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Integrative network pharmacology, transcriptomics, and molecular docking identify candidate Centella asiatica constituents and targets in neurodegenerative diseases.

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  1. # Reproducibility README
  2. This file contains an anonymized and consolidated R workflow for the analyses performed in the manuscript:
  3. **Identification of Potential Bioactive Constituents of *Centella asiatica* for Neurodegenerative Diseases Using Network Pharmacology and Molecular Docking**
  4. The workflow was consolidated from the original analysis scripts used for compound filtering, target prediction integration, disease-gene integration, PCA, differential-expression analysis, GO/KEGG enrichment, network-file construction, machine-learning feature selection, hub-gene expression validation, and ROC analysis.
  5. All local paths and project-specific filenames have been replaced with generic placeholders. Before running the code, replace the placeholder input filenames with the corresponding files in your repository.
  6. ---
  7. ## Recommended repository structure
  8. ```text
  9. project_root/
  10. ├── input/
  11. │ ├── compound_screening/
  12. │ ├── target_prediction/
  13. │ ├── disease_genes/
  14. │ ├── expression_matrices/
  15. │ ├── candidate_genes/
  16. │ └── docking_outputs/
  17. ├── output/
  18. │ ├── compound_screening/
  19. │ ├── target_prediction/
  20. │ ├── disease_genes/
  21. │ ├── PCA/
  22. │ ├── DEG/
  23. │ ├── enrichment/
  24. │ ├── networks/
  25. │ ├── machine_learning/
  26. │ ├── expression_validation/
  27. │ └── ROC/
  28. └── README.md
  29. ```
  30. ---
  31. ## Input-file conventions
  32. The workflow assumes the following generic input formats.
  33. ### 1. Expression matrix
  34. Rows are genes and columns are samples.
  35. ```text
  36. Gene Sample01_Control Sample02_Control Sample03_Disease
  37. GENE1 5.21 5.34 7.18
  38. GENE2 8.02 7.95 6.11
  39. ```
  40. Sample names should end with `_Control` or `_Disease`.
  41. ### 2. Gene list
  42. One gene symbol per line.
  43. ```text
  44. GENE1
  45. GENE2
  46. GENE3
  47. ```
  48. ### 3. SwissADME output
  49. The SwissADME table should contain columns such as molecular weight, hydrogen-bond donors, hydrogen-bond acceptors, rotatable bonds, LogP values, gastrointestinal absorption, and BBB permeability.
  50. ### 4. SwissTargetPrediction output
  51. Each compound should have a target-prediction CSV file. The target-gene column and probability column should be checked before running the script.
  52. ---
  53. ## R workflow
  54. ```r
  55. # ============================================================
  56. # 0. Setup
  57. # ============================================================
  58. set.seed(12345)
  59. # Install packages manually if needed.
  60. # install.packages(c("dplyr", "ggplot2", "ggpubr", "pheatmap",
  61. # "ggrepel", "ggvenn", "glmnet", "randomForest",
  62. # "e1071", "caret", "pROC", "data.table",
  63. # "tidyverse", "RColorBrewer"))
  64. # if (!requireNamespace("BiocManager", quietly = TRUE)) install.packages("BiocManager")
  65. # BiocManager::install(c("limma", "sva", "clusterProfiler", "org.Hs.eg.db", "enrichplot", "DESeq2"))
  66. suppressPackageStartupMessages({
  67. library(limma)
  68. library(sva)
  69. library(dplyr)
  70. library(ggplot2)
  71. library(ggpubr)
  72. library(pheatmap)
  73. library(ggrepel)
  74. library(ggvenn)
  75. library(clusterProfiler)
  76. library(org.Hs.eg.db)
  77. library(enrichplot)
  78. library(glmnet)
  79. library(randomForest)
  80. library(e1071)
  81. library(caret)
  82. library(pROC)
  83. library(data.table)
  84. library(tidyverse)
  85. })
  86. dir.create("output", showWarnings = FALSE, recursive = TRUE)
  87. # ============================================================
  88. # Helper functions
  89. # ============================================================
  90. read_expression_matrix_simple <- function(file) {
  91. expr <- read.table(
  92. file,
  93. header = TRUE,
  94. sep = "\t",
  95. check.names = FALSE,
  96. row.names = 1,
  97. comment.char = "",
  98. quote = ""
  99. )
  100. expr <- as.matrix(expr)
  101. mode(expr) <- "numeric"
  102. expr <- avereps(expr)
  103. return(expr)
  104. }
  105. extract_group <- function(sample_names) {
  106. group <- sub("^.*_", "", sample_names)
  107. group <- ifelse(
  108. grepl("^Control$", group, ignore.case = TRUE),
  109. "Control",
  110. ifelse(grepl("^Disease$", group, ignore.case = TRUE), "Disease", NA)
  111. )
  112. if (any(is.na(group))) {
  113. stop(
  114. "Sample names must end with '_Control' or '_Disease'. Problematic samples: ",
  115. paste(sample_names[is.na(group)], collapse = ", ")
  116. )
  117. }
  118. factor(group, levels = c("Control", "Disease"))
  119. }
  120. write_vector <- function(x, file) {
  121. write.table(
  122. unique(x),
  123. file = file,
  124. sep = "\t",
  125. quote = FALSE,
  126. row.names = FALSE,
  127. col.names = FALSE
  128. )
  129. }
  130. ensure_dir <- function(path) {
  131. dir.create(path, showWarnings = FALSE, recursive = TRUE)
  132. }
  133. # ============================================================
  134. # 1. Candidate-compound filtering using SwissADME outputs
  135. # ============================================================
  136. filter_swissadme_compounds <- function(
  137. swissadme_file,
  138. output_file,
  139. mw_max = 500,
  140. hbd_max = 5,
  141. hba_max = 10,
  142. rotatable_max = 10,
  143. logp_min = -2,
  144. logp_max = 5,
  145. require_high_gi = TRUE,
  146. require_bbb = TRUE
  147. ) {
  148. adme <- read.csv(
  149. swissadme_file,
  150. header = TRUE,
  151. sep = ",",
  152. check.names = FALSE
  153. )
  154. filtered <- subset(
  155. adme,
  156. MW < mw_max &
