Effects of Developmental Hypoxia on the Vertebrate Cardiovascular System

Abstract

Developmental hypoxia has profound and persistent effects on the vertebrate cardiovascular system, but the nature, magnitude and long-term outcome of the hypoxic consequences are species-specific. Here we aim to identify common and novel cardiovascular responses among vertebrates that encounter developmental hypoxia, and we discuss the possible medical and ecological implications.

Embryonic and juvenile snakes (Natrix maura, Linnaeus 1758) compensate for high elevation hypoxia via shifts in cardiovascular physiology and metabolism

“…Our results corroborate this expectation, though we did not directly measure compensatory biochemical changes in blood, for example enhanced O 2 affinity to hemoglobin or hemoglobin concentration (Gangloff et al, 2019; Lu et al, 2015; Storz et al, 2010; Storz, 2016). In accordance with expectations based on previous work in nonsnake reptiles (Cordero et al, 2017a; Crossley et al, 2017; Du et al, 2010; Galli et al, 2023; Kam, 1993), physiological adjustments resulted in no effect of hypoxia on incubation duration, nor was phenotype at hatching or phenotype after being maintained 4 weeks at their elevation of incubation affected (Table 2). The consistency of embryo and hatchling phenotype across treatment groups suggests that physiological mechanisms may compensate for suboptimal environmental conditions (here, hypoxia).…”

“…Future work should be directed to quantifying the potential of maternal behavioral choices in affecting offspring development and survival, as has been identified in a variety of reptilian taxa (Bodensteiner et al, 2023; Burger & Zappalorti, 1986; Escalona et al, 2009; Peet‐Paré & Blouin‐Demers, 2012; Pike et al, 2010; Refsnider et al, 2010). Even though early‐life traits are maintained, population establishment will depend on the long‐term costs associated with life in reduced oxygen availability and the consequences of reduced performance (Bodensteiner, Gangloff et al, 2021; Galli et al, 2023; Gangloff et al, 2019). Furthermore, it would be fruitful to quantify expression of important genes relevant to differentiation and growth in response to hypoxia, as has recently been done for lizard embryos exposed to thermal stress (Sanger et al, 2021).…”

“…In oviparous reptiles, most embryonic development occurs after the eggs are laid in unattended subterranean nests (Ackerman & Lott, 2004; Packard & Packard, 1988). The egg environment limits embryonic motility and therefore the range of behavioral responses available to embryos (Cordero et al, 2018; Telemeco et al, 2016, but see Du & Shine, 2022), thereby prioritizing physiological responses to adverse conditions (Galli et al, 2023; Hall & Sun, 2021). In subterranean nests, additional challenges are low oxygen levels and fluctuations in gas concentrations (Ackerman & Lott, 2004; Deeming & Thompson, 1991; Packard & Packard, 1988; Seymour & Ackerman, 1980; Stahlschmidt & DeNardo, 2009).…”

“…Exposure to hypoxia during development may induce plastic changes in cardiovascular, muscular, or mitochondrial function to increase performance capacity under these oxygen-limited conditions (Eme et al, 2013;Galli et al, 2016Galli et al, , 2023Sun et al, 2015). Such stress-induced physiological responses might promote offspring survival in response to consistently low O 2 partial pressure.…”

Epigenetic regulation by hypoxia, N‐acetylcysteine and hydrogen sulphide of the fetal vasculature in growth restricted offspring: A study in humans and chicken embryos

“…One of the most common adverse intrauterine conditions known to programme cardiovascular disease in offspring is gestational hypoxia leading to fetal growth restriction (FGR) (Ducsay et al., 2018; Galli et al., 2023; Giussani, 2021; Giussani & Davidge, 2013). Studies in animal models have established that underlying pathways stimulated by this condition include the genesis of oxidative stress in the developing fetal cardiovascular system (Giussani, 2021; Giussani & Davidge, 2013; Giussani et al., 2012; Herrera et al., 2014; Krause, Costello et al., 2013; Penaloza et al., 2020).…”