Effects of dietary soybean lecithin on plasma lipid transport and hepatic cholesterol metabolism in rats

Effects of lysolecithins on performance, egg quality, blood profiles and liver histopathology in late-phase laying hens

1. This study investigated the effects of lysolecithins (LL) on performance, egg quality, blood profiles, relative organ weight and liver histopathology in laying hens.2. A total of 480 healthy 65-week-old Lohmann laying hens were randomly allocated into four treatments in a 2 × 2 factorial arrangement design with two levels of energy (AMEn, 11.08 MJ/kg and 12.94 MJ/kg) and two levels of LL (0 and 0.05%).3. Birds fed high energy diets had lower (P < 0.05) average daily intake and feed conversion rate during weeks 0-4, 5-8 and 0-8, but higher (P < 0.05) average egg weight (AEW) during trial weeks 0-4. There was an interaction in (P < 0.05) AEW during trial weeks 0-14 and 0-8 for energy and LL. The high energy diets increased yolk colour at the end of weeks 2 and 4, while addition of LL increased albumen height at the end of week 2. There was an interaction (P < 0.05) in yolk colour between energy and LL at the end of week 2. There was an interaction (P < 0.05) in serum superoxide dismutase and LDL-C throughout the experiment.4. The high energy diets increased (P < 0.05) the relative weight of abdominal fat compared with low energy diets. The high energy diets increased (P < 0.05) liver ether extract content and liver pathological injury score compared with low energy diets at the end of week 8, while the addition of LL decreased (P < 0.05) liver pathological injury score.5. The supplementation of LL in high energy diets could alleviate some negative effects on liver injury in late laying hens.

Medicinal plants and bioactive natural compounds as inhibitors of HMG-CoA reductase: A literature review

Cardiovascular diseases (CVDs) are one of the most important causes for mortality worldwide. Elevated levels of total cholesterol, and particularly LDL-cholesterol (LDL-C) are the main risk factor for acute myocardial infarction (AMI) and ischemic heart disease. The risk of CVDs could be reduced by decreasing the elevated cholesterol levels. β-hydroxy β-methylglutaryl-CoA reductase (HMGCoAR) is the primary and rate-limiting enzyme in the cholesterol biosynthesis pathway. Recently, the crucial role of nutraceuticals in maintaining normal physiological function was established. Nutraceuticals play an important role in preventing several non-communicable diseases such as obesity, CVDs, cancer, diabetes, and reducing hyperlipidemia. Although the effect of nutraceuticals and herbal medicine on CVDs and dyslipidemia was previously investigated thoroughly, the effect of these natural products on HMGCoAR as one of the important enzymes involved in CVDs etiopathogenesis has not yet been investigated. Therefore, the major aim of this paper was to review the effects of nutraceuticals and medicinal plants on HMGCoAR. Results indicate that different types of natural foods, isolated nutrients, herbal products, and dietary supplements as nutraceuticals decrease the expression and activity of HMGCoAR. This review shows that medicinal plants and nutraceuticals could be used to decrease HMGCoAR activity as accessible and convenient and economical natural compounds to prevent dyslipidemia and CVDs.

Milk polar lipids modulate lipid metabolism, gut permeability, and systemic inflammation in high-fat-fed C57BL/6J ob/ob mice, a model of severe obesity

Dynamic interactions between lipid metabolism, gut permeability, and systemic inflammation remain unclear in the context of obesity. Milk polar lipids, lipids derived from the milk fat globule membrane, could positively affect the aforementioned obesity-related endpoints. This study aimed to test the hypotheses that milk polar lipids will reduce gut permeability, systemic inflammation, and liver lipid levels, and differentially affect the hepatic expression of genes associated with fatty acid synthesis and cholesterol regulation in preexisting obesity. We fed 3 groups of C57BL/6J ob/ob mice (n = 6 per group) for 2 wk: (1) a modified AIN-93G diet (CO) with 34% fat by energy; (2) CO with milk gangliosides (GG) at 0.2 g/kg of diet; and (3) CO with milk phospholipids (PL) at 10 g/kg of diet. The GG and PL were provided as semi-purified concentrates and replaced 2.0% and 7.2% of dietary fat by energy. The GG and PL did not affect total food intake, weight gain, fasting glucose, or gut permeability. The PL decreased liver mass and the mesenteric fat depot compared with the CO. The GG increased tight junction protein occludin in colon mucosa compared with the CO. The GG and PL decreased tight junction protein zonula occludens-1 in jejunum mucosa compared with the CO. Plasma endotoxin increased during the study but was unaffected by the treatments. Compared with the CO and GG, the PL increased plasma sphingomyelin and plasma IL-6. The GG and PL differentially regulated genes associated with lipid metabolism in the liver compared with the CO. Regarding general effects on lipid metabolism, the GG and PL decreased lipid levels in the liver and the mesenteric depot, and increased lipid levels in the plasma. Diet consumption decreased significantly when the ob/ob mice were kept in metabolic cages, which were not big enough and resulted in unwanted animal deaths. Future studies may keep this in mind and use better metabolic equipment for ob/ob mice. In conclusion, dietary milk polar lipids may have limited beneficial effects on gut barrier integrity, systemic inflammation, and lipid metabolism in the context of severe obesity.

