Iodine-induced synthetic method and pharmacokinetic study of cis- and trans-crocetin.

Objective: This experiment aimed to obtain the relatively rare cis-crocetin isomer from natural plants, which predominantly exist in the more stable all-trans configuration. This was achieved through iodine-induced isomerization, followed by purification and structural identification. The study also aimed to compare the pharmacokinetic differences between cis- and trans-crocetin in vivo. Methods: Trans-crocetin of high purity was extracted by hydrolysis from gardenia yellow pigment. Cis-crocetin was then synthesized through an optimized electrophilic addition reaction induced by elemental iodine, and subsequently separated and purified via silica gel column chromatography. Structural identification of cis-crocetin was determined using IR, UV, and NMR techniques. In vivo pharmacokinetic studies were conducted for both cis- and trans-crocetin. In addition to this, we have conducted a comparative study on the in vivo anti-hypoxic activity of trans- and cis-crocetin. Results: Under the selected reaction conditions using DMF as the solvent, with a concentration of 2.5 mg/mL for both trans-crocetin and the iodine solution, and adjusting the illumination time according to the amount of trans-crocetin, the rate of iodine-induced isomerization was the fastest. Cis-crocetin was successfully obtained and, after purification, its structure was identified and found to be consistent with reported data. Cis-crocetin exhibited a faster absorption rate and higher bioavailability, and despite its shorter half-life, it could partially convert to trans-crocetin in the body, thereby extending the duration of the drug's action within the body to some extent. Conclusion: This study accomplished the successful preparation and structural identification of cis-crocetin. Additionally, through pharmacokinetic studies, it uncovered notable variations in bioavailability between cis- and trans-crocetin. These findings serve as a solid scientific foundation for future functional research and practical applications in this field.

[CiteSpace knowledge map of research status and trends of Croci Stigma].

This study retrieved Croci Stigma related literature from CNKI, Wanfang, VIP, and Web of Science database, and used bibliometrics and CiteSpace 6.1.R2 software to analyze the published Croci Stigma related articles in Chinese and English from 2000 to 2022. The authors, research institutions, and keywords were visualized and analyzed, and the current status and development trend of Croci Stigma research was summarized by combining the information extraction methods. A total of 1 846 Chinese articles and 2 703 English articles were screened out and included. The results showed a generally steady increase in the number of Croci Stigma related articles. The results of the visualization analysis showed that there were more collaborations between researcher teams and major research institutions in English articles than Chinese articles. The Chinese articles was mainly published by China Pharmaceutical University, and most of the inter-institutional collaborations occurred in neighboring regions. The English articles was mainly published by Iranian institutions, and most of the cooperation occurred within the country, with less transnational cooperation. Keywords analysis showed that the research on Croci Stigma was mainly focused on chemical compositions, pharmacological effects, mechanisms, quality control, etc. It was predicted that the future research hotspots of Croci Stigma would mainly focus on pharmacological mechanism and clinical efficacy. The current research related to Croci Stigma still needs to be developed, cooperation should be strengthened, and more in-depth research should be conducted.

Exercise performance reduction and preventive measures in highland sports. / 高原运动效能降低及防治措施.

The plateau is a special environment with low pressure, low oxygen, low temperature, and high ultraviolet radiation. The exercise performance of people on the plateau is generally reduced, which seriously affects the life and health of people living in the plateau and entering the plateau. In recent years, the prevention and treatment of injury caused by high altitude hypoxia has attracted wide attention. It has shown that the higher the altitude with the longer the duration of exercise, the faster the stationing, the greater the impact on people's sports performance. Rapid entry into the plateau and long-term stay in the plateau have an impact on people's explosive power, endurance and fine operation. Advances in medical technology enable various prevention methods to be used to acclimate to high altitude environments. However, in vitro intervention methods are costly, easy to rebound and possess limited effects. Therefore, drug prevention and treatment is obviously a more economical choice. Chemical drugs increase the efficiency of high altitude exercise by improving the ischemic and hypoxic symptoms of the heart and brain, increasing lung ventilation and arterial oxygenation capacity, and accelerating the elimination of adverse product accumulation after exercise. Single Chinese medicine, Chinese patent medicine, and compound preparations can improve exercise performance by promoting body metabolism, improving muscle endurance, enhancing immunity, and other mechanisms. Traditional Chinese medicine has unique advantage and application prospect in improving plateau sports performance damage.