Effect of obesity and overweight on cyclosporine blood levels and renal functions in renal adolescent recipients

INTRODUCTION: The impact of obesity, a frequent problem after renal transplantation, which has been associated with poor graft and patient survival, was evaluated on renal function and cyclosporine (CsA) blood levels. PATIENTS: We retrospectively evaluated the data of adolescent renal recipients between 1994 and 2004. Patients with serum creatinine > or = 2.5 mg/dL were excluded. We grouped the data with regard to the body mass index (BMI) percentiles as group I (BMI > 95th), group II (BMI < 95th), group III (BMI > 85th), group IV (BMI < 85th). We compared the clinical and laboratory findings between groups I and II and between groups III and IV. RESULTS: We evaluated 778 visits of 27 patients (M/F: 19/8). There were 30 visits in the obesity period (group I) and 72 visits after the overweight periods were added (group III). Serum creatinine levels were significantly higher and glomerular filtration rate levels significantly lower among obese and/or overweight than lean periods (P < .05). Proteinuria levels were similar in groups I and II, but significantly higher in group III than group IV (P = .356 and .000, respectively). CsA(mg/bw), CsA(mg/bmi), and CsA(mg/bsa) levels were significantly lower in group I than group II and in group III than group IV (P < .05), while C0 and C2 levels were similar (P > .05). CONCLUSION: Weight gain is associated with worse renal functions but not greater proteinuria in our patients. Smaller CsA doses were sufficient to maintain C0 and C2 levels similar to the lean patients, results that were parallel to those of adult renal recipients.     

Effect of ranitidine on bupivacaine disposition

This study was undertaken to determine the effect, if any, of ranitidine on bupivacaine disposition in 28 women undergoing cesarean section. Before epidural anesthesia, ranitidine (50 mg IM) or sodium citrate (30 mL orally) was administered to groups of 14 parturients each. Ranitidine was administered 2 h before epidural anesthesia and sodium citrate was administered 10 min before the epidural. Maternal plasma samples were collected after epidural anesthesia with bupivacaine. A total of 15 maternal plasma samples were taken from the time of administration of epidural anesthesia up to 180 min. Postpartum plasma and urine samples were also collected from both mothers and neonates. Plasma samples were collected up to 48 h postpartum at intervals of 12, 24, and 48 h. Urine samples were collected at six 6-h intervals up to 36 h postpartum. A two-way analysis of variance with repeated measures demonstrated that there was no significant difference in bupivacaine levels between the maternal plasma curves of the ranitidine and the control groups. At the time of delivery, plasma levels of bupivacaine and its N-dealkylated metabolite PPX (2,6-pipecolylxylidine) were no different in the mothers or neonates of either group. There was no significant difference in plasma protein binding of bupivacaine in the presence of ranitidine. The excretion rates of bupivacaine and PPX were not measurably influenced by ranitidine. The amount of bupivacaine excreted, the amount of metabolite excreted, and the percentage of drug excreted as metabolite in maternal urine were not significantly different. These data indicate that there is no measurable effect of ranitidine on the disposition of bupivacaine in parturients.     

Effect of cyclosporine on host defence

To discover whether cyclosporine administered daily in therapeutic equivalent doses for 3 consecutive weeks suppressed host defence, the authors measured the delayed-type hypersensitivity (DTH) skin response to keyhole-limpet hemocyanin (KLH) in rats. Twenty, male, Sprague-Dawley rats were sensitized to KLH and reactivity was confirmed 14 days later. Following sensitization, cyclosporine (20 mg/kg orally) was administered daily for 21 days to 10 rats. The other 10 (control group) received equivalent volumes of diluent (polysorbate 80 and ethanol). There was no difference in the DTH response between the cyclosporine and control groups for 5 weeks following treatment. Larger doses of cyclosporine (100 mg/kg) given intraperitoneally 30 minutes before and 6 hours after skin testing, suppressed the DTH response (7.2 mm to 2.4 mm) but resulted in a high mortality (eight of nine rats) at 48 hours. Delayed-type hypersensitivity was also suppressed in the control group but to a lesser extent and with no deaths (6.4 to 3.9 mm, p less than 0.05). Cyclosporine, in therapeutic equivalent doses, does not suppress the nonspecific immune component of host defence as reflected by the DTH skin response in previously sensitized animals. This may partially explain the lower frequency of septic morbidity and mortality in cyclosporine-treated transplant patients, compared with those receiving conventional therapy.     

