Magnesium isoglycyrrhizinate inhibits airway inflammation in rats with chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a kind of chronic lung diseases with the characteristics of airway remodeling and airflow obstruction. Magnesium isoglycyrrhizinate (MgIG) is an anti-inflammatory glycyrrhizic acid preparation for treating hepatitis. However, whether MgIG can treat other diseases and its action mechanism is still obscure. In this study, we evaluated the anti-inflammatory effect of MgIG in rats with COPD and investigated the underlying mechanisms. METHODS: Rat model of COPD was constructed by endotracheal-atomized lipopolysaccharide exposure and cigarette smoke induction. Rats were randomly divided into 5 groups: control group, COPD model group, salmeterol fluticasone comparator group, low dose of MgIG group, and high dose of MgIG group. Except for normal control group, the other four groups received sensitization treatment by cigarette smoking and endotracheal-atomization of endotoxin lipopolysaccharide to construct COPD rats model. After model established successfully, the COPD rats in each group received corresponding dose of endotracheal-atomized normal saline, salmeterol fluticasone, and MgIG every day prior to exposure of cigarette smoke from days 30 to 45. Normal control group were treated with normal saline. Finally, All rats were euthanatized. Pulmonary function was measured. Cells in bronchoalveolar lavage fluid were classified, inflammatory factors IL-6 and TNF-α were determined, histopathological analysis was performed by HE staining, and expression of NLRP3 and cleaved caspase-1 in the lung tissue was also determined by Western blotting. RESULTS: It showed that MgIG treatment (0.40 or 0.80 mg/kg/day) could recover the weight and the clinical symptoms of rats with COPD, accompanied with lung inflammation infiltration reduction, airway wall attenuation, bronchial mucus secretion reduction. Additionally, MgIG administration reduced inflammatory cells (white blood cells, neutrophils, lymphocytes and monocytes) accumulation in bronchoalveolar lavage fluid and decreased IL-6 and TNF-α production in the serum of COPD rats. Furthermore, MgIG treatment also reduced the expression level of NLRP3 and cleaved caspase-1. CONCLUSION: It indicate that MgIG might be an alternative for COPD treatment, and its mechanism of action might be related to the suppression of NLRP3 inflammasome.

A narrative review of COVID-19: magnesium isoglycyrrhizinate as a potential adjuvant treatment.

Coronavirus disease 2019 (COVID-19) has become a global pandemic affecting more than 200 countries with 87 million patients worldwide as of January 7, 2021. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) replicates in a large amount and reaches high-titer levels in a short time after the infection. COVID-19 caused by SARS-CoV-2 shows clinical symptoms mainly including fever, fatigue, dry cough, and dyspnea. In more severe COVID-19 patients, viral pneumonia characterized by bilateral ground glass or patchy opacity, may lead to acute respiratory distress syndrome (ARDS), cytokine storm, multi-organ damage, and even death. Unfortunately, there is no effective therapy for COVID-19 until now. Magnesium isoglycyrrhizinate (MgIG), a magnesium salt of 18-α glycyrrhizic acid stereoisomer, belongs to the fourth generation of glycyrrhizic acid preparation. MgIG has various pharmacological activities including anti-inflammation, anti-oxidation, anti-virus, and immunoregulation, showing the protection against the injury of the vital organs (such as kidney, heart, and lung). Clinically, MgIG injection is usually used as a hepatoprotective agent to treat liver diseases. This narrative review summarizes the research and application of MgIG, and provides the evidence supporting the recommended MgIG as supportive therapy in the "Management Standard for Mild and Common Patients of Coronavirus Disease 2019 (COVID-19) (Second Edition)", which is jointly issued by National Health Commission of People's Republic of China and National Administration of Traditional Chinese Medicine.