Chemical Biology & Drug Design最新文献

Dl-3-n-Butylphthalide (NBP) has been reported to relieve neuronal damage by suppressing excessive autophagy. This study explored whether NBP could protect neurons after spinal cord injury (SCI) by inhibiting excessive autophagy, and its intrinsic mechanism were investigated. In methodology, this paper detected the Hippo/YAP pathway activity and autophagy in peripheral blood of SCI patients. A SCI cell model and a rat SCI model were established. Through a series of assays and experimental validation, the effect and mechanism of NBP on neuronal damage after SCI were analyzed. As a result, the activated Hippo pathway, decreased YAP protein, and increased p-YAP, Beclin 1, and LC3 II/I proteins were monitored in peripheral blood of SCI patients. OGD treatment enhanced apoptosis and autophagy, activated the Hippo/YAP pathway, and enhanced YAP nuclear translocation in PC12 cells. NBP treatment eliminated these effects of OGD on PC12 cells. YAP silencing reversed the suppression of NBP on the OGD-induced PC12 cell apoptosis and autophagy. In vivo, the inhibition of NBP on neuronal injury, the Hippo/YAP pathway activity, and autophagy was abolished by YAP silencing. Thus, NBP attenuates autophagy to alleviate neuronal apoptosis after SCI via inactivating the Hippo/YAP pathway. NBP may be useful in SCI treatment clinically.

The kappa opioid receptor (KOR) is one of class A G-protein-coupled receptors (GPCRs), playing important roles in pain sensation. The unique analgesic activity of KOR requires KOR activation that recruits downstream effectors. It is noted that KOR primarily couples to the G_i/o family proteins in the process of KOR signaling that contain the conventional (G_i1, G_i2, G_i3, G_oA, and G_oB) and nonconventional (G_z and G_g) subtypes. The molecular mechanisms governing KOR signaling—particularly its selectivity for G_i/o protein subtypes and the pathway specificity of its ligands—remain unclear. Furthermore, the structural and energetic sequence of events during the activation of KOR and its cognate G_i/o proteins is poorly understood. This lack of knowledge hinders the structure-based design of pharmacophores targeting the KOR/G_i/o complex. It suggests that further research and investigation are required to analyze the crystal structure of the agonists/KOR complexes and various intermediate states in the KOR activation pathway. Some improved enhanced sampling methods, such as umbrella sampling, metadynamics, and Markov State Model methods, can characterize the interaction between GPCRs and different G protein subtypes after specific ligands binding, and the free energy landscapes along the ligand binding pathway. In this review, we discuss the research advances in the molecular mechanisms of KOR signaling. We also present a brief overview of computational conformational sampling methods based on molecular dynamics, including the activation mechanisms, allosteric effects, and actions of biased ligands of GPCRs to describe their activation energy landscape. It can provide an insight into evaluate the convergence of free energy surfaces along coordinates of functional interest, which is helpful to understand the role of GPCR conformational ensembles in intracellular signal transduction.

This study aimed to investigate the effects and mechanisms of Ganoderic acid A (GAA) on lung injury associated with systemic inflammatory response syndrome (SIRS). Forty Sprague Dawley rats were divided into four groups: Control group, GAA group (GAA, 40 mg/kg), lipopolysaccharide (LPS) group (LPS, 10 mg/kg), and LPS + GAA group. Lung tissue, bronchoalveolar lavage fluid (BALF), and blood samples were analyzed for cell counts, protein levels, and histology, inflammatory cytokines, oxidative stress markers, and macrophage polarization. Western blot was used to assess the TLR4/NF-κB pathway. GAA treatment significantly attenuated LPS-induced lung injury, as shown by reduced lung tissue water content and BALF protein levels. Histological analysis confirmed less severe lung injury in GAA-treated rats. GAA decreased inflammatory cell numbers in BALF, lowered inflammatory cytokine levels in serum and BALF, and reduced oxidative stress levels in lung tissue. Flow cytometry indicated that GAA promoted M2 macrophage polarization, and Western blot analysis revealed inhibition of TLR4/NF-κB pathway activation. GAA ameliorates lung injury induced by sepsis-related SIRS in rats through anti-inflammatory, anti-oxidative, and immunomodulatory effects, supporting its potential therapeutic value in sepsis treatment.

