Lucia Migliore

Università di Pisa, Pisa, Tuscany, Italy

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Publications (47)151.92 Total impact

  • Article: Multiple cytotoxic and genotoxic effects induced in vitro by differently shaped copper oxide nanomaterials.
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    ABSTRACT: In nanotoxicology, the capacity of nanoparticles of the same composition but different shape to induce cytotoxicity and genotoxicity is largely unknown. A series of cytotoxic and genotoxic responses following in vitro exposure to differently shaped CuO nanoparticles (CuO NPs, mass concentrations from 0.1 to 100 μg/ml) were assessed in murine macrophages RAW 264.7 and in peripheral whole blood from healthy volunteers. Cytotoxicity, cytostasis and genotoxicity were evaluated by the colorimetric assay of formazan reduction [3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT)] and by the cytokinesis-block micronucleus cytome (CBMN Cyt) assay. The comet assay was applied for detecting DNA strand breaks and information on oxidative damage to DNA (oxidised purines and pyrimidines). The MTT assay revealed a decrease in cell viability in RAW 264.7 cells and peripheral blood lymphocytes (PBL) with significant dose-effect relationships for the different CuO NP shapes. The comet assay revealed a dose-dependent increase in primary DNA damage, and a significant increase in oxidative damage to DNA was also detectable, as well as increased frequency of micronuclei in binucleated cells, often in a dose-related manner. Proliferative activity, cytotoxicity and apoptotic markers showed a significant trend in the two cell types. Finally, we have differentiated clastogenic events from aneugenic events by fluorescence in situ hybridisation with human and murine pancentromeric probes, revealing for the first time characteristic aneugenic responses related to the shape of CuO NPs and cell type. Independently of size and shape, all CuO NPs revealed a clear-cut cytotoxic and genotoxic potential; this suggests that CuO NPs are good candidates for positive controls in nanotoxicology.
    Mutagenesis 03/2013; · 3.18 Impact Factor
  • Article: Comparison Study of MS-HRM and Pyrosequencing Techniques for Quantification of APC and CDKN2A Gene Methylation.
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    ABSTRACT: There is increasing interest in the development of cost-effective techniques for the quantification of DNA methylation biomarkers. We analyzed 90 samples of surgically resected colorectal cancer tissues for APC and CDKN2A promoter methylation using methylation sensitive-high resolution melting (MS-HRM) and pyrosequencing. MS-HRM is a less expensive technique compared with pyrosequencing but is usually more limited because it gives a range of methylation estimates rather than a single value. Here, we developed a method for deriving single estimates, rather than a range, of methylation using MS-HRM and compared the values obtained in this way with those obtained using the gold standard quantitative method of pyrosequencing. We derived an interpolation curve using standards of known methylated/unmethylated ratio (0%, 12.5%, 25%, 50%, 75%, and 100% of methylation) to obtain the best estimate of the extent of methylation for each of our samples. We observed similar profiles of methylation and a high correlation coefficient between the two techniques. Overall, our new approach allows MS-HRM to be used as a quantitative assay which provides results which are comparable with those obtained by pyrosequencing.
    PLoS ONE 01/2013; 8(1):e52501. · 4.09 Impact Factor
  • Article: Epigenetic effects of nano-sized materials.
