In Vitro Evaluation of Probiotic Potential of Lactic Acid Bacteria Isolated from Yunnan De'ang Pickled Tea.

This study aimed to investigate the probiotic potential of lactic acid bacteria (LAB) strains isolated from De'ang pickled tea, a traditional food consumed by the De'ang nationality of Yunnan, China. Twenty-six LAB strains isolated from De'ang pickled tea were subjected to identification based on 16S rRNA gene sequence analysis. Twenty-four belonged to Lactobacillus plantarum, one belonged to Enterococcus casseliflavus, and one belonged to Lactobacillus acidophilus. Eighteen out of 26 LAB strains which showed a higher capability to tolerate simulated gastrointestinal juices were chosen to further evaluate their probiotic properties. Varied adhesive abilities and auto-aggregative capacities of selected LAB strains were dependent on species and even strains. All tested LAB strains were resistant to kanamycin, streptomycin, gentamycin, and vancomycin and sensitive to tetracycline and chloramphenicol. Ten out of the 18 strains are resistant to ampicillin, and the remaining strains are sensitive to ampicillin; 4 out of the 18 strains showed resistance to erythromycin. Compared to reference strain Lactobacillus rhamnosus strain GG, these LAB strains had a greater or comparative antimicrobial activity against Salmonella typhimurium or Escherichia coli. In contrast, eight out of the 18 strains suppressed growth of Shigella flexneri. Two L. plantarum strains, ST and STDA10, not only exhibited good probiotic properties but also showed a good ability of scavenging DPPH and ABTS+. This study suggests that L. plantarum ST and STDA10 could be used as potential probiotics applied in functional foods.

Effects of aqueous extracts of raw pu-erh tea and ripened pu-erh tea on proliferation and differentiation of 3T3-L1 preadipocytes.

Pu-erh tea has shown anti-obesity effects but little is known about its effect on proliferation and differentiation of preadipocytes. This study investigated the effects of the aqueous extracts of raw pu-erh tea and ripened pu-erh tea on proliferation and differentiation of murine 3T3-L1 preadiopocytes. We examined dose and time effects of both aqueous extracts on proliferation of 3T3-L1 preadipocytes. The contents of triglycerides in cytoplasm and the mRNA expression of critical transcriptional factors involved in differentiation were determined. Cytotoxicity and apoptosis rate of preadipocytes by pu-erh tea extracts treatment were test for toxic and pro-apoptotic effects. Both aqueous extracts of pu-erh tea inhibited the proliferation of 3T3-L1 preadipocytes at the selected time points. At lower concentration of raw pu-erh tea extracts (less than 300 µg/ml) and ripened pu-erh tea extracts (less than 350 µg/ml), no significant cytotoxic and pro-apoptotic were observed. Ripened pu-erh tea was more effective with lower IC50 than raw pu-erh tea. Both extracts suppressed the differentiation and down-regulated the gene expression of peroxisome proliferator-activated receptor-γ and CCAAT/enhancer binding proteins-α. Therefore, these results indicate that both aqueous extracts of pu-erh tea can inhibit proliferation and differentiation with ripened pu-erh tea more potent. Polyphenol rich in both extracts may play a role in the inhibition of proliferation and differentiation of 3T3-L1 preadipocytes.

Protective effects of aucubin on H2O2-induced apoptosis in PC12 cells.

The present study investigated the neuroprotective effects of aucubin on hydrogen peroxide (H2O2)-induced apoptosis in PC12 cells. Exposure of PC12 cells to 0.25 mm H2O2 induced a leakage of lactate dehydrogenase and decreased cell viability, as shown by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In a dose over 0.1 mm, aucubin increased PC12 cellular viability and markedly attenuated H2O2-induced apoptotic cell death. Quantitation of apoptosis by flow cytometry indicated that aucubin inhibited H2O2-induced apoptosis in PC12 cells. Nuclear damage was alleviated by aucubin, as shown by Hoechst staining. In addition, the levels of malondialdehyde were reduced and the activity of superoxide dismutase, catalase and glutathione peroxidase was augmented in these cells. These results indicated that aucubin inhibited H2O2-induced apoptosis in PC12 cells through regulation of the endogenous oxidant-antioxidant balance. Our results suggest that aucubin is a potential protective agent for the treatment of oxidative-stress-induced neurodegenerative disease.

Effect of pu-erh tea on body fat and lipid profiles in rats with diet-induced obesity.

The antiobesity and antihyperlipidaemic effects of pu-erh tea in rats with high fat diet (HFD)-induced obesity were investigated. Male Sprague-Dawley rats were randomly divided into five groups and fed varying diets for an 8-week period: control diet, HFD, and HFD supplemented with low, moderate or high doses of pu-erh tea extract (0.5 g, 2 g and 4 g/kg BW/day, respectively). Pu-erh tea significantly reduced the total body weight and the weight of various adipose pads. Pu-erh tea administration also significantly lowered plasma total cholesterol, triglyceride concentrations and low-density lipoprotein-cholesterol levels in rats with HFD-induced obesity, but did not affect high-density lipoprotein-cholesterol levels. Moreover, pu-erh tea significantly increased lipoprotein lipase, hepatic lipase and hormone-sensitive lipase activities in epididymal fat tissue in rats with HFD-induced obesity. Analysis of real-time reverse transcription-polymerase chain reaction results indicated that pu-erh tea significantly enhanced mRNA levels of hormone-sensitive lipase in rats with HFD-induced obesity. These results suggest that pu-erh tea attenuated visceral fat accumulation and improved hyperlipidemia in a rat model of HFD-induced obesity.

Protective effect of Acanthopanax senticosus extract against endotoxic shock in mice.

