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PubMed1990

Melengestrol acetate and megestrol acetate are prostatic tumor inhibiting agents.

We had previously reported that 6-methylene progesterone, an inhibitor of 5 alpha-reductase, the enzyme which converts testosterone to dihydrotestosterone, markedly inhibited growth of the androgen-dependent Dunning R3327-H rat prostatic tumors. We now find that the progesterone derivatives melengestrol acetate (MGA) and megestrol acetate (MA) inhibit both the androgen-dependent (Dunning R3327-H) and the androgen-independent (Dunning R3327-AT3) prostatic tumors. Growth of the AT3 tumors was suppressed by approximately 53% after 9 days of daily s.c. injections with MGA at 10 mg/kg body weight. MGA also caused a 54% weight reduction of the ventral prostate and a 53% reduction of the seminal vesicles. Adrenal weights were reduced by 42%. A 24-day oral treatment with MGA (at approximately 15-17 mg/(kg.day)) inhibited AT3 tumor growth by 59% and caused a weight reduction in the following tissues: prostate (46%), seminal vesicles (19%), testes (12%), and adrenals (52%). Under the same protocol, MA inhibited AT3 tumor growth by 32% and reduced the weight of the ventral prostate by 49% and the weight of the adrenals by 18%, but had no effect on the seminal vesicles and testes. The extent of the MGA-induced prostatic regression was accompanied by cytological changes similar to those effected by 6-methylene progesterone, i.e., shrinking of the acinar epithelium. The AT3 tumors in MGA-treated rats displayed a limited degree of apoptosis. Atrophy of the adrenal cortex and lowered plasma levels of corticosterone and dihydroepiandrosterone were also observed. A therapeutic role for MGA and MA against androgen-independent prostatic neoplasms in man is forecast by these observations.

Adrenal Glands↗

PubMed1992

A double-blind placebo controlled trial of medroxyprogesterone acetate and cyproterone acetate with seven pedophiles.

Seven of ten pedophiles in hospital completed a double-blind, placebo-controlled two-dose comparison of medroxyprogesterone acetate and cyproterone acetate. Sequential measures during the 28 week study were: patient self-reports, nurses' observations, phallometry, hormone levels and side-effects. The drugs, which performed equivalently, reduced sexual thoughts and fantasies, the frequency of early morning erections on awakening, the frequency and pleasure of masturbation, and level of sexual frustration. Penile responses were also reduced but to a lesser degree and were more variable. Serum testosterone FSH and LH all declined during drug administration, but by the end of the final placebo phase had essentially returned to (or exceeded) pre-drug values. Our experience suggests that only a minority of pedophiles are likely to accept libido-reducing drugs.

Adult↗

PubMed2001

The fate of trenbolone acetate and melengestrol acetate after application as growth promoters in cattle: environmental studies.

The steroids trenbolone acetate (TbA) and melengestrol acetate (MGA) are licensed as growth promoters for farm animals in several meat-exporting countries. Although many studies have explored their safety for both animals and consumers, little is known about their fate after excretion by the animal. Our study aimed to determine the residues and degradation of trenbolone and MGA in solid dung, liquid manure, and soil. In animal experiments lasting 8 weeks, cattle were treated with TbA and MGA. Solid dung and, in case of trenbolone, liquid manure were collected and spread on maize fields after 4.5 and 5.5 months of storage, respectively. Determination of the hormone residues in all samples included extraction, clean-up (solid-phase extraction), separation of metabolites and interfering substances by HPLC (RP-18), and quantification by sensitive enzyme immunoassay. Procedures were validated by mass spectrometry (MS) methods. During storage of liquid manure the level of trenbolone decreased from 1,700 to 1,100 pg/g (17alpha-isomer), corresponding to a half-life of 267 days. Before storage, the concentrations in the dung hill ranged from 5 to 75 ng/g TbOH and from 0.3 to 8 ng/g MGA. After storage, levels up to 10 ng/g trenbolone, and 6 ng/g MGA were detected. In the soil samples trenbolone was traceable up to 8 weeks after fertilization, and MGA was detected even until the end of the cultivation period. The results show that these substances should be investigated further concerning their potential endocrine-disrupting activity in agricultural ecosystems.

Agriculture↗

PubMed1998

Cytokine involvement in cancer anorexia/cachexia: role of megestrol acetate and medroxyprogesterone acetate on cytokine downregulation and improvement of clinical symptoms.

