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1.
Mol Genet Metab ; 140(3): 107670, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37542766

RESUMO

Acute hepatic porphyria (AHP) is a group of four rare inherited diseases, each resulting from a deficiency in a distinct enzyme in the heme biosynthetic pathway. Characterized by acute neurovisceral symptoms that may mimic other medical and psychiatric conditions, lack of recognition of the disease often leads to a delay in diagnosis and initiation of effective treatment. Biochemical testing for pathway intermediates that accumulate when the disease is active forms the basis for screening and establishing a diagnosis. Subsequent genetic analysis identifies the pathogenic variant, supporting screening of family members and genetic counseling. Management of AHP involves avoidance of known exogenous and hormonal triggers, symptomatic treatment, and prevention of recurrent attacks. Here we describe six case studies from our own real-world experience to highlight current recommendations and challenges associated with the diagnosis and long-term management of the disease.


Assuntos
Porfobilinogênio , Porfirias Hepáticas , Humanos , Porfirias Hepáticas/diagnóstico , Porfirias Hepáticas/genética , Porfirias Hepáticas/terapia , Sintase do Porfobilinogênio , Heme/genética
2.
Photosynth Res ; 157(2-3): 147-157, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37140874

RESUMO

We present here the life and the work of Paul A. Castelfranco (1921-2021), a very special person who was not only a top chemist of chlorophyll biosynthesis, but also made major contributions on fatty acid oxidation, acetate metabolism and cellular organization. He led an extraordinary and exemplary life as a human being. We present here both his personal life as well as his scientific life, which is followed by reminiscences by William Breidenbach, Kevin Smith, Alan Stemler, Ann Castelfranco, and John Castelfranco. As the subtitle of this Tribute implies, till the end Paul was a scientist par excellence, an intellectual with unlimited curiosity, a humanist, and a man of enduring religious faith. We all miss him dearly.

3.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674729

RESUMO

To redirect carbon flux from the γ-aminobutyric acid (GABA) shunt to the δ-aminolevulinic acid (ALA) biosynthetic pathway, we disrupted the GABA shunt route of the model cyanobacterium Synechocystis sp. PCC 6803 by inactivating Gdc, the gene-encoding glutamate decarboxylase. The generated ΔGdc strain exhibited lower intracellular GABA and higher ALA levels than the wild-type (WT) one. The ΔGdc strain's ALA levels were ~2.8 times higher than those of the WT one when grown with levulinic acid (LA), a competitive inhibitor of porphobilinogen synthase. Abiotic stress conditions including salinity induced by 10 mM NaCl and cold at 4 °C increased the ALA levels in ΔGdc up to ~2.5 and 5 ng g−1 cell DW, respectively. The highest ALA production in the ΔGdc cyanobacteria grown in BG11 medium was triggered by glucose induction, followed by glutamate supplementation with 60 mM of LA, thereby resulting in ~360 ng g−1 cell DW of ALA, that is >300-fold higher ALA accumulation than that observed in ΔGdc cyanobacteria grown in normal medium. Increased levels of the gdhA (involved in the interconversion of α-ketoglutarate to glutamate) and the hemA (a major regulatory target of the ALA biosynthetic pathway) transcripts occurred in ΔGdc cyanobacteria grown under modified growth conditions. Our study provides critical insight into the facilitation of ALA production in cyanobacteria.


Assuntos
Synechocystis , Synechocystis/genética , Synechocystis/metabolismo , Ácido Aminolevulínico/metabolismo , Ácido gama-Aminobutírico/metabolismo , Ácido Glutâmico/metabolismo
4.
Mol Biol (Mosk) ; 57(6): 1085-1097, 2023.
Artigo em Russo | MEDLINE | ID: mdl-38062963

RESUMO

δ-Aminolevulinic acid dehydratase (ALAD) is a key enzyme of the cytoplasmic heme biosynthesis pathway. The primary structure of the ALAD gene, the multimeric structure of the ALAD/hemB protein, and ALAD expression during the annual reproductive cycle were studied in the cold-water marine sponge Halisarca dujardinii. The results implicated the GATA-1 transcription factor and DNA methylation in regulating ALAD expression. Re-aggregation of sponge cells was accompanied by a decrease in ALAD expression and a change in the cell content of an active ALAD/hemB form. Further study of heme biosynthesis and the role of ALAD/hemB in morphogenesis of basal animals may provide new opportunities for treating pathologies in higher animals.


