Direct radical scavenging by the bisbenzylisoquinoline alkaloid cepharanthine

Ferroptosis as a Therapeutic Target in Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a cerebrovascular disorder with significant mortality and morbidity. Neural injury in SAH is mediated through a variety of pathophysiological processes. Currently available treatments are either nonspecific in targeting the basic pathophysiological mechanisms that result in neural damage in SAH, or merely focus on vasospasm. Ferroptosis is a type of programmed iron dependent cell death, which has received attention due to its possible role in neural injury in SAH. Herein, we review how intracellular iron overload mediates the production of reactive free radicals and lipid peroxidation through a variety of biochemical pathways in SAH. This in turn results in induction of ferroptosis, as well as exacerbation of vasospasm. We also discuss several therapeutic agents that have been shown to inhibit ferroptosis through targeting different steps of the process. Such agents have proven effective in ameliorating vasospasm, neural damage, and neurobehavioral outcomes in animal models of SAH. Human studies to test the safety and efficacy of intrathecal or parenteral administration of the inhibitors of ferroptosis in improving outcomes of SAH patients are warranted. There are currently a few ongoing clinical trials pursuing this therapeutic concept, the results of which will be critical to determine the value of ferroptosis as a novel therapeutic target in SAH.

Pharmacological Activity of Cepharanthine

Cepharanthine, a natural bisbenzylisoquinoline (BBIQ) alkaloid isolated from the plant Stephania Cephalantha Hayata, is the only bisbenzylisoquinoline alkaloid approved for human use and has been used in the clinic for more than 70 years. Cepharanthine has a variety of medicinal properties, including signaling pathway inhibitory activities, immunomodulatory activities, and antiviral activities. Recently, cepharanthine has been confirmed to greatly inhibit SARS-CoV-2 infection. Therefore, we aimed to describe the pharmacological properties and mechanisms of cepharanthine, mainly including antitumor, anti-inflammatory, anti-pathogen activities, inhibition of bone resorption, treatment of alopecia, treatment of snake bite, and other activities. At the same time, we analyzed and summarized the potential antiviral mechanism of cepharanthine and concluded that one of the most important anti-viral mechanisms of cepharanthine may be the stability of plasma membrane fluidity. Additionally, we explained its safety and bioavailability, which provides evidence for cepharanthine as a potential drug for the treatment of a variety of diseases. Finally, we further discuss the potential new clinical applications of cepharanthine and provide direction for its future development.

Effect of Cepharanthine on the Stemness of Lung Squamous Cell Carcinoma Based on Network Pharmacology and Bioinformatics

Background

Lung squamous cell carcinoma (LUSC) has poor survival prognosis and few clinical treatment options. We urgently need to explore new therapeutic drugs in clinical practice. Cepharanthine (CEP) has been shown to have anticancer effects in several tumors, but the mechanism of CEP in treating LUSC has not been reported.

Methods

SwissTargetPrediction, PharmMapper, and GeneCards were used to identify targets of CEP and LUSC. Further topological analysis was used to obtain hub genes via Cytoscape. Molecular docking was carried out to verify the combination of CEP with hub targets. Based on bioinformatics, we first analyzed the expression and survival of hub targets in LUSC and further analyzed the correlation between hub targets and cancer stemness, immune cell infiltration, and tumor mutation burden (TMB).

Results

A total of 41 targets were identified. Further topological analysis identified 6 hub genes: AURKA, CCNA2, CCNE1, CDK1, CHEK1, and PLK1. Molecular docking analysis showed that CEP had stable binding to all these 6 target proteins. In-depth bioinformatics analysis of these 6 targets showed that high expression of these targets were positively correlated with cancer stemness index and negatively correlated with tumor infiltrating immune cells. In immune subtype analysis, the expressions of these targets were significantly decreased in inflammatory tumors. In addition, we also found that the expressions of these targets were positively correlated with TMB.

Conclusion

Based on multidisciplinary analysis, we preliminarily identified potential targets of CEP for LUSC treatment and suggested that CEP may play a role in regulating LUSC stemness.