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    ABSTRACT: The term epigenetics includes several phenomena such as DNA methylation, histone tail modifications, and microRNA mediated mechanisms, which are able to mold the chromatin structure and/or gene expression levels, without altering the primary DNA sequence. Environmental agents can exert epigenetic properties and there is increasing evidence of epigenetic deregulation of gene expression in several human diseases, including cancer, cardiovascular diseases, autism spectrum disorders, autoimmune diseases, and neurodegeneration, among others. Given the widespread use and dispersion in the environment of nano-sized materials, this article summarizes the studies performed so far to evaluate their potential epigenetic properties. Those studies highlight the ability of certain nano-sized compounds to induce an impaired expression of genes involved in DNA methylation reactions leading to global DNA methylation changes, as well as changes of gene specific methylation of tumor suppressor genes, inflammatory genes, and DNA repair genes, all potentially involved in cancer development. Moreover, some nano-sized compounds are able to induce changes in the acetylation and methylation of histone tails, as well as microRNA deregulated expression. We also provided a detailed description of currently available methodologies to evaluate epigenetic modifications. Standard protocols are currently available to evaluate cytotoxic and genotoxic effects of nano-sized materials. By contrast, there are at present no available standard protocols to evaluate the epigenetic potential of any given compound. The currently available methodologies offer different, but often complementary information to characterize potential epigenetic changes induced by exposure to nano-sized compounds. Given the widespread use and dispersion in the environment of nano-sized materials, at present and foreseeable in the near future, and in light of the indication of potential epigenetic properties here reviewed, more attention should be paid to unravel the consequences of such effects in future studies.
    Toxicology 12/2012; · 3.68 Impact Factor
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    Article: DNMT3B promoter polymorphisms and maternal risk of birth of a child with Down syndrome.
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    ABSTRACT: STUDY QUESTION: Are DNMT3B promoter polymorphisms among maternal risk factors for the birth of a child with Down syndrome (DS)? SUMMARY ANSWER: Present results suggest that combinations of functional DNMT3B promoter polymorphisms might modulate maternal risk of birth of a child with DS. WHAT IS KNOWN ALREADY: The DNMT3B gene codes for DNA methyltransferase 3b (DNMT3b), a protein required for genome-wide de novo methylation, for the establishment of DNA methylation patterns during development and for regulating the histone code and DNA methylation at centromeric regions. Two common functional DNMT3B promoter polymorphisms, namely -149 C > T (rs2424913) and -579 G > T (rs1569686), have been extensively investigated in cancer genetic association studies but less is known about their role in non-cancer diseases. Early in 1999, it was supposed that impaired DNA methylation of pericentromeric regions might represent a maternal risk factor for having a baby with DS. STUDY DESIGN, SIZE AND DURATION: We aimed to investigate DNMT3B -149 C > T and -579 G > T polymorphisms as maternal risk factors for the birth of a child with DS. The study was performed on DNA samples from 172 mothers of DS individuals (135 aged <35 years when they conceived) and 157 age-matched mothers of unaffected individuals. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Genotyping was performed by means of the PCR-RFLP technique. MAIN RESULTS AND THE ROLE OF CHANCE: The DNMT3B -579T allele [odds ratio (OR) = 0.68; 95% confidence interval (CI) = 0.48-0.94, P = 0.02], the DNMT3B -579 GT genotype (OR = 0.55; 95% CI = 0.35-0.87 , P = 0.01) and the combined DNMT3B -579 GT + TT genotype (OR = 0.55; 95% CI = 0.36-0.86 , P = 0.008) were associated with reduced risk of birth of a child with DS. A joint effect of the two polymorphisms was observed and the combined -579 GT/-149 CC genotype resulted in decreased DS risk (OR = 0.22; 95% CI = 0.08-0.64, P = 0.003). The effect remained statistically significant after Bonferroni's correction for multiple comparisons. Similar results were obtained when the analysis was restricted to women who conceived a DS child before 35 years of age. LIMITATIONS AND REASONS FOR CAUTION: To the best of our knowledge, this is the first genetic association study aimed at evaluating DNMT3B polymorphisms as maternal risk factors for DS. Replication of the findings in other populations is required. WIDER IMPLICATIONS OF THE FINDINGS: If confirmed in subsequent studies, DNMT3B promoter polymorphisms might be additional markers to be taken into account when evaluating the contribution of one-carbon (folate) metabolism to the maternal risk of birth of a child with DS. STUDY FUNDING/COMPETING INTEREST(S): None of the authors has any competing interest. This work was partially supported by the Italian Ministry of Health and '5 per mille' funding.
