Effect of aqueous extract of Astragalus membranaceus on behavioral cognition of rats living at high altitude.

OBJECTIVE: To investigate the effect of aqueous extract of Astragalus membranaceus on cognitive ability of rats living at high altitude. METHODS: Rats were exposed to a simulated highaltitude hypobaric hypoxia chamber. The behavior of rats was tested by eight-arm maze. The contents of malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS) and activity of total superoxide dismutase (T-SOD) in hippocampus were measured. The expressions of mammalian target of rapamycin (mTOR) and cleaved capase-3 in hippocampus were determined by reverse transcription-polymerase chain reaction and Western blot. RESULTS: The behavioral cognitive ability of the hypoxic control group was significantly lower than that of the normoxic control group. Under hypoxic environment, after the administration of aqueous extract of Astragalus membranaceus, the behavioral cognitive ability of rats was significantly improved. In hippocampal tissue, the content of MDA and ROS were significantly decreased, while the content of GSH and activity of T-SOD in hippocampus were significantly increased. The mRNA expression of mTOR and P70S6K and the protein expression of p-mTOR were significantly increased; the mRNA expression of 4E-binding protein 1 (4E-BP1) and the protein expression of phosphorylated-4E-BP1 (p-4EBP1) and cleaved capase-3 were significantly decreased. CONCLUSION: When the rats are exposed to high altitude hypoxia, the behavioral cognitive ability could be significantly reduced. Aqueous extract of Astragalus membranaceus can significantly improve cognitive function in rats under hypoxia. The potential mechanism is related to improving oxidative stress, reducing the accumulation of free radicals and metabolites, and activating mTOR signaling pathway.

A review on the structure and pharmacological activity of phenylethanoid glycosides.

Phenylethanoid glycosides (PhGs) are compounds made of phenylethyl alcohol, caffeic acid and glycosyl moieties. The first published references about phenylethanoid glycosides concerned the isolation of echinacoside from Echinaceu ungustifolia (Asteraceae) in 1950 and verbascoside from Verbascum sinuatum (Scrophulariaceae) in 1963. Over the past 60 years, many compounds with these structural characteristics have been isolated from natural sources, and most of these compounds possess significant bioactivities, including antibacterial, antitumor, antiviral, anti-inflammatory, neuro-protective, antioxidant, hepatoprotective, and immunomodulatory activities, among others. In this review, we will summarize the phenylethanoid glycosides described in recent papers and list all the compounds that have been isolated over the past few decades. We will also attempt to present and assess recent studies about the separation, extraction, determination, and pharmacological activity of the excellent natural components, phenylethanoid glycosides.

Gardenia jasminoides Ellis: Ethnopharmacology, phytochemistry, and pharmacological and industrial applications of an important traditional Chinese medicine.

ETHNOPHARMACOLOGICAL RELEVANCE: Gardenia jasminoides Ellis is a popular shrub in the Rubiaceae family. The desiccative ripe fruits of this plant (called Zhizi in China) are well known and frequently used not only as an excellent natural colourant, but also as an important traditional medicine for the treatment of different diseases, such as reducing fire except vexed, clearing away heat evil, and cooling blood and eliminating stasis to activate blood circulation. It has also been declared as the first batch of dual-purpose plants used for food and medical functions in China. AIM OF THE STUDY: This review aims to provide a critical and systematic summary of the traditional uses, ethnopharmacology, phytochemistry, pharmacology, toxicity and industrial applications of Gardenia jasminoides Ellis and briefly proposes several suggestions for future application prospects. MATERIALS AND METHODS: The related information on Gardenia jasminoides Ellis was obtained from internationally recognized scientific databases through the Internet (PubMed, CNKI, Google Scholar, Baidu Scholar, Web of Science, Medline Plus, ACS, Elsevier and Flora of China) and libraries. RESULTS: Approximately 162 chemical compounds have been isolated and identified from this herb. Among them, iridoid glycosides and yellow pigment are generally considered the main bioactive and characteristic ingredients. Various pharmacological properties, such as a beneficial effect on the nervous, cardiovascular and digestive systems, hepatoprotective activity, antidepressant activity, and anti-inflammatory activity, were also validated in vitro and in vivo. Moreover, geniposide and genipin are the most important iridoid compounds isolated from Gardenia jasminoides Ellis, and genipin is the aglycone of geniposide. As the predominant active ingredient with a distinct pharmacological activity, genipin is also an outstanding biological crosslinking agent. Gardenia yellow pigment has also been widely used as an excellent natural dye-stuff. Hence, Gardenia jasminoides Ellis has been applied to many other fields, including the food industry, textile industry and chemical industry, in addition to its predominant medicinal uses. CONCLUSIONS: According to this review, Gardenia jasminoides Ellis is outstanding traditional medical plant used in medicine and food. Pharmacological investigations support the traditional use of this herb and may validate the folk medicinal use of Gardenia jasminoides Ellis to treat different diseases. Iridoid glycosides are potential medicines. Gardenia yellow pigment has been the most important source of a natural colourant for food, cloth and paint for thousands of years. This herb has made great contributions to human survival and development. Moreover, it has also achieved outstanding progress in human life and even in art. Although Gardenia jasminoides Ellis has extremely high and comprehensive utilization values, it is still far from being completely explored. Therefore, the comprehensive development of Gardenia jasminoides Ellis deserves further analysis.

