The immunomodulatory effects of probiotics on respiratory viral infections: A hint for COVID-19 treatment?

Abstract

Respiratory virus infections are among the most prevalent diseases in humans and contribute to morbidity and mortality in all age groups. Moreover, since they can evolve fast and cross the species barrier, some of these viruses, such as influenza A and coronaviruses, have sometimes caused epidemics or pandemics and were associated with more serious clinical diseases and even mortality. The recently identified Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a Public Health Emergency of International concern and has been associated with rapidly progressive pneumonia. To ensure protection against emerging respiratory tract infections, the development of new strategies based on modulating the immune responses is essential. The use of probiotic components has substantially increased due to their effects on immune responses, in particular on those that occur in the upper/lower respiratory tract. Superinduction of inflammatory reaction, known as a cytokine storm, has been correlated directly with viral pneumonia and serious complications of respiratory infections. In this review, probiotics, as potential immunomodulatory agents, have been proposed to improve the host's response to respiratory viral infections. In addition, the effects of probiotics on different aspects of immune responses and their antiviral properties in both pre-clinical and clinical contexts have been described in detail.

Potential beneficial role of probiotics on the outcome of COVID-19 patients: An evolving perspective

“…The administration of multilayered probiotics ( L. paracasei, L. plantarum, L. acidophilus, L. delbrueckii , B. longum, B. infantis , B. breve, S. salivarius ) to children admitted to the intensive care unit (ICU) with severe sepsis resulted and was useful to increase anti-inflammatory cytokines (TGF-ß1, IL-10) and the decrease pro-inflammatory cytokine levels (TNF-a, IL-6, IL-12p70, IL-17) [ 14 , 29 , 51 ]. The administration of more than twenty probiotics has demonstrated to improved anti-inflammatory interleukins levels and anti-viral antibodies production, reducing the viral load [ [51] , [52] , [53] , [54] ]. For instance, Lactobacillus delbrueckii ssp.…”

We and herbivores eat endophytes

“…Coprophagy (faeces ingestion) is a shortcut in the cycle, as well as the transfer of insect bacteria to the plant during feeding or direct acquisition of bacteria from soil. (Chai et al, 2013;Mahooti et al 2020;Baud et al, 2020). However, probiotics constitute only transient members of the gut microbiota, remaining short periods in the gastrointestinal tract (Zmora et al, 2018) as we suppose some endophytes would do.…”

Dysbiosis in Pediatrics Is Associated with Respiratory Infections: Is There a Place for Bacterial-Derived Products?

“…In the present context of COVID-19 pandemic that affects both the respiratory and the intestinal tract in children, preserving the host microbiota or complement its functionality with probiotics or BLs might mitigate SARS-CoV-2 effects. No evidence is currently available, but this intuitive thinking is intriguing and has triggered the interest of the medical community [ 90 ] as well as that of researchers.…”