Dose-related cardiac outcomes in response to postnatal dexamethasone treatment in premature lambs.

BACKGROUND: Postnatal corticosteroids are used in the critical care of preterm infants for the prevention and treatment of bronchopulmonary dysplasia. We aimed to investigate the effects of early postnatal dexamethasone therapy and dose on cardiac maturation and morphology in preterm lambs. METHODS: Lambs were delivered prematurely at ~128 days of gestational age and managed postnatally according to best clinical practice. Preterm lambs were administered dexamethasone daily at either a low-dose (n = 9) or a high-dose (n = 7), or were naïve to steroid treatment and administered saline (n = 9), over a 7-day time-course. Hearts were studied at postnatal Day 7 for gene expression and assessment of myocardial structure. RESULTS: High-dose dexamethasone treatment in the early postnatal period led to marked differences in cardiac gene expression, altered cardiomyocyte maturation and reduced cardiomyocyte endowment in the right ventricle, as well as increased inflammatory infiltrates into the left ventricle. Low-dose exposure had minimal effects on the preterm heart. CONCLUSION: Neonatal dexamethasone treatment led to adverse effects in the preterm heart in a dose-dependent manner within the first week of life. The observed cardiac changes associated with high-dose postnatal dexamethasone treatment may influence postnatal growth and remodeling of the preterm heart and subsequent long-term cardiac function.

Q-122 as a novel, non-hormonal, oral treatment for vasomotor symptoms in women taking tamoxifen or an aromatase inhibitor after breast cancer: a phase 2, randomised, double-blind, placebo-controlled trial.

BACKGROUND: Vasomotor symptoms (hot flushes and night sweats) are experienced by more than two-thirds of women with breast cancer taking oral adjuvant endocrine therapy. Safe and effective treatments are lacking. Q-122 is a novel, non-hormonal compound that has shown promise for reducing vasomotor symptoms by modulation of oestrogen-responsive neurons in the hypothalamus. We aimed to assess the efficacy and safety of Q-122 in women with breast cancer taking oral adjuvant endocrine therapy and experiencing vasomotor symptoms. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled, proof-of-concept, phase 2 trial at 18 sites in Australia, New Zealand, and the USA. Eligible participants were women, aged 18-70 years, taking a stable dose of tamoxifen or an aromatase inhibitor following breast cancer and experiencing at least 50 self-reported moderate to severe vasomotor symptoms per week. Participants were randomly assigned (1:1) using an interactive web response system to oral Q-122 100 mg or identical placebo, twice daily for 28 days. Randomisation was stratified by BMI (≤30 kg/m2 or >30 kg/m2) and use of any of a selective serotonin reuptake inhibitor, selective norepinephrine reuptake inhibitor, gabapentin, or pregabalin. Q-122 and placebo capsules were identical in appearance and containers identically labelled. During the double-blind treatment and analysis phases, the participants, investigators, clinical research organisation staff, and sponsor were masked to treatment allocation. The primary outcome was the difference in the mean percentage change from baseline in the Vasomotor Symptom Severity Score of moderate and severe hot flushes and night sweats (msVMS-SS) between Q-122 and placebo after 28 days of treatment. Primary analysis was by modified intention-to-treat and safety was assessed in all participants receiving at least one dose of study drug. This study is registered at ClinicalTrials.gov, NCT03518138. FINDINGS: Between Oct 24, 2018, and Sept 9, 2020, 243 patients were screened, 131 of whom were randomly assigned and received treatment (Q-122 n=65 and placebo n=66). Q-122 resulted in a significantly greater mean percentage change in msVMS-SS from baseline over 28 days of treatment compared with placebo (least squares mean: Q-122 -39% [95% CI -46 to -31] vs placebo -26% [-33 to -18]; p=0·018). Treatment-emergent adverse events were generally mild to moderate and similar between the two groups (treatment-related treatment-emergent adverse events in 11 [17%] of 65 patients in the Q-122 group vs nine [14%] of 66 in the placebo group); zero patients in the Q-122 group and two (3%) patients in the placebo group had serious adverse events. INTERPRETATION: Q-122 is an effective and well tolerated non-hormonal oral treatment for vasomotor symptoms in women taking oral adjuvant endocrine therapy after breast cancer. Our results support the conduct of larger and longer studies of Q-122, with potential use extending to postmenopausal women who require an alternative to menopausal hormone therapy. FUNDING: QUE Oncology.

