The toxic effects of pentachlorophenol (PCP) on haematological parameters in olive flounder (Paralichthys olivaceus) after chronic exposure to dietary PCP (0.1, 0.5 and 1.0 mg/kg diet) for 2, 4 and 6 weeks were studied. A significant decrease in total RBC count, haemoglobin concentration and hematocrit value was noted in fish exposed to PCP compared to the non-exposed fish. The PCP treatment group showed significantly lower concentration of serum total protein and albumin, and significantly higher serum chloride, magnesium and total bilirubin levels compared with those in the control group. However, PCP had no major effects on serum glucose, total cholesterol, phosphate and calcium ions in flounder. These results demonstrated that PCP have induced adverse haematological impacts in the olive flounder, Paralichthys olivaceus. Because we found damages in blood-forming function and disruption in blood homeostasis due to chronic exposure to PCP, it is needed to develop further experimental studies for the risk assessment of this environmental pollutant.
Stress is a global menace exacerbated by the advancement of industrialization. Failure of stress management is to a breakdown of the psychological and physiological protection mechanisms against stress. The aim of present study was to investigate the anti-stress potential of ginseng against immobilization stress. Male Sprague-Dawley rats (n=24) were divided into three groups; (i) control, (ii) immobilization stress (2hr daily, for 2 weeks), and (iii) immobilization stress (2 hr daily, for 2 weeks) plus oral administration of ginseng (200 mg/kg BW Id). Immobilization stress resulted in a significant inhibition of body weight gain by 45 % and a significant decrease in the tissue weights of thymus and spleen (p < 0.05). The concentrations of blood GOT and GPT were significantly increased in the immobilization-stressed group compared to the control group (p < 0.05). There were no differences in the blood cholesterol levels among groups. Ginseng administration in the immobilization-stressed group tended to reverse the lack of body weight gain and food intake, though not significantly. The ginseng-administered group showed a significant reversal in the stress-induced effect on spleen and thymus weight, increasing the tissue weights by 16% and 20%, respectively, compared to immobilization-stressed group (p<0.05). The plasma corticosterone level was significantly increased in the stressed group by 39 % compared to the control group (p<0.05), but ginseng administration significantly reversed the stress-induced increase in plasma corticosterone by 15 % compared to the immobilization-stressed group. The present study suggests that the anti-stress effect of ginseng is mediated by normalization of stress-induced changes in the circulating hormones and a reversal of tissue weight loss, thereby returning the body to normal homeostasis.
Objectives: This study was designed to investigate whether long-term, low-level exposure to monocyclic aromatic hydrocarbons (MAHs) induced insulin resistance. Methods: The subjects were 110 male workers who were occupationally exposed to styrene, toluene, and xylene. One hundred and ten age-matched male workers who had never been occupationally exposed to organic solvents were selected as a control group. Cytokines, which have played a key role in the pathogenesis of insulin resistance, and oxidative stress indices were measured. Assessment of exposure to MAHs was performed by measuring their ambient levels and their urinary metabolites in exposed workers, and the resulting parameters between the exposed group and non-exposed control groups were compared. Results: There was no significant difference in general characteristics and anthropometric parameters between the two groups; however, total cholesterol, fasting glucose, fasting insulin, and homeostasis model assessment of insulin resistance levels were significantly higher in the exposed group. Phenylglyoxylic acid levels showed significant association with tumor necrosis factor-${\alpha}$, total oxidative status, and oxidative stress index via multiple linear regression analysis. Further, there was a negative correlation between methylhippuric acid levels and total anti-oxidative capacity, and there was a significant relationship between MAHs exposure and fasting glucose levels, as found by multiple logistic regression analysis (odds ratio = 3.95, 95% confidence interval = 1.074-14.530). Conclusion: This study indicated that MAHs increase fasting glucose level and insulin resistance. Furthermore, these results suggested that absorbing the organic solvent itself and active metabolic intermediates can increase oxidative stress and cytokine levels, resulting in the changes in glucose metabolism and the induction of insulin resistance.
