Study of the effects of total flavonoids of Astragalus on atherosclerosis formation and potential mechanisms

Baoyuan decoction inhibits atherosclerosis progression through suppression peroxidized fatty acid and Src/MKK4/JNK pathway-mediated CD 36 expression

BACKGROUND

Baoyuan decoction (BYD) has been widely utilized as a traditional prescription for the treatment of various conditions such as coronary heart disease, aplastic anemia, and chronic renal failure. However, its potential efficacy in improving atherosclerosis has not yet been investigated.

PURPOSE

Our research aimed to assess the potential of BYD as an inhibitor of atherosclerosis and uncover the underlying mechanism by which it acts on foam cell formation.

STUDY DESIGN AND METHODS

High-fat diet-induced ApoE-/- mice were employed to explore the effect of BYD on atherosclerosis. The differential metabolites in feces were identified and analyzed by LC-Qtrap-MS. In addition, we utilized pharmacological inhibition of BYD on foam cell formation induced by oxLDL in THP-1 cells to elucidate the underlying mechanisms specifically in macrophages.

RESULTS

The atherosclerotic plaque burden in the aortic sinus of ApoE-/- mice was notably reduced with BYD treatment, despite no significant alterations in plasma lipids. Metabolomic analysis revealed that BYD suppressed the increased levels of peroxidized fatty acids, specifically 9/13-hydroxyoctadecadienoic acid (9/13-HODE), in the feces of mice. As a prominent peroxidized fatty acid found in oxLDL, we confirmed that 9/13-HODE induced the overexpression of CD36 in THP-1 macrophages by upregulating PPARγ. In subsequent experiments, the decreased levels of CD36 triggered by oxLDL were observed after BYD treatment. This decrease occurred through the regulation of the Src/MMK4/JNK pathway, resulting in the suppression of lipid deposition in THP-1 macrophages.

CONCLUSIONS

These results illustrate that BYD exhibits potential anti-atherosclerotic effects by inhibiting CD36 expression to prevent foam cell formation.

Biosynthesis and Pharmacological Activities of Flavonoids, Triterpene Saponins and Polysaccharides Derived from Astragalus membranaceus

Astragalus membranaceus (A. membranaceus), a well-known traditional herbal medicine, has been widely used in ailments for more than 2000 years. The main bioactive compounds including flavonoids, triterpene saponins and polysaccharides obtained from A. membranaceus have shown a wide range of biological activities and pharmacological effects. These bioactive compounds have a significant role in protecting the liver, immunomodulation, anticancer, antidiabetic, antiviral, antiinflammatory, antioxidant and anti-cardiovascular activities. The flavonoids are initially synthesized through the phenylpropanoid pathway, followed by catalysis with corresponding enzymes, while the triterpenoid saponins, especially astragalosides, are synthesized through the universal upstream pathways of mevalonate (MVA) and methylerythritol phosphate (MEP), and the downstream pathway of triterpenoid skeleton formation and modification. Moreover, the Astragalus polysaccharide (APS) possesses multiple pharmacological activities. In this review, we comprehensively discussed the biosynthesis pathway of flavonoids and triterpenoid saponins, and the structural features of polysaccharides in A. membranaceus. We further systematically summarized the pharmacological effects of bioactive ingredients in A. membranaceus, which laid the foundation for the development of clinical candidate agents. Finally, we proposed potential strategies of heterologous biosynthesis to improve the industrialized production and sustainable supply of natural products with pharmacological activities from A. membranaceus, thereby providing an important guide for their future development trend.

In vitro effects of alcesefoliside and mauritianin, isolated from Astragalus monspessulanus subsp. monspessulanus, on the contractility of a. basilaris

Flavonoids are one of the most popular antioxidants in plants. Their varied pharmacological activities are important for these compounds in order to add and to complement conventional therapy. Alcesefoliside and mauritianin are rare flavonol triglycosides, isolated from the overground part of A. monspessulanus subsp. monspessulanus. The aim of the study was to examine the in vitro effects of the isolated flavonoids on the contractility of a. basilaris. Administered alone, at concentration 10 µM, alcesefoliside and mauritianin did not influence the vascular tone of segment of a. basilaris. The combination of both compounds, at 10 µM, revealed an increased response of the vascular tone of a. basilaris. These effects of the flavonoids suggest their possible beneficial effect as further candidates in the complex therapy of neurodegenerative disease.

7,8-Dihydroxyflavone and Neuropsychiatric Disorders: A Translational Perspective from the Mechanism to Drug Development

7,8-Dihydroxyflavone (7,8-DHF) is a kind of natural flavonoid with the potential to cross the blood-brain barrier. 7,8-DHF effectively mimics the effect of brain-derived neurotrophic factor (BDNF) in the brain to selectively activate tyrosine kinase receptor B (TrkB) and downstream signaling pathways, thus playing a neuroprotective role. The preclinical effects of 7,8-DHF have been widely investigated in neuropsychiatric disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), depression, and memory impairment. Besides the effect on TrkB, 7,8-DHF could also function through fighting against oxidative stress, cooperating with estrogen receptors, or regulating intestinal flora. This review focuses on the recent experimental studies on depression, neurodegenerative diseases, and learning and memory functions. Additionally, the structural modification and preparation of 7,8-DHF were also concluded and proposed, hoping to provide a reference for the follow-up research and clinical drug development of 7,8-DHF in the field of neuropsychiatric disorders.

Inhibition of Oxidative Stress: An Important Molecular Mechanism of Chinese Herbal Medicine (Astragalus membranaceus, Carthamus tinctorius L., Radix Salvia Miltiorrhizae, etc.) in the Treatment of Ischemic Stroke by Regulating the Antioxidant System

Ischemic stroke is a severe cerebrovascular disease with high mortality and morbidity. Traditional Chinese medicine (TCM) has been utilized for thousands of years in China and is becoming increasingly popular all over the world, especially for the treatments of ischemic stroke. More and more evidences have implicated that oxidative stress has been closely related with ischemic stroke. This review will concentrate on the evidence of the action mechanism of Chinese herbal medicine and its active ingredient in preventing ischemic stroke by modulating redox signaling and oxidative stress pathways and providing references for clinical treatment and scientific research applications.

Biological active ingredients of Astragali Radix and its mechanisms in treating cardiovascular and cerebrovascular diseases

BACKGROUND

With the rising age of the global population, the incidence rate of cardiovascular and cerebrovascular diseases (CCVDs) is increasing, which causes serious public health burden. The efforts for new therapeutic approaches are still being sought since the treatment effects of existing therapies are not quite satisfactory. Chinese traditional medicine proved to be very efficient in the treatment of CCVDs. Well described and established in Chinese medicine, Astragali Radix, has been commonly administered in the prophylaxis and cure of CCVDs for thousands of years.

