An improved high-performance liquid chromatography method for the determination of homocysteine in human plasma

Effect of equi-molar dietary betaine and choline addition on performance, carcass quality and physiological parameters of pigs

Betaine and its precursor choline were compared in their efficiency in affecting the performance, carcass traits, and liver betaine concentration of growing-finishing pigs. Individually penned Finnish Landrace and Yorkshire pigs and their crosses (30 kg; no. = 70) were offered the basal diet with no added betaine or choline, or the basal diet supplemented with low to moderate doses (250, 500 or 1000 mg/kg) of betaine (Betafin® S1), or with a similar molar amount of choline (578, 1155 or 2310 mg/kg of choline chloride). The maize-soya-bean-meal basal diet was formulated to contain 12·3 MJ/kg digestible energy, 155 g/kg crude protein and 7·4, 4·4 and 4·3 g/kg digestible lysine, threonine and methionine + cystine, respectively. Oat hull meal (100 g/kg) was added to reduce the dietary energy concentration. The pigs were on a restricted feeding level, 1·5 to 3·0 kg food per day (proportionately 0·8 of ad libitum intake) for 75 days. Daily weight gain and food-to-gain ratio improved linearly (P < 0·01) with increasing dietary betaine. Carcass weight increased linearly (P < 0·01) but slaughter loss proportion, backfat and sidefat thicknesses and lean proportions in ham and carcass were unaffected by dietary betaine level. Liver betaine level increased linearly (by up to a proportion of 0·62 in comparison with the control) with dietary betaine addition (F < 0·05) and betaine tended to improve linearly the tensile strength of the proximal ileum (P = 0·07). The presence of choline had no effect on any of these parameters. These results indicate that low to moderate doses of dietary betaine improved the growth and the efficiency of food utilization of growing-finishing pigs. Pigs on betaine diets had heavier carcasses without a relative increase in carcass fat. Choline had no such effects in pigs offered the restricted amount of diet. Liver betaine concentration increased with level of betaine in the diet whereas the betaine precursor choline did not affect hepatic betaine.

Light and ultrastructural study in the propylthiouracil-induced hypothyroid rat heart ventricles and the ameliorating role of folic acid

Thyroid hormones have marked effects on the growth, development, and metabolic function of virtually all organs and tissues. Thyroid status is an important determinant of cardiovascular function. The present work studied the histopathological and ultrastructural changes in the hypothyroid rat left ventricle at post-pubertal stage, in addition to the ameliorating role of folic acid. A total of 50 male albino rats were randomly divided into 5 groups (group I, control; group II, folic acid; group III, propylthiouracil-induced hypothyroid rats; group IV, co-treatment with folic acid; group V, post-treatment). In order to ensure the hypothyroid state, the level of serum triiodothyronine (T(3)) and thyroid stimulating hormone (TSH) through the dose period was regularly determined. The TSH levels were significantly higher while T(3) levels were significantly lower in hypothyroid rats when compared to control group. The high-performance liquid chromatography analysis showed an increase in homocysteine (Hcy) in the hypothyroid rats group when compared to the control group. The histopathological studies of the ventricle in hypothyroid rats revealed hydrophobic changes in myofibrillar structure with striations, myocardial atrophy, nuclear pyknosis, cytoplasmic vacuoles, and cytoplasmic eosinophilia. Transmission electron micrographs in the myocardium of hypothyroid rats revealed a marked reduction in muscle fibre mass, a marked degeneration of muscle fibres, swollen mitochondria, dilated sarcoplasmic reticulum and more prominent perinuclear oedema observed in the cardiac myocytes. In co-treated hypothyroid rats with folic acid, a regular arrangement of muscle fibres, mild swelling of myofibrillar structure with striations and no continuity with adjacent myofibrils were observed while the post-treated hypothyroid rat with folic acid showed normal architecture of myofibrillar structure with striations and continuity with adjacent myofibrils. In conclusion, our results indicated that folic acid had ameliorative effect against cardiac damage induced by 6-n-propyl-2-thiouracil and the best results were found in case of using the folic acid as an adjuvant therapy after returning to the euthyroid state.

