Carnosine concentration and expression profiles of carnosine related genes in Mytilus after beta-alanine injection

Carnosine and its analogues are histidine-containing dipeptides(HCDs)playing diverse functions in vertebrates.However,the distribution and the metabolism of carnosine in invertebrates are still unknown.In this study,Mytilus coruscus,a shellfish with important economic value in China,was selected for the investigation of HCD content and the expression profiling of carnosine-related genes in various mussel tissues.Quantification of HCD by amino acids analyzer revealed a low concentration of anserine in muscular tissues in Mytilus,indicating the presence of HCD even in an invertebrate.mRNA expression of five carnosine metabolic-related genes was profiled in various tissues,and the results highlighted the relative higher expression level of these genes in muscular tissues.Considering the fact that beta-alanine supplementation can increase the HCD content in vertebrates,a beta-alanine injection was performed and the changes of HCD concentration and the mRNA expression of carnosine related genes were investigated in five mussel tissues.The results revealed the increase of HCD concentration,as well as the up-regulated expression level of related genes,in tested tissues of beta-alanine injected mussels.Transcriptomic analysis for the whole soft tissue of mussel before and after beta-alanine injection were performed,and 3569 differential expression genes(DEGs)were identified in the beta-alanine injected group when compared to their expression levels in the control.These data indicated the complex eff ects of betaalanine on M.coruscus metabolism,and those DEGs enriched in pathways of cancers,muscle contraction,and tyrosine metabolism highlighted the possible functions of beta-alanine in cell proliferation,sports,and melanogenesis,respectively.

The Effect of 4 Weeks of Strength Training and Beta-Alanine Supplementation on Anaerobic Power and Carnosine Level in Boxer Players

Purpose The objective of this study was to investigate the effect of 4 weeks of strength training with beta-alanine supple-mentation on anaerobic power and carnosine level in boxer players.Methods Eighteen male boxer players participated in this study,randomly divided into two homogeneous groups(strength training+beta-alanine and strength training+placebo groups).The study design was double-blind,parallel,and placebo-controlled.An anaerobic Wingate test was performed by athletes before and after the intervention period(4 weeks).Par-ticipants received 0.3 g/kg of body mass of the supplement(maltodextrin or beta-alanine)per day during the intervention.Participants were also evaluated for anaerobic power,serum level of carnosine,and blood lactate before and after 4 weeks.Results Average power in both groups was significantly increased compared with pre-intervention,but fatigue index was significantly decreased only after beta-alanine supplementation;however,there were no significant differences with either average power or fatigue index between the beta-alanine and placebo groups.There was no significant difference in the interaction between the groups and time,as well as no significant difference between groups for lactic acid.Carnosine level in both groups was significantly increased compared with pre-intervention.When changes in serum carnosine for the two groups were examined,statistical analysis showed a significant difference between the beta-alanine and placebo groups.Conclusion Four weeks of strength training accompanied by beta-alanine supplementation had a likely beneficial effect on boxer players'anaerobic performance and carnosine level.

Effects ofβ-alanine on intestinal development and immune performance of weaned piglets

Beta-alanine is an important amino acid involved in several metabolic reactions in the body.The study aimed to investigate the effect ofβ-alanine supplementation on intestinal development and the immune performance of weaned piglets.Thirty-two 21-day-old healthy weaned piglets(half female and half male;Duroc×Landrace×Yorkshire)with an initial body weight of 8.11±0.21 kg were randomly divided into 4 groups with 8 replicates of 1 pig each.The control group was fed a basal diet and the three experimental treatment groups were fed diets supplemented with 300,600 and 1,200 mg/kgβ-alanine,respectively.The trial lasted 28 days and the diets fed were divided into 2 phases:the late lactation period(day 1 to 14)and the nursery period(day 15 to 28),during which the weaned piglets had free access to food and water.The regulatory effects ofβ-alanine were further investigated in vitro using organoids obtained from the jejunum of piglets.In vivo,the addition ofβ-alanine to the diet had no significant effect on the growth performance of weaned piglets(P>0.05),but significantly reduced serum levels of immunoglobulin G(IgG)(P<0.01),immunoglobulin M(IgM)(P=0.005),and complement 3(C3)(P=0.017).The serum interleukin-6(IL-6)levels(P<0.01)were significantly reduced in the 1,200 mg/kg treatment group.The addition ofβ-alanine increased ileal villus height,with the most significant effect at a concentration of 300 mg/kg(P=0.041).The addition of 600 mg/kgβ-alanine significantly up-regulated the expression of superoxide dismutase(SOD)activity(P=0.020)and the zonula occludens-1(ZO-1)gene(P=0.049)in the jejunum.Diets supplemented with 300 mg/kgβ-alanine significantly increased the number of Ki67 positive cells in the jejunal crypts(P<0.01).In vitro,β-alanine increased the organoid budding rates(P=0.001)and the budding height of the crypt significantly(P=0.004).In conclusion,β-alanine can improve intestinal morphology and barrier function,reduce inflammatory responses and alleviate the adverse effects of weaning stress on piglet intestinal health.