RESUMO
RESUMO A neuropatia óptica hereditária de Leber é uma doença mitocondrial hereditária neurodegenerativa. A taxa potencial de recuperação espontânea é controversa na literatura. A terapia genética tem sido estudada como suporte aos pacientes. O objetivo desta revisão foi avaliar qualitativamente a segurança, os efeitos adversos e a eficácia da terapia gênica disponível. Trata-se de uma revisão sistemática de artigos indexados nas bases de dados PubMed®, Biblioteca Virtual em Saúde, SciELO, Cochrane, ScienceDirect, Scopus e Lilacs no primeiro semestre de 2021. Os critérios de inclusão e filtros foram: artigos relacionados ao tema, estudos randomizados, ensaios clínicos, trabalhos em humanos, últimos 5 anos, nas línguas portuguesa, inglesa e espanhola e texto completo disponível gratuitamente. Os parâmetros de exclusão foram: artigos duplicados, fuga ao tema, artigos de revisão, trabalhos não disponíveis e que fugiam aos critérios de inclusão. O coeficiente de kappa foi 0,812. A terapia não apresentou efeitos adversos sérios em nenhum dos artigos selecionados, e os efeitos menores sofreram 100% de remissão espontânea após o tratamento. Apesar de NAbs terem sido encontrados no soro de alguns pacientes, não houve associação entre a resposta imune adaptativa e a injeção do vetor viral. O tratamento foi eficaz na melhora da acuidade e campo visual. Vários estudos confirmaram a eficácia da terapia gênica, em doses baixas e médias, na melhora da acuidade visual e também sobre os efeitos adversos comuns relacionados à altas doses. A resposta imune humoral e a variação dos NAbs no soro foi citada em mais de um artigo. A terapia foi eficaz na melhora da acuidade visual e os efeitos adversos que surgiram foram tratados facilmente. No entanto, a resposta imune humoral ainda precisa ser estudada.
ABSTRACT Leber's Hereditary Optic Neuropathy (LHON) is an inherited neurodegenerative mitochondrial disease. The potential rate of spontaneous recovery is controversial in the literature. Gene therapy has been studied to support patients. The objective of this review was to qualitatively assess the safety, adverse effects, and efficacy of available gene therapy. This is a systematic review of articles indexed in PubMed®, VHL, SciELO, Cochrane, ScienceDirect, Scopus, and Lilacs databases, in the first half of 2021. Inclusion criteria and filters were: articles related to the topic, randomized studies, clinical trials, work in humans, last 5 years, in Portuguese, English, and Spanish and full text available for free. The exclusion parameters were: duplicate articles, not related to the topic, review articles, not available works, and works that did not meet the inclusion criteria. The kappa coefficient was 0.812. The therapy had no serious adverse effects in any of the selected articles, and minor effects experienced 100% spontaneous remission after treatment. Although NAbs were found in the serum of some patients, there was no association between the adaptive immune response and the injection of the viral vector. The treatment was effective in improving acuity and visual field. Several studies have confirmed the effectiveness of gene therapy, at low and medium doses, in improving visual acuity and also on common adverse effects related to high doses. The humoral immune response and the variation in serum NAbs was cited in more than one article. The therapy was effective in improving visual acuity and the adverse effects that arose were easily treated. However, the humoral immune response still needs to be studied.
Assuntos
Humanos , Terapia Genética/métodos , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/terapia , Terapia Genética/efeitos adversos , Adenoviridae , Resultado do Tratamento , Injeções Intravítreas , NADH Desidrogenase/genética , NADH Desidrogenase/uso terapêuticoRESUMO
We sequenced maxicircles from T. cruzi strains representative of the species evolutionary diversity by using long-read sequencing, which allowed us to uncollapse their repetitive regions, finding that their real lengths range from 35 to 50 kb. T. cruzi maxicircles have a common architecture composed of four regions: coding region (CR), AT-rich region, short (SR) and long repeats (LR). Distribution of genes, both in order and in strand orientation are conserved, being the main differences the presence of deletions affecting genes coding for NADH dehydrogenase subunits, reinforcing biochemical findings that indicate that complex I is not functional in T. cruzi. Moreover, the presence of complete minicircles into maxicircles of some strains lead us to think about the origin of minicircles. Finally, a careful phylogenetic analysis was conducted using coding regions of maxicircles from up to 29 strains, and 1108 single copy nuclear genes from all of the DTUs, clearly establishing that taxonomically T. cruzi is a complex of species composed by group 1 that contains clades A (TcI), B (TcIII) and D (TcIV), and group 2 (1 and 2 do not coincide with groups I and II described decades ago) containing clade C (TcII), being all hybrid strains of the BC type. Three variants of maxicircles exist in T. cruzi: a, b and c, in correspondence with clades A, B, and C from mitochondrial phylogenies. While A and C carry maxicircles a and c respectively, both clades B and D carry b maxicircle variant; hybrid strains also carry the b- variant. We then propose a new nomenclature that is self-descriptive and makes use of both the phylogenetic relationships and the maxicircle variants present in T. cruzi.
