As the relevance between left and right brain neurons when transmitting electrical signals of umami taste is unknown,the aim of this work was to investigate responsive regions of the brain to the umami tastant monosod...As the relevance between left and right brain neurons when transmitting electrical signals of umami taste is unknown,the aim of this work was to investigate responsive regions of the brain to the umami tastant monosodium glutamate(MSG)by using scalp-electroencephalogram(EEG)to identify the most responsive brain regions to MSG.Three concentrations of MSG(0.05,0.12,0.26 g/100 mL)were provided to participants for tasting while recoding their responsive reaction times and brain activities.The results indicated that the most responsive frequency to MSG was at 2 Hz,while the most responsive brain regions were T4 CzA2,F8 CzA2,and Fp2 CzA2.Moreover,the sensitivity of the brain to MSG was significantly higher in the right brain region.This study shows the potential of using EEG to investigate the relevance between different brains response to umami taste,which contributes to better understanding the mechanism of umami perception.展开更多
Objective: To observe the effect of intraplantar injection of monosodium iodoacetate (MIA) on pain perception in rats and to investigate the role of transient receptor potential vanilloid type 1 (TRPV1) in the effect....Objective: To observe the effect of intraplantar injection of monosodium iodoacetate (MIA) on pain perception in rats and to investigate the role of transient receptor potential vanilloid type 1 (TRPV1) in the effect. Methods: Adult male Wistar rats were used in the experiment. 1) MIA was injected subcutaneously into the right hindpaw of rats, the low, medium, and high doses of MIA were 0.11, 0.33, and 1 mg, respectively, then the changes of paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing within 4 hours after MIA injection were measured. 2) Capsazepine (TRPV1 antagonist, 30 μg) was injected subcutaneously into the right hindpaw of rats at 2 hours after intraplantar injection of MIA (1 mg), then the changes of paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing within 1 hour after capsazepine injection were measured. Results: 1) The paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing decreased after intraplantar injection of MIA in rats and the effect lasted for at least 4 hours. 2) The MIA-induced reduction in paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing were significantly alleviated after intraplantar injection of capsazepine in rats. Conclusion: Intraplantar injection of MIA can produce thermal pain, mechanical pain, and spontaneous pain for more than 4 hours, which may be due to the TRPV1 activation caused by MIA.展开更多
A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-g...A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.展开更多
Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation...Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation-induced emission luminogens(AIEgens)can be used for highly specific imaging of MSU crystals to assist in the diagnosis of gout.First,we developed a series of luminogens(i.e.,tetraphenyl ethylene(TPE)-NH_(2),TPE-2NH_(2),TPE-4NH_(2),TPE-COOH,TPE-2COOH,TPE-4COOH,and TPE-Ketoalkyne),each of which was then evenly mixed with MSU crystals.Next,optimal fluorescence imaging of each of the luminogens was characterized by a confocal laser scanning microscope(CLSM).This approach was used for imaging standard samples of MSU,hydroxyapatite(HAP)crystals,and mixed samples with 1:1 mass ratio of MSU/HAP.We also imaged samples from mouse models of acute gouty arthritis,HAP deposition disease,and comorbidities of interest.Subsequently,CLSM imaging results were compared with those of compensated polarized light microscopy,and we assessed the biosafety of TPE-Ketoalkyne in the RAW264.7 cell line.Finally,CLSM time series and three-dimensional imaging were performed on MSU crystal samples from human gouty synovial fluid and tophi.As a promising candidate for MSU crystal labeling,TPE-Ketoalkyne was found to detect MSU crystals accurately and rapidly in standard samples,animal samples,and human samples,and could precisely distinguish gout from HAP deposition disease.This work demonstrates that TPE-Ketoalkyne is suitable for highly specific and timely imaging of MSU crystals in gouty arthritis and may facilitate future research on MSU crystal-related diseases.展开更多
Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these subs...Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins and minerals in our two products justify their umami taste and can be used as highly nutritional food flavour enhancers to prevent cardiovascular diseases, especially in the elderly.展开更多
