Berberine (BBR) is one of the major alkaloids and has been reported to have a variety of pharmacologic effects, including inhibition of cell cycle progression. Here, we investigated the mechanisms of BBR protection of neuronal cells from cell death induced by the Parkinson's disease-related neurotoxin 6-hydroxydopamine (6-OHDA). Pretreatment of SH-SY5Y cells with BBR significantly reduced 6-OHDAinduced generation of reactive oxygen species (ROS), caspase-3 activation, and subsequent cell death. BBR also upregulated heme oxygenase-1 (HO-1) expression, which conferred protection against 6-OHDA-induced dopaminergic neuron injury and besides, effect of BBR on HO-1 was reversed by siRNA-Nrf2. Furthermore, BBR induced PI3K/Akt and p38 activation, which are involved in the induction of Nrf2 expression and neuroprotection. These results suggest that BBR may be useful as a therapeutic agent for the treatment of dopaminergic neuronal diseases.

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The orphan nuclear receptor Nurr1 is primarily expressed in the central nervous system. It has been shown that Nurr1 is necessary for terminal differentiation of dopaminergic (DA) neurons in ventral midbrain. The receptor, however, is also expressed in other organs including bone, even though the role of Nurr1 is not yet understood. Therefore, we investigated the role of Nurr1 in osteoblast differentiation in MC3T3-E1 cells and calvarial osteoblasts derived from Nurr1 null newborn pups. Our results revealed that reduced Nurr1 expression, using Nurr1 siRNA in MC3T3-E1 cells, affected the expression of osteoblast differentiation marker genes, osteocalcin (OCN) and collagen type I alpha 1 (COL1A1), as measured by quantitative real-time PCR. The activity of alkaline phosphatase (ALP), another osteoblast differentiation marker gene, was also decreased in Nurr1 siRNA-treated MC3T3-E1 cells. In addition, Nurr1 overexpression increased OCN and COL1A1 expression. Furthermore, consistent with these results, during osteoblast differentiation, the expression of osteoblast marker genes was decreased in primary cultured mouse calvarial osteoblasts derived from Nurr1 null mice. Collectively, our results suggest that Nurr1 is important for osteoblast differentiation.

Naringin, a flavanone glycoside extracted from various plants, has a wide range of pharmacological effects. In the present study, we investigated naringin’s mechanism of action and its inhibitory effect on lipopolysaccharide-induced tumor necrosis factor-alpha and high-mobility group box 1 expression in macrophages, and on death in a cecal ligation and puncture induced mouse model of sepsis. Naringin increased heme oxygenase 1 expression in peritoneal macrophage cells through the activation of adenosine monophosphate-activated protein kinase, p38, and NF-E2-related factor 2. Inhibition of heme oxygenase 1 abrogated the naringin’s inhibitory effect on high-mobility group box 1 expression and NF-kB activation in lipopolysaccharide-stimulated macrophages. Moreover, mice pretreated with naringin (200 mg/kg) exhibited decreased sepsis-induced mortality and lung injury, and alleviated lung pathological changes. However, the naringin’s protective effects on sepsis-induced lung injury were eliminated by zinc protoporphyrin, a heme oxygenase 1 competitive inhibitor. These results revealed the mechanism underlying naringin’s protective effect in inflammation and may be beneficial for the treatment of sepsis.

Interleukin-18 (IL-18) is a cytokine that enhances innate and adaptive immune responses. Although there are conflicting reports about the roles of IL-18 in melanoma progression, the clinical relevance of IL-18 expression has not been comprehensively studied. In this study, we investigated IL-18 expression and its correlation with patient survival and immune cell infiltration in melanoma using cancer gene expression data publicly available through various databases. IL18 mRNA expression was found to be significantly lower in melanoma tissues than normal tissues. Kaplan–Meier survival analysis showed that IL18 expression was positively correlated with patient survival. To investigate the possible mechanisms by which IL18 expression increased patient survival, we then assessed the correlation between IL18 expression and immune cell infiltration levels. Infiltration of various immune cells, especially CD8+ T and natural killer (NK) cells, which are cytolytic effector cells, was significantly increased by IL18 expression. Additionally, the expression levels of two cytolytic molecules including perforin and granzyme B were significantly positively correlated with IL18 expression. Collectively, this study provides the first evidence that IL18 expression has prognostic value for melanoma patient survival and is strongly correlated with CD8+ T and NK cell infiltration, suggesting the role of IL-18 as a biomarker for predicting melanoma prognosis.

