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1.
J Cell Mol Med ; 28(8): e18306, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613357

RESUMO

Topical patch delivery of deferoxamine (DFO) has been studied as a treatment for this fibrotic transformation in irradiated tissue. Efficacy of a novel cream formulation of DFO was studied as a RIF therapeutic in unwounded and excisionally wounded irradiated skin. C57BL/6J mice underwent 30 Gy of radiation to the dorsum followed by 4 weeks of recovery. In a first experiment, mice were separated into six conditions: DFO 50 mg cream (D50), DFO 100 mg cream (D100), soluble DFO injections (DI), DFO 1 mg patch (DP), control cream (Vehicle), and irradiated untreated skin (IR). In a second experiment, excisional wounds were created on the irradiated dorsum of mice and then divided into four treatment groups: DFO 100 mg Cream (W-D100), DFO 1 mg patch (W-DP), control cream (W-Vehicle), and irradiated untreated wounds (W-IR). Laser Doppler perfusion scans, biomechanical testing, and histological analysis were performed. In irradiated skin, D100 improved perfusion compared to D50 or DP. Both D100 and DP enhanced dermal characteristics, including thickness, collagen density and 8-isoprostane staining compared to untreated irradiated skin. D100 outperformed DP in CD31 staining, indicating higher vascular density. Extracellular matrix features of D100 and DP resembled normal skin more closely than DI or control. In radiated excisional wounds, D100 facilitated faster wound healing and increased perfusion compared to DP. The 100 mg DFO cream formulation rescued RIF of unwounded irradiated skin and improved excisional wound healing in murine skin relative to patch delivery of DFO.


Assuntos
Desferroxamina , Síndrome da Fibrose por Radiação , Camundongos , Animais , Camundongos Endogâmicos C57BL , Desferroxamina/farmacologia , Desferroxamina/uso terapêutico , Pele , Perfusão
2.
J Neurosci Res ; 102(4): e25334, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38656648

RESUMO

Iron deficiency (ID) has been shown to affect central nervous system (CNS) development and induce hypomyelination. Previous work from our laboratory in a gestational ID model showed that both oligodendrocyte (OLG) and astrocyte (AST) maturation was impaired. To explore the contribution of AST iron to the myelination process, we generated an in vitro ID model by silencing divalent metal transporter 1 (DMT1) in AST (siDMT1 AST) or treating AST with Fe3+ chelator deferoxamine (DFX; DFX AST). siDMT1 AST showed no changes in proliferation but remained immature. Co-cultures of oligodendrocyte precursors cells (OPC) with siDMT1 AST and OPC cultures incubated with siDMT1 AST-conditioned media (ACM) rendered a reduction in OPC maturation. These findings correlated with a decrease in the expression of AST-secreted factors IGF-1, NRG-1, and LIF, known to promote OPC differentiation. siDMT1 AST also displayed increased mitochondrial number and reduced mitochondrial size as compared to control cells. DFX AST also remained immature and DFX AST-conditioned media also hampered OPC maturation in culture, in keeping with a decrease in the expression of AST-secreted growth factors IGF-1, NRG-1, LIF, and CNTF. DFX AST mitochondrial morphology and number showed results similar to those observed in siDMT1 AST. In sum, our results show that ID, induced through two different methods, impacts AST maturation and mitochondrial functioning, which in turn hampers OPC differentiation.


Assuntos
Astrócitos , Diferenciação Celular , Deficiências de Ferro , Oligodendroglia , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Oligodendroglia/metabolismo , Oligodendroglia/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Proteínas de Transporte de Cátions/metabolismo , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Ratos , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Células Precursoras de Oligodendrócitos/metabolismo , Desferroxamina/farmacologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Ferro/metabolismo
3.
Blood Cells Mol Dis ; 107: 102859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820707

RESUMO

We conducted a retrospective cohort study on 663 transfusion-dependent ß-thalassemia patients receiving the same iron chelation monotherapy with deferoxamine, deferiprone, or deferasirox for up to 10 years (median age 31.8 years, 49.9 % females). Patients on all three iron chelators had a steady and significant decline in serum ferritin over the 10 years (median deferoxamine: -170.7 ng/mL, P = 0.049, deferiprone: -236.7 ng/mL, P = 0.001; deferasirox: -323.7 ng/mL, P < 0.001) yet had no significant change in liver iron concentration or cardiac T2*; while noting that patients generally had low hepatic and cardiac iron levels at study start. Median absolute, relative, and normalized changes were generally comparable between the three iron chelators. Patients receiving deferasirox had the highest morbidity and mortality-free survival probability among the three chelators, although the difference was only statistically significant when compared with deferoxamine (P = 0.037). On multivariate Cox regression analysis, there was no significant association between iron chelator type and the composite outcome of morbidity or mortality. In a real-world setting, there is comparable long-term iron chelation effectiveness between the three available iron chelators for patients with mild-to-moderate iron overload.


