RESUMO
It is known that iron transporter proteins and their regulation can modulate the fish's immune system, suggesting these proteins as a potential candidate for fish vaccines. Previous studies have evidenced the effects of Atlantic salmon immunized with the chimeric iron-related protein named IPath® against bacterial and ectoparasitic infections. The present study aimed to explore the transcriptome modulation and the morphology of the sea louse Caligus rogercresseyi in response to Atlantic salmon injected with IPath®. Herein, Atlantic salmon were injected with IPath® and challenged to sea lice in controlled laboratory conditions. Then, female adults were collected after 25 days post-infection for molecular and morphological evaluation. Transcriptome analysis conducted in lice collected from immunized fish revealed high modulation of transcripts compared with the control groups. Notably, the low number of up/downregulated transcripts was mainly found in lice exposed to the IPath® fish group. Among the top-25 differentially expressed genes, Vitellogenin, Cytochrome oxidases, and proteases genes were strongly downregulated, suggesting that IPath® can alter lipid transport, hydrogen ion transmembrane transport, and proteolysis. The morphological analysis in lice collected from IPath® fish revealed abnormal embryogenesis and inflammatory processes of the genital segment. Furthermore, head kidney, spleen, and skin were also analyzed in immunized fish to evaluate the transcription expression of immune and iron homeostasis-related genes. The results showed downregulation of TLR22, MCHII, IL-1ß, ALAs, HO, BLVr, GSHPx, and Ferritin genes in head kidney and skin tissues; meanwhile, those genes did not show significant differences in spleen tissue. Overall, our findings suggest that IPath® can be used to enhance the fish immune response, showing a promissory commercial application against lice infections.
Assuntos
Copépodes/genética , Ectoparasitoses/prevenção & controle , Doenças dos Peixes/prevenção & controle , Proteínas Recombinantes/administração & dosagem , Salmo salar/parasitologia , Transcriptoma , Vacinas/administração & dosagem , Animais , Ectoparasitoses/veterinária , Feminino , Ferritinas/genética , Salmo salar/imunologia , Transferrina/genética , VacinaçãoRESUMO
Idiopathic varicocele is closely associated with male infertility or subfertility. Sertoli cell is a very important regulator of spermatogenesis. We investigated the morphofunctional alterations in the Sertoli cell and its possible involvement in the establishment of testicular primary lesion in experimental left-sided varicocele, induced from peripuberty. Twenty-five male peripubertal rats (44 days postpartum [dpp]) were distributed into two groups: control (C) and varicocele (V). Experimental left varicocele was induced in rats through the partial ligature of the left renal vein. Euthanasia was performed at 100 dpp. Testicular histopathology and testosterone plasmatic level were evaluated. Transferrin and vimentin proteins were, respectively, used as immunomarkers of Sertoli cell function and structure. Significant reductions in vimentin and transferrin expressions were noticed in androgen-dependent stages (VII and VIII) of the seminiferous epithelium cycle in V rats; testosterone plasmatic level was also reduced. Bilateral testicular histopathological alterations were found in V rats, mainly massive germ cell desquamation. The histological damage and changes in protein expressions occurred bilaterally. The relevant impairment of the functional and structural characteristics of the Sertoli cell, together with the typical massive germ cell desquamation, indicates that Sertoli cell changes can primarily contribute to the significant testicular dysfunction associated with varicocele.
