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1.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542447

RESUMO

Sonodynamic therapy (SDT), utilizing ultrasound (US) and sonosensitizers, holds immense potential as a noninvasive and targeted treatment for a variety of deep-seated tumors. However, the clinical translation of SDT is hampered by several key limitations in sonosensitizers, especially their low aqueous stability and poor cellular uptake. In this study, non-ionic polysorbate (Tween 80, T80) was adopted to formulate effective nanocarriers for the safe and efficient delivery of sonosensitizers to cancer cells. Mitochondria-targeting triphenylphosphonium (TPP)-conjugated chlorin e6 (Ce6) sonosensitizer was loaded into T80-based micelles for efficient SDT. Pro-oxidant piperlongumine (PL) was co-encapsulated with TPP-conjugated Ce6 (T-Ce6) in T80 micelles to enable combination chemo-SDT. T80 micelles substantially enhanced the cellular internalization of T-Ce6. As a result, T80 micelles loaded with T-Ce6 and PL [T80(T-Ce6/PL)] significantly elevated intracellular reactive oxygen species (ROS) generation in MCF-7 human breast cancer cells upon US exposure. Moreover, T-Ce6 exhibited selective accumulation within the mitochondria, leading to efficient cell death under US irradiation. Importantly, T80(T-Ce6/PL) micelles caused cancer-specific cell death by selectively triggering apoptosis in cancer cells through PL. This study demonstrated the feasibility of using T80(T-Ce6/PL) micelles for efficient and cancer-specific combination chemo-SDT.


Assuntos
Nanopartículas , Neoplasias , Compostos Organofosforados , Porfirinas , Humanos , Polissorbatos , Linhagem Celular Tumoral , Micelas , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Porfirinas/metabolismo , Neoplasias/tratamento farmacológico
2.
Angew Chem Int Ed Engl ; 63(14): e202319690, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38320965

RESUMO

Given the scarcity of novel antibiotics, the eradication of bacterial biofilm infections poses formidable challenges. Upon bacterial infection, the host restricts Fe ions, which are crucial for bacterial growth and maintenance. Having coevolved with the host, bacteria developed adaptive pathways like the hemin-uptake system to avoid iron deficiency. Inspired by this, we propose a novel strategy, termed iron nutritional immunity therapy (INIT), utilizing Ga-CT@P nanocomposites constructed with gallium, copper-doped tetrakis (4-carboxyphenyl) porphyrin (TCPP) metal-organic framework, and polyamine-amine polymer dots, to target bacterial iron intakes and starve them. Owing to the similarity between iron/hemin and gallium/TCPP, gallium-incorporated porphyrin potentially deceives bacteria into uptaking gallium ions and concurrently extracts iron ions from the surrounding bacteria milieu through the porphyrin ring. This strategy orchestrates a "give and take" approach for Ga3+/Fe3+ exchange. Simultaneously, polymer dots can impede bacterial iron metabolism and serve as real-time fluorescent iron-sensing probes to continuously monitor dynamic iron restriction status. INIT based on Ga-CT@P nanocomposites induced long-term iron starvation, which affected iron-sulfur cluster biogenesis and carbohydrate metabolism, ultimately facilitating biofilm eradication and tissue regeneration. Therefore, this study presents an innovative antibacterial strategy from a nutritional perspective that sheds light on refractory bacterial infection treatment and its future clinical application.


Assuntos
Infecções Bacterianas , Gálio , Porfirinas , Humanos , Ferro/metabolismo , Hemina/metabolismo , Bactérias/metabolismo , Antibacterianos/metabolismo , Biofilmes , Gálio/farmacologia , Porfirinas/farmacologia , Porfirinas/metabolismo , Infecções Bacterianas/tratamento farmacológico , Homeostase , Íons/metabolismo , Polímeros/metabolismo
3.
Angew Chem Int Ed Engl ; 63(6): e202314450, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38150561

