Loading...
(1/8527) Dietary intake and practices in the Hong Kong Chinese population.

OBJECTIVES: To examine dietary intake and practices of the adult Hong Kong Chinese population to provide a basis for future public health recommendations with regard to prevention of certain chronic diseases such as cardiovascular disease, hypertension, and osteoporosis. PARTICIPANTS: Age and sex stratified random sample of the Hong Kong Chinese population aged 25 to 74 years (500 men, 510 women). METHOD: A food frequency method over a one week period was used for nutrient quantification, and a separate questionnaire was used for assessment of dietary habits. Information was obtained by interview. RESULTS: Men had higher intakes of energy and higher nutrient density of vitamin D, monounsaturated fatty acids and cholesterol, but lower nutrient density of protein, many vitamins, calcium, iron, copper, and polyunsaturated fatty acids. There was an age related decrease in energy intake and other nutrients except for vitamin C, sodium, potassium, and percentage of total calorie from carbohydrate, which all increased with age. Approximately 50% of the population had a cholesterol intake of < or = 300 mg; 60% had a fat intake < or = 30% of total energy; and 85% had a percentage of energy from saturated fats < or = 10%; criteria considered desirable for cardiovascular health. Seventy eight per cent of the population had sodium intake values in the range shown to be associated with the age related rise in blood pressure with age. Mean calcium intake was lower than the FAO/WHO recommendations. The awareness of the value of wholemeal bread and polyunsaturated fat spreads was lower in this population compared with that in Australia. There was a marked difference in types of cooking oil compared with Singaporeans, the latter using more coconut/palm/mixed vegetable oils. CONCLUSION: Although the current intake pattern for cardiovascular health for fat, saturated fatty acid, and cholesterol fall within the recommended range for over 50% of the population, follow up surveys to monitor the pattern would be needed. Decreasing salt consumption, increasing calcium intake, and increasing the awareness of the health value of fibre may all be beneficial in the context of chronic disease prevention.  (+info)

(2/8527) Dietary control of triglyceride and phospholipid synthesis in rat liver slices.

1. The effect of dietary manipulation on the synthesis of triglycerides and phospholipids was investigated by determining the incorporation of labeled long-chain fatty acid or glycerol into these lipids in liver slices derived from normally fed, fasted, and fat-free refed rats. 2. Triglyceride synthesis was affected markedly by the dietary regime of the animal; the lowest rates were measured with fasted rats, and the highest ones with fat-free refed rats. 3. In contrast to triglyceride synthesis, phospholipid synthesis occured at virtually constant rates regardless of the dietary conditions. 4. Addition of large amounts of fatty acid to the incubation mixture resulted in a marked stimulation of triglyceride synthesis, whereas phospholipid synthesis was affected to a much smaller extent. 5. These results indicate that the synthesis of triglycerides and that of phospholipids are controlled independently, and that the availability of fatty acid in the cell contributes to the control of triglyceride synthesis.  (+info)

(3/8527) Diet and risk of ethanol-induced hepatotoxicity: carbohydrate-fat relationships in rats.

Nutritional status is a primary factor in the effects of xenobiotics and may be an important consideration in development of safety standards and assessment of risk. One important xenobiotic consumed daily by millions of people worldwide is alcohol. Some adverse effects of ethanol, such as alcohol liver disease, have been linked to diet. For example, ethanol-induced hepatotoxicity in animal models requires diets that have a high percentage of the total calories as unsaturated fat. However, little attention has been given to the role of carbohydrates (or carbohydrate to fat ratio) in the effects of this important xenobiotic on liver injury. In the present study, adult male Sprague-Dawley rats (8-10/group) were infused (intragastrically) diets high in unsaturated fat (25 or 45% total calories), sufficient protein (16%) and ethanol (38%) in the presence or absence of adequate carbohydrate (21 or 2.5%) for 42-55 days (d). Animals infused ethanol-containing diets adequate in carbohydrate developed steatosis, but had no other signs of hepatic pathology. However, rats infused with the carbohydrate-deficient diet had a 4-fold increase in serum ALT levels (p < 0.05), an unexpectedly high (34-fold) induction of hepatic microsomal CYP2E1 apoprotein (p < 0.001), and focal necrosis. The strong positive association between low dietary carbohydrate, enhanced CYP2E1 induction and hepatic necrosis suggests that in the presence of low carbohydrate intake, ethanol induction of CYP2E1 is enhanced to levels sufficient to cause necrosis, possibly through reactive oxygen species and other free radicals generated by CYP2E1 metabolism of ethanol and unsaturated fatty acids.  (+info)

(4/8527) Comparative hypocholesterolemic effects of five animal oils in cholesterol-fed rats.