Monosodium glutamate (MSG) was administrated to rats at doses of 0.6 and 1.6 mg/g body weight for 14 days. Body weight and relative liver and kidney weight of rats were significantly increased. On regard to liver func...Monosodium glutamate (MSG) was administrated to rats at doses of 0.6 and 1.6 mg/g body weight for 14 days. Body weight and relative liver and kidney weight of rats were significantly increased. On regard to liver functions, the activities of alanine aminotransferase (ALT) and γ glutamyle transferase (GGT) significantly increased in the serum, on MSG administration, meanwhile, serum total protein, albumin and serum total bilirubin significantly decreased. MSG had adverse effects on kidney functions as serum urea and serum creatinine were significantly increased. Vitamin C (0.3 mg/g body weight) and vitamin E (0.2 mg/g body weight) co-adminstrated with MSG, significantly restored the body weight and relative liver and kidney weights to control levels. In the presence of vitamin C and vitamin E the activities of ALT and GGT in the serum were also significantly reduced to become comparable with control trail. Consequently, serum total protein, albumin and serum total bilirubin were significantly increased in the serum, while serum urea and serum creatinine were significantly decreased after administration of each vitamin. The results showed that MSG at doses of 0.6 and 1.6 mg/g of body weight may cause an adverse effect on the hepatic and renal functions which might be due to oxidative stress induced by MSG on the liver and renal tissue. Supplementation of vitamin C and vitamin E was capable of ameliorating MSG-induced oxidative stress on hepatic and renal functions.展开更多
The title compound, bis( μ 2 aqua)(aqua)(3 carboxy acrylate) monosodium(Ⅰ), was synthesized in an ethanol water solution and its crystal structure was determined by means of X ray diffraction. The crystal is triclin...The title compound, bis( μ 2 aqua)(aqua)(3 carboxy acrylate) monosodium(Ⅰ), was synthesized in an ethanol water solution and its crystal structure was determined by means of X ray diffraction. The crystal is triclinic , space group P 1 with the cell parameters a =0 592 4(2) nm, b =0 635 7(3) nm, c =1 117 7(6) nm, α =104 18°, β =91 53°, γ =100 19°, V =0 400 6(3) nm 3, Z =2, the final R value is 0 033 5. The supramolecule is made up of coordination chains, which are further extended into a three dimensional network via the hydrogen bonding interactions.展开更多
The effects of oral administration of low doses of monosodium glutamate (MSG) on behavioral phenotypes, biomarkers of oxidative stress in the brain and liver enzymes in mice were evaluated in this study. Mice were tre...The effects of oral administration of low doses of monosodium glutamate (MSG) on behavioral phenotypes, biomarkers of oxidative stress in the brain and liver enzymes in mice were evaluated in this study. Mice were treated orally with MSG (100, 250 and 500 mg/kg) daily for 21 days before testing for behavioral phenotypes;memory, anxiety, spontaneous motor activity (SMA) and depression. Thereafter, the brain levels of malondialdehyde (MDA) and glutathione (GSH) as well as the activities of liver enzymes, aminotransferase (AST) and alanine aminotransferase (ALT) were determined spectrophotometrically. MSG did not produce significant (P?> 0.05) impairment of memory in the Y-maze test. It also failed to modify the behaviors of mice in the elevated plus maze and light/dark transition tests of animal models of anxiety. MSG had no significant effect on SMA but produced depressive-like symptoms in the forced swim test at a dose of 500 mg/kg. Moreover, it increased the levels of MDA and decreased GSH concentrations in brain tissues of mice. The activity of AST and ALT were elevated in the blood of MSG-treated mice suggesting liver injury. Taken together, these findings suggested that MSG induced oxidative stress in the brain and impaired liver functions but did not produce any behavioral abnormalities in mice at lower doses.展开更多
Objective: To study the therapeutic mechanism of Santeng Dingtong recipe (STDT) on monosodium urate crystal (MSU) induced rabbit arthritis Methods: Forty-two rabbits were randomly divided into six groups, 7 in each gr...Objective: To study the therapeutic mechanism of Santeng Dingtong recipe (STDT) on monosodium urate crystal (MSU) induced rabbit arthritis Methods: Forty-two rabbits were randomly divided into six groups, 7 in each group. Group 1 received 0.9% saline 2. 5 ml/kg per day by gastrogavage (ig) for 10 days; Group 2, 3 and 4 received STDT 0.125 g/kg, 1.0 g/kg and 8.0 g/kg per day respectively by ig for 10 days; Group 5 received colchicine 4. 