PURPOSE

This review summarized the action mode and mechanisms of Astragali Radix phytochemicals on CCVDs, hoping to provide valuable information for the future application, development and improvement of Astragali Radix as well as CCVDs treatment.

METHODS

A plenty of literature on biological active ingredients of Astragali Radix used for CCVDs treatment were retrieved from online electronic PubMed and Web of Science databases.

RESULTS

This review highlighted the effects of five main active components in Astragali Radix including astragaloside Ⅳ, cycloastragenol, astragalus polysaccharide, calycosin-7-O-β-d-glucoside, and calycosin on CCVDs. The mechanisms mainly involved anti-oxidative damage, anti-inflammatory, and antiapoptotic through signaling pathways such as PI3K/Akt, Nrf2/HO-1, and TLR4/NF-κB pathway. In addition, the majority active constituents in AR have no obvious toxic side effects.

CONCLUSION

The main active components of Astragali Radix, especially AS-IV, have been extensively summarized. It has been proved that Astragali Radix has obvious therapeutic effects on various CCVDs, including myocardial and cerebral ischemia, hypertension, atherosclerosis, cardiac hypertrophy, chronic heart failure. CAG possesses anti-ischemia activity without toxicity, indicating a worthy of further development. However, high-quality clinical and pharmacokinetic studies are required to validate the current studies.

Apocynum Leaf Extract Suppresses the Progress of Atherosclerosis in Rats via the FKN/SYK/p38 Signal Pathway

To investigate the antiatherosclerotic effects of flavonoids extracted from Apocynum venetum (AVF) leaves in atherosclerotic rats and the underlying mechanisms, a total of 72 male Wistar rats were randomly divided into six groups: control group, model group, simvastatin group, low-dose AVF group, medium-dose AVF group, and high-dose AVF group. Atherosclerosis in rats was induced with a high-fat diet and an intraperitoneal injection of VD₃ once daily for three contiguous days at a total injection dose of 70 U/kg. At the end of the 13^th week, total serum cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) contents were measured. The hematoxylin-eosin (HE) staining was applied to evaluate the morphological changes. The ELISA method was used to detect related inflammatory factors and oxidative stress indicators. The corresponding protein expression and the mRNA level were detected by western blot analysis and reverse transcriptase PCR. HE staining showed that the thoracic aorta wall was thickened, and the aortic subendothelial foam cells and lipid vacuoles were reduced in the medium/high-AVF groups. Similarly, the TC, TG, LDL-C, and malondialdehyde (MDA) levels in the model group were significantly higher, but the HDL-C level and superoxide dismutase (SOD) activity were lower than those of the control group, and these effects were ameliorated by treatment with simvastatin or AVF. ELISA results showed that compared with the control group, the model group C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) results were significantly increased, and the medium AVF and high AVF could significantly reduce the expression of related inflammatory factors. The AVF inhibited intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin mRNA and related protein expression in the aorta in atherosclerotic rats. Western blot analysis also showed that AVF can significantly reduce the protein expression of fractalkine (FKN), spleen tyrosine kinase (SYK), and p38 mitogen-activated protein kinase (p38) in the rat aorta. We believe that the AVF can effectively reduce blood lipid levels in rats with atherosclerosis and delay atherosclerotic progression by inhibiting excessive inflammatory factors and inhibiting related adhesion factors. The underlying mechanism may be related to the FKN/SYK/p38 signaling pathway activity. Our results contribute to validating the traditional use of the Apocynum leaf extract in the treatment of atherosclerosis.

Comprehensive evaluation of two Astragalus species (A. campylosema and A. hirsutus) based on biological, toxicological properties and chemical profiling

Astragalus L. (Fabaceae) is an important genus with numerous species having various traditional medicinal uses making them of interest for scientific investigations to ascertain their therapeutic benefits. In the present study, the quantitative polyphenolic profiles of methanolic extracts from different parts (leaves, flowers, and roots) of two endemic Astragalus species growing in Turkey, i.e. A. campylosema Boiss. and A. hirsutus Vahl were determined, along with their antioxidant and enzyme inhibitory properties. A. campylosema and A. hirsutus extracts showed varying total phenolic (25.80-40.60 and18.59-29.46 mg GAE/g, respectively) and total flavonoid (11.21-105.91 and 16.06-131.91 mg RE/g, respectively) contents. HPLC-MS/MS revealed rutin to be the predominant phenolic compound in all the extracts of A. campylosema and leaf extract of A. hirsutus (133.53-752.42 μg g^-1), while hyperoside was the major one in the flower and root extracts of A. hirsutus (2014.07 and 123.13 μg g^-1, respectively). In DPPH and ABTS assays, radical scavenging capacity was demonstrated by all extracts of A. campylosema (47.13-48.10 and 87.03-115.36 mg TE/g, respectively) and A. hirsutus (17.82-38.67 and 47.84-57.29 mg TE/g, respectively). Reducing activity was also displayed by the extracts in CUPRAC and FRAP assays (A. campylosema: 83.06-135.20 and 59.15-90.19 mg TE/g, respectively; A. hirsutus: 53.02-83.42 and 31.25-43.25 mg TE/g, respectively). All extracts were also found to act as metal chelators (12.32-21.45 mg EDTAE/g) and exhibited total antioxidant capacity ranging from 1.16 to 1.60 mmol TE/g, in phosphomolybdenum assay. Acetyl- and butyryl-cholinesterase inhibitory effects were observed by all the extracts of the two species (1.56-4.99 mg GALAE/g). Anti-hyperpigmentation potential by inhibiting tyrosinase (54.55-67.35 mg KAE/g) was reported as well. Carbohydrate hydrolyzing enzymes, amylase and glucosidase were also inhibited (0.22-1.03 mmol ACAE/g). Overall, A. campylosema extracts showed relatively better antioxidant and enzyme inhibitory potentials compared to A. hirsutus extracts. Strikingly, A. hirsutus extracts was found to have higher AGE inhibition activity than A. campylosema. Although the cytotoxic effect of three different organs obtained from A. campylosema and A. hirsutus increased depending on the dose (from 10 to 200 μg/mL), it was found that both plant extracts did not show a genotoxic effect at the highest concentration of 200 μg/mL. Indeed, data amassed from this current scientific work showed the two selected Astragalus species to be rich in bioactive polyphenols that could be responsible for the various pharmacological activities and hence demands to be further explored for their possible applications as natural health promoting agents.

