Inadequate vitamin D status is associated with lower food plus supplemental intake of vitamin D in children of South Asian ethnicity living in the National Capital Region of Canada.

Vitamin D status, measured in a Vitamin D Standardization Program certified laboratory, was assessed among children of South Asian and European ethnicity living in the national capital region of Canada to explore factors that may account for inadequate status. Demographic information, dietary and supplemental vitamin D over 30 d prior to measurement of serum 25-hydroxyvitamin D (25OHD), and anthropometry were measured (age 6.0-18.9 y; n = 58/group; February-March 2015). No group related differences in age, height and body mass index (BMI) Z-scores or in food vitamin D intakes were observed. Standardized serum 25OHD was lower in South Asian children (mean ± SD: 39.0 ± 16.8 nmol/L vs. European: 58.4 ± 15.8 nmol/L). A greater proportion of South Asian children had serum 25OHD <40 nmol/L (56.9 vs. 8.6%, P < 0.0001) and fewer took supplements (31 vs. 50%, P = 0.0389). In a multi-factorial model (r2 = 0.54), lower vitamin D status was associated with overweight/obese BMI and older age (14-18 y); no interaction with ethnicity was observed. Lower vitamin D status was associated with lower total vitamin D intake only in South Asian children. This study reinforces the importance of public health actions towards meeting vitamin D intake recommendations among those of high-risk deficiency. Novelty: A higher proportion of South Asian vs. European children had inadequate vitamin D status. Lower vitamin D status was associated with a BMI in the overweight/obese range. Lower vitamin D status was associated with lower total vitamin D intake in South Asian but not European children.

Acute anti-inflammatory and anti-nociceptive activities of crude extracts, alkaloid fraction and evolitrine from Acronychia pedunculata leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Acronychia pedunculata (family: Rutaceae) is one of the commonly used medicinal plants in Sri Lankan traditional medicine. Different parts of this plant are used for the treatment of inflammatory conditions in the form of medicinal oils and herbal porridge. AIM OF THE STUDY: The present study aimed to evaluate the anti-nociceptive activity and anti-inflammatory activity with their mechanisms and the acute toxicity of crude extracts of the fresh leaves of A. pedunculata for scientific validation of the ethnopharmacological claims for this plant. Further, attention has been focused on the isolation of active compounds from active fractions of the crude extracts. MATERIALS AND METHODS: The acute anti-inflammatory effect of the aqueous (AELA) and 70% ethanol crude extracts (EELA) and alkaloid fraction of A. pedunculata leaves were evaluated by the determination of inhibition of hind paw oedema induced by carrageenan in Wistar rats. Evolitrine was identified as the major alkaloid with significant bioactivities by column chromatography and NMR. The anti-nociceptive and anti-histamine activities of EELA and evolitrine were evaluated by acetic acid induced writhing and wheal formation tests respectively. In addition, in-vitro (2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay) and in-vivo (lipid peroxidation assay) anti-oxidant activity, nitric oxide (NO) inhibitory activity and acute toxicity of EELA were evaluated. RESULTS: Acute anti-inflammatory activity of AELA and EELA were dose-dependent. EELA was more active than AELA. The 200 mg/kg body weight (b. w.) dose of EELA was found as the minimum effective dose with maximum inhibition (78%) of oedema at 5th hour compared to the negative control (p < 0.05). Evolitrine was isolated and identified as an active anti-inflammatory and analgesic compound from active alkaloid fraction of EELA. Evolitrine showed activity enhancement when compared with crude EELA. The anti-inflammatory and analgesic activities of evolitrine (50 mg/kg b. w.) were comparable to that of reference drugs indomethacin (5 mg/kg b. w) and acetylsalicylic acid (100 mg/kg b. w.). The significant (p < 0.05) anti-histamine activity, DPPH scavenging in-vitro anti-oxidant activity, in-vivo lipid peroxidation inhibitory activity in-vivo, NO inhibitory activity of EELA as compared with relevant negative controls, were identified as probable mechanisms which mediated its anti-inflammatory action. Further, EELA showed a high safety margin in the limited dose acute toxicity study. CONCLUSION: The findings of the current study rationalize the usage of leaves of A. pedunculata in Sri Lankan traditional medicine as an analgesic and anti-inflammatory agent. Possible mechanisms mediating this activity included anti-histamine, anti-oxidant and NO inhibitory activities. Evolitrine is the major analgesic and anti-inflammatory compound isolated from the active alkaloid fraction of EELA.

