Diabetic retinopathy, a major cause of vision loss, is currently treated with anti-VEGF agents. H... more Diabetic retinopathy, a major cause of vision loss, is currently treated with anti-VEGF agents. Here we tested two hypotheses: (i) high glucose damages retinal pericytes, the cell layer surrounding endothelial cells, via VEGF induction, which may be counteracted by anti-VEGFs and (ii) activation of PLA2/COX-2 pathway by high glucose might be upstream and/or downstream of VEGF in perycites, as previously observed in endothelial cells. Human retinal pericytes were treated with high glucose (25mM) for 48h and/or anti-VEGFs (40μg/ml aflibercept, 25μg/ml bevacizumab, 10μg/ml ranibizumab). All anti-VEGFs significantly prevented high glucose-induced cell damage (assessed by LDH release) and improved cell viability (assessed by MTT and Evans blue). High glucose-induced VEGF-A expression, as detected both at mRNA (qPCR) and protein (ELISA) level, while receptor (VEGFR1 and VEGFR2) expression, detected in control condition, was unaffected by treatments. High glucose induced also activation of PLA2/COX-2 pathway, as revealed by increased phosphorylation of cPLA2, COX-2 expression and PGE2 release. Treatment with cPLA2 (50μM AACOCF3) and COX-2 (5μM NS-392) inhibitors prevented both cell damage and VEGF-A induced by high glucose. Finally, challenge with exogenous VEGF-A (10ng/ml) induced VEGF-A expression, while anti-VEGFs reduced VEGF-A expression induced by either high glucose or exogenous VEGF-A. These data indicate that high glucose directly damages pericytes through activation of PLA2/COX-2/VEGF-A pathway. Furthermore, a kind of feed-forward loop between cPLA2/COX-2/PG axis and VEGF appears to operate in this system. Thus, anti-VEGFs afford protection of pericytes from high glucose by inhibiting this loop.
In recent years, efforts have been directed to develop "disease-modifying drugs" for Al... more In recent years, efforts have been directed to develop "disease-modifying drugs" for Alzheimer's disease (AD), i.e. drugs able to counteract the progression of AD. Because the earlier the treatment starts, the greater is the chance of success, it is crucial to develop reliable biomarkers for early detection of AD-related brain dysfunction, possibly before clinical onset. Disease-modifying drugs developed so far include drugs to reduce β amyloid (Aβ) production, drugs to prevent Aβ aggregation, drugs to promote Aβ clearance, drugs targeting tau phosphorylation and assembly, and other approaches. Active and passive immunotherapy is the main strategy aimed at increasing Aβ clearance. Unfortunately several candidate disease-modifying drugs have failed in phase III clinical trials conducted in mild to moderate AD. More recently, in phase III studies, bapineuzumab has been discontinued because it did not prove clinically effective (despite its significant effect on biomarker...
The International journal of social psychiatry, Jan 12, 2015
The aim was to measure the lifetime prevalence of panic disorder (PD) in an Italian community sam... more The aim was to measure the lifetime prevalence of panic disorder (PD) in an Italian community sample, and to estimate the burden attributable to PD in compromising the quality of life (QoL) of people diagnosed with it. Community survey was conducted on a sample of 4,999 randomly selected adult subjects. Instruments used were semi-structured clinical interview Advanced Neuropsychiatric Tools and Assessment Schedule (ANTAS), administered by clinicians and allowing diagnosis according to Diagnostic and Statistical Manual of Mental Disorder (4th ed.; DSM-IV); Short Form Health Survey (SF-12). The lifetime prevalence of PD was 3.6% (4.4% in females, 2.5% in males; p = .002). People with PD had a lower SF-12 score than the standardized community sample (35.5 ± 6.5 vs. 38.4 ± 5.9; p < .0001) with a mean difference (attributable burden) of 2.9 ± 0.7, that is, lower than PD with agoraphobia (AP; 4.2 ± 2.4). Wilson Disease (WD), Multiple Sclerosis, Major Depressive Disorder and Eating Diso...
