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1.
Neurosci Lett ; 736: 135272, 2020 09 25.
Article in English | MEDLINE | ID: mdl-32712350

ABSTRACT

Heat shock protein 70 family was demonstrated to play a critical role in protein homeostasis, a process profoundly impaired in neurodegenerative disorders. Neurodegenerative diseases are characterized by the accumulation of different kind of proteins and the formation of insoluble aggregates which are toxic for neurons. To explore the role of heat shock protein family 70 (in particular HSPA8 and HSPA1A) in the accumulation of proteins implied in neurodegeneration pathogenesis, in this study we verified in human SH-SY5Y neuroblastoma cells how HSPA8 or HSPA1A knock-down can affect protein levels of tau, superoxide dismutase 1 and α-synuclein. We found HSPA8 and HSPA1A reduction caused an increase of tau, superoxide dismutase 1 and α-synuclein protein levels. We also noticed HSPA8 knock-down increased α-synuclein oligomeric forms and mRNA expression. Our results suggest HSPA8 can play an important role in the homeostasis of tau, superoxide dismutase 1 and α-synuclein and in the balance between α-synuclein oligomeric and monomeric forms.


Subject(s)
HSC70 Heat-Shock Proteins/metabolism , Neurons/metabolism , Superoxide Dismutase/metabolism , alpha-Synuclein/metabolism , tau Proteins/metabolism , Cell Line, Tumor , Gene Knockdown Techniques , HSC70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/metabolism , Humans
2.
Article in English | MEDLINE | ID: mdl-31663379

ABSTRACT

Aim: The demonstration that chaperone-mediated autophagy (CMA) contributes to the degradation of TDP-43, the main constituent of cytoplasmic inclusions typically found in motor neurons of patients with sporadic amyotrophic lateral sclerosis (sALS), has pointed out a possible involvement of CMA in aggregate formation. To explore this possibility, in this study, we verified the presence of a possible systemic CMA alteration in sALS patients and its effect on TDP-43 expression. Materials and methods: Gene and protein expression of the cytosolic chaperone HSC70 and the lysosome receptor LAMP2A, the two pivotal mediators of CMA, was assessed in peripheral blood mononuclear cells (PBMCs) derived from 30 sALS patients and 30 healthy controls. The expression of TDP-43 and co-chaperones BAG1 and BAG3 was also analyzed. Results: We found reduced HSC70 expression in patient cells, with no change in LAMP2A, and increased insoluble TDP-43 protein levels, with an aberrant intracellular localization. We also observed an unbalanced expression of co-chaperones BAG1 and BAG3. HSC70 down-regulation was confirmed in immortalized lymphoblastoid cell lines derived from sporadic and TARDBP mutant ALS patients. Lastly, we demonstrated that HSC70 silencing directly increases TDP-43 protein levels in human neuroblastoma cells. Discussion: Our results do not support the existence of a systemic CMA alteration in sALS patients but indicate a direct involvement of HSC70 alterations in ALS pathogenesis.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , DNA-Binding Proteins/metabolism , HSC70 Heat-Shock Proteins/metabolism , Leukocytes, Mononuclear/metabolism , Adaptor Proteins, Signal Transducing/genetics , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/metabolism , Autophagy/physiology , DNA-Binding Proteins/genetics , Female , HSC70 Heat-Shock Proteins/genetics , Humans , Inclusion Bodies/metabolism , Male , Motor Neurons/metabolism
3.
Food Chem ; 252: 171-180, 2018 Jun 30.
Article in English | MEDLINE | ID: mdl-29478529

ABSTRACT

To identify food and beverages that provide the regular intake of natural compounds capable of interfering with toxic amyloidogenic aggregates, we developed an experimental protocol that combines NMR spectroscopy and atomic force microscopy, in vitro biochemical and cell assays to detect anti-Aß molecules in natural edible matrices. We applied this approach to investigate the potential anti-amyloidogenic properties of coffee and its molecular constituents. Our data showed that green and roasted coffee extracts and their main components, 5-O-caffeoylquinic acid and melanoidins, can hinder Aß on-pathway aggregation and toxicity in a human neuroblastoma SH-SY5Y cell line. Coffee extracts and melanoidins also counteract hydrogen peroxide- and rotenone-induced cytotoxicity and modulate some autophagic pathways in the same cell line.