Purpose: Coronary artery spasm (CAS) and diabetes mellitus (DM) are implicated in endothelial dysfunction, and insulin resistance (IR) is a major etiological cause of type 2 DM. However, the association between CAS and IR in non-diabetic individuals has not been elucidated. The aim of the present study was to evaluate the impact of IR on CAS in patients without DM. Materials and Methods: A total of 330 eligible patients without DM and coronary artery disease who underwent acetylcholine (Ach) provocation test were enrolled in this study. Inclusion criteria included both hemoglobin A1c <6.0% and fasting glucose level <110 mg/dL without type 2 DM. Patients were divided into quartile groups according the level of homeostasis model assessment of insulin resistance (HOMA-IR): 1Q (n=82; HOMA-IR<1.35), 2Q (n=82; $1.35{\leq}HOMA-IR<1.93$), 3Q (n=83; $1.93{\leq}HOMA-IR<2.73$), and 4Q (n=83; $HOMA-IR{\geq}2.73$). Results: In the present study, the higher HOMA-IR group (3Q and 4Q) was older and had higher body mass index, fasting blood glucose, serum insulin, hemoglobin A1c, total cholesterol, and triglyceride levels than the lower HOMA-IR group (1Q). Also, poor IR (3Q and 4Q) was considerably associated with frequent CAS. Compared with Q1, the hazard ratios for Q3 and Q4 were 3.55 (95% CI: 1.79-7.03, p<0.001) and 2.12 (95% CI: 1.07-4.21, p=0.031), respectively, after adjustment of baseline risk confounders. Also, diffuse spasm and accompanying chest pain during Ach test were more strongly associated with IR patients with CAS. Conclusion: HOMA-IR was significantly negatively correlated with reference diameter measured after nitroglycerin and significantly positively correlated with diffuse spasm and chest pain.
Journal of agricultural medicine and community health
/
v.38
no.3
/
pp.163-173
/
2013
Objectives: There has been an increase in the use of mind-body therapies to control cardiovascular risk factors recently. This trial was designed to determine whether the 'jeol'(Korean Buddhists' prostration) meditation program, as a new mind-body intervention, was effective in managing stress, depression and controlling cardiovascular risk factors in women working at a geriatric hospital. Methods: We conducted a randomized controlled trial to determine whether the 'jeol' meditation program could improve stress, anxiety, depression, and cardiovascular risk factors in women. We randomly assigned 57 participants to the intervention(29 participants) or control(28 participants) group. The subjects in the intervention group participated in a group Jeol meditation program once weekly, and practiced at home. The following variables were assessed: stress(Psychosocial Wellbeing Index), depression(Beck's Depression Inventory), body mass index(BMI), waist circumference, hemoglobin A1c(HbA1c), homeostasis model assessment(HOMA), low-density lipoprotein(LDL) cholesterol, high-density lipoprotein(HDL) cholesterol, and triglyceride were assessed. Results: After the 8-week program, 2 participants from the intervention group and 1 from the control group dropped out. The subjects in the intervention group exhibited decreased scores for stress(t=5.102, p<0.01), depression(t=5.259, p<0.01), BMI(t=2.942, p=0.007), and waist circumference(t=2.582, p=0.016); however these scores did not demonstrate a significant decrease in participants of the control group. The other variables showed no significant difference between the groups. Conclusion: The 'jeol' meditation program evidently reduced stress, anxiety, depression, body weight, and waist circumference in women, which suggests that this program could be employed as a mind-body therapies.
