Xanthones as potential α-glucosidase non-competition inhibitors: Synthesis, inhibitory activities, and in silico studies.

α-glucosidase inhibitors (AGIs) were commonly used in clinical for the treatment of type 2 diabetes. Xanthones were naturally occurring antioxidants, and they may also be potential AGIs. In this study, eleven 1,6- and 1,3-substituted xanthone compounds were designed and synthesized, of which four were new compounds. Their α-glucosidase inhibitory activities in vitro and in silico were evaluated. Five xanthone compounds with higher activity than acarbose were screened out, and the xanthones substituted at the 1,6-positions were more likely to be potential α-glucosidase non-competitive inhibitors. The binding mode of xanthones with α-glucosidase was further studied by molecular docking method, and the results showed that the inhibitory effect of non-competitive inhibitors on site 1 of α-glucosidase may be related to the hydrogen bonds formed by the compounds with amino acid residues ASN165, HIS209, TRY207, ASP243, and SER104. This study provided a theoretical basis of the rapid discovery and structural modification of non-competitive xanthone inhibitors of α-glucosidase.

Traditional Chinese Herbal Medicine for Allergic Diseases: A Review.

The prevalence of allergic disorders has increased in recent years, lowering patients' quality of life and increasing the demand for drugs to treat these diseases. Western drugs such as glucocorticoids, antihistamines, and leukotrienes are routinely utilized in clinics. However, drawbacks like high recurrence rates and adverse effects limit their use. As one of the most promising natural medicine systems, traditional Chinese medicine offers distinct benefits in treating allergic illnesses, such as maintaining long-term treatment, preventing disease recurrence, and producing fewer adverse reactions. We analyzed and discussed recent developments in traditional Chinese medicine used in allergic diseases from three perspectives: Chinese herbal formula, Chinese patent medicine, and active ingredients of traditional Chinese medicine, and explained their main components, efficacy, and mechanisms of action. We also reviewed the modification of Chinese herbal formulas and the combined application of Chinese medicine with Western medicine or nonpharmaceutical therapies. Traditional Chinese medicines are becoming increasingly important in treating allergic disorders. Improving traditional Chinese herbal formulas and developing safe and effective Chinese patent medicines are currently the most pressing and important aspects of research on traditional Chinese medicine.

Discovery and Activity Evaluation of the Inhibitory Effect of Four Kinds of Traditional Chinese Medicine Extracts on the CYP3A4 Enzyme.

BACKGROUND AND OBJECTIVE: Traditional Chinese medicines that have inhibitory effects on the CYP3A4 enzymes were screened and their inhibitory effects were verified with in vitro bioassay. METHODS: The computer virtual screening methods, including the CYP3A4 enzyme pharmacophore model and the molecular docking method, were used to rapidly screen the potential CYP3A4 inhibitors in the Traditional Chinese Medicine Database (TCMD), and then in vitro experiments were conducted to validate the computational data. RESULTS: A total of 413 chemical components in TCMD that have potential inhibitory effects on the CYP3A4 enzyme were screened, and four kinds of traditional Chinese medicines (Abrus precatorius, Andrographis paniculata, Angelica pubescens f. biserrata and Lithospermum erythrorhizon) contained the most potential CYP3A4 inhibitors; The results of the in vitro experiments showed that these four traditional Chinese medicine extracts all had certain degrees of inhibition on the CYP3A4 enzyme, with IC50 values of 5.15, 14.97, 15.2, and 24.21 µg/ml, respectively. CONCLUSION: The extracts of Abrus precatorius, Andrographis paniculata, Angelica pubescens f. biserrata and Lithospermum erythrorhizon had certain inhibitory effects on the CYP3A4 enzyme, and attention should be paid to the possible adverse reactions when they were used in combination with the CYP3A4 enzyme-substrate drugs. A combination of computational approaches might be a useful tool to identify potential inhibitors of the CYP3A4 enzyme from traditional Chinese medicine.

Dynamic Changes and Regional Differences of Net Carbon Sequestration of Food Crops in the Yangtze River Economic Belt of China.

The carbon sequestration of food crops is of great significance to slow down agricultural greenhouse gas emissions in agricultural production and management. This paper analyzes the dynamic change and regional differences of net carbon sequestration of food crops from temporal and spatial perspectives for the case study area of the Yangtze River economic belt (YREB) in China. We use the calculation formula of carbon sequestration and carbon emission to calculate the net carbon sequestration in the Yangtze River economic belt. On this basis, we analyze the dynamic trend and regional differences of net carbon sequestration in the Yangtze River economic belt. Furthermore, we use the Gini coefficient to measure the quantitative gap of net carbon sequestration of grain crops in different regions of the Yangtze River economic belt. The results show that: (1) from 2000-2018, the net carbon sequestration of food crops keeps rising within the studied area, while the carbon emission shows a fluctuating downward trend; (2) remarkable regional differences in the net carbon sequestration of food crops have occurred, and most provinces (cities) show an upward trend for the studied area; (3) the unequitable distribution of net carbon sequestration of food crops is clearly displayed in the upper, middle, and lower reaches of the studied area. Moreover, the most uneven place is located on the lower reaches, and the least uneven place is in the upper reaches. These findings are important points of reference for reducing the carbon emissions of the agricultural industry in the Yangtze River economic belt of China and in China more generally.