Intestinal development and growth performance of early-weaned piglets fed a low-threonine diet

High dietary threonine extraction by the digestive tract suggests that threonine contributes to maintain gut integrity. The aims of this study were to investigate the intestine development and the growth performance of early-weaned piglets pair-fed either a control well-balanced (C: 9.3 g threonine/kg diet) or a low-threonine diet (LT: 6.5 g threonine/kg diet) for 2 weeks. As expected, LT piglets presented lower plasma free threonine compared with C piglets (118 v. 356 ± 12 μmol/l, P < 0.001). Dietary threonine supply altered neither growth performance nor growth of the intestine and of the other portal-drained viscera (stomach, spleen and pancreas). Nevertheless, villus height was reduced in the ileum of the LT piglets compared with C piglets (446 v. 714 ± 74 μm, P < 0.05). This was also associated with a decrease in crypt width (P < 0.05) and villus height-to-crypt depth ratio (P < 0.05). Whereas maltase and lactase activities did not change between the two groups, aminopeptidase nitrogen activity was decreased in the ileum of LT piglets (269 v. 374 ± 27 IU/mg protein, P < 0.05). The number of mucin-containing goblet cells was not modified in the ileum and in the proximal part of the large intestine of the LT piglets compared with the C piglets. In conclusion, despite no alteration of intestinal growth, villus hypotrophy associated with a reduction of aminopeptidase nitrogen activity suggest an alteration of the structure of the ileum in early-weaned piglets fed a diet supplying inadequate dietary threonine.     

Epidermal growth factor improves intestinal morphology by stimulating proliferation and differentiation of enterocytes and mTOR signaling pathway in weaning piglets

Epidermal growth factor(EGF) has been shown to improve piglet intestinal morphology and epithelial recovery. In an attempt to further understand the mechanisms behind these improvements, this study tested the hypothesis that dietary EGF may affect intestinal morphology by stimulating the proliferation and differentiation of enterocytes in weaning piglets. In piglets receiving200 μg kg–1 EGF, crypt depth and villus height increased(P0.05). Adding 400 μg kg–1 EGF increased villus height-to-crypt depth ratio(P0.05), but reduced crypt depth(P0.05). Dietary supplementation with 200 μg kg–1 EGF significantly increased the number of Ki67-positive cells(P0.01) and tended to increase the mRNA level of proliferating cell nuclear antigen(P0.10).However, this supplementation decreased the expression level of intestinal fatty acid-binding protein(P0.05). Piglets fed with400 μg kg–1 EGF had an increased mRNA level of intestinal alkaline phosphatase(P0.05). The phosphorylation of m TOR(mammalian target of rapamycin) was observed in the 200 μg kg–1 EGF group. These results suggest that dietary supplementation with a low level of EGF improved piglet intestinal morphology through stimulating the proliferation and differentiation of enterocytes, and the mTOR signaling pathway may partly be involved in this process.     

Dietary supplementation with l-arginine or N-carbamylglutamate enhances intestinal growth and heat shock protein-70 expression in weanling pigs fed a corn- and soybean meal-based diet

This study determined effects of dietary supplementation with l-arginine (Arg) or N-carbamylglutamate (NCG) on intestinal health and growth in early-weaned pigs. Eighty-four Landrace × Yorkshire pigs (average body weight of 5.56 ± 0.07 kg; weaned at 21 days of age) were fed for 7 days one of the three isonitrogenous diets: (1) a corn- and soybean meal-based diet (CSM), (2) CSM + 0.08% NCG (0.08%), and (3) CSM + 0.6% Arg. There were four pens of pigs per diet (7 pigs/pen). At the end of a 7-day feeding period, six piglets were randomly selected from each treatment for tissue collections. Compared with the control group, Arg or NCG supplementation increased (P < 0.05): (1) Arg concentrations in plasma, (2) small-intestinal growth, (3) villus height in duodenum, jejunum and ileum, (4) crypt depth in jejunum and ileum, (5) goblet cell counts in intestinal mucosae, and (6) whole-body weight gain in pigs. Real-time polymerase chain reaction and western blotting analyses revealed that both mRNA and protein levels for heat shock protein-70 (HSP70) were higher (P < 0.05) in the intestinal mucosae of Arg- or NCG-supplemented pigs than in the control group. Furthermore, the incidence of diarrhea in the NCG group was 18% lower (P < 0.01) than that in the control group. Collectively, these results indicate that dietary supplementation with 0.6% Arg or 0.08% NCG enhances intestinal HSP70 gene expression, intestinal growth and integrity, and the availability of dietary nutrients for whole-body weight gain in postweaning pigs fed a CSM-based diet. Thus, Arg or NCG is a functional ingredient in the weaning diet to improve nutrition, health, and growth performance of these neonates.     

