Toshihisa Ogawa, A. K. Nussler, Eda Tuzuner, Peter Neuhaus, Michio Kaminishi, Yoshikazu Mimura, Hans G. Beger
We examined the contribution of nitric oxide (NO) to the effect of ischemic preconditioning (IP) on renal function and the hemodynamics in ischemia-reperfusion (I/R) mediated kidney injury. IP was performed by using 4 minutes of ischemia followed by a 30-minute reperfusion interval. I/R treatment consisted of a 30-minute ischemia and 60-minute reperfusion interval. We measured the glomerular filtration rate (GFR), the fractional excretion of sodium (FE(Na)), and the renal blood flow (RBF) in IP+I/R and I/R kidneys. Rats were pretreated with NaCl, N(G)-nitro-L-arginine methyl ester (L-NAME), or L-arginine. We found that IP significantly improved GFR and FE(Na) as compared with I/R treatment; however, this effect was completely abolished by L-NAME injection and enhanced by L-arginine treatment. L-NAME treatment significantly diminished RBF but did not alter nitrite/nitrate excretion. Furthermore, we found that IP alone does not lead to inducible NO synthase protein expression whereas I/R or IP+I/R treatment clearly did. Moreover, we observed an increased heme oxygenase-1 expression in IP+I/R kidneys as compared with I/R treated ones. Our results clearly showed that IP pretreatment protects kidneys from I/R mediated tissue injury and that these effects were partially mediated by NO.
我们研究了一氧化氮(NO)在缺血预处理(IP)对肾功能的影响以及缺血再灌注(I/R)介导的肾损伤中的血流动力学。缺血4分钟，再灌注间隔30分钟。I/R治疗包括30分钟缺血和60分钟再灌注间隔。我们测量了IP+I/R和I/R肾脏的肾小球滤过率(GFR)、钠的分数排泄(FE(Na))和肾血流量(RBF)。大鼠分别用NaCl、N(G)-硝基- l -精氨酸甲酯(L-NAME)或l -精氨酸预处理。我们发现，与I/R处理相比，IP显著改善了GFR和FE(Na);然而，L-NAME注射完全消除了这种作用，l -精氨酸处理增强了这种作用。L-NAME处理显著降低RBF，但没有改变亚硝酸盐/硝酸盐排泄。此外，我们发现单独使用IP不能诱导NO合成酶蛋白的表达，而使用I/R或IP+I/R处理可以明显诱导NO合成酶蛋白表达。此外，我们观察到与I/R处理相比，IP+I/R肾脏中血红素氧化酶-1的表达增加。我们的研究结果清楚地表明，IP预处理可以保护肾脏免受I/R介导的组织损伤，而这些作用部分是由NO介导的。
{"title":"Contribution of nitric oxide to the protective effects of ischemic preconditioning in ischemia-reperfused rat kidneys.","authors":"Toshihisa Ogawa, A. K. Nussler, Eda Tuzuner, Peter Neuhaus, Michio Kaminishi, Yoshikazu Mimura, Hans G. Beger","doi":"10.1067/MLC.2001.115648","DOIUrl":"https://doi.org/10.1067/MLC.2001.115648","url":null,"abstract":"We examined the contribution of nitric oxide (NO) to the effect of ischemic preconditioning (IP) on renal function and the hemodynamics in ischemia-reperfusion (I/R) mediated kidney injury. IP was performed by using 4 minutes of ischemia followed by a 30-minute reperfusion interval. I/R treatment consisted of a 30-minute ischemia and 60-minute reperfusion interval. We measured the glomerular filtration rate (GFR), the fractional excretion of sodium (FE(Na)), and the renal blood flow (RBF) in IP+I/R and I/R kidneys. Rats were pretreated with NaCl, N(G)-nitro-L-arginine methyl ester (L-NAME), or L-arginine. We found that IP significantly improved GFR and FE(Na) as compared with I/R treatment; however, this effect was completely abolished by L-NAME injection and enhanced by L-arginine treatment. L-NAME treatment significantly diminished RBF but did not alter nitrite/nitrate excretion. Furthermore, we found that IP alone does not lead to inducible NO synthase protein expression whereas I/R or IP+I/R treatment clearly did. Moreover, we observed an increased heme oxygenase-1 expression in IP+I/R kidneys as compared with I/R treated ones. Our results clearly showed that IP pretreatment protects kidneys from I/R mediated tissue injury and that these effects were partially mediated by NO.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"18 2 1","pages":"50-8"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83189735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Treatment of rheumatoid arthritis: Tightening the noose.","authors":"H. Krug","doi":"10.1067/MLC.2001.115937","DOIUrl":"https://doi.org/10.1067/MLC.2001.115937","url":null,"abstract":"","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"58 1","pages":"5-7"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86683808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Previous research has suggested that type 1 diabetes mellitus may be due to oxidative stress. The role of oxidative stress in type 2 diabetes is not known. Secoisolariciresinol diglucoside (SDG) antioxidant, obtained from flaxseed, has been reported to prevent type 1 diabetes in a rat model. However, its effectiveness in type 2 diabetes is not known. An investigation was made of the effects of SDG isolated from flaxseed (40 mg/kg body wt, orally in drinking water) on the development of diabetes in Zucker diabetic fatty (ZDF)/Gmi-fa/fa female rats, a model of human type 2 diabetes, to determine whether this type of diabetes is due to oxidative stress and whether SDG could prevent the development of diabetes. A total of 10 Zucker lean control and 26 ZDF rats were used in this study. Incidence of diabetes was 100% in untreated and 20% in SDG-treated ZDF rats by the age of 72 days (P <.01). The rats that did not develop diabetes by 72 days of age in the SDG-treated group developed diabetes later on (age 72 to 99 days) except for 10% of the rats that did not develop diabetes for the duration of the study (101 days of age), suggesting that SDG retarded the development of diabetes. Diabetes was associated with an increase in oxidative stress as suggested by an increase in serum malondialdehyde (P <.01). Also, diabetes was associated with an increase in serum total cholesterol and triglycerides (P <.05) and glycated hemoglobin A(1C) (P <.05). ZDF rats treated with SDG that did not develop diabetes by 70 days of age had no increase in oxidative stress, serum total cholesterol, and glycated hemoglobin. These results suggest that type 2 diabetes is associated with an increase in oxidative stress and that SDG is effective in retarding the development of diabetes.
{"title":"Secoisolariciresinol diglucoside from flaxseed delays the development of type 2 diabetes in Zucker rat.","authors":"K. Prasad","doi":"10.1067/MLC.2001.115717","DOIUrl":"https://doi.org/10.1067/MLC.2001.115717","url":null,"abstract":"Previous research has suggested that type 1 diabetes mellitus may be due to oxidative stress. The role of oxidative stress in type 2 diabetes is not known. Secoisolariciresinol diglucoside (SDG) antioxidant, obtained from flaxseed, has been reported to prevent type 1 diabetes in a rat model. However, its effectiveness in type 2 diabetes is not known. An investigation was made of the effects of SDG isolated from flaxseed (40 mg/kg body wt, orally in drinking water) on the development of diabetes in Zucker diabetic fatty (ZDF)/Gmi-fa/fa female rats, a model of human type 2 diabetes, to determine whether this type of diabetes is due to oxidative stress and whether SDG could prevent the development of diabetes. A total of 10 Zucker lean control and 26 ZDF rats were used in this study. Incidence of diabetes was 100% in untreated and 20% in SDG-treated ZDF rats by the age of 72 days (P <.01). The rats that did not develop diabetes by 72 days of age in the SDG-treated group developed diabetes later on (age 72 to 99 days) except for 10% of the rats that did not develop diabetes for the duration of the study (101 days of age), suggesting that SDG retarded the development of diabetes. Diabetes was associated with an increase in oxidative stress as suggested by an increase in serum malondialdehyde (P <.01). Also, diabetes was associated with an increase in serum total cholesterol and triglycerides (P <.05) and glycated hemoglobin A(1C) (P <.05). ZDF rats treated with SDG that did not develop diabetes by 70 days of age had no increase in oxidative stress, serum total cholesterol, and glycated hemoglobin. These results suggest that type 2 diabetes is associated with an increase in oxidative stress and that SDG is effective in retarding the development of diabetes.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"37 1","pages":"32-9"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87697882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Sharma, M. Sharma, S. Vamos, V. Savin, T. Wiegmann
We have documented that both receptors of angiotensin II (ANG II) (AT1 and AT2) are involved in regulation of intracellular signals in glomerular epithelial cells (GECs). We studied the role of these receptors in regulation of intracellular ionized calcium [Ca2(+)]i in GECs. Cells were loaded with Indo-1 (Ca2(+)) and SNARF-1 (pH) fluorescent dyes and then incubated with or without ANG II for 1 hour at 37 degrees C. In some experiments AT(1) and AT(2) receptor blockers (Losartan and PD 12339, respectively) were added. In additional experiments cells were incubated with thapsigargin (Tg) and bradykinin (BK) as well as ANG II. A four-channel fluorescence videomicroscope system was used to measure real-time [Ca2(+) ]i in individual cells. Levels of inositol triphosphate (IP(3)) were measured with radioimmunoassay. An amount of 100 nmol/L of ANG II caused a maximal increase in [Ca2(+)]i in calcium-containing buffer. ANG II had no effect on intracellular pH of GECs. Increase in [Ca2(+)]i by ANG II was prevented by the concurrent use of Losartan and PD 123319. BK caused a transient increase in [Ca2(+)]i, which was significantly decreased by ANG II; concurrent addition of Losartan and PD 123319 prevented ANG II effect. ANG II prevented the accumulation of Ca2(+) in intracellular stores. ANG II caused a significant but transient increase in levels of IP(3). In summary, ANG II increases extracellular/intracellular calcium dependent bidirectional Ca2(+) transport in GECs, inhibits BK induced release of Ca2(+) from IP(3) sensitive stores, and, in addition, reduces refilling of endoplasmic reticulum [Ca2(+)] depleted by repeated BK stimulation. Both receptor subtypes appear to be important in ANG II mediated physiologic responses of GECs and may participate in modulation of glomerular function in vivo.