Assuntos
Transfusão de Sangue , Deferasirox , Deferiprona , Desferroxamina , Quelantes de Ferro , Ferro , Piridonas , Talassemia beta , Humanos , Quelantes de Ferro/uso terapêutico , Talassemia beta/mortalidade , Talassemia beta/terapia , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Feminino , Masculino , Adulto , Estudos Retrospectivos , Desferroxamina/uso terapêutico , Deferiprona/uso terapêutico , Ferro/metabolismo , Deferasirox/uso terapêutico , Piridonas/uso terapêutico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/tratamento farmacológico , Benzoatos/uso terapêutico , Ferritinas/sangue , Adolescente , Triazóis/uso terapêutico , Adulto Jovem , Criança , Resultado do Tratamento , Pessoa de Meia-Idade , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Estudos de Coortes
4.
Mol Pharm ; 21(7): 3218-3232, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885477

RESUMO

Squamous cell carcinoma (SCC) is a common nonmelanoma skin cancer. Radiotherapy plays an integral role in treating SCC due to its characteristics, such as diminished intercellular adhesion, heightened cell migration and invasion capabilities, and immune evasion. These problems lead to inaccurate tumor boundary positioning and radiotherapy tolerance in SCC treatment. Thus, accurate localization and enhanced radiotherapy sensitivity are imperative for effective SCC treatment. To address the existing limitations in SCC therapy, we developed monoglyceride solid lipid nanoparticles (MG SLNs) and enveloped them with the A431 cell membrane (A431 CM) to create A431@MG. The characterization results showed that A431@MG was spherical. Furthermore, A431@MG had specific targeting for A431 cells. In A431 tumor-bearing mice, A431@MG demonstrated prolonged accumulation within tumors, ensuring precise boundary localization of SCC. We further advanced the approach by preparing MG SLNs encapsulating 5-aminolevulinic acid methyl ester (MLA) and desferrioxamine (DFO) with an A431 CM coating to yield A431@MG-MLA/DFO. Several studies have revealed that DFO effectively reduced iron content, impeding protoporphyrin IX (PpIX) biotransformation and promoting PpIX accumulation. Simultaneously, MLA was metabolized into PpIX upon cellular entry. During radiotherapy, the heightened PpIX levels enhanced reactive oxygen species (ROS) generation, inducing DNA and mitochondrial damage and leading to cell apoptosis. In A431 tumor-bearing mice, the A431@MG-MLA/DFO group exhibited notable radiotherapy sensitization, displaying superior tumor growth inhibition. Combining A431@MG-MLA/DFO with radiotherapy significantly improved anticancer efficacy, highlighting its potential to serve as an integrated diagnostic and therapeutic strategy for SCC.


Assuntos
Carcinoma de Células Escamosas , Membrana Celular , Nanopartículas , Radiossensibilizantes , Neoplasias Cutâneas , Animais , Camundongos , Nanopartículas/química , Humanos , Linhagem Celular Tumoral , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Radiossensibilizantes/administração & dosagem , Membrana Celular/metabolismo , Ácido Aminolevulínico/química , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/administração & dosagem , Lipídeos/química , Ensaios Antitumorais Modelo de Xenoenxerto , Desferroxamina/química , Desferroxamina/farmacologia , Camundongos Nus , Feminino , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Lipossomos
5.
Pharmacol Res ; 206: 107264, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876443

RESUMO

Disturbances in copper (Cu) homeostasis have been observed in diabetes and associated complications. Cu is an essential micronutrient that plays important roles in various fundamental biological processes. For example, diabetic cardiomyopathy is associated with elevated levels of Cu in the serum and tissues. Therefore, targeting Cu may be a novel treatment strategy for diabetic complications. This review provides an overview of physiological Cu metabolism and homeostasis, followed by a discussion of Cu metabolism disorders observed during the occurrence and progression of diabetic complications. Finally, we discuss the recent therapeutic advances in the use of Cu coordination complexes as treatments for diabetic complications and their potential mechanisms of action. This review contributes to a complete understanding of the role of Cu in diabetic complications and demonstrates the broad application prospects of Cu-coordinated compounds as potential therapeutic agents.

