Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.227
Filtrar
1.
J Mol Med (Berl) ; 102(9): 1163-1174, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39110182

RESUMO

Cisplatin is a chemotherapeutic agent widely used to treat solid tumors. However, it can also be highly ototoxic, resulting in high-frequency hearing loss. Cisplatin causes degeneration of hair cells (HCs) and spiral ganglion neurons (SGNs) in the inner ear, which are essential components of the hearing process and cannot be regenerated in mammals. As the affected cells primarily die by apoptosis, we tested several anti-apoptotic small molecules to protect these cells from drug-induced toxicity. We found that the general caspase inhibitor Emricasan could significantly counteract the toxic effects of cisplatin in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells, phoenix auditory cells, and primary SGNs. Importantly, the anti-cytotoxic effect in neuronal cells was even more pronounced than the effect of sodium thiosulfate (STS), which is currently the only approved prevention option for cisplatin-induced ototoxicity. Finally, we tested the protective effect of Emricasan treatment in the context of another ototoxic drug, i.e., the aminoglycoside antibiotic neomycin, and again found a significant increase in cell viability when the cultures were co-treated with Emricasan. These results suggest a promising strategy to prevent ototoxicity in patients by temporarily blocking the apoptotic pathway when applying cisplatin or aminoglycoside antibiotics. KEY MESSAGES: Anti-apoptotic small molecules can reduce cisplatin-induced toxicity. Emricasan can effectively exert its anti-apoptotic effect on cochlear cells. Strong protection from cisplatin- and neomycin-induced cytotoxicity with Emricasan. Sodium thiosulfate and Emricasan provide similar protective effects to cisplatin-treated cells. Emricasan is more potent than sodium thiosulfate in reducing neomycin-induced cytotoxicity.


Assuntos
Inibidores de Caspase , Cisplatino , Neomicina , Cisplatino/efeitos adversos , Cisplatino/toxicidade , Cisplatino/farmacologia , Animais , Neomicina/farmacologia , Neomicina/toxicidade , Inibidores de Caspase/farmacologia , Camundongos , Apoptose/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Cóclea/citologia , Sobrevivência Celular/efeitos dos fármacos , Células Ciliadas Auditivas/efeitos dos fármacos , Gânglio Espiral da Cóclea/efeitos dos fármacos , Ototoxicidade/etiologia , Ototoxicidade/prevenção & controle , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Linhagem Celular , Células Cultivadas
2.
Nutrients ; 16(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39203853

RESUMO

Sensorineural hearing loss (SNHL), characterized by damage to the inner ear or auditory nerve, is a prevalent auditory disorder. This study explores the potential of Castanopsis echinocarpa (CAE) as a therapeutic agent for SNHL. In vivo experiments were conducted using zebrafish and mouse models. Zebrafish with neomycin-induced ototoxicity were treated with CAE, resulting in otic hair cell protection with an EC50 of 0.49 µg/mL and a therapeutic index of 1020. CAE treatment improved auditory function and protected cochlear sensory cells in a mouse model after noise-induced hearing loss (NIHL). RNA sequencing of NIHL mouse cochleae revealed that CAE up-regulates genes involved in neurotransmitter synthesis, secretion, transport, and neuronal survival. Real-time qPCR validation showed that NIHL decreased the mRNA expression of genes related to neuronal function, such as Gabra1, Gad1, Slc32a1, CaMK2b, CaMKIV, and Slc17a7, while the CAE treatment significantly elevated these levels. In conclusion, our findings provide strong evidence that CAE protects against hearing loss by promoting sensory cell protection and enhancing the expression of genes critical for neuronal function and survival.


Assuntos
Regulação da Expressão Gênica , Perda Auditiva Neurossensorial , Extratos Vegetais , Peixe-Zebra , Animais , Perda Auditiva Neurossensorial/genética , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/induzido quimicamente , Camundongos , Extratos Vegetais/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Modelos Animais de Doenças , Perda Auditiva Provocada por Ruído/tratamento farmacológico , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neomicina/farmacologia , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/metabolismo , Cóclea/efeitos dos fármacos , Cóclea/metabolismo , Ototoxicidade/etiologia , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo
3.
Nat Cardiovasc Res ; 3(3): 372-388, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39183959

RESUMO

Targeting Meis1 and Hoxb13 transcriptional activity could be a viable therapeutic strategy for heart regeneration. In this study, we performd an in silico screening to identify FDA-approved drugs that can inhibit Meis1 and Hoxb13 transcriptional activity based on the resolved crystal structure of Meis1 and Hoxb13 bound to DNA. Paromomycin (Paro) and neomycin (Neo) induced proliferation of neonatal rat ventricular myocytes in vitro and displayed dose-dependent inhibition of Meis1 and Hoxb13 transcriptional activity by luciferase assay and disruption of DNA binding by electromobility shift assay. X-ray crystal structure revealed that both Paro and Neo bind to Meis1 near the Hoxb13-interacting domain. Administration of Paro-Neo combination in adult mice and in pigs after cardiac ischemia/reperfusion injury induced cardiomyocyte proliferation, improved left ventricular systolic function and decreased scar formation. Collectively, we identified FDA-approved drugs with therapeutic potential for induction of heart regeneration in mammals.


