RESUMO
Sedum sarmentosum (Sedi Herba) has traditionally been used to treat jaundice and various types of liver disease. This study aimed to clarify the anti-cholestatic efficacy and the mechanism of S. sarmentosum ethyl acetate extract (SDEAE), as well as to screen the potential compounds with FXR activation. SDEAE effectively ameliorated ANIT-induced cholestasis in rats, as evidenced by the ameliorative histopathology of the liver and the significant decrease in biochemical markers (ALT, AST, ALP, GGT, TBIL, DBIL and TBA). The analysis of bile acid profile by LC-MS indicated that SDEAE decreased the toxic bile acid levels (TCA, TMCA and CA). Western blotting indicated that SDEAE activated FXR-associated pathway, thereby upregulating FXR, SHP, BSEP and UGT2B4 expression, and downregulating CYP7A1 and NTCP expression. Twenty-three compounds (7 nor-sesquiterpenoids, 13 flavonoids, 1 lignin, 1 sterol and 1 anthraquinone) were isolated and identified from SDEAE by comparing NMR data with the literature. The HPLC profiles of SDEAE and isolated compounds were also compared. High-content analysis showed that eight compounds (6, 7, 8, 11, 12, 13, 14 and 23) could activate FXR and compound 8 exhibited the most potent activity (p < 0.01). Molecular docking suggested that the main binding modes between these active compounds and FXR were hydrogen bonding and van der Waals forces, and compound 8 had the highest docking score 6.34. The activation of compound 8 on FXR-mediated signaling was validated in L02 cells. After siRNA down-regulation of FXR, compound 8 significantly elevated FXR, SHP, BSEP and UGT2B4 expression, and reduced CYP7A1 and NTCP expression.
Assuntos
Colestase , Sedum , Ratos , Animais , Simulação de Acoplamento Molecular , RNA Interferente Pequeno/metabolismo , Lignina/metabolismo , Colestase/induzido quimicamente , Colestase/tratamento farmacológico , Fígado , Ácidos e Sais Biliares/metabolismo , Flavonoides/farmacologia , Antraquinonas/farmacologia , Esteróis/metabolismoRESUMO
Bispecific T-cell engager antibodies (BiTE) have been explored as a means to recruit cytolytic T cells to kill tumor cells. The transferrin receptor (TfR) is highly expressed on the surface of rapidly proliferating tumor cells. Therefore, it holds great potential in T cell redirecting therapies. In this research, we developed a BiTE targeting TfR and CD3 (TfR-BiTE) and studied its therapeutic impact on TfR-positive cancer. TfR-BiTE had the ability to induce the selective lysis of various TfR-positive cancer cells through the activation of T cells, the release of cytokines, and then the coming proliferation of T cells, whereas TfR-negative cells were not affected. In a subcutaneous HepG2 xenograft model, low concentrations of TfR-BiTE inhibited tumor growth. Overall, these results reveal that TfR-BiTE can selectively deplete TfR-positive HepG2 cells; hence, it represents a novel immunotherapeutic approach for the treatment of hepatocellular carcinoma.
Assuntos
Anticorpos Biespecíficos/farmacologia , Complexo CD3/antagonistas & inibidores , Imunoterapia/métodos , Neoplasias Experimentais/imunologia , Receptores da Transferrina/antagonistas & inibidores , Linfócitos T Citotóxicos/imunologia , Animais , Células Hep G2 , Humanos , Ativação Linfocitária/imunologia , Camundongos , Linfócitos T Citotóxicos/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Many previous event-related potential (ERP) studies have linked the feedback related negativity (FRN) component with medial frontal cortex processing and associated this component with depression. Few if any studies have investigated the processing of neutral feedback in mildly depressive subjects in the normal population. Two experiments compared brain responses to neutral feedback with behavioral performance in mildly depressed subjects who scored highly on the Beck Depression Inventory (high BDI) and a control group with lower BDI scores (low BDI). In the first study, the FRN component was recorded when neutral, negative or positive feedback was pseudo-randomly delivered to the two groups in a time estimation task. In the second study, real feedback was provided to the two groups in the same task in order to measure their actual accuracy of performance. The results of experiment one (Exp. 1) revealed that a larger FRN effect was elicited by neutral feedback than by negative feedback in the low BDI group, but no significant difference was found between neutral condition and negative condition in the High BDI group. The present findings demonstrated that depressive tendencies influence the processing of neutral feedback in medial frontal cortex. The FRN effect may work as a helpful index for investigating cognitive bias in depression in future studies.