AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analys...AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining.Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase.The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P<0.05).SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P<0.05).Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P>0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.展开更多
Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical ...Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical constituents and in vitro antibacterial activity of methanol and aqueous extracts of Psidium guajava leaves and stem bark on Escherichia coli, Salmonella typhi, Staphylococcus aureus and Proteus sp. in Ugbokolo, Nigeria. Materials and Methods: The phytochemical screening of the plant materials for various bioactive components was conducted between July and December, 2019 using standard laboratory techniques. The extracts were purified using column chromatography. The identity of the test isolates were confirmed using morphological characteristics, gram stain, motility and appropriate biochemical tests such as indole, catalase, coagulase, triple sugar iron agar. The susceptibility of the isolates to each bioactive component was determined using the agar well diffusion method. The broth dilution method was employed for the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. Results: The result of the study showed the presence of phenol, tannins, flavonoids and saponins as bioactive compounds. The antibacterial susceptibility of the isolates to aqueous and methanol extracts of leaf and stem bark of Psidium guajava varied significantly (P Staphylococcus aureus was the most susceptible isolate at 200 mg/ml concentration with average zone of inhibition of 13.05 mm for leaf extract and 15.34 mm for stem bark extract. Proteus sp. is the least susceptible with average zone of inhibition of 8.88 mm for the leaf extract and 12.36 mm for the stem bark extract respectively. Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of aqueous and methanol extract of P. guajava leaf and stem bark showed that dilutions of various concentrations of aqueous and methanol extracts can inhibit and/or kill the isolates. Lower MIC (3.125 mg/ml) was shown by methanol extract than aqueous extract. MBC of methanol extract ranges between 6.25 - 25.0 mg/ml. Statistical analysis of the result showed methanol extract is more effective than aqueous extract while the stem bark of the plant showed higher efficacy than the leaf. Conclusion: The findings of the study imply that the extract of Psidium guajava has shown promising properties against tested microorganisms. Further study of the extract is therefore recommended.展开更多
基金Supported by National Science and Technology Key Project for the Development of New Drugs in China,No. 2009ZX09103-422
文摘AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining.Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase.The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P<0.05).SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P<0.05).Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P>0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.
文摘Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical constituents and in vitro antibacterial activity of methanol and aqueous extracts of Psidium guajava leaves and stem bark on Escherichia coli, Salmonella typhi, Staphylococcus aureus and Proteus sp. in Ugbokolo, Nigeria. Materials and Methods: The phytochemical screening of the plant materials for various bioactive components was conducted between July and December, 2019 using standard laboratory techniques. The extracts were purified using column chromatography. The identity of the test isolates were confirmed using morphological characteristics, gram stain, motility and appropriate biochemical tests such as indole, catalase, coagulase, triple sugar iron agar. The susceptibility of the isolates to each bioactive component was determined using the agar well diffusion method. The broth dilution method was employed for the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. Results: The result of the study showed the presence of phenol, tannins, flavonoids and saponins as bioactive compounds. The antibacterial susceptibility of the isolates to aqueous and methanol extracts of leaf and stem bark of Psidium guajava varied significantly (P Staphylococcus aureus was the most susceptible isolate at 200 mg/ml concentration with average zone of inhibition of 13.05 mm for leaf extract and 15.34 mm for stem bark extract. Proteus sp. is the least susceptible with average zone of inhibition of 8.88 mm for the leaf extract and 12.36 mm for the stem bark extract respectively. Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of aqueous and methanol extract of P. guajava leaf and stem bark showed that dilutions of various concentrations of aqueous and methanol extracts can inhibit and/or kill the isolates. Lower MIC (3.125 mg/ml) was shown by methanol extract than aqueous extract. MBC of methanol extract ranges between 6.25 - 25.0 mg/ml. Statistical analysis of the result showed methanol extract is more effective than aqueous extract while the stem bark of the plant showed higher efficacy than the leaf. Conclusion: The findings of the study imply that the extract of Psidium guajava has shown promising properties against tested microorganisms. Further study of the extract is therefore recommended.