RESUMO

Previous aptamers for porphyrins and metalloporphyrins were all guanine-rich sequences that can fold in G-quadruplex structures. Due to stacking-based binding, these aptamers can hardly tell different porphyrins apart, and they can also bind other planar molecules, hindering their practical applications. In this work, we used the capture selection method to obtain aptamers for hemin and protoporphyrin IX (PPIX). The hemin aptamer (Hem1) features two highly conserved repeating binding loops, and it cannot form a G-quadruplex, which was supported by its Mg2+ -dependent but K+ -independent hemin binding and CD spectroscopy. Isothermal titration calorimetry revealed much higher enthalpy change for the new aptamer, and the best aptamer showed a Kd of 43 nM hemin. Hem1 can also enhance the peroxidase-like activity of hemin. This work demonstrates that aptamers have alternative ways to bind porphyrins allowing selective recognition of different porphyrins.


Assuntos
Aptâmeros de Nucleotídeos , Quadruplex G , Porfirinas , Hemina/química , Aptâmeros de Nucleotídeos/química , Porfirinas/metabolismo , Peroxidases/metabolismo
4.
Semin Liver Dis ; 43(4): 446-459, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37973028

RESUMO

The porphyrias are a group of metabolic disorders that are caused by defects in heme biosynthesis pathway enzymes. The result is accumulation of heme precursors, which can cause neurovisceral and/or cutaneous photosensitivity. Liver is commonly either a source or target of excess porphyrins, and porphyria-associated hepatic dysfunction ranges from minor abnormalities to liver failure. In this review, the first of a three-part series, we describe the defects commonly found in each of the eight enzymes involved in heme biosynthesis. We also discuss the pathophysiology of the hepatic porphyrias in detail, covering epidemiology, histopathology, diagnosis, and complications. Cellular consequences of porphyrin accumulation are discussed, with an emphasis on oxidative stress, protein aggregation, hepatocellular cancer, and endothelial dysfunction. Finally, we review current therapies to treat and manage symptoms of hepatic porphyria.


Assuntos
Neoplasias Hepáticas , Porfirias Hepáticas , Porfirias , Porfirinas , Humanos , Doenças Raras/complicações , Porfirinas/metabolismo , Porfirias/diagnóstico , Porfirias/terapia , Porfirias/complicações , Porfirias Hepáticas/epidemiologia , Porfirias Hepáticas/terapia , Porfirias Hepáticas/complicações , Heme/metabolismo , Neoplasias Hepáticas/metabolismo
5.
J Exp Zool A Ecol Integr Physiol ; 339(10): 915-924, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37522474

RESUMO

Using a rat model of type 1 diabetes (T1D) obtained by treatment with streptozotocin, an antibiotic that destroys pancreatic ß-cells, we evaluated the influence of subsequent hyperglycemia on the morphology and physiology of the Harderian gland (HG). HG is located in the medial corner of the orbit of many terrestrial vertebrates and, in rodents, is characterized by the presence of porphyrins, which being involved in the phototransduction, through photo-oxidation, produce reactive oxygen species activating the autophagy pathway. The study focused on the expression of some morphological markers involved in cell junction formation (occludin, connexin-43, and α-tubulin) and mast cell number (MCN), as well as autophagic and apoptotic pathways. The expression of enzymes involved in steroidogenesis [steroidogenic acute regulatory protein (StAR), and 3ß-hydroxysteroid dehydrogenase (3ß-HSD)] and the level of lipid peroxidation by thiobarbituric acid reactive species assay were also evaluated. The results strongly indicate, for the first time, that T1D has a negative impact on the pathophysiology of rat HG, as evidenced by increased oxidative stress, morphological and biochemical alterations, hyperproduction and secretion of porphyrins, increased MCN, reduced protein levels of StAR and 3ß-HSD, and, finally, induced autophagy and apoptosis. All the combined data support the use of the rat HG as a suitable experimental model to elucidate the molecular damage/survival pathways elicited by stress conditions.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Glândula de Harder , Porfirinas , Animais , Ratos , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Glândula de Harder/metabolismo , Porfirinas/efeitos adversos , Porfirinas/metabolismo , Estreptozocina/efeitos adversos , Estreptozocina/metabolismo
6.
J Mol Recognit ; 36(8): e3017, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37025015