Assuntos
Poríferos , Animais , Heme/biossíntese , Heme/metabolismo , Poríferos/enzimologia , Poríferos/metabolismo , Sintase do Porfobilinogênio/genética , Sintase do Porfobilinogênio/metabolismo
5.
Drug Chem Toxicol ; 45(6): 2483-2487, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34334063

RESUMO

The deficiency of essential minerals increases lead absorption and thus aggravates the lead-induced toxic effects. This study was aimed at understanding the ameliorative effect of essential minerals on lead-induced alterations in hematological parameters in rats. To achieve this objective, the study was conducted in 320 male Wistar albino rats, grouped into two, with equal numbers. One of the groups of rats was fed on a mineral-supplemented food referred to as a 'well-nourished group' and another group 'undernourished group' on food without mineral supplements. Each group of rats was further subdivided into 'Subjects' and 'Controls.' Subjects of both the groups of rats were exposed to 500 ppm lead acetate up to a period of 300 days (10 months) in drinking water and the role of minerals on lead-induced alterations in hematological parameters was evaluated. A significant decrease (p < 0.001) in hemoglobin (Hb) and δ-aminolevulinic acid dehydratase (δ-ALAD) levels and a significant increase (p < 0.001) in urinary δ-aminolevulinic acid (δ-ALAU) levels were seen in subjects without mineral supplementation compared to those fed on a mineral-enriched diet. A positive correlation was observed between blood lead levels (PbB) and δ-ALAU (r = 0.792) and a negative correlation with Hb (r = -0.926) and δ-ALAD (r = -0.836) in the subjects. These changes were very prominent in the undernourished subjects when compared to the well-nourished subjects. Observations of the present study indicate that mineral supplementation with ongoing lead exposure may help in minimizing the absorption of lead and reduce lead-induced toxic effects.


Assuntos
Chumbo , Minerais , Animais , Masculino , Ratos , Acetatos , Ácido Aminolevulínico , Hemoglobinas , Chumbo/toxicidade , Minerais/farmacologia , Sintase do Porfobilinogênio , Ratos Wistar
6.
Drug Chem Toxicol ; 45(3): 1276-1283, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-32907406

RESUMO

Lead tops the list of developmental toxicants released by industry into the environment according to Commission for Environmental Corporation. Hydrilla verticillata is an aquatic weed and rich source of variable nutrients and chemical constituents like saponins, vitamins, minerals, antioxidants, amino acids, detoxifying agents, etc. This weed is used in a beneficial way to detoxify lead in fish model. The fish were treated with sublethal concentration of lead to induce liver damage and fed with supplementary feed containing 20% of hydrilla dry powder. The present work revealed that lead accumulation is highly toxic to liver. Lead toxicity increased the expressions of cytochrome P450 1 A (CYP1A) and cytochrome P450 3 A (CYP3A) when compared to control. The metal binding stress proteins, heat shock proteins (Hsp60 & Hsp70) and metallothionein were also upregulated due to lead toxicity. Lead intoxicated fish exhibited reduced δ-aminolevulinic acid dehydratase activity in the blood, leading to reduced red blood cell count and changes in cell morphology. The lead toxicity also decreases the level of liver marker enzymes alanine transaminase, aspartate transaminase in serum. In hydrilla supplemented protective group, there was amelioration of these changes. Administration of supplementary feed to the lead intoxicated protective group significantly decreased the expressions of CYP1A, CYP3A, Hsp60, Hsp70 and metallothionein genes. The red blood cell count in lead intoxicated fish was maintained almost normal due to the protective action of Hydrilla verticillata in the diet. The observed increase in the enzymes, which further confirmed the protective effect of Hydrilla verticillata against lead induced toxicity.