Phytochemistry and cardiovascular protective effects of Huang-Qi (Astragali Radix)

Huang-Qi (Astragali Radix) is an herbal tonic widely used in China and many other countries. It is derived from the roots of Astragalus membranaceus and A. membranaceus var. mongholicus and shows potent cardiovascular protective effects. In this article, we comprehensively reviewed 189 small molecules isolated from the two Astragalus species and discussed the interspecies chemical differences. Moreover, we summarized the pharmacological activities and mechanisms of action of Huang-Qi and its major bioactive compounds for the treatment of cardiovascular diseases. This review covers 171 references published between February 1983 and March 2020.

Effect of honey and insulin treatment on oxidative stress and nerve conduction in an experimental model of diabetic neuropathy Wistar rats

Diabetic neuropathy is the most common complication affecting more than 50% of patients with longstanding diabetes. Till date, there are no reports to explain the scientific basis of alternative medicine as an adjunct therapy for treating diabetic neuropathy. Hence, we studied the effect of honey and insulin treatment on hyperglycemia, dyslipidemia, oxidant and anti-oxidant status and nerve conduction in experimental diabetic neuropathy Wistar rats. In this experimental study, forty healthy male Wistar albino rats of 10-12 weeks age, weighing between 150 to 200g were obtained from our institute central animal house. After acclimatization, the rats were divided into control (n = 8) and experimental (n = 32) groups randomly. In the experimental group, type 2 diabetic neuropathy was induced with high fat and high sugar diet for 8 weeks followed by streptozotocin at a dose of 35 mg/kg body weight. Three days after streptozotocin injection, blood glucose levels of rats were measured from fasting samples to confirm diabetes. After the development of diabetes, rats were given standard rodent chow and allowed four more weeks to remain diabetic and to develop neuropathy. Every second week, nerve conduction study was done to confirm neuropathy. All the diabetic rats of experimental group developed neuropathy after 4 weeks of developing diabetes, which was confirmed by significant reduction in conduction velocity of sensory and motor nerve when compared to non-diabetic control group. After the development of neuropathy, these rats were randomly divided into diabetic neuropathy with no treatment group (n = 8) and three treatment groups (n = 8, each). The rats of treatment group were administered with either honey or insulin or honey+insulin for six weeks. After six-weeks of intervention, there was significant decrease in blood glucose and lipids in honey, insulin and honey+insulin treated neuropathy rats, when compared with no treatment group. Malondialdehyde was reduced and total anti-oxidant status improved in all the three treatment groups. There was no significant increase in conduction velocity of sciatic tibial motor nerve in treatment groups when compared with no treatment group. However, the sensory nerve conduction velocity improved significantly in honey+insulin treated neuropathy rats. In conclusion, six-week honey treatment helped in reducing dyslipidemia and oxidative stress. Honey given along with insulin for six-weeks improved sensory nerve conduction velocity in experimental diabetic neuropathy Wistar rats.

Exploring the In Vivo Existence Forms (23 Original Constituents and 147 Metabolites) of Astragali Radix Total Flavonoids and Their Distributions in Rats Using HPLC-DAD-ESI-IT-TOF-MSn

Astragali Radix total flavonoids (ARTF) is one of the main bioactive components of Astragali Radix (AR), and has many pharmacological effects. However, its metabolism and effective forms remains unclear. The HPLC-DAD-ESI-IT-TOF-MSⁿ technique was used to screen and tentatively identify the in vivo original constituents and metabolites of ARTF and to clarify their distribution in rats after oral administration. In addition, modern chromatographic methods were used to isolate the main metabolites from rat urine and NMR spectroscopy was used to elucidate their structures. As a result, 170 compounds (23 original constituents and 147 metabolites) were tentatively identified as forms existing in vivo, 13 of which have the same pharmacological effect with ARTF. Among 170 compounds, three were newly detected original constituents in vivo and 89 were new metabolites of ARTF, from which 12 metabolites were regarded as new compounds. Nineteen original constituents and 65 metabolites were detected in 10 organs. Four metabolites were isolated and identified from rat urine, including a new compound (calycoisn-3'-O-glucuronide methyl ester), a firstly-isolated metabolite (astraisoflavan-7-O-glucoside-2'-O-glucuronide), and two known metabolites (daidzein-7-O-sulfate and calycosin-3'-O-glucuronide). The original constituents and metabolites existing in vivo may be material basis for ARTF efficacy, and these findings are helpful for further clarifying the effective forms of ARTF.

7-O-methylpunctatin, a Novel Homoisoflavonoid, Inhibits Phenotypic Switch of Human Arteriolar Smooth Muscle Cells

Remodeling of arterioles is a pivotal event in the manifestation of many inflammation-based cardio-vasculopathologies, such as hypertension. During these remodeling events, vascular smooth muscle cells (VSMCs) switch from a contractile to a synthetic phenotype. The latter is characterized by increased proliferation, migration, and invasion. Compounds with anti-inflammatory actions have been successful in attenuating this phenotypic switch. While the vast majority of studies investigating phenotypic modulation were undertaken in VSMCs isolated from large vessels, little is known about the effect of such compounds on phenotypic switch in VSMCs of microvessels (microVSMCs). We have recently characterized a novel homoisoflavonoid that we called 7-O-methylpunctatin (MP). In this study, we show that MP decreased FBS-induced cell proliferation, migration, invasion, and adhesion. MP also attenuated adhesion of THP-1 monocytes to microVSMCs, abolished FBS-induced expression of MMP-2, MMP-9, and NF-κB, as well as reduced activation of ERK1/2 and FAK. Furthermore, MP-treated VSMCs showed an increase in early (myocardin, SM-22α, SM-α) and mid-term (calponin and caldesmon) differentiation markers and a decrease in osteopontin, a protein highly expressed in synthetic VSMCs. MP also reduced transcription of cyclin D1, CDK4 but increased protein levels of p21 and p27. Taken together, these results corroborate an anti-inflammatory action of MP on human microVSMCs. Therefore, by inhibiting the synthetic phenotype of microVSMCs, MP may be a promising modulator for inflammation-induced arteriolar pathophysiology.

The effect of different types of honey on the lipid profile of streptozotocin-induced diabetic rats

INTRODUCTION

The effect of honey consumption in diabetic patients has been contradictory. The aim of the present animal study was to compare the effect of different types of honey on the lipid profile in diabetic rats.

MATERIAL AND METHODS

Sixty-four male Wistar rats were divided into two main groups: a streptozotocin-induced diabetes mellitus (DM) group (including four subgroups) and a healthy group (including four subgroups), based on random allocation. Three subgroups of each main group were given 1 mg/kg of three different types of honey (acacia, astragalus, and artificial honey) by oral gavage for 10 weeks. The control groups were given distilled water. Blood samples were collected, and the lipid profile was measured and compared between the eight groups after the intervention.

