Yoonjeong Jang

Target-specific near-IR induced drug release and photothermal therapy with accumulated Au/Ag hollow nanoshells on pulmonary cancer cell membranes.

Au/Ag hollow nanoshells (AuHNSs) were developed as multifunctional therapeutic agents for effective, targeted, photothermally induced drug delivery under near-infrared (NIR) light. AuHNSs were synthesized by galvanic replacement reaction. We further conjugated antibodies against the epidermal growth factor receptor (EGFR) to the PEGylated AuHNS, followed by loading with the antitumor drug doxorubicin (AuHNS-EGFR-DOX) for lung cancer treatment. AuHNSs showed similar photothermal efficiency to gold nanorods under optimized NIR laser power. The targeting of AuHNS-EGFR-DOX was confirmed by light-scattering images of A549 cells, and doxorubicin release from the AuHNSs was evaluated under low pH and NIR-irradiated conditions. Multifunctional AuHNS-EGFR-DOX induced photothermal ablation of the targeted lung cancer cells and rapid doxorubicin release following irradiation with NIR laser. Furthermore, we evaluated the effectiveness of AuHNS-EGFR-DOX drug delivery by comparing two drug delivery methods: receptor-mediated endocytosis and cell-surface targeting. Accumulation of the AuHNS-EGFR-DOX on the cell surfaces by targeting EGFR turned out to be more effective for lung cancer treatments than uptake of AuHNS-EGFR-DOX. Taken together, our data suggest a new and optimal method of NIR-induced drug release via the accumulation of targeted AuHNS-EGFR-DOX on cancer cell membranes.

Chlorpyrifos induces NLRP3 inflammasome and pyroptosis/apoptosis via mitochondrial oxidative stress in human keratinocyte HaCaT cells.

Chlorpyrifos (CPF) has been widely used around the world as a pesticide for both agricultural and residential application. Although various studies have reported toxicity and health-related effects from CPF exposure, the molecular mechanism of CPF toxicity to skin has not been well-characterized. The present study determined the potential mechanism involved in skin toxicity of CPF using the HaCaT human skin keratinocyte cell line. After treating to HaCaT cells, CPF triggered reactive oxygen species (ROS) generation and mitochondrial oxidative stress. We focused on NLRP3 inflammasome, known to induce innate immune response. We used mitochondrial ROS (mROS) scavenger mitoTEMPO to demonstrate a role for mROS in NLRP3 inflammasome and programmed cell death induced by CPF. Our results showed that CPF provoked NLRP3 inflammasome and pyroptosis/apoptosis via an increase of mROS in HaCaT cells. This study proposes that CPF induces innate immune response and skin inflammation through activating the NLRP3 inflammasome in skin epithelial cells. CPF may lead to cutaneous disease conditions and antioxidants could be proposed for therapy against skin exposure to CPF.

A novel potential biocompatible hyperbranched polyspermine for efficient lung cancer gene therapy

The clinical successful application of gene therapy critically depends upon the development of non-toxic and efficient delivery system. Although polycationic non-viral vectors hold great promise in nanomedicine, the exploring of application in clinics still remains a big challenge. To develop a non-toxic and efficient non-viral gene delivery system, two kinds of endogenous substance, citric acid (CA) and spermine (SPE), were used to prepare a new low charge density hyperbranched polyspermine (HPSPE) by one-pot polymerization. The biocompatibility evaluated by hemolytic activity and red blood cell (RBC) aggregation indicated that HPSPE was highly biocompatible without causing hemolysis and RBC aggregation compared with PEI as well as SPE. The MTS assay also demonstrated that the cell viability of HPSPE was above 90% even at 200 μg/mL at different time (24 and 72 h), which much higher than PEI 25K. Besides, HPSPE showed high transfection efficiency without any toxic effect after aerosol delivery to the mice. Moreover, aerosol delivery of HPSPE/Akt1 shRNA significantly reduced tumor size and numbers and efficiently suppressed lung tumorigenesis ultimately in K-ras(LA1) lung cancer model mice. These results suggest that low charge density as well as endogenous substance skeleton endow HPSPE with great potential for toxicity-free and efficient gene therapy.