  157. `#H-bond donors` < hbd_max &
  158. `#H-bond acceptors` < hba_max &
  159. `#Rotatable bonds` < rotatable_max &
  160. iLOGP > logp_min & iLOGP < logp_max &
  161. XLOGP3 > logp_min & XLOGP3 < logp_max &
  162. `Consensus Log P` > logp_min & `Consensus Log P` < logp_max
  163. )
  164. if (require_high_gi) {
  165. filtered <- subset(filtered, `GI absorption` == "High")
  166. }
  167. if (require_bbb) {
  168. filtered <- subset(filtered, `BBB permeant` == "Yes")
  169. }
  170. write.csv(filtered, output_file, row.names = FALSE)
  171. return(filtered)
  172. }
  173. # Example:
  174. # filtered_compounds <- filter_swissadme_compounds(
  175. # swissadme_file = "input/compound_screening/swissadme_results.csv",
  176. # output_file = "output/compound_screening/filtered_compounds.csv"
  177. # )
  178. # ============================================================
  179. # 2. SwissTargetPrediction target integration
  180. # ============================================================
  181. integrate_predicted_targets <- function(
  182. target_prediction_dir,
  183. filtered_compound_file,
  184. output_file,
  185. probability_cutoff = 0.05,
  186. compound_id_col = 1,
  187. compound_name_col = "Ingredient name",
  188. target_gene_col = 2,
  189. probability_col = "Probability*"
  190. ) {
  191. compound_info <- read.csv(
  192. filtered_compound_file,
  193. header = TRUE,
  194. sep = ",",
  195. check.names = FALSE,
  196. row.names = compound_id_col
  197. )
  198. csv_files <- list.files(
  199. target_prediction_dir,
  200. pattern = "\\.csv$",
  201. full.names = TRUE
  202. )
  203. out <- data.frame()
  204. for (file in csv_files) {
  205. target_table <- read.csv(
  206. file,
  207. header = TRUE,
  208. sep = ",",
  209. check.names = FALSE
  210. )
  211. if (!(probability_col %in% colnames(target_table))) next
  212. target_table <- subset(target_table, target_table[[probability_col]] > probability_cutoff)
  213. if (nrow(target_table) == 0) next
  214. genes <- unlist(strsplit(as.vector(target_table[[target_gene_col]]), " "))
  215. genes <- trimws(genes)
  216. genes <- unique(genes[genes != ""])
  217. compound_id <- tools::file_path_sans_ext(basename(file))
  218. compound_name <- compound_info[compound_id, compound_name_col]
  219. if (length(genes) > 0) {
  220. out <- rbind(
  221. out,
  222. data.frame(
  223. Compound_ID = compound_id,
  224. Compound = compound_name,
  225. Gene = genes,
  226. stringsAsFactors = FALSE
  227. )
  228. )
  229. }
  230. }
  231. out <- unique(out)
  232. write.table(out, output_file, sep = "\t", quote = FALSE, row.names = FALSE)
  233. return(out)
  234. }
  235. # Example:
  236. # predicted_targets <- integrate_predicted_targets(
  237. # target_prediction_dir = "input/target_prediction/",
  238. # filtered_compound_file = "output/compound_screening/filtered_compounds.csv",
  239. # output_file = "output/target_prediction/compound_target_pairs.tsv"
  240. # )
  241. # ============================================================
  242. # 3. Disease-gene integration and Venn plot
  243. # ============================================================
  244. integrate_disease_genes <- function(
  245. disease_gene_dir,
  246. output_union_file,
  247. output_venn_pdf
  248. ) {
  249. files <- list.files(disease_gene_dir, pattern = "\\.txt$", full.names = TRUE)
  250. gene_list <- list()
  251. for (file in files) {
  252. tab <- read.table(file, header = FALSE, sep = "\t", check.names = FALSE)
  253. genes <- unlist(strsplit(as.vector(tab[, 1]), " "))
  254. genes <- trimws(genes)
  255. genes <- unique(genes[genes != ""])
  256. source_name <- tools::file_path_sans_ext(basename(file))
  257. gene_list[[source_name]] <- genes
  258. }
  259. pdf(output_venn_pdf, width = 6, height = 6)
  260. print(
  261. ggvenn(
  262. gene_list,
  263. show_percentage = TRUE,
  264. stroke_color = "white",
  265. stroke_size = 0.5,
  266. fill_color = c("#E41A1C", "#1E90FF", "#FF8C00", "#31A354FF"),
  267. set_name_color = c("#E41A1C", "#1E90FF", "#FF8C00", "#31A354FF"),
  268. set_name_size = 6,
  269. text_size = 4.5
  270. )
  271. )
  272. dev.off()
  273. union_genes <- Reduce(union, gene_list)
  274. write_vector(union_genes, output_union_file)
  275. return(union_genes)
  276. }
  277. # Example:
  278. # disease_genes <- integrate_disease_genes(
  279. # disease_gene_dir = "input/disease_genes/",
  280. # output_union_file = "output/disease_genes/disease_gene_union.tsv",
  281. # output_venn_pdf = "output/disease_genes/disease_gene_venn.pdf"
  282. # )
  283. # ============================================================
  284. # 4. PCA before and after batch correction
  285. # ============================================================
  286. plot_pca <- function(
  287. expression_file,
  288. output_pdf,
  289. title
  290. ) {
  291. expr <- read_expression_matrix_simple(expression_file)
  292. data <- t(expr)
  293. dataset <- gsub("(.*?)\\_.*", "\\1", rownames(data))
  294. pca <- prcomp(data, scale. = FALSE)
  295. pred <- predict(pca)
  296. pca_df <- data.frame(
  297. PC1 = pred[, 1],
  298. PC2 = pred[, 2],
  299. Dataset = dataset
  300. )
  301. pdf(output_pdf, width = 5.5, height = 4.25)
  302. print(
  303. ggscatter(
  304. data = pca_df,
  305. x = "PC1",
  306. y = "PC2",
  307. color = "Dataset",
  308. shape = "Dataset",
  309. ellipse = TRUE,
  310. ellipse.type = "norm",
  311. ellipse.border.remove = FALSE,
  312. ellipse.alpha = 0.1,
  313. size = 2,
  314. main = title,
  315. legend = "right"
  316. ) +
  317. theme(
  318. plot.margin = unit(rep(1.5, 4), "lines"),
  319. plot.title = element_text(hjust = 0.5)
  320. )
  321. )
  322. dev.off()
  323. }
  324. # Example:
  325. # plot_pca("input/expression_matrices/discovery_pre_batch_correction.tsv",
  326. # "output/PCA/PCA_before_batch_correction.pdf",
