Inhaled magnesium fluoride reverse bronchospasma

Abstract

Asthma is a global health problem. Asthma attacks are becoming more severe and more resistant to usual treatment by β2 agonists nebulisation. The search for a new product that could reduce the morbidity of asthmatic disease seems necessary. The objective of this study was to compare the effectiveness of inhaled magnesium fluoride (MgF2) with that of magnesium sulphate (MgSO4) 15% alone and sodium fluoride (NaF) 0.5 M alone in rats precontracted by methacholine (MeCh). Fifty six adult male Wistar rats of medium weight 259 ± 15 g were divided randomly into five groups. They inhaled respectively: MeCh, MgF2 + NaCl 0.9%, MgF2 + acetic acid, MgSO4 15% single and NaF (0.5 M) single. Airway resistances were measured after each dose of MeCh by pneumomultitest equipment. Results indicated that (1) MgF2 + NaCl 0.9%, MgF2 + acetic acid and MgSO4 reversed significantly the methacholine-induced bronchial constriction in rats and had a bronchodilating effect at the moment of its administration (2) MgF2 + acetic acid led to a greater decrease (P<0.05) of bronchial resistances when compared to that obtained from MgF2 + NaCl 0.9%, NaF exclusively and MgSO4 alone (3) inhaled NaF alone led to a significant bronchorelaxing effect (P<0.05) that starts at the sixth dose of MeCh (17 mg/L). As a matter of fact, MgF2 dissolved in acetic acid and delivered in aerosol form reduces significantly bronchial spasm. In conclusion, MgF2 can be used as a bronchodilator for diseases with bronchospasma such as asthma and chronic obstructive pulmonary disease (COPD).

Effects of nebulised magnesium sulphate on inflammation and function of the guinea-pig airway

“…This confirms observations that MgSO 4 relaxes rabbit isolated tracheal smooth muscle (Georgoulianis et al, 2001) and bronchoprotection against methacholineinduced bronchoconstriction in rats (Gandia et al, 2010). However, Yoshioka et al 2001and Lindeman et al (1989) would appear that the 250 mM dose produces optimum effect and this relates directly with the inhaled dose used in the MAGNETIC study (Powell et al, 2013).…”

“…The main effect of MgSO 4 is to block the influx of calcium ions into smooth muscle cells of the airways (Georgoulianis et al, 2001) which results in bronchodilatation. One previous study demonstrates bronchoprotective effects of magnesium fluoride and MgSO 4 against inhaled methacholine in rats (Gandia et al, 2010), although Lindeman et al (1985) failed to show any effect of intravenous MgSO 4 against acetylcholine-induced bronchoconstriction in anaesthetized dogs. There is evidence that MgSO 4 may also act as an antiinflammatory agent by inhibiting the neutrophil respiratory burst in adults with asthma (Cairns and Kraft, 1996).…”

Association between trace elements levels and asthma susceptibility

“…Mg also plays a role in many physiological processes, such as protein folding and enzymatic reactions [54]. Mg could relax the bronchial smooth muscles and airways [55], which could alleviates the symptoms of asthma. Reduced intake of Mg induced the proinflammatory processes, phagocytosis, and ROS production, which could worsen the pulmonary function.…”

Fluoride and Bronchial Smooth Muscle

“…NaF, between 0.5 and 10 mM, induce a concentration-dependent contraction in bovine bronchial smooth muscle (Zhao et al, 1997). NaF at 0.5mM induce a bronchorelaxation effect by decrease of bronchial resistances in rats precontracted by acetylmethylcholine analogs and serum concentration of fluoride was within the usual range in blood samples obtained from rats receiving this drug (Gandia et al, 2010). Inhibitory effect of NaF on glycolytic enzyme enolase can be observed in the 10µM range (Curran et al, 1994) on bacteria, which could be of interest in certain lung diseases.…”

“…Inconsequence, its use as therapeutic agent for asthma disease is very limited despite its bronchodilator effect demonstrated at well defined dose both in vitro and in vivo by recent and previous studies (Gandia F et al, 2010;Rouatbi S et al, 2010;Zhao W & Guenard H, 1997;Zhao et al 2002).…”