肠黏膜细胞的紧密连接与肠壁通透性的研究进展

肠黏膜细胞的紧密连接是构成肠黏膜屏障的重要结构基础,在调节肠黏膜通透性中发挥着重要的作用.其结构的破坏,可导致肠壁通透性增高,引起细菌移位、全身炎症反应及多器官功能受损.本文就肠黏膜紧密连接的结构和功能、与通透性的影响因素及改善措施进行了综述.     

Is type 2 diabetes due to a deficiency of FAD-linked glycerophosphate dehydrogenase in pancreatic islets?

The mitochondrial enzyme FAD-linked glycerophosphate dehydrogenase (m-GDH) is thought to play a key role in the glucose-sensing mechanism of the insulin-producing B-cell. It catalyses a rate-limiting step of the glycerol phosphate shuttle in pancreatic islets. Its activation by Ca²⁺ accounts for the preferential stimulation of oxidative glycolysis and, hence, pyruvate oxidation in glucose-stimulated islets. Reduced activity of m-GDH was recently observed in islet, but not liver, homogenates from rats injected with streptozotocin during the neonatal period and in two models of inherited diabetes, i.e. GK rats anddb/db mice. In the streptozotocin-injected and GK rats the m-GDH islet defect coincided, in intact islets, with an abnormally low ratio between oxidative and total glycolysis. Decreased activity of m-GDH in T-lymphocytes was also observed in 12 of 32 type 2 (non-insulin-dependent) diabetic patients, but only once among 26 other subjects including 11 healthy volunteers, 9 non-diabetics and 6 patients with either type 1 (insulin-dependent) or symptomatic diabetes. In the T-lymphocytes of type 2 diabetics the m-GDH deficiency occasionally coincided with an abnormally high ratio between glutamate-pyruvate and glutamate-oxaloacetate transaminase activities, as also observed in islets from streptozotocin-injected or GK rats. It is speculated that an islet m-GDH defect could represent a far from uncommon factor contributing to the pathogenesis of type 2 diabetes mellitus.     

Alcohol dehydrogenase： A potential new marker for diagnosis of intestinal ischemia using rat as a model

AIM: Intestinal ischemia (Ii) is an abdominal emergency due to blockade of the superior mesenteric artery resulting in 60-100% mortality if diagnosed late. Changes in several biochemical parameters such as D (-)-lactate, Creatinine kinase isoenzymes and lactate dehydrogenase suggested for early diagnosis, lack specificity and sensitivity. Therefore a biochemical parameter with greater sensitivity needs to be identified. METHODS: Wistar male rats were randomly assigned into two groups; control sham operated (n = 24) and ischemic test (n = 24) group. Superior mesenteric arterial occlusion was performed in the ischemic test group for 1 h. Alcohol dehydrogenase (ADH) was estimated in blood from portal vein, right ventricle of heart, dorsal aorta (DA) and inferior vena cava (IVC). The Serum glutamic acid pyruvate transaminase (SGPT) was also estimated in blood from portal vein and right ventricle of heart. RESULTS: A significant increase (P<0.001) in the levels of ADH in both portal blood as well as heart blood of the test group (232.72±99.45 EU and 250.85±95.14 EU, respectively) as compared to the control group (46.39±21.69 EU and 65.389±30.55 EU, respectively) were observed. Similarly, increased levels of ADH were observed in blood samples withdrawn from DA and IVC in test animals (319.52±80.14 EU and 363.90±120.68 EU, respectively) as compared to the control group (67.68±63.22 EU and 72.50±58.45 EU, respectively). However, in test animals there was significant increase in SGPT in portal blood (P= 0.054) without much increase in heart blood. CONCLUSION: Significant increase in the levels of ADH in portal and heart blood within 1 h of SMA occlusion without increase in SGPT in heart blood, suggests that the origin of ADH is from ischemic intestine and not from liver. Similarly, raised ADH levels were found in DA and IVC as well. IVC blood does represent peripheral blood sample. A raised level of ADH in test animals confirms it to be a potential marker in the early diagnosis of li.     

