Anila Mathew

Curcumin Loaded-PLGA Nanoparticles Conjugated with Tet-1 Peptide for Potential Use in Alzheimer's Disease

Alzheimers disease is a growing concern in the modern world. As the currently available medications are not very promising, there is an increased need for the fabrication of newer drugs. Curcumin is a plant derived compound which has potential activities beneficial for the treatment of Alzheimers disease. Anti-amyloid activity and anti-oxidant activity of curcumin is highly beneficial for the treatment of Alzheimers disease. The insolubility of curcumin in water restricts its use to a great extend, which can be overcome by the synthesis of curcumin nanoparticles. In our work, we have successfully synthesized water-soluble PLGA coated- curcumin nanoparticles and characterized it using different techniques. As drug targeting to diseases of cerebral origin are difficult due to the stringency of blood-brain barrier, we have coupled the nanoparticle with Tet-1 peptide, which has the affinity to neurons and possess retrograde transportation properties. Our results suggest that curcumin encapsulated-PLGA nanoparticles are able to destroy amyloid aggregates, exhibit anti-oxidative property and are non-cytotoxic. The encapsulation of the curcumin in PLGA does not destroy its inherent properties and so, the PLGA-curcumin nanoparticles can be used as a drug with multiple functions in treating Alzheimers disease proving it to be a potential therapeutic tool against this dreaded disease.

Hybrid fluorescent curcumin loaded zein electrospun nanofibrous scaffold for biomedical applications

Nanomedicine utilizes engineered nanodevices and nanostructures for monitoring, repair, construction and control of human biological systems at the molecular level. In this study, we investigated the feasibility and potential of zein nanofiber as a delivery vehicle for curcumin in biomedical applications. By optimizing the electrospinning parameters, ultrafine zein fluorescence nanofibers containing curcumin were developed with interconnected fibrous networks. We found that these nanofibers show an increase in fluorescence due to the incorporation of curcumin. The morphology and material properties of the resulting multifunctional nanofiber including the surface area were examined by a field emission-scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and confocal microscopy. The surface area and pore size were characterized by N(2) adsorption-desorption isotherm. SEM and fluorescence images showed that the uniform fibers with smooth surface had an average diameter of about 310 nm. An in vitro degradation study showed significant morphological changes. The in vitro evaluations suggested that the curcumin incorporated zein nanofibers showed sustained release of curcumin and maintained its free radical scavenging ability. It provides an attractive structure for the attachment and growth of fibroblast as cell culture surfaces. The results demonstrate that the curcumin loaded zein nanofiber could be a good candidate for soft tissue engineering scaffolds and has the potential for further applications in drug delivery system.

Aptamer-labeled PLGA nanoparticles for targeting cancer cells

Cancer is one of the leading causes of death in most parts of the world and is a very serious cause of concern particularly in developing countries. In this work, we prepared and evaluated the aptamer-labeled paclitaxel-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Apt-PTX-PLGA NPs) which can ameliorate drug bioavailability and enable accurate drug targeting to cancer cells with controlled drug release for cancer therapy. Paclitaxel-loaded PLGA nanoparticles (PTX-PLGA NPs) were formulated by a single-emulsion/solvent evaporation method and were further surface-functionalized with a chemical cross-linker bis(sulfosuccinimidyl) suberate (BS3) to enable binding of aptamer on to the surface of the nanoparticles. The prepared nanoparticles were characterized by atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Cytotoxicity studies were carried out using normal human mammary epithelial cells (HMEC cells) and human glial cancer cells (GI-1 cells) by methylthiazolyldiphenyl-tetrazolium bromide assay and Alamar blue assay, which confirmed that PTX-PLGA NPs with aptamer conjugation (Apt-PTX-PLGA NPs) were comparatively non-toxic to HMEC cells while toxic to GI-1 cancer cells. Cellular uptake of PTX-PLGA NPs with and without aptamer conjugation was studied using GI-1 cells and monitored by confocal microscopy and phase contrast microscopy. Our studies demonstrated significant internalization and retention of nanoparticles inside the cells, inducing apoptosis. The preferential accumulation of PTX-PLGA NPs within the cancer cells were also confirmed by flow cytometry-based uptake studies. The results indicated that Apt-PTX-PLGA NPs could be a promising targeted therapeutic delivery vehicle for cancer treatment.

