Eun Jeong Sohn

Transduced PEP-1-FK506BP Ameliorates Atopic Dermatitis in NC/Nga Mice

Immunophilin, FK506-binding protein 12 (FK506BP), is a receptor protein for the immunosuppressive drug FK506 by the FK506BP/FK506 complex. However, the precise function of FK506BP in inflammatory diseases remains unclear. Therefore, we examined the protective effects of FK506BP on atopic dermatitis (AD) in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced HaCaT cells and 2,4-dinitrofluorobenzene-induced AD-like dermatitis in Nishiki-nezumi Cinnamon/Nagoya (NC/Nga) mice using a cell-permeable PEP-1-FK506BP. Transduced PEP-1-FK506BP significantly inhibited the expression of cytokines, as well as the activation of NF-κB and mitogen-activated protein kinase (MAPK) in TNF-α/IFN-γ-induced HaCaT cells. Furthermore, topical application of PEP-1-FK506BP to NC/Nga mice markedly inhibited AD-like dermatitis as determined by a histological examination and assessment of serum IgE levels, as well as cytokines and chemokines. These results indicate that PEP-1-FK506BP inhibits NF-κB and MAPK activation in cells and AD-like skin lesions by reducing the expression levels of cytokines and chemokines, thus suggesting that PEP-1-FK506BP may be a potential therapeutic agent for AD.

Transduced human PEP-1-catalase fusion protein attenuates ischemic neuronal damage.

Antioxidant enzymes are considered to have beneficial effects against various diseases mediated by reactive oxygen species (ROS). Ischemia is characterized by both oxidative stress and changes in the antioxidant defense system. Catalase (CAT) and superoxide dismutase (SOD) are major antioxidant enzymes by which cells counteract the deleterious effects of ROS. To investigate the protective effects of CAT, we constructed PEP-1-CAT cell-permeative expression vectors. When PEP-1-CAT fusion proteins were added to the culture medium of neuronal cells, they rapidly entered the cells and protected them against oxidative stress-induced neuronal cell death. Immunohistochemical analysis revealed that PEP-1-CAT prevented neuronal cell death in the hippocampus induced by transient forebrain ischemia. Moreover, we showed that the protective effect of PEP-1-CAT was observed in neuronal cells treated with PEP-1-SOD. Therefore, we suggest that transduced PEP-1-CAT and PEP-1-SOD fusion proteins could be useful as therapeutic agents for various human diseases related to oxidative stress, including stroke.

Transduced Tat-SAG fusion protein protects against oxidative stress and brain ischemic insult.

Reactive oxygen species (ROS) have been implicated in the pathogenesis of ischemic brain injury. Sensitive to apoptosis gene (SAG) is a RING-finger protein that exhibits antioxidant activity against a variety of redox reagents. However, the protective effect of SAG in brain ischemic injury is unclear. Here, we investigated the protective effects of a Tat-SAG fusion protein against cell death and ischemic insult. When Tat-SAG fusion protein was added to the culture medium of astrocytes, it rapidly entered the cells and protected them against oxidative stress-induced cell death. Immunohistochemical analysis revealed that, when Tat-SAG fusion protein was intraperitoneally injected into gerbils, wild-type Tat-SAG prevented neuronal cell death in the CA1 region of the hippocampus in response to transient forebrain ischemia. In addition, wild-type Tat-SAG fusion protein decreased lipid peroxidation in the brain compared with mutant Tat-SAG- or vehicle-treated animals. Our results demonstrate that Tat-SAG fusion protein is a tool for the treatment of ischemic insult and it can be used in protein therapy for various disorders related to ROS, including stroke.

Protective effects of PEP-1-Catalase on stress-induced cellular toxicity and MPTP-induced Parkinson's disease.

