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1.
Int J Mol Sci ; 24(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38003659

RESUMO

Polyamines (Pas) are short molecules that exhibit two or three amine groups that are positively charged at a physiological pH. These small molecules are present in high concentrations in a wide variety of organisms and tissues, suggesting that they play an important role in cellular physiology. Polyamines include spermine, spermidine, and putrescine, which play important roles in age-related diseases that have not been completely elucidated. Aging is a natural process, defined as the time-related deterioration of the physiological functions; it is considered a risk factor for degenerative diseases such as cardiovascular, neurodegenerative, and musculoskeletal diseases; arthritis; and even cancer. In this review, we provide a new perspective on the participation of Pas in the cellular and molecular processes related to age-related diseases, focusing our attention on important degenerative diseases such as Alzheimerߣs disease, Parkinsonߣs disease, osteoarthritis, sarcopenia, and osteoporosis. This new perspective leads us to propose that Pas function as novel biomarkers for age-related diseases, with the main purpose of achieving new molecular alternatives for healthier aging.


Assuntos
Poliaminas , Espermidina , Espermina/fisiologia , Putrescina
2.
Genes Immun ; 22(1): 24-34, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33531683

RESUMO

Sepsis is a life-threatening organ dysfunction condition caused by a dysregulated response to an infection that is common among patients with moderate to severe burn injury. Previously, genomic variants in Toll-like receptor 4 (TLR4), a key innate immunity receptor, have been associated with sepsis and infection susceptibility. In this study, the association of six TLR4 SNPs with sepsis after burn injury was tested in the Mexican mestizo population. We found that the rs2737190 polymorphism is associated with sepsis after burn trauma. Interestingly, the G allele and GG genotype were associated with a lower risk of developing sepsis. Since the rs2737190 SNP is in the promoter region of the TLR4 gene, we analyzed the possibility that this polymorphism regulates the TLR4 pathway. We cultured peripheral blood mononuclear cells from different genotype carriers and found, after stimulation with LPS, that carriers of the GG genotype showed a higher expression of TLR4, IL6, and TNFα than AA genotype carriers. The results suggest that the GG genotype produces an increase in the TLR4 expression, and therefore an improvement in the immune response. We conclude that the rs2737190 polymorphism may become a useful marker for genetic studies of sepsis in patients after a burn injury.


Assuntos
Queimaduras , Sepse , Queimaduras/complicações , Queimaduras/genética , Predisposição Genética para Doença , Genótipo , Humanos , Leucócitos Mononucleares , Polimorfismo de Nucleotídeo Único , Sepse/genética , Receptor 4 Toll-Like/genética
3.
Dermatol Ther ; 34(1): e14628, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33277959

RESUMO

Lamellar ichthyosis (LI) is a genetic skin disorder characterized by dark brown scales, palmoplantar hyperkeratosis, pain, and itching. LI severity could have implications in psychological aspects, causing depression and impairment in the quality of life (QoL) of patients. In this study, we used the Congenital Ichthyosis Severity Index, the Depression Beck Inventory-II (DBI-II), and the Dermatologic Life Quality Index (DLQI) to assess severity, level of depression, and impairment in QoL in a group of patients with LI. We observed that the majority of the patients presented a high severity level concerning the presence of scales (57.7%), while for erythema and alopecia, the severity was less 80% of the analyzed patients presented depression, while only 20.8% of individuals of the control group presented it (P < .001, OR = 15.2). While for QoL, only 4.3% of the patients did not exhibit any impairment. Finally, the increase in the score obtained in DBI-II was correlated with the DLQI score (rs = 0.663, P = .0014). Our results suggest that patients with LI have an increased risk of suffering depression and impairment in their QoL; thus, the management of their disease should be performed from a multidisciplinary perspective to improve the global aspects of their lives.


