[Effects of octadecadienoic acid on proliferation and apoptosis of glioma cells and its mechanisms].

OBJECTIVE: To study the effects of octadecadienoic acid (ODA) on the proliferation and apoptosis of glioma cells and its mechanisms. METHODS: Cultured human glioma cells (cell density 2×106 cells/L) were divided into solvent control group (DMSO, 30 µl/L), 5-FU group (10 mg/L) and octadecadienic acid groups (0.3, 0.6 and 1.2 mg/L groups). The toxicity of ODA on glioma cells was detected by trypan blue and thiazolium blue (MTT). The expression levels of P53, PI3K, P21, PKB/Akt and Caspase-9 in glioma cells were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: ① Cell count under optical microscope showed that the inhibition rate of cell proliferation in ODA low, medium and high dose groups and 5-FU group was significantly higher than that in the solvent control group (P＜0.01), but there was no statistical significance compared with the 5-FU group (P＞0.05). ② MTT assay showed that the inhibition rate of cell proliferation was increased significantly in ODA low, medium and high dose groups and 5-FU groups (P＜0.01), compared with the solvent control group. Compared with 5-FU group, the inhibition rate of cell proliferation was increased significantly only in ODA high dose group (P＜0.01). ③ The number of G0/G1 phase cells in ODA low, medium and high dose groups and 5-FU group were increased significantly (P＜0.05, P＜0.01), the number of G2/M phase cells were decreased significantly (P＜0.01), and the apoptosis rate was increased significantly (P＜0.01),compared with the solvent control group. Compared with the 5-FU group, the number of cells in G2/M phase was decreased significantly (P＜0.01) and the apoptosis rate was increased significantly (P＜0.01) in ODA high dose group. ④ ELISA test results showed that the protein expression levels of P53, PI3K and PKB/Akt in ODA low , medium and high dose groups and 5-FU group were significantly lower than those in solvent control group (all P＜0.01), but the protein expression levels in ODA high dose group were significantly lower than those in 5-FU group (P＜0.01). The protein expression levels of P21 and caspase-9 in ODA low , medium and high dose groups and 5-FU group were significantly higher than those in solvent control group (P＜0.05, P＜0.01), but the protein expression levels in ODA high dose group were significantly higher than those in 5-Fu group (P＜0.01). CONCLUSION: ODA can significantly inhibit the proliferation and promote apoptosis of glioma cells. The mechanisms are related to up-regulating the levels of P21 and caspase-9 to promote apoptosis, down-regulating the levels of P53, PI3K and PKB/Akt to inhibit the cell division cycle, and reducing the activity of PI3K-Akt signal transduction pathway.

[Effects of substituted functional groups of cations on retention performance of ionic liquid stationary phases in gas chromatography].

Thirteen stationary phases comprising a polyvinyl imidazolium ionic liquid (IL) in which cations containing propyl, butyl, nonyl, ethyl-phenyl, or cyan methyl functional groups are paired with bis(trifluoromethanesulfonyl) imide ([NTf2]-), trifluoromethanesulfonate ([TFO]-), and hexafluorophosphate ([PF6]-) were synthesized and directly coated inside capillary fused silica tubing for use in gas chromatography. The relationship between the structure of the ILs and the McReynolds constant, thermal stability, and retention behavior of the test compound on the prepared fused silica columns was examined and discussed. The influence of the cationic substituents on retention performance of stationary phases was also studied. The variation in the retention index of the test compound with temperature was also investigated. The results indicated that the synthesized ILs have strong polarity, and that their retention performance is closely related to not only the properties of the cationic substituent but also the structure of the substituted groups and the anion. In the temperature range investigated, the variation in the retention index of the tested compounds was the same as that of conventional chromatographic stationary phases.

[Effects of the maca extract on the ultrastructures of mitochondria in the spinal nerve cell and exercise endurance].

