In traditional Chinese medicine (TCM), Zuogui Wan (ZGW) is a classical prescription for senile disorders and delay aging. Modern studies show that ZGW promotes central nerve cell regeneration, prevents and cures osteoporosis, enhances the body's antioxidant capacity, regulates the body's immune function, and promotes mesenchymal stem cells (MSCs) proliferation. It has been shown that MSCs aging is closely associated with organism's aging and age-related disorders. The study aimed to define the effects of ZGW on the aging bone marrow mesenchymal stem cells (BMSCs) and to identify the mechanisms of ZGW delaying BMSCs senescence. Network pharmacology analysis combined with GEO data mining, molecular docking and experimental validation were used to evaluate the mechanisms by which ZGW delays MSCs senescence (MSCS). LC-MS was used for quality control analysis of ZGW. PPI network analysis revealed that EGF, TNF, JUN, MMPs, IL-6, MAPK8, and MYC are components of the core PPI network. GO and KEGG analyses revealed that oxidative stress, regulation of response to DNA damage stimuli, and Wnt signaling were significantly enriched. GEO database validation also indicated that Wnt signaling closely correlated with MSCs aging. Molecular docking analysis of the top-13 active components in the "ZGW-Targets-MSCS" network indicated that most components have strong affinity for key proteins in Wnt signaling, suggesting that modulation of Wnt signaling is an important mechanism of ZGW activity against MSCS. Further experimental validation found that ZGW indeed regulates Wnt signaling and suppresses the expression of age-related factors to enhance cell proliferation, ameliorate DNA damage, and reduce senescence-related secretory phenotype (SASP) secretion, thereby maintaining multidirectional differentiation of rat BMSCs. Similar results were obtained using the Wnt inhibitor, XAV-939. Together, our data show that ZGW slows BMSCs aging by suppressing Wnt signaling.
Compound Dihuang Granule (CDG) is widely used in traditional Chinese medicine (TCM) for the treatment of Parkinson’s disease (PD). It has been shown to alleviate PD symptoms. However, the molecular mechanisms of its action have not been established. To establish the molecular mechanisms of CDG against PD, we used TCM network pharmacology methods to predict its molecular targets and signaling pathways, followed by experimental validation. The Core Protein protein interaction (PPI) network of the 150 intersections between CDG and PD-related genes, comprising 23 proteins, including CASP3 (caspase-3), MAPK8 (JNK), FOS (c-Fos), and JUN (c-Jun). KEGG and GO analyses revealed that apoptotic regulation and MAPK signaling pathways were significantly enriched. Since c-Jun and c-Fos are AP-1 subunits, an important downstream JNK effector, we investigated if the JNK/AP-1 pathway influences CDG against apoptosis through the nigrostriatal pathways in PD rat models. Molecular docking analysis found that the top three bioactive compounds exhibiting the highest Degree Centrality following online database and LC-MS analysis had high affinities for JNK. Experimental validation analysis showed that CDG decreased the number of rotating laps and suppressed the levels of phosphorylated c-Jun, c-Fos, and JNK, as well as the number of TUNEL positive cells and the cleaved caspase-3 level in the nigrostriatal pathway. Furthermore, CDG treatment elevated the number of TH neurons, TH expression level, and Bcl-2/Bax protein ratio in a 6-OHDA-induced PD rat. These findings are in tandem with those obtained using SP600125, a specific JNK inhibitor. In conclusion, CDG suppresses the apoptosis of the nigrostriatal pathway and relieves PD symptoms by suppressing the JNK/AP-1 signaling pathway.