Subject(s)
Amyloid beta-Peptides/chemistry , Coffee/chemistry , Food Handling , Plant Extracts/chemistry , Plant Extracts/pharmacology , Protein Multimerization/drug effects , Cell Line, Tumor , Color , Humans , Magnetic Resonance Spectroscopy
4.
Neurotoxicology ; 54: 161-169, 2016 05.
Article in English | MEDLINE | ID: mdl-27133439

ABSTRACT

HSPA8/hsc70 (70-kDa heat shock cognate) chaperone protein exerts multiple protective roles. Beside its ability to confer to the cells a generic resistance against several metabolic stresses, it is also involved in at least two critical processes whose activity is essential in preventing Parkinson's disease (PD) pathology. Actually, hsc70 protein acts as the main carrier of chaperone-mediated autophagy (CMA), a selective catabolic pathway for alpha-synuclein, the main pathogenic protein that accumulates in degenerating dopaminergic neurons in PD. Furthermore, hsc70 efficiently fragments alpha-synuclein fibrils in vitro and promotes depolymerization into non-toxic alpha-synuclein monomers. Considering that the mitochondrial complex I inhibitor rotenone, used to generate PD animal models, induces alpha-synuclein aggregation, this study was designed in order to verify whether rotenone exposure leads to hsc70 alteration possibly contributing to alpha-synuclein aggregation. To this aim, human SH-SY5Y neuroblastoma cells were treated with rotenone and hsc70 mRNA and protein expression were assessed; the effect of rotenone on hsc70 was compared with that exerted by hydrogen peroxide, a generic oxidative stress donor with no inhibitory activity on mitochondrial complex I. Furthermore, the effect of rotenone on hsc70 was verified in primary mouse cortical neurons. The possible contribution of macroautophagy to rotenone-induced hsc70 modulation was explored and the influence of hsc70 gene silencing on neurotoxicity was assessed. We demonstrated that rotenone, but not hydrogen peroxide, induced a significant reduction of hsc70 mRNA and protein expression. We also observed that the toxic effect of rotenone on alpha-synuclein levels was amplified when macroautophagy was inhibited, although rotenone-induced hsc70 reduction was independent from macroautophagy. Finally, we demonstrated that hsc70 gene silencing up-regulated alpha-synuclein mRNA and protein levels without affecting cell viability and without altering rotenone- and hydrogen peroxide-induced cytotoxicity. These findings demonstrate the existence of a novel mechanism of rotenone toxicity mediated by hsc70 and indicate that dysfunction of both CMA and macroautophagy can synergistically exacerbate alpha-synuclein toxicity, suggesting that hsc70 up-regulation may represent a valuable therapeutic strategy for PD.


Subject(s)
Gene Expression Regulation/drug effects , HSC70 Heat-Shock Proteins/metabolism , Insecticides/pharmacology , Neurons/drug effects , Rotenone/pharmacology , Animals , Animals, Newborn , Cell Line, Tumor , Cells, Cultured , Cerebral Cortex/cytology , HSC70 Heat-Shock Proteins/genetics , Humans , Hydrogen Peroxide/pharmacology , Mice , Mice, Inbred C57BL , Neuroblastoma/pathology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Reactive Oxygen Species/metabolism , Time Factors , Transfection , alpha-Synuclein/metabolism
5.
Brain Res ; 1546: 46-52, 2014 Feb 10.
Article in English | MEDLINE | ID: mdl-24361989

ABSTRACT

Chaperone-mediated autophagy (CMA) impairment is recognized to play a pathogenetic role in Parkinson's disease (PD). A reduced expression of lysosomal-associated membrane protein (lamp) 2A and heat shock cognate (hsc) 70 protein, the two key regulators of CMA, has been reported in brains of PD patients. To verify the existence of a possible systemic CMA dysfunction in PD, in this study the expression of hsc70 and lamp2A was assessed in peripheral blood mononuclear cells (PBMC) of patients with sporadic PD and compared to healthy subjects. The expression of myocyte enhancer factor 2D (MEF2D), a transcriptional factor implicated in neuronal survival and specific substrate of CMA, was also evaluated. Protein and gene expression was assessed by Western blot and real-time PCR, respectively, in PBMC obtained from 53 sporadic PD patients and 53 healthy subjects. A significant reduction of hsc70 levels was observed in PBMC of PD patients, both under basal conditions and after autophagy induction obtained with serum deprivation. No difference emerged in lamp2A and MEF2D expression between patients and controls. No influence of the clinical characteristics of patients emerged on hsc70, lamp2A and MEF2D expression. These results, despite being not suggestive of the existence of a CMA impairment in PBMC of PD patients, identify a systemic hsc70 reduction in PD patients. Further studies on specific mechanisms and biological significance of such alteration are needed to corroborate this finding that could lead to the identification of a new trait biomarker for PD.


