The role of insulin-sensitizing agents in the treatment of polycystic ovary syndrome

Histoplasmosis Outbreaks in Brazil: Lessons to Learn About Preventing Exposure

Histoplasmosis is considered the most common invasive opportunistic fungal disease in the Americas, with outbreaks and micro-epidemics reported for over 80 years. In Brazil, this disease has been described since 1946, reaching a remarkable incidence in the population, especially during the HIV-AIDS pandemic. In this study, published and unpublished outbreaks and micro-epidemics of histoplasmosis in Brazil were revisited by accessing different database sources and evaluating epidemiological and clinical features. We have found reports spanning 1946-2017, across 10 Brazilian states and with involvement of 370 humans and 2 dogs, and 13 disseminated cases and 3 deaths were reported. Rio de Janeiro had the largest number of outbreaks (n = 20/40; 50%) reported in this study. The majority of outbreaks and micro-epidemics was reported in caves (n = 21/40; 52.5%), followed by reports in abandoned/deactivated sites (n = 6/40; 15%), mines (n = 5/40; 12.5%), chicken coops (n = 4/40; 10%). Histoplasmosis is a serious health issue in Brazil considering the attractive and growing market of ecotourism throughout more than 7000 caves, and all levels of poultry farming activity are important to raise awareness about how dangerous this neglected disease can be and establish ways to decrease exposure to contaminated environmental sources through adequate preventive measures.

Blastomycosis in Mammals

Blastomycosis is a serious fungal disease of dogs, humans, and occasionally other mammals caused by geographically restricted, thermally dimorphic Blastomyces species. Blastomycosis is primarily a canine disease, with approximately ten dogs diagnosed for every human case. Dogs also develop disease more rapidly, thus becoming sentinels for possible human disease. Human and canine blastomycosis may differ according to epidemiology/epizoology, clinical features, performance and use of diagnostics, and management.

Reproductive neuroendocrine dysfunction in polycystic ovary syndrome: insight from animal models

Polycystic ovary syndrome (PCOS) is a common endocrinopathy with elusive origins. A clinically heterogeneous disorder, PCOS is likely to have multiple etiologies comprised of both genetic and environmental factors. Reproductive neuroendocrine dysfunction involving increased frequency and amplitude of gonadotropin-releasing hormone (GnRH) release, as reflected by pulsatile luteinizing hormone (LH) secretion, is an important pathophysiologic component in PCOS. Whether this defect is primary or secondary to other changes in PCOS is unclear, but it contributes significantly to ongoing reproductive dysfunction. This review highlights recent work in animal models, with a particular emphasis on the mouse, demonstrating the ability of pre- and postnatal steroidal and metabolic factors to drive changes in GnRH/LH pulsatility and GnRH neuron function consistent with the observed abnormalities in PCOS. This work has begun to elucidate how a complex interplay of ovarian, metabolic, and neuroendocrine factors culminates in this syndrome.

Metformin-clomiphene citrate vs. clomiphene citrate alone: Polycystic ovarian syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the commonest endocrinopathy in women that is associated with reproductive and metabolic disorders.

OBJECTIVES

We compared the ovulation and conception rates after the treatment with clomiphene citrate (CC) alone and in combination with metformin in infertile patients presented with polycystic ovarian syndrome (PCOS).

MATERIALS AND METHODS

This randomized controlled trial of independent cases and controls was conducted at the Department of Obstetrics and Gynecology, Hera General Hospital, Makkah, Saudi Arabia from February 01 to December 31, 2008. The 42 subjects diagnosed as PCOS were divided into group A and B (21 subjects in each) for management with CC + metformin and CC alone, respectively. Group A received 500 mg three times a day of metformin continuously from the first cycle for 6 months or till pregnancy was confirmed. In both groups CC was started at a dose of 50 mg from day-2 till day-6 of the menstrual cycle. The dose of CC was increased to 100 mg in second and 150 mg in third cycle, and then remained 150 mg for the remaining three cycles. With ovulation the dose of CC was unaltered in both groups. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 16.

RESULTS

More than 50% females in both groups were had body mass index > 25. Group A achieved high rate of regular cycles, ovulation success, and conception than group B (71.4% vs. 38.1%; P = 0.03), (76.2% vs. 38.1%; P = 0.021), and (66.6% vs. 28.6%; P = 0.01), respectively.

