Menopause, a cessation of menstrual bleeding, is directly related to serious
illness confined to cardiovascular disease (CVD) such as hypertension and stroke. The oestrogen withdrawal and consumption of high cholesterol diet has
a detrimental effect on cardiovascular function and metabolism in menopausal
women. The present study was aimed to develop the hypertensive rat model in
the ovariectomised Sprague Dawley rats fed with 2% cholesterol diet following a
short term period. Eighteen Sprague-Dawley rats were randomly divided into three
groups; Sham control (sham), ovariectomized control fed with normal diet (Ovx
+N), ovariectomized rats fed with 2% cholesterol diet (Ovx + Cho) for four weeks.
At the end of the study, the food intake and body weight were measured. The
systolic, diastolic and mean blood pressure was determined. OVX+Cho showed
significant increase in physiological changes such as body weight and food intake
compared to Ovx+N group. The significant increase in systolic, diastolic and mean
blood pressure was observed in Ovx+Cho group. Based on the above findings,
it is believed that feeding cholesterol diet for four weeks (short term) results in
significant increase in the blood pressure, food intake and body weight in the
ovariectomised rats.
The concept of mild chronic vascular inflammation as part of the pathophysiology of cardiovascular disease, most importantly hypertension and atherosclerosis, has been well accepted. Indeed there are links between vascular inflammation, endothelial dysfunction and oxidative stress. However, there are still gaps in our understanding regarding this matter that might be the cause behind disappointing results of antioxidant therapy for cardiovascular risk factors in large-scale long-term randomised controlled trials. Apart from the limitations of our knowledge, limitations in methodology and assessment of the body's endogenous and exogenous oxidant-antioxidant status are a serious handicap. The pleiotropic effects of antioxidant and anti-inflammation that are shown by some well-established antihypertensive agents and statins partly support the idea of using antioxidants in vascular diseases as still relevant. This review aims to provide an overview of the links between oxidative stress, vascular inflammation, endothelial dysfunction and cardiovascular risk factors, importantly focusing on blood pressure regulation and atherosclerosis. In view of the potential benefits of antioxidants, this review will also examine the proposed role of vitamin C, vitamin E and polyphenols in cardiovascular diseases as well as the success or failure of antioxidant therapy for cardiovascular diseases in clinical trials.
Twenty eight patients who satisfied the entry criteria and had completed an initial 2 weeks treatment with placebo were titrated fortnightly with doses of Nicardipine ranging from 30 mg to 90 mg daily in two or three divided doses. Nicardipine treatment significantly reduced blood pressures both in the supine and standing positions (p < 0.0004) when compared with placebo treatment. Heart rates however did not change significantly. Forty six percent (13/28) of patients on 20 mg twice daily, 25% (7/28) on 10 mg three times daily, 18% (5/28) of patients on 20 mg three times daily and 11% (3/28) on 30 mg three times daily achieved supine diastolic blood pressures < 90 mm Hg. Nicardipine treatment at 16 weeks and at 24 weeks did not significantly alter the lipid profile when compared to the end of placebo treatment period. No other biochemical abnormalities were reported during the study period. Except for 2 cases of mild pedal oedema and 2 cases of transient headaches, no serious side-effects were encountered.
Consumption of repeatedly heated soy oil has been linked with incidence of atherosclerosis particularly in oestrogen deficient states. In the present study, effect of curcumin extract on the prevention of atherosclerosis was evaluated.
This study examined the effects of a tocotrienol-rich fraction (TRF) obtained from palm oil on the healing of aspirin-induced gastric mucosal lesions. Thirty-six male Sprague-Dawley rats (200-250 g) were randomly divided into three groups. Group I was fed a vitamin E-deficient diet (control), Group II was fed a vitamin E-deficient diet supplemented with tocopherol (300 mg/kg food) and Group III was fed a vitamin E-deficient diet supplemented with TRF (300 mg/kg food). After eight weeks, the control and treated groups received a single intragastric dose of 400 mg/kg body weight aspirin. The rats were killed 24 h after exposure to aspirin. Assessment of gastric lesions showed a lower gastric lesion index in the TRF (P = 0.0005) and tocopherol groups (P = 0.0008) compared to the control. The gastric malondialdehyde (MDA) content was also lower in the TRF (P = 0.025) and tocopherol groups (P = 0.025) compared to control. There were, however, no significant differences in the gastric lesion index and gastric MDA content between the TRF and tocopherol-fed groups. There were no significant differences in the adherent gastric mucous concentration and gastric acid concentration among all groups. We conclude that the TRF and tocopherol are equally effective in preventing aspirin-induced gastric lesions. The most probable mechanism is through their ability to limit lipid peroxidation, which is involved in aspirin-induced gastric lesions.
The use of repeatedly heated frying oils and intake of high cholesterol diet have been linked to bone damage. The aim of this study is to determine the combined effects of taking repeatedly heated frying oils (palm or soy oil) and high cholesterol diet on the dynamic histomorphometric parameters of bone. Ovariectomised rats were used as animal model of post-menopausal osteoporosis. After six months of treatment, Double-labeled Surface (dLS/BS), Mineralising surface (MS/BS) and Bone Formation Rate (BFR/BS) of ovariectomised rats (OvxC) were significantly reduced compared to the normal control group. Additions of fresh or once-heated palm or soy oil into high cholesterol diet seem to have improved the dynamic parameters towards the normal control values. However, when these oils were repeatedly heated, the protective effects were lost and the dynamic parameters except MS/BS dropped back towards the ovariectomised-control values.
It has been a regular practice to repeatedly heat the cooking oil and consume it without knowing the harmful effects of such. The procedure to use repeatedly heated cooking oil is aimed to curb the cost of expenses. Heating results is the formation of free reactive oxygen species (ROS) which is responsible for the oxidative stress and damage to various organs in the body. The present review article discusses the harmful events occurring due to consumption of repeated heating of edible oil. A strong message is aimed to generate public awareness of the deleterious effects of consumption of heated edible oil which may help in curbing hypertension and atherosclerosis.
In a single-blind study conducted at our centres, 78 hypertensive patients were enrolled with 58 completing the study according to the protocol. Mean supine and standing blood pressures were significantly reduced after treatment with felodipine, reductions being 27/21 mmHg (p < 0.0001) and 25/19 mmHg (p < 0.0001) respectively. Of 46 patients given felodipine 5 mg, 44 (95.7%) achieved target blood pressure defined as a diastolic blood pressure of < 90 mmHg, while all 12 patients on felodipine 10 mg did so. The 2 patients who did not achieve target pressure at the final visit did so on previous visits. There were no differences in pre and post-treatment laboratory variables. Treatment was discontinued in 6 patients because of headaches. No adverse events of clinical significance were reported in the 58 patients who completed the study. In conclusion, we found felodipine given once daily to be effective in the treatment of mild to moderate hypertension.
To determine the association between carotid femoral pulse wave velocity (PWVCF); augmentation index (AI); and high-sensitivity C reactive protein (hs-CRP) with metabolic syndrome (MetS), and to determine the influence of ethnicity on PWVCF and AI, and the association between high hs-CRP and increased PWV, and AI in MetS.