Mechanism of signal transduction in distant organ injuries induced by intestinal ischemia/reperfusion / 中华临床营养杂志

Objective To investigate the effect of different antibodies on Toll-like Receptor 4-High Mobility Group Box 1 and its downstream signal transductions in distant organ injuries caused by intestinal ischemia/reperfusion in mice.Methods A total of 40 mice (C57BL/6,SPF level) were by random number table method assigned into five groups:sham,control,anti-HMGB1,anti-Myeloid differentitation gene,and antiTIR domain containing adaptor inducing IFN-β (n=8).In the control,anti-HMGB1,anti-MyD88,and antiTRIF groups,the IgG,HMGB1,MyD88,and TRIF antibodies were injected,respectively,via the tail vein 30 minutes before ischemia (1 mg/kg body weight,0.025％).After anesthesia and abdomen incision,all mice,except the sham group,underwent intestinal ischemia by clamping the superior mesenteric artery for 60 minutes followed by 60 minutes of reperfusion.Sham group underwent the same surgical procedures except for clamping the artery.Serum nuclear factor-κB p65,Interleukin-6 and Tumor Necrosis Factor-α were measured.Morphological changes in the lung and intestine were evaluated.mRNA and protein expressions of HMGB1 and NF-κB in lung and intestinal tissues were assayed.Results Compared with the control group [(228.53± 24.85),(104.91±31.18),and (70.81±46.97) ng/L],HMGB1 [(145.00±33.63),(62.28±6.73),and (52.76± 5.71) ng/L],MyD88 [(191.12± 13.22),(85.90± 17.37),and (63.19 ± 5.47) ng/L],and TRIF [(183.73±10.81),(78.14±7.38),and (59.70±4.63) ng/L] significantly decreased the serum level of NF-κB (P=0.000,0.005,0.001),IL-6 (P=0.000,0.004,0.000) and TNF-α (P=0.000,0.024,0.002) after ischemia reperfusion.Tissue injuries in the lung and intestine were also alleviated by HMGB1,MyD88,and TRIF.The anti-HMGB1,anti-MyD88,and anti-TRIF groups displayed significant elevations of HMGB1 mRNA [lung (1.89±0.18),(2.35±0.31),and (2.29±0.28),ileum (4.93±0.55),(5.96± 0.73),and (5.76±0.51)],NF-κB mRNA [lung (1.42±0.23),(1.77±0.18) and (1.70±0.13),ileum (2.23±0.55),(3.11±0.38) and (2.99±0.24)] and NF-κB protein expressions in lung and ileum tissues compared to the sham group [lung HMGB1 mRNA (1.04±0.19) (P=0.000,0.000,0.000),NF-κBmRNA (1.03±0.21) (P=0.004,0.000,0.000),ileum HMGB1 mRNA (1.14±0.54) (P=0.000,0.000,0.000),NF-κB mRNA (1.03±0.23) (P=0.000,0.000,0.000)].However,incornparison with the control group [lung HMGB1 mRNA (2.67±0.23) (P=0.000,0.035,0.016),NF-κB mRNA (2.04±0.29) (P=0.000,0.039,0.012),ileum HMGB1 mRNA (6.70±0.66) (P=0.001,0.038,0.015),NF-κBmRNA (3.71±0.53) (P=0.000,0.018,0.006)],the other three groups showed a significant down-regulation,with the most remarkable decrement in the anti-HMGB1 group.Application of anti-HMGB1,anti-MyD88,and anti-TRIF could drastically attenuate the tissue injuries in ischemia reperfusion.anti-HMGB1 exhibited the most significant effect.Conclusions HMGB1 and its downstream signals play an important role in intestinal ischemia reperfusion injuries in mice.Of two downstream signals,the TRIF-dependent pathway exerts a more important effect than that of the MyD88-dependent pathway.

Comparison of different analyzing methods for detection of free amino acids in plasma / 中华临床营养杂志

Objective To evaluate the accuracy of different methods in detecting free amino acids in plasma.Method 40 blood samples from healthy volunteers were analyzed by an automatic amino acid analyzer ( Li+system) and the results compared with previous reports using other analyzers.Results The results ob-tained by this analyzer for major amino acids [asparagine (Asn), glutamic acid (Glu), glutamine (Gln), valine (Val), tyrosine (Tyr), phenylalanine (Phe), ornithine (Orn), arginine (Arg)] were similar with those previously reported using other amino acid analyzers ( all P>0.05 ) and liquid chromatography tandem-mass spectrometry (LC-MS/MS) (all P>0.05).Except for Glu and Tyr, the results for major amino acids showed large deviation compared to the results from high performance liquid chromatography ( HPLC) ( all P<0.05).Conclusion The amino acid analyzer (Li+) and LC-MS/MS (iTRAQ kit) could accurately detect free amino acids in plasma.

Establishing Physiological Body Fluid Method to Evaluate the Normal Value of Plasmic Free Amino Acid in Normal Healthy Volunteers / 现代检验医学杂志

Objective To analyze the plasma amino acid levels and evaluate the free amino acids value of normal healthy volun-teers in plasma by establishing physiological fluid method.Methods ①Establishment of methodology:including repeatabili-ty of blood sample,recovery rate,linearity,and stability;②The free amino acid values in plasma in 40 normal healthy volun-teers were analyzed.Results With the standard solution of different concentrations (2,4 and 8 nmol)analyzed and linear re-gression of amino acid calculated,found that R2 of all the amino acids were within the range from 1 to 0.9 9 9.The repeatabili-ty with in batch and between batches of different amino acid in blood samples were respectively 0.30~2.90 (rsd)and 0.40~5.16(rsd);recovery rates were 93.1%~107.4%.Then evaluated the normal values of plasma amino acid in 40 healthy volunteers (male vs female:1 vs 1 ),and compared the results with that measured by other instruments.Conclusion With lithium citrate buffer system to analyze the free amino acid in blood samples,it displayed good reproducibility,recovery rate, linearity and stability.Comparison of different instruments measuring the free amino acids in plasma of normal healthy vol-unteers showed good agreement,confirming that the method of physiological fluid analysis is reliable.