Subject(s)
Autophagy/physiology , HSC70 Heat-Shock Proteins/metabolism , Leukocytes, Mononuclear/metabolism , Parkinson Disease/metabolism , Aged , Cell Survival , Female , HSC70 Heat-Shock Proteins/blood , Humans , Lysosomal-Associated Membrane Protein 2/blood , Lysosomal-Associated Membrane Protein 2/metabolism , MEF2 Transcription Factors/blood , MEF2 Transcription Factors/metabolism , Male , Middle Aged , Parkinson Disease/blood
6.
Biomed Res Int ; 2013: 846725, 2013.
Article in English | MEDLINE | ID: mdl-23984410

ABSTRACT

Dysfunctions of chaperone-mediated autophagy (CMA), the main catabolic pathway for alpha-synuclein, have been linked to the pathogenesis of Parkinson's disease (PD). Since till now there is limited information on how PD-related toxins may affect CMA, in this study we explored the effect of mitochondrial complex I inhibitor rotenone on CMA substrates, alpha-synuclein and MEF2D, and effectors, lamp2A and hsc70, in a human dopaminergic neuroblastoma SH-SY5Y cell line. Rotenone induced an upregulation of alpha-synuclein and MEF2D protein levels through the stimulation of their de novo synthesis rather than through a reduction of their CMA-mediated degradation. Moreover, increased MEF2D transcription resulted in higher nuclear protein levels that exert a protective role against mitochondrial dysfunction and oxidative stress. These results were compared with those obtained after lysosome inhibition with ammonium chloride. As expected, this toxin induced the cytosolic accumulation of both alpha-synuclein and MEF2D proteins, as the result of the inhibition of their lysosome-mediated degradation, while, differently from rotenone, ammonium chloride decreased MEF2D nuclear levels through the downregulation of its transcription, thus reducing its protective function. These results highlight that rotenone affects alpha-synuclein and MEF2D protein levels through a mechanism independent from lysosomal degradation inhibition.


Subject(s)
Lysosomes/metabolism , MEF2 Transcription Factors/genetics , Proteolysis/drug effects , Rotenone/toxicity , Up-Regulation/drug effects , alpha-Synuclein/genetics , Ammonium Chloride/pharmacology , Apoptosis Regulatory Proteins/metabolism , Beclin-1 , Cell Death/drug effects , Cell Line , Cell Nucleus/drug effects , Cell Nucleus/metabolism , HSC70 Heat-Shock Proteins/genetics , HSC70 Heat-Shock Proteins/metabolism , Humans , Lysosomal-Associated Membrane Protein 2/genetics , Lysosomal-Associated Membrane Protein 2/metabolism , Lysosomes/drug effects , MEF2 Transcription Factors/metabolism , Membrane Proteins/metabolism , Microtubule-Associated Proteins/metabolism , Phagosomes/drug effects , Phagosomes/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Transcription, Genetic/drug effects , alpha-Synuclein/metabolism
7.
Neurobiol Aging ; 34(6): 1712.e9-13, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23369548

ABSTRACT

Generation of reactive oxygen species during dopamine (DA) oxidation could be one of the factors leading to the selective loss of nigral dopaminergic neurons in Parkinson's disease (PD). Vesicular monoamine transporter type 2 (VMAT2) proteins in nerve terminals uptake dopamine into synaptic vesicles, preventing its cytoplasmic accumulation and toxic damage to nigral neurons. Polymorphisms in VMAT2 gene and in its regulatory regions might therefore serve as genetic risk factors for PD. In the present study, we have analyzed 8 single-nucleotide polymorphisms (SNPs) located within/around the VMAT2 gene for association with PD in an Italian cohort composed of 704 PD patients and 678 healthy controls. Among the 8 SNPs studied, only the 2 located within the promoter region (rs363371 and rs363324) were significantly associated with PD. In the dominant model, odds ratios were 0.72 (95% confidence interval [CI]: 0.6-0.9, p < 0.005) for rs363371 and 0.76 (95% CI: 0.6-0.9, p = 0.01) for rs363324; in the additive model, odds ratios were 0.78 (95% CI: 0.65-0.94, p = 0.008) for rs363371 and 0.85 (95% CI: 0.7-20.92, p = 0.04) for rs363324. There were no significant relationships between the remaining SNPs (rs363333, rs363399, rs363387, rs363343, rs4752045, and rs363236) and the risk of sporadic PD in any genetic model. This study adds to the previous evidence suggesting that variability in VMAT2 promoter region may confer a reduced risk of developing PD, presumably via mechanisms of gene overexpression.


Subject(s)
Parkinson Disease/diagnosis , Parkinson Disease/genetics , Polymorphism, Single Nucleotide/genetics , Vesicular Monoamine Transport Proteins/genetics , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Parkinson Disease/epidemiology
8.
Retrovirology ; 9: 81, 2012 Oct 03.
Article in English | MEDLINE | ID: mdl-23031662

