Abresham ameliorates dyslipidemia,hepatic steatosis and hypertension in high-fat diet fed rats by repressing oxidative stress,TNF-α and normalizing NO production

This study was aimed to investigate whether standardized hydroalcoholic extract of abresham (AB) ameliorates dyslipidemia, hepatic steatosis and associated hypertension in rats fed with high-cholesterol/high-fat diet (HFD). HFD (55% calorie from fat and 2% cholesterol) were fed for 45 days to induce dyslipidemia, hepatic steatosis and associated hypertension. After confirmation of hypercholesterolemia (total cholesterol >150 mg/dl) on 30th day, different doses of AB (200–800 mg/kg/day) were administered for next 15 days. HFD administration for 45 days led to cardiometabolic syndrome characterized by significant increase in body weight, total cholesterol, triglyceride, low density lipoprotein cholesterol, TNF-α levels along with decrease in high density lipoprotein cholesterol and serum NO level. Furthermore, HFD resulted in significant increase in systolic arterial pressure, diastolic arterial pressure and mean arterial pressure. In addition, morphological studies revealed hepatic steatosis along with swelling of mitochondria and loss of cristae in hepatocyte and periarteritis in aorta. Treatment with AB for 15 days positively modulated the altered parameters in dose-dependent fashion, though maximum effect was seen at 800 mg/kg. These findings suggest that AB guard against cardiometabolic syndrome in HFD fed rats. It attenuates dyslipidemia, hepatic steatosis and associated hypertension by decreasing oxidative stress, TNF-α and normalizing NO production.     

Further reduction of low-density lipoprotein cholesterol and C-reactive protein with the addition of ezetimibe to maximum-dose rosuvastatin in patients with severe hypercholesterolemia

BackgroundPatients with severe hypercholesterolemia, including familial hypercholesterolemia, are considered at high risk for coronary artery disease and often prove difficult to treat to current low-density lipoprotein cholesterol (LDL-C) guidelines.MethodsIn this open-label, 12-week substudy within a larger trial, ezetimibe 10 mg was added to stable therapy with rosuvastatin 40 mg (± bile acid sequestrant/niacin) in 107 patients with severe hypercholesterolemia who had not achieved LDL-C goal of <100 mg/dL.ResultsPrior to the start of rosuvastatin treatment, on diet alone, mean LDL-C levels were 291 ± 59 mg/dL and decreased to 141 ± 30 mg/dL on rosuvastatin 40 mg daily at the substudy baseline prior to ezetimibe. After 12 weeks, the addition of ezetimibe produced an additional 15% ±9% reduction in LDL-C (P < 0.001) compared to pre-rosuvastatin levels and a mean LDL-C of 103 ± 27 mg/dL, resulting in 59% of patients reaching their LDL-C goals. The combination reduced LDL-C by 65% ± 9% from diet alone. Combination with ezetimibe also produced significant additional percent reductions in non–high-density lipoprotein (14%), apolipoprotein B (10%), and triglycerides (6%). Median C-reactive protein was reduced 54% (P < 0.001) by the combination compared with diet alone, a further incremental reduction of 13% (P < 0.001) with the addition of ezetimibe. The combination was well tolerated, with no patients developing myopathy or clinically significant elevations of creatine kinase or transaminases.ConclusionsThe combination of rosuvastatin 40 mg and ezetimibe 10 mg offers the most effective LDL-C–lowering therapy yet reported, and is helpful in achieving lipid goals and reducing C-reactive protein levels in high-risk patients with severe hypercholesterolemia, including familial hypercholesterolemia.     