PACAP and its cognate peptide VIP participate in various biological functions, including myelin m... more PACAP and its cognate peptide VIP participate in various biological functions, including myelin maturation and synthesis. However, defining whether these peptides affect peripheral expression of myelin proteins still remains unanswered. To address this issue, we assessed whether PACAP or VIP contribute to regulate the expression of three myelin proteins (MAG, MBP and MPZ, respectively) using the rat schwannoma cell line (RT4-P6D2T), a well-established model to study myelin gene expression. In addition, we endeavored to partly unravel the underlying molecular mechanisms involved. Expression of myelin-specific proteins was assessed in cells grown either in normal serum (10% FBS) or serum starved and treated with or without 100 nM PACAP or VIP. Furthermore, through pharmacological approach using the PACAP/VIP receptor antagonist (PACAP6-38) or specific pathway (MAPK or PI3K) inhibitors we defined the relative contribution of receptors and/or signaling pathways on the expression of myel...
The changing of omega-6/omega-3 polyunsaturated fatty acids (PUFA) in the food supply of Western ... more The changing of omega-6/omega-3 polyunsaturated fatty acids (PUFA) in the food supply of Western societies occurred over the last 150 years is thought to promote the pathogenesis of many inflammatory-related diseases, including depressive disorders. Several epidemiological studies reported a significant inverse correlation between intake of oily fish and depression or bipolar disorders. Studies conducted specifically on the association between omega-3 intake and depression reported contrasting results, suggesting that the preventive role of omega-3 PUFA may depend also on other factors, such as overall diet quality and the social environment. Accordingly, tertiary prevention with omega-3 PUFA supplement in depressed patients has reached greater effectiveness during the last recent years, although definitive statements on their use in depression therapy cannot be yet freely asserted. Among the biological properties of omega-3 PUFA, their anti-inflammatory effects and their important ...
Despite omega-3 polyunsaturated fatty acids (PUFA) supplementation in depressed patients have bee... more Despite omega-3 polyunsaturated fatty acids (PUFA) supplementation in depressed patients have been suggested to improve depressive symptomatology, previous findings are not univocal. To conduct an updated meta-analysis of randomized controlled trials (RCTs) of omega-3 PUFA treatment of depressive disorders, taking into account the clinical differences among patients included in the studies. A search on MEDLINE, EMBASE, PsycInfo, and the Cochrane Database of RCTs using omega-3 PUFA on patients with depressive symptoms published up to August 2013 was performed. Standardized mean difference in clinical measure of depression severity was primary outcome. Type of omega-3 used (particularly eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) and omega-3 as mono- or adjuvant therapy was also examined. Meta-regression analyses assessed the effects of study size, baseline depression severity, trial duration, dose of omega-3, and age of patients. Meta-analysis of 11 and 8 trials condu...
In this study, we report the design and synthesis of novel hybrids of caffeic acid phenetyl ester... more In this study, we report the design and synthesis of novel hybrids of caffeic acid phenetyl ester (CAPE) and non-steroidal anti-inflammatory drugs (NSAIDs). We assessed their effects on an experimental ocular inflammation in New Zealand rabbits. The formulations of CAPE-aspirin and CAPE-indomethacin hybrids were topical instilled in the rabbit&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s eye. Afterwards, the anti-inflammatory activity was evaluated by grading the clinical signs and by assessing the inflammatory cell count, protein, PGE2 and TNFα levels in the aqueous humor. Furthermore, ocular tolerability of hybrids formulations was evaluated in a separate set of animals by using a modified Draize test. The ocular inflammation in the control group was significantly higher than in both the hybrid-treated groups, as indicated by clinical grading and biomarkers assessment. However, only the CAPE-aspirin hybrid reduced, in a significant dose-dependent manner, the ocular inflammation elicited by paracentesis. CAPE-indomethacin hybrid was able to significantly attenuate the clinical grading and the PGE2 aqueous levels only at the highest dose (0.1%). CAPE-aspirin significantly reduced PGE2 and TNFα levels in the aqueous humor as well as proteins and PMNs. Finally, all formulations showed no ocular irritation compared with vehicle-treated group. In conclusion, CAPE-aspirin shows full anti-inflammatory efficacy in experimental model of ocular inflammation demonstrating an optimal pharmacological and safety profile. Taken together these data indicate that CAPE-aspirin hybrid represents a valid and safe new chemical entity potentially useful for the treatment of ocular inflammation.
