白内障目前已成为世界上致盲的首位原因,而糖尿病性白内障是其中的重要发病类型。本研究通过单细胞电泳分析(single cell gel assay,SCG)来研究补益肝肾法对链脲佐菌素糖尿病大鼠晶状体上皮细胞 DNA 的影响,以阐明其作用机理。材料与方...白内障目前已成为世界上致盲的首位原因,而糖尿病性白内障是其中的重要发病类型。本研究通过单细胞电泳分析(single cell gel assay,SCG)来研究补益肝肾法对链脲佐菌素糖尿病大鼠晶状体上皮细胞 DNA 的影响,以阐明其作用机理。材料与方法1 动物雄性 Wistar 大鼠,65只,体重(271.00±23.11)g,中国医学科学院实验动物研究所提供。2 药物补益肝肾中药复方(生地30g 山萸肉30g 白芍15g 草决明15g 女贞子10g 旱莲草10g 知母10g)浓缩药液由天津中医学院第二附属医院制剂科提供,每毫升含生药2g。维生素 E 注射液(5mg/ml,上海第九制药厂,批号:961101)。展开更多
The commercially available inbred obesity-prone C57BL/6J （B6） and outbred stock ICR mice （3-week old） purchased from a breeder of Beijing were weaned onto high-fat diet （HFD）, HFD-3% fructose water （HFDF） and ...The commercially available inbred obesity-prone C57BL/6J （B6） and outbred stock ICR mice （3-week old） purchased from a breeder of Beijing were weaned onto high-fat diet （HFD）, HFD-3% fructose water （HFDF） and standard rodent chow, respectively. After exposure to the diets for six weeks, HFD and HFDF fed mice were injected intraperitoneally with streptozotocin （STZ, 100mg/kg body weight） and kept on the same diet for next four weeks. Body weight was recorded weekly. Non-fasting blood glucose levels of HFD and HFDF fed mice were measured before and after STZ injections. The body weight of HFD-fed and HFDF-fed B6 mice were significantly lower than that of the control, but body weight of HFD-fed and HFDF-fed ICR mice were significantly higher than that of the control. After injection of STZ, blood glucose levels were above the stardardized criterion （11 mmol/L） for the diabetes mouse model in both HFD and HFDF fed ICR mice, but reverse in B6 mice. The type 2 diabetes model was generated successfully in ICR but not in B6 mice, regardless of whether fructose was supplied. The current results indicated that ICR mouse is still a useful and economical strain for HFD-induced/STZ-treated type 2 diabetes model, and that some variation may occur in the genetic composition among B6 mice bred by different breeders.展开更多
AIM： To investigate the effect of Tangweian Jianji （TWAJJ） on the biomechanical and morphometrical remodeling of the upper gastrointestinal tract in diabetic rats. METHODS： Diabetes was induced in 27 rats by in- j...AIM： To investigate the effect of Tangweian Jianji （TWAJJ） on the biomechanical and morphometrical remodeling of the upper gastrointestinal tract in diabetic rats. METHODS： Diabetes was induced in 27 rats by in- jecting streptozotocin （40 mg/kg body weight）, the animals were then divided into three groups （n = 9 in each group）, i.e., diabetic control （DM）; high dose （10 g/kg, T1） and low dose （5 g/kg, T2）. Another 10 rats acted as normal controls （Control）. TWAJJ was admin- istered by gavage once daily. Blood glucose and serum insulin levels were measured. Circumferential length, wall thickness and opening angle were measured from esophageal, duodenal, jejunal and ileal ring segments. The residual strain was calculated from the morpho- metric data. Step-wise distension was carried out on esophageal and jejunal segments. The obtained data on the length, diameter and pressure changes were then used to calculate the circumferential and longitu- dinal stresses and strains. Real-time reverse transcrip- tion polymerase chain reaction was used to detect the receptor of advanced glycation end-products （RAGE） mRNA level in jejunal tissues. RESULTS： At the end of the experiment, the blood glucose level was significantly higher and the serum insulin level was significantly lower in DM, T1 and T2 groups than in the control group （Glucose： 30.23 ± 0.41 mmol/L, 27.48 ± 0.27 mmol/L and 27.84 ± 0.29 mmol/ L vs 5.05 ± 0.04 mmol/L, P = 1.65 x 10-16, P = 5.89 x 1019 and P = 1.63 x 10-Is, respectively; Insulin： 