    Human Reproduction 10/2012; · 4.47 Impact Factor
  • Article: Folate, homocysteine, vitamin B12, and polymorphisms of genes participating in one-carbon metabolism in late-onset Alzheimer's disease patients and healthy controls.
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    ABSTRACT: We screened 378 late-onset Alzheimer's disease (LOAD) patients and 308 matched controls for the presence of the common MTHFR 677C>T, MTRR 66A>G, MTR 2756 A>G, and TYMS 28 bp repeat polymorphisms, searching for association with disease risk and age at onset. Moreover, we searched for correlation between each of the studied polymorphisms and available data on plasma homocysteine (Hcy), serum folate, and vitamin B12 values. We observed a significant increased frequency of the MTHFR 677T allele (0.48 vs. 0.42; p=0.019) and of MTHFR 677CT (OR=1.46; 95%CI=1.03-2.06) and TT genotypes (OR=1.62; 95%CI=1.05-2.49) in LOAD subjects with respect to controls. We also observed a significant increased frequency of the MTRR 66G allele (0.49 vs. 0.43; p=0.044) and of the MTRR 66GG genotype (OR=1.57; 95%CI=1.01-2.46) in the LOAD group. Significantly increased mean plasma Hcy levels (22.7±1.7 vs 14.5±1.7 μmol/L; p=0.037) and decreased serum folate values (5.7±0.5 vs. 7.8±0.8 ng/mL; p=0.005) were observed in LOAD subjects with respect to controls, whilst the difference in serum vitamin B12 values did not reach statistical significance. Several interactions between the studied polymorphisms and biochemical biomarkers were observed. None of the studied polymorphisms was associated with disease age at onset. Innovation: The present study suggests that the MTRR 66G allele might contribute to LOAD risk and confirms an increased frequency of the MTHFR 677T allele in LOAD. Overall, present results support a contribution for one-carbon metabolism to LOAD pathogenesis.
    Antioxidants & Redox Signaling 12/2011; 17(2):195-204. · 8.20 Impact Factor
  • Article: Association of micronucleus frequency with neurodegenerative diseases.
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    ABSTRACT: Micronuclei (MNi) can originate either from chromosome breakage or chromosome malsegregation events and are therefore ideal biomarkers to investigate genomic instability. Studies in peripheral lymphocytes of patients with neurodegenerative diseases, mainly Alzheimer's disease (AD) and Parkinson's disease (PD), revealed an increased micronucleus (MN) frequency in both disorders but originating mainly from chromosome malsegregation events in AD and from chromosome breakage events in PD. Studies in other neurodegenerative diseases are largely missing, and some data in premature ageing disorders characterised by neurodegeneration and/or neurological complications, such as Ataxia telangiectasia, Werner's syndrome, Down's syndrome (DS) and Cockayne's syndrome, indicate that MNi increase with ageing in cultured cells. An increased frequency of aneuploidy characterises several tissues of AD patients, as well as of individuals at increased risk to develop AD, such as mothers of DS individuals and DS subjects themselves. The use of the buccal MN cytome assay in AD and DS subjects allowed finding significant changes in the MN frequency as well as other cellular modifications reflecting reduced regenerative capacity compared to age- and gender-matched controls. These changes in buccal cytome ratios may prove useful as potential future diagnostics to identify individuals of increased risk for these disorders.
    Mutagenesis 01/2011; 26(1):85-92. · 3.18 Impact Factor
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    Article: Genetics, cytogenetics, and epigenetics of colorectal cancer.
