Somsri Charoenkiatkul

Protective Effects of Coenzyme Q10 on Decreased Oxidative Stress Resistance Induced by Simvastatin

The effects of simvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase), on oxidative stress resistance and the protective effects of coenzyme Q (CoQ) were investigated. When simvastatin was administered orally to mice, the levels of oxidized and reduced CoQ9 and CoQ10 in serum, liver, and heart, decreased significantly when compared to those of control. The levels of thiobarbituric acid reactive substances induced by Fe2+-ascorbate in liver and heart mitochondria also increased significantly with simvastatin. Furthermore, cultured cardiac myocytes treated with simvastatin exhibited less resistance to oxidative stress, decreased time to the cessation of spontaneous beating in response to H2O2 addition, and decreased responsiveness to electrical field stimulation. These results suggested that oral administration of simvastatin suppresses the biosynthesis of CoQ, which shares the same biosynthesis pathway as cholesterol up to farnesyl pyrophosphate, thus compromising the physiological function of reduced CoQ, which possesses antioxidant activity. However, these undesirable effects induced by simvastatin were alleviated by coadministering CoQ10 with simvastatin to mice. Simvastatin also reduced the activity of NADPH-CoQ reductase, a biological enzyme that converts oxidized CoQ to the corresponding reduced CoQ, while CoQ10 administration improved it. These findings may also support the efficacy of coadministering CoQ10 with statins.

Effect of urbanization on bone mineral density: A Thai epidemiological study

BackgroundThe incidence of fractures in rural populations is lower than in urban populations, although the reason for this difference is unclear. This cross-sectional study was designed to examine the difference in bone mineral density (BMD), a primary predictor of fracture risk, between urban and rural Thai populations.MethodsFemoral neck and lumbar spine BMD was measured by dual-energy X-ray absorptiometry (GE Lunar, Madison, WI) in 411 urban and 436 rural subjects (340 men and 507 women), aged between 20 and 84 years. Body mass index (BMI) was calculated from weight and height.ResultsAfter adjusting for age and body weight in an analysis of covariance model, femoral neck BMD in rural men and women was significantly higher than those in urban men and women (P < 0.001), but the difference was not observed at the lumbar spine. After stratifying by sex, age group, and BMI category, the urban-rural difference in femoral neck BMD became more pronounced in men and women aged <50 years and with BMI ≥ 25 kg/m2.ConclusionsThese data suggest that femoral neck BMD in rural men and women was higher than their counterparts in urban areas. This difference could potentially explain part of the urban-rural difference in fracture incidence.

Inhibitory effects of spices and herbs on iron availability

Spices and herbs are extensively used in indigenous diets in tropical regions where prevalence of iron deficiency is still high. They are rich in polyphenolic compounds that are expected to inhibit iron absorption by forming iron complexes in the intestine, making dietary iron less available for absorption. The effects of six spices and herbs (chili pepper, garlic, ‘Pak kyheng’ (Thai leafy vegetable), shallot, tamarind, turmeric) and one mixture of spices (curry paste) on iron availability were determined by measuring the percentage dialyzable iron after addition of spices and herbs to a rice meal after simulated digestion. All tested spices and herbs contained from 0.5 to 33 mg polyphenol per meal and were potent inhibitors of iron availability (20–90%), reducing iron availability in a dose-dependent manner—with the exception of tamarind, which at 11 mg polyphenol per meal enhanced iron availability. Our findings demonstrate that culinary spices and herbs can play an important role in iron nutrition.

Nutrients and bioactive compounds of Thai indigenous fruits.

This study determined the nutritional potential of Thai indigenous fruits in terms of nutrients, bioactive compounds, and antioxidant activities. Three indigenous fruits were collected at two conservation areas in Kanchanaburi province, Thailand. The results showed that Phyllanthus emblica L. exhibited the highest levels of vitamin C (575±452mg/100g), total phenolics (TP) (3703±1244mGAE/100g), and antioxidant activities, as measured by DPPH, FRAP and ORAC assays. Compared to the other two fruits, Antidesma velutinosum Blume contained higher levels of most nutrients and dietary fibre (15.6±5.9g/100g), as well as carotenoids (335±98μg/100g) and phytosterols (22.1±3.9mg/100g). Spondias pinnata (L.f.) Kurz was high in total phenolics (3178±887mGAE/100g) and antioxidant activity. Moreover, high correlations were found between TP and antioxidant activities (r>0.9). These Thai indigenous fruits are potentially good sources of nutrients, bioactive compounds, and antioxidant activities. Conservation and utilisation should be promoted for food security and consumption as part of a healthy diet.

