Human carboxylesterase 2A (hCES2A) plays pivotal roles in prodrug activation and hydrolytic metabolism of ester-bearing chemicals. Targeted inhibition of intestinal hCES2A represents a feasible strategy to mitigate irinotecan-triggered gut toxicity (ITGT), but the orally active, selective, and efficacious hCES2A inhibitors are rarely reported. Here, a novel drug-like hCES2A inhibitor was developed via three rounds of structure-based drug design (SBDD) and structural optimization. Initially, donepezil was identified as a moderate hCES2A inhibitor from 2000 US Food and Drug Administration (FDA)-approved drugs. Following two rounds of SBDD and structural optimization, a donepezil derivative (B7) was identified as a strong reversible hCES2A inhibitor. Subsequently, nine B7 carbamates were rationally designed, synthesized and biologically assayed. Among all synthesized carbamates, C3 showed the most potent time-dependent inhibition on hCES2A (IC₅₀ = 0.56 nmol/L), excellent specificity and favorable drug-like properties. C3 could covalently modify the catalytic serine of hCES2A with high selectivity, while this agent also showed favorable safety profiles, high intestinal exposure, and impressive effects for ameliorating ITGT in both human intestinal organoids and tumor-bearing mice. Collectively, this study showcases a rational strategy for developing drug-like and serine-targeting covalent inhibitors against target serine hydrolase(s), while C3 emerges as a promising orally active drug candidate for ameliorating ITGT.

Eight butyl-phthalides, senkyunolide K(1), senkyunolide N(2), butylphthalide(3), senkyunolide I(4), senkyunolide H(5),(Z)-butylidenephthalide(6),(Z)-ligustilide(7), and 3-butylidene-7-hydroxyphthalide(8) were isolated from the aerial part of Ligusticum sinense by column chromatography on silica gel column, ODS, Sephadex LH-20 and semi-preparative HPLC. Their structures were elucidated on the basis of spectroscopic and chemical data, especially NMR and MS. Compound 1 was a new butyl-phthalide and compounds 2-8 were isolated from the aerial part of L. sinense for the first time. Furthermore, the inhibitory activities of compounds 1-8 against the nitric oxide(NO) production induced by lipopolysaccharide(LPS) in mouse RAW264.7 macrophages in vitro were evaluated. The results showed that compounds 1-8 exerted inhibitory activities on NO production with IC_(50) of 19.34-42.16 μmol·L~(-1).
Animals ; Mice ; Nitric Oxide/biosynthesis* ; Ligusticum/chemistry* ; Benzofurans/isolation & purification* ; Drugs, Chinese Herbal/isolation & purification* ; Macrophages/immunology* ; RAW 264.7 Cells ; Molecular Structure

This study aims to evaluate the therapeutic effect of Alpiniae Oxyphyllae Fructus-Saposhnikoviae Radix(AOF-SR) in a diabetic kidney disease(DKD) mouse model, explore its potential mechanism in regulating the NOD-like receptor protein 3(NLRP3) inflammasome via phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) signaling pathway, and provide new theoretical support for traditional Chinese medicine(TCM) intervention in DKD. Using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), the active ingredients and potential targets of AOF-SR were screened and its molecular mechanisms were investigated through molecular docking, molecular dynamics simulations, and experimental validation. The db/db mice were randomly divided into four groups: model group, low-dose AOF-SR group, high-dose AOF-SR group, and canagliflozin group. The db/m mice served as normal group. After one week of acclimatization, the mice underwent drug intervention. Starting from one week after treatment, body weight, blood glucose levels, and 24-hour urinary protein(24hUP) were measured every two weeks. After 13 weeks of administration, tissue collection and indicator detection were performed. Blood glucose, 24hUP, urinary microalbumin(mAlb), serum creatinine(Scr), and blood urea nitrogen(BUN) levels were determined. Pathological changes in kidney tissue were observed using hematoxylin-eosin(HE) staining. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of serum IL-1β, IL-18, and caspase-1, while RT-qPCR was employed to measure the mRNA expression levels of IL-1β, IL-18, caspase-1, and NLRP3. Western blot was used to assess the protein expression levels of NLRP3, PI3K, p-Akt, Akt, p-mTOR, and mTOR. Network pharmacology analysis indicated that wogonin, pinocembrin, hancinol, and kaempferol were the core compounds for drug treatment of the disease. Molecular docking and molecular dynamics simulations showed that core compounds, particularly wogonin, could specifically bind to PIK3R1, thereby regulating the PI3K/Akt/mTOR pathway. The experimental results indicated that both low and high doses of AOF-SR and canagliflozin significantly reduced blood glucose, 24hUP, mAlb, Scr, and BUN levels in db/db mice, while improving kidney pathological damage and inflammatory cell infiltration. Moreover, the treatments reduced the mRNA expression levels of caspase-1, IL-1β, and IL-18 in the kidneys of db/db mice, as well as the secretion of these factors in the serum. The drugs also inhibited the mRNA and protein expression levels of NLRP3 in the kidneys of db/db mice and decreased the protein levels of PI3K, p-Akt/Akt, and p-mTOR/mTOR. In conclusion, AOF-SR may improve kidney inflammation in DKD mice by regulating the PI3K/Akt/mTOR signaling pathway and inhibiting NLRP3 inflammasome activation.
Animals ; Mice ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Signal Transduction/drug effects* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Diabetic Nephropathies/metabolism* ; Inflammasomes/drug effects* ; Male ; Drugs, Chinese Herbal/chemistry* ; Humans ; Mice, Inbred C57BL