Towards a Strategic Approaches in Alternative Tests for Pesticide Safety

Pesticides have provided significant benefits including plant disease control and increased crop yields since people developed and utilized them. However, pesticide use is associated with many adverse effects, which necessitate precise toxicological tests and risk assessment. Most of these methods are based on animal studies, but considerations of animal welfare and ethics require the development of alternative methods for the evaluation of pesticide toxicity. Although the usage of laboratory animals is inevitable in scientific evaluation and alternative approaches have limitations in the whole coverage, continuous effort is necessary to minimize animal use and to develop reliable alternative tests for pesticide evaluation. This review discusses alternative approaches for pesticide toxicity tests and hazard evaluation that have been used in peer-reviewed reports and could be applied in future studies based on the critical animal research principles of reduction, replacement, and refinement.

Local Delivery of CTGF siRNA with Poly(sorbitol-co-PEI) Reduces Scar Contraction in Cutaneous Wound Healing

Healing process in scarring inevitably produces a considerable amount of non-organized dense collagen-rich matrix called scar thus impairing the native structure of skin. Connective tissue growth factor (CTGF) overexpression within healing tissues is known to play an imperative role in collagen production stimulated by transforming growth factor-beta in cutaneous wound healing. Undoubtedly, the knockdown of CTGF expression through siRNA-mediated gene silencing could simply impede the scarring process. However, the less stability and low transfection of siRNAs themselves urge a safe carrier to protect and transfect them into cells at a high rate avoiding toxicities. Here, we developed a degradable poly(sorbitol-co-PEI) (PSPEI), prepared by polymerization of sorbitol diacrylate with low molecular weight polyethylenimine, which has high transfection efficiency but low cytotoxicity, and utilized it in siCTGF delivery to silence the expression of CTGF in an animal model of cutaneous wound healing. Unlike contracted scar in normal healing, there was no or less contraction in the healed skin of mice treated with siCTGF using PSPEI. Histologically, the healed tissues also had distinct papillary structures and dense irregular connective tissues that were lacking in the control scar tissues. This study exemplifies a successful treatment of cutaneous wound healing using a polymer system coupled with RNA interference. Hence, the approach holds a great promise for developing new treatments with novel targets in regenerative medicines.

Aerosol delivery of biocompatible dihydroergotamine-loaded PLGA-PSPE polymeric micelles for efficient lung cancer therapy

Safe and efficient drug delivery systems have received great attention for cancer therapy due to their enhanced cancer-targeting efficiency and reduced undesirable side effects. Administration, safety, and effectiveness are the main issues for clinical trials in nanomedicine. Here, we develop a series of poly(lactic-co-glycolic acid)-co-polyspermine (PLGA-PSPE) copolymers via a simple polymerization reaction between activated carboxyl groups of poly(lactic-co-glycolic acid) (PLGA) and amine groups of polyspermine (PSPE) with different molecular weights (Mw) for safe and efficient lung cancer drug delivery. PLGA-PSPE can self-assemble into polymeric micelles with a low critical micelle concentration. PLGA-PSPE had very low cytotoxicity and hemolytic activity. In addition, PLGA-PSPE also had no potential systemic toxicity after aerosol delivery to mice. Dihydroergotamine tartrate (DHE), which could suppress lung cancer cell survival by induction of apoptosis and mitophagy in the latest study, was employed as the model hydrophobic drug and encapsulated into PLGA-PSPE polymeric micelles (PLGA-PSPE/DHE). PLGA-PSPE/DHE could be stored at 25 °C for 7 days, and showed a controlled and sustained drug release, and time and dose dependent cellular uptake. Moreover, PLGA-PSPE/DHE efficiently increased apoptosis and mitophagy in A549 lung cancer cells. Furthermore, PLGA-PSPE/DHE significantly reduced tumor sizes and numbers, and efficiently suppressed lung tumorigenesis in K-rasLA1 lung cancer model mice after aerosol delivery. These results indicate that PLGA-PSPE polymeric micelles have a potential as an anticancer drug delivery carrier for lung cancer therapy.

Ephedrine-induced mitophagy via oxidative stress in human hepatic stellate cells

The herb Ephedra sinica (also known as Chinese ephedra or Ma Huang), used in traditional Chinese medicine, contains alkaloids identical to ephedrine and pseudoephedrine as its principal active constituents. Recent studies have reported that ephedrine has various side effects in the cardiovascular and nervous systems. In addition, herbal Ephedra, a plant containing many pharmacologically active alkaloids, principally ephedrine, has been reported to cause acute hepatitis. Many studies reported clinical cases, however, the cellular mechanism of liver toxicity by ephedrine remains unknown. In this study, we investigated hepatotoxicity and key regulation of mitophagy in ephedrine-treated LX-2 cells. Ephedrine triggered mitochondrial oxidative stress and depolarization. Mitochondrial swelling and autolysosome were observed in ephedrine-treated cells. Ephedrine also inhibited mitochondrial biogenesis, and the mitochondrial copy number was decreased. Parkin siRNA recovered the ephedrine-induced mitochondrial damage. Excessive mitophagy lead to cell death through imbalance of autophagic flux. Moreover, antioxidants and reducing Parkin level could serve as therapeutic targets for ephedrine-induced hepatotoxicity.

