AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones fr...AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones from cholecystectomy patients were incubated with hypericin or solvent. After 72 h, the stones were analysed for fluorescence(365 nm) and treated with 2-propanol/dimethyl sulfoxide for high performance liquid chromatography(HPLC) analysis. Rats with virtual gallbladder containing human cholesterol, mixed or pigment gallstones(VGHG) received 5 mg/kg hypericin or solvent and VGHG rats with cholesterol stones were given different hypericin doses(5-15 mg/kg). Twelve hours later, the stones were analysed at 365 nm. Biliary excretion and metabolites of hypericin were assessed in common bile duct(CBD) cannulated rats for 9 h using fluorospectrometry, HPLC and matrixassisted laser desorption/ionization-time-of-flight mass spectrometry(MALDI-TOF MS).RESULTS: Homogeneous high fluorescence was seen on cholesterol stones either pre-incubated with hypericin or extracted from VGHG rats receiving hypericin. Mixed stones showed a dotted fluorescent pattern, whereas pigment and solvent-treated ones lacked fluorescence. HPLC showed 7.68, 6.65 and 0.08 × 10^(-3) M of cholesterol in extracts from cholesterol, mixed, and pigment gallstones, respectively. Hypericin accounted for 2.0, 0.5 and 0.2 × 10-6 M in that order. On cholesterol stones from VGHG rats receiving different hypericin doses, a positive correlation was observed between dose and fluorescence. In the bile from CBD-cannulated rats, fluorescence represented 20% of the injected dose with two peaks in 9 h. HPLC analysis revealed that hypericin conjugates reached 60% of the peak area. By MALDI-TOF MS, hypericinglucuronide was detected. CONCLUSION: This study proves the potential use of hypericin for differential fluorescent detection of human gallstones regarding their chemical composition.展开更多
OBJECTIVE To investigate the therapeutic efficiency of an endogenous enzyme-NQO1 activated hypericin in photodynamic therapy.METHODS An endogenous enzyme-NQO1 responsive photo sensitizer was designed and synthesized b...OBJECTIVE To investigate the therapeutic efficiency of an endogenous enzyme-NQO1 activated hypericin in photodynamic therapy.METHODS An endogenous enzyme-NQO1 responsive photo sensitizer was designed and synthesized by conjugating aquinonebased ligand to a natural photosensitizer derived from Chinese herb.The photophysical and photochemical properties were investigated through UV-visible and fluorescence spectrophotometer,and the photodynamic activity was evaluated with MTT assay.RESULTS An endogenous enzyme-NQO1 activated hypericin was prepared and fully characterized with various spectroscopic methods.The electronic absorption was almost the same with the free hypericin,indicating the introducing of the ligand to hypericin has little effect to its ground state,while there is almost no detected fluorescence and reactive oxygen species(ROS)generation in PBS solution indicating the introducing of the ligand can effectively quench the fluorescence emission and ROS generation.The in vitro study showed that both compounds have almost no dark toxicity,but they are highlyphotocytoxic with an IC50 less than 1μmol·L-1 against A549 cell lines indicating the modified compound can be activated in the intracellular environment.CONCLUSION A simple and efficient hypericin-based activated photosensitizer was prepared.The ROS generation was quenched in PBS solution and it would be activated inside A549 cell lines.It may be served as apromising tumor selective fluorescent probe and photosensitizer for targeted photodynamic therapy.展开更多
OBJECTIVE Hypericin,a powerful naturally photosensitizer in photodynamic therapy(PDT),is suitable for treating skin diseases involving excess capillary proliferation.In the present study,we aimed to evaluate the skin ...OBJECTIVE Hypericin,a powerful naturally photosensitizer in photodynamic therapy(PDT),is suitable for treating skin diseases involving excess capillary proliferation.In the present study,we aimed to evaluate the skin penetrability of a topically applied hypericin,expecting reducing the risk of prolonged skin photosensitivity,which often occurs after systemic administration.METHODS The Franz diffusion cell assay was performed to evaluate different penetration enhancers.In vivo studies,fluorescence microscopy was performed to examine the distribution of hypericin in the skin,macroscopic and microscopic analyses were also carried out to detect pathological changes in the skin after topical hypericin-PDT treatment.Immunohistochemistry was used to determine the expression of PECAM-1 in the treated skin.RESULTS 5% menthol facilitated hypericin penetrate the skin of nude mice most.The results of in vivo assays revealed that hypericin penetrated nude mice skin,spread to the dermis,and resulted in obvious photosensitivity reaction on the dermal capillaries.Moreover,skin injured by the photosensitive reaction induced by hypericin was replaced by normal skin 7 d after hypericin-PDT treatment.CONCLUSION Topical hypericin could penetrate nude mouse skin well and be great potential in PDT treatment of skin diseases.展开更多
