2141. Intermittent dosing of the farnesyl transferase inhibitor tipifarnib (R115777) in advanced malignant solid tumors: a phase I California Cancer Consortium Trial.
作者: Primo N Lara.;Lisa Y Law.;John J Wright.;Paul Frankel.;Przemyslaw Twardowski.;Heinz Josef Lenz.;Derick H M Lau.;Tomoya Kawaguchi.;Paul H Gumerlock.;James H Doroshow.;David R Gandara.
来源: Anticancer Drugs. 2005年16卷3期317-21页
Tipifarnib (R115777) inhibits farnesylation of key proteins that modulate signaling pathways implicated in cell growth and proliferation, including members of the Ras and Rho families. It has broad-spectrum antiproliferative activity in vitro and in vivo. Clinical trials employing a continuous administration schedule have demonstrated dose-limiting neurotoxicity and myelosuppression. Preclinical studies have shown that intermittent oral administration can suppress tumor growth comparable to continuous administration. We conducted a National Cancer Institute-sponsored phase I trial to determine the feasibility of an intermittent dosing schedule of R115777 given orally twice daily on weeks 1 and 3 of a 28-day cycle in patients with malignant solid tumors. Starting dose was 300 mg twice daily (b.i.d.) with escalation by 300 mg b.i.d. increments over six dose levels to a maximum of 1800 mg b.i.d. Dose-limiting toxicity (DLT) was defined as any grade 3 or 4 non-hematologic toxicity, grade 4 thrombocytopenia, grade 4 neutropenia (ANC) with fever (38.3 degrees C or above) or a documented infection. Twenty-one patients with advanced solid tumors, all of whom had prior systemic therapy, were accrued. Grade 3 fatigue was dose limiting for two of three patients at the 900 mg b.i.d. dose level. Although no responses were seen, four of six patients with stable disease remained on study for at least a year (16, 17, 13 and 12 months) before developing progressive disease. Three of these prolonged stable disease patients had non-small cell lung cancer. We conclude that intermittent dosing of R115777 is feasible and tolerable. The recommended phase II dose is 600 mg orally b.i.d. on alternate weeks.
2142. The effects of interferon-beta on interleukin-10 in multiple sclerosis patients.
The incidence of the neuropathological lesions and the severity of the clinical symptoms in multiple sclerosis (MS) are correlated with the amount of the transferred autoreactive T cells. The balance between the T helper 1 (Th1) and T helper 2 (Th2) cytokine phenotypes may affect the activity of the disease in MS patients. Interleukin-10 (IL-10) is a cytokine secreted by Th2 cells. Thus, it has been thought that inducing IL-10 may have therapeutic effects in the treatment of MS patients. In this study, in order determine whether different types of prophylaxis change the secretion of IL-10, we measured the levels of IL-10 in relapsing-remitting type multiple sclerosis (RRMS) patients receiving interferon-beta 1b (IFN-beta 1b) or azathioprine (AZA). Our study consisted of RRMS patients (n=45) and healthy subjects (n=15) as control group. Patients were categorized into three groups as those receiving either IFN-beta 1b or AZA and those not receiving prophylaxis. Each group was compared with the control group. Serum IL-10 levels were determined using ELISA method. IL-10 levels of those receiving IFN-beta 1b were found to be significantly higher than that of other groups. These results support that the ability of inducing anti-inflammatory cytokine IL-10 plays a role in the clinical advantage of IFN-beta 1b in MS treatment.
2143. Combined antioxidant treatment effects on blood oxidative stress after eccentric exercise.
作者: Allan H Goldfarb.;Richard J Bloomer.;Michael J McKenzie.
来源: Med Sci Sports Exerc. 2005年37卷2期234-9页
This study was designed to ascertain the effects of a combination antioxidant therapy on plasma protein carbonyls (PC), malondialdehyde (MDA), and whole blood total (TGSH), oxidized (GSSG), and reduced (GSH) glutathione in non-resistance trained females after eccentric resistance exercise.