{"title":"Both subtype 1 and 2 receptors of angiotensin II participate in regulation of intracellular calcium in glomerular epithelial cells.","authors":"R. Sharma, M. Sharma, S. Vamos, V. Savin, T. Wiegmann","doi":"10.1067/MLC.2001.115493","DOIUrl":"https://doi.org/10.1067/MLC.2001.115493","url":null,"abstract":"We have documented that both receptors of angiotensin II (ANG II) (AT1 and AT2) are involved in regulation of intracellular signals in glomerular epithelial cells (GECs). We studied the role of these receptors in regulation of intracellular ionized calcium [Ca2(+)]i in GECs. Cells were loaded with Indo-1 (Ca2(+)) and SNARF-1 (pH) fluorescent dyes and then incubated with or without ANG II for 1 hour at 37 degrees C. In some experiments AT(1) and AT(2) receptor blockers (Losartan and PD 12339, respectively) were added. In additional experiments cells were incubated with thapsigargin (Tg) and bradykinin (BK) as well as ANG II. A four-channel fluorescence videomicroscope system was used to measure real-time [Ca2(+) ]i in individual cells. Levels of inositol triphosphate (IP(3)) were measured with radioimmunoassay. An amount of 100 nmol/L of ANG II caused a maximal increase in [Ca2(+)]i in calcium-containing buffer. ANG II had no effect on intracellular pH of GECs. Increase in [Ca2(+)]i by ANG II was prevented by the concurrent use of Losartan and PD 123319. BK caused a transient increase in [Ca2(+)]i, which was significantly decreased by ANG II; concurrent addition of Losartan and PD 123319 prevented ANG II effect. ANG II prevented the accumulation of Ca2(+) in intracellular stores. ANG II caused a significant but transient increase in levels of IP(3). In summary, ANG II increases extracellular/intracellular calcium dependent bidirectional Ca2(+) transport in GECs, inhibits BK induced release of Ca2(+) from IP(3) sensitive stores, and, in addition, reduces refilling of endoplasmic reticulum [Ca2(+)] depleted by repeated BK stimulation. Both receptor subtypes appear to be important in ANG II mediated physiologic responses of GECs and may participate in modulation of glomerular function in vivo.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"68 1","pages":"40-9"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79636663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chun Chen Yu, Chih-Wei Yang, M. Wu, Yi Ching Ko, Chiung-Tseng Huang, Jenn-Jye Hong, Chiu-Ching Huang
Overexpression of inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of lupus glomerulonephritis. Mycophenolate mofetil (MMF), a novel immunosuppressive agent, is currently used in organ transplantation and under evaluation for treatment of autoimmune disorders. Mycophenolic acid, the active metabolite of MMF, has been shown to suppress cytokine-induced nitric oxide production in vitro. The aim of this study was to evaluate the effect of MMF on the expression of renal cortical iNOS mRNA and protection against glomerulonephritis in MRL/lpr mice. Three-month-old MRL/lpr mice (n = 6) displaying clinical symptoms of glomerulonephritis were treated for 3 months with MMF (90 mg/kg/day) dissolved in a vehicle. Controls were age- and sex-matched mice (n = 6) that received the vehicle alone. By reverse-transcription competitive polymerase chain reaction, we found that the renal cortical iNOS/beta-actin mRNA ratio was reduced by 30.8% (P <.05) in MMF-treated mice. Furthermore, MMF significantly reduced urinary nitrite production and degree of glomerulosclerosis. The glomerular volume was reduced by 17.5% (P <.001). Proteinuria was also significantly reduced in the MMF-treated group. However, by electrophoretic mobility shift assay, the nuclear binding of nuclear factor-kappaB (NF-kappaB) was not affected by MMF treatment. We conclude that in addition to its immunosuppressive action, MMF may reduce renal cortical iNOS mRNA expression and diminish glomerulosclerosis in MRL/lpr mice independent of modulation of the NF-kappaB pathway.