Resistance against commonly used antibiotics is a serious clinical problem in recent medical practice. There exist several bacterial strains in which the possibilities of their inhibition are very limited due to multi...Resistance against commonly used antibiotics is a serious clinical problem in recent medical practice. There exist several bacterial strains in which the possibilities of their inhibition are very limited due to multidrug resistance. Antimicrobial photodynamic therapy (aPDT) represents an option how to effectively suppress the growth of resistant pathogens. In this work we have studied interactions of potent photosensitizer hypericin (Hyp) with hospital-related gram positive (Gram+) and gram negative (Gram-) bacterial strains and the effects of photodynamic activated Hyp on bacterial susceptibility and/or resistance of these strains to antibiotics. We demonstrated a significant influence of photoactivated Hyp on growth of Staphylococcus aureus and Enterococcus sp. We have also shown that it is extremely important to use the effective concentrations of Hyp for aPDT, which completely inhibit the growth of microorganisms. Otherwise, there appears an increase in resistance, probably due to the activation of efflux mechanisms, which are involved in the efflux of Hyp and antibiotics as well.展开更多
Purpose: To investigate the mechanism of the Ca2 + signaling in cultured human retinal pigment epithelial(RPE) cells with the protein kinase C(PKC) specific inhibitor-hypericin stimulation.Methods: Cultured human RP...Purpose: To investigate the mechanism of the Ca2 + signaling in cultured human retinal pigment epithelial(RPE) cells with the protein kinase C(PKC) specific inhibitor-hypericin stimulation.Methods: Cultured human RPE cells were analyzed using the fluorescence Ca2+ dye fluo-3 AM and laser scanning confocal microscope(LSCM) after stimulation with 100nM phorbol 12-myristate 13-acetate(PMA) and (or)5 concentrations of hypericin(1, 2, 3, 4 and 5 μM).Results: The normal fluorescence in RPE cells was strong and distributed throughout the cells. The nucleus appeared to be more fluorescent than the cytoplasm. After stimulation with PMA alone or 5 concentrations of hypericin, a rapid decrease in flurescence intensity was observed. There was no obvious difference in decreased curve among 5concentrations. However, after stimulation with a 24 hr preincubation of PMA and 5 concentrations of hypericin, a further decrease was not observed.Conclusion: Fluo-3 AM appears to be a good indicator of the change in Ca2+ occurring in RPE cells and hypericin is a strong inhibitor of Ca2 + influx channel. Hypericin has potential as a therapeutic drug for proliferative vitreoretinopathy(PVR), the inhibitory effect on PVR might be caused by blocking the PKC activity and inhibiting Ca2+ influxpathway.展开更多
Advances in biomimetic three-dimensional(3D) melanoma models have brought new prospects of drug screening and disease modeling, since their physiological relevancy for recapitulating in vivo tumor architectures is mor...Advances in biomimetic three-dimensional(3D) melanoma models have brought new prospects of drug screening and disease modeling, since their physiological relevancy for recapitulating in vivo tumor architectures is more accurate than traditional two-dimensional(2D) cell culture. Gelatin methacryloyl(GelMA) is widely used as a tissue-engineered scaffold hydrogel for 3D cell culture. In the present study, an in vitro 3D malignant melanoma model based on Gel MA was fabricated to evaluate the efficiency of hypericin(Hy)-loaded microemulsion(ME) in photodynamic therapy against melanoma. The ME was produced by the spontaneous emulsification method to enhance the bioavailability of Hy at tumor sites. Hy-loaded MEs were applied to a 3D malignant melanoma model made using 6% Gel MA and the co-culture of B16F10 and Balb/c 3T3 cells,followed by crosslinking using violet light(403 nm). The observation revealed excellent cell viability and the presence of F-actin cytoskeleton network. Hy-loaded MEs exhibited higher phototoxicity and cell accumulation(about threefold) than free Hy, and the cells cultured in the 3D system displayed lower susceptibility(about 2.5-fold) than those in 2D culture.These findings indicate that the developed MEs are potential delivery carriers for Hy;furthermore, Gel MA hydrogel-based modeling in polydimethylsiloxane(PDMS) molds is a user-friendly and cost-effective in vitro platform to investigate drug penetration and provide a basis for evaluating nanocarrier efficiency for skin cancer and other skin-related diseases.展开更多