6.
Int J Mol Sci ; 25(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255991

RESUMO

Deferoxamine (DFO) is a water-soluble iron chelator used pharmacologically for the management of patients with transfusional iron overload. However, DFO is not cell-permeable and has a short plasma half-life, which necessitates lengthy parenteral administration with an infusion pump. We previously reported the synthesis of chitosan (CS) nanoparticles for sustained slow release of DFO. In the present study, we developed solid dispersions and nanoparticles of a carboxymethyl water-soluble chitosan derivative (CMCS) for improved DFO encapsulation and release. CS dispersions and nanoparticles with DFO have been prepared by ironical gelation using sodium triphosphate (TPP) and were examined for comparison purposes. The successful presence of DFO in CMCS polymeric dispersions and nanoparticles was confirmed through FTIR measurements. Furthermore, the formation of CMCS nanoparticles led to inclusion of DFO in an amorphous state, while dispersion of DFO in the polymeric matrix led to a decrease in its crystallinity according to X-ray diffraction (XRD) and differential scanning calorimetry (DSC) results. An in vitro release assay indicated sustained release of DFO from CS and CMCS nanoparticles over 48 h and 24 h, respectively. Application of CMCS-DFO dispersions to murine RAW 264.7 macrophages or human HeLa cervical carcinoma cells triggered cellular responses to iron deficiency. These were exemplified in the induction of the mRNA encoding transferrin receptor 1, the major iron uptake protein, and the suppression of ferritin, the iron storage protein. Our data indicate that CMCS-DFO nanoparticles release bioactive DFO that causes effective iron chelation in cultured cells.


Assuntos
Quitosana , Humanos , Animais , Camundongos , Desferroxamina/farmacologia , Quelantes , Transporte Biológico , Ferro
7.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731540

RESUMO

Deferoxamine, an iron chelator used to treat diseases caused by excess iron, has had a Food and Drug Administration-approved status for many years. A large number of studies have confirmed that deferoxamine can reduce inflammatory response and promote angiogenesis. Blood vessels play a crucial role in sustaining vital life by facilitating the delivery of immune cells, oxygen, and nutrients, as well as eliminating waste products generated during cellular metabolism. Dysfunction in blood vessels may contribute significantly to the development of life-threatening diseases. Anti-angiogenesis therapy and pro-angiogenesis/angiogenesis strategies have been frequently recommended for various diseases. Herein, we describe the mechanism by which deferoxamine promotes angiogenesis and summarize its application in chronic wounds, bone repair, and diseases of the respiratory system. Furthermore, we discuss the drug delivery system of deferoxamine for treating various diseases, providing constructive ideas and inspiration for the development of new treatment strategies.


Assuntos
Desferroxamina , Neovascularização Fisiológica , Desferroxamina/farmacologia , Desferroxamina/uso terapêutico , Humanos , Animais , Neovascularização Fisiológica/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Angiogênese
8.
Glia ; 71(3): 648-666, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36565279

RESUMO

Hypoxic preconditioning is protective in multiple models of injury and disease, but whether it is beneficial for cells transplanted into sites of spinal cord injury (SCI) is largely unexplored. In this study, we analyzed whether hypoxia-related preconditioning protected Schwann cells (SCs) transplanted into the contused thoracic rat spinal cord. Hypoxic preconditioning was induced in SCs prior to transplantation by exposure to either low oxygen (1% O2 ) or pharmacological agents (deferoxamine or adaptaquin). All preconditioning approaches induced hypoxic adaptations, including increased expression of HIF-1α and its target genes. These adaptations, however, were transient and resolved within 24 h of transplantation. Pharmacological preconditioning attenuated spinal cord oxidative stress and enhanced transplant vascularization, but it did not improve either transplanted cell survival or recovery of sensory or motor function. Together, these experiments show that hypoxia-related preconditioning is ineffective at augmenting either cell survival or the functional outcomes of SC-SCI transplants. They also reveal that the benefits of hypoxia-related adaptations induced by preconditioning for cell transplant therapies are not universal.


