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Discovery of exosomes as modulator of cellular communication has added a new dimension to our understanding of biological processes. Exosomes influence the biological systems by mediating trans-communication across tissues and cells, which has important implication for health and disease. In absence of well-characterized modulators of exosome biogenesis, an alternative option is to target pathways generating important exosomal components. Cholesterol represents one such essential component required for exosomal biogenesis. We initiated this study to test the hypothesis that owing to its cholesterol lowering effect, simvastatin, a HMG CoA inhibitor, might be able to alter exosome formation and secretion. Simvastatin was tested for its effect on exosome secretion under various in-vitro and in-vivo settings and was found to reduce the secretion of exosome from various cell-types. It was also found to alter the levels of various proteins important for exosome production. Murine model of Acute Airway Inflammation was used for further validation of our findings. We believe that the knowledge acquired in this study holds potential for extension to other exosome dominated pathologies and model systems.

Amphipathic peptides constitute a class of molecules with the potential to develop as efficient and safer alternatives to viral and other nonviral vectors for intracellular delivery of therapeutics. These peptides can be useful for nucleic acid delivery and hence promise to have pharmaceutical application, particularly in gene therapy. In order to design novel amphipathic peptides and improve their efficiency of therapeutic cargo delivery, one needs to understand the role of the physicochemical properties of the peptide. There are very few reports in the literature where the physicochemical properties of the peptide have been correlated with efficiency of plasmid DNA delivery. In the present work we hunted out a naturally occurring amphipathic peptide termed Mgpe-1 (derived from HUMAN Protein phosphatase 1E) as a possible novel DNA delivery agent. We systematically altered the physicochemical parameters of this peptide to further enhance its DNA delivery efficiency. We changed its amphipathicity (from secondary to primary), the total charge (from +6 to +9), hydrophobicity, and the amino acid composition (lysine and serines to arginine; substitution of tryptophan) and studied which of these alterations affect DNA delivery efficiency. Our results showed that although Mgpe-1 exhibited very strong cellular uptake, its plasmid DNA delivery efficiency was poor. The presence of nine arginines improved the DNA delivery efficiency, and the effect was observed in both the primary and the secondary amphipathic variants. We further observed that the presence of tryptophan was important but not essential and the effect of its removal was stronger in the case of the secondary amphipathic peptide. However, increase in total hydrophobicity of the peptide led to a fall in transfection efficiency in the primary amphipathic peptide whereas the secondary amphipathic peptide having the same chemical composition was almost unaffected by this change. The primary amphipathic peptides with high positive charge and low hydrophobicity formed colloidally stable polyplexes with DNA and avoided a major impediment in DNA delivery, namely, the aggregation of polyplexes and cytotoxicity. The secondary amphipathic variants by virtue of the positional arrangement of the amino acids led to formation of polyplexes with partly hydrophilic surfaces which prevented aggregation and controlled particle size irrespective of the hydrophobicity. Two variants in the series Mgpe-3 and Mgpe-4 having nine positive charges with less hydrophobicity showed high transfection efficiency in multiple cell lines along with serum stability and much less cytotoxicity and promise to be novel and efficient DNA delivery vectors.

The widespread availability and use of modern synthetic therapeutic agents have led to a massive decline in ethnomedical therapies. However, these synthetic agents often possess toxicity leading to various adverse effects. For instance, anti-tubercular treatment (ATT) is toxic, lengthy, and severely impairs host immunity, resulting in posttreatment vulnerability to reinfection and reactivation of tuberculosis (TB). Incomplete ATT enhances the risk for the generation of multidrug-or extensively drug-resistant (MDR or XDR, respectively) variants of Mycobacterium tuberculosis (M. tb), the TB-causing microbe. Therefore, a new therapeutic approach that minimizes these risks is urgently needed to combat this deadly disease and prevent future TB epidemics. Previously, we have shown that the phytochemical bergenin induces T helper 1 (Th1)-and Th17 cellbased protective immune responses and potently inhibits mycobacterial growth in a murine model of M. tb infection, suggesting bergenin as a potential adjunct agent to TB therapy. Here, we combined ATT therapy with bergenin and found that this combination reduces immune impairment and the length of treatment in mice. We observed that co-treatment with the anti-TB drug isoniazid and bergenin produces additive effects and significantly reduces bacterial loads compared with isoniazid treatment alone. The bergenin co-treatment also reduced isoniazid-induced immune impairment; promoted long-lasting, antigen-specific central memory T cell responses; and acted as a self-propelled vaccine. Of note, bergenin treatment significantly reduced the bacterial burden of a multidrug-resistant TB strain. These observations suggest that bergenin is a potent immunomodulatory agent that could be further explored as a potential adjunct to TB therapy. cro ARTICLE

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Milk is globally consumed as a rich source of protein and calcium. A major protein component of milk is casein, with β-casein having 2 major variants A1 and A2. Of these, A1 casein variant has been implicated as a potential etiological factor in several pathologies, but direct effect on lungs has not been studied. The objective of the present study was to evaluate the A1and A2 β casein variants of cow milk as factors causing allergic airway disease in murine model. Mice fed with A1A1 milk exhibited increased airway hyperresponsiveness with increasing concentration of bronchoconstrictor (methacholine), which was not observed in mice fed with A2A2 milk. Significantly elevated levels of IL-4 and IL-5 were found in bronchoalveolar lavage and serum of A1A1 variant fed mice. Increased IgE and IgG levels along with increased infiltration of lymphocytes and eosinophils, leading to peribronchial inflammation was also observed in A1A1 variant fed mice, although, no goblet cell hyperplasia or airway remodeling was observed. In contrast, A2A2 milk fed mice presented phenotype matching the control group, while A1A2 milk fed group presented an intermediate phenotype. In summary, our results show that A1 form of cow milk has a proinflammatory effect on the lung resulting in phenotype closely matching with the typical allergic asthma phenotype.