Parkinson’s disease (PD) is a neurodegenerative disability caused by a decrease of dopaminergic neurons in the substantia nigra (SN). Although the etiology of PD is not clear, oxidative stress is believed to lead to PD. Catalase is antioxidant enzyme which plays an active role in cells as a reactive oxygen species (ROS) scavenger. Thus, we investigated whether PEP-1-Catalase protects against 1-methyl-4-phenylpyridinium (MPP+) induced SH-SY5Y neuronal cell death and in a 1-methyl-4-phenyl-1,2,3,6-trtrahydropyridine (MPTP) induced PD animal model. PEP-1-Catalase transduced into SH-SY5Y cells significantly protecting them against MPP+-induced death by decreasing ROS and regulating cellular survival signals including Akt, Bax, Bcl-2, and p38. Immunohistochemical analysis showed that transduced PEP-1-Catalase markedly protected against neuronal cell death in the SN in the PD animal model. Our results indicate that PEP-1-Catalase may have potential as a therapeutic agent for PD and other oxidative stress related diseases. [BMB Reports 2015; 48(7): 395-400]

PEP-1–metallothionein-III protein ameliorates the oxidative stress-induced neuronal cell death and brain ischemic insults

BACKGROUND Oxidative stress is considered to be involved in a number of human diseases including ischemia. Metallothioneins (MT)-III can protect neuronal cells from the cytotoxicity of reactive oxygen species (ROS). However, MT-III proteins biological function is unclear in ischemia. Thus, we examined the protective effects of MT-III proteins on oxidative stress-induced neuronal cell death and brain ischemic insult. METHODS A human MT-III gene was fused with a protein transduction domain, PEP-1 peptide, to construct a cell permeable PEP-1-MT-III protein. PEP-1-MT-III protein was purified using affinity chromatograph. Transduced PEP-1-MT-III proteins were detected by Western blotting and immunoflourescence. Cell viability and DNA fragmentation were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-dipheyltetrazolium bromide (MTT) assay and terminal dexoynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining, respectively. Brain ischemic injury was detected with immunohistochemistry. RESULTS Purified PEP-1-MT-III proteins transduced into astrocytes in a time- and dose-dependent manner and protected against oxidative stress-induced cell death. Also, transduced PEP-1-MT-III proteins efficiently protected cells against DNA fragmentation. Furthermore, immunohistochemical analysis revealed that PEP-1-MT-III prevented neuronal cell death in the CA1 region of the hippocampus induced by transient forebrain ischemia. We demonstrated that transduced PEP-1-MT-III protein protects against oxidative stress induced cell death in vitro and in vivo. GENERAL SIGNIFICANCE Transduced PEP-1-MT-III protein has neuroprotective roles as an antioxidant in vitro and in vivo. PEP-1-MT-III protein is a potential therapeutic agent for various human brain diseases such as stroke, Alzheimers disease, and Parkinsons disease.

PEP-1-PON1 Protein Regulates Inflammatory Response in Raw 264.7 Macrophages and Ameliorates Inflammation in a TPA-Induced Animal Model

Paraoxonase 1 (PON1) is an antioxidant enzyme which plays a central role in various diseases. However, the mechanism and function of PON1 protein in inflammation are poorly understood. Since PON1 protein alone cannot be delivered into cells, we generated a cell permeable PEP-1-PON1 protein using protein transduction domains, and examined whether it can protect against cell death in lipopolysaccharide (LPS) or hydrogen peroxide (H2O2)-treated Raw 264.7 cells as well as mice with 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced skin inflammation. We demonstrated that PEP-1-PON1 protein transduced into Raw 264.7 cells and markedly protected against LPS or H2O2-induced cell death by inhibiting cellular reactive oxygen species (ROS) levels, the inflammatory mediator’s expression, activation of mitogen-activated protein kinases (MAPKs) and cellular apoptosis. Furthermore, topically applied PEP-1-PON1 protein ameliorates TPA-treated mice skin inflammation via a reduction of inflammatory response. Our results indicate that PEP-1-PON1 protein plays a key role in inflammation and oxidative stress in vitro and in vivo. Therefore, we suggest that PEP-1-PON1 protein may provide a potential protein therapy against oxidative stress and inflammation.

Transduced PEP-1-FK506BP inhibits the inflammatory response in the Raw 264.7 cell and mouse models

