Dietary zinc and the control of Streptococcus pneumoniae infection

Abstract

Human zinc deficiency increases susceptibility to bacterial infection. Although zinc supplementation therapies can reduce the impact of disease, the molecular basis for protection remains unclear. Streptococcus pneumoniae is a major cause of bacterial pneumonia, which is prevalent in regions of zinc deficiency. We report that dietary zinc levels dictate the outcome of S . pneumoniae infection in a murine model. Dietary zinc restriction impacts murine tissue zinc levels with distribution post-infection altered, and S . pneumoniae virulence and infection enhanced. Although the activation and infiltration of murine phagocytic cells was not affected by zinc restriction, their efficacy of bacterial control was compromised. S . pneumoniae was shown to be highly sensitive to zinc intoxication, with this process impaired in zinc restricted mice and isolated phagocytic cells. Collectively, these data show how dietary zinc deficiency increases sensitivity to S . pneumoniae infection while revealing a role for zinc as a component of host antimicrobial defences.

Zinc and respiratory tract infections: Perspectives for COVID‑19 (Review)

“…Zinc is an essential component of antibacterial immunity (5). Particularly, Zn deficiency was associated with reduced killing activity of phagocytes in pneumococcal infection (131). In turn, Zn supplementation ameliorated the association between nasopharyngeal S. pneumoniae carriage and acute lower respiratory infection in children (132).…”

The Potential Impact of Zinc Supplementation on COVID-19 Pathogenesis

“…About 50% of patients that died of COVID-19 had bacterial or fungal co-infections ( 145 ), underlining the importance of sustaining the immune function by a sufficient zinc supply ( 1 , 2 , 36 ). In animal experiments it was shown that zinc restriction made mice highly susceptible to bacterial infection with streptococcus pneumoniae ( 146 ). As mentioned earlier, marginal zinc deficiency affects one third of the worldwide population and most subjects with COVID-19 are at risk of zinc deficiency ( Figure 1 ).…”

RNA-based thermoregulation of a Campylobacter jejuni zinc resistance determinant

“…Zn(II) levels are also reported to increase in the various host niches colonised by Streptococcus pneumoniae to inhibit bacterial growth [ 20 ] and dietary Zn(II) restriction impacts on the ability of phagocytes to control S . pneumonia infection by Zn(II) intoxication [ 21 ]. Furthermore, high levels of both calprotectin and Zn(II) are found at skin sites colonised by group A Streptococcus , with bacterial control being associated with both extracellular Zn(II) chelation by calprotectin and intracellular Zn(II) intoxication following phagocytosis [ 22 ].…”