褪黑素和氨基胍对锰致大鼠肝脏毒性的影响

目的 研究褪黑素(MLT)和氨基胍(AG)对锰致大鼠肝毒性的影响,重点观察肝脏诱导型一氧化氮合酶(iNOS)活性和一氧化氮(NO)、丙二醛(MDA)含量的改变.方法 大鼠按体重随机分成4组,每组10只,第1组为对照组,第2组为单纯染锰组,第3、4组分别为MLT和AG干预组.第1和2组腹腔注射生理盐水,第3、4组分别腹腔注射MLT 5 mg/kg和AG 40 mg/kg;2 h后,第1组皮下注射生理盐水,第2、3、4组分别皮下注射MnCl2溶液200 μmol/kg,注射容量5 ml/kg.每周5次,共4周.4周后,测定血清乳酸脱氢酶(LDH)、丙氨酸氨基转移酶(GPT)以及肝脏一氧化氮合酶(NOS)活性和NO、MDA含量.结果 与对照组比较,单纯染锰组大鼠血清LDH和GPT的活性以及肝脏NO、MDA含量和iNOS活性明显升高,且差异有统计学意义(P<0.01);MLT干预组与单纯染锰组比较,血清LDH和GPT的活性以及肝脏NO、MDA含量和iNOS活性明显下降,且差异有统计学意义(P<0.01);AG干预组与单纯染锰组比较,血清LDH和GPT的活性以及肝脏NO含量和iNOS活性有所下降.结论 锰致肝损伤与肝细胞内iNOS活性升高和产生过多的NO和MDA有关,而且MLT和AG对锰的肝毒性有一定地保护作用.     

Resveratrol Increases Nephrin and Podocin Expression and Alleviates Renal Damage in Rats Fed a High-Fat Diet

Resveratrol is well known for its anti-inflammation and anti-oxidant properties, and has been shown to be effective in alleviating the development of obesity. The purpose of this investigation was to analyze the effect of resveratrol on renal damage in obese rats induced by a high-fat diet (HFD) and its possible mechanisms. Male Sprague-Dawley rats were divided into three groups: control, HFD, and HFD plus resveratrol (treated with 100 mg/kg/day resveratrol). Body weight, serum and urine metabolic parameters, and kidney histology were measured. Meanwhile, the activities of nuclear factor-κB (NF-κB) and superoxide dismutase (SOD), the content of malondialdehyde (MDA), and the protein levels of tumor necrosis factor (TNF-α), monocyte chemotactic protein-1 (MCP-1), nephrin and podocin in kidney were detected. Our work showed that resveratrol alleviated dyslipidemia and renal damage induced by HFD, decreased MDA level and increased SOD activity. Furthermore, the elevated NF-κB activity, increased TNF-α and MCP-1 levels, and reduced expressions of nephrin and podocin induced by HFD were significantly reversed by resveratrol. These results suggest resveratrol could ameliorate renal injury in rats fed a HFD, and the mechanisms are associated with suppressing oxidative stress and NF-κB signaling pathway that in turn up-regulate nephrin and podocin protein expression.     

Hypoglycemic effect of hot-water extract of adzuki (Vigna angularis) in spontaneously diabetic KK-A(y) mice