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    ABSTRACT: Most of the colorectal cancer (CRC) cases are sporadic, only 25% of the patients have a family history of the disease, and major genes causing syndromes predisposing to CRC only account for 5-6% of the total cases. The following subtypes can be recognized: MIN (microsatellite instability), CIN (chromosomal instability), and CIMP (CpG island methylator phenotype). CIN occurs in 80-85% of CRC. Chromosomal instability proceeds through two major mechanisms, missegregation that results in aneuploidy through the gain or loss of whole chromosomes, and unbalanced structural rearrangements that lead to the loss and/or gain of chromosomal regions. The loss of heterozygosity that occur in the first phases of the CRC cancerogenesis (in particular for the genes on 18q) as well as the alteration of methylation pattern of multiple key genes can drive the development of colorectal cancer by facilitating the acquisition of multiple tumor-associated mutations and the instability phenotype.
    Journal of Biomedicine and Biotechnology 01/2011; 2011:792362. · 2.44 Impact Factor
  • Article: Carbon nanotubes induce oxidative DNA damage in RAW 264.7 cells.
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    ABSTRACT: The induction of DNA and chromosome damage following in vitro exposure to carbon nanotubes (CNT) was assessed on the murine macrophage cell line RAW 264.7 by means of the micronucleus (MN) and the comet assays. Exposures to two CNT preparations (single-walled CNT (SWCNT > 90%) and multiwalled CNT (MWCNT > 90%) were performed in increasing mass concentrations (0.01-100 microg/ml). The frequency of micronuclei was significantly increased in cells treated with SWCNT (at doses above 0.1 microg/ml), whereas MWCNT had the same effect at higher concentrations (1 microg/ml) (P < 0.05). The results of the comet assay revealed that the effects of treatment with SWCNT were detectable at all concentrations tested (1-100 microg/ml); oxidized purines increased significantly, whereas pyrimidines showed a significant increase (P < 0.001) only at the highest concentration (100 microg/ml). In cells treated with MWCNT, an increase in DNA migration due to the oxidative damage to purines was observed at a concentration of 1 and 10 microg/ml, whereas pyrimidines showed a significant increase only at the highest mass concentration tested. However, both SWCNT and MWCNT induced a statistically significant cytotoxic effect at the highest concentrations tested (P < 0.001). These findings suggest that both the MN and comet assays can reliably detect small amount of damaged DNA at both chromosome and nuclear levels in RAW 264.7 cells. Moreover, the modified version of the comet assay allows the specific detection of the induction of oxidative damage to DNA, which may be the underlying mechanism involved in the CNT-associated genotoxicity.
    Environmental and Molecular Mutagenesis 05/2010; 51(4):294-303. · 3.71 Impact Factor
  • Article: Evidence linking genetics, environment, and epigenetics to impaired DNA repair in Alzheimer's disease.
    Fabio Coppedè, Lucia Migliore
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    ABSTRACT: Increasing evidence suggests that the repair of DNA lesions, particularly oxidative DNA lesions, might be compromised in Alzheimer's disease (AD). Studies performed in brains and peripheral tissues of both AD patients and individuals affected by mild cognitive impairment (MCI) revealed that oxidative DNA damage is one of the earliest detectable events during the progression from healthy aging to dementia. Moreover, the increase in DNA damage is paralleled by a decrease in DNA repair activities. Several hypotheses are currently tested in order to explain the decreased DNA repair activity observed in MCI and AD subjects. Some authors have suggested that mutations or polymorphisms in DNA repair genes might impair DNA repair. However, this hypothesis does not seem to be confirmed by recent genetic association studies. Others suggest that DNA repair proteins might be inactivated by oxidative induced post-translational modifications or degradation. There is also indication that different isoforms of the same repair protein might be involved in the progression from early to late stages AD. Moreover, a widespread activation of DNA repair pathways might generate death signals ending with neuronal apoptosis. A link between environmental induced epigenetic modification, oxidation, and repair of AD related genes has been also proposed. Most of these studies have been performed during the last few years, and we are still at the beginning of understanding the complex interplay between oxidative DNA damage, DNA repair, and neuronal death in the brain leading to Alzheimer's dementia, making this topic an exciting and promising field for future investigation.