Assuntos
Infertilidade Masculina/etiologia , Células de Sertoli/metabolismo , Espermatogênese/efeitos dos fármacos , Varicocele/etiologia , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Células Germinativas/metabolismo , Heparina/farmacologia , Ligadura , Masculino , Prognóstico , Ratos , Ratos Wistar , Veias Renais/metabolismo , Testículo/metabolismo , Testosterona/farmacologia , Transferrina/genética , Transferrina/metabolismo , Vimentina/genética , Vimentina/metabolismoRESUMO
Thyroid hormones (THs) and transferrin (Tf) are factors capable of favoring myelination due to their positive effects on oligodendroglial cell (OLG) differentiation. The first notion of a combined effect of apotransferrin (aTf) and TH emerged from experiments conducted in young hyperthyroid animals, which showed a seven-fold increase in the expression of Tf mRNA and precocious myelination when compared with control animals. The mechanism underlying this phenomenon in young hyperthyroid rats could consist of an increase in Tf synthesis, which in the CNS is almost exclusively produced by OLG. Overall, our results show that, during the initial stages of OLG differentiation, Tf synthesis triggers thyroid hormone receptor alpha 1 (TRα1) expression in the subventricular zone (SVZ) and promotes proliferating cells to become responsive to this trophic factor. Exposure to TH could then regulate Tf expression through TRα1 and promote the induction of thyroid hormone receptor beta (TRß) expression, which mediates TH effects on myelination through the activation of final OLG differentiation. This regulation of the combined effects of Tf and THs implies that both factors are fundamental actors during oligodendrogenesis. GLIA 2016;64:1879-1891.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Oligodendroglia/fisiologia , Transferrina/metabolismo , Transferrina/farmacologia , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Ventrículos Laterais/citologia , Proteína Básica da Mielina/metabolismo , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Wistar , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Células-Tronco/efeitos dos fármacos , Hormônios Tireóideos , Transferrina/genéticaRESUMO
Iron deficiency affects thousands of people worldwide. Biofortification of staple food crops aims to support the reduction of this deficiency. This study evaluates the effect of combinations of common beans and rice, targets for biofortification, with high carotenoid content crops on the iron bioavailability, protein gene expression, and antioxidant effect. Iron bioavailability was measured by the depletion/repletion method. Seven groups were tested (n = 7): Pontal bean (PB); rice + Pontal bean (R + BP); Pontal bean + sweet potato (PB + SP); Pontal bean + pumpkin (PB + P); Pontal bean + rice + sweet potato (PB + R + P); Pontal bean + rice + sweet potato (PB + R + SP); positive control (Ferrous Sulfate). The evaluations included: hemoglobin gain, hemoglobin regeneration efficiency (HRE), gene expression of divalente metal transporter 1 (DMT-1), duodenal citocromo B (DcytB), ferroportin, hephaestin, transferrin and ferritin and total plasma antioxidant capacity (TAC). The test groups, except the PB, showed higher HRE (p < 0.05) than the control. Gene expression of DMT-1, DcytB and ferroportin increased (p < 0.05) in the groups fed with high content carotenoid crops (sweet potato or pumpkin). The PB group presented lower (p < 0.05) TAC than the other groups. The combination of rice and common beans, and those with high carotenoid content crops increased protein gene expression, increasing the iron bioavailability and antioxidant capacity.
Assuntos
Carotenoides/análise , Fabaceae/química , Alimentos Fortificados , Ferro/farmacocinética , Oryza/química , Animais , Disponibilidade Biológica , Carotenoides/administração & dosagem , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Grupo dos Citocromos b/genética , Grupo dos Citocromos b/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Regulação da Expressão Gênica , Hemoglobinas/metabolismo , História Antiga , Ferro/sangue , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fenóis/análise , Ácido Fítico/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Transferrina/genética , Transferrina/metabolismoRESUMO
Iron is the fourth most abundant element on Earth and the most abundant metal in the human body. This element is crucial for life because almost all organisms need iron for several biological activities. This is the case with pathogenic organisms, which are at the vanguard in the battle with the human host for iron. The latest regulates Fe concentration through several iron-containing proteins, such as transferrin. The transferrin receptor transports iron to each cell that needs it and maintains it away from pathogens. Parasites have developed several strategies to obtain iron as the expression of specific transferrin receptors localized on plasma membrane, internalized through endocytosis. Signal transduction pathways related to the activation of the receptor have functional importance in proliferation. The study of transferrin receptors and other proteins with action in the signaling networks is important because these proteins could be used as therapeutic targets due to their specificity or to differences with the human counterpart. In this work, we describe proteins that participate in signal transduction processes, especially those that involve transferrin endocytosis, and we compare these processes with those found in T. brucei, T. cruzi, Leishmania spp., and E. histolytica parasites.