Assuntos
Cyprinidae , Hydrocharitaceae , Animais , Citocromo P-450 CYP3A/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Chumbo/metabolismo , Chumbo/toxicidade , Fígado , Metalotioneína/metabolismo
7.
Environ Sci Technol ; 55(18): 12272-12280, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34473489

RESUMO

Lead (Pb) exposure is a widespread wildlife conservation threat. Although commonly associated with Pb-based ammunition from big-game hunting, small mammals (e.g., ground squirrels) shot for recreational or pest-management purposes represent a potentially important Pb vector in agricultural regions. We measured the responses of avian scavengers to pest-shooting events and examined their Pb exposure through consumption of shot mammals. There were 3.4-fold more avian scavengers at shooting fields relative to those at fields with no recent shooting, and avian scavengers spent 1.8-fold more time feeding after recent shooting events. We isotopically labeled shot ground squirrels in the field with an enriched 15N isotope tracer; 6% of avian scavengers sampled within a 39 km radius reflected this tracer in their blood. However, 33% of the avian scavengers within the average foraging dispersal distance of nests (0.6-3.7 km) were labeled, demonstrating the importance of these shooting fields as a source of food for birds nesting in close proximity. Additionally, Pb concentrations in 48% of avian scavengers exceeded subclinical poisoning benchmarks for sensitive species (0.03-0.20 µg/g w/w), and those birds exhibited reduced δ-aminolevulinic acid dehydratase activity, indicating a biochemical effect of Pb. The use of shooting to manage small mammal pests is a common practice globally. Efforts that can reduce the use of Pb-based ammunition may lessen the negative physiological effects of Pb exposure on avian scavengers.


Assuntos
Intoxicação por Chumbo , Chumbo , Animais , Aves , Peixes , Mamíferos
8.
Indian J Clin Biochem ; 36(1): 94-99, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33505133

RESUMO

Activated carbon fabrics (ACF) mask prevents the absorption of lead and reduce its adverse effects of human health. Aim of this study to know the blood lead level and its effects on heme biosynthesis and hematological parameters after using 2 months activated carbon fabric mask of battery manufacturing workers (BMW). Blood lead level, heme biosynthesis and hematological parameters were measured by using standard method. Blood lead level (P < 0.001, - 13.5%) was significantly decreased, activated δ-aminolevulinic acid dehydratase (P < 0.001, 11.97%) and non-activated δ- aminolevulinic acid dehydratase (P < 0.001, 23.17%) enzyme activity were significantly increased, however, the ratio of activated to Non-activated δ- ALAD (P < 0.001, - 10.13%) was significantly decreased, urinary excretion of δ- aminolevulinic acid (P < 0.001, - 10.49%) and porphobilinogen (P < 0.001, - 7.38%) were significantly decreased after using 2 months ACF mask as compared to before using mask of BMW. Hematological parameters i.e Hb (P < 0.05, 13.42%), PCV (P < 0.05, 7.23%), MCV (P < 0.05, 1.9%) were significantly increased and total WBC count (P < 0.05, - 5.18%) was significantly decreased after using 2 months ACF mask as compared to before using mask of BMW. Two months using ACF mask reduces the blood lead level and improves the δ-ALDH activity and hematological parameters, decreases the urinary excretion of δ-ALA, PBG of battery manufacturing workers. Therefore, the regular using of ACF mask is beneficial to prevent the lead absorption and its adverse effects on human health.