Dietary tomato and grape pomace in rats: effect on lipids in serum and liver, and on antioxidant status

Addition of tomato and grape pomace to the cholesterol (0.3%) diet of male Wistar rats produced a dose-dependent effect. During the eight-week experiment, 5% pomace showed no effect; however, 15% pomace reduced serum cholesterol levels from 4.4 mmol/L to 2.5 mmol/L (tomato) and 2.0 mmol/L (grape). At a concentration of 15%, both tomato and grape pomace induced a redistribution of cholesterol in lipoproteins, resulting in a pronounced anti-atherogenic profile: reduced cholesterol concentration in very-low-density lipoprotein (VDL) (24% [tomato], 50% [grape]) and low-density lipoprotein (LDL) (3-fold, 3.6-fold). In addition, grape pomace increased cholesterol concentration in high-density lipoprotein (HDL) by 26%. Both types of pomace reduced the VLDL and LDL contribution to cholesterol transport in favour of HDL. Grape pomace (15%) produced a significant reduction in cholesterol and triacylglycerols in the liver and serum respectively. Diets containing tomato and grape pomace reduced plasma levels of conjugated dienes by 30-50%, and showed a tendency towards higher superoxide dismutase and glutathione peroxidase activity in the liver.     

Self-expandable nitinol stent placement in homocysteinemic porcine aorta

PURPOSE: To compare aortic intimal thickening of normal and hyperhomocysteinemic pigs (induced with a methionine-rich diet) following placement of a self-expanding nitinol stent. METHODS: Eighteen Macau pigs were used. They were older than eight weeks in age and had an average weight of 30 kg. Pigs were randomly divided into two groups. The first, Group C (control), was fed a regular diet, and the second group, Group M, was fed a methionine-rich diet for 30 days to induce hyperhomocysteinemia. The self-expandable nitinol stents were 25mm in length and 8 mm in diameter after expansion. Blood samples were collected to measure total cholesterol, triglycerides, HDL and homocysteine concentrations. All animals were subjected to angiography. Thirty days after the procedure, the animals were sacrificed, and the abdominal aorta was removed for histological and digital morphometry analysis. RESULTS: Under microscopic evaluation, the intima was significantly thicker in Group C than in Group M. When groups were compared by digital morphometric analysis, intimal thickening of the vessel wall was higher in Group C than in Group M. There was no significant change in total cholesterol, triglycerides or HDL concentrations in either group. In group C the levels of plasma homocysteine ranged from 14,40 to 16,73 micromol/l; in Group M, plasma homocysteine levels ranged from 17.47 to 59.80 micromol/l after 30 days of a methionine-rich diet. CONCLUSION: Compared to normal pigs, less intimal hyperplasia was observed in the abdominal aortas of hyperhomocysteinemic pigs thirty days after the insertion of a self-expandable nitinol stent.     

Dietary induced hyperbetalipoproteinemia in chimpanzees: comparison to the human hyperlipoproteinemia

Fasting plasma from chimpanzees fed normal and atherogenic diet was separated into alpha (HDL) and beta (LDL) lipoproteins by electrochromatography. Both lipoproteins were analyzed for lipid and fatty acid composition.Beta lipoproteins, esterified cholesterol, free cholesterol, and phospholipids were increased in chimpanzees fed the atherogenic diet. The cholesterol/phospholipid ratio was increased. These lipid changes occurred chiefly in the beta lipoproteins. A disproportionate increase of plasma phosphatidylcholine to sphingomyelin was confirmed. Differences in the fatty acid composition of both lipoproteins were noted and cholesterol oleate was elevated more than cholesterol linoleate so that the $\text{18:1}\text{18:2}$ ratio was increased. The intima of one animal which died from myocardial infarction after 4–5 years diet showed an increase of cholesterol oleate.Similarities between cholesterol-induced lipoprotein changes in chimpanzees and those obtained in human hyperbetalipoproteinemia are discussed. These similarities stress the usefulness of these nonhuman primates as a model for experimental atherosclerosis and for studying the molecular changes in lipoprotein patterns.     

A study of atherosclerosis regression in Macaca mulatta. I. Design of experiment and lesion induction.

