Acta Pharmacologica Sinica最新文献

Suppression of neuroinflammation using small molecule compounds targeting the key pathways in microglial inflammation has attracted great interest. Recently, increasing attention has been gained to the role of the second bromodomain (BD2) of the bromodomain and extra-terminal (BET) proteins, while its effect and molecular mechanism on microglial inflammation has not yet been explored. In this study, we evaluated the therapeutic effects of ABBV-744, a BD2 high selective BET inhibitor, on lipopolysaccharide (LPS)-induced microglial inflammation in vitro and in vivo, and explored the key pathways by which ABBV-744 regulated microglia-mediated neuroinflammation. We found that pretreatment of ABBV-744 concentration-dependently inhibited the expression of LPS-induced inflammatory mediators/enzymes including NO, TNF-α, IL-1β, IL-6, iNOS, and COX-2 in BV-2 microglial cells. These effects were validated in LPS-treated primary microglial cells. Furthermore, we observed that administration of ABBV-744 significantly alleviated LPS-induced activation of microglia and transcriptional levels of pro-inflammatory factors TNF-α and IL-1β in mouse hippocampus and cortex. RNA-Sequencing (RNA-seq) analysis revealed that ABBV-744 induced 508 differentially expressed genes (DEGs) in LPS-stimulated BV-2 cells, and gene enrichment and gene expression network analysis verified its regulation on activated microglial genes and inflammatory pathways. We demonstrated that pretreatment of ABBV-744 significantly reduced the expression levels of basic leucine zipper ATF-like transcription factor 2 (BATF2) and interferon regulatory factor 4 (IRF4), and suppressed JAK-STAT signaling pathway in LPS-stimulated BV-2 cells and mice, suggesting that the anti-neuroinflammatory effect of ABBV-744 might be associated with regulation of BATF2-IRF4-STAT1/3/5 pathway, which was confirmed by gene knockdown experiments. This study demonstrates the effect of a BD2 high selective BET inhibitor, ABBV-744, against microglial inflammation, and reveals a BATF2-IRF4-STAT1/3/5 pathway in regulation of microglial inflammation, which might provide new clues for discovery of effective therapeutic strategy against neuroinflammation.

The endothelium, lining the inner surface of blood vessels and spanning approximately 3 m², serves as the largest organ in the body. Comprised of endothelial cells, the endothelium interacts with other bodily components including the bloodstream, circulating cells, and the lymphatic system. Functionally, the endothelium primarily synchronizes vascular tone (by balancing vasodilation and vasoconstriction) and prevents vascular inflammation and pathologies. Consequently, endothelial dysfunction disrupts vascular homeostasis, leading to vascular injuries and diseases such as cardiovascular, cerebral, and metabolic diseases. In this opinion/perspective piece, we explore the recently identified mechanisms of endothelial dysfunction across various disease subsets and critically evaluate the strengths and limitations of current therapeutic interventions at the pre-clinical level.

Identification of compounds to modulate NADPH metabolism is crucial for understanding complex diseases and developing effective therapies. However, the complex nature of NADPH metabolism poses challenges in achieving this goal. In this study, we proposed a novel strategy named NADPHnet to predict key proteins and drug-target interactions related to NADPH metabolism via network-based methods. Different from traditional approaches only focusing on one single protein, NADPHnet could screen compounds to modulate NADPH metabolism from a comprehensive view. Specifically, NADPHnet identified key proteins involved in regulation of NADPH metabolism using network-based methods, and characterized the impact of natural products on NADPH metabolism using a combined score, NADPH-Score. NADPHnet demonstrated a broader applicability domain and improved accuracy in the external validation set. This approach was further employed along with molecular docking to identify 27 compounds from a natural product library, 6 of which exhibited concentration-dependent changes of cellular NADPH level within 100 μM, with Oxyberberine showing promising effects even at 10 μM. Mechanistic and pathological analyses of Oxyberberine suggest potential novel mechanisms to affect diabetes and cancer. Overall, NADPHnet offers a promising method for prediction of NADPH metabolism modulation and advances drug discovery for complex diseases.