    Journal of Alzheimer's disease: JAD 02/2010; 20(4):953-66. · 3.74 Impact Factor
  • Article: The hOGG1 Ser326Cys polymorphism is not associated with sporadic Parkinson's disease.
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    ABSTRACT: Parkinson's disease (PD) is one of the most common neurodegenerative disorders characterized by progressive and profound loss of dopaminergic neurons in the substantia nigra (SN) resulting in resting tremor, rigidity, bradykinesia, and postural instability. The primary cause of the disease is still unknown, but mitochondrial dysfunction and oxidative stress have been implicated in the neurodegenerative process. Oxoguanine DNA glycosylase (OGG1) removes oxidized guanine (8-oxo-G) from the DNA, thus reducing the mutagenic potential of this modified base. Increased 8-oxo-G levels and up-regulation of OGG1 have been detected in the SN of PD brains. Moreover, studies performed in OGG1 knockout mice revealed the importance of this enzyme in protecting dopaminergic neurons against the accumulation of oxidative DNA damage. A common Ser326Cys polymorphism is known in the human gene encoding OGG1 (hOGG1), and the mutant Cys326 variant has been associated with reduced glycosylase activity. In the present study we screened 139 sporadic PD patients and 211 healthy matched controls for the presence of the hOGG1 Ser326Cys polymorphism. The Cys326 allele frequency was similar between the groups (0.20 in PD patients and 0.19 in controls; p=0.817), and no difference in genotype frequencies was observed. Moreover, the hOGG1 Ser326Cys polymorphism was not associated with disease age at onset (p=0.791). Overall, present results suggest that the hOGG1 Ser326Cys polymorphism is not associated with sporadic PD.
    Neuroscience Letters 02/2010; 473(3):248-51. · 2.11 Impact Factor
  • Article: DNA repair in premature aging disorders and neurodegeneration.
    Fabio Coppedè, Lucia Migliore
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    ABSTRACT: The accumulation of DNA damage has been widely implicated in premature aging and neurodegeneration. Progeroid syndromes with defects in the cellular response to DNA damage suggest that progressive genome instability represents an important aspect of the aging process. Moreover, most of the major neurodegenerative diseases are characterized by the accumulation of neuronal DNA damage, suggesting that impaired DNA repair mechanisms might be relevant to both premature aging and neurodegeneration. Two progeroid syndromes, Hutchinson-Gilford progeria syndrome and Werner's syndrome, are characterized by clinical features mimicking physiological aging at an early age and molecular studies have implicated decreased cell proliferation and altered DNA-damage responses as common causal mechanisms in the pathogenesis of both diseases. Defects in nucleotide excision repair cause three distinct human diseases: xeroderma pigmentosum, Cockayne's syndrome and trichothiodystrophy; each of them is characterized by premature onset of pathologies that overlap with those associated with old age in humans. Increasing evidence also suggests that an impaired DNA repair, particularly the base excision repair pathway, might play a fundamental role in the development of age-related neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and Huntington' s disease. Here, we review the current knowledge on the role of DNA repair in premature aging and neurodegenerative diseases.
    Current Aging Science 02/2010; 3(1):3-19.
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    Article: Polymorphisms in folate-metabolizing genes, chromosome damage, and risk of Down syndrome in Italian women: identification of key factors using artificial neural networks.