AIM OF THE STUDY: In this study, we evaluated protective effect of Acanthopanax senticosus extract (ASE) and a possible signaling pathway involved during endotoxic shock induced by intraperitoneal injection lipopolysaccharide (LPS) and D-galactosamine (D-GalN) in BALB/c mice. MATERIALS AND METHODS: Mice were intraperitoneal administrated with ASE (100, 200 or 400mg/kg) prior to injection of 50 microg/kg LPS and 1g/kg D-GalN. The levels of tumor necrosis-alpha (TNF-alpha) and interleukin-10 (IL-10) in serum and liver. Nitric oxide (NO) production in serum and inducible nitric oxide synthase (iNOS) protein level were investigated. Nuclear factor-kappa B (NF-kappaB) activation in liver was determined. Furthermore, we evaluated the effect of ASE pretreatment on infiltration of inflammatory cells into the heart, liver and lung of mice. RESULTS: Treatment of mice with ASE prior to LPS/D-GalN injection significantly improved the survival rate. ASE pretreatment inhibited the elevation of TNF-alpha in serum and liver. ASE also decreased iNOS level in liver and the overproduction of nitric oxide (NO) in serum. In addition, IL-10 levels in serum and liver were markedly enhanced. ASE pretreatment inhibited NF-kappaB activation in liver of mice. Moreover, infiltration of inflammatory cells into the heart, liver and lung of mice was also attenuated by ASE pretreatment. CONCLUSIONS: These results suggested that ASE protected mice against LPS/D-GalN-induced endotoxic shock involving inhibition of NF-kappaB activation, which caused down-regulation of TNF-alpha and involved up-regulation of IL-10. Acanthopanax senticosus may thus prove beneficial in the prevention of endotoxic shock.

Acanthopanax senticosus suppresses reactive oxygen species production by mouse peritoneal macrophages in vitro and in vivo.

Excess production of reactive oxygen species by macrophages has been implicated in many inflammatory diseases. The present study investigated the inhibitory effect of the stem bark extract of Acanthopanax senticosus on the production of superoxide anion and hydrogen peroxide in mouse peritoneal macrophages in vitro and in vivo. Exposure of mouse peritoneal macrophages to A. senticosus extract significantly suppressed superoxide anion production induced by zymosan in a dose-dependent manner. Similarly, exposure of mouse peritoneal macrophages to A. senticosus extract significantly inhibited hydrogen peroxide production induced by phorbol 12-myristate 13-acetate (PMA) in a dose-dependent manner. Intraperitoneal administration of A. senticosus extract to KM mice reduced the ex vivo production of zymosan induced-superoxide anion and PMA-induced hydrogen peroxide by their peritoneal macrophages. Exposure to A. senticosus extract did not affect the cell viability or systemic toxicity. A. senticosus inhibited reactive oxygen species production by mouse peritoneal macrophages in vitro and in vivo and may be partly responsible for the antiinflammatory function.

Inhibition of inducible nitric oxide synthase by Acanthopanax senticosus extract in RAW264.7 macrophages.

AIM OF THE STUDY: The herb Acanthopanax senticosus (Siberian ginseng) has long been used as a traditional medicine. However, little is known about anti-inflammatory effects and its mechanisms of action. Excess production of nitric oxide (NO) is one of the characteristics of inflammation. In this study we examined the effects of A. senticosus extract (ASE) on NO production and inducible nitric oxide synthase (iNOS) gene expression in lipopolysaccharide (LPS) plus interferon-gamma (IFN-gamma)-stimulated RAW264.7 macrophages and investigated its mechanisms of anti-inflammatory activity. MATERIALS AND METHODS: RAW264.7 macrophages were treated with 10 microg/ml LPS plus 20U/ml IFN-gamma in the presence or absence of ASE. NO production and iNOS gene expression were investigated. We further evaluated the effect of ASE on oxidative stress-sensitive transcription nuclear factor-kappa B (NF-kappaB) activation. RESULTS: ASE significantly suppressed NO production and iNOS gene expression in a dose-dependent manner. ASE also reduced DNA-binding activity of NF-kappaB in LPS plus IFN-gamma stimulated RAW264.7 macrophages. Further studies indicated that LPS plus IFN-gamma-induced inhibitory factor-kappa B alpha (I-kappaBalpha) degradation and p65 nuclear translocation were inhibited in RAW264.7 macrophages exposed to ASE. Moreover, ASE inhibited the LPS plus IFN-gamma mediated increase in intracellular peroxides production. CONCLUSIONS: These results suggest ASE suppresses iNOS gene expression through the inhibition of intracellular peroxides production, which has been implicated in the activation of NF-kappaB.

Acanthopanax senticosus inhibits nitric oxide production in murine macrophages in vitro and in vivo.

Excess nitric oxide (NO) production has been implicated in inflammatory diseases. The present study investigated the inhibitory effect of the stem bark extract of Acanthopanax senticosus (A. senticosus) on NO production in murine macrophages in vitro and in vivo. In vitro exposure of RAW264.7 cells to 1, 10, 50, 100, 250, 500 and 1000 microg/mL of A. senticosus extract significantly suppressed NO production induced by lipopolysaccharide (LPS) and interferon gamma (IFN-gamma) in a dose-dependent manner. In vitro exposure of mouse resident peritoneal macrophages to 1, 10, 100 and 1000 microg/mL of A. senticosus extract significantly suppressed NO production induced by LPS and IFN-gamma in a dose-dependent manner. In vivo administration of A. senticosus extract (50, 100 and 200 mg/kg) to KM mice dose-dependently inhibited LPS and IFN-gamma induced production of NO in isolated mouse peritoneal macrophages ex vivo. Exposure to A. senticosus extract had no effect on cell viability and systemic toxicity. The results demonstrated that the stem bark extract of A. senticosus extract inhibits NO production in murine macrophages in vitro and in vivo.