  327. # "Before batch correction")
  328. # plot_pca("input/expression_matrices/discovery_post_batch_correction.tsv",
  329. # "output/PCA/PCA_after_batch_correction.pdf",
  330. # "After batch correction")
  331. # ============================================================
  332. # 5. Differential-expression analysis for microarray data
  333. # ============================================================
  334. run_limma_deg <- function(
  335. expression_file,
  336. output_dir,
  337. logfc_cutoff = 0.5,
  338. p_cutoff = 0.05,
  339. adj_p_cutoff = 0.05
  340. ) {
  341. ensure_dir(output_dir)
  342. expr <- read_expression_matrix_simple(expression_file)
  343. group <- extract_group(colnames(expr))
  344. expr <- expr[, order(group)]
  345. group <- extract_group(colnames(expr))
  346. design <- model.matrix(~0 + group)
  347. colnames(design) <- levels(group)
  348. fit <- lmFit(expr, design)
  349. contrast_matrix <- makeContrasts(Disease - Control, levels = design)
  350. fit2 <- contrasts.fit(fit, contrast_matrix)
  351. fit2 <- eBayes(fit2)
  352. deg_all <- topTable(fit2, adjust.method = "BH", number = Inf)
  353. deg_all$Gene <- rownames(deg_all)
  354. deg_nominal <- deg_all %>%
  355. filter(P.Value < p_cutoff & abs(logFC) > logfc_cutoff)
  356. deg_fdr <- deg_all %>%
  357. filter(adj.P.Val < adj_p_cutoff & abs(logFC) > logfc_cutoff)
  358. write.table(deg_all, file.path(output_dir, "all_DEG_results.tsv"),
  359. sep = "\t", quote = FALSE, row.names = FALSE)
  360. write.table(deg_nominal, file.path(output_dir, "DEGs_nominalP.tsv"),
  361. sep = "\t", quote = FALSE, row.names = FALSE)
  362. write.table(deg_fdr, file.path(output_dir, "DEGs_FDR.tsv"),
  363. sep = "\t", quote = FALSE, row.names = FALSE)
  364. if (nrow(deg_nominal) > 0) {
  365. write_vector(deg_nominal$Gene, file.path(output_dir, "DEG_gene_list.tsv"))
  366. }
  367. return(list(all = deg_all, nominal = deg_nominal, fdr = deg_fdr))
  368. }
  369. # Example:
  370. # deg_results <- run_limma_deg(
  371. # expression_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  372. # output_dir = "output/DEG/"
  373. # )
  374. # ============================================================
  375. # 6. GO enrichment analysis
  376. # ============================================================
  377. run_go_enrichment <- function(
  378. gene_file,
  379. output_dir,
  380. pvalue_cutoff = 0.05,
  381. padj_cutoff = 0.05
  382. ) {
  383. ensure_dir(output_dir)
  384. genes <- read.table(gene_file, header = FALSE, sep = "\t", check.names = FALSE)[, 1]
  385. genes <- unique(genes)
  386. entrez <- mget(genes, org.Hs.egSYMBOL2EG, ifnotfound = NA)
  387. entrez <- as.character(entrez)
  388. entrez <- entrez[entrez != "NA"]
  389. ego <- enrichGO(
  390. gene = entrez,
  391. OrgDb = org.Hs.eg.db,
  392. pvalueCutoff = 1,
  393. qvalueCutoff = 1,
  394. ont = "all",
  395. readable = TRUE
  396. )
  397. go_df <- as.data.frame(ego)
  398. go_sig <- go_df %>%
  399. filter(pvalue < pvalue_cutoff & p.adjust < padj_cutoff)
  400. write.table(go_sig, file.path(output_dir, "GO_enrichment_results.tsv"),
  401. sep = "\t", quote = FALSE, row.names = FALSE)
  402. pdf(file.path(output_dir, "GO_barplot.pdf"), width = 8.5, height = 7)
  403. print(
  404. barplot(
  405. ego,
  406. drop = TRUE,
  407. showCategory = 10,
  408. label_format = 100,
  409. split = "ONTOLOGY",
  410. color = "p.adjust"
  411. ) +
  412. facet_grid(ONTOLOGY ~ ., scale = "free")
  413. )
  414. dev.off()
  415. return(go_sig)
  416. }
  417. # Example:
  418. # go_results <- run_go_enrichment(
  419. # gene_file = "input/candidate_genes/overlapping_genes.tsv",
  420. # output_dir = "output/enrichment/GO/"
  421. # )
  422. # ============================================================
  423. # 7. KEGG enrichment analysis
  424. # ============================================================
  425. run_kegg_enrichment <- function(
  426. gene_file,
  427. output_dir,
  428. pvalue_cutoff = 0.05,
  429. padj_cutoff = 0.05,
  430. show_n = 20
  431. ) {
  432. ensure_dir(output_dir)
  433. genes <- read.table(gene_file, header = FALSE, sep = "\t", check.names = FALSE)[, 1]
  434. genes <- unique(genes)
  435. entrez <- mget(genes, org.Hs.egSYMBOL2EG, ifnotfound = NA)
  436. entrez <- as.character(entrez)
  437. mapping <- data.frame(Gene = genes, EntrezID = entrez, stringsAsFactors = FALSE)
  438. entrez <- entrez[entrez != "NA"]
  439. ekegg <- enrichKEGG(
  440. gene = entrez,
  441. organism = "hsa",
  442. pvalueCutoff = 1,
  443. qvalueCutoff = 1
  444. )
  445. kegg_df <- as.data.frame(ekegg)
  446. if (nrow(kegg_df) > 0) {
  447. kegg_df$geneID <- as.character(sapply(kegg_df$geneID, function(x) {
  448. paste(mapping$Gene[match(strsplit(x, "/")[[1]], as.character(mapping$EntrezID))],
  449. collapse = "/")
  450. }))
  451. }
  452. kegg_sig <- kegg_df %>%
  453. filter(pvalue < pvalue_cutoff & p.adjust < padj_cutoff) %>%
  454. filter(category != "Human Diseases") %>%
  455. na.omit()
  456. write.table(kegg_sig, file.path(output_dir, "KEGG_enrichment_results.tsv"),
  457. sep = "\t", quote = FALSE, row.names = FALSE)
  458. if (nrow(kegg_sig) > 0) {
  459. show_kegg <- kegg_sig[seq_len(min(show_n, nrow(kegg_sig))), ]
  460. show_kegg$Pathway <- factor(show_kegg$Description, levels = rev(show_kegg$Description))
  461. p <- ggplot(show_kegg, aes(x = Count, y = Pathway, fill = p.adjust)) +
  462. geom_bar(stat = "identity", width = 0.75) +
  463. scale_fill_distiller(palette = "Spectral", direction = 1) +
  464. labs(x = "Gene count", y = "", title = "Enriched KEGG pathways") +
  465. theme_bw() +
  466. theme(
  467. plot.title = element_text(size = 12, hjust = 0.5, face = "bold"),
  468. axis.title = element_text(size = 11),
  469. axis.text = element_text(size = 10),
  470. legend.title = element_text(size = 11),
  471. legend.text = element_text(size = 10)
