Li-Hua Mu

Acute and subchronic oral toxicity assessment of the herbal formula Kai-Xin-San

ETHNOPHARMACOLOGICAL RELEVANCE Kai-Xin-San (KXS) is a famous traditional Chinese medicine (TCM) formula. It has been used in the treatment of diseases including neurasthenia, Alzheimers disease and neurosis. AIM OF THE STUDY To provide information on the potential toxicity of KXS, we evaluated the acute and subchronic toxicity in rodents. MATERIALS AND METHODS In acute study, a single administration of KXS was given orally to mice at doses ranging from 19.67 to 60.04 g/kg. In the sub-chronic oral toxicity study, KXS was administered to rats at 0, 1, 3 and 9 g/kg for 13 weeks. Moreover, 30 days of post treatment (withdrawal study) was conducted. Mortalities, clinical signs, body weight changes, food and water consumption, haematological and biochemical parameters, gross findings and organ weights were monitored during the study period. RESULTS In the sub-chronic study in rats, daily oral administration of KXS at the dose of 9 g/kg/day result in significant increase in WBC, lymphocyte, alkaline phosphatase, blood sugar and significant decrease in bodyweight, serum Cre, CK and CHO at the last week of treatment. Recovery except for the body weight was observed after 30 days of post treatment. CONCLUSIONS KXS is relatively safe for oral medication. The LD(50) of KXS was over 32.59 g/kg for mice. The no-observed-adverse-effect-level (NOAEL) was considered to be 19.67 g/kg/day for rats.

Effect of Tenuifoliside A isolated from Polygala tenuifolia on the ERK and PI3K pathways in C6 glioma cells

Tenuifoliside A (TFSA) is a bioactive oligosaccharide ester component of Polygala tenuifolia Wild, a traditional Chinese medicine which was used to manage mental disorders effectively. The neuroprotective and anti-apoptotic effects of TFSA have been demonstrated in our previous studies. The present work was designed to study the molecular mechanism of TFSA on promoting the viability of rat glioma cells C6. We exposed C6 cells to TFSA (or combined with ERK, PI3K and TrkB inhibitors) to examine the effects of TFSA on the cell viability and the expression and phosphorylation of key proteins in the ERK and PI3K signaling pathway. TFSA increased levels of phospho-ERK and phospho-Akt, enhanced release of BDNF, which were blocked by ERK and PI3K inhibitors, respectively (U0126 and LY294002). Moreover, the TFSA caused the enhanced phosphorylation of cyclic AMP response element binding protein (CREB) at Ser133 site, the effect was revoked by U0126, LY294002 and K252a. Furthermore, when C6 cells were pretreated with K252a, a TrkB antagonist, known to significantly inhibit the activity of brain-derived neurotrophic factor (BDNF), blocked the levels of phospho-ERK, phospho-Akt and phosphor-CREB. Taking these results together, we suggested the neuroprotection of TFSA might be mediated through BDNF/TrkB-ERK/PI3K-CREB signaling pathway in C6 glioma cells.

Synthesis and inhibitory effect of piperine derivates on monoamine oxidase.

A series of piperine derivates (1-19) have been designed, synthesized and evaluated in vitro for their monoamine oxidase (MAO) A and B inhibitory activity and selectivity. It is worth noting that most of the small amine moieties substituted on the piperidine ring proved to be potent and selective inhibitors of MAO-B rather than of MAO-A. 5-(3,4-methylenedioxyphenyl)-2E,4E-pentadienoic acid n-propyl amide (3) showed the greatest MAO-B inhibitory activity (IC(50)(MAO-B)=0.045 μM) and good selectivity (IC(50)(MAO-A)=3.66 μM). The conjugated double bond and carbonyl group of piperine are proved to be an essential feature for piperine and related alkylamides to exhibit MAO-inhibitory activity. Binding mode of the titled compounds was predicted using FlexX algorithm. The design and optimization of novel small molecule monoamine oxidase inhibitors will be guided by the results of this report.

