Objective: With Persicaria capitata as test materials, we compared and analyzed the chloroplast (cp) genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Persicaria nepalensis, Persicaria japonica, Persicaria chinensis, Persicaria filiformis, Persicaria perfoliata, Persicaria pubescens, Persicaria hnydropiper. Methods: The Illumina HiSeq high-throughput sequencing platform was used for the first time for P. capitata cp genome sequencing. NOVOPlasty and CpGAVAS2 were used for assembly and annotation, and Codon W, DnaSP, and MISA were used to conduct a series of comparative genomic analyses between the plant and seven species of the same genus. A phylogenetic tree was constructed using the maximum likelihood (ML) and neighbor-joining (NJ) methods, and divergence time was estimated using BEAST. Results: The total length of P. capitata cp genome was 158,821 bp, with a guanine and cytosine (GC) content of 38.0%, exhibiting a typical circular tetrad structure. The genome contains 127 annotated genes, including 82 protein-coding and 45 tRNA-encoding genes. The cp genome harbors simple sequence repeat (SSR) loci primarily composed of A/T. The conserved species structure of this genus is reinforced by the expansion and contraction of the inverted repeat (IR) region. The non-coding regions of the cp genomes exhibited significant differences among the genera. Six different mutation hotspots (psbK-psbI, atpI-rps2, petN-psbD, atpB-rbcL, cemA-petA, ndhI-ndhA-ycf1) were screened from the non-coding regions of genes with high nucleotide variability (pI). These hotspots were expected to define the phylogenetic species of Persicaria. Furthermore, phylogenetic analysis of Polygonaceae plants showed that P. capitata was more closely related to P. chinensis than P. nepalensis. Analysis of divergence time indicated that Polygonaceae originated in the Late Cretaceous (~180 Ma) and began to differentiate during the Middle Miocene. Persicaria differentiated ~66.44 million years ago, during the Miocene. Conclusions: Our findings will serve as a scientific basis for further research on species identification and evolution, population genetics, and phylogenetic analysis of P. capitata. Further, we provide valuable information for understanding the origin and evolution of Persicaria in Polygonaceae and estimating the differentiation time of Persicaria and its population.

Pulmonary fibrosis (PF) is a serious interstitial disease that includes diffuse collagen deposition of lung tissue. Polygonum capitatum Buch.-Ham. ex D. Don (THL) is a traditional vaccine that has antibacterial and anti-inflammatory effects. In this research, to investigate the mechanism of action of THL in the intervention of pulmonary fibrosis by network pharmacology and molecular docking related research methods, in order to provide a theoretical basis for expanding the scope of THL medication. A total of 49 active ingredients were analyzed and screened in Cephalus cephalusis, including 35 pulmonary fibrosis targets, and 10 key targets such as ALB, EGFR were screened after software analysis. The molecular docking results showed that there were 44 binding energies less than –3 kcal·mol⁻¹ in the 60 docking results, indicating that most proteins had strong binding energies with compounds. The key targets of KEGG enrichment analysis were mainly enriched in 20 core action pathways, such as hemostasis-related pathway, regulation of kinase activity. This study shows that based on network pharmacology, the multicomponent–multitarget–multipathway effect of THL intervention in pulmonary fibrosis is discussed.

The present study utilizes network pharmacology and molecular docking methodologies to investigate the mechanism of action behind the intervention of Polygonum capitatum Buch.-Ham.ex D. Don (THL) in treating pulmonary nodules (PN). This research aims to provide a theoretical foundation for broadening the clinical application of THL. Active components of THL were identified and screened through an extensive literature review and the PharmMapper database, followed by an analysis of their target interactions. Relevant targets associated with PN were selected using databases such as OMIM and GeneCards, with an intersection of the two sets being determined. STRING11.5 facilitated the acquisition of protein-protein interaction data, which was then imported into Cytoscape 3.7.2 to establish a protein interaction network topology. This enabled the identification of pivotal targets affected by THL intervention in PN. The study further employed the Metascape database to conduct GO and KEGG bioinformatics enrichment analyses, which illuminated core pathways involved in THL’s therapeutic effects on PN. A comprehensive component-target-pathway diagram was constructed utilizing Cytoscape 3.7.2 software, with molecular docking validations carried out via Maestro software. A total of 49 active THL ingredients were discerned, implicating 67 PN-relevant targets. Subsequent software analysis pinpointed 10 key targets, including ALB, EGFR, and SRC. Molecular docking studies indicated strong binding affinities for most protein-compound pairs, with 44 out of 60 docking results exhibiting binding energies below −5 kcal/mol. Enrichment analysis highlights that key targets are mainly involved in pathways such as cancer, lipid metabolism and atherosclerosis, estrogen signaling, IL-17 signaling, complement and coagulation cascades, and chemical carcinogenesis through receptor activation. Through comprehensive network pharmacological approaches, this research delineates the synergy of THL’s multiple components, targets, and pathways in mitigating PN. It posits that primary active ingredients of THL – quercetin, salidroside, and oleanolic acid – may exert effects on targets like ALB, EGFR, SRC, potentially modulating pathways associated with cancer, lipid and atherosclerosis, and IL-17 signaling in the context of PN intervention.