The Effects of Astragalus Polysaccharide on Bone Marrow-Derived Mesenchymal Stem Cell Proliferation and Morphology Induced by A549 Lung Cancer Cells.

BACKGROUND The tumor microenvironment in lung cancer plays an important role in tumor progression and metastasis. Bone marrow-derived mesenchymal stem cells (MSCs) co-cultured with A549 lung cancer cells show changes in morphology, increase cell proliferation, and cell migration. This study aimed to investigate the effects of Astragalus polysaccharide (APS), a traditional Chinese herbal medicine, on the changes induced in bone marrow-derived MSCs by A549 lung cancer cells in vitro. MATERIAL AND METHODS Bone marrow-derived MSCs were co-cultured with A549 cells (Co-BMSCs). Co-cultured bone marrow-derived MSCs and A549 cells treated with 50 µg/ml of APS (Co-BMSCs + APS) were compared with untreated Co-BMSCs. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay. Flow cytometry evaluated the cell cycle. Microarray assays for mRNA expression and Western blot for protein expression were used. RESULTS Compared with untreated Co-BMSCs, APS treatment of Co-BMSCs improved cell morphology, reduced cell proliferation, and inhibited cell cycle arrest. The mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-kappaB) pathway, TP53, caspase-3, acetylated H4K5, acetylated H4K8, and acetylated H3K9 were involved in the regulatory process. CONCLUSIONS APS treatment reduced cell proliferation and morphological changes in bone marrow-derived MSCs that were co-cultured with A549 lung cancer cells in vitro.

[Effect of ultrafiltration-membrane extracts of Radix Rehmanniae Praeparata on proliferation and genetic stability of bone marrow-derived mesenchymal stem cells induced by cadmium chloride].

OBJECTIVE: To study the effect of ultrafiltration-membrane extracts of Radix Rehmanniae Praeparata (UMERRP) on theproliferation and genetic stability of bone marrow-derived mesenchymal stem cells (BMSCs) induced by cadmium chloride (CdCl2). METHODS: Protective effects on the proliferation, micronuclear rates, chromosome aberration rates, and apoptosis rates were observed by micronuclei test, karyotype analysis, and flow cytometry. RESULTS: Compared with the CdCl2 group, UMERRP with different molecular weights at 0. 8 g/L could obviously promote the proliferation (P <0. 05). Compared with the control group, micronuclear rates, chromosome aberration rates, and apoptosis rates were obviously enhanced in the CdCl2 group (P <0. 05). Compared with the CdCl2 group, UMERRP with different molecular weights could obviously decreased CdCl2 induced micronuclear rates, chromosome aberration rates, and apoptosis rates (P <0. 05). Of them, BMSC micronuclear rates and chromosome aberration rates decreased most obvious in UMERRP groups with molecular weight below 10 000 (P <0. 05). The apoptosis rate decreased most obviously in UMERRP groups with molecular weight ranging 100 000 and 200 000 (P <0. 05). CONCLUSION: UMERRP could reduce CdCl2 induced micronuclear rates, chromosome aberration rates, and apoptosis rates.

The influence of the total flavonoids of Hedysarum polybotry on the proliferation, cell cycle, and expressions of p21Ras and proliferating cell nuclear antigen gene in erythroleukemia cell line K562.

OBJECTIVE: To investigate the effect of total flavonoids of Hedysarum polybotry on the proliferation, cell cycle, and expressions of p21(Ras) and proliferating cell nuclear antigen (PCNA) gene in erythroleukemia cell line K562. METHODS: The effect of total flavonoids of Hedysarum polybotry on K562 cell line survival was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) reduction assay. The time- and dose-dependent manner was also observed. The cell cycle and apoptosis were analyzed with flow cytometry (FCM). The immunocytochemistry method was applied to quantitatively analyze the effects of flavonoids of Hedysarum polybotry on changes p21(Ras) and PCNA gene expressions. RESULTS: Flavonoids of Hedysarum polybotry (20-100 µg/mL) significantly inhibited the proliferation of K562 cells in a time- and dose-dependent manner. After K562 cells were cultured for 48 h, total flavonoids of Hedysarum polybotry had no significant effect on the apoptosis of K562 cells but showed significantly inhibition (P<0.01), indicating that total flavonoids of Hedysarum polybotry could induce K562 cells arrested at G(0)/G(1) and G(2)/M phases. Compared with the control group, p21(Ras) and PCNA gene expressions were decreased significantly in K562 cells treated with total flavonoids of Hedysarum polybotry (40 and 80 µg/mL, respectively) for 48 h. CONCLUSION: The inhibitory effect on proliferation of K562 cells was observed in the groups treated with flavonoids of Hedysarum polybotry, which might be related to cells arresting.

Actions of genistein on contractile response of smooth muscle isolated from guinea pig gallbladder.