Assuntos
Proliferação de Células , Proteínas de Homeodomínio , Proteína Meis1 , Miócitos Cardíacos , Regeneração , Animais , Regeneração/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Proliferação de Células/efeitos dos fármacos , Proteína Meis1/metabolismo , Proteína Meis1/genética , Neomicina/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Modelos Animais de Doenças , Aprovação de Drogas , Camundongos , Função Ventricular Esquerda/efeitos dos fármacos , United States Food and Drug Administration , Ratos , Estados Unidos , Cristalografia por Raios X , Masculino , Camundongos Endogâmicos C57BL , Suínos , Células Cultivadas , Transcrição Gênica/efeitos dos fármacos
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124686, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38950479

RESUMO

Neomycin sulfate (NEO) is a kind of aminoglycoside antibiotics. Because of its strong ototoxicity, nephrotoxicity and other side effects, its content in the body should be strictly monitored during use. In this paper, a rapid colorimetric detection method for NEO based on ultrasmall polyvinylpyrrolidone modified gold nanoparticles (PVP/Au NPs) with peroxidase-like activity was developed. Firstly, ultra small PVP/Au NPs with weak peroxidase-like activity were synthetized. When they were mixed with NEO, strong hydrogen bonds were formed between NEO and PVP, resulting in the aggregation of PVP/Au NPs, and the aggregated PVP/Au NPs showed stronger peroxidase-like activity. Therefore, rapid colorimetric detection of NEO was achieved by utilizing the enhanced peroxidase-like activity mechanism caused by the aggregation of ultra small PVP/Au NPs. The naked eye detection limit of this method is 50 nM. Within the range of 1 nM-300 nM, there was a good linear relationship between NEO concentration and the change in absorbance intensity of PVP/Au NPs-H2O2-TMB solution at 652 nm, with the regression curve of y = 0.0045x + 0.0525 (R2 = 0.998), and the detection limit is 1 nM. In addition, this method was successfully applied to the detection of NEO in mouse serum. The recoveries were 104.4 % -107.6 % compared with HPLC assay results, indicating that this method for NEO detection based on PVP/Au NPs has great potential in actual detection of NEO in serum.


Assuntos
Colorimetria , Ouro , Limite de Detecção , Nanopartículas Metálicas , Neomicina , Ouro/química , Colorimetria/métodos , Nanopartículas Metálicas/química , Animais , Neomicina/sangue , Neomicina/análise , Povidona/química , Camundongos , Peroxidase/metabolismo , Peroxidase/química , Peróxido de Hidrogênio/química
5.
Biomaterials ; 311: 122665, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38875882

RESUMO

Deafness mainly results from irreversible impairment of hair cells (HCs), which may relate to oxidative stress, yet therapeutical solutions is lacked due to limited understanding on the exact molecular mechanism. Herein, mimicking the molecular structure of natural enzymes, a palladium (Pd) single-atom nanozyme (SAN) was fabricated, exhibiting superoxide dismutase and catalase activity, transforming reactive oxygen species (ROS) into O2 and H2O. We examined the involvement of Pd in neomycin-induced HCs loss in vitro and in vivo over zebrafish. Our results revealed that neomycin treatment induced apoptosis in HCs, resulting in substantial of ROS elevation in HEI-OC1 cells, decrease in mitochondrial membrane potential, and increase in lipid peroxidation and iron accumulation, ultimately leading to iron-mediated cell death. Noteworthy, Pd SAN treatment exhibited significant protective effects against HCs damage and impaired HCs function in zebrafish by inhibiting ferroptosis. Furthermore, the application of iron death inducer RSL3 resulted in notable exacerbation of neomycin-induced harm, which was mitigated by Pd administration. Our investigation demonstrates that antioxidants is promising for inhibiting ferroptosis and repairing of mitochondrial function in HCs and the enzyme-mimic SAN provides a good strategy for designing drugs alleviating neomycin-induced ototoxicity.


Assuntos
Ferroptose , Células Ciliadas Auditivas , Perda Auditiva , Neomicina , Paládio , Espécies Reativas de Oxigênio , Peixe-Zebra , Animais , Neomicina/farmacologia , Paládio/química , Paládio/farmacologia , Ferroptose/efeitos dos fármacos , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , Perda Auditiva/tratamento farmacológico , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Apoptose/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
6.
Virulence ; 15(1): 2367647, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38884466