Assuntos
Evolução Molecular , Trypanosoma cruzi/genética , Doença de Chagas/parasitologia , Variação Genética , Genoma de Protozoário , Humanos , NADH Desidrogenase/genética , Filogenia , Proteínas de Protozoários/genética , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
Hesperidin is a flavonoid glycoside that is frequently found in citrus fruits. Our group have demonstrated that hesperidin has neuroprotective effect in 6-hydroxydopamine (6-OHDA) model of Parkinson's disease (PD), mainly by antioxidant mechanisms. Although the pathophysiology of PD remains uncertain, a large body of evidence has demonstrated that mitochondrial dysfunction and apoptosis play a critical role in dopaminergic nigrostriatal degeneration. However, the ability of hesperidin in modulating these mechanisms has not yet been investigated. In the present study, we examined the potential of a 28-day hesperidin treatment (50 mg/kg/day, p.o.) in preventing behavioral alterations induced by 6-OHDA injection via regulating mitochondrial dysfunction, apoptosis and dopaminergic neurons in the substantia nigra pars compacta (SNpc) in C57BL/6 mice. Our results demonstrated that hesperidin treatment improved motor, olfactory and spatial memory impairments elicited by 6-OHDA injection. Moreover, hesperidin treatment attenuated the loss of dopaminergic neurons (TH+ cells) in the SNpc and the depletion of dopamine (DA) and its metabolities 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum of 6-OHDA-lesioned mice. Hesperidin also protected against the inhibition of mitochondrial respiratory chain complex-I, -IV and V, the decrease of Na + -K + -ATPase activity and the increase of caspase-3 and -9 activity in the striatum. Taken together, our findings indicate that hesperidin mitigates the degeneration of dopaminergic neurons in the SNpc by preventing mitochondrial dysfunction and modulating apoptotic pathways in the striatum of 6-OHDA-treated mice, thus improving behavioral alterations. These results provide new insights on neuroprotective mechanisms of hesperidin in a relevant preclinical model of PD.
Assuntos
Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Hesperidina/farmacologia , Mitocôndrias/efeitos dos fármacos , Doença de Parkinson Secundária/patologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Aprendizagem por Discriminação/efeitos dos fármacos , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Atividade Motora/efeitos dos fármacos , NADH Desidrogenase/metabolismo , Oxidopamina , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
We report 24 new records of the Brazilian cownose ray Rhinoptera brasiliensis outside its accepted geographic range. Sequencing of a 442-base pair portion of the mitochondrial NADH dehydrogenase subunit 2 gene for 282 Rhinoptera samples revealed eight records off the east coast of the USA and 16 from the eastern Gulf of Mexico. Both sexes of all life stages were documented in all seasons over multiple years in the Indian River and Lake Worth lagoons, Florida, indicating that their range extends further in the western North Atlantic than previously described.
Assuntos
Distribuição Animal , NADH Desidrogenase/genética , Rajidae/genética , Animais , Oceano Atlântico , Feminino , Florida , Golfo do México , Masculino , Rios , Rajidae/classificaçãoRESUMO
Sea turtles are the only extant chelonian representatives that inhabit the marine environment. One key to successful colonization of this habitat is the adaptation to different energetic demands. Such energetic requirement is intrinsically related to the mitochondrial ability to generate energy through oxidative phosphorylation (OXPHOS) process. Here, we estimated Testudines phylogenetic relationships from 90 complete chelonian mitochondrial genomes and tested the adaptive evolution of 13 mitochondrial protein-coding genes of sea turtles to determine how natural selection shaped mitochondrial genes of the Chelonioidea clade. Complete mitogenomes showed strong support and resolution, differing at the position of the Chelonioidea clade in comparison to the turtle phylogeny based on nuclear genomic data. Codon models retrieved a relatively increased dN/dS (ω) on three OXPHOS genes for sea turtle lineages. Also, we found evidence of positive selection on at least three codon positions, encoded by NADH dehydrogenase genes (ND4 and ND5). The accelerated evolutionary rates found for sea turtles on COX2, ND1 and CYTB and the molecular footprints of positive selection found on ND4 and ND5 genes may be related to mitochondrial molecular adaptation to stress likely resulted from a more active lifestyle in sea turtles. Our study provides insight into the adaptive evolution of the mtDNA genome in sea turtles and its implications for the molecular mechanism of oxidative phosphorylation.
