Abstract
The use of minerals complexed with organic molecules has been used to enhance their bioavailability and intestinal absorption. The increased nutrient intake provided by finishing diets promotes muscle growth and weight gain; however, it also intensifies the oxidative challenge to which cells are exposed. We aimed to evaluate the proteomic alterations in the Longissimus thoracis muscle of feedlot cattle supplemented with carbo-amino-phospho-chelated minerals compared with inorganic minerals. Sixteen crossbred Nellore × Angus bulls (iBW: 472 ± 4.9 kg, 18 mo old) were randomly assigned to two treatments: (1) INORG - supplementation with sulfate-based mineral sources; (2) TM - supplementation with minerals (Cr, Zn, Mn, Se, S, Cu, and Co; Tortuga(®) Minerals, dsm-firmenich) in the form of carbo-amino-phospho-chelates. The bulls were fed a high-concentrate diet for 89 days. At the end of the finishing period, animals were slaughtered, and Longissimus thoracis muscle samples were collected and stored at -80ºC. Proteomic analysis was performed using a Label-Free approach on the high-resolution ACQUITY IClass Xevo -G2Xs mass spectrometer system (Waters, Manchester, UK). Data were processed using the Progenesis QI for Proteomics software. A total of 1,165 proteins were identified, of which 134 showed differential abundance (DA, p< 0.05). The TM treatment increased the abundance of 61 proteins and decreased the abundance of 73. Functional analysis of the DA protein list using WebGestalt identified that TM increased the abundance of proteins that utilize Zn(2+) as a cofactor, such as CA2 and CA3 (p=0.001), which are responsible for CO2 removal from the cellular environment. Additionally, an increase was observed in ALDOC and pyruvate carboxylase (p=0.019), involved in both glycolysis and amino acid biosynthesis, utilizing Mg(2+) and Cr indirectly. NADK2 and GPHN proteins (p=0.069), involved in cofactor biosynthesis, also demonstrated increased abundance. Proteins CALR and HSPA2, associated with inflammatory processes, were also upregulated (p=0.024). Supplementation with INORG increased the abundance of proteins related to pyruvate and carbon metabolism (MDH2 and ME2, p=0.037), as well as proteins involved in identifying energy status (PRKAB2) and enhancing fatty acid uptake (FATP1; p=0.036). However, a higher abundance of proteins associated with cellular stress (HSPD1, p=0.011), regulation of inflammatory response (DUSP7, FGF8, and MK2; p=0.048), cellular senescence (MK2 and SQSTM1; p=0.072), and mitophagy (EIF2AK3 and SQSTM1; p=0.036), was also observed phenomena interconnected and linked to oxidative stress. Supplementation with carbo-amino-phospho-chelated minerals enhances the abundance of proteins related to cofactor renewal and glycolytic energy metabolism, improves the cellular response to oxidative stress, and mitigates mechanisms associated with natural killer cell activation in the muscle tissue of feedlot cattle fed high-concentrate diets. These findings highlight the potential of carbo-amino-phospho-chelated mineral supplementation in optimizing muscle metabolism and oxidative stress, which are crucial factors for promoting performance, health and meat quality in feedlot cattle.