9.
Plant J ; 98(4): 622-638, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30666736

RESUMO

Fumarylacetoacetate hydrolase (FAH) catalyses the final step of the tyrosine degradation pathway, which is essential to animals but was of unknown importance in plants until we found that mutation of Short-day Sensitive Cell Death1 (SSCD1), encoding Arabidopsis FAH, results in cell death under short-day conditions. The sscd1 mutant accumulates succinylacetone (SUAC), an abnormal metabolite caused by loss of FAH. Succinylacetone is an inhibitor of δ-aminolevulinic acid (ALA) dehydratase (ALAD), which is involved in chlorophyll (Chl) biosynthesis. In this study, we investigated whether sscd1 cell death is mediated by Chl biosynthesis and found that ALAD activity is repressed in sscd1 and that protochlorophyllide (Pchlide), an intermediate of Chl biosynthesis, accumulates at lower levels in etiolated sscd1 seedlings. However, it was interesting that Pchlide in sscd1 might increase after transfer from light to dark and that HEMA1 and CHLH are upregulated in the light-dark transition before Pchlide levels increased. Upon re-illumination after Pchlide levels had increased, reactive oxygen species marker genes, including singlet oxygen-induced genes, are upregulated, and the sscd1 cell death phenotype appears. In addition, Arabidopsis WT seedlings treated with SUAC mimic sscd1 in decline of ALAD activity and accumulation of Pchlide as well as cell death. These results demonstrate that increase in Pchlide causes cell death in sscd1 upon re-illumination and suggest that a decline in the Pchlide pool due to inhibition of ALAD activity by SUAC impairs the repression of ALA synthesis from the light-dark transition by feedback control, resulting in activation of the Chl biosynthesis pathway and accumulation of Pchlide in the dark.


Assuntos
Arabidopsis/enzimologia , Arabidopsis/metabolismo , Morte Celular/fisiologia , Hidrolases/metabolismo , Protoclorifilida/metabolismo , Aldeído Oxirredutases/metabolismo , Ácido Aminolevulínico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clorofila/biossíntese , Regulação da Expressão Gênica de Plantas , Heptanoatos/metabolismo , Hidroliases/metabolismo , Hidrolases/genética , Luz , Liases/metabolismo , Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Plântula/genética , Plântula/metabolismo , Transcriptoma
10.
Artigo em Inglês | MEDLINE | ID: mdl-32567994

RESUMO

The objective of this study was to investigate the effects of chronic environmental lead (Pb) exposure in blood lead level (BLL), δ-aminolevulinic acid dehydratase (ALAD) activity, hemoglobin (Hb) amount and hematocrit (Hct) value in primary schoolchildren and adults. Blood was obtained for BLL, ALAD, Hb and Hct measurements in 23 primary schoolchildren (girls and boys) and 117 adult residents (women and men) living in three villages (Kelmend, Boletin and Zhazhë) defined by concentric circles 2, 3 and 5 km in radius drawn around from the smelter-refinery complex "Trepça"in Zveçan and in Koliq village 40 km away. As expected, BLLs were substantially higher in the schoolchildren from smelter area compared with control (11 ± 4.2 µg/L and 6.9 ± 1.6 µg/L respectively) and in adult residents from Kelmend, Boletin and Zhazhë (24 ± 11.8, 12 ± 4.5, 11 ± 5.4 and 8.0 ± 2.8 µg/L respectively). Blood ALAD activity of children in Zhazhë is 16% inhibited compared to control and blood ALAD activity in adults in villages from smelter area is 32, 3%, 48, 4% and 17, 8% inhibited compared to control. There is no difference of Hb and Hct values in schoolchildren from Zhazhë and in adult residents from Kelmend and Zhazhë compared with control. Results of this study provide evidence of moderate inverse correlation between BLL and ALAD activity in both examined cohorts from smelter area. The inhibition of ALAD activity in primary schoolchildren and adults occurred at blood lead levels < 24 µg/L; consequently it can cause an increase of δ- Aminolevulinic acid.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/sangue , Hemoglobinas/análise , Chumbo/sangue , Mineração , Sintase do Porfobilinogênio/sangue , Adulto , Biomarcadores/sangue , Criança , Feminino , Hematócrito , Humanos , Kosovo , Intoxicação por Chumbo/sangue , Masculino , População Rural , Instituições Acadêmicas
11.
Physiol Mol Biol Plants ; 24(6): 1117-1126, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30425428

