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1.
Molecules ; 28(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005371

RESUMO

The efflux systems are considered important mechanisms of bacterial resistance due to their ability to extrude various antibiotics. Several naturally occurring compounds, such as sesquiterpenes, have demonstrated antibacterial activity and the ability to inhibit efflux pumps in resistant strains. Therefore, the objective of this research was to analyze the antibacterial and inhibitory activity of the efflux systems NorA, Tet(K), MsrA, and MepA by sesquiterpenes nerolidol, farnesol, and α-bisabolol, used either individually or in liposomal nanoformulation, against multi-resistant Staphylococcus aureus strains. The methodology consisted of in vitro testing of the ability of sesquiterpenes to reduce the Minimum Inhibitory Concentration (MIC) and enhance the action of antibiotics and ethidium bromide (EtBr) in broth microdilution assays. The following strains were used: S. aureus 1199B carrying the NorA efflux pump, resistant to norfloxacin; IS-58 strain carrying Tet(K), resistant to tetracyclines; RN4220 carrying MsrA, conferring resistance to erythromycin. For the EtBr fluorescence measurement test, K2068 carrying MepA was used. It was observed the individual sesquiterpenes exhibited better antibacterial activity as well as efflux pump inhibition. Farnesol showed the lowest MIC of 16.5 µg/mL against the S. aureus RN4220 strain. Isolated nerolidol stood out for reducing the MIC of EtBr to 5 µg/mL in the 1199B strain, yielding better results than the positive control CCCP, indicating strong evidence of NorA inhibition. The liposome formulations did not show promising results, except for liposome/farnesol, which reduced the MIC of EtBr against 1199B and RN4220. Further research is needed to evaluate the mechanisms of action involved in the inhibition of resistance mechanisms by the tested compounds.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Sesquiterpenos , Farneseno Álcool/farmacologia , Staphylococcus aureus/metabolismo , Staphylococcus aureus Resistente à Meticilina/metabolismo , Lipossomos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Antibacterianos/farmacologia , Sesquiterpenos/farmacologia , Etídio/farmacologia , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/metabolismo
2.
Acta Biochim Pol ; 70(3): 599-600, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37677069

RESUMO

The natural Fisetin and its derivatives have been shown to have effective bioactivity and strong pharmacological profile, which is continuously drawing the interest of therapeutic applications to the development of new biomolecules against Breast cancer and Monkeypox, and Marburg viral infection, while computational approaches and the study of their structure-activity relationship (SAR) are the most eloquent and reliable platform for performing their hypothetical profile renovation. So, the main perspective of this investigation is to evaluate dual function of Fisetin and its derivatives against both virus and cancerous target. First and foremost, the prediction of activity spectra for materials (PASS) valuation has provided preliminary data on the antiviral, antibacterial, antiparasitic, and anti-cancer possibilities of the mentioned compounds. According to the evidence, PASS predicted scores were shown to perform better in antineoplastic and antiviral than antibacterial, and antiparasitic efficiency; as evidenced by their higher PASS scores in antineoplastic and antiviral drug tests. Breast cancer, Monkeypox, and Marburg virus have been selected as targeted pathogens, and different in silico studies were conducted to determine the dual function of mention derivatives. The "Lipinski five rules," on the other hand, has been subjected to extensive testing for drug-like characteristics. Molecular docking against Breast cancer, Monkeypox, and Marburg virus have been accomplished after confirmation of their bioactivity. The molecular docking evaluation against targeted disease displayed re-markable binding affinity and non-bonding engagement, with most of the results indicating that derivatives are more effective than the FDA approved standard antiviral, and antineoplastic drugs. Finally, the ADMET characteristics have been computed, and they indicate that the substance is suitable to use and did not have any chance to produce adverse effects on aquatic or non-aquatic environment, as well as having a highly soluble capacity in water medium, high G.I absorption rate, with outstanding bioavailability index. Therefore, these mentioned Fisetin derivatives could be suggested as potential medication against Breast cancer and newly reported Monkeypox, and Marburg virus, and may further proceed for laboratory experiment, synthesis, and clinical trials to evaluate their practical value.


Assuntos
Marburgvirus , Neoplasias , Humanos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Antivirais/farmacologia , Antibacterianos , Antiparasitários
3.
Plants (Basel) ; 12(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37111810

