Intakes and major dietary sources of cholesterol and phytosterols in the British diet

Cholesterol intakes in Britain have been re-estimated by analysing Total Diet samples taken in 1991 and from 1993 National Food Survey records. The Total Diet samples contained only 284 mg/day compared with 319 mg/day in 1987 and 337 mg/day in 1981, while the National Food Survey showed intakes had fallen to 238 mg/day from 259 mg/day in 1990 and 405 mg/day in 1970-75. More details of the intakes by adults in 1986/87 are given, and compared with the results from the other methods. Daily intakes of eight phytosterols were also estimated, the main ones being β-sitosterol, campesterol, stigmasterol and 57-stigmastenol whose intakes were 104, 49, 10 and 4 mg/day, respectively, in 1991. These intakes had increased since 1981, reflecting the rising consumption of vegetable oils.     

鸡蛋参的化学成分研究

从鸡蛋参Ｃｏｄｏｎｏｐｓｉｓ ｃｏｎｖｏｌｖｕｌａｃｅａ的干燥块根中分行９个化合物,经理化性质和光谱分析分别鉴定为：（２Ｅ）－２－乙基－二十九－２－烯醛（Ⅰ）,１,２－丙二醇双十七酸酯（Ⅱ）,豆甾烷醇（Ⅲ）,α－菠甾醇（Ⅳ）,α菠甾酮（Ⅴ）,二十五烷（Ⅵ）,木栓酮（Ⅶ）,β－香树脂乙酸酯（Ⅷ）和羽扇豆醇乙酯（Ⅸ）,其中Ⅰ为一新化合物,Ⅱ,Ⅲ,Ⅷ和Ⅸ为首次从党参属植物中分得。     

Plant sterols in vegetables and fruits commonly consumed in Sweden

Summary Plant sterols are known to have serum cholesterol lowering effects. A high dietary intake might therefore have a positive impact on health. All food items of vegetable origin contain some amount of plant sterols. The aim of this study was to analyse the plant sterol content of vegetables and fruits commonly consumed in Sweden, and to compare fresh and cooked samples of the same items. Altogether 20 different vegetables and 14 fruits were analysed. All vegetables and fruits were purchased in two shops in the city of Gothenburg, Sweden. Lyophilization was performed within one month of the items being purchased. The samples were frozen at −20 (C and analysed within six months, with a GLC method after acid hydrolysis, alkaline hydrolysis and silylation with tri-methylsilylether. The acid hydrolysis was done in order to detect the fraction of glycosylated plant sterols, which are split during boiling with HCl. The median plant sterol content of vegetables was 14 (3.8–50) mg/100 g edible portion. The highest concentrations were found in broccoli, Brussels sprouts, cauliflower and olives. The median plant sterol content of fruits was 16 (3–44) mg/100 g edible portion. The highest concentrations were found in oranges and passion fruits. The plant sterol concentrations were thus low in vegetables and fruits commonly consumed in Sweden. A serum cholesterol lowering effect attributed to the plant sterols in vegetables and fruits would therefore be of limited significance. Received: 25 September 1998, Accepted: 10 February 1999     

红花锦鸡儿化学成分的研究

 目的 研究红花锦鸡儿（Caragana rosea）的化学成分。方法 用色谱技术进行分离纯化，根据理化性质和光谱分析对化合物的结构进行鉴定。结果 从红花锦鸡儿茎的95%乙醇提取物的氯仿萃取物中分离得到5个甾醇化合物和1个三萜化合物，其结构分别鉴定为7α-羟基-β-谷甾醇(1)、7β-羟基-β-谷甾醇(2)、5α-豆甾烷-3β,6α-二醇(3)、β-谷甾醇(4)、胡萝卜苷(5)和齐墩果酸(6)。结论 所有化合物均为首次从红花锦鸡儿中分离得到。     

Hypolipidaemic activity of methanol extract of Aleurites moluccana

The lipid-lowering action of the leaves of the Aleurites moluccana methanol extract was studied in Triton W-1339 and high-fat-diet fed rats. The serum lipids (total cholesterol, LDL- and HDL-cholesterol and triglycerides) and body weight were found to be lowered by A. moluccana (300 mg/kg, b.w.) in rats with Triton-induced hypercholesterolaemia and on a hyperlipaemic diet. The results suggest that the lipid lowering action of this natural product is mediated through inhibition of hepatic cholesterol biosynthesis and reduction of lipid absorption in the intestine.     

Protective role of Hemidesmus indicus R. Br. root extract against Salmonella typhimurium-induced cytotoxicity in Int 407 cell line