高氧对肠上皮细胞表达分泌片的影响

目的:研究高氧对肠上皮细胞分泌片(SC)表达的影响.方法:采用细胞计数和Giemsa染色方法检测不同氧浓度对细胞生长和细胞分裂能力的影响,采用免疫组织化学方法检测不同氧浓度对Caco-2表达SC的影响.结果:细胞计数显示400mL/L氧浓度利于细胞生长;600、900mL/L氧浓度导致细胞迅速死亡.不同氧浓度干预细胞3d细胞分裂指数有明显不同,分裂细胞百分数分别为正常氧浓度2.5;400mL/L氧浓度为3.3;600mL/L氧浓度为1.3;900mL/L氧浓度大部分细胞死亡.与正常氧浓度相比,氧浓度为400、600mL/L时SC表达增强,900mL/L氧浓度时SC表达明显减弱,甚为阴性,但600mL/L氧浓度SC表达较400mL/L氧浓度减弱.结论:适度的高氧促进细胞生长和促进肠上皮细胞表达SC,严重高氧则抑制肠上皮细胞SC表达及肠上皮细胞生长,肠上皮细胞SC表达增多有助于保护肠黏膜及平衡肠黏膜作用,阻滞细菌入侵肠道.     

冷-束缚应激诱导肠功能紊乱大鼠肠黏膜屏障变化的实验研究

目的 建立冷-束缚应激(CRS)诱导肠功能紊乱大鼠模型,探讨肠黏膜屏障变化在肠功能紊乱发病机制中的可能作用.方法 选取2个月龄Wistar大鼠40只,随机分成模型组和正常对照组.模型组采用寒冷加束缚为应激源实施干预,对照组不予任何干预.实验期间观察两组大鼠粪便性状,应用Bristol分型进行评分,通过直结肠扩张(CRD)实验测定内脏敏感性,取大鼠远端结肠及回肠黏膜行病理组织学检查.采用气相色谱法(GC)测定两组大鼠5 h尿液中乳果糖(L)与甘露醇(M)排泄率(L/M)比值,反映肠黏膜屏障的变化情况.结果 模型组粪便多为软的团块状或泥浆样,对照组多为柔软的香肠状或团块状,两组大鼠Bristol分型评分比较有显著性差异(P＜0.05);模型组初始感觉阈值、疼痛感觉阈值、最大耐受阈值分别较对照组显著降低(P＜0.05);两组肠黏膜病理检查均未见明显异常;模型组大鼠5 h尿液中L与M排泄率比值(L/M)较对照组显著增大(P＜0.05).结论 肠功能紊乱大鼠肠黏膜通透性增大,肠黏膜屏障受损可能与肠功能紊乱发病机制有关.     

Changes of neurotensin and endotoxin in rats with intestinal ischemia

AIM: To investigate the changes of neurotensin (NT) and endotoxin in rats with segmental intestinal ischemia. METHODS: The distal ileal mesenteric arteries in rats were ligated to make segmental intestinal ischemia models. At the 2^nd, 6^th and 12^th hours after intestinal ischemia, endotoxin levels in portal blood were tested by limulus lysate test and NT levels in plasma from the heart and in intestine tissues (ischemia and peri-ischemia areas) were assayed by radioimmunoassay. Histological changes of the mucosa were examined under light and electron microscopes. RESULTS: NT levels decreased significantly in intestinal ischemia and peri-ischemia areas (34.07 ± 5.93 vs 40.14 ± 5.38, P < 0.05; 7.47 ± 1.38 vs 40.14 ± 5.38, P < 0.01), especially lower in ischemia area (34.07 ± 5.93 vs 7.47 ± 1.38, P < 0.05. However, NT level increased obviously in plasma (0.76 ± 0.16 vs 0.47 ± 0.10, P < 0.05). Levels of endotoxin elevated obviously in portal blood (389.0 ± 105.0 vs 55.1 ± 6.7, P < 0.01), and the mucosa was injured both in ischemia and peri-ischemia areas. CONCLUSION: Intestinal ischemia injures intestinal mucosa and leads to decrease of intestinal NT level, which is accelerated by endotoxemia and increase of blood NT level.     