The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra.and Hypericum scabrum L.species which are naturally distributed in the flora of Siirt province,Turkey.Hyperi...The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra.and Hypericum scabrum L.species which are naturally distributed in the flora of Siirt province,Turkey.Hypericin contents of Hypericum species grown in different geographical aspects(North,South,East,and West),and it was measured at different harvest times(full bloom-ing and post blooming period).In the current study,it has been determined that total hypericin content varies considerably according to aspects,plant developmental stages(ontogenetic variance),and species.According to species x aspect interaction,the highest total hypericin content was recorded from the west aspect(3.13 mg/g)in Hypericum triquetrifolium,while,the lowest hypericin content was also obtained from the west aspect(1.22 mg/g)in Hypericum scabrum.When the highest total hypericin content was analyzed according to aspect x species x harvest time interaction,the highest total hypericin content was produced from Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g,while the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/g.In species x harvest time interaction,the highest total hypericin content was obtained from the full bloom(3.10 mg/g)harvest in Hypericum triquetrifolium,while the lowest hypericin was obtained from the full bloom(1.26 mg/g)harvest in Hypericum scabrum.The data suggest that the aver-age total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and 1.28 mg/g in Hypericum scabrum.展开更多
采用用计算化学方法研究金丝桃素分子结构特征,并用分子动力学方法研究其与HIV蛋白酶的相互作用,探讨其可能的抗HIV病毒作用机理.结果表明,金丝桃素分子结构具有刚性特征,与HIV蛋白酶在酶的催化活性位点与ASP-A25 and ASP-B25以氢键作...采用用计算化学方法研究金丝桃素分子结构特征,并用分子动力学方法研究其与HIV蛋白酶的相互作用,探讨其可能的抗HIV病毒作用机理.结果表明,金丝桃素分子结构具有刚性特征,与HIV蛋白酶在酶的催化活性位点与ASP-A25 and ASP-B25以氢键作用相结合.展开更多
基金Supported by Research Foundation-Flanders(FWO)the KU Leuven Molecular Small Animal Imaging Center Mo SAIC,No.KUL EF/05/08+4 种基金the center of excellence in vivo molecular imaging research(IMIR)KU Leuven projects,No.IOFHB/08/009 and No.IOF-HB/12/018the European Union,AsiaLink Cf P 2006-Europe Aid/123738/C/ACT/Multi-Proposal,No128-498/111National Natural Science Foundation of China,No.81071828Jiangsu Province Natural Science Foundation,No.BK2010594
文摘AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones from cholecystectomy patients were incubated with hypericin or solvent. After 72 h, the stones were analysed for fluorescence(365 nm) and treated with 2-propanol/dimethyl sulfoxide for high performance liquid chromatography(HPLC) analysis. Rats with virtual gallbladder containing human cholesterol, mixed or pigment gallstones(VGHG) received 5 mg/kg hypericin or solvent and VGHG rats with cholesterol stones were given different hypericin doses(5-15 mg/kg). Twelve hours later, the stones were analysed at 365 nm. Biliary excretion and metabolites of hypericin were assessed in common bile duct(CBD) cannulated rats for 9 h using fluorospectrometry, HPLC and matrixassisted laser desorption/ionization-time-of-flight mass spectrometry(MALDI-TOF MS).RESULTS: Homogeneous high fluorescence was seen on cholesterol stones either pre-incubated with hypericin or extracted from VGHG rats receiving hypericin. Mixed stones showed a dotted fluorescent pattern, whereas pigment and solvent-treated ones lacked fluorescence. HPLC showed 7.68, 6.65 and 0.08 × 10^(-3) M of cholesterol in extracts from cholesterol, mixed, and pigment gallstones, respectively. Hypericin accounted for 2.0, 0.5 and 0.2 × 10-6 M in that order. On cholesterol stones from VGHG rats receiving different hypericin doses, a positive correlation was observed between dose and fluorescence. In the bile from CBD-cannulated rats, fluorescence represented 20% of the injected dose with two peaks in 9 h. HPLC analysis revealed that hypericin conjugates reached 60% of the peak area. By MALDI-TOF MS, hypericinglucuronide was detected. CONCLUSION: This study proves the potential use of hypericin for differential fluorescent detection of human gallstones regarding their chemical composition.