The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was en... more The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was enhanced by its encapsulation in cationic solid lipid nanoparticles (cSLN), as well as at determining the tolerability of these formulations on the ocular surface. MEL was loaded in cSLN that had already been shown to be suitable for ophthalmic use. The formulations were prepared using Softisan(®) 100 as the main lipid matrix, with the presence of either stearic (SA) or palmitic acid (PA) as lipid modifiers. A fixed positive charge was provided by the addition of a cationic lipid (didecyldimethylammonium bromide). The ocular hypotensive effect was evaluated by measuring the intraocular pressure (IOP) during 24h in albino rabbits. MEL elicited a significant (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.01) IOP reduction in rabbit eye. All the formulations tested in vivo demonstrated a good tolerability. The nanocarrier containing SA was the most effective in terms of IOP reduction (maximum IOP reduction: -7mmHg), and its effect lasted approximately 24h. The experimental data indicate that the new formulations based on cSLN loaded with MEL represent a potent anti-glaucoma treatment with a safe profile, warranting further clinical evaluation of the proposed nanotechnological strategy.
Nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H2S) modulate vascular tone. In vi... more Nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H2S) modulate vascular tone. In view of their therapeutic potential for ocular diseases, we examined the effect of exogenous CO and H2S on tone of isolated rabbit ophthalmic artery and their interaction with endogenous and exogenous NO. Ophthalmic artery segments mounted on a wire myograph were challenged with cumulative concentrations of phenylephrine (PE) in the presence or absence of NG-nitro-L-arginine (LNNA) to inhibit production of NO, the CO-releasing molecules CORMs or the H2S-donor GYY4137. The maximal vasoconstriction elicited by PE reached 20-30% of that induced by KCl but was dramatically increased by incubation with LNNA. GYY4137 significantly raised PE-mediated vasoconstriction, but it did not change the response to PE in the presence of LNNA or the relaxation to sodium nitroprusside (SNP). CORMs concentration-dependently inhibited PE-induced constriction, an effect that was synergistic with endogenous NO (reduced by LNNA), but insensitive to blockade of guanylyl cyclase by 1H-[1,2,4]oxadiazolo[4,3,-α]quinoxalin-1-one (ODQ). In vascular tissues cyclic GMP (cGMP) levels seemed reduced by GYY4137 (not significantly), but were not changed by CORM. These data indicate that CO is able per se to relax isolated ophthalmic artery and to synergize with NO, while H2S counteracts the effect of endogenous NO. CO does not stimulate cGMP production in our system, while H2S may reduce cGMP production stimulated by endogenous NO. These findings provide new insights into the complexities of gas interactions in the control of ophthalmic vascular tone, highlighting potential pharmacological targets for ocular diseases.
Parkinson protein 2, E3 ubiquitin protein ligase (PARK2) gene mutations are the most frequent cau... more Parkinson protein 2, E3 ubiquitin protein ligase (PARK2) gene mutations are the most frequent causes of autosomal recessive early onset Parkinson&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s disease and juvenile Parkinson disease. Parkin deficiency has also been linked to other human pathologies, for example, sporadic Parkinson disease, Alzheimer disease, autism, and cancer. PARK2 primary transcript undergoes an extensive alternative splicing, which enhances transcriptomic diversification. To date several PARK2 splice variants have been identified; however, the expression and distribution of parkin isoforms have not been deeply investigated yet. Here, the currently known PARK2 gene transcripts and relative predicted encoded proteins in human, rat, and mouse are reviewed. By analyzing the literature, we highlight the existing data showing the presence of multiple parkin isoforms in the brain. Their expression emerges from conflicting results regarding the electrophoretic mobility of the protein, but it is also assumed from discrepant observations on the cellular and tissue distribution of parkin. Although the characterization of each predicted isoforms is complex, since they often diverge only for few amino acids, analysis of their expression patterns in the brain might account for the different pathogenetic effects linked to PARK2 gene mutations.