ABSTRACT

BACKGROUND: The effect of drug resistance transmission on disease progression in the newly infected patient is not well understood. Major drug resistance mutations severely impair viral fitness in a drug free environment, and therefore are expected to revert quickly. Compensatory mutations, often already polymorphic in wild-type viruses, do not tend to revert after transmission. While compensatory mutations increase fitness during treatment, their presence may also modulate viral fitness and virulence in absence of therapy and major resistance mutations. We previously designed a modeling technique that quantifies genotypic footprints of in vivo treatment selective pressure, including both drug resistance mutations and polymorphic compensatory mutations, through the quantitative description of a fitness landscape from virus genetic sequences. RESULTS: Genotypic correlates of viral load and CD4 cell count were evaluated in subtype B sequences from recently diagnosed treatment-naive patients enrolled in the SPREAD programme. The association of surveillance drug resistance mutations, reported compensatory mutations and fitness estimated from drug selective pressure fitness landscapes with baseline viral load and CD4 cell count was evaluated using regression techniques. Protease genotypic variability estimated to increase fitness during treatment was associated with higher viral load and lower CD4 cell counts also in treatment-naive patients, which could primarily be attributed to well-known compensatory mutations at highly polymorphic positions. By contrast, treatment-related mutations in reverse transcriptase could not explain viral load or CD4 cell count variability. CONCLUSIONS: These results suggest that polymorphic compensatory mutations in protease, reported to be selected during treatment, may improve the replicative capacity of HIV-1 even in absence of drug selective pressure or major resistance mutations. The presence of this polymorphic variation may either reflect a history of drug selective pressure, i.e. transmission from a treated patient, or merely be a result of diversity in wild-type virus. Our findings suggest that transmitted drug resistance has the potential to contribute to faster disease progression in the newly infected host and to shape the HIV-1 epidemic at a population level.


Subject(s)
Anti-HIV Agents/therapeutic use , CD4 Lymphocyte Count , HIV Infections/drug therapy , HIV-1/enzymology , Peptide Hydrolases/genetics , Polymorphism, Genetic , Viral Load , Viral Proteins/genetics , Adult , Drug Resistance, Viral , Female , HIV Infections/immunology , HIV Infections/virology , HIV-1/drug effects , HIV-1/genetics , HIV-1/physiology , Humans , Male , Peptide Hydrolases/metabolism , Prospective Studies , Viral Proteins/metabolism
9.
Prog Neuropsychopharmacol Biol Psychiatry ; 39(1): 47-51, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-22584634

ABSTRACT

Valproate (VPA) is an anti-epileptic and mood-stabilizing drug with a broad range of action and which mechanism of action still remains in part elusive. Recently the discovery that VPA modifies the epigenome increasing the transcriptional rate of target genes raises the issue of understanding the exact role of this mechanism. In this work we tested the possibility that VPA could modify the epigenome of lymphomonocytes (PBMC) obtained from epileptic patients chronically treated in monotherapy with VPA and phenobarbital. Acetyl-histone H3 expression was assessed by western blotting and global DNA methylation by incorporation of [³H]dCTP. A significant increase in histone acetylation and a correlated decrease of global DNA methylation were shown at VPA therapeutically relevant plasma concentrations. This effect was drug-related, since it was not demonstrated in PBMC obtained from phenobarbital-treated patients. Moreover, a VPA dose-response curve was performed on PBMC obtained from healthy controls, demonstrating an increase of acetyl-histone H3 content. We suggest that the epigenetic properties of VPA expressed on PBMC at these concentrations might be operative in different tissues, with possible implications for the field of neuropsychiatric disorders.


Subject(s)
Anticonvulsants/pharmacology , Epigenesis, Genetic/drug effects , Epigenomics/methods , Epilepsy/metabolism , Leukocytes, Mononuclear/metabolism , Valproic Acid/pharmacology , Acetylation/drug effects , Adult , Case-Control Studies , DNA Methylation/drug effects , Dose-Response Relationship, Drug , Epilepsy/blood , Female , Histones/metabolism , Humans , Male , Middle Aged , Phenobarbital/pharmacology
10.
Parkinsonism Relat Disord ; 17(9): 701-4, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21767974

ABSTRACT

Alpha-synuclein accumulation in intracellular inclusions, oxidative stress and microglia-mediated inflammation in the substantia nigra are crucial events in the pathogenesis of Parkinson's disease (PD). Poly (ADP-ribose) polymerase-1 (PARP1), a DNA-binding enzyme and transcriptional regulator, plays an important role in modulating the cellular response to oxidative stress, inflammatory stimuli, and in apoptotic cell death. Inhibition of PARP1 results in significant neuroprotection in PD animal models; moreover PARP1 has a physiological role in the regulation of alpha-synuclein expression. A previous study had demonstrated that variants located within the PARP1 gene promoter reduce the risk of PD and delay the disease age at onset. In light of these data, we carried out an association study to investigate whether variability within this gene is associated with PD risk and disease age at onset in an Italian cohort composed of 600 PD patients and 592 healthy controls. To this purpose, we used a comprehensive tag SNP approach spanning the entire gene and the upstream and downstream regions. We did not detect any significant association of the PARP1 gene with PD either at genotypic or haplotypic level; none of the 11 genotyped SNPs was significantly associated with PD age at onset. We conclude that, despite previous evidence, PARP1 is not a susceptibility gene for PD in our population.