{"title":"Mycophenolate mofetil reduces renal cortical inducible nitric oxide synthase mRNA expression and diminishes glomerulosclerosis in MRL/lpr mice.","authors":"Chun Chen Yu, Chih-Wei Yang, M. Wu, Yi Ching Ko, Chiung-Tseng Huang, Jenn-Jye Hong, Chiu-Ching Huang","doi":"10.1067/MLC.2001.115647","DOIUrl":"https://doi.org/10.1067/MLC.2001.115647","url":null,"abstract":"Overexpression of inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of lupus glomerulonephritis. Mycophenolate mofetil (MMF), a novel immunosuppressive agent, is currently used in organ transplantation and under evaluation for treatment of autoimmune disorders. Mycophenolic acid, the active metabolite of MMF, has been shown to suppress cytokine-induced nitric oxide production in vitro. The aim of this study was to evaluate the effect of MMF on the expression of renal cortical iNOS mRNA and protection against glomerulonephritis in MRL/lpr mice. Three-month-old MRL/lpr mice (n = 6) displaying clinical symptoms of glomerulonephritis were treated for 3 months with MMF (90 mg/kg/day) dissolved in a vehicle. Controls were age- and sex-matched mice (n = 6) that received the vehicle alone. By reverse-transcription competitive polymerase chain reaction, we found that the renal cortical iNOS/beta-actin mRNA ratio was reduced by 30.8% (P <.05) in MMF-treated mice. Furthermore, MMF significantly reduced urinary nitrite production and degree of glomerulosclerosis. The glomerular volume was reduced by 17.5% (P <.001). Proteinuria was also significantly reduced in the MMF-treated group. However, by electrophoretic mobility shift assay, the nuclear binding of nuclear factor-kappaB (NF-kappaB) was not affected by MMF treatment. We conclude that in addition to its immunosuppressive action, MMF may reduce renal cortical iNOS mRNA expression and diminish glomerulosclerosis in MRL/lpr mice independent of modulation of the NF-kappaB pathway.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"47 1","pages":"69-77"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84955632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
VPA-985 is an orally active, competitive vasopressin V(2) receptor antagonist that in normal human beings increases water excretion without affecting solute excretion. Whether solute excretion is affected in patients with hyponatremia resulting from inappropriate secretion of antidiuretic hormone (SIADH) or from cirrhosis treated with VPA-985 is unknown. Six hyponatremic patients with SIADH and 5 hyponatremic patients with cirrhosis with ascitis (CWAs) were treated with 50 or 100 mg VPA-985 twice daily. Evolution of creatinine, urea, uric acid, sodium, potassium, and osmotic clearance were determined. Volume hormones (plasma renin [PR], aldosterone, antidiuretic hormone [ADH], atrial natriuretic factor [ANF]) were also determined before and after treatment. In patients with SIADH, serum sodium concentration (SNa) was generally corrected in 1 day (SNa: 126 +/- 4.5 mmol/L at t = 0 hours and 133 +/- 5.6 mmol/L at t = 24 hours) and associated with a decrease in sodium excretion (from 82 +/- 22 mmol/24 hours to 45 +/- 21 mmol/24 hours; P < 0.05) without modification in potassium excretion. Despite an increase in diuresis (from 0.84 +/- 0.2 ml/min to 1.46 +/- 0.4 ml/min) urea and uric acid clearances decreased. Urine osmolality decreased from 414 +/- 148 mOsm/kg H(2)O to 209 +/- 55 mOsm/kg H(2)O. Volume hormones did not change. In the CWAs the rise of SNa was more progressive (SNa: 126 +/- 2.8 mmol/L at t = H0 to 133 +/- 4.9 mmol/L at t = 48 hours) and parallel to an augmentation in sodium excretion (from 23 +/- 18 mmol/24 hours to 65 6 60 mmol/24 hours the second day of VPA administration). The higher sodium excretion was also connected with a progression in potassium excretion (from 22 6 7 mmol/24 hours to 36 +/- 18 mmol/24 hours). The increase in diuresis under VPA from 0.42 +/- 0.2 mL/min to 1.7 +/- 0.9 mL/min resulted in a higher urea clearance. Urine osmolality decreased from 509 +/- 142 mOsm/kg H(2)O before VPA to 194 +/- 106 mOsm/kg H(2)O after VPA. ADH increased in CWAs treated with VPA, from 1.9 +/- 1.2 pg/mL to 5.3 +/- 2.8 pg/mL (P <.05) while other volume hormones did not change. VPA-985 is a highly effective drug in the short-term management of hyponatremic patients with SIADH or CWAs. SNa correction is associated with urinary sodium retention in SIADH, whereas in CWAs a mild increase in sodium excretion is observed.
