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1.
J Clin Endocrinol Metab ; 105(8)2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32589738

RESUMO

CONTEXT: Patients with classic congenital adrenal hyperplasia (CAH) often require supraphysiologic glucocorticoid doses to suppress adrenocorticotropic hormone (ACTH) and control androgen excess. Nevanimibe hydrochloride (ATR-101), which selectively inhibits adrenal cortex function, might reduce androgen excess independent of ACTH and thus allow for lower glucocorticoid dosing in CAH. 17-hydroxyprogesterone (17-OHP) and androstenedione are CAH biomarkers used to monitor androgen excess. OBJECTIVE: Evaluate the efficacy and safety of nevanimibe in subjects with uncontrolled classic CAH. DESIGN: This was a multicenter, single-blind, dose-titration study. CAH subjects with baseline 17-OHP ≥4× the upper limit of normal (ULN) received the lowest dose of nevanimibe for 2 weeks followed by a single-blind 2-week placebo washout. Nevanimibe was gradually titrated up if the primary outcome measure (17-OHP ≤2× ULN) was not met. A total of 5 nevanimibe dose levels were possible (125, 250, 500, 750, 1000 mg twice daily). RESULTS: The study enrolled 10 adults: 9 completed the study, and 1 discontinued early due to a related serious adverse event. At baseline, the mean age was 30.3 ±â€…13.8 years, and the maintenance glucocorticoid dose, expressed as hydrocortisone equivalents, was 24.7 ±â€…10.4 mg/day. Two subjects met the primary endpoint, and 5 others experienced 17-OHP decreases ranging from 27% to 72% during nevanimibe treatment. The most common side effects were gastrointestinal (30%). There were no dose-related trends in adverse events. CONCLUSIONS: Nevanimibe decreased 17-OHP levels within 2 weeks of treatment. Larger studies of longer duration are needed to further evaluate its efficacy as add-on therapy for CAH.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Ureia/análogos & derivados , 17-alfa-Hidroxiprogesterona/metabolismo , Administração Oral , Adolescente , Córtex Suprarrenal/efeitos dos fármacos , Córtex Suprarrenal/metabolismo , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/diagnóstico , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Androstenodiona/sangue , Androstenodiona/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos Cross-Over , Relação Dose-Resposta a Droga , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento , Ureia/administração & dosagem , Ureia/efeitos adversos , Adulto Jovem
2.
Invest New Drugs ; 38(5): 1421-1429, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31984451

RESUMO

Background Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with very limited treatment options. Nevanimibe HCl (formerly ATR-101), a novel adrenal-specific sterol O-acyltransferase 1 (SOAT1) inhibitor, has been shown in nonclinical studies to decrease adrenal steroidogenesis at lower doses and to cause apoptosis of adrenocortical cells at higher doses. Methods This phase 1, multicenter, open-label study assessed the safety and pharmacokinetics (PK) of nevanimibe in adults with metastatic ACC (NCT01898715). A "3 + 3" dose-escalation design was used. Adverse events (AEs), PK, and tumor response based on Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 were evaluated every 2 months. Results 63 patients with metastatic ACC, all of whom had previously failed systemic chemotherapy and only 2 of whom were mitotane-naïve, were dosed with oral nevanimibe at doses ranging from 1.6 mg/kg/day to 158.5 mg/kg/day. Subjects who did not experience tumor progression or a dose-limiting toxicity (DLT) could continue to receive additional cycles. No patients experienced a complete or partial response; however, 13 of the 48 (27%) patients who underwent imaging at 2 months had stable disease (SD), and 4 of these had SD > 4 months. In addition, drug-related adrenal insufficiency, considered a pharmacologic effect of nevanimibe, was observed in two patients. The most common treatment-emergent AEs were gastrointestinal disorders (76%), including diarrhea (44%) and vomiting (35%). A maximum tolerated dose (MTD) could not be defined, as very few dose-limiting toxicities (DLTs) occurred. Because the large number of tablets required at the highest dose (i.e., ~24 tablets/day) resulted in low-grade gastrointestinal adverse effects, a maximum feasible dose of 128.2 mg/kg/day was established as a dose that could be taken on a long-term basis. Conclusions This study demonstrated the safety of nevanimibe at doses of up to ~6000 mg BID. As the total number of tablets required to achieve an MTD exceeded practical administration limits, a maximum feasible dose was defined. Given that the expected exposure levels necessary for an apoptotic effect could not be achieved, the current formulation of nevanimibe had limited efficacy in patients with advanced ACC.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Carcinoma Adrenocortical/tratamento farmacológico , Esterol O-Aciltransferase/antagonistas & inibidores , Ureia/análogos & derivados , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Comprimidos , Ureia/administração & dosagem , Ureia/efeitos adversos , Ureia/sangue , Ureia/farmacocinética
3.
Menopause ; 25(8): 862-869, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29533369