非侵入性方法检测肠黏膜屏障功能的研究进展

异常的肠道通透性在人类多种疾病中起着非常重要的作用,包括糖尿病、炎症性肠病、乳糜泻、多发性硬化、食物变态反应过敏症、肠易激综合征等.近年大量的研究发现:一些自身免疫性疾病伴有肠道通透性增加,这种现象发生在疾病之前,被认为与疾病的发病机制相关.研究肠黏膜屏障的功能与结构,可以提高我们对疾病的病因及病理生理认识,并且对于早期检测疾病以及对疾病进行二级预防有重要意义.目前有多种试验方法评估肠黏膜上皮细胞受损、紧密连接功能以及肠黏膜屏障的完整性.本篇综述主要探讨目前评估肠黏膜屏障功能的检测方法.     

肝硬化患者肠黏膜通透性与Child—Pugh分级的相关性研究

目的探讨肝硬化患者肠黏膜通透性（IP）与Child—Pugh分级的相关性及肠道去污剂对肝硬化患者肠道屏障功能及肝功能状态的影响。方法按Child—Pugh分级标准将76例肝硬化患者分为A、B、C3组,并选择30例体检者作为对照组,采用高压液相色谱法检测各组患者尿液乳果糖／甘露醇排出比（L／M）;给予76例肝硬化患者选择性肠道去污剂,比较用药前后各组患者肝功能Child—Pugh分级和肠黏膜通透性。结果肝硬化患者尿乳果N／甘露醇排出比明显高于对照组（0．208±0．025vs0．057±0．019）,肝硬化患者按Child。Pugh分级各组尿乳果糖／甘露醇排出比也均明显高于对照组,差异有显著性（P〈0．01）;采用Spearman等级相关分析发现,肝功能Child—Pu巾评分与乳果糖／甘露醇排出比呈正相关（r=0．658,P〈0．05）;给予肠道去污药物2周后肝硬化Child-Pugh分级各组患者尿液乳果糖／甘露醇排出比与治疗前比较均明显下降（P〈0．05）,各组Child—Pugh评分均有改善。结论肝硬化患者的肠黏膜通透性与肝功能Child—Pugh评分呈正相关,即肠道通透性随肝功能下降而升高,肠黏膜通透性对于肝硬化患者的诊断和治疗有临床意义。     

急性脑缺血后肠道血流灌注和动力的变化及其对肠黏膜屏障的影响

目的 探讨急性脑缺血后大鼠肠黏膜血流灌注和动力变化对肠黏膜屏障的影响. 方法雄性Wistar大鼠64只,随机分为急性脑缺血组(32只)和假手术对照组(32 只),两组大鼠分别按术后6、1 2、24和48 h时相点分为4个业组(每组均为8只),进行肠黏膜血流量、肠道传输系数、门静脉血内毒素水平以及多脏器组织匀浆中标记大肠杆菌移位率的检测. 结果 急性脑缺血组6、1 2、24和48 h时相点肠黏膜血流量分别为(34.5±3.2)PU、(22.7±1.9) PU、(26.2±4.3)PU和(30,5±4.1)PU,与对照组(46.8±5.4)PU、(50.1±3.6)PU、(45.4+4.1)PU、(48.7±7.3)PU比较,明显降低(t=2.650、2.875、2.639、2.507,均P＜0.05);肠道传输系数脑缺血组各时相点分别为0.59±0.07、0.48±0.06、0.50±0.08和0,57±0.04,均低于对照组0.73±0.04、0.75±0.02、0.74±0.06、0.76±0.03(t=2.409、2.758、2.649、2.807,均P＜0.05);脑缺血组损伤后6 h内毒素水平即开始升高,24h达到高峰.各时相点较对照组均明显升高(均P＜0.05).脑缺血组多脏器荧光标记大肠杆菌总检出率(11.4％、18.8％、25.0％、12.5％)明显高于对照组(2.1％、4.2％、2.1％、0％);内毒素水平与肠黏膜血流量和肠道传输系数呈显著相关性(r=-0.861、-0.7 96,均P＜0.05). 结论 急性脑缺血后早期肠黏膜通透性就已增高,而脑损伤大鼠肠黏膜血流、肠运动功能的下降是导致此病理生理变化的重要因素.     

