Dietary polyunsaturated fatty acid and antioxidant modulation of vascular dysfunction in the spontaneously hypertensive rat

Dietary fatty acids differentially affect secretion of pro-inflammatory cytokines in human THP-1 monocytes

Monocytes are a major population of circulating immune cells that play a crucial role in producing pro-inflammatory cytokines in the body. The actions of monocytes are known to be influenced by the combinations and concentrations of certain fatty acids (FAs) in blood and dietary fats. However, systemic comparisons of the effects of FAs on cytokine secretion by monocytes have not be performed. In this study, we compared how six saturated FAs (SFAs), two monounsaturated FAs (MUFAs), and seven polyunsaturated FAs (PUFAs) modulate human THP-1 monocyte secretion of TNF, IL-1β, and IL-6 in the absence or presence of lipopolysaccharide. SFAs generally stimulated resting THP-1 cells to secrete pro-inflammatory cytokines, with stearic acid being the most potent species. In contrast, MUFAs and PUFAs inhibited lipopolysaccharide-induced secretion of pro-inflammatory cytokines. Interestingly, the inhibitory potentials of MUFAs and PUFAs followed U-shaped (TNF and IL-1β) or inverted U-shaped (IL-6) dose-response curves. Among the MUFAs and PUFAs that were analyzed, docosahexaenoic acid (C22:6 n-3) exhibited the largest number of double bonds and was found to be the most potent anti-inflammatory compound. Together, our findings reveal that the chemical compositions and concentrations of dietary FAs are key factors in the intricate regulation of monocyte-mediated inflammation.

Picotamide inhibits a wide spectrum of agonist-induced smooth muscle contractions in porcine renal interlobar and coronary arteries

Picotamide is a thromboxane A₂ (TXA₂) receptor antagonist and TXA₂ synthase inhibitor. In clinical studies, it has been considered as a platelet aggregation inhibitor and improved renal function. In vitro studies suggested inhibition of smooth muscle contraction by picotamide, which is poorly understood. Here, we examined effects of picotamide on contractions of renal interlobar and coronary porcine arteries, induced by different vasoconstrictors. Contractions were induced in an organ bath by agonists or electric field stimulation (EFS). Picotamide inhibited EFS‐induced contractions of interlobar arteries around 50% using concentrations of 100 and 300 µM. In interlobar arteries, concentration response curves for contractions induced by three different α₁‐adrenoceptor agonists were shifted to the right by picotamide (2–10‐fold increases in EC₅₀). In coronary arteries, α₁‐adrenergic contractions were inhibited without right shift (approx. 50%). Contractions induced by two different cholinergic agonists in coronary arteries were inhibited by picotamide (≥50%) withouth right shift. Inhibition of serotonin‐induced contractions by picotamide showed features of a right shift, whereas contractions induced by the TXA₂ analog U46619, angiotensin‐II, and endothelin‐1 were inhibited by picotamide in interlobar and coronary arteries without right shifts and to different degree. Picotamide inhibits a wide spectrum of vasoconstrictor‐induced contractions in porcine interlobar and coronary arteries. Inhibition of vasocontraction may contribute to beneficial effects of picotamide in the cardiovascular system and kidney.

Different consumed oils and metabolic parameters in type 2 diabetes patients in diabetes society of Natanz

AIMS

This study, for the first time, has investigated the effect of highly consumed oils in Iran on type 2 diabetic patient's blood pressure.

MATERIALS AND METHODS

After measuring height, weight and blood pressure and calculating Body Mass Index (BMI) of 200 patients (30-65 years old) with type 2 diabetes (26.7% men, 73.3% women) in diabetes center of Natanz, their consumed oil was obtained by questionnaire, and their blood lipid and glucose were also measured. Data analyzed by SPSS 16 software, one-way ANOVA, independent T test, and Means procedure statistic tests.

RESULTS

In mean procedure test, the highest average of systolic and diastolic blood pressure was in patients consumed solid and semi-solid oils; and the lowest was in patients consumed vegetable liquid oils. However, women consumed solid vegetable oils have lower systolic and mean arterial pressures. In one-way ANOVA test, there was a significant relation between consumed oil and hemoglobin A1C (p=0.049) and diastolic blood pressure (p=0.032).

CONCLUSION

Consumption of solid and semi-solid oils, especially animal fat, cause increasing in blood pressure of diabetic type 2 patients; but consumption of olive oil, and to a lesser extent liquid vegetable oils, related to lesser increasing in their blood pressure.