Identification of a group of bisbenzylisoquinoline (BBIQ) compounds as ferroptosis inhibitors

Ferroptosis induced by detrimental accumulation of lipid peroxides has been recently linked to a variety of pathological conditions ranging from acute tissue injuries to chronic degenerative diseases and suppression of ferroptosis by small chemical inhibitors is beneficial to the prevention and treatment of these diseases. However, in vivo applicable small chemical ferroptosis inhibitors are limited currently. In this study, we screened an alkaloid natural compound library for compounds that can inhibit RSL3-induced ferroptosis in HT1080 cells and identified a group of bisbenzylisoquinoline (BBIQ) compounds as novel ferroptosis-specific inhibitors. These BBIQ compounds are structurally different from known ferroptosis inhibitors and they do not appear to regulate iron homeostasis or lipid ROS generation pathways, while they are able to scavenge 1,1-diphenyl-2-picryl-hydrazyl (DPPH) in cell-free reactions and prevent accumulation of lipid peroxides in living cells. These BBIQ compounds demonstrate good in vivo activities as they effectively protect mice from folic acid-induced renal tubular ferroptosis and acute kidney injury. Several BBIQ compounds are approved drugs in Japan and China for traditional uses and cepharanthine is currently in clinical trials against SARS-CoV-2, our discovery of BBIQs as in vivo applicable ferroptosis inhibitors will expand their usage to prevent ferroptotic tissue damages under various pathological conditions.

Cepharanthine Attenuates Early Brain Injury after Subarachnoid Hemorrhage in Mice via Inhibiting 15-Lipoxygenase-1-Mediated Microglia and Endothelial Cell Ferroptosis

Background

Ferroptosis is a newly identified form of programmed cell death caused by iron-dependent lipid peroxidation. Our study was designed to determine the expression patterns and role of 15-lipoxygenase-1 (ALOX15) in subarachnoid hemorrhage (SAH) and to investigate whether cepharanthine (CEP) can inhibit ferroptosis by inhibiting ALOX15 in specific cell types.

Methods

A mouse model of SAH was developed by the endovascular perforation method. bEend.3 endothelial cells and BV2 microglial cells as well as RSL3 and hemin were used to simulate SAH in vitro. Mice and cell lines were treated with CEP and a group of specific oxygenase inhibitors to explore the protection effect from ferroptosis. Lipid peroxidation staining with BODIPY 581/591 C11 and transmission electron microscopy were used to identify ferroptosis in vitro and in vivo.

Results

In the present study, the accumulation of lipid peroxide, a defect in the glutathione peroxidase 4 (GPx4)/glutathione (GSH) antioxidant system, highly expressed ALOX15 in microglia and endothelium, and ferroptotic changes in microglial mitochondria confirmed the occurrence of ferroptosis after SAH in vivo. Further, CEP was shown to inhibit ferroptosis and improve neurological function by downregulating the expression of ALOX15. During in vitro experiments, we investigated the important role ALOX15 in RSL3-induced endothelial ferroptosis. In addition, we found that M2-type microglia are more sensitive to RSL3-induced ferroptosis than M1-type microglia and that hemin probably induced ferroptosis in M2-type microglia by increasing ALOX15 levels and decreasing GPx4 levels. The effect of CEP treatment was also demonstrated in vitro.

Conclusions

In summary, to the best of our knowledge, this is the first study demonstrating that ferroptosis occurred in the microglia and endothelium after SAH, and this process was facilitated by increased ALOX15 levels. More importantly, treatment with CEP could inhibit ferroptosis through downregulating the expression of ALOX15.

Cepharanthine: An update of its mode of action, pharmacological properties and medical applications

BACKGROUND

Cepharanthine (CEP) is a drug used in Japan since the 1950s to treat a number of acute and chronic diseases, including treatment of leukopenia, snake bites, xerostomia and alopecia. It is the only approved drug for Human use in the large class of bisbenzylisoquinoline alkaloids. This natural product, mainly isolated from the plant Stephania cephalantha Hayata, exhibits multiple pharmacological properties including anti-oxidative, anti-inflammatory, immuno-regulatory, anti-cancer, anti-viral and anti-parasitic properties.

PURPOSE

The mechanism of action of CEP is multifactorial. The drug exerts membrane effects (modulation of efflux pumps, membrane rigidification) as well as different intracellular and nuclear effects. CEP interferes with several metabolic axes, primarily with the AMP-activated protein kinase (AMPK) and NFκB signaling pathways. In particular, the anti-inflammatory effects of CEP rely on AMPK activation and NFκB inhibition.

