Madagascine Induces Vasodilatation via Activation of AMPK

Role of emodin in atherosclerosis and other cardiovascular diseases: Pharmacological effects, mechanisms, and potential therapeutic target as a phytochemical

The morbidity and mortality of cardiovascular diseases (CVDs) are increasing in recent years, and atherosclerosis (AS), a major CVD, becomes a disorder that afflicts human beings severely, especially the elders. AS is recognized as the primary cause and pathological basis of some other CVDs. The active constituents of Chinese herbal medicines have garnered increasing interest in recent researches owing to their influence on AS and other CVDs. Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a naturally occurring anthraquinone derivative found in some Chinese herbal medicines such as Rhei radix et rhizome, Polygoni cuspidati rhizoma et radix and Polygoni multiflori root. In this paper, we first review the latest researches about emodin's pharmacology, metabolism and toxicity. Meanwhile, it has been shown to be effective in treating CVDs caused by AS in dozens of previous studies. Therefore, we systematically reviewed the mechanisms by which emodin treats AS. In summary, these mechanisms include anti-inflammatory activity, lipid metabolism regulation, anti-oxidative stress, anti-apoptosis and vascular protection. The mechanisms of emodin in other CVDs are also discussed, such as vasodilation, inhibition of myocardial fibrosis, inhibition of cardiac valve calcification and antiviral properties. We have further summarized the potential clinical applications of emodin. Through this review, we hope to provide guidance for clinical and preclinical drug development.

A world tour in the name of natural products

BACKGROUND

Names of natural products (NP) are usually given depending on the species of origin, be it a plant, a marine organism or a microbial species. In some cases, names have been given with reference to people, animals, music, foods or places. Many NP refer to countries, cities or specific places such as mountains, deserts, seas and oceans.

PURPOSE

On the basis of NP names, a world tour has been imagined referring to more than one hundred NP with names evocative of over 50 countries and regions.

RESULTS

The world tour goes from UK (britannin) to Italy (vaticanol) in Europe, from Uganda (ugandoside) to Senegal (senegalene, senegalenines) in Africa, from Brazil (brasilin) to Chile (santiaguine) in South America, from Utah (utahin) to Florida (floridanolide) in the US. It includes Central America (mexicanin, panamine) and the Caribbean islands (jamaicin, bahamaolides). It also crosses Alaska (alaskene) and Canada (quebecol, canadaline). The tour continues throughout Asia, from Thailand (thailandine) to China (Chinaldine) and Pakistan (pakistanamine), to finally reaches Oceania with Australia (australigenin) and Vanuatu (vanuatine), among other countries. This virtual journey, without bordure or wall, brings us to the highest mountains (himalayamine), the deepest oceans (pacificins) and the largest deserts (desertomycin).

CONCLUSION

In the current period of COVID-19 pandemia, with restricted opportunities for international travels, this NP name-based virtual journey offers a world tour to learn more from nature and to inspire scientists to contribute to the field of NP discovery and drug design. There are also limitations associated with the use of trivial names for NP. NP names can be further exploited for teaching and learning.

The pharmacology, toxicology and therapeutic potential of anthraquinone derivative emodin

Emodin (1, 3, 8-trihydroxy-6-methylanthraquinone) is a derived anthraquinone compound extracted from roots and barks of pharmaceutical plants, including Rheum palmatum, Aloe vera, Giant knotweed, Polygonum multiflorum and Polygonum cuspidatum. The review aims to provide a scientific summary of emodin in pharmacological activities and toxicity in order to identify the therapeutic potential for its use in human specific organs as a new medicine. Based on the fundamental properties, such as anticancer, anti-inflammatory, antioxidant, antibacterial, antivirs, anti-diabetes, immunosuppressive and osteogenesis promotion, emodin is expected to become an effective preventive and therapeutic drug of cancer, myocardial infarction, atherosclerosis, diabetes, acute pancreatitis, asthma, periodontitis, fatty livers and neurodegenerative diseases. This article intends to provide a novel insight for further development of emodin, hoping to reveal the potential of emodin and necessity of further studies in this field.

Molecular Mechanisms of Action of Emodin: As an Anti-Cardiovascular Disease Drug

Emodin is a natural occurring anthraquinone derivative isolated from roots and barks of numerous plants, molds, and lichens. It is found to be an active ingredient in different Chinese herbs including Rheum palmatum and Polygonam multiflorum, and it is a pleiotropic molecule with diuretic, vasorelaxant, anti-bacterial, anti-viral, anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. Moreover, emodin has also been shown to have a wide activity of anti-cardiovascular diseases. It is mainly involved in multiple molecular targets such as inflammatory, anti-apoptosis, anti-hypertrophy, anti-fibrosis, anti-oxidative damage, abnormal, and excessive proliferation of smooth muscle cells in cardiovascular diseases. As a new type of cardiovascular disease treatment drug, emodin has broad application prospects. However, a large amount of evidences detailing the effect of emodin on many signaling pathways and cellular functions in cardiovascular disease, the overall understanding of its mechanisms of action remains elusive. In addition, by describing the evidence of the effects of emodin in detail, the toxicity and poor oral bioavailability of mice have been continuously discovered. This review aims to describe a timely overview of emodin related to the treatment of cardiovascular disease. The emphasis is to summarize the pharmacological effects of emodin as an anti-cardiovascular drug, as well as the targets and its potential mechanisms. Furthermore, the treatment of emodin compared with conventional cardiovascular drugs or target inhibitors, the toxicity, pharmacokinetics and derivatives of emodin were discussed.

Role of Sphingosylphosphorylcholine in Tumor and Tumor Microenvironment

Sphingosylphosphorylcholine (SPC) is a unique type of lysosphingolipid found in some diseases, and has been studied in cardiovascular, neurological, and inflammatory phenomena. In particular, SPC’s studies on cancer have been conducted mainly in terms of effects on cancer cells, and relatively little consideration has been given to aspects of tumor microenvironment. This review summarizes the effects of SPC on cancer and tumor microenvironment, and presents the results and prospects of modulators that regulate the various actions of SPC.

Recent acquisitions on oxyprenylated secondary metabolites as anti-inflammatory agents

Oxyprenylated secondary metabolites from plants, fungi, and bacteria, and their semisynthetic derivatives have been subject of growing interest during the last decade. Such natural products in fact have been discovered as potentially novel lead compounds for a series of pharmacological activities, mainly in terms of anti-cancer and anti-inflammatory ones. Especially during the last 5 years, a wider panel of prenyloxy secondary metabolites have been investigated from chemical and biological points of view and these include benzoic acids, alcohols, aldehydes, chalcones, anthraquinones, 1,4-naphthoquinones, other than the well known oxyprenylated ferulic acid and coumarin derivatives. The aim of this comprehensive review is to focus on the anti-inflammatory properties and related mechanisms of action of selected classes of oxyprenylated naturally occurring compounds and their semisynthetic analogues covering the literature period from 2011 to 2017. In vitro and in vivo data on their pharmacological activity triggering different pathways of the overall inflammatory machinery as well as structure activity relationship acquisitions will be summarized in order to make a detailed survey of the most recent reports on the potential of the title compounds as a novel class of anti-inflammatory agents.