2144. TNF-alpha, but not IL-6, stimulates plasminogen activator inhibitor-1 expression in human subcutaneous adipose tissue.
作者: Peter Plomgaard.;Pernille Keller.;Charlotte Keller.;Bente Klarlund Pedersen.
来源: J Appl Physiol (1985). 2005年98卷6期2019-23页
Plasminogen activator inhibitor-1 (PAI-1) is produced by adipose tissue, and elevated PAI-1 levels in plasma are a risk factor in the metabolic syndrome. We investigated the regulatory effects of TNF-alpha and IL-6 on PAI-1 gene induction in human adipose tissue. Twenty healthy men underwent a 3-h infusion of either recombinant human TNF-alpha (n = 8), recombinant human IL-6 (n = 6), or vehicle (n = 6). Biopsies were obtained from the subcutaneous abdominal adipose tissue at preinfusion, at 1, 2, and 3 h during the infusion, and at 2 h after the infusion. The mRNA expression of PAI-1 in the adipose tissue was measured using real-time PCR. The plasma levels of TNF-alpha and IL-6 reached 18 and 99 pg/ml, respectively, during the infusions. During the TNF-alpha infusion, adipose PAI-1 mRNA expression increased 2.5-fold at 1 h, 6-fold at 2 h, 9-fold at 3 h, and declined to 2-fold 2 h after the infusion stopped but did not change during IL-6 infusion and vehicle. These data demonstrate that TNF-alpha rather than IL-6 stimulates an increase in PAI-1 mRNA in the subcutaneous adipose tissue, suggesting that TNF-alpha may be involved in the pathogenesis of related metabolic disorders.
2145. Creatine supplementation lowers brain glutamate levels in Huntington's disease.
作者: Andreas Bender.;Dorothee P Auer.;Thomas Merl.;Ralf Reilmann.;Phillip Saemann.;Alexander Yassouridis.;Julia Bender.;Adolf Weindl.;Matthias Dose.;Thomas Gasser.;Thomas Klopstock.
来源: J Neurol. 2005年252卷1期36-41页
There is evidence from in vitro and animal experiments that oral creatine (Cr) supplementation might prevent or slow down neurodegeneration in Huntington's disease (HD). However, this neuroprotective effect could not be replicated in clinical trials, possibly owing to treatment periods being too short to impact on clinical endpoints. We used proton magnetic resonance spectroscopy ((1)H-MRS) as a surrogate marker to evaluate the effect of Cr supplementation on brain metabolite levels in HD.Twenty patients (age 46+/-7.3 years, mean duration of symptoms 4.0+/-2.1 years, number of CAG repeats 44.5+/-2.7) were included. The primary endpoint was metabolic alteration as measured by (1)H-MRS in the parieto-occipital cortex before (t1) and after 8-10 weeks (t2) of Cr administration. Secondary measures comprised the motor section of the Unified Huntington's Disease Rating Scale and the Mini Mental State Examination. (1)H-MRS showed a 15.6% decrease of unresolved glutamate (Glu)+glutamine (Gln; Glu+Gln=Glx; p<0.001) and a 7.8% decrease of Glu (p<0.027) after Cr treatment. N-acetylaspartate trended to fall (p=0.073) whereas total Cr, choline-containing compounds, glucose, and lactate remained unchanged. There was no effect on clinical rating scales. This cortical Glx and Glu decrease may be explained by Cr enhancing the energy-dependent conversion of Glu to Gln via the Glu-Gln cycle, a pathway known to be impaired in HD. Since Glu-mediated excitotoxicity is presumably pivotal in HD pathogenesis, these results indicate a therapeutic potential of Cr in HD. Thus, longterm clinical trials are warranted.
2146. Polymorphisms in FcgammaRIIIA (CD16) receptor expression are associated with clinical response to rituximab in Waldenström's macroglobulinemia.