ObjectiveRecently, we reported that 40% ethanol fraction of hot-water extracts of adzuki (Vigna angularis; EtEx.40) suppressed the postprandial blood glucose level and serum insulin level in normal mice and streptozotocin-induced type 1 diabetic rats. The present study examined the hypoglycemic effect of EtEx.40 on blood glucose, insulin concentrations, organ weight, serum composition, and hepatic lipid content in spontaneously diabetic KK-A^y/Ta Jcl mice, a model for type 2 diabetes.MethodsTo investigate the prevention of type 2 diabetes by EtEx.40 ingestion, 4-wk-old non-diabetic KK-A^y mice were fed an AIN-76 diet containing 5000 mg of EtEx.40/kg of body weight per day (EtEx.40) or an AIN-76 diet without EtEx.40 for 8 wk. Furthermore, to investigate the improvement of type 2 diabetes, 7-wk-old diabetic KK-A^y mice were fed EtEx.40 for 4 wk.ResultsCompared with the control group, EtEx.40 supplementation had a significant effect in lowering blood glucose levels, water intake, serum insulin levels, urinary glucose, urinary microalbumin/creatinine ratio, liver triacylglycerol, and total cholesterol levels. Similar results were observed in 7-wk-old diabetic KK-A^y mice fed EtEx.40 for 4 wk. These effects were also found after short-term administration of EtEx40. Overall, EtEx.40 improved several diabetic symptoms in KK-A^y mice.ConclusionEtEx.40 obtained from hot-water adzuki extracts showed preventive and ameliorative effects on the progression of diabetes in genetically diabetic KK-A^y mice. In the present study, we conclude that the preventive and ameliorative effects by EtEx.40 were due to the modulation of blood glucose levels and the protective effect against oxidative damage in diabetes mellitus.     

刺梨黄酮对实验性糖尿病的预防作用

目的:研究刺梨黄酮对四氧嘧啶致实验性高血糖的预防作用。方法:将小鼠随机分成正常、模型和刺梨黄酮三组,正常与模型两组灌胃蒸馏水,刺梨黄酮组灌胃100mg/kgbw刺梨黄酮。灌胃4w后模型组和刺梨黄酮组腹腔注射四氧嘧啶造型,测血清葡萄糖、胰岛素、血脂、胰脏抗氧化酶活性、脂质过氧化物(MDA)。结果:刺梨黄酮能非常显著地降低造型后小鼠的血清葡萄糖和甘油三酯,升高血清胰岛素。胰脏超氧化物歧化酶(SOD),过氧化氢酶(CAT)活性分别非常显著和显著上升,MDA明显降低。结论:刺梨黄酮能有效保护胰脏免受四氧嘧啶氧化损伤,预防糖尿病。     

曲美他嗪对糖尿病大鼠心肌损害的保护作用

目的探讨曲美他嗪对糖尿病大鼠心肌损害的保护作用。方法60只健康雄性SD大鼠随机分成对照组、糖尿病组、实验A组、实验B组、实验C组,每组各12只。对照组采用标准颗粒饲料喂养。糖尿病组和实验组采用高糖高脂饲料饲养,第6周一次性腹腔注射链脲佐菌素(FTZ 30mg/kg),注射后72 h,筛选血糖水平连续2次高于11.1mmol/L的大鼠,继续原饲料喂养6周,实验A组、B、C组分别腹腔注射10、30和90mg/kg/d曲美他嗪干预6周后,测定5组大鼠血清CK、LDH、TGF-β1、TNF-ɑ、心肌组织ATP、ADP、AMP、MDA、SOD。结果实验期间糖尿病组大鼠的体重增长显著低于对照组和各实验组（P<0.05）,各实验组和对照组比较差异无统计学意义（P>0.05）;糖尿病血清CK、LDH、TGF-β1、TNF-ɑ、心肌组织MDA、ADP含量均显著高于对照组（P<0.05）,心肌SOD活性、ATP、AMP含量显著低于对照组（P<0.05）;实验A、B、C组血清CK、LDH、心肌ADP含量、实验B、C组血清TGF-β1、TNF-ɑ、心肌MDA含量显著低于糖尿病组（P<0.05）,实验A、B、C组的AMP含量、实验B、C组的SOD活性、ATP含量显著高于糖尿病组（P<0.05）。结论曲美他嗪对糖尿病大鼠心肌损害具有明显的保护作用。     

Melatonin reduces oxidative stress induced by chronic exposure of microwave radiation from mobile phones in rat brain