Low 25-hydroxyvitamin D levels are more prevalent in Canadians of South Asian than European ancestry inhabiting the National Capital Region of Canada.

The US Institute of Medicine defined serum 25-hydroxyvitamin D (25OHD) cut point values of 30 nmol/L and 40 nmol/L were used to assess the vitamin D status of South Asian and European Canadians of self-identified ancestry living in the National Capital Region of Canada. Serum 25OHD values were measured in the spring and fall of 2012 to represent status during the winter and summer months, respectively. A total of 1238 measurements were obtained from 669 participants (49% South Asian ancestry): some participants were measured only once (spring or fall). Median 25OHD values were significantly higher in participants of European ancestry: 70.8 nmol/L (68.1, 73.5; 95% CI) versus South Asian ancestry: 42.7 nmol/L (40.5, 45.0; P<0.001). Spring vs. fall differences were small for each ethnic group and significant only for those of European ancestry (2.9, CI: 1.0-4.9 nmol/L; P = 0.01). Among participants of South Asian ancestry, 27.3% (fall) and 29.1% (spring) of females had values <40 nmol/L while the percentages for males were considerably higher (36.5% and 44.2%, respectively). The corresponding values for participants of European ancestry were ≤10%, showing that the South Asian participants were less likely to achieve the 25OHD concentrations established by the IOM for optimum bone health. Investigation of the factors related to serum 25OHD levels showed that supplement intake and ethnic background were associated with the biggest differences. Skin color was not a major factor, suggesting that genetic factors are responsible for the observed differences between participants of different ethnic backgrounds.

Lower serum magnesium concentration is associated with diabetes, insulin resistance, and obesity in South Asian and white Canadian women but not men.

BACKGROUND: A large proportion of adults in North America are not meeting recommended intakes for magnesium (Mg). Women and people of South Asian race may be at higher risk for Mg deficiency because of lower Mg intakes relative to requirements and increased susceptibility to diabetes, respectively. OBJECTIVE: This study compared serum Mg concentrations in South Asian (n=276) and white (n=315) Canadian women and men aged 20-79 years living in Canada's Capital Region and examined the relationship with diabetes, glucose control, insulin resistance, and body mass index. RESULTS: Serum Mg concentration was lower in women of both races and South Asians of both genders. Racial differences in serum Mg were not significant after controlling for use of diabetes medication. A substantial proportion of South Asian (18%) and white (9%) women had serum Mg <0.75 mmol/L indicating hypomagnesemia. Use of diabetes medication and indicators of poorer glucose control, insulin resistance, and obesity were associated with lower serum Mg in women, but not in men. CONCLUSIONS: These results suggest that the higher incidence of diabetes in South Asians increases their risk for Mg deficiency and that health conditions that increase Mg requirements have a greater effect on Mg status in women than men.

Effects of Jatropha oil on rats following 28-day oral treatment.

Jatropha oil is an emerging feedstock for the production of biodiesels. The increasing use of this nonedible, toxic oil will result in higher potential for accidental exposures. A repeated-dose 28-day oral toxicity study was conducted to provide data for risk assessment. Jatropha oil diluted in corn oil was administered by gavage to male and female rats at 0.5, 5, 50 and 500 mg kg(-1) body weight per day for 28 consecutive days. Control rats were administered corn oil only. The growth rates and consumption of food and water were monitored. At necropsy, organs were weighed and hematological parameters assessed. Serum clinical chemistry and C-reactive protein were measured and histological examinations of organs and tissues were performed. Markedly depressed growth rate was observed in males and females receiving Jatropha oil at 500 mg kg(-1) per day. Decreased white blood cell and lymphocyte counts were detected in females at 50 and 500 mg kg(-1) per day and in males at 500 mg kg(-1) per day. These changes were correlated to mild and reversible histological changes in male and female spleens. In the liver, a mild increase in portal hepatocytes cytoplasm density was observed in males and females, while periportal vacuolation was observed exclusively in females. Mild acinar proliferation was observed in the female mammary glands at all dose levels. It is concluded that Jatropha oil produces adverse effects on female rats starting at 50 mg kg(-1) per day with decreased white blood cell and lymphocyte counts and at 500 mg kg(-1) per day in both genders in term of depressed growth rates.

