The antiatherogenic, renal protective and immunomodulatory effects of purslane, pumpkin and flax seeds on hypercholesterolemic rats
The antiatherogenic, renal protective and immunomodulatory effects of purslane, pumpkin and flax seeds on hypercholesterolemic rats
Year: 2011
Authors: Lamiaa, A Barakat, A. Hamed Mahmoud, R.
Publication Name: N Am J Med Sci
Publication Details: Volume 3; Number 9; Pages 411 – 417.
Abstract:
Atherosclerosis remains one of the leading causes of death all over the world. Flax, pumpkin and purslane seeds are rich sources of unsaturated fatty acids, antioxidants and fibers, known to have antiatherogenic activities. This study was to examine the efficiency of using either flax/pumpkin or purslane/pumpkin seed mixture (components of omega 3 and omega 6) on hyperlipidemia, kidney function and as immunomodulators in rats fed high cholesterol diets.
40 male albino rats were divided into four groups: control group, hypercholesterolemic rats, fed the balanced diet supplemented with cholesterol at a dose level of 2 g/100 g diet; the other two groups of animals fed the same previous hypercholesterolemic diet supplemented with either flax/pumpkin seed mixture or pumpkin/purslane seed mixture at ratio of (5/1) (omega 3 and omega 6). The present study showed that 2% cholesterol administration caused a significant increase in total cholesterol, total lipids, and triacylglycerol in both serum and liver. Serum phospholipids, LDL C, and atherogenic index AI also significantly increased compared to control group. Cholesterol-enriched diet significantly increased serum urea, creatinine, sodium and potassium levels as well as significantly increased serum IgG and IgM compared to healthy control. Consumption of flax/pumpkin or purslane/pumpkin seed mixtures by hypercholesterolemic rats resulted in a significantly decrement in lipid parameters and significant improvement in IgG and IgM levels as compared with hypercholesterolemic rats. Our results suggests that both flax/pumpkin and purslane/pumpkin seed mixtures had anti-atherogenic hypolipidemic and immunmodulator effects which were probably mediated by unsaturated fatty acids (including alpha linolenic acid) present in seed mixture. (Authors abstract)
Abnormal lipid metabolism is a main cause of dyslipidemia, which is a major risk factor for cardiovascular disease, obesity, cholesthiasis and overall mortality. It is well known that diet plays an important role in the control of cholesterol homeostasis. It is important to have a balance of omega 3 and omega 6 in the diet. The typical American diet tends to contain 14 to 25 times more omega 6 fatty acids than omega 3 fatty acids. Flaxseed (Linum usitatissimum), also known as linseed, contains 32 to 45% of its mass as oil of which 51 to 55% is alpha linolenic acid (ALA) (18:3 Omega 3 fatty acid), a precursor to eicosapentanoic acid (EPA), as well as being a good source of dietary fibers and lignans. Clinical conditions such as cardiovascular disease, blood pressure, cancer, skin diseases and immune disorders such as renal failure, rheumatoid arthritis and multiple sclerosis may be prevented by ALA in flaxseed oil. Pumpkin seed and seed oil have been implicated in providing many health benefits, which are attributed to their macro and micro constituent composition. They are a rich natural source of proteins, phytosterols, polyunsaturated fatty acids, antioxidant vitamins such as carotenoids and tocopherols. Portulaca oleracea (Portulacaceae family), also referred to the common purslane, contains alkaloids, omega 3 fatty acids, vitamins (mainly vitamin A, vitamin C, and some vitamin B and carotenoids), as well as dietary minerals, such as magnesium, calcium, potassium and iron. In this study, pumpkin seed were used as a source of omega 6 fatty acids, while purslane or flax seeds were used as sources of omega 3 fatty acids. The objective of the current study was to examine the efficiency of using either flax/ pumpkin or purslane/pumpkin seed mixture on hyperlipidemia, kidney function and as immunomodulators in rats fed high cholesterol diets. Cholesterol enriched diet resulted in a significant increase in total cholesterol, total lipids, phospholipids and triacylglycerol in plasma and liver this accompanied by increased serum LDL C level, with decreased circulating HDL C, strong risk factors for coronary heart disease. The current results indicated that both flax/pumpkin and purslane/pumpkin seed mixture had a strong hypolipidemic, hypotriglyceridemic and hypocholesterolemic effects in plasma and liver of rats with a reduction of plasma LDL C levels and an increase in HDL-C levels. Furthermore, the atherogenic index markedly decreased due to significant reduction in LDL/HDL ratio in both groups fed hypercholesterolemic diet supplemented with either flax/pumpkin or purslane/pumpkin seed mixture. The decline in hepatic cholesterol levels in flax/pumpkin hypercholesterolemic group indicated the possible influence of relatively higher fiber content of seed mixture. The increase in HDL-C observed might be due to stimulation of pre-β HDL-C and reverse cholesterol transport. High HDL-C levels could potential contribute to its anti atherogenic properties, including its capacity to inhibit LDL oxidation and protect endothelial cells from the cytotoxic effects of oxidized LDL. The anti atherogenic effect of flax and pumpkin seed mixture found might be due to the presence of polyunsaturated fatty acids, phytosterols, tocopherols and β-carotene. The major total fatty acids present in seed mixture are unsaturated fatty acids such as oleic acid, linolenic acid and linolenic acid which play a crucial role in reducing blood cholesterol in human and rats. Creatinine, synthesized in the liver, passes into the circulation where it is taken up almost entirely by the skeletal muscles. Its retention in the blood is an evidence of kidney impairment. Therefore, the reduced levels of creatinine in serum may imply that, the seed mixture had interfered with creatinine metabolism and its eventual excretion from the blood. The increase in serum urea level in hypercholesterolemic control group indicates impairment in the normal kidney function of the animal, as the mechanism of removing it from the blood might have been affected. Flaxseed could potentially inhibit various mechanisms associated with the progression of renal diseases.The current study showed that the levels of IgG and IgM were significantly increased in hypercholesterolemic rats as compared with healthy control. Seed mixtures either F/P or P/P had positive impacts to the immunity status of hypercholesterolemic rats by significant reduction in rat serum immunoglobulines to bring them near the normal levels. These results show that the seed mixtures exhibit anti-inflammatory and immunomodulating activities. Results showed that ALA is important in preventing heart attacks and strengthening the immune system. (Editors comments)
