Cathepsin K deficiency prevented stress-related thrombosis in a mouse FeCl3 model.

BACKGROUND: Exposure to chronic psychological stress (CPS) is a risk factor for thrombotic cardiocerebrovascular diseases (CCVDs). The expression and activity of the cysteine cathepsin K (CTSK) are upregulated in stressed cardiovascular tissues, and we investigated whether CTSK is involved in chronic stress-related thrombosis, focusing on stress serum-induced endothelial apoptosis. METHODS AND RESULTS: Eight-week-old wild-type male mice (CTSK+/+) randomly divided to non-stress and 3-week restraint stress groups received a left carotid artery iron chloride3 (FeCl3)-induced thrombosis injury for biological and morphological evaluations at specific timepoints. On day 21 post-stress/injury, the stress had enhanced the arterial thrombi weights and lengths, in addition to harmful alterations of plasma ADAMTS13, von Willebrand factor, and plasminogen activation inhibitor-1, plus injured-artery endothelial loss and CTSK protein/mRNA expression. The stressed CTSK+/+ mice had increased levels of injured arterial cleaved Notch1, Hes1, cleaved caspase8, matrix metalloproteinase-9/-2, angiotensin type 1 receptor, galactin3, p16IN4A, p22phox, gp91phox, intracellular adhesion molecule-1, TNF-α, MCP-1, and TLR-4 proteins and/or genes. Pharmacological and genetic inhibitions of CTSK ameliorated the stress-induced thrombus formation and the observed molecular and morphological changes. In cultured HUVECs, CTSK overexpression and silencing respectively increased and mitigated stressed-serum- and H2O2-induced apoptosis associated with apoptosis-related protein changes. Recombinant human CTSK degraded γ-secretase substrate in a dose-dependent manor and activated Notch1 and Hes1 expression upregulation. CONCLUSIONS: CTSK appeared to contribute to stress-related thrombosis in mice subjected to FeCl3 stress, possibly via the modulation of vascular inflammation, oxidative production and apoptosis, suggesting that CTSK could be an effective therapeutic target for CPS-related thrombotic events in patients with CCVDs.

Design, synthesis, and evaluation of cyclic C7-bridged monocarbonyl curcumin analogs containing an o-methoxy phenyl group as potential agents against gastric cancer.

The structure-activity relationship (SAR) between toxicity and the types of linking ketones of C7 bridged monocarbonyl curcumin analogs (MCAs) was not clear yet. In the pursuit of effective and less cytotoxic chemotherapeutics, we conducted a SAR analysis using various diketene skeletons of C7-bridged MCAs, synthesized cyclic C7-bridged MCAs containing the identified low-toxicity cyclopentanone scaffold and an o-methoxy phenyl group, and assessed their anti-gastric cancer activity and safety profile. Most compounds exhibited potent cytotoxic activities against gastric cancer cells. We developed a quantitative structure-activity relationship model (R2 > 0.82) by random Forest method, providing important information for optimizing structure. An optimized compound 2 exhibited in vitro and in vivo anti-gastric cancer activity partly through inhibiting the AKT and STAT3 pathways, and displayed a favorable in vivo safety profile. In summary, this paper provided a promising class of MCAs and a potential compound for the development of chemotherapeutic drugs.

Synthesis and Anti-gastric Cancer Activity by Targeting FGFR1 Pathway of Novel Asymmetric Bis-chalcone Compounds.