作者: Steven P Treon.;Mark Hansen.;Andrew R Branagan.;Sigitas Verselis.;Christos Emmanouilides.;Eva Kimby.;Stanley R Frankel.;Nikolaos Touroutoglou.;Barry Turnbull.;Kenneth C Anderson.;David G Maloney.;Edward A Fox.
来源: J Clin Oncol. 2005年23卷3期474-81页
Rituximab is an important therapeutic for Waldenstrom's macroglobulinemia (WM). Polymorphisms in FcgammaRIIIA (CD16) receptor expression modulate human immunoglobulin G1 binding and antibody-dependent cell-mediated cytotoxicity, and may therefore influence responses to rituximab.
2147. Improved insulin sensitivity and adipose tissue dysregulation after short-term treatment with pioglitazone in non-diabetic, insulin-resistant subjects.
作者: A Hammarstedt.;V Rotter Sopasakis.;S Gogg.;P-A Jansson.;U Smith.
来源: Diabetologia. 2005年48卷1期96-104页
We examined whether short-term treatment with a thiazolidinedione improves insulin sensitivity in non-obese but insulin-resistant subjects and whether this is associated with an improvement in dysregulated adipose tissue (reduced expression of IRS-1, GLUT4, PPARgamma co-activator 1 and markers of terminal differentiation) that we have previously documented to be associated with insulin resistance.
2148. Adipose tissue gene expression in obese subjects during low-fat and high-fat hypocaloric diets.
作者: N Viguerie.;H Vidal.;P Arner.;C Holst.;C Verdich.;S Avizou.;A Astrup.;W H M Saris.;I A Macdonald.;E Klimcakova.;K Clément.;A Martinez.;J Hoffstedt.;T I A Sørensen.;D Langin.; .
来源: Diabetologia. 2005年48卷1期123-31页
Adaptation to energy restriction is associated with changes in gene expression in adipose tissue. However, it is unknown to what extent these changes are dependent on the energy restriction as such or on the macronutrient composition of the diet.
2149. Prospective evaluation of estrogen receptor-beta in predicting response to neoadjuvant antiestrogen therapy in elderly breast cancer patients.
作者: Vera Cappelletti.;Luigi Celio.;Emilio Bajetta.;Arianna Allevi.;Raffaella Longarini.;Patrizia Miodini.;Raffaella Villa.;Alessandra Fabbri.;Luigi Mariani.;Riccardo Giovanazzi.;Emanuele Galante.;Marco Greco.;Maria Grazia Daidone.
来源: Endocr Relat Cancer. 2004年11卷4期761-70页
It has been proposed that knowledge of estrogen receptor beta (ER-beta) expression may refine estrogen receptor alpha (ER-alpha) predictivity of response to endocrine therapy. We challenged this hypothesis in ER-alpha-positive breast cancers subjected to preoperative antiestrogen treatment. Forty-seven elderly (> or =65 years old) women with nonmetastatic, ER-alpha-positive (by immunohistochemistry) primary breast cancers (> 2 cm in diameter) entered a neoadjuvant hormone therapy protocol (60 mg/day toremifene for 3 months). ER-alpha and ER-beta (ERs) mRNA was determined by semiquantitative RT-PCR, before (on core needle biopsy) and after (on surgical specimens) neoadjuvant treatment. Study end points included: (1) relation between treatment response and ER mRNA expression; and (2) changes in ER expression after treatment. The response was clinically assessed as tumor size change at the end of the preoperative treatment. ER mRNA expression was assessable before and after treatment in 38 and 20 cases respectively. ER-beta was co-expressed with ER-alpha at variable levels and significantly correlated only with progesterone receptor (P = 0.0285). Objective clinical response, including patients with minor change (> or =25-<50% tumor shrinkage after treatment), was documented in 68.4% of cases and was independent of ER-beta levels or changes. ER-alpha levels were higher in tumors from patients in complete remission than in those from women achieving partial response or minor change compared with non-responsive patients (median expression values: 801 versus 516 versus 320 arbitrary units) and were consistently down-regulated by preoperative treatment. We conclude that in this elderly patient population with ER-alpha-positive tumors, ER-beta mRNA was neither predictive of response to preoperative toremifene nor provided additional information to the knowledge of ER-alpha mRNA levels, which, conversely, were directly correlated with likelihood of response.