The role of high mobility group box 1 in the signaling pathways of mouse intestinal ischemia-reperfusion injury / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the role of high mobility group box 1 (HMGB1) in the signaling pathway of mouse intestinal ischemia-reperfusion injury.</p><p><b>METHODS</b>Twenty-four Specific Pathogen free male C57BL / 6 mice were randomly divided into three groups (n = 8) : the sham operation group (sham), the control group(control) and the HMGB1 antibody group (anti-HMGB1). The vehicle alone or anti-HMGB1 antibody(1 mg/kg, 0. 025%) was injected respectively via the caudal vein 30 min prior to ischemia in the control group or the anti-HMGB1 group. All mice were anesthetized,opened abdominal wall and exposed arteria mesenterica superior. The control group and the anti-HMGBl group underwent 60 min of mesenteric ischemia and 60 min of reperfusion and the sham group were merely opened abdominal wall for 120 min without ischemia-reperfusion. The levels of NF-κB p65, IL-6 and TNF-α in plasma and the activity of MPO in lung and liver and the morphological changes of lung and intestinal tissue were measured. The mRNA levels of HMGB1 and NF-κB were evaluated using real-time quantitative PCR and the protein levels of HMGB1 and NF-KB were evaluated using Western blot. The experimental data was analyzed using one-way analysis of variance.</p><p><b>RESULTS</b>The levels of IL-6, TNF-α and NF-κB p65 in plasma was significantly higher in the control group and the anti-HMGB1 group compared with the sham group (the sham group vs. the control group vs. the anti-HMGB1 group, NF-κB p65, 104. 64 ± 11. 89: 228. 53 ± 24. 85: 145. 00 ± 33. 63, F = 38. 036, P <0. 05; IL-6,50. 02 ± 6. 33:104. 91 ± 31. 18:62. 28 ± 6. 73, F = 49. 763, P < 0. 05; TNF-α, 43. 79 ± 4. 18: 70. 81 ± 6. 97: 52. 76 ± 5. 71, F = 34. 571, P < 0. 05). The increasing degree in the anti- HMGB1 group was significantly reduced compared with the control group (P <0. 05). The activity of MPO of liver and lung in the control group and the anti-HMGB1 group was significantly higher than those in the sham group (P <0. 05). Compared with the sham group, the degree of tissue injury in jejunum, ileum and lung was serious in the control group, and that in the anti-HMGB1 group was significantly lower than the control group. The expression of HMGB1 mRNA and NF-κB mRNA in the lung and the ileum in the sham group and the control group were all higher than the sham group (HMGB1 mRNA in lung: sham group 1. 04 ± 0. 19 vs. control group 2. 25 ± 0. 18 vs. anti-HMGB1 group 1. 89 0. 18, F = 66. 203, P < 0. 05; in ileum: 1. 14 ± 0. 54 vs. 6. 26 ± 0. 60 vs. 4. 93 0. 55, F = 133. 427, P < 0. 05; NF-κB mRNA in lung: 1. 03 ± 0. 21 vs. 2. 04 ± 0. 29 vs. 1. 42 ± 0. 23, F =26. 229, P < 0. 05; ileum: 1. 03 ± 0. 23 vs. 3. 71 ± 0. 53 vs. 2. 23 ± 0. 55, F = 50. 477, P <0. 05). Subjected to intestinal ischemia-reperfusion injury, the protein expression of HMGB1 and NF-κB in the lung, jejunum and ileum in the control group and the anti-HMGB1 group increased compared with the sham group(P <0. 05), but that was significantly lower in the anti-HMGB1 group than the control group (P <0. 05).</p><p><b>CONCLUSION</b>The administration of anti-HMGB1 antibodies may reduce the damage caused by ischemia-reperfusion effectively.</p>

The effects of lymph after intestinal ischemia/reperfusion on the inflammatory factors and Toll-like receptor 4 ligand high mobility group box-1 in Toll-like receptor 4 deficient mice / 中华临床营养杂志