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    ABSTRACT: Studies in mothers of Down syndrome individuals (MDS) point to a role for polymorphisms in folate metabolic genes in increasing chromosome damage and maternal risk for a Down syndrome (DS) pregnancy, suggesting complex gene-gene interactions. This study aimed to analyze a dataset of genetic and cytogenetic data in an Italian group of MDS and mothers of healthy children (control mothers) to assess the predictive capacity of artificial neural networks assembled in TWIST system in distinguish consistently these two different conditions and to identify the variables expressing the maximal amount of relevant information to the condition of being mother of a DS child.The dataset consisted of the following variables: the frequency of chromosome damage in peripheral lymphocytes (BNMN frequency) and the genotype for 7 common polymorphisms in folate metabolic genes (MTHFR 677C>T and 1298A>C, MTRR 66A>G, MTR 2756A>G, RFC1 80G>A and TYMS 28bp repeats and 1494 6bp deletion). Data were analysed using TWIST system in combination with supervised artificial neural networks, and a semantic connectivity map. TWIST system selected 6 variables (BNMN frequency, MTHFR 677TT, RFC1 80AA, TYMS 1494 6bp +/+, TYMS 28bp 3R/3R and MTR 2756AA genotypes) that were subsequently used to discriminate between MDS and control mothers with 90% accuracy. The semantic connectivity map provided important information on the complex biological connections between the studied variables and the two conditions (being MDS or control mother). Overall, the study suggests a link between polymorphisms in folate metabolic genes and DS risk in Italian women.
    BMC Medical Genomics 01/2010; 3:42. · 3.69 Impact Factor
  • Article: The hOGG1 Ser326Cys polymorphism and Huntington's disease.
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    ABSTRACT: Increasing evidence supports a role for oxidative DNA damage and impaired DNA repair mechanisms in the pathogenesis of age related neurodegenerative diseases. Within this context there is a current interest in the understanding of the role played by polymorphisms of DNA repair genes in the inter-individual risk to develop neurodegenerative pathologies, as well as in the onset and the progression of disease symptoms. Particularly, somatic CAG repeat expansion of the gene encoding for huntingtin has been observed in tissues of patients affected by Huntington's disease (HD), including blood and brain. Recent evidence suggests that somatic CAG repeat expansion in HD cells might contribute to disease age at onset and is mediated by the DNA repair OGG1 enzyme, during the removal of 8-oxoguanine (8-oxoG) from the DNA. There is also evidence that the expression of hMTH1, which removes 8-oxoG from the nucleotide pool, protects mice from HD-like symptoms, and progenitor striatal cells from the toxic effects of the mutant huntingtin. The hOGG1 Ser326Cys polymorphism results in reduced OGG1 activity and increased 8-oxoG formation. In the present study, performed on blood DNA from 91 HD subjects, we observed that bearers of the mutant Cys326 allele (Ser326Cys+Cys326Cys) tend to have an increased number of CAG repeats of the expanded HD allele (P=0.049); moreover bearers of at least one copy of the mutant Cys326 allele, mainly heterozygous subjects, showed a significant (P=0.041) earlier disease onset than Ser326Ser wild-type individuals, suggesting a possible role of the hOGG1 Ser326Cys polymorphism in HD phenotype.
    Toxicology 10/2009; 278(2):199-203. · 3.68 Impact Factor
  • Article: Association study between XRCC1 gene polymorphisms and sporadic amyotrophic lateral sclerosis.
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    ABSTRACT: The aim of the present study was to investigate the possible contribution of three common functional polymorphisms in the DNA repair protein X-ray repair cross-complementing group 1 (XRCC1), namely Arg194Trp (rs1799782), Arg280His (rs25489) and Arg399Gln (rs25487), to sporadic amyotrophic lateral sclerosis (SALS). We genotyped 206 Italian SALS patients and 203 matched controls for XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphisms by means of PCR/RFLP technique, searching for association between any of the studied polymorphisms and disease risk, age and site of onset. We observed a statistically significant difference in XRCC1 Gln399 allele frequencies between SALS cases and controls (0.39/0.28; p=0.001). The present study suggests that the XRCC1 Arg399Gln polymorphism might contribute to SALS risk.
    Amyotrophic Lateral Sclerosis 09/2009; 11(1-2):122-4. · 3.40 Impact Factor
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    Article: DNA damage and repair in Alzheimer's disease.
