Phloridzin-sensitive transport of echinacoside and acteoside and altered intestinal absorption route after application of Cistanche tubulosa extract

Research Progress and Trends of Phenylethanoid Glycoside Delivery Systems

Background: Phenylethanoid glycosides (PhGs) are obtained from a wide range of sources and show strong biological and pharmacological activities, such as antioxidant, antibacterial and neuroprotective effects. However, intestinal malabsorption and the low bioavailability of PhGs seriously affect their application. Delivery systems are an effective method to improve the bioavailability of active substances. Scope and approach: In this article, the biological activities of and delivery systems for PhGs are introduced. The application statuses of delivery systems for echinacoside, acteoside and salidroside are reviewed. Finally, the problems of the lack of uniform standards for delivery systems and the poor targeted delivery accuracy of PhGs in the current research are proposed and suggestions for future research are put forward based on those problems. Key findings and conclusions: Although there are still some problems in the delivery system of phenylethanoside, such as inconsistent standards and inaccurate delivery, phenylethanoside itself has been proven to have a variety of physiological activities. Therefore, the action mechanism and application of phenylethanoside and its delivery system should be studied further.

Herba Cistanche (Rou Cong Rong): A Review of Its Phytochemistry and Pharmacology

Herba Cistanche, known as Rou Cong Rong in Chinese, is a very valuable Chinese herbal medicine that has been recorded in the Chinese Pharmacopoeia. Rou Cong Rong has been extensively used in clinical practice in traditional herbal formulations and has also been widely used as a health food supplement for a long time in Asian countries such as China and Japan. There are many bioactive compounds in Rou Cong Rong, the most important of which are phenylethanoid glycosides. This article summarizes the up-to-date information regarding the phytochemistry, pharmacology, processing, toxicity and safety of Rou Cong Rong to reveal its pharmacodynamic basis and potential therapeutic effects, which could be of great value for its use in future research.

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.

Cistanches Herba: An overview of its chemistry, pharmacology, and pharmacokinetics property

ETHNOPHARMACOLOGICAL RELEVANCE

Cistanches Herba is an Orobanchaceae parasitic plant. As a commonly used Traditional Chinese Medicine (TCM), its traditional functions include treating kidney deficiency, impotence, female infertility and senile constipation. Chemical analysis of Cistanches Herba revealed that phenylethanoid glycosides, iridoids, lignans, oligosaccharides, and polysaccharides were the main constituents. Pharmacological studies demonstrated that Cistanches Herba exhibited neuroprotective, immunomodulatory, hormonal balancing, anti-fatigue, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, anti-viral, and anti-tumor effects, etc. The aim of this review is to provide updated, comprehensive and categorized information on the phytochemistry, pharmacological research and pharmacokinetics studies of the major constituents of Cistanches Herba.

MATERIALS AND METHODS

The literature search was conducted by systematic searching multiple electronic databases including SciFinder, ISI Web of Science, PubMed, Google Scholar and CNKI. Information was also collected from journals, local magazines, books, monographs.

RESULTS

To date, more than 100 compounds have been isolated from this genus, include phenylethanoid glycosides, carbohydrates, lignans, iridoids, etc. The crude extracts and isolated compounds have exhibited a wide range of in vitro and in vivo pharmacologic effects, such as neuroprotective, immunomodulatory, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, and anti-tumor effects. The phenylethanoid glycosides, echinacoside and acteoside have attracted the most attention for their significantly neuropharmacology effects. Pharmacokinetic studies of echinacoside and acteoside also have also been summarized.

CONCLUSION

Phenylethanoid glycosides have demonstrated wide pharmacological actions and have great clinical value if challenges such as poor bioavailability, fast and extensive metabolism are addressed. Apart from phenylethanoid glycosides, other constituents of Cistanches Herba, their pharmacological activities and underlying mechanisms are also need to be studied further.

Echinacoside's nigrostriatal dopaminergic protection against 6-OHDA-Induced endoplasmic reticulum stress through reducing the accumulation of Seipin

Parkinson's disease (PD) is one of the most common neurodegenerative diseases. Recent epidemiological studies suggest that echinacoside (ECH), a phenylethanoid glycoside found in Cistanche deserticola, has a protective effect against the development of PD. However, the detailed mechanisms of how ECH suppresses neuronal death have not been fully elucidated. In this study, we confirmed that ECH protects nigrostriatal neurons against 6‐hydroxydopamine (6‐OHDA)‐induced endoplasmic reticulum stress (ERS) in vivo and in vitro. ECH rescued cell viability in damaged cells and decreased 6‐OHDA‐induced reactive oxygen species accumulation in vitro. It also rescued tyrosine hydroxylase and dopamine transporter expression in the striatum, and decreased α‐synuclein aggregation following 6‐OHDA treatment in vivo. The validated mechanism of ECH activity was the reduction in the 6‐OHDA‐induced accumulation of seipin (Berardinelli–Seip congenital lipodystrophy 2). Seipin has been shown to be a key molecule related to motor neuron disease and was tightly associated with ERS in a series of in vivo studies. ECH attenuated seipinopathy by promoting seipin degradation via ubiquitination. ERS was relieved by ECH through the Grp94/Bip‐ATF4‐CHOP signal pathway.