基金The project supported by the general grant fund from Hong Kong Research Grant Committee(476912)Health and Medical Research Fund(13120442)Innovation and Technology Fund of Shenzhen(CXZZ20120619150627260)
文摘OBJECTIVE To investigate the therapeutic efficiency of an endogenous enzyme-NQO1 activated hypericin in photodynamic therapy.METHODS An endogenous enzyme-NQO1 responsive photo sensitizer was designed and synthesized by conjugating aquinonebased ligand to a natural photosensitizer derived from Chinese herb.The photophysical and photochemical properties were investigated through UV-visible and fluorescence spectrophotometer,and the photodynamic activity was evaluated with MTT assay.RESULTS An endogenous enzyme-NQO1 activated hypericin was prepared and fully characterized with various spectroscopic methods.The electronic absorption was almost the same with the free hypericin,indicating the introducing of the ligand to hypericin has little effect to its ground state,while there is almost no detected fluorescence and reactive oxygen species(ROS)generation in PBS solution indicating the introducing of the ligand can effectively quench the fluorescence emission and ROS generation.The in vitro study showed that both compounds have almost no dark toxicity,but they are highlyphotocytoxic with an IC50 less than 1μmol·L-1 against A549 cell lines indicating the modified compound can be activated in the intracellular environment.CONCLUSION A simple and efficient hypericin-based activated photosensitizer was prepared.The ROS generation was quenched in PBS solution and it would be activated inside A549 cell lines.It may be served as apromising tumor selective fluorescent probe and photosensitizer for targeted photodynamic therapy.
文摘OBJECTIVE Hypericin,a powerful naturally photosensitizer in photodynamic therapy(PDT),is suitable for treating skin diseases involving excess capillary proliferation.In the present study,we aimed to evaluate the skin penetrability of a topically applied hypericin,expecting reducing the risk of prolonged skin photosensitivity,which often occurs after systemic administration.METHODS The Franz diffusion cell assay was performed to evaluate different penetration enhancers.In vivo studies,fluorescence microscopy was performed to examine the distribution of hypericin in the skin,macroscopic and microscopic analyses were also carried out to detect pathological changes in the skin after topical hypericin-PDT treatment.Immunohistochemistry was used to determine the expression of PECAM-1 in the treated skin.RESULTS 5% menthol facilitated hypericin penetrate the skin of nude mice most.The results of in vivo assays revealed that hypericin penetrated nude mice skin,spread to the dermis,and resulted in obvious photosensitivity reaction on the dermal capillaries.Moreover,skin injured by the photosensitive reaction induced by hypericin was replaced by normal skin 7 d after hypericin-PDT treatment.CONCLUSION Topical hypericin could penetrate nude mouse skin well and be great potential in PDT treatment of skin diseases.
文摘Resistance against commonly used antibiotics is a serious clinical problem in recent medical practice. There exist several bacterial strains in which the possibilities of their inhibition are very limited due to multidrug resistance. Antimicrobial photodynamic therapy (aPDT) represents an option how to effectively suppress the growth of resistant pathogens. In this work we have studied interactions of potent photosensitizer hypericin (Hyp) with hospital-related gram positive (Gram+) and gram negative (Gram-) bacterial strains and the effects of photodynamic activated Hyp on bacterial susceptibility and/or resistance of these strains to antibiotics. We demonstrated a significant influence of photoactivated Hyp on growth of Staphylococcus aureus and Enterococcus sp. We have also shown that it is extremely important to use the effective concentrations of Hyp for aPDT, which completely inhibit the growth of microorganisms. Otherwise, there appears an increase in resistance, probably due to the activation of efflux mechanisms, which are involved in the efflux of Hyp and antibiotics as well.