IL-27在炎症性肠病炎症肠黏膜中的表达及意义

目的:检测克罗恩病(CD)和溃疡性结肠炎(UC)肠黏膜组织中IL-27 p28 mRNATL其蛋白、IL-27受体mRNA的表达,探讨其在CD和UC中的发病意义.方法:应用反转录-聚合酶链反应(RT-PCR)和蛋白质免疫印迹(Western blot)方法检测炎症性肠病患者炎症肠黏膜组织中IL-27 p28基因及蛋白、IL-27受体基因的表达,并与健康者作对照.结果:IL-27 p28 mRNA在CD患者中的阳性率和灰度分析表达较UC患者明显增高(X2=6.64,P<0.05;t=11.01,P<0.01),IL-27受体阳性率和灰度分析在CD患者较UC患者和健康对照者明显增高(阳性率:X2=10.91,P<0.016,X2=18.84,P<0.016).IL-27蛋白阳性率和灰度分析在CD患者中表达明显高于UC患者(X2=5.24,P<0.05;t=3.37,P<0.05),并且IL-27mRNA的表达与蛋白质表达密切相关.结论:IL-27 p28及其受体的上调,可能有助于CD患者炎症发展过程.     

人芽囊原虫感染致大鼠肠道紧密连接破坏的机制研究

目的 探讨大鼠感染人芽囊原虫后引起肠道屏障损伤的机制.方法 将30只SD大鼠随机分为对照组及感染1、3、6、9周组(感染组),每组6只.各感染组大鼠经口感染人芽囊原虫2×108个/鼠.对照组大鼠经口灌胃等体积磷酸盐缓冲液.分别于感染后1、3、6、9周收集7h大鼠尿液检测肠道通透性,随后采用颈椎脱臼法处死大鼠,取盲肠组织...     

Alterations in the colonic flora and intestinal permeability and evidence of immune activation in chronic constipation

BACKGROUND: Disturbances in bowel function in chronic constipation could result in changes in the colonic flora and lead to disordered immunity and to decreased resistance to pathogenic flora. AIM: To investigate systemic immunity, the faecal flora and intestinal permeability in patients with chronic constipation, under basal conditions and following therapy with the laxative Bisacodyl. METHODS: Intestinal permeability, faecal flora analysis, T- and B-lymphocyte numbers, T-cell subpopulations, lymphocyte proliferation, phagocytosis, intracellular killing of Staphylococcus aureus by neutrophils, as well as circulating levels of immunoglobulins, immune complexes and antibacterial antibodies were assessed in 57 patients with functional constipation. In 12 patients with severely delayed transit, investigations were repeated following therapy with Bisacodyl. RESULTS: Ovalbumin concentrations, in serum, were higher in constipated patients (28.2+/-4.1 ng/ml versus 1.0+/-0.4 ng/ml, p < 0.05). Elevated counts of CD3+, CD4+, CD25+ cells, increased spontaneous proliferation of lymphocytes, elevated titres of antibodies to Escherichia coli and S. aureus, diminished counts of CD72+ B cells, diminished lymphocyte proliferation under phytohemagglutinin (PHA) stimulation and a diminished phagocytic index for both neutrophils and monocytes were found in the constipated patients. Concentrations of Bifidobacterium and Lactobacillus were significantly lower in constipated patients; potentially pathogenic bacteria and/or fungi were increased. Therapy with Bisacodyl resulted in normalisation of the faecal flora, a reduction in ovalbumin concentration and return towards normal for certain immunologic parameters. CONCLUSION: Constipation is associated with striking changes in the faecal flora, intestinal permeability and the systemic immune response. Relief of constipation tends to normalise these findings suggesting that these changes are secondary to, rather than a cause of, constipation.     

Protective effects of terminal ileostomy against bacterial translocation in a rat model of intestinal ischemia/reperfusion injury

AIM: To investigate the effects of terminal ileostomy on bacterial translocation (BT) and systemic inflammation after intestinal ischemia/reperfusion (I/R) injury in rats.METHODS: Thirty-two rats were assigned to either the sham-operated group, I/R group, I/R + resection and anastomosis group, or the I/R + ileostomy group. The superior mesenteric artery was occluded for 60 min. After 4 h, tissue samples were collected for analysis. BT was assessed by bacteriologic cultures, intestinal permeability and serum levels of endotoxin; systemic inflammation was assessed by serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10, as well as by the activity of myeloperoxidase (MPO) and by intestinal histopathology.RESULTS: Intestinal I/R injury not only caused morphologic damage to ileal mucosa, but also induced BT, increased MPO activity and promoted the release of TNF-α, IL-6, and IL-10 in serum. BT and ileal mucosa injuries were significantly improved and levels of TNF-α and IL-6 in serum were decreased in the I/R + ileostomy group compared with the I/R + resection and anastomosis group.CONCLUSION: Terminal ileostomy can prevent the detrimental effects of intestinal I/R injury on BT, intestinal tissue, and inflammation.     