Objective To investigate the effects of lymph from ischemic/reperfused intestine on the inflammatory factors and Toll-like receptor 4 (TLR4) ligand high mobility group box-1 (HMGB1) in TLR4 deficient (TLR4-/-) mice.Methods A total of 20 SD rats weighing (300 ±20) g were randomly assigned into two groups:lymph drainage group (group N,lymph drainage for 180 minutes without other treatment) and intestinal ischemia/reperfusion group (group I/R,draining the lymph for 180 minutes while clipping the superiormesenteric artery for 60 minutes followed by 120-minute reperfusion).Thirty-two TLR4-/-mice and thirty-two C57BL/6 wild type (WT) mice were each divided into 4 sub-groups (n =8),injected with different fluids through the caudal vein:group N with normal lymph;group I/R with I/R lymph;group Edt with endotoxin;group HMGB1 with HMGB1 protein.The mice were sacrificed 180 minutes after the injection for sample collection.Results The levels of endotoxin and HMGB1 in the lymph drainage of the group I/R rats were significantly higher than that of the group N rats [(0.034 ± 0.050) Eu/ml vs.(0.017 ± 0.023) Eu/ml,P =0.033;(4.293 ± 0.883) ng/ml vs.(0.509 ± 0.128) ng/ml,P =0.006].In the mice injected with HMGB1,the mucosa thickness and villus height in the ileum of the WT mice were significantly lower than that of the TLR4-/-mice [(335.8±43.2) μmvs.(602.1±37.5) μm,P=0.000;(273.0±31.7) μm vs.(404.5 ± 18.6) μm,P =0.000];in both WT and TLR4-/-mice injected with the I/R lymph drainage,the mucosa thickness and virus height were decreased,but the decrements were significantly lower in TLR4-/-mice;there were no statistically significant differences in the levels of interleukin-6 (IL-6),tumor necrosis factor-α (TNF-α),endotoxin,and HMGB1 between the TLR4-/-and the WT mice injected with normal lymph or endotoxin.In the mice injected with I/R lymph drainage,the levels of inflammatory factors in the TLR4-/-mice were significantly lower than those in the WT mice [TNF-α:(28.637 ±5.166) pg/ml vs.(41.917 ±8.175) pg/ml,P=0.000;IL-6:(60.900 ±24.729) pg/ml vs.(110.265 ±28.545) pg/ml,P =0.000].In the mice injected with HMGB1,the levels of inflammatory factors in the TLR4-/-mice were significantly decreased compared with those in the WT mice [TNF-α:(20.865 ± 6.464) pg/ml vs.(31.059 ± 6.204) pg/ml,P=0.004;IL-6:(36.268 ±8.977) pg/ml vs.(76.677 ± 14.099) pg/ml,P=0.000].Conclusions The concentrations of endotoxin and HMGB1 are significantly increased during intestinal I/R in rats.After injection of I/R lymph drainage,endotoxin,and HMGB1,the levels of inflammatory factors and HMGB1 in the mice injected with I/R lymph drainage are significantly higher than those in the mice injected with normal lymph;the levels of inflammatory factors and local damage of intestinal mucosa are significantly reduced in the TLR4-/-mice than in the WT mice.The gut-lymph pathway may play a key role in the intestinal I/R injury.

A multicenter cross-sectional survey on the use of parenteral nutrition in hospitalized patients in Beijing / 中华临床营养杂志

Objective To investigate the use of parenteral nutrition in hospitalized patients and to examine the process of care of patients receiving parenteral nutrition (PN) in hospital, in light of European Nutrition Day study, and to preliminarily explore the possible main risk factors for complications.Methods We recruited 314 adult hospitalized patients (≥18 years) requiring PN on a predetermined day (November 25, 2013) in 6 hospitals in Beijing and investigated their disease status, nutrition risk, the use of PN and venous infusion related complications using the European Nutrition Day survey questionnaire.Results Of the 314 patients, 311 completed the survey.In the 311 patients, the proportion of patients who received PN of all-in-one mixed preparation was 76.2％ (237/311), the proportion of patients receiving multibottle system was 23.8％ (74/311);PN was administered via central vein in 56.8％ (171/301) of the patients and via peripheral veins in 43.2％ (130/301) of the patients.The mean duration of infusion was (12.5 ±5.1) hours.The ratio of glucose to fat was 0.84 and the ratio of non-protein to calories 531.1.The total energy provision was less than the recommended intake.38.6％ (120/311) of the patients reported that PN infusion would affect activity, and 33.4％ (104/311) thought PN affected their sleep, and the incidence of infusion-related pain was 19.9％ (62/311).Multivariate analysis result showed that the most important factors of infusion-related pain were intravenous route of PN (x2 =25.911,P =0.000) and total venous infusion volume (x2 =6.053, P =0.014).Conclusions The total energy provision of PN is generally inadequate in hospitalized patients in Beijing.The key factor for reducing transfusion-related pain and enhancing PN tolerance is to establish appropriate infusion route.

Correlations among different measurement indicators of intestinal barrier / 中华临床营养杂志

Objective To study several measuring methods of the intestinal mucosa barrier and evaluate the correlation between different methods for determining the intestinal damage.Methods Sixteen specific pathogen free (SPF) male Sprague-Dawley rats were randomly divided into two groups:the Control group (n =8) and the ischemia/reperfusion (I/R) group (n =8).After adaptive feeding for 5 days,I/R group was put into ischemia model for 60 min and the Control group was merely opened on its abdominal wall but without ischemia for 60 min.After having been fed for another day,all rats were killed and specimens were collected.The plasma diamine oxidase (DAO),D-lactate (D-LAC),endotoxin,and glutamine (Gln) levels were detected,and the intestinal mucosal morphology was observed.The intestinal permeability (L/M) was detected 1 day before and after the surgery.Results The plasma DAO,D-LAC,and endotoxin levels were significantly higher in I/R group compared with the Control group (DAO:(0.498 ±0.032) vs (0.247 ±0.051) U/ml,t=-11.790,P=0.000; D-LAC:(5.47±1.55) vs (3.83±0.63) mg/L,t=-2.757,P=0.022; endotoxin:(0.0395±0.002 8) vs (0.025 6 ±0.004 5) EU/ml,t =-7.377,P =0.000).The plasma Gln concentration was significantly lower than that in the Control group [(646.12 ± 34.75) vs (839.13 ± 163.76) μmol/L,t =3.261,P =0.012).The L/M value on the 1 st postoperative day was significantly higher than that in the I/R group [(3.63 ±2.09) vs (1.22 ±0.66),t =-3.118,P =0.013)].The jejunum mucosal thickness,jejunum villus height,ileal mucosal thickness,and ileal villus height were significantly lower in I/R group compared with the Control group after operation [(329.80 ±64.68) vs (512.82 ±38.41) μm,t=6.881,P=0.000; (253.06±69.33) vs (386.79±56.39) μm,t=4.232,P=0.001; (205.89± 18.71) vs (335.29±27.71) μm,t=10.945,P=0.000; (135.61 ±22.30) vs (253.18±31.02) μm,t =8.705,P =0.000].After intestinal ischemia/reperfusion,DAO,D-LAC,endotoxin and L/M were all increased and positively correlated with each other.The plasma concentration of Gln and the morphological changes of jejunum and ileum were negatively correlated with DAO,D-LAC,endotoxin,and L/M,respectively.Conclusions After intestinal ischemia/rcperfusion,the levels of all examination indicators obviously change and correlate with each other.The DAO,D-LAC,endotoxin,and L/M are positively related to each other and negatively correlated with the intestinal barrier function.Gln is positively correlated with small intestinal mucosal morphology and negatively correlated with others,respectively.