RESUMO

OBJECTIVE: Seventy percent of postmenopausal women experience vasomotor symptoms, which can be highly disruptive and persist for years. Hormone therapy and other treatments have variable efficacy and/or side effects. Neurokinin B signaling increases in response to estrogen deficiency and has been implicated in hot flash (HF) etiology. We recently reported that a neurokinin 3 receptor (NK3R) antagonist reduces HF in postmenopausal women after 4 weeks of treatment. In this article we report novel data from that study, which shows the detailed time course of this effect. METHODS: Randomized, double-blind, placebo-controlled, single-center, crossover trial of an oral NK3R antagonist (MLE4901) for vasomotor symptoms in women aged 40 to 62 years, experiencing ≥7 HF/24 hours some of which were reported as bothersome or severe (Clinicaltrials.gov NCT02668185). Thirty-seven women were randomized and included in an intention-to-treat analysis. To ascertain the therapeutic profile of MLE4901, a post hoc time course analysis was completed. RESULTS: By day 3 of treatment with MLE4901, HF frequency reduced by 72% (95% CI, -81.3 to -63.3%) compared with baseline (51 percentage point reduction compared with placebo, P < 0.0001); this effect size persisted throughout the 4-week dosing period. HF severity reduced by 38% compared with baseline by day 3 (95% CI, -46.1 to -29.1%) (P < 0.0001 compared with placebo), bother by 39% (95% CI, -47.5 to -30.1%) (P < 0.0001 compared with placebo), and interference by 61% (95% CI, -79.1 to -43.0%) (P = 0.0006 compared with placebo); all continued to improve throughout the 4-week dosing period (to -44%, -50%, and -70%, respectively by day 28, all P < 0.0001 compared with placebo). CONCLUSIONS: NK3R antagonism rapidly relieves vasomotor symptoms without the need for estrogen exposure.

4.
Lancet ; 389(10081): 1809-1820, 2017 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-28385352

RESUMO

BACKGROUND: Hot flushes affect 70% of menopausal women and often severely impact physical, psychosocial, sexual, and overall wellbeing. Hormone replacement therapy is effective but is not without risk. Neurokinin B signalling is increased in menopausal women, and has been implicated as an important mediator of hot flushes. METHODS: This phase 2, randomised, double-blind, placebo-controlled, single-centre, crossover trial assessed the effectiveness of an oral neurokinin 3 receptor antagonist (MLE4901) on menopausal hot flushes. Eligible participants were healthy women aged 40-62 years, having seven or more hot flushes in every 24 h of which some were reported as being severe or bothersome, who had not had a menstrual period for at least 12 months, and who had not been taking any medication shown to improve menopausal flushes in the preceding 8 weeks. Participants received 4 weeks of MLE4901 (40 mg, orally, twice daily) and placebo (orally, twice daily) in random order separated by a 2 week washout period. Randomisation was completed by a central computer, and participants were allocated to treatment number in numerical order. The primary outcome was the total number of hot flushes during the final week of both treatment periods. Analyses were by intention to treat and per protocol using generalised linear mixed models and standard crossover analysis. All analyses were prespecified in the study protocol. The trial is registered at ClinicalTrials.gov, number NCT02668185. FINDINGS: 68 women were screened between Feb 3 and Oct 10, 2016, of which 37 were randomly assigned and included in an intention-to-treat analysis. 28 participants completed the trial and were included in a per-protocol analysis. MLE4901 significantly reduced the total weekly number of hot flushes by 45 percentage points (95% CI 22-67) compared with the placebo (intention-to-treat adjusted means: placebo 49·01 [95% CI 40·81-58·56] vs MLE4901 19·35 [15·99-23·42]; adjusted estimate of difference 29·66 [17·39-42·87], p<0·0001). Treatment was well tolerated. Three participants developed a transaminase rise (alanine aminotransferase 4·5-5·9 times the upper limit of normal) with a normal bilirubin 28 days after starting MLE4901, which normalised within 90 days. INTERPRETATION: Treatment with a neurokinin 3 receptor antagonist (MLE4901) could be practice changing as it safely and effectively relieves hot flush symptoms without the need for oestrogen exposure. Larger scale studies of longer duration are now indicated. FUNDING: UK Medical Research Council and National Institute for Health Research.