RESUMO

The purpose of this study was to determine the concentration of some metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Ca and Mg) in soil of serpentine and limestone sites, their bioaccumulation and impact on some biochemical parameters in T. luanica, T. kosovarica and T. albanica plants. T. kosovarica and T. albanica grows in serpentine soil, while T. luanica grow in limestone soil. The research showed that concentrations of Cd, Co, Cr, Fe, Mn and Ni were significantly higher at serpentine soil sites in comparison with limestone sites, while concentrations of Pb, Cd, Co and Cr in bulbs, leaves and seeds were under the limit of detection. The concentration of Ni in plant samples of T. kosovarica was significantly higher in comparison with its concentration in T. albanica, but it was under the limit of detection in T. luanica. Moreover, concentrations of Al and Fe in leaves of T. kosovarica and T. albanica were higher in comparison with T. luanica. The concentration of Mg was significantly higher in T. kosovarica and T. albanica than in T. luanica. The δ-aminolevulinic acid dehydratase activity, malondialdehyde and glutathione contents in leaves of T. luanica were higher in comparison with T. kosovarica and T. albanica. In addition, the amounts of total chlorophyll and δ-aminolevulinic acid (ALA) in leaves of T. albanica were higher in comparison with T. kosovarica and T. luanica. Our findings show that target organs of metal accumulation in three Tulip species appears to be leaves > seeds > bulbs, while the biochemical parameters show that limestone sites represent a less stressful habitat for growing these plant species in comparison with serpentine sites.

12.
J Infect Chemother ; 23(12): 852-855, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28673558

RESUMO

A hemin-requiring Pseudomonas aeruginosa small-colony variant (SCV) was isolated from the blood of an octogenarian male-patient with double pneumonitis. The isolate was capable of growing on both sheep blood and chocolate agars but not on MacConkey agars without blood ingredient. Furthermore, the isolate revealed to grow only around the X-factor impregnated discs when examined using the X and V disc strips. However, not only RapID-NH system but also the VITEK2 system failed to identify the isolate. The isolate was finally identified as P. aeruginosa by the sequence of the 16S rRNA genes and the MALDI-TOF MS analysis. Interestingly, the isolate represented positive reaction for δ-aminolaevulinic acid (ALA)-test despite the requirement of hemin. Detailed analysis indicated that the isolate produced protoporphyrin IX from ALA. Therefore, the reason for the hemin dependence was deduced the dysfunction of hemH-encoded ferrochelatase behaving at the end of biosynthetic pathway of heme. However, the genetic analysis of hemH gene demonstrated no variations of both the DNA and the amino-acid sequences. To the best of our knowledge, this is the first clinical isolation of a hemin-dependent P. aeruginosa SCV from blood.


Assuntos
Pneumonia Bacteriana/sangue , Infecções por Pseudomonas/sangue , Pseudomonas aeruginosa/isolamento & purificação , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Ácido Aminolevulínico/química , Sequência de Bases , Meios de Cultura , Hemina/genética , Humanos , Masculino , Protoporfirinas/química , Pseudomonas aeruginosa/genética , RNA Ribossômico 16S/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Orig Life Evol Biosph ; 47(1): 93-119, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27207103