CONCLUSION

Management with metformin + CC increased the ovulation and conception rates.

Metabolic and other effects of pioglitazone as an add-on therapy to metformin in the treatment of polycystic ovary syndrome (PCOS)

Insulin resistance is a key pathogenic defect of the clustered metabolic disturbances seen in polycystic ovary syndrome (PCOS). Metformin is an insulin sensitizer acting in the liver and the peripheral tissues that ameliorates the metabolic and reproductive defects in PCOS. In addition, pioglitazone is an insulin sensitizer used in diabetes mellitus type 2 (T2DM), improving insulin resistance (IR) in adipose tissue and muscles. In T2DM, these drugs are also used as a combined treatment due to their "add-on effect" on insulin resistance. Although the beneficial role of troglitazone (a member of the thiazolidinediones (TZDs) family) in PCOS has been shown in the past, currently only pioglitazone is available in the market. A few small randomized controlled trials have directly compared the effectiveness of pioglitazone in women with PCOS, while there are a limited number of small studies that support the beneficial metabolic add-on effect of pioglitazone on metformin-treated PCOS women as compared to metformin or pioglitazone monotherapy. These findings suggest a potentially promising role for combined pioglitazone/metformin treatment in the management of PCOS in metformin-resistant patients. In view of recent concerns regarding pioglitazone usage and its associated health risk, we aim to compare the pros and cons of each drug regarding their metabolic and other hormonal effects in women with PCOS and to explore the possible beneficial effect of combined therapy in certain cases, taking into consideration the teratogenic effect of pioglitazone. Finally, we discuss the need for a randomized controlled trial that will evaluate the metabolic and other hormonal effects of combined metformin/pioglitazone treatment in PCOS with selective treatment targets.

Pleiotropic effects of glitazones: a double edge sword?

Glitazones (thiazolidinediones) are drugs used for diabetes mellitus type 2. By binding to peroxisome proliferator-activated receptor γ (PPARγ) they modulate transcription of genes of carbohydrate and lipid metabolism. Through PPARγ stimulation, however, glitazones also affect other genes, encompassing inflammation, cell growth and differentiation, angiogenesis, which broads their therapeutic potential. The gene expression profile induced by each glitazone shows peculiarities, which may affect its benefit/risk balance; indeed, troglitazone and rosiglitazone have been associated with liver failure and coronary disease, respectively; whether or not these severe adverse effects are solely related to PPARγ remains yet unclear, since glitazones exert also PPARγ-independent effects. Glitazone chemistry serves as scaffold for synthesizing new compounds with PPARγ-independent pharmacological properties and we report here a preliminary observation of inhibition of vasoconstriction by troglitazone in isolated vessels, an effect that appears fast, reversible, and PPARγ-independent. Pleiotropic effects of glitazones need specific attention in terms of drug safety, but also provide basis for drug development and novel experimental therapeutics.

Metformin vs thiazolidinediones for treatment of clinical, hormonal and metabolic characteristics of polycystic ovary syndrome: a meta-analysis

OBJECTIVES

Insulin-sensitizing drugs (ISDs) have been advocated for the long-term treatment of polycystic ovary syndrome (PCOS). It is therefore important to compare the efficacy and safety of ISDs such as metformin and thiazolidinediones (TZDs) for the treatment of this syndrome.

METHODS

A meta-analysis to assess the effectiveness and safety of metformin vs TZDs (including pioglitazone and rosiglitazone) in the treatment of PCOS was conducted, using MEDLINE (1966-May 2010) and EMBASE (1988-May 2010) to select randomized controlled trials comparing clinical, hormonal and metabolic results.

RESULTS

Ten trials were included. TZDs were superior to metformin in reducing serum levels of free testosterone (P=0.03) and dehydroepiandrosterone sulfate (DHEA) (P=0.002) after 3 months treatment. Decreases in triglyceride levels were more pronounced with metformin after 6 months (P<0.0001). Decreases in body mass index (BMI) were greater with metformin treatment as assessed at 3 and 6 months (P<0.00001). There were no significant between-group differences concerning improvements in ovulation, pregnancy rate, menstrual patterns or insulin sensitivity, or changes in serum levels of androstenedione, luteinizing hormone, follicle-stimulating hormone, total cholesterol, low-density lipoprotein C or insulin. Metformin caused a significantly higher incidence of side effects such as nausea, diarrhoea and abdominal cramping (P<0.00001). Significant between-study heterogeneity was detected for several variables assessed.

