A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of ...A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of UAE were obtained by using Box-Behnken design of response surface methodology. Chromatography was carried out using a Kromasil C18 column by gradient elution with 0.1% phosphoric acid aqueous solution for HPLC-UV. All calibration curves showed good linear correlation coefficients （R^2〉0.999 6） and recoveries （from 97.3% to 104.9%） were acceptable. 1,1-diphenyl-2-picrylhydrazyl （DPPH） method was employed to test the antioxidant activity of the extract from the samples. The proposed method was successfully applied to quantifying eight components in nine samples of M.cordata, and significant variations of alkaloid contents and antioxidant aetivity of the samples from different habitats were demonstrated. It presents a powerful proof for the selection of the best sources to extract eight kinds of alkaloids.展开更多
OBJECTIVE Activation of the PINK1/Parkin-mediated autophagy pathway has been proposed to play a protective role in the development of neurological disorders through the elimination of damaged macromolecules or organel...OBJECTIVE Activation of the PINK1/Parkin-mediated autophagy pathway has been proposed to play a protective role in the development of neurological disorders through the elimination of damaged macromolecules or organelles.Exposure to excessive manganese(Mn) causes neurotoxicity and can produce a Parkinson disease(PD)-like neurological disorder.Mitochondrial dysfunction and oxidative stress are implicated in the mechanism of Mn induced neurotoxicity.The present study was designed to determine whether Dendrobium nobile Lindl.alkaloids(DNLA),a Chinese medicinal herb extract,confers protective function over Mn-induced cell toxicity,and to investigate whether the modulation of PINK1/Parkin-mediated autophagy is involved in the mechanism of DNLA-mediated cell protection over Mn toxicity.METHODS AND RESULTS Rat adrenal pheochromocytoma PC12 cells were utilized as an in vitro model of Mn cell toxicity.It was found that the treatment of the PC12 cells with Mn resulted in concentration-dependent cell death,accompanied by a decrease in mitochondrial respiration capacity and an increase in ROS generation,whereas pretreatment of cells with DNLA significantly alleviated cell toxicity induced by Mn and improved mitochondrial function and oxidative status.Mn treatment enhanced apoptotic cells along with a marked increase in the protein expression of Bax and a decrease in the expression of Bcl-2 protein.On the contrary,DNLA increased Bcl-2 expression,and concomitantly dramatically decreased the Bax/Bcl-2 ratio.Analysis of the expression of PINK1 and Parkin revealed that pretreatment of cells with DNLA significantly alleviated the decrease in protein levels of both PINK1 and Parkin caused by Mn.Furthermore,cells treated with Mn exhibited increased expression of LC3-Ⅱ and a decrease in accumulation of P62,which was noticeably reversed by the pretreatment of cells with DNLA.CONCLUSION DNLA inhibits Mn induced cytotoxicity,which may be mediated through modulating PINK1/Parkin-mediated autophagic flux and improving mitochondrial function.展开更多
Eight known alkaloids were isolated from jellyfish-derived fungus Aspergillus fumigatus SCSIO41214.These compounds were isolated by silica gel column chromatography,ostade-cylsilane(ODS),and high performance liquid ch...Eight known alkaloids were isolated from jellyfish-derived fungus Aspergillus fumigatus SCSIO41214.These compounds were isolated by silica gel column chromatography,ostade-cylsilane(ODS),and high performance liquid chromatography(HPLC).The structure of 1 was identified by performing a comprehensive analysis of spectroscopic data and X-ray diffraction for the first time.The structures of 2~8 were elucidated by spectroscopic methods and by comparison with data from the literature.In bioassay,compound 4 showed weak inhibitory activity against lipopolysaccharide(LPS)-induced nitric oxide(NO)in RAW264.7 cells at the concentration of 10μmol·L^(−1).展开更多
Abstract Macroautophagy(autophagy)is a′self-eating′machinery used by cells to degrade and recycle long-lived proteins and organelles via lysosomes.Dysregulation of autophagy plays a critical role in the pathogenesis...Abstract Macroautophagy(autophagy)is a′self-eating′machinery used by cells to degrade and recycle long-lived proteins and organelles via lysosomes.Dysregulation of autophagy plays a critical role in the pathogenesis of neurodegenerative disorders.Small molecule autophagy inducers protects against the toxic insults of aggregate-prone proteins by enhancing their clearance,thus leading towards the treatment of neurodegenerative disorders.Uncariarhynchophylla(Miq.)Jacks.(Gouteng in Chinese)is a commonly used Chinese herbal medicine for treating neurological diseases.We identified alkaloidscorynoxine B(Cory B)and corynoxine(Cory)from Gouteng as neuronal autophagy inducers,which promote the degradation of neurodegenerative proteins including alpha-synuclen(SNCA),amyloid precursor protein(APP)and tau,thus protecting neurons.Interestingly,the regulatory mechanisms of Cory B and Cory on autophagy are different.Cory B targets HMGB1-Beclin1 interaction to induce autophagy while Cory enhances autophagy via inhibition of mTOR pathway.The autophagy-enhancing Goutengalkaloids can be developed into therapeutic agents against neurodegenerative diseases such as Parkinson's disease and Alzheimer′s disease.展开更多
基金Project(20576142) supposed by the National Natural Science Foundation of China Project(2009DFA31270) supported by the International Cooperation Project of Ministry of Science and Technology of China
文摘A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of UAE were obtained by using Box-Behnken design of response surface methodology. Chromatography was carried out using a Kromasil C18 column by gradient elution with 0.1% phosphoric acid aqueous solution for HPLC-UV. All calibration curves showed good linear correlation coefficients （R^2〉0.999 6） and recoveries （from 97.3% to 104.9%） were acceptable. 1,1-diphenyl-2-picrylhydrazyl （DPPH） method was employed to test the antioxidant activity of the extract from the samples. The proposed method was successfully applied to quantifying eight components in nine samples of M.cordata, and significant variations of alkaloid contents and antioxidant aetivity of the samples from different habitats were demonstrated. It presents a powerful proof for the selection of the best sources to extract eight kinds of alkaloids.
