Acta Pharmacologica Sinica最新文献

Surgery followed by adjuvant chemoradiation is the standard treatment for glioblastoma multiforme (GBM). Temozolomide (TMZ) is the only first-line chemotherapeutic drug approved by the US Food and Drug Administration for the treatment of GBM. Acquired chemoresistance to TMZ is the primary cause of treatment failure, resulting in recurrence and a poor prognosis. O6-methylguanine DNA methyltransferase (MGMT) overexpression and loss of function mutations targeting mismatch repair (MMR) are the major mechanisms TMZ-resistance found in GBM cells. In this study we developed a new alkylating agent that could overcome TMZ resistance. We designed a new chloroethylnitrosourea analog HJ03, and demonstrated that HJ03 was more potent than TMZ in inhibiting GBM cell lines U251 (MGMT^-, MMR⁺), U87 (MGMT^-, MMR^-) and T98G (MGMT⁺, MMR⁺) as well as colorectal cancer cell line HCT116 (MGMT⁺, MMR^-) with MGMT overexpression or MMR dysfunction. Furthermore, HJ03 exerted a dual synergistic attack effect by inducing DNA damage and ferroptosis in U251, U87 and T98G cells. We showed that HJ03 caused U251 and T98G cells to be arrested in G2/M phase and undergo apoptosis by inducing the formation of DNA adducts and interstrand crosslinks. In U251, U87 and T98G cells, HJ03 promoted extensive ferroptosis by upregulating p53 and ATF3 expression while downregulating SLC7A11, leading to intracellular accumulation of ROS and Fe²⁺ along with increased MDA levels. Pharmacokinetic study showed that HJ03 crossed the blood-brain barrier more efficiently than TMZ and exhibited lower levels of bone marrow toxicity. In model mice bearing orthotopic CT2A GBM tumors, administration of HJ03 (20 mg/kg, i.g. 5 consecutive days per week for 3 weeks) significantly prolonged the lifespan. Furthermore, HJ03 synergized with radiotherapy and an anti-PD-1 monoclonal antibody to dramatically prolong mouse survival. Thus, HJ03 emerges as a promising novel candidate for GBM treatment, particularly for patients with TMZ-resistant tumors.

Colorectal cancer (CRC) remains a leading cause of cancer-related morbidity and mortality worldwide, necessitating the discovery of novel therapeutic agents. Sinomenine (Sin), a natural product derived from traditional Chinese medicine, has been extensively modified to enhance its therapeutic potential. Here, we synthesized Sino-C, a novel Sin derivative, and evaluated its anti-CRC activity. Sino-C exhibited significant anticancer effects both in vitro and in vivo. Mechanistically, Sino-C upregulated cholesterol homeostasis-related genes and increased intracellular cholesterol levels in CRC cells. Cholesterol depletion with methyl-β-cyclodextrin (MβCD) alleviated Sino-C-induced cholesterol accumulation, reduced cell death, and reversed cleaved PARP expression, indicating cholesterol imbalance as a critical mediator of Sino-C's activity. Furthermore, Sino-C-induced cholesterol imbalance promoted lipid peroxidation and endoplasmic reticulum (ER) stress, contributing to cell death. The antioxidant vitamin E (Ve), N-acetylcysteine (NAC), or PERK inhibitor GSK2656157 could reverse these effects of Sino-C. Clinical correlation analysis further revealed that high expression of Sino-C-upregulated cholesterol homeostasis genes was linked to better survival outcomes in CRC cohorts. In conclusion, this study highlights the therapeutic potential of Sino-C in CRC. In vitro mechanistic findings suggest that Sino-C exerts its anticancer effects through modulation of cholesterol metabolism, positioning natural product derivatives as valuable candidates for further development.