Assuntos
Endocitose/genética , Ferro/metabolismo , Parasitos/metabolismo , Transferrina/metabolismo , Animais , Antígenos CD/genética , Membrana Celular/genética , Membrana Celular/metabolismo , Humanos , Parasitos/patogenicidade , Receptores da Transferrina/genética , Transdução de Sinais/genética , Transferrina/genéticaRESUMO
Iron metabolism plays an important role in the pathogenesis of lung cancer. This study aimed to investigate the effect of gene silencing of iron regulatory protein-2 (IRP2) on mRNA and protein expression of transferrin (Tf), transferrin receptor (TfR), and ferritin (Fn) in A549 lung cancer cells. A549 cells were cultured and divided into a liposome control group, a liposome + oligonucleotide (SCODN) control group, and a Lipofectamine + antisense oligonucleotide (ASODN) group. RT-PCR and Western blotting were used to detect mRNA and protein expression of Tf, TfR, and Fn. We found no significant change in Tf mRNA expression among the 3 groups (P = 0.078). TfR and Fn mRNA expressions in the ASODN group notably decreased compared to the liposome and SCODN groups (P < 0.01). IRP2 and TfR protein expressions in the ASODN group were significantly lower than in the liposome or SCODN groups (P < 0.05), whereas no significant change in Tf protein expression was observed between the 3 groups (P = 0.088). Fn protein expression in the ASODN group was significantly higher than in the liposome or SCODN group (P < 0.05). IRP2 can regulate the expression of TfR and Fn by changing its own protein expression and thereby regulate iron metabolism.
Assuntos
Proteína 2 Reguladora do Ferro/genética , Ferro/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Linhagem Celular Tumoral , Ferritinas/genética , Ferritinas/metabolismo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína 2 Reguladora do Ferro/metabolismo , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Transferrina/genética , Transfecção , Transferrina/genética , Transferrina/metabolismoRESUMO
In insects, a rapid and massive synthesis of antimicrobial peptides (AMPs) is activated through signaling pathways (Toll and Imd) to combat invading microbial pathogens. However, it is still unclear whether different types of bacteria provoke specific responses. Immune response mechanisms and the activation of specific genes were investigated by challenging Apis mellifera workers with the Gram-negative bacterium Serratia marcescens or the Gram-positive bacterium Micrococcus luteus. The immune system responded by activating most genes of the Toll and Imd pathways, particularly AMP genes. However, genes specifically regulated by M. luteus or S. marcescens were not detected, suggesting an interaction between the signaling pathways that lead to immune effectors synthesis. Despite this finding, kappaB motifs in the 5'-UTRs of selected genes suggest a pathway-specific control of AMP and transferrin-1 gene expression. Regulation by miRNAs was also investigated and revealed a number of candidates for the post-transcriptional regulation of immune genes in bees.
Assuntos
Abelhas/microbiologia , Abelhas/fisiologia , Regulação da Expressão Gênica , Micrococcus luteus/fisiologia , Serratia marcescens/fisiologia , Animais , Abelhas/genética , Abelhas/imunologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , MicroRNAs/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transferrina/genética , Transferrina/metabolismoRESUMO
BACKGROUND: Given mounting evidence for adverse effects from excess manganese exposure, it is critical to understand host factors, such as genetics, that affect manganese metabolism. METHODS: Archived blood samples, collected from 332 Mexican women at delivery, were analyzed for manganese. We evaluated associations of manganese with functional variants in three candidate iron metabolism genes: HFE [hemochromatosis], TF [transferrin], and ALAD [δ-aminolevulinic acid dehydratase]. We used a knockout mouse model to parallel our significant results as a novel method of validating the observed associations between genotype and blood manganese in our epidemiologic data. RESULTS: Percentage of participants carrying at least one copy of HFE C282Y, HFE H63D, TF P570S, and ALAD K59N variant alleles was 2.4%, 17.7%, 20.1%, and 6.4%, respectively. Percentage carrying at least one copy of either C282Y or H63D allele in HFE gene was 19.6%. Geometric mean (geometric standard deviation) manganese concentrations were 17.0 (1.5) µg/l. Women with any HFE variant allele had 12% lower blood manganese concentrations than women with no variant alleles (ß = -0.12 [95% CI = -0.23 to -0.01]). TF and ALAD variants were not significant predictors of blood manganese. In animal models, Hfe(-/-) mice displayed a significant reduction in blood manganese compared with Hfe(+/+) mice, replicating the altered manganese metabolism found in our human research. CONCLUSIONS: Our study suggests that genetic variants in iron metabolism genes may contribute to variability in manganese exposure by affecting manganese absorption, distribution, or excretion. Genetic background may be critical to consider in studies that rely on environmental manganese measurements.
Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Manganês/sangue , Proteínas de Membrana/genética , Sintase do Porfobilinogênio/genética , Transferrina/genética , Animais , Feminino , Genótipo , Proteína da Hemocromatose , Humanos , Ferro/sangue , Ferro/metabolismo , Manganês/metabolismo , Espectrometria de Massas , México , Camundongos , Camundongos Knockout , Modelos Animais , Reação em Cadeia da Polimerase Multiplex , Polimorfismo de Nucleotídeo Único/genética , Período Pós-Parto , Análise de Regressão , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Atômica , Adulto JovemRESUMO
There have been few studies on the mutations that cause heterozygous beta-thalassemia and how they affect the iron profile. One hundred and thirty-eight individuals were analyzed, 90 thalasemic ß° and 48 thalasemic ß(+), identified by classical and molecular methods. Mutations in the hemochromatosis (HFE) gene, detected using PCR-RFLP, were found in 30.4% of these beta-thalassemic patients; heterozygosity for H63D (20.3%) was the most frequent. Ferritin levels and transferrin saturation were similar in beta-thalassemics with and without mutations in the HFE gene. Ferritin concentrations were significantly higher in men and in individuals over 40 years of age. Transferrin saturation also was significantly higher in men, but only in those without HFE gene mutations. There was no significant difference in the iron profile among the ß° and ß(+) thalassemics, with and without HFE gene mutations. The frequency of ferritin values above 200 ng/mL in women and 300 ng/mL in men was also similar in ß° and ß(+) thalassemics (P > 0.72). Our conclusion is that ferritin levels are variable in the beta-thalassemia, trait regardless of the type of beta-globin mutation. Furthermore, HFE gene polymorphisms do not change the iron profile in these individuals.
Assuntos
Ferritinas/sangue , Hemocromatose/genética , Transferrina/análise , Talassemia beta/sangue , Talassemia beta/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Ferritinas/genética , Heterozigoto , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Mutação/genética , Reação em Cadeia da Polimerase , Fatores Sexuais , Transferrina/genéticaRESUMO
Transferrin (Tf) is a ß-globulin protein that transports iron ions in mammalian cells. It contributes to innate immunity to microbial pathogens, primarily by limiting microbial access to iron. Thus, polymorphisms present in bovine Tf could potentially underlie inherited differences in mastitis resistance and milk production traits. We detected three novel single-nucleotide polymorphisms of the Tf gene in Chinese native cattle by screening for genetic variation of Tf in 751 individuals of three Chinese cattle breeds, namely China Holstein, Luxi Yellow and Bohai Black, using PCR-RFLP and DNA sequencing techniques. The three new SNPs, g.-1748G>A ss250608649, g.13942T>C ss250608650, and g.14037A>G ss250608651, had allele frequencies of 85.9, 86.3 and 92.5%, 64.5, 73.3 and 65.0%, and 67.6, 73.7 and 60.0%, respectively. SNP g.-1748G>A was located in the 5' flanking region of Tf. SNP g.14037A>G was located in intron 8 of Tf. SNP g.13942T>C, located in exon 8 of Tf, was a synonymous mutation (TTA > CTA), encoding a leucine (326 aa) in the Tf protein. Associations of the Tf SNPs with milk traits were also analyzed. Significant (P < 0.05) relationships among the Tf polymorphisms, somatic cell scores (SCS), and milk productive traits were observed. Cows with genotypes TT (g.13942T>C), GG (g.-1748G>A) and AG (g.14037A>G) had a lower SCS and higher protein levels and 305-day milk yield. Nineteen combinations of different haplotypes from the three SNPs were identified in Chinese Holstein cattle. The haplotype combination ATA/GCA, GCA/GCA and GCG/ GTA was dominant in cows with a lower SCS, a higher protein level and a higher 305-day milk yield, respectively. Moreover, the gene expression level of Tf was higher in mastitis-affected mammary tissues than in normal mammary tissues. These results suggest that the Tf gene affects milk production, as well as mastitis-resistance traits, in Chinese Holsteins.
