Wogonoside Ameliorates Airway Inflammation and Mucus Hypersecretion via NF-κB/STAT6 Signaling in Ovalbumin-Induced Murine Acute Asthma.

Asthma is recognized as a chronic respiratory illness characterized by airway inflammation and airway hyperresponsiveness. Wogonoside, a flavonoid glycoside, is reported to significantly alleviate the inflammation response and oxidative stress. Herein, this study aimed to investigate the therapeutic effect and underlying mechanism of wogonoside on airway inflammation and mucus hypersecretion in a murine asthma model and in human bronchial epithelial cells (16HBE). BALB/c mice were sensitized and challenged with ovalbumin (OVA). Pulmonary function and the number of cells in the bronchoalveolar lavage fluid (BALF) were examined. Pathological changes in lung tissue in each group were evaluated via hematoxylin and eosin and periodic acid-Schiff staining, and changes in levels of cytokines in BALF and of immunoglobulin E in serum were determined via an enzyme-linked immunosorbent assay. The expression of relevant genes in lung tissue was analyzed via real-time PCR. Western blotting and immunofluorescence were employed to detect the expression of relevant proteins in lung tissue and 16HBE cells. Treatment with 10 and 20 mg/kg wogonoside significantly attenuated the OVA-induced increase of inflammatory cell infiltration, mucus secretion, and goblet cell percentage and improved pulmonary function. Wogonoside treatment reduced the level of T-helper 2 cytokines including interleukin (IL)-4, IL-5, and IL-13 in BALF and of IgE in serum and decreased the mRNA levels of cytokines (IL-4, IL-5, IL-6, IL-13, and IL-1ß and tumor necrosis factor-α), chemokines (CCL-2, CCL-11, and CCL-24), and mucoproteins (MUC5AC, MUC5B, and GOB5) in lung tissues. The expression of MUC5AC and the phosphorylation of STAT6 and NF-κB p65 in lung tissues and 16HBE cells were significantly downregulated after wogonoside treatment. Thus, wogonoside treatment may effectively decrease airway inflammation, airway remodeling, and mucus hypersecretion via blocking NF-κB/STAT6 activation.

Identification of Gossypol Acetate as an Autophagy Modulator with Potent Anti-tumor Effect against Cancer Cells.

Autophagy, an evolutionarily conserved process, is intricately involved in many aspects of human health and a variety of human diseases, including cancer. Discovery of small-molecule autophagy modulators with potent anticancer effect would be of great significance. To this end, a natural product library consisting of 170 natural compounds were screened as autophagy modulators with potent cytotoxicity in our present study. Among these compounds, gossypol acetate (GAA), the mostly used medicinal form of gossypol, was identified. GAA effectively increased the number of autophagic puncta in GFP-LC3B-labeled 293T cells and significantly decreased cell viability in different cancer cells. In A549 cells, GAA at concentrations below 10 µM triggered caspase-independent cell death via targeting autophagy, as evidenced by elevated LC3 conversion and decreased p62/SQSTM1 levels. Knocking down of LC3 significantly attenuated GAA-induced cell death. Mechanistically, GAA at low concentrations induced autophagy through targeting AMPK-mTORC1-ULK1 signaling. Interestingly, high concentrations of GAA induced LC3 conversion, p62 accumulation, and yellow autophagosome formation, indicating that GAA at high concentrations blocked autophagic flux. Mechanistically, GAA decreased intracellular ATP level and suppressed lysosome activity. Exogenous ATP partially reversed the inhibitory effect of GAA on autophagy, suggesting that decreased ATP level and lysosome activity might be involved in the blocking of autophagy flux by GAA. Collectively, our present study reveals the mechanisms by which GAA modulates autophagy and illustrates whether autophagy regulation by GAA is functionally involved in GAA-induced cancer cell death.

Lipid Droplet-Specific Probe for Rapidly Locating Atherosclerotic Plaques and Intraoperative Imaging via In Situ Spraying.

