Stachydrine ameliorates high-glucose induced endothelial cell senescence and SIRT1 downregulation

Abstract

Hyperglycaemia, a characteristic feature of diabetes mellitus, induces endothelial dysfunction and vascular complications by accelerating endothelial cell (EC) senescence and limiting the proliferative potential of these cells. Here we aimed to investigate the effect of stachydrine, a proline betaine present in considerable quantities in juices from fruits of the Citrus genus, on EC under high-glucose stimulation, and its underlying mechanism. The senescence model of EC was set up by treating cells with high-glucose (30 mM) for different times. Dose-dependent (0.001-1 mM) evaluation of cell viability revealed that stachydrine does not affect cell proliferation with a similar trend up to 72 h. Noticeable, stachydrine (0.1 mM) significantly attenuated the high-glucose induced EC growth arrest and senescence. Indeed, co-treatment with high-glucose and stachydrine for 48 h kept the percentage of EC in the G0 /G1 cell cycle phase near to control values and significantly reduced cell senescence. Western blot analysis and confocal-laser scanning microscopy revealed that stachydrine also blocked the high-glucose induced upregulation of p16(INK4A) and downregulation of SIRT1 expression and enzyme activity. Taken together, results here presented are the first evidence that stachydrine, a naturally occurring compound abundant in citrus fruit juices, inhibits the deleterious effect of high-glucose on EC and acts through the modulation of SIRT1 pathway. These results may open new prospective in the identification of stachydrine as an important component of healthier eating patterns in prevention of cardiovascular diseases.

Gaba-betaine modulates SIRT1 and p16INK4A expression during high-glucose induced endothelial cell senescence

“…Evidence, here provided, that the in vitro endothelial beneficial effect of GabaBet against the hGluc detrimental effects occurs through the positive regulation of SIRT1 and negative modulation of p16 INK4A indicate that this betaine display effects similar to those elicited by stachydrine, 18,29 suggesting its potential role as natural bioactive compound in the prevention of hyperglycaemia-induced endothelial dysfunction. A deeper characterization of the metabolism and the molecular mechanism(s) of action of this betaine is critical to understand the differences with GabaBet intermediate in gut microbial metabolism of Lcarnitine to TMAO.…”

“…GabaBet (SigmaAldrich, Milan, Italy) (up to 1 mM) was added before starting the short-term treatment with hGluc (30 mM) in complete culture medium (GabaBet+hGluc), according to previous studies on stachydrine. 18 The effect of GabaBet itself was evaluated by treating EC with GabaBet alone (GabaBet) in medium containing normal glucose (5.5 mM). Control cells (Ctr) were incubated only with normal glucose.…”

“…The highest efficiency in reducing the hGluc effects occurred at 0.1 and 1mM concentration (P<0.05 vs hGluc) ( Figure 2B). Based on these results and for a better comparison with stachydrine 18 , the GabaBet concentration of 0.1 mM was chosen for this study and, therefore, tested at different times of hGluc exposure. Results indicated that administration of GabaBet (0.1 mM) 12 h before hGluc treatment (GabaBet+hGluc) reversed the effect of hGluc on EC viability with a highest effect occurring at 48 h (P<0.05 vs hGluc treated cells) ( Figure 2C).…”

“…16 Moreover, stachydrine, the betaine of proline very abundant in citrus juice, which differs from GabaBet for its cyclic structure, 17 has been demonstrated to counteract the hGluc induced endothelial cell senescence via SIRT1 downregulation. 18 Another betaine, the 2-mercapto histidine betaine (ESH), namely ergothioneine, also protects EC against the hGluc induced endothelial senescence via the regulation of SIRT1/SIRT6 expression and their cellular targets, NF-κB and p66…”

Comparative Chemomapping of Phytoconstituents from Different Extracts of Globe Artichoke - Cynara Scolymus L.

“…The presence of trigonelline in plant extracts like coffee and fenugreek was demonstrated, and some experimental data did indicate its Nrf2 inhibitory effect together with the blocking of Nrf2-dependent expression of proteasomal genes, and reduced proteasome activity in some pancreatic carcinoma cell lines [28]. Stachydrine is a prolinebetaine type of alkaloid that was suggested to play an important role in prevention of cardiovascular diseases by inhibiting the deleterious effect of high-glucose on endothelial cells through the modulation of SIRT1 pathway [29].…”