Manganese methionine hydroxy analog chelated affects growth performance,trace element deposition and expression of related transporters of broilers

The present study aimed to evaluate the effects of manganese methionine hydroxyl analog chelated(Mn-MHAC)as a manganese(Mn)source on growth performance and trace element deposition in broilers.A total of 432 Arbor Acres commercial female broilers were fed a basal corn-soybean diet containing Mn at 25.64 mg/kg diet for 10 d.They were then randomly assigned to 6 groups,including a control group(the basal diet),a Mn sulfate group(the basal diet supplemented with Mn at 100 mg/kg diet),and 4 Mn-MHAC groups(the basal diet supplemented with Mn-MHAC at 25,50,75 and 100 mg Mn/kg diet,respectively).The results showed that compared with the control group,groups supplemented with Mn-MHAC had a positive effect on BW(quadratic,P=0.017)and ADG(quadratic,P=0.017).Moreover,the Mn-MHAC(50 mg Mn/kg diet)group had significantly greater BW and ADG(P<0.05)compared with the other Mn-MHAC groups.Trace element deposition results also showed that tibial Mn increased(linear or quadratic,P-0.002 and 0.009,respectively)in groups fed diets with increased levels of Mn-MHAC.In contrast,Fe deposition decreased both in the heart(linear,P-0.020)and tibia(P<0.05).In addition,the Mn-MHAC supplement noticeably lowered serum Mn-SOD activity(linear or quadratic,P-0.048 and 0.019,respectively).The relative mRNA levels of divalent metal transporter 1(DMT1)(P=0.024),ferro-portin 1(FPN1)(P=0.049),and Cu transporter-1(CTR1)(P<0.001)in the duodenum,as well as CTR1 in the jejunum and ileum(P=0.040 and 0.011,respectively)were higher in the Mn-supplemented group than in the control group.Furthermore,the relative mRNA level of DMT1 in the jejunum and ileum of broilers in the Mn-MHAC group(50 mg Mn/kg diet)did not differ from those in the control group,but was lower than those in the Mn sulfate group(P<0.05).In conclusion,Mn-MHAC dietary supplementation improved the growth performance and trace element deposition in broilers.From this study,we recommend the opti-mum Mn-MHAC level to meet the Mn requirement of broilers is 50 to 75 mg Mn/kg diet.

Kinetically inert manganese(II)-based hybrid micellar complexes for magnetic resonance imaging of lymph node metastasis

The localization and differential diagnosis of the sentinel lymph nodes(SLNs)are particularly important for tumor staging,surgical planning and prognosis.In this work,kinetically inert manganese(II)-based hybrid micellar complexes(MnCs)for magnetic resonance imaging(MRI)were developed using an amphiphilic manganese-based chelate(C18-PhDTA-Mn)with reliable kinetic stability and self-assembled with a series of amphiphilic PEG-C18 polymers of different molecular weights(C18En,n=10,20,50).Among them,the probes composed by 1:10 mass ratio of manganese chelate/C18En had slightly different hydrodynamic particle sizes with similar surface charges as well as considerable relaxivities(∼13 mM^(−1)s^(−1)at 1.5 T).In vivo lymph node imaging in mice revealed that the MnC MnC-20 formed by C18E20 with C18-PhDTA-Mn at a hydrodynamic particle size of 5.5 nm had significant signal intensity brightening effect and shortened T1 relaxation time.At an imaging probe dosage of 125μg Mn/kg,lymph nodes still had significant signal enhancement in 2 h,while there is no obvious signal intensity alteration in non-lymphoid regions.In 4T1 tumor metastatic mice model,SLNs showed less signal enhancement and smaller T1 relaxation time variation at 30 min post-injection,when compared with normal lymph nodes.This was favorable to differentiate normal lymph nodes from SLN under a 3.0-T clinical MRI scanner.In conclusion,the strategy of developing manganese-based MR nanoprobes was useful in lymph node imaging.