Physiological parameters and productive performance of rabbit does and their offsprings with dietary supplementation of soy lecithin

Abstract: The objective of this work was to evaluate the effect of a dietary supplementation with soy lecithin (SL) on the productive performance and blood constituents of rabbit females and their offsprings. A total of 40 rabbits does were distributed into four treatments: control group, no dietary SL inclusion; and three groups with 0.5, 1.0, and 1.5% SL inclusion in the diets. The inclusion of 1.5% SL increased the count of blood cells and hemoglobin concentrations; 0.5-1.0% SL reduced the total cholesterol levels in the blood, as well as the low-density lipoprotein-cholesterol and the activities of the enzymes alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase, but increased the levels of total lipids, triglycerides, high-density lipoprotein-cholesterol, and the activities of the antioxidant enzymes. Supplementation with 1.0-1.5% SL resulted in higher milk production and heavier litters. Soy lecithin supplementation at 1% improves the physiological parameters and increases the milk production of rabbit does, also improving the performances of their offsprings.

Soybean amplifies the hypohomocysteinemic effect of betaine and improves its hypercholesterolemic effect

We examined whether soybean (SB) and soy protein isolate (SPI) can prevent the betaine-induced elevation of plasma cholesterol as well as maintain the betaine-induced reduction of plasma Hcy concentration. Rats were fed casein-, SB-, or SPI-based diet with or without betaine; SPI-based diet with betaine containing soybean fiber (SF) or soy lecithin (SL) or the combination of SF and SL. Plasma Hcy concentration was decreased by feeding betaine to rats fed the casein-, SB-, and SPI-based diets. Betaine-induced elevation of plasma cholesterol was decreased by feeding the SB-based diet compared with the casein-based diet, but was not decreased by feeding the SPI-based diet. In rats fed the SPI-based diet, the increased concentration of plasma cholesterol by betaine feeding was not prevented by independent addition of SL or SF, but was prevented by a combination of SL and SF, and was associated with increased fecal excretion of bile acids.

Regulation of hepatic lipid deposition by phospholipid in large yellow croaker

Dietary phospholipid (PL) supplementation has been shown to reduce lipid accumulation in the tissues of farmed fish; however, the mechanisms underlying this effect are largely unknown. Thus, the present study was conducted to evaluate the potential impacts of PL on hepatic lipid metabolism both in vivo and in vitro. For in vivo study, four experimental diets – low lipid and low PL diet, as control diet (LL-LP diet, containing 12 % lipid and 1·5 % PL), low-lipid and high-PL diet (containing 12 % lipid and 8 % PL), high-lipid and low-PL diet (HL-LP diet, containing 20 % lipid and 1·5 % PL) and high-lipid and high-PL diet (HL-HP diet, containing 20 % lipid and 8 % PL) – were randomly allocated to four groups of large yellow croaker (Larimichthys crocea) (three cages per group) with similar initial body weight (approximately 8 g). For in vitro study, primary hepatocytes isolated from large yellow croaker were incubated either with graded levels of phosphatidylcholine (PC) (0–250 μm) or small interfering RNA (siRNA) for CTP: choline phosphate cytidylyltranferase α (CCTα) (siRNA-CCTα). Results showed that survival was independent of dietary treatments (P>0·05). Weight gain and feed efficiency in the HL-HP group were significantly higher than in the LL-LP and HL-LP groups (P<0·05). High level of dietary PL could markedly reduce abnormal hepatic lipid accumulation induced by the HL-LP diet (P<0·05). Similarly, compared with the corresponding controls, a significant decrease/increase in lipid content was observed in primary hepatocytes incubated with PC/siRNA-CCTα (P<0·05). High level of dietary PL reversed the HL-LP diet-induced increased levels of mRNA of fatty acid uptake and lipid synthesis related genes (P<0·05). In addition, High level of dietary PL markedly down-regulated the transcript levels of fatty acid oxidation-related genes and enhanced the transcript levels of VLDL assembly-related genes regardless of dietary lipid levels (P<0·05). Compared with corresponding controls, primary hepatocytes treated with PC showed significantly higher mRNA expression of lipid synthesis and VLDL assembly-related genes and lower mRNA expression of fatty acid oxidation-related genes, with hepatocytes treated with siRNA-CCTα exhibiting the opposite trend (P<0·05). In summary, these results demonstrated that high level of dietary PL might reverse the HL-LP diet-induced abnormal lipid accumulation in the liver through inhibiting fatty acid uptake and lipid synthesis, together with promoting the lipid export at the transcriptional level. Lipid export-promoting effect of PC was confirmed by in vitro studies. The present study showed for the first time that PL or PC could influence various metabolic pathways to regulate hepatic lipid deposition in fish at least at the transcriptional level.

