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This research demonstrated the protective effect and possible mechanism of the Sophora viciifolia extract (SVE) against acetaminophen-induced liver injury in mice. The levels of ALT and AST in the serum and antioxidant enzyme activity in the liver were measured. We used immunohistochemistry to detect CYP2E1, Nrf2, and Keap1 protein expression in the liver. The mRNA expression in the liver of TNF-α, NF-κB, and IL-6, Nrf2 and its downstream genes HO-1 and GCLC were measured by qRT-PCR. We found that SVE could decrease the ALT and AST levels, promote the activities of SOD, CAT, GSH-Px, and GSH, and ameliorate pathological liver lesions. SVE could down-regulate the mRNA expression of inflammatory factors and up-regulate Nrf2, HO-1 and GCLC. SVE reduced the protein expression of the CYP2E1 and increased the Nrf2 and Keap1. SVE has been shown to have a protective effect against APAP-induced liver injury, possibly through activation of the Keap1-Nrf2 pathway., Competing Interests: The authors report no conflicts of interest in this work.

This study investigated the protective effect of Sophora davidi (Franch.) Skeels fruits extract (SDE) on d-galactose-induced acute aging in mice. Ultra performance liquid chromatography coupled with tine-of-flight mass spectrometry (UPLC-Q-TOF/MS) was performed to identify the composition of compounds in SDE. KM mice were divided stochastically into the normal control group (NC, saline), d-galactose (D-gal) model group, vitamin C (Vc) group (positive control), low-, medium-and high-dose SDE treat groups. After 28 days administration and fasting overnight, the serum, liver, and brain samples of mice were collected. The levels of inducible nitric oxide synthase (iNOS), acetylcholinesterase (AChE) activity in the brain, malondialdehyde (MDA) and reduced glutathione (GSH) content, superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) activity in the liver and brain were measured. Immunohistochemistry was applied to detect silent information regulator 1 (SIRT1) and p53 protein expression in the liver and brain, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of nuclear factor κB (NF-κB), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and anti-aging factor Klotho in the liver and brain. The results showed that UPLC-Q-TOF/MS identified 78 compounds in SDE. SDE could reduce the iNOS activity in serum and AChE activity in the brain, upregulate the levels of SOD, T-AOC and GSH in liver and brain, and debase the MDA content in liver and brain. SDE could downregulate the mRNA expressions of TNF-α, NF-kB, IL-1β, and IL-6 in the liver and brain, and elevate the mRNA expression of Klotho. SDE improved the pathological changes of the liver and brain induced by D-gal, increased the expression of SIRT1 protein in the liver and brain, and inhibited the expression of p53 protein induced by D-gal. To summarize, SDE demonstrated clear anti-aging effect, and its mechanism may be relevant to the activation of the SIRT1/p53 signal pathway., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lin, Xu, Wu, Qi, Xu, Liu, Zhang and Chen.)

Background: Vibrio are the main pathogenic bacteria in aquaculture. The flagellin protein C (FlaC) of Vibrio alginolyticus has good immunogenicity and the prospect of potential application in a vaccine., Objectives: We aimed to evaluate the immunogenicity, protective immunity, and prokaryotic expression fermentation of V. alginolyticus FlaC protein for the vaccine in aquaculture., Material and Methods: A molecular cloning method was used to construct the expression strain of FlaC protein, and the protein was purified with Ni-affinity chromatography. Polyclonal antiserum was prepared via mice immunized with the FlaC protein. The Western blot and enzyme-linked immunosorbent assay (ELISA) were used to check the specificity and titre of the antiserum. ELISA and pull-down assay detected the interaction between FlaC protein antiserum and Vibrio . The immune protection function of FlaC protein was detected with mice actively immunized with FlaC protein and challenged by V. alginolyticus and V. parahaemolyticus . The optimal expression conditions for FlaC protein were detected using an L 9 (3 4 ) orthogonal design model., Results: The expression strain of FlaC protein was obtained successfully, and purified FlaC protein was prepared using a mice polyclonal antibody. The FlaC protein antiserum held a high specificity, and the titre was 13200. The antiserum directly interacted with V. alginolyticus and V. parahaemolyticus , and the FlaC protein demonstrated a significant immune protection function (50%) against V. alginolyticus infection and some immune protection function (41.66%) against V. parahaemolyticus . The optimal expression conditions for FlaC protein included a strain OD 600 value of 0.8, final isopropyl-β-d-thiogalactoside (IPTG) concentration of 0.1 mmol/L, an inducing time of 8 hours, and an inducing temperature of 28°C., Conclusions: This study showed that the FlaC protein possesses a significant immunogenicity and immune protection effect and obtained the optimal fermentation conditions. It is expected to be a potential vaccine against V. alginolyticus and V. parahaemolyticus ., (Copyright: © 2019 The Author(s); Published by National Institute of Genetic Engineering and Biotechnology.)