RESUMO

Attempts to develop a credible prebiotic route to tetrapyrroles have relied on enzyme-free recapitulation of the extant biosynthesis, but this process has foundered from the inability to form the pyrrole porphobilinogen (PBG) in good yield by self-condensation of the precursor δ-aminolevulinic acid (ALA). PBG undergoes robust oligomerization in aqueous solution to give uroporphyrinogen (4 isomers) in good yield. ALA, PBG, and uroporphyrinogen III are universal precursors to all known tetrapyrrole macrocycles. The enzymic formation of PBG entails carbon-carbon bond formation between the less stable enolate/enamine of one ALA molecule (3-position) and the carbonyl/imine (4-position) of the second ALA molecule; without enzymes, the first ALA reacts at the more stable enolate/enamine (5-position) and gives the pyrrole pseudo-PBG. pseudo-PBG cannot self-condense, yet has one open α-pyrrole position and is proposed to be a terminator of oligopyrromethane chain-growth from PBG. Here, 23 analogues of ALA have been subjected to density functional theoretical (DFT) calculations, but no motif has been identified that directs reaction at the 3-position. Deuteriation experiments suggested 5-(phosphonooxy)levulinic acid would react preferentially at the 3- versus 5-position, but a hybrid condensation with ALA gave no observable uroporphyrin. The results suggest efforts toward a biomimetic, enzyme-free route to tetrapyrroles from ALA should turn away from structure-directed reactions and focus on catalysts that orient the two aminoketones to form PBG in a kinetically controlled process, thereby avoiding formation of pseudo-PBG.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Evolução Química , Porfobilinogênio/química , Tetrapirróis/química , Ácido Aminolevulínico/química , Cinética , Origem da Vida
14.
Am J Physiol Heart Circ Physiol ; 310(11): H1439-47, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27037373

RESUMO

Oxidation of the soluble guanylate cyclase (sGC) heme promotes loss of regulation by nitric oxide (NO) and depletion of sGC. We hypothesized that angiotensin II (ANG II) stimulation of mitochondrial superoxide by its type 1 receptor could function as a potential inhibitor of heme biosynthesis by ferrochelatase, and this could decrease vascular responsiveness to NO by depleting sGC. These processes were investigated in a 24-h organoid culture model of bovine coronary arteries (BCA) with 0.1 µM ANG II. Treatment of BCA with ANG II increased mitochondrial superoxide, depleted mitochondrial superoxide dismutase (SOD2), ferrochelatase, and cytochrome oxidase subunit 4, and sGC, associated with impairment of relaxation to NO. These processes were attenuated by organoid culture with 8-bromo-cGMP and/or δ-aminolevulinic acid (a stimulator of sGC by protoporphyrin IX generation and heme biosynthesis). Organoid culture with Mito-TEMPOL, a scavenger of mitochondrial matrix superoxide, also attenuated ANG II-elicited ferrochelatase depletion and loss of relaxation to NO, whereas organoid culture with Tempol, an extramitochondrial scavenger of superoxide, attenuated the loss of relaxation to NO by ANG II, but not ferrochelatase depletion, suggesting cytosolic superoxide could be an initiating factor in the loss of sGC regulation by NO. The depletion of cytochrome oxidase subunit 4 and sGC (but not catalase) suggests that sGC expression may be very sensitive to depletion of heme caused by ANG II disrupting ferrochelatase activity by increasing mitochondrial superoxide. In addition, cGMP-dependent activation of protein kinase G appears to attenuate these ANG II-stimulated processes through both preventing SOD2 depletion and increases in mitochondrial and extramitochondrial superoxide.


Assuntos
Angiotensina II/farmacologia , Vasos Coronários/efeitos dos fármacos , Ferroquelatase/metabolismo , Heme/metabolismo , Mitocôndrias/efeitos dos fármacos , Guanilil Ciclase Solúvel/metabolismo , Superóxidos/metabolismo , Animais , Bovinos , Vasos Coronários/enzimologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Regulação para Baixo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Ativadores de Enzimas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Mitocôndrias/enzimologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Organoides , Superóxido Dismutase/metabolismo , Técnicas de Cultura de Tecidos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
15.
Ecotoxicol Environ Saf ; 129: 250-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27054706

