RESUMO
Tuberculosis (TB), caused by Mycobacterium tuberculosis, continues to pose a significant threat to global health. The resilience of TB is amplified by a myriad of physical, biological, and biopharmaceutical barriers that challenge conventional therapeutic approaches. This review navigates the intricate landscape of TB treatment, from the stealth of latent infections and the strength of granuloma formations to the daunting specters of drug resistance and altered gene expression. Amidst these challenges, traditional therapies often fail, contending with inconsistent bioavailability, prolonged treatment regimens, and socioeconomic burdens. Nanoscale Drug Delivery Systems (NDDSs) emerge as a promising beacon, ready to overcome these barriers, offering better drug targeting and improved patient adherence. Through a critical approach, we evaluate a spectrum of nanosystems and their efficacy against MTB both in vitro and in vivo. This review advocates for the intensification of research in NDDSs, heralding their potential to reshape the contours of global TB treatment strategies.
RESUMO
The growth of the white-rot basidiomycete Pleurotus sajor-caju in malt-agar plates was inhibited by three naturally occurring, plant-derived naphthoquinones: juglone, lawsone, and plumbagin. The latter two compounds exerted the most potent antifungal activity, and lawsone killed the mycelium at concentrations higher than 200 ppm. Plates containing juglone and lawsone presented large decolorized areas extending from area of fungal growth, suggesting an extracellular enzymatic degradation of these quinones. Screening of culture plates for extracellular enzymatic activities revealed the presence of both laccase and veratryl alcohol oxidase in most plates, the diffusion of both enzymes matching the decolorized area. In agitated cultures, the presence of juglone was found to stimulate the production of veratryl alcohol oxidase in a significant manner. This is the first time degradation of plant derived naphthoquinones by a white-rot fungus is reported.
Assuntos
Naftoquinonas/metabolismo , Naftoquinonas/farmacologia , Plantas/química , Pleurotus/efeitos dos fármacos , Pleurotus/crescimento & desenvolvimento , Biodegradação Ambiental , Meios de Cultura , Testes de Sensibilidade MicrobianaRESUMO
Retinoic acid, the active metabolite of vitamin A, plays a role in the growth and differentiation of a variety of normal and malignant cells. In response to 5 microM retinoic acid the human hepatoma-derived cell line HepG2 underwent significant growth inhibition (not associated with cell death), which reached a level of 80% in comparison with controls, after 12 days of continuous treatment. Retinoic acid also induced morphological changes in these cells, in particular the development of canalicular-like structures, indicating progression to a more differentiated phenotype. In addition, a reduced expression of alpha-fetoprotein was found. We suggest that our results may be important for the design of novel therapeutic approaches using RA for the treatment of liver tumors.