Low Plasma Proportion of Omega 3-Polyunsaturated Fatty Acids Predicts Poor Outcome in Acute Non-Cardiogenic Ischemic Stroke Patients / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Alterations in blood fatty acid (FA) composition are associated with cardiovascular diseases. We investigated whether plasma FA composition was related to stroke severity and functional outcome in acute ischemic stroke patients. METHODS: We prospectively enrolled 156 patients with first-episode cerebral infarction, within 7 days of symptom onset. The proportion of FAs was analyzed using gas chromatography, and the summation of the omega-3 polyunsaturated fatty acids (omega3-PUFA), 18:3 omega3 alpha-linolenic acid, 20:3 omega3 eicosatrienoic acid, 20:5 omega3 eicosapentaenoic acid (EPA), and 22:6 omega3 docosahexaenoic acid (DHA) was reported as Sigmaomega3-PUFAs. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score on admission. Poor functional outcome was defined by modified Rankin scale (mRS) > or =3 at three months after the index stroke. RESULTS: Lower proportions of EPA (beta=-0.751), DHA (beta=-0.610), and Sigmaomega3-PUFAs (beta=-0.462) were independently associated with higher NIHSS score, after adjusting for stroke subtype, hemoglobin, high density lipoprotein, high sensitivity C-reactive protein, fasting glucose, 16:0 palmitic acid, and Sigmasaturated fatty acids. Moreover, a lower proportion of DHA (odds ratio [OR]: 0.20, 95% confidence interval [CI]: 0.04-0.88), and Sigmaomega3-PUFAs (OR: 0.22, 95% CI: 0.05-0.84) showed an independent relationship with poor functional outcome after adjusting for age, sex, smoking status, NIHSS score, stroke subtype, and 16:0 palmitic acid. CONCLUSIONS: Our results demonstrate that omega3-PUFAs correlated with stroke severity on admission and functional outcomes at 3 months. omega3-PUFAs are potential blood biomarkers for prognosis of acute non-cardiogenic ischemic stroke patients.

Constitutive Expression of MAP Kinase Phosphatase-1 Confers Multi-drug Resistance in Human Glioblastoma Cells / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Current treatment of glioblastoma after surgery consists of a combination of fractionated radiotherapy and temozolomide. However, it is difficult to completely remove glioblastoma because it has uncertain boundaries with surrounding tissues. Moreover, combination therapy is not always successful because glioblastoma has diverse resistances. To overcome these limitations, we examined the combined effects of chemotherapy and knockdown of mitogen-activated protein kinase phosphatase-1 (MKP-1). MATERIALS AND METHODS: We used ten different anti-cancer drugs (cisplatin, cyclophosphoamide, doxorubicin, epirubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, mitomycin C, and vincristine) to treat glioblastoma multiforme (GBM) cells. Knockdown of MKP-1 was performed using siRNA and lipofectamine. The basal level of MKP-1 in GBM was analyzed based on cDNA microarray data obtained from the Gene Expression Omnibus (GEO) databases. RESULTS: Anti-cancer drug-induced cell death was significantly enhanced by knockdown of MKP-1, and this effect was most prominent in cells treated with irinotecan and etoposide. Treatment with these two drugs led to significantly increased phosphorylation of c-Jun N-terminal kinase (JNK) in a time-dependent manner, while pharmacological inhibition of JNK partially inhibited drug-induced cell death. Knockdown of MKP-1 also enhanced drug-induced phosphorylation of JNK. CONCLUSION: Increased MKP-1 expression levels could be the cause of the high resistance to conventional chemotherapeutics in human GBM. Therefore, MKP-1 is an attractive target for overcoming drug resistance in this highly refractory malignancy.

Proapoptotic Ginsenosides Compound K and Rh2 Enhance Fas-induced Cell Death of Human Astrocytoma Cells Through Distinct Apoptotic Signaling Pathways / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Malignant astrocytomas are among the commonest primary brain tumors and they have a grave prognosis, and so there is an urgent need to develop effective treatment. In this study, we investigated the molecular mechanisms that are responsible for the anti-tumor effect of ginsenosides on human astrocytoma cells. MATERIALS AND METHODS: We tested 13 different ginsenosides for their anti-tumor effect on human malignant astrocytoma cells in conjunction with Fas stimulation. In addition, the cell signaling pathways were explored by using pharmacological inhibitors and performing immunoblot analysis. DCF-DA staining and antioxidant experiments were performed to investigate the role of reactive oxygen species as one of the apoptosis-inducing mechanisms. RESULTS: Among the 13 different ginsenoside metabolites, compound K and Rh2 induced apoptotic cell death of the astrocytoma cells in a caspase- and p38 MAPK-dependent manner, yet the same treatment had no cytotoxic effect on the primary cultured human astrocytes. Combined treatment with ginsenosides and Fas ligand showed a synergistic cytotoxic effect, which was mediated by the reduction of intracellular reactive oxygen species. CONCLUSION: These results suggest that ginsenoside metabolites in combination with Fas ligand may provide a new strategy to treat malignant astrocytomas, which are tumors that are quite resistant to conventional anti-cancer treatment.