Assuntos
Leite , Polimorfismo de Nucleotídeo Único/genética , Transferrina/genética , Animais , Bovinos , Variação Genética/genética , Genótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição/genética , Análise de Sequência de DNARESUMO
BACKGROUND: Neonatal growth is a complex process involving genetic and environmental factors. Polymorphisms in the hemochromatosis (HFE) iron regulatory genes have been shown to modify transport and toxicity of lead which is known to affect birth weight. METHODS: We investigated the role of HFE C282Y, HFE H63 D, and transferrin (TF) P570 S gene variants in modifying the association of lead and infant birthweight in a cohort of Mexican mother-infant pairs. Subjects were initially recruited between 1994-1995 from three maternity hospitals in Mexico City and 411 infants/565 mothers had archived blood available for genotyping. Multiple linear regression models, stratified by either maternal/infant HFE or TF genotype and then combined with interaction terms, were constructed examining the association of lead and birthweight after controlling for covariates. RESULTS: 3.1%, 16.8% and 17.5% of infants (N=390) and 1.9%, 14.5% and 18.9% of mothers (N=533) carried the HFE C282Y, HFE H63D, and TF P570 S variants, respectively. The presence of infant HFE H63 D variants predicted 110.3 g (95% CI -216.1, -4.6) decreases in birthweight while maternal HFE H63 D variants predicted reductions of 52.0 g (95% CI -147.3 to 43.2). Interaction models suggest that both maternal and infant HFE H63 D genotype may modify tibia lead's effect on infant birthweight in opposing ways. In our interaction models, maternal HFE H63 D variant carriers had a negative association between tibia lead and birthweight. CONCLUSIONS: These results suggest that the HFE H63 D genotype modifies lead's effects on infant birthweight in a complex fashion that may reflect maternal-fetal interactions with respect to the metabolism and transport of metals.
Assuntos
Peso ao Nascer/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/genética , Ferro/metabolismo , Chumbo/toxicidade , Proteínas de Membrana/genética , Transferrina/genética , Carga Corporal (Radioterapia) , Estudos de Coortes , Feminino , Variação Genética , Genótipo , Hemocromatose/genética , Proteína da Hemocromatose , Humanos , Recém-Nascido , México , Polimorfismo Genético , Gravidez , Estudos ProspectivosRESUMO
The bovine transferrin gene (TF) is located at 125 cM on bovine chromosome 1 (BTA1); it codes for transferrin, a glycoprotein that is highly conserved in many species and that is responsible for iron transport. The TF gene has been located in several QTL regions, and some transferrin classes have been associated with fat and milk yields. We analyzed by means of allele-specific oligonucleotide real-time PCR the c.1455A>G SNP in exon 12 of the TF cDNA sequence (accession number U02564), which induces an Asp/Gly substitution at position 469 of the peptide. The c.1455A>G SNP was assayed in eight Spanish cattle breeds, as well as in two groups of Holstein-Friesian animals that had the highest and lowest estimated breeding values for milk fat yield. Analysis of the cSNP showed balanced frequencies in all breeds, with a mean of 0.44. Evaluation of a potential association between the cSNP and the groups of Holstein-Friesian animals selected for milk fat yield showed a significant association (P < 0.0006); the G allele was associated with high fat production. Significant differences in genotypic frequencies between the groups were also detected (P < 0.0028). These results lead us to suggest that the TF gene has an effect on milk fat yield.