Assuntos
Traumatismos da Medula Espinal , Ratos , Animais , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/metabolismo , Hipóxia , Células de Schwann/metabolismo , Transplante de Células , Sobrevivência Celular
9.
Cancer Sci ; 114(3): 1086-1094, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36341512

RESUMO

5-Aminolevulinic acid (5-ALA) is an amino acid that can be metabolized into a photosensitizer, protoporphyrin IX (PpIX) selectively in a tumor cell, permitting minimally invasive photodynamic diagnosis/therapy. However, some malignant tumor cells have excess intracellular labile iron and facilitate the conversion of PpIX into heme, which compromises the therapeutic potency of 5-ALA. Here, we examined the potential of chelation of such unfavorable intratumoral labile iron in photodynamic therapy (PDT) with 5-ALA hydrochloride, using polymeric iron chelators that we recently developed. The polymeric iron chelator efficiently inactivated the intracellular labile iron in cultured cancer cells and importantly enhanced the accumulation of PpIX, thereby improving the cytotoxicity upon photoirradiation. Even in in vivo study with subcutaneous tumor models, the polymeric iron chelator augmented the intratumoral accumulation of PpIX and the PDT effect. This study suggests that our polymeric iron chelator could be a tool for boosting the effect of 5-ALA-induced PDT by modulating tumor microenvironment.


Assuntos
Ácido Aminolevulínico , Fotoquimioterapia , Humanos , Ácido Aminolevulínico/farmacologia , Fármacos Fotossensibilizantes/química , Quelantes de Ferro/farmacologia , Ferro , Polímeros , Protoporfirinas , Linhagem Celular Tumoral
10.
Chemistry ; 29(50): e202300364, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37541431

RESUMO

A series of new conjugates comprised from a small synthetic antimicrobial peptide (AMP) and a siderophore-type vector component was designed and tested for activity on P. aeruginosa PAO1 and several genetically modified strains. As AMP, the well-established arginine-tryptophane combination K(RW)3 (P1) was chosen with an added lysine for siderophore attachment. This peptide is easy to prepare, modify, and possesses good anti-bacterial activity. On the vector part, we examined several moieties: (i) the natural siderophore deferoxamine (DFO); (ii) bidentate iron chelators based on the hydroxamate building block (4 a-c) ; (iii) the non-siderophore chelators deferasirox (DFX) and deferiprone-carboxylate (DFP-COOH). All conjugates were prepared by solid phase synthesis techniques and fully characterized by HPLC and mass spectrometry (including HR-MS). 55 Fe uptake assays indicate a receptor-mediated uptake for 4 a-c, DFP-COOH and DFO, which is dependent on the outer membrane transporter FoxA in the case of DFO. All conjugates showed increased antibacterial activity against P. aeruginosa compared to the parent peptide P1 alone when investigated in iron-depleted medium. MIC values were as low as 2 µM (for P1-DFP) on wild type P. aeruginosa. The activity of P1-DFO and P1-DFP was even better on genetically mutated strains unable to produce siderophores (down to 0.5 µM). Although the DFX vector on its own was not able to transport iron inside the bacterial cell as shown by 55 Fe uptake studies, the P1-DFX conjugate had excellent antibacterial activity compared to P1 (2 µM, and as low as 0.25 µM on a receptor-deficient strain unable to produce siderophores), suggesting that the conjugates were indeed recognized and internalized by an (unknown) transporter. Control experiments with an equimolar mixture of P1 and DFX confirm that the observed activity is intrinsic to vectorization. This work thus demonstrates the power of linking small AMPs covalently to siderophores for a new class of Trojan Horse antibiotics, with P1-DFP and P1-DFX being the most potent conjugates.


Assuntos
Pseudomonas aeruginosa , Sideróforos , Sideróforos/química , Ferro/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Membrana Transportadoras , Peptídeos , Proteínas de Transporte
11.
Mol Pharm ; 20(2): 1285-1295, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36622899

