Unknown

Dataset Information

0

Insulin resistance in cavefish as an adaptation to a nutrient-limited environment.


ABSTRACT: Periodic food shortages are a major challenge faced by organisms in natural habitats. Cave-dwelling animals must withstand long periods of nutrient deprivation, as-in the absence of photosynthesis-caves depend on external energy sources such as seasonal floods. Here we show that cave-adapted populations of the Mexican tetra, Astyanax mexicanus, have dysregulated blood glucose homeostasis and are insulin-resistant compared to river-adapted populations. We found that multiple cave populations carry a mutation in the insulin receptor that leads to decreased insulin binding in vitro and contributes to hyperglycaemia. Hybrid fish from surface-cave crosses carrying this mutation weigh more than non-carriers, and zebrafish genetically engineered to carry the mutation have increased body weight and insulin resistance. Higher body weight may be advantageous in caves as a strategy to cope with an infrequent food supply. In humans, the identical mutation in the insulin receptor leads to a severe form of insulin resistance and reduced lifespan. However, cavefish have a similar lifespan to surface fish and do not accumulate the advanced glycation end-products in the blood that are typically associated with the progression of diabetes-associated pathologies. Our findings suggest that diminished insulin signalling is beneficial in a nutrient-limited environment and that cavefish may have acquired compensatory mechanisms that enable them to circumvent the typical negative effects associated with failure to regulate blood glucose levels.

SUBMITTER: Riddle MR 

PROVIDER: S-EPMC5989729 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

altmetric image

Publications


Periodic food shortages are a major challenge faced by organisms in natural habitats. Cave-dwelling animals must withstand long periods of nutrient deprivation, as-in the absence of photosynthesis-caves depend on external energy sources such as seasonal floods. Here we show that cave-adapted populations of the Mexican tetra, Astyanax mexicanus, have dysregulated blood glucose homeostasis and are insulin-resistant compared to river-adapted populations. We found that multiple cave populations carr  ...[more]

Similar Datasets

| S-EPMC4534248 | biostudies-literature
| S-EPMC2915681 | biostudies-literature
2022-12-30 | GSE192969 | GEO
| S-EPMC6650306 | biostudies-literature
2019-04-09 | GSE129089 | GEO
| S-EPMC8835132 | biostudies-literature
| S-EPMC6358685 | biostudies-literature
2019-08-22 | GSE126767 | GEO
| S-EPMC9178706 | biostudies-literature
| S-EPMC7274492 | biostudies-literature