The American journal of Chinese medicine
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Centella asiatica (L.) Urb. (C. asiatica) has been widely treated for inflammation-related diseases in China for thousands of years. While C. asiatica showed relevant effects as traditional medicine, the mechanism of C. asiatica suppressing inflammation has not been thoroughly investigated. Therefore, this study was conducted to reveal the anti-inflammatory mechanism of methanol fraction from C. asiatica (MCA) at the molecular level in murine macrophages. ⋯ TXY motif phosphorylation in the activation loops of mitogen-activated protein kinases (MAPKs) was also suppressed by MCA treatment. Further investigation revealed that MCA inhibited transforming growth factor-[Formula: see text]-activated kinase 1 (TAK1) phosphorylation and IL-1 receptor-associated kinase (IRAK1) degradation, the upstream kinases activating nuclear factor [Formula: see text]B and MAPKs. Taken together, MCA exhibited anti-inflammatory properties via the downregulation of IRAK1-TAK1 signaling pathways.
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Hepatic ischemia-reperfusion (IR) injury remains the major cause of liver damage post-liver surgery or transplantation. Diminishing oxidative stress and inflammatory responses is a powerful channel to reduce the rate of morbidity and mortality. Gastrodin (GSTD), a bioactive compound extracted from the traditional Chinese herbal agent with a long history of clinical application in nervous system diseases, is suggested to possess anti-oxidative effects on liver diseases, such as nonalcoholic fatty liver disease. ⋯ Meanwhile, we observed a great induction of heme oxygenase-1 (HO-1) and an activation of the p38 mitogen-activated protein kinases/nuclear factor erythroid 2-related factor 2 (p38MAPK/Nrf2) pathway in response to the GSTD pretreatment, while the protective effects upon GSTD diminished in mice with HO-1 heterozygous mutation. In addition, GSTD inhibited IR induced toll-like receptor (TLR) 4, but not TLR2 in a HO-1 dependent manner, leading to a down-regulation of cytokines, such as interleukin (IL)-6 and TNF-[Formula: see text]. Collectively, our findings revealed GSTD attenuated liver IR injury via activation of the HO-1 pathway, providing a novel therapeutic strategy to minimize the IR induced oxidative stress in the process of liver transplantation.
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Corosolic acid (CA) is the main active component of Lagetstroemia speciosa and has been known to serve as several different pharmacological effects, such as antidiabetic, anti-oxidant, and anticancer effects. In this study, effects of CA on the hepatic lipid accumulation were examined using HepG2 cells and tyloxapol (TY)-induced hyperlipidemia ICR mice. CA significantly inhibited hepatic lipid accumulation via inhibition of SREBPs, and its target genes FAS, SCD1, and HMGCR transcription in HepG2 cells. ⋯ In addition, CA clearly alleviated serum ALT, AST, TG, TC, low-density lipoprotein cholesterol (LDL-C), and increased high-density lipoprotein cholesterol (HDL-C) levels, and obviously attenuated TY-induced liver steatosis and inflammation. Moreover, CA significantly upregulated AMPK, ACC, LKB1 phosphorylation, and significantly inhibited lipin1, SREBPs, TNF- α , F4/80, caspase-1 expression, NF- κ B translocation, and MAPK activation in TY-induced hyperlipidemia mice. Our results suggest that CA is a potent antihyperlipidemia and antihepatic steatosis agent and the mechanism involved both lipogenesis and cholesterol synthesis and inflammation response inhibition via AMPK/SREBPs and NF- κ B/MAPK signaling pathways.
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The medicinal plant Rhodiola crenulata grows at high altitudes in the Arctic and mountainous regions and is commonly used in phytotherapy in Eastern European and Asian countries. In the present study, we investigated the anti-apoptotic effect of Rhodiola crenulata and its neuroprotective mechanism of action in a rat model of D-galactose-induced aging. Two groups of twelve-week-old male Wistar rats received a daily injection of D-galactose (150 mg/kg/day, i.p.) and orally administered Rhodiola crenulata (0, 248 mg/kg/day) for eight weeks, while a control group received a saline injection (1 ml/kg/day, i.p.). ⋯ In addition, D-galactose impaired the phosphorylation of PI3K/Akt, an important survival signaling event in neurons. Rhodiola crenulata, however, protected against all these neurotoxicities in aging brains. The present study suggests that neuronal survival promoted by Rhodiola crenulata may be a potentially effective method to enhance the resistance of neurons to age-related disorders.
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Inadequate responses to traditional chemotherapeutic agents in cholangiocarcinoma (CCA) emphasize a requirement for new effective compounds for the treatment of this malignancy. This study aimed to investigate the antiproliferative property of cucurbitacin B on KKU-100 CCA cells. The determination of underlying molecular mechanisms was also carried out. ⋯ Finally, the effect of cucurbitacin B on upstream receptor tyrosine kinases regulating FAK activation was elucidated. The results showed that the inhibitory effect of cucurbitacin B on FAK activation in CCA cells is mediated via interference of EGFR and HER2 expression. Collectively, cucurbitacin B might be a promising drug for CCA treatment by targeting FAK protein.