Potentiation of Ecstasy-induced hyperthermia and FAT/CD36 expression in chronically exercised animals.

Fatal hyperthermia as a result of 3,4-methylenedioxymethamphetamine (MDMA) use involves non-esterified free fatty acids (NEFA) and the activation of mitochondrial uncoupling proteins (UCP). NEFA gain access into skeletal muscle via specific transport proteins, including fatty acid translocase (FAT/CD36). FAT/CD36 expression is known to increase following chronic exercise. Previous studies have demonstrated the essential role of NEFA and UCP3 in MDMA-induced hyperthermia. The aims of the present study were to use a chronic exercise model (swimming for two consecutive hours per day, five days per wk for six wk) to increase FAT/CD36 expression in order to: 1) determine the contribution of FAT/CD36 in MDMA (20 mg/kg, s.c.)-mediated hyperthermia; and 2) examine the effects of the FAT/CD36 inhibitor, SSO (sulfo-N-succinimidyl oleate), on MDMA-induced hyperthermia in chronic exercise and sedentary control rats. MDMA administration resulted in hyperthermia in both sedentary and chronic exercise animals. However, MDMA-induced hyperthermia was significantly potentiated in the chronic exercise animals compared to sedentary animals. Additionally, chronic exercise significantly reduced body weight, increased FAT/CD36 protein expression levels and reduced plasma NEFA levels. The FAT/CD36 inhibitor, SSO (40 mg/kg, ip), significantly attenuated the hyperthermia mediated by MDMA in chronic exercised but not sedentary animals. Plasma NEFA levels were elevated in sedentary and exercised animals treated with SSO prior to MDMA suggesting attenuation of NEFA uptake into skeletal muscle. Chronic exercise did not alter skeletal muscle UCP3 protein expression levels. In conclusion, chronic exercise potentiates MDMA-mediated hyperthermia in a FAT/CD36 dependent fashion.

Oral modified-release tranexamic acid for heavy menstrual bleeding.

OBJECTIVE: To review the pharmacology, pharmacokinetics, efficacy, and safety profile of an oral modified-release (MR) formulation of tranexamic acid. DATA SOURCES: Literature was accessed through MEDLINE (1966-July 2012), Iowa Drug Information Service (1997-July 2012), and bibliographies of pertinent articles. Search terms included tranexamic acid, Lysteda, menorrhagia, menstrual blood loss, and heavy menstrual bleeding. STUDY SELECTION AND DATA EXTRACTION: All available English-language abstracts and human studies were identified for review. Data provided by the manufacturer and the Food and Drug Administration were also evaluated. Efficacy was evaluated in 2 clinical trials, change in quality of life was evaluated in 3 clinical trials, and safety was evaluated in 4 clinical trials. DATA SYNTHESIS: Tranexamic acid is a synthetic lysine analogue with antifibrinolytic activity. It interferes with the binding of plasminogen to fibrin, resulting in enhanced fibrin clot integrity. A novel MR formulation of oral tranexamic acid is approved for treatment of cyclic heavy menstrual bleeding. MR tranexamic acid is initiated at the beginning of heavy menstrual bleeding and can be taken for up to 5 days per cycle. Clinical trials show it to be safe and effective. Dosage adjustments are needed for women with renal insufficiency. Adverse effects are considered mild to moderate, with the most common being menstrual discomfort, headache, and back pain. The most significant safety concerns relate to the risk of thromboembolism. CONCLUSIONS: MR tranexamic acid offers a new first-line therapy for patients with cyclic heavy menstrual bleeding. It is reported to be safe and effective. There are no labeled equivalents to MR tranexamic acid for cyclic heavy menstrual bleeding.

Identification of a possible role for atrial natriuretic peptide in MDMA-induced hyperthermia.