2150. Protein synthesis rates in human muscles: neither anatomical location nor fibre-type composition are major determinants.
作者: B Mittendorfer.;J L Andersen.;P Plomgaard.;B Saltin.;J A Babraj.;K Smith.;M J Rennie.
来源: J Physiol. 2005年563卷Pt 1期203-11页
In many animals the rate of protein synthesis is higher in slow-twitch, oxidative than fast-twitch, glycolytic muscles. To discover if muscles in the human body also show such differences, we measured [13C]leucine incorporation into proteins of anatomically distinct muscles of markedly different fibre-type composition (vastus lateralis, triceps, soleus) after an overnight fast and during infusion of a mixed amino acid solution (75 mg amino acids kg(-1) h(-1)) in nine healthy, young men. Type-1 fibres contributed 83 +/- 4% (mean +/-s.e.m.) of total fibres in soleus, 59 +/- 3% in vastus lateralis and 22 +/- 2% in triceps. The basal myofibrillar and sarcoplasmic protein fractional synthetic rates (FSR, % h(-1)) were 0.034 +/- 0.001 and 0.064 +/- 0.001 (soleus), 0.031 +/- 0.001 and 0.060 +/- 0.001 (vastus), and 0.027 +/- 0.001 and 0.055 +/- 0.001 (triceps). During amino acid infusion, myofibrillar protein FSR increased to 3-fold, and sarcoplasmic to 2-fold basal values (P < 0.001). The differences between muscles, although significant statistically (triceps versus soleus and vastus lateralis, P < 0.05), were within approximately 15%, biologically probably insignificant. The rates of collagen synthesis were not affected by amino acid infusion and varied by < 5% between muscles and experimental conditions.
2151. Dopamine transporter gene associated with diminished subjective response to amphetamine.
作者: David C Lott.;Soo-Jeong Kim.;Edwin H Cook.;Harriet de Wit.
来源: Neuropsychopharmacology. 2005年30卷3期602-9页
Individual variability in responses to stimulant drugs may influence risk of stimulant abuse and treatment response. However, the genetic determinants of this variability have yet to be elucidated. The dopamine transporter is an important site of amphetamine action. Therefore, the dopamine transporter gene (DAT1) is a logical candidate gene to study. Using a drug challenge approach, we tested for association between DAT1 genotype and subjective responses to amphetamine in healthy adults. Volunteers participated in a double-blind, crossover design, randomly receiving placebo, 10 mg, and 20 mg oral D-amphetamine, and completed self-report measures on subjective effects including anxiety and euphoria. Subjects were genotyped for the DAT1 3'-untranslated region VNTR polymorphism and divided into groups based on genotype: homozygous for nine repeats (9/9, N=8), heterozygous (9/10, N=36) and homozygous for 10 repeats (10/10, N=52). The effects of amphetamine on ratings of Feel Drug, Anxiety, and Euphoria were examined with ANCOVA. In 9/10 and 10/10 subjects, amphetamine produced its expected effects of increased Euphoria, Anxiety, and Feel Drug (p<0.01). However, in 9/9 subjects, the effects of amphetamine were indistinguishable from placebo, suggesting that the 9/9 genotype has diminished subjective response to acute amphetamine. Interestingly, recent findings also implicate the 9/9 genotype in decreased therapeutic response to the stimulant methylphenidate in ADHD children. The current findings have important implications for understanding the genetic determinants of variability in stimulant response and risk of abuse.
