Expression of calpain system transcripts responds inversely to beef tenderization after vitamin D3 supplementation in Nellore cattle

Abstract

The calpain system is the central player for meat tenderization and the calpastatin activity plays an important role in beef tenderness of Bos taurus indicus cattle. This study investigated whether dietary vitamin D3 induced gene expression of μ-calpain (CAPN1), total calpastatin (CAST T), and their variants (CAST I and II). Animals received none or 2 × 106 IU of vitamin D3 for either 2 or 8 days before slaughter and were submitted to different conditions during feedlot: sun exposure or artificial shade. Steaks from Longissimus lumborum were fabricated, aged for 1, 7, and 21 days post-mortem, and later used for the analyses of shear force and the myofibrillar fragmentation index. Vitamin D3 did not influence mRNA abundance; however, it induced a greater CAST II transcript in animals supplemented 8 days before slaughter. There was a negative association between CAST II abundance and the shear force, which revealed an important modulation of the calpain system expression due to vitamin D supplementation. This result is an important tool for strategies to improve beef tenderness.

Effect of vitamin or mineral supplementation on oxidation and quality traits of fresh and aged beef

“…Therefore, the immobilization of calcium in animals supplemented with vitamin D may have favored greater myofibrillar fragmentation (Lobo-Jr. et al, 2012). Such results corroborate those reported, in which vitamin D-enriched diets beneficially increase postmortem proteolysis and improve myofibrillar fragmentation, thus improving beef tenderness (Duffy et al, 2017;Karges et al, 2001;Lobo-Jr. et al, 2012;Montgomery et al, 2000Montgomery et al, , 2002Montgomery et al, , 2004Rezende et al, 2021) by increasing the concentration of free calcium in the muscle as well as the antioxidant capacity (Lobo-Jr. et al, 2012).…”