Assuntos
Fogachos/tratamento farmacológico , Menopausa/fisiologia , Receptores da Neurocinina-3/antagonistas & inibidores , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Terapia de Reposição Hormonal/métodos , Fogachos/etiologia , Humanos , Menopausa/genética , Menopausa/psicologia , Pessoa de Meia-Idade , Receptores da Neurocinina-3/genética , Receptores da Neurocinina-3/uso terapêutico , Resultado do Tratamento
5.
Endocr Relat Cancer ; 19(5): 657-66, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22807497

RESUMO

Pasireotide (SOM230) is a novel multireceptor-targeted somatostatin (sst) analog with high binding affinity for sst receptor subtype 1, 2, 3 (sst(1,2,3)) and sst(5). Because of this binding profile, pasireotide may offer symptom control in patients with neuroendocrine tumors (NETs) and carcinoid syndrome no longer responsive to octreotide LAR. This was a phase II, open-label, multicenter study of pasireotide in patients with advanced NET whose symptoms of carcinoid syndrome (diarrhea/flushing) were inadequately controlled by octreotide LAR. Patients received s.c. pasireotide 150 µg twice daily (bid), escalated to a maximum dose of 1200 µg bid until a clinical response was achieved. Forty-four patients were evaluated for efficacy and 45 for tolerability. Pasireotide 600-900 µg s.c. bid effectively controlled the symptoms of diarrhea and flushing in 27% of patients. Evaluation of tumor response in 23 patients showed 13 with stable disease and ten with progressive disease at study end. The most common drug-related adverse events were nausea (27%), abdominal pain (20%), weight loss (20%), and hyperglycemia (16%) and most were of mild or moderate severity. Pasireotide 600-900 µg s.c. bid was effective and generally well tolerated in controlling the symptoms of carcinoid syndrome in 27% of patients with advanced NET refractory or resistant to octreotide LAR therapy.


Assuntos
Antineoplásicos/administração & dosagem , Diarreia/tratamento farmacológico , Rubor/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Tumores Neuroendócrinos/tratamento farmacológico , Somatostatina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Resistencia a Medicamentos Antineoplásicos , Feminino , Fármacos Gastrointestinais/efeitos adversos , Fármacos Gastrointestinais/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Qualidade de Vida , Somatostatina/administração & dosagem , Somatostatina/efeitos adversos , Somatostatina/farmacocinética , Resultado do Tratamento
6.
Endocrine ; 42(2): 366-74, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22527887