OBJECTIVE: To investigate the anti-tumor effects of cinobufacini (CINO) on hepatocellular carcinoma (HCC) induced by des-gamma-carboxy-prothrombin (DCP) and to uncover the underlying mechanisms. METHODS: The inhibitory effect of CINO on HCC cell proliferation was evaluated using the cell counting kit-8 method, and the apoptosis rate was quantified using flow cytometry. Immunofluorescence and Western blot analyses were used to investigate the differential expression of proteins associated with cell growth, apoptosis, migration, and invasion pathways after CINO treatment. The therapeutic potential of CINO for HCC was confirmed, and the possibility of combining cinobufacini with c-Met inhibitor for the treatment of primary HCC was further validated by in vivo experiments. RESULTS: Under the induction of DCP, CINO inhibited the activity of HCC cells, induced apoptosis, and inhibited migration and invasion. Upon the induction of DCP, CINO regulated c-Met activation and the activation of the phosphatidylinositol-3 kinase/protein kinase B (PI3K/AKT) and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (MEK/ERK) pathways. In a mouse model of HCC, CINO exhibited significant antitumor effects by inhibiting the phosphorylation of c-Met and the downstream PI3K/AKT and MEK/ERK pathways in tumor tissues. CONCLUSIONS CINO inhibited HCC cell growth, promoted apoptosis, and suppressed HCC cell invasion and migration by targeting c-Met and PI3K/AKT and MEK/ERK signaling pathways under DCP induction.
Carcinoma, Hepatocellular/drug therapy* ; Proto-Oncogene Proteins c-met/metabolism* ; Liver Neoplasms/drug therapy* ; Signal Transduction/drug effects* ; Animals ; Humans ; Cell Movement/drug effects* ; Apoptosis/drug effects* ; Cell Proliferation/drug effects* ; Amphibian Venoms/therapeutic use* ; Cell Line, Tumor ; Neoplasm Metastasis ; Cell Survival/drug effects* ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Neoplasm Invasiveness ; Mice, Inbred BALB C ; Mice, Nude ; Mice ; Male ; Bufanolides/therapeutic use* ; Protein Precursors ; Prothrombin ; Biomarkers

Antibiotic adjuvants offer a promising strategy for restoring antibiotic sensitivity, expanding antibacterial spectra, and reducing required dosages. Previously, compound 15 was identified as a potential adjuvant for Polymyxin B (PB) against multidrug-resistant (MDR) Pseudomonas aeruginosa DK2; however, its clinical utility was hindered by high cytotoxicity, uncertain in vivo efficacy, and an unclear synergetic mechanism. To address these challenges, we synthesized and evaluated a series of novel benzamide derivatives, with A22 emerging as a particularly promising candidate. A22 demonstrated potent synergistic activity to PB, minimal cytotoxicity, improved water solubility, and broad-spectrum synergism of polymyxins against various clinically isolated MDR Gram-negative strains. In vivo studies using Caenorhabditis elegans and mouse models further confirmed the efficacy of A22. Moreover, A22 effectively suppressed the development of PB resistance in Pseudomonas aeruginosa DK2. Mechanistic investigations revealed that A22 enhances polymyxins activity by inducing reactive oxygen species production, reducing ATP levels, increasing NOX activity, and inhibiting biofilm formation, leading to bacterial death. These findings position A22 as a highly promising candidate for the development of polymyxin adjuvants, offering a robust approach to combating MDR Gram-negative bacterial infections.