Pathological cardiac hypertrophy is associated with intricate changes that can eventually lead to heart failure. Galangin is a natural flavonoid derived from the rhizome of the galangal plant that has shown protective effects against a variety of cardiomyopathies. Galangin undergoes methylation at the third hydroxyl position to form Galangin 3-methyl ether (G3-ME), thus increasing its lipophilicity, thereby facilitating its cellular entry and regulatory effects. In this study, we investigated the effects of G3-ME on hypertrophic cardiomyopathy (HCM) and the underlying mechanisms. Two established transgenic mouse models of HCM, i.e., Myh6^R404Q and Tnnt2^R109Q mice, were used for in vivo studies. For in vitro experiments, H9c2, a rat cardiomyocyte cell line, along with human embryonic stem cell-derived cardiomyocytes (hESC-CMs), were exposed to angiotensin II (Ang II, 1 μM). We showed that G3-ME (2.5-20 μM) dose-dependently inhibited the expression of pathological cardiac hypertrophy marker genes Nppa and Nppb in Ang II-treated H9c2 cells. G3-ME (5 μM) effectively mitigated the Ang II-induced expansion of H9c2 cells and hESC-CMs. In the two HCM mouse models, administration of G3-ME (20 or 50 mg·kg^-1·d^-1, i.g.) for 4 weeks significantly improved the cardiac hypertrophy phenotype. By conducting RNA sequencing combined with network pharmacology, we identified histone deacetylase 2 (HDAC2) as the direct target of G3-ME in H9c2 cells. We demonstrated that G3-ME inhibited both the phosphorylation of HDAC2 and the PI3K-AKT signaling pathway during the cardiac hypertrophy process in vivo and in vitro. Knockdown of HDAC2 resulted in inhibition of cardiac hypertrophy, whereas its overexpression facilitated cardiac hypertrophy through the PI3K-AKT signaling pathway. In conclusion, G3-ME attenuates pathological cardiac hypertrophy in vivo and in vitro by targeting HDAC2, leading to the inactivation of the PI3K-AKT signaling pathway. G3-ME may serve as a promising option for addressing hypertrophic cardiomyopathy.

As antipsychotic administration often persists for a lifetime, antipsychotic-induced cardiotoxicity (AIC) becomes a significant and potentially life-threatening side effect. Owing to the lack of an appropriate human cardiomyocyte experimental model, current research on AIC is primarily based on clinical case reports. In this study, we generated human iPSC-derived cardiomyocytes (iPSC-CMs) and characterized the cardiotoxicity of 6 antipsychotics (clozapine, haloperidol, quetiapine, olanzapine, risperidone, and aripiprazole) used in clinical practice. Multielectrode array analysis revealed that all 6 antipsychotics, when used within their respective clinical plasma concentration (CPC) ranges, were likely to cause a significantly prolonged field potential duration (FPD) in iPSC-CMs. Moreover, administration of the third-generation antipsychotic aripiprazole (10 mg/kg, i.g.) led to marked QT interval prolongation in beagle dogs. We demonstrated that aripiprazole administration resulted in mitochondrial damage and oxidative stress, which accelerated protein degradation of human ether-à-go-go-related gene (hERG) channels, generating a rapid delayed rectifying potassium current (I_Kr) through the proteasome pathway, ultimately leading to FPD prolongation. Scavenging reactive oxygen species or suppressing the ubiquitin‒proteasome pathway (UPP) significantly restored hERG channel function and rescued the prolonged FPD phenotype in aripiprazole-treated iPSC-CMs. Our results suggest that caution should be taken when aripiprazole is prescribed to high-risk patients with preexisting comorbidities. Manipulation of excessive oxidative stress or suppression of the UPP may offer novel therapeutic strategies for mitigating aripiprazole-induced proarrhythmic risk.

Stroke is the second leading cause of mortality and the leading cause of adult disability worldwide. Neuroinflammation is a crucial mechanism that regulates the pathogenesis and prognosis of stroke and involves both peripheral and intracerebral immune cells. Neutrophils and microglia are the primary immune cells that mediate neuroinflammation and play bidirectional roles after stroke. Significant interactions between neutrophils and microglia exist. Microglia regulate the activation, infiltration, as well as formation of neutrophil extracellular traps (NETs), whereas neutrophils regulate the polarization and phagocytic activity of microglia. In this review, we summarize the bidirectional roles of neutrophils and microglia in stroke with an emphasis on the interactions between neutrophils and microglia, as well as the associated signaling pathways and targets involved. We further introduce potential stroke treatment drugs that regulate the interactions between neutrophils and microglia, including anti-inflammatory drugs and natural products. We propose that, according to the different ischemic times and cell activation states, regulating the interactions between neutrophils and microglia through relevant targets and signaling pathways may be an ideal strategy for the anti-inflammatory treatment of stroke, potentially improving treatment and prognosis of stroke. This review summarizes the bidirectional roles of neutrophils and microglia in stroke, respectively, focusing on the interactions and signaling pathways between neutrophils and microglia, as well as potential therapeutic targets and drugs.

