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12
result(s) for
"Leuprolide - toxicity"
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Independent Effects of Testosterone on Lipid Oxidation and VLDL-TG Production: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study
by
GRAVHOLT, Claus H
,
HOUGAARD, David M
,
PEDERSEN, Steen B
in
Administration, Cutaneous
,
Adult
,
Analysis
2013
Low testosterone (T) levels in men have been shown to predict development of the metabolic syndrome, but the effects of T on lipid metabolism are incompletely understood. In a randomized, double-blind, placebo-controlled, crossover study, 12 healthy, young males received gonadotropin-releasing hormone agonist treatment 1 month prior to 3 of 4 trial days to induce castrate levels of T. On trial days, T gel was applied to the body containing either high or low physiological T dose or placebo. On the 4th trial day, participants constituted their own eugonadal controls. Each study comprised a 5-h basal period and a 3-h hyperinsulinemic-euglycemic clamp. Short-term hypogonadism did not affect VLDL triglyceride (TG) secretion, nor did it affect VLDL-TG concentrations. It was, however, characterized by lower total lipid oxidation. In addition, acute rescue with high physiological T increased VLDL-TG secretion during both basal and clamp conditions. These data show that T can act through fast nongenomic pathways in the liver. In addition, the early hypogonadal state is characterized by decreased total lipid oxidation, but whether these changes represent early hypogonadal metabolic dysfunction warrants further investigations. T is not a major determinant of resting VLDL-TG kinetics in men.
Journal Article
Prevention of Osteopenia Induced with a Gonadotropin-Releasing Hormone Agonist in Rats
by
Mitamura, T.
,
Yoshimura, S.
,
Zhou, Y.-F.
in
Animals
,
Body Weight - drug effects
,
Bone Density - drug effects
1999
We investigated the effects of conjugated estrogens as an add-back replacement drug, incadronate sodium as a bisphosphonate, and alfacalcidol as a vitamin D(3) analog on femoral bone mineral density (BMD) and bone mineral content (BMC) in female rats chronically treated with the gonadotropin-releasing hormone (GnRH) agonist leuprorelin acetate. The chemical castration of the rats by the administration of GnRH agonist for 16 weeks reduced the BMD values to 92.3%, 91.3%, and 93.3% of those of the normal control animals in the whole femur, metaphysis, and diaphysis of the femur, respectively. The BMC value was decreased to 91.0% of that of the normal control animals by the chronic GnRH agonist treatment. However, a simultaneous 8-week administration of conjugated estrogens, bisphosphonate, and vitamin D(3) analog markedly augmented the BMC values to 110.3%, 110.1%, and 114.4%, respectively, of those in the rats treated with the GnRH agonist alone. These findings indicate that antiosteoporotic agents could be useful for preventing induced osteopenia under the careful monitoring of biochemical markers of osteoblastic activity or bone resorption and BMD or BMC in patients undergoing GnRH treatment.
Journal Article
Sequence of hormonal therapy and radiotherapy field size in unfavourable, localised prostate cancer (NRG/RTOG 9413): long-term results of a randomised, phase 3 trial
by
Seider, Michael J
,
Jones, Christopher U
,
Lee, W Robert
in
Acetic acid
,
Adenocarcinoma
,
Antigens
2018
The NRG/RTOG 9413 study showed that whole pelvic radiotherapy (WPRT) plus neoadjuvant hormonal therapy (NHT) improved progression-free survival in patients with intermediate-risk or high-risk localised prostate cancer compared with prostate only radiotherapy (PORT) plus NHT, WPRT plus adjuvant hormonal therapy (AHT), and PORT plus AHT. We provide a long-term update after 10 years of follow-up of the primary endpoint (progression-free survival) and report on the late toxicities of treatment.