MDMA (3,4-methylenedioxymethamphetamine) induces thermogenesis in a mitochondrial uncoupling protein 3-dependent manner. There is evidence that this hyperthermia is mediated in part by the lipolytic release of free fatty acids, that subsequently activate uncoupling protein 3 in skeletal muscle mitochondria. We hypothesize that atrial natriuretic peptide (ANP), a strong lipolytic mediator, may contribute to the induction and maintenance of MDMA-induced thermogenesis. The specific aims of this study were to (1) determine if ANP is released following MDMA administration, and (2) use the ANP receptor antagonist, Anantin, to ascertain the role of ANP in MDMA-induced hyperthermia. ANP levels were measured in plasma at baseline, 10, 20, 30 and 60 min following MDMA (40 mg/kg, sc) administration in 16 male Sprague-Dawley rats. A robust increase in ANP was seen within 10 min of MDMA administration. ANP levels returned to baseline at 20 min and then gradually rose over the 60 min monitoring period. The administration of Anantin (40 mg, ip), 15 min before and after MDMA, significantly attenuated the MDMA-induced hyperthermia. We conclude that ANP signaling contributes to the hyperthermia induced by MDMA.

Review of available infertility treatments.

Treatments for infertility vary in their intensity, invasiveness and associated risks. Treatment can range from medication to induce ovulation to invasive manipulation of eggs and sperm outside of the body. The type of treatment utilized is dependent upon the cause, degree and duration of infertility; the patient's age; the tolerance of side effects; the history of responsiveness and side effects in previous treatments; and the specific treatment preferences of the associated physician and facility. Infertility medications are specifically used for ovulation induction or for controlled ovarian hyperstimulation. In ovulation induction, the goal is to stimulate growth, maturation and ovulation of a single follicle. The single follicle is then fertilized secondary to timed intercourse or artificial insemination, where semen is injected directly into the uterus. Artificial insemination or intrauterine insemination can also be used with either natural or drug-induced ovulation. In controlled ovarian hyperstimulation (COH), multiple follicles are stimulated to grow and mature with medications. COH is necessary for assisted reproductive techniques (ART). The most commonly utilized type of ART is in vitro fertilization. ART are much more complex and invasive than ovulation induction in that they involve techniques to manipulate and fertilize the egg outside of the body. The goal of ART is to cause recruitment and maturation of multiple follicles. After a sufficient number of follicles have grown and matured, they are retrieved and transferred to an incubator for fertilization. The resulting embryos are returned to the uterus for implantation or cryopreserved. Both ovulation induction and ART require medications for the recruitment, development and maturation of eggs. Both techniques utilize similar medications; however, the doses of medication and the specific protocols for their use are varied. This review will discuss the range of available infertility treatments from medications alone to medications in combination with invasive medical procedures. The mechanism of action, side effects, use and effectiveness of the different classes of medications will be discussed. Because there are multiple medications in specific classes, comparisons of their protocols for use, effectiveness and side effect profiles will be detailed. Lastly, new variations of traditional assisted reproductive techniques will be presented.

Role of ambrisentan in the management of pulmonary hypertension.

OBJECTIVE: To review the role of ambrisentan in the treatment of pulmonary arterial hypertension (PAH). DATA SOURCES: Literature was accessed through MEDLINE (1950-June 2008), Iowa Drug Information Service (1966-March 2008), EMBASE (1966-June 2008), bibliographies of pertinent articles, and unpublished data provided by the manufacturer and the Food and Drug Administration (FDA). Search terms included ambrisentan, endothelin antagonist, pulmonary hypertension, and pulmonary arterial hypertension. Due to limited literature available, additional criteria to limit searches were not used. STUDY SELECTION AND DATA EXTRACTION: Abstracts and original preclinical and clinical research reports available in the English language were identified for review. All manufacturer-provided data were also evaluated. Literature related to ambrisentan, endothelin antagonists, pulmonary hypertension, and pulmonary arterial hypertension were included. Four clinical trials evaluated the efficacy of ambrisentan in adults with symptomatic PAH. DATA SYNTHESIS: Ambrisentan is the latest endothelin-receptor antagonist (ERA) to obtain FDA approval for the treatment of PAH. It joins the first FDA-approved ERA, bosentan. Like bosentan, ambrisentan is available orally (with once-daily dosing compared with bosentan's twice-daily dosing) and has been shown to improve exercise capacity and delay clinical worsening. As with bosentan, the most significant safety concerns with ambrisentan relate to potential liver injury and a contraindication in pregnancy. Although ambrisentan has higher affinity for the endothelin type A receptor than for the endothelin type B receptor, specific advantages of this selectivity, in terms of efficacy compared with bosentan, a nonselective agent, have not been demonstrated. CONCLUSIONS: Ambrisentan has been shown to be an effective ERA in patients with PAH. A significant advantage of ambrisentan is the lack of any clinically important drug interactions with warfarin and sildenafil, which are frequently used by patients being treated for PAH.