High-dose supplemental selenite to male Syrian hamsters fed hypercholesterolaemic diets alters Ldlr, Abcg8 and Npc1l1 mRNA expression and lowers plasma cholesterol concentrations.

The aim of the present study was to elucidate possible cholesterol-lowering mechanism(s) of high-dose supplemental Se in the form of selenite, a known hypocholesterolaemic agent. Male Syrian hamsters (four groups, ten per group) were fed semi-purified diets for 4 weeks containing 0.1 % cholesterol and 15 % saturated fat with selenite corresponding to varying levels of Se: (1) Se 0.15 parts per million (ppm), control diet; (2) Se 0.85 ppm; (3) Se 1.7 ppm; (4) Se 3.4 ppm. Lipids were measured in the bile, faeces, liver and plasma. The mRNA expression of several known regulators of cholesterol homeostasis (ATP-binding cassette transporters g5 (Abcg5) and g8 (Abcg8), 7-hydroxylase, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, LDL receptor (LdLr) and Nieman-Pick C1-like 1 protein (Npc1l1)) were measured in the liver and/or jejunum. Oxysterols including 24-(S)-hydroxycholesterol, 25-hydroxycholesterol and 27-hydroxycholesterol (27-OHC) were measured in the liver. Significantly lower total plasma cholesterol concentrations were observed in hamsters consuming the low (0.85 ppm) and high (3.4 ppm) Se doses. The two highest doses of Se resulted in decreased plasma LDL-cholesterol concentrations and increased mRNA levels of hepatic Abcg8, Ldlr and jejunal Ldlr. Higher hepatic 27-OHC and TAG concentrations and lower levels of jejunal Npc1l1 mRNA expression were noted in the 1.7 and 3.4 ppm Se-treated hamsters. Overall, Se-induced tissue changes in mRNA expression including increased hepatic Abcg8 and Ldlr, increased jejunal Ldlr and decreased jejunal Npc1l1, provide further elucidation regarding the hypocholesterolaemic mechanisms of action of Se in the form of selenite.

Trans and saturated fat on food labels in Canada: fact or fiction?

OBJECTIVE: Food labels are the number one source for nutrition information for Canadians, but are food labels accurate? This study aims to provide an assessment of the accuracy of the reported trans fatty acid and saturated fatty acid values on food labels in selected foods. METHODS: Over 380 samples of cookies, crackers, granola bars, breakfast bars and a variety of frozen foods were collected between 2005 and 2008 in the Greater Toronto Area, Ottawa and Vancouver, as part of Health Canada's Trans Fat Monitoring Program. The food categories chosen were based on earlier studies indicating that they were significant sources of trans fatty acids and the individual samples were chosen based on market share data. The trans fatty acid and saturated fatty acid contents of the samples were determined by gas chromatography and the laboratory results were compared to the values reported in the Nutrition Facts tables. CONCLUSIONS: Statistical analysis indicated no significant difference between laboratory and food label values for cookies, crackers, granola bars, breakfast bars and frozen foods for trans fat or saturated fat. The results demonstrate that Canadians can rely on food labels for making informed dietary choices with respect to trans fat and saturated fat content.

Increasing Dietary alpha-linolenic acid enhances tissue levels of long-chain n-3 PUFA when linoleic acid intake is low in hamsters.

