RESUMEN
Metabolic syndrome (MetS), which includes obesity, diabetes, hypertension, hyperlipidemia, and fatty-liver disease, affects more than two-thirds of the U.S. population. Surgical weight loss has been popularized in the last several decades as a means to produce significant weight loss and improvements in the comorbidities of MetS. Women are by far the most common recipients of these surgeries (more than 85%). Women of childbearing age are very likely to pursue surgical weight loss to improve their reproductive function and fertility for childbearing purposes. Significant research using pre-clinical models from our laboratory and clinical data from around the world suggest that surgical weight loss before pregnancy may have negative consequences for offspring. The present study investigates the metabolic endpoints in female-rodent offspring born to dams who had previously received vertical sleeve gastrectomy (VSG) before pregnancy. Comparisons were made to offspring from lean and obese dams. In the adult offspring of either maternal VSG or sham surgery, no differences in body weight, body fat, or lean body mass between groups were identified. The blood pressure measured in a subset of female offspring showed no differences between the VSG and the sham groups. Estrus cyclicity measured by lavage on serial days showed altered cycles in the VSG offspring compared to the controls. For animals that had previously only been exposed to chow, rats were fasted overnight and then given a 1 g meal of either chow or a novel high-fat diet (HFD). The animals were euthanized and paraformaldehyde (PFA)-perfused to perform brain immunohistochemistry for c-Fos, an immediate-early gene activated by novel stimuli. In the VSG rats exposed to either the chow or the HFD meal, the c-Fos-activated cells were significantly blunted in the nucleus of the solitary tract (p < 0.05), the paraventricular nucleus of the hypothalamus (PVN) (p < 0.05), and the dorsal medial nucleus of the hypothalamus (DMH) (p < 0.05) in comparison to the sham controls. These data suggest that the hypothalamic wiring within the brain that controls the response to nutrients and reproductive function was significantly altered in the VSG offspring compared to the offspring of the dams that did not receive weight-loss surgery.
RESUMEN
Maternal stressors during the prenatal and perinatal periods are associated with increased susceptibility for and severity of chronic disease phenotypes in adult offspring. In this study, we used a rat model of maternal high-fat diet (HFD) exposure during pregnancy and lactation to investigate the impact on skeletal homeostasis in offspring. In the distal femur, young male and female offspring (up to 3 weeks of age) from dams fed a HFD exhibited marked increases in trabecular bone volume relative to offspring from dams fed a chow diet, but this was followed by sustained bone loss. By 15 weeks of age, male offspring of HFD fed dams exhibited a 33% reduction in trabecular bone volume fraction that histomorphometric analyses revealed was due to a nearly threefold increase in the abundance of bone-resorbing osteoclasts, while there were no differences between female control and HFD offspring by 15 weeks of age. The osteoblastic differentiation of male offspring-derived bone marrow stromal cells was not affected by maternal diet. However, osteoclastic precursors isolated from the male offspring of HFD fed dams exhibited enhanced differentiation in vitro, forming larger osteoclasts with higher expression of the fusion marker DC-STAMP. This effect appears to be mediated by a cell autonomous increase in the sensitivity of precursors to RANKL. Taken together, these results suggest that maternal stressors like HFD exposure have persistent consequences for the skeletal health of offspring that may ultimately lead to a predisposition for osteopenia/osteoporosis.
