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• This work demonstrates for the first time that LGS exerts anti-DENV-2 activity in the early stage of DENV-2 infection in vitro. • LGS decreases DENV-2-stimulated cytoplasmic Hsp70 translocation into the plasma membrane by Cav1 inhibition, thereby inhibiting the early stage of virus infection in DENV-2-infected Huh7 cells. • In mice model infected with the DENV-2, LGS was effective in prolonging the survival time, reducing viral loads. Dengue virus (DENV) is a major public health threat. However, there are no specific therapeutic drugs for DENV. Many Chinese heat-cleaning formulas, such as Liang-Ge-San (LGS), have been frequently used in the virus-induced diseases. The antiviral effect of LGS has not been reported yet. In this study, the effect of LGS on the inhibition of dengue virus serotype 2 (DENV-2) was investigated and the relevant mechanism was explored. High-performance liquid chromatography was applied to analyze the chemical characterization of LGS. The in vitro antiviral activities of LGS against DENV-2 were evaluated by time-of-drug-addition assay. The binding of heat shock protein 70 (Hsp70) and envelope (E) protein or caveolin1 (Cav1) were analyzed by immunofluorescence and immunoprecipitation assays. Then the role of Cav1 in the anti-DENV-2 effects of LGS was further examined. DENV-2 infected Institute of Cancer Research suckling mice (n = 10) and AG129 mice (n = 8) were used to examine the protective effects of LGS. It was found that geniposide, liquiritin, forsythenside A, forsythin, baicalin, baicalein, rhein, and emodin maybe the characteristic components of LGS. LGS inhibited the early stage of DENV-2 infection, decreased the expression levels of viral E and non-structural protein 1 (NS1) proteins. LGS also reduced E protein and Hsp70 binding and attenuated the translocation of Hsp70 from cytoplasm to the cell membrane. Moreover, LGS decreased the binding of Hsp70 to Cav1. Further study showed that the overexpression of Cav1 reversed LGS-mediated E protein and Hsp70 inhibition in the plasma membrane. In the in vivo study, LGS was highly effective in prolonging the survival time, reducing viral loads. This work demonstrates for the first time that LGS exerts anti-DENV-2 activity in vitro and in vivo. LGS decreases DENV-2-stimulated cytoplasmic Hsp70 translocation into the plasma membrane by Cav1 inhibition, thereby inhibiting the early stage of virus infection. These findings indicate that LGS may be a candidate for the treatment of DENV. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) ranks third among the most common causes of cancer-related deaths worldwide. The chemotherapy for HCC is still insufficient, so far. In searching for effective anti-HCC agents from traditional Chinese medicine, we discovered that aloperine (ALO), a quinolizidine alkaloid from Sophora alopecuroides L., exerts anti-HCC activities. However, the effects of ALO on HCC have been rarely studied, and its underlying mechanisms remain unknown.Purpose: This study aims to evaluate the anti-HCC activities of ALO and explore its underlying mechanisms.Methods: MTT assay and colony formation assay were used to investigate the anti-proliferative effects of ALO on human HCC Hep3B and Huh7 cells. Hoechst 33258 staining was used to observe the morphological changes of cells after ALO treatment. Flow cytometry was used to analyze apoptosis induction, the collapse of the mitochondrial membrane potential and cell cycle distribution. Western blotting was used to examine the expression levels of proteins associated with apoptosis and cell cycle arrest, and key proteins in the PI3K/Akt signaling pathway. Small interfering RNA (siRNA) transfection was used to investigate the role of Akt in ALO-induced apoptosis and cell cycle arrest. Zebrafish tumor model was used to evaluate the anti-HCC effects of ALO in vivo.Results: ALO inhibited the proliferation of Hep3B and Huh7 cells. ALO induced apoptosis in HCC cells, which was accompanied by the loss of mitochondrial potential, the release of cytochrome c into cytosol, as well as the increased cleavages of caspase-9, caspase-3 and PARP. Moreover, ALO induced G2/M cell cycle arrest by downregulating the expression levels of cdc25C, cdc2 and cyclin B1. In addition, ALO inhibited activation of the PI3K/Akt signaling pathway by decreasing the expression levels of p110α, p85, Akt and p-Akt (Ser473). Further study showed that inhibition of Akt by siRNA augmented ALO-mediated apoptosis and G2/M cell cycle arrest in HCC cells. Critically, ALO inhibited the growth of Huh7 cells in vivo.Conclusion: We first demonstrated that ALO induced apoptosis and G2/M cell cycle arrest in HCC cells through inhibition of the PI3K/Akt signaling pathway. This study provides a rationale for ALO as a potential chemotherapeutic agent for HCC. [ABSTRACT FROM AUTHOR]