  472. )
  473. pdf(file.path(output_dir, "KEGG_barplot.pdf"), width = 7, height = 5.5)
  474. print(p)
  475. dev.off()
  476. }
  477. return(kegg_sig)
  478. }
  479. # Example:
  480. # kegg_results <- run_kegg_enrichment(
  481. # gene_file = "input/candidate_genes/overlapping_genes.tsv",
  482. # output_dir = "output/enrichment/KEGG/"
  483. # )
  484. # ============================================================
  485. # 8. Network-file construction for Cytoscape
  486. # ============================================================
  487. build_compound_target_pathway_network <- function(
  488. compound_target_file,
  489. kegg_file,
  490. output_dir,
  491. top_kegg_n = 10
  492. ) {
  493. ensure_dir(output_dir)
  494. compound_target <- read.table(
  495. compound_target_file,
  496. header = TRUE,
  497. sep = "\t",
  498. check.names = FALSE,
  499. comment.char = "",
  500. quote = ""
  501. )
  502. kegg <- read.table(
  503. kegg_file,
  504. header = TRUE,
  505. sep = "\t",
  506. check.names = FALSE,
  507. comment.char = "",
  508. quote = ""
  509. )
  510. kegg_top <- kegg[order(kegg$p.adjust, kegg$pvalue), ]
  511. kegg_top <- head(kegg_top, top_kegg_n)
  512. drug_name <- unique(compound_target$Drug)[1]
  513. disease_name <- unique(compound_target$Disease)[1]
  514. compound_list <- unique(compound_target$Compound)
  515. gene_list <- unique(compound_target$Gene)
  516. pathway_list <- unique(kegg_top$Description)
  517. network <- data.frame()
  518. for (compound in compound_list) {
  519. network <- rbind(
  520. network,
  521. data.frame(Node1 = drug_name, Node2 = compound, Interaction = "Drug-Compound")
  522. )
  523. genes <- unique(compound_target$Gene[compound_target$Compound == compound])
  524. genes <- genes[!is.na(genes) & genes != ""]
  525. if (length(genes) > 0) {
  526. network <- rbind(
  527. network,
  528. data.frame(Node1 = compound, Node2 = genes, Interaction = "Compound-Target")
  529. )
  530. }
  531. }
  532. for (i in seq_len(nrow(kegg_top))) {
  533. pathway <- kegg_top$Description[i]
  534. network <- rbind(
  535. network,
  536. data.frame(Node1 = disease_name, Node2 = pathway, Interaction = "Disease-Pathway")
  537. )
  538. genes <- unlist(strsplit(as.vector(kegg_top$geneID[i]), "/"))
  539. genes <- trimws(unique(genes))
  540. genes <- intersect(genes, gene_list)
  541. if (length(genes) > 0) {
  542. network <- rbind(
  543. network,
  544. data.frame(Node1 = pathway, Node2 = genes, Interaction = "Pathway-Target")
  545. )
  546. }
  547. }
  548. network <- unique(network)
  549. all_nodes <- unique(c(network$Node1, network$Node2))
  550. node_type <- ifelse(
  551. all_nodes == drug_name, "Drug",
  552. ifelse(
  553. all_nodes == disease_name, "Disease",
  554. ifelse(
  555. all_nodes %in% compound_list, "Compound",
  556. ifelse(
  557. all_nodes %in% pathway_list, "Pathway",
  558. ifelse(all_nodes %in% gene_list, "Target", "Other")
  559. )
  560. )
  561. )
  562. )
  563. nodes <- data.frame(Node = all_nodes, Type = node_type)
  564. write.table(network, file.path(output_dir, "network_edges.tsv"),
  565. sep = "\t", quote = FALSE, row.names = FALSE)
  566. write.table(nodes, file.path(output_dir, "network_nodes.tsv"),
  567. sep = "\t", quote = FALSE, row.names = FALSE)
  568. write_vector(gene_list, file.path(output_dir, "network_gene_list.tsv"))
  569. write_vector(compound_list, file.path(output_dir, "network_compound_list.tsv"))
  570. write_vector(pathway_list, file.path(output_dir, "network_pathway_list.tsv"))
  571. return(list(edges = network, nodes = nodes))
  572. }
  573. # Example:
  574. # network_files <- build_compound_target_pathway_network(
  575. # compound_target_file = "input/network/compound_target_info.tsv",
  576. # kegg_file = "output/enrichment/KEGG/KEGG_enrichment_results.tsv",
  577. # output_dir = "output/networks/"
  578. # )
  579. # ============================================================
  580. # 9. LASSO feature selection
  581. # ============================================================
  582. run_lasso_feature_selection <- function(
  583. expression_file,
  584. candidate_gene_file,
  585. output_dir,
  586. nfolds = 10
  587. ) {
  588. ensure_dir(output_dir)
  589. expr <- read_expression_matrix_simple(expression_file)
  590. candidate_genes <- read.table(candidate_gene_file, header = FALSE, sep = "\t")[, 1]
  591. candidate_genes <- intersect(unique(candidate_genes), rownames(expr))
  592. expr <- expr[candidate_genes, , drop = FALSE]
  593. x <- as.matrix(t(expr))
  594. y <- extract_group(rownames(x))
  595. fit <- glmnet(x, y, family = "binomial", alpha = 1)
  596. cvfit <- cv.glmnet(
  597. x,
  598. y,
  599. family = "binomial",
  600. alpha = 1,
  601. type.measure = "deviance",
  602. nfolds = nfolds
  603. )
  604. pdf(file.path(output_dir, "LASSO_coefficient_path.pdf"), width = 6, height = 5.5)
  605. plot(fit)
  606. dev.off()
  607. pdf(file.path(output_dir, "LASSO_cross_validation.pdf"), width = 6, height = 5.5)
  608. plot(cvfit)
  609. dev.off()
  610. coef_min <- coef(cvfit, s = "lambda.min")
  611. selected <- rownames(coef_min)[which(as.numeric(coef_min) != 0)]
  612. selected <- setdiff(selected, "(Intercept)")
  613. write_vector(selected, file.path(output_dir, "LASSO_selected_genes.tsv"))
  614. return(selected)
  615. }
  616. # Example:
  617. # lasso_genes <- run_lasso_feature_selection(
  618. # expression_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  619. # candidate_gene_file = "input/candidate_genes/overlapping_genes.tsv",
  620. # output_dir = "output/machine_learning/LASSO/"
  621. # )
  622. # ============================================================
  623. # 10. Random-forest feature selection
  624. # ============================================================
  625. run_random_forest_feature_selection <- function(
  626. expression_file,