Effect of cyclosporine on adriamycin induced nephritis

The effects of cyclosporine A (CSA) administration, started as early as renal lesion is induced, on the development of Adriamycin-induced nephropathy were assessed by comparing the time course of this nephropathy in rats receiving CSA with that in non-treated animals (group ADR) over 16 weeks. Throughout the experiment, no significant difference in proteinuria was observed between the groups. At the end of the experiment, there was no significant difference between the groups regarding the frequency of glomerular lesion (Group AADR: Md = 23%, P25 = 15%, P75 = 75%; Group ADR-CSA: Md = 48%, P25 = 11%, P75 = 70%); tubulointerstitial lesion index (Group ADR: Md = 1.5, P25 = 1.0, P75 = 2.5); glomerulosclerosis area (Group ADR = 18.2 +/- 4.2%; Group ADR-CSA = 13.2 +/- 1.4%); and, interstitial fibrosis area (Group ADR+V: 1.75 +/- 0.10%; group ADR-CSA: 1.34 +/- 0.09%). In conclusion, CSA, when administered since nephropathy induction does not change the course of the disease.     

Effect of cyclosporine on established islet autografts

Cyclosporine (CyA) is toxic to the function of isolated islets and this toxicity may, in part, explain the failure of islet allografts as well as autografts with CyA immunosuppression. Not only do canine allografts fail despite CyA immunosuppression, but control autografts given CyA from the day prior to transplantation have a very high failure rate. In this study, we investigated CyA effects on established islet autografts. Twenty mongrel dogs underwent total pancreatectomy and successful intrasplenic islet autotransplantation. Ten served as control autografts (Group 1); five were started on oral CyA on the 5th postoperative day (Group 2) and 5 dogs were given CyA from the 10th day after grafting (Group 3). Intravenous glucose tolerance tests were performed before operation, before starting CyA and after 3 weeks. Plasma insulin was determined by radioimmunoassay. Control dogs remained normoglycemic throughout the study as did Group 3 animals. In Group 2, 2 of 5 dogs failed, both on the 4th day of CyA, while the other 3 were normoglycemic throughout the study. No significant difference was shown among the K values, fasting blood glucose and peak plasma insulin values following IVGTT before and after treatment with CyA. CyA begun the day before autografting gravely compromises graft success. However, after the graft is well established, an adverse effect of CyA on islet cell function is not evident.     

Effect of cyclosporine on renal ischemic injury

To determine whether cyclosporine exacerbated renal ischemic injury and whether or not the timing of cyclosporine administration was important, rats were subjected to 30 or 45 min of ischemia. Cyclosporine was administered either before or after the renal ischemic insult. A single intravenous dose of cyclosporine, 20 mg/kg, before ischemia had no additional deleterious effect on inulin clearance compared with rats subjected to ischemia alone. In contrast, a significant exacerbation of the diminished glomerular filtration rate (GFR) produced by ischemia occurred when a low dose of cyclosporine (5 mg/kg) was given after ischemia. With 30 min of ischemia, GFR was 160 +/- 40 microliter/min/100 g in rats receiving cyclosporine (5 mg/kg) after ischemia compared with 280 +/- 40 microliter/min/100 g in rats subjected to ischemia alone. After 45 min of ischemia, cyclosporine (5 mg/kg) markedly reduced GFR to 20 +/- 10 microliter/min/100 g, a value significantly lower (P less than 0.05) than that observed in rats subjected to 45 min of ischemia alone (290 +/- 100 microliter/min/100 g). Plasma potassium concentrations tended to be higher and urinary potassium and sodium excretion lower in rats subjected to ischemia plus cyclosporine compared with ischemia alone. These findings indicate that even a single low dose of parenteral cyclosporine can exacerbate renal ischemic injury if given immediately after the ischemic insult. This interaction may contribute to the acute renal failure observed with cyclosporine use. In contrast, the kidney appears to be relatively resistant to a single dose of cyclosporine injury when the drug is administered prior to ischemia. These data suggest that the administration of parenteral cyclosporine immediately after transplantation could have deleterious effects and should probably be avoided.     

