doi.org/10.1016/bs.pbr.2020.07.005DOI Listing
August 2020

The Role of Autophagy in Glaucomatous Optic Neuropathy.

Front Cell Dev Biol 2020 4;8:121. Epub 2020 Mar 4.

Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Rende, Italy.

Autophagy is a conserved lysosomal-dependent pathway responsible for the degradation of cytoplasmic macromolecules. Based on the mechanism of cargo delivery to lysosomes, mammalian cells can undergo micro, macro, and chaperone-mediated autophagy. Other than physiological turnover of proteins and organelles, autophagy regulates cellular adaptation to different metabolic states and stressful conditions by allowing cellular survival or, when overactivated, participating to cell death. Due to their structure and function, neurons are highly dependent on autophagy efficiency and dysfunction of the pathway has been associated with neurodegenerative disorders. Glaucomatous optic neuropathies, a leading cause of blindness, are characterized by the progressive loss of a selective population of retinal neurons, i.e., the retinal ganglion cells (RGCs). Here we review the current literature on the role of autophagy in the pathogenic process that leads to the degeneration of RGC in various experimental models of glaucoma exploring the modulation of the pathway as a potential therapeutic intervention.
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http://dx.doi.org/10.3389/fcell.2020.00121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7066980PMC
March 2020

Pattern of triptans use: a retrospective prescription study in Calabria, Italy.

Neural Regen Res 2020 Jul;15(7):1340-1343

School of Hospital Pharmacy; Department of Health Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy.

Triptans are 5-hydroxytryptamine 1B/1D receptor agonists used in moderate to severe migraine attacks as first line when non-specific, symptomatic, nonsteroidal anti-inflammatory drugs are not effective. To gain insight in the treatment of migraine in the regional context, this retrospective (from January to August of the years 2017 and 2018) study aimed at monitoring the use of triptans approved by the regional health authority in Calabria. The data demonstrate that the overall treatment of migraine with triptans in the different provinces of Calabria falls in the average regional prescription/dispensation. Interestingly, Crotone showed a trend to an increased amount of defined daily dose/1000 inhabitants per day. The present analysis might stand for homogeneity of treatment of migraineurs in Calabria and highlights the need for better understanding the apparent differences in the local pattern of almotriptan use to improve the appropriateness.
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http://dx.doi.org/10.4103/1673-5374.272630DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7047800PMC
July 2020

Anxiolytic-Like Effects of Bergamot Essential Oil Are Insensitive to Flumazenil in Rats.

Evid Based Complement Alternat Med 2019 14;2019:2156873. Epub 2019 Aug 14.

Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy.

Anxiety disorders are one of the most common mental disorders, and benzodiazepines (BDZs), acting on gamma-aminobutyric acid type A (GABA-A) receptor complex, represent the most common antianxiety medications in the world. However, chronic BDZ use elicits several adverse reactions. Reportedly, aromatherapy is safer for the management of anxiety. Bergamot essential oil (BEO) extracted from Risso Poiteau fruit, like other essential oils, is widely used in aromatherapy to relieve symptoms of stress-induced anxiety. Interestingly, preclinical data indicate that BEO induces anxiolytic-like/relaxant effects in animal behavioural tasks not superimposable to those of benzodiazepine diazepam. To better elucidate the involvement of GABAergic transmission, the present study examines the effects of pretreatment with flumazenil (FLZ), a benzodiazepine site antagonist, on BEO effects using open-field task (OFT) in rats. The data yielded show that FLZ does not significantly affect behavioural effects of the phytocomplex. These results demonstrate the lack of overlapping between BEO and BDZ behavioural effects, contributing to the characterization of the neurobiological profile of the essential oil for its rational use in aromatherapy.
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http://dx.doi.org/10.1155/2019/2156873DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710760PMC
August 2019

New Trends in Migraine Pharmacology: Targeting Calcitonin Gene-Related Peptide (CGRP) With Monoclonal Antibodies.

Front Pharmacol 2019 9;10:363. Epub 2019 Apr 9.

Department of Health Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy.

Migraine is a common neurologic disorder characterized by attacks consisting of unilateral, throbbing headache accompanied by photophobia, phonophobia, and nausea which remarkably reduces the patients' quality of life. Not migraine-specific non-steroidal anti-inflammatory drugs (NSAIDs) are effective in patients affected by mild episodic migraine whilst in moderate or severe episodic migraine and in chronic migraineurs triptans and preventative therapies are needed. Since these treatments are endowed with serious side effects and have limited effectiveness new pharmacological approaches have been investigated. The demonstrated pivotal role of calcitonin gene-related peptide (CGRP) has fostered the development of CGRP antagonists, unfortunately endowed with liver toxicity, and monoclonal antibodies (mAbs) toward circulating CGRP released during migraine attack or targeting its receptor. Currently, four mAbs, eptinezumab, fremanezumab, galcanezumab for CGRP and erenumab for CGRP canonical receptor, have been studied in clinical trials for episodic and chronic migraine. Apart from the proven effectiveness, these antibodies have resulted well tolerated and could improve the compliance of the patients due to their long half-lives allowing less frequent administrations. This study aims at investigating the still poorly clear pathogenesis of migraine and the potential role of anti-CGRP mAbs in the scenario of prophylaxis of migraine.
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http://dx.doi.org/10.3389/fphar.2019.00363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6465320PMC
April 2019

The tricyclic antidepressant clomipramine inhibits neuronal autophagic flux.