The characteristic clinical picture of anorexia, tissue wasting, loss of body weight accompanied by a decrease in muscle mass and adipose tissue, and poor performance status that often precedes death has been named the cancer-related anorexia/cachexia syndrome (CACS). Chronic administration of pro-inflammatory cytokines, including interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF) either alone or in combination, is capable of reproducing the different features of CACS. High serum levels of these cytokines have been found in cancer patients, which seem to correlate with progression of the tumor. This paper describes a series of experimental and clinical studies demonstrating that: (1) high serum levels of some cytokines, including IL-1, IL-6, and TNF, are present in advanced-stage cancer patients, particularly those with CACS; (2) megestrol acetate (MA) has a beneficial therapeutic effect on CACS symptoms, such as appetite, body weight, and quality-of-life; (3) MA downregulates the synthesis and release of cytokines and relieves the symptoms of CACS; (4) cytokines play a key role in the onset of CACS; (5) medroxyprogesterone acetate (MPA) reduces the in vitro production of cytokines and serotonin (5-hydroxytryptamine, 5-HT) by peripheral blood mononuclear cells (PBMC) of cancer patients; and (6) MA and MPA reduce the cisplatin-induced 5-HT release in vitro from PBMC of cancer patients. Based on these results, a clinical study incorporating MA/MPA in combination with chemotherapy or chemoimmunotherapy may be warranted.

Anorexia↗

PubMed1997

Serum concentrations of trenbolone-17 beta and estradiol-17 beta and performance of heifers treated with trenbolone acetate, melengestrol acetate, or estradiol-17 beta.

The effects of the growth-promoting steroids estradiol-17 beta (E2), trenbolone acetate (TBA), and melengestrol acetate (MGA) in heifers on serum concentrations of E2 and trenbolone-17 beta (TBOH) were examined. Feed intake and growth performance were also measured. Serum concentrations of E2 and TBOH were measured on d 0, 1, 3, 5, 7, 13, 21, 28, 42, 56, 84, 112, and 140 in finishing heifers administered the following treatments: 1) control; 2) MGA, .5 mg per heifer daily; 3) Revalor-H (140 mg TBA + 14 mg E2); 4) Revalor-H + MGA; 5) Finaplix-H (200 mg TBA); and 6) Finaplix-H + MGA. Revalor-H implantation (Treatments 3 and 4) increased (P < .05) serum E2 concentrations; peak concentrations (67.5 pg/mL) occurred between d 21 and 56. Feeding MGA (Treatment 4) had no effect (P > .05) on this increase in serum E2 concentrations (63.3 pg/mL). From d 84 until d 140, serum E2 was greater (P < .05) for the Revalor-H treatment (average of 19 pg/mL) than for the control (7 pg/mL) or Finaplix-H treatments (6.5 pg/mL). Serum E2 concentrations increased numerically two- to threefold from d 56 to 140 in controls fed MGA, compared with controls not fed MGA. There was the expected increase in serum TBOH concentrations after TBA implantation in the Revalor-H and Finaplix-H treatments; concentrations were similar (P > .05) for Revalor-H (221 pg/mL) and Finaplix-H (280 pg/mL). After d 56, serum TBOH concentrations decreased in both treatments to 10 and 20% of these concentrations, respectively. Feeding MGA increased serum TBOH (P < .05). Dry matter intake by heifers did not differ among treatments. Feeding of MGA improved gains (P = .12) and efficiencies (P < .01) in nonimplanted heifers and had no effect (P > .4) on gains or efficiencies in Finaplix-implanted heifers.

Anabolic Agents↗

PubMedDate not supplied

Medroxyprogesterone acetate and megestrol acetate reduce cisplatin-induced serotonin release from human peripheral blood mononuclear cells of cancer patients.

