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Background: The traditional Chinese medicine Ligusticum chuanxiong Hort. (CHX) has been used in the management of heart disease, particularly myocardial ischemia (MI), but its related active constituents and mechanisms remain to be further explored. Methods: We analyzed the blood entry constituents of CHX by UPLC-Q-TOF-MS/MS. The protective effects of the constituents on cardiomyocytes were evaluated using isoproterenol (ISO)-treated H9c2 cells to screen for quality markers (Q-markers) of CHX. We used a single-factor and orthogonal experimental design to optimize the extraction process of CHX based on Q-markers. Then, ISO-treated rats were prepared for evaluation of the anti-MI effects of CHX extracts via echocardiography, electrocardiography (ECG), H&E staining, Masson staining, TUNEL staining, and transmission electron microscopy (TEM). Furthermore, the potential mechanisms of CHX in ISO-treated H9c2 cells were explored via western blot assays, flow cytometry analysis, and immunofluorescence assays. Results: A total of 7 blood entry constituents of CHX were identified. All 7 components had protective effects on H9c2 cells and were considered to be Q-markers of CHX. The optimal extraction parameters for CHX were as follows: extraction time, 1.5 h; solid–liquid ratio, 1:20; ethyl alcohol (EtOH) concentration, 80 %; and 3 extraction times. The ECG results showed that CHX could reduce ISO-induced ST segment elevation. Echocardiography revealed that CHX improved heart function and increased fractional shortening (FS) and ejection fraction (EF) in ISO-treated rats. H&E, Masson and TUNEL staining showed that CHX reduced inflammatory infiltration and cell necrosis in heart tissue and reduced cardiac tissue fibrosis and apoptosis. TEM analysis revealed that CHX decreased cardiomyocyte mitochondrial swelling and lipid droplet formation. The in vitro results showed that CHX can prevent apoptosis, protect the mitochondrial membrane potential (MMOP) and reduce oxidative stress in ISO-treated H9c2 cells. Western blot and immunofluorescence results indicated that the mechanism of the anti-MI effect of CHX was related to the regulation of the Dvl-1/Akt/GSK-3β/Nrf2 pathway. The cellular protective effect of CHX can be inhibited by Akt inhibitor MK-2206. Conclusion: Collectively, we optimized the extraction process of CHX, and the optimized CHX showed significant anti-MI effects via regulation of the Dvl-1/Akt/GSK-3β/Nrf2 signaling pathway.

Coronary heart disease (CHD) is the most common clinical manifestation of cardiovascular disease. It is characterized by myocardial ischemia, which is caused by coronary atherosclerosis. CHD is a significant global health problem with increasing prevalence every year because of significant changes in the lifestyles and diets. Ginseng is a traditional Chinese medicinal herb that has been used in food preparations and traditional medicine for several centuries. Several studies have demonstrated that ginseng improved cardiac function by normalizing blood glucose levels and decreasing blood pressure, oxidative stress, platelet aggregation, and lipid dysregulation in vivo. This review describes the current understanding of the mechanisms by which ginseng alleviates CHD, and provides a reference for the clinical development and application of ginseng as an alternative therapy for CHD.

Predators largely affect ecosystems through trophic interactions, but they also can have indirect effects by altering nutrient dynamics and acting as ecosystem engineers. Arctic foxes (Vulpes lagopus) are ecosystem engineers that concentrate nutrients on their dens, creating biogeochemical hotspots with lush vegetation on the nutrient-limited tundra. Red foxes (V. vulpes) similarly engineer subarctic environments through their denning behavior, and have recently expanded onto the tundra where they now often occupy historical Arctic fox dens. We evaluated the impact of fox denning activity on the spatial behavior of other tundra wildlife by comparing predator and herbivore visits to 12 natal dens and adjacent control sites over two years using camera traps in northeastern Manitoba, where both fox species are sympatric. Both the capture rates and species richness of wildlife were significantly greater at fox dens relative to control sites. Predators were detected almost exclusively on dens occupied by foxes, where they were observed investigating and scavenging prey remains (carrion, feathers), suggesting carcass presence or fox presence attracts predators to den sites. Caribou (Rangifer tarandus) also visited dens more often than control sites, likely attracted by the enhanced vegetation typically found on dens. Our results suggest fox ecosystem engineering affects the spatial distribution of herbivores by enriching vegetation at dens, and other predators by providing carrion. Understanding how predators affect other organisms via non-trophic interactions provides an enriched view of their functional roles within ecosystems.

Nursing and weaning periods are poorly understood in cetaceans due to the difficulty of assessing underwater behaviour in the wild. However, the onset and completion of weaning are critical turning points for individual development and survival, with implications for a species' life history including reproductive potential. δ15N and δ13C deposited in odontocete teeth annuli provide a lifetime record of diet, offering an opportunity to investigate variation and trends in fundamental biology. While available reproductive parameters for beaked whales have largely been inferred from single records of stranded or hunted animals and extrapolated across species, here we examine the weaning strategy and nursing duration in northern bottlenose whales (Hyperoodon ampullatus) by measuring stable isotopes deposited in dentine growth layer groups (GLGs). Using a collection of H. ampullatus teeth taken from whales killed during the whaling era (N = 48) and from two stranded specimens, we compared ontogenetic variation of δ15N and δ13C found in annual GLGs across all individuals, by sex and by region. We detected age-based trends in both δ15N and δ13C that are consistent across regions and males and females, and indicate that nursing is prolonged and weaning does not conclude until whales are 3-4 years old, substantially later than previous estimates of 1 year. Incorporating a prolonged period of maternal care into H. ampullatus life history significantly reduces their reproductive potential, with broad implications for models of beaked whale life history, energetics and the species' recovery from whaling.