Sci Rep 2019 03 19;9(1):4881. Epub 2019 Mar 19.

German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.

Antidepressants are commonly prescribed psychotropic substances for the symptomatic treatment of mood disorders. Their primary mechanism of action is the modulation of neurotransmission and the consequent accumulation of monoamines, such as serotonin and noradrenaline. However, antidepressants have additional molecular targets that, through multiple signaling cascades, may ultimately alter essential cellular processes. In this regard, it was previously demonstrated that clomipramine, a widely used FDA-approved tricyclic antidepressant, interferes with the autophagic flux and severely compromises the viability of tumorigenic cells upon cytotoxic stress. Consistent with this line of evidence, we report here that clomipramine undermines autophagosome formation and cargo degradation in primary dissociated neurons. A similar pattern was observed in the frontal cortex and liver of treated mice, as well as in the nematode Caenorhabditis elegans exposed to clomipramine. Together, our findings indicate that clomipramine may negatively regulate the autophagic flux in various tissues, with potential metabolic and functional implications for the homeostatic maintenance of differentiated cells.
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http://dx.doi.org/10.1038/s41598-019-40887-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6424961PMC
March 2019

Neuroinflammation as a target for glaucoma therapy.

Neural Regen Res 2019 Mar;14(3):391-394

Visual Neurophysiology and Neurophthalmology Research Unit, IRCCS G.B. Bietti Foundation, Roma, Italy.

The pathogenesis of glaucoma is still not fully clarified but a growing body of evidence suggests that neuroinflammation and immune response are part of the sequence of pathological events leading to the optic neuropathy. Indeed, inflammation - involving the activation and proliferation of resident glial cells (astrocytes, Muller cells and microglia) and the release of a plethora of anti- and pro-inflammatory cytokines, chemokines and reactive oxygen species - has been reported as common features in clinical and experimental glaucoma. In the insulted retina, as for other neuronal tissues, pathogenic and reparative aspects coexist in the inflammatory process, with extent and persistency affecting the final outcome. In view of this, therapies aimed at modulating the immune and inflammatory responses may represent a promising approach for limiting the optic nerve damage and the loss of retinal ganglion cells associated with glaucoma.
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http://dx.doi.org/10.4103/1673-5374.245465DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6334605PMC
March 2019

Rapamycin and fasting sustain autophagy response activated by ischemia/reperfusion injury and promote retinal ganglion cell survival.

Cell Death Dis 2018 09 24;9(10):981. Epub 2018 Sep 24.

Ophtalmology Unit, Department of Experimental Medicine, University of Rome "Tor Vergata", 00133, Rome, Italy.

Autophagy, the cellular process responsible for degradation and recycling of cytoplasmic components through the autophagosomal-lysosomal pathway, is fundamental for neuronal homeostasis and its deregulation has been identified as a hallmark of neurodegeneration. Retinal hypoxic-ischemic events occur in several sight-treating disorders, such as central retinal artery occlusion, diabetic retinopathy, and glaucoma, leading to degeneration and loss of retinal ganglion cells. Here we analyzed the autophagic response in the retinas of mice subjected to ischemia induced by transient elevation of intraocular pressure, reporting a biphasic and reperfusion time-dependent modulation of the process. Ischemic insult triggered in the retina an acute induction of autophagy that lasted during the first hours of reperfusion. This early upregulation of the autophagic flux limited RGC death, as demonstrated by the increased neuronal loss observed in mice with genetic impairment of basal autophagy owing to heterozygous ablation of the autophagy-positive modulator Ambra1 (Ambra1). Upregulation of autophagy was exhausted 24 h after the ischemic event and reduced autophagosomal turnover was associated with build up of the autophagic substrate SQSTM-1/p62, decreased ATG12-ATG5 conjugate, ATG4 and BECN1/Beclin1 expression. Animal fasting or subchronic systemic treatment with rapamycin sustained and prolonged autophagy activation and improved RGC survival, providing proof of principle for autophagy induction as a potential therapeutic strategy in retinal neurodegenerative conditions associated with hypoxic/ischemic stresses.
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http://dx.doi.org/10.1038/s41419-018-1044-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6155349PMC
September 2018

Dibutyryl cAMP- or Interleukin-6-induced astrocytic differentiation enhances mannose binding lectin (MBL)-associated serine protease (MASP)-1/3 expression in C6 glioma cells.

Arch Biochem Biophys 2018 09 28;653:39-49. Epub 2018 Jun 28.