In the present study we evaluated the ability of either medroxyprogesterone acetate (MPA) or megestrol acetate (MA) to reduce cisplatin (CDDP)-induced serotonin (5-HT) release from peripheral blood mononuclear cells (PBMC) of cancer patients. Sixteen patients with cancer of different sites, all in advanced stage of disease, were studied (10 for MPA and 6 for MA). The levels of 5-HT in culture supernatants of PBMC stimulated with CDDP were higher than controls (100 nM vs 51 for MPA study and 123 vs 64 for MA study) and were in the same range of PHA-stimulated PBMC. The addition into cultures of MPA or MA was able to significantly reduce the CDDP-induced production of 5-HT (62 nM for MPA, and 46 for MA study). MPA as well as MA are able to inhibit 5-HT production and/or release by CDDP-stimulated PBMC of cancer patients: this finding to our knowledge has not been previously reported. The concentrations of MPA and MA used in cultures were in the same range as those raised in plasma following the clinical administration of daily doses of 1,000/2,000 mg of MPA and 320 to 960 mg of MA.

Aged↗

PubMed1990

Lithium acetate gastrointestinal diffusion system. Part 1: Lithium acetate single-unit gastrointestinal diffusion system: preparation and release rate studies.

The gastrointestinal diffusion system (GDS), containing lithium acetate (1), releases the drug by a controlled source of diffusion energy. The unit can possibly be used for all soluble drugs in which solubility is independent from the pH of the gastrointestinal contents as is the case with 1. The one-compartment unit is obtained by tabletting the drug and coating the tablets with a membrane of cellulose acetate to which soluble porofores-gum arabic, sodium chloride, 1-are added. When the pore-creating substance is dissolved out of the coating, there remains a porous film, which controls the rate of release of the drug. The release characteristics depend on membrane composition and mass. The systems reported here provided for zero-order drug delivery in vitro.

Acetates↗

PubMed1981

Antiandrogenic effects of cyproterone acetate and chloromadinone acetate on the rat hypothalamus as revealed by electroencephalographic responses.

Bipolar stainless steel electrodes were implanted stereotaxically into given hypothalamic and cortical regions of the brain of 48 rats. The animals were divided into two groups of equal numbers and the electrical activity of the given regions was recorded electroencephalographically (EEG). The effect of the acute and chronic administration of cyproterone acetate (CPA) or chloromadinone acetate (CHA), in doses inducing sterility, on EEG activity were observed. Apart from slight inhibition in the preoptic region, no appreciable EEG changes were found after CPA, while CHA reduced the discharge frequency in both the preoptic and the posterior hypothalamus. These findings can be attributed to the presence of two different types of androgen receptors in the hypothalamus.

Androgen Antagonists↗

PubMed1981

Effects of hexestrol, medroxyprogesterone acetate and chlormadinone acetate on 7, 12-dimethylbenz [a] anthracene-induced rat mammary cancer in relation to estrogen receptor.

The effects of hexestrol (HXS), medroxyprogesterone acetate (MAP) and chlormadinone acetate (CMA) on 7, 12-dimethylbenz [a] anthracene-induced mammary cancer in rats were evaluated. As a result of successive intramuscular injections of HXS at dosages of 2 or 10 mg/kg or MAP at dosages of 24 or 120 mg/Kg, tumors were markedly reduced in size in all groups on day 7 approximately 14. These effects were the same regardless of the presence or absence of cytoplasmic estrogen receptors (ER) in tumors as determined by the dextran-coated charcoal method. Although such an effect was also seen with CMA, it was much less marked than the effects seen with HXS and MAP. The body weights of HXS-administered groups decreased considerably, whereas those of MAP-administered groups increased. These results may suggest that there is another endocrinological tumor-suppressing mechanism besides the mechanism involving the estrogen-ER system in large-dose administration of HXS and MAP.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1998

Cytokine activity in cancer-related anorexia/cachexia: role of megestrol acetate and medroxyprogesterone acetate.