Abnormal histopathology, fat percent and hepatic apolipoprotein A I and apolipoprotein B100 mRNA expression in fatty liver hemorrhagic syndrome and their improvement by soybean lecithin

To investigate the etiopathogenesis of fatty liver hemorrhagic syndrome (FLHS) and the protective effects of soybean lecithin against FLHS in laying hens, 135 healthy 300-day-old Hyline laying hens were randomly divided into groups: control (group 1), diseased (group 2), and protected (group 3). Each group contained 45 layers with 3 replicates. The birds in these 3 groups were fed a control diet, a high-energy/low-protein (HELP) diet or the HELP diet supplemented with 3% soybean lecithin instead of maize. The fat percent in the liver was calculated. Histopathological changes in the liver were determined by staining, and the mRNA expression levels of apolipoproteinA I (apoA I) and apolipoprotein B100 (apoB100) in the liver were determined by RT-PCR. The results showed that the fat percent in the liver of group 2 was much higher (P < 0.01) than that of group 1 and group 2 on d 30 and 60. The histology of the liver in group 2 on d 30 and 60 displayed various degrees of liver lesions, while the hepatocytes showed a normal structure in group 3 with mild microvesicular steatosis in the liver cell on d 30 and 60. The mRNA expression levels of apoA I and apoB100 in the livers were variable throughout the experiment. The expression level of apoA I in group 2 significantly decreased on d 60 (P < 0.05); the expression level of apoB100 slightly increased on d 30 in group 2, while it sharply decreased on d 60. Compared to group 1, the expression level of apoB100 showed no significant difference in group 3 (P < 0.05). This study indicated that FLHS induced pathological changes and abnormal expression of apoA I and apoB100 in the livers of laying hens and that soybean lecithin alleviated these abnormal changes.

Dietary emulsifiers from milk and soybean differently impact adiposity and inflammation in association with modulation of colonic goblet cells in high-fat fed mice

SCOPE

Enhanced adiposity and metabolic inflammation are major features of obesity that could be impacted by dietary emulsifiers. We investigated in high-fat fed mice the effects of using a new polar lipid (PL) emulsifier from milk (MPL) instead of soybean lecithin (soybean PL [SPL]) on adipose tissue and intestinal mucosa function.

METHODS AND RESULTS

Four groups of C57BL6 mice received for 8 wks a low-fat (LF) diet or a high-fat diet devoid of PLs or an high-fat diet including MPL (high-fat-MPL) or SPL (high-fat-SPL). Compared with high-fat diet, high-fat-SPL diet increased white adipose tissue (WAT) mass (p < 0.05), with larger adipocytes (p < 0.05) and increased expression of tumor necrosis factor alpha, monochemoattractant protein-1, LPS-binding protein, and leptin (p < 0.05). This was not observed with high-fat-MPL diet despite similar dietary intakes and increased expression of fatty acid transport protein 4 and microsomal TG transfer protein, involved in lipid absorption, in upper intestine (p < 0.05). High-fat-MPL mice had a lower expression in WAT of cluster of differentiation 68, marker of macrophage infiltration, versus high-fat and high-fat-SPL mice (p < 0.05), and more goblet cells in the colon (p < 0.05).

CONCLUSIONS

Unlike SPL, MPL in the high-fat diet did not induce WAT hypertrophy and inflammation but increased colonic goblet cells. This supports further clinical exploration of different sources of dietary emulsifiers in the frame of obesity outbreak.

Essential phospholipids as a supportive adjunct in the management of patients with NAFLD

BACKGROUND AND STUDY AIMS

Treatment of nonalcoholic fatty liver (NAFLD) is important because NAFLD patients have a 1.7-fold increase in standardised age and gender matched mortality. Currently treatment is based on life style modification and managing comorbid associating disease. Other medications remain experimental. Essential phospholipid (EPL) is a nutrient for the liver, helping to maintain vitality of cell membranes where the vast majority of liver activities are regulated. We performed a randomised open label study to evaluate EPL as an adjuvant nutrient to the treatment of primary NAFLD or NAFLD with comorbid disease.

PATIENTS AND METHOD

Three groups of NAFLD patients were recruited: lone (n=113), diabetes mellitus type 2 (n=107) and mixed hyperlipidaemia (n=104). Diagnosis was established by excluding other chronic liver diseases. A standard diet and physical activity plan were advised to all patients. 1800mg of EPL a day was given for 24weeks, followed by 900mg for 48weeks.