Journal of the Korean Society of Food Science and Nutrition
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v.22
no.4
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pp.381-391
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1993
To evaluate the antioxidizing effect of flavonoid on fish oil and peroxidized fish oil, rats were fed with diets containing 5% corn oil (CO), 5% corn oil and 15% fresh fish oil (FO) or peroxidixed fish oil (PFO) for 4weeks. An half of FO and PFO group rats were injected with 10mg flavonoid (+)-catechin (a day per kg body weight) (FO-C and PFO-C). FO and FO-C group rats showed higher increase in body weight as compared to PFO, PFO-C group rats. Whereas, the opposite result was obtained in case of liver weight increase. In addition, catechin apparently reduced liver weight by 12~17%. Phospholipid, cholesterol, triglyceride and lipid peroxide content in serum and cholesterol, lipid peroxide content in liver and adipose tissue of PFO, PFO-C group rats were significantly higher than those of FO, FO-C one. These results suggested that catechin reduced the synthesis of lipid and protected effectively against lipid peroxidation. In fatty acids profile of neutral lipid and phospholipid, the ratio of polyunsaturated fatty acids (PUFA) versus saturated fatty acids (SFA) in PFO, PFO-C were lower than that of FO or FO-C because of ruduced PUFA. Contrary to our expectation, the enzyme activities of superoxide dismutase(SOD), catalase and glutathione peroxidase (GSH-Px) in rat liver of FO and FO-C group were lower than those of PFO and PFO-C group. These results were quite interesting and might be explained in terms of homeostasis. In case of total lipid in liver, $C_{20:5}$, $C_{22:6}$ fatty acids were decreased in rat fed peroxidized fish oil. In conclusion, catechin was considered to be an antioxidative and hepatoprotective drug and hypolipidemic agent.
We compared antiobese, hypocholesterolemic, antiplatelet and antioxidant effect of 10% green tea powder and 3% green tea extract in rats pair fed 5% cholesterol diets. The final body weight was decreased significantly compared with the control (p < 0.05). Plasma and liver total cholesterol were lower in group of green tea powder or extract, but not statistically different. HDL cholesterol was increased significantly in group of green tea powder compared with the control or green tea extract (p < 0.05). Plasma triglyceride was significantly decreased in group of green tea extract compared with green tea powder, and green tea powder compared with the control respectively (p < 0.05). Liver triglyceride was significantly decreased in group of green tea powder or green tea extract compared with the control (p < 0.01). Platelet aggregations in the maximum and initial slope were not different among groups. Hemolysis was significantly lower in group of green tea powder compared with the control (p < 0.05). Plasma TBARS production was decreased in group of green tea extract compared with the control (p < 0.05). Na passive leak in intact cells was not different, but Na leak in AAPH treated cell was significantly decreased in group of green tea powder than the control (p < 0.05). The leak increase (${\Delta}Na$ Leak) after AAPH treatment was significantly decreased in groups of green tea powder and extract compared with the control (p < 0.05). Isotope excretion after $^{14}C$-cholesterol ingestion was significantly increased in group of green tea extract compared with the control or the green tea powder (p < 0.05). Consumption of green tea in powder or extract may give beneficial effects in weight control and plasma lipid profiles, impeding metabolic syndrome. More studies are needed to clarify what component of green tea and what mechanism are involved in antiobese and hypolipedemic actions of green tea.
This study was conducted to investigate the effect of Makgeolli (MG) and Makgeolli GiGemi (MGG) on blood flow, serum lipid improvement in vivo, and inhibition of angiotensin converting enzyme (ACE) in vitro. The activities of serum AST and ALT were increased by ovariectomy. Serum AST levels were decreased to $77.71{\pm}13.97$ and $74.57{\pm}14.90\;unit/ml$ in the OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($91.14{\pm}12.02\;unit/ml$). Serum ALT levels were decreased to $34.00{\pm}8.41$ and $30.43{\pm}3.60\;unit/ml$ in OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($37.14{\pm}5.40\;unit/ml$). Serum total cholesterol and triglyceride contents decreased in the sham group compared with OVX-control group by ovariectomy. Six weeks feeding of MG and MGG resulted in a decrease to $116.14{\pm}36.02$ and $109.14{\pm}11.55\;mg/dl$ compared to the OVX-control group ($120.43{\pm}8.36\;mg/dl$) in serum total cholesterol, and triglyceride levels were decreased to $52.43{\pm}12.41$ and $47.29{\pm}12.08\;mg/dl$ in the OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($58.57{\pm}5.47\;mg/dl$). The level of HDL-cholesterol in the OVX-control group was significantly reduced to $51.29{\pm}20.49\;mg/dl$ compared to the sham group ($72.29{\pm}10.29\;mg/dl$), but it was increased to $70.71{\pm}19.53$ and $62.00{\pm}20.20\;mg/dl$ with MG and MGG supplementation. Furthermore, the effect of the MG group was higher than the MGG group. Microscopic observation showed that whole blood passed smoothly through the micro channels in the MG and MGG supplemented groups. The platelet aggregation ability of the groups treated with MG and MGG was less than that of the OVX-control group. In vitro assay, the angiotensin converting enzyme (ACE) activity was significantly inhibited by MG and MGG (82.6% and 68.9% inhibition at 0.4 g/ml). These results suggest that the beneficial effects of MG and MGG may be used to improve on the lipid metabolic syndrome of menopausal women. In addition, MG and MGG might improve blood homeostasis mediated activities via antiplatelets and MG and MGG may be used as antihypertensive functional foods and nutraceuticals.
