Paeonol pharmacokinetics in the rat following i.m. administration

Paeonol repurposing for cancer therapy: From mechanism to clinical translation

Paeonol (PAE) is a natural phenolic monomer isolated from the root bark of Paeonia suffruticosa that has been widely used in the clinical treatment of some inflammatory-related diseases and cardiovascular diseases. Much preclinical evidence has demonstrated that PAE not only exhibits a broad spectrum of anticancer effects by inhibiting cell proliferation, invasion and migration and inducing cell apoptosis and cycle arrest through multiple molecular pathways, but also shows excellent performance in improving cancer drug sensitivity, reversing chemoresistance and reducing the toxic side effects of anticancer drugs. However, studies indicate that PAE has the characteristics of poor stability, low bioavailability and short half-life, which makes the effective dose of PAE in many cancers usually high and greatly limits its clinical translation. Fortunately, nanomaterials and derivatives are being developed to ameliorate PAE's shortcomings. This review aims to systematically cover the anticancer advances of PAE in pharmacology, pharmacokinetics, nano delivery systems and derivatives, to provide researchers with the latest and comprehensive information, and to point out the limitations of current studies and areas that need to be strengthened in future studies. We believe this work will be beneficial for further exploration and repurposing of this natural compound as a new clinical anticancer drug.

Pharmacological effects and mechanisms of paeonol on antitumor and prevention of side effects of cancer therapy

Cancer represents one of the leading causes of mortality worldwide. Conventional clinical treatments include radiation therapy, chemotherapy, immunotherapy, and targeted therapy. However, these treatments have inherent limitations, such as multidrug resistance and the induction of short- and long-term multiple organ damage, ultimately leading to a significant decrease in cancer survivors' quality of life and life expectancy. Paeonol, a nature active compound derived from the root bark of the medicinal plant Paeonia suffruticosa, exhibits various pharmacological activities. Extensive research has demonstrated that paeonol exhibits substantial anticancer effects in various cancer, both in vitro and in vivo. Its underlying mechanisms involve the induction of apoptosis, the inhibition of cell proliferation, invasion and migration, angiogenesis, cell cycle arrest, autophagy, regulating tumor immunity and enhanced radiosensitivity, as well as the modulation of multiple signaling pathways, such as the PI3K/AKT and NF-κB signaling pathways. Additionally, paeonol can prevent adverse effects on the heart, liver, and kidneys induced by anticancer therapy. Despite numerous studies exploring paeonol's therapeutic potential in cancer, no specific reviews have been conducted. Therefore, this review provides a systematic summary and analysis of paeonol's anticancer effects, prevention of side effects, and the underlying mechanisms involved. This review aims to establish a theoretical basis for the adjunctive strategy of paeonol in cancer treatment, ultimately improving the survival rate and enhancing the quality of life for cancer patients.

Cardioprotective Effect of Paeonol on Chronic Heart Failure Induced by Doxorubicin via Regulating the miR-21-5p/S-Phase Kinase-Associated Protein 2 Axis

Background

This study primarily explored the role of paeonol in doxorubicin (DOX)-induced chronic heart failure (CHF), considering the cardioprotective effect of paeonol on an epirubicin-induced cardiac injury.

Methods

DOX-induced CHF-modeled rats were treated with paeonol. Cardiac function and myocardial damage in rats were evaluated by using the multifunction instrument, and the histopathology, apoptosis, and the expression of miR-21-5p and S-phase kinase-associated protein 2 (SKP2) in myocardium were detected. The target gene of miR-21-5p was confirmed by a dual-luciferase reporter assay. After the required transfection or paeonol treatment, the viability, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) of the DOX-induced cardiomyocytes were determined. Reverse-transcription quantitative-PCR (RT-qPCR) and Western blot were performed to quantify the expressions of miR-21-5p, SKP2, and apoptosis-related factors.

Results

Paeonol improved cardiac function and also ameliorated the cardiac damage of CHF-modeled rats, where the downregulation of abnormally elevated myocardial damage markers, including brain natriuretic peptide, lactate dehydrogenase, renin, angiotensin II, aldosterone, and endothelin 1, was observed. Paeonol alleviated the histopathological injury and suppressed the apoptosis in CHF-modeled rats, inhibited miR-21-5p expression, and upregulated SKP2 expression in vitro and in vivo. miR-21-5p targeted SKP2. Paeonol and SKP2 increased the viability and MMP, but reduced apoptosis and ROS in the DOX-induced cardiomyocytes. miR-21-5p exerted effects opposite to PAE and SKP2, and it downregulated the expression of Bcl-2 and mitochondrion-Cytochrome c (Cyt c) and upregulated the expression of Bax, C-caspase-3, and cytoplasm-Cyt c. miR-21-5p reversed the effects of paeonol, and its effects were further reversed by SKP2.

