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Objective: To investigate the effect of epigallocatechin-3-gallate (EGCG) on endothelial dysfunction in spontaneously hypertensive rats (SHR). Methods: Wistar-Kyoto (WKY) rats and SHR were divided into four groups; WKY control, SHR control and SHR treated with EGCG (50 mg/kg/day) or losartan (10 mg/kg/day). The treatment was given daily for 4 weeks by oral gavage and the blood pressure was monitored by tail-cuff method every 3 days. Acetylcholineinduced endothelium-dependent relaxations were assessed in isolated phenylephrine-precontracted aortic rings at the end of treatment. The vascular levels of reactive oxygen species, nitric oxide, tetrahydrobiopterin, and cyclic guanosine monophosphate were also measured. Moreover, the expression of angiotensin II type 1 (AT1) receptor protein was determined. Results: The systolic blood pressure was significantly decreased in SHR treated with EGCG. The impaired endothelium-dependent relaxation was significantly improved in aortic ring isolated from the EGCG-treated SHR group. EGCG also significantly increased the levels of nitric oxide, tetrahydrobiopterin, and cyclic guanosine monophosphate, while decreasing the level of reactive oxygen species and the protein expression of AT1 receptor in SHR. Conclusions: EGCG attenuates endothelial dysfunction in SHR by decreasing oxidative stress and increasing vascular nitric oxide bioavailability, which may be modulated partly by inhibition of vascular AT1 receptors. An increase in endothelium-dependent relaxation may contribute to a decrease in blood pressure in hypertensive animals. [ABSTRACT FROM AUTHOR]

Peperomia pellucida (L.) Kunth has been used widely to treat headache, kidney disease, fever, and hypertension. Previous in vitro studies discovered that the flavonoid-rich extract of this plant has potential hypotensive effects, specifically angiotensin-converting enzyme (ACE)-inhibitory activity. However, there is insufficient scientific evidence to validate the result in vivo. This study investigated the dose dependencies of the effects of the ethyl acetate fraction of the ethanolic extract of this plant on blood pressure and biomarkers associated with the renin–angiotensin–aldosterone systems (RAAS), such as angiotensin II (AII) and the plasma renin concentration (PRC). In total, 30 two-kidney, one-clip (2K1C) hypertensive model rats were divided into five groups (n = 6 each): model group, captopril 25 mg/kg BW group, and three different ethyl acetate groups (25, 50, and 100 mg/kg BW). Another six rats comprised the sham group. Renal hypertensive rats (RHRs) were generated using stainless steel modification clips. Drugs were administered via oral gavage for 2 consecutive weeks. Blood pressure was measured weekly prior to treatment. Blood samples were collected before treatment and after the last dose to measure AII and PRC. The left kidney was isolated for histopathological examination. Blood pressure, AII levels, and PRC were elevated after 6 weeks in RHRs. Treatment with captopril and the ethyl acetate fraction of P. pellucida (L.) Kunth decreased blood pressure, AII levels, and PRC. The ethyl acetate fraction at a dose of 50 mg/kg BW had similar ACE-inhibitory effects as captopril. Histopathological examination disclosed coagulative necrosis in clipped kidneys. Impairment was alleviated in a dose-dependent manner by P. pellucida (L.) Kunth, similarly as observed in the captopril group. P. pellucida (L.) Kunth targets the renin–angiotensin–aldosterone system, which might explain its antihypertensive effects. [ABSTRACT FROM AUTHOR]

Ventricular remodeling is associated with many heart diseases, and ventricular remodeling induced by hypertension can be fatal independent of hypertension. In this study, we prepared a novel apitherapy formulation, designated Bao-Yuan-Ling (BYL), which contained propolis, royal jelly, and bee venom, to treat spontaneous hypertensive rats (SHRs). We then evaluated the pharmacology of BYL and the potential mechanisms through which BYL affects hypertension and ventricular remodeling. We found that BYL treatment could reduce blood pressure in SHRs. Thereafter, we found that BYL treatment reduced serum levels of angiotensin II, endothelin 1, and transforming growth factor-β and improved the myocardial structure. Moreover, the results of quantitative real-time polymerase chain reaction indicated that BYL treatment could upregulate the mRNA expression of peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ. Thus, we could conclude that BYL had hypotensive and cardioprotective effects in SHRs, potentially through improvement of myocardial energy metabolism. [ABSTRACT FROM AUTHOR]

Seafood processing by-product, skate ( Okamejei kenojei ) skin, was utilized to isolate active peptides with antihypertensive effect. Two peptides (MVGSAPGVL, 829 Da and LGPLGHQ, 720 Da) were purified from skate skin gelatin. In human endothelial cells, nitric oxide (NO) synthesis was found to be increased and eNOS phosphorylation was upregulated by the peptides. The peptides exhibited inhibitory activities on the production and expression of IL-6. Furthermore, the peptides down-regulated the expression levels of endothelin-1. The peptides inhibited the NF-κB and the phosphorylation of MAPK pathways. In addition, the activation of the PI3K/Akt pathway by the peptides was confirmed. The present study demonstrated that the purified peptides had vasorelaxant effects via endothelium-dependent NO signaling through activation of the PI3K/Akt-eNOS pathway and inhibition of the NF-κB and MAPK pathways. The purified peptides could be used in the food industry as functional ingredients with potent benefits in reducing the risk of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chlorogenic acid (CGA) is key component of Eucommia ulmoides in antihypertension. • CGA and E. ulmoides extracts had advantages in organ protection. • CGA and E. ulmoides extracts create a in vivo balance for inflammation level. • The antihypertensive effect of CGA was bioavailability limited. The antihypertensive effects of Eucommia ulmoides were determined between normal rats and spontaneously hypertensive rats daily gavaged with leaf extracts, bark extract, chlorogenic acid (CGA), and captopril. Significant composition difference between leaf and bark extracts were noted since CGA was only detected in leaf extract. The overall antihypertensive effects ranked as captopril > CGA > leaf extracts > bark extract, indicating the antihypertensive effect of E. ulmoides extract was CGA-dependent. The hypertension related targets of CGA were screened out and ten KEGG pathways of these targets were significantly enriched, indicating CGA took function in antihypertension via multiple biological processes. Molecular docking revealed CGA bound more tightly to hypertension related targets than captopril, indicating CGA positively participated in antihypertension. However, drug-likeness evaluation displayed the bioavailability of CGA was 5 times lower than captopril, which was consistent with dosage difference in animal experimental. Hence, the antihypertensive effect of CGA was bioavailability limited. [ABSTRACT FROM AUTHOR]