Lysozyme, an important antibacterial protein, is an enzyme that cleaves the glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine of peptidoglycan in cell walls. The novel lysozyme was purified and characterized from Chinese Lueyang black-bone silky fowl (CBSF) egg white, and its N-terminal amino acid sequence, enzymatic properties, and antibacterial activity were investigated. The CBSF lysozyme was purified using adsorption chromatography, ammonium sulfate precipitation, ion exchange chromatography, and size-exclusion chromatography. The purification fold and yield were 3.28 and 14.69%, respectively. The purified lysozyme was revealed as a single protein band with SDS-PAGE and had a MALDI-TOF/TOF molecular weight of 14305.57 Da and a final specific activity of 3.49 × 10 5  U/mg protein using Micrococcus lysodeikticus as a substrate. The optimum temperature and pH of the lysozyme were 50 °C and 6.0, respectively. The 20 N-terminal amino acid residues of the purified lysozyme were determined to be KVFGRCELAAAMKRHGLDNY, showing some homology to the N-terminus of the odontophoridae egg white lysozyme. The purified lysozyme exerted a potent antimicrobial activity toward indicator microorganisms, including Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922. However, its inhibition of gram-negative activity was weaker than that of the Gram-positive bacteria.

In order to protect the genetic resource of native horse breeds, the genetic diversity of mitochondrial DNA (mtDNA) D-loop of three native horse breeds in western China were investigated. Forty-three 600 bp mtDNA D-loop sequences were analyzed by PCR and sequencing techniques, 33 unique haplotypes with 70 polymorphic sites were detected in these horses, which account for 11.67% of 600 bp sequence analyzed, showing the abundant genetic diversity of the three native horse breeds in western China. The Neighbour-Joining (NJ) phylogenetic tree based on 247 bp of 43 D-loop sequences demonstrated the presence of seven major lineages (A to G), indicating that the three native horse breeds in western China originated from multiple maternal origins. Consistent with the front, the NJ phylogenetic tree based on 600 bp of mtDNA D-loop sequences of 43 Chinese western native horses and 81 sequences of six horse breeds from GenBank indicated that the three horse breeds had distributed into the seven major lineages (A to G). The structure of the phylogenic tree is often blurred because the variation in a short segment of the mitochondrial genome is often accompanied by high levels of recurrent mutations. Consequently, longer D-loop sequences are helpful in achieving a higher level of molecular resolution in horses.

Antibacterial peptides are a family of host-defense peptides most of which are gene-encoded and produced by living organisms of all types. Antibacterial peptides are small molecular proteins with broad antimicrobial spectrum against bacteria, viruses, fungi and sometimes even as anticancer peptide. SMAP-29, a cathelicidin-like peptide derived from sheep myeloid, line alpha-helical Structure, exerts a powerful broad antimicrobial activity against different pathogens including Gram-positive and Gram-negative bacteria, fungi, viruses, parasites, spirochaetes, chlamydia and antiendotoxin activity, and particular antibacterial mechanism, rapidly to permeabilize membranes of susceptible organisms. This paper summarizes the lately research progress of SMAP-29 and Variants including the characteristics of structure, structure-activity relationships, mode of action, diverse biological functions, gene recombinant and expression. We put emphasis on the necessity of molecular design, and primary and secondary structure-based modification, to provides a strong foundation for further drug development and design of SMAP-29.