  627. candidate_gene_file,
  628. output_dir,
  629. repeat_times = 1000,
  630. ntree = 500,
  631. top_n = 10,
  632. frequency_cutoff = 0.5
  633. ) {
  634. ensure_dir(output_dir)
  635. expr <- read_expression_matrix_simple(expression_file)
  636. candidate_genes <- read.table(candidate_gene_file, header = FALSE, sep = "\t")[, 1]
  637. candidate_genes <- intersect(unique(candidate_genes), rownames(expr))
  638. expr <- expr[candidate_genes, , drop = FALSE]
  639. data <- as.data.frame(t(expr))
  640. group <- extract_group(rownames(data))
  641. selected_list <- list()
  642. for (i in seq_len(repeat_times)) {
  643. rf <- randomForest(as.factor(group) ~ ., data = data, ntree = ntree)
  644. imp <- importance(rf)
  645. top_genes <- rownames(imp)[order(imp[, 1], decreasing = TRUE)[seq_len(min(top_n, nrow(imp)))]]
  646. selected_list[[i]] <- top_genes
  647. }
  648. gene_frequency <- sort(table(unlist(selected_list)), decreasing = TRUE)
  649. stable_genes <- names(gene_frequency[gene_frequency >= repeat_times * frequency_cutoff])
  650. write.table(
  651. data.frame(Gene = names(gene_frequency), Frequency = as.numeric(gene_frequency)),
  652. file.path(output_dir, "RF_gene_selection_frequency.tsv"),
  653. sep = "\t",
  654. quote = FALSE,
  655. row.names = FALSE
  656. )
  657. write_vector(stable_genes, file.path(output_dir, "RF_stable_genes.tsv"))
  658. return(stable_genes)
  659. }
  660. # Example:
  661. # rf_genes <- run_random_forest_feature_selection(
  662. # expression_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  663. # candidate_gene_file = "input/candidate_genes/overlapping_genes.tsv",
  664. # output_dir = "output/machine_learning/RF/",
  665. # top_n = 10
  666. # )
  667. # ============================================================
  668. # 11. SVM-RFE feature selection
  669. # ============================================================
  670. run_svm_rfe_feature_selection <- function(
  671. expression_file,
  672. candidate_gene_file,
  673. output_dir,
  674. cv_number = 10,
  675. cv_repeats = 5,
  676. acc_ratio = 0.998,
  677. min_gene_n = 4,
  678. max_gene_n = 10
  679. ) {
  680. ensure_dir(output_dir)
  681. expr <- read_expression_matrix_simple(expression_file)
  682. candidate_genes <- read.table(candidate_gene_file, header = FALSE, sep = "\t")[, 1]
  683. candidate_genes <- intersect(unique(candidate_genes), rownames(expr))
  684. expr <- expr[candidate_genes, , drop = FALSE]
  685. data <- as.data.frame(t(expr))
  686. group <- extract_group(rownames(data))
  687. data$group <- group
  688. gene_var <- apply(data[, candidate_genes, drop = FALSE], 2, var)
  689. candidate_genes <- names(gene_var[gene_var > 0])
  690. data <- data[, c(candidate_genes, "group")]
  691. x <- data[, candidate_genes, drop = FALSE]
  692. y <- data$group
  693. svm_fit <- svm(x = x, y = y, kernel = "linear", scale = TRUE)
  694. w <- t(svm_fit$coefs) %*% svm_fit$SV
  695. gene_rank <- data.frame(
  696. Gene = colnames(x),
  697. Weight = as.numeric(w),
  698. AbsWeight = abs(as.numeric(w))
  699. )
  700. gene_rank <- gene_rank[order(gene_rank$AbsWeight, decreasing = TRUE), ]
  701. write.table(gene_rank, file.path(output_dir, "SVM_gene_ranking.tsv"),
  702. sep = "\t", quote = FALSE, row.names = FALSE)
  703. ctrl <- trainControl(
  704. method = "repeatedcv",
  705. number = cv_number,
  706. repeats = cv_repeats,
  707. classProbs = TRUE,
  708. summaryFunction = defaultSummary,
  709. savePredictions = "final"
  710. )
  711. svm_result <- data.frame()
  712. for (i in seq_len(nrow(gene_rank))) {
  713. use_genes <- gene_rank$Gene[seq_len(i)]
  714. tmp_data <- data[, c(use_genes, "group")]
  715. fit <- train(
  716. group ~ .,
  717. data = tmp_data,
  718. method = "svmLinear",
  719. metric = "Accuracy",
  720. trControl = ctrl,
  721. preProcess = c("center", "scale")
  722. )
  723. acc <- max(fit$results$Accuracy, na.rm = TRUE)
  724. svm_result <- rbind(
  725. svm_result,
  726. data.frame(GeneNumber = i, Accuracy = acc, Error = 1 - acc)
  727. )
  728. }
  729. write.table(svm_result, file.path(output_dir, "SVM_RFE_performance.tsv"),
  730. sep = "\t", quote = FALSE, row.names = FALSE)
  731. best_acc <- max(svm_result$Accuracy, na.rm = TRUE)
  732. threshold <- best_acc * acc_ratio
  733. max_gene_n <- min(max_gene_n, nrow(gene_rank))
  734. candidate_n <- svm_result$GeneNumber[
  735. svm_result$Accuracy >= threshold &
  736. svm_result$GeneNumber >= min_gene_n &
  737. svm_result$GeneNumber <= max_gene_n
  738. ]
  739. if (length(candidate_n) == 0) {
  740. tmp <- svm_result[
  741. svm_result$GeneNumber >= min_gene_n &
  742. svm_result$GeneNumber <= max_gene_n, ]
  743. best_gene_n <- tmp$GeneNumber[which.max(tmp$Accuracy)]
  744. } else {
  745. best_gene_n <- min(candidate_n)
  746. }
  747. selected <- gene_rank$Gene[seq_len(best_gene_n)]
  748. write_vector(selected, file.path(output_dir, "SVM_RFE_selected_genes.tsv"))
  749. pdf(file.path(output_dir, "SVM_RFE_accuracy.pdf"), width = 7, height = 6)
  750. print(
  751. ggplot(svm_result, aes(x = GeneNumber, y = Accuracy)) +
  752. geom_line(linewidth = 1.2, color = "#50C878") +
  753. geom_point(size = 2.5, color = "#50C878") +
  754. geom_hline(yintercept = threshold, linetype = "dotted", color = "gray40") +
  755. geom_vline(xintercept = best_gene_n, linetype = "dashed", color = "red") +
  756. annotate("text", x = best_gene_n,
  757. y = svm_result$Accuracy[svm_result$GeneNumber == best_gene_n],
  758. label = paste0("n=", best_gene_n),
  759. color = "red",
  760. fontface = "bold",
  761. size = 5,
  762. vjust = -1) +
  763. theme_bw() +
  764. labs(x = "Number of features", y = "Cross-validation accuracy",
  765. title = "SVM-RFE accuracy")
  766. )
  767. dev.off()
  768. return(selected)
  769. }
  770. # Example:
  771. # svm_genes <- run_svm_rfe_feature_selection(