Assuntos
Bovinos/genética , Lipídeos/biossíntese , Leite/química , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único/genética , Transferrina/genética , Animais , Cruzamento , Frequência do Gene/genética , Genótipo , Espanha , CaudaRESUMO
Iron seems to be an essential factor in myelination and oligodendrocyte (OLGc) biology. However, the specific role of iron in these processes remains to be elucidated. Iron deficiency (ID) imposed to developing rats has been a relevant model to understand the role of iron in oligodendrogenesis and myelination. During early development ID causes specific changes in myelin composition, including a lower relative content of cholesterol, proteolipid protein (PLP), and myelin basic protein 21 (MBP21). These changes could be a consequence of the adverse effects of ID on OLGc development and function. We subsenquently studied the possible corrective effect of a single intracranial injection (ICI) of apotransferrin (aTf) on myelin formation in ID rats OLGc migration and differentiation after an ICI of aTf was evaluated at 3 days of age. ID increased the number of proliferating and undifferentiated cells in the corpus callosum (CC), while a single aTf injection reverts these effects, increasing the number of mature cells and myelin formation. Overall, results of a series of studies supports the concept that iron may affect OLGc development at early stages of embryogenesis rather than during late development. Myelin composition is altered by a limited iron supply, changes that can be reverted by a single injection of aTf.
Assuntos
Diferenciação Celular/fisiologia , Ferro/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Animais , Diferenciação Celular/genética , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Deficiências de Ferro , Bainha de Mielina/genética , Bainha de Mielina/metabolismo , Transferrina/genética , Transferrina/metabolismoRESUMO
BACKGROUND: Given the association between iron deficiency and lead absorption, we hypothesized that variants in iron metabolism genes would predict higher blood lead levels in young children. OBJECTIVE: We examined the association between common missense variants in the hemochromatosis (HFE) and transferrin (TF) genes and blood lead levels in 422 Mexican children. METHODS: Archived umbilical cord blood samples were genotyped for HFE (H63D and C282Y) and TF (P570S) variants. Blood lead was measured at 24, 30, 36, 42, and 48 months of age. A total of 341 subjects had at least one follow-up blood lead level available and data available on covariates of interest for inclusion in the longitudinal analyses. We used random-effects models to examine the associations between genotype (HFE, TF, and combined HFE + TF) and repeated measures of blood lead, adjusting for maternal blood lead at delivery and child's concurrent anemia status. RESULTS: Of 422 children genotyped, 17.7, 3.3, and 18.9% carried the HFE H63D, HFE C282Y, and TF P570S variants, respectively. One percent of children carried both the HFE C282Y and TF P570S variants, and 3% of children carried both the HFE H63D and TF P570S variants. On average, carriers of either the HFE (beta = 0.11, p = 0.04) or TF (beta = 0.10, p = 0.08) variant had blood lead levels that were 11% and 10% higher, respectively, than wild-type subjects. In models examining the dose effect, subjects carrying both variants (beta = 0.41, p = 0.006) had blood lead 50% higher than wild-type subjects and a significantly higher odds of having a blood lead level > 10 microg/dL (odds ratio = 18.3; 95% confidence interval, 1.9-177.1). CONCLUSIONS: Iron metabolism gene variants modify lead metabolism such that HFE variants are associated with increased blood lead levels in young children. The joint presence of variant alleles in the HFE and TF genes showed the greatest effect, suggesting a gene-by-gene-by-environment interaction.
Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Ferro/metabolismo , Chumbo/sangue , Proteínas de Membrana/genética , Transferrina/genética , Sequência de Bases , Pré-Escolar , Primers do DNA , Feminino , Triagem de Portadores Genéticos , Genótipo , Proteína da Hemocromatose , Humanos , Lactente , Masculino , México , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Starch gel electrophoresis was used for examining the transferrin gene locus (Tf) and two esterase gene loci (Est-1 and Est-D1) of a pirarucu (Arapaima gigas) population sample collected from Santa Cruz Lake, Tefé River, Amazonas, Brazil. The Tf locus was tentatively classified as being polymorphic, showing two double-banded patterns (Tf(12) and Tf(22)) of the three theoretically expected ones (Tf(11), Tf(12) and Tf(22)), presumably controlled by two co-dominant alleles, Tf(1) and Tf(2). The monotony detected in pirarucu Tf locus genotypes showing a very high proportion of the double-banded heterozygote pattern Tf(12) (95% of the sampled individuals) may indicate the possibility of their having come from representatives of the same brood begotten by a pair of fish, where a single-banded Tf(11) homozygote pattern male would have crossed with a single-banded Tf(22) homozygote pattern female, or vice versa. One zone of electrophoretic activity was detected in esterase, presumably controlled by a monomorphic Est-1 locus with the fixed allele Est-1(1) where all individuals showed the single-banded Est-1(11) homozygote pattern. Esterase-D also displayed one zone of electrophoretic activity, presumably controlled by a monomorphic Est-D1 locus with a fixed allele Est-D1(1) where all individuals revealed the single-banded Est-D1(11) genotype pattern. The monotony comprised by single-banded genotype patterns in both esterase systems tested may also indicate the possibility of the individuals from the sample examined having come from representatives of the same brood begotten by a pair of fish with both the male and female having the same genotypes.
Assuntos
Esterases/genética , Proteínas de Peixes/genética , Peixes/genética , Transferrina/genética , Alelos , Animais , Brasil , Eletroforese em Gel de Amido/métodos , Feminino , Genótipo , Geografia , Masculino , Polimorfismo GenéticoRESUMO
Starch gel electrophoresis was used for examining the transferrin gene locus (Tf) and two esterase gene loci (Est-1 and Est-D1) of a pirarucu (Arapaima gigas) population sample collected from Santa Cruz Lake, Tefé River, Amazonas, Brazil. The Tf locus was tentatively classified as being polymorphic, showing two double-banded patterns (Tf 12 and Tf 22) of the three theoretically expected ones (Tf 11, Tf 12 and Tf 22), presumably controlled by two co-dominant alleles, Tf 1 and Tf 2. The monotony detected in pirarucu Tf locus genotypes showing a very high proportion of the double-banded heterozygote pattern Tf 12 (95% of the sampled individuals) may indicate the possibility of their having come from representatives of the same brood begotten by a pair of fish, where a single-banded Tf 11 homozygote pattern male would have crossed with a single-banded Tf 22 homozygote pattern female, or vice versa. One zone of electrophoretic activity was detected in esterase, presumably controlled by a monomorphic Est-1 locus with the fixed allele Est-11 where all individuals showed the single-banded Est-111 homozygote pattern. Esterase-D also displayed one zone of electrophoretic activity, presumably controlled by a monomorphic Est-D1 locus with a fixed allele Est-D11 where all individuals revealed the single-banded Est-D111 genotype pattern. The monotony comprised by single-banded genotype patterns in both esterase systems tested may also indicate the possibility of the individuals from the sample examined having come from representatives of the same brood begotten by a pair of fish with both the male and female having the same genotypes.
Assuntos
Animais , Masculino , Feminino , Esterases/genética , Peixes/genética , Proteínas de Peixes/genética , Transferrina/genética , Alelos , Brasil , Eletroforese em Gel de Amido/métodos , Genótipo , Geografia , Polimorfismo GenéticoRESUMO
The trabecular meshwork (TM) is the main outflow pathway in the mammalian eye. Oxidative damage to TM cells has been suggested to be an important cause of impairment of TM functions, leading to deficient drainage of aqueous humor, with deleterious consequences to the eye. Transferrin, a metalloprotein involved in iron transport, has been characterized as an intrinsic eye protein. Since transferrin is implicated in the control of oxidative stress, the objective of the present study was to determine if a bovine TM cell line (CTOB) synthesizes and secretes transferrin. The CTOB cell line was cultured in the presence of 35S-methionine and the incubation medium was submitted to immunoprecipitation. Total RNAs from CTOB and isolated bovine TM (freshly isolated, incubated or not) were subjected to the reverse transcription-polymerase chain reaction and the amplification products were sequenced. Also, both CTOB and histological TM preparations were processed for transferrin immunolocalization. A labeled peptide of about 80 kDa, the expected size for transferrin, was immunopurified from CTOB samples obtained from the incubation assays. The reverse transcription-polymerase chain reaction and sequencing experiments detected the presence of transferrin mRNA in CTOB and isolated bovine TM. Reactivity to antibodies against transferrin was observed both in CTOB and TM. The results obtained in all of these experiments indicated that the TM is capable of synthesizing and secreting transferrin. The possible implications for the physiology of the eye are discussed.