Assuntos
Ictiose Lamelar , Qualidade de Vida , Alopecia , Depressão/diagnóstico , Depressão/epidemiologia , Eritema , Humanos , Ictiose Lamelar/diagnóstico , Ictiose Lamelar/epidemiologia
4.
Cerebellum ; 19(3): 446-458, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32086717

RESUMO

Spinocerebellar ataxias (SCAs) comprise a heterogeneous group of autosomal dominant disorders. The relative frequency of the different SCA subtypes varies broadly among different geographical and ethnic groups as result of genetic drifts. This review aims to provide an update regarding SCA founders in the American continents and the Caribbean as well as to discuss characteristics of these populations. Clusters of SCAs were detected in Eastern regions of Cuba for SCA2, in South Brazil for SCA3/MJD, and in Southeast regions of Mexico for SCA7. Prevalence rates were obtained and reached 154 (municipality of Báguano, Cuba), 166 (General Câmara, Brazil), and 423 (Tlaltetela, Mexico) patients/100,000 for SCA2, SCA3/MJD, and SCA7, respectively. In contrast, the scattered families with spinocerebellar ataxia type 10 (SCA10) reported all over North and South Americas have been associated to a common Native American ancestry that may have risen in East Asia and migrated to Americas 10,000 to 20,000 years ago. The comprehensive review showed that for each of these SCAs corresponded at least the development of one study group with a large production of scientific evidence often generalizable to all carriers of these conditions. Clusters of SCA populations in the American continents and the Caribbean provide unusual opportunity to gain insights into clinical and genetic characteristics of these disorders. Furthermore, the presence of large populations of patients living close to study centers can favor the development of meaningful clinical trials, which will impact on therapies and on quality of life of SCA carriers worldwide.


Assuntos
Efeito Fundador , Ataxias Espinocerebelares/etnologia , Ataxias Espinocerebelares/genética , Ataxina-10/genética , Ataxina-2/genética , Ataxina-3/genética , Brasil/etnologia , Região do Caribe/etnologia , Cuba/etnologia , Humanos , México/etnologia , Proteínas Repressoras/genética , Ataxias Espinocerebelares/diagnóstico , Indígena Americano ou Nativo do Alasca/etnologia , Indígena Americano ou Nativo do Alasca/genética
5.
Cell Mol Biol (Noisy-le-grand) ; 66(4): 191-198, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32583795

RESUMO

Human skin possesses an essential function in the maintenance of individuals' health. However, it may undergo a variety of lesions that produce wounds of distinct severity. In this respect, instantly after any skin wound, the process of tissue regeneration and repair initiates. Nevertheless, diverse factors can delay this process, including bacterial infections, nutritional status, age, hypoxia, chronic diseases, necrosis, and vascular and arterial diseases. Thus, wound dressings are frequently used to improve wound healing. Those wound dressings are fabricated with diverse materials, which confer them different properties. In this regard, hyaluronic acid is a natural polysaccharide widely distributed in extracellular matrices of mammal tissues, which possesses remarkable attributes in terms of biocompatibility, biodegradability, and low cost. Moreover, hyaluronic acid exhibits several beneficial effects on wound healing, such as the decrease of inflammatory processes, regulation of tissue remodeling, and enhancement of angiogenesis. Therefore, in recent years, there is growing attention in this polysaccharide for the design and manufacture of novel wound dressings, which have shown encouraging properties. Here, we describe the different approaches of hyaluronic acid for the production of wound dressings, encompassing hydrogels, films, scaffolds, foams, topical formulations, and nanoformulations, as well as its beneficial effects on wound healing. Finally, we discuss perspectives about the use of hyaluronic acid in wound dressings.


Assuntos
Bandagens , Ácido Hialurônico/uso terapêutico , Ferimentos e Lesões/terapia , Animais , Preparações de Ação Retardada/farmacologia , Humanos , Ácido Hialurônico/química , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacos
6.
Neurodegener Dis ; 20(5-6): 185-192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34247167