Hyperglycemia has been identified as a risk factor responsible for micro- and macrovascular compl... more Hyperglycemia has been identified as a risk factor responsible for micro- and macrovascular complications in diabetes. NAP (Davunetide) is a peptide whose neuroprotective actions are widely demonstrated, although its biological role on endothelial dysfunctions induced by hyperglycemia remains uninvestigated. In the present study we hypothesized that NAP could play a protective role on hyperglycemia-induced endothelial cell proliferation. To this end we investigated the effects of NAP on an in vitro model of murine microvascular endothelial cells grown in high glucose for 7 days. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and cyclin D1 protein expression analysis revealed that NAP treatment significantly reduces viability and proliferation of the cells. Hyperglycemia induced the activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase and/or phosphatidylinositol-3 kinase/Akt pathways in a time-dependent manner. NAP treatment reduced the phosphorylation levels of ERK and AKT in cells grown in high glucose. These evidences suggest that NAP might be effective in the regulation of endothelial dysfunction induced by hyperglycemia.
Addition of one or more surfactant agents is often necessary for the production of nanostructured... more Addition of one or more surfactant agents is often necessary for the production of nanostructured lipid and polymeric systems. The removal of residual surfactants is a required step for technological and toxicological reasons, especially for peculiar applications, such as the ophthalmic field. This study was planned to assess the technological properties of some surfactants, commonly used for the production of lipid nanoparticles, as well as their ocular safety profile. Stable and small-size solid lipid nanoparticles were obtained using Dynasan(®) 114 as the lipid matrix and all the tested surfactants. However, from a toxicological point of view, the nanocarriers produced using Kolliphor(®) P188 were the most valuable, showing no irritant effect on the ocular surface up to the highest tested surfactant concentration (0.4%, w/v). The SLN produced using Cremophor(®) A25 and Lipoid(®) S100 were tolerated up to a surfactant concentration of 0.2% by weight, while for Tween(®) 80 and Kolliphor(®) HS 15 a maximum concentration of 0.05% can be considered totally not-irritant.
Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a... more Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a neurovascular complication of diabetes mellitus and it is the leading cause of vision loss among working adults worldwide. In this study, we evaluate the role of homocysteine in diabetic retinopathy analyzing the plasma levels of homocysteine in 63 diabetic type 2 patients with nonproliferative retinopathy (NPDR), 62 patients with proliferative diabetic retinopathy (PDR), 50 healthy subjects used as control group, and 75 randomly selected patients.
Diabetic retinopathy, a major cause of vision loss, is currently treated with anti-VEGF agents. H... more Diabetic retinopathy, a major cause of vision loss, is currently treated with anti-VEGF agents. Here we tested two hypotheses: (i) high glucose damages retinal pericytes, the cell layer surrounding endothelial cells, via VEGF induction, which may be counteracted by anti-VEGFs and (ii) activation of PLA2/COX-2 pathway by high glucose might be upstream and/or downstream of VEGF in perycites, as previously observed in endothelial cells. Human retinal pericytes were treated with high glucose (25mM) for 48h and/or anti-VEGFs (40μg/ml aflibercept, 25μg/ml bevacizumab, 10μg/ml ranibizumab). All anti-VEGFs significantly prevented high glucose-induced cell damage (assessed by LDH release) and improved cell viability (assessed by MTT and Evans blue). High glucose-induced VEGF-A expression, as detected both at mRNA (qPCR) and protein (ELISA) level, while receptor (VEGFR1 and VEGFR2) expression, detected in control condition, was unaffected by treatments. High glucose induced also activation of PLA2/COX-2 pathway, as revealed by increased phosphorylation of cPLA2, COX-2 expression and PGE2 release. Treatment with cPLA2 (50μM AACOCF3) and COX-2 (5μM NS-392) inhibitors prevented both cell damage and VEGF-A induced by high glucose. Finally, challenge with exogenous VEGF-A (10ng/ml) induced VEGF-A expression, while anti-VEGFs reduced VEGF-A expression induced by either high glucose or exogenous VEGF-A. These data indicate that high glucose directly damages pericytes through activation of PLA2/COX-2/VEGF-A pathway. Furthermore, a kind of feed-forward loop between cPLA2/COX-2/PG axis and VEGF appears to operate in this system. Thus, anti-VEGFs afford protection of pericytes from high glucose by inhibiting this loop.