Effect of cyclosporine on bile secretion in rats

Short-term effects of cyclosporine were studied in the isolated perfused rat liver model. Bile flow was inhibited by cyclosporine in 2 mg/kg and 20 mg/kg doses but not by a 0.2 mg/kg dose. Cholestasis was accompanied by a decrease in bile acid secretion, indicating an inhibitory effect on the bile acid-dependent fraction of bile flow. Perfusate bilirubin levels increased threefold in rat livers given 20 mg/kg of cyclosporine, but did not change in control animals. Alkaline phosphatase and transaminase levels did not differ from those of control animals. The isolated perfused rat liver was able to excrete cyclosporine, as demonstrated by a continual decrease in perfusate cyclosporine levels. No light microscopic evidence of cholestasis or hepatocellular damage was demonstrated on histologic staining. Our model appears to be a good one for the study of altered hepatic physiologic characteristics caused by administration of cyclosporine.     

Effect of cyclosporine on human sperm motility in vitro

Cyclosporine affects motility and viability of human sperm when incubated together in vitro. Sperm motility was almost reduced to nil following 10 min of incubation with cyclosporine at a concentration of 1 mg/mL. However, 200 micrograms/mL of the drug has no effect on motility and viability when tested for up to 60 min under standard laboratory conditions. Cyclosporine effect on sperm was both dose and time dependent. Sperm sensitivity and susceptibility to cyclosporine even to lower doses increased significantly following withdrawal of bovine serum albumin from the incubating medium. Compared to untreated controls, lactate dehydrogenase was estimated higher by more than 2 to 4 times in the sperm-free incubating media, suggesting an altered membrane porosity in the affected spermatozoa.     

Effect of obesity on esophageal transit

Esophageal transit time as measured by radionuclide scintigraphy using a swallowed technetium sulfur colloid bolus was measured in obese patients with gastroesophageal reflux, lean patients with reflux, and lean volunteers without reflux. The esophageal transit time was significantly prolonged in the obese group compared with both lean groups (p less than 0.001). Esophageal manometric measurement also confirmed that obese patients have an elevated gastroesophageal pressure gradient, presumably caused by increased intraabdominal pressure resulting from the mechanical burden of excess fat. The esophageal transit time is significantly related to the gastroesophageal pressure gradient. This finding, coupled with those in previous manometric investigations showing that esophageal muscle has a decreased maximum velocity with increasing afterload, explains in part why obese patients have delayed esophageal transit time. Therapy for reflux in obese patients should be aimed at improving esophageal transit.     