OBJECTIVE: To investigate the effects of maca extract on the ultrastructures of mitochondria in the spinal nerve cell and exercise endurance. METHODS: The Wistar rats were randomly divided into 5 groups, including the control group (no swimming), the swimming group (free swimming), and 3 treatment groups treated with the maca extract at the doses of 4.0, 5.3 and 8.0 g/kg body weight. The animals in swimming and treatment groups were then for free swimming in the circulating water flow daily for 15 days. On the 16th day after swimming endurance, the spinal and muscular tissues were collected from all groups. The mitochondrial ultrastructures of the neurons of the spinal cells were observed with the projection electron microscope, and the levels of the glycogen, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and Ca2+ in muscle tissues were determined by the RIA method. RESULTS: When rats were treated with maca extract (at 4.0, 5.3, 8.0 g/kg body weight), the total swimming time and the swimming duration before sinking were increased by 19.83%, 60.28%, 77.55%, and 55.34%, 73.91%, 94.47%, respectively, compared with the simple swimming group(P<0.01), while the sinking times were decreased by 34.35%, 51.18% and 57.96%, compared with those of the swimming group. Also, the levels of SOD, GSH-Px, and muscle glycogen in three treatment groups were enhanced by 5.12%, 22.74%, 52.53%, 44.22%, 77.79%, 98.45%(P<0.01), and 35.08%, 47.83%,81.88% (P<0.01)respectively over the swimming rats without treatment, but the MDA content and the Ca2+ levels were reduced by 20.10%, 31.49% 38.72%, and 6.42%, 17.58%, 26.35%,compared with the simple swimming group(P<0.01). In addition, compared to the swimming group, the mitochondrial densities of volume (VD), surface (SD) and numbers (ND) of spinal nerve cells in rats treated with maca extract (4.0, 5.3, 8.0 g/kg body weight) were reduced by 7.79%, 18.18%, 31.17%, 16.95%, 27.34%, 43.31% and 13.51%, 23.19%, 43.15%, respectively. CONCLUSIONS: Our results demonstrated the protective effects of maca extract on the mitochondria of spinal cell and suggested that maca extract could improve the muscle antioxidant activity by increasing the levels of SOD, GSH-Px, and muscle glycogen.

[Role of catecholamine hormone in heroin addicts].

OBJECTIVE: To investigate the effects of catecholamine hormone on the blood and brain of heroin addicts. METHODS: Rats were divided into three groups and treated with the glucose (control group), the heroin (im) (heroin group), and the combination of the intramuscular injection of reserpine and heroin (reserpine group). Changes in the levels of the dopamine (DA), cAMP, and cGMP were detected by the radioimmunoassay (RIA) method in the blood and brain tissue. RESULTS: No significant withdrawal symptoms were observed in the reserpine group. Compared with the control and heroin groups, the blood cAMP levels were increased by 35.36% and 15.53% in the reserpine group, respectively; the cAMP levels in the midbrain ventral tegmental area (VTA), prefrontal cortex (PFC), and hippocampus (Hipp) were increased by 24.08% & 8.53%, 15.66% & 8.13%, and 21.95% & 8.40%, respectively. While compared to the control and heroin groups, the DA levels of the PFC, Hipp, striatum, and nucleus accumbens (NAc) were significantly reduced in the reserpine group, decreasing by 74.09% & 82.86%, 81.06% & 82.23%, 91.62% & 86.55% and 84.35% & 90.63%, respectively. The concentrations of cGMP of the brain tissues in the reserpine group were lower than those in the control group. In addition, the neural electrophysiological testing showed that the electroencephalogram (EEG), electrocardiogram (ECG), and muscle spindle discharge diagram of rats in both the reserpine and heroin groups were apparently changed. CONCLUSION: Catecholamine hormone plays an important role in heroin addiction.

Effects of a flavonoid extract from Cynomorium songaricum on the swimming endurance of rats.

The present study investigated the effects of a flavonoid extract from Cynomorium songaricum on the swimming endurance of rats by measuring changes of free radical scavenging enzymes, such as CuZn-SOD (copper, zinc-superoxide dismutase) and GSH-px (glutathione peroxidase), and body weights. Significant and dose-dependent antioxidant and anti-fatigue effects of flavonoids (rutin, catechin and isoquercitrin) on swimming rats were observed during 10 days of swimming exercise. After treatment with the flavonoid extract at doses of 0.5, 1.0, and 2.0 g/kg body weight, the CuZn-SOD and GSH-px activities in swimming rats were increased by 1.4%, 3.3%, 4.1% and 112.2%, 208.7%, 261.7%, respectively, while the levels of MDA (malondialdehyde) were decreased by 64.7%, 79.4%, and 86.4% respectively. Furthermore, the average body weight and the total swimming time were increased by 3.1%, 8.8%, 10.6%, and 7.7%, 34.5%, 61.5%, respectively. Our experimental results suggest that flavonoid supplementation could not only reduce free radical formation and scavenge free radicals, but also enhance endurance exercise performance by reducing muscle fatigue.

Cytotoxic activity of an octadecenoic acid extract from Euphorbia kansui (Euphorbiaceae) on human tumour cell strains.

