PEP-1-PEA-15 protects against toxin-induced neuronal damage in a mouse model of Parkinson's disease

Background

PEA-15 is abundantly expressed in both neurons and astrocytes throughout the brain. It is a multifunctional protein with the ability to increase cell survival via anti-apoptotic and anti-proliferative properties. However, the function of PEA-15 in neuronal diseases such as Parkinson's disease (PD) remains unclear. In this study, we investigated the protective effects of PEA-15 on neuronal damage induced by MPP⁺ in neuroblastoma SH-SY5Y and BV2 microglia cells and in a MPTP-induced PD mouse model using cell-permeable PEP-1-PEA-15.

Methods

PEP-1-PEA-15 was purified using affinity chromatography. Cell viability and DNA fragmentation were examined by MTT assay and TUNEL staining. Dopaminergic neuronal cell death in the animal model was examined by immunohistochemistry.

Results

PEP-1-PEA-15 transduced into the SH-SY5Y and BV2 cells in a time- and dose-dependent manner. Transduced PEP-1-PEA-15 protected against MPP⁺-induced toxicity by inhibiting intracellular ROS levels and DNA fragmentation. Further, it enhanced the expression levels of Bcl-2 and caspase-3 while reducing the expression levels of Bax and cleaved caspase-3. We found that PEP-1-PEA-15 transduced into the substantia nigra and prevented dopaminergic neuronal cell death in a MPTP-induced PD mouse. Also, we showed the neuroprotective effects in the model by demonstrating that treatment with PEP-1-PEA-15 ameliorated MPTP-induced behavioral dysfunctions and increased dopamine levels in the striatum.

Conclusions

PEP-1-PEA-15 can efficiently transduce into cells and protects against neurotoxin-induced neuronal cell death in vitro and in vivo.

General significance

These results demonstrate the potential for PEP-1-PEA-15 to provide a new strategy for protein therapy treatment of a variety of neurodegenerative diseases including PD.     

Morphological observations of Echinochasmus japonicus cercariae and the in vitro maintenance of its life cycle from cercariae to adults

The cercaria morphology of Echinochasmus japonicus was investigated using light and scanning electron microscopy. Cercariae, liberated from naturally infected snails (Parafossarulus manchouricus), had ovoid bodies and diminutive tails. The cercaria tegument was covered with minute spines. Four type II sensory papillae were observed on the dorsal side of the oral sucker, and type I papillae were distributed on the dorsal tegument surfaces. When cercariae were kept in the same bath as the freshwater fish, Pseudorasbora parva, which were free from trematode infections, parasites encysted only in the gills of fishes at day 4 postinfection (PI). The outermost metacercaria wall was fully formed in host tissues at day 7 PI. Adult worms were recovered from the intestines of rats, chicks, and ducks 28 days after experimental exposure to metacercariae. The head crown of the adult was armed with 24 collar spines, which were interrupted dorsal to the oral sucker, and the species was identified as E. japonicus.     

Glu–Phe from onion (Allium Cepa L.) attenuates lipogenesis in hepatocytes

A Glu–Phe (EF) was isolated from onion (Allium cepa L. cv. Sunpower). The chemical structure of EF was determined by nuclear magnetic resonance and electrospray ionization–mass (ESI?MS) spectroscopy. We showed that EF reduced lipid accumulation in mouse hepatocytes by inhibiting the expression of sterol regulatory element-binding protein-1c (SREBP–1c) and its lipogenic target genes. We also found that AMP-activated protein kinase (AMPK) was required for the inhibitory effect of EF on lipid accumulation in mouse hepatocytes. Furthermore, EF was qualified in nine onion cultivars by selective multiple reaction-monitoring detection of liquid chromatography–ESI?MS. These results suggest that EF could contribute to the beneficial effect of onion supplement in maintaining hepatic lipid homeostasis.     