RESUMO

A randomized, double-blind, placebo-controlled, cross-over, dose-escalating, single-center study was conducted to evaluate the safety, tolerability, and pharmacokinetic (PK) profile of multiple once-daily (qd) subcutaneous (sc) doses of pasireotide in healthy male subjects. Subjects received pasireotide 50, 200, or 600 µg sc qd for 14 days and placebo in separate sequences. Thirty-three subjects were randomized. The most frequently reported drug-related adverse events were injection-site reactions (n = 18), diarrhea (n = 14) and nausea (n = 10), which were mostly mild or moderate in intensity. Pasireotide 600 µg sc was associated with pre- and post-prandial elevations in glucose levels relative to placebo; however, this effect was less pronounced on day 14 compared with day 1. PK steady state appeared to be achieved after 3 days of dosing and PK exposures had a moderate accumulation of 20-40 % across doses. Pasireotide demonstrated fast absorption (T(max,ss): 0.25-0.5 h), low clearance (CL/F(ss): 8.10-9.03 L/h), long effective half-life (T(½,eff): ~12 h, on average between 9.7 and 13.1 h for 50, 200, and 600 µg sc qd), and large volume of distribution (V(z)/F(ss): 251-1,091 L) at steady state. Dose proportionality was confirmed for C(max,ss); other PK parameters (C(max), AUC(0-24 h) and AUC(tau)) were approximately dose proportional. Growth hormone inhibition was observed with pasireotide 200 and 600 µg sc qd. Gallbladder volume increased post-prandially with pasireotide 200 and 600 µg sc qd, which appeared to correlate with reduced levels of cholecystokinin at these doses. Pasireotide was generally well tolerated up to the tested dose of 600 µg qd, with a linear and time-independent PK profile after sc qd dosing in healthy subjects.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Somatostatina/análogos & derivados , Adulto , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/sangue , Antineoplásicos Hormonais/farmacocinética , Colecistocinina/sangue , Estudos Cross-Over , Diarreia/sangue , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Método Duplo-Cego , Vesícula Biliar/efeitos dos fármacos , Vesícula Biliar/patologia , Meia-Vida , Hormônio do Crescimento Humano/sangue , Humanos , Hiperglicemia/sangue , Hiperglicemia/induzido quimicamente , Injeções Subcutâneas , Masculino , Taxa de Depuração Metabólica , Náusea/sangue , Náusea/induzido quimicamente , Tamanho do Órgão/efeitos dos fármacos , Somatostatina/administração & dosagem , Somatostatina/efeitos adversos , Somatostatina/sangue , Somatostatina/farmacocinética , Taquifilaxia , Adulto Jovem
7.
Diabetes Care ; 29(5): 1016-23, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16644631

RESUMO

OBJECTIVE: We sought to evaluate the effects of muraglitazar, a dual (alpha/gamma) peroxisome proliferator-activated receptor (PPAR) activator within the new glitazar class, on hyperglycemia and lipid abnormalities. RESEARCH DESIGN AND METHODS: A double-blind, randomized, controlled trial was performed in 1,159 patients with type 2 diabetes inadequately controlled with metformin. Patients received once-daily doses of either 5 mg muraglitazar or 30 mg pioglitazone for a total of 24 weeks in addition to open-label metformin. Patients were continued in a double-blind fashion for an additional 26 weeks. RESULTS: Analyses were conducted at week 24 for HbA1c (A1C) and at week 12 for lipid parameters. Mean A1C at baseline was 8.12 and 8.13% in muraglitazar and pioglitazone groups, respectively. At week 24, muraglitazar reduced mean A1C to 6.98% (-1.14% from baseline), and pioglitazone reduced mean A1C to 7.28% (-0.85% from baseline; P < 0.0001, muraglitazar vs. pioglitazone). At week 12, muraglitazar and pioglitazone reduced mean plasma triglyceride (-28 vs. -14%), apolipoprotein B (-12 vs. -6%), and non-HDL cholesterol (-6 vs. -1%) and increased HDL cholesterol (19 vs. 14%), respectively (P < 0.0001 vs. pioglitazone for all comparisons). At week 24, weight gain (1.4 and 0.6 kg, respectively) and edema (9.2 and 7.2%, respectively) were observed in the muraglitazar and pioglitazone groups; at week 50, weight gain and edema were 2.5 and 1.5 kg, respectively, and 11.8 and 8.9%, respectively. At week 50, heart failure was reported in seven patients (five with muraglitazar and two with pioglitazone), and seven deaths occurred: three from sudden death, two from cerebrovascular accident, and one from pancreatic cancer in the muraglitazar group and one from perforated duodenal ulcer in the pioglitazone group. CONCLUSIONS: We found that 5 mg muraglitazar resulted in greater improvements in A1C and lipid parameters than a submaximal dose of 30 mg pioglitazone when added to metformin. Weight gain and edema were more common when muraglitazar was compared with a submaximal dose of pioglitazone.