2152. IFN-beta treatment modulates the CD28/CTLA-4-mediated pathway for IL-2 production in patients with relapsing-remitting multiple sclerosis.
作者: C Espejo.;L Brieva.;G Ruggiero.;J Río.;X Montalban.;E M Martínez-Cáceres.
来源: Mult Scler. 2004年10卷6期630-5页
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system probably mediated by Th1 lymphocytes. IFN-beta is an established therapy for relapsing MS patients, although the mechanisms underlying its efficacy are yet to be well characterized. We determined IL-2 production, CD25 expression and T-cell proliferation from relapsing-remitting MS patients before and three months after starting therapy. A decrease in the percentage of CD80-induced IL-2-producing cells was observed after in vivo IFN-beta treatment. These data support that one of the immunomodulatory effects of IFN-beta treatment in MS may be a limitation of the autoimmune response modifying the CD80:CD28/CTLA-4 pathway.
2153. Expression of apoptosis-related proteins in advanced uterine cervical cancer after balloon-occluded arterial infusion chemotherapy as an indicator of the efficiency of this therapy.
作者: Eri Okamoto.;Toshiyuki Sumi.;Fumiko Misugi.;Hiroyuki Nobeyama.;Kanae Hattori.;Hiroyuki Yoshida.;Yoshinari Matsumoto.;Tomoyo Yasui.;Ken-Ichi Honda.;Osamu Ishiko.
来源: Int J Mol Med. 2005年15卷1期41-7页
We previously reported satisfactory therapeutic results of cisplatin-based cyclic balloon-occluded arterial infusion chemotherapy (BOAI) as neoadjuvant chemotherapy, which enabled treatment by hysterectomy in patients with advanced cervical cancer. We also reported expression of apoptosis among these patients and determined that the bax gene is related to this apoptosis. In the present study, we investigated the relationship between the effectiveness of BOAI therapy and expression of apoptosis regulatory genes and proteins in these cases. The subjects were 27 women with advanced cervical cancer classified as FIGO (International Federation of Gynecology and Obstetrics) stage III or higher who were admitted to the Department of Gynecology, Osaka City University Medical School Hospital between 2000 and 2003. All patients were treated by BOAI, and expression of cancer cell apoptosis was examined by the TUNEL method, expression of bax, bcl-2 and bcl-xL proteins were examined by immunohistochemistry, and expression of bax, bcl-2 and bcl-xL mRNA was examined by quantitative RT-PCR before and 3 days after BOAI. The effectiveness of BOAI therapy was thus determined. The 20 patients in whom BOAI was effective showed significantly higher expression of the bax protein and gene after BOAI, and cancer cell apoptosis was accelerated. On the other hand, the 7 patients in whom BOAI was ineffective showed significantly higher expression of the bcl-xL protein and gene after BOAI. These results suggest that bax/bcl-xL expression can be used as an indicator of the effectiveness of BOAI therapy.
2154. Berberine is a novel cholesterol-lowering drug working through a unique mechanism distinct from statins.
作者: Weijia Kong.;Jing Wei.;Parveen Abidi.;Meihong Lin.;Satoru Inaba.;Cong Li.;Yanling Wang.;Zizheng Wang.;Shuyi Si.;Huaining Pan.;Shukui Wang.;Jingdan Wu.;Yue Wang.;Zhuorong Li.;Jingwen Liu.;Jian-Dong Jiang.
来源: Nat Med. 2004年10卷12期1344-51页
We identify berberine (BBR), a compound isolated from a Chinese herb, as a new cholesterol-lowering drug. Oral administration of BBR in 32 hypercholesterolemic patients for 3 months reduced serum cholesterol by 29%, triglycerides by 35% and LDL-cholesterol by 25%. Treatment of hyperlipidemic hamsters with BBR reduced serum cholesterol by 40% and LDL-cholesterol by 42%, with a 3.5-fold increase in hepatic LDLR mRNA and a 2.6-fold increase in hepatic LDLR protein. Using human hepatoma cells, we show that BBR upregulates LDLR expression independent of sterol regulatory element binding proteins, but dependent on ERK activation. BBR elevates LDLR expression through a post-transcriptional mechanism that stabilizes the mRNA. Using a heterologous system with luciferase as a reporter, we further identify the 5' proximal section of the LDLR mRNA 3' untranslated region responsible for the regulatory effect of BBR. These findings show BBR as a new hypolipidemic drug with a mechanism of action different from that of statin drugs.
