A Look at Lipid Replacement Therapy
There has been more interest of late in how to engineer ways to sneak useful proteins past the digestive system so that they can be added to the diet but still find their way into cells. Researchers here combine this with the idea that you can dilute the proportion of damaged lipids present in cell membranes by providing a patient with a supply of undamaged lipids, larger than the body would otherwise generate on its own. I am not familiar enough with this line of work to be able to comment on how useful it is in practice, or whether the balance of evidence suggests that the observed results in trials actually occur due to the replacement of damaged lipids, as the authors state below. It is nonetheless quite interesting in the context of the membrane pacemaker hypothesis:
Lipid Replacement Therapy, the use of functional oral supplements containing cell membrane phospholipids and antioxidants, has been used to replace damaged, usually oxidized, membrane glycerophospholipids that accumulate during aging and in various clinical conditions in order to restore cellular function.This approach differs from other dietary and intravenous phospholipid interventions in the composition of phospholipids and their defense against oxidation during storage, ingestion, digestion and uptake as well as the use of protective molecules that noncovalently complex with phospholipid micelles and prevent their enzymatic and bile disruption.
Once the phospholipids have been taken in by transport processes, they are protected by several natural mechanisms involving lipid receptors, transport and carrier molecules and circulating cells and lipoproteins until their delivery to tissues and cells where they can again be transferred to intracellular membranes by specific and nonspecific transport systems. Once delivered to membrane sites, they naturally replace and stimulate removal of damaged membrane lipids.
Various chronic clinical conditions are characterized by membrane damage, mainly oxidative but also enzymatic, resulting in loss of cellular function. This is readily apparent in mitochondrial inner membranes where oxidative damage to phospholipids like cardiolipin and other molecules results in loss of trans-membrane potential, electron transport function and generation of high-energy molecules. Recent clinical trials have shown the benefits of Lipid Replacement Therapy in restoring mitochondrial function and reducing fatigue in aged subjects and patients with a variety of clinical diagnoses that are characterized by loss of mitochondrial function and include fatigue as a major symptom.