  772. # expression_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  773. # candidate_gene_file = "input/candidate_genes/overlapping_genes.tsv",
  774. # output_dir = "output/machine_learning/SVM_RFE/"
  775. # )
  776. # ============================================================
  777. # 12. Hub-gene expression validation
  778. # ============================================================
  779. plot_hub_gene_expression <- function(
  780. discovery_expr_file,
  781. validation_expr_file,
  782. hub_gene_file,
  783. output_pdf
  784. ) {
  785. discovery_expr <- read_expression_matrix_simple(discovery_expr_file)
  786. validation_expr <- read_expression_matrix_simple(validation_expr_file)
  787. hub_genes <- read.table(hub_gene_file, header = FALSE, sep = "\t")[, 1]
  788. hub_genes <- unique(hub_genes)
  789. discovery_expr <- discovery_expr[intersect(hub_genes, rownames(discovery_expr)), , drop = FALSE]
  790. validation_expr <- validation_expr[intersect(hub_genes, rownames(validation_expr)), , drop = FALSE]
  791. reshape_expression <- function(expr, dataset_name) {
  792. df <- as.data.frame(expr)
  793. df$Gene <- rownames(df)
  794. df_long <- df %>%
  795. pivot_longer(-Gene, names_to = "Sample", values_to = "Expression") %>%
  796. mutate(
  797. Group = case_when(
  798. grepl("_Control$", Sample) ~ "Control",
  799. grepl("_Disease$", Sample) ~ "Disease",
  800. TRUE ~ NA_character_
  801. ),
  802. Dataset = dataset_name
  803. ) %>%
  804. filter(!is.na(Group))
  805. df_long
  806. }
  807. discovery_long <- reshape_expression(discovery_expr, "Discovery")
  808. validation_long <- reshape_expression(validation_expr, "Validation")
  809. all_data <- bind_rows(discovery_long, validation_long)
  810. all_data$Group <- factor(all_data$Group, levels = c("Control", "Disease"))
  811. all_data$Dataset <- factor(all_data$Dataset, levels = c("Discovery", "Validation"))
  812. p <- ggboxplot(
  813. all_data,
  814. x = "Dataset",
  815. y = "Expression",
  816. color = "Group",
  817. fill = "Group",
  818. add = "jitter",
  819. facet.by = "Gene",
  820. short.panel.labs = TRUE,
  821. nrow = 1,
  822. xlab = "",
  823. ylab = "Expression",
  824. legend = "top"
  825. ) +
  826. stat_compare_means(
  827. aes(group = Group),
  828. method = "t.test",
  829. label = "p.signif",
  830. label.y.npc = "top",
  831. hide.ns = TRUE
  832. ) +
  833. theme_bw(base_size = 12) +
  834. theme(
  835. strip.text = element_text(face = "bold", size = 12),
  836. panel.grid = element_blank(),
  837. axis.text.x = element_text(angle = 45, hjust = 1),
  838. legend.title = element_blank()
  839. )
  840. pdf(output_pdf, width = 12, height = 4.5)
  841. print(p)
  842. dev.off()
  843. return(all_data)
  844. }
  845. # Example:
  846. # hub_expression_data <- plot_hub_gene_expression(
  847. # discovery_expr_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  848. # validation_expr_file = "input/expression_matrices/validation_expression.tsv",
  849. # hub_gene_file = "input/candidate_genes/final_hub_genes.tsv",
  850. # output_pdf = "output/expression_validation/hub_gene_expression.pdf"
  851. # )
  852. # ============================================================
  853. # 13. ROC analysis for single genes and multigene model
  854. # ============================================================
  855. run_roc_analysis <- function(
  856. discovery_expr_file,
  857. validation_expr_file,
  858. hub_gene_file,
  859. output_dir,
  860. k = 5
  861. ) {
  862. ensure_dir(output_dir)
  863. discovery_expr <- read_expression_matrix_simple(discovery_expr_file)
  864. validation_expr <- read_expression_matrix_simple(validation_expr_file)
  865. discovery_group <- extract_group(colnames(discovery_expr))
  866. validation_group <- extract_group(colnames(validation_expr))
  867. hub_genes <- read.table(hub_gene_file, header = FALSE, sep = "\t")[, 1]
  868. hub_genes <- unique(hub_genes)
  869. hub_genes <- intersect(hub_genes, rownames(discovery_expr))
  870. hub_genes <- intersect(hub_genes, rownames(validation_expr))
  871. if (length(hub_genes) < 1) {
  872. stop("No hub genes were found in both discovery and validation datasets.")
  873. }
  874. discovery_df <- as.data.frame(t(discovery_expr[hub_genes, , drop = FALSE]))
  875. validation_df <- as.data.frame(t(validation_expr[hub_genes, , drop = FALSE]))
  876. discovery_df$group <- discovery_group
  877. validation_df$group <- validation_group
  878. # Single-gene ROC in discovery and validation datasets
  879. single_roc_summary <- data.frame()
  880. for (dataset_name in c("Discovery", "Validation")) {
  881. if (dataset_name == "Discovery") {
  882. df <- discovery_df
  883. group <- discovery_group
  884. } else {
  885. df <- validation_df
  886. group <- validation_group
  887. }
  888. pdf(file.path(output_dir, paste0("single_gene_ROC_", dataset_name, ".pdf")),
  889. width = 6, height = 5)
  890. auc_text <- c()
  891. colors <- rainbow(length(hub_genes))
  892. for (i in seq_along(hub_genes)) {
  893. gene <- hub_genes[i]
  894. roc_obj <- roc(
  895. response = df$group,
  896. predictor = as.numeric(df[[gene]]),
  897. levels = c("Control", "Disease"),
  898. direction = "auto",
  899. ci = TRUE
  900. )
  901. ci_obj <- ci.auc(roc_obj)
  902. single_roc_summary <- rbind(
  903. single_roc_summary,
  904. data.frame(
  905. Dataset = dataset_name,
  906. Gene = gene,
  907. AUC = as.numeric(auc(roc_obj)),
  908. CI_low = as.numeric(ci_obj[1]),
  909. CI_high = as.numeric(ci_obj[3])
  910. )
  911. )
  912. if (i == 1) {
  913. plot(roc_obj, col = colors[i], lwd = 3, legacy.axes = TRUE,
  914. main = paste0("Single-gene ROC curves in ", tolower(dataset_name), " dataset"))
  915. } else {
  916. plot(roc_obj, col = colors[i], lwd = 3, legacy.axes = TRUE, add = TRUE)
  917. }
  918. auc_text <- c(auc_text, paste0(gene, ", AUC=", sprintf("%.3f", auc(roc_obj))))