RESUMO

Liver and blood δ-aminolevulinic acid dehydratase (ALA-D) inhibition by exposure to sub-lethal lead concentrations over time in Nile tilapia (Oreochromis niloticus) were investigated. All three lead concentrations (1mgkg(-1), 10mgkg(-1) and 100mgkg(-1)) significantly inhibited ALA-D activity in blood (319±29.2; 180±14.6 and 172±19µmols(-1)h(-1)L(-1) respectively) and liver (302±5.84; 201±41.4 and 93±22.1µmols(-1)h(-1)L(-1)) 24h after injection relative to controls (blood: 597±37.0µmols(-1)h(-1)L(-1); liver: 376±23.1µmols(-1)h(-1)L(-1)). Blood ALA-D was greatly inhibited in all but the highest lead dose. Fish were then exposed to 1mgkg(-1) lead for 9 days, and presented short-term hyperglycemia, decreased hemoglobin and hematocrit values and time-dependent blood ALA-D activity inhibition, corroborating blood ALA-D activity as being more suitable for investigating lead effects, showing dose and time-dependent ALA-D inhibition after lead exposure. The results of the present study also demonstrated that fish size affects blood ALA-D activity, as fish from the 24-h assay, which were slightly smaller (approximately 200g), showed higher ALA-D inhibition in response to lead exposure when compared to the fish from the 9-day assay (approximately 500g). Thus, fish size should always be taken into account both in the field and in laboratory settings, and efforts should be made to obtain uniform fish size samples for biomarker studies.


Assuntos
Ciclídeos/sangue , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Sintase do Porfobilinogênio/sangue , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Relação Dose-Resposta a Droga , Hematócrito , Hemoglobinas/metabolismo , Hiperglicemia/sangue , Hiperglicemia/induzido quimicamente , Concentração Inibidora 50 , Fígado/metabolismo , Sintase do Porfobilinogênio/antagonistas & inibidores
16.
Circ Res ; 113(3): 279-87, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23720443

RESUMO

RATIONALE: Heme plays a critical role in gas exchange, mitochondrial energy production, and antioxidant defense in cardiovascular system. The mitochondrial transporter ATP-binding cassette (ABC) B10 has been suggested to export heme out of the mitochondria and is required for normal hemoglobinization of erythropoietic cells and protection against ischemia-reperfusion injury in the heart; however, its primary function has not been established. OBJECTIVE: The aim of this study was to identify the function of ABCB10 in heme synthesis in cardiac cells. METHODS AND RESULTS: Knockdown of ABCB10 in cardiac myoblasts significantly reduced heme levels and the activities of heme-containing proteins, whereas supplementation with δ-aminolevulinic acid reversed these defects. Overexpression of mitochondrial δ-aminolevulinic acid synthase 2, the rate-limiting enzyme upstream of δ-aminolevulinic acid export, failed to restore heme levels in cells with ABCB10 downregulation. ABCB10 and heme levels were increased by hypoxia, and reversal of ABCB10 upregulation caused oxidative stress and cell death. Furthermore, ABCB10 knockdown in neonatal rat cardiomyocytes resulted in a significant delay of calcium removal from the cytoplasm, suggesting a relaxation defect. Finally, ABCB10 expression and heme levels were altered in failing human hearts and mice with ischemic cardiomyopathy. CONCLUSIONS: ABCB10 plays a critical role in heme synthesis pathway by facilitating δ-aminolevulinic acid production or export from the mitochondria. In contrast to previous reports, we show that ABCB10 is not a heme exporter and instead is required for the early mitochondrial steps of heme biosynthesis.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Heme/biossíntese , Mitocôndrias Cardíacas/fisiologia , Miócitos Cardíacos/fisiologia , Animais , Células Cultivadas , Heme/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ratos
17.
Artigo em Inglês | MEDLINE | ID: mdl-24875442

RESUMO

Based on exposure frequency and intrinsic toxicity, lead (Pb) ranks one of the highest priority toxic materials. Continuous regulation of environmental Pb exposure has contributed to dramatically diminished exposure levels of Pb, for example, blood level of Pb. However, the safety level of Pb is not established, as low-level exposure to Pb still shows severe toxicity in high susceptible population and late onset of some diseases from early exposure. In the present study, we focused on food-borne Pb exposure and found broad variations in Pb exposure levels via food among countries. In addition, there are genetic or ethnical variations in Pb-targeted and protective genes. Moreover, various epigenetic alterations were induced by Pb poisoning. Therefore, we suggest a systemic approach including governmental (public) and individual prevention from Pb exposure with continuous biological monitoring and genetic or epigenetic consideration.


