Publications by authors named "Marjorie Albrecht"

Humans living at high-altitude (HA) have adapted to this environment by increasing pulmonary vascular and alveolar growth. RNA sequencing data from a novel murine model that mimics this phenotypical response to HA suggested estrogen signaling via estrogen receptor alpha (ERα) may be involved in this adaptation. We hypothesized ERα was a key mediator in the cardiopulmonary adaptation to chronic hypoxia and sought to delineate the mechanistic role ERα contributes to this process by exposing novel loss-of-function ERα mutant (ERαMut) rats to simulated HA.

View Article and Find Full Text PDF

Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ER-α), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-α and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling.

View Article and Find Full Text PDF
Article Synopsis
  • Cigarette smoke can hurt lungs by reducing important cells in the bone marrow called hematopoietic progenitor cells (HPCs).
  • Researchers tested a medicine called AMD3100 to see if it could help protect the lungs by increasing the number and function of HPCs when exposed to cigarette smoke.
  • AMD3100 helped improve lung health in mice, making their lungs less damaged from cigarette smoke, which could lead to new treatments for emphysema in the future.
View Article and Find Full Text PDF

17β-Estradiol (E2) attenuates hypoxia-induced pulmonary hypertension (HPH) through estrogen receptor (ER)-dependent effects, including inhibition of hypoxia-induced endothelial cell proliferation; however, the mechanisms responsible for this remain unknown. We hypothesized that the protective effects of E2 in HPH are mediated through hypoxia-inducible factor 1α (HIF-1α)-dependent increases in ERβ expression. Sprague-Dawley rats and ERα or ERβ knockout mice were exposed to hypobaric hypoxia for 2-3 weeks.

View Article and Find Full Text PDF
Article Synopsis
  • E2 (17β-estradiol) impacts lung vascular remodeling in hypoxia-induced pulmonary hypertension by acting through estrogen receptors, but its target genes in this context are unknown.
  • Microarray analysis of HPH rats treated with E2 identified significant changes in gene expression, with certain genes being upregulated or downregulated, suggesting the regulation of an ER-dependent gene set in response to E2.
  • The study identified gremlin 1 as a novel target of the E2-ER axis, indicating that E2 can regulate genes involved in inflammatory and proliferative processes, which could lead to potential therapeutic applications.
View Article and Find Full Text PDF

17β-Estradiol (E2) exerts protective effects on right ventricular (RV) function in pulmonary arterial hypertension (PAH). Since acute exercise-induced increases in afterload may lead to RV dysfunction in PAH, we sought to determine whether E2 allows for superior RV adaptation after an acute exercise challenge. We studied echocardiographic, hemodynamic, structural, and biochemical markers of RV function in male and female rats with sugen/hypoxia (SuHx)-induced pulmonary hypertension, as well as in ovariectomized (OVX) SuHx females, with or without concomitant E2 repletion (75 μg·kg(-1)·day(-1)) immediately after 45 min of treadmill running at 75% of individually determined maximal aerobic capacity (75% aerobic capacity reserve).

View Article and Find Full Text PDF

Estrogens are disease modifiers in PAH. Even though female patients exhibit better right ventricular (RV) function than men, estrogen effects on RV function (a major determinant of survival in PAH) are incompletely characterized. We sought to determine whether sex differences exist in RV function in the SuHx model of PAH, whether hormone depletion in females worsens RV function, and whether E2 repletion improves RV adaptation.

View Article and Find Full Text PDF

The development of pulmonary hypertension (PH) requires multiple pulmonary vascular insults, yet the role of early oxygen therapy as an initial pulmonary vascular insult remains poorly defined. Here, we employ a two-hit model of PH, utilizing postnatal hyperoxia followed by adult hypoxia exposure, to evaluate the role of early hyperoxic lung injury in the development of later PH. Sprague-Dawley pups were exposed to 90% oxygen during postnatal days 0-4 or 0-10 or to room air.

View Article and Find Full Text PDF

Endothelin-1 is a potent mediator of sepsis-induced pulmonary hypertension (PH). The pulmonary vascular effects of selective blockade of endothelin receptor subtype A (ETAR) during endotoxemia remain unknown. We hypothesized that selective ETAR antagonism attenuates endotoxin-induced PH and improves pulmonary artery (PA) vasoreactivity.

View Article and Find Full Text PDF

Fibroblast growth factor 23 (FGF23) gain of function mutations can lead to autosomal dominant hypophosphatemic rickets (ADHR) disease onset at birth, or delayed onset following puberty or pregnancy. We previously demonstrated that the combination of iron deficiency and a knock-in R176Q FGF23 mutation in mature mice induced FGF23 expression and hypophosphatemia that paralleled the late-onset ADHR phenotype. Because anemia in pregnancy and in premature infants is common, the goal of this study was to test whether iron deficiency alters phosphate handling in neonatal life.

View Article and Find Full Text PDF

Rationale: 17β-Estradiol (E2) attenuates hypoxic pulmonary vasoconstriction and hypoxic pulmonary hypertension (HPH) through an unknown mechanism that may involve estrogen receptors (ER) or E2 conversion to catecholestradiols and methoxyestradiols with previously unrecognized effects on cardiopulmonary vascular remodeling.

Objectives: To determine the mechanism by which E2 exerts protective effects in HPH.

Methods: Male rats were exposed to hypobaric hypoxia while treated with E2 (75 μg/kg/d) or vehicle.

View Article and Find Full Text PDF

Smoking causes lung cancer and chronic obstructive pulmonary disease (COPD) that impose severe health problem to humans. Both diseases are related to each other and can be induced by chronic inflammation in the lung. To identify the molecular mechanism for lung cancer formation, a CCSP-rtTA/(teto)(7)Stat3C bitransgenic model was generated recently.

View Article and Find Full Text PDF

Objective: To determine if intraarticular (IA) injection of hyaluronan (HA) into the canine knee after anterior cruciate ligament transection (ACLT) alters the progression of osteoarthritis (OA) and the perception of pain in this model.

Methods: OA was induced in 30 adult dogs of mixed breed by ACLT. The dogs were divided into 3 groups and given 5 weekly IA injections into the unstable knee during Weeks 1-5 and 13-17.

View Article and Find Full Text PDF

The ability of misoprostol to reverse the deleterious changes induced in cartilage by sodium salicylate was tested using osteoarthritic canine and chondrocytes. Adult mongrel dogs were subjected to anterior cruciate ligament transection and dosed with either misoprostol, salicylate, or misoprostol plus salicylate. No significant differences were noted among the three groups in either gross and histological changes or general biochemical changes.

View Article and Find Full Text PDF