CM-MM and ACE genotypes and physiological prediction of the creatine kinase response to exercise

Abstract

Exertional rhabdomyolysis (ERB) is a syndrome of severe skeletal muscle breakdown. Blood levels of creatine kinase (CK) are widely used as a marker to reflect muscle breakdown. Some individuals exhibit extreme increases in blood CK after exercise and have been characterized as high responders (HR), but no clinical definition of HR exists and reasons for the HR phenomenon are not understood. This study investigated possible associations between the magnitude of the CK response to exercise and polymorphisms of two genes: muscle-specific creatine kinase (CK-MM) NcoI and angiotensin-converting enzyme (ACE) I/D. An exercise test for defining HR was also investigated. Participants (n = 88) underwent an exercise test that included stepping up and down two stairs for 5 min followed by 15 squats while wearing a backpack weighted at 30% of their body weight. CK levels were measured before, immediately after, and 48 and 72 h after the test. Nine participants (10.2%) were defined as HR. Participants with the CK-MM NcoI AA genotype had a sixfold higher risk of being HR compared with GG and AG genotypes (P = 0.031). No significant differences were found for the ACE I/D polymorphism. Percent body fat was an independent predictor of being a HR. We conclude that the CK-MM AA genotype and percent body fat may be part of the constellation of mechanisms that explain susceptibility to ERB. A physiological test that may assist in predicting ERB is also presented.

Genetic polymorphisms influence runners’ responses to the dietary ingestion of antioxidant supplementation based on pequi oil (Caryocar brasiliense Camb.): a before-after study

“…It has been reported that CK-MM polymorphism influence physiological responses to exercise [42,56]. Although our results did not demonstrate this association with the analyzed parameters, at least for the CK-MM TaqI polymorphism, the correlation found between this polymorphism and distance covered could compromise any possible association.…”

Comparison of Muscle-Specific Creatine Kinase (CK-MM) Gene Polymorphism (rs8111989) Among Professional, Amateur Athletes and Non-athlete Karatekas

“…The CKMM AA genotype was associated with high values of VO 2 max and this result showed that Iranian athletes and non-athletes had more endurance potential (4). As the G allele is the rare allele for the CKM-NcoI polymorphism, researchers have speculated that this allele is associated with a protective mechanism against muscle breakdown (15).…”

“…It is believed that the A/G polymorphism is also associated with different CK-MM activities in myocytes (13). The frequency of the minor G allele in this type of polymorphism varies in the range from 15% in the Chinese population to 29% -35% in Caucasians and 32% in white Americans (14)(15)(16). Recently interdependence between the CK-MM A/G polymorphism and individual differences in the expression of the physical qualities of a person has been shown in several studies (17,18).…”

Comparison of different ways of expressing creatine kinase concentration of soccer players during a competitive season

“…However, the CK response to exercise shows great individual variability 9,26,27 because it is influenced by personal factors, such as gender, race, muscle mass, training status 23 , and genetic predisposition 28 . Therefore, the same training stimulus can cause different individuals to be classified as having a high or low response to increased [CK serum ].…”