Subject(s)
Genetic Predisposition to Disease/genetics , Parkinson Disease/genetics , Poly(ADP-ribose) Polymerases/genetics , Adult , Aged , Aged, 80 and over , Female , Genome-Wide Association Study , Genotype , Haplotypes , Humans , Male , Middle Aged , Poly (ADP-Ribose) Polymerase-1
11.
Neurobiol Aging ; 32(11): 2108.e1-5, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21782285

ABSTRACT

Sepiapterin reductase (SPR) gene is an enzyme which catalyses the final step of tetrahydrobiopterin synthesis (BH4) and was implicated in Parkinson's disease (PD) pathogenesis as a candidate gene for PARK3 locus. A number of studies yielded association of the PARK3 locus with PD, and SPR knockout mice were shown to display parkinsonian features. To evaluate the role of SPR gene polymorphisms in diverse populations in PD, we performed collaborative analyses in the Genetic Epidemiology of Parkinson Disease (GEO-PD) Consortium. A total of 5 single nucleotide polymorphisms (3 in the promoter region and 2 in the 3' untranslated region [UTR]) were genotyped. Fixed as well as random effect models were used to provide summary risk estimates of SPR variants. A total of 19 sites provided data for 6547 cases and 9321 controls. Overall odds ratio estimates varied from 0.92 to 1.01. No overall association with the SPR gene using either fixed effect or random effect model was observed in the studied population. I(2) Metric varied from 0% to 36.2%. There was some evidence for an association for participants of North European/Scandinavian descent with the strongest signal for rs1876487 (odds ratio = 0.82; p value = 0.003). Interestingly, families which were used to map the PARK3 locus, have Scandinavian ancestry suggesting a founder effect. In conclusion, this large association study for the SPR gene revealed no association for PD worldwide. However, taking the initial mapping of the PARK3 into account, the role of a population-specific effect warrants consideration in future studies.


Subject(s)
Alcohol Oxidoreductases/genetics , Genetic Loci/genetics , Parkinson Disease/genetics , Genetic Association Studies , Genetic Predisposition to Disease , Genotype , Humans , Polymorphism, Single Nucleotide , Promoter Regions, Genetic
12.
Alzheimer Dis Assoc Disord ; 25(2): 164-72, 2011.
Article in English | MEDLINE | ID: mdl-20921877

ABSTRACT

Alzheimer disease (AD) is the most prevalent neurodegenerative disease, characterized by an increased deposition of ß-amyloid (Abeta) within the central nervous system, leading to neuronal death. The availability of effective models, in which confirming novel pathogenic hypotheses and developing therapeutic targets, represents a very important goal for the field of AD. Fibroblasts from these patients may be relevant models in which addressing these issues, as they display biochemical alterations mirroring SNC ones. In this work, fibroblasts obtained from controls were studied after exposure to nonfibrillar Abeta 1-42, showing decreased glutamate uptake, similar to that observed in AD cells, in absence of transporters modifications. Nonfibrillar Abeta 1-42 was able to induce in control cells mitochondrial alterations and p38-phosphorylation, mirroring similar alterations found in AD fibroblasts. Under our experimental conditions, this treatment induced neither apoptosis nor necrosis. To investigate a putative role of p38-modulation in mediating nonfibrillar Abeta 1-42 toxicity, fibroblasts from controls were pretreated with retinoic-acid, and SB203580, a p38-inhibitor. These pretreatments prevented both p38-phosphorylation and glutamate uptake inhibition. Our results suggest that nonfibrillar Abeta 1-42 downregulates glutamate transporters activity interfering with p38-activation and mitochondrial stress. Thus, modulating complex kinase signaling pathway might represent a future therapeutic target in AD.


Subject(s)
Amyloid beta-Peptides/metabolism , Fibroblasts/metabolism , Glutamic Acid/metabolism , Peptide Fragments/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Aged , Aged, 80 and over , Alzheimer Disease/metabolism , Amino Acid Transport System X-AG/metabolism , Amyloid beta-Peptides/pharmacology , Blotting, Western , Cells, Cultured , Chromatography, High Pressure Liquid , Down-Regulation , Enzyme Activation/drug effects , Enzyme Activation/physiology , Female , Fibroblasts/drug effects , Fibroblasts/pathology , Humans , Male , Microscopy, Atomic Force , Middle Aged , Peptide Fragments/pharmacology , Phosphorylation , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects , Signal Transduction/physiology
13.
J Neural Transm (Vienna) ; 117(9): 1093-8, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20665056