RESULTS

The levels of LDL, triglycerides (TG), and total cholesterol (Tchol) in DM rats treated with astragalus honey were significantly lower and the HDL level was significantly higher compared to the other DM and healthy groups (all p-values < 0.05). LDL, TG, and Tchol levels in DM rats treated with artificial honey were significantly higher, and HDL levels were significantly lower than for other types of honey and for the control groups (all p-values < 0.05). LDL, HDL, TG, and Tchol levels in healthy rats were not significantly different between the groups (p-value > 0.05).

CONCLUSIONS

Different types of honey (acacia, astragalus, and artificial honey) had various effects on serum lipid profiles in diabetic rats. The results of this study indicated that the effect of honey on diabetic patients can vary widely based on its source.

A Systematic Review of Phytochemistry, Pharmacology and Pharmacokinetics on Astragali Radix: Implications for Astragali Radix as a Personalized Medicine

Astragali radix (AR) is one of the most widely used traditional Chinese herbal medicines. Modern pharmacological studies and clinical practices indicate that AR possesses various biological functions, including potent immunomodulation, antioxidant, anti-inflammation and antitumor activities. To date, more than 200 chemical constituents have been isolated and identified from AR. Among them, isoflavonoids, saponins and polysaccharides are the three main types of beneficial compounds responsible for its pharmacological activities and therapeutic efficacy. After ingestion of AR, the metabolism and biotransformation of the bioactive compounds were extensive in vivo. The isoflavonoids and saponins and their metabolites are the major type of constituents absorbed in plasma. The bioavailability barrier (BB), which is mainly composed of efflux transporters and conjugating enzymes, is expected to have a significant impact on the bioavailability of AR. This review summarizes studies on the phytochemistry, pharmacology and pharmacokinetics on AR. Additionally, the use of AR as a personalized medicine based on the BB is also discussed, which may provide beneficial information to achieve a better and more accurate therapeutic response of AR in clinical practice.

Natural plant products in treatment of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe disease characterized by progressive remodeling of distal pulmonary arteries and persistent elevation of pulmonary vascular resistance (PVR), which leads to right ventricular dysfunction, heart failure, and eventually death. Although treatment responsiveness for this disease is improving, it continues to be a life-threatening condition. With the clinical efficacy of natural plant products being fully confirmed by years of practice, more and more recognition and attention have been obtained from the international pharmaceutical industry. Moreover, studies over the past decades have demonstrated that drugs derived from natural plants show unique advantages and broad application prospects in PAH treatment, not to mention the historical application of Chinese traditional medicine in cardiopulmonary diseases. In this review, we focus on summarizing natural plant compounds with therapeutic properties in PAH, according to the extracts, fractions, and pure compounds from plants into categories, hoping it to be helpful for basic research and clinical application.

Evaluation of the Pharmaceutical Properties and Value of Astragali Radix

Astragali Radix (AR), a Chinese materia medica (CMM) known as Huangqi, is an important medicine prescribed in herbal composite formulae (Fufang) by Traditional Chinese medicine (TCM) practitioners for thousands of years. According to the literature, AR is suggested for patients suffering from “Qi”- and “Blood”-deficiencies, and its clinical effects are reported to be related to anti-cancer cell proliferation, anti-oxidation, relief of complications in cardiovascular diseases, etc. The underlying cell signaling pathways involved in the regulation of these various diseases are presented here to support the mechanisms of action of AR. There are two botanical sources recorded in China Pharmacopoeia (CP, 2015): Astragalus membranaceus (Fisch.) Bge. Var. mongohlicus, (Bge.) Hsiao, and Astragalus membranaceus (Fisch.) Bge. (Fam. Leguminosae), whose extracts of dried roots are processed via homogenization-assisted negative pressure cavitation extraction. Geographic factors and extraction methods have impacts on the pharmaceutical and chemical profiles of AR. Therefore, the levels of the major bioactive constituents of AR, including polysaccharides, saponins, and flavonoids, may not be consistent in different batches of extract, and the pharmaceutical efficacy of these bioactive ingredients may vary depending on the source. Therefore, the present review mainly focuses on the consistency of the available sources of AR and extracts and on the investigation of the biological functions and mechanisms of action of AR and of its major bioactive constituents. Furthermore, it will also include a discussion of the most popular AR composite formulae to further elucidate their chemical and biological profiles and understand the pharmaceutical value of AR.

Anti-Aging Implications of Astragalus Membranaceus (Huangqi): A Well-Known Chinese Tonic

Owing to a dramatic increase in average life expectancy and the Family Planning program of the 1970s - 1990s, China is rapidly becoming an aging society. Therefore, the investigation of healthspan-extending drugs becomes more urgent. Astragalus membranaceus (Huangqi) is a major medicinal herb that has been commonly used in many herbal formulations in the practice of traditional Chinese medicine (TCM) to treat a wide variety of diseases and body disorders, or marketed as life-prolonging extracts for human use in China, for more than 2000 years. The major components of Astragalus membranaceus are polysaccharides, flavonoids, and saponins. Pharmacological research indicates that the extract component of Astragalus membranaceus can increase telomerase activity, and has antioxidant, anti-inflammatory, immunoregulatory, anticancer, hypolipidemic, antihyperglycemic, hepatoprotective, expectorant, and diuretic effects. A proprietary extract of the dried root of Astragalus membranaceus, called TA-65, was associated with a significant age-reversal effect in the immune system. Our review focuses on the function and the underlying mechanisms of Astragalus membranaceus in lifespan extension, anti-vascular aging, anti-brain aging, and anti-cancer effects, based on experimental and clinical studies.

Total flavonoids from Astragalus alleviate endothelial dysfunction by activating the Akt/eNOS pathway

Objective

To investigate the vasodilative and endothelial-protective effects and the underlying mechanisms of total flavonoids from Astragalus (TFA).

Methods

The vasodilative activities of TFA were measured with a myograph ex vivo using rat superior mesenteric arterial rings. The primary human umbilical vein endothelial cell (HUVEC) viabilities were assayed using the cell counting kit-8 after hypoxia or normoxia treatment with or without TFA. Akt, P-Akt, eNOS, P-eNOS, Erk, P-Erk, Bcl-2 and Bax expression were analyzed using western blotting.

Results

TFA showed concentration-dependent vasodilative effects on rat superior mesenteric arterial rings, but had no effects on normal or potassium chloride precontracted arterial rings. TFA did not affect HUVEC viabilities in normoxia, but dramatically promoted cell proliferation in the concentration range of 1 to 30 µg/mL under hypoxia. Moreover, TFA significantly increased the ratios of P-Akt/Akt and P-eNOS/eNOS in vascular endothelial cells under hypoxic conditions, but did not change the P-Erk/Erk or Bcl-2/Bax ratios.

Conclusions

TFA might exhibit vasorelaxant and endothelial-protective effects via the Akt/eNOS signaling pathway.

