Britannin as a novel NLRP3 inhibitor, suppresses inflammasome activation in macrophages and alleviates NLRP3-related diseases in mice.

Overactivation of the NLRP3 inflammasomes induces production of pro-inflammatory cytokines and drives pathological processes. Pharmacological inhibition of NLRP3 is an explicit strategy for the treatment of inflammatory diseases. Thus far no drug specifically targeting NLRP3 has been approved by the FDA for clinical use. This study was aimed to discover novel NLRP3 inhibitors that could suppress NLRP3-mediated pyroptosis. We screened 95 natural products from our in-house library for their inhibitory activity on IL-1ß secretion in LPS + ATP-challenged BMDMs, found that Britannin exerted the most potent inhibitory effect with an IC50 value of 3.630 µM. We showed that Britannin (1, 5, 10 µM) dose-dependently inhibited secretion of the cleaved Caspase-1 (p20) and the mature IL-1ß, and suppressed NLRP3-mediated pyroptosis in both murine and human macrophages. We demonstrated that Britannin specifically inhibited the activation step of NLRP3 inflammasome in BMDMs via interrupting the assembly step, especially the interaction between NLRP3 and NEK7. We revealed that Britannin directly bound to NLRP3 NACHT domain at Arg335 and Gly271. Moreover, Britannin suppressed NLRP3 activation in an ATPase-independent way, suggesting it as a lead compound for design and development of novel NLRP3 inhibitors. In mouse models of MSU-induced gouty arthritis and LPS-induced acute lung injury (ALI), administration of Britannin (20 mg/kg, i.p.) significantly alleviated NLRP3-mediated inflammation; the therapeutic effects of Britannin were dismissed by NLRP3 knockout. In conclusion, Britannin is an effective natural NLRP3 inhibitor and a potential lead compound for the development of drugs targeting NLRP3.

Clinical and genetic analysis of essential hypertension with mitochondrial tRNAMet 4435A>G and YARS2 mutation. / 携带线粒体tRNAMet 4435A>Gå’Œæ ¸åŸºå› YARS2çªå˜çš„åŽŸå‘æ€§é«˜è¡€åŽ‹å®¶ç³»é—ä¼ å­¦åˆ†æž.

OBJECTIVES: To investigate the role of m.4435A>G and YARS2 c.572G>T (p.G191V) mutations in the development of essential hypertension. METHODS: A hypertensive patient with m.4435A>G and YARS2 p.G191V mutations was identified from previously collected mitochondrial genome and exon sequencing data. Clinical data were collected, and a molecular genetic study was conducted in the proband and his family members. Peripheral venous blood was collected, and immortalized lymphocyte lines constructed. The mitochondrial transfer RNA (tRNA), mitochondrial protein, adenosine triphosphate (ATP), mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) in the constructed lymphocyte cell lines were measured. RESULTS: Mitochondrial genome sequencing showed that all maternal members carried a highly conserved m.4435A>G mutation. The m.4435A>G mutation might affect the secondary structure and folding free energy of mitochondrial tRNA and change its stability, which may influence the anticodon ring structure. Compared with the control group, the cell lines carrying m.4435A>G and YARS2 p.G191V mutations had decreased mitochondrial tRNA homeostasis, mitochondrial protein expression, ATP production and MMP levels, as well as increased ROS levels (all P<0.05). CONCLUSIONS: The YARS2 p.G191V mutation aggravates the changes in mitochondrial translation and mitochondrial function caused by m.4435A>G through affecting the steady-state level of mitochondrial tRNA and further leads to cell dysfunction, indicating that YARS2 p.G191V and m.4435A>G mutations have a synergistic effect in this family and jointly participate in the occurrence and development of essential hypertension.

Design, synthesis and anticancer evaluation of 6,7-disubstituted-4-phenoxyquinoline derivatives bearing 1,8-naphthyridine-3-carboxamide moiety as novel multi-target TKIs.