ABSTRACT

Despite advances in neuroimaging, the diagnosis of idiopathic Parkinson's disease (PD) remains clinical. The identification of biological markers for an early diagnosis is of great interest to start a neuroprotective therapy aimed at slowing, blocking or reversing the disease progression. Vesicular monoamine transporter 2 (VMAT2) sequesters cytoplasmic dopamine into synaptic vesicles for storage and release. Thus, VMAT2 impairment can regulate intra- and extracellular dopamine levels, influencing oxidative stress and neuronal death. Because in vivo imaging studies have demonstrated a VMAT2 reduction in PD patients greater than would be explained by neuronal loss alone, as an exploratory study we assessed VMAT2 mRNA and protein levels in platelets from 39 PD patients, 39 healthy subjects and 10 patients with vascular parkinsonism (VP) to identify a possible peripheral biomarker for PD. A significant reduction (p < 0.05) of VMAT2 mRNA levels was demonstrated in PD patients versus healthy controls. Patients with VP showed VMAT2 mRNA levels similar to controls. No difference in VMAT2 mRNA levels was found in untreated versus treated patients. No correlation was observed between mRNA levels and demographic or clinical characteristics. Furthermore, eight SNPs tagging the VMAT2 gene did not show effects on VMAT2 mRNA levels. Western blot analysis did not allow the quantification of VMAT2 protein expression in blood platelets. Although further studies in a greater number of cases are needed to confirm our data, the reduction in VMAT2 mRNA in platelets from PD patients suggests the existence of a systemic impairment of this transporter possibly contributing to PD pathology.


Subject(s)
Blood Platelets/metabolism , Parkinson Disease/metabolism , Vesicular Monoamine Transport Proteins/metabolism , Aged , Analysis of Variance , Blotting, Western , Female , Genotype , Humans , Male , Middle Aged , Parkinson Disease/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Vesicular Monoamine Transport Proteins/genetics
14.
AIDS Res Hum Retroviruses ; 26(1): 41-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20055587

ABSTRACT

The patterns of transmitted drug-resistant (TDR) HIV-1 variants, non-B subtype spread, and epidemiological trends were evaluated either in seroconverters or in newly diagnosed individuals in Italy over a 13-year period. We analyzed 119 seroconverters, enrolled from 1992 to 2003 for the CASCADE study, and 271 newly diagnosed individuals of the SPREAD study (2002-2005), of whom 42 had a known seroconversion date. Overall, TDR was 15.1% in the CASCADE and 12.2% in the SPREAD study. In the 1992-2003 period, men having sex with men (MSMs) and heterosexuals (HEs) were 48.7% and 36.8%, respectively; TDR was found to be higher in MSMs compared to HEs (78.9% vs. 21%, p = 0.006). The same groups were 39.1% and 53.3% in the SPREAD study; however, no association was detected between modality of infection and TDR. Overall, 9.2% and 22.1% of individuals harbored a non-B clade virus in the CASCADE and SPREAD study, respectively. As evidence of onward transmission, 40% (24/60) of non-B variants were carried by European individuals in the latter study; among these patients the F1 subtype was highly prevalent (p = 0.00001). One of every eight patients who received a diagnosis of HIV-1 in recent years harbored a resistant variant, reinforcing the arguments for baseline resistance testing to customize first-line therapy in newly infected individuals. The spread of non-B clades may act as a dilution factor of TDR concealing the proportion of TDR in seroconverters and MSMs.


Subject(s)
Drug Resistance, Viral , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/classification , HIV-1/drug effects , Adolescent , Adult , Aged , Amino Acid Substitution/genetics , Female , Genotype , HIV Infections/diagnosis , HIV Infections/transmission , HIV Protease/genetics , HIV Reverse Transcriptase/genetics , HIV Seropositivity , HIV-1/isolation & purification , Humans , Italy/epidemiology , Male , Middle Aged , Prevalence , Sequence Analysis, DNA , Young Adult , pol Gene Products, Human Immunodeficiency Virus/genetics
15.
J Infect Dis ; 200(10): 1503-8, 2009 Nov 15.
Article in English | MEDLINE | ID: mdl-19835478

ABSTRACT

The SPREAD Programme investigated prospectively the time trend from September 2002 through December 2005 of transmitted drug resistance (TDR) among 2793 patients in 20 European countries and in Israel with newly diagnosed human immunodeficiency virus type 1 (HIV-1) infection. The overall prevalence of TDR was 8.4% (225 of 2687 patients; 95% confidence interval [CI], 7.4%-9.5%), the prevalence of nucleoside reverse-transcriptase inhibitor (NRTI) resistance was 4.7% (125 of 2687 patients; 95% CI, 3.9%-5.5%), the prevalence of nonucleoside reverse-transcriptase inhibitor (NNRTI) resistance was 2.3% (62 of 2687 patients; 95% CI, 1.8%-2.9%), and the prevalence of protease inhibitor (PI) resistance was 2.9% (79 of 2687 patients; 95% CI, 2.4%-3.6%). There was no time trend in the overall TDR or in NRTI resistance, but there was a statistically significant decrease in PI resistance (P = .04) and in NNRTI resistance after an initial increase (P = .02). We found that TDR appears to be stabilizing in Europe, consistent with recent reports of decreasing drug resistance and improved viral suppression in patients treated for HIV-1 infection.