Dietary alanyl-glutamine improves growth performance of weaned piglets through maintaining intestinal morphology and digestion–absorption function

Alanyl-glutamine (Ala-Gln), a highly soluble and stable glutamine dipeptide, is known to improve gut integrity and function. The aim of this study was to evaluate whether dietary Ala-Gln supplementation could improve growth performance, intestinal development and digestive-absorption function in weaned piglets. A total of 100 purebred Yorkshire piglets weaned at 21 days of age were assigned randomly to four dietary treatment groups and fed a basal diet (control group) or a basal diet containing 0.15%, 0.30% and 0.45% Ala-Gln, respectively. Compared with the control group, piglets fed the Ala-Gln diets had higher average daily gain and lower feed : gain and diarrhea rate (P < 0.05). Moreover, dietary Ala-Gln supplementation increased villous height and villous height : crypt depth ratio in duodenum and jejunum (P < 0.05), as well as the activities of maltase and lysozyme in jejunum mucosa (P < 0.05). In addition, a decrease in serum diamine oxidase activity and crypt depth in duodenum and jejunum was observed in piglets fed the Ala-Gln diets (P < 0.05). Serum cytosolic phospholipase A2 (cPLA2) concentration and gene expression of cPLA2, Na⁺-dependent glucose transporter 1, glucose transporter 2 and peptide transporter 1 in jejunum were increased by feeding Ala-Gln diets relative to control diet (P < 0.05). These results indicated that feeding Ala-Gln diet has beneficial effects on the growth performance of weaned piglets, which associated with maintaining intestinal morphology and digestive-absorption function.     

刺五加提取物对早期断奶仔猪生长性能和血清生化参数的影响

早期断奶会使仔猪产生心理、环境和营养应激反应,引起仔猪腹泻、营养不良和生长迟滞等。本试验通过在日粮中添加刺五加提取物,饲喂21日龄断奶仔猪,观察其生长性能、腹泻指数、器官指数和血清生化参数等指标的变化,为开发绿色防病促生长剂提供理论依据。结果表明,刺五加提取物能够显著提高早期断奶仔猪的平均日采食量和平均日增重(P<0.05),降低料肉比,显著防治早期断奶仔猪腹泻(P<0.05),其作用强于粘杆菌素;刺五加提取物组第1周的α-淀粉酶、谷草转氨酶和谷丙转氨酶活性均大于对照组(P>0.05),第2周的尿素氮含量极显著大于抗生素组和对照组(P<0.01),碱性磷酸酶活性显著小于对照组(P<0.05),第4周的α-淀粉酶和脂肪酶活性显著大于对照组(P<0.05)。上述结果提示,刺五加提取物能够缓解仔猪的早期断奶应激,增强机体抵抗力,促进生长。     

Dietary supplementation with monosodium glutamate is safe and improves growth performance in postweaning pigs

Dietary intake of glutamate by postweaning pigs is markedly reduced due to low feed consumption. This study was conducted to determine the safety and efficacy of dietary supplementation with monosodium glutamate (MSG) in postweaning pigs. Piglets were weaned at 21 days of age to a corn and soybean meal-based diet supplemented with 0, 0.5, 1, 2, and 4 % MSG (n = 25/group). MSG was added to the basal diet at the expense of cornstarch. At 42 days of age (21 days after weaning), blood samples (10 mL) were obtained from the jugular vein of 25 pigs/group at 1 and 4 h after feeding for hematological and clinical chemistry tests; thereafter, pigs (n = 6/group) were euthanized to obtain tissues for histopathological examinations. Feed intake was not affected by dietary supplementation with 0–2 % MSG and was 15 % lower in pigs supplemented with 4 % MSG compared with the 0 % MSG group. Compared with the control, dietary supplementation with 1, 2 and 4 % MSG dose-dependently increased plasma concentrations of glutamate, glutamine, and other amino acids (including lysine, methionine, phenylalanine and leucine), daily weight gain, and feed efficiency in postweaning pigs. At day 7 postweaning, dietary supplementation with 1–4 % MSG also increased jejunal villus height, DNA content, and antioxidative capacity. The MSG supplementation dose-dependently reduced the incidence of diarrhea during the first week after weaning. All variables in standard hematology and clinical chemistry tests, as well as gross and microscopic structures, did not differ among the five groups of pigs. These results indicate that dietary supplementation with up to 4 % MSG is safe and improves growth performance in postweaning pigs.     

