Nanotechnology and tuberculosis: An old disease with new treatment strategies.

Tuberculosis is an intracellular infectious disease caused by Mycobacterium tuberculosis, which mainly affects the lungs. Especially in patients infected by the Human Immunodeficiency Virus (HIV) or other immunosuppressed patients, tuberculosis is considered one of the infectious diseases with higher morbidity and mortality rates. Despite considerable improvements in diagnosis and treatment during the last decades, the drugs currently used in tuberculosis treatment still have limitations, such as low plasma levels after oral administration, low solubility in water, fast metabolization by the liver with a short 1/2 life and low patient adherence to treatment. Another limiting point is drug-resistant strains. Thus, to overcome such limitations, nanotechnology emerges as a promising alternative due to the drug release systems and its recent advances that show potential improvements, such as improved bioavailability and reduction of the therapeutic dose. In this context, this manuscript aimed to highlight the nanotechnology-based drug delivery systems studies pointing to those most effective for tuberculosis treatment. Studies based on polymeric nanoparticles are promising in diagnosing, treating, and even preventing tuberculosis because they have the high stability and transport capacity of these drugs. Solid lipid nanoparticles are another type of promising nanocarriers for treating tuberculosis, mainly for delivering drugs to the remote lymphatic system. Other promising nanosystems are the liposomes, since they have also shown efficacy in significantly reducing bacterial load compared to conventional drug administration. Given the results presented, the administration of drugs through nanotechnology-based drug delivery systems has benefits in treating tuberculosis since in vitro and in vivo studies have revealed that nanotechnology through nano- and micro-scale systems is an effective and promising approach for the treatment of tuberculosis. Furthermore, the increase in the number of patents for nanosystems aimed at treating TB has demonstrated researchers' commitment in the quest to improve the therapeutic arsenal against tuberculosis.