BACKGROUP: Bis-chalcone compounds with symmetrical structures, either isolated from natural products or chemically synthesized, have multiple pharmacological activities. Asymmetric Bis-chalcone compounds have not been reported before, which might be attributed to the synthetic challenges involved, and it remains unknown whether these compounds possess any potential pharmacological activities. AIMS: The aim of this study is to investigate the synthesis route of asymmetric bis-chalcone compounds and identify potential candidates with efficient anti-tumor activity. METHOD: The two-step structural optimization of the bis-chalcone compounds was carried out sequentially, guided by the screening of the compounds for their growth inhibitory activity against gastric cancer cells by MTT assay. The QSAR model of compounds was established through random forest (RF) algorithm. The activities of the optimal compound J3 on growth inhibition, apoptosis, and apoptosis-inducing protein expression in gastric cancer cells were investigated sequentially by colony formation assay, flow cytometry, and western blotting. Further, the inhibitory effects of J3 on the FGFR1 signaling pathway were explored by Wester Blotting, siRNA, and MTT assays. Finally, the in vivo anti-tumor activity and mechanism of J3 were studied through nude mouse xenograft assay, western blotting. RESULT: 27 asymmetric bis-chalcone compounds, including two types (N and J) were sequentially designed and synthesized. Some N-class compounds have good inhibitory activity on the growth of gastric cancer cells. The vast majority of J-class compounds optimized on the basis of N3 exhibit excellent inhibitory activity on gastric cancer cell growth. We established a QSAR model (R2 = 0.851627) by applying random forest algorithms. The optimal compound J3, which has better activity, concentration-dependently inhibited the formation of gastric cancer cell colonies and led to cell apoptosis by inducing the expression of the pro-apoptotic protein cleaved PARP. J3 may exert anti-gastric cancer effects by inhibiting the activation of FGFR1/ERK pathway. Moreover, at a dose of 10 mg/kg/day, J3 inhibited tumor growth in nude mice by nearly 70% in vivo with no significant toxic effect on body weight and organs. CONCLUSION: In summary, this study outlines a viable method for the synthesis of novel asymmetric bischalcone compounds. Furthermore, the compound J3 demonstrates substantial promise as a potential candidate for an anti-tumor drug.

Discovery of Pyroptosis-inducing Drugs and Antineoplastic Activity Based on the ROS/ER Stress/Pyroptosis Axis.

BACKGROUND: Pyroptosis, a cell death process triggered by chemotherapy drugs, has emerged as a highly promising mechanism for combating tumors in recent years. As the lead of new drugs, natural products play an important role in the discovery of anticancer drugs. Compared to other natural products, the medicine food homologous natural products (MFHNP) exhibit a superior safety profile. Among a series of MFHNP molecular skeletons, this study found that only benzylideneacetophenone (1) could induce cancer cell pyroptosis. However, the anti-cancer activity of 1 remains to be improved. AIMS: This study aimed to find a pyroptosis inducer with highly effective antitumor activity by modifying the chalcone structure. METHODS: To examine the effect of the Michael receptor in compound 1 on the induction of pyroptosis, several analogs were synthesized by modifying the Michael acceptor. Subsequently, the anticancer activity was tested by MTT assay, and morphological indications of pyroptosis were observed in human lung carcinoma NCI-H460 and human ovarian cancer CP-70 cell lines. Furthermore, to improve the activity of the chalcone skeleton, the anticancer group 3,4,5- trimethoxyphenyl was incorporated into the phenyl ring. Subsequently, compounds 2-22 were designed, synthesized, and screened in human lung cancer cells (NCI-H460, H1975, and A549). Additionally, a quantitative structure-activity relationship (QSAR) model was established using the eXtreme Gradient Boosting (XGBoost) machine learning library to identify the pharmacophore. Furthermore, both in vitro and in vivo experiments were conducted to investigate the molecular mechanisms of pyroptosis induced by the active compound. RESULTS: α, ß-unsaturated ketone was the functional group of the chalcone skeleton and played a pivotal role in inducing cancer cell pyroptosis. QSAR models showed that the regression coefficients (R2) were 0.992 (A549 cells), 0.990 (NCI-H460 cells), and 0.998 (H1975 cells). Among these compounds, compound 7 was selected to be the active compound. Moreover, compound 7 was found to induce pyroptosis in lung cancer cells by upregulating the expression of CHOP by increasing the ROS level. Furthermore, it effectively suppressed the growth of lung cancer xenograft tumors. CONCLUSION: Compound 7 exhibits antineoplastic activity by regulating the ROS/ER stress/pyroptosis axis and is a kind of promising pyroptosis inducer.