BACKGROUND/AIMS: We tested whether feeding hamsters diets varying in alpha-linolenic acid (ALA) content and low in linoleic acid (LA) could increase the tissue levels of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) to the same extent as a fish oil-supplemented diet. METHODS: For 5 weeks, 60 hamsters were fed 1 of the following 5 diets containing 2% of total dietary energy (TE) as LA and either 0.5% (diet A), 1% (diets B and E), 2% (diet C), or 4% (diet D) ALA of TE, so that the ratio of LA/ALA was 4:1, 2:1, 1:1, or 1:2. Diet E was supplemented with fish oil at the level of 0.2% of total energy intake. At the end of the study, overnight-fasted hamsters were sacrificed, and blood and tissues were collected. RESULTS: Tissue levels of ALA, EPA, DPA, and DHA rose in proportion to the increase in the dietary ALA level (p < 0.01); however, the levels of DHA reached a plateau at ALA intakes above 1% (p < 0.01). These changes were accompanied by decreases in arachidonic acid with or without increases in LA levels (p < 0.01). Hamsters fed diet D had similar or higher EPA, DPA, and DHA tissue levels to those fed diet E (p < 0.01). CONCLUSIONS: In hamsters, diets containing 4% energy as ALA and 2% energy as LA can increase the tissue levels of EPA, DPA, and DHA to the same extent as feeding 0.2% energy as fish oil.

Antioxidant Supplements Improve Profiles of Hepatic Oxysterols and Plasma Lipids in Butter-fed Hamsters.

Hypercholesterolemic diets are associated with oxidative stress that may contribute to hypercholesterolemia by adversely affecting enzymatically-generated oxysterols involved in cholesterol homeostasis. An experiment was conducted to examine whether the cholesterol-lowering effects of the antioxidants selenium and α-tocopherol were related to hepatic oxysterol concentrations. Four groups of male Syrian hamsters (n = 7-8) were fed high cholesterol and saturated fat (0.46% cholesterol, 14.3% fat) hypercholesterolemic semi-purified diets: 1) Control; 2) Control + α-tocopherol (67 IU all-racemic-α-tocopheryl-acetate/kg diet); 3) Control + selenium (3.4 mg selenate/kg diet); and 4) Control + α-tocopherol + selenium. Antioxidant supplementation was associated with lowered plasma cholesterol concentrations, decreased tissue lipid peroxidation and higher hepatic oxysterol concentrations. A second experiment examined the effect of graded selenium doses (0.15, 0.85, 1.7 and 3.4 mg selenate/kg diet) on mRNA expression of the oxysterol-generating enzyme, hepatic 27-hydroxylase (CYP27A1, EC 1.14.13.15), in hamsters (n = 8-9) fed the hypercholesterolemic diets. Supplementation of selenium at 3.4 mg selenate/kg diet was not associated with increased hepatic 27-hydroxylase mRNA. In conclusion, the cholesterol lowering effects of selenium and α-tocopherol were associated with increased hepatic enzymatically generated oxysterol concentrations, which appears to be mediated via improved antioxidant status rather than increased enzymatic production.

Trans fatty acids: current contents in Canadian foods and estimated intake levels for the Canadian population.

Research conducted in the mid-1990s indicated that the levels of trans fats in Canadian diets were among the highest in the world. The consumption of trans fats raises blood levels of low-density lipoprotein (LDL)-cholesterol, while reducing levels of high-density lipoprotein (HDL)-cholesterol. In June 2007, Health Canada called on the food industry to voluntarily reduce levels of trans fats in vegetable oils and soft (tub)-margarines to < 2% of total fat, and in all other foods, to < 5%. Industry must show satisfactory progress by June 2009, or Health Canada might have to introduce legislation to ensure that recommended limits are achieved. Since 2005, Health Canada has been performing a national assessment of prepackaged and restaurant foods that likely contain trans fats. From 2005 to 2009, 1120 samples were analyzed, of which 852 or approximately 76% met the recommended trans fat limits. As a result of reformulation, most of the products had decreased trans + saturated fat content. The estimated average intake of trans fatty acids (TFA) in Canada significantly dropped from the high value of 8.4 g/day in the mid-1990s to 3.4 g/day (or 1.4% food energy) in 2008. However, this TFA intake of 1.4% of energy is still above the World Health Organization recommended limit of TFA intake of < 1% of energy, which suggests that the Canadian food industry needs to put more effort into reducing the TFA content in its products, especially in tub-margarines, donuts, and bakery products.

Increased incorporation of dietary plant sterols and cholesterol correlates with decreased expression of hepatic and intestinal Abcg5 and Abcg8 in diabetic BB rats.