Absorption and transport mechanism of small peptides and their physiological functions / 中华临床营养杂志

Small peptides is one of the main components in the final product of protein digestion in the gastrointestinal tract,which plays an important role in protein nutrition.Present studies show that small peptides in the intestine can be absorbed directly into the circulation,which is also the main form of protein absorption in vivo.However,the transporter system of small peptides is independent from that of amino acids.This paper elaborates on the absorption and transport system of small peptides,their advantages in enteral nutrition,and some small peptides with critical physiological functions.

Impact of intestinal ischemia/reperfusion on free amino acid levels in plasma / 中华临床营养杂志

Objective To investigate intestinal mucosal injury and the change of free amino acid levels in plasma with intestinal ischemia/reperfusion.Methods Twenty-four Sprague-Dawley (SD) male rats (SPF grade) were randomly divided into 3 groups with 8 rats in each group:Blank group,Sham group and ischemia/reperfusion (I/R) group.The rats in I/R group were subjected to 60 min ischemia by clamping the superior mesenteric artery (SMA),followed by 120 min repeffusion.All rats were sacrificed with blood withdraw through inferior vena cava.The plasma was precipitated with Sulfosalicylic acid and the supernatant free amino acid levels were measured and the intestinal mucosal thickness and villus length were also assayed.Results In the I/R group the total free amino acids,essential amino acids (EAA),glutamine and branched-chain amino acids (BCCA) were remarkably lower [the total free amino acids:I/R vs Blank vs Sham:(4585.1 326.1) vs (5661.5 ±581.9) vs (5337.9±998.7) μmol/L (F=5.075,P=0.016); EAA:I/Rvs Blank vs Sham:(1401.3 ±183.4) vs (2147.6 ± 265.1) vs (1796.2 ± 440.8) μmol/L (F =1 1.216,P =0.000) ; glutamine:I/R vs Blank vs Sham:(646.1 ± 34.7) vs (895.7 ± 258.8) vs (839.1 ± 163.7) μmol/L (F =4.326,P =0.027) ; BCCA:I/R vs Blank vs Sham:(507.8 ± 119.0) vs (912.2 ± 165.8) vs (671.9 ± 79.8) μmol/L (F =10.662,P =0.001)]and the jejunum and ileum mucosal thickness and villus height were decreased compared to Blank and Sham groups [jejunum mucosal thickness:I/R vs Blank vs Sham:(401.50 ± 117.79) vs (529.22 ±54.73) vs (499.54 ±64.48) μm (F=31.869,P =0.000) ; jejunum villus height:I/R vs Blank vs Sham:(271.37 ± 84.29) vs (365.26 ± 46.98) vs (349.67 ± 56.11) μm (F =30.472,P =0.000) ; ileum mucosal thickness:I/R vs Blank vs Sham:(254.20 ± 43.56) vs (324.70 ± 30.56) vs (298.26 ± 58.46) μm (F =30.442,P =0.000) ; ileum villus height:I/R vs Blank vs Sham:(169.37 ± 37.25) vs (221.62 ± 37.26) vs (193.25 ± 38.39) μm (F =24.145,P =0.000)],and The EAA and BCAA in the I/R group were lower than the Sham group (respectively,P ＜0.05).There was no significant difference in aromatic amino acids (AAA) among the three groups [I/R vs Blank vs Sham:(273.2 ± 37.4) vs (296.8 ± 55.6) vs (281.9 ± 7.3) μmol/L (F =0.578,P =0.570)].The ratio BCAA/AAA in the Sham and I/R groups were significantly lower than the Blank group [(I/R vs Blank vs Sham:(2.4 ±0.6) vs.(1.9 ±0.4) vs (3.1 ±0.7) (F =5.215,P =0.014)],while the I/R group was decreased slightly compared to the Sham group,but the difference was not significant (P ＞ 0.05).The ethanolamine phosphate,taurine,citrulline,cystine,phosphoserine levels were reduced in the Sham and I/R groups compared to the Blank group [ethanolamine phosphate:I/R vs Blank vs Sham:(11.4 ± 1.9) vs (14.3 ± 3.4) vs (10.1±1.7) μmol/L(F=5.897,P=0.009);taurine:I/R vs BlankvsSham:(341.1±36.3) vs(533.2±90.8) vs (439.2±105.4) μmol/L (F=10.702,P=0.001); citrulline:I/R vs Blank vs Sham:(57.7±3.2) vs (73.1 ±16.2) vs (58.1 ±3.8) μmol/L (F=6.360,P =0.007); cystine:I/R vs Blank vs Sham:(20.0 ± 3.6) vs (60.6 ± 24.6) vs (36.3 ± 5.8) μmol/L (F =15.344,P =0.000) ; phosphoserine:I/R vs BlankvsSham:(10.2±1.1) vs (15.8±5.4) vs (11.7 ±3.4) μmol/L (F=4.878,P=0.018)],and the taurine and cystine in I/R groups were significantly decreased than the Sham group (respectively,P ＜ 0.05).The ornithine and arginine were comparatively reduced in I/R in contrast to the Blank and Sham groups [ornithine:I/R vs Blank vs Sham:(81.5 ± 19.0) vs (125.5 ±42.3) vs (114.9 ± 19.5) μmol/L (F =4.961,P =0.017) ;arginine:I/R vs Blank vs Sham:(199.2 ± 8.0) vs (258.9 ± 14.6) vs (248.7 ± 38.4) μmol/L (F =13.940,P =0.000)].The tryptophan and glutamic acid concentrations were increased in the Sham and I/R groups [tryptophan:L/R vs Blank vs Sham:(125.9 ± 12.1) vs (103.1 ± 29.9) vs (128.9 ± 18.5) μmol/L (F =5.429,P =0.031) ; glutamic acid:I/R vs Blank vs Sham:(188.6 ± 29.8) vs (93.6 ± 29.4) vs (125.4 ± 43.8) μmol/L (F =15.241,P =0.000)] and it was lower in the Sham group than the I/R group (P ＜ 0.05).Conclusion Intestinal ischemia-reperfusion can cause intestinal mucosal injury and the change of free amino acid levels in plasma and intestinal barrier damage may be related to the decline glutamine concentration and the increase of protein catabolism.