RESUMO

The G-quadruplex planar-ligand complex is used to detect heavy metal cations such as Ag+ , Cu2+ , Pb2+ , Hg2+ , organic molecules, nucleic acids, and proteins. The interaction of the three planar porphyrins (L1), 5,10,15,20-tetrakis (1-ethyl-1-λ4 -pyridine-4-yl) porphyrin (L2), and 5,10,15,20-tetrakis (1-methyl-1-λ4 -pyridine-4-yl) porphyrin (L3), coming from the porphyrin family, with G-quadruplex obtained from human DNA telomeres in the presence of lithium, sodium, potassium, rubidium, cesium, magnesium, and calcium ions was studied by molecular dynamics simulation. When G-quadruplex containing divalent ions of magnesium and calcium interacts with L1, L2, and L3 ligands, the hydrogen bonds of the lower G-quadruplex sheet are more affected by ligands and the distance between guanines in the lower tetrad increases. In the case of G-quadruplex interactions containing monovalent ions with ligands, the hydrogen bond between the sheets does not follow a specific trend. For example, in the presence of lithium ions, the upper and middle sheets are more affected by ligands, while they are less affected by ligands in the presence of sodium. The binding pocket and the binding energy of the three ligands to the G-quadruplex were also obtained in the various systems. The results show that ligands make the G-quadruplex more stable through the penetration between the sheets and the interaction with the loops. Among the ligands mentioned, the interaction level of the ligand L2 is greater than the others. Our calculations are consistent with the previous experimental observations so that it can help to understand the molecular mechanism of porphyrin interaction and its derivatives with the G-quadruplex.


Assuntos
Quadruplex G , Porfirinas , Humanos , Porfirinas/metabolismo , Ligantes , Lítio , Cálcio , Magnésio , Cátions , Piridinas , Sódio
7.
Molecules ; 28(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37049670

RESUMO

Standard therapies for colorectal cancer cannot eliminate or sufficiently reduce the metastasis process. Photodynamic therapy (PDT) may be an alternative to minimizing this problem. Here, we examined the cellular localization of selected porphyrins and determined whether free-base and manganese (III) metallated porphyrins may limit colon cancer cells' (HT29) or normal colon epithelial cells' (CCD 841 CoTr) motility in vitro. White light irradiation was used to initiate the photodynamic effect. Porphyrin uptake by the cells was determined by porphyrin fluorescence measurements through the use of confocal microscopy. Free-base porphyrin was found in cells, where it initially localized at the edge of the cytoplasm and later in the perinuclear area. The concentrations of porphyrins had no effect on cancer cell migration but had a significant effect on normal cell motility. Due to the low concentrations of porphyrins used, no changes in F-actin filaments of the cellular cytoskeleton were detected. Signal transmission via connexons between neighbouring cells was limited to a maximum of 40 µm for HT29 and 30 µm for CCD 841 CoTr cells. The tested porphyrins differed in their activity against the tumor and normal cells' migration capacity. Depending on the porphyrin used and the type of cells, their migration changed in relation to the control sample. The use of white light may change the activity of the porphyrins relative to the migratory capacity of the cells. The aim of the present study was to analyse the intracellular localization of tested porphyrins and their influence on the mobility of cells after irradiation with harmless white light.


Assuntos
Neoplasias do Colo , Fotoquimioterapia , Porfirinas , Humanos , Porfirinas/farmacologia , Porfirinas/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Luz , Neoplasias do Colo/tratamento farmacológico
8.
Molecules ; 28(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37110868

RESUMO

Heme b, which is characterized by a ferrous ion and a porphyrin macrocycle, acts as a prosthetic group for many enzymes and contributes to various physiological processes. Consequently, it has wide applications in medicine, food, chemical production, and other burgeoning fields. Due to the shortcomings of chemical syntheses and bio-extraction techniques, alternative biotechnological methods have drawn increasing attention. In this review, we provide the first systematic summary of the progress in the microbial synthesis of heme b. Three different pathways are described in detail, and the metabolic engineering strategies for the biosynthesis of heme b via the protoporphyrin-dependent and coproporphyrin-dependent pathways are highlighted. The UV spectrophotometric detection of heme b is gradually being replaced by newly developed detection methods, such as HPLC and biosensors, and for the first time, this review summarizes the methods used in recent years. Finally, we discuss the future prospects, with an emphasis on the potential strategies for improving the biosynthesis of heme b and understanding the regulatory mechanisms for building efficient microbial cell factories.


