Background: Baicalein, a natural flavonoid derived from traditional Chinese herb Scutellaria baicalensis Georg (known as Huang Qin in Chinese), has been reported to exhibit notable antitumor activity in various cancer cells, including breast cancer. However, the detailed mechanisms underlying its induced apoptosis as a prooxidant in breast cancer cells are still unknown. Materials and methods: In this study, we investigated the effect of endogenous copper on cytotoxic activity of baicalin against human breast cancer MCF-7 cells in vitro. Results: Baicalein could remarkably reduce the cell viability in both dose- and time-dependent manners in MCF-7 cells but with lower cytotoxic effects on normal breast epithelial cells, MCF-10A. Such cell death could be prevented by pretreatment with Cu (I)-specific chelator neocuproine (Neo) and reactive oxygen species (ROS) scavengers. Meanwhile, baicalein could induce MCF-7 cell morphological changes, promote apoptotic cell death and increase the apoptotic cell number. Moreover, DCHF-DA staining, flow cytometry and Western blotting analyses proved that baicalein triggered the mitochondrial-dependent apoptotic pathway, as indicated by enhancement the level of intracellular ROS, disruption of mitochondrial membrane potential (ΔΨm), downregulation of anti-apoptotic protein Bcl-2, upregulation of pro-apoptotic protein Bax, release of cytochrome C and activation of caspase-9 and caspase-3 in MCF-7 cells. The pretreatment with Neo remarkably weakened these effects of baicalein. Furthermore, we confirmed that the prooxidant action of baicalein involved the direct production of hydroxyl radicals through redox recycling of copper ions. Conclusion: These findings suggested that baicalein, acting as a prooxidant, could trigger apoptosis in MCF-7 cells occurs via the ROS-mediated intrinsic mitochondria-dependent pathway.

Stems are the important residues of Trapa quadrispinosa Roxb., which are abundant in phenolic compounds. Ultrasonic-assisted enzymatic extraction (UAEE) is confirmed as a novel extraction technology with main advantages of enhancing extraction yield and physiological activities of the extracts from various plants. In this study, UAEE was applied to obtain the highest yield of phenolic content, strongest antioxidant, and antitumor activities and to optimize the extraction conditions using response surface methodology (RSM). The extracts from the stems of T. quadrispinosa were characterized by determination of their antioxidant activities through 2,2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS), 1,1-Diphenyl-2-picrylhydrazxyl (DPPH) radical scavenging, total antioxidant capacity (TAC), ferric reducing antioxidant capacity (FRAC) methods and of their antitumor activity by MTT method. The selected key independent variables were cellulase concentration (X₁: 1.5%–2.5%), extraction time (X₂: 20–30 min) and extraction temperature (X₃: 40–60 °C). The optimal extraction conditions for total phenolic content (TPC) value of the extracts were determined as 1.74% cellulase concentration, 25.5 min ultrasonic extraction time and 49.0 °C ultrasonic temperature. Under these conditions, the highest TPC value of 53.6 ± 2.2 mg Gallic acid equivalent (GAE)/g dry weight (DW) was obtained, which agreed well with the predicted value (52.596 mg GAE/g·DW. Furthermore, the extracts obtained from UAEE presented highest antioxidant activities through ABTS, DPPH, TAC and FRAC methods were of 1.54 ± 0.09 mmol Trolox equivalent (TE)/g·DW; 1.45 ± 0.07 mmol·TE/g·DW; 45.2 ± 2.2 mg·GAE/g·DW; 50.4 ± 2.6 μmol FeSO₄ equivalent/g·DW and lowest IC₅₀ values of 160.4 ± 11.6 μg/mL, 126.1 ± 10.8 μg/mL, and 178.3 ± 13.1 μg/mL against Hela, HepG-2 and U251 tumor cells, respectively. The results indicated that the UAEE was an efficient alternative to improve extraction yield and enhance the antioxidant and antitumor activities of the extracts. The phenolic extracts from the stems of T. quadrispinosa had significant antioxidant and antitumor activities, which could be used as a source of potential antioxidant and antitumor agents.

Background: Rattan tea is a medicinal plant that has been used for many years for the treatment of inflammation, fatty liver, tumor, diabetes, and hyperlipidemia. Objective: A green and novel approach based on surfactant-mediated, ultrasonic-assisted extraction (SM-UAE) was developed for the extraction of antioxidant polyphenols from Rattan tea. A nonionic surfactant Tween-80 was selected as extraction solvent. The antioxidant activity was measured by total phenolic content (TPC) and ferric-reducing/antioxidant capacity (FRAC) assay. Materials and Methods: Optimization of extraction parameters including concentration of solvent, ultrasonic time, and temperature were investigated by response surface methodology. The antioxidant activity was measured by TPC and FRAC assay. Results: The optimal extraction conditions were determined as 6.8% (v/v) of aqueous Tween-80, ultrasonic temperature of 54°C, and ultrasonic time of 28.8 min. Under these conditions, the highest TPC value of 360.4 mg gallic acid equivalent per gram of dry weight material (GAE/g DW) was recorded. Moreover, 6.8% (v/v) of aqueous Tween-80, ultrasonic temperature of 54.5°C, and ultrasonic time of 28.4 min were determined for the highest FRAC value of 478.2 μmol of Fe²⁺/g of weight material (μmol Fe²⁺/g DW). Compared with other methods, the TPC and FRAC values of 313.5 mg GAE/g DW and 389.6 μmol Fe²⁺/g DW were obtained by heat reflux extraction using ethanol as solvent, respectively, and 343.2 mg GAE/g DW and 450.1 μmol Fe²⁺/g DW were obtained by UAE using ethanol as solvent, respectively. Conclusion: The application of SM-UAE markedly decreased extraction time or extraction cost and improved the extraction efficiency, compared with the other methods. Abbreviations used: SM-UAE: Surfactant-mediated ultrasonic-assisted extraction; TPC: total phenolic content; FRAC: Ferric reducing antioxidant capacity; RSM: Response surface methodology; BBD: Box-Behnken design.

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death in the world. Hepatitis B virus (HBV) and its X gene-encoded protein (HBx) play important roles in the progression of HCC. Although long non-coding RNAs (lncRNAs) cannot encode proteins, growing evidence indicates that they play essential roles in HCC progression, and contribute to cell proliferation, invasion and metastasis, autophagy, and apoptosis by targeting a large number of pivotal protein-coding genes, miRNAs, and signaling pathways. In this review, we briefly outline recent findings of differentially expressed lncRNAs in HBV-related HCC, with particular focus on several key lncRNAs, and discuss their regulation by HBV/HBx, their functions, and their underlying molecular mechanisms in the progression of HCC.

Cu and O co-doped porous g-C ₃ N ₄ with outstanding photocatalytic degradation of levofloxacin performance was synthesized by a one-pot thermal polymerization approach.