Assuntos
Glicemia/metabolismo , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glicina/análogos & derivados , Metformina/uso terapêutico , Oxazóis/uso terapêutico , Tiazolidinedionas/uso terapêutico , Triglicerídeos/sangue , Adulto , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oxazóis/efeitos adversos , PPAR alfa/agonistas , PPAR gama/agonistas , Pioglitazona , Tiazolidinedionas/efeitos adversos
8.
Endocrine ; 28(2): 181-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16388091

RESUMO

Thiazolidinediones (TZD) are effective agents for the treatment of hyperglycemia, and appear ideal in diabetic patients with progressive or end-stage renal disease because of its predominant hepatic clearance. Troglitazone, the first available TZD for clinical use, was withdrawn due to safety concerns; however, studies completed with this agent can provide a better understanding of the class effect of TZDs. This study was an open-label, controlled clinical trial examining the safety and efficacy of troglitazone in type 2 diabetic patients with end-stage renal disease (ESRD). Twelve subjects were randomized to parallel study groups and treated for 6 mo with or without troglita-zone at a maximum dose of 600 mg/d in addition to continuing their previous diabetes medications (insulin or sulfonylurea). The results showed no significant differences in glycemic control with or without troglit-azone treatment for 6 mo. However, there was a significant reduction in insulin dosage with troglitazone treatment (22.9 +/- 7.3 units/d) than without troglita-zone treatment (54 +/- 12.9 units/d) (p < 0.05), as well as the change in the insulin dosage from baseline between the two groups (troglitazone, -8.4 units vs control, +4.3 units, p < 0.05). Weight changes and aspartate amino-transferase levels greater than 1.5 times the upper limit of normal were not observed in participants of either treatment group. This study demonstrates that troglit-azone was safe and effective for the treatment of hyper-glycemia in patients requiring dialysis, and strongly supports the clinical use of currently available TZDs in diabetic patients with renal failure.


Assuntos
Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Falência Renal Crônica/complicações , Tiazolidinedionas/uso terapêutico , Glicemia/efeitos dos fármacos , Cromanos/efeitos adversos , Cromanos/farmacocinética , Diabetes Mellitus Tipo 2/complicações , Feminino , Hemoglobina A/efeitos dos fármacos , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Insulina/administração & dosagem , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Tiazolidinedionas/efeitos adversos , Tiazolidinedionas/farmacocinética , Troglitazona
9.
Clin Ther ; 24(9): 1426-38, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12380634

RESUMO

BACKGROUND: Because both type 2 diabetes and elevated plasma lipid levels are important independent risk factors for cardiovascular disease and coronary heart disease, the choice of an antihyperglycemic agent for patients with type 2 diabetes--in whom abnormal plasma lipid levels are often seen-should take into account effects on lipids as well as on markers of glycemic control. OBJECTIVE: This study assessed the effects on lipid levels of glyburide/metformin tablets in the treatment of type 2 diabetes, particularly in a group of patients who had poor glycemic control and dyslipidemia at baseline. METHODS: This 52-week, open-label study was an extension of a 32-week, double-blind, placebo-controlled study. The patient population was drawn from 3 groups: those who completed the double-blind study, those who were discontinued from the double-blind study, and those who were ineligible for the double-blind study based on predefined measures of glycemic control (screening fasting plasma glucose > 240 mg/dL and glycosylated hemoglobin [HbA1c] < or = 12%, or HbA1c 11%-12%) and were directly enrolled in the open-label extension study. Patients with an HbA1c of < 9% received glyburide/ metformin tablets 1.25 mg/250 mg BID; those with an HbA1c > or = 9% received glyburide/ metformin tablets 2.5 mg/500 mg BID. Changes in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) levels were assessed for 52 weeks. RESULTS: The study population included 828 patients: 515 who completed the double-blind study, 138 who were discontinued from the double-blind study, and 175 who were enrolled directly. Direct enrollees had poor glycemic control and dyslipidemia at baseline. Improvements in plasma lipid levels were seen as early as week 13. At week 52, the mean change in TC from baseline was -8.0 mg/dL for the total population (95% CI, -10.9 to -5.2; P < 0.05) and -23.2 mg/dL for direct enrollees (95% CI, -30.1 to -16.4; P < 0.05). The mean decrease in LDL-C from baseline for the total population was 2.86 mg/dL (95% CI, -5.3 to -0.4; P < 0.05), compared with a reduction of 13.3 mg/dL for direct enrollees (95% CI, -18.5 to -8.1; P < 0.05). Mean HDL-C levels were minimally affected. Mean TG levels decreased by 27.8 mg/dL for the entire population (95% CI, -42.9 to -12.8; P < 0.05) and by 99.7 mg/dL for direct enrollees (95% CI, -152.5 to -46.8; P < 0.05). CONCLUSION: In this open-label extension study, treatment with glyburide/ metformin tablets for type 2 diabetes had a durable, favorable effect on lipid levels, particularly in those with poor glycemic control and dyslipidemia at baseline.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glibureto/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Glicemia/análise , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Quimioterapia Combinada , Jejum/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Triglicerídeos/sangue
10.
Diabetes Care ; 25(9): 1597-602, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12196433