Conclusion

Paeonol shows a cardioprotective effect on DOX-induced CHF via regulating the miR-21-5p/SKP2 axis.

Paeonol for the Treatment of Atherosclerotic Cardiovascular Disease: A Pharmacological and Mechanistic Overview

With improvement in living standards and average life expectancy, atherosclerotic cardiovascular disease incidences and mortality have been increasing annually. Paeonia suffruticosa, a natural herb, has been used for the treatment of atherosclerotic cardiovascular disease for thousands of years in Eastern countries. Paeonol is an active ingredient extracted from Paeonia suffruticosa. Previous studies have extensively explored the clinical benefits of paeonol. However, comprehensive reviews on the cardiovascular protective effects of paeonol have not been conducted. The current review summarizes studies reporting on the protective effects of paeonol on the cardiovascular system. This study includes studies published in the last 10 years. The biological characteristics of Paeonia suffruticosa, pharmacological mechanisms of paeonol, and its toxicological and pharmacokinetic characteristics were explored. The findings of this study show that paeonol confers protection against atherosclerotic cardiovascular disease through various mechanisms, including inflammation, platelet aggregation, lipid metabolism, mitochondria damage, endoplasmic reticulum stress, autophagy, and non-coding RNA. Further studies should be conducted to elucidate the cardiovascular benefits of paeonol.

Effects of Paeonol and Gastroretention Tablets of Paeonol on Experimental Gastric Ulcers and Intestinal Flora in Rats

Paeonol, a major ingredient isolated from Moutan Cort, has various pharmacological effects. Our previous studies have shown that paeonol can exert antioxidant and anti-inflammatory therapeutic effects on ethanol-induced experimental gastric ulcer (GU). Therefore, in this study, we designed two GU models in rats induced by pyloric ligation (PL) and acetic acid and evaluated the protective effects of paeonol and gastroretention tablets of paeonol (GRT-Ps; 24, 48, and 96 mg/kg) on GU in rats and the effect of paeonol (48 mg/kg) on the intestinal flora. In vivo experiments showed that paeonol or GRT-Ps remarkably reduced gastric mucosal damage in a dose-dependent manner in the different types of models and improved the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content. And in fact, the sustained-release effect of GRT-Ps is more conducive to the improvement of GU compared with the rapid clearance of free drugs. In the PL-induced model, gastric secretion parameters, that is, pH and total acid, showed significant differences compared with the model group. In addition, paeonol treatment can improve the richness and diversity of the intestinal flora and increase the amount of beneficial bacteria, such as Lactobacillus. Paeonol and its stable sustained-release tablet GRT-Ps can promote ulcer healing by inhibiting oxidative stress and regulating the intestinal flora. This study can provide basis for the clinical treatment of GU with paeonol. Graphical Abstract.

Beneficial Effects Exerted by Paeonol in the Management of Atherosclerosis

Atherosclerosis, a chronic luminal stenosis disorder occurred in large and medium arteries, is the principle pathological basis of cardiovascular diseases with the highest morbidity and mortality worldwide. In oriental countries, traditional Chinese medicine Cortex Moutan has been widely used for the treatment of atherosclerosis-related illnesses for thousands of years. Paeonol, a bioactive monomer extracted from Cortex Moutan, is an important pharmacological component responsible for the antiatherosclerotic effects. Numerous lines of findings have established that paeonol offers beneficial roles against the initiation and progression of atherosclerotic lesions through inhibiting proatherogenic processes, such as endothelium damage, chronic inflammation, disturbance of lipid metabolism, uncontrolled oxidative stress, excessive growth, and mobilization of vascular smooth muscle cells as well as abnormality of platelet activation. Investigations identifying the atheroprotective effects of paeonol present substantial evidence for potential clinical application of paeonol as a therapeutic agent in atherosclerosis management. In this review, we summarize the antiatherosclerotic actions by which paeonol suppresses atherogenesis and provide newly insights into its atheroprotective mechanisms and the future clinical practice.