5 mg/kg per day by ig for 4 days; and Group 6 was untreated. MSU crystals 10 mg /500ul containing polymyxin B 10 u/ml was injected into the knee joints of Group 1-5 to make rabbit arthritis models. Leukocytes in synovial lavage fluids was then counted and differentiated; pathological injury of synovial membranes was observed under HE staining; interleukin-1 beta (IL-1B), tumor necrosis factor alpha (TNFa) and leukotriene B4 (LTB4) content in synovial lavage fluids were determined by ELISA. Results: MSU caused a rapid leukocyte infiltration and increased production of IL-1B, TNFa and LTB4 2 hrs after intra-articular injection. STDT inhibited neutrophil infiltration in synovial fluids dose-dependently, protected the synovial membrane against pathological injury and reduced the production of IL-1B, TNFa and LTB4; while colchicine did not decrease the level of TNFa, but significantly inhibited neutrophil infiltration in synovial fluid and reduced the production of IL-11B and LTB4. Conclusion: STDT exerts an anti-inflammatory effect in rabbit model of acute MSU arthritis, its mechanism being probably due to the decrease of XL-1B, TNFa and LTB4 synthesis.展开更多
Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficac...Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80～120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy.展开更多
Although monosodium glutamate(MSG)is a widely used food additive,its safety and systemic side effects have not been fully clarified.The intestinal flora is closely associated with human health;however,it remains uncle...Although monosodium glutamate(MSG)is a widely used food additive,its safety and systemic side effects have not been fully clarified.The intestinal flora is closely associated with human health;however,it remains unclear whether MSG consumption can affect health by acting on the intestinal flora.In this study,serum biomarkers,intestinal structure,intestinal immunity,and intestinal flora were examined to investigate the effects of different doses of sodium glutamate on the body,intestinal function,and intestinal flora of mice.The results showed that 30 mg/kg MSG had no significant effect on serum C-reactive protein,trimethylamine N-oxide,angiotensin II,intestinal interleukin(IL)-1β,IL-6,tumor necrosis factor-α,secretory IgA and fecal albumin in mice,but also promoted intestinal development and regulated the intestinal flora.Moreover,1500 mg/kg MSG increased the risk of cardiovascular disease and damaged the intestinal structure and flora.In this study,MSG was also found to be healthier than salt at the equivalent sodium concentration.Collectively,these findings suggested that low doses of MSG were safe for mice and may have some health benefits as a probiotic by promoting intestinal development and regulating the intestinal flora.展开更多
基金supported by the National Natural Science Foundation of China(31972198,31622042)the National Key R&D Program of China(2016YFD0400803,2016YFD0401501)。
文摘As the relevance between left and right brain neurons when transmitting electrical signals of umami taste is unknown,the aim of this work was to investigate responsive regions of the brain to the umami tastant monosodium glutamate(MSG)by using scalp-electroencephalogram(EEG)to identify the most responsive brain regions to MSG.Three concentrations of MSG(0.05,0.12,0.26 g/100 mL)were provided to participants for tasting while recoding their responsive reaction times and brain activities.The results indicated that the most responsive frequency to MSG was at 2 Hz,while the most responsive brain regions were T4 CzA2,F8 CzA2,and Fp2 CzA2.Moreover,the sensitivity of the brain to MSG was significantly higher in the right brain region.This study shows the potential of using EEG to investigate the relevance between different brains response to umami taste,which contributes to better understanding the mechanism of umami perception.
文摘Objective: To observe the effect of intraplantar injection of monosodium iodoacetate (MIA) on pain perception in rats and to investigate the role of transient receptor potential vanilloid type 1 (TRPV1) in the effect. Methods: Adult male Wistar rats were used in the experiment. 1) MIA was injected subcutaneously into the right hindpaw of rats, the low, medium, and high doses of MIA were 0.11, 0.33, and 1 mg, respectively, then the changes of paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing within 4 hours after MIA injection were measured. 2) Capsazepine (TRPV1 antagonist, 30 μg) was injected subcutaneously into the right hindpaw of rats at 2 hours after intraplantar injection of MIA (1 mg), then the changes of paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing within 1 hour after capsazepine injection were measured. Results: 1) The paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing decreased after intraplantar injection of MIA in rats and the effect lasted for at least 4 hours. 2) The MIA-induced reduction in paw withdrawal thermal latency, paw withdrawal mechanical threshold, and dynamic weight bearing were significantly alleviated after intraplantar injection of capsazepine in rats. Conclusion: Intraplantar injection of MIA can produce thermal pain, mechanical pain, and spontaneous pain for more than 4 hours, which may be due to the TRPV1 activation caused by MIA.