Assuntos
DNA Mitocondrial/genética , Ecossistema , Evolução Molecular , Genoma Mitocondrial/genética , Proteínas Mitocondriais/genética , Oceanos e Mares , Filogenia , Seleção Genética/genética , Tartarugas/genética , Adaptação Fisiológica/genética , Animais , Códon/genética , Ciclo-Oxigenase 2 , Metabolismo Energético/genética , NADH Desidrogenase/genética , Fosforilação OxidativaRESUMO
The genetic diversity of Neotropical deer is increasingly jeopardized, owing to declining population size. Thus, the formation of cryobanking of somatic cells is important for the preservation of these species using cloning. The transformation of these cells into viable embryos has been hampered by a lack of endangered species oocytes. Accordingly, the aim of this study was to produce brown brocket deer embryos by interspecific somatic cell nuclear transfer (iSCNT), using goat or cattle oocytes as cytoplasts, and to elucidate embryo mitochondrial activity by measuring the expression levels of ATP6, COX3, and ND5. Cattle embryos produced by in vitro fertilization (IVF) were used as a control. There were no differences in the development of embryos produced by traditional SCNT and iSCNT when using either the goat cytoplasts (38.4% vs. 25.0% cleaved and 40.0% vs. 50.0% morula rates, respectively) or cattle cytoplast (72.8% vs. 65.5% cleaved and 11.3% vs. 5.9% blastocyst rates, respectively). Concerning the gene expression, no significant difference was observed when goat oocytes were used as cytoplasts. However, when using cattle oocytes and 16S as a reference gene, the iSCNT upregulated COX3, when compared with SCNT group. In contrast, when GAPDH was used as a reference gene, all the evaluated genes were upregulated in the iSCNT group, when compared with the IVF group. When compared with the SCNT group, only the expression of ATP6 was statistically different. In conclusion, it was demonstrated that interspecific nuclear transfer is a potentially useful tool for conservation programs of endangered similar deer species.
Assuntos
Cervos/embriologia , Cervos/genética , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Genes Mitocondriais , Animais , Blastocisto/metabolismo , Bovinos , Células Cultivadas , Clonagem de Organismos/veterinária , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Embrião de Mamíferos/metabolismo , Feminino , Fertilização in vitro , Cabras , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Mórula/metabolismo , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Técnicas de Transferência Nuclear/veterinária , Oócitos/metabolismo , Regulação para CimaRESUMO
The Arabidopsis genome encodes >450 proteins containing the pentatricopeptide repeat (PPR) motif. The PPR proteins are classified into two groups, termed as P and P Long-Short (PLS) classes. Typically, the PLS subclass proteins are mainly involved in the RNA editing of mitochondrial and chloroplast transcripts, whereas most of the analyzed P subclass proteins have been mainly implicated in RNA metabolism, such as 5' or 3' transcript stabilization and processing, splicing and translation. Mutations of PPR genes often result in embryogenesis and altered seedling developmental defect phenotypes, but only a limited number of ppr mutants have been characterized in detail. In this report, we show that null mutations in the EMB2794 gene result in embryo arrest, due to altered splicing of nad2 transcripts in the Arabidopsis mitochondria. In angiosperms, nad2 has five exons that are transcribed individually from two mitochondrial DNA regions. Biochemical and in vivo analyses further indicate that recombinant or transgenic EMB2794 proteins bind to the nad2 pre-mRNAs in vitro as well as in vivo, suggesting a role for this protein in trans-splicing of nad2 intron 2 and possibly in the stability of the second pre-mRNA of nad2. Homozygous emb2794 lines, showing embryo-defective phenotypes, can be partially rescued by the addition of sucrose to the growth medium. Mitochondria of rescued homozygous mutant plants contain only traces of respiratory complex I, which lack the NADH-dehydrogenase activity.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Proteínas Mitocondriais/metabolismo , NADH Desidrogenase/metabolismo , RNA Mensageiro/metabolismo , Arabidopsis/enzimologia , Perfilação da Expressão Gênica , Potencial da Membrana Mitocondrial , Mutação , Reação em Cadeia da Polimerase em Tempo Real , Sementes/metabolismo , TranscriptomaRESUMO
Varroa destructor, a parasitic mite of the western honey bee, Apis mellifera L., is a serious threat to colonies and beekeeping worldwide. Population genetics studies of the mite have provided information on two mitochondrial haplotypes infecting honey bee colonies, named K and J (after Korea and Japan, respectively, where they were originally identified). On the American continent, the K haplotype is much more prevalent, with the J haplotype only detected in some areas of Brazil. The aims of the present study were to assess the genetic diversity of V. destructor populations in the major beekeeping region of Argentina and to evaluate the presence of heteroplasmy at the nucleotide level. Phoretic mites were collected from managed A. mellifera colonies in ten localities, and four mitochondrial DNA (mtDNA) regions (COXI, ND4, ND4L, and ND5) were analyzed. Based on cytochrome oxidase subunit I (COXI) sequencing, exclusively the K haplotype of V. destructor was detected. Furthermore, two sub-haplotypes (KArg-N1 and KArg-N2) were identified from a variation in ND4 sequences and the frequency of these sub-haplotypes was found to significantly correlate with geographical latitude. The occurrence of site heteroplasmy was also evident for this gene. Therefore, ND4 appears to be a sensitive marker for detecting genetic variability in mite populations. Site heteroplasmy emerges as a phenomenon that could be relatively frequent in V. destructor.