RESUMO

The global surge in multidrug-resistant bacteria owing to antibiotic misuse and overuse poses considerable risks to human and animal health. With existing antibiotics losing their effectiveness and the protracted process of developing new antibiotics, urgent alternatives are imperative to curb disease spread. Notably, improving the bactericidal effect of antibiotics by using non-antibiotic substances has emerged as a viable strategy. Although reduced nicotinamide adenine dinucleotide (NADH) may play a crucial role in regulating bacterial resistance, studies examining how the change of metabolic profile and bacterial resistance following by exogenous administration are scarce. Therefore, this study aimed to elucidate the metabolic changes that occur in Edwardsiella tarda (E. tarda), which exhibits resistance to various antibiotics, following the exogenous addition of NADH using metabolomics. The effects of these alterations on the bactericidal activity of neomycin were investigated. NADH enhanced the effectiveness of aminoglycoside antibiotics against E. tarda ATCC15947, achieving bacterial eradication at low doses. Metabolomic analysis revealed that NADH reprogrammed the ATCC15947 metabolic profile by promoting purine metabolism and energy metabolism, yielding increased adenosine triphosphate (ATP) levels. Increased ATP levels played a crucial role in enhancing the bactericidal effects of neomycin. Moreover, exogenous NADH promoted the bactericidal efficacy of tetracyclines and chloramphenicols. NADH in combination with neomycin was effective against other clinically resistant bacteria, including Aeromonas hydrophila, Vibrio parahaemolyticus, methicillin-resistant Staphylococcus aureus, and Listeria monocytogenes. These results may facilitate the development of effective approaches for preventing and managing E. tarda-induced infections and multidrug resistance in aquaculture and clinical settings.


Assuntos
Aminoglicosídeos , Antibacterianos , Edwardsiella tarda , NAD , Edwardsiella tarda/efeitos dos fármacos , Antibacterianos/farmacologia , NAD/metabolismo , Aminoglicosídeos/farmacologia , Animais , Doenças dos Peixes/microbiologia , Doenças dos Peixes/tratamento farmacológico , Testes de Sensibilidade Microbiana , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Trifosfato de Adenosina/metabolismo , Neomicina/farmacologia , Sinergismo Farmacológico , Metabolômica , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos
7.
Chempluschem ; 89(8): e202400178, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38758051

RESUMO

The ongoing search for small molecule drugs that target ribonucleic acids (RNA) is complicated by a limited understanding of the principles that govern RNA-small molecule interactions. Here we have used stoichiometry-resolved native top-down mass spectrometry (MS) to study the binding of neomycin B to small model hairpin RNAs, an unstructured RNA, and a viral RNA construct. For 15-22 nt model RNAs with hairpin structure, we found that neomycin B binding to hairpin loops relies on interactions with both the nucleobases and the 2'-OH groups, and that a simple 5' or 3' overhang can introduce an additional binding motif. For a 47 nt RNA construct derived from stem IA of the human immunodeficiency virus 1 (HIV-1) rev response element (RRE) RNA, native top-down MS identified four different binding motifs, of which the purine-rich internal loop showed the highest affinity for neomycin B. Stoichiometry-resolved binding site mapping by native top-down MS allows for a new perspective on binding specificity, and has the potential to reveal unexpected principles of small molecule binding to RNA.


Assuntos
Framicetina , Espectrometria de Massas , Framicetina/química , Sítios de Ligação , Conformação de Ácido Nucleico , RNA/química , RNA/metabolismo , RNA Viral/química , RNA Viral/metabolismo , Motivos de Ligação ao RNA , HIV-1/química , Neomicina/química
8.
PeerJ ; 12: e17349, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784394

RESUMO

Background: Antibiotics are commonly used for controlling microbial growth in diseased organisms. However, antibiotic treatments during early developmental stages can have negative impacts on development and physiology that could offset the positive effects of reducing or eliminating pathogens. Similarly, antibiotics can shift the microbial community due to differential effectiveness on resistant and susceptible bacteria. Though antibiotic application does not typically result in mortality of marine invertebrates, little is known about the developmental and transcriptional effects. These sublethal effects could reduce the fitness of the host organism and lead to negative changes after removal of the antibiotics. Here, we quantify the impact of antibiotic treatment on development, gene expression, and the culturable bacterial community of a model cnidarian, Nematostella vectensis. Methods: Ampicillin, streptomycin, rifampicin, and neomycin were compared individually at two concentrations, 50 and 200 µg mL-1, and in combination at 50 µg mL-1 each, to assess their impact on N. vectensis. First, we determined the impact antibiotics have on larval development. Next Amplicon 16S rDNA gene sequencing was used to compare the culturable bacteria that persist after antibiotic treatment to determine how these treatments may differentially select against the native microbiome. Lastly, we determined how acute (3-day) and chronic (8-day) antibiotic treatments impact gene expression of adult anemones. Results: Under most exposures, the time of larval settlement extended as the concentration of antibiotics increased and had the longest delay of 3 days in the combination treatment. Culturable bacteria persisted through a majority of exposures where we identified 359 amplicon sequence variants (ASVs). The largest proportion of bacteria belonged to Gammaproteobacteria, and the most common ASVs were identified as Microbacterium and Vibrio. The acute antibiotic exposure resulted in differential expression of genes related to epigenetic mechanisms and neural processes, while constant application resulted in upregulation of chaperones and downregulation of mitochondrial genes when compared to controls. Gene Ontology analyses identified overall depletion of terms related to development and metabolism in both antibiotic treatments. Discussion: Antibiotics resulted in a significant increase to settlement time of N. vectensis larvae. Culturable bacterial species after antibiotic treatments were taxonomically diverse. Additionally, the transcriptional effects of antibiotics, and after their removal result in significant differences in gene expression that may impact the physiology of the anemone, which may include removal of bacterial signaling on anemone gene expression. Our research suggests that impacts of antibiotics beyond the reduction of bacteria may be important to consider when they are applied to aquatic invertebrates including reef building corals.