Cerebral ischemia-reperfusion injury (CIRI) represents a significant clinical challenge, with microglial homeostasis playing a critical role in its pathological progression. Venenum bufonis (VB) has been extensively utilized as a cardiotonic, analgesic, and antineoplastic agent in the clinical practice of traditional Chinese medicine. Resibufogenin (RBG) is a bufadienolide compound derived from VB that has a wide range of pharmacological activities, including antitumor, anti-inflammatory, and cardiovascular protective effects. In this study, we investigated the neuroprotective effects of RBG on the progression of CIRI and the underlying mechanisms. A CIRI model was established in rats by transient middle cerebral artery occlusion (tMCAO), after which the rats were administered RBG (2.6 or 4.0 mg·kg^-1·d^-1, i.g.) for 5 days. We showed that RBG administration markedly reduced cerebral infarct volume, restored neurological deficits, and mitigated neuronal loss in tMCAO rats. Quantitative proteomic analysis and robust experimental data revealed that RBG modulated microglial iron homeostasis by altering the binding affinity of the transcription factor Nrf2 to the antioxidant response element (ARE) within the promoter region of transferrin receptor protein 1 (TFR1). In BV2 cells under oxygen-glucose deprivation/reperfusion (OGD/R) conditions, RBG (5, 10, and 20 μM) dose-dependently modulated iron metabolism by increasing the expression of Nrf2 and the downstream antioxidants HO-1, NQO1, GCLC, and GCLM, thus restoring redox homeostasis. We found that RBG activated the Nrf2 signaling pathway by covalently binding to the Cys297 residue of Keap1, which was confirmed by site-directed mutagenesis in BV2 cells. In a BV2-PC12 cell coculture system subjected to OGD/R, RBG (20 μM) effectively alleviated neuronal apoptosis, whereas Nrf2 knockdown in BV2 cells abrogated the neuroprotective effect of RBG. Similarly, inhibition of Nrf2 using ML385 markedly diminished RBG-induced improvements in neurological behavior in tMCAO rats. Our results identify RBG as a new modulator of the Keap1-Nrf2-TFR1/ARE axis and suggest that RBG has promising neuroprotective potential against CIRI through its effects on microglial homeostasis.

Atherosclerosis preferentially develops at arterial bifurcations where the endothelial cells are constantly exposed to disturbed flow, and sustained oscillatory shear stress (OSS) triggers endothelial inflammation. The mechanosensitive transcriptional coactivator YAP plays a critical role in disturbed flow-induced endothelial inflammation. Our recent studies show that disturbed flow upregulates the expression of the mechanosensor 5-HT_1B. In this study, we investigated the molecular mechanisms underlying OSS-induced 5-HT_1B upregulation in vivo and in vitro. Disturbed flow was induced in mice by partial carotid ligation. In vitro experiments were conducted in human aortic endothelial cells (HAECs) subjected to oscillatory shear stress using an ibidi flow system. We showed that oscillatory shear stress significantly upregulated the expression of 5-HT_1B in HAECs via activation of YAP, while knockout of YAP significantly reduced this upregulation. We demonstrated that YAP directly regulated the expression of HTR1B via binding to its promoter region. Inhibition of 5-HT_1B using its antagonist SB-216641 impeded YAP nuclear localization and endothelial activation in HAECs. We verified that a 5-HT_1B-YAP loop was also activated in atherosclerotic arteries of ApoE-/- mice. Endothelium-specific overexpression of YAP exacerbated atherosclerosis. Moreover, endothelium-specific knockout of 5-HT_1B or YAP inhibited disturbed flow-induced endothelial inflammation and plaque formation in ApoE-/- mice. Taken together, the 5-HT_1B-YAP positive feedback loop amplifies the pro-atherogenic effect of disturbed flow. We suggest that targeting 5-HT_1B-YAP loop holds promise as a novel therapeutic strategy for atherosclerotic diseases.

