OBJECTIVES: Recent evidence suggests that the gut may be a primary site of metformin action. However, studies on the effects of metformin on gut microbiota remain limited, and its impact on gut microbial metabolites such as short-/medium-chain fatty acids is unclear. This study aims to investigate the effects of metformin on gut microbiota, short-/medium-chain fatty acids, and associated metabolic benefits in high-fat diet rats. METHODS: Twenty-four Sprague-Dawley rats were randomly divided into 3 groups: 1) Normal diet group (ND group), fed standard chow; 2) high-fat diet group (HFD group), fed a high-fat diet; 3) high-fat diet + metformin treatment group (HFD+Met group), fed a high-fat diet for 8 weeks, followed by daily intragastric administration of metformin solution (150 mg/kg body weight) starting in week 9. At the end of the experiment, all rats were sacrificed, and serum, liver, and colonic contents were collected for assessment of glucose and lipid metabolism, liver pathology, gut microbiota composition, and the concentrations of short-/medium-chain fatty acids. RESULTS: Metformin significantly improved HFD-induced glucose and lipid metabolic disorders and liver injury. Compared with the HFD group, the HFD+Met group showed reduced abundance of Blautia, Romboutsia, Bilophila, and Bacteroides, while Lactobacillus abundance significantly increased (all P<0.05). Colonic contents of butyric acid, 2-methyl butyric acid, valeric acid, octanoic acid, and lauric acid were significantly elevated (all P<0.05), whereas acetic acid, isoheptanoic acid, and nonanoic acid levels were significantly decreased (all P<0.05). Spearman correlation analysis revealed that Lactobacillus abundance was negatively correlated with body weight gain and insulin resistance, while butyrate and valerate levels were negatively correlated with insulin resistance and liver injury (all P<0.05). CONCLUSIONS Metformin significantly increases the abundance of beneficial bacteria such as Lactobacillus and promotes the production of short-/medium-chain fatty acids including butyric, valeric, and lauric acid in the colonic contents of HFD rats, suggesting that metformin may regulate host metabolism through modulation of the gut microbiota.
Animals ; Metformin/pharmacology* ; Rats, Sprague-Dawley ; Diet, High-Fat/adverse effects* ; Rats ; Gastrointestinal Microbiome/drug effects* ; Male ; Fatty Acids, Volatile/metabolism* ; Fatty Acids/metabolism*

Objective:To investigate the value of CT multiplanar reconstruction (MPR) in the diagnosis of stage Ⅲ pneumoconiosis and complications.Methods:In September 2020, 94 patients with stage Ⅲ pneumoconiosis in Guangzhou 12th people's hospital were selected for digital radiography (DR) and MPR. The detection rate of the number of large shadows and the incidence of related complications were compared and analyzed. The counting data were expressed by frequency and percentage (%) , and the comparison was performed by chi square test.Results:178 and 132 large shadows were detected in MPR and DR chest films respectively. Compared with Dr examination, MPR had higher detection rates of pneumoconiosis related complications such as pulmonary tuberculosis, emphysema, pleural thickening, adhesion, pneumonia, pleural effusion, enlargement of hilar and mediastinal lymph nodes and calcification ( P<0.05) , There was no significant difference in the detection rate of pulmonary bullae ( P>0.05) . Compared with Dr, MPR had a higher detection rate in the diagnosis of cavity, calcification, bronchiectasis and parascar emphysema ( P<0.05) . Conclusion:MPR is better in detecting large shadow and complications of stage Ⅲpneumoconiosis, and has important value.

Objective:To investigate the value of CT multiplanar reconstruction (MPR) in the diagnosis of stage Ⅲ pneumoconiosis and complications.Methods:In September 2020, 94 patients with stage Ⅲ pneumoconiosis in Guangzhou 12th people's hospital were selected for digital radiography (DR) and MPR. The detection rate of the number of large shadows and the incidence of related complications were compared and analyzed. The counting data were expressed by frequency and percentage (%) , and the comparison was performed by chi square test.Results:178 and 132 large shadows were detected in MPR and DR chest films respectively. Compared with Dr examination, MPR had higher detection rates of pneumoconiosis related complications such as pulmonary tuberculosis, emphysema, pleural thickening, adhesion, pneumonia, pleural effusion, enlargement of hilar and mediastinal lymph nodes and calcification ( P<0.05) , There was no significant difference in the detection rate of pulmonary bullae ( P>0.05) . Compared with Dr, MPR had a higher detection rate in the diagnosis of cavity, calcification, bronchiectasis and parascar emphysema ( P<0.05) . Conclusion:MPR is better in detecting large shadow and complications of stage Ⅲpneumoconiosis, and has important value.