基金This work was supported by National Natural Science Foundation of China (No. 29504029).
文摘A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.
基金Thisworkwas supported by the Shanghai Science and Technology Committee(No.22dz1204700)the NationalKeyR&D Program of China(Nos.2020YFA0803800 and 2017YFE0132200)+2 种基金the National Natural Science Foundation of China(Nos.82072510,21907034,21788102,21525417,and 51620105009)the Natural Science Foundation of Guangdong Province(Nos.2019B030301003 and 2016A030312002)the Innovation and Technology Commission of Hong Kong(No.ITC-CNERC14S01).
文摘Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation-induced emission luminogens(AIEgens)can be used for highly specific imaging of MSU crystals to assist in the diagnosis of gout.First,we developed a series of luminogens(i.e.,tetraphenyl ethylene(TPE)-NH_(2),TPE-2NH_(2),TPE-4NH_(2),TPE-COOH,TPE-2COOH,TPE-4COOH,and TPE-Ketoalkyne),each of which was then evenly mixed with MSU crystals.Next,optimal fluorescence imaging of each of the luminogens was characterized by a confocal laser scanning microscope(CLSM).This approach was used for imaging standard samples of MSU,hydroxyapatite(HAP)crystals,and mixed samples with 1:1 mass ratio of MSU/HAP.We also imaged samples from mouse models of acute gouty arthritis,HAP deposition disease,and comorbidities of interest.Subsequently,CLSM imaging results were compared with those of compensated polarized light microscopy,and we assessed the biosafety of TPE-Ketoalkyne in the RAW264.7 cell line.Finally,CLSM time series and three-dimensional imaging were performed on MSU crystal samples from human gouty synovial fluid and tophi.As a promising candidate for MSU crystal labeling,TPE-Ketoalkyne was found to detect MSU crystals accurately and rapidly in standard samples,animal samples,and human samples,and could precisely distinguish gout from HAP deposition disease.This work demonstrates that TPE-Ketoalkyne is suitable for highly specific and timely imaging of MSU crystals in gouty arthritis and may facilitate future research on MSU crystal-related diseases.
文摘Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins and minerals in our two products justify their umami taste and can be used as highly nutritional food flavour enhancers to prevent cardiovascular diseases, especially in the elderly.
文摘Monosodium glutamate (MSG) was administrated to rats at doses of 0.6 and 1.6 mg/g body weight for 14 days. Body weight and relative liver and kidney weight of rats were significantly increased. On regard to liver functions, the activities of alanine aminotransferase (ALT) and γ glutamyle transferase (GGT) significantly increased in the serum, on MSG administration, meanwhile, serum total protein, albumin and serum total bilirubin significantly decreased. MSG had adverse effects on kidney functions as serum urea and serum creatinine were significantly increased. Vitamin C (0.3 mg/g body weight) and vitamin E (0.2 mg/g body weight) co-adminstrated with MSG, significantly restored the body weight and relative liver and kidney weights to control levels. In the presence of vitamin C and vitamin E the activities of ALT and GGT in the serum were also significantly reduced to become comparable with control trail. Consequently, serum total protein, albumin and serum total bilirubin were significantly increased in the serum, while serum urea and serum creatinine were significantly decreased after administration of each vitamin. The results showed that MSG at doses of 0.6 and 1.6 mg/g of body weight may cause an adverse effect on the hepatic and renal functions which might be due to oxidative stress induced by MSG on the liver and renal tissue. Supplementation of vitamin C and vitamin E was capable of ameliorating MSG-induced oxidative stress on hepatic and renal functions.
基金Supported by the Education Comm ission of Zhejiang Province(No. 2 0 0 10 12 9) and " 5 5 1" Distinguished PersonFoundation of Wenzhou.
文摘The title compound, bis( μ 2 aqua)(aqua)(3 carboxy acrylate) monosodium(Ⅰ), was synthesized in an ethanol water solution and its crystal structure was determined by means of X ray diffraction. The crystal is triclinic , space group P 1 with the cell parameters a =0 592 4(2) nm, b =0 635 7(3) nm, c =1 117 7(6) nm, α =104 18°, β =91 53°, γ =100 19°, V =0 400 6(3) nm 3, Z =2, the final R value is 0 033 5. The supramolecule is made up of coordination chains, which are further extended into a three dimensional network via the hydrogen bonding interactions.