Intrauterine inflammation exacerbates maladaptive remodeling of the immature myocardium after preterm birth in lambs.

BACKGROUND: Antenatal conditions that are linked with preterm birth, such as intrauterine inflammation, can influence fetal cardiac development thereby rendering the heart more vulnerable to the effects of prematurity. We aimed to investigate the effect of intrauterine inflammation, consequent to lipopolysaccharide exposure, on postnatal cardiac growth and maturation in preterm lambs. METHODS: Preterm lambs (~129 days gestational age) exposed antenatally to lipopolysaccharide or saline were managed according to contemporary neonatal care and studied at postnatal day 7. Age-matched fetal controls were studied at ~136 days gestational age. Cardiac tissue was sampled for molecular analyses and assessment of cardiac structure and cardiomyocyte maturation. RESULTS: Lambs delivered preterm showed distinct ventricular differences in cardiomyocyte growth and maturation trajectories as well as remodeling of the left ventricular myocardium compared to fetal controls. Antenatal exposure to lipopolysaccharide resulted in further collagen deposition in the left ventricle and a greater presence of immune cells in the preterm heart. CONCLUSIONS: Adverse impacts of preterm birth on cardiac structure and cardiomyocyte growth kinetics within the first week of postnatal life are exacerbated by intrauterine inflammation. The maladaptive remodeling of the cardiac structure and perturbed cardiomyocyte growth likely contribute to the increased vulnerability to cardiac dysfunction following preterm birth. IMPACT: Preterm birth induces maladaptive cardiac remodeling and adversely impacts cardiomyocyte growth kinetics within the first week of life in sheep. These effects of prematurity on the heart are exacerbated when preterm birth is preceded by exposure to intrauterine inflammation, a common antecedent of preterm birth. Inflammatory injury to the fetal heart coupled with preterm birth consequently alters neonatal cardiac growth and maturation and thus, may potentially influence long-term cardiac function and health.

Effect of Preterm Birth on Cardiac and Cardiomyocyte Growth and the Consequences of Antenatal and Postnatal Glucocorticoid Treatment.

Preterm birth coincides with a key developmental window of cardiac growth and maturation, and thus has the potential to influence long-term cardiac function. Individuals born preterm have structural cardiac remodelling and altered cardiac growth and function by early adulthood. The evidence linking preterm birth and cardiovascular disease in later life is mounting. Advances in the perinatal care of preterm infants, such as glucocorticoid therapy, have improved survival rates, but at what cost? This review highlights the short-term and long-term impact of preterm birth on the structure and function of the heart and focuses on the impact of antenatal and postnatal glucocorticoid treatment on the immature preterm heart.

Maternal dietary intake during pregnancy has longstanding consequences for the health of her offspring.

Over the past 100 years, advances in pharmaceutical and medical technology have reduced the burden of communicable disease, and our appreciation of the mechanisms underlying the development of noncommunicable disease has broadened. During this time, a number of studies, both in humans and animal models, have highlighted the importance of maintaining an optimal diet during pregnancy. In particular, a number of studies support the hypothesis that suboptimal maternal protein and fat intake during pregnancy can have long-term effects on the growing fetus, and increase the likelihood of these offspring developing cardiovascular, renal, or metabolic diseases in adulthood. More recently, it has been shown that dietary intake of a number of micronutrients may offset or reverse the deleterious effects of macronutrient imbalance. Furthermore, maternal fat intake has also been identified as a major contributor to a healthy fetal environment, with a beneficial role for unsaturated fats during development as well as a beneficial impact on cell membrane physiology. Together these studies indicate that attempts to optimise maternal nutrition may prove to be an efficient and cost-effective strategy for preventing the development of cardiovascular, renal, or metabolic diseases.