1.47 ± 0.32 °tg/L, 2.66 ± 0.44 pg/L, 2.03 ± 0.29 pg/L and 4.17 ± 0.54 pg/L, P = 0.0001, P = 0.029 and P = 0.025, re- spectively）. However, these levels did not differ among the DM, T1 and T2 groups. The wet weight per unit length, wall thickness and opening angle of esophageal and intestinal segments in the DM group were signifi- cantly higher than those in the control group （from P = 0.009 to P = 0.004）. These parameters in the T1 group were significantly lower than those in the DM group （wet weight, duodenum： 0.147 ± 0.003 g/cm vs 0.158 ± 0.001 g/cm, P = 0.047; jejunum, 0.127 ± 0.003 g/cm vs 0.151：1：0.002 g/cm, P = 0.017; ileum, 0.127 ± 0.004 g/cm vs 0.139 ± 0.003 g/cm, P = 0.046; wall thickness, esophagus： 0.84±0.03 mm vs 0.94 ± 0.02 ram, P = 0.014; duodenum： 1.27 ± 0.06 mm vs 1.39 ± 0.05 ram, P = 0.031; jejunum： 1.19 ± 0.07 mm vs 1.34 ± 0.04 mm, P = 0.047; ileum： 1.09 ± 0.04 mm vs 1.15 ± 0.03 mm, P = 0.049; opening angle, esophagus： 112.2 ± 13.2° vs 134.7 ± 14.7°, P = 0.027; duodenum： 105.9 ± 12.3° vs 123.1 ± 13.1°, P = 0.046; jejunum： 90.1 ± 15.4° vs 115.5 ± 13.3°, P = 0.044; ileum： 112.9 ± 13.4° vs 136.1 ± 17.1°, P = 0.035）. In the esophageal and jejunal segments, the inner residual stain was significantly smaller and the outer residual strain was larger in the DN group than in the control group （P = 0.022 and P = 0.035）. T1 treatment significantly restored this biomechanical alteration （P = 0.011 and P = 0.019）, but T2 treatment did not. Fur- thermore, the circumferential and longitudinal stiffness of the esophageal and jejunal wall increased in the DM group compared with those in the control group. T1, but not T2 treatment, significantly decreased the cir- cumferential wall stiffness in the jejunal segment （P = 0.012） and longitudinal wall stiffness in the esophageal segment （P = 0.023）. The mRNA level of RAGE was significantly decreased in the T1 group compared to that in the DN group （P = 0.0069）. CONCLUSION： TWAJJ （high dose） treatment partly restored the morphometric and biomechanical remodel- ing of the upper gastrointestinal tract in diabetic rats.展开更多
AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recor...AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recorded by using physiological methods in rats. The expressions of CNP and natriuretic peptide receptor-B (NPR-B) in gastric tissue were examined by using immunohistochemistry techniques in the diabetic rat. RESULTS: At 4 wk after injection of STZ and vehicle, the frequency of spontaneous contraction of gastric smooth muscle was significantly reduced in diabetic rats, and the frequency was decreased from 3.10 ± 0.14 cycle/min in controls to 2.23 ± 0.13 cycle/min (n = 8, P < 0.01). However, the amplitude of spontaneous contraction was not significant different from the normal rat. CNP significantly inhibited spontaneous contraction of gastric smooth muscle in normal and diabetic rats, but the inhibitory effect was significantly potentiated in the diabetic rats. The amplitudes of spontaneous contraction were suppressed by 75.15% ± 0.71% and 58.92% ± 1.32% while the frequencies were decreased by 53.33% ± 2.03% and 26.95% ± 2.82% in diabetic and normal rats, respectively (n = 8, P < 0.01). The expression of CNP in gastric tissue was not changed in diabetic rats, however the expression of NPR-B was significantly increased in diabetic rats, and the staining indexes of NPR-B were 30.67 ± 1.59 and 17.63 ± 1.49 in diabetic and normal rat, respectively (n = 8, P < 0.01).CONCLUSION: The results suggest that CNP induced an inhibitory effect on spontaneous contraction of gastric smooth muscle, potentiated in diabetic rat via up-regulation of the natriuretic peptides-NPR-B-particulate guanylyl cyclase-cyclic GMP signal pathway.展开更多
