Xing Zeng

Application of a liquid chromatography/tandem mass spectrometry method to pharmacokinetic study of mangiferin in rats

A simple, rapid and accurate liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed and validated for quantification of mangiferin in rat plasma. After the addition of the internal standard (IS) paracetamol, plasma samples were pretreated by protein precipitation. Chromatographic separation was carried out on a C(18) column by isocratic elution with methanol-acetonitrile-1% acetic acid (40:3:57, v/v/v). The detection was performed on a Sciex API 3000 LC/MS/MS with TurboIonSpray ionization (ESI) inlet in the positive ion MRM mode. Good linearity was achieved over the concentration range of 3.01-601 ng/mL. Intra- and inter-day precisions were less than 9.1%, and accuracy ranged from 100.5% to 104.0%. The pharmacokinetic profiles of free mangiferin at three dose levels and mangiferin in Zhimu decoction and Zhimu-Huangbai decoction were studied for the first time in rats by this method. After single intragastric administration of free mangiferin 17.5, 35 and 70 mg/kg, C(max) and AUC increased but non-proportional to the doses. At the same dose level (35 mg/kg), C(max) and AUC of mangiferin in two decoctions were significantly higher than the corresponding values of free mangiferin.

Pharmacokinetics and Safety of Ginsenoside Rd Following a Single or Multiple Intravenous Dose in Healthy Chinese Volunteers

The pharmacokinetics and safety of ginsenoside Rd (Rd) were assessed in healthy Chinese volunteers. In the single‐dose study, a randomized, open‐label, 3‐way crossover design was used. Participants were assigned to receive 10, 45, or 75 mg Rd by intravenous infusion, with a 2‐week washout period between dosing periods. Plasma levels of Rd were found to be proportional to dose, with the mean Cmax and AUC0‐∞ ranging from 2.8 to 19.3 mg/L and 27.9 to 212.5 mg·h/L over the dose range studied. Ginsenoside Rd was slowly cleared from plasma (t1/2Z = 17.7–19.3 hours). In the multiple‐dose study, 10 mg Rd was administered once daily for 6 days. Slight drug accumulation was noted. The mean steady‐state Cmax, AUC0‐∞, and AUCss were 4.0 mg/L, 51.7 mg·h/L, and 26.4 mg·h/L, respectively. The t1/2Z was 20.5 hours, which was similar to the single‐dose value. Ginsenoside Rd was well tolerated with no pattern of dose‐related adverse events. It had a favorable pharmacokinetic and safety profile that enables the drug to be explored in future clinical studies that target patients with acute ischemic stroke.

Determination of ginsenoside‐Rg1 in human plasma and its application to pharmacokinetic studies following intravenous administration of ‘Shenmai’ injection

‘Shenmai’ injection is derived from traditional Chinese medicine ‘Shenmaisan’ and made from Radix ginseng Rubra and Radix Ophiopogonis. Ginsenoside‐Rg1, as a major constituent of Radix ginseng Rubra, is considered responsible for the efficacy of this injection. A rapid, simple and accurate method has been established for determination of ginsenoside‐Rg1 in Shenmai injection and human plasma using LC‐ESI‐MS/MS, and to study the pharmacokinetics of Rg1 in ten healthy volunteers after intravenous single dosing of 60 mL of Shenmai injection. Following solid‐phase extraction (SPE), samples were separated on a C18 column coupled with electrospray ionization mass spectrometry. The protonated analyte was quantified by multiple reaction monitoring (MRM) with a quadruple mass spectrometer in positive mode. Linearity was confirmed in the concentration range of 1 to 1000 ng/mL for Rg1, and the lower limit of quantification (LLOQ, S/N > 10) was 1 ng/mL. The intraday and interday RSDs were within 15% and mean extraction recoveries ranged from 98.6% to 104.9%. The pharmacokinetics of Rg1 in healthy volunteers conforms to the two‐compartment open model. The main pharmacokinetics parameters were as follows: t1/2β, 2.09 ± 1.89 h; CL, 0.03 ± 0.01 L kg−1 h−1; AUC (0 ∼ ∞), 124.4 ± 35.9 2 ng mL−1 h and AUC (0 ∼ ∞), 127.9 ± 37.2 ng mL−1 h, respectively. Copyright