Context.-The ability of intermediate trophoblasts to invade maternal tissue during placentation depends on how well they can degrade the extracellular matrix. Invasion into the extracellular matrix requires many complex proteases. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) is a novel family of secreted metalloproteinases. The ADAMTS-1, -4, -5, and -14 subtypes are known to be expressed in human placenta, but little is understood about their expression patterns.Objective.-To examine the expression patterns of ADAMTS-1, -4, -5, and -14 in specific human placenta cell types during gestation and in gestational trophoblastic diseases.Design.-Placental tissues were obtained from 25 pregnant women and 21 cases of gestational trophoblastic diseases (10 early complete moles, 3 placental site trophoblastic tumors, 4 invasive moles, and 4 choriocarcinomas). The expression of the 4 ADAMTS was analyzed by immunohistochemistry.Results.-ADAMTS-1, -4, -5, and -14 were differentially expressed by the human placenta throughout gestation in a time-specific and cell type-specific manner, as well as in gestational trophoblastic diseases. ADAMTS-1 showed gradually strong staining intensity in gestational trophoblastic diseases according to the invasive potential but showed consistent strong intensity throughout normal placenta. ADAMTS-4 and ADAMTS-5 exhibited higher and restricted expression in first-trimester intermediate trophoblasts. They also exhibited comparably strong expression in gestational trophoblastic diseases. However, ADAMTS-14 expression remained unchanged throughout gestation.Conclusions.-The restricted expression pattern of ADAMTS-4 and ADAMTS-5 and their increased expression in gestational trophoblastic diseases suggest that these 2 ADAMTS subtypes are associated with a biological phenotype of trophoblasts involved in human placentation and the development of gestational trophoblastic diseases.

Nurr1 is an orphan nuclear transcription factor essential for the terminal differentiation of dopamine (DA) neurons in the ventral midbrain (VM). To identify the Nurr1-target genes, we carried out microarray and quantitative real-time PCR analyses of Nurr1 null and wild-type mice in VM at embryonic day (E) 12.5 and shortly after birth (P0). In addition to the absence of mRNAs of DA synthesizing enzymes, the guanosine 5¢-triphosphate (GTP) cyclohydrolase I (GTPCH) was also substantially reduced in the VM of Nurr1-null mice. GTPCH is the first enzyme in the synthesis pathway of tetrahydrobiopterin (BH4), an essential cofactor for tyrosine hydroxylase in DA synthesis. In the mouse, Nurr1 and GTPCH mRNA were first detected at E10.5, and GTPCH transcription paralleled that of Nurr1. Small interfering RNA targeted against Nurr1 decreases GTPCH expression in MC3T3-E1 osteoblasts in cell culture. Cotransfection of Nurr1 and the GTPCHluciferase (luc) reporter increased the luc activity by about threefold in N2A cells. Additional analysis using 5¢-deletions and mutants revealed that Nurr1 activates GTPCH transcription indirectly through the proximal promoter region, in the absence of the nerve growth factor-induced clone B (NGFI-B) responsive element-like sites, similarly, as recently reported for DA transporter regulation by Nurr1.

Tussilagone, extracted from Tussilago farfara is an oriental medicine used for asthma and bronchitis. We investigated its mechanism of action, its inhibitory effects on lipopolysaccharide-induced inflammation in macrophages, and its impact on viability in a cecal ligation and puncture (CLP)-induced mouse model of sepsis. Tussilagone suppressed the expression of the inflammatory mediators, nitric oxide and prostaglandin E2, and the inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and high-mobility group box 1 (HMGB1), in lipopolysaccharide-stimulated RAW 264.7 cells and peritoneal macrophages. Tussilagone also reduced the activation of the mitogen-activated protein kinases and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) involved in the activation of various inflammatory mediators in activated macrophages. Moreover, tussilagone administration (1 mg/kg and 10 mg/kg) produced decreased mortality and lung injury in CLP-activated septic mice. Augmented expression of cyclooxygenase (COX)-2 and TNF-α in pulmonary alveolar macrophages of septic mice were attenuated by tussilagone administration. Tussilagone also suppressed the induction of nitric oxide, prostaglandin E2, TNF-α and HMGB1 in the serum of the septic mice. Overall, tussilagone exhibited protective effects against inflammation and polymicrobial sepsis by suppressing inflammatory mediators possibly via the inhibition of NF-κB activation and the MAP kinase pathway. These results suggest the possible use of tussilagone for developing novel therapeutic modalities for sepsis and other inflammatory diseases.