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the development of multiple fluid-filled cysts in the kidneys, resulting in progressive decline and failure of renal function. Microsomal prostaglandin E synthase-2 (mPGES-2) is a unique bifunctional enzyme that catalyzes the conversion of prostaglandin H₂ (PGH₂) to prostaglandin E₂ (PGE₂) or to malondialdehyde (MDA) in conjunction with heme. PGE₂ and MDA are key mediators that regulate cell growth and proliferation, respectively. In this study, we elucidated the functional role of mPGES-2 in ADPKD. By performing Western blot and immunohistochemical staining on the kidneys of patients with PKD and healthy controls, we showed that the expression levels of mPGES-2 markedly increased. We then crossed mPGES-2 knockout (Ptges2^-/-) mice with Ksp-Cre; pkd1^flox/+ mice to generate mPGES-2 knockout ADPKD (Ptges2^-/-; PKD) mice. We showed that mPGES-2 depletion mitigated ADPKD progression in a mouse model. These findings were corroborated by in vitro experiments in embryonic kidney cells: the application of the mPGES-2 inhibitor SZ0232 (40, 80, and 160 μM) effectively suppressed cyst growth, suggesting a potential therapeutic option for ADPKD. Analysis of mPGES-2 metabolites revealed that mPGES-2 deficiency led to a reduction in PGE₂ production, which has not been detected in other renal diseases, likely because of the diminished heme levels in ADPKD kidneys. Moreover, mPGES-2 was implicated in the regulation of the downstream signaling pathway involving β-catenin/STAT3-c-Myc via PGE₂-EP₄, which promoted abnormal proliferation of renal tubular epithelial cells and influenced cyst formation. Our findings suggest that targeting mPGES-2 is a viable therapeutic strategy for the management of ADPKD.

Although most AD-related pathological studies are limited to the brain, increasing evidence has demonstrated the contribution of peripheral immune cells to the pathogenesis of AD. We recently demonstrated that meningeal B cells inhibit β-amyloid (Aβ) production in the frontal cortex of young 5×FAD mice. In this study, we explored the precise origin of meningeal B cells. We observed that the AD-like pathology in 5×FAD mice was exacerbated when the germinal center in the lung lymph nodes was specifically destroyed via the intratracheal instillation of anti-CD40 antibodies, whereas it was alleviated via the intratracheal instillation of AAV-mBAFF to overexpress B-cell activating factor in the lungs. We demonstrated that Aβ was drained from the brain via meningeal lymphatics and eventually traveled to the lungs, where it activated B cells via the TLR4/NF-ĸB signaling pathway, whereas the CXCL12-CXCR4 axis regulated lung B-cell infiltration into the frontal cortex. We revealed that the increased number of B cells in the lungs of 5×FAD mice mainly included memory B (Bmem) cells. The supplementation of lung Bmem cells mitigated AD-like pathology in B-cell-deficient μMT^-/-/5×FAD mice, which was abolished by using a CXCR4 antagonist. The suppression of CXCL12 expression in frontal microglia via AAV-siCXCL12 inhibited the infiltration of CXCR4⁺ Bmem cells and increased the Aβ burden in the frontal cortex of 5×FAD mice. Collectively, our results demonstrate an unexpected protective effect of lung Bmem cells on AD-like pathology.

Breast cancer liver metastasis (BCLM) is characterized by high incidence and poor prognosis, lacking effective therapeutic strategies. Recent evidence suggests that lipid metabolic reprogramming plays an important role in the initiation and development of BC metastasis. In clinical practice of traditional Chinese medicine, Citri Reticulatae Pericarpium-Reynoutria japonica Houtt. (CR) herb pair is used for the treatment of BCLM. In this study, we explored the active ingredients of CR herb pair and underlying mechanisms against BCLM. By RNA sequencing analysis, we showed that extracellular matrix protein 1 isoform a (ECM1a), a secreted multifunctional glycoprotein, was a vital link between liver-metastatic potential and fatty acid (FA)-biosynthesis program in triple-negative breast cancer (TNBC) cells. Through integrative screening approaches, nobiletin and polydatin were identified as the core active ingredients of the CR herb pair. As an ECM1a inhibitor, nobiletin+polydatin combination exerted superior synergistic inhibitory effects on TNBC cells and liver-metastatic xenograft models. We further revealed that nobiletin+polydatin combination impaired ECM1a-mediated tumor FA-biosynthesis program by downregulating PI3K/AKT/mTOR/SREBPs signaling. These results support nobiletin+polydatin combination as a novel and promising therapeutic option for BCLM and highlight the role of ECM1a as the targetable master regulator of lipid metabolism in BCLM.