CHAPTER 6:Nanotechnology in Anti-Aging: Nutraceutical Delivery and Related Applications

Nutraceuticals and functional food provide nutritional benefits along with preventive and therapeutic effects against various diseases, including aging-related conditions. Most nutraceuticals are bioactive compounds isolated from plants and are highly sensitive. Developments in nanotechnology have helped in overcoming various issues associated with the use of bioactive compounds in nutraceuticals and functional food. Depending on the physicochemical properties of the bioactive compound, a number of nanoencapsulation/delivery methods are available that enable protection and stabilize the bioactive compound providing better bioavailability. In this chapter, the developments in nanoformulations used for encapsulating bioactive compounds and their potential in anti-aging medicine are discussed. The most common method is by creating nanoemulsions, which can be used in both food and beverage applications. Nanosafety issues associated with the use of nanomaterials in food, related regulatory policies and consumer attitude are also outlined.

Adjustment of Matrix-Assisted Laser Desorption/Ionization for Glycolipids

Gangliosides isolated from biological sources are usually detected as sodium/potassium adduct ions and these ions are easily fragmented by dissociation of labile glycosidic bonds in the positive ion mode Mass Spectrometry (MS). A large number of conditions for fragment suppression of these acidic glycolipids by using non-acidic matrices or changing metal additions have been demonstrated. Compared to sodium/potassium adduct ions, the cesium adduct ions suppress the fragmentation of these acidic glycolipids. On the contrary, lithium adduct ions induce the fragmentation, but generate more informative fragment ions of glycolipids than other alkali metal adduct ions in post-source decay, MS/MS as well as MS spectra. To suppress the fragmentation of labile glycosidic bond and generate more informative fragmentation, we have examined and established the optimal condition for the detection of [M+Li]+ of gangliosides (GM3 and GM2) using the matrix-assisted laser desorption/ionization time-of-flight MS by adjusting matrix and alkali metal salt combinations and concentrations.

Simple and rapid removal of the interference in gangliosides extracted from HPTLC spot on MALDI-TOF MS analysis

Extraction of thin-layer chromatography (TLC) spot with organic solvents is one of the convenient methods for glycolipid isolation from crude samples, but other background contaminants are also co-extracted during this process. Calcium sulfate (gypsum), starch and synthetic polymers are commonly used as binders in TLC plates, and the co-extracted synthetic polymers usually interfere with further structural analyses, especially in analysis by mass spectrometry (MS). Several column chromatographic processes are therefore used to purify these extracts. However, the purification processes are time consuming and suffer from sample loss. In our previous study, we established a method for detergent removal from glycolipids in a detergent-resistant membrane microdomain (DRM). The procedure is based on selective detergent extraction, in which the sample is dried in a glass tube, followed by washing with non-polar organic solvents, 1,2-dichloroethane (DCE). In this study, we have attempted to apply this method for the background removal from gangliosides and glycosylinositolphosphoceramides extracted from high performance TLC (HPTLC) spots. After DCE washing, these glycolipids were detected by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS, and it was found that DCE washing could effectively remove HPTLC backgrounds.

Curcumin nanoparticles- a gateway for multifaceted approach to tackle Alzheimer's disease

Curcumin is a polyphenolic compound which has been used since ages to treat various ailments. Research in the past few decades has demonstrated its potential therapeutic or preventive effects due to its anti-tumor, anti-inflammatory, anti-oxidative, anti-amyloid, anti-arthritic, anti-ischemic to list a few. In our work, we have successfully synthesized curcumin nanoparticles encapsulated in poly lactic-co-glycolic acid (PLGA) which are water soluble. We would like to harness the anti-amyloid, anti-inflammatory and anti-oxidant activities of curcumin to alleviate the amyloid beta level and other associated changes in Alzheimer disease (AD).