Visfatin is associated with lipid metabolic abnormalities in Lyon hypertensive rats

Abstract

1. Visfatin (also known as nicotinamide phosphoribosyltransferase or Nampt) is a novel adipokine associated with metabolic abnormalities in obesity and diabetes. The aim of the present study was to determine whether visfatin levels in the circulation and visfatin expression in fat tissues are altered in Lyon hypertensive (LH) rats, a hypertensive strain with numerous metabolic abnormalities, and, if so, to explore the possible correlations between blood visfatin levels and the metabolic abnormalities in LH rats. 2. Male 18-20-week-old LH rats and their control, Lyon normotensive (LN) rats, were used. Blood pressure was recorded in conscious, unrestrained rats. Fat tissue weight was determined. Serum visfatin concentrations were determined by enzyme immunoassay, whereas visfatin expression in fat tissues was determined by western blotting. Relationships between two parameters were evaluated by linear regression analysis. 3. The LH rats had significantly higher bodyweight and fat tissue weight compared with LN rats. Serum lipid levels of total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C) and triglyceride (TG) were all significantly higher in LH rats than in LN rats. Moreover, serum visfatin levels were higher in LH rats than in LN rats and were positively correlated with bodyweight, fat tissue weight and serum lipid levels (i.e. TC, HDL-C, LDL-C, TG and the TG:HDL-C ratio). There were no significant differences in serum glucose and insulin concentrations, or in the whole-body insulin resistance index, between LN and LH rats, and serum visfatin levels were not correlated with any of these parameters. Visfatin expression in visceral fat tissue, but not in subcutaneous fat tissue, was markedly upregulated in LH compared with LN rats. 4. In conclusion, the results of the present study demonstrate that serum visfatin levels in LH rats are elevated and are associated with lipid metabolic abnormalities.

Circulating and local visfatin/Nampt/PBEF levels in spontaneously hypertensive rats, stroke-prone spontaneously hypertensive rats and Wistar-Kyoto rats

“…1 and 2). Different from previous results was that serum visfatin levels were elevated and associated with lipids abnormalities in LH rats [15], but we did not observe similar results in SHR and SHR-SP in this study. Furthermore, a downward trend of visfatin serum levels was observed in lean hypertensive rats (Fig.…”

“…Serum visfatin levels and local visfatin expression were determined by visfatin (C-terminal) enzyme immunoassay (EIA) kit (Phoenix, Belmont, CA, USA) and western blotting analysis, respectively, as described previously [15]. The EIA kit has an intraassay CV% of \5%, an interassay CV% of \12% and a sensitivity of 0.1 ng/ml.…”

“…Tissue samples and serum biochemical assays Tissue samples and serum biochemical assays were performed as described previously [15]. Importantly, to avoid the potential influence of the intervention of measuring blood pressure on the blood visfatin level, another three subsets of these strains were used.…”

“…In a small sample in clinical research, Dogru et al [14] have shown that there was no change of blood visfatin levels in a specifically selected group of young hypertensive patients without obesity or lipid and glucose metabolic abnormalities. Additionally, in a very recent study, we have reported that serum visfatin was increased and associated with lipid metabolic abnormality in Lyon hypertensive (LH) rats [15].…”

Adipokines in inflammation, insulin resistance and cardiovascular disease

“…In a recent study, we demonstrated that visfatin, a PVAT‐derived growth factor for vascular smooth muscle cells (VSMC), is highly expressed in PVAT compared with subcutaneous and visceral fat 75 . We also provided evidence that visfatin is involved in cardio‐ and cerebrovascular disease 76–79 . Other studies have shown that visfatin induces inducible nitric oxide synthase and elicits sustained activation of extracellular signal‐regulated kinase (ERK) 1/2 signalling with the induction of NF‐κB in VSMC 80 .…”