The effect of recombinant human lactoferrin from the milk of transgenic cows on Salmonella enterica serovar typhimurium infection in mice

Lactoferrin: Properties and Potential Uses in the Food Industry

Lactoferrin (LF) is an 80 kDa glycoprotein that contains approximately 700 amino acids and is a member of the transferrin family. The essential properties of LF, including antimicrobial, antiviral, anticancer, anti-inflammatory, antioxidant, and probiotic effects, have been studied for decades. The iron chelation activity of LF is significantly associated with its antimicrobial, anti-inflammatory, and antioxidant properties. Owing to its probiotic and prebiotic activity, LF also facilitates the growth of beneficial microorganisms and iron-defense immediate-effect properties on pathogens. Additionally, the ability to regulate cell signaling pathways and immune responses makes LF a prominent modulatory protein. These diverse characteristics of LF have gained interest in its therapeutic potential. Studies have suggested that LF could serve as an alternative source to antibiotics in severe infections and illnesses. LF has also gained interest in the food industry for its potential as an additive to fortify products such as yogurt, infant formula, and meat derivatives while also improving the shelf life of foods and providing antimicrobial and antioxidant activity. Prior to using LF in the food industry, the safety and toxicity of food processing are necessary to be investigated. These safety investigations are crucial for addressing potential harm or side effects and ensuring a healthy lifestyle. This review discusses the attributes and safety of LF, particularly its exploitation in the food industry.

Natural anti-adhesive components against pathogenic bacterial adhesion and infection in gastrointestinal tract: case studies of Helicobacter pylori, Salmonella enterica, Clostridium difficile, and diarrheagenic Escherichia coli

Antimicrobial resistance (AMR) poses a global public health concern. Recognizing the critical role of bacterial adhesion in pathogenesis of infection, anti-adhesive therapy emerges as a promising approach to impede initial bacterial attachment, thus preventing pathogenic colonization and infection. Natural anti-adhesive agents derived from food sources are generally safe and have the potential to inhibit the emergence of resistant bacteria. This comprehensive review explored diverse natural dietary components exhibiting anti-adhesive activities against several model enteric pathogens, including Helicobacter pylori, Salmonella enterica, Clostridium difficile, and three key diarrheagenic Escherichia coli (i.e., enterotoxigenic E. coli, enteropathogenic E. coli, and enterohemorrhagic E. coli). Investigating various anti-adhesive products will advance our understanding of current research of the field and inspire further development of these agents as potential nutraceuticals or adjuvants to improve the efficacy of conventional antibiotics.

Combating antibiotic resistance in a one health context: a plethora of frontiers

One of the most significant medical advancements of the 20th century was the discovery of antibiotics, which continue to play a vital tool in the treatment and prevention of diseases in humans and animals. However, the imprudent use of antibiotics in all fields of One-Health and concerns about antibiotic resistance among bacterial pathogens have raised interest in antibiotic use restrictions on a global scale. Despite the failure of conventional antimicrobial agents, only about 15 new antibiotics have been introduced clinically since year 2000 to date. Moreover, there has been reports of resistance to some of these new antibiotics. This has necessitated a need to search for alternative strategies to combat antimicrobial resistant pathogens. Thus, this review compiles and evaluates the approaches-natural compounds, phage treatment, and nanomaterials-that are being used and/or suggested as the potential substitutes for conventional antibiotics.

Deficiency of Lactoferrin aggravates lipopolysaccharide-induced acute inflammation via recruitment macrophage in mice

Lactoferrin (Lf), a multiple functional natural immune protein, is widely distributed in mammalian milk and glandular secretions (bile, saliva, tears and nasal mucosal secretions, etc.). In the previous study, we found that Lf plays an anti-inflammatory and anti-tumorigenesis role in AOM/DSS (azoxymethane/dextran sulfate sodium) induced mouse colitis-associated colon cancer model. Although we found that Lf has anti-inflammatory effects in chronic inflammation, its specific role and mechanisms in acute inflammation have not been clarified. Here, we reported that the expression levels of Lf were significantly increased when the organism was infected by Gram-negative bacteria. We then explored the role and potential mechanism of Lf in lipopolysaccharide (LPS)-induced acute inflammation. In the LPS-induced acute abdominal inflammation model, Lf deficiency aggravated inflammatory response and promoted macrophage chemotaxis to the inflammation site. Lf inhibited macrophage chemotaxis by suppressing the expression of macrophage-associated chemokines Ccl2 and Ccl5. Highly activated NF-κB signaling in Lf^−/− mice was responsible for the high expression of Ccl2 and Ccl5. Our results suggested that the anti-inflammatory effect of Lf offers a new potential treatment for acute inflammatory diseases.