In recent years, efforts have been directed to develop "disease-modifying drugs" for Al... more In recent years, efforts have been directed to develop "disease-modifying drugs" for Alzheimer's disease (AD), i.e. drugs able to counteract the progression of AD. Because the earlier the treatment starts, the greater is the chance of success, it is crucial to develop reliable biomarkers for early detection of AD-related brain dysfunction, possibly before clinical onset. Disease-modifying drugs developed so far include drugs to reduce β amyloid (Aβ) production, drugs to prevent Aβ aggregation, drugs to promote Aβ clearance, drugs targeting tau phosphorylation and assembly, and other approaches. Active and passive immunotherapy is the main strategy aimed at increasing Aβ clearance. Unfortunately several candidate disease-modifying drugs have failed in phase III clinical trials conducted in mild to moderate AD. More recently, in phase III studies, bapineuzumab has been discontinued because it did not prove clinically effective (despite its significant effect on biomarker...
The International journal of social psychiatry, Jan 12, 2015
The aim was to measure the lifetime prevalence of panic disorder (PD) in an Italian community sam... more The aim was to measure the lifetime prevalence of panic disorder (PD) in an Italian community sample, and to estimate the burden attributable to PD in compromising the quality of life (QoL) of people diagnosed with it. Community survey was conducted on a sample of 4,999 randomly selected adult subjects. Instruments used were semi-structured clinical interview Advanced Neuropsychiatric Tools and Assessment Schedule (ANTAS), administered by clinicians and allowing diagnosis according to Diagnostic and Statistical Manual of Mental Disorder (4th ed.; DSM-IV); Short Form Health Survey (SF-12). The lifetime prevalence of PD was 3.6% (4.4% in females, 2.5% in males; p = .002). People with PD had a lower SF-12 score than the standardized community sample (35.5 ± 6.5 vs. 38.4 ± 5.9; p < .0001) with a mean difference (attributable burden) of 2.9 ± 0.7, that is, lower than PD with agoraphobia (AP; 4.2 ± 2.4). Wilson Disease (WD), Multiple Sclerosis, Major Depressive Disorder and Eating Diso...
PACAP and its cognate peptide VIP participate in various biological functions, including myelin m... more PACAP and its cognate peptide VIP participate in various biological functions, including myelin maturation and synthesis. However, defining whether these peptides affect peripheral expression of myelin proteins still remains unanswered. To address this issue, we assessed whether PACAP or VIP contribute to regulate the expression of three myelin proteins (MAG, MBP and MPZ, respectively) using the rat schwannoma cell line (RT4-P6D2T), a well-established model to study myelin gene expression. In addition, we endeavored to partly unravel the underlying molecular mechanisms involved. Expression of myelin-specific proteins was assessed in cells grown either in normal serum (10% FBS) or serum starved and treated with or without 100 nM PACAP or VIP. Furthermore, through pharmacological approach using the PACAP/VIP receptor antagonist (PACAP6-38) or specific pathway (MAPK or PI3K) inhibitors we defined the relative contribution of receptors and/or signaling pathways on the expression of myel...
The changing of omega-6/omega-3 polyunsaturated fatty acids (PUFA) in the food supply of Western ... more The changing of omega-6/omega-3 polyunsaturated fatty acids (PUFA) in the food supply of Western societies occurred over the last 150 years is thought to promote the pathogenesis of many inflammatory-related diseases, including depressive disorders. Several epidemiological studies reported a significant inverse correlation between intake of oily fish and depression or bipolar disorders. Studies conducted specifically on the association between omega-3 intake and depression reported contrasting results, suggesting that the preventive role of omega-3 PUFA may depend also on other factors, such as overall diet quality and the social environment. Accordingly, tertiary prevention with omega-3 PUFA supplement in depressed patients has reached greater effectiveness during the last recent years, although definitive statements on their use in depression therapy cannot be yet freely asserted. Among the biological properties of omega-3 PUFA, their anti-inflammatory effects and their important ...
Despite omega-3 polyunsaturated fatty acids (PUFA) supplementation in depressed patients have bee... more Despite omega-3 polyunsaturated fatty acids (PUFA) supplementation in depressed patients have been suggested to improve depressive symptomatology, previous findings are not univocal. To conduct an updated meta-analysis of randomized controlled trials (RCTs) of omega-3 PUFA treatment of depressive disorders, taking into account the clinical differences among patients included in the studies. A search on MEDLINE, EMBASE, PsycInfo, and the Cochrane Database of RCTs using omega-3 PUFA on patients with depressive symptoms published up to August 2013 was performed. Standardized mean difference in clinical measure of depression severity was primary outcome. Type of omega-3 used (particularly eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) and omega-3 as mono- or adjuvant therapy was also examined. Meta-regression analyses assessed the effects of study size, baseline depression severity, trial duration, dose of omega-3, and age of patients. Meta-analysis of 11 and 8 trials condu...