RESULTS

Essential phospholipid EPL led to a significant improvement of symptoms and a mean reduction of ALT of 50.8IU and AST of 46.1IU per patient (p<0.01). Abdominal ultrasonography indicated normalisation in 4.6% and a shift from grade II to grade I in 24% of patients. Liver stiffness measurement indicated an improvement in 21.1%, with a mean reduction in the LSM of 3.1K Pascal/patient. Reducing the dosage after six months led to a limited relapse in 43.8-63.2% of patients, for lone and NAFLD with co-morbid conditions.

CONCLUSION

Essential phospholipid (EPL) as a nutritional supplement resulted in a significant improvement in clinical parameters and transaminases for all NAFLD patients. Ultrasound and LSM revealed modest improvement. There is a need for uninterrupted maintenance to avoid relapse.

Omega-3 phospholipids from fish suppress hepatic steatosis by integrated inhibition of biosynthetic pathways in dietary obese mice

Non-alcoholic fatty liver disease (NAFLD) accompanies obesity and insulin resistance. Recent meta-analysis suggested omega-3 polyunsaturated fatty acids DHA and EPA to decrease liver fat in NAFLD patients. Antiinflammatory, hypolipidemic, and insulin-sensitizing effects ofDHA/EPA depend on their lipid form, with marine phospholipids showing better efficacy than fish oils. We characterized the mechanisms underlying beneficial effects of DHA/EPA phospholipids, alone or combined with an antidiabetic drug, on hepatosteatosis. C57BL/6N mice were fed for 7 weeks an obesogenic high-fat diet (cHF) or cHF-based interventions: (i) cHF supplemented with phosphatidylcholine-rich concentrate from herring (replacing 10% of dietary lipids; PC), (ii) cHF containing rosiglitazone (10 mg/kg diet; R), or (iii) PC + R. Metabolic analyses, hepatic gene expression and lipidome profiling were performed. Results showed that PC and PC + R prevented cHlF-induced weight gain and glucose intolerance, while all interventions reduced abdominal fat and plasma triacylglycerols. PC and PC + R also lowered hepatic and plasma cholesterol and reduced hepatosteatosis. Microarray analysis revealed integrated downregulation of hepatic lipogenic and cholesterol biosynthesis pathways by PC, while R-induced lipogenesis was fully counteracted in PC + R Gene expression changes in PC and PC + R were associated with preferential enrichment of hepatic phosphatidylcholine and phosphatidylethanolamine fractions by DHA/EPA. The complex downregulation of hepatic lipogenic and cholesterol biosynthesis genes and the antisteatotic effects were unique to DHA/EPA-containing phospholipids, since they were absent in mice fed soy-derived phosphatidylcholine. Thus, inhibition of lipid and cholesterol biosynthesis associated with potent antisteatotic effects in the liver in response to DHA/EPA-containing phospholipids support their use in NAFLD prevention and treatment.

Combined effect of sesamin and soybean phospholipid on hepatic fatty acid metabolism in rats

We studied the combined effect of sesamin (1:1 mixture of sesamin and episesamine) and soybean phospholipid on lipid metabolism in rats. Male rats were fed diets supplemented with 0 or 2 g/kg sesamin, and containing 0 or 50 g/kg soybean phospholipid, for 19 days. Sesamin and soybean phospholipid decreased serum triacylglycerol concentrations and the combination of these compounds further decreased the parameter in an additive fashion. Soybean phospholipid but not sesamin reduced the hepatic concentration of triacylglycerol. The combination failed to cause a strong decrease in hepatic triacylglycerol concentration, presumably due to the up-regulation of Cd36 by sesamin. Combination of sesamin and soybean phospholipid decreased the activity and mRNA levels of hepatic lipogenic enzymes in an additive fashion. Sesamin strongly increased the parameters of hepatic fatty acid oxidation enzymes. Soybean phospholipid increased hepatic activity of 3-hydroxyacyl-CoA dehydrogenase although it failed to affect the activity of other enzymes involved in fatty acid oxidation. Sesamin strongly increased hepatic concentration of carnitine. Sesamin and soybean phospholipid combination further increased this parameter, accompanying a parallel increase in mRNA expression of carnitine transporter. These changes can account for the strong decrease in serum triacylglycerol in rats fed a diet containing both sesamin and soybean phospholipid.