Cardiac fibrosis is a detrimental pathological process, which constitutes the key factor for adverse cardiac structural remodeling leading to heart failure and other critical conditions. Circular RNAs (circRNAs) have emerged as important regulators of various cardiovascular diseases. It is known that several circRNAs regulate gene expression and pathological processes by binding miRNAs. In this study we investigated whether a novel circRNA, named circNSD1, and miR-429-3p formed an axis that controls cardiac fibrosis. We established a mouse model of myocardial infarction (MI) for in vivo studies and a cellular model of cardiac fibrogenesis in primary cultured mouse cardiac fibroblasts treated with TGF-β1. We showed that miR-429-3p was markedly downregulated in the cardiac fibrosis models. Through gain- and loss-of-function studies we confirmed miR-429-3p as a negative regulator of cardiac fibrosis. In searching for the upstream regulator of miR-429-3p, we identified circNSD1 that we subsequently demonstrated as an endogenous sponge of miR-429-3p. In MI mice, knockdown of circNSD1 alleviated cardiac fibrosis. Moreover, silence of human circNSD1 suppressed the proliferation and collagen production in human cardiac fibroblasts in vitro. We revealed that circNSD1 directly bound miR-429-3p, thereby upregulating SULF1 expression and activating the Wnt/β-catenin pathway. Collectively, circNSD1 may be a novel target for the treatment of cardiac fibrosis and associated cardiac disease.

This study aimed to analyze potential ethnic disparities in the dose-exposure-response relationships of trilaciclib, a first-in-class intravenous cyclin-dependent kinase 4/6 inhibitor for treating chemotherapy-induced myelosuppression in patients with extensive-stage small cell lung cancer (ES-SCLC). This investigation focused on characterizing these relationships in both Chinese and non-Chinese patients to further refine the dosing regimen for trilaciclib in Chinese patients with ES-SCLC. Population pharmacokinetic (PopPK) and exposure-response (E-R) analyses were conducted using pooled data from four randomized phase 2/3 trials involving Chinese and non-Chinese patients with ES-SCLC. PopPK analysis revealed that trilaciclib clearance in Chinese patients was approximately 17% higher than that in non-Chinese patients with ES-SCLC. Sex and body surface area influenced trilaciclib pharmacokinetics in both populations but did not exert a significant clinical impact. E-R analysis demonstrated that trilaciclib exposure increased with a dosage escalation from 200 to 280 mg/m², without notable changes in myeloprotective or antitumor efficacy. However, the incidence of infusion site reactions, headaches, and phlebitis/thrombophlebitis rose with increasing trilaciclib exposure in both Chinese and non-Chinese patients with ES-SCLC. These findings suggest no substantial ethnic disparities in the dose-exposure-response relationship between Chinese and non-Chinese patients. They support the adoption of a 240-mg/m² intravenous 3-day or 5-day dosing regimen for trilaciclib in Chinese patients with ES-SCLC.

Excessive dietary calories lead to systemic metabolic disorders, disturb hepatic lipid metabolism, and aggravate nonalcoholic steatohepatitis (NASH). Bile acids (BAs) play key roles in regulating nutrition absorption and systemic energy homeostasis. Resmetirom is a selective thyroid hormone receptor β (THRβ) agonist and the first approved drug for NASH treatment. It is well known that the THRβ activation could promote intrahepatic lipid catabolism and improve mitochondrial function, however, its effects on intestinal lipid absorption and BA compositions remain unknown. In the present study, the choline-deficient, L-amino acid defined, high-fat diet (CDAHFD) and high-fat diet plus CCl₄ (HFD+CCl₄)-induced NASH mice were used to evaluate the effects of resmetirom on lipid and BA composition. We showed that resmetirom administration (10 mg·kg^-1·d^-1, i.g.) significantly altered hepatic lipid composition, especially reduced the C18:2 fatty acyl chain-containing triglyceride (TG) and phosphatidylcholine (PC) in the two NASH mouse models, suggesting that THRβ activation inhibited intestinal lipid absorption since C18:2 fatty acid could be obtained only from diet. Targeted analysis of BAs showed that resmetirom treatment markedly reduced the hepatic and intestinal 12-OH to non-12-OH BAs ratio by suppressing cytochrome P450 8B1 (CYP8B1) expression in both NASH mouse models. The direct inhibition by resmetirom on intestinal lipid absorption was further verified by the BODIPY gavage and the oral fat tolerance test. In addition, disturbance of the altered BA profiles by exogenous cholic acid (CA) supplementation abolished the inhibitory effects of resmetirom on intestinal lipid absorption in both normal and CDAHFD-fed mice, suggesting that resmetirom inhibited intestinal lipid absorption by reducing 12-OH BAs content. In conclusion, we discovered a novel mechanism of THRβ agonists on NASH treatment by inhibiting intestinal lipid absorption through remodeling BAs composition, which highlights the multiple regulation of THRβ activation on lipid metabolism and extends the current knowledge on the action mechanisms of THRβ agonists in NASH treatment.