{"title":"Difference in solute excretion during correction of hyponatremic patients with cirrhosis or syndrome of inappropriate secretion of antidiuretic hormone by oral vasopressin V2 receptor antagonist VPA-985.","authors":"G. Decaux","doi":"10.1067/MLC.2001.116025","DOIUrl":"https://doi.org/10.1067/MLC.2001.116025","url":null,"abstract":"VPA-985 is an orally active, competitive vasopressin V(2) receptor antagonist that in normal human beings increases water excretion without affecting solute excretion. Whether solute excretion is affected in patients with hyponatremia resulting from inappropriate secretion of antidiuretic hormone (SIADH) or from cirrhosis treated with VPA-985 is unknown. Six hyponatremic patients with SIADH and 5 hyponatremic patients with cirrhosis with ascitis (CWAs) were treated with 50 or 100 mg VPA-985 twice daily. Evolution of creatinine, urea, uric acid, sodium, potassium, and osmotic clearance were determined. Volume hormones (plasma renin [PR], aldosterone, antidiuretic hormone [ADH], atrial natriuretic factor [ANF]) were also determined before and after treatment. In patients with SIADH, serum sodium concentration (SNa) was generally corrected in 1 day (SNa: 126 +/- 4.5 mmol/L at t = 0 hours and 133 +/- 5.6 mmol/L at t = 24 hours) and associated with a decrease in sodium excretion (from 82 +/- 22 mmol/24 hours to 45 +/- 21 mmol/24 hours; P < 0.05) without modification in potassium excretion. Despite an increase in diuresis (from 0.84 +/- 0.2 ml/min to 1.46 +/- 0.4 ml/min) urea and uric acid clearances decreased. Urine osmolality decreased from 414 +/- 148 mOsm/kg H(2)O to 209 +/- 55 mOsm/kg H(2)O. Volume hormones did not change. In the CWAs the rise of SNa was more progressive (SNa: 126 +/- 2.8 mmol/L at t = H0 to 133 +/- 4.9 mmol/L at t = 48 hours) and parallel to an augmentation in sodium excretion (from 23 +/- 18 mmol/24 hours to 65 6 60 mmol/24 hours the second day of VPA administration). The higher sodium excretion was also connected with a progression in potassium excretion (from 22 6 7 mmol/24 hours to 36 +/- 18 mmol/24 hours). The increase in diuresis under VPA from 0.42 +/- 0.2 mL/min to 1.7 +/- 0.9 mL/min resulted in a higher urea clearance. Urine osmolality decreased from 509 +/- 142 mOsm/kg H(2)O before VPA to 194 +/- 106 mOsm/kg H(2)O after VPA. ADH increased in CWAs treated with VPA, from 1.9 +/- 1.2 pg/mL to 5.3 +/- 2.8 pg/mL (P <.05) while other volume hormones did not change. VPA-985 is a highly effective drug in the short-term management of hyponatremic patients with SIADH or CWAs. SNa correction is associated with urinary sodium retention in SIADH, whereas in CWAs a mild increase in sodium excretion is observed.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"144 1","pages":"18-21"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78909083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Urayama, A. Kawakami, T. Nakashima, S. Yamasaki, A. Hida, H. Ida, M. Kamachi, H. Nakamura, T. Origuchi, K. Migita, Y. Kawabe, K. Eguchi
We examined in this study whether the newly developed disease-modifying antirheumatic drug (DMARD) 2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298) augments activation-induced T cell death. Peripheral blood (PB) T cells, isolated from healthy donors, were activated by incubation with interleukin-2 (IL-2) followed by further culture with 12-0-tetradecanoyl phorbol 13-acetate (PMA) and ionomycin in the presence or absence of KE-298. The apoptosis of activated T cells was examined by flow cytometric determination of hypodiploid DNA. Fas expression and caspase-3 activity in activated T cells were also examined by flow cytometry, and expression of Fas ligand (FasL), Bcl-2-related proteins, and X chromosome-linked inhibitor of apoptosis protein (XIAP) was determined by Western blot analysis. Apoptosis was not obvious in resting T cells and was not augmented by KE-298. In contrast, apoptosis was clearly detected in activated T cells (activation-induced T cell death) with the increment of caspase-3 activity, and incubation of these cells with KE-298 further enhanced apoptosis. Treatment of activated T cells with KE-298 increased Bax expression but decreased XIAP expression without affecting the expression of Fas/FasL. Thus caspase-3 activity in activated T cells appeared to be increased by KE-298. Our results suggest that the newly developed DMARD, KE-298, selectively augmented activation-induced T cell death. This finding may contribute to the therapeutic efficacy of KE-298 in rheumatoid arthritis (RA) patients and provide new insight into the pharmacologic action of DMARDs.