2155. Interferon-alpha affects the tumour necrosis factor-alpha content of mast cells in human nasal mucosa. A pilot study in allergic patients.
作者: Rossella Riccardi-Arbi.;Stefano Bacci.;Paolo Romagnoli.;Lucio Rucci.
来源: Ital J Anat Embryol. 2004年109卷2期115-22页
Human nasal mucosal mast cells contain and secrete tumour necrosis factor (TNF)-alpha, which in turn can stimulate histamine secretion by these cells. Interferon (IFN)-alpha can inhibit TNF-alpha secretion by mast cells in vitro. We have addressed the interrelationships between IFN-alpha and the content in TNF-alpha and number of mast cells in vivo, in the human nasal mucosa. Biopsies were taken from two healthy control patients, two allergic patients and two more allergic patients treated topically with IFN-alpha for two weeks; biopsies from the last two patients were taken both before and after stimulation with the specific allergen. Mast cells were counted upon tagging with rhodaminated avidin and by indirect immunofluorescence for TNF-alpha. Data were subjected to analysis of variance. Mast cell numbers were significantly lower in all allergic patients than in controls (P<0.001). Upon IFN-alpha treatment, TNF-alpha positive mast cells were less than in allergic, untreated patients and the opposite was true for TNF-alpha negative mast cells (p<0.05). Allergen challenge caused selective, significant decrease only in the number of TNF-alpha negative mast cells (p<0.05). The results suggest that upon topical IFN-alpha treatment: (1) mast cells stores of TNF-alpha in the nasal mucosa of allergic patients are decreased; and (2) only TNF-alpha negative cells degranulate in response to allergen challenge. Therefore, one may expect that such a treatment reduces the TNF-alpha burden to the mucosa in these patients.
2156. Effect of influenza virus vaccine on the expression of human immunodeficiency virus co-receptor CCR5.
作者: Rajivi P Rucker.;Noorbibi K Day.;Robert A Good.;Wasu Kamchaisatian.;Patricia Emmanuel.;John W Sleasman.;Cathy Mayeski.;Elmer Dinglasan.;Soichi Haraguchi.;Nutthapong Tangsinmankong.
来源: Ann Allergy Asthma Immunol. 2004年93卷3期272-6页
Administration of influenza vaccine to human immunodeficiency virus (HIV)-infected children can lead to increased viral load. CCR5 and CXCR4 are known to play an important role in HIV cell entry and viral replication.
2157. Histological evidence that infliximab treatment leads to downregulation of inflammation and tissue remodelling of the synovial membrane in spondyloarthropathy.
作者: E Kruithof.;D Baeten.;F Van den Bosch.;H Mielants.;E M Veys.;F De Keyser.
来源: Ann Rheum Dis. 2005年64卷4期529-36页
To confirm and extend the immunopathological evidence of effects of infliximab on the synovium in active spondyloarthropathy.
2158. Efficacy of imiquimod for the expression of Bcl-2, Ki67, p53 and basal cell carcinoma apoptosis.
Imiquimod is a modifier of the immune response that has been proven to be an effective treatment for basal cell carcinoma (BCC). However, its mechanism of action is still unknown.
2159. Expression profiling of insulin action in human myotubes: induction of inflammatory and pro-angiogenic pathways in relationship with glycogen synthesis and type 2 diabetes.