  919. }
  920. legend("bottomright", legend = auc_text, col = colors, lwd = 3, bty = "n", cex = 0.8)
  921. dev.off()
  922. }
  923. write.csv(single_roc_summary,
  924. file.path(output_dir, "single_gene_ROC_summary.csv"),
  925. row.names = FALSE)
  926. # Five-fold cross-validation in discovery dataset
  927. x_cv <- discovery_df[, hub_genes, drop = FALSE]
  928. x_cv_scaled <- as.data.frame(scale(x_cv))
  929. colnames(x_cv_scaled) <- make.names(colnames(x_cv_scaled))
  930. cv_df <- x_cv_scaled
  931. cv_df$group <- discovery_df$group
  932. fold_id <- sample(rep(seq_len(k), length.out = nrow(cv_df)))
  933. cv_pred <- rep(NA, nrow(cv_df))
  934. for (fold in seq_len(k)) {
  935. train_idx <- which(fold_id != fold)
  936. test_idx <- which(fold_id == fold)
  937. train_fold <- cv_df[train_idx, , drop = FALSE]
  938. test_fold <- cv_df[test_idx, , drop = FALSE]
  939. formula_cv <- as.formula(
  940. paste("group ~", paste(colnames(x_cv_scaled), collapse = " + "))
  941. )
  942. fit <- glm(formula_cv, data = train_fold, family = binomial(link = "logit"))
  943. cv_pred[test_idx] <- predict(fit, newdata = test_fold, type = "response")
  944. }
  945. roc_cv <- roc(
  946. response = cv_df$group,
  947. predictor = cv_pred,
  948. levels = c("Control", "Disease"),
  949. direction = "auto",
  950. ci = TRUE
  951. )
  952. cv_ci <- ci.auc(roc_cv)
  953. pdf(file.path(output_dir, "multigene_model_ROC_discovery_5foldCV.pdf"),
  954. width = 5.5, height = 5)
  955. plot(roc_cv, print.auc = TRUE, col = "red", legacy.axes = TRUE,
  956. main = "Five-fold CV ROC in discovery dataset", lwd = 3)
  957. text(0.45, 0.35,
  958. paste0("95% CI: ", sprintf("%.3f", cv_ci[1]), "-", sprintf("%.3f", cv_ci[3])),
  959. col = "red")
  960. dev.off()
  961. # Train discovery model and apply to external validation dataset
  962. x_train <- discovery_df[, hub_genes, drop = FALSE]
  963. x_test <- validation_df[, hub_genes, drop = FALSE]
  964. train_mean <- apply(x_train, 2, mean, na.rm = TRUE)
  965. train_sd <- apply(x_train, 2, sd, na.rm = TRUE)
  966. x_train_scaled <- as.data.frame(scale(x_train, center = train_mean, scale = train_sd))
  967. x_test_scaled <- as.data.frame(scale(x_test, center = train_mean, scale = train_sd))
  968. colnames(x_train_scaled) <- make.names(colnames(x_train_scaled))
  969. colnames(x_test_scaled) <- make.names(colnames(x_test_scaled))
  970. model_df <- x_train_scaled
  971. model_df$group <- discovery_df$group
  972. formula_model <- as.formula(
  973. paste("group ~", paste(colnames(x_train_scaled), collapse = " + "))
  974. )
  975. fit_model <- glm(formula_model, data = model_df, family = binomial(link = "logit"))
  976. validation_pred <- predict(fit_model, newdata = x_test_scaled, type = "response")
  977. roc_validation <- roc(
  978. response = validation_df$group,
  979. predictor = validation_pred,
  980. levels = c("Control", "Disease"),
  981. direction = "auto",
  982. ci = TRUE
  983. )
  984. validation_ci <- ci.auc(roc_validation)
  985. pdf(file.path(output_dir, "multigene_model_ROC_external_validation.pdf"),
  986. width = 5.5, height = 5)
  987. plot(roc_validation, print.auc = TRUE, col = "red", legacy.axes = TRUE,
  988. main = "External validation ROC of multigene model", lwd = 3)
  989. text(0.45, 0.35,
  990. paste0("95% CI: ", sprintf("%.3f", validation_ci[1]), "-", sprintf("%.3f", validation_ci[3])),
  991. col = "red")
  992. dev.off()
  993. model_summary <- data.frame(
  994. Model = c("Multigene model, five-fold CV in discovery dataset",
  995. "Multigene model, external validation"),
  996. AUC = c(as.numeric(auc(roc_cv)), as.numeric(auc(roc_validation))),
  997. CI_low = c(as.numeric(cv_ci[1]), as.numeric(validation_ci[1])),
  998. CI_high = c(as.numeric(cv_ci[3]), as.numeric(validation_ci[3]))
  999. )
  1000. write.csv(model_summary,
  1001. file.path(output_dir, "multigene_ROC_summary.csv"),
  1002. row.names = FALSE)
  1003. return(list(single_gene = single_roc_summary, multigene = model_summary))
  1004. }
  1005. # Example:
  1006. # roc_results <- run_roc_analysis(
  1007. # discovery_expr_file = "input/expression_matrices/discovery_post_batch_correction.tsv",
  1008. # validation_expr_file = "input/expression_matrices/validation_expression.tsv",
  1009. # hub_gene_file = "input/candidate_genes/final_hub_genes.tsv",
  1010. # output_dir = "output/ROC/"
  1011. # )
  1012. # ============================================================
  1013. # 14. Session information
  1014. # ============================================================
  1015. # Save the R session information for reproducibility.
  1016. # writeLines(capture.output(sessionInfo()), "output/sessionInfo.txt")
  1017. ```
  1018. ---
  1019. ## Notes for reuse
  1020. 1. Replace all placeholder filenames with the files in your repository.
  1021. 2. Keep input sample names ending with `_Control` or `_Disease`.
  1022. 3. The microarray differential-expression workflow uses `limma` and reports Benjamini-Hochberg adjusted *P* values.
  1023. 4. The ROC workflow uses `pROC::roc()` and `pROC::ci.auc()` to calculate AUC values and confidence intervals.
  1024. 5. External validation datasets are used only for validation and are not used for feature selection or model fitting.
  1025. 6. The code is intended for reproducibility of the analysis workflow and should be accompanied by processed input matrices, sample metadata, and output tables.
  1026. ---
  1027. ## Suggested citation statement for the manuscript repository
  1028. ```text
  1029. All author-generated R code used for data processing, differential-expression analysis, enrichment analysis, machine-learning feature selection, ROC analysis and figure generation is provided in this repository. Local paths and non-public filenames have been replaced with generic placeholders to facilitate reuse.
  1030. ```

