Development and preclinical evaluation of microneedle-assisted resveratrol loaded nanostructured lipid carriers for localized delivery to breast cancer therapy.

Resveratrol (RVT) is one of the potent anticancer phytochemicals which has shown promising potential for breast cancer therapy. However, its short half-life and low bioavailability is a major hurdle in its effective use. In this study, we have developed nanostructured lipid carriers (NLCs) of RVT to enable localized delivery of the drug to the breast tissues using microneedle arrays to improve effectiveness. The NLCs were optimized using the Design of Experiments approach and characterized for their particle size, polydispersity index, zeta potential and entrapment efficiency. The RVT-NLCs delivered using microneedle array 1200 showed a higher permeation of RVT across the skin with lower skin retention compared to pure RVT. Further, RVT-NLCs showed higher anticancer activity on MDA-MB-231 breast cancer cell lines and enhanced internalization compared to pure RVT. Moreover, the RVT-NLCs were found to inhibit the migration of MDA-MB-231 breast cancer cell lines. Preclinical studies in rats showed that RVT-NLCs delivered via microneedles demonstrated a remarkable increase in the Cmax, Tmax and AUC0-inf, and a higher localization in breast tissue compared to pure RVT administered orally. These results suggests that the RVT-NLCs administered by microneedle array system is an effective strategy for the local delivery of RVT for breast cancer therapy.

A defined medium for Leishmania culture allows definition of essential amino acids.

Axenic culture of Leishmania is generally performed in rich, serum-supplemented media which sustain robust growth over multiple passages. The use of such undefined media, however, obscures proteomic analyses and confounds the study of metabolism. We have established a simple, defined culture medium that supports the sustained growth of promastigotes over multiple passages and which yields parasites that have similar infectivity to macrophages to parasites grown in a conventional semi-defined medium. We have exploited this medium to investigate the amino acid requirements of promastigotes in culture and have found that phenylalanine, tryptophan, arginine, leucine, lysine and valine are essential for viability in culture. Most of the 20 proteogenic amino acids promote growth of Leishmania promastigotes, with the exception of alanine, asparagine, and glycine. This defined medium will be useful for further studies of promastigote substrate requirements, and will facilitate future proteomic and metabolomic analyses.

TrypanoCyc: a community-led biochemical pathways database for Trypanosoma brucei.

The metabolic network of a cell represents the catabolic and anabolic reactions that interconvert small molecules (metabolites) through the activity of enzymes, transporters and non-catalyzed chemical reactions. Our understanding of individual metabolic networks is increasing as we learn more about the enzymes that are active in particular cells under particular conditions and as technologies advance to allow detailed measurements of the cellular metabolome. Metabolic network databases are of increasing importance in allowing us to contextualise data sets emerging from transcriptomic, proteomic and metabolomic experiments. Here we present a dynamic database, TrypanoCyc (http://www.metexplore.fr/trypanocyc/), which describes the generic and condition-specific metabolic network of Trypanosoma brucei, a parasitic protozoan responsible for human and animal African trypanosomiasis. In addition to enabling navigation through the BioCyc-based TrypanoCyc interface, we have also implemented a network-based representation of the information through MetExplore, yielding a novel environment in which to visualise the metabolism of this important parasite.