We have investigated the cytotoxic and antitumour activity of an octadecenoic acid extract, mainly containing oleic and linoleic acids, from Euphorbia kansui on human gastric (SGC-7901), hepatocellular carcinoma (BEL-7402), and leukaemia (HL-60) tumour cell strains. Significant and dose-dependent antiproliferation effects were observed on tumour cells from the dose of 3.2 microg mL(-1), which were comparable with or better than those of the common antitumour agent 5-fluorouracil. Results from the clone formation assay and flow cytometry indicated that the mixture of octadecenoic acids resulted in a dose-dependent reduction in the number of tumour cells and significantly inhibited cell proliferation, with induced apoptosis and G(0)/G(1) phase cell cycle arrest. Also, the octadecenoic acids could not only cause cell apoptosis/necrosis but also functionally and structurally damage the tumour cell membrane and cell ultra-structures. These observations encourage further clinical evaluation of the inhibitory effects of octadecenoic acids on various forms of cancer.

Effects of Hydrocotyle sibthorpioides extract on transplanted tumors and immune function in mice.

This paper describes the effects of an ethanolic extract of Hydrocotyle sibthorpioides on transplanted tumors and immunologic function in mice. When the H. sibthorpioides extract was administered orally at a dose of 1.5 or 3.0 g/kg body wt./day for 10 days, the inhibition rates for murine hepatic carcinoma clone (Hep), sarcoma 180 crocker clone (S(180)), and uterine cervical carcinoma clone (U(14)) were significantly enhanced. The antitumor activity of H. sibthorpioides is comparable to that of the common antitumor agent 5-fluorouracil. Also, our results indicate that the H. sibthorpioides extract promoted the thymus and spleen indices, and humoral immunity of mice. These observations demonstrated that H. sibthorpioides exerted a potent inhibitory effect on the growth of tumors, in addition to mediating immunomodulatory effects in mice.

Phylogeny and biogeography of the Petaurista philippensis complex (Rodentia: Sciuridae), inter- and intraspecific relationships inferred from molecular and morphometric analysis.

With modified DNA extraction and purification protocols, the complete cytochrome b gene sequences (1140 bp) were determined from degraded museum specimens. Molecular analysis and morphological examination of cranial characteristics of the giant flying squirrels of Petaurista philippensis complex (P. grandis, P. hainana, and P. yunanensis) and other Petaurista species yielded new insights into long-standing controversies in the Petaurista systematics. Patterns of genetic variations and morphological differences observed in this study indicate that P. hainana, P. albiventer, and P. yunanensis can be recognized as distinct species, and P. grandis and P. petaurista are conspecific populations. Phylogenetic relationships reconstructed by using parsimony, likelihood, and Bayesian methods reveal that, with P. leucogenys as the basal branch, all Petaurista groups formed two distinct clades. Petaurista philippensis, P. hainana, P. yunanensis, and P. albiventer are clustered in the same clade, while P. grandis shows a close relationship to P. petaurista. Deduced divergence times based on Bayesian analysis and the transversional substitution at the third codon suggest that the retreating of glaciers and upheavals or movements of tectonic plates in the Pliocene-Pleistocene were the major factors responsible for the present geographical distributions of Petaurista groups.

Protective effects of polysaccharide from Euphorbia kansui (Euphorbiaceae) on the swimming exercise-induced oxidative stress in mice.

The present study examined the effects of derivatives of galactosides and glucosides in a polysaccharide extract from Euphorbia kansui (Euphorbiaceae) on exercise-induced oxidative stress in mice. Exhaustive swimming exercise significantly increases the degree of lipid peroxidation in terms of malondialdehyde content and reduces the antioxidant activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Our findings revealed that chronic oral treatment with the extract elevates enzymatic activities of SOD and GPx accompanied by a corresponding decrease in malondialdehyde. The antioxidative activities of these compounds against exercise-induced oxidative stress are correlated with various activities such as reducing the production of superoxide and hydroxyl radicals, inhibiting lipid peroxidation, enhancing antioxidative defenses, and increasing the production of SOD and GPx activity and expression in different tissues. These compounds may be involved in glycogen metabolism to meet the requirement of working skeletal muscles and act as antioxidants by terminating the chain reaction of lipid peroxidation to maintain the morphological stability of mitochondria in spinal motor neurons. These observations suggest that E. kansui has antioxidative and antifatigue properties and can be given as prophylactic and (or) therapeutic supplements for increasing antioxidant enzyme activities and preventing lipid peroxidation during strenuous exercise.