PURPOSE: The aim of the study was to evaluate the intensity of oxidative stress in the brain of animals chronically exposed to mobile phones and potential protective effects of melatonin in reducing oxidative stress and brain injury. MATERIALS AND METHODS: Experiments were performed on Wistar rats exposed to microwave radiation during 20, 40 and 60 days. Four groups were formed: I group (control)- animals treated by saline, intraperitoneally (i.p.) applied daily during follow up, II group (Mel)- rats treated daily with melatonin (2 mg kg(-1) body weight i.p.), III group (MWs)- microwave exposed rats, IV group (MWs + Mel)- MWs exposed rats treated with melatonin (2 mg kg(-1) body weight i.p.). The microwave radiation was produced by a mobile test phone (SAR = 0.043-0.135 W/kg). RESULTS: A significant increase in the brain tissue malondialdehyde (MDA) and carbonyl group concentration was registered during exposure. Decreased activity of catalase (CAT) and increased activity of xanthine oxidase (XO) remained after 40 and 60 days of exposure to mobile phones. Melatonin treatment significantly prevented the increase in the MDA content and XO activity in the brain tissue after 40 days of exposure while it was unable to prevent the decrease of CAT activity and increase of carbonyl group contents. CONCLUSION: We demonstrated two important findings; that mobile phones caused oxidative damage biochemically by increasing the levels of MDA, carbonyl groups, XO activity and decreasing CAT activity; and that treatment with the melatonin significantly prevented oxidative damage in the brain.     

白藜芦醇对大鼠肾氧化损伤保护作用

目的探讨白藜芦醇对高糖高脂饮食大鼠肾氧化损伤的保护作用。方法大鼠分为正常对照组、高糖高脂组、白藜芦醇低、中、高剂量组,13周后处死大鼠,测定血糖血脂、肾组织氧化应激水平、抗氧化酶活性及肾脏过氧化物酶激活受体α(PPARα)、羟甲基戊二酸单酰辅酶A合成酶(HMGCS2)mRNA表达水平。结果高糖高脂饮食13周后,高糖高脂组大鼠体重为(453.00±19.54)g,明显高于正常对照组(368.75±25.24)g和高剂量白藜芦醇组(400.40±30.39)g(t=4.545、2.991,P<0.05);高糖高脂组大鼠肾脏总抗氧化能力(T-AOC)、超氧化物歧化酶(T-SOD)分别为(1.22±0.34)、(2.69±0.13)U/(mg.Pro),明显低于正常对照组的(0.27±0.03)、(2.43±0.07)U/(mg.pro)(t=3.491,P=0.003;t=2.793,P=0.011)。结论高糖高脂饮食大鼠肾内处于明显的氧化应激状态,白藜芦醇对高糖高脂饮食引起的氧化性肾损伤有保护作用。     

蚕蛹油对糖尿病大鼠血糖及氧化应激的影响

目的探讨蚕蛹油对链脲佐菌素所致糖尿病大鼠的血糖及氧化应激的影响。方法 60只雄性SD大鼠按血糖水平分为6组:正常对照组、糖尿病模型组、蚕蛹油高,中,低(7.5,6.0,4.5ml/kgbw.)剂量组,阳性对照组。于每天测饮食量和饮水量,每周末测血糖和体重,3w后测糖化血清蛋白(GSP),并观察糖尿病大鼠肝脏、胰腺组织中丙二醛(MDA)、还原型谷胱甘肽(GSH),总抗氧化能力(T-AOC)的变化。结果 (1)蚕蛹油灌胃治疗后,糖尿病大鼠"三多一少"症状有明显改善;血糖呈现逐渐下降趋势,GSP值亦显著低于模型组,其中蚕蛹油高剂量组降糖作用与阳性对照组相当。(2)糖尿病模型组肝胰组织中MDA含量显著升高,GSH、T-AOC含量均显著降低;蚕蛹油治疗后可以提高肝胰组织中GSH、T-AOC含量,降低MDA含量,与模型组比有显著性差异。结论蚕蛹油具有剂量依赖性地降血糖效果,并且能够提高糖尿病大鼠抗氧化能力。     

Beneficial effects of oligopeptides from marine salmon skin in a rat model of type 2 diabetes