Efficient Rutin and Quercetin Biosynthesis through Flavonoids-Related Gene Expression in Fagopyrum tataricum Gaertn. Hairy Root Cultures with UV-B Irradiation

Transformed hairy roots had been efficiently induced from the seedlings of Fagopyrum tataricum Gaertn. due to the infection of Agrobacterium rhizogenes. Hairy roots were able to display active elongation with high root branching in 1/2 MS medium without growth regulators. The stable introduction of rolB and aux1 genes of A. rhizogenes WT strain 15834 into F. tataricum plants was confirmed by PCR analysis. Besides, the absence of virD gene confirmed hairy root was bacteria-free. After six different media and different sources of concentration were tested, the culturing of TB7 hairy root line in 1/2 MS liquid medium supplemented with 30 g l(-1) sucrose for 20 days resulted in a maximal biomass accumulation (13.5 g l(-1) fresh weight, 1.78 g l(-1) dry weight) and rutin content (0.85 mg g(-1)). The suspension culture of hairy roots led to a 45-fold biomass increase and a 4.11-fold rutin content increase in comparison with the suspension culture of non-transformed roots. The transformation frequency was enhanced through preculturing for 2 days followed by infection for 20 min. The UV-B stress treatment of hairy roots resulted in a striking increase of rutin and quercetin production. Furthermore, the hairy root lines of TB3, TB7, and TB28 were chosen to study the specific effects of UV-B on flavonoid accumulation and flavonoid biosynthetic gene expression by qRT-PCR. This study has demonstrated that the UV-B radiation was an effective elicitor that dramatically changed in the transcript abundance of ftpAL, FtCHI, FtCHS, FtF3H, and FtFLS-1 in F. tataricum hairy roots.

Rutin and quercetin show greater efficacy than nifedipin in ameliorating hemodynamic, redox, and metabolite imbalances in sodium chloride-induced hypertensive rats

Rutin and quercetin were investigated for their effects on blood pressure and antioxidant defense system of rats fed with 8% sodium chloride-supplemented diet (high salt diet) for 6 weeks. Animals fed with high salt diet demonstrated an increase in systolic, diastolic, pulse, and mean arterial blood pressures (p < 0.05) as well as lipid peroxidation but decreases in the activities of antioxidant enzymes compared with control group. Groups post-treated with rutin and quercetin for 2 weeks showed significant reversals in the values of these indices compared with the group fed with only the high salt diet but not post-treated. The high salt diet also led to significant increase in serum glucose, urea, creatinine, triglycerides, low-density-lipoprotein, and total cholesterol concentrations. Treatment with rutin and quercetin ameliorated the effects of high salt diet on these biochemical indices. The reference standard, nifedipin was less effective than rutin and quercetin. The results of this study highlight the risk of high salt consumption on cardiovascular health and the potent antioxidant and antihypertensive property of rutin and quercetin.

Purification and identification of antihypertensive peptides from fermented buckwheat sprouts

Buckwheat (Fagopyrum esculentum) is rich in antihypertensive compounds. This study investigated the effect of lactic-fermented buckwheat sprouts (neo-FBS) on level, identification, and potency of blood pressure-lowering (BPL) compounds. A single oral dose of 1.0 mg/kg body weight buckwheat sprouts (BS) in spontaneously hypertensive rats did not show significant BPL activity, whereas neo-FBS significantly decreased blood pressure. HPLC of neo-FBS identified two peaks absent in the profile of BS. The peak exhibiting potent BPL activity was fractionated, and six peptides (DVWY, FDART, FQ, VAE, VVG, and WTFR) and tyrosine were identified by LC-MS/MS and Edman degradation. Single oral dose administration of the peptides revealed significant BPL effect of all the peptides, with the most potent being DVWY, FQ, and VVG. DVWY, VAE, and WTFR are novel. This study demonstrates that lactic fermentation of BS produces new, highly potent antihypertensive peptides and increases active compounds GABA and tyrosine already present in BS.