Role of Hck in the pathogenesis of encephalomyocarditis virus-induced diabetes in mice

Soluble mediators such as interleukin-1beta, tumor necrosis factor alpha (TNF-alpha), and inducible nitric oxide synthase (iNOS) produced from activated macrophages play an important role in the destruction of pancreatic beta cells in mice infected with a low dose of the D variant of encephalomyocarditis (EMC-D) virus. The tyrosine kinase signaling pathway was shown to be involved in EMC-D virus-induced activation of macrophages. This investigation was initiated to determine whether the Src family of kinases plays a role in the activation of macrophages, subsequently resulting in the destruction of beta cells, in mice infected with a low dose of EMC-D virus. We examined the activation of p59/p56(Hck), p55(Fgr), and p56/p53(Lyn) in macrophages from DBA/2 mice infected with the virus. We found that p59/p56(Hck) showed a marked increase in both autophosphorylation and kinase activity at 48 h after infection, whereas p55(Fgr) and p56/p53(Lyn) did not. The p59/p56(Hck) activity was closely correlated with the tyrosine phosphorylation level of Vav. Treatment of EMC-D virus-infected mice with the Src kinase inhibitor, PP2, resulted in the inhibition of p59/p56(Hck) activity and almost complete inhibition of the production of TNF-alpha and iNOS in macrophages and the subsequent prevention of diabetes in mice. On the basis of these observations, we conclude that the Src kinase, p59/p56(Hck), plays an important role in the activation of macrophages and the subsequent production of TNF-alpha and nitric oxide, leading to the destruction of pancreatic beta cells, which results in the development of diabetes in mice infected with a low dose of EMC-D virus.     

Echinostoma ilocanum infection in Oddar Meanchey Province, Cambodia

Fecal examinations using the Kato Katz technique were performed on a total of 1,287 villagers (945 students and 342 general inhabitants) of Oddar Meanchey Province, Cambodia in May 2007 and November 2009. The overall intestinal helminth egg positive rate was 23.9%, and the most prevalent helminth species was hookworms (21.6%). Other helminth eggs detected included echinostomes (1.0%), Enterobius vermicularis (0.8%), small trematode eggs (0.7%), which may include Opisthorchis viverrini and Haplorchis spp., and Hymenolepis nana (0.4%). In order to recover adult echinostomes, we treated 2 patients with 10-15 mg/kg praziquantel and purged. Total 14 adult echinostomes, 1 and 13 worms from each patient, were collected. The echinostomes characteristically had 49-51 collar spines and 2 round or slightly lobated testes. They were identified as Echinostoma ilocanum (Garrison, 1908) Odhner, 1911. So far as literature are concerned, this is the first record on the discovery of human E. ilocanum infection in Cambodia.     

Four Cases of Taenia saginata Infection with an Analysis of COX1 Gene

Human taeniases had been not uncommon in the Republic of Korea (=Korea) until the 1980s. The prevalence decreased and a national survey in 2004 revealed no Taenia egg positive cases. However, a subsequent national survey in 2012 showed 0.04% (10 cases) prevalence of Taenia spp. eggs suggesting its resurgence in Korea. We recently encountered 4 cases of Taenia saginata infection who had symptoms of taeniasis that included discharge of proglottids. We obtained several proglottids from each case. Because the morphological features of T. saginata are almost indistinguishable from those of Taenia asiatica, molecular analyses using the PCR-RFLP and DNA sequencing of the cytochrome c oxidase subunit 1 (cox1) were performed to identify the species. The PCR-RFLP patterns of all of the 4 specimens were consistent with T. saginata, and the cox1 gene sequence showed 99.8-100% identity with that of T. saginata reported previously from Korea, Japan, China, and Cambodia. All of the 4 patients had the history of travel abroad but its relation with contracting taeniasis was unclear. Our findings may suggest resurgence of T. saginata infection among people in Korea.     

Survival Nomogram for Curatively Resected Korean Gastric Cancer Patients: Multicenter Retrospective Analysis with External Validation

BackgroundA small number of nomograms have been previously developed to predict the individual survival of patients who undergo curative resection for gastric cancer. However, all were derived from single high-volume centers. The aim of this study was to develop and validate a nomogram for gastric cancer patients using a multicenter database.MethodsWe reviewed the clinicopathological and survival data of 2012 patients who underwent curative resection for gastric cancer between 2001 and 2006 at eight centers. Among these centers, six institutions were randomly assigned to the development set, and the other two centers were assigned to the validation set. Multivariate analysis using the Cox proportional hazard regression model was performed, and discrimination and calibration were evaluated by external validation.ResultsMultivariate analyses revealed that age, tumor size, lymphovascular invasion, depth of invasion, and metastatic lymph nodes were significant prognostic factors for overall survival. In the external validation, the concordance index was 0.831 (95% confidence interval, 0.784–0.878), and Hosmer-Lemeshow chi-square statistic was 3.92 (P = 0.917).ConclusionsWe developed and validated a nomogram to predict 5-year overall survival after curative resection for gastric cancer based on a multicenter database. This nomogram can be broadly applied even in general hospitals and is useful for counseling patients, and scheduling follow-up.