    Fabio Coppedè, Lucia Migliore
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    ABSTRACT: The vast majority of the studies performed so far and aimed at elucidating DNA repair mechanisms has been performed in mitotic cells, such as transformed or cancer cell lines. Therefore, our understanding of DNA repair mechanisms in post-mitotic cells, such as neurons, remains one of the most exciting areas for future investigations. Markers of DNA damage, particularly oxidative DNA damage, have been largely found in brain regions, peripheral tissues, and biological fluids of Alzheimer's disease (AD) patients. Moreover, recent studies from our and other groups in individuals affected by Mild Cognitive Impairment provided evidence that oxidative DNA damage is one of the earliest detectable events within the progression from a normal brain to dementia. Almost one decade ago a decrease in the DNA base excision repair (BER) activity was observed in post mortem brain regions of AD individuals, leading to the hypothesis that the brain in AD might be subjected to the double insult of increased DNA damage, as well as deficiencies of DNA repair pathways. Subsequent studies have provided accumulating evidence of impaired DNA repair in AD. Moreover, functional variants and polymorphisms of DNA repair genes have been the focus of several cancer association studies, but only in recent years some of them have been investigated as possible AD risk factors. The few studies performed so far suggest that some variants might play a role in AD pathogenesis and deserve further investigations. Here, we summarize the current knowledge of DNA damage and repair in AD pathogenesis.
    Current Alzheimer research 03/2009; 6(1):36-47. · 4.97 Impact Factor
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    Article: Susceptibility to aneuploidy in young mothers of Down syndrome children.
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    ABSTRACT: We recently observed an increased frequency of binucleated micronucleated lymphocytes in women who had a Down syndrome (DS) child before 35 years of age and the fluorescence in situ hybridization analysis revealed that micronuclei were mainly originating from chromosomal malsegregation events, including chromosome 21 malsegregation. That study indicated that women who have a DS child at a young age might have a genetic predisposition to chromosome malsegregation in both somatic and germ line cells. Further studies from our group confirmed increased chromosome damage in blood cells of women who had a DS child at a young age and pointed to a possible role for polymorphisms in folate-metabolizing genes in affecting both chromosome damage and DS risk. In the present article, we review the most recent findings on mechanisms and risk factors for chromosome 21 nondisjunction that lead to DS. Multiple risk factors are likely involved in chromosome nondisjunction; they act at different times in the meiotic process and can be of genetic or environmental (epigenetic) origin. We also discuss the increased risk of developing Alzheimer's disease (AD) later in life that was observed in women who had a DS child at a young age. Studies performed in the last years that have shown that the brain is, in fact, a complex genetic mosaic of aneuploid and euploid cells support the unified hypothesis trying to relate DS, trisomy 21, and AD.
    TheScientificWorldJOURNAL 01/2009; 9:1052-60. · 1.66 Impact Factor
  • Article: Environmental-induced oxidative stress in neurodegenerative disorders and aging.
    Lucia Migliore, Fabio Coppedè
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    ABSTRACT: The aetiology of most neurodegenerative disorders is multifactorial and consists of an interaction between environmental factors and genetic predisposition. Free radicals derived primarily from molecular oxygen have been implicated and considered as associated risk factors for a variety of human disorders including neurodegenerative diseases and aging. Damage to tissue biomolecules, including lipids, proteins and DNA, by free radicals is postulated to contribute importantly to the pathophysiology of oxidative stress. The potential of environmental exposure to metals, air pollution and pesticides as well as diet as risk factors via the induction of oxidative stress for neurodegenerative diseases and aging is discussed. The role of genetic background is discussed on the light of the oxidative stress implication, focusing on both complex neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis) and monogenic neurological disorders (Huntington's disease, Ataxia telangiectasia, Friedreich Ataxia and others). Emphasis is given to role of the repair mechanisms of oxidative DNA damage in delaying aging and protecting against neurodegeneration. The emerging interplay between environmental-induced oxidative stress and epigenetic modifications of critical genes for neurodegeneration is also discussed.
    Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 11/2008; 674(1-2):73-84. · 2.85 Impact Factor
  • Article: Genetics, environmental factors and the emerging role of epigenetics in neurodegenerative diseases.
    Lucia Migliore, Fabio Coppedè
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    ABSTRACT: In the present review we summarize recent advances in the understanding of the interaction between genetics and environmental factors involved in complex multi-factorial neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD) and Amyotrophic Lateral Sclerosis (ALS). The discovery of several genes responsible for the familial forms has led to a better comprehension of the molecular pathways involved in the selective neuronal degeneration which is specific for each of these disorders. However, the vast majority of the cases occurs as sporadic forms, likely resulting from complex gene-gene and gene-environment interplay. Several environmental factors, including, pesticides, metals, head injuries, lifestyles and dietary habits have been associated with increased disease risk or even with protection. Hundreds of genetic variants have been investigated as possible risk factors for the sporadic forms, but results are often conflicting, not repeated or inconclusive. New approaches to environmental health research are revealing us that at the basis there could be chemically induced changes in gene regulation and emphasise the importance of understanding the susceptibility of the human epigenome to dietary and other environmental effects.
    Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 11/2008; 667(1-2):82-97. · 2.85 Impact Factor
  • Article: Association of maternal polymorphisms in folate metabolizing genes with chromosome damage and risk of Down syndrome offspring.
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    ABSTRACT: We analyzed the role of six common polymorphisms in folate metabolizing genes as possible risk factors for having a child with Down syndrome (DS) in 94 Italian mothers of a DS child (MDS) and 113 matched control mothers, both aged less than 35 years at conception. Investigated polymorphisms include methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C, methionine synthase (MTR) 2756A>G, methionine synthase reductase (MTRR) 66A>G, and thymidylate synthase (TYMS) 28bp repeat and 1494del6. We also measured the amount of chromosome damage in peripheral blood lymphocytes of 42 MDS and 41 matched controls, by means of the micronucleus assay, and searched for association between this cytogenetic endpoint and any of the studied polymorphisms. Micronuclei in peripheral blood lymphocytes have been analyzed several years after conception: the mean age at sampling was 45.6+/-11.4 years for MDS and 47.95+/-6.9 years for controls. The combined MTHFR 677TT/MTR 2756AA genotype was associated with increased DS risk (P=0.034), and the combined MTHFR 1298AC/TYMS 2R/2R genotype with reduced risk (P=0.003). Moreover, we observed a significant increased frequency of micronucleated lymphocytes in MDS as compared to controls (P<0.0001) and, in the total population, a significant correlation between micronucleated cells and both MTHFR 677C>T (P=0.031) and 1298A>C (P=0.047) polymorphisms.
    Neuroscience Letters 11/2008; 449(1):15-9. · 2.11 Impact Factor
  • Article: Lack of association between the APEX1 Asp148Glu polymorphism and sporadic amyotrophic lateral sclerosis.
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    ABSTRACT: Impairments in DNA repair enzymes have been observed in amyotrophic lateral sclerosis (ALS) tissues, particularly in the activity of the apurinic/apyrimidinic endonuclease 1 (APEX1). Moreover, it was suggested that the common APEX1 Asp148Glu polymorphism might be associated with ALS risk. To further address this question we performed the present study aimed at evaluating the contribution of the APEX1 Asp148Glu polymorphism in sporadic ALS (sALS) risk and clinical presentation, including age and site of onset and disease progression. We screened 134 sALS Italian patients and 129 matched controls for the presence of the APEX1 Asp148Glu polymorphism. No difference in APEX1 Asp148Glu allele and genotype frequencies was found between the groups, nor was the polymorphism associated with age and site of onset or disease progression. Present results do not support a role for the APEX1 Asp148Glu polymorphism in sALS pathogenesis in the Italian population.
    Neurobiology of aging 06/2008; 31(2):353-5. · 5.94 Impact Factor