Calcium Absorption from Commonly Consumed Vegetables in Healthy Thai Women

The absorbability of calcium from ivy gourd, a green leafy vegetable (Coccinia grandix Voigt.) and winged bean young pods (Psophocarpus tetragonolobus [L] DC) were measured in 19 healthy adult women aged 20 to 45 y, in a 3-way, randomized-order, crossover design with an average calcium load of 100 mg and milk as the referent. The test meals were extrinsically labeled with 44Ca and given with rice as breakfast after an overnight fast. Absorption of calcium was determined on a blood sample drawn 5 h after ingestion of the test meal. Fractional calcium absorption (X+/- SD) was 0.391 +/- 0.128 from winged beans, 0.476 +/- 0.109 from ivy gourd, and 0.552 +/- 0.119 from milk. The difference in fractional calcium absorption for these 2 vegetables was significant (P < 0.05) and the fractional calcium absorption from these 2 vegetables were both significantly lower than from milk. The difference was partly accounted for by the phytate, oxalate, and dietary fiber content of the vegetables. However, calcium bioavailability of these 2 vegetables, commonly consumed among Thais, was relatively good compared to milk (71% to 86% of milk) and could be generally recommended to the public as calcium sources other than milk and Brassica vegetables.

Anti-inflammatory activities of red curry paste extract on lipopolysaccharide-activated murine macrophage cell line

OBJECTIVE This study investigated anti-inflammatory and antioxidant activities of an ethanol extract from Thai red curry paste. METHODS The RAW264.7 murine macrophage cell line was incubated with the extract (65-260 μg/mL) with or without lipopolysaccharide. The anti-inflammatory activities of the extract were examined by measuring inducible nitric oxide synthase, cyclo-oxygenase-2, tumor necrosis factor-α, and interleukin-6 mRNA and protein level by reverse transcription-polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay, respectively. Nitric oxide production and intracellular reactive oxygen species generation were determined by the Griess method and fluorescence intensity. The activation of mitogen-activated protein kinases and inhibitor κB were determined by western blot. RESULTS Exposure of cells with the extract significantly suppressed lipopolysaccharide-induced nitric oxide production and inducible nitric oxide synthase, cyclo-oxygenase-2, tumor necrosis factor-α, and interleukin-6 expressions (P < 0.05) by dose-dependently without cytotoxic effect. Intracellular reactive oxygen species significantly decreased (P < 0.05) in lipopolysaccharide-induced RAW264.7 cells. The inhibitory effect was mediated partly by inhibiting activation of inhibitor κB-α and mitogen-activated protein kinases. CONCLUSION These results suggest that the anti-inflammatory and antioxidant properties of Thai red curry paste stem from bioactive compounds present in the spice and herb constituents. The health benefits of Thai red curry paste warrant further investigations in vivo.

Biochemical markers of bone formation in Thai children and adolescents.

The measurement of biochemical markers of bone turnover is essential in the study of skeletal metabolism in health and diseases. Due to variations in the rate of bone growth in different age groups and possible ethnic differences, age-specific reference ranges for biochemical markers should be established in a particular pediatric population. In this study, biochemical markers of bone formation, bone-specific alkaline phosphatase (BAP), and osteocalcin (OC) in healthy Thai children and adolescents aged 9 to 18 years were evaluated in relation to their ages and pubertal development. Serum BAP levels in boys increased with age and peaked at about 12 to 13 years. In contrast, there was a progressive decline of serum BAP levels with advancing age in girls older than 9 years. Serum OC also increased with age and reached a peak at ages 12 and 13 years in girls and boys, respectively. In addition, both serum BAP and OC levels also varied with pubertal stages. The BAP levels in boys increased sharply at pubertal stage 3 and decreased at pubertal stage 5. In girls, the BAP levels showed a fairly constant high level up to stage 3, followed by a remarkable decrease thereafter. The OC levels in boys increased sharply at pubertal stage 4 and decreased thereafter. In girls, OC started to increase at pubertal stage 3 with no subsequent changes. The levels of serum BAP and OC were higher in boys than in girls at pubertal stages 3 to 5 and at stages 2, 4, and 5, respectively. Moreover, only serum BAP level showed significant positive correlation with height velocity in both genders. In multiple regression analyses, gender, age, and pubertal stage were consistently correlated with both serum BAP and OC levels. In summary, male and female adolescents have different patterns of changes in biochemical markers of bone formation.

