Energy Metabolism and Allocation in Selfish Immune System and Brain: A Beneficial Role of Insulin Resistance in Aging

There is relatively limited knowledge concerning our understanding of how our immune system and brain take most of the available energy in a selfish manner to compensate for their own needs on priority in high energy demanding situations. The main objective of this review is to understand the energy allocation to immune system and brain in infections and/or fight or flight situations. The immune system and brain behave in a selfish manner as they allocate themselves majority of the total available energy. Insulin resistance (IR) is used as a tool for energy allocation by these systems. The immune system is activated as a response to stress and infection. Similarly, the brain gets activated as a response to any external environmental impulse, anxiety, and/or mental factor. These situations need to be dealt in a way to minimize their adverse health effects. The immune system and the brain in such situations need enormous energy for activation which is derived from the energy quota otherwise allocated to other organs. This maximum flux of energy towards these systems is achieved by making rest of the organs less responsive to insulin, a condition known as IR. As immune system and brain do not depend upon insulin for uptake of glucose, these systems are benefited from IR. IR is indicated as a beneficial role ensuring maximum energy allocation to these systems for improving health and well-being.