Acute lung injury (ALI) is a lung inflammatory disease for which pulmonary delivery of drug and gene could be a useful strategy. In this study, cholesterol-conjugated polyamidoamine (PAM-Chol) was synthesized and characterized as a carrier for combined delivery of anti-inflammatory gene and drug into the lungs by inhalation. The PAM-Chol formed self-assembled micelles in an aqueous solution with a critical micelle concentration of 0.22 mg ml-1. An in vitro transfection assay to L2 lung epithelial cells showed that the PAM-Chol micelle had higher transfection efficiency than lipofectamine and polyethylenimine (25 kDa, PEI25k). As the anti-inflammatory drug, resveratrol was loaded into the cores of the PAM-Chol micelles using the oil-in-water emulsion/solvent evaporation method. In lipopolysaccharide (LPS)-activated macrophage cells, resveratrol-loaded PAM-Chol (PAM-Chol/Res) reduced pro-inflammatory cytokines, confirming the anti-inflammatory effects of resveratrol. In in vitro transfection assays to L2 cells, the PAM-Chol/Res micelles had transfection efficiency similar to that of PAM-Chol. The delivery of resveratrol or the heme oxygenase-1 gene (pHO-1) by inhalation was evaluated in an ALI animal model. Resveratrol delivery using the PAM-Chol/Res micelles inhibited the nuclear translocation of nuclear factor-κB (NF-κB) and reduced pro-inflammatory cytokines in the lungs. pHO-1 delivery using PAM-Chol induced HO-1 expression and reduced pro-inflammatory cytokines. However, the highest anti-inflammatory effects were obtained with combined delivery of pHO-1 and resveratrol using the pHO-1/PAM-Chol/Res complex, as demonstrated in cytokine assays and immunohistochemical studies. Therefore, the PAM-Chol micelle is an efficient carrier of resveratrol and pHO-1 into the lungs and could be useful for the treatment of ALI by inhalation.

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A self-assembled nanoparticle composed of hypoxia-specific anti-RAGE peptide (HSAP), heme oxygenase-1 plasmid (pHO1), and deoxycholate-conjugated polyethylenimine-2k (DP2k) was developed for ischemic stroke therapy.

A glioblastoma is a common primary brain tumor that expresses microRNA-21 (miR-21), which inhibits the expression of pro-apoptotic genes such as phosphatase and tensin homologue (PTEN) and programmed cell death 4 (PDCD4). Therefore, an antisense-oligonucleotide against miR-21 (miR21ASO) could have therapeutic effects for glioblastomas. In this study, curcumin was loaded into deoxycholic acid-conjugated polyethylenimine (DP) micelles. The curcumin-loaded DP micelle (DP-Cur) was evaluated as a carrier for the combined delivery of curcumin and miR21ASO. Gel retardation and heparin competition assays showed that DP-Cur formed stable complexes with miR21ASO. The anti-tumor effects of the combined delivery of curcumin and miR21ASO were evaluated in C6 glioblastoma cells. In vitro transfection showed that DP-Cur had an miR21ASO delivery efficiency similar to that of polyethylenimine (25 kDa, PEI25k) and DP. In the C6 cells, the delivery of miR21ASO using DP-Cur effectively reduced the miR21 level. The miR21ASO/DP-Cur complex induced apoptosis more effectively than the single delivery of curcumin or miR21ASO. The therapeutic effect of the miR21ASO/DP-Cur complex was also evaluated in an intracranial glioblastoma animal model. The miR21ASO/DP-Cur complex reduced the tumor volume more effectively than single therapy of curcumin or miR21ASO. Immunohistochemistry showed that PDCD4 and PTEN were induced in the miR21ASO/DP and miR21ASO/DP-Cur complex groups. Therefore, DP-Cur is an efficient carrier of miR21ASO and the combined delivery of miR21ASO and curcumin may be useful in the development of combination therapy for glioblastoma.

Introduction The application of gene therapy for a nonlife-threatening disease, such as erectile dysfunction (ED), requires a higher safety level and more efficacious systems for gene transfer. Aim To establish a novel technique for gene expression in a rat model of hypercholesterolemic ED that uses the RTP801 promoter, a hypoxia-inducible promoter. Methods Two-month-old male Sprague–Dawley rats were fed a diet containing 4% cholesterol and 1% cholic acid, and age-matched control animals were fed a normal diet, for 3 months. Main Outcome Measures Cavernous expression of hypoxia-inducible factor (HIF)-1α was evaluated by Western blot. After intracavernous injection of pSV-Luc or pRTP801-Luc, gene expression was evaluated by luciferase assay, and the gene expression area was evaluated by immunohistochemistry. Results HIF-1α was up-regulated in the corpus cavernosum of hypercholesterolemic rats. Although pSV-Luc did not induce gene expression in either the control or the cholesterol group, pRTP801-Luc significantly induced gene expression in the cholesterol group and resulted in higher luciferase activity than did pSV-Luc up to 14 days after injection. Immunohistochemistry showed that the gene expression area was also greater in the pRTP801-Luc group than in the pSV-Luc group, but the difference was not as great as that in luciferase activity. This suggests that pRTP801-Luc exerts its effect mainly by inducing promoter activity under hypoxia, not by increasing the number of transfected cells. Conclusion The RTP801 promoter-driven gene expression system increased gene expression in the corpus cavernosum tissue of rats with cholesterol-induced ED. This may be a useful system for the development of gene therapy in vasculogenic ED.

Pulmonary gene delivery system was developed based on RAGE-antagonist peptide and dexamethasone-conjugated polyamidoamine.

Cell-type-specific genes involved in disease can be effective therapeutic targets; therefore, the development of a cell-type-specific gene delivery system is essential.

Some genetic diseases are associated with the defects of the mitochondrial genome. Direct DNA delivery to the mitochondrial matrix has been suggested as an approach for mitochondrial gene therapy for these diseases. We hypothesized that a mitochondrial leader peptide (LP) conjugated polyethylenimine (PEI) could deliver DNA to the mitochondrial sites. PEI-LP was synthesized by the conjugation of LP to PEI using disulfide bond. The complex formation of PEI-LP with DNA was confirmed by a gel retardation assay. In this study, DNA was completely retarded at a 0.4/1 PEI-LP/DNA weight ratio. In vitro delivery tests into isolated mitochondria or living cells were performed with rhodamin-labeled DNA and PEI-LP. In vitro cell-free delivery assay with isolated mitochondria showed that PEI-LP/DNA complexes were localized at mitochondria sites. Furthermore, the PEL-LP/DNA complexes were localized at the mitochondrial sites in living cells. However, a control carrier, PEI, did not show this effect. In addition, MTT assay showed that PEI-LP showed lower cytotoxicity than PEI. These results suggest that PEI-LP can deliver DNA to the mitochondrial sites and may be useful for the development of mitochondrial gene therapy.