Effects of ω-3 polyunsaturated fatty acids intervention on Toll-like receptor 4 and high mobility group box 1 with intestinal ischemia/reperfusion injury / 中华临床营养杂志

Objective To investigate the expressions of Toll-like receptor 4 (TLR4) and high mobility group box 1 (HMGB1) expression on distant tissue during the intestinal ischemia/reperfusion and the effects of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) intervention in rats.Methods Forty-eight Sprague-Dawley male rats,weighing (281.50 ± 22.68) g,were randomly divided into three groups (n =16) after gastrostomy:normal diet (N) group,enteral nutrition (EN) group and EN plus ω-3 PUFAs (PUFA) group.Each group was further divided into lymph drainage (I/R + D) and non-drainage (I/R) sub-groups (n =8 each) according to whether treated with intestinal lymph drainage.All the rats were subjected to 60 min ischemia by clamping the superior mesenteric artery,followed by 120 min reperfusion,while the rats in the I/R + D subgroups were treated with intestinal lymph drainage for 180 min at the same time.Results The interleukin-6 level in lymph in N (I/R + D) group was significantly higher than in the EN (I/R + D) and PUFA (I/R + D) groups (PUFA vs EN vs N:(154.57 ±69.30) ng/L vs (97.58 ±40.34) ng/L vs (85.35 ±23.93) ng/L,P =0.021).Besides,the serum level of HMGB1 in PUFA (I/R + D) group was significantly lower compared to the other 5 groups [PUFA (I/R) vs EN (I/R) vs N (I/R) vs PUFA (I/R + D) vs EN (I/R + D) vs N (I/R + D):(2.95 ± 1.17) μg/L vs (3.86 ±0.99) μg/L vs (4.45 ± 1.73) μg/L vs (1.71 ±1.41) μg/Lvs (2.11±0.56) μg/Lvs (3.13 ±0.79) μg/L,P=0.000],and it also decreased in the PUFA (I/R) and EN (I/R) groups than the N (I/R) group (respectively,P ＜ 0.05).Furthermore,the serum endotoxin level in PUFA (I/R) group was significantly lower compared to the N (I/R) and EN (I/ R) groups[PUFA(I/R) vsPUFA (I/R+D) vsEN (I/R) vs N (I/R):(0.020±0.004) EU/mlvs (0.028 ±0.006) EU/ml vs (0.028 ±0.005) EU/ml vs (0.018 ±0.006) EU/ml,P=0.014].Together the serum tumor necrosis factor-α level in both PUFA (I/R) and PUFA (I/R + D) groups were significantly lower than theEN (I/R),N (I/R) and N (I/R+D) groups [PUFA (I/R+D) vs PUFA (I/R) vs EN (I/R) vsN (I/R) vs N (I/R+D):(12.03 ±6.57) ng/L vs (14.32 ±6.11) ng/Lvs (23.27 ±15.60)ng/L vs (27.42 ± 10.37) ng/L vs (26.87 ± 5.30) ng/L,P =0.013].The jejunum and ileum mucosa in all the I/R groups showed swelling and atrophy and appeared fragile,while the PUFA groups showed less yellow staining and injury than the other two groups (P ＜ 0.05,respectively).In addition,the expressions of TLR4 mRNA in jejunum,ileum,and liver in all the drainage groups were respectively lower than the corresponding non-drainage groups [jejunum:PUFA (I/R) vs EN (I/R) vs N (I/R) vs PUFA (I/R+D) vs EN (I/R+D) vsN (I/R+D):2.32±0.62vs3.08±1.29vs3.50±2.44vs 1.62±0.79vs 1.67±1.11 vs 1.94±0.81,P=0.025; ileum:PUFA (1/R) vsEN (1/R) vsN (1/R) vs PUFA (1/R+D) vsEN (1/R+D) vs N (1/R+D):2.67±1.08 vs 5.22 ± 3.96 vs 6.95 ±4.92 vs 1.70±0.68 vs 1.80±0.29 vs3.68±1.47,P=0.012; liver:PUFA (1/R)vsEN (1/R)vsN (1/R)vs PUFA (1/R+D)vsEN (1/R+D)vsN (1/R+D):5.67 ±1.94 vs 7.50 ±3.89 vs 7.18 ±4.55 vs 1.70 ±0.86 vs 3.90 ± 1.95 vs 4.12 ±2.11,P =0.001],which was consistent with the reduction of HMGB1 and the decrease of nuclear factor-κB activity in intestine,liver,and lung (P =0.000).Conclusions Lymph drainage and ω-3 PUFAs intervention can reduce the production of HMGB1 and inflammation factors,inhibit the expression of HMGB1 and TLR4 mRNA,and thus alleviate distant tissue injury caused by intestinal L/R.

