Marina O Fernández

• MSc, PhD
• Associate Researcher at CONICET at Experimental Medicine and Biology Institute

The UN international legally binding instrument on plastic pollution (UNEA resolution 5/14) aims to reduce plastics pollution. However, midstream and downstream assessments show that optimizing waste management, removal technologies, and improved circularity is not sufficient to curb plastics pollution in the short-, mid- or long-term. Therefore, w...

Plastics are everywhere. They are in many goods that we use every day. However, they are also a source of pollution. In 2022, at the resumed fifth session of the United Nations Environment Assembly, a historic resolution was adopted with the aim of convening an Intergovernmental Negotiating Committee to develop an international legally binding inst...

Disclosure: J.M. Riaño Gómez: None. E. Sorianello: None. V.A. Lux-Lantos: None. N.J. Webster: None. M.O. Fernandez: None. Introduction: Humans and wildlife are exposed to Endocrine Disrupting Chemicals (EDC). Previously, we showed that the in-vitro exposure to Benzophenones 2 and 3 (BP2 and BP3, UV filters) increase cell proliferation in GN11 cells...

Disclosure: L. Domé: None. J.M. Riaño Gomez: None. M.M. Bonaventura: None. M.O. Fernandez: None. A.D. Montaner: None. V.A. Lux-Lantos: None. M.S. Bianchi: None. We have shown that the immunomodulatory oligonucleotide IMT504 (IMT) improves glucose homeostasis in several animal models of type 1 diabetes by regulating immunomodulatory factors and by i...

There is evidence of the existence of an intraovarian gonadotropin-releasing hormone (GnRH) system. There are also reports about the influence of extrinsic ovarian innervation in gonadal function. Therefore, it is interesting to study the relationship between ovarian sympathetic innervation and GnRH to shed light on possible physiological and patho...

Benzophenones (BPs) are endocrine disruptors frequently used in sunscreens and food packaging as UV blockers. Our goal was to assess the effect of benzophenone 2 (BP2) and 3 (BP3) on gene expression related to autophagy process and ER stress response in pancreatic beta cells. To that end, the mouse pancreatic beta cell line MIN6B1 was treated with...

Benzophenones (BP) and Bisphenol A (BPA) are endocrine disrupting chemicals (EDC). Previously, we showed that the in-vitro exposure to EDC inhibited Kiss-induced gene expression in GT1-7 and GN11 cells (donated by Pamela Mellon, UCSD), and altered expression of inflammatory markers in GT1-7 cells and hypothalami of adult male mice.In the present st...

Background Nitric oxide and GnRH are biological factors that participate in the regulation of reproductive functions. To our knowledge, there are no studies that link NO and GnRH in the sympathetic ganglia. Thus, the aim of the present work was to investigate the influence of NO on GnRH release from the coeliac ganglion and its effect on luteal reg...

Bisphenol A (BPA), a monomer of polycarbonate plastics, and Benzophenones (BPs), used as UV-filters, are endocrine disrupting chemicals (EDC) found in everyday products. Previously, we showed that the in-vitro exposure to BPA decreased Kiss-induced GnRH expression in GN11 cells (donated by Dr. Susan Wray, NIH), immature GnRH neurons, and that expos...

The GnRH/GnRH receptor system has been found in several extrapituitary tissues, although its physiological significance has not yet been well established. Taking into account that the peripheral neural system can act as a modulator of pregnancy corpus luteum, the objective was to physiologically investigate the presence of the GnRH system in coelia...

In addition to key mammotrophic hormones such as the pituitary prolactin (PRL) and the ovarian steroids progesterone and estradiol, there are local factors that modulate the tissue dynamics of the mammary glands during pregnancy and lactation. By immunohistochemistry and RT-PCR, we found local transcription and translation of gonadotropin-releasing...

Our laboratory has recently reported gonadotropin-releasing hormone (GnRH) protein expression in mammary gland (MG) epithelial cells of vizcachas during pregnancy and lactation. In addition, we also shown that prolactin (PRL) modulates GnRH MG content. The present work aims to study GnRH gene expression in MG and also, to explore a possible GnRH-au...

Sirt1 is a NAD-dependent class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, evidence suggests that SIRT1 in neurons plays a role in the central regulation of energy balance and reproduction, but no studies have addressed the contribution of astrocytes. We show here...

Bisphenol A, (BPA), a component of polycarbonate plastics, and Benzophenones (BPs), UV filters, are endocrine disrupting chemicals (EDC). Previously we showed that the in vitro exposure to BPA decreased Kiss-induced GnRH expression in GN11 cells (Dr. Susan Wray, NIH), immature GnRH neurons (1). In this study, we analyzed the in vitro effects of BPA...

