Rhein kills Actinobacillus pleuropneumoniae, reduces biofilm formation, and effectively treats bacterial lung infections in mice.

Background. Actinobacillus pleuropneumoniae, a member of the Pasteurellaceae family, is known for its highly infectious nature and is the primary causative agent of infectious pleuropneumonia in pigs. This disease poses a considerable threat to the global pig industry and leads to substantial economic losses due to reduced productivity, increased mortality rates, and the need for extensive veterinary care and treatment. Due to the emergence of multi-drug-resistant strains, Chinese herbal medicine is considered one of the best alternatives to antibiotics due to its unique mechanism of action and other properties. As a type of Chinese herbal medicine, Rhein has the advantages of a wide antibacterial spectrum and is less likely to develop drug resistance, which can perfectly solve the limitations of current antibacterial treatments.Methods. The killing effect of Rhein on A. pleuropneumoniae was detected by fluorescence quantification of differential expression changes of key genes, and scanning electron microscopy was used to observe the changes in A. pleuropneumoniae status after Rhein treatment. Establishing a mouse model to observe the treatment of Rhein after A. pleuropneumoniae infection.Results. Here, in this study, we found that Rhein had a good killing effect on A. pleuropneumoniae and that the MIC was 25 µg ml-1. After 3 h of action, Rhein (4×MIC) completely kills A. pleuropneumoniae and Rhein has good stability. In addition, the treatment with Rhein (1×MIC) significantly reduced the formation of bacterial biofilms. Therapeutic evaluation in a murine model showed that Rhein protects mice from A. pleuropneumoniae and relieves lung inflammation. Quantitative RT-PCR (Quantitative reverse transcription polymerase chain reaction is a molecular biology technique that combines both reverse transcription and polymerase chain reaction methods to quantitatively detect the amount of a specific RNA molecule) results showed that Rhein treatment significantly downregulated the expression of the IL-18 (Interleukin refers to a class of cytokines produced by white blood cells), TNF-α, p65 and p38 genes. Along with the downregulation of genes such as IL-18, it means that Rhein has an inhibitory effect on the expression of these genes, thereby reducing the activation of inflammatory cells and the production of inflammatory mediators. This helps reduce inflammation and protects tissue from further damage.Conclusions. This study reports the activity of Rhein against A. pleuropneumoniae and its mechanism, and reveals the ability of Rhein to treat A. pleuropneumoniae infection in mice, laying the foundation for the development of new drugs for bacterial infections.

Effect of Gan Cao (Glycyrrhiza uralensis Fisch) polysaccharide on growth performance, immune function, and gut microflora of broiler chickens.

Glycyrrhiza uralensis Fisch, also called Gan Cao, is a commonly prescribed herb in traditional Chinese medicine. Gan Cao is associated with immune-modulation and antitumor potential though its mechanism of action is not well-known. To explore the effects of different dietary levels of Gan Cao polysaccharide (GCP) on broilers, a total of 400 Avian broiler chickens were randomly divided into 4 groups with 10 replicates of 10 broilers each. The broilers in the control group were fed a basal diet, while those in the experimental groups were fed the basal diet supplemented with 0.5%, 1.0%, and 1.5% GCP, respectively, for 42 d. The results showed a significant increase in the growth performance in the GCP groups. The antibody titer of NDV and the phagocytosis index was higher in the birds with GCP treatment than in the control group, with the 1% GCP addition displaying the highest titer. The Lactobacillus and Bifidobacteria count in the cecum content of the birds in the 1% GCP group was higher compared to the other groups. In conclusion, dietary supplementation with GCP had a substantial impact on the growth performance, immune response, and microflora population in the cecum of the birds, especially at a level of 1% addition.

Involvement of eIF2α in halofuginone-driven inhibition of TGF-ß1-induced EMT.

