Tannic acid-mediated immune activation attenuates Brucella abortus infection in mice

Cold plasma treatment of tannic acid as a green technology for the fabrication of advanced cross-linkers for bioactive collagen/gelatin hydrogels

Tannic acid (TA) is a natural compound studied as the cross-linker for biopolymers due to its ability to form hydrogen bonds. There are different methods to improve its reactivity and effectiveness to be used as a modifier for biopolymeric materials. This work employed plasma to modify tannic acid TA, which was then used as a cross-linker for fabricating collagen/gelatin scaffolds. Plasma treatment did not cause any significant changes in the structure of TA, and the resulting oxidized TA showed a higher antioxidant activity than that without treatment. Adding TA to collagen/gelatin scaffolds improved their mechanical properties and stability. Moreover, the obtained plasma-treated TA-containing scaffolds showed antibacterial properties and were non-hemolytic, with improved cytocompatibility towards human dermal fibroblasts. These results suggest the suitability of plasma treatment as a green technology for the modification of TA towards the development of advanced TA-crosslinked hydrogels for various biomedical applications.

Effect of Hydrolyzed Gallotannin on Growth Performance, Immune Function, and Antioxidant Capacity of Yellow-Feather Broilers

Tannins were traditionally considered as anti-nutritional factors in poultry production. Recent studies found that the addition of hydrolyzed gallotannin (HGT) could improve animal health; however, the proper dosage of HGT in chickens' diet is still unknown. Hence, our study aims to recommend its optimal dose by exploring the effects of HGT from Chinese gallnuts on the growth performance, immune function, and antioxidant capacity of yellow-feather broilers. A total of 288 male yellow-feather broilers (34.10 ± 0.08 g) were randomly allocated to four diet treatments, the basal diet with 0 (CON), 150, 300, and 450 mg/kg HGT for 63 days, respectively, with six replications per treatment and 12 birds per replication. The growth performance, slaughter performance, immune organ index, liver antioxidant-related indicators, and serum immune-related factors were evaluated. Results show that HGT supplementation did not influence the growth performance of broilers, but the diets supplemented with 300 and 450 mg/kg HGT increased the semi-eviscerated rate. Furthermore, HGT increased the content of liver T-AOC and the ratio of GSH/GSSG, which can protect against oxidative damage of birds. Additionally, supplementing HGT raised the contents of serum IL-10, IL-4, IL-6, IgA, and IgM. In conclusion, diet supplemented with 450 mg/kg HGT may be the optimal to the health of yellow-feather broilers on the whole.

Plant Phenolics as Pathogen-Carrier Immunogenicity Modulator Haptens

Background

Pathogens use multiple mechanisms to disrupt cell functioning in their host and allow pathogenesis. These mechanisms involve communication between the pathogen and the host cell through protein-protein interactions.

Methods

Protein-protein interactions chains referred to as signal transduction pathways are the processes by which a chemical or physical signal transmits through a cell as series of molecular events so the pathogen needs to intercept these molecular pathways at few positions to induce pathogenesis such as pathogen viability, infection or hypersensitivity.

Results

The pathogen nodes of interception are not necessarily the most immunogenic; so that novel immunogenicity-improvement strategies need to be developed thought a chemical conjugation of the pathogen-carrier nodes to develop an efficient immune response in order to block pathogenesis. On the other hand, if pathogen-carriers are immunogens; toleration ought to be induced by this conjugation avoiding hypersensitivity. Thus, this paper addresses the biological plausibility of plant-phenolics as pathogen-carrier immunogenicity modulator haptens.

Conclusion

The plant-phenolic compounds have in their structure functional groups such as hydroxyl, carbonyl, carboxyl, ester, or ether, capable of reacting with the amino or carbonyl groups of the amino acids of a pathogen-carrier to form conjugates. Besides, the varied carbon structures these phenolic compounds have; it is possible to alter the pathogen-carrier related factors that determine the immunogenicity: 1) Structural complexity, 2) Molecular size, 3) Structural heterogeneity, 4) Accessibility to antigenic determinants or epitopes, 5) Optical configuration, 6) Physical state, or 7) Molecular rigidity.

Plant Phenolics and Lectins as Vaccine Adjuvants

Background:

The immune system is responsible for providing protection to the body against foreign substances. The immune system divides into two types of immune responses to study its mechanisms of protection: 1) Innate and 2) Adaptive. The innate immune response represents the first protective barrier of the organism that also works as a regulator of the adaptive immune response, if evaded the mechanisms of the innate immune response by the foreign substance the adaptive immune response takes action with the consequent antigen neutralization or elimination. The adaptive immune response objective is developing a specific humoral response that consists in the production of soluble proteins known as antibodies capable of specifically recognizing the foreign agent; such protective mechanism is induced artificially through an immunization or vaccination. Unfortunately, the immunogenicity of the antigens is an intrinsic characteristic of the same antigen dependent on several factors.

Conclusion:

Vaccine adjuvants are chemical substances of very varied structure that seek to improve the immunogenicity of antigens. The main four types of adjuvants under investigation are the following: 1) Oil emulsions with an antigen in solution, 2) Pattern recognition receptors activating molecules, 3) Inflammatory stimulatory molecules or activators of the inflammasome complex, and 4) Cytokines. However, this paper addresses the biological plausibility of two phytochemical compounds as vaccine adjuvants: 5) Lectins, and 6) Plant phenolics whose characteristics, mechanisms of action and disadvantages are addressed. Finally, the immunological usefulness of these molecules is discussed through immunological data to estimate effects of plant phenolics and lectins as vaccine adjuvants, and current studies that have implanted these molecules as vaccine adjuvants, demonstrating the results of this immunization.

Tannic Acid Induces the Mitochondrial Pathway of Apoptosis and S Phase Arrest in Porcine Intestinal IPEC-J2 Cells

The presence of tannic acid (TA), which is widely distributed in plants, limits the utilization of non-grain feed. Illustrating the toxicity mechanism of TA in animals is important for preventing poisoning and for clinical development of TA. The aim of the present study was to evaluate the toxic effects and possible action mechanism of TA in porcine intestinal IPEC-J2 cells, as well as cell proliferation, apoptosis, and cell cycle. We investigated the toxic effects of TA in IPEC-J2 cells combining the analysis of TA-induced apoptotic responses and effect on the cell cycle. The results revealed that TA is highly toxic to IPEC-J2 cells. The stress-inducible factors reactive oxygen species, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine were increased in response to TA. Furthermore, TA suppressed mitochondrial membrane potential, reduced adenosine triphosphate production, and adversely affected B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein, caspase-9, caspase-3, cytochrome c, cyclin A, cyclin-dependent kinases, ataxia-telangiectasia mutated, and P53 expression in a dose-dependent manner. We suggest that TA induces the mitochondrial pathway of apoptosis and S phase arrest in IPEC-J2 cells.