Rhesus monkeys were fed an atherogenic diet containing 40% of calories from lard and 1.0 mg/Cal cholesterol for either 19 months (Colony I) or 38 months (Colony II). At the end of the induction period the animals from each colony were divided into three groups (A, B, C) on the basis of total plasma cholesterol concentration during the induction period. Group A animals were killed at the end of the induction period for baseline observation of the extent and severity of atherosclerosis. Group B from each colony was fed a diet which maintained total mean plasma cholesterol concentrations between 280 to 320 mg/dl comparable to human beings with modest hyperlipoproteinemia. Group C from each colony was fed a diet which maintained total mean plasma cholesterol concentrations between 180 to 220 mg/dl, comparable to people who had modest hyperlipoproteinemia but were able to reduce plasma cholesterol concentrations by approximately 100 mg/dl using diet or drugs. Each group was further divided into two subgroups (B₁, B₂, and C₁, C₂). Animals from subgroup 1 were fed these diets for 24 months and animals from subgroup 2 were fed the same diet for 48 months.This report describes the clinical history, chemical analyses of arteries and the morphological extent and severity of atherosclerosis in arteries from animals of both colonies at the end of the induction period.     

天麻细粉和天麻素降血脂作用的实验研究

目的研究天麻细粉、天麻素的降血脂作用。方法采用金黄地鼠饲喂高脂饲料,分为正常对照组、高脂对照组(HF)、阳性对照组(舒降之)5.0mg/kg,天麻细粉125mg/kg、250mg/kg、500mg/kg、天麻素12.5mg/kg、25.0mg/kg、50.0mg/kg组,口服给药14d取血清测定总胆固醇(TC)、甘油三脂(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)含量。结果天麻细粉和天麻素各剂量组均能降低高脂血症金黄地鼠血清中TC、TG、LDL-C含量,LDL-C/HDL-C比值、动脉硬化指数AI减小,均有显著性差异(P0.01及P0.05)。结论天麻细粉、天麻素具有降血脂作用。     

Repeated Systemic <Emphasis Type="Italic">Escherichia coli</Emphasis> Infection Enhances Anti-oxidant Response in Hypercholesterolemic Mice Inducing Cardiovascular Inflammation

It has been well established that diet high in cholesterol and saturated fatty acids could significantly elevate plasma cholesterol levels and also increase the risk of cardiovascular diseases. We hypothesize that repeated systemic Escherichia coli (E. coli) in conjunction with hypercholesterolemia, leads to development of oxidative stress that may affect the development and progression of inflammatory CVD. Swiss albino mice (4 weeks old) were randomly assigned to high cholesterol diet (HCD) or normal laboratory diet (NLD) groups. At 10 weeks of age, mice were inoculated intravenously with E. coli or vehicle for 24 weeks. Serum cholesterol, low density lipoprotein, C reactive protein levels, blood glucose level and selective antioxidant enzymes throughout the systemic infection period in murine aorta, heart and liver during hypercholesterolemia, were examined. Serum cholesterol levels were elevated in HCD-fed mice, compared to NLD. The blood colony forming units (CFU) of E. coli suggested persistence of systemic infection. The antioxidant enzyme levels were elevated in E. coli infected groups as compared to controls. The myeloperoxidase content of aortic tissue was significantly higher in all groups infected with E. coli. Our study suggests that during hypercholesterolemia, repeated systemic E. coli infection induces an endogenous antioxidant response that serves to modulate vascular inflammation leading to cardiovascular diseases.     

Rejuvenation of antioxidant system in central nervous system of aged rats by grape seed extract

Oxidative stress is considered as a major risk factor that contributes to age-related increase in lipid peroxidation and declined antioxidants in the central nervous system during aging. Grape seed extract, one of the bioflavonoid, is widely used for its medicinal properties. In the present study, we evaluated the role of grape seed extract on lipid peroxidation and antioxidant status in discrete regions of the central nervous system of young and aged rats. Male albino rats of Wistar strain were divided into four groups: Group I-control young rats, Group II-young rats treated with grape seed extract (100 mg/kg body weight) for 30 days, Group III-aged control rats and Group IV-aged rats supplemented with grape seed extract (100 mg/kg body weight) for 30 days. Age-associated increase in lipid peroxidation was observed in the spinal cord, cerebral cortex, striatum and the hippocampus regions of aged rats (Group III). Activities of antioxidant enzymes like superoxide dismutase, catalase, glutathione peroxidase and levels of non-enzymic antioxidants like reduced glutathione, Vitamin C and Vitamin E were found to be significantly decreased in all the brain regions studied in aged rats when compared to young rats. However, normalized lipid peroxidation and antioxidant defenses were reported in the grape seed extract-supplemented aged rats. These findings demonstrated that grape seed extract enhanced the antioxidant status and decreased the incidence of free radical-induced lipid peroxidation in the central nervous system of aged rats.     