Vascular protective effects of Astragalus membranaceus and its main constituents in rats with chronic hyperhomocysteinemia

Hyperhomocysteinemia (HHcy) is an important factor in cardiovascular disease. However, is currently no cure available in western medicine for HHcy-evoked cardiovascular disease. The present study explored the vascular protective effects of Astragalus membranaceus (AM), a traditional Chinese medicine. Rats with HHcy were induced by feeding high-methionine diets and treated with total extract of AM (TEA) and its constituents, including Astragalus saponins (ASP), Astragalus total flavonoids (ATF) and Astragalus polysaccharides (APS). Examination of the rats indicated that TEA and ASP controlled blood pressure and ameliorated HHcy-induced impairment of endothelium-dependent vasorelaxation by increasing the nitric oxide content and nitric oxide synthase activity of the abdominal aorta. Furthermore, they decreased the accumulation of hydrogen peroxide and superoxide anion, and attenuated the inhibition of superoxide dismutase and catalase activities in rats with HHcy. Additionally, TEA and ASP attenuated the HHcy-induced increases of matrix metalloproteinase (MMP)-2 and -9 concentrations. However, similar effects were not observed for ATF and APS. In conclusion, TEA and ASP are beneficial to vascular disease, and their effects may be attributed to protective actions against oxidation, activity of the MMPs and endothelial dysfunction.

Protective effects of total flavonoids of Astragalus against adjuvant-induced arthritis in rats by regulating OPG/RANKL/NF-κB pathway

BACKGROUND

Astragalus membranaceus Bunge is one of the oldest and most frequently used crude herbs in traditional Chinese medicine. The total flavonoids of Astragalus (TFA) are the main active components isolated from Astragalus membranaceus Bunge. Our recent study has shown its potential immunomodulatory and anti-inflammatory effects in vivo and in vitro. However, its anti-arthritic effects and mechanisms of action involved have not been elucidated. The aim of this study was to evaluate the protective effects and possible mechanisms of TFA on Freund's complete adjuvant (FCA)-induced arthritis in rats.

METHODS

Wistar rats were intradermally injected FCA into the right hind metatarsal footpads to establish adjuvant-arthritic model. The rats were intragastrically administered daily with TFA at 25, 50 and 100mg/kg for 28days after FCA induction. Body weight, primary paw swelling, arthritis index, thymus and spleen indices were measured. The levels of serum tumor necrosis factor (TNF)-α, interleukin (IL)-1β, prostaglandin (PG)E₂, osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were determined using ELISA. Histopathological changes and scores in joint tissues were examined using hematoxylin and eosin (H&E). The expression of nuclear factor (NF)-κB p65 in synovial tissues was assayed using immunohistochemical method.

RESULTS

TFA significantly increased body weight, attenuated primary paw swelling and arthritis index, decreased thymus and spleen indices of rats induced by FCA. Furthermore, TFA significantly inhibited serum TNF-α, IL-1β, PGE₂ and RANKL production, and promoted serum OPG production and OPG/RANKL ratio of rats induced by FCA. Histopathological examination indicated that TFA significantly attenuated inflammatory cell infiltration, synovial hyperplasia, pannus formation, and bone and cartilage damage. Immunohistochemical assay indicated that TFA inhibited NF-κB p65 expression in synovial tissues of rats induced by FCA.

CONCLUSIONS

These results suggest that TFA exerts potential protective effects against FCA-induced arthritis in rats by regulating OPG/RANKL/NF-κB pathway.

IN VIVO AND IN VITRO IMMUNOMODULATORY AND ANTI-INFLAMMATORY EFFECTS OF TOTAL FLAVONOIDS OF ASTRAGALUS

Background:

Astragali Radix has long been used to improve immune function in traditional Chinese medicine. However, its main active components and potential immunomodulatory or anti-inflammatory activities have not been elucidated. In the present study, the immunomodulatory and anti-inflammatory activities of total flavonoids of Astragalus (TFA) isolated from Astragali Radix were evaluated by using in vivo animal models and in vitro cell models.

Materials and Methods:

The in vivo Immunomodulatory and anti-inflammatory activities of TFA were assessed by measuring macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, ear edema test in mice, paw edema test in rats, vascular permeability test in mice and granuloma test in rats. The in vitro Immunomodulatory and anti-inflammatory activities of TFA were assessed by examining its effect on cytokine and mediator production in un-stimulated and LPS-stimulated murine RAW 264.7 macrophages.

Results:

The results of in vivo experiments showed that TFA enhanced macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, and attenuated mouse ear edema, rat paw edema, mouse vascular permeability and rat granuloma formation. The results of in vitro experiments showed that TFA stimulated the production of NO and cytokine TNF-α, IL-Ιβ, IL-6 and IFN-γ in un-stimulated RAW 264.7 macrophages, and inhibited the overproduction of these inflammatory mediators in LPS-stimulated RAW 264.7 macrophages in a dose-dependent manner without exerting cytotoxicity.

Conclusion:

These results of this study indicate that TFA have potential immunostimulatory and anti-inflammatory effects.

Components of Boiogito Suppress the Progression of Hypercholesterolemia and Fatty Liver Induced by High-Cholesterol Diet in Rats

BACKGROUND

Ogi, one main component of boiogito (BOT), is reported to have an effect on hypercholesterolemia and NAFLD. In this experiment, we examined effects of ogi on the progression of hypercholesterolemia and fatty liver induced by high-cholesterol diet in rats and compared with the effects of ogi combined with ginger or hesperidin.

METHODS

Hypercholesterolemia and fatty liver were induced by a high cholesterol diet in rats. Extract of ogi, ogi with hesperidin, and ogi with ginger were added to the high-cholesterol diet, respectively. Ezetimibe was also added to the high-cholesterol diet as a positive control. After 6 and 12 weeks, body, liver and adipose tissue weights, blood chemistry, lipid-related and inflammatory-related factors were examined.

RESULTS

The high cholesterol diet increased body, liver and adipose tissue weights, and serum cholesterol concentrations. Ogi, ogi with hesperidin or ginger and ezetimibe improved them. In the histological examinations, we observed a significant improvement after treatment. The lipid-related factors (RBP4, HFABP and CFABP) were improved by treatment. Biomarkers of cholesterol synthesis (lathosterol) and absorption (campesterol, beta-sitosterol) were lower in the treatment groups. Inflammatory-related factors (MCP1, CCR2 and TNF-alpha) and ICAM-1 were ameliorated after treatment, especially by ogi with ginger.

CONCLUSION

Ogi, ogi with hesperidin or ginger have a similar effect of BOT and ezetimibe on hypercholesterolemia and fatty liver. Ogi with ginger reveals a stronger additive effect with no significant difference. However, as for the anti-inflammatory (MCP1, CCR2 and TNF-alpha) and anti-arteriosclerotic (ICAM-1) effects, additive effects of ogi with ginger are more potent than that of ogi alone or ezetimibe.