Effect of long-term cyclosporine administration on muscle flap hemodynamics

Long-term use of cyclosporine A (CsA) is associated with deleterious effects such as nephrotoxicity and hypertension as a result of its toxicity on microvasculature. These effects raise the possibility that long-term CsA use harms the microvasculature of the skeletal muscle tissue. An experimental study was conducted to investigate the effect of chronic systemic cyclosporine administration on the microvasculature of the cremaster flap model in the rat. Thirty male Sprague-Dawley rats were divided into five groups of 6 animals each. The control group received no treatment. The four CsA treatment groups received a daily subcutaneous injection of 2 mg per kilogram, 4 mg per kilogram, 8 mg per kilogram, and 16 mg per kilogram of cyclosporine for 6 weeks before surgery. The effect of long-term CsA administration on cremaster flap microcirculation was evaluated in vivo using an intravital microscopy system. Hemodynamic parameters of the cremaster muscle flap such as vessel diameter, red blood cell velocity, capillary density, leukocyte-endothelial interaction, and microvascular permeability were measured. There was no significant (p > 0.05) difference in vessel diameter in all groups. There was a significant increase in the number of adherent leukocytes in the 8-mg and 16-mg CsA group compared with the control (12 +/- 4.8 leukocytes per 100 microm and 12 +/- 4.5 leukocytes per 100 microm vs. 6 +/- 4.3 leukocytes per 100 microm; p < 0.05). Microvascular permeability indices increased significantly at 0 and 30 minutes after fluorescent isothiocyanate-albumin injection in the 8-mg and 16-mg CsA groups compared with the control (0 minutes: 0.6 +/- 0.2% and 0.5 +/- 0.1% vs. 0.4 +/- 0.05%; 30 minutes: 0.8 +/- 0.2% and 0.7 +/- 0.1% vs. 0.5 +/- 0.04%; p < 0.05). Histologically, the cremaster muscle flaps in all cyclosporine groups showed evidence of interstitial inflammation and venous vasculitis. In the 8-mg and 16-mg CsA groups there was also focal muscle injury. The toxic effect of CsA on the microvascular tree of a muscle flap was demonstrated by the increased permeability index in vivo, and the moderate venulitis and focal muscle injury histologically. Systemic CsA administration seems to have minimal impact on the viability of the muscle flaps, which was confirmed by preserved capillary function and muscle flap perfusion. These data suggest that there is a minimal risk in undertaking a pedicled muscle flap transfer procedure using a CsA immunosuppressive protocol.     

Effect of cyclosporine on secondary cytotoxic T lymphocyte responses

Cyclosporine, a potent immunosuppressive agent, inhibits the development of the cytotoxic response in a secondary mixed lymphocyte reaction (MLR) in a dose-dependent manner. Exogenous lymphokines can partially overcome this inhibition. We present evidence that the CsA-resistant cells detected in these responses represent an activated population of memory CTL precursors that require only lymphokines for clonal growth and that kill targets of the original stimulator type only. Recombinant IL-4, when used at high concentrations, can support the generation of CTL in the presence of CsA during a secondary MLR response. The magnitude of the cytotoxic response though is far below the maximal levels achieved either by saturating quantities of rIL-2 or a combination of subsaturable quantities of rIL-2 and rIL-4.     

Effect of cyclosporine on steroidogenesis in rat Leydig cells

Cyclosporine induces hypoandrogenism in adult male rats. In order to assess whether this effect of CsA may be due to a direct inhibitory effect on Leydig cell function, CsA (0, 50, 500, and 5000 ng/ml) was added to a collagenase-dispersed mixed Leydig cell preparation and incubated with and without hCG (0, 0.1, 0.3, 1.0, 3.0, and 10.0 ng/ml). Testosterone (T) production, mitochondrial cholesterol side chain cleavage (CSCC) and microsomal 17,20-desmolase enzyme activities in Leydig cells were determined after 3 hr of incubation. In the absence of CsA, stimulation of T production was maximal (about 16-fold) with 1.0 ng/ml hCG. With 50 and 500 ng/ml CsA there were no changes in either the hCG-stimulated T levels or the two enzymatic activities. However, 5000 ng/ml CsA significantly (P less than 0.05) reduced the hCG (1 ng/ml)-stimulated T levels, CSCC and 17,20-desmolase activities. The high dosage of CsA (5000 ng/ml) also caused a significant decrease in cell viability (P less than 0.05) during the incubation period. These effects of CsA were not due to cremophor EL, the CsA vehicle. This in vitro data indicate that high dosages of CsA (greater than or equal to 5000 ng/ml) appear to have a cytotoxic effect on rat Leydig cells that results in a decrease in T production. However, lower doses of CsA (less than 500 ng/ml) do not have any direct inhibitory effect on the rat Leydig cells, suggesting that the hypoandrogenic effect of in vivo CsA in rats is not due to any direct effect on the testis.     

