Dietary sodium selenite affects host intestinal and systemic immune response and disease susceptibility to necrotic enteritis in commercial broilers

Induction of Endogenous Antimicrobial Peptides to Prevent or Treat Oral Infection and Inflammation

Antibiotics are often used to treat oral infections. Unfortunately, excessive antibiotic use can adversely alter oral microbiomes and promote the development of antibiotic-resistant microorganisms, which can be difficult to treat. An alternate approach could be to induce the local transcription and expression of endogenous oral antimicrobial peptides (AMPs). To assess the feasibility and benefits of this approach, we conducted literature searches to identify (i) the AMPs expressed in the oral cavity; (ii) the methods used to induce endogenous AMP expression; and (iii) the roles that expressed AMPs may have in regulating oral inflammation, immunity, healing, and pain. Search results identified human neutrophil peptides (HNP), human beta defensins (HBD), and cathelicidin AMP (CAMP) gene product LL-37 as prominent AMPs expressed by oral cells and tissues. HNP, HBD, and LL-37 expression can be induced by micronutrients (trace elements, elements, and vitamins), nutrients, macronutrients (mono-, di-, and polysaccharides, amino acids, pyropeptides, proteins, and fatty acids), proinflammatory agonists, thyroid hormones, and exposure to ultraviolet (UV) irradiation, red light, or near infrared radiation (NIR). Localized AMP expression can help reduce infection, inflammation, and pain and help oral tissues heal. The use of a specific inducer depends upon the overall objective. Inducing the expression of AMPs through beneficial foods would be suitable for long-term health protection. Additionally, the specialized metabolites or concentrated extracts that are utilized as dosage forms would maintain the oral and intestinal microbiome composition and control oral and intestinal infections. Inducing AMP expression using irradiation methodologies would be applicable to a specific oral treatment area in addition to controlling local infections while regulating inflammatory and healing processes.

Advances in the Study of the Mechanism by Which Selenium and Selenoproteins Boost Immunity to Prevent Food Allergies

Selenium (Se) is an essential micronutrient that functions in the body mainly in the form of selenoproteins. The selenoprotein contains 25 members in humans that exhibit a number of functions. Selenoproteins have immunomodulatory functions and can enhance the ability of immune system to regulate in a variety of ways, which can have a preventive effect on immune-related diseases. Food allergy is a specific immune response that has been increasing in number in recent years, significantly reducing the quality of life and posing a major threat to human health. In this review, we summarize the current understanding of the role of Se and selenoproteins in regulating the immune system and how dysregulation of these processes may lead to food allergies. Thus, we can explain the mechanism by which Se and selenoproteins boost immunity to prevent food allergies.

Immunomodulatory roles of selenium nanoparticles: Novel arts for potential immunotherapy strategy development

Current chemotherapy strategies used in clinic appear with lots of disadvantages due to the low targeting effects of drugs and strong side effects, which significantly restricts the drug potency, causes multiple dysfunctions in the body, and even drives the emergence of diseases. Immunotherapy has been proved to boost the body’s innate and adaptive defenses for more effective disease control and treatment. As a trace element, selenium plays vital roles in human health by regulating the antioxidant defense, enzyme activity, and immune response through various specific pathways. Profiting from novel nanotechnology, selenium nanoparticles have been widely developed to reveal great potential in anticancer, antibacterial, and anti-inflammation treatments. More interestingly, increasing evidence has also shown that functional selenium nanoparticles can be applied for potential immunotherapy, which would achieve more effective treatment efficiency as adjunctive therapy strategies for the current chemotherapy. By directly interacting with innate immune cells, such as macrophages, dendritic cells, and natural killer cells, selenium nanoparticles can regulate innate immunity to intervene disease developments, which were reported to boost the anticancer, anti-infection, and anti-inflammation treatments. Moreover, selenium nanoparticles can also activate and recover different T cells for adaptive immunity regulations to enhance their cytotoxic to combat cancer cells, indicating the potential of selenium nanoparticles for potential immunotherapy strategy development. Here, aiming to enhance our understanding of the potential immunotherapy strategy development based on Se NPs, this review will summarize the immunological regulation effects of selenium nanoparticles and the application of selenium nanoparticle-based immunotherapy strategies. Furthermore, we will discuss the advancing perspective of selenium nanoparticle-based potential immunotherapy as a kind of novel adjunctive therapy to enhance the efficiency of current chemotherapies and also introduce the current obstacles for the development of selenium nanoparticles for potential immunotherapy strategy development. This work is expected to promote the future research on selenium nanoparticle-assisted immunotherapy and finally benefit the more effective disease treatments against the threatening cancer and infectious and chronic diseases.