Impact of ischemic stroke on the intestinal barrier function in dogs / 中华临床营养杂志

Objective To explore the impact of ischemic stroke on intestinal barrier changes in dogs.Methods Totally 20 mongrel dogs were divided into 2 groups by random number table with 10 in each.Double silicone cylinders measuring 1.1 mm in diameter and 8 mm in length were placed into their internal carotid arteries in all dogs of group A.Group B served as a control group and received sham operation.Light microscopy was performed for morphological measurement of intestinal epithelial cell.Immunohistochemistry was used to analysis the changes of protein zonula occludens-1(ZO-1)localizing at tight junction of intestinal epithelial cells.Results Ischemic stroke was confirmed by cranial CT scanning in all dogs of group A.Compared with the test results in group B,the occludin and Zo-1 protein levels in group A were significantly lower than those in group B(occludin:0.20 ±0.01 vs 0.22 ±0.01,P =0.007; ZO-1:0.20 ±0.01 vs 0.22 ±0.02,P =0.008).The apoptotic index in group A was significantly higher than in group B(29.04 ± 3.79 vs 6.44 ± 1.24,P =0.002).There was a positive correlation between occludin and ZO-1(R =0.71,P =0.02),and the apoptotic index was negatively correlated with levels of occludin,ZO-1(R =-0.91,P =0.00; R =-0.77,P =0.01).Light microscopy showed that the dogs in group A had intestinal mucousal injuries while no obvious change was detected in group B.Conclusions Dogs with ischemic stroke tend to develop intestinal barrier dysfunction,during which the destruction of tight junction plays a key role.The up-regulated apoptosis of intestinal epithelial cell constitutes one of the cellular bases of intestine injury.

Gut immunologic mechanism in the improvement of clinical outcome by enteral nutrition / 中华临床营养杂志

As the largest protective barrier of the body,gastrointestinal tract helps the organism resist the invasion and attacks of harmful substances from the outside world.There are three kinds of protective barriers:mechanical barrier,biotical barrier,and immune barrier.In recent years,increasing researches indicate the importance of gastrointestinal immune barrier and the important immunologic mechanism of enteral nutrition in improving the clinical outcome.This article reviews the effect of gut immunity in the improvement of clinical outcome by enteral nutrition.

The effect of murine intestine ischemia-reperfusion on endogenous ligand of TLR4 expression in distant organs / 中华普通外科杂志

Objective To investigate the expression of high mobility group box 1 (HMGBI) of TLR4 endogenous ligand and distant organ tissue injury after intestine ischemia/reperfusion and drainage of lymph fluid in rats. Methods Twenty-four Sprague-Dawley (SD) male rats (SPF grade) were evenly divided into 3 groups:Sham surgery group,intestine ischemia-reperfusion (I/R) group,and intestine ischemia-reperfusion with drainage of intestine lymph fluid (IR + drainage) group.The injury of distant organs such as lungs,liver,kidney was evaluated;The expression of high mobility group box 1 (HMGBI) of TLR4 endogenous ligand in intestine,lung and liver after the ischemia-reperfusion injury was measured by immunohistochemistry.Result HE stained sections,as well as HMGB1 immunohistochemistry results showed that the injury of ischemia/reperfusion (I/R) group and ischemia/reperfusion (I/R) + drainage group were more severe than that in the sham group.A large number of cells stained in I/R group,indicating that HMGB1 expression increased.The injury in I/R + drainage group was significantly less severe than I/R group.Western blot tests showed that the expression of HMGB1 in jejunum,ileum,liver,lung increased significantly in I/R group after L/R injury.Gray-scale values of HMGB1/β-actin were 0.3145 ± 0.0549、 1.7352 ± 0.3280、1.4443 ± 0.0926、3.1382 ± 0.4202.Lymph drainage significantly alleviated the damage,the expression of HMGB1 were significantly lower (P ＜0.05).Gray-scale values of HMGB1/β-actin were 0.1745 ± 0.0327、 1.1083 ± 0.2098、 1.1862 ± 0.1221、2.1095 ± 0.1993. Conclusion Increased expression of HMGB1 of TLR4 endogenous ligand is associated with intestinal and distant tissue injury during intestinal ischemia-reperfusion injury.Drainage of lymph fluid can block the gutlymph pathway and thus reduce the source of HMGB1 from the intestinal as well as the injury of distant tissue.