FK506 binding protein 12 (FK506BP) is an immunophilin that acts as a receptor for the immunosuppressant drug FK506. Although the precise action of FK506BP remains unclear, it has emerged as a potential drug target for several inflammatory diseases. This study investigated the protective effects of FK506BP on inflammation in vitro and in vivo using protein transduction. A cell-permeable expression vector PEP-1-FK506BP was constructed. Lipopolysaccharide (LPS)- or 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated Raw 264.7 cells and ICR mice were treated with PEP-1-FK506BP. The expression of inflammatory response enzymes and cytokines was analyzed by Western blot, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and electrophoretic mobility shift assay. PEP-1-FK506BP efficiently transduced into Raw 264.7 cells and markedly inhibited the expression levels of cyclooxygenase-2 as well as pro-inflammatory cytokines. Furthermore, transduced PEP-1-FK506BP significantly reduced activation of nuclear factor-kappa B (NF-κB) and phosphorylation of p38 mitogen-activated protein kinase (MAPK) in the cells, whereas PEP-1-FK506BP reduced phosphorylation of p38 and extracellular signal-regulated kinase (ERK) in the animal models. These results indicate that PEP-1-FK506BP inhibits inflammatory response cytokines and enzymes by blocking NF-κB and MAPK including the phosphorylation of p38 and/or ERK MAPK in vitro and in vivo, suggesting that PEP-1-FK506BP may be a therapeutic agent against inflammatory skin diseases.

Anti-inflammatory effect of transduced PEP-1-heme oxygenase-1 in Raw 264.7 cells and a mouse edema model

Heme oxygenase-1 (HO-1), which catalyzes the degradation of free heme to biliverdin, carbon monoxide (CO), and free iron (Fe(2+)), is up-regulated by several cellular stress and cell injuries, including inflammation, ischemia and hypoxia. In this study, we examined whether fusion of HO-1 with PEP-1, a protein transduction domain that is able to deliver exogenous molecules to living cells or tissues, would facilitate HO-1 delivery to target cells and tissues, and thereby effectively exert a therapeutically useful response against inflammation. Western blot analysis demonstrated that PEP-1-HO-1 fusion proteins were transduced into Raw 264.7 cells in time- and dose-dependent manners, and were stably maintained in the cells for about 60h. In addition, fluorescence analysis revealed that only PEP-1-HO-1 fusion proteins were significantly transduced into the cytoplasm of cells, while HO-1 proteins failed to be transduced. In lipopolysaccharide (LPS)-stimulated Raw 264.7 cells and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse edema model, transduced PEP-1-HO-1 fusion proteins effectively inhibited the overexpression of pro-inflammatory mediators and cytokines. Also, histological analysis demonstrated that PEP-1-HO-1 remarkably suppressed ear edema. The results suggest that the PEP-1-HO-1 fusion protein can be used as a therapeutic molecule against reactive oxygen species-related inflammatory diseases.

PEP-1-heat shock protein 27 protects from neuronal damage in cells and in a Parkinson's disease mouse model.

Heat shock proteins (HSPs) are a highly conserved family of proteins that are induced in response to various environmental stressors including reactive oxygen species. HSP27 is a chaperone protein with the ability to increase cell survival in response to oxidative stress. Parkinson’s disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons. Although the mechanism of PD remains unclear, oxidative stress is known to be important in its pathogenesis. This study investigated the protective effects of PEP‐1‐HSP27 on neuronal damage induced by 1‐methyl‐4‐phenyl pyridinium (MPP+) in SH‐SY5Y cells and in a 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐induced PD mouse model. PEP‐1‐HSP27 rapidly entered the cells and protected them against MPP+‐induced toxicity by inhibiting the reactive oxygen species levels and DNA fragmentation. Furthermore, transduced PEP‐1‐HSP27 prevented dopaminergic neuronal cell death in the substantia nigra of MPTP‐induced PD mouse models. These results demonstrate that PEP‐1‐HSP27 provides a potential strategy for therapeutic delivery against various diseases and is a potential tool for the treatment of PD.

PEP-1-FK506BP inhibits alkali burn-induced corneal inflammation on the rat model of corneal alkali injury.

FK506 binding protein 12 (FK506BP) is a small peptide with a single FK506BP domain that is involved in suppression of immune response and reactive oxygen species. FK506BP has emerged as a potential drug target for several inflammatory diseases. Here, we examined the protective effects of directly applied cell permeable FK506BP (PEP-1-FK506BP) on corneal alkali burn injury (CAI). In the cornea, there was a significant decrease in the number of cells expressing pro-inflammation, apoptotic, and angiogenic factors such as TNF-α, COX-2, and VEGF. Both corneal opacity and corneal neovascularization (CNV) were significantly decreased in the PEP-1-FK506BP treated group. Our results showed that PEP-1-FK506BP can significantly inhibit alkali burn-induced corneal inflammation in rats, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors and inflammatory cytokines. These results suggest that PEP-1-FK506BP may be a potential therapeutic agent for CAI. [BMB Reports 2015; 48(11): 618-623]