Bruton's tyrosine kinase (BTK) has emerged as a therapeutic target for B-cell malignancies, which is substantiated by the efficacy of various irreversible or reversible BTK inhibitors. However, on-target BTK mutations facilitating evasion from BTK inhibition lead to resistance that limits the therapeutic efficacy of BTK inhibitors. In this study we employed structure-based drug design strategies based on established BTK inhibitors and yielded a series of BTK targeting compounds. Among them, compound S-016 bearing a unique tricyclic structure exhibited potent BTK kinase inhibitory activity with an IC₅₀ value of 0.5 nM, comparable to a commercially available BTK inhibitor ibrutinib (IC₅₀ = 0.4 nM). S-016, as a novel irreversible BTK inhibitor, displayed superior kinase selectivity compared to ibrutinib and significant therapeutic effects against B-cell lymphoma both in vitro and in vivo. Furthermore, we generated BTK inhibitor-resistant lymphoma cells harboring BTK C481F or A428D to explore strategies for overcoming resistance. Co-culture of these DLBCL cells with M0 macrophages led to the polarization of M0 macrophages toward the M2 phenotype, a process known to support tumor progression. Intriguingly, we demonstrated that SYHA1813, a compound targeting both VEGFR and CSF1R, effectively reshaped the tumor microenvironment (TME) and significantly overcame the acquired resistance to BTK inhibitors in both BTK-mutated and wild-type BTK DLBCL models by inhibiting angiogenesis and modulating macrophage polarization. Overall, this study not only promotes the development of new BTK inhibitors but also offers innovative treatment strategies for B-cell lymphomas, including those with BTK mutations.

Kv1.3 belongs to the voltage-gated potassium (Kv) channel family, which is widely expressed in the central nervous system and associated with a variety of neuropsychiatric disorders. Kv1.3 is highly expressed in the olfactory bulb and piriform cortex and involved in the process of odor perception and nutrient metabolism in animals. Previous studies have explored the function of Kv1.3 in olfactory bulb, while the role of Kv1.3 in piriform cortex was less known. In this study, we investigated the neuronal changes of piriform cortex and feeding behavior after smell stimulation, thus revealing a link between the olfactory sensation and body weight in Kv1.3 KO mice. Coronal slices including the anterior piriform cortex were prepared, whole-cell recording and Ca²⁺ imaging of pyramidal neurons were conducted. We showed that the firing frequency evoked by depolarization pulses and Ca²⁺ influx evoked by high K⁺ solution were significantly increased in pyramidal neurons of Kv1.3 knockout (KO) mice compared to WT mice. Western blotting and immunofluorescence analyses revealed that the downstream signaling molecules CaMKII and PKCα were activated in piriform cortex of Kv1.3 KO mice. Pyramidal neurons in Kv1.3 KO mice exhibited significantly reduced paired-pulse ratio and increased presynaptic Cav2.1 expression, proving that the presynaptic vesicle release might be elevated by Ca²⁺ influx. Using Golgi staining, we found significantly increased dendritic spine density of pyramidal neurons in Kv1.3 KO mice, supporting the stronger postsynaptic responses in these neurons. In olfactory recognition and feeding behavior tests, we showed that Kv1.3 conditional knockout or cannula injection of 5-(4-phenoxybutoxy) psoralen, a Kv1.3 channel blocker, in piriform cortex both elevated the olfactory recognition index and altered the feeding behavior in mice. In summary, Kv1.3 is a key molecule in regulating neuronal activity of the piriform cortex, which may lay a foundation for the treatment of diseases related to piriform cortex and olfactory detection.