Dipartimento di Scienze Motorie e del Benessere, Università degli Studi di Napoli "Parthenope", Via Medina, 40, Napoli, 80133, Italy; CEINGE, Biotecnologie Avanzate, S.C. a R.L., Via G. Salvatore 486, 80145, Napoli, Italy. Electronic address:

Mannose-binding lectin (MBL)-Associated Serine Proteases (MASP)-1 and 3, key enzymes in the lectin complement pathway of innate immune response, are also expressed in glioma cell lines. We investigated MASP-1 and MASP-3 expression during dibutyryl cyclic AMP (dbcAMP)- or Interleukin-6 (rIL-6)-induced astrocytic differentiation of C6 glioma cells. Our results demonstrate that C6 cells express basal levels of MASP-1 and MASP-3 and following exposure to dbcAMP or IL-6, a consistent MASP-1 and MASP-3 mRNA up-regulation was found, with a behavior similar to that showed by the fibrillary acidic protein (GFAP). Furthermore, in cell conditioned media, rIL-6 stimulated MASP-3 secretion which reached levels similar to those obtained by dbcAMP treatment. Moreover, the detection of a 46-kDa MASP-3 suggested its processing to the mature form in the extracellular cell medium. Interestingly, the H89 PKA inhibitor, mostly affected dbcAMP-induced MASP-1 and MASP-3 mRNA levels, compared to that of rIL-6, suggesting that cAMP/PKA pathway contributes to MASP-1 and MASP-3 up-regulation. MASP-1 and MASP-3 expression increase was concomitant with dbcAMP- or rIL-6-induced phosphorylation of STAT3. Our findings suggest that the increase in intracellular cAMP concentration or rIL-6 stimulation can play a role in innate immunity enhancing MASP-1 and MASP-3 expression level in C6 glioma cells.
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http://dx.doi.org/10.1016/j.abb.2018.06.016DOI Listing
September 2018

Early LC3 lipidation induced by d-limonene does not rely on mTOR inhibition, ERK activation and ROS production and it is associated with reduced clonogenic capacity of SH-SY5Y neuroblastoma cells.

Phytomedicine 2018 Feb;40:98-105

Department of Health Sciences, University "Magna Graecia" of Catanzaro, Campus Universitario "Salvatore Venuta", V Livello Edificio delle Bioscienze, Viale Europa, 88100 Catanzaro, Italy. Electronic address:

Background: d-Limonene is a natural monoterpene abundant in Citrus essential oils. It is endowed with several biological activities, including inhibition of carcinogenesis and promotion of tumour regression. Recently, d-limonene has been shown to modulate autophagic markers in vitro at concentrations found in vivo, in clinical pharmacokinetic studies. Autophagy is an intracellular catabolic process serving as both an adaptive metabolic response and a quality control mechanism. Because autophagy defects have been linked to a wide range of human pathologies, including neurodegeneration and cancer, there is a need for new pharmacological tools to control deregulated autophagy.

Purpose: To better understand the effects of d-limonene on autophagy, to identify the molecular mechanisms through which this monoterpene rapidly triggers LC3 lipidation and to evaluate the role for autophagy in long-term effects of d-limonene.

Methods: Human SH-SY5Y neuroblastoma, HepG2 hepatocellular carcinoma and MCF7 breast cancer cells were used. Endogenous LC3-II levels were evaluated by western blotting. Autophagic flux assay was performed using bafilomycin A1 and chloroquine. Intracellular distribution of LC3 protein was studied by confocal microscopy analysis of LC3B-GFP transduced cells. Expression of lysosomal-membrane protein LAMP-1 was assessed by immunofluorescence analysis. Phosphorylated levels of downstream substrates of mTOR kinase (p70S6 kinase, 4E-BP1, and ULK1) and ERK were analyzed by western blotting. Production of reactive oxygen species (ROS) was assessed by live confocal microscopy of cells loaded with CellROX Green Reagent. Clonogenic assay was used to evaluate the ability of treated cells to proliferate and form colonies.

Results: LC3 lipidation promoted by d-limonene correlates with autophagosome formation and stimulation of basal autophagy. LC3 lipidation does not rely on inhibition of mTOR kinase, which instead appears to be transiently activated. In addition, d-limonene rapidly activates ERK and stimulates ROS generation, yet none of these events is implicated in lipidation of LC3, which was only partly reduced by chelation of intracellular calcium. The early LC3 lipidation induced by d-limonene is associated with inhibition of clonogenic capacity which is reverted by the autophagy inhibitor chloroquine.

Conclusions: d-Limonene rapidly stimulates the autophagic flux in cultured cancer cells, which could be usefully exploited for therapeutic purposes.
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http://dx.doi.org/10.1016/j.phymed.2018.01.005DOI Listing
February 2018

Post-ischemic treatment with azithromycin protects ganglion cells against retinal ischemia/reperfusion injury in the rat.

Mol Vis 2017 11;23:911-921. Epub 2017 Dec 11.

Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, Arcavacata di Rende, Italy.

Purpose: Retinal ischemic phenomena occur in several ocular diseases that share the degeneration and death of retinal ganglion cells (RGCs) as the final event. We tested the neuroprotective effect of azithromycin, a widely used semisynthetic macrolide antibiotic endowed with anti-inflammatory and immunomodulatory properties, in a model of retinal ischemic injury induced by transient elevation of intraocular pressure in the rat.

Methods: Retinal ischemia was induced in adult rats with transient elevation of intraocular pressure. RGCs were retrogradely labeled with Fluoro-Gold, and survival was assessed following a single dose of azithromycin given systemically at the end of the ischemia. The expression of death-associated proteins and extracellular signal-regulated kinase (ERK) activation was studied with western blotting. Expression and activity of matrix metalloproteinase-2 (MMP-2) and -9 were analyzed with gelatin zymography.

Results: Acute post-injury administration of azithromycin significantly prevented RGC death. This effect was accompanied by reduced calpain activity and prevention of Bcl-2-associated death promoter (Bad) upregulation. The observed neuroprotection was associated with a significant inhibition of MMP-2/-9 gelatinolytic activity and ERK1/2 phosphorylation.