Kaempferol suppresses lipid accumulation in macrophages through the downregulation of cluster of differentiation 36 and the upregulation of scavenger receptor class B type I and ATP-binding cassette transporters A1 and G1

The accumulation of foam cells in atherosclerotic lesions is a hallmark of early-stage atherosclerosis. Kaempferol has been shown to inhibit oxidized low-density lipoprotein (oxLDL) uptake by macrophages; however, the underlying molecular mechanisms are not yet fully investigated. In this study, we shown that treatment with kaempferol markedly suppresses oxLDL-induced macrophage foam cell formation, which occurs due to a decrease in lipid accumulation and an increase in cholesterol efflux from THP-1-derived macrophages. Additionally, the kaempferol treatment of macrophages led to the downregulation of cluster of differentiation 36 (CD36) protein levels, the upregulation of ATP-binding cassette (ABC) transporter A1 (ABCA1), scavenger receptor class B type I (SR-BI) and ABCG1 protein levels, while no effects on scavenger receptor A (SR-A) expression were observed. Kaempferol had similar effects on the mRNA and protein expression of ABCA1, SR-BI, SR-A, CD36 and ABCG1. The reduced CD36 expression following kaempferol treatment involved the inhibition of c-Jun-activator protein-1 (AP-1) nuclear translocation. The inhibition of AP-1 using the inhibitor, SP600125, confirmed this involvement, as the AP-1 inhibition significantly augmented the kaempferol-induced reduction in CD36 expression. Accordingly, the kaempferol-mediated suppression of lipid accumulation in macrophages was also augmented by SP600125. The increased expression of ABCA1, SR-BI and ABCG1 following kaempferol treatment was accompanied by the enhanced protein expression of heme oxygenase-1 (HO-1). This increase was reversed following the knockdown of the HO-1 gene using small hairpin RNA (shRNA). Moreover, the kaempferol-mediated attenuation of lipid accumulation and the promotion of cholesterol efflux was also inhibited by HO-1 shRNA. In conclusion, the c-Jun-AP‑1-dependent downregulation of CD36 and the HO-1-dependent upregulation of ABCG1, SR-BI and ABCA1 may mediate the beneficial effects of kaempferol on foam cell formation.

19,20-EpDPE, a bioactive CYP450 metabolite of DHA monoacyglyceride, decreases Ca2+ sensitivity in human pulmonary arteries

The aim of this study was to investigate the effect of docosahexaenoic acid monoacylglyceride (MAG-DHA) on human pulmonary arterial tone. Tension measurements on pulmonary arterial tissues demonstrated that MAG-DHA reduced U-46619-induced tone, which is highly sensitive to the H-1152 inhibitor. Results also showed that MAG-DHA treatments decreased RhoA activity levels, which in turn inactivated the Rho-kinase pathway, leading to a reduction in U-46619-induced Ca2+ sensitivity of permeabilized pulmonary artery smooth muscle cells. According to the mechanical responses assessing U-46619-induced Ca2+ sensitivity in the absence or presence of 3 μM MAG-DHA, MAG-DHA plus 1 μM N-methylsulfonyl-6-(2-propargyloxyphenyl) hexanamide (MS-PPOH, a cytochrome P-450 epoxygenase inhibitor) and 300 nM 19,20-epoxydocosapentaenoic acid (a cytochrome P-450 epoxygenase-dependent DHA metabolite), our data suggest that the MAG-DHA is metabolized in a bioactive epoxymetabolite. This epoxyeicosanoid in turn decreases active tone and Ca2+ sensitivity of smooth muscles cells through an inhibition of the Rho-kinase pathway. Together, these data provide primary evidence regarding the mode of action of MAG-DHA in human pulmonary arteries and suggest that this compound may be of pharmacological interest in patients with pulmonary hypertension to generate intracellular bioactive metabolites.

n-3 PUFA prevent metabolic disturbances associated with obesity and improve endothelial function in golden Syrian hamsters fed with a high-fat diet