Assuntos
Heme , Porfirinas , Heme/metabolismo , Vias Biossintéticas , Porfirinas/metabolismo , Engenharia Metabólica/métodos
9.
Biochemistry ; 62(7): 1262-1273, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36947867

RESUMO

The ancient protein TSPO (translocator protein 18kD) is found in all kingdoms and was originally identified as a binding site of benzodiazepine drugs. Its physiological function remains unclear, although porphyrins are conserved ligands. Several crystal structures of bacterial TSPO and nuclear magnetic resonance structures of a mouse form have revealed monomer and dimer configurations, but there have been no reports of structures with a physiological ligand. Here, we present the first X-ray structures of Rhodobacter sphaeroides TSPO with a physiological ligand bound. Two different variants (substituting threonine for alanine at position 139 (A139T) and phenylalanine for alanine at position 138 (A138F)) yielded well-diffracting crystals giving structures of both apo- and heme-containing forms. Both variants have wild-type micromolar affinity for heme and protoporphyrin IX, but A139T has very low ability to accelerate the breakdown of porphyrin in the presence of light and oxygen. The binding of heme to one protomer of the dimer of either mutant induces a more rigid structure, both in the heme-binding protomer and the protomer without heme bound, demonstrating an allosteric response. Ensemble refinement of the X-ray data reveals distinct regions of altered flexibility in response to single heme binding to the dimer. The A139T variant shows a more rigid structure overall, which may relate to extra hydrogen bonding of waters captured in the heme crevice. As TSPO has been suggested to have a role in heme delivery from mitochondria to the cytoplasm, the new structures provide potential clues regarding the structural basis of such activity.


Assuntos
Proteínas de Bactérias , Heme , Porfirinas , Rhodobacter sphaeroides , Alanina , Sítios de Ligação , Proteínas de Transporte/metabolismo , Heme/metabolismo , Ligantes , Porfirinas/metabolismo , Subunidades Proteicas/metabolismo , Proteínas de Bactérias/metabolismo
10.
Int J Mol Sci ; 24(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36982348

RESUMO

Chlorophyll and heme are essential molecules for photosynthesis and respiration, which are competing branches of the porphyrin metabolism pathway. Chlorophyll and heme balance regulation is very important for the growth and development of plants. The chimeric leaves of Ananas comosus var. bracteatus were composed of central photosynthetic tissue (PT) and marginal albino tissue (AT), which were ideal materials for the study of porphyrin metabolism mechanisms. In this study, the regulatory function of ALA content on porphyrin metabolism (chlorophyll and heme balance) was revealed by comparing PT and AT, 5-Aminolevulinic Acid (ALA) exogenous supply, and interference of hemA expression. The AT remained similar in porphyrin metabolism flow level to the PT by keeping an equal ALA content in both tissues, which was very important for the normal growth of the chimeric leaves. As the chlorophyll biosynthesis in AT was significantly inhibited, the porphyrin metabolism flow was directed more toward the heme branch. Both tissues had similar Mg2+ contents; however, Fe2+ content was significantly increased in the AT. The chlorophyll biosynthesis inhibition in the white tissue was not due to a lack of Mg2+ and ALA. A 1.5-fold increase in ALA content inhibited chlorophyll biosynthesis while promoting heme biosynthesis and hemA expression. The doubling of ALA content boosted chlorophyll biosynthesis while decreasing hemA expression and heme content. HemA expression interference resulted in a higher ALA content and a lower chlorophyll content, while the heme content remained at a relatively low and stable level. Conclusively, a certain amount of ALA was important for the stability of porphyrin metabolism and the normal growth of plants. The ALA content appears to be able to regulate chlorophyll and heme content by bidirectionally regulating porphyrin metabolism branch direction.


