Generation of Porcine Angiogenin 4-Expressing Pichia pastoris and Its Protection against Intestinal Inflammatory Injury.

Antimicrobial peptides have been extensively studied as potential alternatives to antibiotics. Porcine angiogenin 4 (pANG4) is a novel antimicrobial peptide in the angiogenin (ANG) family, which may have a regulatory effect on intestinal microflora. The object of present study is obtained pANG4 protein by heterologous expression, so as to explore the biological function of recombinant pANG4 (rpANG4). The pANG4 was expressed in Pichia pastoris (P. pastoris) and anti-inflammatory effects were investigated in intestinal porcine epithelial cell line-J2 (IPEC-J2) and mice. Purified rpANG4 had bacteriostatic activity and did not cause hemolysis or cytotoxicity at concentrations below 128 µg/mL. Purified rpANG4 increased the activity of IPEC-J2 and reduced apoptosis in vitro. rpANG4 reduced the pro-inflammatory gene expression and upregulated tight junction protein gene expression during inflammation. rpANG4 alleviated lipopolysaccharide (LPS)-induced liver and spleen damage, intestinal inflammation, jejunal apoptosis genes' expression, and improved immune function in an in vivo mice model. rpANG4 increased tight junction protein gene expression in jejunum, thereby improving the jejunum intestinal barrier function. In conclusion, rpANG4 had antibacterial activity, inhibited intestinal inflammation, improved intestinal barrier function, and alleviated liver and spleen damage. The current study contributes to the development of antibiotic substitutes and the improvement of animal health.

Yeast culture supplementation of sow diets regulates the immune performance of their weaned piglets under lipopolysaccharide stress.

The aim of this study was to investigate the effect of dietary supplementation of sows with yeast cultures (XPC) during late gestation and lactation on the immune performance of their weaned offspring under lipopolysaccharide (LPS) stress. A total of 40 Landrace × Yorkshire sows (parity 3 to 7) with similar backfat thickness were selected and randomly divided into two treatment groups: a control group (basal diet) and a yeast culture group (basal diet + 2.0 g/kg XPC). The trial was conducted from day 90 of gestation to day 21 of lactation. At the end of the experiment, 12 piglets with similar weights were selected from each group and slaughtered 4 h after intraperitoneal injection with either saline or LPS. The results showed that the concentrations of interleukin-6 (IL-6) in the thymus and tumor necrosis factor-α in the liver increased significantly (P < 0.05) in weaned piglets after LPS injection. Maternal dietary supplementation with XPC significantly reduced the concentration of inflammatory factors in the plasma and thymus of weaned piglets (P < 0.05). LPS injection significantly upregulated the expression of some tissue inflammation-related genes, significantly downregulated the expression of intestinal tight junction-related genes, and significantly elevated the protein expression of liver phospho-nuclear factor kappa B (p-NF-κB), the phospho-inhibitory subunit of NF-κB (p-IκBα), phospho-c-Jun N-terminal kinase (p-JNK), Nuclear factor kappa-B (NF-κB), and the inhibitory subunit of NF-κB (IκBα) in weaned piglets (P < 0.05). Maternal dietary supplementation with XPC significantly downregulated the gene expression of IL-6 and interleukin-10 (IL-10) in the thymus and decreased the protein expression of c-Jun N-terminal kinase (JNK) in the liver of weaned piglets (P < 0.05). In summary, injection of LPS induced an inflammatory response in weaned piglets and destroyed the intestinal barrier. Maternal dietary supplementation of XPC improved the immune performance of weaned piglets by inhibiting inflammatory responses.

Weaning older, more mature pigs helps prevent many of the adverse gastrointestinal effects associated with weaning stress, and maternal nutritional interventions can influence offspring gut health and growth performance. Therefore, it is important to explore the effects of maternal nutritional interventions on their offspring. Yeast cultures are a class of biological products consisting of metabolites produced during the anaerobic fermentation of yeast and some live yeast cells, and function to maintain the intestinal health of animals and improve production performance. The effect of sow dietary supplementation with yeast cultures on the immune performance of their weaned offspring under lipopolysaccharide stress has not so far been reported. This study provided a basis for understanding the effects of maternal transfer of yeast cultures to their offspring and provided data to support the application of yeast cultures in actual production.

Dual "Unlocking" Strategy to Overcome Inefficient Nanomedicine Delivery and Tumor Hypoxia for Enhanced Photodynamic-Immunotherapy.

