Alzheimer's Disease and Parkinson's Disease: A Review of Current Treatment Adopting a Nanotechnology Approach.

Neurodegenerative disorders (NDDs) are characterized by the progressive loss of structure or neuron function, often associated with neuronal death. Treatments for neurodegenerative diseases only address symptoms without having any disease-modifying effect but serious side effects. Currently, there is no effective treatment for NDDs. This is due to the poor flow of drugs to the blood-barrier brain (BBB) which does not allow macromolecules like proteins and peptides to pass through it. Targeted drug delivery to the central nervous system (CNS) for the diagnosis and treatment of NDDs, such as Alzheimer's disease (AD), is restricted due to the limitations posed by the BBB as well as opsonization by plasma proteins in the systemic circulation and peripheral side-effects. Nanotechnology thereby presents a broad approach for transporting molecules through the BBB, thus allowing the entry of substances acting directly on the site affected by the disease. The aim of this review is to outline current strategies in nanotechnology for treating Alzheimer's and Parkinson's diseases.

Effect of antimicrobial peptides on ATPase activity and proton pumping in plasma membrane vesicles obtained from mycobacteria.

The potential usefulness of antimicrobial peptides (AMPs) as antimycobacterial compounds has not been extensively explored. Although a myriad of studies on AMPs from different sources have been done, some of its mechanisms of action are still unknown. Maganins are of particular interest since they do not lyse non-dividing mammalian cells. In this work, AMPs with well-recognized activity against bacteria were synthesized, characterized, purified and their antimycobacterial activity and influence on ATPase activity in mycobacterial plasma membrane vesicles were assessed. Using bioinformatics tools, a magainin-I analog peptide (MIAP) with improved antimicrobial activity was designed. The influence of MIAP on proton (H(+)) pumping mediated by F(1)F(0)-ATPase in plasma membrane vesicles obtained from Mycobacterium tuberculosis was evaluated. We observed that the antimycobacterial activity of AMPs was low and variable. However, the activity of the designed peptide MIAP against M. tuberculosis was 2-fold higher in comparison to magainin-I. The basal ATPase activity of mycobacterial plasma membrane vesicles decreased approximately 24-30% in the presence of AMPs. On the other hand, the MIAP peptide completely abolished the F(1)F(0)-ATPase activity involved in H(+) pumping across M. tuberculosis plasma membranes vesicles at levels similar to the specific inhibitor N,N' dicyclohexylcarbodiimide. These finding suggest that AMPs can inhibit the H(+) pumping F(1)F(0)-ATPase of mycobacterial plasma membrane that potentially interferes the internal pH and viability of mycobacteria.