Halofuginone (HF) is an extract from the widely used traditional Chinese medicine (TCM) Dichroa febrifuga that facilitates the recovery of wounds and attenuates hepatic fibrosis. However, the role of HF in the epithelial-mesenchymal transition (EMT) of IPEC-J2 cells remains unclear. The current study explored the anti-EMT effect of HF in IPEC-J2 cells and illustrates its molecular mechanism. Transforming growth factor ß1 (TGF-ß1), as a recognized profibrogenic cytokine, decreased the level of the epithelial marker E-cadherin and increased the level of the mesenchymal markers, such as N-cadherin, fibronectin (FN), vimentin (Vim), and α-smooth muscle actin (α-SMA), in IPEC-J2 cells depending on the exposure time and dose. HF markedly prevented the EMT induced by TGF-ß1. Dissection of the mechanism revealed that HF inhibited IPEC-J2 cell EMT via modulating the phosphorylation of SMAD2/3 and the SMAD2/3-SMAD4 complex nuclear translocation. Furthermore, HF could promote the phosphorylation of eukaryotic translation initiation factor-2α (eIF2α), which modulates the SMAD signaling pathway. These results suggested that HF inhibits TGF-ß1-induced EMT in IPEC-J2 cells through the eIF2α/SMAD signaling pathway. Our findings suggest that HF can serve as a potential anti-EMT agent in intestinal fibrosis therapy.

miR-31 shuttled by halofuginone-induced exosomes suppresses MFC-7 cell proliferation by modulating the HDAC2/cell cycle signaling axis.

Traditional Chinese medicine (TCM) are both historically important therapeutic agents and important source of new drugs. Halofuginone (HF), a small molecule alkaloid derived from febrifugine, has been shown to exert strong antiproliferative effects that differ markedly among various cell lines. However, whether HF inhibits MCF-7 cell growth in vitro and underlying mechanisms of this process are not yet clear. Here, we offer the strong evidence of the connection between HF treatment, exosome production and proliferation of MCF-7 cells. Our results showed that HF inhibits MCF-7 cell growth in both time- and dose-dependent manner. Further microRNA (miRNA) profiles analysis in HF treated and nontreated MCF-7 cell and exosomes observed that six miRNAs are particularly abundant and sorted in exosomes. miRNAs knockdown experiment in exosomes and the MCF-7 growth inhibition assay showed that exosomal microRNA-31 (miR-31) modulates MCF-7 cells growth by specially targeting the histone deacetylase 2 (HDAC2), which increases the levels of cyclin-dependent kinases 2 (CDK2) and cyclin D1 and suppresses the expression of p21. In conclusion, these data indicate that inhibition of exosome production reduces exosomal miR-31, which targets the HDAC2 and further regulates the level of cell cycle regulatory proteins, contributing to the anticancer functions of HF. Our data suggest a new role for HF and the exosome production in tumorigenesis and may provide novel insights into prevention and treatment of breast cancer.

Evaluation of sample extracting methods of FCSM by Lactobacillus acidophilus based on a UPLC-Q-TOF-MS global metabolomics analysis

Abstract The study of metabolomics requires extracting as many metabolites as possible from a biological sample. This study aimed to determine the optimal method for the extraction of metabolites from solid-state fermented cottonseed meal (FCSM). The UPLC-Q-TOF-MS global metabolomics technology was used to detect the metabolites in FCSM, and the extraction quantity and extraction efficiency of seven different extraction methods, specifically the WA, 50MeOH, 50MeOHB, 50MeCNB, 80MeOHB, 80MeOH and AMF methods were evaluated. The results showed that the number of VIP metabolites extracted by AMF method are 196 and 184 in ESI+ and ESI- mode respectively, it is the largest number of all exacted methods; and the AMF methods also provided a higher extraction efficiency compared with the other methods, especially in indoleacrylic acid, dl-tryptophan and epicatechin (p < 0.01). As a result, AMF/-4 °C method was identified as the best method for the extraction of metabolites from FCSM by Lactobacillus acidophilus. Our study establishes a technical basis for future metabolomics research of fermented feed.

Halofuginone-induced autophagy suppresses the migration and invasion of MCF-7 cells via regulation of STMN1 and p53.

Traditional Chinese medicines have been recognized as especially promising anticancer agents in modern anticancer research. Halofuginone (HF), an analog of quinazolinone alkaloid extracted from Dichroa febrifuga, is widely used in traditional medicine. However, whether HF inhibits the growth of breast cancer cells and/or reduces the migration and invasion of MCF-7 human breast cancer cells, as well as the underlying mechanisms in vitro, remains unclear. In this study, we report that an HF extract inhibits the growth of MCF-7 cells and reduces their migration and invasion, an important feature of potential anticancer agents. In addition, HF significantly increases the activation of autophagy, which is closely associated with tumor metastasis. As STMN1 and p53 have been closely implicated in breast cancer progression, we analyzed their expression in the context of HF extract treatment. Western blot analysis showed that HF suppresses STMN1 and p53 expression and activity in an autophagy-dependent manner. Collectively, these data indicate that activation of autophagy reduces expression of STMN1 and p53, and the migration and invasion of cancer cells contributes to the anti-cancer effects of the HF. These findings may provide new insight into breast cancer prevention and therapy.

