Yung-Chih Kuo

Targeting delivery of etoposide to inhibit the growth of human glioblastoma multiforme using lactoferrin- and folic acid-grafted poly(lactide-co-glycolide) nanoparticles

Lactoferrin (Lf) and folic acid (FA) were crosslinked on poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) for transporting etoposide across the blood-brain barrier (BBB) and treating human brain malignant glioblastoma. Lf- and FA-grafted PLGA NPs (Lf/FA/PLGA NPs) were employed to permeate the monolayer of human brain-microvascular endothelial cells (HBMECs) regulated by human astrocytes and to inhibit the multiplication of U87MG cells. Lf/FA/PLGA NPs showed a satisfactory entrapment efficiency of etoposide and characteristics of sustained drug release. When compared with PLGA NPs, the permeability coefficient for etoposide across the BBB using Lf/FA/PLGA NPs increased about twofold. The antiproliferative efficacy against the growth of U87MG cells was in the following order: Lf/FA/PLGA NPs>FA/PLGA NPs>PLGA NPs>free etoposide solution. In addition, the targeting ability of Lf/FA/PLGA NPs was evidenced by immunostaining of Lf receptor on HBMECs and folate receptor on U87MG cells during endocytosis. Lf/FA/PLGA NPs with loaded etoposide can be a promising anticancer pharmacotherapy to enhance the delivery of etoposide to malignant brain tumors for preclinical trials.

Entrapment and release of saquinavir using novel cationic solid lipid nanoparticles.

Cationic solid lipid nanoparticles (CSLNs) with entrapped saquinavir (SQV) were fabricated by microemulsion method. Here, CSLNs were stabilized by polysorbate 80, and the lipid phase contained cationic stearylamine (SA) and dioctadecyldimethyl ammonium bromide (DODAB) and nonionic Compritol 888 ATO (CA) and cacao butter (CB). Properties of the present pharmaceutical formulations including the entrapment efficiency, the release kinetics, and the distribution of SQV in CSLNs were analyzed. The results indicated that a mixture of SA and DODAB and a mixture of CA and CB were beneficial to the entrapment efficiency of SQV. However, an increase in the content of cationic lipids insignificantly affected the entrapment efficiency of SQV when the weight percentage of SA and DODAB was greater than 1% during emulsification. Also, the rate of SQV released from CSLNs with lipid cores of a mixture of CA and CB was slower than that of pure CB. The temporal variation in the released SQV suggested that the carriers could be sustained delivery systems with no apparent initial burst. Hence, the current CSLNs could carry SQV for the improved medication of individuals infected by human immunodeficiency viruses.

Transport of saquinavir across human brain-microvascular endothelial cells by poly(lactide-co-glycolide) nanoparticles with surface poly-(γ-glutamic acid)

Poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) with surface poly-(γ-glutamic acid) (γ-PGA) were applied to enhance the transport of saquinavir (SQV) across the blood-brain barrier (BBB). PLGA NPs encapsulated SQV and grafted with γ-PGA to form drug carriers (γ-PGA/SQV-PLGA NPs) for crossing through a monolayer of human brain-microvascular endothelial cells (HBMECs) regulated with human astrocytes. The results revealed that a lower molecular weight of γ-PGA yielded a higher grafting efficiency of γ-PGA on PLGA NPs. In addition, γ-PGA with a low molecular weight accelerated the dissolution of SQV from γ-PGA/SQV-PLGA NPs. A higher grafting efficiency (more didecyl dimethylammonium bromide) and a lower molecular weight of γ-PGA increased the permeability of SQV across the BBB, in general. When the grafting efficiency was 85.2% at 6kDa of γ-PGA, γ-PGA/SQV-PLGA NPs reached about 6 times the permeability of free SQV (the maximal permeability). γ-PGA could also promote the endocytosis of NPs and expression of ornithine decarboxylase by HBMECs. γ-PGA/SQV-PLGA NPs are efficacious nanoparticulate carriers in delivering antiretroviral drug across the BBB.

Delivering etoposide to the brain using catanionic solid lipid nanoparticles with surface 5-HT-moduline

Brain-targeted delivery of etoposide (ETP) is important for treating malignant tumors in the central nervous system. This study presents the transport of ETP across the blood-brain barrier (BBB) using catanionic solid lipid nanoparticles (CASLNs) grafted with 5-HT-moduline. ETP-encapsulated CASLNs (ETP-CASLNs) were prepared in catanionic microemulsion and constructed into solid colloids by rapid cooling. In addition, the uptake of 5-HT-moduline-grafted ETP-CASLNs (5-HT-moduline/ETP-CASLNs) by human brain-microvascular endothelial cells (HBMECs) was visualized by immunochemical staining. We found that a maximal entrapment efficiency of ETP occurred at 0.75 mM of catanionic surfactants. An increase in the concentration of catanionic surfactants reduced the viability of HBMECs. Moreover, an increase in the concentration of 5-HT-moduline reduced the grafting efficiency of 5-HT-moduline, cell viability, and transendothelial electrical resistance of HBMEC monolayer, and enhanced the permeability of propidium iodide and ETP across the BBB. Surface-modified 5-HT-moduline/ETP-CASLNs can be promising drug delivery carriers for anti-brain tumor chemotherapy in preclinical trial.

Brain targeted delivery of carmustine using solid lipid nanoparticles modified with tamoxifen and lactoferrin for antitumor proliferation.

Solid lipid nanoparticles (SLNs) conjugated with tamoxifen (TX) and lactoferrin (Lf) were applied to carry anticancer carmustine (BCNU) across the blood-brain barrier (BBB) for enhanced antiproliferation against glioblastoma multiforme (GBM). BCNU-loaded SLNs with modified TX and Lf (TX-Lf-BCNU-SLNs) were used to penetrate a monolayer of human brain-microvascular endothelial cells (HBMECs) and human astrocytes and to target malignant U87MG cells. The surface TX and Lf on TX-Lf-BCNU-SLNs improved the characteristics of sustained release for BCNU. When compared with BCNU-loaded SLNs, TX-Lf-BCNU-SLNs increased the BBB permeability coefficient for BCNU about ten times. In addition, TX-BCNU-SLNs considerably promoted the fluorescent intensity of intracellular acetomethoxy derivative of calcein (calcein-AM) in HBMECs via endocytosis. However, the conjugated Lf could only slightly increase the fluorescence of calcein-AM. Moreover, the order of formulation in the inhibition to U87MG cells was TX-Lf-BCNU-SLNs>TX-BCNU-SLNs>Lf-BCNU-SLNs>BCNU-SLNs. TX-Lf-BCNU-SLNs can be effective in infiltrating the BBB and delivering BCNU to GBM for future chemotherapy application.

Cardiolipin-incorporated liposomes with surface CRM197 for enhancing neuronal survival against neurotoxicity

CRM197-grafted liposomes containing cardiolipin (CL) (CRM197/CL-liposomes) were used to enhance the permeability of neuron growth factor (NGF) across the blood-brain barrier (BBB) for promoting the neuroprotective effect of NGF. CRM197/CL-liposoms were incubated with a monolayer of human astrocyte (HA)-regulated human brain-microvascular endothelial cells (HBMECs) and employed to rescue SK-N-MC cells with insult of fibrillar β-amyloid peptide (1-42) (Aβ1-42). An increase in the CL mole percentage enhanced the particle size, absolute value of zeta potential, NGF entrapment efficiency, CRM197 grafting efficiency, viability of HBMECs, HAs, and SK-N-MC cells, and BBB permeability of propidium iodide (PI) and NGF, and reduced the transendothelial electrical resistance (TEER). In addition, an increase in the CRM197 weight percentage increased the particle size, absolute value of zeta potential, viability of HBMECs and HAs, and BBB permeability of PI and NGF, and decreased the CRM197 grafting efficiency and TEER. CRM197/CL-liposomes have the ability to target the BBB and to reduce neurotoxicity of Aβ142 and can be promising formulations for treating Alzheimers disease in future medicinal application.

Nerve growth factor-loaded heparinized cationic solid lipid nanoparticles for regulating membrane charge of induced pluripotent stem cells during differentiation

Nerve growth factor (NGF)-loaded heparinized cationic solid lipid nanoparticles (NGF-loaded HCSLNs) were developed using heparin-stearic acid conjugate, cacao butter, cholesterol, stearylamine (SA), and esterquat 1 (EQ 1). The effect of cationic lipids and lipid matrix composition on the particle size, particle structure, surface molecular composition, chemical structure, electrophoretic mobility, and zeta potential of HCSLNs was investigated. The effect of HCSLNs on the membrane charge of induced pluripotent stem cells (iPSCs) was also studied. The results indicated that the average diameter of HCSLNs was 90-240nm and the particle size of HCSLNs with EQ 1 was smaller than that with SA. The zeta potential and electrophoresis analysis showed that HCSLNs with SA had a positively charged potential and HCSLNs with EQ 1 had a negatively charged potential at pH7.4. The high-resolution transmission electron microscope confirmed the loading of NGF on the surface of HCSLNs. Differentiation of iPSCs using NGF-loaded HCSLNs with EQ 1 exhibited higher absolute values of the electrophoretic mobility and zeta potential than differentiation using NGF-loaded HCSLNs with SA. The immunochemical staining of neuronal nuclei revealed that NGF-loaded HCSLNs can be used for differentiation of iPSCs into neurons. NGF-loaded HCSLNs with EQ 1 had higher viability of iPSCs than NGF-loaded HCSLNs with SA. NGF-loaded HCSLNs with EQ 1 may be promising formulation to regulate the membrane charge of iPSCs during neuronal differentiation.

