Maternal protein restriction differentially alters the expression of AQP1, AQP9 and VEGFr-2 in the epididymis of rat offspring.

BACKGROUND: Maternal protein restriction causes sperm alterations in the offspring, most of which are associated with epididymal functions. Because fluid reabsorption/secretion dynamics in the epididymal environment play important roles in the process of sperm maturation and concentration, we investigated the effects of maternal protein restriction on the expression of aquaporins (AQP1 and AQP9), vascular endothelial growth factor (VEGFa), and its receptor VEGFr-2 in different stages of postnatal epididymal development. METHODS: Pregnant rats were divided into groups that received normoprotein (17% protein) and low-protein diets (6% protein) during gestation and lactation. After weaning, male rats only received the standard diet and were euthanized at the predetermined ages of 21, 44 and 120 days. RESULTS: Maternal protein restriction decreased AQP1 and AQP9 expression in the initial segment and caput epididymis compared to the increased expression of these proteins observed in the corpus and cauda at all ages. Although protein restriction reduced the microvasculature density (MVD) on postnatal day (PND) 21 and 44, the MVD was unaltered on PND 120. CONCLUSIONS: Maternal protein restriction changed the structure or function of the offspring's epididymis, specifically by affecting fluid dynamics and vasculogenesis in important stages of epididymis development.

Maternal protein restriction affects the differentiation of cells in the epididymal epithelium lining of 44-day-old rats.

Maternal protein restriction delays the differentiation of epididymal mesenchymal cells in newborn rats. However, it's unclear if this delay persists until the full differentiation of the epididymal epithelium at 44 days postnatal. Thus, this study aimed to assess the impact of maternal protein reduction on 44-day-old rats' epididymal epithelium differentiation, following up on the observed delay in newborn animals. Pregnant rats were randomly divided into groups receiving normal-protein (NP - 17% protein) or low-protein (LP - 6% protein) diets during gestation and lactation. On postnatal day (PDN) 44, male offspring were euthanized, and the epididymis (NP n=10, LP n=10) was processed according to immunohistochemical techniques for the detection of aquaporin 9 (AQP9), KI-67, TP63, and ATPase. LP rats showed: a decrease in the intensity of the AQP9 reaction, an increase in cellular proliferation in the initial segment and corpus of the epididymis, an increase in basal cells in the caput and corpus epididymis, and an increase in ATPase-positive clear cells in the cauda region. These findings demonstrate that maternal protein restriction impacts cell differentiation in the epididymal epithelium of 44-day-old rats, persisting even with a normal-protein diet after weaning.

Maternal Protein Restriction Alters the Expression of Proteins Related to the Structure and Functioning of the Rat Offspring Epididymis in an Age-Dependent Manner.

Nutrition is an environmental factor able to activate physiological interactions between fetus and mother. Maternal protein restriction is able to alter sperm parameters associated with epididymal functions. Since correct development and functioning of the epididymides are fundamental for mammalian reproductive success, this study investigated the effects of maternal protein restriction on epididymal morphology and morphometry in rat offspring as well as on the expression of Src, Cldn-1, AR, ER, aromatase p450, and 5α-reductase in different stages of postnatal epididymal development. For this purpose, pregnant females were allocated to normal-protein (NP-17% protein) and low-protein (LP-6% protein) groups that received specific diets during gestation and lactation. After weaning, male offspring was provided only normal-protein diet until the ages of 21, 44, and 120 days, when they were euthanized and their epididymides collected. Maternal protein restriction decreased genital organs weight as well as crown-rump length and anogenital distance at all ages. Although the low-protein diet did not change the integrity of the epididymal epithelium, we observed decreases in tubular diameter, epithelial height and luminal diameter of the epididymal duct in 21-day-old LP animals. The maternal low-protein diet changed AR, ERα, ERß, Src 416, and Src 527 expression in offspring epididymides in an age-dependent manner. Finally, maternal protein restriction increased Cldn-1 expression throughout the epididymides at all analyzed ages. Although some of these changes did not remain until adulthood, the insufficient supply of proteins in early life altered the structure and functioning of the epididymis in important periods of postnatal development.

Exercise-Induced Modulation of Angiotensin II Responses in Femoral Veins From 2-Kidney-1-Clip Hypertensive Rats.

The present study investigated the angiotensin II (Ang II) responses in rat femoral veins taken from 2-kidney-1clip (2K1C) hypertensive rats at 4 weeks after clipping, as well as the effects of exercise on these responses. In this manner, femoral veins taken from 2K1C rats kept at rest or exposed to acute exercise or to exercise training were challenged with Ang II or endothelin-1 (ET-1) in organ bath. Simultaneously, the presence of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) were determined in these preparations by western blotting. In these experiments, femoral veins exhibited subdued Ang II responses. However, after nitric oxide (NO) synthesis blockade, the responses were higher in the femoral veins taken from animals kept at rest [0.137(0.049-0.245); n = 10] than those obtained in trained animals kept at rest [0.008(0.001-0.041); n = 10] or studied after a single bout of exercise [0.001(0.001-0.054); n = 11]. In preparations in which, in addition to NO synthesis, both the local production of prostanoids and the action of ET-1 on type A (ETA) or B (ETB) receptors were inhibited, the differences induced by exercise were no longer observed. In addition, neither ET-1 responses nor the presence of COX-1 and COX-2 in these preparations were modified by the employed exercise protocols. In conclusion, NO maintains Ang II responses reduced in femoral veins of 2K1C animals at rest. However, vasodilator prostanoids as well as other relaxing mechanisms, activated by ETB stimulation, are mobilized by exercise to cooperate with NO in order to maintain controlled Ang II responses in femoral veins.