README.md, under CC-BY-4.0 · at the source

Overview

Authors: Yuxi Xie1, Chong-Teik Lim2, Xin-Jieh Lam3, Pike-See Cheah4,5, King-Hwa Ling2,5,6,7, Tan Huang8
  1. Department of Clinical Nutrition, The Second Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
  2. Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
  3. Department of Molecular Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
  4. Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
  5. Malaysian Research Institute on Ageing (MyAgeing®), Universiti Putra Malaysia, Serdang, Selangor, Malaysia
  6. M Kandiah Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman Cheras, Kajang, Selangor, Malaysia
  7. Fakultas Kedokteran, Universitas Pembangunan Nasional “Veteran” Jakarta, Jakarta, Indonesia
  8. Department of Neurosurgery, The Second Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
Journal: PloS one, volume 21, issue 7, article e0354882
Dates: received 22 April 2026; accepted 12 July 2026; published online 31 July 2026
Type: Research article · Language: English
License: CC BY
Identifiers: DOI 10.1371/journal.pone.0354882 · PMID 42536688 · PMCID PMC13426974 · OpenAlex W7171985819
Open access: gold, a free copy (OpenAlex)
Status: code verified
Categories: genetics / omics (modality), human (organism), other condition (population), cellular / molecular (subfield)
Methods: Statistics, Smoothing, state filtering, decompositions, Machine learning
MeSH: Centella*, Molecular Docking Simulation*, Network Pharmacology*, Neurodegenerative Diseases*, Transcriptome*, Triterpenes*, Gene Expression Profiling, Humans (* major topic)
Topic: Medicinal Plants and Neuroprotection (Complementary and alternative medicine, Medicine), according to OpenAlex
Citations: not cited yet (Europe PMC); 68 references in the paper

Abstract

Background: Neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD), are progressive disorders with limited therapeutic options. Centella asiatica (C. asiatica), a medicinal and edible plant, has been reported to exert neuroprotective and anti-neuroinflammatory properties. Yet, the mechanisms underlying its effects against neurodegenerative diseases remain largely unclear.

Methods: We employed an integrative strategy combining network pharmacology, transcriptomic analyses, machine learning and molecular docking to prioritize disease-associated molecular networks and candidate compound–target relationships in AD, PD and HD.

Results: Sixteen candidate constituents of C. asiatica met the predefined drug-likeness, gastrointestinal absorption and blood–brain barrier permeability criteria, yielding 370 unique predicted targets. Disease-gene mining identified 983 AD-associated genes, 1,103 PD-associated genes, and 3,316 HD-associated genes. Integration of compound targets, disease-associated genes, and transcriptomic profiles prioritized five hub genes in PD (CCKAR, MAPK8, PSEN2, SLC6A3, and TH), four in AD (APP, PGK1, PIK3CA, and TTR), and four in HD (CHRND, HSP90AA1, PRKCQ, and TH). Enrichment analyses highlighted disease-relevant processes involving neurotransmitter signalling, cAMP and calcium pathways, MAPK-related responses and inflammatory regulation. ROC analyses provided additional support for the discriminatory performance of the prioritized genes in independent datasets, whereas molecular docking identified favourable predicted Vina docking scores and structurally plausible interactions between selected compounds and hub targets.

Conclusion: This integrative computational analysis prioritizes candidate C. asiatica constituents, putative disease-associated targets, and molecular pathways in AD, PD, and HD. The findings provide a foundation for subsequent biochemical, cellular, and in vivo validation.

Reproduced under the paper's license (CC BY), from the paper cited above.

Repository

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Zenodo 20779507

License: CC-BY-4.0
State: the link answers, verified on 27 September 2026
Evidence: files inventoried
Size: 1 file
Software Heritage: not checked
Found in: “Data Availability”
Not found: README, license file, CITATION.cff, environment file, tests, continuous integration, documentation
Availability: 1 check, the latest on 27 September 2026: the link answers (HTTP 200)
  • 27 September 2026: the link answers (HTTP 200)
1 file

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Data

Datasets cited

Data Availability

No new experimental raw data were generated in this study. The raw transcriptomic datasets analyzed in this study are publicly available from the Gene Expression Omnibus under accession numbers GSE20163, GSE20164, GSE26927, GSE7621, GSE5281, GSE36980, GSE118553, GSE64810 and GSE33000. Processed gene-expression matrices, differential-expression results, and anonymized analysis code generated in this study have been deposited in Zenodo and are available at https://doi.org/10.5281/zenodo.20779507.

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Versions

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Version 1, 27 September 2026: the first record

Recorded: type, language, journal, volume, issue, pages, dates, 6 authors, 8 MeSH terms, 68 references.

Cite

This paper

Xie, Y., Lim, C.-T., Lam, X.-J., Cheah, P.-S., Ling, K.-H., & Huang, T. (2026). Integrative network pharmacology, transcriptomics, and molecular docking identify candidate Centella asiatica constituents and targets in neurodegenerative diseases. PloS one, 21(7), e0354882. https://doi.org/10.1371/journal.pone.0354882

BibTeX

@article{xie2026integrative,
author = {Xie, Yuxi and Lim, Chong-Teik and Lam, Xin-Jieh and Cheah, Pike-See and Ling, King-Hwa and Huang, Tan},
title = {{Integrative network pharmacology, transcriptomics, and molecular docking identify candidate Centella asiatica constituents and targets in neurodegenerative diseases}},
journal = {PloS one},
year = {2026},
month = jul,
volume = {21},
number = {7},
pages = {e0354882},
publisher = {PLOS},
issn = {1932-6203},
doi = {10.1371/journal.pone.0354882},
url = {https://doi.org/10.1371/journal.pone.0354882},
pmid = {42536688},
pmcid = {PMC13426974}
}

RIS

TY - JOUR
AU - Xie, Yuxi
AU - Lim, Chong-Teik
AU - Lam, Xin-Jieh
AU - Cheah, Pike-See
AU - Ling, King-Hwa
AU - Huang, Tan
TI - Integrative network pharmacology, transcriptomics, and molecular docking identify candidate Centella asiatica constituents and targets in neurodegenerative diseases
T2 - PloS one
J2 - PLoS One
PY - 2026
DA - 2026/07/31
VL - 21
IS - 7
SP - e0354882
SN - 1932-6203
PB - PLOS
DO - 10.1371/journal.pone.0354882
UR - https://doi.org/10.1371/journal.pone.0354882
LA - en
ER -

CSL-JSON

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