Journal of the Korean Applied Science and Technology
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v.38
no.4
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pp.1117-1128
/
2021
The purpose of the current study was to investigate the effects of 4-week health promotion intervention program consisting of high-intensity aerobic exercise to improve energy consumption and cardiorespiratory capacity, circuit training to strengthen muscular strength and endurance and education for lifestyle changes on the obesity level, physical fitness, insulin resistance and metabolic syndrome among overweight or obese elementary school students. Twenty three overweight or obese children as obese group and 15 normal body weight children as normal group were recruited. The health promotion program consisted of two exercise sessions and one education session, 3days/week in 4-week. Obesity level(body mass index, waist circumference, %body fat), physical fitness(muscular strength, muscular endurance, flexibility, cardiopulmonary fitness), insulin resistance(homeostasis model assessment of insulin resistance) and metabolic syndrome risk factors(blood pressure, fasting glucose, triglycerides, high density lipoprotein cholesterol) were measured. There was not significant decrease in obesity level; however, there were significant improvement in physical fitness, insulin resistance and metabolic syndrome risk factors after program participation among obese children. As a result, through participation in the summer camp consisting mainly of exercise, the improvement of the physical fitness level and the decrease of insulin resistance had an effect on the reduction of the metabolic syndrome frequency.
Purpose: Type 2 diabetes mellitus is a metabolic condition marked by persistent elevated blood sugar levels resulting from insulin resistance. The effective management of diabetes mellitus involves strict regulation of the blood glucose levels. This study examined the effects of Autumn olive (Elaeagnus umbellata Thunb.) berry (AOB) on insulin resistance and hyperglycemia using a type 2 diabetes mellitus animal model. Methods: Eight-week-old C57BL/6J mice were divided into four groups. The control group received a basal diet, while the high-fat, high-sucrose (HFHS) group was fed a HFHS diet containing 27% sucrose and 33% lard for 12 weeks. The low AOB (LAOB) and high AOB (HAOB) groups were offered a HFHS diet with a 0.5% and 1.0% AOB extract, respectively. Results: The HAOB group showed significantly lower epididymal fat pad weight than the HFHS group. The LAOB and HAOB groups showed lower serum glucose levels and homeostasis model assessment for insulin resistance values than the HFHS group, and the HAOB group has lower serum insulin levels than the HFHS group. Supplementation with HAOB decreased serum cholesterol levels significantly compared with the HFHS group. The consumption of LAOB and HAOB reduced the serum triglyceride and hepatic total lipids and triglyceride levels compared to the HFHS group. In addition, LAOB and HAOB consumption in mice fed a HFHS diet increased adenosine monophosphate-activated protein kinase protein expression. Insulin receptor substrate-2 protein expression in the HAOB group was significantly higher than the HFHS group. Conclusion: AOB can alleviate hyperglycemia in type 2 diabetes mellitus partly by mitigating insulin resistance.
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