Multiplex Analysis of Cytokines in the Serum and Cerebrospinal Fluid of Patients With Alzheimer's Disease by Color-Coded Bead Technology

Background and purpose: The availability and promise of effective treatments for neurodegenerative disorders are increasing the importance of early diagnosis. Having molecular and biochemical markers of Alzheimer's disease (AD) would complement clinical approaches, and further the goals of early and accurate diagnosis. Combining multiple biomarkers in evaluations significantly increases the sensitivity and specificity of the biochemical tests. Methods: In this study, we used color-coded bead-based Luminex technology to test the potential of using chemokines and cytokines as biochemical markers of AD. We measured the levels of 22 chemokines and cytokines in the serum and cerebrospinal fluid (CSF) of 32 de novo patients (13 controls, 11 AD, and 8 Parkinson's disease [PD]). Results: MCP-1 was the only cytokine detectable in CSF, and its levels did not differ between control and disease groups. However, the serum concentration of eotaxin was significantly higher in AD patients than in the control group. Conclusions: The analysis of multiple inflammatory mediators revealed marginal differences in their CSF and serum concentrations for the differential diagnosis of AD and PD. These results provide evidence that immunological responses are not major contributors to the pathogenesis of AD and PD.

Leptin is Associated with Endothelial Dysfunction in Healthy Obese Premenopausal Women

BACKGROUND AND OBJECTIVES: Previous studies have demonstrated that adipokines can have positive and/or negative effects on vascular function. In this study, we attempted to characterize the association of adipokines with endothelium-dependent vasodilation in healthy premenopausal women. SUBJECTS AND METHODS: Noninvasive pulse wave analysis coupled with provocative pharmacological testing with salbutamol was used to measure endothelium-dependent vasodilation in 60 healthy premenopausal women [37 obese women; body mass index (BMI) > or = 25 kg/m2, 23 age-matched non-obese women; BMI<25 kg/m2]. The lipid profile, fasting insulin, glucose, and C-reactive protein (CRP) concentrations in each patient were assessed via standard laboratory techniques, and plasma concentrations of various adipokines, such as adiponectin, leptin, resistin and TNF-alpha, were measured via enzyme immunoassays. RESULTS: In the obese group, higher leptin concentrations were significantly associated with impairments in endothelium-dependent vasodilation (r=-0.371, p=0.005). This association remained significant, even after adjustment for other risk factors (beta=-0.39, p=0.006). However, we determined that there was no significant correlation between endothelium-dependent vasodilation and these variables in the obese group and the control group. CONSLUSION: Increased plasma concentration of leptin was associated with impairment in endothelial function in obese premenopausal women, regardless of the metabolic and inflammatory disturbances associated with obesity.

The Role of the Ubiquitin-Proteasome Pathway in Neurodegenerative Disorders

Impaired function of the Ubiquitin (Ub)/proteasome pathway is one of the molecular mechanisms underlying aging process and neurodegenerative disorders such as Parkinson's Disease and Alzheimer's Disease (AD). Among many vital cellular functions, the Ub/proteasome pathway regulates immune responses via mediating activation of NF-kappa B by pro-inflammatory signals. Dysfunction of this pathway may aberrantly affect the signaling of pro-inflammatory cytokines such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), which are abundantly present in AD brains. To address this, chemokine expression was measured as a readout for IL-1beta and TNF-alpha signaling in human astrocytes. Proteasome inhibitors, MG-132 and lactacystin, suppressed IL-1beta and TNF-alpha-induced expression of MCP-1, RANTES and IP-10, but not that of IL-8. In addition, human astrocytes underwent apoptotic cell death upon treatment with IL-1beta and TNF-alpha only in the presence of the proteasome inhibitors. These results suggest that inhibition of the Ub/proteasome pathway dysregulates pro-inflammatory cytokine signaling in human astrocytes, leading to divergent chemokine expression and enhanced cell death. Therefore, we propose that the immuno-pathologic role of astrocytes in AD brains should be re-evaluated under the circumstances of impaired function of the Ub/proteasome pathway.