Glucose intolerance and dyslipidaemia are independent risk factors for endothelium dysfunction and CVD. The aim of the present study was to analyse the preventive effect of n-3 PUFA (EPA and DHA) on lipid and carbohydrate disturbances and endothelial dysfunction. Three groups of adult hamsters were studied for 20 weeks: (1) control diet (Control); (2) high-fat diet (HF); (3) high-fat diet enriched with n-3 PUFA (HFn-3) groups. The increase in body weight and fat mass in the HF compared to the Control group (P < 0.05) was not found in the HFn-3 group. Muscle TAG content was similar in the Control and HF groups, but significantly lower in the HFn-3 group (P = 0.008). Glucose tolerance was impaired in the HF compared to the Control group, but this impairment was prevented by n-3 PUFA in the HFn-3 group (P < 0.001). Plasma TAG and cholesterol were higher in the HF group compared to the Control group (P < 0.001), but lower in the HFn-3 group compared to the HF group (P < 0.001). HDL-cholesterol was lower in the HFn-3 group compared to the Control and HF groups (P < 0.0005). Hepatic secretion of TAG was lower in the HFn-3 group compared to the HF group (P < 0.005), but did not differ from the Control group. Hepatic gene expression of sterol regulatory element-binding protein-1c, diacylglycerol O-acyltransferase 2 and stearyl CoA desaturase 1 was lower in the HFn-3 group, whereas carnitine palmitoyl transferase 1 and scavenger receptor class B type 1 expression was higher (P < 0.05). In adipocytes and adipose macrophages, PPARγ and TNFα expression was higher in the HF and HFn-3 groups compared to the Control group. Endothelium relaxation was higher in the HFn-3 (P < 0.001) than in the HF and Control groups, and was correlated with glucose intolerance (P = 0.03) and cholesterol (P = 0.0003). In conclusion, n-3 PUFA prevent some metabolic disturbances induced by high-fat diet and improve endothelial function in hamsters.

Comparison of various easy-to-use procedures for extraction of phenols from apricot fruits

Phenols are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potential antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such as cancer. The objective of this study was to investigate a suitable method for determination of protocatechuic acid, 4-aminobenzoic acid, chlorogenic acid, caffeic acid, vanillin, p-coumaric acid, rutin, ferulic acid, quercetin, resveratrol and quercitrin from apricot samples. A high-performance liquid chromatograph with electrochemical and UV detectors was used. The method was optimized in respect to both the separation selectivity of individual phenolic compounds and the maximum sensitivity with the electrochemical detection. The lowest limits of detection (3 S/N) using UV detection were estimated for ferulic acid (3 µM), quercitrin (4 µM) and quercetin (4 µM). Using electrochemical detection values of 27 nM, 40 nM and 37 nM were achieved for ferulic acid, quercitrin and quercetin, respectively. It follows from the acquired results that the coulometric detection under a universal potential of 600 mV is more suitable and sensitive for polyphenols determination than UV detection at a universal wavelength of 260 nm. Subsequently, we tested the influence of solvent composition, vortexing and sonication on separation efficiency. Our results showed that a combination of water, acetone and methanol in 20:20:60 ratio was the most effective for p-aminobenzoic acid, chlorgenic acid, caffeic acid, protocatechuic acid, ferulic acid, rutin, resveratrol and quercetin, in comparison with other solvents. On the other hand, vortexing at 4 °C produced the highest yield. Moreover, we tested the contents of individual polyphenols in the apricot cultivars Mamaria, Mold and LE-1075. The major phenolic compounds were chlorgenic acid and rutin. Chlorgenic acid was found in amounts of 2,302 mg/100 g in cultivar LE-1075, 546 mg/100 g in cultivar Mamaria and 129 mg/100 g in cultivar Mold. Generally, the cultivar LE-1075 produced the highest polyphenol content values, contrary to Mold, which compared to cultivar LE-1075 was quite poor from the point of view of the phenolics content.

Effects of deep-frying oil on blood pressure and oxidative stress in spontaneously hypertensive and normotensive rats

OBJECTIVE

Ingestion of deep-frying oil has been reported to cause physiologic and histologic changes in experimental animals' tissue, increase the oxidative stress, and possibly lead to death. The purpose of this study was to investigate the effect of deep-frying oil on oxidative stress and blood pressure in spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats.

METHODS

Deep-frying oil was prepared by frying fresh soybean oil at 180 +/- 5 degrees C for 8 h each day, for 4 consecutive days. Male SHR and WKY rats were fed diets containing 15% fresh soybean oil or deep-frying oil (DO) for 10 wk.

RESULTS

Rats ingesting the DO diet had lower feed efficiency and higher relative liver and kidney weights but deep frying had no significant influence on blood pressure in WKY or SHR rats. The DO diet had no effect on plasma renin activity, aldosterone content, or tissue angiotension-I-converting enzyme activity. WKY rats fed the DO diet showed significantly increased urinary thromboxane B(2) and 8-iso-prostaglandin F(2alpha) excretion, but not urinary 6-keto-prostaglandin F(1alpha) excretion. Diets containing deep-frying oil resulted in increased plasma thiobarbituric acid-reactive substances and nitric oxide contents and decreased plasma total antioxidant capacity in SHR and WKY rats.