Immunomodulatory effects of selenium-enriched peptides from soybean in cyclophosphamide-induced immunosuppressed mice

In this study, selenium-enriched soybean peptides (<3 kDa, named Se-SPep) was isolated and purified from the selenium-enriched soybean protein (Se-SPro) hydrolysate by ultrafiltration. The in-vivo immunomodulatory effects of Se-SPep were investigated in cyclophosphamide-induced immunosuppressed mice. Se-SPep treatment could alleviate the atrophy of immune organs and weight loss observed in immunosuppressive mice. Besides, Se-SPep administration could dramatically improve total protein, albumin, white blood cell, immunoglobulin (Ig) M, IgG, and IgA levels in blood. Moreover, Se-SPep strongly stimulated interleukin-2 (IL-2), interferon-gamma (IFN-γ), nitric oxide (NO), and cyclic guanosine monophosphate productions by up-regulating mRNA expressions of IL-2, IFN-γ, and inducible NO synthase in spleen tissue. Furthermore, Se-SPep exhibits more effective immunomodulatory activity compared to Se-SPro and SPep. In conclusion, Se-SPep could effectively enhance the immune capacity of immunosuppressive mice. These findings confirm Se-SPep is an effective immunomodulator with potential application in functional foods or dietary supplements.

Selenomethionine ameliorates LPS-induced intestinal immune dysfunction in chicken jejunum

Selenomethionine (SeMet) is a widely used food supplement. However, the research on the effect of SeMet on intestinal immune function is not enough. Therefore, in this experiment, SeMet was added to the diet of chickens, and lipopolysaccharide (LPS) was used as harmful stimulation to study the effect of SeMet on intestinal immune function in chickens. We chose chicken jejunum as the research object. The results showed that LPS treatment decreased the expressions of selenoproteins and induced inflammatory reaction, cytokine disorder, decreases of immunoglobulin levels, heat shock protein expression disorder, and decreases of defensin expression levels in jejunum. However, dietary SeMet can effectively alleviate the above injury caused by LPS. Our results showed that SeMet could improve the intestinal immunity in chickens, and feeding SeMet could alleviate the intestinal immune dysfunction caused by LPS. The application range of SeMet in feed can be roughly given through our experiment; i.e. 0.35-0.5 mg/kg SeMet was effective. We speculated that dietary SeMet could effectively alleviate the intestinal immune dysfunction caused by harmful stimulation and help to resist the further damage caused by harmful stimulation.

Characterization of a novel bacteriophage φCJ22 and its prophylactic and inhibitory effects on necrotic enteritis and Clostridium perfringens in broilers

High necrotic enteritis (NE) incidence and mortality rates in poultry can be caused by Clostridium perfringens (CP) coinfected with Eimeria spp., a causative agent of coccidiosis. Banning of prophylactic use of antibiotics in feed has been accompanied by increased NE outbreaks, resulting in economically devastating losses to the broiler industry. To determine alternatives for controlling NE, we isolated CP-specific bacteriophages (BP), characterized their properties, evaluated their inhibitory effects on pathogenic CP, selected a highly effective phage (φCJ22), and used φCJ22 as a dietary supplement in experimental NE-afflicted broiler chickens. Male broilers (n = 780) were randomly assigned to 60 pens (n = 13 broilers/pen) and into 5 groups [CP-uninfected negative control (NC), basal diet (BD) without CP and BP; CP-infected positive control (PC), BD + CP; and 3 BP groups receiving low- (LP; BD + CP+10⁵ BP), medium- (MP; BD + CP+10⁶ BP), and high-phage (HP; BD + CP+10⁷ BP plaque-forming units/kg) concentrations]. The results showed that MP and HP groups presented an antimicrobial activity toward clinical CP isolate strains, and the groups decreased NE lesions and mortality rates without changes in chicken performance at the end of the experimental period. After CP-challenge body weight gain and feed efficiency were significantly lower in phage-fed groups than that in the PC group (P < 0.05), and NE-associated mortality was the lowest in the HP group (P < 0.001). Moreover, histopathology revealed lesser gastrointestinal mucosal damage in the NC and BP-treated (LP, MP, and HP) groups than that in the PC group, and MP and HP significantly lowered viable CP number in the cecum content by up to 1.24log10 relative to only CP-infected PC group (P < 0.05). These findings suggest that addition of φCJ22 to chicken feed might effectively ameliorate NE, which is accompanied by reduced CP strains in the gut and compensate the performance of NE-afflicted broilers.

Selenomethionine relieves inflammation in the chicken trachea caused by LPS though inhibiting the NF-κB pathway

Selenomethionine is able to relieve the effect of inflammation in various tissues and organs. However, there are few studies about the influences of organic selenium resisting inflammation induced by LPS in chicken trachea. Therefore, the purpose of this experiment is to explore the organic selenium (selenomethionine) can raise immune function and relieve the LPS-induced inflammation of chicken trachea via inhibiting the NF-κB pathway. To investigate the mechanism of organic selenium on chicken trachea, the supplement of selenomethionine and/or LPS-induced chicken models were established. One hundred 46-week-old isa chickens were randomly divided into four groups (n = 25). The four groups were the control group, the selenomethionine group (Se group), the LPS-induced group (LPS group), and the Se and LPS interaction group (Se + LPS group). Then, the expressions of inflammatory factors (including induced nitric oxide synthase (iNOS), nuclear factor-kappa B(NF-κB), tumor necrosis factor (TNF-α), cyclooxygenase-2 (COX-2), and prostaglandin E (PTGEs) synthase), inflammation-related cytokines (including interleukin (IL-2, IL-6, IL-8, IL-17) and immunoglobulin (IgA, IgM, IgY)), the marker of immune function (avian β-defensins (AvBD6, AvBD7)), heat shock proteins (including HSP60, HSP90), and selenoproteins (including Selo, Sels, Selm, Selh, Selu, Seli, SPS2, GPx1, GPx2, Dio1, Sepx1, Sep15, Sepp1, Txnrd1) were detected in our experiment. The above genes were significantly changed in different groups (p < 0.05). We can conclude that organic selenium can increase the function of immunity and the expression of selenoproteins, and mitigate the inflammation induced by LPS via suppression of the NF-κB pathway.