Effect of cyclosporine on apoptosis in bronchial epithelial cells

Objectives

Among airway complications, posttransplantation infections are related to impaired mucociliary clearance, which may represent a toxicity of cyclosporine (CsA), a potent, widely used immunosuppressive drug after organ transplantations. Since several recent studies have demonstrated CsA treatment to directly induce apoptosis in several cell types, we investigated its effects on airway cells using the human bronchial epithelial cell line BEAS-2B.

Methods

Proliferation was measured by using a Cell Counting Assay Kit by exposing cells to CsA (0, 10, 30, 50, or 100 μg/mL). Apoptotic cells were identified using fluorescence microscopy after 4′, 6-diamidino-2-phenylidole (DAPI) staining. Western blot analysis was performed to evaluate the contents of poly(adenosine diphosphate-ribose) polymerase (PARP), p27, Bcl-2, and caspase-3.

Results

Cell viability decreased dependent on the CsA concentration: 100.00 ± 0.01% with 0 μg CsA as control; 98.65 ± 0.02% with 10 μg (P < .05 vs control); 95.41 ± 0.05% with 30 μg (P < .05 vs control); 38.84 ± 0.04% (P < .001 vs control) with 50 μg; and 15.28 ± 0.05% with 100 μg (P < .001 vs control). Apoptotic cells detected with DAPI showed chromatin condensation and nuclear fragmentation. CsA induced p27 and p53, as well as degradation of 116-kd PARP into an 89-kd fragment.

Conclusion

CsA induced apoptosis in human bronchial epithelial cells.     

精氨酸对环孢素A所致睾丸毒性的影响

目的 研究精氨酸对环孢素A（CsA)所致睾丸毒性的影响。方法 将60只大鼠分为3组。N组：正常对照组；A组：单独使用CsA组；B组：使用CsA 精氨酸组。A、B组大鼠每天腹腔注射给药，连续3周后取血及睾丸组织测定CsA浓度，用流式细胞仪测定睾丸细胞的凋亡数量，按抗精子发生效应积分评定法作生精功能的评价，测定曲细精管直径及作病理学检查。结果 CsA血药浓度，B组显著高于A组（P＜0．05）；睾丸组织的CsA浓度，A、B两组差异无显著性。A、B两组大鼠睾丸中精子发生明显障碍，但B组比A组的精子发生障碍要轻（P＜0．05），曲细精管的直径，A、B两组显著小于N组（P＜0．05），但B组大于A组（P＜0．01）。睾丸细胞凋亡率A组显著高于B组和N组（P＜0．001），而B、N两组间差异无显著性。结论 CsA影响睾丸的生精功能并诱导细胞凋亡；精氨酸能明显提高血中CsA的浓度，降低CsA对睾丸的毒性作用。     

Effect of cyclosporine on expression of MIC in human hepatocytes

OBJECTIVES: The human major histocompatibility complex class I chain-related antigen A, B (MICA, B) are believed to be "cell stress sensors," which encode stress-inducible surface proteins that bind to NKG2D, an activating receptor of NK, alpha beta and gamma delta T cells. While cyclosporine (CsA) has improved patient and graft survival rates following solid organ transplantation, its clinical use is often limited by acute and chronic toxicity. Besides ischemia-reperfusion injury, which could up-regulate the expression of MIC, the toxicity of CsA may also be another violent stress factor. The purpose of this study was to investigate whether CsA can affect the expression of MIC. METHODS: Various doses of CsA (5 or 20 microg/mL) was added to cultured human hepatocytes for 1, 3, 5, 8, or 24 hours. The expression of MIC was measured by immunofluorescence using a laser scanning confocal microscope. RESULTS: CsA (5 or 20 microg/mL) upregulated MIC protein expression in hepatocytes at 1 hour, peaking at 3 hours, and persisting until 5 hours (P < .05), returning to normal levels after 8 to 24 hours (P > .05). CONCLUSION: This study reported that CsA up-regulated MIC expression on human hepatocytes. MIC, as a "cellular stress biomarker," may play a significant role in activating NK, T, and B lymphocyte responses associated with transplantation. This study suggested that immunosuppressants produce deterioration in organ function in transplantation.