CONCLUSION

In this review, the historical discovery and development of CEP are retraced, and the key mediators involved in its mode of action are presented. The past, present, and future of CEP are recapitulated. This review also suggests new opportunities to extend the clinical applications of this well-tolerated old Japanese drug.

Metabolomic analysis of date palm seedlings exposed to salinity and silicon treatments

Silicon is known to promote plant growth as well as stress tolerance of plants. The current study was undertaken to assess the growth promoting effect of silicon on date palm seedling development as well as its ability to abate some of the negative effects of salinity. In this study, date palm seedlings were treated with silicon and sodium chloride salts, and the effect of these salts on some physiological parameters of the plants was determined. In addition, a global nontargeted metabolomics analysis was performed for the leaf and root tissues using liquid chromatography-mass spectrometry (LC-MS). The results showed that under non-stress conditions, silicon treatment enhanced the growth of the date palm seedlings, however, under salinity, silicon slightly mitigates the negative effects of salt stress on the date palm seedlings although it enhances the potassium accumulation under this condition. The global metabolomics analysis has identified a total of 1,101 significant differentially accumulated (p, q ≤ 0.05) metabolites in leaves and roots under silicon, salinity or their combination. A differential pairwise metabolic profile comparison revealed the accumulation of distinct metabolites in response to silicon and salinity treatments such as antioxidant compounds pyridoxine, cepharanthine, allithiamine, myristic acid and boldine; osmoregulators such as mucic acid; along with the accumulation of detoxification intermediates such as S-D-lactoylglutathione, beta-cyano-L-alanine and gamma-glutamyl-conjugates. In addition, histochemical analyses revealed that application of silicon significantly (p ≤ 0.05) enhanced the formation of the Casparian strip. Identification of the differentially accumulated metabolites could offer an insight into how silicon is able to promote growth and salinity tolerance in date palms.

Pharmacological Effects and Mechanisms of Chinese Medicines Modulating NLRP3 Inflammasomes in Ischemic Cardio/Cerebral Vascular Disease

Cardio/cerebral-vascular diseases seriously threaten human health and are the leading cause of death. As such, there is great interest in identifying a potential mechanism that controls the development process of cardio/cerebral vascular diseases. Present studies demonstrate that inflammasomes play an important role in the process of ischemic cardio/cerebral vascular diseases (ICCVDs). Among the pathological process of ICCVDs, inflammasomes activated the sterile inflammatory response that accelerated the development of diseases and aggravated the acute lesion of tissue. As the most thoroughly studied inflammasome, the NLRP3 inflammasome has been proven to be a potential therapeutic target for ICCVDs. In this review, we summarized the mechanisms of Chinese herbal medicine which can affect ICCVDs via the regulation of the NLRP3 inflammasome. Our study discovers that active compounds of Chinese medicines have a negative effect on NLRP3 in different ICCVDs models. Astragaloside IV may influence the receptor of the cell membrane to inhibit NLRP3 activation. Resveratrol, colchicinesis, salvianolic acid B, chrysophanol and sulforaphane may directly damage the formation of NLRP3 by inhibiting ASC or Caspase-1. Most of the active natural compounds can negatively regulate the downstream products of NLRP3 inflammasome such as IL-18 and IL1 β . In addition, Chinese medicines such as sinomenine, ruscogenin, resveratrol, arctigenin and cepharanthineas may downregulate NLRP3 inflammasome by inducing autophagy activation. Due to the advantages of multi-target effects, Chinese herbal medicine can be treated as a splendid therapy for ICCVDs by inhibiting NLRP3 inflammasome.

New Potential Pharmacological Functions of Chinese Herbal Medicines via Regulation of Autophagy

Autophagy is a universal catabolic cellular process for quality control of cytoplasm and maintenance of cellular homeostasis upon nutrient deprivation and environmental stimulus. It involves the lysosomal degradation of cellular components such as misfolded proteins or damaged organelles. Defects in autophagy are implicated in the pathogenesis of diseases including cancers, myopathy, neurodegenerations, infections and cardiovascular diseases. In the recent decade, traditional drugs with new clinical applications are not only commonly found in Western medicines, but also highlighted in Chinese herbal medicines (CHM). For instance, pharmacological studies have revealed that active components or fractions from Chaihu (Radix bupleuri), Hu Zhang (Rhizoma polygoni cuspidati), Donglingcao (Rabdosia rubesens), Hou po (Cortex magnoliae officinalis) and Chuan xiong (Rhizoma chuanxiong) modulate cancers, neurodegeneration and cardiovascular disease via autophagy. These findings shed light on the potential new applications and formulation of CHM decoctions via regulation of autophagy. This article reviews the roles of autophagy in the pharmacological actions of CHM and discusses their new potential clinical applications in various human diseases.

