Cycloastragenol: A Novel Senolytic Agent That Induces Senescent Cell Apoptosis and Restores Physical Function in TBI-Aged Mice.

Accumulating evidence indicates that the increased burden of senescent cells (SCs) in aged organisms plays an important role in many age-associated diseases. The pharmacological elimination of SCs with "senolytics" has been emerging as a new therapy for age-related diseases and extending the healthy lifespan. In the present study, we identified that cycloastragenol (CAG), a secondary metabolite isolated from Astragalus membrananceus, delays age-related symptoms in mice through its senolytic activity against SCs. By screening a series of compounds, we found that CAG selectively kills SCs by inducing SCs apoptosis and that this process is associated with the inhibition of Bcl-2 antiapoptotic family proteins and the PI3K/AKT/mTOR pathway. In addition, CAG treatment also suppressed the development of the senescence-associated secretory phenotype (SASP) in SCs, thereby inhibiting cell migration mediated by the SASP. Furthermore, the administration of CAG for 2 weeks to mice with irradiation-induced aging alleviated the burden of SCs and improved the animals' age-related physical dysfunction. Overall, our studies demonstrate that CAG is a novel senolytic agent with in vivo activity that has the potential to be used in the treatment of age-related diseases.

Indole Hydrazide Compound IHZ-1 Induces Apoptosis and Autophagy via Activation of ROS/JNK Pathway in Hepatocellular Carcinoma.

Hepatocellular carcinoma is one of the most common primary malignant tumors of the digestive system. Compound 5-chloro-N'-(2,4-dimethoxybenzylidene)-1H-indole-2-carbohydrazide (IHZ-1/ZJQ-24) is a novel indole hydrazide derivative. In a recent study, we demonstrated that IHZ-1 inhibits tumor growth and induces cell apoptosis through inhibiting the kinase activity of mTORC1 without activation of AKT, which is associated with JNK/IRS-1 activation. However, the impact and mechanisms of JNK activation by IHZ-1 in hepatocellular carcinoma remains entirely unknown. Here, we find that IHZ-1 increases the generation of intracellular ROS and enhances autophagy. The phosphorylation of JNK induced by IHZ-1 was reversed by the decreased ROS level. Moreover, inhibition of ROS/JNK or autophagy equally attenuated apoptotic effect induced by IHZ-1. Our findings suggest that the activation of JNK by IHZ-1 treatment is dependent on the generation of ROS that mediates apoptosis and autophagy in hepatocellular carcinoma.