Vitamin E attenuates homocysteine and cholesterol induced damage in rat aorta

BackgroundThe aim of this study was to investigate the effect of vitamin E on homocysteine and cholesterol-induced damage of rat aorta.MethodsWistar rats (all fed with a vitamin E poor diet) were divided into five groups. Control group was fed with the diet only, the second group received 1 mg kg^?1 day^?1 l-methionine in drinking water, the third group was fed with 2% cholesterol containing diet, the fourth group received l-methionine and cholesterol together, and the fifth group was fed with l-methionine and cholesterol and received intramuscular injections of vitamin E. After 4 weeks serum homocysteine, cholesterol and vitamin E levels were measured; aortas were removed; collagen and elastin and the major extracellular matrix components were evaluated microscopically as indicators of aortic degeneration. Aortic collagen content was measured by a colorimetric hydroxyproline assay.ResultsFour-week diet supplementation with methionine and cholesterol caused a twofold increase in serum homocysteine and 22% increase in serum cholesterol levels; endothelial damage and degenerative alterations in the aortic media were observed, as indicated by the dissociation of elastic fibers and accumulation of collagen. Vitamin E completely prevented the accumulation of collagen and largely prevented aorta damage as shown by the morphological data.ConclusionThe results indicate that, even moderate increases in homocysteine and cholesterol levels are sufficient to induce vascular degeneration that may be prevented by vitamin E supplementation.     

Diet induced atherogenic hyperlipoproteinaemia and liver injury in cynomolgus macaques.

This study was conducted to determine the efficacy of an experimental anti-atherosclerosis drug in the adult male cynomolgus monkey. A semipurified diet containing 0.5% cholesterol and 25.5% butter was fed to groups of 20, each, drug and placebo-treated animals for 18 months. Similar liver and arterial changes were present in both groups. However, we report here tissue changes seen in animals given placebo only, with plasma lipid and lipoprotein values of placebo-treated animals compared to those in animals fed nonatherogenic commercial ration. Animals fed atherogenic diet had enlarged livers (mean 3.9% b.w.), and all had evidence of hepatocellular lipid accumulation which was often marked and diffuse. Cholangitis was common including mononuclear cell infiltration, bile ductule proliferation and portal tract fibrosis. Five animals had severe portal fibrosis with bands of connective tissue extending into and around lobules (bridging fibrosis). All animals fed atherogenic diet developed hypercholesterolemia (greater than 600 mg/dl) which was the result of a three-fold increase in five cholesterol and cholesterol ester. Oleic acid was increased and linoleic acid was reduced in plasma phospholipids and cholesterol esters. Plasma lipoprotein distribution was altered with a marked increase in low density lipoproteins, increased very low density lipoproteins and decreased high density lipoproteins. These changes were undoubtedly caused by diet, i.e., high in cholesterol and saturated fat and limiting in linoleic acid. It is probable that diet-induced liver injury would affect the pathogenesis of atherosclerosis in this model since the liver is central in the synthesis and metabolism of lipoproteins.     