Evaluation of sample extracting methods of FCSM by Lactobacillus acidophilus based on a UPLC-Q-TOF-MS global metabolomics analysis.

The study of metabolomics requires extracting as many metabolites as possible from a biological sample. This study aimed to determine the optimal method for the extraction of metabolites from solid-state fermented cottonseed meal (FCSM). The UPLC-Q-TOF-MS global metabolomics technology was used to detect the metabolites in FCSM, and the extraction quantity and extraction efficiency of seven different extraction methods, specifically the WA, 50MeOH, 50MeOHB, 50MeCNB, 80MeOHB, 80MeOH and AMF methods were evaluated. The results showed that the number of VIP metabolites extracted by AMF method are 196 and 184 in ESI+ and ESI- mode respectively, it is the largest number of all exacted methods; and the AMF methods also provided a higher extraction efficiency compared with the other methods, especially in indoleacrylic acid, dl-tryptophan and epicatechin (p<0.01). As a result, AMF/-4°C method was identified as the best method for the extraction of metabolites from FCSM by Lactobacillus acidophilus. Our study establishes a technical basis for future metabolomics research of fermented feed.

Potential of novel antimicrobial peptide P3 from bovine erythrocytes and its analogs to disrupt bacterial membranes in vitro and display activity against drug-resistant bacteria in a mouse model.

With the emergence of many antibiotic-resistant strains worldwide, antimicrobial peptides (AMPs) are being evaluated as promising alternatives to conventional antibiotics. P3, a novel hemoglobin peptide derived from bovine erythrocytes, exhibited modest antimicrobial activity in vitro. We evaluated the antimicrobial activities of P3 and an analog, JH-3, both in vitro and in vivo. The MICs of P3 and JH-3 ranged from 3.125 µg/ml to 50 µg/ml when a wide spectrum of bacteria was tested, including multidrug-resistant strains. P3 killed bacteria within 30 min by disrupting the bacterial cytoplasmic membrane and disturbing the intracellular calcium balance. Circular dichroism (CD) spectrometry showed that P3 assumed an α-helical conformation in bacterial lipid membranes, which was indispensable for antimicrobial activity. Importantly, the 50% lethal dose (LD50) of JH-3 was 180 mg/kg of mouse body weight after intraperitoneal (i.p.) injection, and no death was observed at any dose up to 240 mg/kg body weight following subcutaneous (s.c.) injection. Furthermore, JH-3 significantly decreased the bacterial count and rescued infected mice in a model of mouse bacteremia. In conclusion, P3 and an analog exhibited potent antimicrobial activities and relatively low toxicities in a mouse model, indicating that they may be useful for treating infections caused by drug-resistant bacteria.

Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells.

Severe acute respiratory syndrome coronavirus (SARS-CoV) is the pathogen of SARS, which caused a global panic in 2003. We describe here the screening of Chinese herbal medicine-based, novel small molecules that bind avidly with the surface spike protein of SARS-CoV and thus can interfere with the entry of the virus to its host cells. We achieved this by using a two-step screening method consisting of frontal affinity chromatography-mass spectrometry coupled with a viral infection assay based on a human immunodeficiency virus (HIV)-luc/SARS pseudotyped virus. Two small molecules, tetra-O-galloyl-beta-D-glucose (TGG) and luteolin, were identified, whose anti-SARS-CoV activities were confirmed by using a wild-type SARS-CoV infection system. TGG exhibits prominent anti-SARS-CoV activity with a 50% effective concentration of 4.5 microM and a selective index of 240.0. The two-step screening method described here yielded several small molecules that can be used for developing new classes of anti-SARS-CoV drugs and is potentially useful for the high-throughput screening of drugs inhibiting the entry of HIV, hepatitis C virus, and other insidious viruses into their host cells.