Serum zinc level in bronchial asthma

The Yin and Yang of ACE/ACE2 Pathways: The Rationale for the Use of Renin-Angiotensin System Inhibitors in COVID-19 Patients

“…In addition, serum albumin levels in COVID-19 were usually very low (in severe forms is usually < 3.1 g/dL) [6,8], raising the possibility of a negative correlation between albumin concentration in plasma and increase of the RAS activity. In line with these hypotheses, both asthmatic/allergic disease patients and chronic kidney disease patients without a history of cardiovascular disease, which are protected from developing COVID-19, showed a significant decrease in both circulating zinc levels and ACE2 activity as compared to normal values [96][97][98][99]. Interestingly, chronic renal disease patients with low zinc levels had normal concentrations of albumin but higher urinary zinc excretion than healthy controls [97], suggesting that low ACE2 activity in chronic renal diseases (and protection from SARS) might derive from a higher free Zn 2+ renal excretion.…”

“…Interestingly, chronic renal disease patients with low zinc levels had normal concentrations of albumin but higher urinary zinc excretion than healthy controls [97], suggesting that low ACE2 activity in chronic renal diseases (and protection from SARS) might derive from a higher free Zn 2+ renal excretion. A similar mechanism mediated by a reduction of extracellular levels of free Zn 2+ might be hypothesised for asthma patients, as well [98]. Unfortunately, I could not find information on plasma albumin concentrations for asthma patients; nevertheless, we might suppose that in these patients the albumin concentration is in normal range.…”

“…On the other hand, increased ACE2 protein expression was reported in plasma and/or urine of physically active men after acute aerobic training or in renal cortices of spontaneous hypertensive, but not normotensive, rats after chronic aerobic training [149,150]. In addition, recent works reveal that asthma and other allergic diseases, which protect from developing COVID-19, were associated with significant reductions in levels of both zinc in plasma and ACE2 mRNA in airway cells [98,99]. On the other hand, as already mentioned, some patients with cardiovascular diseases (and inflammatory bowel disease) have an increased circulating ACE2 [22,49,151,152], which might explain the higher probability of elderly heart patients to develop COVID-19.…”

Lower circulating zinc and selenium levels are associated with an increased risk of asthma: evidence from a meta-analysis

“…Thus, twenty-two articles with twenty-six studies provided results for Zn level (5,7,8,10,(12)(13)(14)(15)(16)(17)(25)(26)(27)(30)(31)(32)(33)(34)(35)(36)(37)(38) and twenty-four articles with forty studies provided results for Se level (5,(9)(10)(11)13,16,25,28,29,31,32,35,(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48) . The detailed characteristics of the included studies are shown in the online supplementary material, Supplemental File S1 for Zn and Supplemental File S2 for Se.…”

“…Considering the unexplained heterogeneity and potential small-study effect, sensitivity analysis using I 2 > 50 % as the criterion was conducted to assess the robustness of conclusion. Six and seven studies contributed to the high heterogeneity of Zn (7,8,10,17,25,38) and Se (10,11,35,38,42,45,47) , respectively. After excluding these studies, low heterogeneity and robust results without small-study effect were found for Zn (…”