Diet induced atherogenic hyperlipoproteinaemia and liver injury in cynomolgus macaques

This study was conducted to determine the efficacy of an experimental anti-atherosclerosis drug in the adult male cynomolgus monkey. A semipurified diet containing 0.5% cholesterol and 25.5% butter was fed to groups of 20, each, drug and placebo-treated animals for 18 months. Similar liver and arterial changes were present in both groups. However, we report here tissue changes seen in animals given placebo only, with plasma lipid and lipoprotein values of placebo-treated animals compared to those in animals fed nonatherogenic commercial ration. Animals fed atherogenic diet had enlarged livers (mean 3.9% b.w.), and all had evidence of hepatocellular lipid accumulation which was often marked and diffuse. Cholangitis was common including mononuclear cell infiltration, bile ductule proliferation and portal tract fibrosis. Five animals had severe portal fibrosis with bands of connective tissue extending into and around lobules (bridging fibrosis). All animals fed atherogenic diet developed hypercholesterolemia (greater than 600 mg/dl) which was the result of a three-fold increase in five cholesterol and cholesterol ester. Oleic acid was increased and linoleic acid was reduced in plasma phospholipids and cholesterol esters. Plasma lipoprotein distribution was altered with a marked increase in low density lipoproteins, increased very low density lipoproteins and decreased high density lipoproteins. These changes were undoubtedly caused by diet, i.e., high in cholesterol and saturated fat and limiting in linoleic acid. It is probable that diet-induced liver injury would affect the pathogenesis of atherosclerosis in this model since the liver is central in the synthesis and metabolism of lipoproteins.     

Role of Momordica charantia in maintaining the normal levels of lipids and glucose in diabetic rats fed a high-fat and low-carbohydrate diet

This study aims to assess whether or not a methanol extract of Momordica charantia is able to normalise lipid and glucose levels in diabetic rats fed a high-fat and a low-carbohydrate diet. Different doses of the extract are administered orally for 45 days. The rats are bled at the beginning of the experiment and at 15-day intervals. Blood glucose, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and cholesterol are estimated. Results showed that M. charantia extract normalised blood glucose level, reduced triglyceride and LDL levels and increased HDL level. The animals reverted to a diabetic state once the M. charantia extract was discontinued.     

Antioxidant and anti-atherogenic activities of three Piper species on atherogenic diet fed hamsters

Atherogenic diet is known to induce high plasma lipid concentration, oxidative stress and early atherosclerosis. Antioxidants have potentials to counter the effect of atherogenic diet.The present research aims at evaluating the antioxidant and anti-atherosclerotic activities of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) on atherogenic diet fed hamsters.Hamsters divided into 8 groups: normal control, atherosclerotic control and six test groups. The normal animals fed normal rodent chow, the atherosclerotic control animals fed the same rodent chow supplemented with 0.2% cholesterol and 10% coconut oil (high cholesterol diet). The 6 test groups’ animals fed same diet as the atherosclerotic control group but with additional supplementation of 2 graded doses (1 and 0.25 mg/kg body weight, o.p.) of plant extracts for 12 weeks.The atherogenic diet induced a collapse of the erythrocyte antioxidant defense system (significant decrease in superoxide dismutase, catalase and glutathione peroxidase activities). Atherogenic diet also induced an increase in plasma total cholesterol, triglyceride, thiobarbituric acid reactive substances (TBARS), oxidation of low density lipoprotein cholesterol (LDL) and accumulation of foam cells in the aorta a hall mark for atherosclerosis. Administration of the Piper species prevented the collapse of the antioxidant system and the increase of plasma parameters maintaining them towards normality. The Piper species also prevented LDL oxidation by increasing the time (lag time) for its oxidation.The results suggest that these Piper species have significant antioxidant and anti-atherogenic effect against atherogenic diet intoxication.     