Nutrients and bioactive compounds in popular and indigenous durian (Durio zibethinus murr.).

This study identified nutrients, fatty acids, bioactive compounds and antioxidant activities of two popular varieties (Mon-thong, Cha-ni) and two indigenous varieties (Kra-dum and Kob-ta-kam) of durian. Each of variety was collected from 3 gardens in Nonthaburi province, Thailand. At optimal ripeness, the edible part was separated, homogenised or freeze dried, as fresh or dry samples for further analysis using standard methods. All durian varieties contained a considerable amount of dietary fibre (7.5-9.1g/100g dry matter, DM) and high amounts of carbohydrate and sugar (62.9-70.7g and 47.9-56.4g/100g DM respectively). Cha-ni, Kra-dum and Kob-ta-kam varieties had monounsaturated (MUFA) (6.1-7.8g/100g DM)>saturated (SFA) (4.2-5.7g/100g DM)>polyunsaturated fatty acid (PUFA) (0.8-1.5g/100g DM), whereas the Mon-thong variety had SFA>MUFA>PUFA (5.1, 4.0, 1.1g/100g DM, respectively). The Kob-ta-kam variety showed greater potential for health benefits in terms of carotenoids and β-carotene (2248μg and 1202μg/100g DM respectively). Phenolic compounds and antioxidant capacity were not significantly different among each variety, though the Cha-ni variety had the lowest. This study provides data on nutrients, bioactive compounds and antioxidant activities of indigenous and popular durian varieties that could be used for consumer education as well as for incorporation into the food composition databases.

Conventional steaming retains tocols and γ-oryzanol better than boiling and frying in the jasmine rice variety Khao dok mali 105.

The aim of this study was to determine the effect of various cooking methods on the white rice (WR), brown rice (BR) and parboiled geminated brown rice (PGBR) of the same variety, focusing on γ-oryzanol and tocols. The methods used for analysis of γ-oryzanol and tocols included solvent extraction and HPLC. The results indicated that PGBR had a higher content of γ-oryzanol and tocols compared to BR and WR, when different cooking methods (raw, steamed, boiled and fried) were used. Steaming method retained the higher γ-oryzanol content (53.6-62.2mg/100g) in both PGBR and BR, in comparison with boiling (53.0-60.6mg/100g) and frying (23.4-31.5mg/100g) methods. Frying reduced the γ-oryzanol content significantly regardless of the rice type. Regarding tocols, a similar trend was noticed in all the methods studied. Tocotrienol was the most abundant tocol found in PGBR and BR. Therefore, steaming is the best cooking method to preserved most of the bioactive compounds; however, a slight increase in total tocols was observed after frying.

Sexual maturation in Thai boys.

BACKGROUND A worldwide secular trend towards earlier onset of puberty in girls has been noted during recent years. However, the data on sexual maturation of boys are relatively scarce and normative data of sexual maturation in Thai boys are still lacking. AIM To determine the age of secondary sexual maturation in normal Thai boys. METHODS Three hundred healthy urban boys aged 9-18 years were recruited during January 1997 to December 1999. Genital and pubic hair maturity staging was determined using the method of Marshall and Tanner. Testicular size was assessed by Prader orchidometer. Probit analysis was used to analyze the onset of puberty (gonadarche) and pubarche. RESULTS Median (range) ages of the onset of puberty and pubarche were 10.8 (9.5-12) and 12.4 (10.9-13.9) years, respectively. CONCLUSION The age of onset of genital development in boys living in Bangkok seems to be slightly earlier than that of boys in other countries. However, the onset of pubic hair development is comparable.