Assuntos
Antibacterianos , Larva , Anêmonas-do-Mar , Animais , Antibacterianos/farmacologia , Anêmonas-do-Mar/genética , Anêmonas-do-Mar/efeitos dos fármacos , Larva/microbiologia , Larva/efeitos dos fármacos , Larva/genética , Ampicilina/farmacologia , Neomicina/farmacologia , Estreptomicina/farmacologia , Rifampina/farmacologia , Expressão Gênica/efeitos dos fármacos
9.
Int J Biol Macromol ; 270(Pt 1): 132297, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744365

RESUMO

3D multifunctional scaffold has been designed based on Cs/SA/NS/NPHA. Nanoparticles hydroxyapatite (NPHA) was prepared via precipitation method of sodium dihydrogen phosphate in presence calcium chloride. Different ratios of Chitosan (CS)/Sodium Alginate (SA) were used to prepare Cs/SA scaffolds in presence of CaCl2 as a cross linker. NPHA was incorporated in CS/SA scaffold and neomycin sulfate (NS) was added as an antimicrobial agent. The structure and surface morphology of the scaffolds were investigated via infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and thermal gravimetric analysis (TGA) techniques. Additionally, Antimicrobial activity of the scaffold has evaluated against Gram- negative and Gram- positive bacteria. The result showed promising antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Furthermore, cytotoxicity against MG63 osteosarcoma cell and fibroblast normal cell line has investigated. The result showed anti-proliferative against MG63. DFT calculations and molecular docking were used to study the reactivity of the compounds. The results exhibited that Cs/SA/NS/NPHA is potent expected to be used in bone tissue regeneration.


Assuntos
Alginatos , Anti-Infecciosos , Proliferação de Células , Quitosana , Durapatita , Simulação de Acoplamento Molecular , Neomicina , Alicerces Teciduais , Quitosana/química , Quitosana/farmacologia , Durapatita/química , Alginatos/química , Alginatos/farmacologia , Neomicina/farmacologia , Neomicina/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Humanos , Proliferação de Células/efeitos dos fármacos , Alicerces Teciduais/química , Teoria da Densidade Funcional , Testes de Sensibilidade Microbiana
10.
Int J Biol Macromol ; 271(Pt 1): 132577, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795887

RESUMO

Staphylococcus aureus is a pathogen widely involved in wound infection due to its ability to release several virulence factors that impair the skin healing process, as well as its mechanism of drug resistance. Herein, sodium alginate and chitosan were combined to produce a hydrogel for topical delivery of neomycin to combat S. aureus associated with skin complications. The hydrogel was formulated by combining sodium alginate (50 mg/mL) and chitosan (50 mg/mL) solutions in a ratio of 9:1 (HBase). Neomycin was added to HBase to achieve a concentration of 0.4 mg/mL (HNeo). The incorporation of neomycin into the product was confirmed by scanning electron microscopy, FTIR and TGA analysis. The hydrogels produced are homogeneous, have a high swelling capacity, and show biocompatibility using erythrocytes and fibroblasts as models. The formulations showed physicochemical and pharmacological stability for 60 days at 4 ± 2 °C. HNeo totally inhibited the growth of S. aureus after 4 h. The antimicrobial effects were confirmed using ex vivo (porcine skin) and in vivo (murine) wound infection models. Furthermore, the HNeo-treated mice showed lower severity scores than those treated with HBase. Taken together, the obtained results present a new low-cost bioproduct with promising applications in treating infected wounds.