Fat lowers fat: purified phospholipids as emerging therapies for dyslipidemia

Dyslipidemia is a major coronary heart disease (CHD) risk factor. In spite of the proven efficacy of statin drugs in reducing CHD burden, there is still much room for the discovery of novel therapeutic agents to address the considerable residual cardiovascular risk that remains after treatment with currently available medications. In particular, there is an urgent demand for drugs capable of boosting the concentration and/or function of high-density lipoprotein (HDL) and apolipoprotein A-I (apo A-I), thereby promoting reverse cholesterol transport. Phospholipids are naturally occurring fats that play indispensible role in human health via their structural, energy storage, signal transduction and metabolic functions. Supplementation with either purified or mixed preparations of bioactive phospholipids has been reported to ameliorate a range of nutritional and cardiovascular disorders. Moreover, several lines of evidence have supported the efficacy of dietary phospholipids in reducing serum and hepatic contents of cholesterol and triglycerides, while increasing HDL-C and apo A-I levels. These beneficial effects of phospholipids could be attributed to their ability in reducing intestinal cholesterol absorption, enhancing biliary cholesterol excretion and modulating the expression and activity of transcriptional factors and enzymes that are involved in lipoprotein metabolism. Given their extreme safety and biocompatibility, dietary supplementation with phospholipid preparations, in particular phosphatidylinositol, appears as a novel and effective strategy that could be used as an alternative or adjunctive therapy to the current medications. The present review outlines the in-vitro, in-vivo and clinical findings on the anti-dyslipidemic effects of three most abundant phospholipids in the human body and diet namely phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol.

Marine omega-3 phospholipids: metabolism and biological activities

The biological activities of omega-3 fatty acids (n-3 FAs) have been under extensive study for several decades. However, not much attention has been paid to differences of dietary forms, such as triglycerides (TGs) versus ethyl esters or phospholipids (PLs). New innovative marine raw materials, like krill and fish by-products, present n-3 FAs mainly in the PL form. With their increasing availability, new evidence has emerged on n-3 PL biological activities and differences to n-3 TGs. In this review, we describe the recently discovered nutritional properties of n-3 PLs on different parameters of metabolic syndrome and highlight their different metabolic bioavailability in comparison to other dietary forms of n-3 FAs.

Influence of chronic stress on the compositions of hepatic cholesterol and triglyceride in male Wistar rats fed a high fat diet

AIM

  We determined the influence of chronic stress (CS) on the compositions of hepatic cholesterol and triglyceride (TG) in rats fed a high fat diet (HFD).

METHODS

  Male Wistar rats were fed either a standard diet or a HFD and half of the HFD fed rats were given CS (electric foot shock assisted with noise) for 8 weeks.

RESULTS

  Compared with the control group, the levels of hepatic total cholesterol (TC) and TG were significantly elevated in the HFD and HFD with chronic stress (HFD+CS) groups, and the more severe elevations of them were found in the HFD group. Inversely, the more severe elevations of hepatic water-soluble parts of TC and TG were found in the HFD+CS group, as the elevations of low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol in liver and serum, tumor necrosis factor-α, interleukin-1β and malondialdehyde in liver. Meanwhile, downregulated mRNA expressions of hepatic liver X receptor-α (LXR-α) and peroxisome proliferator-activated receptor-γ (PPAR-γ) were also more severe in the HFD+CS group.

CONCLUSION

  CS can aggravate the high levels of water-soluble compositions of hepatic TC and TG induced by HFD as it aggravates hepatic inflammation and oxidative stress; in spite of that, however, it cannot further promote hepatic lipidosis. This is consistent with the downregulated mRNA expressions of LXR-α and PPAR-γ.

P-glycoprotein and its inhibition in tumors by phytochemicals derived from Chinese herbs

P-glycoprotein belongs to the family of ATP-binding cassette (ABC) transporters. It functions in cellular detoxification, pumping a wide range of xenobiotic compounds, including anticancer drugs out of the cell. In cancerous cells, P-glycoprotein confers resistance to a broad spectrum of anticancer agents, a phenomenon termed multidrug resistance. An attractive strategy for overcoming multidrug resistance is to block the transport function of P-glycoprotein and thus increase intracellular concentrations of anticancer drugs to lethal levels. Efforts to identify P-glycoprotein inhibitors have led to numerous candidates, none of which have passed clinical trials with cancer patients due to their high toxicity. The search for naturally inhibitory products from traditional Chinese medicine may be more promising because natural products are frequently less toxic than chemically synthesized substances. In this review, we give an overview of molecular and clinical aspects of P-glycoprotein and multidrug resistance in the context of cancer as well as Chinese herbs and phytochemicals showing inhibitory activity towards P-glycoprotein.

Ripened dairy products differentially affect hepatic lipid content and adipose tissue oxidative stress markers in obese and type 2 diabetic mice

Growing evidence suggests that the consumption of dairy products may contribute to a reduced incidence of cardiovascular risk factors, such as obesity, dyslipidemia, and type 2 diabetes. The fatty acid composition in milk fat, the duration of ripening, and the complexity of the food matrices are important factors that may interfere with the physiological impact. In this study, we treated genetic obese and type 2 diabetic mice (db/db) for 4 weeks with different dairy (cheese-based) products, differing by the duration of ripening (0, 15, or 35 days). We found that 35 days ripened product significantly improved glucose tolerance, an effect associated with a decreased adipose tissue lipid peroxide markers (TBARS and NAPDH-oxidase mRNA expression), without affecting body weight, food intake, and fat mass. Both fermented matrices significantly decreased the hepatic lipid content, without modifying plasma triglycerides or plasma total cholesterol. These data suggest that dairy products issued from longer ripening positively impact glucose tolerance, hepatic steatosis, and adipose tissue oxidative stress. Further investigations are warranted to decipher the interactions between milk products fermentation, lipids, and host metabolism.

