Anowar Hussain

Exosomes secreted under hypoxia enhance invasiveness and stemness of prostate cancer cells by targeting adherens junction molecules

Hypoxic conditions in prostate cancer (PCA) are associated with poor prognosis; however, precise mechanism/s through which hypoxia promotes malignant phenotype remains unclear. Here, we analyzed the role of exosomes from hypoxic PCA cells in enhancing the invasiveness and stemness of naïve PCA cells, as well as in promoting cancer‐associated fibroblast (CAF) phenotype in prostate stromal cells (PrSC). Human PCA LNCaP and PC3 cells were exposed to hypoxic (1% O2) or normoxic (21% O2) conditions, and exosomes secreted under hypoxic (ExoHypoxic) and normoxic (ExoNormoxic) conditions were isolated from conditioned media. Nanoparticle tracking analysis revealed that ExoHypoxic have smaller average size as compared to ExoNormoxic. Immunoblotting results showed a higher level of tetraspanins (CD63 and CD81), heat shock proteins (HSP90 and HSP70), and Annexin II in ExoHypoxic compared to ExoNormoxic. Co‐culturing with ExoHypoxic increased the invasiveness and motility of naïve LNCaP and PC3 cells, respectively. ExoHypoxic also promoted prostasphere formation by both LNCaP and PC3 cells, and enhanced α‐SMA (a CAF biomarker) expression in PrSC. Compared to ExoNormoxic, ExoHypoxic showed higher metalloproteinases activity and increased level of diverse signaling molecules (TGF‐β2, TNF1α, IL6, TSG101, Akt, ILK1, and β‐catenin). Furthermore, proteome analysis revealed a higher number of proteins in ExoHypoxic (160 proteins) compared to ExoNormoxic (62 proteins), primarily associated with the remodeling of epithelial adherens junction pathway. Importantly, ExoHypoxic targeted the expression of adherens junction proteins in naïve PC3 cells. These findings suggest that ExoHypoxic are loaded with unique proteins that could enhance invasiveness, stemness, and induce microenvironment changes; thereby, promoting PCA aggressiveness.

Preparation and evaluation of the effect of particle size on the properties of chitosan-montmorillonite nanoparticles loaded with isoniazid

In this report, efforts have been made to develop isoniazid loaded chitosan-montmorillonite nanoparticles by ionic gelation of chitosan with pentasodium tripolyphosphate. The nanoparticles have been characterized by FTIR, XRD, SEM and TEM. The effect of surfactant and particle size on chitosan nanoparticles have been assessed with regard to swelling, encapsulation efficiency and release of isoniazid in different mediums. Swelling experiments provide important information on drug diffusion properties, which indicates that the chitosan nanoparticles are highly sensitive to the pH environment. The drug release mechanism has been studied during different time periods using a UV-visible spectrophotometer. Cytotoxicity has been assessed by MTT assay analysis. Mucoadhesion properties have been appraised by an in vitro wash off test and an ex vivo mucoadhesion test. The results imply that chitosan-montmorillonite nanoparticles can be exploited as potential drug carriers for controlled-release applications.

Graviola inhibits hypoxia-induced NADPH oxidase activity in prostate cancer cells reducing their proliferation and clonogenicity

Prostate cancer (PCa) is the leading malignancy among men. Importantly, this disease is mostly diagnosed at early stages offering a unique chemoprevention opportunity. Therefore, there is an urgent need to identify and target signaling molecules with higher expression/activity in prostate tumors and play critical role in PCa growth and progression. Here we report that NADPH oxidase (NOX) expression is directly associated with PCa progression in TRAMP mice, suggesting NOX as a potential chemoprevention target in controlling PCa. Accordingly, we assessed whether NOX activity in PCa cells could be inhibited by Graviola pulp extract (GPE) that contains unique acetogenins with strong anti-cancer effects. GPE (1–5 μg/ml) treatment strongly inhibited the hypoxia-induced NOX activity in PCa cells (LNCaP, 22Rv1 and PC3) associated with a decrease in the expression of NOX catalytic and regulatory sub-units (NOX1, NOX2 and p47phox). Furthermore, GPE-mediated NOX inhibition was associated with a strong decrease in nuclear HIF-1α levels as well as reduction in the proliferative and clonogenic potential of PCa cells. More importantly, GPE treatment neither inhibited NOX activity nor showed any cytotoxicity against non-neoplastic prostate epithelial PWR-1E cells. Overall, these results suggest that GPE could be useful in the prevention of PCa progression via inhibiting NOX activity.

