Central Drug Research Institute

About: Central Drug Research Institute is a facility organization based out in Lucknow, Uttar Pradesh, India. It is known for research contribution in the topics: Leishmania donovani & Brugia malayi. The organization has 4357 authors who have published 7257 publications receiving 143871 citations. The organization is also known as: Central Drug Research Institute, Lucknow & CDRI.

Core engagement with β-arrestin is dispensable for agonist-induced vasopressin receptor endocytosis and ERK activation

Abstract: G protein-coupled receptors (GPCRs) exhibit highly conserved activation and signaling mechanisms by which agonist stimulation leads to coupling of heterotrimeric G proteins and generation of second messenger response. This is followed by receptor phosphorylation, primarily in the carboxyl terminus but also in the cytoplasmic loops, and subsequent binding of arrestins. GPCRs typically recruit arrestins through two different sets of interactions, one involving phosphorylated receptor tail and the other mediated by the receptor core. The engagement of both set of interactions (tail and core) is generally believed to be necessary for arrestin-dependent functional outcomes such as receptor desensitization, endocytosis, and G protein-independent signaling. Here we demonstrate that a vasopressin receptor (V2R) mutant with truncated third intracellular loop (V2RΔICL3) can interact with β-arrestin 1 (βarr1) only through the phosphorylated tail without engaging the core interaction. Of interest, such a partially engaged V2RΔICL3-βarr1 complex can efficiently interact with clathrin terminal domain and ERK2 MAPK in vitro. Furthermore, this core interaction-deficient V2R mutant exhibits efficient endocytosis and ERK activation upon agonist stimulation. Our data suggest that core interaction with βarr is dispensable for V2R endocytosis and ERK activation and therefore provide novel insights into refining the current understanding of functional requirements in biphasic GPCR-βarr interaction.

Biocompatible fluorescent carbon quantum dots prepared from beetroot extract for in vivo live imaging in C. elegans and BALB/c mice

Abstract: Luminescent carbon quantum dots (CQDs) prepared from aqueous beetroot extract were developed as unique fluorescent nanomaterials for in vivo live animal imaging applications. Blue (B) and green (G) emitting environmentally benign CQDs (particle size of 5 nm and 8 nm, respectively) exhibited bright fluorescence in aqueous medium and were found to be biocompatible, photostable and non-toxic in animal models. The in vivo imaging and toxicity evaluation of both CQDs were performed for the first time in the Caenorhabditis elegans (C. elegans) model, which revealed consistent fluorescence in the gut tissues of the worms without exerting any sign of toxic effects on the nematodes. The in vivo bio-distribution of G-CQDs given by tail vein injection in live BALB/c mice showed optical signals in the lower abdominal regions, mainly in the intestine, and cleared from the body through faeces. The tremendous potential shown by these eco-friendly CQDs in the C. elegans and mice models advocates new hopes for greener CQD nanomaterials as diagnostic tools in the biomedical field.

Antileishmanial activity of nano-amphotericin B deoxycholate

Abstract: Objectives: The aim of the present study was to compare the efficacy of a nano form of amphotericin B deoxycholate with that of conventional amphotericin B deoxycholate for the treatment of visceral leishmaniasis. Methods: We have formulated nanoparticles (10‐20 nM) from amphotericin B deoxycholate (1‐2 mM) by applying high-pressure (150 argon) milling homogenization and have tested their efficacy in a J774A cell line and in hamsters. Parasite survival and tissue burden in spleen were evaluated for nanoamphotericin B and conventional amphotericin B. Both nano-amphotericin B and conventional amphotericin B were injected intraperitoneally at 5 mg/kg per day for 5 days. Results: The inhibition of amastigotes in the splenic tissue with nano-amphotericin B was significantly more than with conventional amphotericin B (92.18% versus 74.57%, P 5 0.005). Similarly, the suppression of parasite replication in the spleen was also found to be significant (99.18% versus 97.17%, P 5 0.05). In a cytotoxicity test, nano-amphotericin B against the J774A cell line had a CC50 of 12.67 mg/L in comparison with 10.61 mg/L for amphotericin B, far higher than the doses used for ED50. Conclusions: Nanoparticles of amphotericin B had significantly greater efficacy than conventional amphotericin B. This formulation may have a favourable safety profile, and if production costs are low, it may prove to be a feasible alternative to conventional amphotericin B.