Conclusions: Azithromycin provides neuroprotection by modifying the inflammatory state of the retina following ischemia/reperfusion injury suggesting potential for repurposing as a drug capable of limiting or preventing retinal neuronal damage.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5741380PMC
May 2018

Rational Basis for Nutraceuticals in the Treatment of Glaucoma.

Curr Neuropharmacol 2018 ;16(7):1004-1017

Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Calabria, Italy.

Background: Glaucoma, the second leading cause of blindness worldwide, is a chronic optic neuropathy characterized by progressive retinal ganglion cell (RGC) axons degeneration and death. Primary open-angle glaucoma (OAG), the most common type, is often associated with increased intraocular pressure (IOP), however other factors have been recognized to partecipate to the patogenesis of the optic neuropathy. IOP-independent mechanisms that contribute to the glaucoma-related neurodegeneration include oxidative stress, excitotoxicity, neuroinflammation, and impaired ocular blood flow. The involvement of several and diverse factors is one of the reasons for the progression of glaucoma observed even under efficient IOP control with the currently available drugs.

Methods: Current research and online content related to the potential of nutritional supplements for limiting retinal damage and improving RGC survival is reviewed.

Results: Recent studies have suggested a link between dietary factors and glaucoma risk. Particularly, some nutrients have proven capable of lowering IOP, increase circulation to the optic nerve, modulate excitotoxicity and promote RGC survival. However, the lack of clinical trials limit their current therapeutic use. The appropriate use of nutraceuticals that may be able to modify the risk of glaucoma may provide insight into glaucoma pathogenesis and decrease the need for, and therefore the side effects from, conventional therapies.

Conclusion: The effects of nutrients with anti-oxidant and neuroprotective properties are of great interest and nutraceuticals may offer some therapeutic potential although a further rigorous evaluation of nutraceuticals in the treatment of glaucoma is needed to determine their safety and efficacy.
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http://dx.doi.org/10.2174/1570159X15666171109124520DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6120110PMC
October 2018

Retinal ganglion cell death in glaucoma: Exploring the role of neuroinflammation.

Eur J Pharmacol 2016 Sep 1;787:134-42. Epub 2016 Apr 1.

Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy; University Center for Adaptive Disorders and Head Pain, Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Arcavacata di Rende, Italy.

In clinical glaucoma, as well as in experimental models, the loss of retinal ganglion cells occurs by apoptosis. This final event is preceded by inflammatory responses involving the activation of innate and adaptive immunity, with retinal and optic nerve resident glial cells acting as major players. Here we review the current literature on the role of neuroinflammation in neurodegeneration, focusing on the inflammatory molecular mechanisms involved in the pathogenesis and progression of the optic neuropathy.
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http://dx.doi.org/10.1016/j.ejphar.2016.03.064DOI Listing
September 2016

Caspase-1-independent Maturation of IL-1β in Ischemic Brain Injury: is there a Role for Gelatinases?

Mini Rev Med Chem 2016 ;16(9):729-37

Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, via P. Bucci, ed. Polifunzionale, 87036, Rende (CS), Italy.

Ischemic stroke is a devastating condition primarily caused by reduced blood supply to the brain. Interleukin (IL)-1β is a pro-inflammatory cytokine that plays a pivotal role in the detrimental inflammatory processes that participate to cerebral ischemic damage. After injury, it is produced by distinct cells of the neurovascular unit as an inactive precursor, pro-IL-1β. Although previous studies have suggested that caspase-1 is the main enzyme implicated in the cleavage of pro-IL-1β into the biologically active cytokine, recent work has demonstrated that, under ischemia-reperfusion conditions, other mechanisms may be involved in cytokine maturation. Indeed, we have shown that in rats subjected to transient middle cerebral artery occlusion (MCAo), elevation of IL-1β levels is paralleled by an elevation of gelatinolytic, but not caspase-1 activity in the injured hemisphere and pharmacological inhibition of gelatinases, i.e. matrix metalloproteases (MMP)-2 and MMP-9 prevents cytokine maturation. These findings further support the hypothesis that, under ischemia-reperfusion injury, cerebral elevation of IL-1β occurs via mechanisms other than caspase-1, likely involving gelatinases.
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http://dx.doi.org/10.2174/1389557516666160321112512DOI Listing
December 2016

Intravitreal injection of forskolin, homotaurine, and L-carnosine affords neuroprotection to retinal ganglion cells following retinal ischemic injury.

Mol Vis 2015 29;21:718-29. Epub 2015 Jun 29.

Ophtalmology Unit, Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata" Rome, Italy.

Purpose: Retinal ganglion cell (RGC) death is the final event leading to visual impairment in glaucoma; therefore, identification of neuroprotective strategies able to slow down or prevent the process is one of the main challenges for glaucoma research. The purpose of this study was to evaluate the neuroprotective potential of RGC death induced by the in vivo transient increase in intraocular pressure (IOP) of a combined treatment with forskolin, homotaurine, and L-carnosine. Forskolin (7beta-acetoxy-8, 13-epoxy-1a, 6β, 9a-trihydroxy-labd-14-en-11-one) is an activator of adenylate cyclase that decreases IOP by reducing aqueous humor production and functions as a neuroprotector due to its neurotrophin-stimulating activity. Homotaurine is a natural aminosulfonate compound endowed with neuromodulatory effects, while the dipeptide L-carnosine is known for its antioxidant properties.