AIM: To investigate the effect of Bu-Zhong-Yi-Qi-Tang (Decoction for Reinforcing Middle Jiao and Replenishing Qi) on deficiency of N-glycan/nitric oxide (NO) and islet damage induced by injecting two medium doses of s...AIM: To investigate the effect of Bu-Zhong-Yi-Qi-Tang (Decoction for Reinforcing Middle Jiao and Replenishing Qi) on deficiency of N-glycan/nitric oxide (NO) and islet damage induced by injecting two medium doses of streptozotocin (STZ). METHODS: Diabetes was induced by intraperitoneal injection of STZ at 55 mg/kg on day 1 and day 8. Islet damage was evaluated using a scoring system. Nitrite, nitrate, α-mannosidase and amylase activities were measured by colorimetry. N-glycan patterns of amylase were determined with lectin [ConA, pisum sativum agglutinin (PSA), peanut agglutinin (PNA), and lens culinaris agglutinin (LCA)] affinity precipitation method. RESULTS: Severe islet necrosis and mild islet atrophy were observed in diabetic rats. The number and size ofislets, the activities of α-mannosidase, amylase and nitrite were decreased, while the binding of PNA and LCA to amylase was increased. All of which were improved after treatment with Bu-Zhong-Yi-Qi-Tang. Islet damage was significantly correlated with nitrite, nitrate, α-mannosidase, amylase and the binding of LCA, PNA, and PSA to amylase.CONCLUSION: STZ-induced islet damage is related to N-glycan deficiency in proteins by blocking α-mannosidase activity and no deficiency, accumulation of unfolded proteins, and endoplasmic reticulum stress and activation of cellular signals, all of which are improved after treatment with Bu-Zhong-YiQi-Tang.展开更多
Objective： The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection. Methods： Wistar rats were fed with ...Objective： The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection. Methods： Wistar rats were fed with a high-fat diet for 8 weeks followed by a one-time injection of 25 or 35 mg/kg streptozotocin to induce type 2 diabetes. Then the diabetic rats were fed with regular diet/high-fat diet for 4 weeks. Changes in biochemical parameters were monitored during the 4 weeks. Results： All the rats developed more severe dyslipidemia and hepatic dysfunction after streptozotocin injection. The features of 35 mg/kg streptozotocin rats more resembled type 1 diabetes with decreased body weight and blood insulin. Rats with 25 mg/kg streptozotocin followed by normal diet feeding showed normalized blood glucose level and pancreatic structure, indicating that normal diet might help recovery from certain symptoms of type 2 diabetes. In comparison, diabetic rats fed with high-fat diet presented decreased but relatively stable blood glucose level, and this was significantly higher than that of the control group（P〈0.05）. Conclusions： This model easily recovers with normal diet feeding. A high-fat diet is suggested as the background diet in future pharmacological studies using this model.展开更多
Painful diabetic neuropathy(PDN)is a diabetes mellitus complication.Unfortunately,the mechanisms underlying PDN are still poorly understood.Adenosine triphosphate(ATP)-gated P2X7 receptor(P2X7R)plays a pivotal role in...Painful diabetic neuropathy(PDN)is a diabetes mellitus complication.Unfortunately,the mechanisms underlying PDN are still poorly understood.Adenosine triphosphate(ATP)-gated P2X7 receptor(P2X7R)plays a pivotal role in non-diabetic neuropathic pain,but little is known about its effects on streptozotocin(STZ)-induced peripheral neuropathy.Here,we explored whether spinal cord P2X7R was correlated with the generation of mechanical allodynia(MA)in STZ-induced type 