{"title":"New disease-modifying antirheumatic drug 2 acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298) selectively augments activation-induced T cell death.","authors":"S. Urayama, A. Kawakami, T. Nakashima, S. Yamasaki, A. Hida, H. Ida, M. Kamachi, H. Nakamura, T. Origuchi, K. Migita, Y. Kawabe, K. Eguchi","doi":"10.1067/MLC.2001.115938","DOIUrl":"https://doi.org/10.1067/MLC.2001.115938","url":null,"abstract":"We examined in this study whether the newly developed disease-modifying antirheumatic drug (DMARD) 2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298) augments activation-induced T cell death. Peripheral blood (PB) T cells, isolated from healthy donors, were activated by incubation with interleukin-2 (IL-2) followed by further culture with 12-0-tetradecanoyl phorbol 13-acetate (PMA) and ionomycin in the presence or absence of KE-298. The apoptosis of activated T cells was examined by flow cytometric determination of hypodiploid DNA. Fas expression and caspase-3 activity in activated T cells were also examined by flow cytometry, and expression of Fas ligand (FasL), Bcl-2-related proteins, and X chromosome-linked inhibitor of apoptosis protein (XIAP) was determined by Western blot analysis. Apoptosis was not obvious in resting T cells and was not augmented by KE-298. In contrast, apoptosis was clearly detected in activated T cells (activation-induced T cell death) with the increment of caspase-3 activity, and incubation of these cells with KE-298 further enhanced apoptosis. Treatment of activated T cells with KE-298 increased Bax expression but decreased XIAP expression without affecting the expression of Fas/FasL. Thus caspase-3 activity in activated T cells appeared to be increased by KE-298. Our results suggest that the newly developed DMARD, KE-298, selectively augmented activation-induced T cell death. This finding may contribute to the therapeutic efficacy of KE-298 in rheumatoid arthritis (RA) patients and provide new insight into the pharmacologic action of DMARDs.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"49 1","pages":"11-7"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91302000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Harenberg, L. Wang, U. Hoffmann, G. Huhle, M. Feuring
Laboratory confirmation of heparin-induced thrombocytopenia (HIT) is limited by assay sensitivity. We investigated whether laboratory confirmation can be improved after antigen clearance by determining free antibody and combining the results of antigenic and biologic assays. Blood samples were collected over 5 to 6 weeks in 14 HIT patients. As an antigenic assay, the fluorescence-linked immunofiltration assay (FLIFA) was performed, and as a biologic assay, the carbon 14-labeled serotonin release assay was performed. At day 1 when heparin was stopped, 11 of 14 patients showed positive results in both assays; thus each assay had a sensitivity of 80%. The 3 patients with negative results seroconverted in one or both assays during the subsequent 7 days. Combining the positive results of the assays increased the sensitivity to 100% at day 7, regardless of whether the antigenic or the biologic assay was performed first. Both assays became negative in all patients within 5 to 6 weeks. The sensitivity of antigen and biologic assays in HIT patients increased to 100% after the time course of the heparin-induced antibody. We assume that in some HIT patients the free antibody can be detected after withdrawal of heparin and after clearance of the platelet-factor 4/heparin complex.