Effect of ω-3 polyunsaturated fatty acids on intestinal ischemiareperfusion injury and lymphatic duct ligation / 中华临床营养杂志

Objective To investigate the effect of intestinal lymphatic duct ligation and ω-3 polyun saturated fatty acids on intestinal and distant organ in intestinal ischemia-reperfusion injury. Methods Totally 40Sprague-Dawley (SD) male rats (SPF grade)after gastrostomy were equally randomized into sham group (Sham), enteral nutrition (EN) group, enteral nutrition and lymphatic duct ligation (EN + L) group, ω-3 polyunsaturated fatty acids (ω-3PUFA) group, and ω-3PUFA and lymphatic duct ligation (ω-3PUFA + L) group. After 7 days of nutritional intervention, rats were subjected to 60 minutes of intestinal ischemia, ischemia plus mesenteric lymph duct ligation, or sham procedures. After 3 days of continuous nutrition intervention using the original nutrient, lymph nodes, lung, intestine, liver, and blood specimens were harvested. Intestinal permeability and morphology, results of bacterial cultures, and serum cytokines were observed or detected. Result After 3 days of intestinal ischemia-reperfusion (I/R), the body weights of rats in EN group significantly decreased when com pared with the pre-I/R levels (P ＜ 0.05), while the body weights of rats in EN + L group were significantly lower than those in ω-PUFA group and ω-PUFA + L group (P ＜ 0. 05). After one day of intestinal ischemia-reperfusion (I/R), the L/M significantly increased in each group (P ＜0.05 or P ＜0. 01). After 3 days of intestinal ischemiareperfusion (I/R) , the L/M were significantly lower than the level one day after ischemia- reperfusion in EN + L group, ω-PUFA group, and ω-PUFA + L group (P ＜ 0.05). The L/M in EN group and EN + L group were significantly higher than that in ω-PUFA + L group (P ＜ 0. 05). The mucosa thickness and villus height of jejunum in ω-PUFA group and ω-PUFA + L group were significantly higher than those in Sham group, EN group, and EN + L group (P ＜ 0. 01 or P ＜ 0. 05). The mucosa thickness and villus height of ileum in ω-PUFA group and ω-PUFA +L group were also significantly higher than those in EN group (P ＜ 0.05). In ω-PUFA + L group, the serum endotoxin level and tumor necrosis factor-α level were significantly lower than those in EN group (P ＜ 0.05), interleukin (IL) -6 level was significantly lower than that in the ω-PUFA group (P ＜ 0.05), and IL-1 β level was significantly lower than those in other groups (P ＜ 0. 05). In EN group, the lung cell apoptosis index was significantly higher than those in other groups (P ＜ 0.05)and the levels of inducible nitric oxide synthase (iNOS)and myeloperoxidase (MPO) were significantly higher than those in ω-PUFA + L group (P ＜ 0. 05). The level of iNOS was also significantly higher in EN + L group than that in ω-PUFA + L group (P ＜ 0.05). Conclusions Sixty minutes of intestinal ischemia can cause intestinal injury, intestinal barrier dysfunction, and increased permeability of intestine. After 72 h of reperfusion, the intestinal injury can be partially recovered and the permeability can be lower than the post-ischemia level; however, bacterial endotoxin translocation and lung apoptotic cells still exist. Intestinal lymphatic ligation can alleviate the lung damage, promote repair of intestinal mucosa, reduce endotoxin translocation, and attenuate the systemic inflammatory response. EN added with ω-3PUFA is remarkably superior to conventional EN.

Role of Toll-like receptor 4 in intestinal ischemia-reperfusion and the interventional role of ω-3 polyunsaturated fatty acids / 中华临床营养杂志

Toll-like receptors is a super-family of pathogen recognition-receptors discovered in recent years.During the process of ischemia-reperfusion, the Toll-like receptor 4 (TLR4) combines with lipopolysaccharide and many endogenous ligands such as high mobility group protein B1, heparan sulfate, and fibrinogen. Through the myeloid differentiation protein 88 -dependent and -independent signaling pathways, the products induce the release of inflammatory cytokine-mediated inflammatory response, leading to injuries. ω-3 polyunsaturated fatty acids, by inhibiting the signal pathway activation and target gene expression of TLR4, can influence the function of many immune cells and regulate the body's inflammatory response and immune function. This article reviews the function of TLR4 during ischemia-reperfusion injury and the possible interventional role of ω-3 polyunsaturated fatty acids.

Change of high mobility group box 1 and effect of drainage of intestine lymph fluid on rat gut barrier during intestine ischemia-reperfusion / 中华临床营养杂志