CONCLUSION

The ingestion of deep-frying oil seemed not to influence blood pressure or its related parameters, but altered eicosanoid metabolism and elevated oxidative stress in SHR and WKY rats.

Anti-inflammatory effects of EPA and DHA are dependent upon time and dose-response elements associated with LPS stimulation in THP-1-derived macrophages

The long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) of fish oil, eicosapentanoic (EPA) and docosahexanoic (DHA) acids are considered cardioprotective. Inflammation elicited by macrophages is increasingly recognised in the aetiology of metabolic syndrome. This study investigated the differential anti-inflammatory potential of EPA and DHA through cytokine production and nuclear factor (NF)-kappaB signalling in a human macrophage model. We investigated the dependency of LC n-3 PUFA immune-modulation on concentration and duration of lipopolysaccharide (LPS) activation. Interleukin (IL)-1beta, IL-6 and tumor necrosis factor-alpha secretion from EPA, DHA and control cells were differentially limited by LPS concentration. In all cases, there was no benefit in activating cells with >0.1 microg/ml LPS. LC n-3 PUFA decreased proinflammatory cytokines production, an effect modulated by LPS concentration. Expression of the transcription factor NF-kappaB p65 was significantly reduced in the nucleus and retained in the cytoplasm of EPA- and/or DHA-treated macrophages during 5-h activation with 0.1 microg/ml LPS. Nuclear binding of p65 was significantly reduced in EPA- and DHA-treated cells at 2-h LPS activation. Over the time course, expression of nuclear IkappaBalpha was significantly reduced, cytoplasmic NF-kappaB p50 significantly increased and cytoplasmic cleaving enzyme IkappaB inhibitor complex significantly reduced in LC n-3 PUFA-treated cells. EPA and DHA down-regulated the production of proinflammatory cytokines associated with the aetiology of metabolic syndrome, NF-kappaB transcriptional activity and upstream cytoplasmic signalling events. Immune responses are dynamic, and the present study suggests a nutrient sensitive window of LPS activation at which EPA and DHA are strongly anti-inflammatory.

Dietary n-3 polyunsaturated fatty acids and endothelium dysfunction induced by lysophosphatidylcholine in Syrian hamster aorta

This study investigated the influence of an eicosapentaenoic acid (EPA)- or a docosahexaenoic acid (DHA)-supplemented diet on the deleterious effects of lysophosphatidylcholine (LPC) on endothelium-dependent vasorelaxation of Golden Syrian hamster thoracic aorta. In a second step, LPC-modulated phospholipase A(2) (PLA(2))-derived ways of relaxation were investigated. Golden Syrian hamsters were fed for 6 weeks with a control diet or an EPA- or DHA-supplemented diet. Aortic fatty acid composition was analyzed by gas chromatography. Aortic rings were incubated for 20 minutes with LPC before constructing cumulative concentration-response curves for acetylcholine (ACh; 3 nmol/L-30 micromol/L) or sodium nitroprusside (3 nmol/L-30 micromol/L). The EPA- or DHA-supplemented diet increased n-3 polyunsaturated fatty acids in aortic fatty acids content because of the increase of EPA or DHA content, respectively, and decreased arachidonic acid aortic content. Lysophosphatidylcholine (1, 10, 15, and 20 micromol/L) induced a concentration-dependent inhibition of ACh-induced relaxation of preconstricted aortic rings in the control group, but did not influence sodium nitroprusside-induced aortic relaxation. The DHA- or EPA-supplemented diet worsened LPC (20 micromol/L) inhibitory effects on ACh-induced vasorelaxation. In the control diet group, ACh-induced relaxation was abolished by the nitric oxide synthase inhibitor (l-N(G)-nitro-arginine methyl ester; 100 micromol/L), whether LPC was added or not. The ACh-induced vasorelaxation was partially inhibited by PLA(2) inhibitors methyl arachidonyl fluorophosphonate (25 micromol/L) and arachidonyl trifluoromethyl ketone (20 micromol/L) as well as by the combination of 2 Ca(2+)-dependent potassium (K(Ca)) channel inhibitors charybdotoxin (0.1 micromol/L) plus apamin (0.3 micromol/L). In the presence of LPC (20 micromol/L), ACh-induced vasorelaxation was abolished by these inhibitors. These effects were not influenced by DHA or EPA diet. Our results suggested that EPA- or DHA-supplemented diet did not exhibit any beneficial effect against LPC-induced inhibition of endothelium-dependent aortic relaxation in Golden Syrian hamsters. These LPC effects were associated in our study not only with an inhibition of nitric oxide-dependent vasorelaxation, but also with a concomitant activation of a compensatory vasorelaxant pathway depending both on PLA(2) metabolites and on K(Ca) channel opening.