Dietary l-arginine supplementation enhances the immune status in early-weaned piglets

This study was conducted to test the hypothesis that dietary L-arginine supplementation enhances immunity in early weaned piglets. Seventy piglets weaned at 7 days of age were assigned to five groups (14 pigs/group), representing supplementation of 0.0, 0.2, 0.4, 0.6, and 0.8% L-arginine to a milk-based formula. On Day 7 after initiation of treatment, spleen weight in piglets supplemented with 0.2 and 0.8% arginine was heavier and thymus size was larger in piglets supplemented with 0.6% arginine, whereas serum concentration of immunoglobulin (Ig) M was higher but that of IL-8 was lower in piglets supplemented with 0.6 and 0.8% arginine, compared with the control group. Dietary supplementation with 0.8% arginine increased the numbers of white blood cells and granulocytes, and gene expression of interleukin (IL)-8 in spleen. On Day 14, compared with control piglets, granulocyte numbers were greater but lymphocyte numbers were lower in piglets supplemented with 0.2 and 0.4% arginine, whereas splenic expression of IL-8 and tumor necrosis factor-alpha genes was increased in piglets supplemented with 0.8% arginine. Additionally, IgG and IgM concentrations in serum and growth performance were greater in piglets supplemented with 0.4-0.8% arginine, compared with unsupplemented piglets. Collectively, dietary supplementation with 0.4-0.8% L-arginine for 2 weeks enhances both cellular and humoral immunity in piglets by modulating the production of leukocytes, cytokines and antibodies. These results indicate that increasing L-arginine provision is beneficial for optimal immune responses in young pigs and also have important implications for designing the next generation of improved formula for human infants.     

Zinc Oxide–Montmorillonite Hybrid Influences Diarrhea, Intestinal Mucosal Integrity, and Digestive Enzyme Activity in Weaned Pigs

One hundred-eighty piglets (Duroc × Landrace × Yorkshire), with an average initial weight of 7.4?kg weaned at 27?±?1?days of age, were used to evaluate the effects of dietary zinc oxide?Cmontmorillonite hybrid (ZnO?CMMT) on growth performance, diarrhea, intestinal mucosal integrity, and digestive enzyme activity. All pigs were allotted to five treatments and fed with the basal diets supplemented with 0, 250, 500, and 750?mg/kg of Zn as ZnO?CMMT or 2,000?mg/kg of Zn as ZnO. The results showed that supplementation with 500 or 750?mg/kg of Zn from ZnO?CMMT and 2,000?mg/kg of Zn from ZnO improved average daily gain, enhanced average daily feed intake, decreased fecal scores at 4, 8, and 14?days postweaning, reduced intestinal permeability which was evident from the reduced lactulose recovery and urinary lactulose/mannitol ratio, and improved the activities of protease, amylase, lipase, trypsin, and chymotrypsin both in pancreas and small intestinal contents of pigs as compared with the control. Supplemental 250?mg/kg of Zn from ZnO?CMMT also decreased fecal scores at 8 and 14?days postweaning, decreased urinary lactulose/mannitol ratio, and improved chymotrypsin activity in pancreas and small intestinal contents as well as protease activity in small intestinal contents compared with control. Moreover, the above indexes of weanling pigs fed with 500 or 750?mg/kg of Zn as ZnO?CMMT did not differ from those fed with 2,000?mg/kg of Zn as ZnO. The results demonstrated that supplementation with 500 or 750?mg/kg of Zn from ZnO?CMMT was as efficacious as 2,000?mg/kg of Zn from ZnO in improving growth performance, alleviating postweaning diarrhea, and enhancing intestinal mucosal integrity and the digestive enzyme activities in pancreas and small intestinal contents of pigs. The results that feeding lower concentrations of ZnO?CMMT to weanling pigs maintained performance will be beneficial for the environment and for sustaining swine production.     