Assuntos
Ananas , Porfirinas , Porfirinas/metabolismo , Ácido Aminolevulínico/metabolismo , Ananas/metabolismo , Clorofila/metabolismo , Heme/metabolismo
11.
Methods Mol Biol ; 2651: 131-141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36892764

RESUMO

The non-covalent interaction of achiral porphyrins with nucleic acids has been extensively studied, and various macrocycles have been indeed utilized as reporters of different sequences of DNA bases. Nevertheless, few studies have been published on the capability of these macrocycles to discriminate among the various nucleic acid conformations. Circular dichroism spectroscopy allowed to characterize the binding of several cationic and anionic mesoporphyrins and metallo derivatives with Z-DNA, in order to exploit the functionality of these systems as probes, storing system, and logic gate.


Assuntos
DNA Forma Z , Metaloporfirinas , Porfirinas , Porfirinas/metabolismo , Dicroísmo Circular , DNA/metabolismo
12.
Chemistry ; 29(32): e202300408, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36861298

RESUMO

Herein, a host-guest inclusion complex formation between tetra-PEGylated tetraphenylporphyrin with a per-O-methylated cyclodextrin (CD) dimer through the molecular threading process that is physically unexpected to occur is described. Although the molecular size of the PEGylated porphyrin is much greater than that of the CD dimer, the sandwich-type porphyrin/CD dimer 1 : 1 inclusion complex was spontaneously formed in water. The ferrous porphyrin complex binds O2 reversibly in aqueous solution, which functions as an artificial O2 carrier in vivo. Pharmacokinetic study using rats revealed that the inclusion complex showed a long circulation in blood in contrast to the complex without PEG. We further demonstrate the unique host-guest exchange reaction from the PEGylated porphyrin/CD monomer 1/2 inclusion complex to the 1/1 complex with the CD dimer through the complete dissociation process of the CD monomers.


Assuntos
Ciclodextrinas , Porfirinas , Ratos , Animais , Porfirinas/metabolismo , Polímeros , Água , Polietilenoglicóis
13.
Biochemistry ; 62(6): 1191-1196, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36877586

RESUMO

Bacteria that infect the human gut must compete for essential nutrients, including iron, under a variety of different metabolic conditions. Several enteric pathogens, including Vibrio cholerae and Escherichia coli O157:H7, have evolved mechanisms to obtain iron from heme in an anaerobic environment. Our laboratory has demonstrated that a radical S-adenosylmethionine (SAM) methyltransferase is responsible for the opening of the heme porphyrin ring and release of iron under anaerobic conditions. Furthermore, the enzyme in V. cholerae, HutW, has recently been shown to accept electrons from NADPH directly when SAM is utilized to initiate the reaction. However, how NADPH, a hydride donor, catalyzes the single electron reduction of a [4Fe-4S] cluster, and/or subsequent electron/proton transfer reactions, was not addressed. In this work, we provide evidence that the substrate, in this case, heme, facilitates electron transfer from NADPH to the [4Fe-4S] cluster. This study uncovers a new electron transfer pathway adopted by radical SAM enzymes and further expands our understanding of these enzymes in bacterial pathogens.


Assuntos
Proteínas Ferro-Enxofre , Porfirinas , Humanos , Elétrons , Porfirinas/metabolismo , S-Adenosilmetionina/metabolismo , NADP/metabolismo , Proteínas Ferro-Enxofre/química , Ferro/metabolismo , Heme/metabolismo
14.
Molecules ; 28(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36770766

RESUMO

The toxic effects of four cationic porphyrins on various human cells were studied in vitro. It was found that, under dark conditions, porphyrins are almost nontoxic, while, under the action of light, the toxic effect was observed starting from nanomolar concentrations. At a concentration of 100 nM, porphyrins caused inhibition of metabolism in the MTT test in normal and cancer cells. Furthermore, low concentrations of porphyrins inhibited colony formation. The toxic effect was nonlinear; with increasing concentrations of various porphyrins, up to about 1 µM, the effect reached a plateau. In addition to the MTT test, this was repeated in experiments examining cell permeability to trypan blue, as well as survival after 24 h. The first visible manifestation of the toxic action of porphyrins is blebbing and swelling of cells. Against the background of this process, permeability to porphyrins and trypan blue appears. Subsequently, most cells (even mitotic cells) freeze in this swollen state for a long time (24 and even 48 h), remaining attached. Cellular morphology is mostly preserved. Thus, it is clear that the cells undergo mainly necrotic death. The hypothesis proposed is that the concentration dependence of membrane damage indicates a limited number of porphyrin targets on the membrane. These targets may be any ion channels, which should be considered in photodynamic therapy.