Methods: Retinal ischemia was induced in the right eye of adult male Wistar rats by acutely increasing the IOP. Forskolin, homotaurine, and L-carnosine were intravitreally injected and RGC survival evaluated following retrograde labeling with FluoroGold. Total and phosphorylated Akt and glycogen synthase kinase-3β (GSK-3β) protein levels, as well as calpain activity, were analyzed with western blot. Protein kinase A (PKA) was inhibited by intravitreal injection of H89.

Results: A synergic neuroprotective effect on RGC survival was observed following the combined treatment with forskolin, homotaurine, and L-carnosine compared to forskolin alone. The observed neuroprotection was associated with reduced calpain activity, upregulation of phosphoinositide 3-kinase (PI3K)/Akt pathway, and inhibition of GSK-3β but was independent from PKA activation and distinct from the hypotensive effects of forskolin.

Conclusions: A multidrug/multitarget approach, by interfering with several pathways involved in RGC degeneration, may be promising to achieve glaucoma neuroprotection.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4483367PMC
April 2016

Role of D-Limonene in autophagy induced by bergamot essential oil in SH-SY5Y neuroblastoma cells.

PLoS One 2014 24;9(11):e113682. Epub 2014 Nov 24.

Department of Health Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy.

Bergamot (Citrus bergamia, Risso et Poiteau) essential oil (BEO) is a well characterized, widely used plant extract. BEO exerts anxiolytic, analgesic and neuroprotective activities in rodents through mechanisms that are only partly known and need to be further investigated. To gain more insight into the biological effects of this essential oil, we tested the ability of BEO (0.005-0.03%) to modulate autophagic pathways in human SH-SY5Y neuroblastoma cells. BEO-treated cells show increased LC3II levels and appearance of dot-like formations of endogenous LC3 protein that colocalize with the lysosome marker LAMP-1. Autophagic flux assay using bafilomycin A1 and degradation of the specific autophagy substrate p62 confirmed that the observed increase of LC3II levels in BEO-exposed cells is due to autophagy induction rather than to a decreased autophagosomal turnover. Induction of autophagy is an early and not cell-line specific response to BEO. Beside basal autophagy, BEO also enhanced autophagy triggered by serum starvation and rapamycin indicating that the underlying mechanism is mTOR independent. Accordingly, BEO did not affect the phosphorylation of ULK1 (Ser757) and p70(S6K) (Thr389), two downstream targets of mTOR. Furthermore, induction of autophagy by BEO is beclin-1 independent, occurs in a concentration-dependent manner and is unrelated to the ability of BEO to induce cell death. In order to identify the active constituents responsible for these effects, the two most abundant monoterpenes found in the essential oil, d-limonene (125-750 µM) and linalyl acetate (62.5-375 µM), were individually tested at concentrations comparable to those found in 0.005-0.03% BEO. The same features of stimulated autophagy elicited by BEO were reproduced by D-limonene, which rapidly increases LC3II and reduces p62 levels in a concentration-dependent manner. Linalyl acetate was ineffective in replicating BEO effects; however, it greatly enhanced LC3 lipidation triggered by D-limonene.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0113682PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4242674PMC
January 2016

Protease Nexin-1 affects the migration and invasion of C6 glioma cells through the regulation of urokinase Plasminogen Activator and Matrix Metalloproteinase-9/2.

Biochim Biophys Acta 2014 Nov 27;1843(11):2631-44. Epub 2014 Jul 27.

Dipartimento di Scienze Motorie e del Benessere, Università di Napoli "Parthenope", Via Medina 40, 80133 Napoli, Italy; CEINGE, Biotecnologie Avanzate, S.C. a R.L., Via G. Salvatore 486, 80145 Napoli, Italy. Electronic address:

Protease Nexin-1 (PN-1) or Serpine2 is a physiological regulator of extracellular proteases as thrombin and urokinase (uPA) in the brain. Besides, PN-1 is also implicated in some human cancers and further identified as a substrate for Matrix Metalloproteinase (MMP)-9, a key enzyme in tumor invasiveness. Our aim was to study the role of PN-1 in the migration and invasive potential of glioma cells, using the rat C6 glioma cell line as stable clones transfected with pAVU6+27 vector expressing PN-1 short-hairpin RNA. We find that PN-1 knockdown enhanced the in vitro migration and invasiveness of C6 cells which also showed a strong gelatinolytic activity by in situ zymography. PN-1 silencing did not alter prothrombin whereas increased uPA, MMP-9 and MMP-2 expression levels and gelatinolytic activity in a conditioned medium from stable C6 cells. Selective inhibitors for MMP-9 (Inhibitor I), MMP-2 (Inhibitor III) or exogenous recombinant PN-1 added to the culture medium of C6 silenced cells restored either the migration and invasive ability or gelatinolytic activity thus validating the specificity of PN-1 silencing strategy. Phosphorylation levels of extracellular signal-related kinases (Erk1/2 and p38 MAPK) involved in MMP-9 and MMP-2 signaling were increased in PN-1 silenced cells. This study shows that PN-1 affects glioma cell migration and invasiveness through the regulation of uPA and MMP-9/2 expression levels which contribute to the degradation of extracellular matrix during tumor invasion.
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http://dx.doi.org/10.1016/j.bbamcr.2014.07.008DOI Listing
November 2014

Polychlorinated biphenyls impair dibutyryl cAMP-induced astrocytic differentiation in rat C6 glial cell line.