Flavonoids from the Genus Astragalus: Phytochemistry and Biological Activity

Flavonoids, the most common plant polyphenols are widely distributed in every species and possess a broad range of pharmacological activities. The genus Astragalus is the largest in the Fabaceae family with more than 2,500 species spread. They are known to contain different metabolites such as flavonoids, saponins, and polysaccharides. Plants from the genus have been used in the traditional medicine of many countries for centuries. This paper is focused on the large group of flavonoid compounds. Details on structure as well as information about the pharmacological properties of flavonoids, isolated from Astragalus species have been discussed. This review is based on publications until the first half of 2014 and includes also the results from our phytochemical investigations of the genus.

Recent advances in biosynthesis of bioactive compounds in traditional Chinese medicinal plants

Plants synthesize and accumulate large amount of specialized (or secondary) metabolites also known as natural products, which provide a rich source for modern pharmacy. In China, plants have been used in traditional medicine for thousands of years. Recent development of molecular biology, genomics and functional genomics as well as high-throughput analytical chemical technologies has greatly promoted the research on medicinal plants. In this article, we review recent advances in the elucidation of biosynthesis of specialized metabolites in medicinal plants, including phenylpropanoids, terpenoids and alkaloids. These natural products may share a common upstream pathway to form a limited numbers of common precursors, but are characteristic in distinct modifications leading to highly variable structures. Although this review is focused on traditional Chinese medicine, other plants with a great medicinal interest or potential are also discussed. Understanding of their biosynthesis processes is critical for producing these highly value molecules at large scale and low cost in microbes and will benefit to not only human health but also plant resource conservation.

Review of the use of botanicals for epilepsy in complementary medical systems--Traditional Chinese Medicine

In traditional Chinese medicine, botanical remedies have been used for centuries to treat seizures. This review aimed to summarize the botanicals that have been used in traditional Chinese medicine to treat epilepsy. We searched Chinese online databases to determine the botanicals used for epilepsy in traditional Chinese medicine and identified articles using a preset search syntax and inclusion criteria of each botanical in the PubMed database to explore their potential mechanisms. Twenty-three botanicals were identified to treat epilepsy in traditional Chinese medicine. The pharmacological mechanisms of each botanical related to antiepileptic activity, which were mainly examined in animal models, were reviewed. We discuss the use and current trends of botanical treatments in China and highlight the limitations of botanical epilepsy treatments. A substantial number of these types of botanicals would be good candidates for the development of novel AEDs. More rigorous clinical trials of botanicals in traditional Chinese medicine for epilepsy treatment are encouraged in the future. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

Potential quality evaluation method for Radix Astragali based on sweetness indicators

Sweetness is a traditional sensory indicator used to evaluate the quality of the popular Chinese herb Radix Astragali (RA). RA roots with strong sweetness are considered to be of good quality. However, neither a thorough analysis of the component(s) contributing to RA sweetness, nor a scientific investigation of the reliability of this indicator has been conducted to date. In this study, seven kinds of sweetness components were identified in RA and a quality evaluation method based on these components was established and used to characterize the quality of 48 RA samples. The sweetness evaluation method of RA was first built based on the sweetness components, and a comprehensive evaluation index commonly used in quality control of RA was also derived, which was based on the contents of four indicators (astragaloside IV, calycosin glucoside, polysaccharides and extracts). After evaluating the correlation of these indexes the results showed that the level of sweetness exhibited a strong positive correlation with the proposed comprehensive index. Our results indicate that sweetness is one of the most important quality attributes of RA and thus provide a scientific basis for the utility of the sweetness indicator in quality assessment of this Chinese herb.

Bu-shen-he-mai-fang (HMF) Decoction Inhibits Atherosclerosis by Improving Antioxidant and Anti-Inflammatory Activities in ApoE-deficient Mice

OBJECTIVE

To observe the effects of Bu-shen- he- mai- fang (HMF) on experimental atherosclerosis in ApoE-deficient mice.

MATERIALS AN METHODS

Thirty male ApoE-deficient mice were randomly divided into 3 groups (10 mice per group) as follows: one group received the standard high- cholesterol diet (high- cholesterol group, HC); Another group received high- cholesterol diet supplemented with HMF decoction 1.37 g/kg/day; the third group received a high- cholesterol diet, supplemented with atrovastatin 5 mg/kg/day for 8 weeks. The extent of atherosclerosis, the expression of LOX-1 protein and macrophage infiltration were evaluated by H&E, oil red O staining, and immunohistochemical staining. SOD was also measured by a spectrophotometer.

RESULTS

The degree of atherosclerosis was significantly lower in HMF group and atrovastatin group than that in high-cholesterol group. The expression of LOX-1 protein and macrophage filtration were significantly lower in HMF group and atrovastatin group than that in high-cholesterol group. Also, the SOD was higher in HMF group and atrovastatin group than that in high-cholesterol group.

CONCLUSION

The results suggested that HMF significantly inhibited early atherosclerotic lesions by inhibiting inflammatory response and decreasing the generation of ROS.

Effects of kampo formulas on the progression of hypercholesterolemia and Fatty liver induced by high-cholesterol diet in rats

BACKGROUND

Bofutsushosan is a well known Kampo, traditional Japanese medicine, based on ancient Chinese medicine mainly used in the treatment of hypercholesterolemia in Japan. We selected two Kampo formulas, Boiogito and Keishibukuryogan mainly used in the treatment of hypercholesterolemia in China to compare with Bofutsushosan and cholesterol absorption inhibitor ezetimibe.

METHODS

Hypercholesterolemia and fatty liver were induced by high cholesterol (containing 2% cholesterol and 0.5% cholic acid) diet in male Wistar rats for 6 and 12 weeks. Kampo formulas Boiogito, Bofutsushosan, Keishibukuryogan and ezetimibe were added to the high-cholesterol diet, respectively. After 6 and 12 weeks, body and liver weights, blood chemistry, cholesterol concentrations, fat-related and inflammatory-related factors were examined.

RESULTS

High-cholesterol diet increased body and liver weights, and serum cholesterol concentrations. Boiogito and ezetimibe improved them. Serum ICAM-1 and RBP4 were increased in the high cholesterol diet group. Boiogito and ezetimibe improved them too. In the histological examinations of liver and adipose tissues, we observed a significant improvement after treatment. Immunostaining expression of ICAM-1 in aorta was improved by Boiogito, Bofutsushosan, Keishibukuryogan and ezetimibe. The mRNA expression of RBP4, HFABP, CFABP, MCP1 and CCR2 in liver and adipose tissue were decreased by Boiogito and ezetimibe.