Targeted delivery of rosmarinic acid across the blood–brain barrier for neuronal rescue using polyacrylamide-chitosan-poly(lactide-co-glycolide) nanoparticles with surface cross-reacting material 197 and apolipoprotein E

Rosmarinic acid-loaded polyacrylamide-chitosan-poly(lactide-co-glycolide) nanoparticles (RA-PAAM-CH-PLGA NPs) were grafted with cross-reacting material 197 (CRM197) and apolipoprotein E (ApoE) for targeting of the blood-brain barrier (BBB) and rescuing degenerated neurons. The polymeric nanocarriers were prepared by microemulsion, solvent diffusion, grafting, and surface modification, and CRM197-ApoE-RA-PAAM-CH-PLGA NPs were used to treat human brain-microvascular endothelial cells, RWA264.7 cells, and Aβ-insulted SK-N-MC cells. Experimental results revealed that an increase in the weight percentage of PAAM decreased the particle size, zeta potential, and grafting efficiency of CRM197 and ApoE. In addition, surface DSPE-PEG(2000) could protect CRM197-ApoE-RA-PAAM-CH-PLGA NPs against uptake by RWA264.7 cells. An increase in the concentration of CRM197 and ApoE decreased the transendothelial electrical resistance and increased the ability of propidium iodide and RA to cross the BBB. The order in the viability of apoptotic SK-N-MC cells was CRM197-ApoE-RA-PAAM-CH-PLGA NPs > CRM197-RA-PAAM-CH-PLGA NPs > RA. Thus, CRM197-ApoE-RA-PAAM-CH-PLGA NPs can be a promising formulation to deliver RA to Aβ-insulted neurons in the pharmacotherapy of Alzheimers disease.

Pancreatic differentiation of induced pluripotent stem cells in activin A-grafted gelatin-poly(lactide-co-glycolide) nanoparticle scaffolds with induction of LY294002 and retinoic acid

The differentiation of induced pluripotent stem cells (iPSCs) in biomaterial scaffolds is an emerging area for biomedical applications. This study proposes, for the first time, the production of pancreatic cells from iPSCs in gelatin-poly(lactide-co-glycolide) nanoparticle (PLGA NP) scaffolds. The porosity and swelling ratio of the scaffolds decreased with increases in gelatin and PLGA NP concentrations. The adhesion efficiency of iPSCs in gelatin-PLGA NP scaffolds was found to be higher at 6.7% (w/w) PLGA NP. A 3-step induction of iPSCs was used to differentiate into pancreatic islet cells using activin A, 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002), and retinoic acid (RA). The ability of iPSCs to differentiate into pancreatic islet cells in a scaffold was demonstrated by immunofluorescence staining and flow-cytometry analysis. The results indicate that the concentration of activin A, LY294002, and RA plays a decisive role in the differentiation of iPSCs into pancreatic cells. Activin A and LY294002 induce the iPSCs into endoderm and RA induces endoderm into islet cells. A maximum insulin secretion by glucose stimulation was obtained with a higher concentration (2μM) of RA. The use of activin A-grafted gelatin-PLGA NP scaffolds induced by LY294002 and RA can be a promising approach to developing pancreatic islet cells from iPSCs.

Rosmarinic acid and curcumin-loaded polyacrylamide-cardiolipin-poly(lactide-co-glycolide) nanoparticles with conjugated 83-14 monoclonal antibody to protect β-amyloid-insulted neurons

Polymeric nanoparticles (NPs) combined with lipids can have profound effects on treatment efficacy in patients with neurological disorders such as Alzheimers disease (AD). We developed polyacrylamide (PAAM)-cardiolipin (CL)-poly(lactide-co-glycolide) (PLGA) NPs grafted with surface 83-14 monoclonal antibody (MAb) to carry rosmarinic acid (RA) and curcumin (CUR). This drug delivery system was used to cross the blood-brain barrier (BBB) and enhance the viability of SK-N-MC cells insulted with β-amyloid (Aβ) deposits. Experimental evidence revealed that an increase in the concentration of 83-14 MAb enhanced the permeability coefficient of RA and CUR using the nanocarriers. The levels of phosphorylated p38 and phosphorylated tau protein at serine 202 in degenerated SK-N-MC cells were in the order: Aβu202f>u202f(Aβu202f+u202fRA-CUR)u202f>u202f(Aβu202f+u202f83-14 MAb-RA-CUR-PAAM-PLGA NPs)u202f>u202f(Aβu202f+u202f83-14 MAb-RA-CUR-PAAM-CL-PLGA NPs)u202f≈u202fcontrol. The viability of SK-N-MC cells reduced with time and CL in 83-14 MAb-RA-CUR-PAAM-CL-PLGA NPs advantaged Aβ-targeted delivery of RA-CUR. These results evidenced that the current 83-14 MAb-RA-CUR-PAAM-CL-PLGA NPs can be a promising pharmacotherapy to permeate the BBB and reduce the fibrillar Aβ-induced neurotoxicity.