In this study, we report the design and synthesis of novel hybrids of caffeic acid phenetyl ester... more In this study, we report the design and synthesis of novel hybrids of caffeic acid phenetyl ester (CAPE) and non-steroidal anti-inflammatory drugs (NSAIDs). We assessed their effects on an experimental ocular inflammation in New Zealand rabbits. The formulations of CAPE-aspirin and CAPE-indomethacin hybrids were topical instilled in the rabbit&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s eye. Afterwards, the anti-inflammatory activity was evaluated by grading the clinical signs and by assessing the inflammatory cell count, protein, PGE2 and TNFα levels in the aqueous humor. Furthermore, ocular tolerability of hybrids formulations was evaluated in a separate set of animals by using a modified Draize test. The ocular inflammation in the control group was significantly higher than in both the hybrid-treated groups, as indicated by clinical grading and biomarkers assessment. However, only the CAPE-aspirin hybrid reduced, in a significant dose-dependent manner, the ocular inflammation elicited by paracentesis. CAPE-indomethacin hybrid was able to significantly attenuate the clinical grading and the PGE2 aqueous levels only at the highest dose (0.1%). CAPE-aspirin significantly reduced PGE2 and TNFα levels in the aqueous humor as well as proteins and PMNs. Finally, all formulations showed no ocular irritation compared with vehicle-treated group. In conclusion, CAPE-aspirin shows full anti-inflammatory efficacy in experimental model of ocular inflammation demonstrating an optimal pharmacological and safety profile. Taken together these data indicate that CAPE-aspirin hybrid represents a valid and safe new chemical entity potentially useful for the treatment of ocular inflammation.
The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was en... more The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was enhanced by its encapsulation in cationic solid lipid nanoparticles (cSLN), as well as at determining the tolerability of these formulations on the ocular surface. MEL was loaded in cSLN that had already been shown to be suitable for ophthalmic use. The formulations were prepared using Softisan(®) 100 as the main lipid matrix, with the presence of either stearic (SA) or palmitic acid (PA) as lipid modifiers. A fixed positive charge was provided by the addition of a cationic lipid (didecyldimethylammonium bromide). The ocular hypotensive effect was evaluated by measuring the intraocular pressure (IOP) during 24h in albino rabbits. MEL elicited a significant (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.01) IOP reduction in rabbit eye. All the formulations tested in vivo demonstrated a good tolerability. The nanocarrier containing SA was the most effective in terms of IOP reduction (maximum IOP reduction: -7mmHg), and its effect lasted approximately 24h. The experimental data indicate that the new formulations based on cSLN loaded with MEL represent a potent anti-glaucoma treatment with a safe profile, warranting further clinical evaluation of the proposed nanotechnological strategy.
Nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H2S) modulate vascular tone. In vi... more Nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H2S) modulate vascular tone. In view of their therapeutic potential for ocular diseases, we examined the effect of exogenous CO and H2S on tone of isolated rabbit ophthalmic artery and their interaction with endogenous and exogenous NO. Ophthalmic artery segments mounted on a wire myograph were challenged with cumulative concentrations of phenylephrine (PE) in the presence or absence of NG-nitro-L-arginine (LNNA) to inhibit production of NO, the CO-releasing molecules CORMs or the H2S-donor GYY4137. The maximal vasoconstriction elicited by PE reached 20-30% of that induced by KCl but was dramatically increased by incubation with LNNA. GYY4137 significantly raised PE-mediated vasoconstriction, but it did not change the response to PE in the presence of LNNA or the relaxation to sodium nitroprusside (SNP). CORMs concentration-dependently inhibited PE-induced constriction, an effect that was synergistic with endogenous NO (reduced by LNNA), but insensitive to blockade of guanylyl cyclase by 1H-[1,2,4]oxadiazolo[4,3,-α]quinoxalin-1-one (ODQ). In vascular tissues cyclic GMP (cGMP) levels seemed reduced by GYY4137 (not significantly), but were not changed by CORM. These data indicate that CO is able per se to relax isolated ophthalmic artery and to synergize with NO, while H2S counteracts the effect of endogenous NO. CO does not stimulate cGMP production in our system, while H2S may reduce cGMP production stimulated by endogenous NO. These findings provide new insights into the complexities of gas interactions in the control of ophthalmic vascular tone, highlighting potential pharmacological targets for ocular diseases.