RESUMO

Hereditary hemochromatosis (HH) is a non-transfusional genetic iron overload (IO) disease wherein patients are not able to regulate dietary iron absorption, which ultimately leads to excess cellular iron accumulation. Preventative measures for HH mainly include phlebotomy and asking patients to minimize dietary iron intake. To investigate alternative iron reduction strategies, we report on prophylactic non-absorbable polymer-deferoxamine (DFO) conjugates capable of chelating and reducing excessive gut uptake of dietary iron. Three different sizes of the conjugates (56 nm, 256 nm, and 7.4 µm) were prepared, and their physicochemical properties, transit times in the gut under fed/fasted conditions, acute safety, and efficacy at reducing iron absorption in a dietary iron-overload mouse model were investigated. The conjugates were synthesized through reverse phase water-in-oil (w/o) emulsions, followed by conjugation of DFO to the resulting polymer scaffolds. In vitro studies using Caco-2 transwell assays showed that the conjugates could not permeate across the monolayer, were poorly endocytosed, and did not induce cellular toxicity. In vivo mouse studies via oral gavage demonstrated that polymer-DFO conjugates remained in the gastrointestinal (GI) tract for up to 12 h and significantly prevented escalation of serum ferritin levels and excess liver iron accumulation. Ex vivo images of the duodenum suggest that nanometer-sized conjugates (56 and 246 nm) perform better at chelating dietary iron based on longer retention times (i.e., entrapment in the villi of the duodenum) and an overall slower transit from the GI tract compared to larger micron-sized (7.4 µm) conjugates. Overall, nanometer-sized polymer-DFO conjugates were orally non-absorbable, appeared safe, and were more efficacious at reducing dietary iron absorption when taken with non-heme containing food.


Assuntos
Desferroxamina , Sobrecarga de Ferro , Humanos , Camundongos , Animais , Desferroxamina/química , Ferro da Dieta , Polímeros/química , Células CACO-2 , Quelantes de Ferro/farmacologia , Ferro/química , Sobrecarga de Ferro/tratamento farmacológico
12.
Clin Exp Ophthalmol ; 51(3): 205-216, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36594241

RESUMO

Hypoxia-inducible factor (HIF) plays a critical role in the mechanisms that allow cells to adapt to various oxygen levels in the environment. Specifically, HIF-1⍺ has shown to be widely involved in cellular repair, survival, and energy metabolism. HIF-1⍺ has also been found in increased levels in cancer cells, highlighting the importance of balance in the hypoxic response. Promoting HIF-1⍺ activity as a potential therapy for degenerative diseases and inhibiting HIF-1⍺ as a therapy for pathologies with overactive cell proliferation are actively being explored. Digoxin and metformin, HIF-1⍺ inhibitors, and deferoxamine and ⍺-ketoglutarate analogues, HIF-1⍺ activators, are being studied for application in age-related macular degeneration, diabetic retinopathy, and retinitis pigmentosa. However, these same medications have retinal toxicities that must be assessed before implementation of therapeutic care. Herein, we highlight the duality of therapeutic and toxic potential of HIF-1⍺ that must be carefully assessed prior to its clinical application in retinal disorders.


Assuntos
Retinopatia Diabética , Doenças Retinianas , Retinose Pigmentar , Humanos , Retina/patologia , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/metabolismo , Retinopatia Diabética/metabolismo , Hipóxia/patologia , Retinose Pigmentar/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
13.
Ecotoxicol Environ Saf ; 266: 115543, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37827095

RESUMO

As the mechanism of paraquat (PQ) poisoning is still not fully elucidated, and no specific treatment has been developed in medical practice, the management of PQ poisoning continues to present a medical challenge. In this study, the objective was to investigate the early metabolic changes in serum metabolism and identify the key metabolic pathways involved in patients with PQ poisoning. Quantitative analysis was conducted to determine the relevant metabolites. Additionally, experiments were carried out in both plasma and cell to elucidate the mechanisms underlying metabolic disorder and cell death in PQ poisoning. The study found that polyunsaturated fatty acids (PUFAs) and their metabolites, such as arachidonic acid (AA) and hydroxy eicosatetraenoic acids (HETEs), were significantly increased by non-enzymatic oxidative reaction. Reactive oxygen species (ROS) production increased rapidly at 2 h after PQ poisoning, followed by an increase in PUFAs at 12 h, and intracellular glutathione, cysteine (Cys), and Fe2+ at 24 h. However, at 36 h later, intracellular glutathione and Cys decreased, HETEs increased, and the expression of SLC7A11 and glutathione peroxidase 4 (GPX4) decreased. Ultrastructural examination revealed the absence of mitochondrial cristae. Deferoxamine was found to alleviate lipid oxidation, and increase the viability of PQ toxic cells in the low dose. In conclusion, unsaturated fatty acids metabolism was the key metabolic pathways in PQ poisoning. PQ caused cell death through the induction of ferroptosis. Inhibition of ferroptosis could be a novel strategy for the treatment of PQ poisoning.


