Whales, lifespan, phospholipids, and cataracts

Abstract

This study addresses the question: why do rats get cataracts at 2 years, dogs at 8 years, and whales do not develop cataracts for 200 years? Whale lens lipid phase transitions were compared with the phase transitions of other species that were recalculated. The major phospholipids of the whale lens were sphingolipids, mostly dihydrosphingomyelins with an average molar cholesterol/phospholipid ratio of 10. There was a linear correlation between the percentage of lens sphingolipid and lens lipid hydrocarbon chain order until about 60% sphingolipid. The percentage of lens sphingolipid correlated with the lens lipid phase transition temperature. The lifespan of the bowhead whale was the longest of the species measured and the percentage of whale lens sphingolipid fit well in the correlation between the percentage of lens sphingolipid and lifespan for many species. In conclusion, bowhead whale lens membranes have a high sphingolipid content that confers resistance to oxidation, allowing these lenses to stay clear relatively longer than many other species. The strong correlation between sphingolipid and lifespan may form a basis for future studies, which are needed because correlations do not infer cause. One could hope that if human lenses could be made to have a lipid composition similar to whales, like the bowhead, humans would not develop age-related cataracts for over 100 years.

Deiminated proteins and extracellular vesicles - Novel serum biomarkers in whales and orca

“…KEGG pathways relating to cholesterol metabolism were identified in minke whale, fin whale, humpback whale and orca, while KEGG pathways for fat digestion and absorption were identified to be deiminated in minke whale, fin whale and orca. Cholesterol has been studied in whales in relation to lifespan (Borchman et al, 2017) and lipidomics are being developed as a diagnostic tool for metabolic and physiological state in whales, including cholesterol (Tang et al, 2018). Roles for post-translational modifications, including deimination, in cholesterol metabolism remain to be fully understood.…”

The role of lipid metabolism in aging, lifespan regulation, and age‐related disease

“…The bowhead whale, another complex animal with extreme longevity that can live longer than 200 years, has lens membranes that are especially enriched with phospholipids. This unique enrichment is thought to at least partially underlie its uncanny resistance to the age‐related lens disease of cataracts (Borchman, Stimmelmayr, & George, ). Naked mole rats, which enjoy remarkably long lifespans and healthspans for rodents, have a unique membrane phospholipid composition that has been theorized to contribute to their exceptional longevity (Mitchell, Buffenstein, & Hulbert, ).…”

Synchrotron-based FTIR microspectroscopy of protein aggregation and lipids peroxidation changes in human cataractous lens epithelial cells

“…Previously, FTIR microspectroscopy was used to study the whole lens [25][26][27][28][29] . However, FTIR spectroscopy and microscopy were not used to study human LC LECs until now, up to our knowledge.…”