1 diabetic neuropathy in mice.MA was assessed by measuring paw withdrawal thresholds and western blotting.Immunohistochemistry was applied to analyze the protein expression levels and localization of P2X7R.STZ-induced mice expressed increased P2X7R in the dorsal horn of the lumbar spinal cord during MA.Mice injected intrathecally with a selective antagonist of P2X7R and P2X7R knockout(KO)mice both presented attenuated progression of MA.Double-immunofluorescent labeling demonstrated that P2X7R-positive cells were mostly co-expressed with Iba1(a microglia marker).Our results suggest that P2X7R plays an important role in the development of MA and could be used as a cellular target for treating PDN.展开更多
文摘The commercially available inbred obesity-prone C57BL/6J （B6） and outbred stock ICR mice （3-week old） purchased from a breeder of Beijing were weaned onto high-fat diet （HFD）, HFD-3% fructose water （HFDF） and standard rodent chow, respectively. After exposure to the diets for six weeks, HFD and HFDF fed mice were injected intraperitoneally with streptozotocin （STZ, 100mg/kg body weight） and kept on the same diet for next four weeks. Body weight was recorded weekly. Non-fasting blood glucose levels of HFD and HFDF fed mice were measured before and after STZ injections. The body weight of HFD-fed and HFDF-fed B6 mice were significantly lower than that of the control, but body weight of HFD-fed and HFDF-fed ICR mice were significantly higher than that of the control. After injection of STZ, blood glucose levels were above the stardardized criterion （11 mmol/L） for the diabetes mouse model in both HFD and HFDF fed ICR mice, but reverse in B6 mice. The type 2 diabetes model was generated successfully in ICR but not in B6 mice, regardless of whether fructose was supplied. The current results indicated that ICR mouse is still a useful and economical strain for HFD-induced/STZ-treated type 2 diabetes model, and that some variation may occur in the genetic composition among B6 mice bred by different breeders.
基金Supported by National Natural Science Foundation of China,No. 81173259/H2708
文摘AIM： To investigate the effect of Tangweian Jianji （TWAJJ） on the biomechanical and morphometrical remodeling of the upper gastrointestinal tract in diabetic rats. METHODS： Diabetes was induced in 27 rats by in- jecting streptozotocin （40 mg/kg body weight）, the animals were then divided into three groups （n = 9 in each group）, i.e., diabetic control （DM）; high dose （10 g/kg, T1） and low dose （5 g/kg, T2）. Another 10 rats acted as normal controls （Control）. TWAJJ was admin- istered by gavage once daily. Blood glucose and serum insulin levels were measured. Circumferential length, wall thickness and opening angle were measured from esophageal, duodenal, jejunal and ileal ring segments. The residual strain was calculated from the morpho- metric data. Step-wise distension was carried out on esophageal and jejunal segments. The obtained data on the length, diameter and pressure changes were then used to calculate the circumferential and longitu- dinal stresses and strains. Real-time reverse transcrip- tion polymerase chain reaction was used to detect the receptor of advanced glycation end-products （RAGE） mRNA level in jejunal tissues. RESULTS： At the end of the experiment, the blood glucose level was significantly higher and the serum insulin level was significantly lower in DM, T1 and T2 groups than in the control group （Glucose： 30.23 ± 0.41 mmol/L, 27.48 ± 0.27 mmol/L and 27.84 ± 0.29 mmol/ L vs 5.05 ± 0.04 mmol/L, P = 1.65 x 10-16, P = 5.89 x 1019 and P = 1.63 x 10-Is, respectively; Insulin： 1.47 ± 0.32 °tg/L, 2.66 ± 0.44 pg/L, 2.03 ± 0.29 pg/L and 4.17 ± 0.54 