Assuntos
Abelhas/parasitologia , DNA Mitocondrial/genética , Variação Genética/genética , Proteínas Mitocondriais/genética , Varroidae/genética , Animais , Argentina , Criação de Abelhas , Brasil , Complexo I de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Haplótipos , Japão , NADH Desidrogenase/genética , República da CoreiaRESUMO
This study reports complete plastome sequences for six species of Neotropical Cranichideae and focuses on identification of the most variable regions (hotspots) in this group of orchids. These structure of these six plastomes is relatively conserved, exhibiting lengths ranging between 142,599 to 154,562 bp with 36.7% GC on average and exhibiting typical quadripartite arrangement (LSC, SSC and two IRs). Variation detected in the LSC/IR and SSC/IR junctions is explained by the loss of ndhF and ycf1 length variation. For the two genera of epiphytic clade in Spiranthinae, almost whole sets of the ndh-gene family were missing. Eight mutation hotspots were identified based on nucleotide diversity, sequence variability and parsimony-informative sites. Three of them (rps16-trnQ, trnT-trnL, rpl32-trnL) seem to be universal hotspots in the family, and the other five (trnG-trnR, trnR-atpA, trnP-psaJ, rpl32-infA, and rps15-ycf1) are described for the first time as orchid molecular hotspots. These regions have much more variation than all those used previously in phylogenetics of the group and offer useful plastid markers for phylogenetic, barcoding and population genetic studies. The use of whole plastomes or exclusive no-gap matrices also positioned with high support the holomycotrophic Rhizanthella among Orchidoideae plastomes in model-based analyses, showing the utility of plastomes for phylogenetic placement of this unusual genus.
Assuntos
Regulação da Expressão Gênica de Plantas , Variação Genética , Genoma , Orchidaceae/genética , Filogenia , Plastídeos/genética , Composição de Bases , Brasil , Mapeamento Cromossômico , Código de Barras de DNA Taxonômico/métodos , Ontologia Genética , Anotação de Sequência Molecular , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Orchidaceae/classificação , Orchidaceae/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Fasciola hepatica is a trematode parasite that affects mammals, including humans. In Brazil, fascioliasis, a disease caused by the parasite, is of great importance. The disorder affects the welfare of the Brazilian population through impairing the agricultural production of cattle, where the disease causes weight loss as a result of liver damage. This study aimed to evaluate the genetic diversity of F. hepatica throughout Southern Brazil to determine its geographic origin and estimate the colonization route of the parasite. To accomplish these aims, flukes were collected from slaughterhouses in three endemic areas of Rio Grande do Sul and Paraná states. DNA was isolated using the phenol-chloroform protocol from single flukes and two mitochondrial genes, cytochrome oxidase subunit I (COI) and nicotinamide dehydrogenase subunit 1 (Nad1), were amplified and sequenced. Ten haplotypes of COI were found from 75 isolated parasites and the total haplotype and nucleotide diversity observed were 0.475 and 0.002, respectively. Using the Nad1 gene, we found 24 haplotypes from 79 samples, resulting in haplotype and nucleotide diversity values of 0.756 and 0.004, respectively. An analysis of molecular variance showed that 57.4% and 77.5% of variation was within populations (FST), while 9.0 and 36.8% of variation was among groups (FCT) when considering COI and Nad1 genes, respectively. For COI, the fixation index values of 0.425 and 0.368 were obtained for FST and FCT, respectively, while analysis of Nad1 0.225 and 0.089 index values were obtained for FST and FCT, respectively. We have determined that F. hepatica found in the two distinct areas originated from several geographical regions, since we found haplotypes that were shared with at least three different continents. These data are in accordance with the recent colonization of Brazil, and the recent import of cattle from South American, European and, possibly, some African countries. The observed FST and FCT values for COI and Nad1 genes of F. hepatica may be a result of limited movement of animals within states and support the lack of geographical structure of the parasite in Brazil, which are in agreement with the observed cattle production systems in this region.