Analysis of Acanthopanax giraldii Harms Polysaccharide II Composition and Its Immune-Protective Role in a Cyclophosphamide-Induced Immunosuppressive Mice Model.

Acanthopanax giraldii Harms is commonly used in traditional Chinese medicine to treat rheumatism, improve joints, and strengthen muscles and bones. The polysaccharides present in A. giraldii Harms contain major bioactive substances, which have antioxidant, anticancer, and antiviral activities. In this study, the structural characterization of the homogeneous polysaccharide isolated from A. giraldii Harms, known as AHP-II, and its immunomodulatory effects in vivo will be studied. High-performance ion chromatography (HPIC) and high-performance gel permeation chromatography (HPGPC) based analyses revealed that AHP-II was composed of various monosaccharides, which included rhamnose, arabinose, galactose, glucose, mannose, galacturonic acid, and glucuronic acid in molar ratios of 29.5 : 24.6 : 23.8 : 4.4 : 5.7 : 8.8 : 3.1, respectively, and had a collective molecular weight of 80.21 × 103 Da. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of a pyranose ring and ß-type glycosidic linkages in AHP-II. In addition, immunomodulatory effect analyses of AHP-II that used a cyclophosphamide-induced immunosuppressive mouse model demonstrated that its treatment could significantly restore spleen and thymus indices, promote the proliferation of splenic lymphocytes, elevate CD4+ T lymphocyte percentage and CD4+ : CD8+ ratio in the spleen, promote macrophage phagocytosis, and restore cytokines (IL-6, TNF-α, IgM, and IgG) levels. These results suggested that AHP-II could potentially be used as natural immunomodulator and as an alternative treatment to reduce chemotherapy-induced immunosuppression.

Binding of the polysaccharide from Acanthopanax giraldii Harms to toll-like receptor 4 activates macrophages.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional Chinese medicine, Acanthopanax giraldii Harms, is commonly used to treat arthralgia due to wind, cold and dampness, as well as weakness in the feet and knees. Its other reported effects include eliminating flatulence, strengthening muscles and bones, and delaying aging. The polysaccharides in A. giraldii Harms are the major bioactive substances that confer the herb's antioxidant properties as well as anticancer and antiviral effects. AIMS OF THE STUDY: To elucidate the underlying mechanism and signaling cascade involved in the homogeneous A. giraldii Harms polysaccharide II (AHP-II)-mediated immunomodulation of mice macrophages. MATERIALS AND METHODS: The phagocytosis of neutral red and the production of nitric oxide, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), were measured to determine AHP-II-induced macrophage activation. Confocal microscopy and flow cytometry were used to confirm the binding of AHP-II to macrophages. The involvement of Toll-like receptor (TLR) 4 in AHP-II-induced macrophage activation was demonstrated using antibody blocking and macrophages from C3H/HeJ TLR4-mutant mice. Western blotting was used to map AHP-II-induced downstream signaling pathways. RESULTS: AHP-II increased the phagocytosis of macrophages and the release of nitric oxide, IL-6 and TNF-α cytokines. Direct, saturable and reversible binding of AHP-II to macrophages was observed, while it can be inhibited by the anti-TLR4 antibody. In addition, the presence of the anti-TLR4 antibody inhibited AHP-II-induced macrophage IL-6 and TNF-α production in the peritoneal macrophages of C3H/HeJ mice. Moreover, AHP-II-TLR4-stimulated macrophages activate the downstream intracellular ERK and JNK/nuclear factor (NF)-κB signaling pathways. In addition, the AHP-II-mediated regulation of IL-6 and TNF-α production from macrophages was greatly affected by specific ERK, JNK and NF-κB inhibitors. CONCLUSION: Our study elucidated the immunomodulatory mechanism of AHP-II in macrophage activation and identified TLR4 as the main receptor coordinating AHP-II binding. Our findings suggest AHP-II may be used as a novel immunopotentiator for medical purposes.

Effect Of epigallocatechin-3-gallate on the pharmacokinetics of amlodipine in rats.

This study investigates the effect of epigallocatechin-3-gallate (EGCG), a major ingredient of green tea, on the pharmacokinetics of amlodipine in rats. The pharmacokinetics of orally administered amlodipine (1 mg/kg) with or without EGCG pretreatment (30 mg/kg/day for 10 days) were investigated. Plasma concentrations of amlodipine were determined by using a sensitive and reliable liquid chromatography with tandem mass spectroscopy (LC-MS/MS) method. The effects of EGCG on the metabolic stability of amlodipine were investigated by using rat liver microsome incubation systems. The results indicated that when the rats were pretreated with EGCG, the Cmax of amlodipine increased from 16.32 ± 2.57 to 21.44 ± 3.56 ng/mL (p < 0.05), the Tmax decreased from 5.98 ± 1.25 to 4.01 ± 1.02 h (p < 0.05), and the AUC0-t increased from 258.12 ± 76.25 to 383.34 ± 86.95 µg h L-1 (p < 0.05), which suggested that the pharmacokinetic behavior of amlodipine was affected after oral co-administration of EGCG. Additionally, the metabolic half-life was prolonged from 31.3 ± 5.6 to 52.6 ± 7.9 min (p < 0.05) with the pretreatment of EGCG. It can be speculated that the drug-drug interaction between EGCG and amlodipine might occur, which might have resulted from the metabolism inhibition of amlodipine by EGCG when they were co-administered.

In vitro suppression of quercetin on hypertrophy and extracellular matrix accumulation in rat glomerular mesangial cells cultured by high glucose.

Quercetin's protective effects on the glomerulosclerosis of diabetic nephropathy (DN) in rat mesangial cells were investigated. The cell cycles, type IV collagen and laminin, TGF-ß(1) mRNA, Smad 2/3 and Smad 7, and activities of cell antioxidases were measured. Compared with the high glucose group, quercetin may decrease the cell percentages of G(0)/G(1) phase, Smad 2/3 expression, laminin and type IV collagen, and TGF-ß(1) mRNA level significantly. The antioxidant capacity, the cell percentages of S phase and Smad 7 expression was significantly increased by quercetin. These results suggest that quercetin is a protective agent against glomerulosclerosis in DN.