The trial was designed as a 2 × 2 factorial study with hormonal sequencing as one stratification factor and radiation field as the other factor and tested whether NHT improved progression-free survival versus AHT, and NHT plus WPRT versus NHT plus PORT. Eligible patients had histologically confirmed, clinically localised adenocarcinoma of the prostate, an estimated risk of lymph node involvement of more than 15% and a Karnofsky performance status of more than 70, with no age limitations. Patients were randomly assigned (1:1:1:1) by permuted block randomisation to receive either NHT 2 months before and during WPRT followed by a prostate boost to 70 Gy (NHT plus WPRT group), NHT 2 months before and during PORT to 70 Gy (NHT plus PORT group), WPRT followed by 4 months of AHT (WPRT plus AHT group), or PORT followed by 4 months of AHT (PORT plus AHT group). Hormonal therapy was combined androgen suppression, consisting of goserelin acetate 3·6 mg once a month subcutaneously or leuprolide acetate 7·5 mg once a month intramuscularly, and flutamide 250 mg twice a day orally for 4 months. Randomisation was stratified by T stage, Gleason Score, and prostate-specific antigen concentration. NHT was given 2 months before radiotherapy and was continued until radiotherapy completion; AHT was given at the completion of radiotherapy for 4 months. The primary endpoint progression-free survival was analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00769548. The trial has been terminated to additional follow-up collection and this is the final analysis for this trial.
Between April 1, 1995, and June 1, 1999, 1322 patients were enrolled from 53 centres and randomly assigned to the four treatment groups. With a median follow-up of 8·8 years (IQR 5·07–13·84) for all patients and 14·8 years (7·18–17·4) for living patients (n=346), progression-free survival across all timepoints continued to differ significantly across the four treatment groups (p=0·002). The 10-year estimates of progression-free survival were 28·4% (95% CI 23·3–33·6) in the NHT plus WPRT group, 23·5% (18·7–28·3) in the NHT plus PORT group, 19·4% (14·9–24·0) in the WPRT plus AHT group, and 30·2% (25·0–35·4) in the PORT plus AHT group. Bladder toxicity was the most common grade 3 or worse late toxicity, affecting 18 (6%) of 316 patients in the NHT plus WPRT group, 17 (5%) of 313 in the NHT plus PORT group, 22 (7%) of 317 in the WPRT plus AHT group, and 14 (4%) of 315 in the PORT plus AHT group. Late grade 3 or worse gastrointestinal adverse events occurred in 22 (7%) of 316 patients in the NHT plus WPRT group, five (2%) of 313 in the NHT plus PORT group, ten (3%) of 317 in the WPRT plus AHT group, and seven (2%) of 315 in the PORT plus AHT group.
In this cohort of patients with intermediate-risk and high-risk localised prostate cancer, NHT plus WPRT improved progression-free survival compared with NHT plus PORT and WPRT plus AHT at long-term follow-up albeit increased risk of grade 3 or worse intestinal toxicity. Interactions between radiotherapy and hormonal therapy suggests that WPRT should be avoided without NHT.
National Cancer Institute.
Journal Article
Estrogen therapy in patients with prostate cancer: a contemporary systematic review
by
Zani, Emerson Luis
,
Leonardo Oliveira Reis
,
Herney Andrés García-Perdomo
in
Androgens
,
Clinical trials
,
Flutamide
2018
PurposeTo evaluate the effectiveness and harms of DES in treating prostate cancer compared to other forms of androgen deprivation therapy (orchiectomy, LHRH agonists, and anti-androgens).MethodsWe included clinical trials comparing DES with other forms of ADT (bicalutamide, flutamide, LHRH agonists, or orchiectomy) in PCa treatment. The primary outcomes were overall survival, cancer-specific survival, and progression-free survival, and secondary outcomes were cardiovascular effects. We searched in MEDLINE, EMBASE, Central, and Lilacs from inception to nowadays and saturated information for unpublished data in other sources. We performed a qualitative analysis of all included studies. It was not possible to perform meta-analysis due to low-quality trials and high heterogeneity.ResultsOverall, 1700 references were scanned and 14 prospective randomized trials with a total of 3986 patients were included in the final analysis. Although trials showed DES as similarly effective to another forms of ADT, evidences about cardiovascular toxicity in out of date high doses have discouraged its use. In doses of 1 mg, DES has been used as secondary line PCa treatment with safety.ConclusionsDES might be similarly effective to other forms of ADT on advanced PCa patients, with potential important roles. Intriguingly, the burden of severe cardiovascular toxicity is mainly related to old-fashioned doses of 5.0 and 3.0 mg. Modern PCa hormonal knowledge warrants stout high-quality prospective randomized trials in the low-dose 1 mg DES scenario.
