Nanotized Curcumin and Miltefosine, a Potential Combination for Treatment of Experimental Visceral Leishmaniasis.

Leishmaniasis chemotherapy remains very challenging due to high cost of the drug and its associated toxicity and drug resistance, which develops over a period of time. Combination therapies (CT) are now in use to treat many diseases, such as cancer and malaria, since it is more effective and affordable than monotherapy. CT are believed to represent a new explorable strategy for leishmaniasis, a neglected tropical disease caused by the obligate intracellular parasite Leishmania In the present study, we investigated the effect of a combination of a traditional Indian medicine (ayurveda), a natural product curcumin and miltefosine, the only oral drug for visceral leishmaniasis (VL) using a Leishmania donovani-hamster model. We developed an oral nanoparticle-based formulation of curcumin. Nanoformulation of curcumin alone exhibited significant leishmanicidal activity both in vitro and in vivo In combination with miltefosine, it exhibited a synergistic effect on both promastigotes and amastigotes under in vitro conditions. The combination of these two agents also demonstrated increased in vivo leishmanicidal activity accompanied by increased production of toxic reactive oxygen/nitrogen metabolites and enhanced phagocytic activity. The combination also exhibited increased lymphocyte proliferation. The present study thus establishes the possible use of nanocurcumin as an adjunct to antileishmanial chemotherapy.

Pro-inflammatory macrophage polarization enhances the anti-cancer efficacy of self-assembled galactomannan nanoparticles entrapped with hydrazinocurcumin.

Galactomannan (GM), a natural polymer, is recognized to specifically target macrophage mannose receptors (CD206). Interestingly, some reports indicate that GM has an ability to induce pro-inflammatory (M1-like, tumericidal) polarization in macrophages, suggesting its potential use as an anti-cancer agent. Hydrazinocurcumin (HC), a pyrazole derivative of curcumin, is reported to possess increased anti-cancer efficacy over curcumin. Moreover, HC-encapsulated nanoparticles (NPs) have been reported to re-polarize tumor-associated macrophages (TAMs) from anti-inflammatory (M2-like, tumor-promoting) to pro-inflammatory phenotype. To club the therapeutic properties of both GM and HC, we synthesized self-assembled amphiphilic PEGylated GM NPs loaded with HC (PSGM-HCNPs) and evaluated their potential to re-polarize TAMs towards M1-like phenotype. PSGM-HCNPs re-polarized IL-4 polarized RAW 264.7 cells via a phenotypic switch from M2- to M1-like by elevating ROS level, decreasing CD206 and arginase-1 expressions and increasing pro-inflammatory cytokines' secretion. Conditioned medium (CM) taken from re-polarized RAW 264.7 cells containing residual PSGM-HCNPs elevated ROS, arrested cell cycle, and induced apoptosis in 4T1, breast cancer cells, and Ehrlich's ascites carcinoma (EAC) cells. Decreased levels of MMP-2, MMP-9, and Bcl-2 with increased levels of Bax in both 4T1 and EAC cells indicated anti-metastatic and apoptosis-inducing potential of the CM. Treatment of PSGM-HCNPs in EAC-bearing mice reduced tumor burden, increased their survival time, decreased CD206+F4/80+ cells, and increased TNF-α+F4/80+ cells signifying decrease in M2- and increase in M1-like skewness among ascitic TAMs.

Hyaluronic acid-grafted PLGA nanoparticles for the sustained delivery of berberine chloride for an efficient suppression of Ehrlich ascites tumors.

To promote the specific targeting and elimination of CD44-positive cancer cells, berberine chloride (BRB)-encapsulated hyaluronic acid-grafted poly(lactic-co-glycolic acid) copolymer (BRB-d(HA)-g-PLGA) nanoparticles (NPs) were prepared. The targeted action of these NPs was compared to non-targeted BRB-loaded PLGA NPs and bulk BRB. The in vitro studies demonstrated faster release of BRB and increased cytotoxicity of BRB-d(HA)-g-PLGA NPs in Hela and MCF-7 cells in comparison to BRB-PLGA NPs and bulk BRB. The uptake of BRB-d(HA)-g-PLGA NPs was increased in case of MCF-7 cells as compared to HeLa cells owing to the higher expression of CD44 receptors on MCF-7 cells. The CD44 receptor-mediated uptake of these NPs was confirmed through competitive inhibition experiments. The in vitro results were further validated in vivo in Ehrlich Ascites Carcinoma (EAC)-bearing mice. EAC-bearing mice were injected intravenously with these NPs and the results obtained were compared with that of BRB-PLGA NPs and bulk BRB. BRB-d(HA)-g-PLGA NPs were found to significantly enhance apoptosis, sub-G1 content, life span, mean survival time, and ROS levels in EAC cells with subsequent decrease in mitochondrial membrane potential and tumor burden ion tumor-bearing mice. Taking into account the findings of in vitro and in vivo studies, the enhanced and targeted anti-tumor activity of HA-grafted PLGA copolymer-encapsulated NPs of BRB cannot be negated. Therefore, HA-grafted nanoparticle-based delivery of BRB may offer a promising and improved alternative for anti-tumor therapy.

Trans-blood brain barrier delivery of dopamine-loaded nanoparticles reverses functional deficits in parkinsonian rats.

Sustained and safe delivery of dopamine across the blood brain barrier (BBB) is a major hurdle for successful therapy in Parkinson's disease (PD), a neurodegenerative disorder. Therefore, in the present study we designed neurotransmitter dopamine-loaded PLGA nanoparticles (DA NPs) to deliver dopamine to the brain. These nanoparticles slowly and constantly released dopamine, showed reduced clearance of dopamine in plasma, reduced quinone adduct formation, and decreased dopamine autoxidation. DA NPs were internalized in dopaminergic SH-SY5Y cells and dopaminergic neurons in the substantia nigra and striatum, regions affected in PD. Treatment with DA NPs did not cause reduction in cell viability and morphological deterioration in SH-SY5Y, as compared to bulk dopamine-treated cells, which showed reduced viability. Herein, we report that these NPs were able to cross the BBB and capillary endothelium in the striatum and substantia nigra in a 6-hydroxydopamine (6-OHDA)-induced rat model of PD. Systemic intravenous administration of DA NPs caused significantly increased levels of dopamine and its metabolites and reduced dopamine-D2 receptor supersensitivity in the striatum of parkinsonian rats. Further, DA NPs significantly recovered neurobehavioral abnormalities in 6-OHDA-induced parkinsonian rats. Dopamine delivered through NPs did not cause additional generation of ROS, dopaminergic neuron degeneration, and ultrastructural changes in the striatum and substantia nigra as compared to 6-OHDA-lesioned rats. Interestingly, dopamine delivery through nanoformulation neither caused alterations in the heart rate and blood pressure nor showed any abrupt pathological change in the brain and other peripheral organs. These results suggest that NPs delivered dopamine into the brain, reduced dopamine autoxidation-mediated toxicity, and ultimately reversed neurochemical and neurobehavioral deficits in parkinsonian rats.