Aerosol delivery of folate-decorated hyperbranched polyspermine complexes to suppress lung tumorigenesis via Akt signaling pathway.

Lung cancer has been a leading cause of cancer mortality worldwide and aerosol-mediated gene therapy endows numerous advantages compared to other traditional modalities. Here, we reported a folic acid (FA)-modified hyperbranched polyspermine (HPSPE) with prominent biocompatibility for lung cancer cell targeted gene therapy. FA was decorated to the HPSPE via an amidation reaction and the physicochemical properties of nanoplexes formed with DNA were characterized. Gel electrophoresis study elucidated that the designed polymer was capable to condense DNA and protect it from degradation by DNase I. Cell viability and transfection efficiency assay in vitro and in vivo indicated its increased transfection performance with lower toxicity. Furthermore, reduced tumor numbers and down-regulation of Akt1 protein after aerosol treatment containing FA-HPSPE/shAkt1 complexes proved its therapeutic potential for lung cancer suppression. Results obtained in this study suggested that FA-HPSPE with highly biocompatibility and targeting capability while forming complexes with shAkt1 and administrated through noninvasive aerosol could be prospective for inhibiting lung tumorigenesis.

The Effects of Gymnema sylvestre in High-Fat Diet-Induced Metabolic Disorders

This study used an integrated approach to investigate the effects of Gymnema sylvestre (GS) extract as a functional dietary supplement with a high-fat diet. This approach examined insulin resistance, the dysfunction of adipose tissue, and liver steatosis. Male C57BL/6J mice were fed a normal chow or high-fat diet (HFD) for the acute and chronic study, in addition to GS in different doses (100, 250 and 500[Formula: see text]mg/kg body weight). Their body composition changes, serum lipid and glucose parameters, adipose and liver tissue histology, and gene expression were measured. It was found that GS significantly suppressed the increase of body weight, serum levels of lipid, insulin and leptin, and adipose tissue, and liver inflammation. GS also demonstrated hypoglycemic effects due to the amylase inhibition activity. Our results support the existence of a relationship between the HFD induced insulin resistance, adipose dysfunction and liver steatosis. In conclusion, GS works as a functional dietary supplement with preventative effects against metabolic disorder.

Population genetic study of 10 short tandem repeat loci from 600 domestic dogs in Korea.

Dogs have long shared close relationships with many humans. Due to the large number of dogs in human populations, they are often involved in crimes. Occasionally, canine biological evidence such as saliva, bloodstains and hairs can be found at crime scenes. Accordingly, canine DNA can be used as forensic evidence. The use of short tandem repeat (STR) loci from biological evidence is valuable for forensic investigations. In Korea, canine STR profiling-related crimes are being successfully analyzed, leading to diverse crimes such as animal cruelty, dog-attacks, murder, robbery, and missing and abandoned dogs being solved. However, the probability of random DNA profile matches cannot be analyzed because of a lack of canine STR data. Therefore, in this study, 10 STR loci were analyzed in 600 dogs in Korea (344 dogs belonging to 30 different purebreds and 256 crossbred dogs) to estimate canine forensic genetic parameters. Among purebred dogs, a separate statistical analysis was conducted for five major subgroups, 97 Maltese, 47 Poodles, 31 Shih Tzus, 32 Yorkshire Terriers, and 25 Pomeranians. Allele frequencies, expected (Hexp) and observed heterozygosity (Hobs), fixation index (F), probability of identity (P(ID)), probability of sibling identity (P(ID)sib) and probability of exclusion (PE) were then calculated. The Hexp values ranged from 0.901 (PEZ12) to 0.634 (FHC2079), while the P(ID)sib values were between 0.481 (FHC2079) and 0.304 (PEZ12) and the P(ID)sib was about 3.35 × 10−5 for the combination of all 10 loci. The results presented herein will strengthen the value of canine DNA to solving dog-related crimes.