An Alternative to Antibiotics: Selected Methods to Combat Zoonotic Foodborne Bacterial Infections

Pathogenic bacteria contaminating food or animal feed cause serious economic losses in the health sector as well as is in the agriculture and food industry. The development of bacterial resistance due to the misuse of antibiotics and chemicals, especially in the farm industry, can bring dangerous effects for the global population therefore new safe biological antimicrobial solutions are urgently needed. In this paper, we investigate biological alternatives to antibiotics against foodborne pathogens. The most promising alternatives include antimicrobial proteins, bacteriophages, probiotics, and plant-based substances. Each described group of substances is efficient against specific foodborne bacteria and has a preferred use in an explicit application. The advantages and drawbacks of each method are outlined in the final section. Biological antibacterial solutions are usually easily degradable. In contrast to antibiotics or chemical/physical methods, they are also far more specific. When introducing new antibacterial methods it is crucial to check their safety and ability to induce resistance mechanisms. Moreover, it is important to assess its activity to inhibit or kill in viable but nonculturable cells (VBNC) state and biofilm forms. VBNC bacteria are considered a threat to public health and food safety due to their possibility of remaining viable and virulent. Biological alternatives to antibiotics complete the majority of the advantages needed for a safe and efficient antimicrobial product. However, further research is necessary to fully implement those solutions to the market.

Glycyrrhizin Attenuates Salmonella Typhimurium-Induced Tissue Injury, Inflammatory Response, and Intestinal Dysbiosis in C57BL/6 Mice

Salmonellae are one of the most important foodborne pathogens, which threaten the health of humans and animals severely. Glycyrrhizin (GL) has been proven to exhibit anti-inflammatory and tissue-protective properties. Here, we investigated the effects of GL on tissue injury, inflammatory response, and intestinal dysbiosis in Salmonella Typhimurium-infected mice. Results showed that GL or gentamicin (GM) significantly (P < 0.05) alleviated ST-induced splenomegaly indicated by the decreased spleen index, injury of liver and jejunum indicated by the decreased hepatocytic apoptosis, and the increased jejunal villous height. GL significantly (P < 0.05) increased secretion of inflammatory cytokines (IFN-γ, IL-12p70, IL-6, and IL-10) in spleen and IL-12p40 mRNA expression in liver. Meanwhile, GL or GM pre-infection treatments significantly (P < 0.05) decreased ST-induced pro-inflammatory cytokine (IFN-γ, TNF-α, and IL-6) expression in both spleen and liver and increased (P < 0.05) anti-inflammatory cytokine IL-10 secretion in spleen. Furthermore, GL or GM pre-infection treatment also regulates the diversities and compositions of intestinal microbiota and decreased the negative connection among the intestinal microbes in ST-infected mice. The above findings indicate that GL alleviates ST-induced splenomegaly, hepatocytic apoptosis, injury of jejunum and liver, inflammatory response of liver and spleen, and intestinal dysbacteriosis in mice.

Lactoferrin: A Glycoprotein Involved in Immunomodulation, Anticancer, and Antimicrobial Processes

Lactoferrin is an iron binding glycoprotein with multiple roles in the body. Its participation in apoptotic processes in cancer cells, its ability to modulate various reactions of the immune system, and its activity against a broad spectrum of pathogenic microorganisms, including respiratory viruses, have made it a protein of broad interest in pharmaceutical and food research and industry. In this review, we have focused on describing the most important functions of lactoferrin and the possible mechanisms of action that lead to its function.

The goat β‑casein/CMV chimeric promoter drives the expression of hLF in transgenic goats produced by cell transgene microinjection

There is growing interest in the application of lactoferrin (LF) as a drug or food additive for animals and humans. The objective of this study was to produce transgenic cloned goats that would serve as living bioreactors, expressing high levels of recombinant human LF (rhLF) in their milk. We designed a pCL25 expression vector containing goat β-casein/CMV chimeric promoter in order to facilitate rhLF expression. This pCL25-rhLF-Neo vector was microinjected into goat fetal fibroblasts. G418 selection and PCR analysis were used to identify transgenic donor cells suitable for somatic cell nuclear transfer (SCNT). After SCNT and embryo transplantation, goats harboring the hLF gene were produced, as confirmed via PCR and southern blotting. The average rhLF concentration in milk from this transgenic goat was 3.89 mg/ml as determined via ELISA. We also used an optimized buffer in order to effectively elute high-purity (95.8%) rhLF from a cation-exchange column, with the recovered rhLF exhibiting high biological activity. Findings from this study demonstrated that it is possible to generate a transgenic goat harboring the hLF transgene driven by the goat β-casein/CMV chimeric promoter. It represents an initial step towards the production of rhLF, potentially allowing for industrialized purification in the future.