Assuntos
Fotoquimioterapia , Porfirinas , Humanos , Porfirinas/farmacologia , Porfirinas/metabolismo , Azul Tripano , Fármacos Fotossensibilizantes/farmacologia , Cátions/farmacologia
15.
J Photochem Photobiol B ; 241: 112670, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36841175

RESUMO

BACKGROUND: Antimicrobial blue light (aBL) kills a variety of bacteria, including Porphyromonas gingivalis. However, little is known about the transcriptomic response of P. gingivalis to aBL therapy. This study was designed to evaluate the selective cytotoxicity of aBL against P. gingivalis over human cells and to further investigate the genetic response of P. gingivalis to aBL at the transcriptome level. METHODS: Colony forming unit (CFU) testing, confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM) were used to investigate the antimicrobial effectiveness of blue light against P. gingivalis. The temperatures of the irradiated targets were measured to prevent overheating. Multiple fluorescent probes were used to quantify reactive oxygen species (ROS) generation after blue-light irradiation. RNA sequencing (RNA-seq) was used to investigate the changes in global gene expression. Following the screening of target genes, real-time quantitative polymerase chain reaction (RT-qPCR) was performed to confirm the regulation of gene expression. RESULTS: A 405 nm aBL at 100 mW/cm2 significantly killed P. gingivalis within 5 min while sparing human gingival fibroblasts (HGFs). No obvious temperature changes were detected in the irradiated surface under our experimental conditions. RNA-seq showed that the transcription of multiple genes was regulated, and RT-qPCR revealed that the expression levels of the genes RgpA and RgpB, which may promote heme uptake, as well as the genes Ftn and FetB, which are related to iron homeostasis, were significantly upregulated. The expression levels of the FeoB-2 and HmuR genes, which are related to hydroxyl radical scavenging, were significantly downregulated. CONCLUSIONS: aBL strengthens the heme uptake and iron export gene pathways while reducing the ROS scavenging pathways in P. gingivalis, thus improving the accumulation of endogenous photosensitizers and enhancing oxidative damage to P. gingivalis.


Assuntos
Cor , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Ferro , Luz , Porfirinas , Porphyromonas gingivalis , Porfirinas/metabolismo , Ferro/metabolismo , Porphyromonas gingivalis/citologia , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo , Porphyromonas gingivalis/efeitos da radiação , Transporte Biológico/genética , Transporte Biológico/efeitos da radiação , Humanos , Gengiva/citologia , Fibroblastos/citologia , Fibroblastos/efeitos da radiação , Radical Hidroxila/metabolismo , Heme/metabolismo , Regulação para Cima/efeitos da radiação , Homeostase/efeitos da radiação , Regulação para Baixo/efeitos da radiação , Viabilidade Microbiana/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Aerobiose , Genes Bacterianos/efeitos da radiação , Regulação Bacteriana da Expressão Gênica/genética , Regulação Bacteriana da Expressão Gênica/efeitos da radiação
16.
Basic Clin Pharmacol Toxicol ; 132(3): 281-291, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36535687