Giving the fact that the disorders of multiple receptor tyrosine kinases (RTKs) are characteristics of various cancers, we assumed that developing novel multi-target drugs might have an advantage in treating the complex cancers. Taking the multi-target c-Met inhibitor Foretinib as the leading compound, we discovered a novel series of 6,7-disubstituted-4-phenoxyquinoline derivatives bearing 1,8-naphthyridine-3-carboxamide moiety with the help of molecular docking. Among them, the most promising compound 33 showed a prominent activity against Hela (IC50 = 0.21 µM), A549 (IC50 = 0.39 µM), and MCF-7 (IC50 = 0.33 µM), which were 3.28-4.82 times more active than that of Foretinib. Additionally, compound 33 dose dependently induced apoptosis by arresting A549 cells at G1 phase. Enzymatic assays and docking analyses were further confirmed that compound 33 was a multi-target inhibitor with the strong potencies against c-Met (IC50 = 11.77 nM), MEK1 (IC50 = 10.71 nM), and Flt-3 (IC50 = 22.36 nM). In the A549 cells mediated xenograft mouse model, compound 33 inhibited the tumor growth (TGI = 64%) without obvious toxicity, establishing compound 33 as a promising candidate for cancer therapy.

Effect of Dimethoate on the Activity of Hepatic CYP450 Based on Pharmacokinetics of Probe Drugs.

BACKGROUND: Dimethoate (DM), one of the most widely used systemic organophosphate insecticide, has been reported to exert toxic effects after long-time subchronic exposure. This study aims at investigating the toxic effect of DM on liver after repeated administration of low doses of DM in rats. METHODS: Twenty Sprague-Dawley rats were randomly divided into the control group (n = 10) and the DM group (n = 10). After 2 weeks' exposure to DM at low dosage (5 mg/kg), biochemical parameters of hepatic functions were measured, histology and CYP450 expressed in liver was detected. The activities of CYP1A2, CYP2C11, CYP2D1, and CYP3A2 were evaluated by the Cocktail method. RESULTS: The level of AChE (acetylcholinesterase) was significantly decreased, hepatic functions were damaged and the mRNA level of CYP2D1 was significantly increased in the DM group (p < 0.05). The pharmacokinetics of probe drug revealed AUC(0-t), AUC(0-∞), t1/2 and Cmax of metoprolol was shorten in the DM group (p < 0.05). However, there were no statistical differences in MRT, t1/2, CL and Tmax for phenacetin, tolbutamide and midazolam. CONCLUSIONS: A low dosage of DM could induce the activity of CYP2D1 in liver and increase the metabolism of metoprolol when exposed for 2 weeks.

OTUD1 Deficiency Alleviates LPS-Induced Acute Lung Injury in Mice by Reducing Inflammatory Response.

The ovarian tumor (OTU) family consists of deubiquitinating enzymes thought to play a crucial role in immunity. Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) pose substantial clinical challenges due to severe respiratory complications and high mortality resulting from uncontrolled inflammation. Despite this, no study has explored the potential link between the OTU family and ALI/ARDS. Using publicly available high-throughput data, 14 OTUs were screened in a simulating bacteria- or LPS-induced ALI model. Subsequently, gene knockout mice and transcriptome sequencing were employed to explore the roles and mechanisms of the selected OTUs in ALI. Our screen identified OTUD1 in the OTU family as a deubiquitinase highly related to ALI. In the LPS-induced ALI model, deficiency of OTUD1 significantly ameliorated pulmonary edema, reduced permeability damage, and decreased lung immunocyte infiltration. Furthermore, RNA-seq analysis revealed that OTUD1 deficiency inhibited key pathways, including the IFN-γ/STAT1 and TNF-α/NF-κB axes, ultimately mitigating the severity of immune responses in ALI. In summary, our study highlights OTUD1 as a critical immunomodulatory factor in acute inflammation. These findings suggest that targeting OTUD1 could hold promise for the development of novel treatments against ALI/ARDS.

Patchouli Alcohol Protects the Heart against Diabetes-Related Cardiomyopathy through the JAK2/STAT3 Signaling Pathway.

Diabetic cardiomyopathy (DCM) represents a common pathological state brought about by diabetes mellitus (DM). Patchouli alcohol (PatA) is known for its diverse advantageous effects, notably its anti-inflammatory properties and protective role against metabolic disorders. Despite this, the influence of PatA on DCM remains relatively unexplored. To explore the effect of PatA on diabetes-induced cardiac injury and dysfunction in mice, streptozotocin (STZ) was used to mimic type 1 diabetes in mice. Serological markers and echocardiography show that PatA treatment protects the heart against cardiomyopathy by controlling myocardial fibrosis but not by reducing hyperglycemia in diabetic mice. Discovery Studio 2017 software was used to perform reverse target screening of PatA, and we found that JAK2 may be a potential target of PatA. RNA-seq analysis of heart tissues revealed that PatA activity in the myocardium was primarily associated with the inflammatory fibrosis through the Janus tyrosine kinase 2 (JAK2)/signal transducer and activator of the transcription 3 (STAT3) pathway. In vitro, we also found that PatA alleviates high glucose (HG) + palmitic acid (PA)-induced fibrotic and inflammatory responses via inhibiting the JAK2/STAT3 signaling pathway in H9C2 cells. Our findings illustrate that PatA mitigates the effects of HG + PA- or STZ-induced cardiomyopathy by acting on the JAK2/STAT3 signaling pathway. These insights indicate that PatA could potentially serve as a therapeutic agent for DCM treatment.