The effect of folic acid as an antioxidant on the hypothalamic monoamines in experimentally induced hypothyroid rat

Thyroid hormones are recognized as key metabolic hormones that play a critical role in the central nervous system development throughout life. In the present study, we studied the biochemical changes of hypothalamus of hypothyroid rats at post-pubertal stage, and the possible ameliorating effect of folic acid. A total of 50 male albino rats were equally divided into five groups; the first and second groups were the control and folic acid groups, respectively, while the third group was the hypothyroid group in which rats received daily 6-n-propyl-2-thiouracil (PTU) in drinking water for 6 weeks to induce hypothyroidism. The fourth and fifth groups were hypothyroid rats treated with folic acid for 4 weeks during and after receiving PTU, respectively, and were dissected after 6 and 10 weeks, respectively. There was a significant increase in plasma total homocysteine, malondialdehyde (MDA), oxidized glutathione\reduced glutathione and total nitric oxide and hypothalamic MDA, serotonin and norepinephrine in the hypothyroid rats group as compared to the control group. This reflects hyperhomocysteinaemia and oxidative stress associated with hypothyroid state. On the other hand, hypothalamic total nitric oxide and dopamine in the hypothyroid rats group were significantly decreased when compared to the control group. Treatment of hypothyroid rats with folic acid improves the oxidative stress and hypothalamic monoamines. Our results revealed that, folic acid treatment was better if it is administered as an adjuvant after returning to the euthyroid state.

Nutrition, antioxidants, and risk factor profile of nonsmokers, passive smokers and smokers of the Prevention Education Program (PEP) in Nuremberg, Germany

BACKGROUND

An elevated risk for coronary artery disease and lung cancer was reported for smokers and nonsmokers exposed to environmental tobacco smoke. Particularly in nonsmokers, in addition to the adverse effects of tobacco smoke, other factors which are associated with the exposure to environmental tobacco smoke may contribute to the health risks. We investigated both by questionnaires and biochemical analyses whether smokers influence the dietary habits of nonsmokers living in the same household.

METHODS

The study population was a subgroup of the Prevention Education Program in Nuremberg: 817 adults aged 27-66 years were allocated to one of the four groups: Nonsmokers living with a nonsmoker (Group 1), nonsmokers living with a smoker (Group 2), smokers living with a nonsmoker (Group 3), and smokers living with a smoker (Group 4).

RESULTS

The four groups did not differ in the body mass index, the concentration of lycopene, all-trans-retinol, and selenium in plasma. Plasma concentrations of high-density lipoprotein cholesterol, triglycerides, homocysteine, cobalamin, folate, beta-carotene, and alpha-tocopherol showed a gradient to unfavorable levels from Group 1 to Group 4. This trend was also reflected in the reported dietary intake of beta-carotene, alpha-tocopherol, ascorbic acid, fiber, and linoleic acid.

CONCLUSIONS

Our data show that nonsmokers living with smokers indulge in less healthy dietary habits than nonsmokers living with nonsmokers. This has to be considered when evaluating the health risks of exposure to environmental tobacco smoke.

Dietary betaine accumulates in the liver and intestinal tissue and stabilizes the intestinal epithelial structure in healthy and coccidia-infected broiler chicks

The aim of this experiment was to study the patterns of betaine accumulation into intestinal tissue, liver and plasma of broiler chicks with or without coccidial infection. The chicks were raised on a corn-based, low-betaine diet with or without 1000 ppm betaine supplementation and with or without intestinal microparasite (Eimeria maxima) challenge to the age of 21 days. Plasma, liver, intestinal tissue and digesta of non-challenged (NC) birds and plasma and intestinal tissue of coccidiosis challenged (CC) birds were analysed for betaine content. NC birds were also analyzed for homocysteine in plasma and S-adenosylmethionine (S-AM) in liver. The jejunal epithelium was histologically examined for the presence of coccidia and the crypt-villus ratio was measured. Dietary betaine supplementation decreased the plasma homocysteine concentration but had no effect on liver S-AM of NC birds. The data suggest that chicks on a low-betaine diet accumulate betaine into the intestinal tissue. When the diet was supplemented with betaine, betaine accumulated heavily into liver and to a lesser degree into intestinal tissue. The concentration of betaine in jejunal and ileal digesta was low suggesting that dietary betaine was mainly absorbed from the proximal small intestine. The coccidial challenge decreased the concentration of betaine in the liver, but greatly increased that in the intestinal tissue. The crypt-villus ratio was decreased by the dietary betaine supplementation in healthy and challenged chicks, suggesting that dietary betaine both protects the jejunal villi against coccidial infection and also stabilizes the mucosal structure in healthy broiler chicks. These results support our earlier findings suggesting that betaine is likely to act as an important intestinal osmolyte in broiler chicks.