FEBS Open Bio 2013 29;3:459-66. Epub 2013 Oct 29.

Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Via P. Bucci, Arcavacata di Rende, Cosenza (CS) 87036, Italy.

In the central nervous system, alteration of glial cell differentiation can affect brain functions. Polychlorinated biphenyls (PCBs) are persistent environmental chemical contaminants that exert neurotoxic effects in glial and neuronal cells. We examined the effects of a commercial mixture of PCBs, Aroclor1254 (A1254) on astrocytic differentiation of glial cells, using the rat C6 cell line as in vitro model. The exposure for 24 h to sub-toxic concentrations of A1254 (3 or 9 μM) impaired dibutyryl cAMP-induced astrocytic differentiation as showed by the decrease of glial fibrillary acidic protein (GFAP) protein levels and inhibition in change of cell morphology toward an astrocytic phenotype. The A1254 inhibition was restored by the addition of a protein kinase C (PKC) inhibitor, bisindolylmaleimide (bis), therefore indicating that PCBs disturbed the cAMP-induced astrocytic differentiation of C6 cells via the PKC pathway. The phosphorylation of signal transducer and activator of transcription 3 (STAT3) is essential for cAMP-induced transcription of GFAP promoter in C6 cells. Our results indicated that the exposure to A1254 (3 or 9 μM) for 24 h suppressed cAMP-induced STAT3 phosphorylation. Moreover, A1254 reduced cAMP-dependent phosphorylation of STAT3 requires inhibition of PKC activity. Together, our results suggest that PCBs induce perturbation in cAMP/PKA and PKC signaling pathway during astrocytic differentiation of glial cells.
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http://dx.doi.org/10.1016/j.fob.2013.10.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3829991PMC
November 2013

NCX3 regulates mitochondrial Ca(2+) handling through the AKAP121-anchored signaling complex and prevents hypoxia-induced neuronal death.

J Cell Sci 2013 Dec 7;126(Pt 24):5566-77. Epub 2013 Oct 7.

Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples-National Institute of Neuroscience, Italy.

The mitochondrial influx and efflux of Ca(2+) play a relevant role in cytosolic and mitochondrial Ca(2+) homeostasis, and contribute to the regulation of mitochondrial functions in neurons. The mitochondrial Na(+)/Ca(2+) exchanger, which was first postulated in 1974, has been primarily investigated only from a functional point of view, and its identity and localization in the mitochondria have been a matter of debate over the past three decades. Recently, a Li(+)-dependent Na(+)/Ca(2+) exchanger extruding Ca(2+) from the matrix has been found in the inner mitochondrial membrane of neuronal cells. However, evidence has been provided that the outer membrane is impermeable to Ca(2+) efflux into the cytoplasm. In this study, we demonstrate for the first time that the nuclear-encoded NCX3 isoform (1) is located on the outer mitochondrial membrane (OMM) of neurons; (2) colocalizes and immunoprecipitates with AKAP121 (also known as AKAP1), a member of the protein kinase A anchoring proteins (AKAPs) present on the outer membrane; (3) extrudes Ca(2+) from mitochondria through AKAP121 interaction in a PKA-mediated manner, both under normoxia and hypoxia; and (4) improves cell survival when it works in the Ca(2+) efflux mode at the level of the OMM. Collectively, these results suggest that, in neurons, NCX3 regulates mitochondrial Ca(2+) handling from the OMM through an AKAP121-anchored signaling complex, thus promoting cell survival during hypoxia.
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http://dx.doi.org/10.1242/jcs.129668DOI Listing
December 2013

Impairment of neuronal glutamate uptake and modulation of the glutamate transporter GLT-1 induced by retinal ischemia.

PLoS One 2013 6;8(8):e69250. Epub 2013 Aug 6.

Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy.

Excitotoxicity has been implicated in the retinal neuronal loss in several ocular pathologies including glaucoma. Dysfunction of Excitatory Amino Acid Transporters is often a key component of the cascade leading to excitotoxic cell death. In the retina, glutamate transport is mainly operated by the glial glutamate transporter GLAST and the neuronal transporter GLT-1. In this study we evaluated the expression of GLAST and GLT-1 in a rat model of acute glaucoma based on the transient increase of intraocular pressure (IOP) and characterized by high glutamate levels during the reperfusion that follows the ischemic event associated with raised IOP. No changes were reported in GLAST expression while, at neuronal level, a reduction of glutamate uptake and of transporter reversal-mediated glutamate release was observed in isolated retinal synaptosomes. This was accompanied by modulation of GLT-1 expression leading to the reduction of the canonical 65 kDa form and upregulation of a GLT-1-related 38 kDa protein. These results support a role for neuronal transporters in glutamate accumulation observed in the retina following an ischemic event and suggest the presence of a GLT-1 neuronal new alternative splice variant, induced in response to the detrimental stimulus.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0069250PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3735546PMC
April 2014

In search of new targets for retinal neuroprotection: is there a role for autophagy?

Curr Opin Pharmacol 2013 Feb 1;13(1):72-7. Epub 2012 Oct 1.

Department of Pharmacobiology, University of Calabria, Arcavacata di Rende, Italy.