OTUD1 promotes isoprenaline- and myocardial infarction-induced heart failure by targeting PDE5A in cardiomyocytes.

Heart failure represents a major cause of death worldwide. Recent research has emphasized the potential role of protein ubiquitination/deubiquitination protein modification in cardiac pathology. Here, we investigate the role of the ovarian tumor deubiquitinase 1 (OTUD1) in isoprenaline (ISO)- and myocardial infarction (MI)-induced heart failure and its molecular mechanism. OTUD1 protein levels were raised markedly in murine cardiomyocytes after MI and ISO treatment. OTUD1 deficiency attenuated myocardial hypertrophy and cardiac dysfunction induced by ISO infusion or MI operation. In vitro, OTUD1 knockdown in neonatal rat ventricular myocytes (NRVMs) attenuated ISO-induced injuries, while OTUD1 overexpression aggravated the pathological changes. Mechanistically, LC-MS/MS and Co-IP studies showed that OTUD1 bound directly to the GAF1 and PDEase domains of PDE5A. OTUD1 was found to reverse K48 ubiquitin chain in PDE5A through cysteine at position 320 of OTUD1, preventing its proteasomal degradation. PDE5A could inactivates the cGMP-PKG-SERCA2a signaling axis which dysregulate the calcium handling in cardiomyocytes, and leading to the cardiomyocyte injuries. In conclusion, OTUD1 promotes heart failure by deubiquitinating and stabilizing PDE5A in cardiomyocytes. These findings have identified PDE5A as a new target of OTUD1 and emphasize the potential of OTUD1 as a target for treating heart failure.

Carnosol attenuates angiotensin II-induced cardiac remodeling and inflammation via directly binding to p38 and inhibiting p38 activation.

Chronic inflammation is a significant contributor to hypertensive heart failure. Carnosol (Car), primarily derived from the sage plant (Salvia carnosa), exhibits anti-inflammatory properties in a range of systems. Nevertheless, the influence of angiotensin II (Ang II) on cardiac remodeling remains uncharted. Car was shown to protect mice's hearts against Ang II-induced heart damage at dosages of 20 and 40 mg/kg/d. This protection was evident in a concentration-related decrease in the remodeling of the heart and dysfunction. Examination of the transcriptome revealed that the pivotal roles in mediating the protective effects of Car involved inhibiting Ang II-induced inflammation and the activation of the mitogen-activated protein kinase (MAPK) pathway. Furthermore, Car was found to inhibit p38 phosphorylation, therefore reducing the level of inflammation in cultured cardiomyocytes and mouse hearts. This effect was attributed to the direct binding to p38 and inhibition of p38 protein phosphorylation by Car both in vitro and in vivo. In addition, the effects of Car on inflammation were neutralized when p38 was blocked in cardiomyocytes.

Schisandrin B protects against LPS-induced inflammatory lung injury by targeting MyD88.

BACKGROUND: Acute lung injury (ALI) is a challenging clinical syndrome that manifests as an acute inflammatory response. Schisandrin B (Sch B), a bioactive lignan from Schisandra genus plants, has been shown to suppress inflammatory responses and oxidative stress. However, the underlying molecular mechanisms have remained elusive. HYPOTHESIS/PURPOSE: This study performed an in-depth investigation of the anti-inflammatory mechanism of Sch B in macrophages and in an animal model of ALI. METHODS: qPCR array was used to probe the differential effects and potential target of Sch B. ALI was induced by intratracheal administration of LPS in experimental mice with or without Sch B treatment. RESULTS: Our studies show that Sch B differentially modulates inflammatory factor induction by LPS in macrophages by directly binding myeloid differentiation response factor-88 (MyD88), an essential adaptor protein in the toll-like receptor-4 (TLR4) pathway. Sch B spares non-MyD88-pathways downstream of TLR4. Such inhibition suppressed key signaling mediators such as TAK1, MAPKs, and NF-κB, and pro-inflammatory factor induction. Pull down assay using biotinylated-Sch B validate the direct interaction between Sch B and MyD88 in macrophages. Treatment of mice with Sch B prior to LPS challenge reduced inflammatory cell infiltration in lungs, induction of MyD88-pathway signaling proteins, and prevented inflammatory cytokine induction. CONCLUSION: In summary, our studies have identified MyD88 as a direct target of Sch B for its anti-inflammatory activity, and suggest that Sch B may have therapeutic value for acute lung injury and other MyD88-dependent inflammatory diseases.