RESUMO

Pregnane X receptor (PXR) is known to stimulate haem synthesis, but detailed knowledge on the effects of PXR activation on porphyrin metabolism in humans is lacking. We utilized a randomized, crossover, open (blinded laboratory) and placebo-controlled trial with 600-mg rifampicin or placebo dosed for a week to investigate the effects of PXR activation on erythrocyte, plasma, faecal and urine porphyrins. Sixteen healthy volunteers participated on the trial, but the number of volunteers for blood and urine porphyrin analyses was 15 while the number of samples for faecal analyses was 14. Rifampicin increased urine pentaporphyrin concentration 3.7-fold (mean 1.80 ± 0.6 vs. 6.73 ± 4.4 nmol/L, p = 0.003) in comparison with placebo. Urine coproporphyrin I increased 23% (p = 0.036). Faecal protoporphyrin IX decreased (mean 31.6 ± 23.5 vs. 19.2 ± 27.8 nmol/g, p = 0.023). The number of blood erythrocytes was slightly elevated, and plasma bilirubin, catabolic metabolite of haem, was decreased. In conclusion, rifampicin dosing elevated the excretion of certain urinary porphyrin metabolites and decreased faecal protoporphyrin IX excretion. As urine pentaporphyrin and coproporphyrin I are not precursors in haem biosynthesis, increased excretion may serve as a hepatoprotective shunt when haem synthesis or porphyrin levels are increased.


Assuntos
Porfirinas , Rifampina , Humanos , Eritrócitos , Voluntários Saudáveis , Heme/metabolismo , Porfirinas/metabolismo , Porfirinas/urina , Rifampina/farmacologia , Receptor de Pregnano X/efeitos dos fármacos , Receptor de Pregnano X/metabolismo
17.
Biomaterials ; 289: 121812, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36152516

RESUMO

Cancer stem cells (CSCs) are the subpopulation of tumor cells with the properties of tumorigenesis, multilineage differentiation potential and self-renewal, which is the driving force of tumor recurrence and metastasis. However, targeting CSCs is still the main challenge in cancer therapy due to their rapid growth and fast mutation rate. Herein, we developed a simple strategy of photodynamic therapy (PDT) targeting CSCs, dependent on much more abundant ribosomes in CSCs. The interactions between positively charged nanoparticles with negatively charged nucleic acids architectures in cancer cells could lead ribosomes targeting as well as CSCs targeting. The co-assembly of simple amino porphyrin (m-TAPP) with short peptide (Fmoc-L3-OMe) formed nanoparticles (NPs) with good biocompatibility and photoactivity, became positively charged due to low pH value of tumour microenvironment, and efficiently accessed cancer cell ribosome, approached cancer cell nuclei, therefore enriched in the fast-amplifying CSCs. The inhibitive effect on CSCs by m-TAPP assemblies was verified by the significant reduction of CSCs markers CD44, CD133 and ribosome amount in cancer cells and tissues. Upon light irradiation, the NPs induced ROS generation to provoke destructive cancer cell ribosome damage and subsequent apoptosis to prevent tumor growth markedly. Based on the assemblies of small organic molecules, our study not only achieves ribosome degradation induced cancer cells apoptosis, but also indicates new possibility of performing CSCs targeting PDT.


Assuntos
Ácidos Nucleicos , Fotoquimioterapia , Porfirinas , Linhagem Celular Tumoral , Humanos , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Ácidos Nucleicos/metabolismo , Peptídeos/metabolismo , Peptídeos/farmacologia , Porfirinas/metabolismo , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ribossomos/metabolismo , Microambiente Tumoral
18.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142411

RESUMO

The protozoan parasite Leishmania, responsible for leishmaniasis, is one of the few aerobic organisms that cannot synthesize the essential molecule heme. Therefore, it has developed specialized pathways to scavenge it from its host. In recent years, some proteins involved in the import of heme, such as LHR1 and LFLVCRB, have been identified, but relevant aspects regarding the process remain unknown. Here, we characterized the kinetics of the uptake of the heme analogue Zn(II) Mesoporphyrin IX (ZnMP) in Leishmania major promastigotes as a model of a parasite causing cutaneous leishmaniasis with special focus on the force that drives the process. We found that ZnMP uptake is an active, inducible, and pH-dependent process that does not require a plasma membrane proton gradient but requires the presence of the monovalent cations Na+ and/or K+. In addition, we demonstrated that this parasite can efflux this porphyrin against a concentration gradient. We also found that ZnMP uptake differs among different dermotropic or viscerotropic Leishmania species and does not correlate with LHR1 or LFLVCRB expression levels. Finally, we showed that these transporters have only partially overlapping functions. Altogether, these findings contribute to a deeper understanding of an important process in the biology of this parasite.