Antioxidant activity of oligosaccharide ester extracted from Polygala tenuifolia roots in senescence-accelerated mice

The constituents of the ethanol extract from the root of Polygala tenuifolia Willd. (Polygalaceae) were investigated for antioxidant activity in senescence-accelerated mice. Consequently, two relevant samples were obtained, a fraction separated by macroporous resin (YZ-OE), and a major pure crystal of 3,6′-disinapoyl sucrose (DISS). Based on HPLC-ESI-MS analysis, the most constituents in the YZ-OE fraction from the extract of P. tenuifolia were oligosaccharide esters. The antioxidant activities of these two samples were evaluated using the accelerated senescence-prone, short-lived mice (SAMP) in vivo. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) were increased significantly in SAMP mice fed oligosaccharide esters (YZ-OE 50 mg/kg) and its constituents (DISS 50 mg/kg). However, the content of malondialdehyde (MDA) was increased in the blood and liver of SAMP mice. But when given YZ-OE, it could be decreased, by 44.3% and 47.5%, respectively, compared with the SAMP model. Results from the analyses indicated that the oligosaccharide esters (YZ-OE) from roots of P. tenuifolia had a high in vivo antioxidant activity.

A representative prescription for emotional disease, Ding-Zhi-Xiao-Wan restores 5-HT system deficit through interfering the synthesis and transshipment in chronic mild stress-induced depressive rats.

ETHNOPHARMACOLOGICAL RELEVANCE Ding-Zhi-Xiao-Wan (DZ, also known as Kai-Xin-San) is a famous traditional Chinese medicine used for the treatment of emotional disease. Previously, we have found that in a variety of animal models of depression (such as tail suspension model, model of chronic fatigue and forced swimming model) DZ demonstrated significant antidepressant behavior and promoted the production of 5-hydroxytryptamine (5-HT). However, the mechanisms of 5-HT regulation are still unclear. Therefore, the current study is designed to further investigate the antidepressant effect of DZ by observing its influence on 5-HT synthesis, metabolism, transport and other key links, so as to clarify the molecular mechanism of its 5-HT regulation. MATERIALS AND METHODS Solitary rising combined with the chronic unpredictable mild stress (CMS) was used to establish the rat model of depression. The rats were given DZ for 3 weeks, the behavior change and the following items in hippocampus and prefrontal cortex were detected simultaneously: 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), tryptophan hydroxylase (TPH), aromatic amino acid decarboxylase (AADC), monoamine oxidase (MAO) and 5-HT transporter (5-HTT) were observed. RESULTS Our results showed that treatment with the DZ significantly improved the behavior and simultaneously increased the 5-HT level in the hippocampus, prefrontal cortex tissues and hippocampus extracellular of depressive rats. In future studies revealed that DZ could significantly increase the protein and mRNA expression of the key enzymes TPH during the 5-HT synthesis process in the hippocampus and prefrontal cortex of the depressed rats, and suppress the expression of 5-HTT protein and mRNA at the same time. But it had no effects on MAO-A and MAO-B activities. CONCLUSION We believe that antidepressant effect of DZ is caused by the increase of 5-HT synthesis and reduction of 5-HT re-uptake, and eventually increase the content of 5-HT in the brain and the synaptic gaps.

Methanolysis of triterpenoid saponin from Ardisia gigantifolia stapf. and structure–activity relationship study against cancer cells

Thirteen 13,28-epoxy triterpenoid saponins were isolated from Ardisia gigantifolia stapf. and one potential anti-tumor saponin was methanolysised by H2SO4 to afford four new compounds. The seventeen compounds were evaluated for their anti-proliferative activity on A549, HCT-8 and Bel-7402 cells. The structure-activity relationship analysis indicated that the incorporation of =O group at C-16, L-rhamnose at R(5) and acetyl group at OH-6 of the D-glucose lead to a significant increase of the cytotoxic activity on A549 and HCT-8 but significant reduction of the cytotoxic activity on Bel-7402 cells. The synthesized saponins losing 13,28-epoxy and CHO at C-30, losed their cytotoxicities on A549 and HCT-8 cells, suggesting that the two moieties play an essential role for activity. 3β-O-α-L-rhamnopyranosyl-(1→3)-[β-D-xylopyranosyl-(1→2)]-β-D-glucopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→2)]-α-l-arabinopyranoside-16α-hydroxy-13,28-epoxy-oleanane (2) showed better inhibitory activity to Bel-7402 (IC50 0.86 μM) than that of 5-FU (IC50 8.30 μM), which indicate that five saccharide and methyl moiety at C-30 are important for anti-proliferative activity. The activities of saponins 15>14, 17>16, suggested that the configuration of 28,30-epoxy is preferable to be 30(R) rather than 30(S) on Bel-7402 cells. Further molecular mechanism studies of saponins 1 and 2 were carried out on the cell cycle distribution of Bel-7402 cells.