Study on crosslinked gelatin-montmorillonite nanoparticles for controlled drug delivery applications

Gelatin, because of its biodegradability and ecofriendly nature, has been the best choice for controlled release applications. Montmorillonite (MMT) clay shows a very important role in controlling drug delivery. Hence, an attempt was made in this work to prepare gelatin–MMT nanoparticles by desolvation method using acetone as precipitating agent, glutaraldehyde (GA) as crosslinking agent, and water as reaction media for controlled delivery of isoniazid, a drug for tuberculosis. Characterization of the MMT and isoniazid-loaded gelatin–MMT nanoparticles was carried out using Fourier transform infrared spectroscopy, X-ray diffraction study, scanning electron microscopy study, and transmission electron microscopy study. The effect of MMT on gelatin nanoparticles was evaluated in terms of water uptake studies, and subsequently to the release of isoniazid drug in buffer solution at pH 1.2 (gastric pH) and pH 7.4 (intestinal pH). Swelling experiment indicated that the gelatin nanoparticles were very sensitive to the pH environment. The release profile of drug was studied by a UV–Visible spectrophotometer. Cytotoxicity study revealed that MMT-containing nanoparticles showed less cytotoxicity than MMT-free nanoparticles.

Soy flour nanoparticles for controlled drug delivery: effect of crosslinker and montmorillonite (MMT)

Soy flour (SF)–Montmorillonite (MMT) nanoparticles crosslinked with glutaraldehyde (GA) have been made and used as a carrier for isoniazid. The nanoparticles have been characterized by fourier transmission infra-red spectroscopy (FTIR), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and transmission emission microscopy (TEM). The effects of MMT and glutaraldehyde on the nanoparticles have been assessed with regard to swelling, encapsulation efficiency and consequently, the release of isoniazid in different mediums. The drug release mechanism has been studied for different time periods by UV-Vis spectroscopy. Cytotoxicity testing has been performed by MTT assay analysis. The results imply that the nanoparticles can be exploited as a potential drug carrier for controlled release applications.

Carboxymethyl starch-chitosan-coated iron oxide magnetic nanoparticles for controlled delivery of isoniazid

Abstract Context: The coating material of magnetic nanoparticles plays a great role in drug delivery application. The coatings not only increase the stability of the nanoparticles but also improve the drug release pattern, biocompatibility and mucoadhesivity. Objective: Montmorillonite (MMT) containing magnetic iron oxide nanoparticles coated with polyelectrolyte complex (PEC) of carboxymethyl starch-chitosan were prepared for controlled release applications. Method: The PEC-coated nanoparticles were characterised by Fourier Transmission Infra-red spectroscopy and X-ray diffraction, scanning electron microscope, transmission electron microscope, and dynamic light scattering. Cytotoxicity study was performed by MTT assay analysis. Mucoadhesivity test was performed by using in vitro wash off and ex vivo method. Result: The coating of PEC showed good stability, biocompatibility and mucoadhesivity of the iron oxide magnetic nanoparticles. MMT addition enhanced the swelling, drug loading and release and also the cytotoxicity and mucoadhesivity of the nanoparticles. Conclusion: This study revealed that the MMT incorporated PEC of CMS-CS can be effectively used for coating of iron oxide nanoparticles.

Physical and biophysical assessment of highly fluorescent, magnetic quantum dots of a wurtzite-phase manganese selenide system

Combining fluorescence and magnetic features in a non-iron based, select type of quantum dots (QDs) can have immense value in cellular imaging, tagging and other nano-bio interface applications, including targeted drug delivery. Herein, we report on the colloidal synthesis and physical and biophysical assessment of wurtzite-type manganese selenide (MnSe) QDs in cell culture media. Aiming to provide a suitable colloidal system of biological relevance, different concentrations of reactants and ligands (e.g., thioglycolic acid, TGA) have been considered. The average size of the QDs is ∼7 nm, which exhibited a quantum yield of ∼75% as compared to rhodamine 6 G dye(®). As revealed from time-resolved photoluminescence (TR-PL) response, the near band edge emission followed a bi-exponential decay feature with characteristic times of ∼0.64 ns and 3.04 ns. At room temperature, the QDs were found to exhibit paramagnetic features with coercivity and remanence impelled by TGA concentrations. With BSA as a dispersing agent, the QDs showed an improved optical stability in Dulbeccos Modified Eagle Media(®) (DMEM) and Minimum Essential Media(®) (MEM), as compared to the Roswell Park Memorial Institute(®) (RPMI-1640) media. Finally, the cell viability of lymphocytes was found to be strongly influenced by the concentration of MnSe QDs, and had a safe limit upto 0.5 μM. With BSA inclusion in cell media, the cellular uptake of MnSe QDs was observed to be more prominent, as revealed from fluorescence imaging. The fabrication of water soluble, nontoxic MnSe QDs would open up an alternative strategy in nanobiotechnology, while preserving their luminescent and magnetic properties intact.

