Biology subjects

Govindaswamy, B.

Publications and source records attributed to Govindaswamy, B..

3 recordsLinked to original sources

bioRxiv2026

Sequential- vs. density gradient- centrifugation for the isolation of mitochondria-containing extracellular vesicles

A subset of extracellular vehicles (EVs) with particle diameters >200 nm, large vesicles (lEVs) contain mitochondria that increase recipient cell bioenergetics. To date, sequential centrifugation (SC) is the most reported protocol to separate lEVs from the smaller EVs (<200 nm)/exosomes. We have previously demonstrated that lEVs derived from brain endothelial cells (BECs) using the standard SC method transferred their innate mitochondria to recipient BECs, increased recipient BEC bioenergetics, reduced brain infarct volume, and improved behavioral outcomes in a mouse model of transient ischemic stroke. Despite their promising therapeutic activity, SC-isolated lEVs are likely a mixture of mitochondria-containing lEVs and non-mitochondria-containing lEVs. We hypothesized that subsequent purification of SC-isolated lEVs using density-gradient centrifugation (DGC) may yield a purer sample of mitochondria-containing lEVs. We established a DGC protocol to purify lEVs. In this pilot study, lEVs isolated using SC and DGC protocols were compared to determine their physicochemical characteristics and their effects on recipient BEC bioenergetics. SC-lEVs and DGC-lEVs both significantly restored ATP levels in OGD-injured BECs with no difference between groups. However, a Seahorse mitochondrial function assay revealed distinct functional effects: SC-lEVs did not significantly alter respiration, whereas DGC-lEVs induced a dose-dependent increase in oxygen consumption rate, indicating enhanced oxidative phosphorylation. These findings demonstrate that DGC purification yields a more mitochondria-enriched and functionally potent lEV preparation with an enhanced capacity to restore oxidative phosphorylation in ischemic BECs. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/732469v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@102b68borg.highwire.dtl.DTLVardef@11e7df1org.highwire.dtl.DTLVardef@de7161org.highwire.dtl.DTLVardef@1e5d64c_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2024

Anti Alzheimer's effects of Neem oil nanoemulsion against Amyloid β1-40 induced in human neuroblastoma SH-SY5Y cell line

Alzheimers disease is characterized by cognitive decline associated with neurodegeneration and accumulation of amyloid beta. Here, experimenting with in vitro models of AD using SHSY5Y cell line after exposing them with A{beta}1-40. The natural derivatives like neem oil, plays a potential role in neuroprotection and reduction of tau aggregates in animal models, eventually becoming a alternative treatment beneficiaries in neurodegenerative disease. Formulating the neem oil into a nanoemulsion with Tween 80(R) and Brij 30 for stabilization, can be a beneficial drug development for AD. The optimization of this neem oil nanoemulsion was performed with Response Surface Methodology - Box Behnken Design, showed the S mix 10, Sonication power 55%, and Sonication time 15%; as the optimized value to synthesize a stable neem oil nanoemulsion. Secondly, they subjected to thermodynamic stability analysis for estimating the shelf life duration with different temperature conditions. Amyloid beta induced SHSY5Y tend to show severe cell oxidative stress, to estimate that, the neem oil and neem oil nanoemulsion were subjected to DPPH assay. Further, the neem oil and neem oil nanoemulsion analyzed with the A{beta}1-40 induced SHSY5Y, resulted in good cytotoxicity, where the nanoemulsion exhibited more reduction in cell viability than neem oil. This trend shows that synthesizing the natural oils into nanocarriers can potentially increase the drug release rate, enhanced stability and good biomedical application

bioengineering↗

bioRxiv2024

In vitro anti cancer, anti inflammatory and anti oxidant activity of Celery oil (Apium graveolens)-Myristic acid based microemulsion system: Characterization and Biomedical application

Plant based compounds are frequently modified, developed into drug components to treat different types of cancer. Celery is one of the most used ingredients in daily life, exhibits potential medicinal properties and myristic acid exhibits anti microbial and inflammatory properties making it ideal candidate for combinational therapy. This study demonstrates the formulation of celery oil-myristic acid based microemulsion system with sequence of weight/volume of components to optimize stable microemulsion. the sequence of formulations were performed, optimized through pseudo ternary phase diagram and stability analysis, of which CMA ME 4 formulation were observed to transparent and stable. This CMA ME 4 was analyzed using DLS for particle size which is found to be 14.0{+/-}27.1 and PDI 0.34{+/-}0.46 through 5th day to 30th day. In vitro drug release study has been performed with stimulated physiological condition (pH 5.6) and stimulated tumor tissue (pH 7.4), the microemulsion was withdrawn in time intervals and the kinetic model is constructed to detect the behaviour of the drug release profile. Further, anti inflammatory, anti diabetic and anti obesity assays were performed to analyse the potentiality of CMA ME 4 microemulsion formulation, where the results exhibited from 80 to 90% radical scavenging and inhibition compared with the synthetic drugs. A good cytotoxic activity of CMA ME 4 microemulsion was determined by positive results of the MTT assay performed with HeLa with 80 to 90% cell death, MCF7 with 80 to 90% cell death and HUVECs was used to determine the toxicity level when the microemulsion interacts with the normal cell which is found to be 80 to 90% cell viability over time. These findings more suitably suggest that combination of natural oil with synthetic components can be effective in treatment against diseases.

pharmacology and toxicology↗