Anti-Inflammatory Effects of p-coumaric Acid in LPS-StimulatedRAW264.7 Cells: Involvement of NF-úB and MAPKs Pathways

P-coumaric acid (p-CA), which was widely found in nutritious plant foods, has various anti-inflammatory effects in vivo. In order to clarify the anti-inflammatory mechanisms, the effects on lipopolysaccharide (LPS)-stimulated inflammatory responses in RAW264.7 macrophage cells were examined by pretreated with P-CA (10-100 μg/ml). P-CA signii¬x81cantly inhibited iNOS, COX-2, IL-1β and TNF-α expression at mRNA and/or protein level. Furthermore, P-CA suppressed the phosphorylation of IκB and ERK1/2. The above results suggest that P-CA may inhibit the production of inflammatory cytokines induced by LPS through blocking NF-kB and MAPKs signaling pathways, which further support the anti-inflammatory and immunomodulatory potential of P-CA in different models of inflammation.

Innate and adaptive immune responses in patients with pandemic influenza A(H1N1)pdm09

Innate and adaptive immune responses play critical roles in the body’s defense against viruses. We investigated the host immune response against the 2009 pandemic H1N1 influenza virus [A(H1N1)pdm09] in patients before and after anti-influenza therapy and found that the numbers of dendritic cells and T cells were significantly reduced compared with those of a healthy control group. In contrast, the frequency of natural killer, γδT and T regulatory (Treg) cells increased, and the concentrations of plasma interferon (IFN)-α/γ and interleukin (IL-15) were significantly higher than those of the control. Following therapy the frequency of γδT and Treg cells returned to normal; the counts of myeloid dendritic and plasmacytoid dendritic cells were still lower than the control, while the concentrations of IFN-α/γ and IL-15 remained high. We show that infection with A (H1N1)pdm09 was accompanied by changes in peripheral blood lymphocyte subgroups and cytokine profiles, leading to deleterious imbalances in innate and adaptive immunity.

NF-κB pathways are involved in M1 polarization of RAW 264.7 macrophage by polyporus polysaccharide in the tumor microenvironment

Bladder cancer is one of the most malignant tumors closely associated with macrophages. Polyporus polysaccharide (PPS) has shown excellent efficacy in treating bladder cancer with minimal side effects. However, the molecular mechanisms underlying the effects of PPS in inhibiting bladder cancer remain unclear. In this study, we used macrophages cultured alone or with T24 human bladder cancer cell culture supernatant as study models. We found that PPS enhanced the activities of IFN-γ-stimulated RAW 264.7 macrophages, as shown by the release of inducible nitric oxide synthase (INOS), secretion of tumor necrosis factor (TNF)-α and interleukin (IL)-6, phagocytosis activity, as well as expression of M1 phenotype indicators, such as CD40, CD284 and CD86. PPS acted upstream in activation cascade of nuclear factor (NF)-κB signaling pathways by interfering with IκB phosphorylation. In addition, PPS regulated NF-κB (P65) signaling by interfering with Toll-like receptor (TLR)-4, INOS and cyclooxygenase (COX)-2. Our results indicate that PPS activates macrophages through TLR4/NF-κB signaling pathways.

Systematic Analysis of Absorbed Anti-Inflammatory Constituents and Metabolites of Sarcandra glabra in Rat Plasma Using Ultra-High-Pressure Liquid Chromatography Coupled with Linear Trap Quadrupole Orbitrap Mass Spectrometry.