文摘OBJECTIVE Activation of the PINK1/Parkin-mediated autophagy pathway has been proposed to play a protective role in the development of neurological disorders through the elimination of damaged macromolecules or organelles.Exposure to excessive manganese(Mn) causes neurotoxicity and can produce a Parkinson disease(PD)-like neurological disorder.Mitochondrial dysfunction and oxidative stress are implicated in the mechanism of Mn induced neurotoxicity.The present study was designed to determine whether Dendrobium nobile Lindl.alkaloids(DNLA),a Chinese medicinal herb extract,confers protective function over Mn-induced cell toxicity,and to investigate whether the modulation of PINK1/Parkin-mediated autophagy is involved in the mechanism of DNLA-mediated cell protection over Mn toxicity.METHODS AND RESULTS Rat adrenal pheochromocytoma PC12 cells were utilized as an in vitro model of Mn cell toxicity.It was found that the treatment of the PC12 cells with Mn resulted in concentration-dependent cell death,accompanied by a decrease in mitochondrial respiration capacity and an increase in ROS generation,whereas pretreatment of cells with DNLA significantly alleviated cell toxicity induced by Mn and improved mitochondrial function and oxidative status.Mn treatment enhanced apoptotic cells along with a marked increase in the protein expression of Bax and a decrease in the expression of Bcl-2 protein.On the contrary,DNLA increased Bcl-2 expression,and concomitantly dramatically decreased the Bax/Bcl-2 ratio.Analysis of the expression of PINK1 and Parkin revealed that pretreatment of cells with DNLA significantly alleviated the decrease in protein levels of both PINK1 and Parkin caused by Mn.Furthermore,cells treated with Mn exhibited increased expression of LC3-Ⅱ and a decrease in accumulation of P62,which was noticeably reversed by the pretreatment of cells with DNLA.CONCLUSION DNLA inhibits Mn induced cytotoxicity,which may be mediated through modulating PINK1/Parkin-mediated autophagic flux and improving mitochondrial function.
文摘Eight known alkaloids were isolated from jellyfish-derived fungus Aspergillus fumigatus SCSIO41214.These compounds were isolated by silica gel column chromatography,ostade-cylsilane(ODS),and high performance liquid chromatography(HPLC).The structure of 1 was identified by performing a comprehensive analysis of spectroscopic data and X-ray diffraction for the first time.The structures of 2~8 were elucidated by spectroscopic methods and by comparison with data from the literature.In bioassay,compound 4 showed weak inhibitory activity against lipopolysaccharide(LPS)-induced nitric oxide(NO)in RAW264.7 cells at the concentration of 10μmol·L^(−1).
文摘Abstract Macroautophagy(autophagy)is a′self-eating′machinery used by cells to degrade and recycle long-lived proteins and organelles via lysosomes.Dysregulation of autophagy plays a critical role in the pathogenesis of neurodegenerative disorders.Small molecule autophagy inducers protects against the toxic insults of aggregate-prone proteins by enhancing their clearance,thus leading towards the treatment of neurodegenerative disorders.Uncariarhynchophylla(Miq.)Jacks.(Gouteng in Chinese)is a commonly used Chinese herbal medicine for treating neurological diseases.We identified alkaloidscorynoxine B(Cory B)and corynoxine(Cory)from Gouteng as neuronal autophagy inducers,which promote the degradation of neurodegenerative proteins including alpha-synuclen(SNCA),amyloid precursor protein(APP)and tau,thus protecting neurons.Interestingly,the regulatory mechanisms of Cory B and Cory on autophagy are different.Cory B targets HMGB1-Beclin1 interaction to induce autophagy while Cory enhances autophagy via inhibition of mTOR pathway.The autophagy-enhancing Goutengalkaloids can be developed into therapeutic agents against neurodegenerative diseases such as Parkinson's disease and Alzheimer′s disease.