CONCLUSIONS

The findings from this meta-analysis do not indicate that metformin is superior to TZD's for the treatment of PCOS or vice versa. Between studies, heterogeneity was a major confounder. A large scale, well-designed, randomized, controlled trial is needed to further address this issue.

Insulin-sensitizing agents in the treatment of polycystic ovary syndrome: an update

PURPOSE OF REVIEW

Polycystic ovary syndrome (PCOS) is the most frequent endocrinopathy in reproductive-aged women, mainly characterized by oligoanovulation and hyperandrogenism. Insulin resistance represents a major pathophysiological feature of the syndrome and, therefore, insulin-sensitizing agents (metformin and thiazolidinediones) have been applied in PCOS women. However, the clinical use of insulin sensitizers in PCOS has been debated. The aim of the current review was to update the knowledge regarding the role of metformin and thiazolidinediones in PCOS treatment, focusing on recently published studies.

RECENT FINDINGS

Several clinical trials examined metformin effectiveness on lipids, atherosclerosis and inflammatory markers, hormone levels, menstrual irregularities, ovulation induction, fertility, hirsutism, obesity parameters and quality of life in PCOS women. Metformin treatment was shown to improve these features, although conflicting results were also reported. Only one study investigated pioglitazone effect on PCOS, reporting an improved IVF outcome in clomiphene citrate-resistant PCOS patients. Finally, both metformin and pioglitazone, as a part of a low-dose polytherapy, exerted beneficial effects on lipids, androgen levels, hirsutism and markers of atherosclerosis in nonobese PCOS women.

SUMMARY

Further research, including larger randomized controlled trials and meta-analyses, is needed to clarify the role of metformin and thiazolidinediones in the treatment of clinical and biochemical PCOS characteristics.

Polycystic ovary syndrome in the pediatric population

Polycystic ovary syndrome (PCOS) is a common disorder characterized by hyperandrogenism and disordered gonadotropin secretion, often associated with insulin resistance. The syndrome, which modulates both hormonal and metabolic processes, is the most common endocrinopathy in reproductive-age women and increases a woman's risk of infertility, endometrial pathology, and cardiometabolic disease. As it is currently defined, PCOS most likely encompasses several distinct diseases with similar clinical phenotypes but different underlying pathophysiological processes. However, hyperandrogenism remains the syndrome's clinical hallmark. The clinical manifestations of PCOS often emerge during childhood or in the peripubertal years, suggesting that the syndrome is influenced by fetal programming and/or early postnatal events. However, given that the full clinical spectrum of PCOS does not typically appear until puberty, a "two-hit" hypothesis has been proposed: (1) a girl develops hyperandrogenism via one or more of many different potential mechanisms; (2) the preexisting hyperandrogenism subsequently disturbs the hypothalamic–pituitary–ovarian axis, resulting in ovulatory dysfunction and sustained hyperandrogenism. No consensus guidelines exist regarding the diagnosis and management of PCOS in the pediatric population; however, because the syndrome is a diagnosis of exclusion, the clinical evaluation of girls suspected of having PCOS is aimed at excluding other causes of androgen excess and menstrual dysfunction. For the syndrome's management, emphasis is placed on lifestyle and symptom-directed treatment.

Effects of lifestyle measures, antiobesity agents, and bariatric surgery on serological markers of inflammation in obese patients

Overweight and obesity are highly prevalent in developed countries and are also becoming more frequent in the developing world. Overweight and obese patients have elevated levels of several inflammatory markers and this inflammatory state might contribute to their increased vascular risk. We summarize the effects of lifestyle changes, antiobesity agents, and bariatric surgery on serological inflammatory markers in overweight and obese patients. Most studies showed a decrease in inflammation with all 3 interventions. However, it remains to be established whether the decrease in inflammatory markers induced by lifestyle changes or (where indicated) with antiobesity agents or bariatric surgery will translate into reduced vascular morbidity and mortality in overweight and obese patients.