We extracted marine low-temperature lysozyme (MLTL),a novel lysozyme,from a marine microorganism through fermentation.Our previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity thr...We extracted marine low-temperature lysozyme (MLTL),a novel lysozyme,from a marine microorganism through fermentation.Our previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis.In this study,we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro.Using zebrafish embryos as an in vivo study model,we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent manner and that 400 μg/ml MLTL was sufficient to block the growth of SIVs.An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation,migration and tube formation of HUVECs in a dose-dependent manner.Interestingly,assays by flow cytometry and DNA electrophoresis indicated that MLTL was able to induce apoptosis of HUVECs.Moreover,further study demonstrated that the disruption of intracellular Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs.Taken together,the results of this study demonstrate for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces apoptosis through regulation of cellular Ca2+ levels.The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested that MLTL may be a promising new antiangiogenic agent for use in cancer therapy.展开更多
Aim To research therapeutical effect of marine lysozyme suppository on bacterial vaginitis caused by S. aureus and E. coll. Methods Lysozyme obtained from concha ostreae which were used to preparate marine lyso- zyme ...Aim To research therapeutical effect of marine lysozyme suppository on bacterial vaginitis caused by S. aureus and E. coll. Methods Lysozyme obtained from concha ostreae which were used to preparate marine lyso- zyme suppository. The identification and test of suppository was in line with the standards stated in Chinese pharma- coperia（2010 edition）. After determined its quality control, we studied its therapeutical effect on bacterial vaginitis which caused by S. aureus and E. coli, by vaginitis model in rats infection of S. aureus bacteria and E. coli. Results The preparation technology of marine lysozyme suppository was simple, convenient and clinically effective. The marine lysozyme suppository was delivered by dose 0.5, 0.25, 0. 125 g ~ kg-1, the cure rates of S. aureus infec- tion were 80% , 50% and 30% , respectively, the cure rates of E. coli infection were 90% , 60% and 30% re- spectively, the cure rates of mixed infection were 92.9% , 82. 1% and 92.9% respectively. Marine lysozyme sup- pository had an outstanding therapeutical effect on bacterial vaginitis which caused by S. aureus and E. coll. Con- clusion The preparative process of marine lysozyme suppository was practicable, and it had a good therapeutic effect on bacterial vaginitis caused by S. aureus and E. coll.展开更多
G-protein coupled receptors （GPCRs） class C represent a distant group among the large family of GPCRs. This class includes the receptors for the main neurotransmitters, glutamate and gamma-aminobutyric acid （GABA）...G-protein coupled receptors （GPCRs） class C represent a distant group among the large family of GPCRs. This class includes the receptors for the main neurotransmitters, glutamate and gamma-aminobutyric acid （GABA）, and the receptors for Ca2＋, some taste and pheromone molecules, as well as some orphan receptors. Like any other GPCRs, these receptors possess a heptahelical domain （HD） involved in heterotrimeric G-protein activation, but most of them also have a large extracellular domain （VFT） responsible for agonist recognition and binding. These receptors are dimers, either homo or heterodimers. Then whereas have mGluRs is homodimers, GABAB receptor was the first heteromeric G-protein coupled receptor （GPCR） identified. Indeed, both GB1 and GB2 subunits appear necessary to get a functional GABAB receptor. We have demonstrated that the interactions be- tween VFT domain of both GB1 and GB2 were important for receptor activation. We have also shown the dynamic movement of trans-membrane of mGluRs within dimers. Then we have found that the GABAB receptor induced acti- vation of ERK1/2/CREB and protected neurons from apoptosis by trans-activating IGF-1R. We have also demon- strated that GABAB receptor activation has been modulated by the dynamic protein-protein interactions between re- ceptors and its downstream signal proteins such as FAK1 and Rap l. Finally, we have performed the HTS screening and found the first negative allosteric modulator for GABAB receptors.展开更多
基金Supported by the National High Technology Research and Development Program (863 Program) (No.2003AA625070)the Research Fund Program of Qingdao University (No.20051102)
文摘We extracted marine low-temperature lysozyme (MLTL),a novel lysozyme,from a marine microorganism through fermentation.Our previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis.In this study,we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro.Using zebrafish embryos as an in vivo study model,we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent manner and that 400 μg/ml MLTL was sufficient to block the growth of SIVs.An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation,migration and tube formation of HUVECs in a dose-dependent manner.Interestingly,assays by flow cytometry and DNA electrophoresis indicated that MLTL was able to induce apoptosis of HUVECs.Moreover,further study demonstrated that the disruption of intracellular Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs.Taken together,the results of this study demonstrate for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces apoptosis through regulation of cellular Ca2+ levels.The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested that MLTL may be a promising new antiangiogenic agent for use in cancer therapy.
文摘Aim To research therapeutical effect of marine lysozyme suppository on bacterial vaginitis caused by S. aureus and E. coll. Methods Lysozyme obtained from concha ostreae which were used to preparate marine lyso- zyme suppository. The identification and test of suppository was in line with the standards stated in Chinese pharma- coperia（2010 edition）. After determined its quality control, we studied its therapeutical effect on bacterial vaginitis which caused by S. aureus and E. coli, by vaginitis model in rats infection of S. aureus bacteria and E. coli. Results The preparation technology of marine lysozyme suppository was simple, convenient and clinically effective. The marine lysozyme suppository was delivered by dose 0.5, 0.25, 0. 125 g ~ kg-1, the cure rates of S. aureus infec- tion were 80% , 50% and 30% , respectively, the cure rates of E. coli infection were 90% , 60% and 30% re- spectively, the cure rates of mixed infection were 92.9% , 82. 1% and 92.9% respectively. Marine lysozyme sup- pository had an outstanding therapeutical effect on bacterial vaginitis which caused by S. aureus and E. coll. Con- clusion The preparative process of marine lysozyme suppository was practicable, and it had a good therapeutic effect on bacterial vaginitis caused by S. aureus and E. coll.
文摘G-protein coupled receptors （GPCRs） class C represent a distant group among the large family of GPCRs. This class includes the receptors for the main neurotransmitters, glutamate and gamma-aminobutyric acid （GABA）, and the receptors for Ca2＋, some taste and pheromone molecules, as well as some orphan receptors. Like any other GPCRs, these receptors possess a heptahelical domain （HD） involved in heterotrimeric G-protein activation, but most of them also have a large extracellular domain （VFT） responsible for agonist recognition and binding. These receptors are dimers, either homo or heterodimers. Then whereas have mGluRs is homodimers, GABAB receptor was the first heteromeric G-protein coupled receptor （GPCR） identified. Indeed, both GB1 and GB2 subunits appear necessary to get a functional GABAB receptor. We have demonstrated that the interactions be- tween VFT domain of both GB1 and GB2 were important for receptor activation. We have also shown the dynamic movement of trans-membrane of mGluRs within dimers. Then we have found that the GABAB receptor induced acti- vation of ERK1/2/CREB and protected neurons from apoptosis by trans-activating IGF-1R. We have also demon- strated that GABAB receptor activation has been modulated by the dynamic protein-protein interactions between re- ceptors and its downstream signal proteins such as FAK1 and Rap l. Finally, we have performed the HTS screening and found the first negative allosteric modulator for GABAB receptors.
