Biology subjects

Dravid, A. A.

Publications and source records attributed to Dravid, A. A..

5 recordsLinked to original sources

bioRxiv2026

Dissolution-Controlled Nanocrystalline Rifapentine Formulation for Tuberculosis Treatment

Current tuberculosis (TB) treatment suffers from drawbacks such as long regimens, high pill burden and side effects leading to non-adherence and poor treatment outcomes. Dissolution-controlled drug depot formulation with high drug loading is a clinically successful drug delivery strategy. Such depots reduce the dosing frequency for treatments requiring daily administration, thereby improving treatment adherence and compliance. However, dissolution-controlled depots for first-line TB drugs have not been demonstrated due to their high solubility and high dose requirements. In this study, we overcame this challenge by developing injectable, extended-release, dissolution-controlled depots of nanocrystalline rifapentine (NCRPT), microcrystalline rifapentine (MCRPT) and amorphous rifapentine microparticles (ARPT) with more than 75% loading. Crystalline formulations resulted in much slower depot dissolution compared to amorphous formulations. A single intramuscular (IM) injection of NCRPT in mice resulted in therapeutic serum concentrations for over a week. We then demonstrated the efficacy of NCRPT in both pre-exposure prophylaxis and therapeutic models of mice TB. NCRPT administered at 60 mg/kg once every two weeks demonstrated excellent efficacy in a mouse model of TB infection. In each case, a [~] 4-log-fold reduction in lung bacterial load compared to untreated mice was observed. These results open new avenues for developing LAI formulations of TB drugs and could improve patient compliance and TB management.

bioengineering↗

bioRxiv2023

Sustained release Resolvin D1 liposomes are effective in the treatment of osteoarthritis in obese mice

Osteoarthritis (OA) is the most common joint disorder and currently affects > 500 million patients worldwide, with ~60% of them also suffering from obesity. There is no drug approved for human use that changes the course of OA progression. OA is one of the most common comorbidities of obesity, and obesity-related OA (ObOA) is a serious health concern because it shows heightened severity of tissue damage and also predominantly affects the working population. Unresolved inflammation is a major driver of ObOA, thus, resolving disease-associated inflammation is a viable strategy to treat ObOA. Resolvins are highly potent molecules that play a role in the resolution of inflammation and promote tissue healing. However, small molecules (like Resolvin D1; RvD1) have to be administered frequently or prior to injury because they lose their in vivo activity rapidly either by lymphatic clearance, or oxidation-mediated deactivation. In this study, we have encapsulated RvD1 in liposomes and established its efficacy in the mouse model of ObOA at much lower dosages than freely administered RvD1. Liposomal RvD1 (lipo-RvD1) acted as a source of the RvD1 molecules for ~11 days in vitro in synovial fluid derived from patients. When administered prophylactically or therapeutically, lipo-RvD1 suppressed cartilage damage in male C57BL/6 mice compared to untreated and free RvD1 treatments. This efficacy was achieved by increasing the proportion of the proresolution M2 macrophages over proinflammatory M1 macrophages in the synovial membrane. These results show the potential of lipo-RvD1 as an anti-OA agent. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=141 SRC="FIGDIR/small/525015v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@141d889org.highwire.dtl.DTLVardef@1ef1753org.highwire.dtl.DTLVardef@1e463c1org.highwire.dtl.DTLVardef@15138c6_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstract:C_FLOATNO Mechanism of working of lipo-RvD1 in ObOA joint. C_FIG

bioengineering↗

bioRxiv2022

Immunomodulatory effect of mycobacterial outer membrane vesicles coated nanoparticles

Tuberculosis (TB) is one of the most widely prevalent infectious diseases that cause significant mortality. Bacillus Calmette-Guerin (BCG), the current TB vaccine used in clinics, shows variable efficacy and has safety concerns for immunocompromised patients. There is a need to develop new and more effective TB vaccines. Outer membrane vesicles (OMVs) are vesicles released by Mycobacteria that contain several lipids and membrane proteins and act as a good source of antigens to prime immune response. However, the use of OMVs as vaccines has been hampered by their heterogeneous size and low stability. Here we report that mycobacterial OMVs can be stabilized by coating over uniform-sized 50 nm gold nanoparticles. The OMV-coated gold nanoparticles (OMV-AuNP) show enhanced uptake and activation of macrophages and dendritic cells. Proteinase K and TLR inhibitor studies demonstrated that the enhanced activation was attributed to proteins present on OMVs and was mediated primarily by TLR2 and TLR4. Mass spectrometry analysis revealed several potential membrane proteins that were common in both free OMVs and OMV-AuNP. Such strategies may open up new avenues and the utilization of novel antigens for developing TB vaccines.

bioengineering↗

bioRxiv2021

Cationic inhalable particles for enhanced drug delivery to M. tuberculosis infected macrophages

Inhalable microparticle-based drug delivery platforms are being investigated extensively for Tuberculosis (TB) treatment as they offer efficient deposition in lungs and improved pharmacokinetics of the encapsulated cargo. However, the effect of physical parameters of microcarriers on interaction with Mycobacterium tuberculosis (Mtb) infected mammalian cells is underexplored. In this study, we report that Mtb-infected macrophages are highly phagocytic and microparticle surface charge plays a major role in particle internalization by infected cells. Microparticles of different sizes (0.5 - 2 m) were internalized in large numbers by Mtb-infected THP-1 macrophages and murine primary Bone Marrow Derived Macrophages in vitro. Drastic improvement in particle uptake was observed with cationic particles in vitro and in mice lungs. Rapid uptake of rifampicin-loaded cationic microparticles allowed high intracellular accumulation of the drug and lead to enhanced anti-bacterial function when compared to non-modified rifampicin-loaded microparticles. Cytocompatibility assay and histological analysis in vivo confirmed that the formulations were safe and did not elicit any adverse reaction. Additionally, pulmonary delivery of cationic particles in mice resulted in two-fold higher uptake in resident alveolar macrophages compared to non-modified particles. This study provides a framework for future design of drug carriers to improve delivery of anti-TB drugs inside Mtb-infected cells.

bioengineering↗

bioRxiv2021

Rapamycin microparticles induce autophagy, prevent senescence and are effective in treatment of Osteoarthritis

Trauma to the knee joint is associated with significant cartilage degeneration and erosion of subchondral bone, which eventually leads to osteoarthritis (OA), resulting in substantial morbidity and healthcare burden. With no disease-modifying drugs in clinics, the current standard of care focuses on symptomatic relief and viscosupplementation. Modulation of autophagy and targeting senescence pathways are emerging as potential treatment strategies. Rapamycin has shown promise in OA disease amelioration by autophagy upregulation, yet its clinical use is hindered by difficulties in achieving therapeutic concentrations, necessitating multiple weekly injections. Here, we have synthesized rapamycin - loaded poly (lactic-co-glycolic acid) microparticles (RMPs) that induced autophagy, prevented senescence and sustained sulphated glycosaminoglycans(sGAG) production in primary human articular chondrocytes from OA patients. RMPs were potent, nontoxic, and exhibited high retention time (up to 35 days) in mice joints. Intra-articular delivery of RMPs effectively mitigated cartilage damage and inflammation in surgery-induced OA when administered as a prophylactic or therapeutic regimen. Together, our studies demonstrate the feasibility of using RMPs as a potential clinically translatable therapy to prevent and treat post-traumatic osteoarthritis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=97 SRC="FIGDIR/small/453073v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@29863org.highwire.dtl.DTLVardef@628da3org.highwire.dtl.DTLVardef@40ec6eorg.highwire.dtl.DTLVardef@626355_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