ObjectiveThis study aimed at investigating whether treatment with oligopeptides from marine salmon skin (OMSS) could modulate type 2 diabetes mellitus (T2DM)-related hyperglycemia and β-cell apoptosis in rats induced by high fat diet and low doses of streptozotocin and its therapeutic mechanisms.MethodsGroups of T2DM rats were treated with OMSS or bovine serum albumin (3.0 g/kg/d) for 4 wk and their blood samples, together with those of normal control rats, were collected before and 4 wk after treatment. The levels of fasting blood glucose (FBG) and insulin, serum superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH), tumor necrosis factor-alpha (TNFα), and interferon-gamma (IFNγ) in rats were determined. The islet cell apoptosis and Fas/FasL expression were detected by TUNEL and immunohistochemistry.ResultsIn comparison with control rats, higher levels of FBG and frequency of apoptotic islet cells were detected in the bovine serum albumin group of diabetic rats, accompanied by higher levels of Fas expression in the pancreatic islets, serum TNFα, IFNγ, and MDA, but lower levels of SOD and GSH. However, the levels of FBG and frequency of apoptotic islet cells were significantly reduced in OMSS-treated rats. Lower levels of Fas expression were observed in the pancreatic islets of OMSS-treated rats. Significantly reduced levels of serum TNFα, IFNγ, and MDA, but increased levels of SOD and GSH, were detected in OMSS-treated rats.ConclusionsTreatment with OMSS significantly reduced FBG in diabetic rats. This antidiabetic activity may be mediated by down-regulating T2DM-related oxidative stress and inflammation, protecting the pancreatic β-cells from apoptosis.     

Catechin-rich oil palm leaf extract enhances bone calcium content of estrogen-deficient rats

ObjectivePostmenopausal estrogen deficiency often causes bone density loss and osteoporosis. This study evaluated the effects of an oral administration of oil palm leaf extract (OPL) on bone calcium content and structure, bone density, ash weights, and serum total alkaline phosphatase (T-ALP) of estrogen-deficient ovariectomized (OVX) rats.MethodsFemale Sprague-Dawley rats were divided into five experimental groups: 1) intact (normal control); 2) ovariectomized (OVX control), and OVX rats supplemented with 3) 2% (w/v) green tea (OVX + GT), 4) OPL 150 mg/kg of body weight, or 5) OPL 300 mg/kg of body weight in the drinking water.ResultsAfter 3 mo, the OVX control rats had significantly decreased femur and tibia masses (?5% and ?3%, respectively), ash (?15% and ?10%), calcium content (?0.5% and ?2.7%), and bone density and T-ALP concentrations (?40%) compared with intact rats. The catechin-rich OPL dose dependently increased the OVX bone density and structure, femur and tibia masses (by +8% and +12% respectively), ash (by +30% and +20% respectively), calcium (by +3% and +5%), and T-ALP concentrations (by +76%) compared with the OVX rats. The increases by OPL were higher than that in OVX + GT and control intact rats.ConclusionThe catechin-rich OPL increased the bone mass in estrogen-deficient rats by increasing osteoblast activities to higher levels than in normal rats and those supplemented with GT. This was shown by the modulation of serum T-ALP levels, bone calcium content, total mineral content, and bone histologic structure. The OPL is a potential inexpensive ingredient for protection against osteoporosis and influences bone metabolism by encouraging bone formation.     

Body weight modulates cholesterol metabolism in non-insulin dependent type 2 diabetics

OBJECTIVE: Cholesterol metabolism was studied in 64 subjects with type 2 diabetes who had body weight ranging from normal to obese, to find out whether weight interferes with cholesterol metabolism in diabetes. RESEARCH METHODS AND PROCEDURES: Cholesterol absorption was measured with peroral isotopes and by assaying serum plant sterol and cholestanol to cholesterol ratios, cholesterol synthesis with sterol balance, and measuring serum cholesterol precursor ratios. RESULTS: The study population was divided into normal-weight (body mass index, 24.1 +/- 0.4 kg/m2; mean +/- SEM; n = 20) and obese (31.0 +/- 0.5 kg/m2; n = 44) groups. Despite similar serum cholesterol and blood glucose values, fecal neutral sterol excretion, cholesterol and bile acid synthesis, cholesterol turnover (1649 +/- 78 vs. 1077 +/- 52 mg/d; p < 0.001), and serum cholesterol precursors were higher, and cholesterol absorption % (32 +/- 1 vs. 40 +/- 2%; p < 0.05), serum cholestanol, and plant sterols were lower in the obese vs. the non-obese groups. Serum sex hormone-binding globulin was positively associated with variables of cholesterol absorption, whereas blood glucose, serum insulin, and body mass index were associated with variables of cholesterol synthesis. In multiple stepwise regression analysis, cholesterol absorption percentage (R2 = 24%) and body mass index (R2 = 15%) were the only variables explaining the variability of cholesterol synthesis. DISCUSSION: Body weight, through its entire range, regulates cholesterol metabolism in type 2 diabetes such that with increasing insulin resistance, cholesterol absorption is lowered and cholesterol synthesis increased.     

