Development, validation and application of an HPLC method for reduced vitamin C qualification in HBOCs solution

Therapeutic hypothermia effectively reduces elevated extracellular ascorbate concentrations caused by acute spinal cord injury

In recent years, systemic hypothermia has taken the spotlight for its use in spinal cord injury (SCI) research fields, but detailed molecular mechanisms are still not fully understood. In this study, we use an online-electrochemical system (OECS) to in vivo continuously monitor the ascorbate of the rats' spinal cord. We find that the basal level of ascorbate in rat spinal cord is 1.85 ± 0.88 μmol L^-1 (n = 20). It increased immediately after SCI and reached 2.36 ± 0.65 μmol L^-1 (164.90% ± 7.99% of the basal level) (n = 5) at 60 min after the injury. The SCI-induced extracellular ascorbate increase is obviously attenuated by therapeutic hypothermia (28 °C) after injury and ascorbate returns to 3.01 ± 0.59 μmol L^-1 (100.24% ± 5.02% of the basal level) (n = 5), at 60 min after SCI. These results substantially manifest that the OECS for ascorbate detection could be employed as a platform for understanding the pathological changes during spinal cord injury. This study provides experimental evidence for the essential roles of ascorbate in SCI which could serve as a biomarker for SCI. Our findings also raise the possibility that therapeutic hypothermia can effectively exert neuroprotection in the acute phase of SCI.

Dual effects include antioxidant and pro-oxidation of ascorbic acid on the redox properties of bovine hemoglobin

The oxidation reactions have become the main obstacle of development of bovine hemoglobin-derivates products. Herein, the effects of vitamin C (Vc), a easily available natural antioxidant reagent, on the redox reaction of bovine hemoglobin were systematically investigated through methemoglobin (MetHb) formation and spectrophotometric analysis and oxygen affinity monitoring of hemoglobin. The results showed that Vc presented antioxidant effects in the initial stage of reaction and then could accelerated the MetHb content increasing by production of hydrogen peroxide, which can be indirectly characterized by the formation of choleglobin in the following side reactions. The dual effects of Vc include antioxidant and pro-oxidant effects could be confirmed by the spectrophotometric spectrums analysis in this research. The results of this research supplied the novel insight into understanding of redox properties of bovine hemoglobin and also revealed the main obstacle in exploration of Vc application in the future development of bovine hemoglobin-derivates products.