What Are Probiotics and Can They Help Enhance Human Health?

  • There are trillions of bacteria and other microorganisms in the human intestine, which together constitute the intestinal microflora. And the gut-associated lymphoid tissue (GALT) contains the vast majority and most complex pool of immune cells. This microflora has a very close interaction with the immune system, and plays an important role in metabolism as well as immunity. More specifically, alterations in its normal composition and pattern of colonization can disturb the development and functioning of the immune system, making individuals susceptible to several diseases.

     

    Probiotics are capable of modulating the intestinal microbiota. Probiotics are a certain number of living microorganisms that play a role in defining and maintaining the delicate balance between necessary and excessive defense mechanisms including innate and adaptive immune responses. They can not only affect the intestinal microecology through the interaction with intestinal symbiotic bacteria or potential pathogenic bacteria and even host cells, but also directly affect the intestinal and even systemic immunity through metabolites.

     

    Studies have shown that probiotics can inhibit potential pathogenic bacteria, improve the intestinal microenvironment, enhance intestinal barrier function, reduce inflammation and enhance antigen-specific immune response. In this regard, studies have shown that some probiotic supplements, such as Lactobacillus casei, are capable of modulating the intestinal microbiota, including reducing pathogenic bacteria and lowering cholesterol. In view of the huge benefits of probiotics, it is very important for researchers to obtain effective probiotics that meet the standards. Therefore, the in vitro test of immune system modulation is an important indicator for screening potential immunoregulatory probiotics strains.

     

    Probiotics, especially second-generation probiotics, also known as live biotherapeutics, have been shown to have beneficial effects on many diseases.

     

    • Vaccination

    The immunomodulatory effects of probiotics may influence the response to vaccines. A study review has revealed the gut microbiota can influence immune responses to vaccinations, suggesting probiotics could be potentially attractive interventions to improve vaccine efficacy. Evidence of a beneficial effect of probiotics on vaccine response is strongest for oral vaccination and parenteral influenza vaccination.

     

    • Allergy and eczema

    Numerous studies have been performed to evaluate the effects of probiotics on allergy prevention and treatment. For example, probiotic consumption increased life performance in allergic rhinitis patients. There were no significant changes in blood or immune parameters in the probiotic community. This suggests probiotics may be useful in allergic rhinitis.

     

    Eczema is a common chronic skin condition. Probiotics have been proposed as an effective treatment for eczema. Various strains of Lactobacillus have had positive results as well. For example, a study found that lotion containing Lactobacillus johnsonii created clinically significant improvement of eczema and reduced staph bacteria on the skin.

     

    • Virus infection

    Viral respiratory and gastrointestinal infections are major health concerns, in particular among children. Accumulating evidence suggests that specific probiotics are able to decrease the risk or duration of respiratory infection symptoms. Lactobacillus rhamnosus GG as next-generation probiotics, has been shown to have the potential to reduce the risk of upper RTIs, the incidence of acute otitis media, and the use of antibiotics.

     

    • Cancer

    The results of many in vitro studies have found that probiotics exhibit beneficial properties in inducing tumor cell apoptosis and inhibiting tumor cell proliferation and metastasis. In animal models, probiotics improve tumor conditions. For example, Lactobacillus rhamnosus GG strain has been shown to inhibit proliferation and induce apoptosis in mouse colon cancer and human colon cancer cells. This positive effect provides a basis for clinical trials.