pg/L, P = 0.0001, P = 0.029 and P = 0.025, re- spectively）. However, these levels did not differ among the DM, T1 and T2 groups. The wet weight per unit length, wall thickness and opening angle of esophageal and intestinal segments in the DM group were signifi- cantly higher than those in the control group （from P = 0.009 to P = 0.004）. These parameters in the T1 group were significantly lower than those in the DM group （wet weight, duodenum： 0.147 ± 0.003 g/cm vs 0.158 ± 0.001 g/cm, P = 0.047; jejunum, 0.127 ± 0.003 g/cm vs 0.151：1：0.002 g/cm, P = 0.017; ileum, 0.127 ± 0.004 g/cm vs 0.139 ± 0.003 g/cm, P = 0.046; wall thickness, esophagus： 0.84±0.03 mm vs 0.94 ± 0.02 ram, P = 0.014; duodenum： 1.27 ± 0.06 mm vs 1.39 ± 0.05 ram, P = 0.031; jejunum： 1.19 ± 0.07 mm vs 1.34 ± 0.04 mm, P = 0.047; ileum： 1.09 ± 0.04 mm vs 1.15 ± 0.03 mm, P = 0.049; opening angle, esophagus： 112.2 ± 13.2° vs 134.7 ± 14.7°, P = 0.027; duodenum： 105.9 ± 12.3° vs 123.1 ± 13.1°, P = 0.046; jejunum： 90.1 ± 15.4° vs 115.5 ± 13.3°, P = 0.044; ileum： 112.9 ± 13.4° vs 136.1 ± 17.1°, P = 0.035）. In the esophageal and jejunal segments, the inner residual stain was significantly smaller and the outer residual strain was larger in the DN group than in the control group （P = 0.022 and P = 0.035）. T1 treatment significantly restored this biomechanical alteration （P = 0.011 and P = 0.019）, but T2 treatment did not. Fur- thermore, the circumferential and longitudinal stiffness of the esophageal and jejunal wall increased in the DM group compared with those in the control group. T1, but not T2 treatment, significantly decreased the cir- cumferential wall stiffness in the jejunal segment （P = 0.012） and longitudinal wall stiffness in the esophageal segment （P = 0.023）. The mRNA level of RAGE was significantly decreased in the T1 group compared to that in the DN group （P = 0.0069）. CONCLUSION： TWAJJ （high dose） treatment partly restored the morphometric and biomechanical remodel- ing of the upper gastrointestinal tract in diabetic rats.
基金Supported by The National Natural Science Foundation of China, No. 30760068
文摘AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recorded by using physiological methods in rats. The expressions of CNP and natriuretic peptide receptor-B (NPR-B) in gastric tissue were examined by using immunohistochemistry techniques in the diabetic rat. RESULTS: At 4 wk after injection of STZ and vehicle, the frequency of spontaneous contraction of gastric smooth muscle was significantly reduced in diabetic rats, and the frequency was decreased from 3.10 ± 0.14 cycle/min in controls to 2.23 ± 0.13 cycle/min (n = 8, P < 0.01). However, the amplitude of spontaneous contraction was not significant different from the normal rat. CNP significantly inhibited spontaneous contraction of gastric smooth muscle in normal and diabetic rats, but the inhibitory effect was significantly potentiated in the diabetic rats. The amplitudes of spontaneous contraction were suppressed by 75.15% ± 0.71% and 58.92% ± 1.32% while the frequencies were decreased by 53.33% ± 2.03% and 26.95% ± 2.82% in diabetic and normal rats, respectively (n = 8, P < 0.01). The expression of CNP in gastric tissue was not changed in diabetic rats, however the expression of NPR-B was significantly increased in diabetic rats, and the staining indexes of NPR-B were 30.67 ± 1.59 and 17.63 ± 1.49 in diabetic and normal rat, respectively (n = 8, P < 0.01).CONCLUSION: The results suggest that CNP induced an inhibitory effect on spontaneous contraction of gastric smooth muscle, potentiated in diabetic rat via up-regulation of the natriuretic peptides-NPR-B-particulate guanylyl cyclase-cyclic GMP signal pathway.