Ang II (Angiotensin II)-Induced FGFR1 (Fibroblast Growth Factor Receptor 1) Activation in Tubular Epithelial Cells Promotes Hypertensive Kidney Fibrosis and Injury.

BACKGROUND: Elevated Ang II (angiotensin II) level leads to a range of conditions, including hypertensive kidney disease. Recent evidences indicate that FGFR1 (fibroblast growth factor receptor 1) signaling may be involved in kidney injuries. In this study, we determined whether Ang II alters FGFR1 signaling to mediate renal dysfunction. METHODS: Human archival kidney samples from patients with or without hypertension were examined. Multiple genetic and pharmacological approaches were used to investigate FGFR1-mediated signaling in tubular epithelial NRK-52E cells in response to Ang II stimulation. C57BL/6 mice were infused with Ang II for 28 days to develop hypertensive kidney disease. Mice were treated with either adeno-associated virus expressing FGFR1 shRNA or FGFR1 inhibitor AZD4547. RESULTS: Kidney specimens from subjects with hypertension and mice challenged with Ang II have increased FGFR1 activity in renal epithelial cells. Renal epithelial cells in culture initiate extracellular matrix programming in response to Ang II, through the activation of FGFR1, which is independent of both AT1R (angiotensin II receptor type 1) and AT2R (angiotensin II receptor type 2). The RNA sequencing analysis indicated that disrupting FGFR1 suppresses Ang II-induced fibrogenic responses in epithelial cells. Mechanistically, Ang II-activated FGFR1 leads to STAT3 (signal transducer and activator of transcription 3) activation, which is responsible for fibrogenic factor expression in kidneys. In the mouse model of hypertensive kidney disease, genetic knockdown of FGFR1 or pharmacological inhibition of its activity protected kidneys from dysfunction and fibrosis upon Ang II challenge. CONCLUSIONS: Our studies uncover a novel mechanism causing renal fibrosis in hypertension and indicate FGFR1 as a potential target to preserve renal function and integrity.

Bicyclol ameliorates nonalcoholic fatty liver disease in mice via inhibiting MAPKs and NF-κB signaling pathways.

Bicyclol has been approved as an anti-inflammatory, hepatoprotective drug in China to treat various forms of hepatitis. However, the role of bicyclol in non-alcoholic fatty liver disease (NAFLD) is unknown. In this study, NAFLD model was established by feeding mice with high fat diet (HFD) for 16 weeks, and bicyclol (25 and 50 mg/kg) were orally administered for the last 4 weeks. Although bicyclol treatment did not change the body weight of mice, bicyclol administration significantly improved HFD-induced dyslipidemia, NAFLD activity score, hepatic apoptosis, systemic and hepatic inflammation, and liver fibrosis in the mice. Moreover, bicyclol treatment significantly inhibited HFD-induced activation of MAPKs and NF-κB signaling pathways that may mediate the inflammatory responses. Further in vitro studies showed that bicyclol pretreatment markedly ameliorated PA-induced inflammatory responses in human hepatocyte HL-7702 cells and mouse peritoneal macrophages through inhibiting MAPKs and NF-κB signaling pathways. These data indicated that bicyclol may have the potency to treat NAFLD by reducing inflammation.

Inhibition of CDK9 attenuates atherosclerosis by inhibiting inflammation and phenotypic switching of vascular smooth muscle cells.