The hypocholesterolemic efficacy of various animal oils was compared in rats given a cholesterol-enriched diet. After acclimatization for one week, male F344 DuCrj rats (8 weeks of age) that had been fed with a conventional diet were assigned to diets containing 5% of oil from emu (Dromaius), Japanese Sika deer (Cervus nippon yesoensis, Heude), sardine, beef tallow, or lard with 0.5% cholesterol for 6 weeks. After this feeding period, the concentrations of serum total cholesterol and of very-low-density lipoprotein + intermediate-density lipoprotein + low-density lipoprotein-cholesterol in the sardine oil group were significantly lower than those in the other groups. The serum high-density lipoprotein-cholesterol concentration in the Japanese Sika deer oil group was significantly higher than that in the other groups. The atherosclerotic index and liver cholesterol concentration in the sardine oil and Japanese Sika deer oil groups were significantly lower than those in the other groups. The fecal cholesterol excretion by the Japanese Sika deer oil group was significantly higher than that of the other groups, except for the sardine oil group, and the fecal bile acid excretion by the sardine oil group was significantly higher than that of the other groups, except for the lard group. These results suggest that Japanese Sika deer oil reduced the atherosclerotic index and liver cholesterol concentration in the presence of excess cholesterol in the diet as well as sardine oil did by increasing the excretion of cholesterol from the intestines of rats.  (+info)

(5/8527) Manipulation of the type of fat consumed by growing pigs affects plasma and mononuclear cell fatty acid compositions and lymphocyte and phagocyte functions.

To investigate the immunological effect of feeding pigs different dietary lipids, 3-wk-old, weaned pigs were fed for 40 d on one of five diets, which differed only in the type of oil present (the oil contributed 5% by weight of the diet and the total fat content of the diets was 8% by weight). The oils used were soybean (control diet), high-oleic sunflower oil (HOSO), sunflower oil (SO), canola oil (CO), and fish oil (FO; rich in long-chain [n-3] polyunsaturared fatty acids). There were no significant differences in initial or final animal weights, weight gains, or health scores among the groups. There were no significant differences in the concentration of anti-Escherichia coli vaccine antibodies in the gut lumens of pigs fed the different diets. The fatty acid composition of the diet markedly affected the fatty acid composition of the plasma and of mononuclear cells (a mixture of lymphocytes, monocytes, and macrophages) prepared from the blood, lymph nodes, or thymus. The FO feeding resulted in a significant increase in the number of circulating granulocytes. The FO feeding significantly decreased the proportion of phagocytes engaged in uptake of E. coli and decreased the activity of those phagocytes that were active. The proliferation of lymphocytes in cultures of whole blood from pigs fed the HOSO, SO, or FO diets was less than in those from pigs fed the CO diet. Proliferation of lymph node lymphocytes from SO- or FO-fed pigs was less than that from control, CO-, or HOSO-fed pigs. The natural killer cell activity of blood lymphocytes from pigs fed the FO diet was significantly reduced compared with those from pigs fed the CO diet. The concentration of PGE2 in the medium of cultured blood, lymph node, or thymic mononuclear cells was lower if the cells came from pigs fed the FO diet. Thus, the type of oil included in the diet of growing pigs affects the numbers and functional activities of immune cells in different body compartments.  (+info)

(6/8527) Lipoprotein lipase expression level influences tissue clearance of chylomicron retinyl ester.

