Glycemia Regulation: From Feedback Loops to Organizational Closure

Abstract

Endocrinologists apply the idea of feedback loops to explain how hormones regulate certain bodily functions such as glucose metabolism. In particular, feedback loops focus on the maintenance of the plasma concentrations of glucose within a narrow range. Here, we put forward a different, organicist perspective on the endocrine regulation of glycaemia, by relying on the pivotal concept of closure of constraints. From this perspective, biological systems are understood as organized ones, which means that they are constituted of a set of mutually dependent functional structures acting as constraints, whose maintenance depends on their reciprocal interactions. Closure refers specifically to the mutual dependence among functional constraints in an organism. We show that, when compared to feedback loops, organizational closure can generate much richer descriptions of the processes and constraints at play in the metabolism and regulation of glycaemia, by making explicit the different hierarchical orders involved. We expect that the proposed theoretical framework will open the way to the construction of original mathematical models, which would provide a better understanding of endocrine regulation from an organicist perspective.

Grounding cognition: heterarchical control mechanisms in biology

“…Let us consider, for example, the different and competing production mechanisms involved in the metabolism of glucose and glycogen in mammals (glucose intake, glycolysis, glycogenolysis, gluconeogenesis, glucose transport, etc. ), which need to be coordinated by hormones such as insulin and glucagon released by the pancreas [ 30 ]. The problem of avoiding conflict and coordinating production mechanisms with competing requirements is common to all biological systems.…”

Autonomous Systems and the Place of Biology Among Sciences. Perspectives for an Epistemology of Complex Systems

“…Organization can be understood in terms of static spatial relationships such as in this case, but also in terms of dynamic relationships between components and processes that undergo continuous transformations. In fact, if one focuses on processes and on the activities of components that realize living organisms, regularity and constancy might be the exception rather than the rule, or even the sign of a pathology (Bich et al, 2020). Organisms are adaptive systems whose internal dynamics and the fate and behavior of parts depend on the state of the system and its environment (Bich et al, 2016).…”

“…The other strategy is the new mechanistic one, which aims to provide a causal explanation of how the individual parts of the systems, or the parts of one or several subsystems, functionally operate and interact within autonomous systems to realize specific phenomena. This strategy has been recently applied to model and analyze phenomena such as mammary organogenesis (Montevil et al, 2016) and glycaemia regulation (Bich et al, 2020) from an autonomy perspective. Network and mechanistic strategies provide different information on the system.…”

The Causal Closure of Physics in Real World Contexts

“…mutual dependence such that they both depend on and contribute to maintaining each other. Thus biological organisation is an interlevel affair, involving downward causation as well as upwards emergence, thus enabling teleology [ 12 , 99 ]. From the viewpoint of this paper, these authors are identifying specific sets of levels where effective interlevel causal closure occurs: the topmost level links to the bottom-most level to close the dynamic loop that leads to biological emergence.…”