文摘The effects of oral administration of low doses of monosodium glutamate (MSG) on behavioral phenotypes, biomarkers of oxidative stress in the brain and liver enzymes in mice were evaluated in this study. Mice were treated orally with MSG (100, 250 and 500 mg/kg) daily for 21 days before testing for behavioral phenotypes;memory, anxiety, spontaneous motor activity (SMA) and depression. Thereafter, the brain levels of malondialdehyde (MDA) and glutathione (GSH) as well as the activities of liver enzymes, aminotransferase (AST) and alanine aminotransferase (ALT) were determined spectrophotometrically. MSG did not produce significant (P?> 0.05) impairment of memory in the Y-maze test. It also failed to modify the behaviors of mice in the elevated plus maze and light/dark transition tests of animal models of anxiety. MSG had no significant effect on SMA but produced depressive-like symptoms in the forced swim test at a dose of 500 mg/kg. Moreover, it increased the levels of MDA and decreased GSH concentrations in brain tissues of mice. The activity of AST and ALT were elevated in the blood of MSG-treated mice suggesting liver injury. Taken together, these findings suggested that MSG induced oxidative stress in the brain and impaired liver functions but did not produce any behavioral abnormalities in mice at lower doses.
基金This program was supported by the National New Drugs Foundation(No.98-35-N-13)
文摘Objective: To study the therapeutic mechanism of Santeng Dingtong recipe (STDT) on monosodium urate crystal (MSU) induced rabbit arthritis Methods: Forty-two rabbits were randomly divided into six groups, 7 in each group. Group 1 received 0.9% saline 2. 5 ml/kg per day by gastrogavage (ig) for 10 days; Group 2, 3 and 4 received STDT 0.125 g/kg, 1.0 g/kg and 8.0 g/kg per day respectively by ig for 10 days; Group 5 received colchicine 4. 5 mg/kg per day by ig for 4 days; and Group 6 was untreated. MSU crystals 10 mg /500ul containing polymyxin B 10 u/ml was injected into the knee joints of Group 1-5 to make rabbit arthritis models. Leukocytes in synovial lavage fluids was then counted and differentiated; pathological injury of synovial membranes was observed under HE staining; interleukin-1 beta (IL-1B), tumor necrosis factor alpha (TNFa) and leukotriene B4 (LTB4) content in synovial lavage fluids were determined by ELISA. Results: MSU caused a rapid leukocyte infiltration and increased production of IL-1B, TNFa and LTB4 2 hrs after intra-articular injection. STDT inhibited neutrophil infiltration in synovial fluids dose-dependently, protected the synovial membrane against pathological injury and reduced the production of IL-1B, TNFa and LTB4; while colchicine did not decrease the level of TNFa, but significantly inhibited neutrophil infiltration in synovial fluid and reduced the production of IL-11B and LTB4. Conclusion: STDT exerts an anti-inflammatory effect in rabbit model of acute MSU arthritis, its mechanism being probably due to the decrease of XL-1B, TNFa and LTB4 synthesis.
基金supported by National Natural Science Foundation of China (No. 51373168)
文摘Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80～120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy.
基金supported by the Inner Mongolia Autonomous Region Science and Technology Achievement Transformation Project(CGZH2018035).
文摘Although monosodium glutamate(MSG)is a widely used food additive,its safety and systemic side effects have not been fully clarified.The intestinal flora is closely associated with human health;however,it remains unclear whether MSG consumption can affect health by acting on the intestinal flora.In this study,serum biomarkers,intestinal structure,intestinal immunity,and intestinal flora were examined to investigate the effects of different doses of sodium glutamate on the body,intestinal function,and intestinal flora of mice.The results showed that 30 mg/kg MSG had no significant effect on serum C-reactive protein,trimethylamine N-oxide,angiotensin II,intestinal interleukin(IL)-1β,IL-6,tumor necrosis factor-α,secretory IgA and fecal albumin in mice,but also promoted intestinal development and regulated the intestinal flora.Moreover,1500 mg/kg MSG increased the risk of cardiovascular disease and damaged the intestinal structure and flora.In this study,MSG was also found to be healthier than salt at the equivalent sodium concentration.Collectively,these findings suggested that low doses of MSG were safe for mice and may have some health benefits as a probiotic by promoting intestinal development and regulating the intestinal flora.