RESUMO

BACKGROUND: Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant disorder caused by a mutation in the ATXN7 gene. The involvement of the brainstem auditory pathway in pathogenesis of this disease has not been systematically assessed. AIM: To determine involvement of the brainstem auditory pathway in SCA7 patients and its relationship to clinical features of the disease. METHODS: In this case-control study, brainstem auditory-evoked potentials (BAEPs) were assessed in 12 SCA7 patients with clinical and molecular diagnosis, compared to 2 control groups of 16 SCA2 patients and 16 healthy controls. RESULTS: SCA7 patients exhibited significant prolongation of I-wave and III-wave latencies, whereas SCA2 patients showed increased latencies for III and V waves and I-III interpeak interval. SCA7 patients with larger I-wave latencies exhibited larger CAG repeats, earlier onset age, and higher SARA scores, but in SCA2 cases, these were not observed. CONCLUSIONS: BAEP tests revealed functional involvement of the auditory pathway in SCA7 (mainly at) peripheral portions, which gave new insights into the disease physiopathology different from SCA2 and may unravel distinct pathoanatomical effects of polyQ expansions in the central nervous system. SIGNIFICANCE: These findings offer important insights into the distinctive disease mechanisms in SCA7 and SCA2, which could be useful for differential diagnosis and designing specific precision medicine approaches for both conditions.

7.
Cerebellum ; 18(3): 397-405, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30701400

RESUMO

Today, neurorehabilitation has become in a widely used therapeutic approach in spinocerebellar ataxias; however, there are scarce powerful clinical studies supporting this notion, and these studies require extension to other specific SCA subtypes in order to be able to form conclusions concerning its beneficial effects. Therefore, in this study, we perform for the first time a case-control pilot randomized, single-blinded, cross-sectional, and observational study to evaluate the effects of physical neurorehabilitation on the clinical and biochemical features of patients with spinocerebellar ataxia type 7 (SCA7) in 18 patients diagnosed with SCA7. In agreement with the exercise regimen, the participants were assigned to groups as follows: (a) the intensive training group, (b) the moderate training group, and (c) the non-training group (control group).We found that both moderate and intensive training groups showed a reduction in SARA scores but not INAS scores, compared with the control group (p < 0.05). Furthermore, trained patients exhibited improvement in the SARA sub-scores in stance, gait, dysarthria, dysmetria, and tremor, as compared with the control group (p < 0.05). No significant improvements were found in daily living activities, as revealed by Barthel and Lawton scales (p > 0.05). Patients under physical training exhibited significantly decreased levels in lipid-damage biomarkers and malondialdehyde, as well as a significant increase in the activity of the antioxidant enzyme PON-1, compared with the control group (p < 0.05). Physical exercise improved some cerebellar characteristics and the oxidative state of patients with SCA7, which suggest a beneficial effect on the general health condition of patients.


Assuntos
Modalidades de Fisioterapia , Ataxias Espinocerebelares/reabilitação , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
8.
Muscle Nerve ; 60(1): 90-95, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30994189

RESUMO

INTRODUCTION: Myotonic dystrophy type 1 (DM1) is a multisystemic disorder characterized mainly by skeletal muscle alterations. Although oropharyngeal dysphagia is a prominent clinical feature of DM1, it remains poorly studied in its early disease stages. METHODS: Dysphagia was investigated in 11 presymptomatic DM1 carriers, 14 patients with DM1 and 12 age-matched healthy controls, by using fiberoptic endoscopic evaluation of swallowing (FEES) and clinical scores. RESULTS: Scores for the FEES variables, delayed pharyngeal reflex, posterior pooling, and postswallow residue were significantly greater in patients with DM1 and in presymptomatic DM1 carriers than in healthy controls (P < 0.05); oropharyngeal dysfunction was more severe in patients than in presymptomatic carriers. Penetration/aspiration was found altered exclusively in patients with DM1 (P < 0.05). DISCUSSION: Swallowing dysfunction occurs in presymptomatic DM1 carriers. Timely diagnosis of dysphagia in preclinical stages of the disease will aid in the timely management of presymptomatic carriers, potentially preventing medical complications. Muscle Nerve, 2019.