Transepithelial transport of putrescine across monolayers of the human intestinal epithelial cell line, Caco-2

AIM: To study the transepithelial transport characteristics of the polyamine putrescine in human intestinal Caco-2 cell monolayers to elucidate the mechanisms of the putrescine intestinal absorption. METHODS: The transepithelial transport and the cellular accumulation of putrescine was measured using Caco-2 cell monolayers grown on permeable filters. RESULTS: Transepithelial transport of putrescine in physiological concentrations (> 0.5 mM) from the apical to basolateral side was linear. Intracellular accumulation of putrescine was higher in confluent than in fully differentiated Caco-2 cells, but still negligible (less than 0.5%) of the overall transport across the monolayers in apical to basolateral direction.EGF enhanced putrescine accumulation in Caco-2 cells by four fold, as well as putrescine conversion to spermidine and spermine by enhancing the activity of S adenosylmethionine decarboxylase. However, EGF did not have any significant influence on putrescine flux across the Caco-2 cell monolayers. Excretion of putrescine from Caco-2 cells into the basolateral medium did not exceed 50 picomoles, while putrescine passive flux from the apical to the basolateral chamber, contributed hundreds of micromoles polyamines to the basolateral chamber. CONCLUSION :Transepithelial transport of putrescine across Caco2 cell monolayers occurs in passive diffusion, and is not influenced when epithelial cells are stimulated to proliferate by a potent mitogen such as EGF.     

酒精性肝炎小鼠肝肠组织变化与内毒素血症的关系探讨

目的酒精性肝病常伴发肠源性内毒素血症,但两者孰因孰果尚不明确。本研究的目的是探讨肠源性内毒素血症与酒精性肝病的关系。方法 20只C57BL/6小鼠被随机分为对照组和模型组,采用饲喂Lieber-Decarli无酒精和含酒精液体法制备酒精性肝炎模型。6周后取小鼠肝脏和结肠组织进行病理学观察;采用酶联免疫吸附法检测血清内毒素、二胺氧化酶和D乳酸含量;采用高效液相色谱法分析尿中乳果糖和甘露醇含量比值,以动态观察小鼠肠道通透性的变化。结果模型组动物肝细胞明显脂肪变,说明模型制备成功;模型组动物结肠粘膜变薄,萎缩,肠上皮细胞脱落,病理学评分(3.41±0.59)与对照组(2.36±0.43)比,差异有统计学意义(P=0.04);模型组和对照组动物血清内毒素水平分别为0.40±0.07Eu/L和0.14±0.03Eu/L(P=0.02),二胺氧化酶分别为4.17±0.88 U/mL和2.09±0.39U/mL(P=0.03),D乳酸分别为8.53±1.10mg/L和6.58±1.00mg/L(P=0.04),差异均有统计学意义;模型组小鼠1~6周末尿乳果糖/甘露醇(L/M值)排泄率分别是2.28±0.33(P>0.05)、2.55±0.40、2.49±0.18、2.51±0.55、2.46±0.59和2.59±0.44,对照组则分别是2.16±0.30、2.34±0.33、2.27±0.24、2.01±0.27、2.24±0.26和2.17±0.31,后5周两组比,均有显著性差异(P<0.05)。结论肠道通透性的增加早于肝脏损伤,肠道通透性增加引起的内毒素血症是酒精性肝炎的关键诱发因素。     

生长抑素预防猕猴肠缺血再灌注后的胰腺炎

目的观察肠缺血再灌注(intestinal ischemia reperfusion,IIR)对胰腺组织病理改变的影响及生长抑素(somatostatin,SST)的治疗作用。方法15只健康猕猴分为对照组、IIR组、SST组,每组5只。放免法检测外周血SST含量,酶比色法测定血清淀粉酶及脂肪酶,ELISA法检测血清及小肠黏膜组织IL-1β、IL-6、TNF-α水平,镜下观察胰腺组织病理变化。结果IIR组外周血SST为(62.17±13.56)pg/ml,较对照组的(160.61±33.84)pg/ml显著减少(P<0.05),血淀粉酶、脂肪酶、IL-1β、IL-6、TNF-α也均显著升高(P<0.05),胰腺组织出现病理性改变。SST组血SST水平为(156.32±30.25)pg/ml,较IIR组显著升高(P<0.05),血淀粉酶、脂肪酶、IL-1β、IL-6、TNF-α均明显下降(P<0.05),胰腺组织病理改变减轻。结论SST可预防IIR所导致的胰腺病理损伤。     