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths worldwide. Plumbagin (PLBG), a naturally occurring active naphthoquinone derived from Chinese herbal plants, exhibits anti-cancer effects across multiple cancer types. However, the mechanisms underlying PLBG-induced anti-tumor activity in NSCLC remain incompletely understood. Our study demonstrated that PLBG significantly inhibited NSCLC cell proliferation and induced apoptosis by elevating intracellular and mitochondrial reactive oxygen species (ROS), leading to mitochondrial dysfunction. The ROS scavenger N-acetylcysteine (NAC) abrogated PLBG-induced apoptosis and restored cell viability. Notably, RNA sequencing analysis revealed that differentially expressed genes in PLBG-treated cells were enriched in the cytosolic DNA-sensing pathway and STING pathway. Mechanistically, PLBG treatment activated the STING pathway and upregulated key chemokines (CXCL10, CXCL9, CCL5) in NSCLC cells. Critically, STING inhibition by H151 attenuated PLBG-induced apoptosis, confirming the essential role of STING. These results suggest that PLBG exerts potent anti-NSCLC effects through ROS-mediated apoptosis, STING pathway activation, and chemokine induction, while concurrently inhibiting pro-survival signaling. These findings position PLBG as a promising therapeutic candidate for NSCLC treatment.

BRAF is one of the most commonly mutated oncogenes in human cancers. More than 90% of BRAF mutations are associated with malignant melanoma. Given the pivotal role of BRAF^V600E/WT mutations in melanoma progression and therapy resistance, our study focused on the design of phenyl-substituted pyrimidin-benzenesulfonamide hybrids in the [αC-OUT/DFG-IN] conformation, inspired by previously synthesized molecules structurally related to FDA-approved BRAF inhibitors. A total of ten derivatives were synthesized, and their ADME-T properties, in silico binding affinities, in vitro cytotoxic activities against a melanoma cell line and BRAF^V600E/WT kinase assay were thoroughly evaluated. All compounds exhibit selective and stronger affinity for the BRAF^V600E mutant over the wild-type BRAF protein and also adhere to Lipinski's Rule of Five. Overall, both computational and biological evaluations support that the synthesized compounds, particularly VA03, exhibit greater potency and selectivity toward the BRAF^V600E mutant protein. Furthermore, the presence of electron-withdrawing groups at the R₁ position appears to significantly enhance the cytotoxic activity of these derivatives.

Fibroblast Activation Protein (FAP) is highly expressed in the tumor microenvironment, promoting cancer growth and spread. FAP inhibitors (FAPIs) labeled with radionuclides are increasingly used for cancer diagnosis and therapy. The present study aims to explore how structural features relate to the inhibitory action of radiopharmaceuticals, representing a novel approach in the field of radiopharmacy. The 2D-QSAR using multiple linear regression analysis via the stepwise variable selection method showed promising results for both internal and external predictive ability of the model (R²_train = 0.877, Q²_LOO = 0.830, pred_R² = 0.740). This analysis based on the genetic algorithm was also robust (R²_train = 0.846, Q²_LOO = 0.768, pred_R² = 0.608). A 3D-QSAR model using partial least squares analysis showed better parametric results for CoMFA descriptors (R² = 0.988, Q²_LOO = 0.518 and pred_R² = 0.642) than the CoMSIA model as well. Our findings revealed that the steric, hydrophobic, and hydrogen-bonding properties notably impact the pIC₅₀ values of FAPI radiopharmaceuticals. Based on virtual screening on the FDA-approved drugs, 23 potential inhibitors of the FAP enzyme were identified. To the best of our knowledge, this is the first QSAR study on radiopharmaceuticals with FAP inhibitory action, the results of which can be helpful in designing more potent ones.

The antioxidant and enzyme inhibition properties of the isoflavone genistein (1) and the alkaloid 11-α-hydroxyerysotrine (2) isolated from the leaves of Erythrina speciosa were assessed. Both compounds exhibited notable in vitro antioxidant activities; 11-α-hydroxyerysotrine (2) demonstrated stronger effects than genistein in DPPH, ABTS, CUPRAC, and FRAP assays. On the other hand, genistein (1) demonstrated a higher metal chelating activity than 11-α-hydroxyerysotrine (2). Regarding enzyme inhibition, 11-α-hydroxyerysotrine (2) inhibited both acetyl- (AchE) and butyryl- (BchE) cholinesterases, though to a lesser extent than the standard drug galanthamine. Both compounds inhibited tyrosinase, yet a good inhibition was observed for 11-α-hydroxyerysotrine (2) as compared to genistein (1). Genistein (1) showed a lower α-amylase inhibition effect (IC₅₀: 3.43 mg/mL, p < 0.05) compared to the standard acarbose (IC₅₀: 0.80 mg/mL). Regarding α-glucosidase inhibition, genistein (1) (IC₅₀: 1.02 mg/mL, p < 0.05) was more active than acarbose (IC₅₀: 1.78 mg/mL). 11-α-Hydroxyerysotrine (2) exhibited lower α-amylase (IC₅₀: 4.09 mg/mL) and α-glucosidase (IC₅₀: 4.48 mg/mL) inhibition effects. The in vitro biological results were further supported by network pharmacology approaches on Alzheimer's disease and in silico studies performed on AChE, BChE, tyrosinase, α-amylase, and β-glucosidase enzymes. The results of our study suggest 11-α-hydroxyerysotrine as a potential drug candidate for further investigation in managing oxidative stress-related conditions, Alzheimer's disease, and hyperpigmentation disorders.