Assuntos
Alginatos , Antibacterianos , Quitosana , Hidrogéis , Neomicina , Staphylococcus aureus , Quitosana/química , Quitosana/farmacologia , Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Camundongos , Neomicina/farmacologia , Neomicina/química , Neomicina/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/patologia , Portadores de Fármacos/química , Pele/efeitos dos fármacos , Pele/microbiologia
12.
Arch Toxicol ; 98(6): 1827-1842, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563869

RESUMO

Aminoglycosides are commonly used antibiotics for treatment of gram-negative bacterial infections, however, they might act on inner ear, leading to hair-cell death and hearing loss. Currently, there is no targeted therapy for aminoglycoside ototoxicity, since the underlying mechanisms of aminoglycoside-induced hearing impairments are not fully defined. This study aimed to investigate whether the calcium channel blocker verapamil and changes in intracellular & extracellular calcium could ameliorate aminoglycoside-induced ototoxicity in zebrafish. The present findings showed that a significant decreased number of neuromasts in the lateral lines of zebrafish larvae at 5 days' post fertilization after neomycin (20 µM) and gentamicin (20 mg/mL) exposure, which was prevented by verapamil. Moreover, verapamil (10-100 µM) attenuated aminoglycoside-induced toxic response in different external calcium concentrations (33-3300 µM). The increasing extracellular calcium reduced hair cell loss from aminoglycoside exposure, while lower calcium facilitated hair cell death. In contrast, calcium channel activator Bay K8644 (20 µM) enhanced aminoglycoside-induced ototoxicity and reversed the protective action of higher external calcium on hair cell loss. However, neomycin-elicited hair cell death was not altered by caffeine, ryanodine receptor (RyR) agonist, and RyR antagonists, including thapsigargin, ryanodine, and ruthenium red. The uptake of neomycin into hair cells was attenuated by verapamil and under high external calcium concentration. Consistently, the production of reactive oxygen species (ROS) in neuromasts exposed to neomycin was also reduced by verapamil and high external calcium. Significantly, zebrafish larvae when exposed to neomycin exhibited decreased swimming distances in reaction to droplet stimulus when compared to the control group. Verapamil and elevated external calcium effectively protected the impaired swimming ability of zebrafish larvae induced by neomycin. These data imply that prevention of hair cell damage correlated with swimming behavior against aminoglycoside ototoxicity by verapamil and higher external calcium might be associated with inhibition of excessive ROS production and aminoglycoside uptake through cation channels. These findings indicate that calcium channel blocker and higher external calcium could be applied to protect aminoglycoside-induced listening impairments.


Assuntos
Antibacterianos , Bloqueadores dos Canais de Cálcio , Cálcio , Gentamicinas , Células Ciliadas Auditivas , Neomicina , Verapamil , Peixe-Zebra , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Verapamil/farmacologia , Neomicina/toxicidade , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/metabolismo , Gentamicinas/toxicidade , Antibacterianos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Ototoxicidade/prevenção & controle , Aminoglicosídeos/toxicidade , Sistema da Linha Lateral/efeitos dos fármacos , Larva/efeitos dos fármacos , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle
13.
Proc Natl Acad Sci U S A ; 121(15): e2317197121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38579011

RESUMO

Riboswitches are messenger RNA (mRNA) fragments binding specific small molecules to regulate gene expression. A synthetic N1 riboswitch, inserted into yeast mRNA controls the translation of a reporter gene in response to neomycin. However, its regulatory activity is sensitive to single-point RNA mutations, even those distant from the neomycin binding site. While the association paths of neomycin to N1 and its variants remain unknown, recent fluorescence kinetic experiments indicate a two-step process driven by conformational selection. This raises the question of which step is affected by mutations. To address this, we performed all-atom two-dimensional replica-exchange molecular dynamics simulations for N1 and U14C, U14C[Formula: see text], U15A, and A17G mutants, ensuring extensive conformational sampling of both RNA and neomycin. The obtained neomycin association and binding paths, along with multidimensional free-energy profiles, revealed a two-step binding mechanism, consisting of conformational selection and induced fit. Neomycin binds to a preformed N1 conformation upon identifying a stable upper stem and U-turn motif in the riboswitch hairpin. However, the positioning of neomycin in the binding site occurs at different RNA-neomycin distances for each mutant, which may explain their different regulatory activities. The subsequent induced fit arises from the interactions of the neomycin's N3 amino group with RNA, causing the G9 backbone to rearrange. In the A17G mutant, the critical C6-A17/G17 stacking forms at a closer RNA-neomycin distance compared to N1. These findings together with estimated binding free energies coincide with experiments and elucidate why the A17G mutation decreases and U15A enhances N1 activity in response to neomycin.


Assuntos
Neomicina , Riboswitch , Neomicina/metabolismo , Neomicina/farmacologia , Simulação de Dinâmica Molecular , Riboswitch/genética , Mutação , Conformação Molecular , Conformação de Ácido Nucleico , Ligantes
14.
Proc Natl Acad Sci U S A ; 121(18): e2319566121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38648490

RESUMO

Respiratory virus infections in humans cause a broad-spectrum of diseases that result in substantial morbidity and mortality annually worldwide. To reduce the global burden of respiratory viral diseases, preventative and therapeutic interventions that are accessible and effective are urgently needed, especially in countries that are disproportionately affected. Repurposing generic medicine has the potential to bring new treatments for infectious diseases to patients efficiently and equitably. In this study, we found that intranasal delivery of neomycin, a generic aminoglycoside antibiotic, induces the expression of interferon-stimulated genes (ISGs) in the nasal mucosa that is independent of the commensal microbiota. Prophylactic or therapeutic administration of neomycin provided significant protection against upper respiratory infection and lethal disease in a mouse model of COVID-19. Furthermore, neomycin treatment protected Mx1 congenic mice from upper and lower respiratory infections with a highly virulent strain of influenza A virus. In Syrian hamsters, neomycin treatment potently mitigated contact transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In healthy humans, intranasal application of neomycin-containing Neosporin ointment was well tolerated and effective at inducing ISG expression in the nose in a subset of participants. These findings suggest that neomycin has the potential to be harnessed as a host-directed antiviral strategy for the prevention and treatment of respiratory viral infections.