Supplementation with branched-chain amino acids to a low-protein diet regulates intestinal expression of amino acid and peptide transporters in weanling pigs

This study determined the effects of dietary branched-chain amino acids (AA) (BCAA) on growth performance, expression of jejunal AA and peptide transporters, and the colonic microflora of weanling piglets fed a low-protein (LP) diet. One hundred and eight Large White × Landrace × Duroc piglets (weaned at 28 days of age) were fed a normal protein diet (NP, 20.9 % crude protein), an LP diet (LP, 17.1 % crude protein), or an LP diet supplemented with BCAA (LP + BCAA, 17.9 % crude protein) for 14 days. Dietary protein restriction reduced piglet growth performance and small-intestinal villous height, which were restored by BCAA supplementation to the LP diet to values for the NP diet. Serum concentrations of BCAA were reduced in piglets fed the LP diet while those in piglets fed the LP + BCAA diet were similar to values for the NP group. mRNA levels for Na⁺-neutral AA exchanger-2, cationic AA transporter-1, b^0,+ AA transporter, and 4F2 heavy chain were more abundant in piglets fed the LP + BCAA diet than the LP diet. However, mRNA and protein levels for peptide transporter-1 were lower in piglets fed the LP + BCAA diet as compared to the LP diet. The colonic microflora did not differ among the three groups of pigs. In conclusion, growth performance, intestinal development, and intestinal expression of AA transporters in weanling piglets are enhanced by BCAA supplementation to LP diets. Our findings provide a new molecular basis for further understanding of BCAA as functional AA in animal nutrition.     

人三叶因子3在毕赤酵母中表达条件的研究

为提高人三叶因子 3 (HumanTrefoilfactor 3 ,hTFF3 )在毕赤酵母中的表达量 ,研究了转化子生长的培养条件 ,包括不同碳源对转化子生长的影响和接种量、甲醇浓度、pH值、摇瓶转速及不同诱导时间对人三叶因子 3表达的影响。结果表明转化子在生长阶段加入葡萄糖生长旺盛 ,培养 14h后OD₆₀₀ 就可达到 50。在 100mL生长培养基上的菌液以 1∶1接入诱导培养基时蛋白表达量最高 ;转化子在 1%的甲醇、pH60、摇瓶转速240r/min的条件下诱导4 8h ,菌体密度OD₆₀₀为 15 ,目的蛋白表达量达到 20mg L。用 5L发酵罐进行了高密度发酵 ,经2%甲醇32h诱导 ,最终菌体密度OD₆₀₀ 达到 120 ,每升发酵液中含目的蛋白100mg。     

Effects of Dietary Supplementation with Glutamate and Aspartate on Diquat-Induced Oxidative Stress in Piglets

This study aimed to investigate the protective effects of dietary glutamate and aspartate supplementations on diquat-induced oxidative stress in piglets. Diquat injection significantly reduced growth performance, including body weight, average daily weight gain, and feed intake (P<0.05). Meanwhile, diquat administration induced oxidative stress evidenced by the decreased serum nitric oxide (NO) and elevated malondialdeyhde (MDA) concentration (P<0.05). Furthermore, diquat-induced oxidative stress disrupted intestinal absorption system and decreased serum threonine, serine, and glycine levels. Dietary supplementation with glutamate improved final body weight, antioxidant system, and expressions of amino acids transporters and enhanced serum glutamate concentration compared with diquat group (P<0.05). While aspartate failed to alleviate diquat-induced oxidative stress, growth depression, and dysfunction of nutrients absorption except for liver relative weight. In conclusion, dietary supplementation with glutamate confers beneficial effects on diquat-induced oxidative stress in piglets, while aspartate exhibits little effects.     

人纤溶蛋白酶原K5在毕赤酵母中的表达及其生物活性鉴定

化学合成人纤溶蛋白酶原K5 (pK5 )的编码基因并克隆到毕赤氏酵母表达系统的分泌型载体pPIC9K上 ,将重组质粒经BglⅡ单酶切后电转化PichiapastorisGS115菌株 ,筛选出对G4 18有高抗性和在MM培养基上生长缓慢的转化子。经摇瓶发酵和甲醇诱导后 ,用 15 %SDS PAGE检测发酵上清液 ,表明有重组蛋白pK5的高表达。经CM-Sepherose离子交换柱和Superdex 75分子筛层析两步分离纯化 ,获得了纯度达到 98%的rpK5。用MTT方法检测的结果表明 ,纯化的rpK5可显著地抑制人血管内皮细胞的生长     

Effects of orally administered probiotic Pediococcus acidilactici on the small and large intestine of weaning piglets. A qualitative and quantitative micro-anatomical study