BACKGROUND: Defective contractile motility of the gallbladder is an important factor for gallstone formation. Estrogen might increase the risk of gallstones and cholecystitis, and estradiol inhibits the contractile activity of isolated strips of guinea pig gallbladder. The potential risks associated with hormone replacement therapy (HRT) include symptomatic gallstones. Phytoestrogen have been used to treat menopause syndromes by replacing traditional estrogen. This experiment aimed to determine the effects of the phytoestrogen genistein on the contractile response of smooth muscle strips isolated from guinea pig gallbladder and its possible mechanism of action. METHODS: Guinea pigs were sacrificed to remove the whole gallbladder. Two or three smooth muscle strips were cut longitudinally. Each strip was suspended in a tissue chamber containing Krebs solution. After 2 hours of equilibration, contractile response indexes were recorded. Different concentrations of genistein were added to the chamber and the contractile responses were measured. Each antagonist was added 2 minutes before genistein to study possible mechanisms. The effect of genistein on calcium-dependent contraction curves and biphasic contraction in calcium-free Krebs solution were measured. RESULTS: Genistein decreased the resting tension dose-dependently, and reduced the mean contractile amplitude and frequency in gallbladder strips. Ranitidine partly inhibited the effect of genistein, but methylene blue, Nomega-nitro-L-arginine, and propranolol hydrochloride did not influence this action. Genistein had no significant effects on calcium-dependent contraction. Genistein reduced the first contraction induced by acetylcholine chloride, but did not affect the second contraction caused by CaCl2. CONCLUSIONS: Genistein relaxed smooth muscle isolated from the gallbladder of guinea pigs and this might contribute to the formation of gallstones. The inhibitory action might be related to H2 receptors and the release of intracellular Ca2+ from sarcoplasmic reticulum. Replacing traditional estrogen with phytoestrogen to treat menopause syndromes may increase the risk of gallstone formation.

Effects of rhubarb on isolated gastric muscle strips of guinea pigs.

AIM: To study the effects of rhubarb (dried root of Rheum officinale Baill.) on contractile activity of isolated gastric muscle strips of guinea pigs and its possible mechanism. METHODS: A total of 48 guinea pigs were killed to remove the whole stomach. Then, the stomach was opened and the mucosal layer was removed. Parallel to the circular fibers, muscle strips were cut from the body. Each isolated gastric muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution, constantly warmed by water jacket at 37 degrees and bubbled continuously with a mixed gas of 950 mL/L O2 and 50 mL/L CO2. After being incubated for 1 h with 1 g tension, rhubarb of varied concentrations (1%, 2%, 7%, 20% and 70%) was added cumulatively into the tissue chamber at intervals of 2 min. Atropine (10(-6) mol/L) or isoptin (5 x 10(-8) mol/L) or hexamethonium (10(-5) mol/L) was given 2 min before the administration of rhubarb. The isometrical response was measured with an ink-writing recorder. RESULTS: Rhubarb dose dependently increased the resting tension of gastric body circular muscle (CM) (r = 0.726, P<0.05). Atropine (r = 0.829, P<0.05), isoptin (r = 0.764, P<0.05) and hexamethonium (r = 0.797, P<0.05) did not affect its action in a dose-related manner. Atropine apparently reduced the increasing action of 1%, 3%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Isoptin inhibited the effect of 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Hexamethonium reduced the increasing action of 1%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Rhubarb increased the contractile frequency of CM of body. While atropine, isoptin and hexamethonium did not inhibit the contractile frequency of gastric body CM in comparison with rhubarb at the same concentration, rhubarb at the highest concentration (100%) decreased the mean contractile amplitude of gastric body CM. Atropine, isoptin and hexamethonium did not affect the mean contractile amplitude of gastric body CM compared to rhubarb at the same concentration. CONCLUSION: Rhubarb has exciting actions on isolated gastric smooth muscle strips of guinea pig. The exciting action of rhubarb is partly mediated via cholinergic M receptor, cholinergic N receptor and L-type calcium channel.

Effect of rhubarb on contractile response of gallbladder smooth muscle strips isolated from guinea pigs.

AIM: To investigate the effect of rhubarb on contractile response of isolated gallbladder muscle strips from guinea pigs and its mechanism. METHODS: Guinea pigs were killed to remove the whole gallbladder. Two or three smooth muscle strips (8 mm x 3 mm) were cut along the longitudinal direction. The mucosa on each strip was carefully removed. Each longitudinal muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution (37 degrees), bubbled continuously with 950 mL/L O(2) and 50 mL/L CO(2). The resting tension (g), mean contractile amplitude (mm), and contractile frequency (waves/min) were simultaneously recorded on recorders. After 2-h equilibration, rhubarb (10, 20, 70, 200, 700, 1,000 g/L) was added cumulatively to the tissue chamber in turns every 2 min to observe their effects on gallbladder. Antagonists were given 3 min before administration of rhubarb to investigate the possible mechanism. RESULTS: Rhubarb increased the resting tension (from 0 to 0.40+/-0.02, P<0.001), and decreased the mean contractile amplitude (from 5.22+/-0.71 to 2.73+/-0.41, P<0.001). It also increased the contractile frequency of the gallbladder muscle strips in guinea pigs (from 4.09+/-0.46 to 6.08+/-0.35, P<0.001). The stimulation of rhubarb on the resting tension decreased from 3.98+/-0.22 to 1.58+/-0.12 by atropine (P<0.001), from 3.98+/-0.22 to 2.09+/-0.19 by verapamil (P<0.001) and from 3.98+/-0.22 to 2.67+/-0.43 by phentolamine (P<0.005). But the effect was not inhibited by hexamethonium (P>0.05). In addition, the action of mean amplitude and frequency was not inhibited by the above antagonists. CONCLUSION: Rhubarb can stimulate the motility of isolated gallbladder muscle strips from guinea pigs. The stimulation of rhubarb might be relevant with M receptor, Ca(2+) channel and alpha receptor partly.