{"title":"Laboratory diagnosis of heparin-induced thrombocytopenia type II after clearance of platelet factor 4/heparin complex.","authors":"J. Harenberg, L. Wang, U. Hoffmann, G. Huhle, M. Feuring","doi":"10.1067/MLC.2001.115099","DOIUrl":"https://doi.org/10.1067/MLC.2001.115099","url":null,"abstract":"Laboratory confirmation of heparin-induced thrombocytopenia (HIT) is limited by assay sensitivity. We investigated whether laboratory confirmation can be improved after antigen clearance by determining free antibody and combining the results of antigenic and biologic assays. Blood samples were collected over 5 to 6 weeks in 14 HIT patients. As an antigenic assay, the fluorescence-linked immunofiltration assay (FLIFA) was performed, and as a biologic assay, the carbon 14-labeled serotonin release assay was performed. At day 1 when heparin was stopped, 11 of 14 patients showed positive results in both assays; thus each assay had a sensitivity of 80%. The 3 patients with negative results seroconverted in one or both assays during the subsequent 7 days. Combining the positive results of the assays increased the sensitivity to 100% at day 7, regardless of whether the antigenic or the biologic assay was performed first. Both assays became negative in all patients within 5 to 6 weeks. The sensitivity of antigen and biologic assays in HIT patients increased to 100% after the time course of the heparin-induced antibody. We assume that in some HIT patients the free antibody can be detected after withdrawal of heparin and after clearance of the platelet-factor 4/heparin complex.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"4 1","pages":"408-13"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89705328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Atochina, J. Beck, S. Scanlon, A. M. Preston, M. Beers
Surfactant proteins SP-A and SP-D, members of the collectin family, have been shown to play a significant role in lung host defense. Both proteins selectively bind Pneumocystis carinii (PC) organisms and modulate the interaction of this pathogen with alveolar macrophages. We hypothesized that the expression and distribution of lung collectins SP-A and SP-D is altered by PC lung infection. PC organisms (2 x 10(5)) were inoculated intratracheally into C.B-17 scid/scid mice that do not require steroids for immunosuppression. Four weeks after inoculation, bronchoalveolar lavage (BAL) fluid was fractionated into three fractions-cell pellet, large aggregate (LA), and small aggregate (SA) surfactant-and each fraction was analyzed for the expression of surfactant components. In uninfected mice, the majority of SP-A (62% +/- 10%) was found in association with lipids in the LA fraction, while 55% +/- 14% of SP-D was distributed in the SA fraction. In contrast, both hydrophobic proteins SP-B and SP-C were associated exclusively with LA. PC infection resulted in major changes in the expression of all surfactant components. Total protein content of LA was unchanged by PC infection (115% +/- 18% of control), whereas SA protein content markedly increased (240% +/- 18% of control level, P <.001). In contrast, the phospholipid content of LA was significantly decreased (53% +/- 5% of control level, P <.001), whereas the SA phospholipid content of infected mice was increased (172% +/- 16% of control level, P <.001). By Western blotting, PC pneumonia (PCP) induced a 3-fold increase in the total alveolar SP-D protein that was reflected mainly in increases in SA SP-D (454% +/- 135% of control, P <.05). The total alveolar SP-A protein content was also increased in PCP because of a large increase in SP-A in SA (720% +/- 115% of control, P <.05); SP-A levels in LA were unchanged. The increases in lung collectin expression were selective, because PCP resulted in the down-regulation of both SP-B and SP-C in LA (5% +/- 2% and 13% +/- 2% of control, respectively, P <.001). We conclude that PCP induces marked elevations in alveolar collectin levels because of increased expression and accumulation of SP-A and SP-D protein in SA surfactant.
{"title":"Pneumocystis carinii pneumonia alters expression and distribution of lung collectins SP-A and SP-D.","authors":"E. Atochina, J. Beck, S. Scanlon, A. M. Preston, M. Beers","doi":"10.1067/MLC.2001.115220","DOIUrl":"https://doi.org/10.1067/MLC.2001.115220","url":null,"abstract":"Surfactant proteins SP-A and SP-D, members of the collectin family, have been shown to play a significant role in lung host defense. Both proteins selectively bind Pneumocystis carinii (PC) organisms and modulate the interaction of this pathogen with alveolar macrophages. We hypothesized that the expression and distribution of lung collectins SP-A and SP-D is altered by PC lung infection. PC organisms (2 x 10(5)) were inoculated intratracheally into C.B-17 scid/scid mice that do not require steroids for immunosuppression. Four weeks after inoculation, bronchoalveolar lavage (BAL) fluid was fractionated into three fractions-cell pellet, large aggregate (LA), and small aggregate (SA) surfactant-and each fraction was analyzed for the expression of surfactant components. In uninfected mice, the majority of SP-A (62% +/- 10%) was found in association with lipids in the LA fraction, while 55% +/- 14% of SP-D