Probiotic research has been approached, above all in recent years, by widely differing points of view, both for human and animal uses. Lactic acid bacteria release bacteriocins, and some of them may function as probiotic. The aim of the present study was to investigate the effects of dietary supplementation with the probiotic Pediococcus acidilactici on the piglet intestine, on circulating lymphocytes, and on aspects of piglet performance during the first 42 days after weaning. Sixteen female piglets were at weaning assigned to two dietary groups: Control (Ctr, 8 animals) and Pediococcus acidilactici supplemented (Pa, 8 animals). Piglets' growth was monitored from weaning to the end of the trial. On day 42 post-weaning, the piglets were slaughtered and small specimens from both ileum and cecum were examined with haematoxylin/eosin staining to ascertain structural details. Histometry was performed by villi and crypts measurements, as well as GALT measurements. Histochemical analyses were performed to investigate the intestinal mucins. Immunohistochemical analyses were used to visualize proliferating as well as apoptotic mucosal cells, and to identify mucosal macrophages and IgA producing cells. Intra-epithelial CD8+ T lymphocytes were identified and counted. Subsets of circulating T lymphocytes were analyzed by flow cytometry. Pediococcus acidilactici supplementation positively influenced weight and post-weaning average daily gain of treated piglets. Histometry showed an increase in villi height and crypts depth in Pa animals in comparison with controls. Treated piglets showed a larger number of proliferating enterocytes than controls. Intra-epithelial CD8+ T lymphocytes were scarcer in treated than in control piglets, likely in relation with catarrhal enteritis shown in the latter. We conclude that the studied supplementation was possibly able to protect the piglet small intestinal mucosa, improving local resistance to infections in the stressful weaning period.     

Effects of dietary nucleotide supplementation on growth performance and hormonal and immune responses of piglets

The effects of dietary nucleotide supplementation from 9 days of age until the end of post-weaning on piglets hormonal and immune responses and on growth performance were investigated. During lactation (days 9 to 21) and post-weaning (days 22 to 55) 10 [HBI Fomeva11 × (Large White × Landrace)] litters (n = 108 piglets) had ad libitum access to two standard diets, both supplemented with 0% (T0 group) or 0.1% (T1 group) of yeast extract nucleotides. BW of piglets at days 21 (P < 0.10), 35 and 55 (P < 0.05) was greater in T1 compared with T0. Feed intake was not different between groups (P > 0.05). Cortisol content was lower in T1 than in T0 at days 28 and 35 (P < 0.05), whereas growth hormone was lower at day 35 (P < 0.05). Levels of IGF-1 were similar across groups (P > 0.05). Nucleotide-supplemented diets increased lymphocyte subpopulation CD4-CD8+high at days 21 and 35 (P < 0.05), whereas CD4+CD8- cells were higher in T1 than in T0 at day 21 (P < 0.05). Peripheral blood mononuclear cells cytokine expression was influenced by dietary nucleotide supplementation. At weaning, interleukin (IL)-6 and IL-1β expression was lower (P < 0.05) in T1 compared with T0, whereas the expression of interferon (IFN)-γ and IL-10 was higher (P < 0.05). At day 28, piglets in T1 showed higher values of tumor necrosis factor (TNF)-α expression than T0 and lower values of IL-10 expression (P < 0.05). Dietary nucleotide supplementation had a suppressive effect on IL-6 and IL-10 expression (P < 0.05) at day 35. On the contrary, the expression of IFN-γ, TNF-α and IL-1β was enhanced (P < 0.05). In conclusion, these results suggest that starting a dietary nucleotide supplementation before weaning can improve the adaptive capabilities of weaned piglets to the stressors, enhancing the growth performance.     

Dietary supplementation with l-arginine partially counteracts serum metabonome induced by weaning stress in piglets

Arginine plays an important role in preventing intestinal dysfunction and metabolic disorders caused by early weaning stress. However, little is known about how arginine mitigates early weaning stress. This study was conducted to evaluate the effects of weaning stress and dietary arginine supplementation on the metabonome in the serum of piglets using (1)H NMR spectroscopy in conjunction with multivariate data analysis. Thirty castrated male piglets aged 21 d were evenly divided into three groups and fed in three different regimes: sow-fed (SF), weaned with l-alanine supplementation (ALA), and weaned with arginine supplementation (ARG). We found that early weaning stress led to a significantly reduced bodyweight gain (15.6%) and that supplementation with arginine can improve growth rates in piglets by 5.6% (P < 0.05). The early weaning stress was associated with marked alterations in lipid and amino acid metabolisms and perturbations in population and/or activities of gut microorganisms, which were manifested in increased levels of organic acids, amino acids, and acetyl-glycoproteins and reduced levels of choline metabolism and lipoproteins. Dietary supplementation with arginine could partially counteract the changes of metabolites induced by weaning stress, such as lipid and amino acid metabolisms. However, arginine was not able to restore disturbed gut microbiota. These results demonstrate the central role of arginine supplementation in regulating the metabolisms of weaned piglets.     