Cigarette smoke-induced depression in LCAT activity

The effect of acute inhalation of cigarette smoke on plasma cholesterol esterification by lecithin-cholesterol acyltransferase (LCAT) in atherosclerosis-susceptible White Carneau pigeons was examined. Pigeons were assigned to four treatment groups: (1) Shelf Control fed a chow diet and not exposed to smoke products; (2) Sham pigeons fed a cholesterol-saturated fat diet and exposed to fresh air by the Lorillard smoking machine; (3) low nicotine-low carbon monoxide (LoLo) animals also fed the cholesterol diet and exposed to low concentrations of these cigarette smoke products; and (4) high nicotine-high carbon monoxide (HiHi) birds fed the cholesterol diet and subjected to high concentrations of these inhalants. Both Control and Sham birds had significantly higher LCAT activity (percentage esterification per minute) than HiHi pigeons. Experiments designed to determine whether altered enzyme and/or substrate were responsible for depressed activity revealed no smoke-related modification in substrate efficiency. In addition, Sham and HiHi pigeons had similar concentrations of plasma-free cholesterol, high density lipoprotein (HDL) cholesterol, cholesteryl ester and phospholipid, and similar HDL phospholipid and cholesteryl ester fatty acid profiles. However, reduced LCAT activity in HiHi pigeons can be explained by (1) impairment of enzyme efficiency as estimated by in vitro analysis; and (2) in vivo reduction in levels of LCAT cofactor, HDL apoprotein A-I.     

Blockade of endothelin receptors reduces diet-induced hypercholesterolemia and atherosclerosis in apolipoprotein E-deficient mice.

OBJECTIVE: Endothelin (ET)-1 has proatherogenic properties, since ET receptor antagonists reduce atherosclerotic lesions in animals. However, we recently demonstrated that ET-1 and ET(B) receptors are increased in atherosclerotic lesions. To further examine the effects of ET(B) receptor antagonism on atherogenesis, we investigated the chronic effects of the nonselective ET(A)/ET(B) receptor antagonist SB209670 on the development of atherosclerosis in apolipoprotein E (ApoE)-deficient mice. METHODS: Ninety-four male mice (10 weeks of age) were randomly divided into four groups: mice fed a Western-type diet or a chow diet with SB209670 treatment (10 mg/kg/day) or placebo for 12 weeks. RESULTS: In mice fed the Western-type diet, but not in mice fed the chow diet, treatment with SB209670 significantly attenuated the increase in plasma total cholesterol, predominantly in the very-low-density lipoprotein and intermediate-density lipoprotein fractions, without altering the plasma triglyceride level. Furthermore, treatment with SB209670 significantly reduced the extent of aortic atherosclerosis, by 53% in mice fed the Western-type diet and by 38% in mice fed the chow diet. Histological analysis revealed that SB209670 prevented the formation of atheromatous plaque lesions by inhibiting the fibroproliferative process. CONCLUSION: We found that chronic administration of SB209670 reduced diet-induced hypercholesterolemia and atherosclerosis in ApoE-deficient mice. Thus, nonselective ET receptor antagonists may have a therapeutic potential in the treatment of human atherosclerotic disease.     

Unusual resistance of the ground squirrel to the development of dietary-induced hypercholesterolemia and atherosclerosis

This study was designed to examine the apparently unusual resistance to atherosclerosis in the adult male ground squirrel. In one study, serum lipid and lipoprotein patterns and concentrations of ground squirrels were observed after feeding for 26 weeks with either rodent chow or rodent chow supplemented with cholesterol. These two groups were compared to a third group fed chow diet for three weeks, then killed for baseline values to distinguish between aging effects and those induced by cholesterol feeding. No outstanding changes in the concentration and patterns of the serum cholesterol, triglycerides, and lipoproteins were observed in any groups. A higher serum phospholipid concentration in cholesterol-fed animals compared to animals fed chow diet alone for three weeks suggested that the rise was associated with aging rather than diet. The predominant lipoprotein fraction in all three groups was high-density lipoprotein (HDL). No lesions were found in the coronary arteries or thoracic and abdominal aortas.In a second study a primate diet with 50% egg yolk was given for 1 year. This diet caused elevation of serum cholesterol and phospholipid levels, and increased HDL, which had an unusual ability to carry as much cholesterol as the low-density lipoprotein (LDL). However, no arterial lipid accumulation was observed. Light microscopic and ultrastructural studies of the coronary artery and aorta revealed nothing unusual, and in structure, they resembled those of other small rodents. The only striking finding was that very few degenerative aging changes were found in the aorta when compared to rats of a similar age. The study demonstrates that the ground squirrel does not develop marked hypercholesterolemia with cholesterol feeding and that the majority of the elevated levels of serum lipids, particularly cholesterol, are transported as α-lipoprotein. Both of these factors, plus the lack of degenerative aging changes in the arterial wall may play an important role in the resistance of this particular species to atherosclerosis.     