Influence of soy lecithin administration on hypercholesterolemia

Recent studies suggest that lecithin-rich diet can modify cholesterol homeostasis and hepatic lipoprotein metabolism. Considering the phytotherapeutic impact of lecithin, this work hypothesizes that lecithin administration in hypercholesterolemic patients may reduce cholesterol concentrations by increasing biliary secretion. Total cholesterol and LDL were evaluated after soy lecithin administration in hypercholesterolemic patients. One soy lecithin capsule (500 mg/RP-Sherer) was administrated daily. One-two months before the treatment beginning, blood samples were collected for total lipids and cholesterol fractions analysis. The results showed a reduction of 40.66% and 42.00% in total cholesterol and of 42.05% and 56.15% in LDL cholesterol after treatment for one and two months, respectively. A significant reduction in total cholesterol and LDL-cholesterol concentrations was observed during the first month of treatment, suggesting that the administration of soy lecithin daily may be used as a supplemental treatment in hypercholesterolemia.

Soy lecithin supplementation alters macrophage phagocytosis and lymphocyte response to concanavalin A: a study in alloxan-induced diabetic rats

Dietary soy lecithin supplementation decreases hyperlipidemia and influences lipid metabolism. Although this product is used by diabetic patients, there are no data about the effect of soy lecithin supplementation on the immune system. The addition of phosphatidylcholine, the main component of lecithin, to a culture of lymphocytes has been reported to alter their function. If phosphatidylcholine changes lymphocyte functions in vitro as previously shown, then it could also affect immune cells in vivo. In the present study, the effect of dietary soy lecithin on macrophage phagocytic capacity and on lymphocyte number in response to concanavalin A (ConA) stimulation was investigated in non-diabetic and alloxan-induced diabetic rats. Supplementation was carried out daily with 2 g kg(-1) b.w. lecithin during 7 days. After that, blood was drawn from fasting rats and peritoneal macrophages and mesenteric lymph node lymphocytes were collected to determine the phospholipid content. Plasma triacylglycerol (TAG), total and HDL cholesterol and glucose levels were also determined. Lymphocytes were stimulated by ConA. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) dye reduction method and flow cytometry were employed to evaluate lymphocyte metabolism and cell number, respectively. Soy lecithin supplementation significantly increased both macrophage phagocytic capacity (+29%) in non-diabetic rats and the lymphocyte number in diabetic rats (+92%). It is unlikely that plasma lipid levels indirectly affect immune cells, since plasma cholesterol, TAG, or phospholipid content was not modified by lecithin supplementation. In conclusion, lymphocyte and macrophage function were altered by lecithin supplementation, indicating an immunomodulatory effect of phosphatidylcholine.

Dietary phospholipids, hepatic lipid metabolism and cardiovascular disease

PURPOSE OF REVIEW

An increasing number of studies in experimental animals suggest that dietary phospholipids might be of benefit in the treatment of fatty liver disease. This raises the possibility that synthetic or naturally occurring phospholipid isolates could be used as hepatoprotective nutraceuticals or functional foods. The aim of the present article is to review published data describing the beneficial effects of dietary phospholipids on hepatic lipid metabolism and their potential to affect atherosclerosis and cardiovascular disease.

RECENT FINDINGS

Consistent results have been obtained supporting the concept that phospholipid from various sources (i.e., soybean, safflower, egg and fish roe) can reduce liver lipid levels. The primary site of action for this effect appears to be in the intestinal lumen, where dietary phospholipids are able to interfere with neutral sterol absorption. Results have also been obtained suggesting that dietary phospholipids can stimulate bile acid and cholesterol secretion. Additional work suggests that dietary phospholipids can have a beneficial effect on plasma lipid and lipoprotein levels.

SUMMARY

The concept of using naturally occurring compounds such as phospholipid to treat or prevent hepatic steatosis is very attractive. Controlled human trials are, however, required to verify the efficacy of this approach. It is also important that additional research be conducted to determine the extent to which certain phospholipids have the ability to increase plasma HDL levels and potentially affect the onset or development of cardiovascular disease.

Injection lipolysis for reduction of saddlebag trochanteric bulges--half-side controlled pilot study

BACKGROUND

Phosphatidylcholine, a lecithin extracted from soybeans can reduce serum cholesterol to some extent. Intravenous use may prevent fat embolism in polytrauma patients. When injected intralesionally in a formulation containing also deoxycholate and ethanol it is supposed to act as "fat burner" to reduce undesired fat deposits; there is little evidence-based scientific support for this indication.

OBJECTIVE

To evaluate the capability of phosphatidylcholine + deoxycholate + ethanol (PPC/DC/E) to reduce body fat with a half-side pilot study for the reduction of saddlebag trochanteric bulges.

METHODS

PPC/DC/E was injected into the right posterior trochanteric areas three times at weeks 0, 3 and 6. Treatment areas and the same regions of the contralateral side as a control were evaluated by sonography. Tape measurements were taken and the thickness of the subcutaneous adipose tissue (SAT) was measured with an optical device (Lipometer) at baseline and at week 8 and week 20 (2 and 14 weeks after completing therapy).

RESULTS

In this half-side trial, no significant reduction of subcutaneous fat was achieved after three treatments with PPC/DC/E when compared to the untreated side.Transient inflammatory reactions occurred in all patients.

LIMITATIONS

Only the commercially available formulation containing the three components was tested.

CONCLUSION

The off-label use of PPC/DC/E as a "fat burner" did not produce measurable reduction of undesired trochanteric fat deposits.

Effect of soybean phospholipids on canthaxanthin lipoproteins transport, digestibility, and deposition in rainbow trout (Oncorhynchus mykiss) muscle

This study was designed to assess the effect of dietary soybean phospholipids on canthaxanthin transport by serum lipoproteins and canthaxanthin muscle deposition in trout. Three groups of 12 immature trout in triplicate with a mean body weight of 130 g were fed with three experimental diets containing (1) canthaxanthin plus lecithin plus fish oil, (2) canthaxanthin plus lecithin, and (3) canthaxanthin alone, for 12 days. The two major lipoprotein classes in rainbow trout are high-density lipoproteins, which transport principally carotenoids present in the serum, and low-density lipoproteins, which are responsible for the transport of cholesterol, both independently of the administered diet. In addition, very low density lipoproteins are responsible for triglyceride transport in serum. Nevertheless, the amount of canthaxanthin in the serum increased when carotenoid was associated with phospholipids plus fish oil. When canthaxanthin is transported by lecithin plus fish oil, the amount of phospholipids, cantaxanthin, and cholesterol deposited in muscle increased but not significantly. The highest apparent canthaxanthin digestibility coefficient was obtained when canthaxanthin was carried by lecithin plus fish oil. The administration of canthaxanthin carried by phospholipids improved its accumulation in the muscle of rainbow trout. This accumulation could be enhanced if the time of administration of canthaxanthin is increased.

Fat tissue after lipolysis of lipomas: A histopathological and immunohistochemical study

BACKGROUND

Injections with Lipostabil, a phosphatidylcholine (PDC) containing substance, have become a popular technique to treat localized fat accumulation and lipomas for aesthetic reasons. Despite its frequent use, the mechanism of action of PDC and histological changes of treated fat tissue still remain unclear. To investigate the histological changes of lipomas after treatment with PDC.

METHODS

In all, fourteen lipomas (n = 14) in five patients presenting with multiple lipomas were treated with intralesional injections of PDC (Lipostabil, Nettermann, Germany). Histological changes with immunohistochemical analysis of the inflammatory process were evaluated 4, 10, 24, 48 h, 10 days, 30 days and 60 days after lipolysis.

RESULTS

Between 4 and 48 h after injection, histology shows a lobular neutrophilic infiltrate with partially destroyed fat cells. At day 10 the inflammatory process is accompanied by an infiltration of T-lymphocytes. After 60 days formation of macrophages with foam cells are visible, accompanied by thickened septa and capsula.

CONCLUSION

Lipolysis with PDC results in a distinct inflammatory reaction of affected fat tissue, similar to factitial panniculitis. Early destruction of fat cells may suggest the involvement of detergent or osmotic mechanisms in the process.

Dietary lecithin protects against cholestatic liver disease in cholic acid-fed Abcb4- deficient mice

Mutations in multidrug resistance 3 gene (MDR3 or ABCB4) underlie progressive familial intrahepatic cholestasis type 3 (PFIC3), a severe pediatric liver disease progressing to cirrhosis. Abcb4-/- mice exhibit slowly developing hepatic lesions that can be accelerated by feeding a cholic acid (CA)-supplemented diet. We investigated the beneficial effects of a soybean lecithin (L)-supplemented diet in this model of liver disease. Abcb4-/- mice and wild-type (WT) controls were divided in four groups by the diet they were fed: control (C) diet, L-supplemented diet, CA-supplemented diet, and L- and CA-supplemented (L+CA) diet. After 2 wk on these regimens, liver enzymes and bilirubin were measured in serum with bile flow, total bile acids, and cholesterol (CHOL) and phospholipid (PL) concentrations in bile. Ductular hyperplasia, portal fibroblastic cell proliferation, myofibroblast activation, and hepatic fibrosis were quantified on liver sections. Abcb4-/- mice fed the C diet exhibited mild liver damage. CA produced very high elevations of serum liver enzymes and bilirubin with significant bile duct proliferation, peribiliary fibroblast activation, and fibrosis. The L-supplemented diet dramatically mitigated the hepatic damage in CA-supplemented diet animals. We conclude that L is protective against liver disease in Abcb4-/- mice and suggest that it could offer potential benefit in PFIC3.

Histopathologic Changes After Intralesional Application of Phosphatidylcholine for Lipoma Reduction

Phosphatidylcholine, a lecithin extracted from soy beans, is able to lower serum cholesterol to some extent. When applied intralesionally within fat tissues, it is supposed to act as a "fat burner" and reduce undesired fat deposits. We applied intralesionally phosphatidylcholine within a lipoma of a young patient. To evaluate the volume of the lipoma sonographic imaging was performed before treatment and one month after the third application. Only a partial reduction of the lipoma could be achieved, and increased echographic density could be observed after the third intralesional application of phosphatidylcholine. Surgical excision was performed. Histologic examination showed focal fibrosis, inflammatory reaction with granulomatous features, and presence of pseudomembranous degeneration of fat tissue. Off-label intralesional use of phosphatidylcholine as "fat burner" for the reduction of aesthetically disturbing lipomas should be considered only on a case-to-case basis after careful consideration of possible undesired effects similar to those described in our patient.

Effect of 18∶1n−9, 20∶5n−3, and 22∶6n−3 on lipid accumulation and secretion by atlantic salmon hepatocytes

We have studied the effects of dietary FA on the accumulation and secretion of [3H]glycerolipids by salmon hepatocytes in culture. Atlantic salmon were fed diets supplemented with either 100% soybean oil (SO) or 100% fish oil (FO), and grew from an initial weight of 113 +/- 5 g to a final weight of 338 +/- 19 g. Hepatocytes were isolated from both dietary groups and incubated with [3H]glycerol in an FA-free medium; a medium supplemented with 0.75 mM of one of three FA-18:1 n-9, 20:5n-3, or 22:6n-3--or a medium supplemented with 0.75 mM of the sulfur-substituted FA analog tetradecylthioacetic acid (TTA), which cannot undergo beta-oxidation. Incubations were allowed to proceed for 1, 2, 6, or 24 h. The rate of the secretion of radioactive glycerolipids with no FA added was 36% lower from hepatocytes isolated from fish fed the FO diet than it was from hepatocytes isolated from fish fed the SO diet. Hepatocytes incubated with 18:1 n-9 secreted more [3H]TAG than when incubated with no FA, whereas hepatocytes incubated with 20:5n-3 or TTA secreted less labeled TAG than when incubated with no FA. This observation was independent of the feeding group. Hepatocytes incubated with 22:6n-3 secreted the highest amounts of total [3H]glycerolipids compared with the other treatments, owing to increased secretion of phospholipids and mono- and diacylglycerols (MDG). In contrast, the same amounts of [3H]TAG were secreted from these cells as from cells incubated in an FA-free medium. The lipid-lowering effect of FO is thus independent of 22:6n-3, showing that 20:5n-3 is the FA that is responsible for the lipid-lowering effect. The ratio of TAG to MDG in lipids secreted from hepatocytes to which 20:5n-3 or TTA had been added was lower than that in lipids secreted from hepatocytes incubated with 18:1 n-9 or 22:6n-3, suggesting that the last step in TAG synthesis was inhibited. Morphometric measurements revealed that hepatocytes incubated with 20:5n-3 accumulated significantly more cellular lipid than cells treated with 18:1n-9, 22:6n-3, TTA, or no treatment. The area occupied by mitochondria was also greater in these cells. The present study shows that dietary FO reduces TAG secretion from salmon hepatocytes and that 20:5n-3 mediates this effect.

Phosphatidylcholine-enriched diet prevents gallstone formation in mice susceptible to cholelithiasis

Cholesterol gallstones affect approximately 10-15% of the adult population in North America. Phosphatidylcholine (PC) is considered to be the main cholesterol solubilizer in bile. This study examined the effect of a PC-enriched diet on gallstone incidence in mice susceptible to cholelithiasis. The result obtained showed that the feeding of a lithogenic (LG) diet for 4 weeks or 8 weeks resulted in cholesterol gallstone incidences of 47% and 89%, respectively. These gallstone incidences were either reduced or prevented when the LG diet was enriched with 2% or 6% PC, respectively. The cholesterol saturation index (CSI) was reduced only in mice fed with LG + 6% PC diet as compared with mice fed the LG diet alone. However, in all groups, the CSI was significantly higher than in mice fed Purina chow diet. The biliary anionic polypeptide fraction (APF) was significantly increased in mice fed the LG + 2% PC diet and was reduced in those fed with LG + 6% PC diet. In conclusion, prevention or delay of gallstone formation was not due to a consistent effect on biliary lipid composition, suggesting a direct effect of PC on cholesterol solubilization and/or the effect of an additional nonlipid biliary component such as APF.