Cytochrome P450 Inhibitor

Chlorpromazine is an orally active, blood-brain barrier-transparent antipsychotic agent that effectively antagonises D2 dopamine receptors and 5-HT_2A, which is widely used in schizophrenia and other psychiatric disorders. Chlorpromazine exerts anti-cancer activity through a variety of pathways, including anti-proliferation, induction of autophagy and cycle arrest (G2-M phase), inhibition of cytochrome c oxidase (CcO), inhibition of tumour growth and metastasis, and inhibition of tumour immune escape. Chlorpromazine also blocks hNa_v1.7 channels (IC₅₀=25.9 μM; concentration-dependent) and HERG potassium channels (IC₅₀=21.6 μM), which has potential for analgesic and cardiac arrhythmic studies. Chlorpromazine also can inhibit clathrin-mediated endocytosis.

Verapamil ((±)-Verapamil) is a calcium channel blocker and a potent and orally active first-generation P-glycoprotein (P-gp) inhibitor. Verapamil also inhibits CYP3A4. Verapamil has the potential for high blood pressure, heart arrhythmias and angina research.

Fenofibrate is a selective PPARα agonist with an EC₅₀ of 30 μM. Fenofibrate also inhibits human cytochrome P450 isoforms, with IC₅₀s of 0.2, 0.7, 9.7, 4.8 and 142.1 μM for CYP2C19, CYP2B6, CYP2C9, CYP2C8, and CYP3A4, respectively.

Apigenin (4',5,7-Trihydroxyflavone) is a competitive CYP2C9 inhibitor with a K_i of 2 μM.

Letrozole (CGS 20267) is a potent, selective, reversible and orally active non-steroidal inhibitor of aromatase, with an IC₅₀ of 11.5 nM. Letrozole selective inhibits estrogen biosynthesis, and can be used for the research of breast cancer.

Itraconazole (R51211) is a triazole antifungal agent and a potent and orally active Hedgehog (Hh) signaling pathway antagonist with an IC₅₀ of ~800 nM. Itraconazole potently inhibits lanosterol 14α-demethylase (cytochrome P450 enzyme), thereby inhibits the oxidative conversion of lanosterol to ergosterol. Itraconazole has anticancer and antiangiogenic effects. Itraconazole is a oxysterol-binding protein (OSBP) inhibitor.

Stiripentol (STP) is an anticonvulsant agent, which can inhibit N-demethylation of CLB to NCLB mediatated by CYP3A4 (noncompetitively) and CYP2C19 (competitively) with K_i of 1.59±0.07 and 0.516±0.065 μM and IC₅₀ of 1.58 and 3.29 μM, respectively.

Metyrapone (Su-4885) is a potent and orally active 11β-hydroxylase inhibitor and an autophagy activator, also inhibits the production of aldosterone. Metyrapone inhibits synthesis of endogenous adrenal corticosteroid, decreases glucocorticoid levels, and also affects behavior and emotion. In addition, Metyrapone increases the efficiency of autophagic process via downregulation of mTOR pathway, and interacts with Pseudomonas putida cytochrome P-450. Metyrapone can be used for researching Cushing's syndrome and depression.

Verapamil hydrochloride ((±)-Verapamil hydrochloride) is a calcium channel blocker and a potent and orally active first-generation P-glycoprotein (P-gp) inhibitor. Verapamil hydrochloride also inhibits CYP3A4. Verapamil hydrochloride has the potential for high blood pressure, heart arrhythmias and angina research.

Ketoconazole (R-41400) is an imidazole anti-fungal agent, a CYP3A4 and CYP24A1 inhibitor.

1-Aminobenzotriazole is a nonspecific and irreversible inhibitor of cytochrome P450 (P450).

Chlorpromazine hydrochloride is an orally active, blood-brain barrier-transparent antipsychotic agent that effectively antagonises D2 dopamine receptors and 5-HT_2A, which is widely used in schizophrenia and other psychiatric disorders. Chlorpromazine hydrochloride exerts anti-cancer activity through a variety of pathways, including anti-proliferation, induction of autophagy and cycle arrest (G2-M phase), inhibition of cytochrome c oxidase (CcO), inhibition of tumour growth and metastasis, and inhibition of tumour immune escape. Chlorpromazine hydrochloride also blocks hNa_v1.7 channels (IC₅₀=25.9 μM; concentration-dependent) and HERG potassium channels (IC₅₀=21.6 μM), which has potential for analgesic and cardiac arrhythmic studies. Chlorpromazine hydrochloride also can inhibit clathrin-mediated endocytosis.

Abiraterone is a potent and irreversible CYP17A1 inhibitor with antiandrogen activity, which inhibits both the 17α-hydroxylase and 17,20-lyase activity of the cytochrome p450 enzyme CYP17 with IC₅₀s of 2.5 nM and 15 nM, respectively.

Atovaquone (Atavaquone) is a potent, selective and orally active inhibitor of the parasite’s mitochondrial cytochrome bc1 complex. Atovaquone is against human and P. falciparum cytochrome bc1 activity with IC₅₀ values of 460 nM and 2.0 nM, respectively. Atovaquone is an antimalarial agent and has the potential for the investigation of neumocystis pneumonia, toxoplasmosis, malaria, and babesia.

Oleuropein, found in olive leaves and oil, exerts antioxidant, anti-inflammatory and anti-atherogenic effects through direct inhibition of PPARγ transcriptional activity. Oleuropein induces apoptosis in breast cancer cells via the p53-dependent pathway and through the regulation of Bax and Bcl2 genes. Oleuropein also inhibits aromatase.

Naringin is a major flavanone glycoside obtained from tomatoes, grapefruits, and many other citrus fruits. Naringin exhibits biological properties such as antioxidant, anti-inflammatory, and antiapoptotic activities. Naringin also inhibits proliferation and invasion and induces apoptosis in human osteosarcoma cells by inhibiting zinc finger E-box binding homeobox 1 (Zeb1).

Clarithromycin has a broad spectrum of antimicrobial activity. Clarithromycin inhibits the CYP3A4-catalyzed triazolam alpha-hydroxylation with the IC₅₀ (K_i) value of 56 (43) μM. Clarithromycin significantly inhibits the HERG potassium current.Clarithromycin affects the autophagic flux by impairing the signaling pathway linking hERG1 and PI3K.

Hypericin is a naturally occurring substance found in Hyperlcurn perforatum L. Hypericin is an inhibitor of PKC (protein kinase C), MAO (monoaminoxidase), dopamine-beta-hydroxylase, reverse transcriptase, telomerase and CYP (cytochrome P450). Hypericin shows antitumor, antiviral, antidepressive activities, and can induce apoptosis.

Gemfibrozil 1-O-β-Glucuronide, a metabolite of Gemfibrozil (CI-719; HY-B0258), is a potent and competitive P450 (CYP) isoform CYP2C8 inhibitor with an IC₅₀ of 4.07 μM.

Cepharanthine is a natural product that can be isolated from the plant Stephania cephalantha Hayata. Cepharanthine has anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) activities. Cepharanthine has good effective in suppressing viral proliferation (half maximal (50%) inhibitory concentration (IC₅₀) and 90% inhibitory concentration (IC₉₀) values of 1.90 and 4.46 μM. Cepharanthine can also effectively reverses P-gp-mediated multidrug resistance in K562 cells and increase enhances the sensitivity of anticancer agents in xenograft mice model. Cepharanthine shows inhibitory effects of human liver cytochrome P450 enzymes CYP3A4, CYP2E1 and CYP2C9. Cepharanthine has antitumor, anti-inflammatory and antinociceptive effects.