Hypercholesterolemic LDL receptor-deficient mice mount a neutrophilic response to tuberculosis despite the timely expression of protective immunity

The prevalence of hypercholesterolemia is rising in industrialized and developing countries. We reported previously that host defense against Mtb was impaired by hypercholesterolemia in ApoE(-/-) mice, raising the possibility that people with HC could be more vulnerable to TB. The present study examined whether TB immunity was similarly impaired in a different hypercholesterolemic model, LDL-R(-/-) mice, which developed comparable elevation of total serum cholesterol as ApoE(-/-)mice when fed HC or LC diets. Like ApoE(-/-) mice, LDL-R(-/-) mice had an exaggerated lung inflammatory response to Mtb with increased tissue necrosis. Inflammation, foamy macrophage formation, and tissue necrosis in LDL-R(-/-) mice increased with the degree of hypercholesterolemia. Unlike ApoE(-/-) mice, LDL-R(-/-) mice fed a HC diet mounted a timely and protective adaptive immune response that restricted mycobacterial replication comparably with WT mice. Thus, ApoE(-/-) and LDL-R(-/-) mice share a cholesterol-dependent hyperinflammatory TB phenotype but do not share the impairment of adaptive immunity found in ApoE(-/-) mice. The impact of hypercholesterolemia on TB immunity is more complex than appreciated by total cholesterol alone, possibly reflecting the different functional effect of specific lipoprotein particles.     

Whole plant based treatment of hypercholesterolemia with Crataegus laevigata in a zebrafish model

ABSTRACT: BACKGROUND: Consumers are increasingly turning to plant-based complementary and alternative medicines to treat hypercholesterolemia. Many of these treatments are untested and their efficacy is unknown. This multitude of potential remedies necessitates a model system amenable to testing large numbers of organisms that maintains similarity to humans in both mode of drug administration and overall physiology. Here we develop the larval zebrafish (4-30 days post fertilization) as a vertebrate model of dietary plant-based treatment of hypercholesterolemia and test the effects of Crataegus laevigata in this model. METHODS: Larval zebrafish were fed high cholesterol diets infused with fluorescent sterols and phytomedicines. Plants were ground with mortar and pestle into a fine powder before addition to food. Fluorescent sterols were utilized to optically quantify relative difference in intravascular cholesterol levels between groups of fish. We utilized the Zeiss 7-Live Duo high-speed confocal platform in order to both quantify intravascular sterol fluorescence and to capture video of the heart beat for determination of cardiac output. RESULTS: In this investigation we developed and utilized a larval zebrafish model to investigate dietary plant-based intervention of the pathophysiology of hypercholesterolemia. We found BODIPY-cholesterol effectively labels diet-introduced intravascular cholesterol levels (P < 0.05, Student's t-test). We also established that zebrafish CO declines as CH dose increases (difference between 0.1% and 8% (w/w) high cholesterol diet-treated cardiac output significant at P < 0.05, 1-way ANOVA). Using this model, we found hawthorn leaves and flowers significantly reduce intravascular cholesterol levels (P < 0.05, 1-way ANOVA) and interact with cholesterol to impact cardiac output in hypercholesterolemic fish (2-way ANOVA, P<0.05 for interaction effect). CONCLUSIONS: The results of this study demonstrate that the larval zebrafish has the potential to become a powerful model to test plant based dietary intervention of hypercholesterolemia. Using this model we have shown that hawthorn leaves and flowers have the potential to affect cardiac output as well as intravascular cholesterol levels. Further, our observation that hawthorn leaves and flowers interact with cholesterol to impact cardiac output indicates that the physiological effects of hawthorn may depend on diet.