Assuntos
Doenças Assintomáticas , Transtornos de Deglutição/fisiopatologia , Distrofia Miotônica/fisiopatologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Transtornos de Deglutição/etiologia , Endoscopia do Sistema Digestório , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Distrofia Miotônica/complicações , Distrofia Miotônica/genética , Miotonina Proteína Quinase/genética , Adulto Jovem
9.
Skin Res Technol ; 25(2): 187-193, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30302824

RESUMO

BACKGROUND: Previous studies analyzed a series of representative anatomical regions in the human body; however, there is a wide structural and cellular variability in the constitution of the skin. Our objective was to perform a comprehensive assessment of human skin hydration throughout the largest possible area. MATERIALS AND METHODS: Hydration was registered by Corneometer® CM825 probe in 23 anatomical regions of five healthy men. Each zone was analyzed by 2-cm segments in the supine, prone, and lateral positions. A total of 7863 measurements were registered. RESULTS: Differences in the degree of hydration among the prone, supine, and lateral regions were observed. The chest and back showed a pattern of increased hydration toward the neck area. Higher levels of hydration were evidenced in the proximal areas and in the regions near the elbow and knee. The regions of greater mechanical wear and with greater exposure to the sun exhibited a lower degree of hydration. CONCLUSION: The human skin exhibited hydration patterns influenced by anatomical function and the degree of sun exposure. Detailed information of the hydration patterns could serve as reference for the design of topical products, as an indicator of their effectiveness, and for the monitoring of skin pathologies.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Água Corporal/efeitos dos fármacos , Dermatopatias/tratamento farmacológico , Pele/citologia , Adulto , Água Corporal/metabolismo , Estudos Transversais , Corpo Humano , Humanos , Masculino , Estado de Hidratação do Organismo/fisiologia , Projetos Piloto , Pele/metabolismo , Dermatopatias/metabolismo , Fenômenos Fisiológicos da Pele
10.
Skin Res Technol ; 25(3): 375-381, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30600859

RESUMO

BACKGROUND: Reliable methods for the quantitative evaluation of skin of patients with ichthyosis are critically needed. Our purpose was to evaluate the biomechanical parameters of skin in a cohort of patients with clinically diagnosed lamellar ichthyosis. MATERIALS AND METHODS: Twenty-two patients diagnosed with lamellar ichthyosis were studied. Ichthyosis plaques located in upper distal limbs were assayed, and a nearby anatomical region without plaques from the same patient was employed as control. Skin biomechanical properties were studied through a non-invasive device (Cutometer® MPA 580). RESULTS: Ichthyosis plaques had higher values for the Uf-Ua parameter and lower values for the Ua/Uf, Ur/Ue, and Ur/Uf parameters. Adults and children showed similar statistical differences. There were no significant differences in data from men, whereas in women differences for all of the parameters were found. There was a significant decrease in the hydration and an increase in melanin index in the ichthyosis plaques. CONCLUSION: Our results suggest that analysis of parameters Uf-Ua, Ua/Uf, Ur/Ue, Ur/Uf, hydration, and melanin index could be employed for quantitative monitoring of skin. Therefore, the non-invasive method applied may be suitable for evaluation of skin of patients with ichthyosis in response to medical treatments.


Assuntos
Ictiose Lamelar/fisiopatologia , Fenômenos Fisiológicos da Pele , Pele/patologia , Adolescente , Adulto , Idoso , Fenômenos Biomecânicos/fisiologia , Criança , Pré-Escolar , Elasticidade , Feminino , Humanos , Ictiose Lamelar/patologia , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Cerebellum ; 17(5): 601-609, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29876803

