Angelica archangelica and Ginkgo biloba Extracts Recover Functional Blood Hemoglobin Derivatives in Rabbits Exposed to High Altitude

Background: Shortage of oxygen is a common condition for residents of high-altitude (HA) areas. In mammals, hemoglobin (Hb) has four derivatives: oxyhemoglobin (Hb-O-2), carboxyhemoglobin (Hb-CO), sulfhemoglobin (Hb-S), and methemoglobin (Met-Hb). In HA areas, aberrant physiological performance of blood hemoglobin is well-established. Objectives: The study aimed to investigate the influence of 30 days of HA residence on rabbits' total Hb, Hb derivatives, Hb autooxidation rate, and antioxidant enzymes in comparison to low-altitude control rabbits. Further, the study aimed to investigate the effect of antioxidant-rich Angelica archangelica and/or Ginkgo biloba extracts on the same parameters in HA-resident rabbits. Methods: Rabbits subjected to 30 days of HA residence were compared to low-altitude control rabbits. HA-residence rabbits were then orally administered 0.11 g/kg b.wt. of Angelica archangelica and/or Ginkgo biloba extract for 14 days. Hb derivatives and Hb autooxidation rate were measured spectrophotometrically. Antioxidant enzymes were estimated using specialized kits. Results: Compared to low-altitude rabbits, 30-day HA-residence rabbits showed a noticeable increase (p<0.05) in Hb-O-2 and Hb-CO concentration. In addition, Met-Hb concentration, autooxidation rate of Hb molecules, and activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) exhibited a remarkable increase in HA-residence rabbits (p<0.01), reflective of rapid ROS generation. In HA-residence rabbits, both individual and combined treatment with antioxidant-rich extracts for 14 days resulted in recovery to near-normal functional levels of Hb-O-2 and Met-Hb, Hb autooxidation rate, and activities of SOD and GPx, while only combined treatment led to Hb-O-2 recovery. Conclusion: The findings suggest that functional Hb levels may be recovered by oral administration of A. archangelica, G. biloba, or combined treatments. In conclusion, oxidative stress due to living in HA areas may be avoided by supplementation with natural antioxidants.

Automated summary

This study investigated the influence of living in high-altitude areas on rabbits' hemoglobin levels and antioxidant enzymes. It found that living in high-altitude areas led to abnormal hemoglobin levels and increased oxidative stress. However, supplementation with antioxidant-rich extracts such as Angelica archangelica and Ginkgo biloba helped restore normal hemoglobin levels and reduce oxidative stress.