Gestational Exposure to Low Dose Bisphenol A Alters Social Behavior in Juvenile Mice

Bisphenol A (BPA) is a man-made compound used to make polycarbonate plastics and epoxy resins; public health concerns have been fueled by findings that BPA exposure can reduce sex differences in brain and some behaviors. We asked if a low BPA dose, within the range measured in humans, ingested during pregnancy, would affect social behaviors in prepubertal mice. We noted sex differences in social interactions whereby females spent more time sitting side-by-side, while males engaged in more exploring and sitting alone. In addition BPA increased display of nose-to-nose contacts, play solicitations and approaches in both sexes. Interactions between sex and diet were found for self grooming, social interactions while sitting side-by-side and following the other mouse. In all these cases interactions were produced by differences between control and BPA females. We examined brains from embryos during late gestation to determine if gene expression differences might be correlated with some of the sexually dimorphic or BPA affected behaviors we observed. Because BPA treatments ended at birth we took the brains during embryogenesis to increase the probability of discovering BPA mediated effects. We also selected this embryonic age (E18.5) because it coincides with the onset of sexual differentiation of the brain. Interestingly, mRNA for the glutamate transporter, Slc1a1, was enhanced by exposure to BPA in female brains. Also we noted that BPA changed the expression of two of the three DNA methyltransferase genes, Dnmt1 and Dnmt3a. We propose that BPA affects DNA methylation of Sc1a1 during neural development. Sex differences in juvenile social interactions are affected by BPA and in particular this compound modifies behavior in females

WATTLE SIZE IS CORRELATED WITH MALE TERRITORIAL RANK IN JUVENILE RING-NECKED PHEASANTS

We used morphological measurements and behavioral observations to investigate the relationship between male ornaments and male social rank during the breeding season in a free-ranging population of one-year-old Ring-necked Pheasants (Phasianus colchicus). The sample was of birds of the same age class to avoid the confounding effect of age differences. Tail length, used by females in mate choice, and tarsal spur length, used by males as a weapon in fights, were not correlated with male rank, whereas the size of the wattle was the most important trait. This combined with recent studies showing that wattle size reliably indicates male testosterone levels at the beginning of the breeding season suggest that, among males, wattle size may be used as a signal of aggression level, and body condition. Utilizamos medidas morfológicas y observaciones de comportamiento para investigar la relación entre los ornamentos de los machos y el rango social de éstos durante la época reproductiva en una población silvestre de faisanes Phasianus colchicus de un año de edad. La muestra consistió´ de aves de la misma clase de edad para evitar el efecto de diferencias entre edades. La longitud de la cola (utilizada por las hembras en la selección de pareja) y la longitud de la espuela tarsal (utilizada por los machos como un arma en enfrentamientos) no se correlacionaron con el rango de los machos, mientras que el tamaño de la carúncula fue el caracter más importante. En combinación con estudios recientes que muestran que el tamaño de la carúncula indica confiablemente los niveles de testosterona en los machos al inicio de la época reproductiva, esto sugiere que el tamaño de la carúncula podría ser usado como una señal de niveles de agresión y condición corporal entre los machos

Renin angiotensin system, natriuretic peptides, obesity, metabolic syndrome and hypertension: an integrated view in humans

The obesity pandemic is closely related to hypertension and metabolic syndrome. Visceral adipose tissue plays a key role in the metabolic and cardiovascular complications of being overweight. The pathophysiological link between visceral adiposity and cardiometabolic complications focuses on insulin sensitivity, sympathetic nervous system, renin-angiotensin-aldosterone system (RAAS) and, only recently, on cardiac natriuretic peptide system (CNPS). RAAS and CNPS are endogenous antagonistic systems on sodium balance, cardiovascular system, and metabolism. The circulating RAAS is dysregulated in obese patients, and adipose tissue has a full local renin-angiotensin system that is active at local and systemic level. Adipocyte biology and metabolism are influenced by local renin-angiotensin system, with angiotensin II acting as a 'growth factor' for adipocytes. CNPS induces natriuresis and diuresis, reduces blood pressure, and, moreover, has powerful lipolytic and lipomobilizing activity in humans but not in rodents. In obesity, lower plasmatic natriuretic peptides levels with increasing BMI, waist circumference, and metabolic syndrome have been documented. Thus, reduced CNPS effects coupled with increased RAAS activity have a central role in obesity and its deadly complications. We propose herein an integrated view of the dysregulation of these two antagonistic systems in human obesity complicated with hypertension, metabolic syndrome, and increased cardiovascular risk

Effects of levodopa alone and in combination with dopa-decarboxylase inhibitors on plasma renin activity in patients with Parkinson's disease.

Plasma renin activity (PRA) of patients with Parkinson's disease was measured in recumbency, upright position, and after frusemide administration. The results show that the renin responses to both stimuli are significantly reduced as compared with those obtained in a group of normal subjects, while recumbent PRA levels of Parkinsonism patients are not significantly lower than those found in recumbent normal subjects. Levodopa treatment, alone or in combination with two different dopa-decarboxylase inhibitors, benserazide and carbidopa, does not modify the renin response to posture or to frusemide. Although the reduced activity of the renin-angiotensin system can play some role in the genesis of orthostatic hypotensive episodes encountered in patients with Parkinsonism, the greater incidence of orthostatis hypotension in patients treated with levodopa seems to be unrelated to any effect of this drug on the renin release