Protective effects of fermented goat milk on genomic stability, oxidative stress and inflammatory signalling in testis during anaemia recovery

Oxidative stress is a harmful factor for male reproductive function, and a major cause of infertility. On the other hand, fermented goat milk has positive effects on anemia recovery and mineral metabolism. This study evaluated the effect of feeding rats with fermented milks during anaemia recovery on molecular mechanisms linked to oxidative stress and inflammatory signalling in rats reproductive system. Forty male Wistar rats were placed on a pre-experimental period of 40 days (control group, receiving normal-Fe diet and Fe-deficient group, receiving low-Fe diet). Lately, rats were fed with fermented goat or cow milk-based diets during 30 days. After feeding the fermented milks, Total antioxidant status (TAS) and non-esterified fatty acids (NEFA) increased and 8-hydroxy-2’-deoxyguanosine (8-OHdG), 15-F2t-isoprostanes and thiobarbituric acid reactive substances (TBARS) decreased in testis. DNA oxidative damage in testis germ cells was lower with fermented goat milk. Fermented goat milk reduced IL-6 and TNF-α in control animals, increasing INF-γ in control and anaemic rats. NRF2 and PGC-1α protein levels increased in testis after fermented goat milk consumption in control and anaemic rats. Fermented goat milk also increased TAS and decreased oxidative damage, protecting the main testis cell bioconstituents (lipids, proteins, DNA, prostaglandins) from oxidative damage and reduced inflammatory activity, preventing injuries to testis germinal epithelium. Fermented goat milk enhanced lipolysis, fatty acids degradation and immune response, attenuating inflammatory signalling, representing a positive growth advantage for testicular cells.

Sodium Selenite Protects Against Silver Nanoparticle-Induced Testicular Toxicity and Inflammation

Metal nanomaterials hold great potential and play an important role in consumer products. However, the increasing use of nanomaterials has raised concern over inadvertent exposure and potential risks for human health and the environment. Henceforth, in vivo testing of nanoparticles and protection against its toxicity is required. Using rat as an animal model, effect of sodium selenite (Se), an essential trace element, on rat testes exposed to silver nanoparticles (AgNPs) was evaluated. Male rats were treated with AgNPs (5 mg/kg/b.w) i/p or Se (0.2 mg/kg/b.w) by gavage. AgNP administration decreased Glutathione (GSH) levels and activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) and increased levels of malondialdehyde (MDA) and expression of interleukin-1 beta (IL-1β), IL-6, and tumor necrosis factor alpha (TNF-α). However, treatment with Se increased GSH levels and activities of SOD, CAT, and GPx compared with AgNP-treated group and decreased the level of MDA and inflammatory biomarkers significantly (p < 0.05) as compared with AgNP-treated group. Light microscopic analyses also revealed that AgNP induced histopathological changes in testes tissue. Further, protection by Se on biochemical results was confirmed by alleviation of the histopathological changes in the tissue. Results show the adverse effects of AgNPs on the male reproductive tract, particularly spermatogenesis, and suggest that Se possesses significant potential in reducing AgNP-induced testicular toxicity.

In Vitro Analysis of the Immunomodulating Effects of Allium Hookeri on Lymphocytes, Macrophages, and Tumour Cells

The present study investigated the effects of ethanol extracts of Allium hookeri (leaf, root, and fermented root) on parameters of innate immunity, tumour cell viability and antioxidant effect in vitro. Innate immunity was measured by spleen lymphocyte proliferation, nitric oxide production by chicken macrophage HD11 cells and suppressive effect on tumour cell viability was assessed using chicken RP9 cells. Free radical scavenging capacity as a measure of antioxidant capacity was determined by 0.15 mM of DPPH solution. In vitro culture of chicken spleen lymphocytes with ethanol extract of Allium hookeri (62.5–500 µg/mL) significantly induced higher proliferation compared with media control. Stimulation of macrophages with ethanol extract of Allium hookeri (62.5–500 µg/mL) showed increased Nitric oxide production. Tumor cells growth was significantly inhibited by extracts of Allium hookeri at 15.6–125 µg/mL compared with medium control and all extracts exhibited greater than 80% scavenging activity at 1000 µg/mL compared with ethanol vehicle control. Above all, fermented root extracts showed strongest effects on antioxidant activity compared to leaf and root extracts.