Abstract: A practical antihypertensive food, neo-fermented buckwheat sprouts (neo-FBS), was produced from buckwheat sprouts by lactic fermentation. The neo-FBS preparation gave a 12.7 times better yield and had a 10 times more potent blood-pressure-lowering (BPL) effect than conventionally prepared products. Neo-FBS decreased both systolic and diastolic blood pressure in spontaneously hypertensive rats (SHRs) at a dose of 0.010mg/kg, an effect comparable to 1.0mg/kg captopril, an anti-hypertensive drug. Orally administered neo-FBS (10mg/kg) significantly decreased angiotensin I-converting enzyme (ACE) activity in the lung, thoracic aorta, heart, kidney, and liver of SHRs. Neo-FBS had a detectable relaxing effect on a phenylephrine-precontracted thoracic aorta in SHRs at 0.5μg/mL and the EC50 value was 8.3±1.4μg/mL. The ACE inhibition and vasorelaxation activities were found to be responsible for the excellent BPL effect of neo-FBS. As SHR is a standard model for human hypertension, neo-FBS may also have BPL effects in human patients. [Copyright &y& Elsevier]

The article discusses the outcomes of dietary oyster infusion on lipid metabolism, blood pressure, and blood glucose in Sprague-Dawley (SD) rats, hypertensive rats, and diabetic rats. The results proposes that oyster stimulates triglyceride-lowering activity in the liver through a reduction in hepatic lipogenesis in SD rats, and that it maintains the antihypertensive effect in spontaneously hypertensive rats.

Grifola frondosa (Maitake) is a culinary-medicinal mushroom found in some parts of Europe, North America, and Asia. It usually grows naturally on and around the roots of various kinds of deciduous trees. In Japan, it was found in the northern part, and wild G. grondasa was served only at top-class restaurants because of its good flavor, crisp texture, and excellent aroma. Since the mid-1980s, the development of successful cultivation methods has led to its availability in large-scale production and extensive research. The main research on G. frondosa has been conducted in antitumor, anti-HIV, antihypertension, antidiabetes, antihyperlipemia, and antiobesity, and the results demonstrated that G. grondosa is one of the most bioactive, safe mushrooms. In this article, the artificial cultivation and the physicochemical and pharmacological properties of G. frondosa are described in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oral administration of RBPs reduced blood pressures in SHRs. • RBPs improved the injuries of kidney, blood vessel and heart in SHRs. • RBPs improved hypertension by inhibiting RAS signaling pathway excessive activation. • RBPs improved hypertension by maintaining ET-1 / NO secretion balance. • RBPs improved intestinal flora disorder in SHRs. In our previous study, the clams (Ruditapes philippinarum) were inoculated with Bacillus natto and fermented to produce peptides (RBPs) with high ACE inhibitory effect in vitro. In this study, we continued to explore the anti-hypertensive effect and potential mechanisms of RBPs in vivo. The results showed that RBPs significantly reduced both systolic and diastolic blood pressure and alleviated the damage of kidney, thoracic aorta and heart of spontaneously hypertensive rats after 8 weeks of treatment. Meanwhile, RBPs could also inhibit the expression of RAS signaling pathway, maintained the secretion balance of NO/ET-1 in vascular endothelial cells and inhibited the cardiac TGF-β/Smad pathway. Most notably, RBPs could also improve the gut microbiota by decreasing the ratio of Firmicutes and Bacteroidetes and increasing the relative abundance of certain genera, like Ruminococcaceae_UCG-014. The data suggested that RBPs could be used as functional food ingredient for the improvement of hypertension. [ABSTRACT FROM AUTHOR]

• The main components of camellia oil were oleic acid and linoleic acid. • Camellia oil markedly reduced systolic blood pressure of SHRs. • Camellia oil significantly reduced ACE activities in local tissues. • Camellia oil modulated the balance of vasoconstrictor and relaxing factors. The purpose of this study was to investigate the antihypertensive effect of camellia oil in vivo and its potential ACE-pathway mechanism. The results showed that the contents of oleic acid and linoleic acid in camellia oil were 78.83% and 8.32%, respectively. In vivo experimental results exhibited that both low-dose and high-dose groups significantly reduced the systolic blood pressure (SBP) in acute and long-term administration experiments compared to the control group. Camellia oil with various dosages significantly reduced the angiotensin-converting enzyme (ACE) activities of tissues and the levels of endothelin, renin and angiotensin II in serum. Moreover, camellia oil performed a similar reduction level on SBP of spontaneously hypertension rats (SHRs) for both captopril and olive oil. Overall, camellia oil exert antihypertension effect by modulating the balance of endothelium-derived vasoconstrictor and relaxing factors in serum. [ABSTRACT FROM AUTHOR]