Ezetimibe prevents IL-1β-induced inflammatory reaction in mouse chondrocytes via modulating NF-κB and Nrf2/HO-1 signaling crosstalk

Background: Osteoarthritis, a type of age-related, chronic, degenerative joint disease. Ezetimibe, a cholesterol absorption inhibitor, is widely used for the treatment of various diseases. The role of ezetimibe in osteoarthritis remains unclear. Objective: This study aimed to explored the anti-inflammation effect of ezetimibe on mouse chondrocytes. Method: In the present study, ELISA, qPCR and western blot analysis were performed to evaluate the anti-inflammatory effects of ezetimibe. In addition, enzymes that are highly associated with the anabolism and catabolism of the extracellular matrix of the articular cartilage were also evaluated. Results: Treatment with ezetimibe attenuated the IL-1β-induced degradation of the extracellular matrix, including aggrecan and collagen II. Ezetimibe also attenuated the IL-1β-induced expression levels of MMP3, MMP13 and ADAMTS5, thus exerting protective effects against IL-1β-induced extracellular matrix degradation. The complex mechanism of the anti-inflammatory reaction contributed to the activation of the Nrf2/HO-1 pathway and the suppression of the NF-κB pathway. Conclusion: On the whole, the present study demonstrates that ezetimibe may be a promising agent for further osteoarthritis therapy

Pharmacokinetic Study of Oral 14C-Radiolabeled Hyzetimibe, A New Cholesterol Absorption Inhibitor

Background and objectives: Hyzetimibe is a candidate drug being investigated as the second-in-class cholesterol absorption inhibitor; it lowers plasma levels of low-density lipoprotein cholesterol (LDL-C) by blocking the Niemann-Pick C1-like 1 protein, a transporter mainly expressed in the intestine that allows dietary cholesterol to enter the body from the intestinal lumen. Previous studies on the metabolism of hyzetimibe in healthy volunteers were not enough to show the biotransformation and excretion pathway; in particular, whether hyzetimibe maintains pharmacological action for duration sufficient to pass through the hepatic-intestinal circulation remains unknown. Furthermore, it remains unclear whether the differences between the chemical structures of ezetimibe and hyzetimibe would result in different pharmacokinetic characteristics. Given that the molecular target is in the intestine and the substantial hepatic-intestinal circulation is a metabolic characteristic of the drug, a study of hyzetimibe as an oral 14C-radiolabeled drug, compared with routinely metabolized drugs, would play an important role in uncovering pharmacokinetic details.Methods: After an overnight fast and before taking medication, six healthy male volunteers swallowed an investigational product suspension containing 20 mg/∼100 μCi of 14C-labeled hyzetimibe as a single dose. Whole-blood, plasma, urine, and fecal samples were collected, and hyzetimibe and its metabolites were measured. Pharmacokinetic variables of hyzetimibe and its metabolites were calculated and statistically analyzed according to obtained concentration data. Safety data were collected throughout the study.Results: The major metabolite detected in plasma was hyzetimibe-glucuronide, which accounted for 97.2% of the total plasma radioactivity. The mean cumulative excretion of total radioactivity of the dose was 16.39% in urine and 76.90% in feces. Unchanged drug and hyzetimibe-glucuronide were identified as the major components in the feces and the urine, respectively. The main metabolic conversions of hyzetimibe were glucuronidation (M1), mono-oxidation (M4), and mono-oxidation with additional sulfonation (M7). Hyzetimibe was considered generally safe and well tolerated.Conclusion: This study of 14C-radiolabeled hyzetimibe provides a full profile of the biotransformation and excretion routes of hyzetimibe to improve the understanding of the pharmacokinetic characteristics of hyzetimibe. The changed hydroxyl group in the hyzetimibe structure made it easier for that drug, compared with ezetimibe, to combine with glucuronic acid and subsequently increased the urinary excretion of hyzetimibe vs. ezetimibe. These differences highlight the need to investigate in more detail the different pharmacokinetic impacts on the efficacy and safety of hyzetimibe and ezetimibe.

Ezetimibe and Improving Cardiovascular Outcomes: Current Evidence and Perspectives

Low-density lipoprotein lowering with statins has convincingly and consistently proven to reduce cardiovascular events in both primary and secondary prevention. However, despite high-dose statin therapy, residual cardiovascular risk remains and many patients also do not tolerate statins. Ezetimibe was initially projected as a frontline alternative to statin. It is an intestinal cholesterol absorption inhibitor with modest LDL lowering effects. But, major studies failed to demonstrate any beneficial effect of CV outcomes, and the drug was relegated to oblivion. IMPROVE-IT, a contemporary, large, and well-designed trial, unequivocally demonstrated reduction in CV outcomes with ezetimibe when added to statin therapy. The benefits are seen in both sexes, elderly, CKD, diabetes mellitus, and in patients with prior CABG. It also reduces biomarkers and induces plaque regression like statins. The drug has now established itself as an add-on therapy to statin when monotherapy fails to achieve LDL goals and when it is not tolerated. The combination therapy has excellent safety and efficacy record. It has now been endorsed by major guidelines too in management of dyslipidemia. Yes, ezetimibe can indeed improve cardiovascular outcomes!

Ezetimibe Prevents Ischemia/Reperfusion-Induced Oxidative Stress and Up-Regulates Nrf2/ARE and UPR Signaling Pathways

Background: While reperfusion is crucial for survival after an episode of ischemia, it also causes oxidative stress. Nuclear factor-E2-related factor 2 (Nrf2) and unfolded protein response (UPR) are protective against oxidative stress and endoplasmic reticulum (ER) stress. Ezetimibe, a cholesterol absorption inhibitor, has been shown to activate the AMP-activated protein kinase (AMPK)/Nrf2 pathway. In this study we evaluated whether Ezetimibe affects oxidative stress and Nrf2 and UPR gene expression in cellular models of ischemia-reperfusion (IR). Methods: Cultured cells were subjected to simulated IR with or without Ezetimibe. Results: IR significantly increased reactive oxygen species (ROS) production and the percentage of apoptotic cells without the up-regulation of Nrf2, of the related antioxidant response element (ARE) gene expression or of the pro-survival UPR activating transcription factor 6 (ATF6) gene, whereas it significantly increased the pro-apoptotic CCAAT-enhancer-binding protein homologous protein (CHOP). Ezetimibe significantly decreased the cellular ROS formation and apoptosis induced by IR. These effects were paralleled by the up-regulation of Nrf2/ARE and ATF6 gene expression and by a down-regulation of CHOP. We also found that Nrf2 activation was dependent on AMPK, since Compound C, a pan inhibitor of p-AMPK, blunted the activation of Nrf2. Conclusions: Ezetimibe counteracts IR-induced oxidative stress and induces Nrf2 and UPR pathway activation.

Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe

An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium–hydride complex (Rh–H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor.

Korszerű lipidcsökkentő kezelés

Considerable evidence suggests that “the lower the better” is a reasonable approach for reducing cardiovascular risk by lowering LDL cholesterol levels. Despite the reduction in cardiovascular events and mortality achieved by statin therapy, significant residual risk remains, especially in severe hereditary hypercholesterolemia, such as familial hypercholesterolemia. Some new strategies to achieve even lower LDL levels are now available, including the addition of cholesterol absorption inhibitor ezetimibe, and the recently available Proprotein convertase subtilisin/kexin type 9 monoclonal antibodies. In addition, new LDL drugs may be effectively administrated in those individuals who are unable to tolerate statins. The authors summarize the efficacy and clinical indications of these new agents and review the currently available guidelines. Orv. Hetil., 2016, 157(31), 1219–1223.