Trace element water improves the antioxidant activity of buckwheat (Fagopyrum esculentum Moench) sprouts

Buckwheat (Fagopyrum esculentum Moench) was grown in trace element water (TEW) (100, 200, 300, 400, and 500 ppm) and deionized water (DIW) to evaluate whether the beneficial effects of trace elements on the antioxidant activity could be accomplished with the supplement of TEW. At 300 ppm, TEW significantly increased the Cu, Zn, Mn, and Fe contents in buckwheat sprout but not the Se content. However, the levels of rutin, isoorientin, vitexin, and isovitexin did not differ between buckwheat sprouts grown in TEW and DIW. The ethanolic extract from buckwheat sprout grown in 300 ppm of TEW showed higher ferrous ion chelating activity and inhibitory activity toward lipid peroxidation than that grown in DIW. The extract in the TEW group also enhanced intracellular superoxide dismutase activity and lowered reactive oxygen species and superoxide anion in the human Hep G2 cell. It was concluded that TEW could increase the antioxidant activities of buckwheat sprouts.

Analysis of long-chain ω-3 fatty acid content in fish-oil supplements

BACKGROUND

Omega-3 polyunsaturated fatty acids (long-chain omega-3 PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia in several studies, which has led national and international societies to recommend an intake of 1 g/d long-chain omega-3 PUFA for anti-atherosclerotic and antiarrhythmic purposes or 2-4 g/d for a lipid lowering effect. Numerous preparations are marketed for supplementing western diet, which is low in long-chain omega-3 PUFA. Since these preparations vary in their long-chain omega-3 PUFA content, we tested nine commercially available products for their fatty acid composition.

METHODS

Nine commercially available omega-3 fatty acid supplements were analyzed using capillary gas chromatography to determine their fatty acid content.

RESULTS

The nine preparations showed huge differences, up to 63.7 +/- 1.58 mol% (P = 0.002), in their longchain omega-3 fatty acid content. Most of them failed to achieve the daily recommended dose of 1 g, even when administered at the highest dosage according to the manufacturer's recommendations. Eight of the preparations contained either equal or significantly greater amounts of long-chain omega-3 PUFA than denoted by the manufacturer; one preparation did not provide any information. The highest percentage of DHA and EPA was detected in Omacor(95.80 +/- 0.63%) and Percucor (76.8 +/- 7.109%).

CONCLUSION

Administering long-chain omega-3 fatty acid preparations may result in huge differences in terms of the actual amount ingested. It is therefore advisable to use the most standardized and purified products available.

Salt tolerance conferred by overexpression of Arabidopsis vacuolar Na(+)/H (+) antiporter gene AtNHX1 in common buckwheat (Fagopyrum esculentum)

Agriculture productivity is severely affected by soil salinity. One possible mechanism by which plants could survive salt stress is to compartmentalize sodium ions away from the cytosol. In the present work, transgenic buckwheat plants overexpressing AtNHX1, a vacuolar Na(+)/H(+) antiporter gene from Arabidopsis thaliana, were regenerated after transformation with Agrobacterium tumefaciens. These plants were able to grow, flower and accumulate more rutin in the presence of 200 mmol/l sodium chloride. Moreover, the content of important nutrients in buckwheat was not affected by the high salinity of the soil. These results demonstrated the potential value of these transgenic plants for agriculture use in saline soil.

Argan (Argania spinosa) oil lowers blood pressure and improves endothelial dysfunction in spontaneously hypertensive rats