The present investigation deals with the effect of the chloroform fraction composed of sterols and fatty acids isolated from Hemidesmus indicus root extract (CHI) on Salmonella enterica serovar Typhimurium (S. typhimurium)-induced cytotoxicity in a human intestinal epithelial cell line (Int 407). The optimum dose was fixed as 100 microg/mL for CHI against S. typhimurium, which was quite safe for Int 407 cells as the CD(50) concentration (50% cell death) of CHI was determined to be 500 microg/mL in the Int 407 cell line. CHI-treated S. typhimurium were 10-fold less cytotoxic and 40% less adherent to host cells than wild-type. Treatment of CHI significantly abrogated the invasion ability to 10- to 15-fold in S. typhimurium. The cells infected with CHI-treated S. typhimurium had a comparable viability to uninfected cells in the epithelial cell detachment assay. Immunofluorescence showed the CHI-treated bacteria were unhealthy and shrunken rods in comparison with the wild-type bacteria; those were firmly attached and invaded to deceased and hypertrophoid Int 407 cells. Transmission electron micrographs of Int 407 cells infected with wild bacteria showed a coat of adherent and invaded bacteria completely occupying the cytoplasm with characteristic Salmonella-containing vacuoles (SCV). Both necrotic and apoptotic type of cell death were observed in cells infected with wild-type bacteria, whereas most of the cells infected with treated bacteria were normal in morphology and a few had invaded bacteria, but the typical proliferated SCV was not observed in cells infected with CHI-treated S. typhimurium. In summary, the sterols and fatty acids present in CHI may be capable of taming S. typhimurium by suppressing its cytotoxic activity in an intestinal epithelial cell line.     

Evaluating the safety of phytosterols removed perilla seed oil-based lipid emulsion

ABSTRACT

Objectives: The aim of this study was to ascertain the potential toxicity of perilla seed oil-based lipid emulsion (POLE) caused by phytosterols and confirm the efficacy of the technique for removing phytosterols from perilla seed oil, and evaluate the safety of a low phytosterol POLE in a long-term tolerance study in dogs.

Methods: A comparison between a soybean oil lipid emulsion (Intralipid group A) and POLE with high (group B) versus low (group C) levels of phytosterols was made with regard to their effects on the general condition, hematological and biochemical parameters, urinalysis and histopathological changes in nine dogs receiving daily infusions for four weeks at dosage levels of 6, 6, 9 g fat /kg.

Results: Dogs in group A and group C remained in good condition and gained weight during the infusion period and no diarrhea or gastrointestinal bleeding occurred. Only a moderate degree of anemia was observed, the biochemical parameters changed only slightly and returned to normal after treatment had ceased. However, the dogs in group B exhibited significant symptoms of ‘fat overload syndrome’. Vomiting, diarrhoea and blood in the faeces were observed. Moreover, triglyceridemia, cholesteremia, and dark urine as well as microscopic signs of liver and gastrointestinal tract damage and generalized jaundice were clearly seen.

Conclusions: Phytosterols promote ‘fat overload syndrome’ in long-term tolerance studies of POLE in dogs by producing cholestatic liver injury and interfering with fat metabolism. And the toxicity of POLE was reduced by removing phytosterols.     

Phytosterols Synergize With Endotoxin to Augment Inflammation in Kupffer Cells but Alone Have Limited Direct Effect on Hepatocytes

Introduction: Phytosterols are implicated in the development of parenteral nutrition–associated liver disease. A newly proposed mechanism for phytosterol‐mediated parenteral nutrition–associated liver disease is through phytosterol‐facilitated hepatic proinflammatory cytokine release following exposure to intestinally derived bacteria. Whether the proinflammatory effects are liver cell specific is not known. Aim: To determine if phytosterols cause inflammation in hepatocytes or Kupffer cells independently or require costimulation by lipopolysaccharide (LPS). Methods: In an in vivo study, neonatal piglets on parenteral nutrition for 11 days received an 8‐hour infusion of LPS. In the in vitro studies, neonatal piglet Kupffer cells and hepatocytes were treated with media, media + 1% soy oil, or media + 1% soy oil + 100µM phytosterols. After 24‐hour incubation, cells were treated with farnesoid X receptor (FXR) agonist obeticholic acid or liver X receptor (LXR) agonist GW3965 and challenged with LPS or interleukin 1β. Results: LPS administration in piglets led to transient increases in proinflammatory cytokines and suppression of the transporters bile salt export pump and ATP‐binding cassette transporter G5. In hepatocytes, phytosterols did not activate inflammation. Phytosterol treatment alone did not activate inflammation in Kupffer cells but, combined with LPS, synergistically increased interleukin 1β production. FXR and LXR agonists increased transporter expression in hepatocytes. GW3965 suppressed proinflammatory cytokine production in Kupffer cells, but obeticholic acid did not. Conclusions: LPS suppresses transporters that control bile acid and phytosterol clearance. Phytosterols alone do not cause inflammatory response. However, with costimulation by LPS, phytosterols synergistically maximize the inflammatory response in Kupffer cells.     

In vitro inhibition of adenosine deaminase by a group of steroid and Triterpenoid compounds

The effects of several sapogenins and saponins of the steroid and triterpenoid classes, as well as of a few common phytosterols, have been tested for their inhibitory action towards adenosine deaminase (ADA). It was found that the acidic sapogenins strongly inhibit the enzyme. The mean inhibitory concentration (IC₅₀) was in the range 10^?3 to 10^?2 mg/mL, while the inhibitor constants (K_i) have been estimated as about 10^?6 M. In contrast to this finding is the complete absence of any influence on the enzyme of the neutral sapo(ge)nins and the phytosterols. It is suggested that ADA is a worthwhile therapeutic target and that the (acidic) sapogenins, which are regular constituents of many medicinal plant species, presumably contribute their activity through an interaction with this enzyme.