Assuntos
Ferroptose , Paraquat , Humanos , Paraquat/toxicidade , Metabolismo dos Lipídeos , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo
14.
J Oral Rehabil ; 50(3): 234-242, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36588468

RESUMO

BACKGROUND: The effect of functional orthopaedic treatment for mandibular deficiency relies on mandibular advancement (MA)-induced condylar new bone formation. However, this is not easy to achieve, especially in non-growing patients. Therefore, how to obtain reliable MA-induced condylar osteogenesis is a subject much worthy of study. OBJECTIVE: To investigate whether deferoxamine mesylate (DFM) enhances MA-induced condylar osteogenesis in middle-aged mice. METHODS: Forty 30-week-old male C57BL/6J mice were randomly divided into 4 groups: the control (Ctrl), DFM, MA + Ctrl and MA + DFM groups. After a 4-week experimental period, femurs, tibias and condyles were collected for morphological, micro-computed tomography and histological evaluation. RESULTS: For long bones, DFM reversed osteoporosis in middle-aged mice by promoting H-type angiogenesis. For mandibular condyles, MA promoted condylar osteogenesis in middle-aged mice, thereby allowing the mandible to achieve a stable protruding position. In addition, DFM enhanced the volume and quality of MA-induced condylar new bone formation. Furthermore, histological analysis revealed that DFM enhanced MA-induced condylar subchondral ossification. Mechanistically, it was confirmed that DFM increased the number of H-type vessels and their coupled Osterix+ osteoprogenitors by upregulating the hypoxia-inducible factor (HIF)-1α signalling pathway, thereby enhancing MA-induced condylar osteogenesis. CONCLUSION: Applying DFM to enhance MA-induced condylar osteogenesis through H-type angiogenesis is expected to be an effective strategy to achieve favourable functional orthopaedic treatment effectiveness in non-growing patients.


Assuntos
Avanço Mandibular , Côndilo Mandibular , Masculino , Camundongos , Animais , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Osteogênese/fisiologia , Desferroxamina/farmacologia , Microtomografia por Raio-X , Camundongos Endogâmicos C57BL
15.
Int J Mol Sci ; 24(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36983075

RESUMO

Small extracellular vesicles (sEVs) derived from mesenchymal stem cells (MSCs) have attracted growing interest as a possible novel therapeutic agent for the management of different cardiovascular diseases (CVDs). Hypoxia significantly enhances the secretion of angiogenic mediators from MSCs as well as sEVs. The iron-chelating deferoxamine mesylate (DFO) is a stabilizer of hypoxia-inducible factor 1 and consequently used as a substitute for environmental hypoxia. The improved regenerative potential of DFO-treated MSCs has been attributed to the increased release of angiogenic factors, but whether this effect is also mediated by the secreted sEVs has not yet been investigated. In this study, we treated adipose-derived stem cells (ASCs) with a nontoxic dose of DFO to harvest sEVs (DFO-sEVs). Human umbilical vein endothelial cells (HUVECs) treated with DFO-sEVs underwent mRNA sequencing and miRNA profiling of sEV cargo (HUVEC-sEVs). The transcriptomes revealed the upregulation of mitochondrial genes linked to oxidative phosphorylation. Functional enrichment analysis on miRNAs of HUVEC-sEVs showed a connection with the signaling pathways of cell proliferation and angiogenesis. In conclusion, mesenchymal cells treated with DFO release sEVs that induce in the recipient endothelial cells molecular pathways and biological processes strongly linked to proliferation and angiogenesis.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Humanos , Células Cultivadas , Desferroxamina/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Quelantes de Ferro/farmacologia , Vesículas Extracelulares/metabolismo
16.
Medicina (Kaunas) ; 59(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36984454

RESUMO

Current primary intracerebral hemorrhage (ICH) treatments focus on limiting hematoma volume by lowering blood pressure, reversing anticoagulation, or hematoma evacuation. Nevertheless, there is no effective strategy to protect the brain from secondary injury due to ICH. Excess heme and iron as by-products of lysing clots in ICH might contribute to this secondary injury by triggering perihematomal edema. We present a clinical situation of an ICH case where iron-chelating therapy might be beneficial, as supported by scientific evidence. We looked through four databases (Pubmed, Cochrane, Embase, and Google Scholar) to find studies assessing the efficacy of iron-chelating therapy in ICH patients. Validity, importance, and applicability (VIA) of the included articles were appraised using worksheets from the Oxford Centre for Evidence-Based Medicine. Two out of five eligible studies were valid, important, and applicable to our patient. Both studies showed the positive effects of iron-chelating therapy on neurological outcome, as measured by National Institutes of Health Stroke Scale (NIHSS) score and modified Rankin Score (mRS). The beneficial effects of deferoxamine were demonstrated within the moderate volume (10-30 mL) subgroup, with a positive relative risk reduction (RRR) and low number needed to treat (six persons). Based on our appraisal, we considered iron-chelating therapy as an additional therapy for ICH patients, given its benefits and adverse effects. More specific studies using a larger sample size, focusing on moderate-volume ICH, and using standardized neurological outcomes are encouraged.