RESUMO

OBJECTIVE: To compare the effects of intravenously administered long-acting insulin analog glargine and regular human insulin on activation and deactivation of endogenous glucose output (EGO) and peripheral glucose uptake. RESEARCH DESIGN AND METHODS: In this single-center, randomized, double-blind, crossover euglycemic glucose clamp study, 15 healthy male volunteers (aged 27 +/- 4 years, BMI 24.2 +/- 0.7 kg/m(2) [mean +/- SE]) received a primed continuous intravenous infusion of 40 mU/m(2) of insulin glargine or regular human insulin on 2 different study days in a randomized order. Euglycemia was maintained at 90 mg/dl using a simultaneous variable intravenous infusion of 20% dextrose containing D-[3-(3)H]glucose. EGO and peripheral glucose disposal kinetics were determined during a 4-h insulin infusion activation period and a 3-h deactivation period. RESULTS: The results demonstrated no significant difference in activation or deactivation kinetics with respect to EGO and peripheral glucose disposal between insulin glargine and regular human insulin when given intravenously. The mean +/- SE time required for 50% suppression of EGO after insulin infusion was 73 +/- 23 min for regular insulin and 57 +/- 20 min for insulin glargine (NS). The mean maximum rate of glucose disposal was 10.10 +/- 0.77 and 9.90 +/- 0.85 mg. kg(-1). min(-1) for regular insulin and insulin glargine, respectively (NS). The mean time required for 50% suppression of incremental glucose disposal rate (GDR), defined as the time required for activation from the basal glucose disappearance rate (R(d)) to half-maximum insulin-stimulated R(d), was 32 +/- 5 and 42 +/- 10 min for regular insulin and insulin glargine, respectively (NS). The time required for deactivation from maximum insulin-stimulated GDR to half-maximum GDR after cessation of insulin infusion was 63 +/- 5 and 57 +/- 4 min for regular insulin and insulin glargine, respectively (NS). CONCLUSIONS: Activation and deactivation kinetics of EGO and peripheral glucose uptake as well as absolute disposal rate are similar between regular human insulin and insulin glargine when administered intravenously. Thus, the various biological actions of these insulin preparations when given subcutaneously are completely due to their different absorption kinetics.


Assuntos
Glucose/farmacocinética , Hipoglicemiantes/administração & dosagem , Insulina/análogos & derivados , Insulina/administração & dosagem , Adulto , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Estudos Cross-Over , Ácidos Graxos não Esterificados/sangue , Técnica Clamp de Glucose , Humanos , Hipoglicemiantes/sangue , Injeções Intravenosas , Insulina/sangue , Insulina Glargina , Insulina de Ação Prolongada , Masculino , Trítio
11.
Metabolism ; 51(9): 1171-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200763