Traditionally hand-pressed argan oil, obtained from Argania spinosa seeds, is eaten raw in south-west Morocco; its rich composition of tocopherols, MUFA and PUFA make a study of its actions on risk factors for CVD, such as hypertension, interesting. The effects of 7 weeks of treatment with argan oil (10ml/kg) on the blood pressure and endothelial function of spontaneously hypertensive rats (SHR) and normotensive Wistar–Kyoto rats were investigated. Systolic blood pressure and heart rate were measured every week by the tail-cuff method and endothelial function was assessed by carbachol (10−8 to 10−4m)-induced relaxations of aortic rings and small mesenteric arteries pre-contracted with phenylephrine. Argan-oil administration reduced the mean blood pressure of SHR after the fifth week of treatment (P<0·05) and increased (P<0·01) the endothelial responses of arteries from SHR. The NO synthase inhibitor, l-N-ω-nitroarginine (3×10−5m) revealed a greater participation of NO in the relaxant effect after the treatment. When cyclooxygenase (COX) was blocked with indomethacin (10−5m), an involvement of COX products in the endothelium-dependent response was characterized. Enzyme immunoassay of thromboxane B2 showed a significant decrease (P<0·05) in the release of thromboxane A2 in both aorta and small mesenteric artery after argan-oil treatment of SHR. Experiments in the presence of the thromboxane A2–prostaglandin H2 receptor antagonist ICI 192, 605 (10−5m) confirmed this result. Results after incubation with the antioxidants superoxide dismutase and catalase suggested that a decreased oxidative stress might contribute to explain the beneficial effects of argan-oil treatment.

Adult cardiorenal benefits from postnatal fish oil supplement in rat offspring of low-protein pregnancies

We investigated the effect of fish oil (FO) treatment on cardiorenal structure of adult offspring from low-protein pregnancies. Three month old offspring were assigned to eight groups (four male groups and four female groups, n=8 each) (NP=normal-protein diet, LP=low-protein diet): NP, LP, NP plus FO, and LP plus FO. Left ventricle and kidney were analyzed with light microscopy and stereology. The both sexes of LP offspring showed 30% lower birth weights than the respective NP offspring and high blood pressure (BP) levels in adulthood which was efficiently reduced by FO treatment. In the heart, FO treated the cardiomyocyte hypertrophy, the vascularization impairment, and decreased the cardiomyocyte loss usually observed in adult LP offspring. In the kidney, FO treated, in the male, the imbalance of the cortex-to-medulla ratio observed in both sexes of LP offspring, and reduced the glomeruli loss in the LP offspring. The positive correlation between the number of cardiomyocyte nuclei later in life and the body mass (BM) at birth was significant only in both sexes of LP offspring and this correlation disappeared in LP plus fish oil offspring. The positive correlation between the number of glomeruli later in life and the BM at birth was significant in NP male offspring and in both sexes of LP offspring. In conclusion, FO supplement, which is a rich source of n-3 fatty acids (DHA and EPA), has beneficial effects on BP control and cardiac and renal adverse remodeling usually seen in offspring of the LP pregnancies.

Spontaneously hypertensive rats left ventricular cardiomyocyte loss attenuation through different edible oils long-term intake

BACKGROUND

Dietary lipid intake type affecting spontaneously hypertensive rats (SHR) blood pressure (BP). There are no information available whether different edible lipids long-term administration does potentiality alter the usual cardiomyocyte loss in SHR or not.

METHODS

Six groups of 3-month-old male SHR received different edible oils (fish, canola, palm, olive, and soybean oils-1.5 g/kg/day+1 UI of vitamin E per ml) or water (control) by gavage for 13 weeks. Left ventricular cardiomyocyte number (N[cmn]) was analysed through stereology and disector method.

RESULTS

BP showed lower in the experimental groups (30% in the fish oil group, 15% in both canola oil and palm oil groups, 5% in both olive oil and soybean oil groups) when compared to the control group. N[cmn] was greater in the fish oil group and smaller in the control group. N[cmn] was over 130% greater in the fish oil group, and more than 25% greater in the canola, palm, and olive oils groups compared to the control group. N[cmn] showed a negative correlation with BP (R=-0.98, p<0.01).

CONCLUSION

Hypertension nutritional management and subsequent prevention/attenuation of left ventricular cardiomyocyte loss pointed out a novel therapeutic strategy to be seriously considered in the long-term hypertension treatment. The goal is to postpone the consequences of cardiomyocyte number decrease and heart failure in hypertension.

Effects of long-term intake of edible oils on hypertension and myocardial and aortic remodelling in spontaneously hypertensive rats

BACKGROUND

The nature of dietary lipid intake contributes to blood pressure control.

OBJECTIVE

To test whether different edible lipid compounds are either beneficial or harmful to blood pressure and cardiac and aortic structure.

METHODS

Six groups of 3-month-old male spontaneously hypertensive rats (n = 5) received different edible oils (fish, canola, palm, olive and soybean oils, 1.5 g/kg per day + 1 IU/ml vitamin E) or a placebo (water) by gavage for 13 weeks. Stereology was used to analyse left ventricular cardiomyocytes, intramyocardial vessels, connective tissue, aortic lamellae and tunica media smooth muscle cells.

RESULTS

Fish oil decreased blood pressure, and increases in blood pressure were prevented by both canola and palm oils. The cardiomyocyte and intramyocardial vessel indices were greater in the fish-, canola- and palm-oil groups and smaller in the soybean-oil, olive-oil and control groups; the opposite effects were found in interstitial connective tissue. The number of lamellae was smaller in the fish-oil group but greater in the soybean-oil, canola-oil, and olive-oil groups. Canola oil reduced aortic wall thickness, but palm oil did not. The number of smooth muscle cells was smaller in the groups given fish, canola and olive oils.

CONCLUSION

The most beneficial cardiac and aortic structural effects occurred in the fish-oil group. Both canola oil and palm oil were also effective in reducing blood pressure, favouring myocardial remodelling, although they produced contrasting effects with regard to aorta wall structure. Soybean oil and olive oil had mild effects on myocardial and aortic structure.

Depressed prostanoid-induced contractility of the gut in spontaneously hypertensive rats (SHR) is not affected by the level of dietary fat

Dietary saturated fat (SF) has adverse effects on cardiac and vascular smooth muscle (VSM) contractility. Furthermore, VSM of spontaneously hypertensive rats (SHR) is overreactive to various biological stimuli. The aim of this study was to investigate the effects of increasing dietary fat as lard on gut contractility in SHR. Control Wistar-Kyoto (WKY) rats and SHR (13 wk old) were fed for 12 wk a diet containing 3% sunflower oil [low fat (LF), 3% total fat] or diets supplemented with 7% lard [medium fat (MF), 10% total fat] or 27% lard [high fat (HF), 30% total fat]. For ileal and colonic tissues (WKY and SHR), there was a lower total phospholipid PUFA (n-6)/(n-3) ratio with increased dietary SF (P < 0.003). For WKY, increasing SF led to lower levels of the major SCFA and lower total SCFA levels in cecal digesta (P < 0.01). This trend was evident in SHR but significant only for butyrate (P < 0.01). Contractility responses were unaltered in ileum. In colon, there was a change of sensitivity (50% effective concentration) to angiotensin II in WKY (P < 0.05) due to increased SF and a change of sensitivity to prostaglandin (PG)E(2) and carbachol in SHR (P < 0.05). When the 3 dietary groups were combined, there was lower sensitivity (P < 0.01) and lower maximal contraction (P < 0.05) in ileum and lower maximal contraction in colon of SHR in response to PGF(2alpha) (P < 0.05) and PGE(2) (P < 0.01) compared with WKY. Unlike (n-3) PUFA, dietary SF had little overall effect on gut contractility. However, this is the first report of a defect in PG responsiveness from gut tissue from hypertensive rats.

Role of nuclear receptors in the regulation of gene expression by dietary fatty acids (review)

Long chain fatty acids, derived either from endogenous metabolism or by nutritional sources play significant roles in important biological processes of membrane structure, production of biologically active compounds, and participation in cellular signaling processes. Recently, the structure of dietary fatty acids has become an important issue in human health because ingestion of saturated fats (containing triglycerides composed of saturated fatty acids) is considered harmful, while unsaturated fats are viewed as beneficial. It is important to note that the molecular reason for this dichotomy still remains elusive. Since fatty acids are important players in development of pathology of cardiovascular and endocrine system, understanding the key molecular targets of fatty acids, in particular those that discriminate between saturated and unsaturated fats, is much needed. Recently, insights have been gained on several fatty acid-activated nuclear receptors involved in gene expression. In other words, we can now envision long chain fatty acids as regulators of signal transduction processes and gene regulation, which in turn will dictate their roles in health and disease. In this review, we will discuss fatty acid-mediated regulation of nuclear receptors. We will focus on peroxisome proliferators-activated receptors (PPARs), liver X receptors (LXR), retinoid X receptors (RXRs), and Hepatocyte Nuclear Factor alpha (HNF-4alpha), all of which play pivotal roles in dietary fatty acid-mediated effects. Also, the regulation of gene expression by Conjugated Linoleic Acids (CLA), a family of dienoic fatty acids with a variety of beneficial effects, will be discussed.