Parkinson protein 2, E3 ubiquitin protein ligase (PARK2) gene mutations are the most frequent cau... more Parkinson protein 2, E3 ubiquitin protein ligase (PARK2) gene mutations are the most frequent causes of autosomal recessive early onset Parkinson&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s disease and juvenile Parkinson disease. Parkin deficiency has also been linked to other human pathologies, for example, sporadic Parkinson disease, Alzheimer disease, autism, and cancer. PARK2 primary transcript undergoes an extensive alternative splicing, which enhances transcriptomic diversification. To date several PARK2 splice variants have been identified; however, the expression and distribution of parkin isoforms have not been deeply investigated yet. Here, the currently known PARK2 gene transcripts and relative predicted encoded proteins in human, rat, and mouse are reviewed. By analyzing the literature, we highlight the existing data showing the presence of multiple parkin isoforms in the brain. Their expression emerges from conflicting results regarding the electrophoretic mobility of the protein, but it is also assumed from discrepant observations on the cellular and tissue distribution of parkin. Although the characterization of each predicted isoforms is complex, since they often diverge only for few amino acids, analysis of their expression patterns in the brain might account for the different pathogenetic effects linked to PARK2 gene mutations.
Hyperglycemia has been identified as a risk factor responsible for micro- and macrovascular compl... more Hyperglycemia has been identified as a risk factor responsible for micro- and macrovascular complications in diabetes. NAP (Davunetide) is a peptide whose neuroprotective actions are widely demonstrated, although its biological role on endothelial dysfunctions induced by hyperglycemia remains uninvestigated. In the present study we hypothesized that NAP could play a protective role on hyperglycemia-induced endothelial cell proliferation. To this end we investigated the effects of NAP on an in vitro model of murine microvascular endothelial cells grown in high glucose for 7 days. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and cyclin D1 protein expression analysis revealed that NAP treatment significantly reduces viability and proliferation of the cells. Hyperglycemia induced the activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase and/or phosphatidylinositol-3 kinase/Akt pathways in a time-dependent manner. NAP treatment reduced the phosphorylation levels of ERK and AKT in cells grown in high glucose. These evidences suggest that NAP might be effective in the regulation of endothelial dysfunction induced by hyperglycemia.
Addition of one or more surfactant agents is often necessary for the production of nanostructured... more Addition of one or more surfactant agents is often necessary for the production of nanostructured lipid and polymeric systems. The removal of residual surfactants is a required step for technological and toxicological reasons, especially for peculiar applications, such as the ophthalmic field. This study was planned to assess the technological properties of some surfactants, commonly used for the production of lipid nanoparticles, as well as their ocular safety profile. Stable and small-size solid lipid nanoparticles were obtained using Dynasan(®) 114 as the lipid matrix and all the tested surfactants. However, from a toxicological point of view, the nanocarriers produced using Kolliphor(®) P188 were the most valuable, showing no irritant effect on the ocular surface up to the highest tested surfactant concentration (0.4%, w/v). The SLN produced using Cremophor(®) A25 and Lipoid(®) S100 were tolerated up to a surfactant concentration of 0.2% by weight, while for Tween(®) 80 and Kolliphor(®) HS 15 a maximum concentration of 0.05% can be considered totally not-irritant.
Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a... more Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a neurovascular complication of diabetes mellitus and it is the leading cause of vision loss among working adults worldwide. In this study, we evaluate the role of homocysteine in diabetic retinopathy analyzing the plasma levels of homocysteine in 63 diabetic type 2 patients with nonproliferative retinopathy (NPDR), 62 patients with proliferative diabetic retinopathy (PDR), 50 healthy subjects used as control group, and 75 randomly selected patients.
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Papers by Filippo Drago