Thiamine, a water-soluble B-complex vitamin, is an essential element for the normal functioning of heart, muscles and nervous system. Its deficiency might lead to disease conditions such as beriberi, Korsakoff syndrome, and Wernicke’s disease. Now, a recent study published in the December issue of the journal Diabetologia demonstrates that high doses of thiamine could reverse the early onset of kidney disease.
Assistant Professor Naila Rabbani and Professor Paul J Thornalley, from the Warwick Medical School, University of Warwick, UK, led the randomized double-blind placebo-controlled pilot study in collaboration with researchers at the University of Punjab and Sheikh Zayed Hospital, Lahore, Pakistan. The study was conducted on 40 patients with type 2 diabetes and microalbuminuria to assess the effect of thiamine supplementation in reversing the condition. Subjects were administered with three 100 mg capsules of thiamine or placebo, daily for three months followed by a two-month washout period. Researchers determined the change in urinary albumin excretion (UAE), concentrations of thiamine in plasma, and other markers of renal and vascular dysfunction.
The study found a significant reduction in UAE, in patients receiving thiamine with respect to baseline (median=17.7 mg/24 hours; n=20) as compared to those who received placebo. Also, UAE was lower (30.1 mg/24 hours) in thiamine treated patients compared to those who received placebo (35.5 mg/24 hours). An insignificant lowering of UAE was observed in both the groups during the two-month washout period. Glycemic control, dyslipidemia or blood pressure was not affected by the thiamine treatment. Based on the study results, the researchers suggested that high-dose supplementation of thiamine could offer better treatment for early-stage diabetic nephropathy.
In another study, Kohda and colleagues (The Journal of Toxicological Sciences, 2008) reported the effect of flux reduction through high-dose thiamine therapy-induced hexosamine biosynthesis pathway on diabetes-induced cardiac fibrosis. Streptozotocin was used to induce diabetes in rat models. The animal models were divided into four groups: untreated nondiabetic controls, untreated diabetic rats, thiamine-supplemented diabetic rats, and thiamine-supplemented nondiabetic controls, and were followed-up for two weeks.
Matrix metalloproteinase activity, morphological changes, total cholesterol and triglycerides, brain natriuretic peptide, transforming growth factor beta-1, thrombospondine, fibronectin, plasminogen activator-I and connective tissue growth factors were analyzed during the study. Oral supplementation prevented the depletion of thiamine level, enhanced pro-fibrotic mRNA level, and reduced metalloproteinase activity in the heart of diabetic rats, resulting in the prevention of diabetes-induced cardiac fibrosis, with no effect on glycemic levels. The investigators speculated that the suppression of hexosamine biosynthesis pathway, through thiamine supplementation, prevented the development of diabetes-induced cardiac fibrosis in diabetic rats.
Thiamine, also known as vitamin B1, is an indispensable component involved in glucose metabolism and should be supplied to the body through daily diet. According to the United States Renal Data System (USRDS) 2007 Annual Data Report, yearly, 44% of new cases of kidney failure occur due to diabetes, the most common cause of the condition. The National Diabetes Statistics 2007 estimates that around 24 million people in the US have diabetes, with approximately 180,000 cases of diabetes-induced kidney failure.
Oral supplementation of thiamine has been shown to improve various metabolic functions in diabetic patients. The current study, demonstrating the reversal of microalbuminuria with high-dose thiamine administration in diabetics, could be used as a novel approach in preventing early-stage renal disease.
References
1. Rabbani N, Alam SS, Riaz S, et al. High-dose thiamine therapy for patients with type 2 diabetes and microalbuminuria: a randomised, double-blind placebo-controlled pilot study. Diabetologia. 2008 Dec 5. [Epub ahead of print]
2. Kohda Y, Shirakawa H, Yamane K, et al. Prevention of incipient diabetic cardiomyopathy by high-dose thiamine. J Toxicol Sci. 2008 Oct;33(4):459-72.