Cepharanthine alleviates liver injury in a rodent model of limb ischemia-reperfusion

OBJECTIVES

Limb ischemia-reperfusion (I/R) causes remote organ injury (e.g., liver injury). Oxidation and inflammation are crucial mechanisms. We investigated the effects of cepharanthine, a potent antioxidative and anti-inflammatory drug, on alleviating liver injury induced by limb I/R.

METHODS

Twenty-four adult male Sprague-Dawley rats were randomized to receive sham operation (Sham), Sham plus cepharanthine, I/R, or I/R plus cepharanthine and designated as the Sham, Sham+Cep, I/R, or I/R+Cep group, respectively (n = 6 in each group). I/R was induced by applying rubber band tourniquets high around each hind limb for 3 hours followed by reperfusion for 24 hours.

RESULTS

The plasma levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) of the Sham and Sham+Cep groups were low, and the levels of AST and ALT of the I/R group were significantly higher than those of the Sham group (both p<0.001). By contrast, the AST and ALT of the I/R+Cep group were significantly lower than those of the I/R group (both p<0.001). The hepatic levels of nitric oxide (NO), malondialdehyde (MDA), macrophage inflammatory protein 2 (MIP-2), interleukin-6 (IL-6), and cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) of the Sham and Sham+Cep groups were also low. As expected, the NO, MDA, MIP-2, IL-6, and COX-2/PGE2 of the I/R group were significantly higher than those of the Sham group (all p<0.001). By contrast, the NO, MDA, MIP-2, IL-6, and COX-2/PGE2 of the I/R+Cep group were significantly lower than those of the I/R group (all p<0.05).

CONCLUSION

Cepharanthine alleviates liver injury in a rodent model of limb I/R. The mechanisms may involve reducing oxidation and inflammation.

Ethnobotany, phytochemistry and pharmacology of Stephania rotunda Lour

ETHNOPHARMACOLOGICAL RELEVANCE

Stephania rotunda Lour. (Menispermaceae) is an important traditional medicinal plant that is grown in Southeast Asia. The stems, leaves, and tubers have been used in the Cambodian, Lao, Indian and Vietnamese folk medicine systems for years to treat a wide range of ailments, including asthma, headache, fever, and diarrhoea.

AIM OF THE REVIEW

To provide an up-to-date, comprehensive overview and analysis of the ethnobotany, phytochemistry, and pharmacology of Stephania rotunda for its potential benefits in human health, as well as to assess the scientific evidence of traditional use and provide a basis for future research directions.

MATERIAL AND METHODS

Peer-reviewed articles on Stephania rotunda were acquired via an electronic search of the major scientific databases (Pubmed, Google Scholar, and ScienceDirect). Data were collected from scientific journals, theses, and books.

RESULTS

The traditional uses of Stephania rotunda were recorded in countries throughout Southeast Asia (Cambodia, Vietnam, Laos, and India). Different parts of Stephania rotunda were used in traditional medicine to treat about twenty health disorders. Phytochemical analyses identified forty alkaloids. The roots primarily contain l-tetrahydropalmatine (l-THP), whereas the tubers contain cepharanthine and xylopinine. Furthermore, the chemical composition differs from one region to another and according to the harvest period. The alkaloids exhibited approximately ten different pharmacological activities. The main pharmacological activities of Stephania rotunda alkaloids are antiplasmodial, anticancer, and immunomodulatory effects. Sinomenine, cepharanthine, and l-stepholidine are the most promising components and have been tested in humans. The pharmacokinetic parameters have been studied for seven compounds, including the three most promising compounds. The toxicity has been evaluated for liriodenine, roemerine, cycleanine, l-tetrahydropalmatine, and oxostephanine.

CONCLUSION

Stephania rotunda is traditionally used for the treatment of a wide range of ailments. Pharmacological investigations have validated different uses of Stephania rotunda in folk medicine. The present review highlights the three most promising compounds of Stephania rotunda, which could constitute potential leads in various medicinal fields, including malaria and cancer.

