Abstract We aimed to evaluate how high-fat diet consumption can interfere with rat reproductive performance and fetal development. High-fat diet (HFD) was initiated in 30-day-old rats, distributed into two groups (n=7 animals/group): Rats receiving a standard diet and rats receiving HFD. At adulthood, the rats were mated, and on day 21 of pregnancy, the females were anesthetized, decapitated, and submitted to laparotomy to obtain visceral and periovarian adipose tissue. The uterine horns were exposed for analysis of maternal reproductive performance. The fetuses and placentas were weighed and analyzed. Pearson’s correlation test was used, and p<0.05 was considered significant. There was a significant positive correlation (HFD consumption x increased periovarian fat) and a negative correlation with the implantation, live fetus numbers and lower litter weight. Furthermore, the increased relative weight of periuterine fat was related to the lower number of live fetuses and litter weight. Regarding the fetal weight classification, there was a negative correlation between the relative weight of periovarian fat and the percentage of fetuses appropriate for gestational age and large for gestational age. Therefore, our findings show that HFD maternal intake negatively influenced on reproductive performance and fetal growth.

Abstract Pregestational hyperglycemia cause adverse effects on mothers and their offspring. We aimed to evaluate the maternal hyperglycemia influence on pre-embryos from diabetic rats and on their generations (daughters and granddaughters). Diabetes was induced in Sprague-Dawley rats. The mothers and their female pups were submitted to oral glucose tolerance test in adulthood. In day 4 of pregnancy, pre-embryos were collected for morphological analysis. The diabetic mother, daughter and granddaughter rats showed glucose intolerance and their pre-embryos presented developmental delay, degeneration and losses compared to the nondiabetic group. Thus, maternal diabetes transgenerationally affects embryos at early development, which contributes for embryofetal losses.

Abstract This study aimed at evaluating the levels of different maternal exercise intensities on maternal and fetal outcomes. Wistar rats were mated and the pregnant rats were distributed into four experimental groups (n = 13 animals/group): Control (Not exercise group - 0% of the anaerobic threshold- AT), mild (20%), moderate (80%), and heavy-exercise intensity (140% of AT). These AT were matched to the load of 0, 1, 4 and 7% of the body weight of the animal related to swimming-induced physical intensity. In pregnancy, biomarkers related to maternal blood gases, oxidative stress, metabolism, and reproductive performance, and outcomes of their offspring were analyzed. The mild and moderate-swimming caused no change on implantation, live fetus numbers and oxidative stress status. However, the rats submitted to mild-exercise presented respiratory alkalosis and the heavy-exercise group showed respiratory acidosis. In addition, fetuses of the heavy-exercise dams were smaller for gestational age and lower serum adiponectin levels compared to those of other groups. In conclusion, the moderate-exercise intensity caused beneficial effects for maternal environment and the mild and moderate-exercise presented similar fetal repercussions. Nevertheless, the heavy-exercise intensity caused maternal metabolic alterations that damaged the fetal growth. Therefore, these findings confirm that physical intensity should be carefully conducted to avoid maternal complications and, consequently, compromised fetal repercussions.

ABSTRACT Several studies present different methodologies and results about intensity exercise, and many of them are performed in male rats. However, the impact of different type, intensity, frequency and duration of exercise on female rats needs more investigation. From the analysis of blood lactate concentration during lactate minimum test (LacMin) in the swimming exercise, the anaerobic threshold (AT) was identified, which parameter is defined as the transition point between aerobic and anaerobic metabolism. LacMin test is considered a good indicator of aerobic conditioning and has been used in prescription of training in different exercise modalities. However, there is no evidence of LacMin test in female rats. The objective was to determine AT in non-pregnant and pregnant Wistar rats. The LacMin test was performed and AT defined for mild exercise intensity was from a load equivalent to 1% of body weight (bw), moderate exercise as carrying 4% bw and severe intensity as carrying 7% bw. In pregnant rats, the AT was reached at a lower loading from 5.0% to 5.5% bw, while in non-pregnant the load was from 5.5% to 6.0% bw. Thus, this study was effective to identify exercise intensities in pregnant and non-pregnant rats using anaerobic threshold by LacMin test.