Antioxidant activity and potential ameliorating effective ingredients for high altitude-induced fatigue from Gansu Maxianhao (Pedicularis Kansuensis Maxim.).

OBJECTIVE: To investigate the antioxidant property and potential ameliorating effective ingredients for high altitude-induced fatigue from Gansu Maxianhao (Pedicularis Kansuensis Maxim.). METHODS: Macroporous adsorptive resin combined with polyamide chromatographic column was used to obtain water extract (P1), high polar part (P2), iridoid glycosides part (P3) and phenylethanoid glycosides part (P4) of Gansu Maxianhao (Pedicularis Kansuensis Maxim.). Antioxidant activity of each part was investigated employing a series of in vitro models. Hematoxylin-eosin staining, analysis of blood biochemical parameters, along with molecular analyses examining oxidative stress makers, metabolite, metabolic enzyme and energy substance in liver, skeletal muscle and/or serum were further measured. RESULTS: The results showed phenylethanoid glycosides (PhGs) exhibited more effective with 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability, 2-2-Azinbis (3-ehtylbenzothiazolin-6-sulfnicAcid) Diammonium Salt+ scavenging activity, hydroxyl radical scavenging activity, reducing ability and antioxidant activity to varying extents. Under a hypobaric hypoxia attack in a hypobaric chamber (8000 m, 7 consecutive days), PhGs was administered to BALB/C mice at doses of 50, 200, 400 mg/kg and antifatigue property was evaluated using a swimming test at an altitude of 4000 m. The results showed that PhGs of Gansu Maxianhao (Pedicularis Kansuensis Maxim.) could significantly prolong the burden swimming time of mice, reduce the hypoxia-induced oxidative stress, remove the accumulated products of metabolism, improve the energy metabolism as well as improve preservation of endogenous glycogen stores. CONCLUSION: The ameliorating effect against altitude-induced fatigue of PhGs from Gansu Maxianhao (Pedicularis Kansuensis Maxim.) might come from the alleviation of oxidative stress, reduction of the adverse metabolic products, normalizing energy metabolism and increasing energy substances reserves. PhGs is a potential antioxidant and novel remedy for fatigue due to high-altitude hypoxia.

Effect and mechanism of verbascoside on hypoxic memory injury in plateau.

Verbascoside is a water-soluble natural phenylethanoid glycoside and distributes widely in plants. It has been proved with antioxidant, neuroprotective, anti-inflammatory, antibacterial, and immunomodulatory bioactivities. In this experiment, the effect and mechanism of verbascoside on hypoxic memory injury were studied in a low-pressure and low-oxygen chamber. Verbascoside (50, 150, and 300 mg/kg) was intragastrically administered once a day for 7 days. On the fourth day, rats were placed in the chamber to simulate a 7,500 m high-altitude environment The eight-arm maze was used to test the memory ability. The levels of MDA, GSH, and T-SOD in plasma, brain-NH, and hippocampus were detected. The mRNA expression of mTOR, P70S6K, and 4E-BP1 in the hippocampus tissue was determined by PCR. The protein expression of P-mTOR, P-P70S6K, P-4E-BP1, and Cleaved Caspase-3 in the hippocampus tissue was determined by western blot. The results indicated that administration with verbascoside could obviously reduce the working memory error, reference memory error, total errors, and total time; relieve the neuron damage in CA1 region of the hippocampus; and decrease the oxidative stress correlation enzyme activity in plasma, brain, and hippocampus. The amelioration of verbascoside on high altitude-induced memory impairment may be associated with the adjustment of oxidative stress and mTOR signaling pathway.