Approximately 25% of postprandial retinoid is cleared from the circulation by extrahepatic tissues. Little is known about physiologic factors important to this uptake. We hypothesized that lipoprotein lipase (LpL) contributes to extrahepatic clearance of chylomicron vitamin A. To investigate this, [3H]retinyl ester-containing rat mesenteric chylomicrons were injected intravenously into induced mutant mice and nutritionally manipulated rats. The tissue sites of uptake of 3H label by wild type mice and LpL-null mice overexpressing human LpL in muscle indicate that LpL expression does influence accumulation of chylomicron retinoid. Skeletal muscle from mice overexpressing human LpL accumulated 1.7- to 2.4-fold more 3H label than wild type. Moreover, heart tissue from mice overexpresssing human LpL, but lacking mouse LpL, accumulated less than half of the 3H-label taken up by wild type heart. Fasting and heparin injection, two factors that increase LpL activity in skeletal muscle, increased uptake of chylomicron [3H] retinoid by rat skeletal muscle. Using [3H]retinyl palmitate and its non-hydrolyzable analog retinyl [14C]hexadecyl ether incorporated into Intralipid emulsions, the importance of retinyl ester hydrolysis in this process was assessed. We observed that 3H label was taken up to a greater extent than 14C label by rat skeletal muscle, suggesting that retinoid uptake requires hydrolysis. In summary, for each of our experiments, the level of lipoprotein lipase expression in skeletal muscle, heart, and/or adipose tissue influenced the amount of [3H]retinoid taken up from chylomicrons and/or their remnants.  (+info)

(7/8527) Increased insulin sensitivity and obesity resistance in mice lacking the protein tyrosine phosphatase-1B gene.

Protein tyrosine phosphatase-1B (PTP-1B) has been implicated in the negative regulation of insulin signaling. Disruption of the mouse homolog of the gene encoding PTP-1B yielded healthy mice that, in the fed state, had blood glucose concentrations that were slightly lower and concentrations of circulating insulin that were one-half those of their PTP-1B+/+ littermates. The enhanced insulin sensitivity of the PTP-1B-/- mice was also evident in glucose and insulin tolerance tests. The PTP-1B-/- mice showed increased phosphorylation of the insulin receptor in liver and muscle tissue after insulin injection in comparison to PTP-1B+/+ mice. On a high-fat diet, the PTP-1B-/- and PTP-1B+/- mice were resistant to weight gain and remained insulin sensitive, whereas the PTP-1B+/+ mice rapidly gained weight and became insulin resistant. These results demonstrate that PTP-1B has a major role in modulating both insulin sensitivity and fuel metabolism, thereby establishing it as a potential therapeutic target in the treatment of type 2 diabetes and obesity.  (+info)

(8/8527) Lower plasma levels and accelerated clearance of high density lipoprotein (HDL) and non-HDL cholesterol in scavenger receptor class B type I transgenic mice.

Recent studies have indicated that the scavenger receptor class B type I (SR-BI) may play an important role in the uptake of high density lipoprotein (HDL) cholesteryl ester in liver and steroidogenic tissues. To investigate the in vivo effects of liver-specific SR-BI overexpression on lipid metabolism, we created several lines of SR-BI transgenic mice with an SR-BI genomic construct where the SR-BI promoter region had been replaced by the apolipoprotein (apo)A-I promoter. The effect of constitutively increased SR-BI expression on plasma HDL and non-HDL lipoproteins and apolipoproteins was characterized. There was an inverse correlation between SR-BI expression and apoA-I and HDL cholesterol levels in transgenic mice fed either mouse chow or a diet high in fat and cholesterol. An unexpected finding in the SR-BI transgenic mice was the dramatic impact of the SR-BI transgene on non-HDL cholesterol and apoB whose levels were also inversely correlated with SR-BI expression. Consistent with the decrease in plasma HDL and non-HDL cholesterol was an accelerated clearance of HDL, non-HDL, and their major associated apolipoproteins in the transgenics compared with control animals. These in vivo studies of the effect of SR-BI overexpression on plasma lipoproteins support the previously proposed hypothesis that SR-BI accelerates the metabolism of HDL and also highlight the capacity of this receptor to participate in the metabolism of non-HDL lipoproteins.  (+info)