Autophagy is a highly conserved catabolic pathway in which proteins and organelles are engulfed by vacuoles that are targeted to lysosomes for degradation. Defects in the autophagic machinery have been described in several neurodegenerative diseases uncovering the tight dependency of neuronal survival on the efficiency of the autophagic process. Despite the large amount of literature investigating autophagy in a number of pathological conditions our knowledge of its role in glaucoma neurodegeneration is just beginning. However, recent experimental data revealing that autophagy modulation occurs in retinal ganglion cells (RGCs) under glaucoma-related stressing conditions support the hypothesis that dysfunctional autophagy might underlie the process leading to RGC death. Although our understanding of the role of autophagy in glaucoma is still developing, there is the possibility that neuroprotection may be achieved by modulating autophagy. This would be a promising approach as it could lead to the much-sought development of alternative therapeutic strategies to prevent visual loss in glaucoma.
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http://dx.doi.org/10.1016/j.coph.2012.09.004DOI Listing
February 2013

Early and late events induced by polyQ-expanded proteins: identification of a common pathogenic property of polYQ-expanded proteins.

J Biol Chem 2011 Feb 28;286(6):4727-41. Epub 2010 Nov 28.

Department of Molecular and Cellular Biology and Pathology, School of Medicine, Federico II University of Naples, Naples 80131 Italy.

To find a common pathogenetic trait induced by polyQ-expanded proteins, we have used a conditional expression system in PC12 cells to tune the expression of these proteins and analyze the early and late consequences of their expression. We find that expression for 3 h of a polyQ-expanded protein stimulates cellular reactive oxygen species (ROS) levels and significantly reduces the mitochondrial electrochemical gradient. 24-36 h later, ROS induce DNA damage and activation of the checkpoint kinase, ATM. DNA damage signatures are reversible and persist as long as polyQ-expanded proteins are expressed. Transcription of neural and stress response genes is down-regulated in these cells. Selective inhibition of ATM or histone deacetylase rescues transcription and restores the expression of silenced genes. Eventually, after 1 week, the expression of polyQ-expanded protein also induces endoplasmic reticulum stress. As to the primary mechanism responsible for ROS generation, we find that polyQ-expanded proteins, including native Ataxin-2 and Huntingtin, are selectively sequestered in the lipid raft membrane compartment and interact with gp91, the membrane NADPH-oxidase subunit. Selective inhibition of NADPH oxidase or silencing of H-Ras signaling dissolves the aggregates and eliminates DNA damage. We suggest that targeting of the polyQ-expanded proteins to the lipid rafts activates the resident NADPH oxidase. This triggers a signal linking H-Ras, ROS, and ERK1/2 that maintains and propagates the ROS wave to the nucleus. This mechanism may represent the common pathogenetic signature of all polyQ-expanded proteins independently of the specific context or the function of the native wild type protein.
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http://dx.doi.org/10.1074/jbc.M110.156521DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3039353PMC
February 2011

Cigarette smoke condensate causes a decrease of the gene expression of Cu-Zn superoxide dismutase, Mn superoxide dismutase, glutathione peroxidase, catalase, and free radical-induced cell injury in SH-SY5Y human neuroblastoma cells.

Neurotox Res 2011 Jan 1;19(1):49-54. Epub 2009 Dec 1.

Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via S. Pansini 5, 80131 Naples, Italy.

Cigarette smoking condensate (CSC) contains oxidant compounds able to generate superoxide. The aim of the present study was to investigate the effect of the exposure to CSC on: (1) free radical production, (2) the gene expression of the antioxidant enzymes Cu-Zn superoxide dismutase (SOD1), Mn superoxide dismutase (SOD2), Glutathione Peroxidase (GPx), and catalase (CAT), and (3) cell survival in human neuroblastoma SH-SY5Y cells. The results showed that exposure (24 h) to different concentrations (10-150 μg/ml) of CSC caused a dose dependent cell injury that was coupled to the maximal increase of free radical production. These events were prevented by the addition to the incubation medium of the scavenger Vitamin E (50 μM). Furthermore, CSC exposure caused a reduction of the gene expression of the antioxidant enzymes SOD1, SOD2, GPx, and CAT that was counteracted by Vitamin E (50 μM). These results suggest that CSC exposure can induce a free radical overcharge that may be responsible for the inhibition of antioxidant enzymes expression and cell injury in SH-SY5Y human neuroblastoma cells. In fact the scavenger vitamin E can block both cell injury and inhibition of SOD1, SOD2, GPx, and CAT induced by CSC exposure.
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http://dx.doi.org/10.1007/s12640-009-9138-6DOI Listing
January 2011

Anoxia-induced NF-kappaB-dependent upregulation of NCX1 contributes to Ca2+ refilling into endoplasmic reticulum in cortical neurons.

Stroke 2009 Mar 22;40(3):922-9. Epub 2009 Jan 22.

Fondazione IRCCS SDN, Naples, Italy.

Background And Purpose: The 3 gene products of the Na(+)/Ca(2+) exchanger (NCX), viz, NCX1, NCX2, and NCX3, may play a pivotal role in the pathophysiology of brain ischemia. The aim of this study was to investigate the transductional and posttranslational mechanisms involved in the expression of these isoforms during oxygen and glucose deprivation and their role in endoplasmic reticulum Ca(2+) refilling in cortical neurons.