Assuntos
Administração Intranasal , Antivirais , Neomicina , SARS-CoV-2 , Animais , Neomicina/farmacologia , Neomicina/administração & dosagem , Camundongos , Humanos , Antivirais/farmacologia , Antivirais/administração & dosagem , SARS-CoV-2/imunologia , SARS-CoV-2/efeitos dos fármacos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/virologia , Infecções Respiratórias/prevenção & controle , Mucosa Nasal/imunologia , Mucosa Nasal/virologia , Mucosa Nasal/efeitos dos fármacos , Modelos Animais de Doenças , Tratamento Farmacológico da COVID-19 , Mesocricetus , Feminino , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/imunologia
15.
JAMA Surg ; 159(6): 606-614, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38506889

RESUMO

Importance: Surgical site infections (SSIs)-especially anastomotic dehiscence-are major contributors to morbidity and mortality after rectal resection. The role of mechanical and oral antibiotics bowel preparation (MOABP) in preventing complications of rectal resection is currently disputed. Objective: To assess whether MOABP reduces overall complications and SSIs after elective rectal resection compared with mechanical bowel preparation (MBP) plus placebo. Design, Setting, and Participants: This multicenter, double-blind, placebo-controlled randomized clinical trial was conducted at 3 university hospitals in Finland between March 18, 2020, and October 10, 2022. Patients aged 18 years and older undergoing elective resection with primary anastomosis of a rectal tumor 15 cm or less from the anal verge on magnetic resonance imaging were eligible for inclusion. Outcomes were analyzed using a modified intention-to-treat principle, which included all patients who were randomly allocated to and underwent elective rectal resection with an anastomosis. Interventions: Patients were stratified according to tumor distance from the anal verge and neoadjuvant treatment given and randomized in a 1:1 ratio to receive MOABP with an oral regimen of neomycin and metronidazole (n = 277) or MBP plus matching placebo tablets (n = 288). All study medications were taken the day before surgery, and all patients received intravenous antibiotics approximately 30 minutes before surgery. Main Outcomes and Measures: The primary outcome was overall cumulative postoperative complications measured using the Comprehensive Complication Index. Key secondary outcomes were SSI and anastomotic dehiscence within 30 days after surgery. Results: In all, 565 patients were included in the analysis, with 288 in the MBP plus placebo group (median [IQR] age, 69 [62-74] years; 190 males [66.0%]) and 277 in the MOABP group (median [IQR] age, 70 [62-75] years; 158 males [57.0%]). Patients in the MOABP group experienced fewer overall postoperative complications (median [IQR] Comprehensive Complication Index, 0 [0-8.66] vs 8.66 [0-20.92]; Wilcoxon effect size, 0.146; P < .001), fewer SSIs (23 patients [8.3%] vs 48 patients [16.7%]; odds ratio, 0.45 [95% CI, 0.27-0.77]), and fewer anastomotic dehiscences (16 patients [5.8%] vs 39 patients [13.5%]; odds ratio, 0.39 [95% CI, 0.21-0.72]) compared with patients in the MBP plus placebo group. Conclusions and Relevance: Findings of this randomized clinical trial indicate that MOABP reduced overall postoperative complications as well as rates of SSIs and anastomotic dehiscences in patients undergoing elective rectal resection compared with MBP plus placebo. Based on these findings, MOABP should be considered as standard treatment in patients undergoing elective rectal resection. Trial Registration: ClinicalTrials.gov Identifier: NCT04281667.


Assuntos
Antibacterianos , Neoplasias Retais , Infecção da Ferida Cirúrgica , Humanos , Masculino , Feminino , Método Duplo-Cego , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Neoplasias Retais/cirurgia , Administração Oral , Antibioticoprofilaxia , Cuidados Pré-Operatórios/métodos , Neomicina/administração & dosagem , Neomicina/uso terapêutico , Catárticos/administração & dosagem , Metronidazol/administração & dosagem , Metronidazol/uso terapêutico , Protectomia/efeitos adversos , Reto/cirurgia , Deiscência da Ferida Operatória/prevenção & controle , Deiscência da Ferida Operatória/etiologia , Procedimentos Cirúrgicos Eletivos/efeitos adversos
16.
Int Immunol ; 36(7): 365-371, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38442194