CONCLUSION

Boiogito has a protective effect on the progression of hypercholesterolemia and fatty liver induced by high-cholesterol diet in rats and more effective than Bofutsushosan and Keishibukuryogan. The lipid-lowering effect of Boiogito is not stronger than ezetimibe. But the anti-inflammatory (MCP1, CCR2) and anti-arteriosclerotic (ICAM-1) effects of Boiogito are more potent than ezetimibe.

A review of recent research progress on the astragalus genus

Astragalus L., is one of the largest genuses of flowering plants in the Leguminosae family. Roots of A. membranaceus Bge. var. mongholicus (Bge.) Hsiao, A. membranaceus (Fisch.) Bge. and its processed products are listed in the China Pharmacopeia for “qi deficiency” syndrome treatment. However, more and more researches on other species of Astragalus have been conducted recently. We summarize the recent researches of Astragalus species in phytochemistry and pharmacology. More than 200 constituents, including saponins and flavonoids, obtained from 46 species of Astragalus genus were collected for this article. In pharmacological studies, crude extracts of Astragalus, as well as isolated constituents showed anti-inflammatory, immunostimulant, antioxidative, anti-cancer, antidiabetic, cardioprotective, hepatoprotective, and antiviral activities. The goal of this article is to provide an overview of chemical and pharmacological studies on the Astragalus species over the last 10 years, which could be of value to new drug or food supplement research and development.

Effects of Xin-Ji-Er-Kang formula on 2K1C-induced hypertension and cardiovascular remodeling in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Xin-Ji-Er-Kang (XJEK), a Chinese herbal formula, is effective against hypertension induced coronary heart disease, viral myocarditis and toxic myocarditis. In this study, the effect of XJEK on cardiovascular system was investigated. To test the hypothesis that Xin-Ji-Er-Kang (XJEK) has an anti-hypertensive effect mediated through attenuation of cardiac remodeling, and amelioration of vascular endothelial dysfunction and oxidative stress.

MATERIALS AND METHODS

Hypertension was induced in Wistar rats by 2 kidney 1 clip (2K1C) treatment. The hypertensive rats were then randomly assigned into four groups and treated as follows: group 1 (Sham-operated [Sh-Op] group received only drinking water), group 2 (induced hypertensive model+no treatment), and group 3 (induced hypertensive+a single daily oral dose of 24 g kg(-1) XJEK treatment) and group 4 (induced hypertensive+a single oral dose of 15 mg kg(-1) Fosinopril treatment). The rats in all the defined groups were respectively treated for a period of 4 weeks. Cardiovascular parameter such as systolic blood pressure (SBP) was measured weekly by using tail-cuff apparatus; left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP) and the rate of the rise in left ventricular pressure (±dp/dt max) were measured by using a PowerLab 8/30 apparatus (AD Instruments, Australia) at the end of the 8th week; heart weight/body weight (HW/BW) was determined as an index of myocardial hypertrophy (MH). Hematoxylin and eosin (H&E) and Van Gieson (VG) stain were used to assess the cardio-histological changes. Colorimetric analysis was used to assay serum superoxide dismutase (SOD) activity, malondialdehyde (MDA), nitric oxide (NO), and hydroxyproline (Hyp) contents in cardiac tissue. Angiotensin II (Ang II) content in serum was assessed by radioimmunoassay; tetrahydrobiopterin (BH4) content in cardiac tissue, BNP and endothelial NOS (eNOS) in serum were determined by using ELISA, and the protein expressions of c-Jun NH2-terminal kinase (JNK), P-JNK, p38, P-p38, and NADPH oxidases-2 (Nox-2) were measured by western blot.

RESULTS

XJEK therapy could impair the heart systolic and diastolic function, potently improve the heart weight index, inhibit the elevation of HW/BW ratio, and markedly ameliorate hemodynamic indices and vascular remodeling index. It has blunted the decrease of SOD, NO and the increase in MDA and Ang II serum contents, myocardial cross-section area (CSA), collagen volume fraction (CVF) and perivascular circumferential collagen area (PVCA) compared to the hypertensive model group. It also reduced the serum content of Hyp while increased BH4 levels in cardiac tissue. In addition, the expressions of Nox-2, P-JNK and P-p38MAPK were all suppressed compared to the hypertensive model group. Moreover, treatment with XJEK improved endothelial dysfunction (ED) manifested by promoting eNOS activities and enhancing the NO activity in serum.

CONCLUSION

The results of the present study show that XJEK attenuates 2K1C-induced hypertension in rats, which confirms our hypothesis that XJEK has an anti-hypertensive and cardiovascular remodeling effect via attenuation of cardiac remodeling and improvement of endothelial dysfunction and oxidative stress.

Pharmaceutical properties of calycosin, the major bioactive isoflavonoid in the dry root extract of Radix astragali

CONTEXT

Radix astragali (Fabaceae astragalus propinquus Schischkin) is a Chinese medicinal herb traditionally used for the treatment of several diseases. Calycosin is the major bioactive chemical in the dry root extract of this medical plant.

OBJECTIVE

This work presents a brief overview of recent reports on the potential effects of calycosin on several diseases and the possible mechanisms of action of this chemical.

MATERIALS AND METHODS

This review gathers information from the scientific literature (before 1 June 2013) that was compiled from various databases, such as Science Direct, PubMed, Google Scholar, and Scopus.

RESULTS

The potential pharmaceutical properties of calycosin in the treatment of tumors, inflammation, stroke, and cardiovascular diseases have gained increasing attention in the recent years. The literature survey showed that calycosin exhibits promising effects for the treatment of several diseases and that these effects may be due to its isoflavonoid and phytoestrogenic properties. The effects of calycosin most likely result from its interaction with the ER receptors on the cell membrane and the modulation of the MAPK signaling pathway.

CONCLUSION

Calycosin exhibits great potential as a therapeutic drug and may be a successful example of the standardization and modernization of traditional Chinese herbal medicine.

Benefical therapeutic effect of Chinese Herbal Xinji'erkang formula on hypertension-induced renal injury in the 2-kidney-1-clip hypertensive rats

BACKGROUND

Increase in evidence shows that the role of kidney injury in hypertension is important. Xinji'erkang (XJEK), a Chinese herbal formula, has been identified as an effective preparation in the treatment of coronary heart disease and myocarditis. We have previously demonstrated that XJEK attenuate oxidative stress and hypertension target organ damage. The aim of this study was to assess the renal protective function of XJEK.