Assuntos
Animais , Bovinos , Malha Trabecular , Transferrina/biossíntese , Transferrina , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Imunoprecipitação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro/biossíntese , Análise de Sequência de RNA , Malha Trabecular/metabolismo , Transferrina/genéticaRESUMO
The trabecular meshwork (TM) is the main outflow pathway in the mammalian eye. Oxidative damage to TM cells has been suggested to be an important cause of impairment of TM functions, leading to deficient drainage of aqueous humor, with deleterious consequences to the eye. Transferrin, a metalloprotein involved in iron transport, has been characterized as an intrinsic eye protein. Since transferrin is implicated in the control of oxidative stress, the objective of the present study was to determine if a bovine TM cell line (CTOB) synthesizes and secretes transferrin. The CTOB cell line was cultured in the presence of 35S-methionine and the incubation medium was submitted to immunoprecipitation. Total RNAs from CTOB and isolated bovine TM (freshly isolated, incubated or not) were subjected to the reverse transcription-polymerase chain reaction and the amplification products were sequenced. Also, both CTOB and histological TM preparations were processed for transferrin immunolocalization. A labeled peptide of about 80 kDa, the expected size for transferrin, was immunopurified from CTOB samples obtained from the incubation assays. The reverse transcription-polymerase chain reaction and sequencing experiments detected the presence of transferrin mRNA in CTOB and isolated bovine TM. Reactivity to antibodies against transferrin was observed both in CTOB and TM. The results obtained in all of these experiments indicated that the TM is capable of synthesizing and secreting transferrin. The possible implications for the physiology of the eye are discussed.
Assuntos
Malha Trabecular/metabolismo , Transferrina/biossíntese , Transferrina/metabolismo , Animais , Bovinos , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Imunoprecipitação , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA , Transferrina/genéticaRESUMO
Transferrin, the iron carrier protein, has been shown to be involved in oligodendroglial cell differentiation in the central nervous system but little is known about its role in the peripheral nervous system. In the present work, we have studied the presence of transferrin and of its mRNA in rat sciatic nerves and in Schwann cells isolated at embryonic and adult ages as well as during the regeneration process that follows nerve crush. We have also studied the correlation between the expression of the mRNAs of transferrin and the expression of mature myelin markers in the PNS. We show that transferrin is present in whole sciatic nerves at late stages of embryonic life as well as at postnatal day 4 and in adult rats. We demonstrate for the first time, that in normal conditions, the transferrin mRNA is expressed in Schwann cells isolated from sciatic nerves between embryonic days 14 and 18, being absent at later stages of development and in adult animals. In adult rats, 3 days after sciatic nerve crushing, the mRNA of transferrin is expressed in the injured nerve, but 7 days after injury its expression disappears. Transferrin protein in the sciatic nerve closely follows the expression of its mRNA indicating that under these circumstances, it appears to be locally synthesized. Transferrin in the PNS could have a dual role. During late embryonic ages it could be locally synthesized by differentiating Schwann cells, acting as a pro-differentiating factor. A similar situation would occur during the regeneration that follows Wallerian degeneration. In the adult animals on the other hand, Schwann cells could pick up transferrin from the circulation or/and from the axons, sub serving possible trophic actions closely related to myelin maintenance.