RESUMO

Spinocerebellar ataxia type 7 is a neurodegenerative inherited disease caused by a CAG expansion in the coding region of the ATXN7 gene, which results in the synthesis of polyglutamine-containing ataxin-7. Expression of mutant ataxin-7 disturbs different cell processes, including transcriptional regulation, protein conformation and clearance, autophagy, and glutamate transport; however, mechanisms underlying neurodegeneration in SCA7 are still unknown. Implication of oxidative stress in the pathogenesis of various neurodegenerative diseases, including polyglutamine disorders, has recently emerged. We perform a cross-sectional study to determine for the first time pheripheral levels of different oxidative stress markers in 29 SCA7 patients and 28 age- and sex-matched healthy subjects. Patients with SCA7 exhibit oxidative damage to lipids (high levels of lipid hydroperoxides and malondialdehyde) and proteins (elevated levels of advanced oxidation protein products and protein carbonyls). Furthermore, SCA7 patients showed enhanced activity of various anti-oxidant enzymes (glutathione reductase, glutathione peroxidase, and paraoxonase) as well as increased total anti-oxidant capacity, which suggest that activation of the antioxidant defense system might occur to counteract oxidant damage. Strikingly, we found positive correlation between some altered oxidative stress markers and disease severity, as determined by different clinical scales, with early-onset patients showing a more severe disturbance of the redox system than adult-onset patients. In summay, our results suggest that oxidative stress might contribute to SCA7 pathogenesis. Furthermore, oxidative stress biomarkers that were found relevant to SCA7 in this study could be useful to follow disease progression and monitor therapeutic intervention.


Assuntos
Estresse Oxidativo , Ataxias Espinocerebelares/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
12.
Ann Hum Genet ; 81(5): 197-204, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28597910

RESUMO

Spinocerebellar ataxia type 7 (SCA7) is a rare neurogenetic disorder caused by highly unstable CAG repeat expansion mutation in coding region of SCA7. We aimed to understand the effect of diverse ATXN7 cis-element in correlation with CAG expansion mutation of SCA7. We initially performed an analysis to identify the haplotype background of CAG expanded alleles using eight bi-allelic single nucleotide polymorphisms (SNPs) flanking an ATXN7-CAG expansion in 32 individuals from nine unrelated Indian SCA7 families and 88 healthy controls. Subsequent validation of the findings was performed in 89 ATXN7-CAG mutation carriers and in 119 unrelated healthy controls of Mexican ancestry. The haplotype analyses showed a shared haplotype background and C allele of SNP rs6798742 (approximately 6 kb from the 3'-end of CAG repeats) is in complete association with expanded, premutation, intermediate, and the majority of large normal (≥12) CAG allele. The C allele (ancestral/chimp allele) association was validated in SCA7 subjects and healthy controls from Mexico, suggesting its substantial association with CAG expanded and expansion-prone chromosomes. Analysis of rs6798742 and other neighboring functional SNPs within 6 kb in experimental datasets (Encyclopedia of DNA Elements; ENCODE) shows functional marks that could affect transcription as well as histone methylation. An allelic association of the CAG region to an intronic SNP in two different ethnic and geographical populations suggests a -cis factor-dependent mechanism in ATXN7 CAG-region expansion.


Assuntos
Ataxina-7/genética , Expansão das Repetições de DNA , Polimorfismo de Nucleotídeo Único , Ataxias Espinocerebelares/genética , Estudos de Associação Genética , Haplótipos , Humanos , Índia , México
13.
Drug Dev Ind Pharm ; 43(6): 871-888, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28142290

RESUMO

Polyglutamine (polyQ) diseases are a class of neurodegenerative disorders that cause cellular dysfunction and, eventually, neuronal death in specific regions of the brain. Neurodegeneration is linked to the misfolding and aggregation of expanded polyQ-containing proteins, and their inhibition is one of major therapeutic strategies used commonly. However, successful treatment has been limited to date because of the intrinsic properties of therapeutic agents (poor water solubility, low bioavailability, poor pharmacokinetic properties), and difficulty in crossing physiological barriers, including the blood-brain barrier (BBB). In order to solve these problems, nanoparticulate systems with dimensions of 1-1000 nm able to incorporate small and macromolecules with therapeutic value, to protect and deliver them directly to the brain, have recently been developed, but their use for targeting polyQ disease-mediated protein misfolding and aggregation remains scarce. This review provides an update of the polyQ protein aggregation process and the development of therapeutic strategies for halting it. The main features that a nanoparticulate system should possess in order to enhance brain delivery are discussed, as well as the different types of materials utilized to produce them. The final part of this review focuses on the potential application of nanoparticulate system strategies to improve the specific and efficient delivery of therapeutic agents to the brain for the treatment of polyQ diseases.