作者: Lars Hansen.;Michael Gaster.;Edward J Oakeley.;Klaus Brusgaard.;Eva-Maria Damsgaard Nielsen.;Henning Beck-Nielsen.;Oluf Pedersen.;Brian A Hemmings.
来源: Biochem Biophys Res Commun. 2004年323卷2期685-95页
Myotube cultures from patients with type 2 diabetes mellitus (T2DM) represent an experimental in vitro model of T2DM that offers a possibility to perform gene expression studies under standardized conditions. During a time-course of insulin stimulation (1 microM) at 5.5 mM glucose for 0 (no insulin), 0.5, 1, 2, 4, 8, and 24 h, mRNA contents were analyzed in human myotubes for each time point using Affymetrix DNA chip technology. Insulin treatment induced an inflammatory and pro-angiogenic response in the myotubes, with expression of early response factors followed by inflammatory chemokines, metabolic enzymes, and finally cell cycle regulating genes. One-hundred-forty-four genes were differentially expressed in myotubes from donors with type 2 diabetes compared with control subjects, including HSP70, apolipoprotein D/E, tropomyosin, myosin, and actin previously reported from in vivo studies of diabetic skeletal muscle. We conclude, (i) that insulin induces a time-dependent inflammatory and pro-angiogenic transcriptional response in cultured human myotubes, (ii) that myotubes in vitro retain a gene expression pattern specific for type 2 diabetes and sharing five genes with that of type 2 diabetic skeletal muscle in vivo, and (iii) that insulin, despite similar metabolic effects of glucose uptake and glycogen synthesis, regulates different pools of genes in skeletal muscle during in vivo and in vitro conditions.
2160. Effects of vitamin E supplementation on intracellular antioxidant enzyme production in adolescents with type 1 diabetes and early microangiopathy.
作者: Francesco Chiarelli.;Francesca Santilli.;Giuseppe Sabatino.;Annalisa Blasetti.;Stefano Tumini.;Francesco Cipollone.;Andrea Mezzetti.;Alberto Verrotti.
来源: Pediatr Res. 2004年56卷5期720-5页
Defective intracellular antioxidant enzyme production (IAP) has been demonstrated in adults with diabetic nephropathy. To evaluate the effects on IAP of vitamin E administration in adolescents with type 1 diabetes and early signs of microangiopathy, 12 adolescents (aged 11-21 y; diabetes duration 10-18) were studied. Eight had retinopathy [background (four), preproliferative (three), or proliferative (one)], four had persistent microalbuminuria, and seven had both. Skin fibroblasts were obtained by biopsies and cultured in Dulbecco's modified Eagle's medium. CuZn superoxide dismutase (SOD), MnSOD, catalase (CAT), and glutathione-peroxidase (GPX) activity and mRNA expression were measured before and after 3 mo of synthetic vitamin E supplementation (600 mg twice daily); on both occasions, IAP was evaluated at different ex vivo glucose concentrations (5 and 22 mM). Ten adolescents with type 1 diabetes (aged 12-20 y) without angiopathy and eight healthy volunteers (aged 15-22 y) participated as control subjects. Vitamin E serum levels were measured throughout the study. In normal glucose concentrations, CuZnSOD, MnSOD, CAT, and GPX activity and mRNA expression were not different among the groups. In high glucose, CuZnSOD activity and mRNA increased similarly in all groups [angiopathics: 0.96 +/- 0.30 U/mg protein; 9.9 +/- 3.2 mRNA/glyceraldehyde-3-phosphate dehydrogenase). CAT and GPX activity and mRNA did not increase in high glucose only in adolescents with angiopathy (0.35 +/- 0.09; 4.2 +/- 0.1 and 0.52 +/- 0.14; 2.4 +/- 0.9, respectively). MnSOD did not change in any group. Vitamin E supplementation had no effect on any enzymatic activity and mRNA in both normal and hyperglycemic conditions. Adolescents with early signs of diabetic angiopathy have defective IAP and activity, which are not modified by vitamin E.
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