Building Flexible Escherichia coli Modules for Bifunctionalizing n-Octanol: The Byproduct of Oleic Acid Biorefinery.

Artificial biorefinery of oleic acid into 1,10-decanedioic acid represents a revolutionizing route to the sustainable production of chemically difficult-to-make bifunctional chemicals. However, the carbon atom economy is extremely low (56%) due to the formation of unifunctional n-octanol. Here, we report a panel of recombinant Escherichia coli modules for diverse bifunctionalization, where the desired genetic parts are well distributed into different modules that can be flexibly combined in a plug-and-play manner. The designed ω-functionalizing modules could achieve ω-hydroxylation, consecutive ω-oxidation, or ω-amination of n-octanoic acid. By integrating these advanced modules with the reported oleic acid-cleaving modules, high-value C8 and C10 products, including ω-hydroxy acid, ω-amino acid, and α,ω-dicarboxylic acid, were produced with 100% carbon atom economy. These ω-functionalizing modules enabled the complete use of all of the carbon atoms from oleic acid (released from plant oil) for the green synthesis of structurally diverse bifunctional chemicals.

Li-Dan-He-Ji Improves Infantile Cholestasis Hepatopathy Through Inhibiting Calcium-Sensing Receptor-Mediated Hepatocyte Apoptosis.

Infantile cholestatic hepatopathy (ICH) is a clinical syndrome characterized by the accumulation of cytotoxic bile acids in infancy, leading to serious liver cirrhosis or liver failure. The aetiology of ICH is complicated and some of them is unknown. Regardless of the aetiology, the finial pathology of ICH is hepatocyte apoptosis caused by severe and persistent cholestasis. It is already known that activation of calcium-sensing receptor (CaSR) could lead to the apoptosis of cardiomyocytes. However, the mechanism by CaSR-mediated cholestasis-related hepatocyte apoptosis is not fully understood. Li-Dan-He-Ji (LDHJ), a Traditional Chinese Medicine prescription, was developed to treat ICH. Another aim of this study was to investigate the possible mechanisms of LDHJ in cholestasis-related hepatocyte apoptosis. Using the primary hepatocytes, we first investigated the molecular mechanism of CaSR-mediated hepatocyte apoptosis in cholestasis. Then we prepared LDHJ granules and used ultra-high-performance liquid chromatography to identify the predominant drugs; confirmed the stability of the main substances; and for cell experiments screened forsythoside-A, emodin and chlorogenic acid as the three active substances of LDHJ granules. In the young rats with ANIT-induced intrahepatic cholestasis and the primary hepatocytes with TCDC-induced cholestasis-related hepatocyte apoptosis, the levels of liver injury and cholestasis-related biomarkers, calcium-sensing receptor (CaSR), hepatocyte apoptosis, Bax/Bcl-2 ratio, Cytochrome-C, caspase-3, phosphorylated-c-Jun NH2-terminal kinase (p-JNK)/JNK, and p-P38/P38 were all increased, while the levels of p-extracellular signal-regulated kinase (p-ERK)/ERK were decreased. However, LDHJ granules and its three active substances effectively reversed these changes. Furthermore, the three active substances reduced the increases in the intracellular calcium concentration ([Ca2+]i) and ROS levels and attenuated the dissipation of the mitochondria membrane potential in the TCDC-induced primary hepatocytes. The opposite results were obtained from the TCDC-induced primary hepatocytes treated with an agonist of CaSR (GdCl3) plus forsythoside-A, emodin or chlorogenic acid. Based on the results from in vivo and in vitro studies, LDHJ functions as an antagonist of CaSR to regulate hepatocyte apoptosis in cholestasis through the mitochondrial pathway and mitogen-activated protein kinase pathway.

Bufalin reverses ABCB1-mediated drug resistance in colorectal cancer.

Multidrug resistance (MDR), mainly mediated by ABCB1 transporter, is a major cause for chemotherapy failure. Bufalin (BU), an active component of the traditional Chinese medicine chan'su, has been reported to have antitumor effects on various types of cancer cells. The purpose of this present study was to investigate the reversal effect of BU on ABCB1-mediated multidrug resistance in colorectal cancer. BU at safe concentration (5, 10, 20 nM) could reverse chemosensitivity of ABCB1-overexpression HCT8/ADR, LoVo/ADR and HCT8/ABCB1 nearly back to their parental cells level. In addition, results from the drug accumulation studies revealed that BU was able to enhance intracellular accumulation of doxorubicin (DOX) and Rhodamine 123 (Rho-123) in a dose-dependent manner. Furthermore, Western blot assays showed that BU significantly inhibited the expression level of ABCB1 protein. Meanwhile, BU stimulated the ATPase activity of ABCB1, which suggested that BU might be a substrate of ABCB1. More interestingly, docking analysis predicted that BU could be docked into the large hydrophobic drug-binding cavity of human ABCB1. Importantly, BU remarkable increased the effect of DOX against the ABCB1 resistant HCT8/ADR colorectal cell xenografts in nude mice, without inducing any obvious toxicity. Overall, we concluded that BU efficiently reversed ABCB1-mediated MDR through not only inhibited the efflux function of ABCB1, but also down-regulate its protein expression, which might represent a potential and superior ABCB1 modulator in colorectal cancer.

Synergistic Effect of Zuo Jin Wan on DDP-Induced Apoptosis in Human Gastric Cancer SGC-7901/DDP Cells.

A traditional Chinese medicine (TCM) formula, Zuo Jin Wan (ZJW), has been found as an anticancer drug in human cancer. In this study, we investigated the synergistic effect of ZJW extracts on DDP-induced apoptosis in human gastric cancer SGC-7901/DDP cells. Our results demonstrated that ZJW extracts could increase the sensitivity of SGC-7901/DDP cells to DDP by increasing the concentration of DDP in cytoplasm and enhance the proapoptosis of DDP by upregulating the JNK and Bax expression, downregulating the Bcl-2 expression, increasing the accumulation of Cytochrome C in cytoplasm, and promoting the activities of caspase-3 and caspase-9. In vivo, ZJW extracts enhanced the inhibiting effect of DDP on tumor growth in SGC-7901/DDP xenograft model and upregulated the expression of p-JNK and Bax but downregulated the Bcl-2 expression in xenograft tumors. In conclusion, in vitro and in vivo, ZJW extracts could enhance the proapoptotic effect of DDP by promoting the activation of JNK and the expression of Bcl-2, inhibiting the Bax expression, followed by increasing the release of Cytochrome C from mitochondria to cytoplasm, and finally activating the caspase cade reaction. Our results implied that ZJW might serve as a synergistic drug with chemotherapeutic drugs DDP in the treatment of gastric cancer.