Dataset Information

Loss of α-actinin-3 during human evolution provides superior cold resilience and muscle heat generation

ABSTRACT: The fast skeletal muscle protein α-actinin-3 is absent in 1.5 billion people worldwide due to homozygosity for a nonsense polymorphism in the ACTN3 gene (R577X). The prevalence of the 577X allele increased as modern humans moved to colder climates, suggesting a link between α-actinin-3 deficiency and improved cold tolerance. Here, we show that humans lacking α-actinin-3 (XX) are superior in maintaining core body temperature during cold-water immersion due to changes in skeletal muscle thermogenesis. Muscles of XX individuals displayed a shift towards more slow-twitch isoforms of myosin heavy chain (MyHC) and sarcoplasmic reticulum (SR) proteins, accompanied by altered neuronal muscle activation resulting in increased tone rather than overt shivering. Experiments on Actn3 knockout mice showed no alterations in brown adipose tissue (BAT) properties that could explain the improved cold tolerance in XX individuals. Thus, this study provides a clear mechanism for the positive selection of the ACTN3 X-allele in cold climates and supports a key thermogenic role of skeletal muscle during cold exposure in humans.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Skeletal Muscle Cell Line

SUBMITTER: JIMMY RODRIGUEZ

LAB HEAD: Hakan Westerblad

PROVIDER: PXD022997 | Pride | 2021-03-16

REPOSITORIES: Pride

ACCESS DATA

Publications

Loss of α-actinin-3 during human evolution provides superior cold resilience and muscle heat generation.

Wyckelsma Victoria L VL Venckunas Tomas T Houweling Peter J PJ Schlittler Maja M Lauschke Volker M VM Tiong Chrystal F CF Wood Harrison D HD Ivarsson Niklas N Paulauskas Henrikas H Eimantas Nerijus N Andersson Daniel C DC North Kathryn N KN Brazaitis Marius M Westerblad Håkan H

American journal of human genetics 20210217 3

The protein α-actinin-3 expressed in fast-twitch skeletal muscle fiber is absent in 1.5 billion people worldwide due to homozygosity for a nonsense polymorphism in ACTN3 (R577X). The prevalence of the 577X allele increased as modern humans moved to colder climates, suggesting a link between α-actinin-3 deficiency and improved cold tolerance. Here, we show that humans lacking α-actinin-3 (XX) are superior in maintaining core body temperature during cold-water immersion due to changes in skeletal ...[more]

PMID: 33600773

Similar Datasets

Project description:Background: The prevalence of type 2 diabetes has increased dramatically in recent decades. Increasing brown adipose tissue (BAT) mass and activity has recently emerged as an interesting approach to not only increase energy expenditure, but also improve glucose homeostasis. BAT can be recruited by prolonged cold exposure in lean, healthy humans. Here, we tested whether cold acclimation could have therapeutic value for patients with type 2 diabetes by improving insulin sensitivity. Methods: Eight type 2 diabetic patients (age 59.3±5.8 years, BMI 29.8±3.2 kg/m2) followed a cold acclimation protocol, consisting of intermittent cold exposure (6 hours/day, 14-14.5 °C) for 12 consecutive days. Before and after cold acclimation, cold-induced BAT activity was assessed by [18F]FDG-PET/CT scanning, insulin sensitivity at thermoneutrality by a hyperinsulinemic-euglycemic clamp, and muscle and WAT biopsies were taken. Results: Cold-induced BAT activity was low, but increased in all patients upon cold acclimation (SUV from 0.40±0.29 to 0.63±0.78, p<0.05). Interestingly, insulin sensitivity showed a very pronounced 40% increase upon cold acclimation (glucose rate of disappearance from 14.9±4.1 to 20.5±6.9 μmol kg-1 min-1, p<0.05). A 40% increase in insulin sensitivity cannot be explained by BAT glucose uptake, in fact basal skeletal muscle GLUT4 content and translocation was markedly increased after cold acclimation, without effects on insulin signaling or AMPk activation. Conclusions: Regular mild cold exposure has marked effects on insulin sensitivity, which are accompanied by small increases in BAT activity and more pronounced effects on skeletal muscle. These data suggest a novel therapeutic option for the treatment of type 2 diabetes. Microarray analysis was performed on abdominal subcutaneous white adipose tissue samples from human type 2 diabetic patients before, and after 10 days of cold acclimation. A total of 14 samples, from 7 subjects, were used for the microarray analysis.

Dataset Information

Loss of α-actinin-3 during human evolution provides superior cold resilience and muscle heat generation

Publications

Loss of α-actinin-3 during human evolution provides superior cold resilience and muscle heat generation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure