Effects of sesamin on altered vascular reactivity in aortic rings of deoxycorticosterone acetate-salt-induced hypertensive rat

Effects of sesame (Sesamum indicum L.) and bioactive compounds (sesamin and sesamolin) on inflammation and atherosclerosis: A review

Inflammation, oxidative stress, obesity, infection, hyperlipidemia, hypertension, and diabetes are the main causes of atherosclerosis, which in the long term lead to hardening of the arteries. In the current study, we reviewed recent findings of the mechanism of sesame and its active compounds of sesamin and sesamolin regulates on atherosclerosis. Sesame can decrease the lipid peroxidation and affect the enzymes, which control the balance of oxidative status in the body. Besides modulating the inflammatory cytokines, sesame regulates the main mediators of the signaling pathways in the process of inflammation, such as prostaglandin E2 (PGE2), nuclear factor kappa light-chain enhancer of activated B cells (NF-kB) and peroxisome proliferator-activated receptor gamma (PPAR-γ). Sesame decreases the growth of different pathogens. It fights against obesity and helps to reduce weight, body mass index (BMI), waist circumference, and lipid count of serum and liver. In addition to lowering fasting blood sugar (FBS), it decreases the hemoglobin A1c (HbA1c) and glucose levels and improves insulin function. With high content of linoleic acid, α-linolenic acid, and total polyunsaturated fatty acid (PUFA), sesame efficiently controls the blood plasma lipids and changes the lipid profile. In the case of hypertension, it maintains the health of endothelium through multiple mechanisms and conserves the response of the arteries to vasodilation. PUFA in sesame suppresses blood clotting and fibrinogen activity. All the mentioned properties combat atherosclerosis and hardening of blood vessels, which are detailed in the present review for sesame.

Evaluation of wiping edible sesame oils in the oral cavities of hospitalised older patients who resist oral hygiene management

Context

One of the causes of aspiration pneumonia is poor oral hygiene. We need care methods that caregivers can quickly, safely and inexpensively implement for convalescents with inadequate self-care. Edible sesame oil containing sesamin or sesaminol has already been shown to inhibit bacterial and fungal growth and have a vasodilating effect.

Aims

The aim of this study is to evaluate the usefulness of using edible sesame oils for oral hygiene management.

Settings and Design

This study evaluates an oral hygiene management method using two types of sesame oils in elderly hospitalised patients resistant to oral hygiene management.

Methods and Material

The inpatients received oral care for 90 days. In the intervention groups, nurses brushed and wiped the oral cavity with roasted sesame oil (RSO) or sesame salad oil, while in the control group, care with tap water alone and brushing were done. Bacteria and Candida counts from tongue swabs, water content from the tongue's surface and cheek mucosa, oral health assessment tool (OHAT) and cytology of the cheek mucosa were assessed every 30 days before and after the intervention.

Results

RSO showed a tendency to reduce the number of bacteria and Candida. There was an improvement in the OHAT scores with both oils. The water content or cytology was not changing.

Conclusions

Sesame oils may improve oral hygiene and maintain health in older patients.

A Comprehensive Review on Distribution, Pharmacological Properties, and Mechanisms of Action of Sesamin

Sesamin is a kind of fat-soluble lignan extracted from sesame seeds or other plants. It has attracted more and more attention because of its extensive pharmacological activities. In this study, we systematically summarized the pharmacological activities of sesamin including antioxidant, anti-inflammatory, anticancer, protection of liver and kidney, prevention of diabetes, hypertension, and atherosclerosis. Studies focus on the abilities of sesamin to attenuate oxidative stress by reducing the levels of ROS and MDA, to inhibit the release of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, etc.), and to induce apoptosis and autophagy in cancer cells through a variety of signaling pathways such as NF-κB, JNK, p38 MAPK, PI3K/AKT, caspase-3, and p53. By inhibiting the production of ROS, sesamin can also enhance the biological activities of NO in blood vessels, improve endothelial dysfunction and hypertension, and change the process of atherosclerotic lesion formation. In line with this, the various pharmacological properties of sesamin have been discussed in this review so that we can have a deeper understanding of the pharmacological activities of sesamin and clear the future development direction of sesamin.

Health benefits of sesamin on cardiovascular disease and its associated risk factors

Sesamin, a major lignin isolated from sesame (Sesamum indicum) seeds and sesame oil, is known to possess antioxidant and anti-inflammatory properties. Several studies have revealed that oxidative stress and inflammation play a major role in a variety of cardiovascular diseases (CVDs). This comprehensive review summarizes the evidence on the effects of sesamin on CVD and its risk factors, principally due to its antioxidant properties. Specifically, this review highlights the mechanisms underlying the anti-hypertensive, anti-atherogenic, anti-thrombotic, anti-diabetic, and anti-obesity, lipolytic effects of sesamin both in vivo and in vitro, and identifies the signaling pathways targeted by sesamin and its metabolites. The data indicates that RAS/MAPK, PI3K/AKT, ERK1/2, p38, p53, IL-6, TNFα, and NF-κB signaling networks are all involved in moderating the various effects of sesamin on CVD and its risk factors. In conclusion, the experimental evidence suggesting that sesamin can reduce CVD risk is convincing. Thus, sesamin can be potentially useful as an adjuvant therapeutic agent to combat CVD and its multitude of risk factors.

Dietary lignans: physiology and potential for cardiovascular disease risk reduction

The present review of the literature on lignan physiology and lignan intervention and epidemiological studies was conducted to determine if lignans decrease the risks of cardiovascular disease in Western populations. Five intervention studies using flaxseed lignan supplements indicated beneficial associations with C-reactive protein, and a meta-analysis that included these studies also suggested lignans have a lowering effect on plasma total and low-density lipoprotein cholesterol. Three intervention studies using sesamin supplements indicated possible lipid- and blood pressure-lowering associations. Eleven human observational epidemiological studies examined dietary intakes of lignans in relation to cardiovascular disease risk. Five showed decreased risk with either increasing dietary intakes of lignans or increased levels of serum enterolactone (an enterolignan used as a biomarker of lignan intake), five studies were of borderline significance, and one was null. The associations between lignans and decreased risk of cardiovascular disease are promising, but they are yet not well established, perhaps due to low lignan intakes in habitual Western diets. At the higher doses used in intervention studies, associations were more evident.

Nitric oxide pathway-mediated relaxant effect of aqueous sesame leaves extract (Sesamum radiatum Schum. & Thonn.) in the guinea-pig isolated aorta smooth muscle

Background

Sesamum radiatum Schum. & Thonn. (Pedaliaceae) is an annual herbaceous plant, which belongs to the family Pedaliaceae and genus Sesamum. Sesame is used in traditional medicine in Africa and Asia for many diseases treatment. Sesame plant especially the leaves, seed and oil are consumed locally as a staple food by subsistence farmers. The study analyses the relaxation induced by the aqueous extract of leaves from sesame (ESera), compared with those of acetylcholine (ACh) in the guinea-pig aortic preparations (GPAPs), in order to confirm the use in traditional medicine for cardiovascular diseases.

Methods

The longitudinal strips of aorta of animals were rapidly removed from animals. The aorta was immediately placed in a Mac Ewen solution. Experiments were performed in preparations with intact endothelium as well as in aortae where the endothelium had been removed. The preparations were suspended between two L-shaped stainless steel hooks in a 10 ml organ bath with Mac Ewen solution. The isometric contractile force of the aorta strips of guinea-pig were recorded by using a strain gauge. All both drugs caused concentration-dependent relaxations responses.

Results

The aqueous extract of leaves from sesame ESera (1 × 10^-7 – 0.1 μg/ml) caused a graded relaxation in GPAPs with intact endothelium, with a EC₅₀-value of 1 × 10^-4 μg/ml. The same effect was observed with ACh (7 × 10^-2 nM – 7 × 10^-1 μM), which caused relaxation in a concentration-dependent manner. The relaxation in response to ESera and, like that to ACh in GPAPs without endothelium, was fully abolished. Destruction of the endothelium or incubation with the nitric oxyde synthase inhibitor (L-NNA) significantly enhanced the inhibition of the relaxation response to ESera. Moreover, all concentrations induced vasoconstrictions. However, L-NNA produced a significant displacement to the right (about 65-fold) of the relaxation response to ESera. Similar results were obtained with ACh. Both diclofenac and tetra-ethyl-ammonium (TEA) pretreatment of GPAPs induced a suppression of the relaxation caused by ESera, and produced a very significant rightward shifts of the CRC (16-fold) for diclofenac and increase the Emax. In contract, the relaxation caused by ACh was not significantly affected by diclofenac or by TEA.

Conclusion

Thus, the present results indicate clearly that the nitric oxide largely contribute to the relaxation effect of Esera and of ACh in GPAPs. In addition, their contractile effects are also mediated by cyclooxygenase activation, and probably the K+ channels involvement, that confirm the use of various preparations of Esera for the treatments of cardiovascular diseases.

Sesamol induces nitric oxide release from human umbilical vein endothelial cells

Sesamol, which is derived from sesame seed lignans, is reportedly an antioxidant. Nitric oxide (NO), the most important vascular relaxing factor, is regulated in the endothelium. In addition, NO is involved in protecting endothelium and has antiatherosclerotic and antithrombotic activities. The endothelium produces NO through the regulation of both endothelial NO synthase (eNOS) expression and activity in endothelial cells. This study sought to investigate the effect of sesamol on NO released from human umbilical vein endothelial cells (HUVEC) and to examine the expression and activity of eNOS. Sesamol induced NO release from endothelial cells in a dose-dependent manner (from 1 to 10 microM), as measured 24 h after treatment; the expression of the eNOS gene at both transcription and translation levels; and NOS activity in endothelial cells. The content of cGMP was also increased by sesamol through NO signaling. The transcription of eNOS induced by sesamol was confirmed through the activation of PI-3 kinase-Akt (protein kinase B) signaling. The results demonstrate that sesamol induces NOS signaling pathways in HUVEC and suggest a role for sesamol in cardiovascular reactivity in vivo.

Sesamin induces nitric oxide and decreases endothelin-1 production in HUVECs: possible implications for its antihypertensive effect

OBJECTIVE

Sesamin has been proved to be antihypertensive. Nitric oxide (NO) is the most important vascular relaxing factor that is regulated in endothelium. Endothelin-1 (ET-1) is characterized as a potent vasoconstrictor and is also regulated in endothelium. Alterations in the endothelial production of NO and ET-1 are known to correlate with hypertension. This study investigated the effect of sesamin on NO and ET-1 in the human umbilical vein endothelial cells (HUVECs).

DESIGN

The concentrations of NO and ET-1 in the medium of HUVECs treated by sesamin were measured. The mRNA and protein expressions of nitric oxide synthase (NOS), endothelin converting enzyme-1 (ECE-1), and endothelin-1 (ET-1) were also investigated. Other than the mRNA and protein expression, NOS activity and cyclic GMP (cGMP) were detected.

METHODS

The NO concentration was detected by colorimetric assay. The cGMP and ET-1 were analyzed by EIA. The eNOS, ECE-1, and ET-1 mRNA expressions were assayed by Northern blot. The eNOS and ECE-1 protein expressions were analyzed by Western blot. The NOS activity was assayed by detecting the level of [H]-1-citrullin transformed from [H]-1-arginine.

RESULTS

Sesamin not only increased the NO concentration in the medium of HUVECs in a dose-dependent manner after 24 h, but also induced eNOS mRNA and protein expressions. NOS activity in the HUVECs was also induced by sesamin. The content of cGMP was induced by sesamin through NO signaling. On the other hand, the ET-1 concentration in the medium of HUVECs treated by sesamin was suppressed in a dose-dependent manner after 24 h. The ECE-1 protein and mRNA expressions were also inhibited by sesamin. However, the mRNA expression of prepro ET-1 was not influenced by sesamin.