Radical scavenging of white tea and its flavonoid constituents by electron paramagnetic resonance (EPR) spectroscopy

White tea (WT) presents high levels of catechins, which are known to reduce oxidative stress. WT is the least processed tea, unfermented and prepared only from very young tea leaves. The subject of this paper is the use of the spin trap method and electron paramagnetic resonance (EPR) spectroscopy as the analytical tool to measure, for the first time, the radical scavenging activity of WT and its major catechin components, epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC), and epigallocatechin-3-gallate (EGCG), against the methoxy radical, using ferulic acid as antioxidant pattern. The antioxidant activity has been measured by the decrease of the intensity of the spectral bands of the adduct DMPO-OCH3 in the EPR with the amount of antioxidant in the reactive mixture. Tea leaves and buds were extracted with waterless methanol. It has been proved that tea compounds with more antiradical activity against methoxy radical are those with the gallate group, EGCG and ECG.

Therapeutic potential of the biscoclaurine alkaloid, cepharanthine, for a range of clinical conditions

Cepharanthine (CEP) is a naturally occurring alkaloid extracted from the plant Stephania cepharantha Hayata. It has been widely used in Japan for more than 40 years to treat a wide variety of acute and chronic diseases. CEP inhibits tumor necrosis factor (TNF)-α-mediated NFκB stimulation, plasma membrane lipid peroxidation and platelet aggregation and suppresses cytokine production. It has also been shown to scavenge free radicals and to have a protective effect against some of the responses mediated by pro-inflammatory cytokines such as TNF-α, interleukin (IL)-1β and IL6. CEP has successfully been used to treat a diverse range of medical conditions, including radiation-induced leukopenia, idiopathic thrombocytopenic purpura, alopecia areata, alopecia pityrodes, venomous snakebites, xerostomia, sarcoidosis, refractory anemia and various cancer-related conditions. No safety issues have been observed with CEP, and side effects are very rarely reported.

Remarkable enhancement of cytotoxicity of onconase and cepharanthine when used in combination on various tumor cell lines

Onconase (Onc), a ribonuclease from oocytes or early embryos of Northern Leopard frog (Rana pipiens), is cytostatic and cytotoxic to a variety of tumor lines in vitro, inhibits growth of tumors in animal in vivo models and is currently in Phase IIIb clinical trials for malignant mesothelioma where it displays antitumor activity with minor overall toxicity to the patient. One of the characteristic features of Onc is a synergism with a variety of other antitumor modalities. Cepharanthine (Cep), a biscoclaurine alkaloid from Stephania cepharantha Hayata, is widely used in Japan to treat variety of ailments. It also shows low toxicity to patients. The aim of the present study was to assess the interaction of these two drugs on different tumor cell lines. When human promyelocytic leukemia HL-60, histiomonocytic lymphoma U937, multiple myeloma RPMI-8228, prostate carcinoma DU 145 and prostate adenocarcinoma LNCaP cells were exposed to relatively low concentrations of Onc or Cep their growth rates were somewhat suppressed but the cells were still able to proliferate. Cell growth, however, was totally abolished in each of these cell lines when treated with Onc and Cep combined. The frequency of apoptosis was also many-fold higher in cultures treated with a combination of Onc and Cep than in respective cultures treated with Onc or Cep alone. The mechanism of the observed synergism is unclear but it may be associated with the Onc activity in targeting microRNAs and/or NFkappaB and Cep activity also targeting NFkappaB. The data suggest that the combination of these two drugs, that individually express a low toxic profile, may have strong antitumor potential.

The effects of biscoclaurine alkaloid cepharanthine on mammalian cells: implications for cancer, shock, and inflammatory diseases

The extract of Stephania cepharantha Hayata contains biscoclaurine alkaloids such as cepharanthine, which have been used widely in Japan for the treatment of patients with radiation-induced leukopenia, alopecia areata, exudative otitis media, and venomous snakebites. Many investigations have proven that the alkaloid cepharanthine exerts diverse pharmacological effects that include membrane-stabilizing, multidrug resistance-reversing, antitumor, apoptosis-inducing, anti-inflammatory, free radical scavenging, anti-HIV-1, antiallergic and immunomodulatory effects. The purpose of our review is to describe various therapeutic approaches using cepharanthine and their potential efficacy.