Liver injury caused by an overdose of acetaminophen (APAP) is a major public health problem. This study aimed to evaluate the effects of Broussonetia papyrifera polysaccharide (BPP) on liver injury and intestinal flora induced by APAP. The results showed that BPP could protect against APAP-induced liver injury, alleviate liver apoptosis, improve antioxidant capacity and enhance the liver’s detoxification ability to APAP. At the same time, BPP improved the intestinal flora disorder caused by APAP. More importantly, we found that the hepatoprotective effect of BPP disappeared after the depletion of gut microbiota in mice. Further, we reconstructed the intestinal flora structure of mice through fecal microbiota transplantation and found that the symptoms of APAP—induced liver injury were effectively alleviated. Overall, BPP was a potential hepatoprotective drug that could protect against APAP-induced liver injury and might be mediated by intestinal flora.

Abrus cantoniensis is a Chinese herbal medicine with efficacy in clearing heat and detoxification, as well as relieving liver pain. The whole plant, except the seeds, can be used and consumed. Flavonoids have been found in modern pharmacological studies to have important biological activities, such as anti-inflammatory, antibacterial and antioxidant properties. The antibacterial and antioxidant bioactivities of the total flavonoids of Abrus cantoniensis (ATF) have been widely reported in national and international journals, but there are fewer studies on their anti-inflammatory effects. The present study focused on the optimization of the ultrasonic extraction process of ATF by response surface methodology and the study of its anti-inflammatory effects in vitro and in vivo. The results showed that the factors that had a great impact on the ATF extraction were the material-to-liquid ratio, ultrasonic extraction cycles and ethanol concentration. The best extraction process used a material-to-liquid ratio of 1:47, ultrasonic extraction cycles of 4 times, an ethanol concentration of 50%, an ultrasonic extraction time of 40 min and an ultrasonic power of 125 W. Under these conditions, the actual extraction rate of total flavonoids was 3.68%, which was not significantly different from the predicted value of 3.71%. In an in vitro anti-inflammatory assay, ATF was found to be effective in alleviating LPS (lipopolysaccharide)-induced inflammation in mouse peritoneal macrophages. In an in vivo anti-inflammatory assay, ATF was found to have a significant inhibitory effect on xylene-induced ear swelling in mice and cotton ball granuloma in mice, and the inhibitory effect was close to that of the positive control drug dexamethasone. This may provide a theoretical basis for the further development of the medicinal value of Abrus cantoniensis.

Litsea cubeba L. essential oil (LCEO) can affect the growth of drug-resistance bacteria. However, research on stress response of drug-resistant A. baumannii under sub-lethal LCEO concentrations had been limited so far. Therefore, transcriptomic analysis of A. baumannii under 1/2 minimum inhibitory concentration (MIC, 0.54 mg/mL) of LCEO was performed. Results of transcriptomic analysis showed that 320/352 genes were significantly up/down-regulated, respectively, in LCEO-treated A. baumannii. Both up and down-regulated genes were significantly enriched in three GO terms (oxidation-reduction process; oxidoreductase activity; oxidoreductase activity, acting on the CH-CH group of donors), which indicated that the redox state of A. baumannii was significantly affected by LCEO. LCEO may also inhibit aerobic respiration, synthesis of ketone bodies and the metabolism of some amino acids while, meanwhile, promoting fatty acid degradation of A. baumannii according to Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. The permeability and the stress of cell membrane of A. baumannii were significantly affected by LCEO. After crystal violet dyeing, the biofilm formation of A. baumannii was promoted/inhibited by extremely low/relatively high concentration of LCEO, respectively. LCEO and chloramphenicol have synergistic growth inhibitory effect against A. baumannii according to the Fractional Inhibitory Concentration Index (FICI) value = 0.375. Our results indicate that the growth of A. baumannii was inhibited by LCEO, and give insights into the stress response of A. baumannii under sub-lethal concentrations of LCEO. These results provided evidence that A. baumannii was inhibited by LCEO, and expanded knowledges of stress response of A. baumannii under sub-lethal concentration of LCEO.