Sirt1 is a NAD-dependent class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, emerging evidence suggests that neuronal Sirt1 activity plays a role in the central regulation of energy balance and glucose metabolism. In this study we generated mice expressing an enzymat...

Bisphenol A (BPA) is a component of polycarbonate plastics, epoxy resins and polystyrene found in many common products. Several reports revealed potent in vivo and in vitro effects. In this study we analyzed the effects of the exposure to BPA in the hypothalamic-pituitary-thyroid axis in female rats, both in vivo and in vitro. Female Sprague-Dawley...

Mice lacking PPARγ in neurons do not become leptin resistant when placed on a high-fat diet (HFD). In males, this results in a decrease in food intake and an increase in energy expenditure causing reduced body weight, but this difference in body weight is not observed in female mice. In addition, estrous cycles are disturbed and the ovaries present...

PPARγ is expressed in the hypothalamus in areas involved in energy homeostasis and glucose metabolism. In this study, we created a deletion of PPARγ (BKO) in mature neurons in female mice to investigate its involvement in metabolism and reproduction. We observed that there was no difference in age at puberty onset between female BKOs and littermate...

Female obesity is associated with insulin resistance, hyperandrogenemia, and reproductive dysfunction. We hypothesized that elevated free fatty acids (FFAs) might directly modulate pituitary gonadotropin production. FFAs caused a time and dose-dependent increase in phosphorylation of the MAP kinases p38MAPK, JNK1/2 and ERK1/2 in LβT2 gonadotrope ce...

Polycystic ovary syndrome (PCOS) is a major cause of infertility in women and is linked to obesity and insulin resistance. Rosiglitazone, a PPARγ agonist, increases insulin sensitivity and improves PCOS and diabetes. PPARγ ligands have also been found to affect the hypothalamus‐pituitary‐gonadal axis, although their site and mechanism of action are...

Proliferator‐activated receptor gamma (PPARγ) ligands have been used for the treatment of insulin resistance in type 2 diabetes and polycystic ovary syndrome. We created a neuronal‐specific deletion of PPARγ (BKO) by crossing a floxed PPARγ mouse to a Synapsin‐cre mouse and assessed the effect of the gene deletion on reproduction. Male and female B...

Exposure to endocrine disruptors may produce profound alterations in several species. As an example, the neuroendocrine and reproductive alterations due to Bisphenol A in mammals are summarized here.

Gonadotropin synthesis and release is dependent on pulsatile stimulation by the hypothalamic neuropeptide GnRH. Generally, slow GnRH pulses promote FSH production, whereas rapid pulses favor LH, but the molecular mechanism underlying this pulse sensitivity is poorly understood. In this study, we developed and tested a model for FSHβ regulation in m...

We have demonstrated that the administration of delta-iodolactone (i.e., 5-iodo-delta lactone) of arachidonic acid (IL-delta), a mediator in thyroid autoregulation, prevents goiter induction by methylmercaptoimidazol (MMI) in rats. Other studies have shown that transforming growth factor beta-1 (TGF-beta1) mimics some of the actions of excess iodid...

Bisphenol A (BPA), an endocrine disruptor, is a component of polycarbonate plastics, epoxy resins, and polystyrene. Several studies have reported potent in vivo effects, because BPA behaves as an estrogen agonist and/or antagonist and as an androgen and thyroid hormone antagonist. We investigated the effects of neonatal exposure to BPA on the repro...

Bisphenol A (BPA) is a component of polycarbonate plastics, epoxy resins, and polystyrene and is found in many products. Several reports have revealed potent in vivo effects, because BPA acts as an estrogen agonist and/or antagonist and as an androgen and thyroid hormone antagonist. We analyzed the effects of neonatal exposure to BPA on the reprodu...

The second GnRH form, originally identified in chickens (cGnRH-II or GnRH-II), is the most ubiquitous peptide of the GnRH neuropeptide family, being present from jawed fish to human beings. However, the presence of GnRH-II in such an important experimental model as the rat is still an object of discussion. Here we present chromatographic, immunolog...

GnRH has been suggested to participate in corpus luteum function. Here we studied the expression of GnRH mRNA and peptide in two models of rat luteinized tissues: ovarian cells from PMSG-hCG treated prepubertal rats (SPO) and from intrasplenic ovarian tumors (Luteoma). A GnRH autoregulatory effect was evaluated as well as its action on cell prolife...

Previous results showed that GnRH signaling is altered in cells from rat luteinized ovarian tumors (tumor group) because it did not activate the phospholipase C pathway, in contrast to control ovarian cells from superovulated prepubertal rats (SPO). In the present work, alternate GnRH-induced second messengers such as phospholipase A(2) and phospho...