The ability to visualize the full extent of atherosclerotic plaques during surgery has major implications for therapeutic outcomes. Fluorescence imaging is a promising approach for atherosclerotic plaque inspection during surgery. However, a specific strategy for the intraoperative fluorescence imaging of atherosclerosis has not been established. This study presents an in situ spraying aerosol of a lipid droplet-specific probe to rapidly and precisely locate atherosclerotic plaques during surgery. Stable imaging of the plaque was achieved within 5 min by nebulizing the aqueous solution of the lipid droplet-specific probe (CN-PD) into 3 µm droplets and rapidly permeating it in situ. The visible fluorescence bioimaging of CN-PD can accurately delineate the plaque margins and size even with a diameter ≤0.5 mm, which are capable of being swiftly captured during the stable plaque imaging window (>2 h). This strategy combines the consideration of a specific probe design and an efficient in situ delivery, which results in weak interference from the background signals. Therefore, the plaque-to-normal tissue ratio (P/N) is sufficient to facilitate the surgical delineation of carotid atherosclerotic plaques. The originality of the intraoperative fluorescence imaging of the plaques via in situ delivery of the lipid droplet-specific probe holds promise for effective clinical application.

Parthenolide inhibits ubiquitin-specific peptidase 7 (USP7), Wnt signaling, and colorectal cancer cell growth.

It has been well-established that the deubiquitinating enzyme ubiquitin-specific peptidase 7 (USP7) supports cancer growth by up-regulating multiple cellular pathways, including Wnt/ß-catenin signaling. Therefore, considerable efforts are directed at identifying and developing USP7 inhibitors. Here, we report that sesquiterpene lactone parthenolide (PTL) inhibits USP7 activity, assessed with deubiquitinating enzyme activity assays, including fluorogenic Ub-AMC/Ub-Rho110, Ub-VME/PA labeling, and Di-Ub hydrolysis assays. Further investigations using cellular thermal shift (CETSA), surface plasmon resonance (SPR), and mass spectrum (MS) assays revealed that PTL directly interacts with USP7. Consistent with the role of USP7 in stimulating Wnt signaling and carcinogenesis, PTL treatment inhibited the activity of Wnt signaling partly by destabilizing ß-catenin. Moreover, using cell viability assays, we found that PTL suppresses the proliferation of colorectal cancer cells and induces apoptosis in these cells. Additionally, we examined the effects of two other sesquiterpene lactones (costunolide and α-santonin) on USP7 and Wnt signaling and found that α-methylene-γ-butyrolactone may provide a scaffold for future USP7 inhibitors. In summary, our findings reveal that PTL inhibits USP7 activity, identifying a potential mechanism by which PTL suppresses Wnt/ß-catenin signaling. We further suggest that sesquiterpene lactones might represent a suitable scaffold for developing USP7 inhibitors and indicate that PTL holds promise as an anticancer agent targeting aberrant USP7/Wnt signaling.

Synthesis and antitumor activity of aza-brazilan derivatives containing imidazolium salt pharmacophores.

The synthesis of a series of novel aza-brazilan derivatives containing imidazolium salt pharmacophores is presented. The biological activity of such imidazolium salts was further evaluated in vitro against a panel of human tumor cell lines. The results suggest that the electron-withdrawing group on the aza-brazilan moiety, substituted 5,6-dimethyl-benzimidazole ring and substitution of the imidazolyl-3-position with a 4-methylbenzyl group were essential for modulating the cytotoxic activity. Compounds 55 and 39, bearing a 4-methylbenzyl substituent at position-3 of 5,6-dimethyl-benzimidazole, were found to be the most potent compounds with IC50 values of 0.52-1.30 µM and 0.56-1.51 µM against four human tumor cell lines investigated. Particularly, compound 57 exhibited inhibitory activity against the MCF-7 cell line with an IC50 value of 0.35 µM and was 56-fold more sensitive than DDP. Moreover, compound 55 inhibited cell proliferation through inducing G0/G1 cell cycle arrest and apoptosis in SMMC-7721 cells.