Journal Article
Pathogenesis and molecular targeted therapy of spinal and bulbar muscular atrophy (SBMA)
by
Banno, Haruhiko
,
Sobue, Gen
,
Katsuno, Masahisa
in
Analysis
,
androgen receptors
,
animal models
2012
Spinal and bulbar muscular atrophy (SBMA), also known as Kennedy’s disease, is an adult-onset, X-linked motor neuron disease characterized by muscle atrophy, weakness, contraction fasciculations, and bulbar involvement. SBMA is caused by the expansion of a CAG triplet repeat, encoding a polyglutamine tract within the first exon of the androgen receptor (AR) gene. The histopathological finding in SBMA is the loss of lower motor neurons in the anterior horn of the spinal cord as well as in the brainstem motor nuclei. There is no established disease-modifying therapy for SBMA. Animal studies have revealed that the pathogenesis of SBMA depends on the level of serum testosterone, and that androgen deprivation mitigates neurodegeneration through inhibition of nuclear accumulation and/or stabilization of the pathogenic AR. Heat shock proteins, the ubiquitin–proteasome system and transcriptional regulation are also potential targets for development of therapy for SBMA. Among these therapeutic approaches, the luteinizing hormone-releasing hormone analogue, leuprorelin, prevents nuclear translocation of aberrant AR proteins, resulting in a significant improvement of disease phenotype in a mouse model of SBMA. In a phase 2 clinical trial of leuprorelin, the patients treated with this drug exhibited decreased mutant AR accumulation in scrotal skin biopsy. Phase 3 clinical trial showed the possibility that leuprorelin treatment is associated with improved swallowing function particularly in patients with a disease duration less than 10 years. These observations suggest that pharmacological inhibition of the toxic accumulation of mutant AR is a potential therapy for SBMA.
Journal Article
GNRH agonists and antagonists in rescue for cyclophosphamide-induced ovarian damage: friend or foe?
by
Kilicdag, Esra B.
,
Haydardedeoglu, Bulent
,
Parlakgumus, Alper
in
Animals
,
Cyclophosphamide - toxicity
,
Endocrinology
2015
Purpose
To find out if GnRH agonist (GnRHa) and GnRH antagonist (GnRHant) offer ovarian protection from cyclophosphamide (Cyc) and if AMH expression is affected.
Methods
This experimental study was conducted in Baskent University Animal research laboratory and 66 virgin Wistar albino rats were assigned to six groups. The control group received intraperitoneal saline injection. The GnRHa group had a single dose of leuprolide acetate (1 mg/kg) 28 days prior to saline injection. The GnRHant group had a single dose of cetrorelix acetate (0.1 mg/kg) 1 h prior to saline injection. The Cyc group had a single intraperitoneal dose of Cyc (75 mg/kg). The GnRHa+Cyc group had a single dose of leuprolide acetate (1 mg/kg) 28 days prior to Cyc (75 mg/kg). The GnRHant+Cyc group had single dose of cetrorelix acetate (0.1 mg/kg) 1 h prior to Cyc (75 mg/kg). At day 35, the animals were euthanized, and their ovaries were removed. Primordial follicles were counted and AMH expression was determined. The Kruskal–Wallis,
χ
2
, or Fisher’s exact test was used where appropriate.
p
< 0.05 was considered statistically significant.
Results
PMF count was reduced in GnRHant (
p
< 0.01) and Cyc (
p
< 0.01) groups. Cyc, GnRHa+Cyc and GnRHant+Cyc groups had similar numbers of PMF. AMH expression was reduced in Cyc, GnRHa+Cyc and GnRHant+Cyc groups (
p
< 0.01).
Conclusion
Neither GnRHa nor GnRHant can offer protection against Cyc-induced damage. GnRHant itself reduces the number of primordial follicles.