The characteristic clinical picture of anorexia, tissue wasting, loss of body weight accompanied by a decrease in muscle mass and adipose tissue, and poor performance status that often precedes death has been named the cancer-related anorexia/cachexia syndrome (CACS). Chronic administration of pro-inflammatory cytokines, including interleukin-I (IL-I), IL-6, and tumor necrosis factor (TNF), either alone or in combination, is capable of reproducing the different features of CACS. High serum levels of these cytokines have been found in cancer patients, which seem to correlate with progression of the tumor. This article describes a series of experimental and clinical studies demonstrating that: (1) high serum levels of some cytokines, including IL-I, IL-6, and TNF, are present in advanced-stage cancer patients, particularly those with CACS; (2) megestrol acetate (MA) has a beneficial therapeutic effect on CACS symptoms, such as appetite, body weight, and quality of life; (3) MA downregulates the synthesis and release of cytokines and relieves the symptoms of CACS; (4) cytokines play a key role in the onset of CACS; (5) medroxyprogesterone acetate (MPA) reduces the in vitro production of cytokines and serotonin (5-hydroxytryptamine, 5-HT) by peripheral blood mononuclear cells (PBMC) of cancer patients; and (6) MA and MPA reduce the cisplatin-induced 5-HT release in vitro from PBMC of cancer patients. Based on these results, a clinical study incorporating MA/MPA in combination with chemotherapy or chemoimmunotherapy may be warranted. In addition, it has been recently shown that "oxidative stress" resulting from reactive oxygen species, which can be induced by pro-inflammatory cytokines, is involved in tissue wasting and CACS. These results suggest promising approaches for the prevention and treatment of cytokine-induced CACS based on MA, MPA, and metabolic antioxidants.

Anorexia↗

PubMed1984

Intravaginal controlled administration of flurogestone acetate II: Development of an in vitro system for studying the intravaginal release and permeation of flurogestone acetate.

A relatively simple and easily constructed in vitro system was developed for studying the mechanism of release and intravaginal absorption of flurogestone acetate from vaginal sponges. The stability-indicating high-performance liquid chromatographic method developed earlier was used to provide a rapid, reproducible, and sensitive assay. The in vitro intravaginal release/permeation system developed was capable of determining the rate of flurogestone acetate release from vaginal sponges and, simultaneously, the rate of absorption through the vaginal wall. The design, calibration, and applicability of the system, and the release and absorption profiles of the drug from vaginal sponges in this system are discussed.

Absorption↗

PubMed1990

Influence of aminoglutethimide on the metabolism of medroxyprogesterone acetate and megestrol acetate in postmenopausal patients with advanced breast cancer.

In this study the influence of amino-glutethimide (AG) on the disposition of medroxyprogesterone acetate (MPA) and megestrol acetate (MA) was studied. When 1,000 mg AG daily was supplementally given to six patients on chronic treatment with MPA (1,000 mg/day) or MA (160 mg/day), mean serum levels of progestin were reduced by 74% as compared with control levels (P less than 0.03). AG did not change the blood clearance rate of MPA when the latter was given i.v. This discrepancy between AG's influence on oral and parenteral progestin disposition could be explained by pharmacokinetic properties of the progestins, and our results suggest that AG stimulates the metabolism of progestins. The decrease in MPA and MA serum levels was accompanied by an increase in serum cortisol, sex hormone-binding globulin (SHBG) and testosterone levels. This suggests that AG reduces the biological activity of progestins.

Administration, Oral↗

PubMed1995

Comparison of fresh versus sodium acetate acetic acid formalin preserved stool specimens for diagnosis of intestinal protozoal infections.

The use of sodium acetate acetic acid formalin (SAF)-preserved stool specimens was compared with that of nonpreserved specimens for the recovery of intestinal protozoa. A total of 247 patients, 170 with diarrhea of more than one week's duration and 77 refugees, were asked to collect a stool specimen. Each specimen was placed into two vials, one empty, the other containing SAF fixative. Laboratory investigations included microscopic examination of the concentrated sediment and direct wet smears from both types of stool specimens and the microscopic examination of a permanent stained smear from the unsedimented, SAF-preserved stool specimens. Examination of SAF-preserved stool specimens revealed intestinal protozoa in 149 of the 247 patients. With the conventional procedure using unpreserved stool specimens, intestinal protozoa were found in 89 of the 247 patients. The results show that the examination of SAF-preserved stool specimens, consisting of the microscopic examination of both the concentrated sediment and the permanent stained smear from the unsedimented material, increases the chance of recovering intestinal protozoa as compared to the conventional procedure.

Acetates↗

PubMed1997

The addition of norethindrone acetate to leuprolide acetate for ovarian suppression has no adverse effect on ovarian stimulation.