Maternal protein restriction impairs nutrition and ovarian histomorphometry without changing p38MAPK and PI3K-AKT-mTOR signaling in adult rat ovaries.

AIMS: Because an adequate protein supply is detrimental for the maintenance of folliculogenesis and ovulation, we evaluated the impact of maternal low protein diet on nutritional parameters, estrous cycle, ovarian histomorphometry, and on the expression of metabolic and survival signaling molecules in different follicular stages. MAIN METHODS: Twenty Wistar pregnant rats were divided into two groups: the normoprotein (NP) group, composed of animals that received 17% protein, and a low-protein (LP) group, composed of animals that received 6% protein during gestation and lactation period. After weaning, female rats were fed with standard diet until the 120-days-old. KEY FINDINGS: LP animals showed reduced body mass index, total body weight, energy intake, feed efficiency, and visceral fat. The ovarian tissue presented vascular congestion and fat accumulation in the medulla, followed by a significant reduction in the amount of primordial and primary follicles. In addition, the number of atretic follicles was higher in LP than in NP animals. Maternal undernutrition also resulted in increased levels of estradiol (E2) and progesterone (P4) while testosterone (T) was unchanged in the offspring. Although discrete changes in p38MAPK and in PI3K-AKT-mTOR immunostaining were observed in the ovarian follicles and corpus luteum in LP, no differences were found at their protein levels. SIGNIFICANCE: Maternal protein restriction alters estrous cycle and histomorphometry of the offspring's ovary without changing the levels of intracellular regulatory molecules in adulthood. These morphofunctional changes may alter reproductive performance in female offspring, highlighting maternal dietary conditions as an important factor for offspring reproductive health.

Maternal Protein Restriction Modulates Angiogenesis and AQP9 Expression Leading to a Delay in Postnatal Epididymal Development in Rat.

The maternal nutritional status is essential to the health and well-being of the fetus. Maternal protein restriction during the perinatal stage causes sperm alterations in the offspring that are associated with epididymal dysfunctions. Vascular endothelial growth factor (VEGF) and its receptor, VEGFr-2, as well as aquaporins (AQPs) are important regulators of angiogenesis and the epididymal microenvironment and are associated with male fertility. We investigated the effects of maternal protein restriction on epididymal angiogenesis and AQP expression in the early stages of postnatal epididymal development. Pregnant rats were divided into two experimental groups that received either a normoprotein (17% protein) or low-protein diet (6% protein) during gestation and lactation. At postnatal day (PND)7 and PND14, male offspring were euthanized, the epididymides were subjected to morphometric and microvascular density analyses and to VEGF-A, VEGF-r2, AQP1 and AQP9 expression analyses. The maternal low-protein diet decreased AQP9 and VEGFr-2 expression, decreased epididymal microvascularity and altered the morphometric features of the epididymal epithelium; no changes in AQP1 expression were observed at the beginning of postnatal epididymal development. Maternal protein restriction alters microvascularization and affects molecules involved in the epidydimal microenvironment, resulting in morphometric alterations related to a delay in the beginning of epididymis postnatal development.

Protective effect of resveratrol on urogenital sinus and prostate development in rats exposed in utero to TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin).

This study evaluated the protective effects of resveratrol on the prostate development of rats exposed to TCDD. Pregnant rats received TCDD (1 µg/kg) at GD15 and/or RES (20 mg/kg/day) from GD10 to PND21. Newborn and adult males from Control, TCDD, TCDD + RES and RES groups were euthanized and the prostate was excised. On PND1, there was a reduction in the number of prostatic buds, AR-positive mesenchymal cells and proliferation index in epithelial and mesenchymal cells in TCDD group, but restored by RES. AhR immunoreactivity was greater in TCDD group than the other groups. On PND90, there was higher frequency of functional hyperplasia in the distal area of the prostate acini in TCDD group, but restored by RES. AhRR expression was higher in the TCDD while NRF2 was higher in the TCDD + RES compared to the other groups. Resveratrol was able to reduce the adverse effects of TCDD on prostate development and its long-term repercussions.

Alterations in prostate morphogenesis in male rat offspring after maternal exposure to Di-n-butyl-phthalate (DBP).

Prostate morphogenesis is regulated by androgens hormones and modulated by morphogenetic proteins such as Bone Morphogenetic Proteins (BMPs). This study aims to investigate the effects on prostate development in male offspring and differentiation after gestational and lactational maternal exposure to Di-n-butyl-phthalate (DBP), an important environmental contamination. Pregnant Wistar rats received 100 or 500mg/kg of DBP (DBP100 and DBP500), by gavage, from gestation day 15 (GD15) until postnatal day 21 (PND21). The pups were euthanized on PND1 and PND21. Anogenital distance and testosterone levels decreased in animals from exposed mothers (DBP100 and 500) on PND1. A three-dimensional reconstruction model of the prostatic urethra showed reduction in the prostatic buds in the DBP500 group. AR expression and α-actin immunoreactivity decreased, and BMP-4 expression was lower on PND1 for DBP500. These results showed that DBP exposure, especially at a higher dose, delayed prostate morphogenesis by reducing the testosterone/AR axis and BMP-4 expression.