Resveratrol attenuates steatosis in obese Zucker rats by decreasing fatty acid availability and reducing oxidative stress

Non-alcoholic fatty liver disease (NAFLD) is one of the most common manifestations of chronic liver disease worldwide. The aim of the present study was to assess the effect of resveratrol on liver fat accumulation, as well as on the activity of those enzymes involved in lipogenesis and fatty acid oxidation in fa/fa Zucker rats. A total of thirty rats were assigned to three experimental groups and orally treated with resveratrol for 6 weeks, or without resveratrol (C: control group; RSV15 group: 15?mg/kg body weight per d; RSV45 group: 45?mg/kg body weight per d). Liver histological analysis was performed by microscopy. Levels of hepatic carnitine palmitoyltransferase-Ia (CPT-Ia), acyl-coenzyme A oxidase (ACO), fatty acid synthase, glucose-6-phosphate dehydrogenase and malic enzyme were assessed by spectrophotometry, and acetyl-CoA carboxylase was assessed by radiometry. Commercial kits were used to determine serum TAG, NEFA, total HDL and non-HDL-cholesterol, glycerol, ketonic bodies, glucose, insulin, adiponectin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), hepatic TAG, thiobarbituric acid reactive substrates, GSH (GSSG) and superoxide dismutase. Resveratrol reduced liver weight and TAG content. It did not modify the activity of lipogenic enzymes but it did increase CPT-Ia and ACO activities. NEFA and ALP were reduced in both resveratrol-treated groups. AST/GOT was reduced only by the lowest dose. ALT/GPT, TAG and adiponectin remained unchanged. Resveratrol reduced liver oxidative stress. This study demonstrates that resveratrol can protect the liver from NAFLD by reducing fatty acid availability. Moreover, resveratrol also protects liver from oxidative stress.     

Serum magnesium and type-2 diabetes in African Americans and Hispanics: a New York cohort

OBJECTIVES: The aim of this study was to examine the relationship of serum Mg with stage of diabetes measured by fasting serum glucose in a cohort of 485 African American and Hispanic adults. METHODS: The cross sectional Rosetta study was designed to assess body composition in a multi-racial cohort of healthy adults living in New York City. The data utilized for the current analyses were collected during the years 1990 to 2000. Serum Mg and glucose were measured after a 10-12 hour fast. Dual-energy x-ray absorptiometry was used to measure fat mass (FM) and fat free mass (FFM). RESULTS: The mean age of the cohort was 53 +/- 16 years. Hispanics had significantly lower (p < 0.05) mean serum Mg levels (0.82 +/- 0.07 mmol/L vs. 0.85 +/- 0.07 mmol/L) and FFM (48.8 +/- 10.9 kg vs. 50.9 +/- 10.3 kg) compared to African Americans. In both race/ethnic groups, individuals classified as having diabetes had significantly (p < 0.001) lower serum concentrations of Mg (0.80 +/- 0.07 mmol/L) compared to the normal group (0.84 +/- 0.07 mmol/L). CONCLUSIONS: These results show that in African American and Hispanic adults, those with diabetes have lower serum Mg levels compared to those classified as pre-diabetic or those with normal fasting glucose levels.     