Ultra-high-pressure liquid chromatography (UHPLC) was coupled with linear ion trap quadrupole Orbitrap mass spectrometry (LTQ-Orbitrap) and was used for the first time to systematically analyze the absorbed components and metabolites in rat plasma after oral administration of the water extract of Sarcandra glabra. This extract is a well-known Chinese herbal medicine for the treatment of inflammation and immunity related diseases. The anti-inflammatory activities of the absorbed components were evaluated by measuring nitric oxide (NO) production and proinflammatory genes expression in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages. As a result, 54 components in Sarcandra glabra were detected in dosed rat plasma, and 36 of them were positively identified. Moreover, 23 metabolites were characterized and their originations were traced. Furthermore, 20 of the 24 studied components showed anti-inflammatory activities. These results provide evidence that this method efficiency detected constituents in plasma based on the anti-inflammatory mechanism of multiple components and would be a useful technique for screening multiple targets for natural medicine research.

Simultaneous quantification of 17 bioactive constituents in Sarcandra glabra by liquid chromatography-electrospray ionisation-mass spectrometry

A high performance liquid chromatography with electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) method has been developed to quantify 17 bioactive compounds in Sarcandra glabra and its preparation simultaneously. These constituents including flavones, coumarins, caffeoyl derivatives and sesquiterpenoids were detected in the negative ion mode ESI-MS and quantified by multiple reaction monitoring (MRM). All 17 constituents were separated and determined within 17 minutes. The linear regressions were acquired with r2 > 0.9990, respectively. The precision was evaluated by intra- and inter-day tests, and relative standard deviation (R.S.D.) values were reported within the range of 0.86–2.29%, 1.16–4.83% and 0.87–4.94%, 0.69–4.92% for mixed standard solutions and extract solutions, respectively. The recovery studies for the assayed constituents were observed over the range of 80.20–119.68%. It is demonstrated that the method developed was successfully applied for quantification of 17 main constituents, which provided a new basis for overall assessment on the quality of S. glabra and its preparation.

A new coumarin isolated from Sarcandra glabra as potential anti-inflammatory agent.

Abstract One new coumarin, 3,5-dihydroxy-7-O-α-L-rhamno pyranosyl-2H-chromen-2-one (1), was isolated from the whole plant of Sarcandra glabra. The structure was elucidated by spectroscopic methods. Our results indicated that 1 significantly inhibit nitric oxide (NO) production in LPS-induced RAW264.7 macrophages. RT-PCR analysis indicated it inhibited iNOS mRNA expression. In addition, Western blot analysis showed that 1 attenuated LPS-induced synthesis of iNOS protein in the macrophages. These results suggest that 1 could be potential anti-inflammatory agent by down-regulating iNOS expression. Graphical abstract

Licochalcone B, a chalcone derivative from Glycyrrhiza inflata, as a multifunctional agent for the treatment of Alzheimer’s disease

Abstract Licochalcone B (LCB), an extract from the root of Glycyrrhiza inflate, has the same caffeic acid scaffold as curcumin (Cur), which is known as an anti-Alzheimer’s disease (AD) agent. However, there is no relevant research about anti-AD activity of LCB. In this study, the anti-AD activity of LCB was investigated. LCB could inhibit amyloid beta (Aβ42) self-aggregation (IC50u2009=u20092.16u2009±u20090.24u2009μM) and disaggregate pre-formed Aβ42 fibrils, reduce metal-induced Aβ42 aggregation through chelating metal ions. Molecular docking further revealed that LCB inhibited Aβ42 self-aggregation through forming two hydrogen bonds with Lys28 to block the salt bridge interaction at the C-terminus of Aβ42. Anti-oxidant property of LCB was also observed by DCFH-DA assay. In addition, LCB did show neuroprotective activity against H2O2-induced cell death in SH-SY5Y cells. In general, our results demonstrate that LCB, as a multifunctional agent, is likely to be promising therapeutics for AD.