BACKGROUND: Recent studies have demonstrated a key role of vascular smooth muscle cell (VSMC) dysfunction in atherosclerosis. Cyclin-dependent kinases 9 (CDK9), a potential biomarker of atherosclerosis, was significantly increased in coronary artery disease patient serum and played an important role in inflammatory diseases. This study was to explore the pharmacological role of CDK9 inhibition in attenuating atherosclerosis. METHODS: A small-molecule CDK9 inhibitor, LDC000067, was utilized to treat the high fat diet (HFD)-fed ApoE-/- mice and human VSMCs. RESULTS: The results showed that inflammation and phenotypic switching of VSMCs were observed in HFD-induced atherosclerosis in ApoE-/- mice, which were accompanied with increased CDK9 in the serum and atherosclerotic lesions where it colocalized with VSMCs. LDC000067 treatment significantly suppressed HFD-induced inflammation, proliferation and phenotypic switching of VSMCs, resulting in reduced atherosclerosis in the ApoE-/- mice, while had no effect on plasma lipids. Further in vitro studies confirmed that LDC000067 and siRNA-mediated CDK9 knockdown reversed ox-LDL-induced inflammation and phenotypic switching of VSMCs from a contractile phenotype to a synthetic phenotype via inhibiting NF-κB signaling pathway in human VSMCs. CONCLUSION: These results indicate that inhibition of CDK9 may be a novel therapeutic target for the prevention of atherosclerosis.

Curcumin analogue C66 attenuates obesity-induced myocardial injury by inhibiting JNK-mediated inflammation.

Obesity has been recognized as a major risk factor for the development of chronic cardiomyopathy, which is associated with increased cardiac inflammation, fibrosis, and apoptosis. We previously developed an anti-inflammatory compound C66, which prevented inflammatory diabetic complications via targeting JNK. In the present study, we have tested the hypothesis that C66 could prevent obesity-induced cardiomyopathy by suppressing JNK-mediated inflammation. High-fat diet (HFD)-induced obesity mouse model and palmitic acid (PA)-challenged H9c2 cells were used to develop inflammatory cardiomyopathy and evaluate the protective effects of C66. Our data demonstrate a protective effect of C66 against obesity-induced cardiac inflammation, cardiac hypertrophy, fibrosis, and dysfunction, overall providing cardio-protection. C66 administration attenuates HFD-induced myocardial inflammation by inhibiting NF-κB and JNK activation in mouse hearts. In vitro, C66 prevents PA-induced myocardial injury and apoptosis in H9c2 cells, accompanied with inhibition against PA-induced JNK/NF-κB activation and inflammation. The protective effect of C66 is attributed to its potential to inhibit JNK activation, which led to reduced pro-inflammatory cytokine production and reduced apoptosis in cardiomyocytes both in vitro and in vivo. In summary, C66 provides significant protection against obesity-induced cardiac dysfunction, mainly by inhibiting JNK activation and JNK-mediated inflammation. Our data indicate that inhibition of JNK is able to provide significant protection against obesity-induced cardiac dysfunction.

Metabolism of liver CYP450 and ultrastructural changes after long-term administration of aspirin and ibuprofen.

Worldwide, aspirin and ibuprofen are the most commonly used non-steroidal anti-inflammatory drugs (NSAIDs). Some adverse reactions, including gastrointestinal reactions, have been concerned extensively. Nevertheless, the mechanism of liver injury remains unclear. In the present study, we focused on the metabolism of liver cytochrome P450 (CYP450) and ultrastructural morphology of liver cells. A total of thirty rats were divided into three groups of 10. Rats in the aspirin and ibuprofen groups were given enteric-coated aspirin (15 mg/kg) and ibuprofen (15 mg/kg), respectively by gavage for four weeks. The body weights were recorded every two days. Liver function and metabolic capacity of CYP450 were studied on days 14 and 28. We then conducted ultrastructural examinations. Body weights in the Ibuprofen group were lower than those of the Control group, and ALT and AST levels were significantly higher (P < 0.05). There were no significant differences in terms of body weight, ALT or AST between the Aspirin and Control groups. The metabolic capacity of CYP450 was evaluated using five probe drugs, phenacetin, tolbutamide, metoprolol, midazolam, and bupropion. We found that ibuprofen and aspirin induced metabolism of the probe drugs. Moreover, according to the pharmacokinetic data, the Control, Aspirin and Ibuprofen groups could be discriminated accurately. Ultrastructural examination showed that the number of mitochondria was increased in both the Ibuprofen and Aspirin groups. Long-term administration of enteric-coated aspirin and ibuprofen induced the metabolic activity of the CYP450 enzyme. Aspirin had better tolerability than did ibuprofen, as reflected by pharmacokinetic data of probe drug metabolism.