ABSTRACT
BACKGROUND: Diabetic kidney disease (DKD) is one of the serious complications of diabetes mellitus, and the existing treatments cannot meet the needs of today's patients. Traditional Chinese medicine has been validated for its efficacy in DKD after many years of clinical application. However, the specific mechanism by which it works is still unclear. Elucidating the molecular mechanism of the Nardostachyos Radix et Rhizoma-rhubarb drug pair (NRDP) for the treatment of DKD will provide a new way of thinking for the research and development of new drugs. AIM: To investigate the mechanism of the NRDP in DKD by network pharmacology combined with molecular docking, and then verify the initial findings by in vitro experiments. METHODS: The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to screen active ingredient targets of NRDP. Targets for DKD were obtained based on the Genecards, OMIM, and TTD databases. The VENNY 2.1 database was used to obtain DKD and NRDP intersection targets and their Venn diagram, and Cytoscape 3.9.0 was used to build a "drug-component-target-disease" network. The String database was used to construct protein interaction networks. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and Gene Ontology analysis were performed based on the DAVID database. After selecting the targets and the active ingredients, Autodock software was used to perform molecular docking. In experimental validation using renal tubular epithelial cells (TCMK-1), we used the Cell Counting Kit-8 assay to detect the effect of NRDP on cell viability, with glucose solution used to mimic a hyperglycemic environment. Flow cytometry was used to detect the cell cycle progression and apoptosis. Western blot was used to detect the protein expression of STAT3, p-STAT3, BAX, BCL-2, Caspase9, and Caspase3. RESULTS: A total of 10 active ingredients and 85 targets with 111 disease-related signaling pathways were obtained for NRDP. Enrichment analysis of KEGG pathways was performed to determine advanced glycation end products (AGEs)-receptor for AGEs (RAGE) signaling as the core pathway. Molecular docking showed good binding between each active ingredient and its core targets. In vitro experiments showed that NRDP inhibited the viability of TCMK-1 cells, blocked cell cycle progression in the G0/G1 phase, and reduced apoptosis in a concentration-dependent manner. Based on the results of Western blot analysis, NRDP differentially downregulated p-STAT3, BAX, Caspase3, and Caspase9 protein levels (P < 0.01 or P < 0.05). In addition, BAX/BCL-2 and p-STAT3/STAT3 ratios were reduced, while BCL-2 and STAT3 protein expression was upregulated (P < 0.01). CONCLUSION: NRDP may upregulate BCL-2 and STAT3 protein expression, and downregulate BAX, Caspase3, and Caspase9 protein expression, thus activating the AGE-RAGE signaling pathway, inhibiting the vitality of TCMK-1 cells, reducing their apoptosis. and arresting them in the G0/G1 phase to protect them from damage by high glucose.
ABSTRACT
BACKGROUND: Diabetic nephropathy (DN) stands as the most prevalent chronic microvascular complication of diabetes mellitus. Approximately 50% of DN patients progress to end-stage renal disease, posing a substantial health burden. AIM: To employ network pharmacology and molecular docking methods to predict the mechanism by which glycyrrhetinic acid (GA) treats DN, subsequently validating these predictions through experimental means. METHODS: The study initially identified GA targets using Pharm Mapper and the TCMSP database. Targets relevant to DN were obtained from the Genecards, OMIM, and TTD databases. The Venny database facilitated the acquisition of intersecting targets between GA and DN. The String database was used to construct a protein interaction network, while DAVID database was used to conducted Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and Gene Ontology (GO) analysis. Molecular docking experiments were performed using Autodock software with selected proteins. Experimental validation was conducted using renal proximal tubular cells (HK-2) as the study subjects. A hyperglycemic environment was simulated using glucose solution, and the effect of GA on cell viability was assessed through the cell counting kit-8 method. Flow cytometry was employed to detect cell cycle and apoptosis, and protein immunoblot (western blot) was used to measure the expression of proteins of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and insulin resistance pathway, including insulin receptor (INSR), PI3K, p-PI3K, AKT, p-AKT, and glycogen synthase kinase-3 (GSK3). RESULTS: A total of 186 intersecting targets between GA and DN were identified, which were associated with 144 KEGG-related enrichment pathways, 375 GO biological process entries, 45 GO cellular component entries, and 112 GO cellular function entries. Molecular docking demonstrated strong binding of GA to mitogen-activated protein kinase (MAPK)-1, SRC, PIK3R1, HSP90AA1, CASPASE9, HARS, KRAS, and MAPK14. In vitro experiments revealed that GA inhibited HK-2 cell viability, induced cell cycle arrest at the G2/M phase, and reduced apoptosis with increasing drug concentration. Western blot analysis showed that GA differentially up-regulated GSK3 protein expression, up-regulated AKT/p-AKT expression, down-regulated INSR, AKT, p-AKT, PI3K, and p-PI3K protein expression, and reduced p-PI3K/PI3K levels under high glucose conditions. CONCLUSION: GA may protect renal intrinsic cells by modulating the PI3K/AKT signaling pathway, thereby inhibiting HK-2 cell viability, reducing HK-2 cell apoptosis, and inducing cell cycle arrest at the G0/G1 phase.
ABSTRACT
Coix seed is a dry and mature seed of Coix lacryma-jobi L.var.ma-yuen (Roman.) Stapf in the Gramineae family. Coix seed has a sweet, light taste, and a cool nature. Coix seed enters the spleen, stomach, and lung meridians. It has the effects of promoting diuresis and dampness, strengthening the spleen to prevent diarrhea, removing arthralgia, expelling pus, and detoxifying and dispersing nodules. It is used for the treatment of edema, athlete's foot, poor urination, spleen deficiency and diarrhea, dampness and obstruction, lung carbuncle, intestinal carbuncle, verruca, and cancer. The medicinal and health value is high, and it has been included in the list of medicinal and food sources in China, which has a large development and application space. This article reviews the current research achievements in the processing methods and anti-tumor activities of Coix seed and provides examples of its clinical application in ancient and modern times, aiming to provide reference for further research on Coix seed and contribute to its clinical application and development. Through the analysis of the traditional Chinese patent medicines, and simple preparations and related health food of Coix seed queried by Yaozhi.com, the source, function, and dosage form of Coix seed were comprehensively analyzed, with a view of providing a reference for the development of Coix seed medicine and food.