Subject(s)
Drug Resistance, Viral , HIV Infections/epidemiology , HIV Infections/transmission , HIV-1/drug effects , Adult , Europe/epidemiology , Female , HIV Infections/drug therapy , HIV-1/genetics , Humans , Male , Middle Aged , Prevalence , Reverse Transcriptase Inhibitors/therapeutic use
16.
J Gen Virol ; 89(Pt 12): 3119-3125, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19008401

ABSTRACT

Recombination is recognized as a primary force in human immunodeficiency virus type 1 (HIV-1) evolution, increasing viral diversity through reshuffling of genomic portions. The strand-switching activity of reverse transcriptase is required to complete HIV-1 replication and can occur randomly throughout the genome, leading to viral recombination. Some recombination hotspots have been identified and found to correlate with RNA structure or sequence features. The aim of this study was to evaluate the presence of recombination hotspots in the pol gene of HIV-1 and to assess their correlation with the underlying RNA structure. Analysis of the recombination pattern and breakpoint distribution in a group of unique recombinant forms (URFs) detected two recombination hotspots in the pol region. Two stable and conserved hairpins were consistently predicted corresponding to the identified hotspots using six different RNA-folding algorithms on the URF parental strains. These findings suggest that such hairpins may play a role in the higher recombination rates detected at these positions.


Subject(s)
Gene Products, pol/genetics , Genes, pol , HIV-1/genetics , Recombination, Genetic , Gene Products, pol/chemistry , HIV Protease/genetics , HIV Reverse Transcriptase/genetics , Humans , Molecular Sequence Data , RNA, Viral/chemistry , RNA, Viral/genetics , Sequence Analysis, DNA
17.
AIDS Res Hum Retroviruses ; 24(10): 1319-25, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18851681

ABSTRACT

The HIV-1 subsubtype A1 epidemic of the former Soviet Union (FSU) was caused by an A1 variant apparently derived from a single introduction event. We identified an A1 variant highly related to the A1 lineage circulating in the FSU in a patient from Conakry, Republic of Guinea, who was diagnosed with HIV-1 when he moved to Italy in 2002. The most probable route of infection was two blood transfusions received in his country of origin in 1998. Full-length (9781 bp) molecular characterization revealed that this strain was evolutionarily parental to, but distinct from, the A1 lineage circulating in the FSU. Similar results were obtained analyzing partial genome sequences. A full-length sequence similarity plot and bootscanning analysis supported this evidence and excluded any potential recombination events with other HIV-1 variants. This viral strain represents the first evidence of an African patient infected by an A1 subtype related to the A1 variants spreading in FSU countries. The identification of this distinct A1 variant may support the origin of the Russian A epidemic from West Africa.


Subject(s)
HIV Infections/epidemiology , HIV Infections/virology , HIV-1/classification , HIV-1/genetics , RNA, Viral/genetics , Adult , Cluster Analysis , Genotype , Guinea , HIV-1/isolation & purification , Humans , Male , Molecular Epidemiology , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , USSR/epidemiology
18.
Clin Sci (Lond) ; 113(2): 103-8, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17362204

ABSTRACT

Diabetes mellitus accelerates atherosclerotic processes, and it is known that inflammation plays a key role in atherosclerosis. The aim of the present study was to evaluate in patients with Type 2 diabetes whether serum levels of CRP (C-reactive protein) are associated with cytokine production in whole blood. A total of 89 outpatients with Type 2 diabetes were enrolled, and blood pressure, body mass index, fasting blood glucose, glycated haemoglobin, cholesterol, triacylglycerols (triglycerides) and hs-CRP (high-sensitivity CRP) were measured. IL-6 (interleukin-6), IL-1beta (interleukin-1beta) and TNF-alpha (tumour necrosis factor-alpha) were measured before and after 24 h of incubation of whole blood with LPS (lipopolysaccharide) or saline. The basal values of IL-1beta, IL-6 and TNF-alpha were low and were not significantly related to hs-CRP levels. A univariate analysis showed that the level of IL-1beta and IL-6, obtained after 24 h of incubation of whole blood with LPS, increased significantly with increasing levels of hs-CRP and, after adjusting for potential confounders, IL-1beta still remained statistically significant. In our sample of patients with Type 2 diabetes, there was no association between serum hs-CRP levels and basal levels of IL-6, IL-1beta and TNF-alpha. Conversely, a significant association was observed between serum hs-CRP levels and IL-1beta and IL-6 production after 24 h of incubation of whole blood with LPS. In conclusion, our data suggest that patients with Type 2 diabetes and high hs-CRP levels may have an enhanced reactivity in response to specific stimuli that produce different interleukins, with possible implications in inflammatory atherosclerotic processes.