The aim of this study was to determine the impact of dietary plant sterols and stanols on sterol incorporation and sterol-regulatory gene expression in insulin-treated diabetic rats and nondiabetic control rats. Diabetic BioBreeding (BB) and control BB rats were fed a control diet or a diet supplemented with plant sterols or plant stanols (5 g/kg diet) for 4 weeks. Expression of sterol-regulatory genes in the liver and intestine was assessed by real-time quantitative polymerase chain reaction. Diabetic rats demonstrated increased tissue accumulation of cholesterol and plant sterols and stanols compared to control rats. This increase in cholesterol and plant sterols and stanols was associated with a marked decrease in hepatic and intestinal Abcg5 (ATP-binding cassette transporter G5) and Abcg8 (ATP-binding cassette transporter G8) expressions in diabetic rats, as well as decreased mRNA levels of several other genes involved in sterol regulation. Plant sterol or plant stanol supplementation induced the accumulation of plant sterols and stanols in tissues in both rat strains, but induced a greater accumulation of plant sterols and stanols in diabetic rats than in control rats. Surprisingly, only dietary plant sterols decreased cholesterol levels in diabetic rats, whereas dietary plant stanols caused an increase in cholesterol levels in both diabetic and control rats. Therefore, lower expression levels of Abcg5/Abcg8 in diabetic rats may account for the increased accumulation of plant sterols and cholesterol in these rats.

Nationwide product reformulations to reduce trans fatty acids in Canada: when trans fat goes out, what goes in?

The impact of recent efforts to reduce the content of industrially produced trans fatty acids (TFA) in foods has not been systematically assessed in any country. Concerns exist that food manufacturers/restaurants may replace TFA with saturated fat acids (SFA), rather than cis unsaturated fats, or increase the total fat content. We present findings from a national systematic assessment of grocery and restaurant foods likely to contain TFA in Canada in 2005-2007. Of the total of 221 assessed products, 92 (42%) contained TFA (> or = 5% of fatty acids) on initial assessment. Of an unselected sample assessed more than once, 72% were reformulated during 2005-2007: mean+/-s.d. TFA levels decreased from 26+/-13 to 2+/-4%. Following reformulation, one product had similar TFA+SFA content; all others had decreased TFA+SFA and increased cis unsaturated fat content. The total fat content was generally unaffected. The findings suggest that manufacturers/restaurants generally take advantage of costs and efforts of reformulation to not only reduce TFA but also increase the content of cis unsaturated fats.

Impact of dietary protein on lipid metabolism in hamsters is source-dependent and associated with changes in hepatic gene expression.

This study tested the hypothesis that protein source is a factor determining the impact of the diet on lipid metabolism in hamsters. Twenty-eight hamsters of similar body weight were assigned for a period of 8 weeks to one of the following four diets (seven per group) containing either 20 % (w/w) casein (CAS), beef protein (BF), wheat gluten (WG) or soya protein (SOY). The fat composition of the diet was the same (15.5 % w/w) in all groups and provided SFA, MUFA and PUFA representative of the average Canadian diet. After an overnight fast, blood and liver were collected for the measurement of serum lipids, fatty acid composition of liver phospholipids and mRNA levels of selected genes involved in lipid metabolism. WG resulted in lower total cholesterol, HDL-cholesterol and non-HDL-cholesterol but, along with SOY, in higher mRNA levels of cholesterol 7 alpha-hydroxylase and LDL receptor. Furthermore, both WG and SOY resulted in lower 18 : 3n-3, 20 : 4n-6, total n-6 PUFA, 18 : 1n-9 and total MUFA, but higher 22 : 6n-3, total n-3 PUFA, 22 : 6n-3/18 : 3n-3 and 22 : 5n-3/18 : 3n-3 ratios in liver phospholipids, and higher hepatic Delta6-desaturase mRNA levels. These results show that the impact of dietary protein on lipid metabolism is source-dependent and associated with changes in mRNA abundances of key hepatic enzymes and receptors.

Effects of supplemental cystine or methionine on growth and lifespan of stroke-prone spontaneously hypertensive rats.