Isolation and characterization of methyl esters and derivatives from Euphorbia kansui (Euphorbiaceae) and their inhibitory effects on the human SGC-7901 cells.

PURPOSE: In this study, the inhibitory activity of the methyl esters and derivatives extracted from Euphorbia kansui (Euphorbiaceae) and their effect on apoptosis and cell cycle distribution in the human gastric cancer cell line (SGC-7901) were evaluated. METHODS: The inhibitory activity of the methyl esters and derivatives was evaluated by using trypan-blue, MTT (3-(4, 5-dimethyl thiazol-2yl) - 2, 5-diphenyltetrazolium bromide), and FCM (flow cytometry) assays. 5-fluorouracile (5-FU) was used for a positive control. RESULTS: Six new methyl esters and derivatives were extracted from the root of E. kansui. Subjecting the SGC-7901 cell line to the extract indicated that methyl ester derivatives could initiate growth inhibition and induce apoptosis in these tumor cells. The inhibitory rates as measured from trypan-blue and MTT assays were significantly increased and are comparable to those of the common antitumor agent 5-FU. In addition, the methyl ester extract effectively inhibited the proliferation of SGC-7901 cells by interfering with the progression of the cells through the G1 phase of the cell cycle. CONCLUSION: The current study indicates that methyl esters might be a promising chemopreventive and chemotherapeutic agent for treating various forms of cancer by causing apoptosis and proliferation inhibition.

Molecular phylogeny and biogeography of woolly flying squirrel (Rodentia: Sciuridae), inferred from mitochondrial cytochrome b gene sequences.

To investigate the genetic diversity between the populations of woolly flying squirrels (Eupetaurus) from the eastern and western extremes of the Himalayas, partial mitochondrial cytochrome b gene sequences (390-810 bp) that were determined from the museum specimens were analyzed using maximum parsimony (MP) and maximum likelihood (ML) methods. The molecular data reveal that the two specimens that were collected in northwestern Yunnan (China) are members of the genus Eupetaurus. Reconstructed phylogenetic relationships show that the populations of Eupetaurus in the eastern and western extremes of the Himalayas are two distinct species with significant genetic differences (12%) and diverged about 10.8 million years ago. Eupetaurus is significantly different from Petaurista and Pteromys. The level of estimated pairwise-sequence divergence observed between Eupetaurus and Petaurista or Pteromys is greater than that observed between Eupetaurus and Trogopterus, Belomys, Glaucomys, or Hylopetes. Considering the divergence time of the two Eupetaurus groups, the glaciations and the uplift of the Himalayas and Qinghai-Tibet plateau during the Pliocene-Pleistocene period might be the major factors affecting the present distribution of Eupetaurus along the Himalayas.

Inhibitory effects of the Gentiana macrophylla (Gentianaceae) extract on rheumatoid arthritis of rats.

Acute treatment of rheumatoid rats with an extract from the roots of Gentiana macrophylla (Gentianaceae) produced a significant inhibitory effect on rheumatoid arthritis (RA). When rats were administered the Gentiana macrophylla extract orally at a daily dose of 100 mg/kg body weight, the prostaglandin E(2) (PGE(2)) levels in the inflammatory tissues, sole thickness, and ankle circumferences of feet were significantly decreased. The anti-inflammatory activity observed in Gentiana macrophylla is comparable to that observed in prednisone. These observations suggest that Gentiana macrophylla displays considerable potency in anti-inflammatory action and could be used as an anti-inflammatory agent in the control of inflammation of rheumatoid arthritis.

Toxic effect of chloromycetin on the ultrastructures of the motor neurons of the Chinese tree shrew (Tupaia belangeri).

This paper describes the toxic effects of chloromycetin on the motor neurons of the Chinese tree shrew (Tupaia belangeri chinensis) with horse radish peroxidase (HRP) as the labeling enzyme. When chloromycetin was administered orally at 2.5 mg/kg (body weight)/day for 3 days, Chinese tree shrews showed evidence of neurotoxicity. This included damage in cortical motor neuron synapses ending on neurons of the red nucleus and the ultrastructural changes in the mitochondria such as swelling of these organelles and blurring of their cristae. There was an increase of the mitochondrial matrix density and of the thickness of the synaptic membranes. These observations indicate that chloromycetin can lead to ultrastructural change of terminals of the cortical motor axons, and that Chinese tree shrews are sensitive animal model for chloromycetin neurotoxicity.