Effect of apple polyphenols on vascular oxidative stress and endothelium function: a translational study

The purpose of the OsTea translational study was to assess the efficacy of teas (tulsi, rooibos, oolong) compared to placebo (coriander) on markers of bone health and quality of life (QOL) in those with osteopenia and on human mesenchymal stem cell (hMSC) differentiation into osteoblasts to identify potential mechanisms of action. Following consumption of tea (3 times/day; 90 days), participants collected a urine sample during the night (10pm-6am) and filled in questionnaires before and after the study. Rooibos consumption demonstrated a significant decrease in urinary CTX levels vs placebo; trended towards increases in nocturnal melatonin levels (p=0.06); significantly decreased serotonin-producing microbes in the gut; and demonstrated trends towards improvements (p=0.09) in QUALIOST emotional parameters. Tulsi consumption primarily affected subjective measures, such as significantly improved scores for PSS, STAI-trait anxiety, and osteoporosis/osteopenia-related parameters in the QUALIOST. To further identify potential mechanisms underlying these actions of rooibos on CTX and melatonin (urinary and gut), rooibos and melatonin effects on human osteoblastogenesis were carried out for 21 days under oxidative stress conditions to mimic osteopenia. Although both rooibos and melatonin protected against oxidative stress-induced loss of osteoblasts in vitro, their underlying mechanisms were different. Melatonin, like tulsi and oolong, demonstrated the greatest protection against oxidative stress at days 10-11 of exposure, which was due to effects on hMSC viability and through melatonin receptors. Rooibos, on the other hand, demonstrated protection at days 10-11 and 20-21, which was through signaling mechanisms involved in differentiation processes and not on cell viability. These findings suggest that the clinical actions of rooibos on decreasing CTX levels in a population with osteopenia may be through a cooperative effort between melatonin and rooibos by protecting hMSC viability against oxidative stress-induced loss and by promoting osteoblast differentiation, respectively. This study also supports the use of tulsi for improving quality of life in a population susceptible to osteoporosis.

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Abstract 125: Hyperacetylation of CypD Contributes to Mitochondrial Dysfunction, Vascular Oxidative Stress and Hypertension, and Mitochondria-Targeted Isoketal Scavenger mito2HOBA Prevents CypD Hyperacetylation and Reduces Hypertension

Hypertension ◽

10.1161/hyp.72.suppl_1.125 ◽

2018 ◽

Vol 72 (Suppl_1) ◽

Cited By ~ 1

Author(s):

Sergey I Dikalov ◽

Vladimir Mayorov ◽

Arvind Pandey ◽

Alexander Panov ◽

Hana Itani ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Vascular Oxidative Stress

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Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents

International Journal of Molecular Sciences ◽

10.3390/ijms20030499 ◽

2019 ◽

Vol 20 (3) ◽

pp. 499 ◽

Cited By ~ 6

Author(s):

Michela Zanetti ◽

Gianluca Gortan Cappellari ◽

Andrea Graziani ◽

Rocco Barazzoni

Keyword(s):

Oxidative Stress ◽

Lipid Accumulation ◽

High Fat Diet ◽

Vascular Function ◽

Vascular Dysfunction ◽

High Fat ◽

Enos Expression ◽

Unacylated Ghrelin ◽

Vascular Oxidative Stress ◽

Expression And Activity

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.

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