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BMC PharmacologyBMC Pharmacology 2002,BioMed CentralResearch articlexOpen AccessThe enhancement of the
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BMC PharmacologyBMC Pharmacology 2002,BioMed CentralResearch articlexOpen AccessThe enhancement of the hyperglycemic effect of S-nitrosoglutathione and S-nitroso-N-acetylpenicillamine by vitamin C in an animal modelDonovan McGrowder, Dalip Ragoobirsingh* and Tara DasguptaAddress: Department of Basic Medical Sciences (Biochemistry Section) and Department of Chemistry, University of The West Indies, Mona, Kingston 7, Jamaica, West Indies E-mail: Donovan McGrowder – [email protected]; Dalip Ragoobirsingh* – [email protected]; Tara Dasgupta – [email protected] *Corresponding authorPublished: 13 September 2002 BMC Pharmacology 2002, 2:18 This article is available from: http://www.biomedcentral.com/1471-2210/2/Received: 18 March 2002 Accepted: 13 September?2002 McGrowder et al; licensee BioMed Central Ltd. This article is published in Open Access: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article’s original URL.AbstractBackground: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetlypenicillamine (SNAP) are two of the most common sources of nitric oxide (NO) in the biomedical field. Vitamin C has been known to accelerate the decomposition of GSNO and SNAP increasing the release and availability of NO which is cytotoxic at non-physiological concentrations. The study investigates any potential detrimental effect of vitamin C PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/27906190 and GSNO, vitamin C and SNAP on glucose metabolism in normotensive and normoglycemic dogs. Results: The results showed that administration of vitamin C (50 mg/kg) and GSNO (35 mg/kg 50 mg/kg), or vitamin C (50 mg/kg) and SNAP (10 mg/kg) to overnight fasted dogs resulted in significant elevation of the blood glucose levels, attaining maximum level at the 2.0 or 2.5 h time point postprandially. The elevated blood glucose levels were due to significant reduction in plasma Mitochondrial division inhibitor 1 supplier insulin levels in the dogs treated with vitamin C and GSNO, or vitamin C and SNAP (P < 0.05). The decreased insulin response was associated with significant elevation of nitric oxide produced from GSNO and SNAP co-administered with vitamin C, as assessed by plasma nitrate/nitrite levels. Conclusions: The results indicate that enhanced NO release by vitamin C affects postprandial blood glucose and plasma insulin levels and the reduced glucose tolerance is mainly due to impaired insulin release. The clinical relevance of the findings of this study suggest that hypertensive diabetic patients treated with GSNO or SNAP, who are on vitamin C supplements may be more predisposed to further decrease in their glycemic control.BackgroundVitamin C (ascorbic acid) is a naturally occurring PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28154141 antioxidant in human plasma and is capable of scavenging super oxide anion [1]. Vitamin C levels in plasma and tissues have been reported to be significantly lower than normal in diabetic animals and humans, and might contribute tothe complications found at the late stages of diabetes [2]. Chronic vitamin C administration has beneficial effects upon glucose and lipid metabolism in aged non-insulin dependent (type 2) diabetic patients [3], and high-dose supplementation may have beneficial effect in type 1 diabetes [4]. However, research carried out by investigatorsPage 1 of(page number not for citation purposes)BMC Pharmacology 2002,http://www.biomedcentral.com/1471-2210/2/Blood Glucose Concentration (mmol/L)examining the adverse effects of vitamin C, discovered that elevated.