乳果糖降低非酒精性脂肪性肝炎患者肠道通透性及血清内毒素水平

目的探讨乳果糖对非酒精性脂肪性肝炎(non-alcoholic steatohepatitis,NASH)患者肠道通透性的干预作用。方法选择健康正常成人30例作为正常对照组(A组),非酒精性脂肪性肝炎共60例,随机分为NASH对照组(B组)和乳果糖干预组(C组)各30例,其中C组给予乳果糖(10 mL/d)进行干预。检测所有被研究者的血清内毒素、二胺氧化酶(diamine oxidase,DAO)、D-乳酸及ALT的浓度。干预4周后,再次检测B、C两组的血清内毒素、二胺氧化酶(DAO)、D-乳酸及ALT的浓度。结果与A组比较,治疗前B、C两组内毒素、DAO、D-乳酸水平显著增高(P<0.01),B组干预前后比较,内毒素、DAO、D-乳酸及ALT水平无显著改变(P>0.05),而C组干预前后比较,内毒素、DAO、D-乳酸及ALT水平显著降低(P<0.01)。结论 NASH患者血清内毒素水平及肠道通透性增高,乳果糖可降低NASH患者肠道的通透性及血浆内毒素水平。     

Effects of metformin on bile salt transport by monolayers of human intestinal Caco-2 cells

The antidiabetic biguanide metformin has been shown to increase faecal excretion of bile salts in type 2 diabetes. Cultured human intestinal Caco-2 cell monolayers provide a model of human enterocytes. These monolayers are used here to determine the effect of metformin on the secondary-active, sodium-linked transfer of ¹⁴C-glycocholate from the apical (brush border) to the basolateral (serosal) surface. During 24-h incubations, 10⁻² mol/l metformin significantly reduced ¹⁴C-glycocholate transfer. This could not be attributed to alterations of monolayer integrity or Na⁺-K⁺ ATPase pump activity. For example, the secondary-active transport of glucose and proline was not interrupted, and the inhibitory effect of metformin on bile salt transport was additive to the inhibitory effect of ouabain. The results suggest that metformin can act directly on intestinal enterocytes to reduce the active transfer of bile salts by a mechanism that is independent of Na⁺-K⁺ ATPase activity.     

Effect of dephytinization on bioavailability of iron, calcium and zinc from infant cereals assessed in the Caco-2 cell model

AIM： To test the effect of the dephytinization of three different commercial infant cereals on iron, calcium, and zinc bioavailability by estimating the uptake, retention, and transport by Caco-2 cells. METHODS： Both dephytinized （by adding an exogenous phytase） and non-dephytinized infant cereals were digested using an in vitro digestion protocol adapted to the gastrointestinal conditions of infants younger than 6 too. Mineral cell retention, transport, and uptake from infant cereals were measured using the soluble fraction of the simulated digestion and the Caco-2 cells. RESULTS： Dephytinization of infant cereals significantly increased （P 〈 0.05） the cell uptake efficiency （from 0.66%-6.05% to 3.93%-13%）, retention （from 6.04%-16.68% to 14.75%-20.14%） and transport efficiency （from 0.14%-2.21% to 1.47%-6.02%）, of iron, and the uptake efficiency （from 5.0%-35.4% to 7.3%-41.6%） and retention （from 4.05%-20.53% to 14.45%-61.3%） of zinc, whereas calcium only cell uptake showed a significant increase （P 〈 0.05） after removing phytate from most of the samples analyzed. A positive relationship （P 〈 0.05） between mineral solubility and the cell uptake and transport efficiencies was observed. CONCLUSION： Removing phytate from infant cereals had a beneficial effect on iron and zinc bioavailability when infant cereals were reconstituted with water. Since in developing countries cereal-based complementary foods for infants are usually consumed mixed with water, exogenous phytase additions could improve the nutritional value of this weaning food.