CONCLUSION

From the above results, it is suggested that sesamin may improve hypertension by its ability to induce NO and inhibit ET-1 production from endothelial cells. The increase of NO by sesamin is through the induction of eNOS gene expression. The decrease of ET-1 by sesamin is through the inhibition of ECE gene expression, but is not through the inhibition of prepro ET-1 gene expression.

Dietary phytoestrogens and vascular function in postmenopausal women

OBJECTIVE

To investigate the effects of low levels of intake of phytoestrogens in Western habitual diet on vascular function.

DESIGN

A cross-sectional study.

SETTING

A population-based study.

PARTICIPANTS

A total of 301 postmenopausal women aged 60-75 years living in The Netherlands. DETERMINANT: Dietary phytoestrogen intake as assessed using a food frequency questionnaire covering the year prior to enrollment.

MAIN OUTCOME MEASURES

Blood pressure, hypertension, endothelial function and ankle brachial index.

RESULTS

The median isoflavone intake was 0.2 mg in the lowest tertile and 11.4 mg in the highest tertile. Median lignan intake was 0.8 and 2.2 mg, respectively. No associations were found for higher intake of isoflavones, systolic and diastolic blood pressures, ankle-arm blood pressure index, endothelial function or hypertension. For lignans no association was found for ankle-arm blood pressure index or endothelial function, but we did observe lower systolic and diastolic blood pressures and a lower prevalence of hypertension (systolic blood pressure difference T3-T1, -11.2 mmHg, 95% confidence interval = -17.8 to -4.5, P for trend = 0.001; diastolic blood pressure difference T3-T1, -3.6 mmHg, 95% confidence interval = -7.8 to 0.6, P for trend = 0,08; and prevalence of hypertension, odds ratio T3 versus T1 = 0.41, 95% confidence interval = 0.22-0.76, P for trend over tertiles = 0.004).

CONCLUSION

The results of this study suggest a protective effect of dietary lignan intake on blood pressure and hypertension, even at low levels.

Antihypertensive effect of sesamin. IV. Inhibition of vascular superoxide production by sesamin

We previously demonstrated the preventive effect of sesamin, a lignan from sesame oil, on the development of several experimental models of hypertension. In the present study, we explored the mechanisms underlying the antihypertensive effect of sesamin using the deoxycorticosterone acetate (DOCA)-salt rat hypertensive model. After a 5-week treatment period, aortic superoxide (O2-) production was measured in the lucigenin chemiluminescence assay. Chemiluminescence signals significantly decreased in sesamin-containing diet-fed DOCA-salt hypertensive rats compared with those in the normal diet-fed DOCA-salt rats, although the signals in sham-operated control animals were not affected by the sesamin feeding. In addition, there was a positive correlation between systolic blood pressure and aortic O2- production. These findings suggest that sesamin feeding inhibits enhanced vascular O2- production in DOCA-salt hypertensive rats and that the antioxidative action of sesamin may contribute to its antihypertensive activity.

Cardiovascular properties of yangambin, a lignan isolated from Brazilian plants

Yangambin was initially selected from a number of lignans isolated from Brazilian plants for its ability to antagonize Platelet-Activating Factor (PAF, 1-O-hexadecyl-2-acetyl- sn-glyceryl-3-phosphorylcholine)-induced biological effects. Subsequently it was shown that, besides its antagonistic properties at PAF receptors, yangambin also prevents the cardiovascular collapse observed during anaphylactic and endotoxic/septic shocks, as well as the vascular and cardiac hyporesponsiveness to catecholamines in endotoxic shock. It is suggested that this naturally occurring compound could be of potential interest in the adjunctive management of the above mentioned pathologies. In the present article, we review the main studies investigating the pharmacological properties of yangambin related to the cardiovascular function.