RESUMO

The metabolic actions of insulin and insulin-like growth factor-1 (IGF-1) were compared in cultured skeletal muscle cells from nondiabetic (ND) and type 2 diabetic subjects. Insulin stimulated glucose uptake with comparable sensitivity in ND (EC(50) = 2.0 +/- 0.7 nmol/L) and diabetic (1.3 +/- 0.4) cells. IGF-1 sensitivity for uptake stimulation was similar in ND (EC(50) = 0.30 +/- 0.06 nmol/L) and type 2 cells (0.37 +/- 0.01). In ND cells, insulin and IGF-1 were equally potent for stimulation of glucose uptake and glycogen synthase (GS) activity. However, in diabetic cells, maximal insulin stimulation of both responses was only half of the increases due to IGF-1. Final absolute activities after IGF-1 stimulation were still lower in diabetic cells compared with cells from ND subjects. Hormonal stimulation of Akt phosphorylation exhibited the same behavior as metabolic responses; comparable for insulin and IGF-1 in ND muscle, while IGF-1 was significantly more effective in diabetic cells. Both insulin receptor (IR) binding and receptor protein expression were similar in ND and diabetic cells. IGF-1 binding and receptor protein expression were not significantly different in diabetic compared with ND cells. The expression of IGF-binding proteins (IGFBP) 3, 5, and 6 were similar in ND and diabetic cells; IGFBP-4 was slightly, but significantly higher, in diabetic cells. While insulin and IGF-1 are equally effective on metabolic responses in ND muscle, diabetic muscle cells are markedly more resistant to insulin than IGF-1. The greater metabolic activity of IGF-1 in type 2 diabetic muscle may provide new insights into the mechanisms of insulin resistance in skeletal muscle.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Insulina/farmacologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Adulto , Células Cultivadas , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Insulina/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Valores de Referência , Transdução de Sinais
12.
Diabetes ; 51(2): 443-8, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11812753

RESUMO

Insulin stimulation of phosphatidylinositol (PI) 3-kinase activity is defective in skeletal muscle of type 2 diabetic individuals. We studied the impact of antidiabetic therapy on this defect in type 2 diabetic subjects who failed glyburide treatment by the addition of troglitazone (600 mg/day) or metformin (2,550 mg/day) therapy for 3-4 months. Improvement in glycemic control was similar for the two groups, as indicated by changes in fasting glucose and HbA(1c) levels. Insulin action on whole-body glucose disposal rate (GDR) was determined before and after treatment using the hyperinsulinemic (300 mU x m(-2) x min(-1)) euglycemic (5.0-5.5 mmol/l) clamp technique. Needle biopsies of vastus lateralis muscle were obtained before and after each 3-h insulin infusion. Troglitazone treatment resulted in a 35 +/- 9% improvement in GDR (P < 0.01), which was greater than (P < 0.05) the 22 +/- 13% increase (P < 0.05) after metformin treatment. Neither treatment had any effect on basal insulin receptor substrate-1 (IRS-1)-associated PI 3-kinase activity in muscle. However, insulin stimulation of PI 3-kinase activity was augmented nearly threefold after troglitazone treatment (from 67 +/- 22% stimulation over basal pre-treatment to 211 +/- 62% post-treatment, P < 0.05), whereas metformin had no effect. The troglitazone effect on PI 3-kinase activity was associated with a 46 +/- 22% increase (P < 0.05) in the amount of the p110beta catalytic subunit of PI 3-kinase. Insulin-stimulated Akt activity also increased after troglitazone treatment (from 32 +/- 8 to 107 +/- 32% stimulation, P < 0.05) but was unchanged after metformin therapy. Protein expression of other key insulin signaling molecules (IRS-1, the p85 subunit of PI 3-kinase, and Akt) was unaltered after either treatment. We conclude that the mechanism for the insulin-sensitizing effect of troglitazone, but not metformin, involves enhanced PI 3-kinase pathway activation in skeletal muscle of obese type 2 diabetic subjects.


Assuntos
Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Isoenzimas/metabolismo , Músculo Esquelético/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Tiazóis/uso terapêutico , Tiazolidinedionas , Adulto , Idoso , Feminino , Humanos , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Troglitazona
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