Assuntos
Hemorragia Cerebral , Quelantes de Ferro , Estados Unidos , Humanos , Quelantes de Ferro/uso terapêutico , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Encéfalo , Ferro/uso terapêutico , Hematoma
17.
Medicina (Kaunas) ; 59(7)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37476546

RESUMO

Colonic inflammatory bowel disease (IBD) encompasses ulcerative colitis (UC) and Crohn's colitis (CC). Patients with IBD are at increased risk for colitis-associated colorectal cancer (CACRC) compared to the general population. CACRC is preceded by IBD, characterized by highly heterogenous, pharmacologically incurable, pertinacious, worsening, and immune-mediated inflammatory pathologies of the colon and rectum. The molecular and immunological basis of CACRC is highly correlated with the duration and severity of inflammation, which is influenced by the exogenous free hemoglobin alpha chain (HbαC), a byproduct of infiltrating immune cells; extravasated erythrocytes; and macrophage erythrophagocytosis. The exogenous free HbαC prompts oxygen free radical-arbitrated DNA damage (DNAD) through increased cellular reactive oxygen species (ROS), which is exacerbated by decreased tissue antioxidant defenses. Mitigation of the Fenton Reaction via pharmaceutical therapy would attenuate ROS, promote apoptosis and DNAD repair, and subsequently prevent the incidence of CACRC. Three pharmaceutical options that attenuate hemoglobin toxicity include haptoglobin, deferoxamine, and flavonoids (vitamins C/E). Haptoglobin's clearance rate from plasma is inversely correlated with its size; the smaller the size, the faster the clearance. Thus, the administration of Hp1-1 may prove to be beneficial. Further, deferoxamine's hydrophilic structure limits its ability to cross cell membranes. Finally, the effectiveness of flavonoids, natural herb antioxidants, is associated with the high reactivity of hydroxyl substituents. Multiple analyses are currently underway to assess the clinical context of CACRC and outline the molecular basis of HbαC-induced ROS pathogenesis by exposing colonocytes and/or colonoids to HbαC. The molecular immunopathogenesis pathways of CACRC herein reviewed are broadly still not well understood. Therefore, this timely review outlines the molecular and immunological basis of disease pathogenesis and pharmaceutical intervention as a protective measure for CACRC.


Assuntos
Neoplasias Colorretais , Doenças Inflamatórias Intestinais , Linfo-Histiocitose Hemofagocítica , Humanos , Antioxidantes , Desferroxamina/uso terapêutico , Eritrócitos/metabolismo , Eritrócitos/patologia , Haptoglobinas/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/uso terapêutico
18.
Stroke ; 53(4): 1149-1156, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34789008

RESUMO

BACKGROUND: Hematoma volume (HV) is a powerful determinant of outcome after intracerebral hemorrhage. We examined whether the effect of the iron chelator, deferoxamine, on functional outcome varied depending on HV in the i-DEF trial (Intracerebral Hemorrhage Deferoxamine). METHODS: A post hoc analysis of the i-DEF trial; participants were classified according to baseline HV (small <10 mL, moderate 10-30 mL, and large >30 mL). Favorable outcome was defined as a modified Rankin Scale score of 0-2 at day-180; secondarily at day-90. Logistic regression was used to evaluate the differential treatment effect according to HV. RESULTS: Two hundred ninety-one subjects were included in the as-treated analysis; 121 with small, 114 moderate, and 56 large HV. Day-180 modified Rankin Scale scores were available for 270/291 subjects (111 with small, 105 moderate, and 54 large HV). There was a differential effect of treatment according to HV on day-180 outcomes (P-for-interaction =0.0077); 50% (27/54) of deferoxamine-treated patients with moderate HV had favorable outcome compared with 25.5% (13/51) of placebo-treated subjects (adjusted odds ratio, 2.7 [95% CI, 1.13-6.27]; P=0.0258). Treatment effect was not significant for small (adjusted odds ratio, 1.37 [95% CI, 0.62-3.02]) or large (adjusted odds ratio, 0.12 [95% CI, 0.01-1.05]) HV. Results for day-90 outcomes were comparable (P-for-interaction =0.0617). Sensitivity analyses yielded similar results. CONCLUSIONS: Among patients with moderate HV, a greater proportion of deferoxamine- than placebo-treated patients achieved modified Rankin Scale score 0-2. The treatment effect was not significant for small or large HVs. These findings have important trial design and therapeutic implications. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02175225.