MATERIALS AND METHODS

Two Kidney One Clip (2K1C) model was adopted to induce hypertension in rats. We submitted male Sprague Dawley (150-180) g rats to either renal artery clipping or sham operation. Renal hypertension was established after four weeks of surgery. Rats were randomized divided into the four groups: sham-operated group (Sh-Op) (n=10), two-kidney, one-clip hypertension group (2K1C) (n=10), Xinji'erkang treatment group (XJEK) (n=10) and Fosinopril (n=10) treatment group. Drugs were administered orally daily for four weeks. Systolic pressures were measured every week using the tail-cuff apparatus. 24h before death, urine samples were collected for detect of urinary proteins. The kidney weight (KW) index was expressed as kidney weight/body weight (KW/BW). The histological changes were investigated by hematoxylin and eosin and Van Gieson staining. Immunohistochemical assay was employed to observe the intra-renal transforming growth factor-β1 (TGF-β1) protein expression. Serum creatinine (SCR) and blood urea nitrogen (BUN) were assayed by automatic biochemical analyzer. ELISA kit was used to assay Angiotensin II (Ang II) and TGF-β1 content in serum.

RESULTS

Administration of XJEK markedly alleviated the rise in blood pressure and declined LKW/BW ratio. Histo-pathological injuries including hypertrophic glomerular, glomerular sclerosis, glomerular and interstitial fibrosis were attenuated. XJEK also decreased SCR, BUN, urinary proteins in 24h urine, serum Ang II and TGF-β1 concentrations and the intra-renal TGF-β1 protein expression.

CONCLUSION

XJEK therapy in the 2K1C hypertensive rats affects the rise in blood pressure and ameliorates the severity of kidney injury. The protective effect is most likely due to the ability of XJEK to affect the Renin-Angiotensin-Aldosterone System (RAAS) and the TGF-β systems.

Comparative anti-inflammatory and hepatoprotective activities of Astragalus gummifer Labill herb and roots in rats

BACKGROUND

The Astragalus gummifer (F. Fabaceae), herb and roots were studied for anti-inflammatory and hepatoprotective activities.

MATERIALS AND METHOD

The alcoholic extracts of Astragalus gummifer (F. Fabaceae), herb (AGHE), and roots (AGRE), were used for anti-inflammatory and hepatoprotective activities in Wister rats. The effects of AGHE and AGRE were compared with the standard drugs Phenylbutazone and silymarin, for anti-inflammatory and hepatoprotective activities respectively.

RESULT

Both extracts showed significant anti-inflammatory activity (P< 0.001). AGRE showed comparatively more significant hepatoprotective activity (P< 0.001), than AGHE (P< 0.05); at doses of 250 and 500 mg/kg body weight as manifested by lowering the serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and total bilirubin. The hepatoprotective activity was, also, supported by total protein (TP), malondialdehyde (MDA), nonprotein sulfhydryls (NP-SH), and histo-pathological studies of liver tissue.

DISCUSSION

To the best of our knowledge, this is the first report of the anti-inflammatory and hepatoprotective activities of Astragalus gummifer. The results of present studies indicated that both AGHE and AGRE can be used in inflammatory conditions, while investigation supports the use of AGRE in cases that hepatoprotection are required in the hepatotoxic conditions. More supportive studies are required before clinical recommendation.

Effects of traditional Chinese medicine Xin-Ji-Er-Kang formula on 2K1C hypertensive rats: role of oxidative stress and endothelial dysfunction

Background

XinJiErKang (XJEK), a Chinese herbal formula, is identified as an effective preparation to treat coronary heart disease and myocarditis. The aim of the study is to investigate the anti-hypertensive effects of XJEK by oral administration and also to find out whether the drug has any role in oxidative stress and vascular endothelial function.

Methods

Clipping of the renal artery resulted in gradual elevation of the systolic blood pressure (SBP) which reached a plateau after 4 weeks of surgery. Treatment of hypertensive rats (20 mmHg higher than basic systolic blood pressure) with XJEK (6, 12, 24 g/kg/day) and fosinopril (15 mg/kg/day) respectively by intragastric administration started 4 weeks after surgery and continued for 4 weeks. The sham-operated (Sh-Op) controls received drinking water. BP was monitored weekly using tail-cuff apparatus. At the end of 8 wk, left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), rate of rise of left ventricular pressure (±dp/dtmax) were examined (PowerLab 8/30, AD Instruments, Australia). The myocardial hypertrophy index was expressed as heart weight/body weight (HW/BW), the histological changes were investigated by hematoxylin and eosin (HE) and Van Gieson (VG) stain. Endothelium-dependent relaxations due to acetylcholine were observed in isolated rat thoracic aortic ring preparation. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) and nitric oxide (NO) content in serum, contents of hydroxyproline (Hyp) in the ventricular tissue were assayed by xanthin oxidase method, thiobarbituric acid (TBA) method, Griess method and alkaline hydrolysis method, respectively. Angiotensin II (Ang II) content in serum was detected by radioimmunoasssay method.

Results

XJEK therapy potently improved cardiac function, inhibited myocardial hypertrophy, improved cardiac pathology change, decreased the myocardial cross-section area (CSA), collagen volume fraction (CVF) and perivascular circumferential collagen area (PVCA), reduced the content of Hyp in the left ventricular tissue, inhibited the decrease of SOD activity and increase of MDA, Ang II content in serum. Moreover, treatment with XJEK improved endothelial dysfunction (ED) manifested by promoting endothelial-dependent vasodilation of thoracic aortic rings and enhancing the NO activity in serum.

Conclusions

These findings suggest that administration of XJEK possess protective effects against 2K1C induced hypertension and cardiac remodeling in rats, preserve NO activity and endothelial function.

Investigation of effects and mechanisms of total flavonoids of Astragalus and calycosin on human erythroleukemia cells

Flavonoids are found in most parts of plants and have been shown to have multiple biological activities such as anticancer, anti-inflammation, antibacteria, antivirus, and immune-stimulation. Existing data showed that the total flavonoids of Astragalus (TFA) can provide biological system with resistance to injury and can possess antimutagenic, atherosclerotic inhibition, and other biological effects. This study investigated the effects of TFA and calycosin (a compound isolated from TFA), on apoptosis induction, and cell cycle of human erythroleukemia cell line K562 by an array of techniques, including proliferation (MTT), PI staining, Annexin V/PI double staining, and RT-PCR. The experimental data showed that TFA and calycosin could inhibit the proliferation of K562 cells. The 50% inhibiting concentrations of TFA and calycosin were 98.63 μg/mL and 130.32 μg/mL, respectively. However, TFA and calycosin could not induce apoptosis in K562 cells, but could increase the number of the cells in the G₀/G₁ phase. The level of cyclin D1 mRNA in K562 cells decreased after the treatment with TFA and calycosin. This study provides new insights into the functional mechanism of total flavonoids of Astragalus and calycosin on human erythroleukemia cells.