Verbascum L., a member of the Scrophulariaceae family, is the second-largest genus in Turkish flora. It is represented by over 250 species, many of which have been used as folk medicine. This study aims to determine the cholinesterase inhibitory potential of secondary metabolites of Verbascum uschakense (Murb.) Hub.-Mor, an endemic species to Türkiye that has not been studied phytochemically before. Gluroside, an iridoid glucoside, was isolated from V. uschakense through acetylcholinesterase (AChE) inhibitory activity-guided fractionation alongside four other iridoid glucosides: ajugol, harpagide, aucubin, and catalpol. Additionally, three phenylethanoid glycosides—verbascoside, martinoside, and forsythoside B—were isolated from the antioxidant fractions evaluated using DPPH radical scavenging activity. Gluroside emerged as the most active compound against butyrylcholinesterase (BChE) with an IC₅₀ of 2.5 ± 0.02 μg/mL, exhibiting selectivity over AChE (37.69% inhibition at 200 μg/mL). Molecular modeling predicted strong electrostatic interactions between the glucosides and the catalytic residues of BChE. This is the first report of the isolation of gluroside from a Verbascum species and its cholinesterase inhibitory activity, underpinning the importance of V. uschakense and its secondary metabolites as a new class of cholinesterase inhibitors.

Diabetic retinopathy (DR) remains a major cause of vision loss among working-age individuals, significantly impairing quality of life in diabetic patients. While no definitive cure exists, Procyanidin (PRO), a polyphenolic compound, has shown potential in mitigating diabetes-related complications. However, its mechanism of action in DR remains poorly understood. To explore this, we established an in vitro high glucose (HG) model using human retinal microvascular endothelial cells (hRMECs) and an in vivo diabetic rat model. Cells were cultured in normal glucose (NG, 5 mM) or HG (30 mM) for 48 h, followed by PRO treatment. Techniques including qRT-PCR, Western blotting, flow cytometry, histological staining, Transwell, tube formation, chromatin immunoprecipitation (ChIP), and dual-luciferase assays were employed. PRO treatment conferred protection against DR; however, this effect was reversed upon knockdown of activating transcription factor 1 (ATF1). Mechanistically, ATF1 enhanced transcription of synoviolin 1 (SYVN1), promoting HMGB1 degradation via ubiquitination and suppressing the HMGB1/toll-like receptor 4 (TLR4) signaling pathway. Findings from the in vitro model were validated in vivo. In conclusion, PRO alleviates DR by regulating the ATF1/SYVN1/HMGB1 axis and inhibiting pro-inflammatory signaling. These results provide novel insights into the molecular mechanism of PRO's protective role in DR and support its therapeutic potential.

Oligomycin A, initially identified as a macrolide antibiotic and a mitochondrial ATP synthase inhibitor, has recently transitioned from a laboratory tool to a multifaceted agent with promising therapeutic and industrial applications. Its irreversible inhibition of the F₀ subunit interrupts ATP synthesis and informs about metabolic susceptibilities in neoplastic cells, such as the Warburg effect and reversal of multidrug resistance by P-glycoprotein inhibition. Guided by structural studies of its interaction with the c10-ring of ATP synthase, analogs like bedaquiline were rationally designed as antibacterial candidates, and the analog spiropiperidine derivatives were inspired by improving ischemia–reperfusion injury. Although this derivative has great potential, clinical translation is limited by systemic toxicity, poor solubility, and environmental persistence. Emerging approaches like PEGylation and combination therapies (e.g., with docetaxel) have started to address selectivity and off-target effects. There are still challenges in balancing efficacy, safety, and environmental impact. This review summarizes the current knowledge and mechanisms of action of oligomycin A and its derivatives that should be of interest in the design of bioactive agents with potential therapeutic applications. This is intended to serve as a motivator for moving forward with future research avenues toward optimizing Oligomycin A-based therapeutics to derive as much of the potential benefit as possible while mitigating the harms associated.