RESUMO

The intestinal barrier consists of mucosal, epithelial, and immunological barriers and serves as a dynamic interface between the host and its environment. Disruption of the intestinal barrier integrity is a leading cause of various gastrointestinal diseases, such as inflammatory bowel disease. The homeostasis of the intestinal barrier is tightly regulated by crosstalk between gut microbes and the immune system; however, the implication of the immune system on the imbalance of gut microbes that disrupts barrier integrity remains to be fully elucidated. An inhibitory immunoglobulin-like receptor, Allergin-1, is expressed on mast cells and dendritic cells and inhibits Toll-like receptor (TLR)-2 and TLR-4 signaling in these cells. Since TLRs are major sensors of microbiota and are involved in local epithelial homeostasis, we investigated the role of Allergin-1 in maintaining intestinal homeostasis. Allergin-1-deficient (Milr1-/-) mice exhibited more severe dextran sulfate sodium (DSS)-induced colitis than did wild-type (WT) mice. Milr1-/- mice showed an enhanced intestinal permeability compared with WT mice even before DSS administration. Treatment of Milr1-/- mice with neomycin, but not ampicillin, restored intestinal barrier integrity. The 16S rRNA gene sequencing analysis demonstrated that Bifidobacterium pseudolongum was the dominant bacterium in Milr1-/- mice after treatment with ampicillin. Although the transfer of B. pseudolongum to germ-free WT mice had no effect on intestinal permeability, its transfer into ampicillin-treated WT mice enhanced intestinal permeability. These results demonstrated that Allergin-1 deficiency enhanced intestinal dysbiosis with expanded B. pseudolongum, which contributes to intestinal barrier dysfunction in collaboration with neomycin-sensitive and ampicillin-resistant microbiota.


Assuntos
Disbiose , Mucosa Intestinal , Camundongos Endogâmicos C57BL , Camundongos Knockout , Animais , Disbiose/imunologia , Camundongos , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo , Sulfato de Dextrana , Microbioma Gastrointestinal/imunologia , Colite/imunologia , Colite/microbiologia , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Neomicina/farmacologia , Permeabilidade
17.
Cell Prolif ; 57(8): e13633, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38528645

RESUMO

Hair cell (HC) damage is a leading cause of sensorineural hearing loss, and in mammals supporting cells (SCs) are unable to divide and regenerate HCs after birth spontaneously. Procollagen C-endopeptidase enhancer 2 (Pcolce2), which encodes a glycoprotein that acts as a functional procollagen C protease enhancer, was screened as a candidate regulator of SC plasticity in our previous study. In the current study, we used adeno-associated virus (AAV)-ie (a newly developed adeno-associated virus that targets SCs) to overexpress Pcolce2 in SCs. AAV-Pcolce2 facilitated SC re-entry into the cell cycle both in cultured cochlear organoids and in the postnatal cochlea. In the neomycin-damaged model, regenerated HCs were detected after overexpression of Pcolce2, and these were derived from SCs that had re-entered the cell cycle. These findings reveal that Pcolce2 may serve as a therapeutic target for the regeneration of HCs to treat hearing loss.


Assuntos
Animais Recém-Nascidos , Reprogramação Celular , Cóclea , Animais , Camundongos , Cóclea/metabolismo , Cóclea/citologia , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/citologia , Dependovirus/genética , Ciclo Celular , Camundongos Endogâmicos C57BL , Regeneração , Células Labirínticas de Suporte/metabolismo , Neomicina/farmacologia
18.
Sci Rep ; 14(1): 4163, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378700

RESUMO

Resistance against aminoglycosides is widespread in bacteria. This study aimed to identify genes that are important for growth of E. coli during aminoglycoside exposure, since such genes may be targeted to re-sensitize resistant E. coli to treatment. We constructed three transposon mutant libraries each containing > 230.000 mutants in E. coli MG1655 strains harboring streptomycin (aph(3″)-Ib/aph(6)-Id), gentamicin (aac(3)-IV), or neomycin (aph(3″)-Ia) resistance gene(s). Transposon Directed Insertion-site Sequencing (TraDIS), a combination of transposon mutagenesis and high-throughput sequencing, identified 56 genes which were deemed important for growth during streptomycin, 39 during gentamicin and 32 during neomycin exposure. Most of these fitness-genes were membrane-located (n = 55) and involved in either cell division, ATP-synthesis or stress response in the streptomycin and gentamicin exposed libraries, and enterobacterial common antigen biosynthesis or magnesium sensing/transport in the neomycin exposed library. For validation, eight selected fitness-genes/gene-clusters were deleted (minCDE, hflCK, clsA and cpxR associated with streptomycin and gentamicin resistance, and phoPQ, wecA, lpp and pal associated with neomycin resistance), and all mutants were shown to be growth attenuated upon exposure to the corresponding antibiotics. In summary, we identified genes that are advantageous in aminoglycoside-resistant E. coli during antibiotic stress. In addition, we increased the understanding of how aminoglycoside-resistant E. coli respond to antibiotic exposure.