Assuntos
Leishmania major , Leishmaniose Cutânea , Porfirinas , Heme/metabolismo , Humanos , Leishmania major/metabolismo , Leishmaniose Cutânea/parasitologia , Metaloporfirinas , Porfirinas/metabolismo , Prótons
19.
Perspect Biol Med ; 65(3): 415-425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093774

RESUMO

The evolution of self-replicating biological species required the prebiotic evolution of fundamental chemical compounds that facilitate critical redox reactions, including chiefly the oxidation of water, the reduction of molecular oxygen, and redox transitions of partially reduced forms of oxygen (reactive oxygen species). The fundamental catalysts for these reactions are porphyrins. Chemically versatile, photoreactive, and redox-active, porphyrins (or their primary precursor, porphin) are believed to have evolved prebiotically in an enthalpically feasible series of reactions. Found throughout biological kingdoms, porphyrins were incorporated in apoproteins in biological evolution and adapted to the specific redox needs of the organisms in which they were active, including photosynthesis, reactive oxygen species metabolism, and oxidative phosphorylation. They did so by virtue of differing transition metal chelates and tetrapyrrole side chains. This article reviews the prebiotic and biotic evolution of porphyrins and porphyrin-bearing apoproteins and suggests that porphyrins' history in evolution reflects a repurposing of molecular motifs as an efficient mechanism for adaptation to a changing redox environment.


Assuntos
Porfirinas , Apoproteínas/metabolismo , Humanos , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Porfirinas/metabolismo , Espécies Reativas de Oxigênio
20.
Food Funct ; 13(19): 10069-10082, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36093868

RESUMO

Echinacea purpurea polysaccharide (EPP) is a functional compound in Echinacea purpurea. At present, it is generally recognized that plant polysaccharides can regulate the intestinal microecology, but there are few studies on EPP. In this study, we used the digestive model (stomach-small intestine-colon) and a mouse model to study the effect of EPP on intestinal microecology and the mechanism. Also, combined with the microbiome and metabolome analysis methods, the interaction network mechanism of EPP-gut microbiota-metabolites-metabolism was investigated. After EPP was digested by human intestinal microbiota, the microbial diversity changed, with an increase in the relative abundance of Bifidobacterium and a decrease in the abundance of Prevotella, Catenibacterium and Ruminococcus torques. After metabolism in mice, the concentration of short-chain fatty acids increased, the abundances of Muribaculaceae and Alloprevotella increased, and those of Lachnospiraceae and Butyricicoccus decreased. Both in vivo and in vitro experiments revealed that EPP can downregulate the expression of 15 enzymes involved in porphyrin metabolism. In addition, the metabolome results also confirmed that alanine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and glycine, serine and threonine metabolism are regulatory pathways of EPP. Tryptophan, ornithine, tyrosine, leucine, alanine and serine are hallmark metabolites. The cross-cooperation network greatly influenced the microbiota (Lactobacillus, Lachnospiraceae), metabolites (tryptophan, beta-D-fructose 1,6-bisphosphate), and metabolism (glycosphingolipid biosynthesis), suggesting that they may be the key factors mediating the metabolic function of EPP. Therefore, EPP has the effect of enhancing the proliferation of gut-beneficial bacteria that metabolize polysaccharides and produce valuable metabolites.


Assuntos
Echinacea , Microbioma Gastrointestinal , Microbiota , Porfirinas , Alanina/metabolismo , Alanina/farmacologia , Animais , Ácidos Graxos Voláteis/farmacologia , Glicina/metabolismo , Glicoesfingolipídeos/farmacologia , Humanos , Leucina/metabolismo , Metaboloma , Camundongos , Ornitina/metabolismo , Fenilalanina/metabolismo , Polissacarídeos/farmacologia , Porfirinas/metabolismo , Porfirinas/farmacologia , Serina/metabolismo , Treonina/metabolismo , Triptofano/metabolismo , Tirosina
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