Intravenous vitamin C administration reduces fatigue in office workers: a double-blind randomized controlled trial.

BACKGROUND: Studies of the efficacy of vitamin C treatment for fatigue have yielded inconsistent results. One of the reasons for this inconsistency could be the difference in delivery routes. Therefore, we planned a clinical trial with intravenous vitamin C administration. METHODS: We evaluated the effect of intravenous vitamin C on fatigue in office workers. A group of 141 healthy volunteers, aged 20 to 49 years participated in this randomized, double-blind, controlled clinical trial. The trial group received 10 grams of vitamin C with normal saline intravenously, while the placebo group received normal saline only. Since vitamin C is a well-known antioxidant, oxidative stress was measured. Fatigue score, oxidative stress, and plasma vitamin C levels were measured before intervention, and again two hours and one day after intervention. Adverse events were monitored. RESULTS: The fatigue scores measured at two hours after intervention and one day after intervention were significantly different between the two groups (p = 0.004); fatigue scores decreased in the vitamin C group after two hours and remained lower for one day. Trial also led to higher plasma vitamin C levels and lower oxidative stress compared to the placebo group (p < 0.001, p < 0.001, respectively). When data analysis was refined by dividing each group into high-baseline and low-baseline subgroups, it was observed that fatigue was reduced in the lower baseline vitamin C level group after two hours and after one day (p = 0.004). The same did not hold for the higher baseline group (p = 0.206). CONCLUSION: Thus, intravenous vitamin C reduced fatigue at two hours, and the effect persisted for one day. There were no significant differences in adverse events between two groups. High dose intravenous vitamin C proved to be safe and effective against fatigue in this study. TRIAL REGISTRATION: The clinical trial registration of this trial is http://ClinicalTrials.govNCT00633581.

Production of human hyaluronidase in a plant-derived protein expression system: plant-based transient production of active human hyaluronidase.

Four types of human hyaluronidases (rHuHyal-1, -2, -3 and -4) were transiently expressed and purified from Nicotiana benthamiana, and their biochemical characteristics were analyzed. The recombinant HuHyals were expressed via agrobacteria-mediated infiltration and generated and expressed in terms of micrograms per 5 leaves of N. benthamiana. Expressed recombinant HuHyals were purified using a His(6) tagging system and Ni column chromatography, respectively, at pH 8.0, after which the purified rHuHyals were concentrated for additional biochemical analyses. The four types of rHuHyals were allowed to react with hyaluronic acids and chondroitin sulfates. The biochemical properties of rHuHyal-1 fit those of the commercially available Hyal, PH-20, which was extracted from animal testes under acidic conditions (pH 3.5). However, rHuHyal-1 evidenced activity levels 2 to 6-fold greater than the three other rHuHyals (rHuHyal-2, -3 and -4) at pH 3.5. However, only rHuHyal-4 exhibited chondroitinase activity with both 6-S-chondroitin sulfate (chondroitin sulfate C) and 4-S-chondroitin sulfate (chondroitin sulfate A) as standard substrates. The results of zymography demonstrated that recombinant HuHyal 1 was modified by glycosylation, but Escherichia coli Hyal was not. This result demonstrated that plant-based rHuHyal was functionally active and evidenced biochemical characteristics and post-translational protein modifications similar to those of animal testis-derived Hyal.

Changes of terminal cancer patients' health-related quality of life after high dose vitamin C administration.

Over the years there has been a great deal of controversy on the effect of vitamin C on cancer. To investigate the effects of vitamin C on cancer patients' health-related quality of life, we prospectively studied 39 terminal cancer patients. All patients were given an intravenous administration of 10 g vitamin C twice with a 3-day interval and an oral intake of 4 g vitamin C daily for a week. And then we investigated demographic data and assessed changes in patients' quality of life after administration of vitamin C. Quality of life was assessed with EORTC QLQ-C30. In the global health/quality of life scale, health score improved from 36+/-18 to 55+/-16 after administration of vitamin C (p=0.001). In functional scale, the patients reported significantly higher scores for physical, role, emotional, and cognitive function after administration of vitamin C (p<0.05). In symptom scale, the patients reported significantly lower scores for fatigue, nausea/vomiting, pain, and appetite loss after administration of vitamin C (p<0.005). The other function and symptom scales were not significantly changed after administration of vitamin C. In terminal cancer patients, the quality of life is as important as cure. Although there is still controversy regarding anticancer effects of vitamin C, the use of vitamin C is considered a safe and effective therapy to improve the quality of life of terminal cancer patients.