Methods: NCX1, NCX2, and NCX3 transcript and protein expression was evaluated in primary cortical neurons by reverse transcriptase-polymerase chain reaction and Western blot. NCX currents (I(NCX)) and cytosolic Ca(2+) concentrations ([Ca(2+)](i)) were monitored by means of patch-clamp in whole-cell configuration and Fura-2AM single-cell video imaging, respectively.

Results: Exposure of cortical neurons to 3 hours of oxygen and glucose deprivation yielded dissimilar effects on the 3 isoforms. First, it induced an upregulation in NCX1 transcript and protein expression. This change was exerted at the transcriptional level because the inhibition of nuclear factor kappa B translocation by small interfering RNA against p65 and SN-50 prevented oxygen and glucose deprivation-induced NCX1 upregulation. Second, it elicited a downregulation of NCX3 protein expression. This change, unlike NCX1, was exerted at the posttranscriptional level because it was prevented by the proteasome inhibitor MG-132. Finally, we found that it significantly increased I(NCX) both in the forward and reverse modes of operation and promoted an increase in ER Ca(2+) accumulation. Interestingly, such accumulation was prevented by the silencing of NCX1 and the NCX inhibitor CB-DMB that triggered caspase-12 activation.

Conclusions: These results suggest that nuclear factor kappa B-dependent NCX1 upregulation may play a fundamental role in Ca(2+) refilling in the endoplasmic reticulum, thus helping neurons to prevent endoplasmic reticulum stress during oxygen and glucose deprivation.
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http://dx.doi.org/10.1161/STROKEAHA.108.531962DOI Listing
March 2009

Proteolysis of AKAP121 regulates mitochondrial activity during cellular hypoxia and brain ischaemia.

EMBO J 2008 Apr 6;27(7):1073-84. Epub 2008 Mar 6.

Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università Federico II, Naples, Italy.

A-kinase anchor protein 121 (AKAP121) assembles a multivalent signalling complex on the outer mitochondrial membrane that controls persistence and amplitude of cAMP and src signalling to mitochondria, and plays an essential role in oxidative metabolism and cell survival. Here, we show that AKAP121 levels are regulated post-translationally by the ubiquitin/proteasome pathway. Seven In-Absentia Homolog 2 (Siah2), an E3-ubiquitin ligase whose expression is induced in hypoxic conditions, formed a complex and degraded AKAP121. In addition, we show that overexpression of Siah2 or oxygen and glucose deprivation (OGD) promotes Siah2-mediated ubiquitination and proteolysis of AKAP121. Upregulation of Siah2, by modulation of the cellular levels of AKAP121, significantly affects mitochondrial activity assessed as mitochondrial membrane potential and oxidative capacity. Also during cerebral ischaemia, AKAP121 is degraded in a Siah2-dependent manner. These findings reveal a novel mechanism of attenuation of cAMP/PKA signaling, which occurs at the distal sites of signal generation mediated by proteolysis of an AKAP scaffold protein. By regulating the stability of AKAP121-signalling complex at mitochondria, cells efficiently and rapidly adapt oxidative metabolism to fluctuations in oxygen availability.
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http://dx.doi.org/10.1038/emboj.2008.33DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2323260PMC
April 2008

A critical role for the potassium-dependent sodium-calcium exchanger NCKX2 in protection against focal ischemic brain damage.

J Neurosci 2008 Feb;28(9):2053-63

Division of Pharmacology, Department of Neuroscience, School of Medicine, Federico II University of Naples, 80131 Naples, Italy.

The superfamily of cation/Ca2+ plasma-membrane exchangers contains two branches, the K+-independent Na+-Ca2+ exchangers (NCXs) and the K+-dependent Na+-Ca2+ exchangers (NCKXs), widely expressed in mammals. NCKX2 is the major neuronally expressed isoform among NCKX members. Despite its importance in maintaining Na+, Ca2+, and K+ homeostasis in the CNS, the role of NCKX2 during cerebral ischemia, a condition characterized by an alteration of ionic concentrations, has not yet been investigated. The present study examines NCKX2 role in the development of ischemic brain damage in permanent middle cerebral artery occlusion (pMCAO) and transient middle cerebral artery occlusion. Furthermore, to evaluate the effect of nckx2 ablation on neuronal survival, nckx2-/- primary cortical neurons were subjected to oxygen glucose deprivation plus reoxygenation. NCKX2 mRNA and protein expression was evaluated in the ischemic core and surrounding ipsilesional areas, at different time points after pMCAO in rats. In ischemic core and in periinfarctual area, NCKX2 mRNA and protein expression were downregulated. In addition, NCKX2 knock-down by antisense oligodeoxynucleotide and NCKX2 knock-out by genetic disruption dramatically increased infarct volume. Accordingly, nckx2-/- primary cortical neurons displayed a higher vulnerability and a greater [Ca2+]i increase under hypoxic conditions, compared with nckx2+/+ neurons. In addition, NCKX currents both in the forward and reverse mode of operation were significantly reduced in nckx2-/- neurons compared with nckx2+/+ cells. Overall, these results indicate that NCKX2 is involved in brain ischemia, and it may represent a new potential target to be investigated in the study of the molecular mechanisms involved in cerebral ischemia.
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http://dx.doi.org/10.1523/JNEUROSCI.4912-07.2008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6671846PMC
February 2008