Journal Article
Sex Hormone Dependency of Diethylnitrosamine‐induced Liver Tumors in Mice and Chemoprevention by Leuprorelin
by
Ito, Akihiro
,
Fujimoto, Nariaki
,
Roy, Goutam
in
Antiestrogens
,
Body weight
,
Bromodeoxyuridine
2001
The prevalence of liver tumors throughout the world makes it imperative to seek chemopreventive agents. This tumor appears to be hormone‐responsive and hormonal manipulations may therefore be beneficial. On this basis, both sexes of 12‐day‐old B6C3FJ mice were injected i.p. with diethylnitrosamine (DEN) at the dose of 2.5 μg/g body weight and observed for 32 weeks (males) or 36 weeks (females). In 100% of male mice, liver tumors were observed with an average diameter of 2.72 mm and multiplicity of 60.8. Orchidectomy at 6 weeks of age in these mice inhibited the incidence, multiplicity and size to 63%, 5.6 and 1.54 mm, respectively. By further implantation with an E2 pellet at monthly intervals, these parameters were reduced to 26%, 0.6 and 0.61 mm, respectively. Administration of a gonadotropin‐blocking chemical, leuprorelin, to DEN‐treated male mice significantly reduced the multiplicity and size of tumors to 18.3 and 2.54 mm (P<0.01 compared to those of DEN only). In female mice, the incidence of liver tumor was significantly smaller than that of males. However, ovariectomy and/or testosterone supplement significantly increased the occurrence of liver tumor. An anti‐estrogen, toremifene, caused a marked further decrease of liver tumors. Mitotic indices with bromodeoxyuridine in tumor tissues paralleled the occurrence of liver tumors. Serum testosterone levels were significantly reduced by orchidectomy or by leuprorelin administration. These results further confirm that liver tumor is testosterone‐responsive and hormonal manipulation by surgical orchidectomy or by chemical orchidectomy i.e. by leuprorelin, could substantially prevent the appearance of liver tumors.
Journal Article
In-vitro/In-vivo comparison of leuprolide acetate release from an in-situ forming plga system
2013
A poly (lactide-co-glycolide) (PLGA) implant was used to control the release profile of leuprolide acetate (LA) drug. The system is an in-situ polymeric precipitation system. And the formulation consisted of PLGA polymer, LA drug and N-methyl-2-pyrrolidon solvent with no additives. First, the formulation was injected into PBS solution for in-vitro studies and then it was administered to the animal models (female rats) for in-vivo release studies. The release profiles of leuprolide acetate were measured by UV spectrophotometry for a period of 28 days. The initial burst release of LA was 14% in in-vitro whereas it was 7% in in-vivo. In-vitro and in-vivo release profiles of LA had similar trends after 72 hours. However, the rate of LA release was slower in-vivo. This might be attributed to the limited diffusion process of solvent and the drug molecules. This could be due to presence of an additional pressure caused by the surrounding tissue and also the presence of small amount of water between cells in the subcutaneous site. Cross-section and surface of the implants were studied via scanning electron microscopy. Morphology of both in-vitro and in-vivo implants confirmed the release behaviours. No toxicity effects were reported in the histopathological assay. Furthermore, the pharmacological analysis showed more inactive ovaries due to release of LA.
Journal Article
Slipped capital femoral epiphyses associated with the withdrawal of a gonadotrophin releasing hormone
by
van Puijenbroek, Eugène
,
de Graaf, Linda
,
Verhoef, Emil
in
Child
,
Epiphyses, Slipped - chemically induced
,
Female
2004
The assumption had been that during treatment with a GnRH agonist low oestrogen concentrations decrease epiphyseal activity and weaken the epiphyseal plate. 1 The increase in growth velocity after stopping GnRH agonist, subsequently results in a reduction of the shearing force needed for the displacement of the epiphysis. 1 A similar mechanism may be involved in children treated with growth hormone, who were more likely to develop slipped capital femoral epiphyses than children with idiopathic short stature who were not treated. 3 We suggest that cessation of GnRH agonists be added to the list of known risk factors for slipped capital femoral epiphysis.
Journal Article
Impact of hormone therapy on acute radiotherapy toxicity in the treatment of prostate cancer
by
Gratzle, J
,
Jani, A B
,
Myers, M
in
Aged
,
Anilides - therapeutic use
,
Antineoplastic Agents - therapeutic use
2005
Purpose: To analyze the impact of neoadjuvant hormone therapy (HT) on acute gastrointestinal (GI) and genitourinary (GU) toxicity from radiotherapy (RT).
Scope: The toxicity rates of 480 consecutive prostate cancer patients were reviewed and compared using the
χ
2
test. Ordered logit regression analyses were performed including the major demographic, disease, and treatment factors. Although no reduction in acute GI toxicity from HT use was observed (
P
=0.067), a lower rate of acute GU toxicity was observed (
P
=0.002). No factor reached statistical significance on regression analysis.
Conclusions: Observed toxicity rates were similar or lower in patients receiving HT. Thus, increased RT toxicity should not be a concern when deciding to add neoadjuvant HT to RT for prostate cancer.
Journal Article