Subject(s)
C-Reactive Protein/analysis , Cytokines/biosynthesis , Cytokines/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/immunology , Aged , Female , Humans , Interleukin-1beta/blood , Interleukin-6/blood , Linear Models , Lipopolysaccharides/pharmacology , Male , Middle Aged , Multivariate Analysis , Tumor Necrosis Factor-alpha/blood
19.
AIDS ; 20(4): 567-74, 2006 Feb 28.
Article in English | MEDLINE | ID: mdl-16470121

ABSTRACT

BACKGROUND: Vpr (viral protein R) is a 96 amino acids soluble protein that is expressed late during viral replication. Recent studies have focused on the role of a mutation at position 77 that might be associated with the condition of long-term non-progression, but data are still controversial. PATIENTS AND METHODS: Fifteen long-term non-progressors (LTNP), 19 therapy-naive HIV-1-infected patients with progressive disease (Pr), 23 HIV-1-infected patients receiving sub-optimal therapy with dual nucleoside [nucleoside reverse transcriptase inhibitor (NRTI)] therapy but efficiently controlling viral replication (STP) and 19 antiretroviral therapy multi-experienced patients with actively replicating virus (MEP) were analysed. HIV-RNA was extracted from plasma samples, the Vpr region was amplified, cloned and sequenced. The Pol gene was amplified, directly sequenced and analysed using Sequence Navigator software. RESULTS: A significantly higher prevalence of the R77Q mutation was evidenced both in LTNP (86.7%) and STP (73.9%) in comparison with Pr (42.1%) and MEP (42.1%), (P = 0.007). Comparing groups of patients with progressive disease (Pr + MEP) and groups with non-progressive disease (LTNP + STP) the probability of harbouring the R77Q mutation was significantly higher in non-progressors (odds ratio, 5.16; P = 0.001). CONCLUSIONS: Our results support the hypothesis of the association of R77Q mutation in the Vpr gene with delayed progression of HIV-1 disease. R77Q does not seem to be linked to a particular viral strain but might be associated to immunologic selection. The R77Q mutation might reduce CD4+ T-cell depletion possibly affecting T-cell survival in vivo by altering the pro-apoptotic activity of Vpr.


Subject(s)
Genes, vpr/genetics , HIV Infections/genetics , HIV-1/genetics , Mutation/genetics , Adult , Antiretroviral Therapy, Highly Active , Disease Progression , Female , Genes, pol/genetics , Genotype , HIV Infections/drug therapy , HIV Long-Term Survivors , Humans , Male , RNA, Viral/genetics , Random Allocation , Viral Load , Virus Replication/genetics
20.
J Med Virol ; 75(4): 483-90, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15714483

ABSTRACT

A total of 347 pol gene sequences from 88 Tuscan and 259 Apulian subjects (including 52 non-Italians and 9 children) were analyzed phylogenetically. Forty-four (12.6%) non-B subtypes were found, including 3.4% C, 1.4% F1, 0.8% G, and 0.3% each for J and A pure subtypes, and 3.7% CRF02_AG, 1.4% CRF01_AE, 0.6% BF, and 0.3% CRF06-cpx recombinant forms. An additional sample close-matched the pol gene of an unique recombinant form (URF AGK 99GR303). The non-B subtypes were from 40 adults and 4 children; 12 of these 44 patients were epidemiologically linked. Thirty-three of the 44 non-B viruses pertained to non-Italian immigrants and 11 to Italians, signifying that 63.4% immigrants and 3.7% Italians harbored non-B subtypes. The overall frequency of non-B subtypes was higher in Tuscany than in Apulia (18.1% vs. 10.8%). Moreover, 6.1% and 3.0% non-B subtypes were found among Italians from Florence and Apulia, respectively, while 52.1% and 72.4% of immigrants living in Tuscany and Apulia harbored non-B subtypes. Women infected by means of sexual contact prevailed among non-Italian adults; the majority of Italians were males and admitted high-risk sexual behavior. Four Italians had a history of extensive travel in countries of high endemicity. Social and epidemiological changes are responsible for an increasing circulation of non-B subtypes in Italy. Although non-B subtypes principally infect non-Italian patients, in Italy they can no longer be considered exclusively restricted to subjects from endemic areas.


Subject(s)
HIV Infections/epidemiology , HIV Infections/virology , HIV-1/classification , Phylogeny , Recombination, Genetic , Adolescent , Adult , Child , Child, Preschool , Emigration and Immigration , Female , Gene Products, pol/genetics , HIV-1/genetics , Humans , Italy/epidemiology , Male , Middle Aged , Molecular Sequence Data , Sequence Analysis, DNA
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