基金The Project was supported by the National Nature Science Foundation of China(No.39970780)
文摘Purpose: To investigate the mechanism of the Ca2 + signaling in cultured human retinal pigment epithelial(RPE) cells with the protein kinase C(PKC) specific inhibitor-hypericin stimulation.Methods: Cultured human RPE cells were analyzed using the fluorescence Ca2+ dye fluo-3 AM and laser scanning confocal microscope(LSCM) after stimulation with 100nM phorbol 12-myristate 13-acetate(PMA) and (or)5 concentrations of hypericin(1, 2, 3, 4 and 5 μM).Results: The normal fluorescence in RPE cells was strong and distributed throughout the cells. The nucleus appeared to be more fluorescent than the cytoplasm. After stimulation with PMA alone or 5 concentrations of hypericin, a rapid decrease in flurescence intensity was observed. There was no obvious difference in decreased curve among 5concentrations. However, after stimulation with a 24 hr preincubation of PMA and 5 concentrations of hypericin, a further decrease was not observed.Conclusion: Fluo-3 AM appears to be a good indicator of the change in Ca2+ occurring in RPE cells and hypericin is a strong inhibitor of Ca2 + influx channel. Hypericin has potential as a therapeutic drug for proliferative vitreoretinopathy(PVR), the inhibitory effect on PVR might be caused by blocking the PKC activity and inhibiting Ca2+ influxpathway.
基金supported in part by the FAPESPINCTBio (Process 2014/50867-3)FAPESP-CEPOF (2013/072761)+1 种基金support by the Brigham Research InstituteLCV thanks FAPESP for financial support (Process 2013/01284-2)。
文摘Advances in biomimetic three-dimensional(3D) melanoma models have brought new prospects of drug screening and disease modeling, since their physiological relevancy for recapitulating in vivo tumor architectures is more accurate than traditional two-dimensional(2D) cell culture. Gelatin methacryloyl(GelMA) is widely used as a tissue-engineered scaffold hydrogel for 3D cell culture. In the present study, an in vitro 3D malignant melanoma model based on Gel MA was fabricated to evaluate the efficiency of hypericin(Hy)-loaded microemulsion(ME) in photodynamic therapy against melanoma. The ME was produced by the spontaneous emulsification method to enhance the bioavailability of Hy at tumor sites. Hy-loaded MEs were applied to a 3D malignant melanoma model made using 6% Gel MA and the co-culture of B16F10 and Balb/c 3T3 cells,followed by crosslinking using violet light(403 nm). The observation revealed excellent cell viability and the presence of F-actin cytoskeleton network. Hy-loaded MEs exhibited higher phototoxicity and cell accumulation(about threefold) than free Hy, and the cells cultured in the 3D system displayed lower susceptibility(about 2.5-fold) than those in 2D culture.These findings indicate that the developed MEs are potential delivery carriers for Hy;furthermore, Gel MA hydrogel-based modeling in polydimethylsiloxane(PDMS) molds is a user-friendly and cost-effective in vitro platform to investigate drug penetration and provide a basis for evaluating nanocarrier efficiency for skin cancer and other skin-related diseases.
基金This publication was supported by Award Number(2016-SİUFEB-23)from the Research Foundation of Siirt University,Turkey.
文摘The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra.and Hypericum scabrum L.species which are naturally distributed in the flora of Siirt province,Turkey.Hypericin contents of Hypericum species grown in different geographical aspects(North,South,East,and West),and it was measured at different harvest times(full bloom-ing and post blooming period).In the current study,it has been determined that total hypericin content varies considerably according to aspects,plant developmental stages(ontogenetic variance),and species.According to species x aspect interaction,the highest total hypericin content was recorded from the west aspect(3.13 mg/g)in Hypericum triquetrifolium,while,the lowest hypericin content was also obtained from the west aspect(1.22 mg/g)in Hypericum scabrum.When the highest total hypericin content was analyzed according to aspect x species x harvest time interaction,the highest total hypericin content was produced from Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g,while the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/g.In species x harvest time interaction,the highest total hypericin content was obtained from the full bloom(3.10 mg/g)harvest in Hypericum triquetrifolium,while the lowest hypericin was obtained from the full bloom(1.26 mg/g)harvest in Hypericum scabrum.The data suggest that the aver-age total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and 1.28 mg/g in Hypericum scabrum.