基金Supported by The Project of Guangdong Science and Technology
文摘AIM: To investigate the effect of Bu-Zhong-Yi-Qi-Tang (Decoction for Reinforcing Middle Jiao and Replenishing Qi) on deficiency of N-glycan/nitric oxide (NO) and islet damage induced by injecting two medium doses of streptozotocin (STZ). METHODS: Diabetes was induced by intraperitoneal injection of STZ at 55 mg/kg on day 1 and day 8. Islet damage was evaluated using a scoring system. Nitrite, nitrate, α-mannosidase and amylase activities were measured by colorimetry. N-glycan patterns of amylase were determined with lectin [ConA, pisum sativum agglutinin (PSA), peanut agglutinin (PNA), and lens culinaris agglutinin (LCA)] affinity precipitation method. RESULTS: Severe islet necrosis and mild islet atrophy were observed in diabetic rats. The number and size ofislets, the activities of α-mannosidase, amylase and nitrite were decreased, while the binding of PNA and LCA to amylase was increased. All of which were improved after treatment with Bu-Zhong-Yi-Qi-Tang. Islet damage was significantly correlated with nitrite, nitrate, α-mannosidase, amylase and the binding of LCA, PNA, and PSA to amylase.CONCLUSION: STZ-induced islet damage is related to N-glycan deficiency in proteins by blocking α-mannosidase activity and no deficiency, accumulation of unfolded proteins, and endoplasmic reticulum stress and activation of cellular signals, all of which are improved after treatment with Bu-Zhong-YiQi-Tang.
文摘Objective： The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection. Methods： Wistar rats were fed with a high-fat diet for 8 weeks followed by a one-time injection of 25 or 35 mg/kg streptozotocin to induce type 2 diabetes. Then the diabetic rats were fed with regular diet/high-fat diet for 4 weeks. Changes in biochemical parameters were monitored during the 4 weeks. Results： All the rats developed more severe dyslipidemia and hepatic dysfunction after streptozotocin injection. The features of 35 mg/kg streptozotocin rats more resembled type 1 diabetes with decreased body weight and blood insulin. Rats with 25 mg/kg streptozotocin followed by normal diet feeding showed normalized blood glucose level and pancreatic structure, indicating that normal diet might help recovery from certain symptoms of type 2 diabetes. In comparison, diabetic rats fed with high-fat diet presented decreased but relatively stable blood glucose level, and this was significantly higher than that of the control group（P〈0.05）. Conclusions： This model easily recovers with normal diet feeding. A high-fat diet is suggested as the background diet in future pharmacological studies using this model.
基金Project supported by the National Natural Science Foundation of China(Nos.81771208 and 81971043)the Health and Family Planning Commission of Wuxi(No.YGZXM1406)+3 种基金the Wuxi Municipal Bureau on Science and Technology(No.CSE31N1614)the Fundamental Research Fund of Wuxi People’s Hospital(No.RKA201720)the Technology for Social Development Project of Kunshan(No.KS1539)China.
文摘Painful diabetic neuropathy(PDN)is a diabetes mellitus complication.Unfortunately,the mechanisms underlying PDN are still poorly understood.Adenosine triphosphate(ATP)-gated P2X7 receptor(P2X7R)plays a pivotal role in non-diabetic neuropathic pain,but little is known about its effects on streptozotocin(STZ)-induced peripheral neuropathy.Here,we explored whether spinal cord P2X7R was correlated with the generation of mechanical allodynia(MA)in STZ-induced type 1 diabetic neuropathy in mice.MA was assessed by measuring paw withdrawal thresholds and western blotting.Immunohistochemistry was applied to analyze the protein expression levels and localization of P2X7R.STZ-induced mice expressed increased P2X7R in the dorsal horn of the lumbar spinal cord during MA.Mice injected intrathecally with a selective antagonist of P2X7R and P2X7R knockout(KO)mice both presented attenuated progression of MA.Double-immunofluorescent labeling demonstrated that P2X7R-positive cells were mostly co-expressed with Iba1(a microglia marker).Our results suggest that P2X7R plays an important role in the development of MA and could be used as a cellular target for treating PDN.