Stroke-prone spontaneously hypertensive (SHRSP) rats are considered a suitable model for studying the effects of dietary and other environmental factors on human essential hypertension and haemorrhagic stroke. To investigate the suitability of a control diet for this strain of rats, we studied the effects of supplementing casein and soya protein isolate (SPI) with two sulphur amino acids (methionine and cystine) on the growth and lifespan of SHRSP rats. The source of dietary protein and the type of supplemental sulphur amino acid had significant (P < 0.05) effects on food intake and weight gain measured after 31 d of the feeding study, while only the type of supplemental sulphur amino acid had significant effects on mean survival times and the survival rates. On average, the casein groups had higher food intake and weight gain compared with the SPI groups. The methionine-supplemented groups had lower food intake but higher weight gain than the cystine-supplemented groups. Similarly, the methionine-supplemented groups had higher mean survival times and survival rates compared with the cystine-supplemented groups. The data would suggest that a control diet based on cystine-supplemented casein (as recommended for normal healthy rats by the American Institute of Nutrition), may not meet the sulphur amino acid requirements for SHRSP rats, and that the methionine-supplemented casein would be an appropriate control diet for this animal model.

Limited effects of combined dietary copper deficiency/iron overload on oxidative stress parameters in rat liver and plasma.

Copper (Cu) deficiency decreases the activity of Cu-dependent antioxidant enzymes such as Cu,zinc-superoxide dismutase (Cu,Zn-SOD) and may be associated with increased susceptibility to oxidative stress. Iron (Fe) overload represents a dietary oxidative stress relevant to overuse of Fe-containing supplements and to hereditary hemochromatosis. In a study to investigate oxidative stress interactions of dietary Cu deficiency with Fe overload, weanling male Long-Evans rats were fed one of four sucrose-based modified AIN-93G diets formulated to differ in Cu (adequate 6 mg/kg diet vs. deficient 0.5 mg/kg) and Fe (adequate 35 mg/kg vs. overloaded 1500 mg/kg) in a 2 x 2 factorial design for 4 weeks prior to necropsy. Care was taken to minimize oxidation of the diets prior to feeding to the rats. Liver and plasma Cu content and liver Cu,Zn-SOD activity declined with Cu deficiency and liver Fe increased with Fe overload, confirming the experimental dietary model. Liver thiobarbituric acid reactive substances were significantly elevated with Fe overload (pooled across Cu treatments, 0.80+/-0.14 vs. 0.54+/-0.08 nmol/mg protein; P<.0001) and not affected by Cu deficiency. Liver cytosolic protein carbonyl content and the concentrations of several oxidized cholesterol species in liver tissue did not change with these dietary treatments. Plasma protein carbonyl content decreased in Cu-deficient rats and was not influenced by dietary Fe overload. The various substrates (lipid, protein and cholesterol) appeared to differ in their susceptibility to the in vivo oxidative stress induced by dietary Fe overload, but these differences were not exacerbated by Cu deficiency.

Alpha-linolenic acid but not conjugated linolenic acid is hypocholesterolaemic in hamsters.

Conjugated linolenic acid (CLN) refers to a group of octadecatrienoic acid isomers that have three double bonds in conjugation. Both pomegranate and tung seed oils are rich in CLN but the major isomer in the former is cis9,trans11,cis13 while in the latter it is cis9,trans11,trans13. The present study examined the effects of CLN, isolated from either pomegranate seed oil or tung seed oil, and alpha-linolenic acid (LN), isolated from flaxseed oil, on serum cholesterol levels in male hamsters (body weight 105 g; age 10 weeks) fed a 0.1% cholesterol and 10% lard diet, for a period of 6 weeks. All hamsters were allowed free access to food and fluid. The blood samples were taken by bleeding from the retro-orbital sinus into a heparinized capillary tube under light ether anaesthesia after overnight fasting at weeks 0, 2, 4 and 6. It was found that supplementation of CLN at levels of 12.2-12.7 g/kg diet exhibited no significant effect on serum cholesterol level while LN at a similar level of supplementation had serum cholesterol reduced by 17-21% compared with the control diet containing no LN and CLN. Supplementation of CLN and LN significantly decreased hepatic cholesterol but no effect was observed on heart and kidney cholesterol levels. It was concluded that LN possessed hypocholesterolaemic activity while CLN had no effect on blood cholesterol, at least in hamsters.