Effects of Anthocyanin Extracts from Bilberry (Vaccinium myrtillus L.) and Purple Potato (Solanum tuberosum L. var. ‘Synkeä Sakari’) on the Plasma Metabolomic Profile of Zucker Diabetic Fatty Rats

Abstract

This study compared the effects of the nonacylated and acylated anthocyanin-rich extracts on plasma metabolic profiles of Zucker diabetic fatty rats. The rats were fed with the nonacylated anthocyanin extract from bilberries (NAAB) or the acylated anthocyanin extract from purple potatoes (AAPP) at daily doses of 25 and 50 mg/kg body weight for 8 weeks. 1 H NMR metabolomics was used to study the changes in plasma metabolites. A reduced fasting plasma glucose level was seen in all anthocyanin-fed groups, especially in the groups fed with NAAB. Both NAAB and AAPP decreased the levels of branched-chain amino acids and improved lipid profiles. AAPP increased the glutamine/glutamate ratio and decreased the levels of glycerol and metabolites involved in glycolysis, suggesting improved insulin sensitivity, gluconeogenesis, and glycolysis. AAPP decreased the hepatic TBC1D1 and G6PC messenger RNA level, suggesting regulation of gluconeogenesis and lipogenesis. This study indicated that AAPP and NAAB affected the plasma metabolic profile of diabetic rats differently.

1H NMR Metabolomics and Full-Length RNA-Seq Reveal Effects of Acylated and Nonacylated Anthocyanins on Hepatic Metabolites and Gene Expression in Zucker Diabetic Fatty Rats

“…Nonacylated anthocyanins were extracted from bilberry ( Vaccinium myrtillus L.) and acylated anthocyanins from purple potato ( Solanum tuberosum L.) of the cultivar “Synkeä Sakari”. Detailed methods on the extraction, identification, and compositional analysis of anthocyanins were described in our previous study, 8 anthocyanins in bilberry were only found nonacylated, whereas 98.97% of anthocyanins in purple potato were acylated. 8 …”

“…Detailed methods on the extraction, identification, and compositional analysis of anthocyanins were described in our previous study, 8 anthocyanins in bilberry were only found nonacylated, whereas 98.97% of anthocyanins in purple potato were acylated. 8 …”

“…Rat housing and group designation were described in a previous study. 8 Briefly, 40 ZDF rats ( fa / fa ) were divided into five groups: ZDF rats fed with high-fat Purina #5008 diet as the diabetic model group (M); ZDF rats fed with Purina #5008 diet and gavaged with a low dose of nonacylated anthocyanin from bilberry (25 mg/kg body weight/day, L-NAAB); ZDF rats fed with Purina #5008 diet and gavaged with a low dose of acylated anthocyanin from potato (25 mg/kg body weight/day, L-AAPP); ZDF rats fed with Purina #5008 diet and gavaged with a high dose of nonacylated anthocyanin from bilberry (50 mg/kg body weight/day, H-NAAB); ZDF rats fed with Purina #5008 diet and gavaged with a high dose of acylated anthocyanin from potato (50 mg/kg body weight/day, H-AAPP). Sixteen of the lean Zucker rats ( fa / + ) were divided into two groups, one fed with normal diet (ND) and the other with Purina #5008 diet (Con).…”

“…The compositions of the normal diet and the Purina #5008 diet were listed in our previous study. 8 Each group contained 8 rats. The dosages of anthocyanin extracts were determined based on previous animal 16 and human 17 studies.…”

“…In our previous study using an NMR-metabolomics method, nonacylated and acylated anthocyanins displayed a different beneficial effect on the plasma metabolic profile of ZDF rats. 8 The liver plays a crucial role in the pathogenesis of T2D by regulating glucose metabolism and metabolic homeostasis. 9 We hypothesize that the anthocyanins regulate the hepatic metabolic profile by regulating the expression of the genes involved in energy metabolism in the liver; these changes can be revealed most efficiently by the powerful combination of high throughput methods of metabolomics and transcriptomics.…”