Objective To investigate the change of high mobility group box 1 ( HMGBI ) after intestine ischemia reperfusion (I/R) in rats, compare the effect of drainage of intestine lymph fluid on gut barrier, and ex- plore the possible mechanism of iachemia-reporfusion injury. Methods Thirty-two Sprague-Dawley (SD) rats (SPF grade) were randomly divided into4 groups with 8 rats in each group: blank group, sham group, intestine is-chemia-reperfusion (I/R) group, and intestine ischemia-reperfusion with drainage of intestine lymph fluid (I/R +drainage) group. Indicators of gut barrier function damage, translocation of endotoxin, and change of HMGB1 and cytokines were detected after intestine ischemia-reperfusion injury. Results The gut barrier function damage and levels of endotoxin, HMGBI, tumour necrosis factor-alpha ( TNF-α), interleukin-6 ( IL-6 ), interleukin-1 beta (IL-1β), and soluble intercellular adhesion molecule-1 (sICAM-1) were significantly lower in blank group and sham group than in I/R group and I/R + drainage group ( P < 0. 05 ). Compared with the intestine I/R + drainage group, the levels of endotoxin and cytokines were significantly higher in the intestine I/R group. The level of HMGB1 was slightly higher than that in the intestine I/R + drainage group, but such difference was not statistically significant ( P > 0. 05 ). lmmunohistochemical staining also revealed that the expression of HMGB1 was significant- ly higher in I/R group than in I/R + drainage group. Conclusions Intestine iachemia-reperfusion injury can lead to the injury of intestine mucosal barrier and increase HMGB1 level HMGB1 may deteriorate gut barrier function and increase the leveh of systemic cytokines. Drainage of lymph fluid can block the gut-lymph pathway and thus decrease the levels of endotoxin and cytokines in systemic circulation and attenuate intestine ischemia-reperfusion injury.

Effect of Toll like receptor 4 and its endogenous ligands in ischemia-reperfusion injury / 基础医学与临床

TLR4 mediates I/R injury involving endogenous ligands.Interaction of TLR4 with endogenous ligands provides a critical link between tissue damage and activation of the innate immune response.In the early phase of liver,kidney,heart,or lung I/R injury,endogenous ligands are secreted from several kinds of cells,they are recognized by TLR4.Interaction of TLR4 with endogenous ligands,such as HMGB1,seems to be the most important trigger of inflammation and initiates signaling cascades leading to inflammatory and immune responses.Blocking the interaction of TLR4 with endogenous ligands may be useful in clinical management of inflammation and cellular necrosis caused by ischemic insults.

In vivo quantitative measurement of glutamate & glutamine in zelanian rabbits' muscle using MRS / 基础医学与临床

Objective Use MRS technology to detect in vivo Glx concentration of Zelanian rabbits' muscle.Methods Tweenty Zelanian rabbits are collected,SS-PRESS sequence is applied to check their Signal Ratio of Glx/TCr.After deta collection,draw blood and do the biopsy of the FOV's muscle tissue immediately.Mensurate the rabbits' blood Crn concentration,Glx and TCr concentration in muscle.Research the correlation between the above factors,attempt using the MRS Glx/TCr Signal Ratio and blood Crn concentration to predict muscular Glx concentration.Results The correlation between MRS Glx/TCr Peak Ratio and muscular Glx/blood Crn concentration ratio is 0.681.A linear regression formula is obtained: The predict Value of Glx concentration in muscle(?mol/g muscle)= Glx/TCr Peak Ratio ? Crn concentration in blood(mg/dl)?28.754-0.631.Conclusion Using a linear regression formula to predict the muscular Glx concentration,the results can reflect the level of the true values without biopsy,though it's not accurate enough for quantitatively analysis.

The effects of glutamine dipeptide on the improvement of endotoxemia in severely burned patients / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the influence of glutamine dipeptide on the plasma endotoxin levels in severely burned patients.</p><p><b>METHODS</b>Thirty burned patients with TBSA of 30 - 70% and III degree burn area more than 20% were randomly divided into control (C) and study (S) groups. Glutamine dipeptide powder in dose of 0.5 g/kg/day was given orally in bolus to those patients in S group during 1 - 12 postburn days (PBDs). The plasma levels of glutamine were determined during 1 - 12 PBDs. Simultaneously, the plasma endotoxin level was detected on 1, 3, 6 and 12 PBDs. The wound healing rate at 30 PBD and total hospital stay days were recorded.</p><p><b>RESULTS</b>The plasma glutamine levels at 1 PBD in C and S groups were obviously lower than normal level (659.5 +/- 35 micromol/L), but there was no difference between these two groups (P > 0.05). The plasma glutamine levels in C group was much lower than that in S group at 12 PBD (P < 0.05). The plasma endotoxin concentration on 1 PBD in these two groups increased evidently compared with the normal value (P < 0.05), and there was no difference between the two groups (P > 0.05). The plasma endotoxin level in S group was much lower than that in C group on 3 PBD (P < 0.05). As for the wound healing rate at 30 PBD, it was markedly higher in S group than that in C group (91% vs 85%). On the other hand, the hospital stay days in S group were evidently lower than that in C group (52 vs 67).</p><p><b>CONCLUSION</b>Oral intake of glutamine dipeptide in burn patients could be beneficial to the maintenance of the plasma concentration of glutamine and in decreasing plasma endotoxin level. It would also enhance the wound healing rate at 30 PBD and shorten the hospital stay days.</p>

Changes of intestinal permeabiloty of postoperative fasting patients / 临床外科杂志

Objective To measure intestinal permeability of postoperative fasting patients and evaluate their intestinal barrier function.Methods Twenty patients after moderate or minor operation ,10 male and 10 female,were included in the study .After 3 to 5 days of fasting,when their bowel functon returned to normal,10 ml solution of lactulose(2g) with mannitol (1g) were given orally,urine of 6 hours was collected.As a control group,20 healthy volunteers were also included.There were no statistical differences in sex and age between two groups.Results The L/M of the patients and healthy volunteers were 0.1989?0.1186 and 0.4398? 0.2165 respectively,the difference was significant.Conclusions The intestinal permenbility of postperative fasting patients was elevated when compared with that of volunteers.