Assuntos
Nanopartículas , Doenças Neurodegenerativas/tratamento farmacológico , Peptídeos , Animais , Barreira Hematoencefálica , Humanos
14.
Muscle Nerve ; 54(6): 1064-1071, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27104310

RESUMO

INTRODUCTION: In this study, we determined normal levels of dysferlin expression in CD14+ monocytes by flow cytometry (FC) as a screening tool for dysferlinopathies. METHODS: Monocytes from 183 healthy individuals and 29 patients were immunolabeled, run on an FACScalibur flow cytometer, and analyzed by FlowJo software. RESULTS: The relative quantity of dysferlin was expressed as mean fluorescence intensity (MFI). Performance of this diagnostic test was assessed by calculating likelihood ratios at different MFI cut-off points, which allowed definition of 4 disease classification groups in a simplified algorithm. CONCLUSION: The MFI value may differentiate patients with dysferlinopathy from healthy individuals; it may be a useful marker for screening purposes. Muscle Nerve 54: 1064-1071, 2016.


Assuntos
Proteínas de Membrana/metabolismo , Monócitos/metabolismo , Proteínas Musculares/metabolismo , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/patologia , Adulto , Algoritmos , Análise Mutacional de DNA , Disferlina , Feminino , Citometria de Fluxo , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Programas de Rastreamento , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação/genética , Estatísticas não Paramétricas , Adulto Jovem
15.
Neurobiol Dis ; 74: 336-46, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25517101

RESUMO

In striatonigral projections activation of dopamine D3 receptors (D3Rs) potentiates the stimulation of GABA release and cAMP production caused by activation of dopamine D1 receptors (D1Rs). Cytoplasmic [Ca(2+)] in the terminals controls this response by modulating CaMKII, an enzyme that depresses D3R action. To examine the effects of dopamine deprivation on D3R signaling we investigated their function in striatonigral terminals of hemiparkinsonian rats. Denervation switched the signaling cascade initiated by D3R activation. In the non-lesioned side activation of D3R potentiated the stimulatory effects of D1R activation on cAMP production and K(+)-depolarization induced [(3)H] GABA release. In contrast, in the denervated side the stimulatory effects of both D1R activation and forskolin administration were blocked by D3R activation. In non-lesioned slices, D3R responses were inhibited by the activation of CaMKII produced by K(+)-depolarization (via increased Ca(2+) entry). The CaMKII-induced inhibition was blocked by the selective inhibitor KN-62. In denervated tissues the response to D3R stimulation was not modified either by K(+) depolarization or by blocking CaMKII with KN-62. Immunoblotting studies showed that depolarization-induced CaMKII binding to the D3 receptor and CaMKII phosphorylation were suppressed in denervated tissues. We also determined calmodulin expression with PCR and immunoblot techniques. Both techniques showed that calmodulin expression was depressed in the lesioned side. In sum, our studies show that dopaminergic denervation switches the D3R signaling cascade and depresses CaMKII signaling through a process that appears to involve reduced calmodulin levels. Since calmodulin is a major cytoplasmic Ca(2+) buffer our findings suggest that abnormal Ca(2+) buffering may be an important component of the abnormalities observed during dopaminergic denervation.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Calmodulina/metabolismo , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Receptores de Dopamina D3/metabolismo , Substância Negra/metabolismo , Animais , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Corpo Estriado/efeitos dos fármacos , AMP Cíclico/metabolismo , Fosfatos de Dinucleosídeos/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Masculino , Feixe Prosencefálico Mediano/fisiopatologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Oxidopamina , Fosforilação/efeitos dos fármacos , Ratos Wistar , Transdução de Sinais , Substância Negra/efeitos dos fármacos , Técnicas de Cultura de Tecidos , Ácido gama-Aminobutírico/metabolismo
16.
Eur Neurol ; 73(3-4): 173-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25614072