Assuntos
Exposição Ambiental , Epigênese Genética , Contaminação de Alimentos/análise , Chumbo/toxicidade , Suscetibilidade a Doenças/epidemiologia , Saúde Ambiental/legislação & jurisprudência , Humanos , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/etiologia , Polimorfismo Genético
18.
Beilstein J Org Chem ; 10: 2414-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25383111

RESUMO

Grafting of δ-aminolevulinic acid (1) moieties on the narrow periphery of a ß-cyclodextrin (ß-CD) derivative through hydrolysable bonds was implemented, in order to generate a water-soluble, molecular/drug carrier with the capacity to undergo intracellular transformation into protoporphyrin IX (PpIX), an endogenous powerful photosensitizer for photodynamic therapy (PDT). The water-soluble derivative 2 was prepared by esterifying δ-azidolevulinic acid with heptakis(6-hydroxyethylamino-6-deoxy)-ß-cyclodextrin, with an average degree of substitution, DS = 3. Delivery of water-soluble, colorless 2 to cells resulted in intense red fluorescence registered by confocal microscopy, evidently due to the engagement of the intracellular machinery towards formation of PpIX. Conjugate 2 was further complexed with a fluorescein-labeled model guest molecule which was successfully transported into the cells, thereby demonstrating the bimodal action of the derivative. The present work shows the versatility of CDs in smart applications and constitutes advancement to our previously shown PpIX-ß-CD conjugation both in terms of water solubility and lack of aggregation.

19.
Intern Med ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462517

RESUMO

Hereditary coproporphyria (HCP) is caused by a partial deficiency of coproporphyrinogen oxidase during heme biosynthesis. Givosiran is approved for the treatment of acute hepatic porphyria. We herein report the case of a 47-year-old woman with HCP. Monthly givosiran administration improved her subjective symptoms and reduced her δ-aminolevulinic acid (ALA) and porphobilinogen (PBG) levels to the normal range. However, givosiran was discontinued after six months due to a decreased renal function. The patient's ALA and PBG levels remained within the normal ranges, and her HCP-related symptoms resolved more than 2 years after the discontinuation of givosiran.

20.
J Occup Health ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283726

RESUMO

OBJECTIVES: Whether the known positive association between blood lead (PbB) levels and urinary δ-aminolevulinic acid (ALAU) also exists at relatively low PbB levels (<40 µg/dL) remains unclear. We aimed to investigate this association at lower PbB levels. METHODS: We analyzed data from biannual medical examinations of workers at a Japanese factory from August 2013 to August 2023. We excluded records from female workers and those with missing data, resulting in a dataset consisting of 1396 records from 155 male workers. We employed mixed-effect linear regression models with a random intercept for workers and additional adjustments for age and smoking status. RESULTS: The median PbB level across all the analyzed records was 8 µg/dL (range: 1, 31 µg/dL). Significant positive associations were observed between PbB and ALAU, with a one-unit increase in natural logarithm-transformed PbB corresponding to a 10.0% increase in ALAU (95% CI: 2.7, 17.9%). Categorized PbB analyses showed a 23.8% increase in ALAU (95% CI: 2.7, 49.2%) for PbB levels at 20-24 µg/dL and an 83.1% increase (95% CI: 30.1, 157.7%) for PbB levels ≥25 µg/dL, compared to those <5 µg/dL. The exposure-response curve analysis indicated a plateau followed by an increasing trend. CONCLUSIONS: A positive and non-linear association between PbB and ALAU levels was observed at relatively low PbB levels.

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