Impact of the probiotic bacteria Enterococcus faecium NCIMB 10415 (SF68) and Bacillus cereus var. toyoi NCIMB 40112 on the development of serum IgG and faecal IgA of sows and their piglets

To examine the influence of two different probiotic bacteria on the humoral immune system of swine, two animal studies were carried out with sows and their litters. The sows' feed was supplemented with either Enterococcusfaecium NCIMB 10415 (SF68) or Bacillus cereus var. toyoi NCIMB 40112 beginning early in pregnancy. The total IgA content in the faeces as well as the total IgG concentration in the blood of the sows was recorded before and after weaning. The same parameters were determined in the blood and faeces of the piglets. In sows, only feed supplementation with B. cereus led to a clear increase in faecal IgA. Serum IgG levels were not significantly affected by any probiotic feeding in sows. In piglets, the group that was fed B. cereus showed significantly higher faecal IgA levels shortly before weaning, whereas in the E. faecium group, a significant decrease in IgA levels was observed one week after weaning. In both probiotic fed groups the post-weaning IgG levels were significantly decreased compared to the respective control groups. We conclude that B. cereus var. toyoi feed supplementation led to an increased intestinal IgA secretion both in sows and piglets. This effect could be related to a more successful mucosal defence which in turn led to a lower level in systemic IgG production in piglets after weaning.     

Molecular genetic manipulation of Pichia pastoris SEC4 governs cell growth and glucoamylase secretion

We have previously engineered a recombinant Pichia pastoris GS115 transformant, MSPGA-7, harboring seven copies of glucoamylase (GA) fused with modified signal peptide. High yield secretion of GA was achieved as an extra copy of SEC4 was integrated to the transformant. To elucidate the physiological role of SEC4, a dominant-negative mutant of SEC4, SEC4(S28N), was overexpressed under the control of alchohol oxidase 1 (AOX1) promoter in P. pastoris strain MSPGA-7 as well as a set of host cells harboring multi-copy of wild type SEC4. We found that SEC4(S28N) mutation in the key guanine nucleotide binding domain reduced guanine nucleotide binding affinity, hence it blocked the transport of vesicles required for targeting and fusion to the plasma membrane. The inhibitory levels of cell growth and GA secretion were correlated with the dosage of SEC4(S28N) gene. In addition, overexpression of SEC4 driven by AOX1 promoter in MSPGA-7 improved the secretory production of GA, but demonstrated the delay of cell growth by increased gene dosage of SEC4. Interestingly, a limited level of Sec4p did not disturb the cell growth. It was because expression of only one copy of SEC4 resulted in delay of cell growth at an early stage while still maintaining high level Sec4p at long-term incubation. Accordingly, as glyceraldehyde-3-phosphate dehydrogenase promoter was used to substitute AOX1 promoter to drive the SEC4 expression, enhanced GA secretion but not inhibition of cell growth was achieved. Taken together, our results demonstrate that SEC4 is essential for P. pastoris in regulating cell growth and heterologous protein secretion in a dosage-dependent manner.     

Dietary Sodium Butyrate Supplementation Promotes Oxidative Fiber Formation in Mice

Sodium butyrate (SB), a sodium salt of butyric acid, has been shown to improve the animal production performance. The aim of this work was to test the effect of feeding mice with diets containing different dose of SB (1, 3, and 5%) on oxidative fiber formation. Dietary SB supplementation had no effect on body weights and food intakes. Dietary SB supplementation upregulated the expressions of oxidative fiber-related protein including MyHC I, MyHC IIa, myoglobin, and troponin-I-slow. Dietary SB supplementation also upregulated the expressions of phospho-FoxO1 and MEF2C protein, but did not affect total FoxO1 protein expression. Taken together, these results indicate that dietary SB supplementation promotes oxidative fiber formation in mice, which might be through inactivation of FoxO1 and upregulation of MEF2C expression.