Expression of chicken epidermal growth factor (cEGF) in Escherichia coli regulates the microflora structure of the duodenum to improve growth performance and intestinal morphogenesis in broilers.

1. A study used gene synthesis to obtain the functional domains of chicken epidermal growth factor (cEGF) and examined their impact on broiler growth performance, small intestinal morphology, digestive enzyme activities in the intestinal contents and the structure of duodenal microflora.2. The pET-32a-cEGF recombinant expression vector was constructed. The specific band at 26 KDa was shown by SDS-PAGE analysis and WB results. The purified protein content was shown to be 1687 µg/ml by assay.3. A total of 180 healthy, one-day-old Arbor Acres male, white-feathered broilers were randomly divided into three dietary treatment groups (six replicate pens, 10 birds per replicate): A control diet (ND); cEGF diet (cEGF), control supplemented with 250 mg/kg cEGF and the control diet (CD) supplemented with 250 mg/kg chlortetracycline.4. The results showed that feeding the cEGF and CD diet reduced FCR of broilers aged 1-21 d, average daily feed intake (ADFI) at 22-42 d, and the FCR in the whole period (1-42 d; p < 0.05). Compared with the ND group, the cEGF diet increased duodenal α-amylase and alkaline phosphatase activities in the 1-21 d, duodenal lipase, alkaline phosphatase, and ileal alkaline phosphatase activities in the post-period and increased villus height in the duodenum and ileum (p < 0.05). In addition, the ACE and Chao1 index for the birds fed cEGF were higher than the ND group (p < 0.05). At the phyla level, Firmicutes and Proteobacteria were dominant in all groups. At the genus level, the dominant genus was Lactobacillus. The LEfSe analysis showed that the cEGF group was enriched by 11 species including Brevibacillus, Eisenbergiella, Cloacibacterium, Butyricoccus spp.5. The addition of 250 mg/kg cEGF to the diet can increase growth performance by improving intestinal development and digestive enzyme activity, which may be related to the duodenal intestinal microflora. Therefore, cEGF is an effective alternative to antibiotics in broiler farming.

Stearidonic acid-enriched flax oil reduces the growth of human breast cancer in vitro and in vivo.

The 20 and 22 carbon n-3 long-chain polyunsaturated fatty acids (LCPUFA) inhibit the growth of tumors in vitro and in animal models, but less is known about the 18 carbon n-3, stearidonic acid (SDA). This study aimed to establish and determine a mechanism for the anti-cancer activity of SDA-enriched oil (SO). SO (26 % of lipid) was produced by genetically engineering flax and used to treat human tumorigenic (MDA-MB-231, MCF-7) and non-tumorigenic (MCF-12A) breast cells. Nu/nu mice bearing MDA-MB-231 tumor were fed SO (SDA, 4 % of fat). Cell/tumor growth, phospholipid (PL) composition, apoptosis, CD95, and pro-apoptotic molecules were determined in SO-treated cells/tumors. Compared to a control lipid mixture, SO reduced (p < 0.05) the number of tumorigenic, but not MCF-12A cells, and resulted in higher concentration of most of the n-3 fatty acids in PL of all cells (p < 0.05). However, docosapentaenoic acid increased only in tumorigenic cells (p < 0.05). SO diet decreased tumor growth and resulted in more n-3 LCPUFA, including DPA and less arachidonic acid (AA) levels in major tumor PL (p < 0.05). Treatment of MDA-MB-231 cells/tumors with SO resulted in more apoptotic cells (in tumors) and in vivo and in vitro, more CD95+ positive cells and a higher expression of apoptotic molecules caspase-10, Bad, or Bid (p < 0.05). Supplementing SO alters total PL and PL classes by increasing membrane content of n-3 LCPUFA and lowering AA (in vivo), which is associated with increased CD95-mediated apoptosis, thereby suggesting a possible mechanism for reduce tumor survival.

Effect of Ginkgo biloba extract on matrix metalloproteinase-3 expression in a rat model of chondrocyte injury.

A rat model with cartilage chondrocyte injury was established using interleukin-1ß (IL-1ß) to investigate the effect of Ginkgo biloba extract (EGb) on matrix metalloproteinase-3 (MMP-3) expression. Rat chondrocytes were extracted and randomly divided into six groups: control group, IL-1ß (model) group, IL-1ß + dexamethasone group, and IL-1ß + EGb group (both high and low dose groups). Reverse transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay were used to detect MMP-3 expression. Compared to the MMP-3 mRNA level in the control group, MMP-3 mRNA level significantly increased in the model group (P < 0.05). The application of dexamethasone or EGb significantly decreased the MMP-3 mRNA level (P < 0.05). MMP-3 mRNA and protein levels decreased in the EGb-treated group, especially in the high-dose group, compared to those in the dexamethasone group (P < 0.05). EGb may reduce MMP-3 production during IL-1ß-induced chondrocyte damage and protect chondrocytes to some extent, with better efficacy at high doses.