RESUMO

BACKGROUND: Autosomal dominant spinocerebellar ataxias (SCA) are a group of inherited neurodegenerative disorders that typically show peripheral neuropathy. SCA7 is one of the rarest forms of SCA (<1/100,000 individuals). However, the disease shows a prevalence of ∼800/100,000 inhabitants in certain regions of Mexico. This low global prevalence may explain, at least in part, the isolated anecdotal and limited clinical data regarding peripheral neuropathy in SCA7 patients. AIM: To assess sensory and motor peripheral nerve action potentials in an SCA7 patients group and in healthy volunteers, and subsequently correlate the electrophysiological findings with clinical and genetic features. MATERIALS AND METHODS: We enrolled in our study, 13 symptomatic SCA7 patients with a confirmed molecular and clinical diagnosis, and 19 healthy volunteers as the control group. Nerve conduction studies were carried out using standard electromyography recording methods. The sensory and motor latency, amplitude and conduction velocity were recorded in both experimental groups and analyzed using the Student's t-test. RESULTS: SCA7 patients showed a significant prolongation of sensory nerve conduction latencies, as well as a decrease in sensory amplitudes. Decreases in motor amplitudes and peroneal conduction velocity were also observed. Finally, we found an association between CAG repeats and the severity of cerebellar and non-cerebellar symptoms with electrophysiological signs of demyelinization. DISCUSSION: Our results reveal the existence of a critical sensorimotor peripheral neuropathy in SCA7 patients. Moreover, we show that using sensitive electrophysiological tools to evaluate nerve conduction can improve the diagnosis and design of therapeutic options based on pharmacological and rehabilitative strategies. CONCLUSION: These findings demonstrate that SCA7 is a disease that globally affects the peripheral nervous system.


Assuntos
Doenças do Sistema Nervoso Periférico/genética , Ataxias Espinocerebelares/complicações , Adolescente , Adulto , Idoso , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/fisiopatologia
17.
Cerebellum ; 13(2): 215-21, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24097205

RESUMO

Hereditary ataxias are a heterogeneous group of neurological diseases characterized by progressive cerebellar syndrome and numerous other features, which result in great diversity of ataxia subtypes. Despite the characterization of a number of both autosomal dominant and autosomal recessive ataxias, it is thought that a large group of these conditions remains to be identified. In this study, we report the characterization of five patients (three Mexicans and two Italians) who exhibit a peculiar form of recessive ataxia associated with coughing. The main clinical and neurophysiological features of these patients include cerebellar ataxia, paroxysmal cough, restless legs syndrome (RLS), choreic movements, atrophy of distal muscles, and oculomotor disorders. Brain magnetic resonance imaging (MRI) revealed cerebellar atrophy, while video polysomnography (VPSG) studies showed a severe pattern of breathing-related sleep disorder, including sleep apnea, snoring, and significant oxygen saturation in the absence of risk factors. All patients share clinical features in the peripheral nervous system, including reduction of amplitude and prolonged latency of sensory potentials in median and sural nerves. Altogether, clinical criteria as well as molecular genetic testing that was negative for different autosomal dominant and autosomal recessive ataxias suggest the presence of a new form of recessive ataxia. This ataxia, in which cerebellar signs are preceded by paroxysmal cough, affects not only the cerebellum and its fiber connections, but also the sensory peripheral nervous system and extracerebellar central pathways.


Assuntos
Tosse/complicações , Ataxias Espinocerebelares/complicações , Idoso , Atrofia , Encéfalo/patologia , Tosse/genética , Tosse/patologia , Tosse/fisiopatologia , Feminino , Testes Genéticos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Polissonografia , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Síndrome
18.
Hum Biol ; 86(4): 289-312, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25959695