PURPOSE: Our goal was to determine if the addition of norethindrone acetate (NETA) to leuprolide acetate (LA) has an adverse effect on controlled ovarian stimulation (COH) during in vitro fertilization (IVF). METHODS: Forty-one consecutive patients undergoing COH and IVF were divided into two groups and evaluated. Group 1 consisted of 18 patients who did not become pregnant following two cycles (one of each protocol). Group 2 consisted of 23 patients who became clinically pregnant following one cycle from either protocol. The standard protocol consisted of LA (1 mg) injected subcutaneously from the first day of menses until day 8 or when ovarian suppression was evident, at which time the dose was halved and COH was initiated. The study protocol was identical except 10 mg of NETA was given orally with LA for the first 8 days. Ovarian stimulation was similar in each protocol. RESULTS: No adverse effect on ovarian stimulation was evident on the addition of NETA to LA. No differences were noted in days of stimulation, peak estradiol (E2) level attained, peak E2-to-oocyte ratio, dosage of exogenous gonadotropins, number of aspirated oocytes, fertilization rate, or oocyte and preembryo quality. CONCLUSIONS: The addition of NETA does not attenuate COH in women undergoing IVF.

Adult↗

PubMed1984

Heat durability of Epstein-Barr virus-activating substances of plant origin: 12-O-tetradecanoylphorbol-13-acetate, 12-O-hexadecanoyl-16-hydrophorbol-13-acetate, croton oil, tung oil and Croton megalocarpus extract.

12-O-Tetradecanoyl-phorbol-13-acetate (TPA), 12-O-hexadecanoyl-16-hydrophorbol-13-acetate (HHPA), croton oil, tung oil and Croton megalocarpus ether extract, all of which are known to possess Epstein-Barr virus-activating potency, retained their capacity to induce Epstein-Barr virus early antigen complex in the viral genome-carrying human lymphoblastoid cells (Raji) even after heat treatment at 120 degrees C for 2 h or at 100 degrees C for 12 h. Such unusual heat resistance of the agents tested may contribute to the persistence and accumulation of the active principle(s) in soil under the plants which contain such substances, as we have previously reported.

Antigens, Viral↗

PubMed1985

15-Hydroxycyproterone acetate and cyproterone acetate levels in plasma and urine.

15 beta-Hydroxycyproterone acetate (15HOCPA) and cyproterone acetate (CPA) have been quantitated in human plasma and urine by a selective high-performance liquid chromatographic assay. The levels of 15HOCPA in plasma are generally twice those of its precursor CPA, although both compounds appear to have similar clearance rates. Approximately 6% of the dose is excreted into the urine, predominantly (greater than 90%) as the free form of 15HOCPA and CPA.

Chromatography, High Pressure Liquid↗

PubMed2004

Serum medroxyprogesterone acetate levels in new and repeat users of depot medroxyprogesterone acetate at the end of the dosing interval.

In the absence of published data on serum medroxyprogesterone acetate (MPA) levels in South African users, this study examines such levels in new and repeat users of depot medroxyprogesterone acetate at the end of the dosing interval. The study was undertaken at three family-planning clinics in Durban, South Africa. Serum MPA levels were measured in 94 Black African, Indian and White women returning between 11 and 14 weeks after their last injection. The median serum MPA level was 0.88 (range, <0.04-1.77) ng/mL and wide interindividual variability was observed. Levels in all but one woman were higher than 0.1 ng/mL, the level at which ovulation is reported to resume. MPA levels were not found to vary according to weight, body mass index or ethnicity. Although there was a slight tendency towards higher MPA levels with longer duration of use (r = 0.13), the wide interindividual variability precluded the possibility of determining whether this was a real trend. A prospective study, using standardized assay techniques and following individual women, is required to further clarify this issue.

Adolescent↗

PubMed2001

Reactivity of some sugars and sugar phosphates towards gold(III) in sodium acetate-acetic acid buffer medium.

The kinetics of the oxidation of some aldoses and aldose phosphates have been studied spectrophotometrically in sodium acetate-acetic acid buffer medium at different temperatures. The reactions are first order with respect to [Au(III)] and [substrate]. Both H+ and Cl- ions retard the reaction. The reactions appear to involve different gold(III) species, viz. AuCl4-, AuCl3(OH2) and AuCl3(OH)- . The results are interpreted in terms of the probable intermediate formation of free radicals and Au(II). Aldoses react with gold(III) in the order: triose > tetrose > pentose > hexose. The sugar phosphates react with gold(III) at a faster rate than the parent sugars except glucose-1-phosphate, which reacts at slower rates than glucose. A tentative reaction mechanism leading to the formation of products has been suggested.

Aldehydes↗