Flower extract of Nyctanthes arbor-tristis modulates glutathione level in hydrogen peroxide treated lymphocytes

Background: Nyctanthes arbor-tristis Linn (Oleaceae) is a well-known traditional medicinal plant used throughout the India as an herbal remedy for treating various infectious and non-infectious diseases. Objective: To evaluate the antioxidative activity of hydro-alcoholic extract of flower in the lymphocytes exposed to oxidative stress induced by H2O2 . Materials and Methods: Isolated lymphocytes were treated in vitro with extract or extract+H2O2, and the level of reduced glutathione (GSH) as well as the activity of glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) were measured. Results: Treatment of lymphocyte with flower extract (50, 100, and 200 μg/ ml) significantly increased the level of GSH and decreased the activity of GST. The LDH activity measured in the cell-free medium decreased significantly. Pre-treatment of lymphocyte with flower extract protects the lymphocyte from the H2O2 induced oxidative stress by significantly increasing the levels of GSH as compared to the cells treated only with H2O2. Pre-treatment also reduced the activity of LDH significantly as compared to the cells treated only with H2O2. The LDH activity in cell-free medium is associated with membrane damage, the decreased levels of LDH activity reflects the reduced level of membrane damage due to H2O2. Conclusion: The present findings suggest the protective role of the hydro-alcoholic extracts of the flower of Nyctanthes arbor-tristis against membrane damage induced by H2O2. The results also suggest that the extract might be rich in phytochemicals with antioxidant/radical scavenging potentials, which might find application in antioxidant therapy.

Genipin crosslinked Curcumin loaded Chitosan/Montmorillonite K-10 (MMT) nanoparticles for controlled drug delivery applications

Abstract Here, we have reported the influence of MMT and genipin in releasing curcumin from the Genipin crosslinked Chitosan/MMT nanoparticles, prepared by ionic gelation method. The nanoparticles were characterised using Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). Zeta potential and average diameter of the nanoparticles were found in the range 32–47 mV and 430–560 nm. Swelling and release of curcumin from the nanoparticles increased with the decrease in pH of the medium, MMT, and genipin content. Curcumin released from the nanoparticles reduced the viability of MCF-7 and Hep G2 cells as compared to untreated cells. The nanoparticles increased the level of reduced glutathione (GSH), superoxide dismutase (SOD), and catalase level in human PBMCs and decreased the level of Lipid peroxidation suggesting an enhanced protection against cellular damage. Lower pH and higher MMT concentration in the nanoparticles improved the mucoadhesive properties.

Isoniazid loaded gelatin-cellulose whiskers nanoparticles for controlled drug delivery applications

AbstractNatural polymers like gelatin have been used as a potential drug carrier for controlled delivery applications due to their various advantages over synthetic polymers. Cellulose Whiskers (CWs) have the capacity to form strong hydrogen bonds which help in controlling the release of drug and also provide good strength to the drug carrier. In this report, CWs were prepared from filter paper cellulose by acid hydrolysis. Also, attempt was made to prepare gelatin-CWs nanoparticles by desolvation method using an anti-tuberculosis drug, isoniazid and a crosslinker glutaraldehyde (GA). The CWs and gelatin-CWs nanoparticles were characterized by X-ray diffractometry (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The effect of CWs on gelatin nanoparticles over 8-hour period was measured in swelling studies. Efficiency of drug loading and subsequent release of isoniazid in buffer solutions at pH 1.2 (0.1N HCl) and pH 7.4 (phosphate buffer) were studied. Cytotoxicity study showed less toxicity for gelatin-CWs nanoparticles. Graphical AbstractIsoniazid loaded gelatin-Cellulose Whisker nanoparticles were prepared by desolvation method and were characterized by X-ray diffractometry, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and Transmission Electron Microscopy. The nanoparticles have potential applications in the field of controlled drug delivery.