Use of sildenafil for female sexual dysfunction.

OBJECTIVE: To review the pathophysiology of female sexual dysfunction (FSD) and the literature regarding the use of sildenafil in its treatment. DATA SOURCES: Literature was accessed through MEDLINE (1966-April 2006), Iowa Drug Information Service (1966-April 2006), EMBASE (1966-April 2006), and bibliographies of pertinent articles. Search terms included female sexual dysfunction; sexual dysfunction, psychological; phosphodiesterase inhibitors; and sildenafil. DATA SYNTHESIS: The lack of a clear understanding of FSD contributes to the limited treatment options available. Studies regarding the safety and efficacy of the phosphodiesterase 5 inhibitor sildenafil in the management of FSD were evaluated. Many trials have been of poor quality, making clinical application of their results difficult. The current literature does not show sildenafil to be an effective treatment option for FSD. CONCLUSIONS: Treatment of FSD should include both physical and psychological components. Based on the limited data available, it appears that sildenafil, while well tolerated, offers little or no benefit to most patients with FSD.

Sildenafil citrate for the treatment of pulmonary hypertension.

Pulmonary arterial hypertension is a progressive disease that has a high rate of mortality. For these reasons, early treatment is essential. Treatment choices for pulmonary arterial hypertension are limited by drug tolerability, drug cost and inconvenience associated with administration techniques and dosing schedules. Therefore, a therapy that provides oral dosing with limited side effects would prove useful in managing many patients. Sildenafil citrate, the first and highly publicized oral medication to receive approval from the U.S. Food and Drug Administration for erectile dysfunction, has recently been approved for treatment of pulmonary arterial hypertension. This review summarizes the normal physiology of the pulmonary vasculature, and the pathophysiology involved in pulmonary arterial hypertension and the role of sildenafil in its treatment.

3,4-methylenedioxymethamphetamine (MDMA, ecstasy)-mediated production of hydrogen peroxide in an in vitro model: the role of dopamine, the serotonin-reuptake transporter, and monoamine oxidase-B.

3,4-methylenedioxymethamphetamine (MDMA, ecstasy) has been shown to induce long-term deficits in serotonergic function in animal models. Several studies have suggested that dopamine (DA) uptake into serotonin (5-HT) terminals by the 5-HT reuptake transporter (SERT) and subsequent deamination by monoamine oxidase-B (MAO-B) leads to the formation of hydrogen peroxide and may be major contributors to this serotonergic toxicity. In the present study, when human choriocarcinoma (JAR) cells were exposed to MDMA (1.2 mM) for 6h, followed by treatment with DA (0.1 mM), hydrogen peroxide production increased over a 24 h period, peaking at 420% over baseline and decreasing cell viability by 30%. DA alone increased hydrogen peroxide production 84% over baseline, but did not significantly decrease cell viability. Incubation of MDMA treated cells with the SERT inhibitor, fluoxetine (500 nM) or the MAO-B inhibitor, L-deprenyl (0.1 mM) for 30 min prior to DA, significantly blocked free radical production and cell death. These findings support the hypothesis that the deamination of DA by MAO-B within the serotonergic cell can lead to hydrogen peroxide formation and ultimately cell death.