A new triterpenoid saponin from Ardisia gigantifolia

A new triterpenoid saponin, named 3-O-β-d-glucopyranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 4)-[β-d-glucopyranosyl-(1 → 2)]-α-l-arabinopyranosyl-3β,16α,28,30-tetrahydroxy-olean-12-ene (1), along with four known triterpenoids (2–5), was isolated from the rhizomes of Ardisia gigantifolia. Their structures were elucidated by spectroscopic methods. Compounds 1–4 showed cytotoxic activity against Hela, EJ, BCG, and HepG-2 cell lines. The percentage of early apoptotic cells after treatment with 1 was significantly increased compared with control cells (p < 0.05).

One new cycloartane triterpene glycoside from Beesia calthaefolia

One new cycloartane triterpene glycoside (1) was isolated from the whole plant of Beesia calthaefolia. Its structure was elucidated on the basis of extensive spectroscopic data analysis. Its inhibitory effect was measured by the classical pathway of the complement system, and compared with those of known related cycloartane glycosides 2 and 3, previously isolated by us from the same plant. Compounds 1 and 2 exhibited inhibitory activity of complement system with IC50 of 395.3 and 214 μM, respectively. The results suggested that OH at C-12, C-18 and C-15 along with the polarity could affect the inhibitory activity.

UPLC-Q-TOF-MS(E) analysis of the constituents of Ding-Zhi-Xiao-Wan, a traditional Chinese antidepressant, in normal and depressive rats.

Ding-Zhi-Xiao-Wan (DZXW) is a traditional Chinese medicine widely used for treating depression. To clarify the bioactive constituents of DZXW, a new rapid ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS(E)) method was established in this study, with the whole extract of the formula separated into multiple components to facilitate the analytical process. In total, 97 compounds were detected and 88 were identified in DZXW. Based on their exact masses, fragmentation characteristics, and retention times, 85 of the 88 compounds were confirmed either conclusively or tentatively, and three potentially novel compounds were identified. In addition, following a three-day oral administration of DZXW, 60 and 28 compounds were observed in the plasma of normal and depressive rats, respectively. Finally, by combining our data with pharmacological information, 10 compounds were predicted as the likely bioactive constituents of DZXW as an antidepressant agent. Our approach provided a rapid method for characterising the chemical constituents of DZXW, and we were the first to screen for bioactive indexes in the plasma of depressive rats. Furthermore, our results provide useful chemical information that could be employed for further study of the pharmacodynamic material basis of DZXWs antidepressant effects.

Effect of linezolid on hematological and oxidative parameters in rats.

Effect of linezolid is associated with hematocytopenia. A possible relationship between oxidative stress and hematologic toxicity has also been discussed. This present study was performed to determine the effect of oral administration of linezolid on hematological and oxidative parameters in rats. Rats were divided into five groups of 20 each. Drugs were given for a 15-day period. Control rats were vehicle treated. In the second and third groups, linezolid (50 and 125 mg kg−1) was given to rats twice a day (100 and 250 mg kg−1 per day) orally by gavage. The fourth group was given diet supplement that contained 250 mg kg−1 Vitamin E. The fifth group was given 125 mg kg−1 linezolid twice a day along with Vitamin E supplement. Blood cell counts (red blood cell (RBC), white blood cell (WBC) and platelet) were measured every 5 days. Enzymatic antioxidant activities, lipid peroxidation and free radical production were performed at the end of 15th day. The results showed that linezolid induces a decrease of WBC, RBC and platelet numbers in rat blood and enzymatic activities of superoxide dismutase and catalase in rat serum in a dose-dependent manner. While the content of malondialdehyde and nitric oxide was significantly increased in rats serum compared with the control group, Vitamin E supplement could partially reverse the above changes without affecting the control group. The results suggest that linezolid has effect on decreasing hemocyte level in rats, and oxidative stress may be one of the major causative factors. Antioxidant may prove to be a useful therapeutic option in the reversal of hematologic effects induced by linezolid.