Assuntos
Aminoglicosídeos , Antibacterianos , Antibacterianos/farmacologia , Aminoglicosídeos/farmacologia , Escherichia coli/genética , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Estreptomicina/farmacologia , Gentamicinas/farmacologia , Neomicina/farmacologia
19.
ACS Infect Dis ; 10(2): 527-540, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38294409

RESUMO

Gram-negative bacterial infections are difficult to manage as many antibiotics are ineffective owing to the presence of impermeable bacterial membranes. Polymicrobial infections pose a serious threat due to the inadequate efficacy of available antibiotics, thereby necessitating the administration of antibiotics at higher doses. Antibiotic adjuvants have emerged as a boon as they can augment the therapeutic potential of available antibiotics. However, the toxicity profile of antibiotic adjuvants is a major hurdle in clinical translation. Here, we report the design, synthesis, and biological activities of xanthone-derived molecules as potential antibiotic adjuvants. Our SAR studies witnessed that the p-dimethylamino pyridine-derivative of xanthone (X8) enhances the efficacy of neomycin (NEO) against Escherichia coli and Pseudomonas aeruginosa and causes a synergistic antimicrobial effect without any toxicity against mammalian cells. Biochemical studies suggest that the combination of X8 and NEO, apart from inhibiting protein synthesis, enhances the membrane permeability by binding to lipopolysaccharide. Notably, the combination of X8 and NEO can disrupt the monomicrobial and polymicrobial biofilms and show promising therapeutic potential against a murine wound infection model. Collectively, our results unveil the combination of X8 and NEO as a suitable adjuvant therapy for the inhibition of the Gram-negative bacterial infections.


Assuntos
Infecções por Bactérias Gram-Negativas , Xantonas , Animais , Camundongos , Antibacterianos/farmacologia , Biofilmes , Escherichia coli , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Mamíferos , Neomicina/farmacologia , Xantonas/farmacologia
20.
Altern Ther Health Med ; 30(8): 86-91, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38290457

RESUMO

Objective: Exploring the clinical efficacy of neomycin and sakubactria valsartan in the treatment of patients with chronic heart failure (CHF) and atrial fibrillation. This study investigates the potential benefits of combining neomycin with sakubactria valsartan, a medication with a background of demonstrated efficacy in cardiovascular conditions, to address the complex challenges presented by chronic heart failure and atrial fibrillation. Methods: Using a single-center clinical randomized trial, 111 patients with CHF complicated with atrial fibrillation who were treated in the cardiovascular department of Xingtai Third Hospital from June 2019 to March 2021 were randomly divided into two groups. In the control group, 56 patients received treatment with Western Medicine Foundation + Shakubatra valsartan. In the experimental group, consisting of 55 patients, the treatment was identical to the control group, with the additional administration of neomycin.. After 12 weeks of continuous treatment, the echocardiograms, electrocardiogram parameters, and Differences in changes in serum soluble growth stimulating gene 2 protein (sST2) and galactose agglutinin 3 (Gal-3), clinical efficacy, and incidence of adverse reactions. Results: Before treatment, no significant differences existed in LVEF, LVEDV, FS, and SV between the experimental and control groups (P > .05). Post-treatment, both groups exhibited significant improvements in these parameters, with the experimental group showing statistically higher values (P < .05).Similarly, pre-treatment comparisons of Pd, sST2, Gal-3, and NT-proBNP revealed no significant differences between the groups (P > .05). After treatment, both groups showed significant reductions, with the experimental group demonstrating lower values (P < .05).Clinical efficacy assessment post-treatment showed significant differences. The experimental group had a basic cure rate of 45.45%, a significant effective rate of 43.64%, and an effective rate of 10.91%, while the control group had rates of 28.57%, 48.21%, and 23.21%, respectively (P < .05).Adverse reactions occurred in 9 and 4 patients in the experimental and control groups, respectively. The severity was not significant, and treatment was uninterrupted (P > 0.05).The treatment improved heart function and reduced atrial fibrillation occurrences, holding clinical significance by potentially enhancing patients' quality of life and decreasing cardiovascular events. These results highlight the clinical significance of this treatment, which may help improve patients' quality of life and reduce the occurrence of cardiovascular events. Conclusion: The treatment of patients with CHF combined with atrial fibrillation using neomycin and sakubactria valsartan can more effectively improve their cardiac function and alleviate the condition of atrial fibrillation, which is worthy of clinical promotion and application. In actual clinical practice, physicians and healthcare providers may consider incorporating this treatment into their treatment regimens, especially for patients who need to improve heart function and reduce the risk of atrial fibrillation. Additionally, further research and clinical trials can further validate these findings to ensure their effectiveness and safety. These insights will help the medical community better understand how to apply this treatment to real patients and maximize its clinical effectiveness.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Valsartana , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Masculino , Feminino , Valsartana/uso terapêutico , Idoso , Pessoa de Meia-Idade , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/complicações , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Neomicina/uso terapêutico , Quimioterapia Combinada , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...