was distributed in the SA fraction. In contrast, both hydrophobic proteins SP-B and SP-C were associated exclusively with LA. PC infection resulted in major changes in the expression of all surfactant components. Total protein content of LA was unchanged by PC infection (115% +/- 18% of control), whereas SA protein content markedly increased (240% +/- 18% of control level, P <.001). In contrast, the phospholipid content of LA was significantly decreased (53% +/- 5% of control level, P <.001), whereas the SA phospholipid content of infected mice was increased (172% +/- 16% of control level, P <.001). By Western blotting, PC pneumonia (PCP) induced a 3-fold increase in the total alveolar SP-D protein that was reflected mainly in increases in SA SP-D (454% +/- 135% of control, P <.05). The total alveolar SP-A protein content was also increased in PCP because of a large increase in SP-A in SA (720% +/- 115% of control, P <.05); SP-A levels in LA were unchanged. The increases in lung collectin expression were selective, because PCP resulted in the down-regulation of both SP-B and SP-C in LA (5% +/- 2% and 13% +/- 2% of control, respectively, P <.001). We conclude that PCP induces marked elevations in alveolar collectin levels because of increased expression and accumulation of SP-A and SP-D protein in SA surfactant.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"9 1","pages":"429-39"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85720503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent studies suggest that both oxidized very-low-density lipoprotein (VLDL) and oxidized high-density lipoprotein (HDL) may play a role in the pathogenesis of atherosclerosis. Gemfibrozil is widely used and is reported to decrease VLDL levels and increase HDL levels. The aim of this study was to investigate the effect of gemfibrozil on the chemical composition and oxidative susceptibility of VLDL and HDL and their relationship with atherosclerosis. Twenty patients with hypertriglyceridemia were treated with 300 mg gemfibrozil, 3 times daily, for 12 weeks. Venous blood samples were collected before treatment, at the end of treatment, and 4 weeks after the end of treatment. Gemfibrozil effectively lowered concentrations of plasma lipid, apolipoprotein (apo) B, and apo E. The lipid and protein content of VLDL were also decreased, but not by the same extent. The surface-to-core ratio and apo E/apo B ratio of VLDL particles were increased after gemfibrozil treatment. HDL(2) cholesteryl ester and HDL(3) apo A-II content were also increased. Gemfibrozil treatment lowered levels of lipid peroxides in both VLDL and HDL particles. The susceptibility of VLDL to oxidation was unchanged, whereas maximal peroxide production was decreased. The oxidative susceptibility of both HDL(2) and HDL(3) decreased with gemfibrozil treatment. These results indicate that after gemfibrozil treatment, VLDL and HDL particles in patients with hypertriglyceridemia are less atherogenic, which may explain why gemfibrozil treatment is beneficial in terms of coronary heart disease in hypertriglyceridemia.
{"title":"Effect of gemfibrozil on the composition and oxidation properties of very-low-density lipoprotein and high-density lipoprotein in patients with hypertriglyceridemia.","authors":"H. Hsu, Y. T. Lee, H. Yeh, M. F. Chen","doi":"10.1067/MLC.2001.114991","DOIUrl":"https://doi.org/10.1067/MLC.2001.114991","url":null,"abstract":"Recent studies suggest that both oxidized very-low-density lipoprotein (VLDL) and oxidized high-density lipoprotein (HDL) may play a role in the pathogenesis of atherosclerosis. Gemfibrozil is widely used and is reported to decrease VLDL levels and increase HDL levels. The aim of this study was to investigate the effect of gemfibrozil on the chemical composition and oxidative susceptibility of VLDL and HDL and their relationship with atherosclerosis. Twenty patients with hypertriglyceridemia were treated with 300 mg gemfibrozil, 3 times daily, for 12 weeks. Venous blood samples were collected before treatment, at the end of treatment, and 4 weeks after the end of treatment. Gemfibrozil effectively lowered concentrations of plasma lipid, apolipoprotein (apo) B, and apo E. The lipid and protein content of VLDL were also decreased, but not by the same extent. The surface-to-core ratio and apo E/apo B ratio of VLDL particles were increased after gemfibrozil treatment. HDL(2) cholesteryl ester and HDL(3) apo A-II content were also increased. Gemfibrozil treatment lowered levels of lipid peroxides in both VLDL and HDL particles. The susceptibility of VLDL to oxidation was unchanged, whereas maximal peroxide production was decreased. The oxidative susceptibility of both HDL(2) and HDL(3) decreased with gemfibrozil treatment. These results indicate that after gemfibrozil treatment, VLDL and HDL particles in patients with hypertriglyceridemia are less atherogenic, which may explain why gemfibrozil treatment is beneficial in terms of coronary heart disease in hypertriglyceridemia.","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"1 1","pages":"414-21"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89961063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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