Assuntos
Desferroxamina , Hematoma , Humanos , Hemorragia Cerebral , Desferroxamina/uso terapêutico , Hematoma/tratamento farmacológico , Razão de Chances , Resultado do Tratamento
19.
Stroke ; 53(7): 2204-2210, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35306827

RESUMO

BACKGROUND: There are limited data on the trajectory of recovery and long-term functional outcomes after intracerebral hemorrhage (ICH). Most ICH trials have conventionally assessed outcomes at 3 months following the footsteps of ischemic stroke. The i-DEF trial (Intracerebral Hemorrhage Deferoxamine Trial) assessed modified Rankin Scale (mRS) longitudinally at prespecified time points from day 7 through the end of the 6-month follow-up period. We evaluated the trajectory of mRS among trial participants and examined the effect of deferoxamine on this trajectory. METHODS: We performed a post hoc analysis of the i-DEF trial, a multicenter, randomized, placebo-controlled, double-blind, futility-design, phase 2 clinical trial, based on the actual treatment received. Favorable outcome was defined as mRS score of 0-2. A generalized linear mixed model was used to evaluate the outcome trajectory over time, as well as whether the trajectory was altered by deferoxamine, after adjustments for randomization variables, presence of intraventricular hemorrhage, and ICH location. RESULTS: A total of 291 subjects were included in analysis (145 placebo and 146 deferoxamine). The proportion of patients with mRS score of 0-2 continually increased from day 7 to 180 in both groups (interaction P<0.0001 for time in main effects model), but treatment with deferoxamine favorably altered the trajectory (interaction P=0.0010). Between day 90 and 180, the deferoxamine group improved (P=0.0001), whereas there was not significant improvement in the placebo arm (P=0.3005). CONCLUSIONS: A large proportion of patients continue to improve up to 6 months after ICH. Future ICH trials should assess outcomes past 90 days for a minimum of 6 months. In i-DEF, treatment with deferoxamine seemed to accelerate and alter the trajectory of recovery as assessed by mRS. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02175225.


Assuntos
Hemorragia Cerebral , Desferroxamina , Humanos , Hemorragia Cerebral/terapia , Desferroxamina/uso terapêutico , Método Duplo-Cego , Futilidade Médica , Resultado do Tratamento
20.
J Neurochem ; 161(1): 69-83, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35124818

RESUMO

Endolysosomes are key regulators of iron metabolism and are central to iron trafficking and redox signaling. Iron homeostasis is linked to endolysosome acidity and inhibition of endolysosome acidity triggers iron dysregulation. Because of the physiological importance and pathological relevance of ferrous iron (Fe2+ ), we determined levels of Fe2+ specifically and quantitatively in endolysosomes as well as the effects of Fe2+ on endolysosome morphology, distribution patterns, and function. The fluorescence dye FeRhoNox-1 was specific for Fe2+ and localized to endolysosomes in U87MG astrocytoma cells and primary rat cortical neurons; in U87MG cells the endolysosome concentration of Fe2+ ([Fe2+ ]el ) was 50.4 µM in control cells, 73.6 µM in ferric ammonium citrate (FAC) treated cells, and 12.4 µM in cells treated with the iron chelator deferoxamine (DFO). Under control conditions, in primary rat cortical neurons, [Fe2+ ]el was 32.7 µM. Endolysosomes containing the highest levels of Fe2+ were located perinuclearly. Treatment of cells with FAC resulted in endolysosomes that were less acidic, increased in numbers and sizes, and located further from the nucleus; opposite effects were observed for treatments with DFO. Thus, FeRhoNox-1 is a useful probe for the study of endolysosome Fe2+ , and much more work is needed to understand better the physiological significance and pathological relevance of endolysosomes classified according to their heterogeneous iron content Cover Image for this issue: https://doi.org/10.1111/jnc.15396.


Assuntos
Ferro , Lisossomos , Animais , Endossomos/metabolismo , Compostos Férricos/metabolismo , Compostos Férricos/farmacologia , Ferro/metabolismo , Lisossomos/metabolismo , Neurônios/metabolismo , Ratos
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