RESUMO

Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are the primary bacteria that cause clinical infections, such as urinary and intestinal infections, pneumonia, endocarditis, and sepsis. Bacterial resistance is an innate natural occurrence in microorganisms, resulting from mutations or the lateral exchange of genetic material. This serves as evidence for the association between drug consumption and pathogen resistance. Evidence has demonstrated that the association between conventional antibiotics and natural products is a promising pharmacological strategy to overcome resistance mechanisms. Considering the large body of research demonstrating the significant antimicrobial activities of Schinus terebinthifolius Raddi, the present study aimed to evaluate the chemical composition and antibiotic-enhancing effects of Schinus terebinthifolius Raddi essential oil (STEO) against the standard and multidrug-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The STEO was extracted by hydrodistillation using a Clevenger-type vacuum rotary evaporator. The Minimum Inhibitory Concentration (MIC) of the STEO was assessed by the microdilution method to evaluate the antibacterial activity. The antibiotic-enhancing activity of the essential oil was assessed by determining the MIC of antibiotics in the presence of a sub-inhibitory concentration (MIC/8) of the natural product. The GC-MS analysis revealed alpha-pinene (24.3%), gamma-muurolene (16.6%), and myrcene (13.7%) as major constituents of the STEO. The STEO potentiated the enhanced antibacterial activity of norfloxacin and gentamicin against all the strains and increased the action of penicillin against the Gram-negative strains. Therefore, it is concluded that although the STEO does not exhibit clinically effective antibacterial activity, its association with conventional antibiotics results in enhanced antibiotic activity.

4.
Front Vet Sci ; 9: 918961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118334

RESUMO

Poultry production contributes markedly to bridging the global food gap. Many nations have limited the use of antibiotics as growth promoters due to increasing bacterial antibiotic tolerance/resistance, as well as the presence of antibiotic residues in edible tissues of the birds. Consequently, the world is turning to use natural alternatives to improve birds' productivity and immunity. Withania somnifera, commonly known as ashwagandha or winter cherry, is abundant in many countries of the world and is considered a potent medicinal herb because of its distinct chemical, medicinal, biological, and physiological properties. This plant exhibits antioxidant, cardioprotective, immunomodulatory, anti-aging, neuroprotective, antidiabetic, antimicrobial, antistress, antitumor, hepatoprotective, and growth-promoting activities. In poultry, dietary inclusion of W. somnifera revealed promising results in improving feed intake, body weight gain, feed efficiency, and feed conversion ratio, as well as reducing mortality, increasing livability, increasing disease resistance, reducing stress impacts, and maintaining health of the birds. This review sheds light on the distribution, chemical structure, and biological effects of W. somnifera and its impacts on poultry productivity, livability, carcass characteristics, meat quality, blood parameters, immune response, and economic efficiency.

5.
Front Cell Infect Microbiol ; 12: 937481, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923801

RESUMO

The second wave of coronavirus disease 2019 (COVID-19) caused severe infections with high mortality. An increase in the cases of COVID-19-associated mucormycosis (CAM) was reported predominantly in India. Commonly present in immunocompromised individuals, mucormycosis is often a life-threatening condition. Confounding factors and molecular mechanisms associated with CAM are still not well understood, and there is a need for careful research in this direction. In this review, a brief account of the diagnosis, management, and advancement in drug discovery for mucormycosis has been provided. Here, we summarize major factors that dictate the occurrence of mucormycosis in COVID-19 patients through the analysis of published literature and case reports. Major predisposing factors to mucormycosis appear to be uncontrolled diabetes, steroid therapy, and certain cancers. At the molecular level, increased levels of iron in COVID-19 might contribute to mucormycosis. We have also discussed the potential role and regulation of iron metabolism in COVID-19 patients in establishing fungal growth. Other factors including diabetes prevalence and fungal spore burden in India as contributing factors have also been discussed.


Assuntos
COVID-19 , Diabetes Mellitus , Mucormicose , COVID-19/complicações , Humanos , Hospedeiro Imunocomprometido , Índia/epidemiologia , Mucormicose/diagnóstico , Mucormicose/tratamento farmacológico , Mucormicose/epidemiologia
6.
Molecules ; 28(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36615391

RESUMO

This review summarized the current breakthroughs in the chemistry of acridines as anti-cancer agents, including new structural and biologically active acridine attributes. Acridine derivatives are a class of compounds that are being extensively researched as potential anti-cancer drugs. Acridines are well-known for their high cytotoxic activity; however, their clinical application is restricted or even excluded as a result of side effects. The photocytotoxicity of propyl acridine acts against leukaemia cell lines, with C1748 being a promising anti-tumour drug against UDP-UGT's. CK0403 is reported in breast cancer treatment and is more potent than CK0402 against estrogen receptor-negative HER2. Acridine platinum (Pt) complexes have shown specificity on the evaluated DNA sequences; 9-anilinoacridine core, which intercalates DNA, and a methyl triazene DNA-methylating moiety were also studied. Acridine thiourea gold and acridinone derivatives act against cell lines such as MDA-MB-231, SK-BR-3, and MCF-7. Benzimidazole acridine compounds demonstrated cytotoxic activity against Dual Topo and PARP-1. Quinacrine, thiazacridine, and azacridine are reported as anti-cancer agents, which have been reported in the previous decade and were addressed in this review article.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Antineoplásicos/química , Linhagem Celular , Substâncias Intercalantes/farmacologia , DNA/metabolismo , Neoplasias da Mama/tratamento farmacológico , Acridinas/farmacologia , Acridinas/química , Linhagem Celular Tumoral
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