Lacking blood vessels is one of the main characteristics of most solid tumors due to their rapid and unrestricted growth, which thus causes the inefficient delivery efficiency of nanomedicine and tumor hypoxia. Herein, a dual "unlocking" strategy to overcome these obstacles is proposed by combining engineered hybrid nanoparticles (named ZnPc@FOM-Pt) with dexamethasone (DXM). It is verified that pretreatment of tumors with DXM can increase intratumorally micro-vessel density (delivery "unlocking") to enhance the tumor delivery efficiency of ZnPc@FOM-Pt and decrease HIF-1α expression. Correspondingly, more Pt can catalyze tumor-overexpressed H2 O2 to produce oxygen to further cause hypoxia "unlocking," ultimately achieving boosted ZnPc-based photodynamic therapy in vivo (tumor inhibition rate: 99.1%). Moreover, the immunosuppressive tumor microenvironment is efficiently reversed and the therapeutic effect of anti-PD-L1-based immunotherapy is promoted by this newly designed nanomedicine. This dual "unlocking" strategy provides an innovative paradigm on simultaneously enhancing nanomedicine delivery efficacy and hypoxia relief for tumor therapy.

One-pot fabrication of a polydopamine-based nanoplatform for GSH triggered trimodal ROS-amplification for cancer therapy.

Reactive oxygen species (ROS) based nanoplatforms have been considered as attractive and feasible candidates for cancer therapy. However, the activated endogenous antioxidant defense of cancer cells in response to the ROS attack greatly hinders their therapeutic efficacy. Although cancer-specific ROS amplification strategies have been widely explored, most of them suffer from tedious synthesis procedures and complex components, which will bring about undesired side effects and unsatisfactory results. Herein, we design a cancer-specific oxidative stress amplification nanomedicine (CA-Cu-PDA), which is simply fabricated through integrating the glutathione (GSH) responsive/depleting nanocarrier of copper-polydopamine (Cu-PDA) nanoparticles with a ROS-generating drug cinnamaldehyde (CA) via a facile one-pot polymerization route. It is verified that GSH could trigger the breakage of CA-Cu-PDA networks and the subsequent release of both copper ions and CA in cancer cells. The released copper ions efficiently oxidize GSH, thereby weakening the antioxidant system of cancer cells and increasing the ROS levels. On the other hand, extra ROS are generated by the reduced copper ions through a Fenton reaction, so that a synergistic ROS therapy with CA is achieved. Consequently, oxidative stress is specifically increased within cancer cells, leading to efficient cancer cell apoptosis, significant tumor suppression and minimized side effects. Such an ingenious structure realizes the interlocking cooperation and full utilization of each component's function, presenting promising perspectives for nanomedicine design.

2-Hydroxy-4-Methylselenobutanoic Acid Promotes Follicle Development by Antioxidant Pathway.

Selenium (Se) is assumed to promote the follicle development by attenuating oxidative stress. The current study was developed to evaluate the effects of dietary 2-hydroxy-4-methylselenobutanoic acid (HMSeBA) supplementation on the follicle development in vivo and on the function of ovarian granulosa cells (GCs) in vitro. Thirty-six gilts were randomly assigned to fed control diet (CON), Na2SeO3 diet (0.3 mg Se/kg) or HMSeBA diet (0.3 mg Se/kg). The results showed that HMSeBA and Na2SeO3 supplementation both increased the total selenium content in liver and serum compared with control, while HMSeBA increased the total selenium content in liver compared with Na2SeO3 group. HMSeBA tended to increase the total selenium content in ovary compared with control. HMSeBA and Na2SeO3 supplementation both increased the weight of uteri in gilts at the third estrus. Moreover, HMSeBA supplementation down-regulated the gene expression of growth differentiation factor-9 (GDF-9) and bone morpho-genetic protein-15 (BMP-15) in cumulus-oocyte complexes (COCs). HMSeBA supplementation decreased malondialdehyde (MDA) content in serum, liver and ovary, increased activity of T-AOC in liver, TXNRD in ovary and GPX in serum, liver and ovary, while up-regulated the liver GPX2, SOD1 and TXNRD1, ovarian GPX1 gene expression. In vitro, HMSeBA treatment promoted GCs' proliferation and secretion of estradiol (E2). HMSeBA treatment increased the activity of T-AOC, T-SOD, GPX, TXNRD and decreased MDA content in GCs in vitro. Meanwhile, HMSeBA treatment up-regulated SOD2 and GPX1 gene expression in GCs in vitro. In conclusion, HMSeBA supplementation is more conducive to promoting follicle development by antioxidant pathway.