The correlation between skin electrical conductance and the score of qi vacuity.

In traditional Chinese medicine, the syndrome of qi vacuity means that the patient's body has a low level of energy to react to stress. Recently, we used a score, the QV score, by scaling the severity of symptoms and signs of qi vacuity in patients with tiredness. The aim of this study was to investigate the relationship between QV score and skin electrical conductance in patients with tiredness. One hundred and forty-three healthy controls and 103 patients with tiredness were involved. Each subject received a weak electrical stimulation with constant voltage (1.75 volt), and conductance was measured between two different limbs. The mean value of skin conductance among four limbs was calculated and expressed by a special unit, namely Chin. The correlation between the skin conductance and QV score was analyzed by a linear regression analysis. The results showed that skin electrical conductance of healthy controls was negatively correlated with age (r-coefficient = -0.51, P = 0.000). The skin conductance of patients with tiredness was significantly lower than that of healthy controls with matching age (P = 0.000 by Student's t-test). Moreover, there was a positive correlation between the decrease of skin conductance and the QV score in patients with tiredness (r-coefficient = +0.68, P = 0.000). These results suggest that a decrease in skin electrical conductance may be closely related to the severity of qi vacuity. The skin conductance test is a simple, reliable, and quantitative method for detection of syndrome of qi vacuity.

[3H]ouabain binding to cultured endothelial cells: effect of cholesterol enrichment.

Binding experiments were performed with [3H]ouabain on cultured human umbilical vein endothelial cells (huvEC). Saturation studies yielded a binding capacity (Bmax) of 820 +/- 81 fmole/mg pr.(n = 4) and dissociation constant (KD) of 11.7 +/- 2.1nM (n = 4) in K(+)-free buffer for specific [3H] ouabain binding on these cells. External K+ inhibited this binding in a dose-dependent manner. The mean value of Bmax is equivalent to about 4 x 10(5) sites per cell, comparable with that of smooth muscle cell. These data demonstrated the presence of specific [3H]ouabain binding linked to Na+/K+ pump, consistent with the observations of ouabain-sensitive 86Rb uptake in huvEC. Effect of cholesterol enrichment was also studied. Incubation in media supplemented with cholesterol-phospholipid liposomes of molar ratio of 2:1 for 18 hours reduced the Bmax by 31% (P < 0.05) without significantly changed the value of KD. This reduction of [3H]ouabain binding appeared to be specific for cholesterol since liposome made with pure phospholipid did not alter binding. Recent findings indicate that cholesterol-enrichment and plasma lipoproteins enhance vascular contractile response, our results suggest that the cholesterol-enrichment of endothelial cells may also indirectly affect the vascular response via disturbing the function of Na+/K+ pump.

Lipid composition of Chlamydia psittaci grown in monkey kidney cells in defined medium.

The lipid compositions of (i) monkey kidney (MK-2) cells cultivated in Eagle's minimal essential medium (MEM) with 5% calf serum, (ii) MK-2 cells cultivated in Waymouth medium supplemented with 20 mug of sodium oleate and 2 mg of bovine albumin per ml, (iii) Chlamydia psittaci strain 6BC grown in the latter host system, and (iv) calf serum were compared. Strain 6BC contains 31% phosphatidyl ethanolamine (PE) and 15% phosphatidyl glycerol (PG), whereas the host cell contains almost the same amount of PE (27%) and no PG. A high concentration of total lipid was observed in strain 6BC (29 to 34%), whereas MK-2 cells contain only 9 to 15% and calf serum contains 4.5% total lipid. The fatty acids of the total lipid from strain 6BC contain branched-chain acids. These fatty acids were found mostly in PE (33.0%) and PG (37.0%). No branched-chain fatty acid was found in the MK-2 cells. There was an increase in triglyceride content when MK-2 cells cultivated in MEM (19.2%) were compared with cells cultivated in Waymouth medium (28.0%). A high concentration (62.0%) of octadecenoic acid (C18:1) was found in the triglyceride of MK-2 cells cultivated in Waymouth medium. The level of polyunsaturated fatty acids observed in MK-2 cells cultivated in Waymouth medium (10.8%) and in the chlamydiae grown in these cells (13.3%) was low compared with the level in MK-2 cells (28.8%) cultivated in MEM with 5% calf serum and the level in calf serum itself (50.8%). A higher ratio of sterol ester to free sterol was found in calf serum than in MK-2 cells or in chlamydiae. Host contribution to lipid composition of strain 6BC is discussed.