RESUMO

This study aims to portray the complex diversity of the Mexican Mestizo population, which represents 98.8% of the entire population of Mexico. We compiled extended haplotype data of the Y chromosome from populations in the Central Valley of Mexico (CVM), which we compared with other Mestizo and parental (Amerindian, European, and African) populations. A complex ancestral relationship was found in the CVM population, suggesting cosmopolitan origins. Nevertheless, the most preeminent lineages point toward a European ancestry, where the R1b lineage was most frequent. In addition, important frequencies of Amerindian lineages were also found in the Mestizo sample studied. Interestingly, the Amerindian ancestry showed a remarkable substructure, which was represented by the two main founding lineages: QL54 (× M3) and M3. However, even within each lineage a high diversity was found despite the small number of sample bearers of these lineages. Further, we detected important genetic differences between the CVM populations and the Mexican Mestizo populations from the north and south. This result points to the fact that Mestizo populations present different ancestral proportions, which are related to the demographic events that gave origin to each population. Finally, we provide additional forensic statistical parameters that are useful in the interpretation of genetic analysis where autosomal loci are limited. Our findings illustrate the complex genetic background of the Mexican Mestizo population and reinforce the need to encompass more geographic regions to generate more robust data for forensic applications.


Assuntos
Cromossomos Humanos Y/genética , Indígenas Norte-Americanos/genética , Filogenia , População Negra , Frequência do Gene , Variação Genética/genética , Genética Populacional , Haplótipos/genética , Humanos , México/epidemiologia , População Branca
19.
Carbohydr Polym ; 336: 122121, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670753

RESUMO

This study aimed to modify chitosan (CS) by gamma irradiation and use it as a surface coating of nanoparticles (NPs) fabricated of poly lactic-co-glycolic acid (PLGA) to create mostly biocompatible nanosystems that can transport drugs to neurons. Gamma irradiation produced irradiated CS (CSγ) with a very low molecular weight (15.2-19.2 kDa). Coating NPs-PLGA with CSγ caused significant changes in their Z potential, making it slightly positive (from -21.7 ± 2.8 mV to +7.1 ± 2.3 mV) and in their particle size (184.4 0.4 ± 7.9 nm to 211.9 ± 14.04 nm). However, these changes were more pronounced in NPs coated with non-irradiated CS (Z potential = +54.0 ± 1.43 mV, size = 348.1 ± 16.44 nm). NPs coated with CSγ presented lower cytotoxicity and similar internalization levels in SH-SY5Y neuronal cells than NPs coated with non-irradiated CS, suggesting higher biocompatibility. Highly biocompatible NPs are desirable as nanocarriers to deliver drugs to the brain, as they help maintain the structure and function of the blood-brain barrier. Therefore, the NPs developed in this study could be evaluated as drug-delivery systems for treating brain diseases.


Assuntos
Quitosana , Nanopartículas , Neurônios , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Quitosana/química , Humanos , Nanopartículas/química , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Portadores de Fármacos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Tamanho da Partícula , Raios gama
20.
Mol Biol Rep ; 40(7): 4275-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23677709

RESUMO

Abnormal methylation is related to cancer development. Since DNMT3B is an enzyme that modulates genomic methylation, we hypothesized that genetic variants of the promoter DNMT3B may be associated with an increased risk of developing cervical cancer. Our aim was to investigate the association between -579GT and 46359CT polymorphisms of DNMT3B and cervical cancer, high-grade squamous intraepithelial lesions (HSIL), and low-grade squamous intraepithelial lesions (LSIL). Samples from 200 healthy women and 130 women with squamous intraepithelial lesions (70 with cervical cancer, 30 with HSIL, and 30 with LSIL) were analyzed. Polymorphism genotyping was performed using PCR and restriction fragment length polymorphism. The -579GT polymorphism was not associated with cervical cancer, HSIL, or LSIL. The CT genotype of 46359CT polymorphism was significantly associated with cervical cancer risk (OR 8.75, CI 1.27-374.1), whereas the TT genotype was associated with a significantly decreased risk of HSIL (OR 0.66, CI 0.01-0.32) and LSIL (OR 0.11, CI 0.026-0.45). Our results suggest that genotyping the 46359CT polymorphism in DNMT3B may help identify women who are genetically susceptible to cervical cancer development. Additional studies with larger sample sizes are necessary to confirm our findings.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patologia , Polimorfismo Genético , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Adolescente , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias de Células Escamosas/virologia , Risco , Neoplasias do Colo do Útero/virologia , Adulto Jovem , Displasia do Colo do Útero/genética , DNA Metiltransferase 3B
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