Protective effect of resveratrol on ethanol-induced lipid peroxidation in rats

AIM: Chronic ethanol treatment induces an increase in oxidative stress. As polyphenolic compounds are potent antioxidants, we aimed to examine whether dietary supplementation of resveratrol may attenuate lipid peroxidation, the major end-point of oxidative damage resulting from chronic ethanol administration. METHOD: Three groups of male Wistar rats were used. The first group served as control and received a daily intraperitoneal injection of 0.9% saline. The second group of rats was daily injected with 35% ethanol at 3 g/kg body weight. The third group was given the same dose of ethanol and supplemented with resveratrol (5 g/kg) in the standard diet. Malondialdehyde (MDA), an indicator of oxidative stress, was measured in the liver, heart, brain, and testis. RESULTS: At the end of a 6 weeks treatment period, MDA levels were significantly increased by 51.5, 53.7, 72.7, and 40.5% in the liver, heart, brain, and testis, respectively. However, when ethanol treated rats were given resveratrol the increase in MDA levels was significantly reduced in all organs to nearly those of control rats. CONCLUSION: Resveratrol is able to inhibit the ethanol-induced lipid peroxidation and have protective effect against oxidative injury.     

Differential effects of fish oil and folic acid supplementation during pregnancy in rats on cognitive performance and serum glucose in their offspring

OBJECTIVE: We studied the effect of folic acid and polyunsaturated fatty acid supplementation during pregnancy in Wistar albino rats on cognitive performance and serum glucose concentrations in their pups. METHODS: Pregnant female rats from four groups (n = 6/group) were fed casein diets with 18% protein and 2 mg of folic acid/kg of diet (group I), 12% protein and no folic acid (group II), 12% protein and 8 mg of folic acid/kg of diet (group III), or 12% protein and 70 g of cod liver oil/kg of diet (group IV). All pups were weaned on standard control diet with 18% protein. Cognitive performance, brain fatty acid profile, and serum glucose concentrations were studied in offspring at age 6 mo. RESULTS: There was no significant difference in length of gestation or litter size, but the litter weight for group IV was lower (P = 0.047) than that for group I. After weaning, males in group II had lower (P < 0.05) body weights, but those in group III had weights comparable to those in group I for both sexes. In group IV, body weights were lower beyond 15 wk (P < 0.05). Relative brain weight and cognitive performance were significantly higher (P < 0.05) in group IV males and showed higher levels of brain gamma-linolenic acid. Further, these animals had serum glucose levels comparable to those of control animals at age 6 mo, whereas serum glucose levels were higher in males from groups II (P = 0.01) and III (P = 0.01). CONCLUSION: Fish oil supplementation during pregnancy improved cognitive performance and maintained glucose levels into adulthood, unlike folic acid supplementation, which supported only fetal growth and did not maintain glucose levels.     

The effects of ginkgo biloba extract on tissue adenosine deaminase, xanthine oxidase, myeloperoxidase, malondialdehyde, and nitric oxide in cisplatin-induced nephrotoxicity

This study was carried out to determine if Ginkgo Biloba Extract (GBE or Egb 761) exerts a beneficial effect against cisplatin-induced renal failure in rats. Sprague Dawley rats were divided into four groups. The first group (control) received orally 1 mL/kg/day of 0.9% saline by an oral carrier vehicle on days 1 to 10. The second group was injected with 7 mg/kg cisplatin intraperitoneally (i.p.) on the fourth day, once only. The third group (vit E+cisplatin) was administered 10 mg/kg/day i.p. vit E on 1 to 10 days with one dose of i.p. cisplatin (7 mg/kg) injection on the fourth day. The fourth group (GBE+cisplatin) was given GBE orally at 100 mg/mL/kg started on the first day up to the tenth day with one dose of cisplatin (7 mg/kg) injection on the fourth day. Cisplatin was found to lead a statistically significant increase in plasma BUN and creatinine levels, as well as urine micro total protein (MTP) levels, leading to acute renal failure (ARF) in rats. Renal xanthine oxidase (XO) activities increased in all groups (statistically significant in cisplatin + GBE-treated rats; P < 0.001). Adenosine deaminase (AD) activities were increased in cisplatin-treated rats, and decreased in cisplatin+GBE-treated (P < 0.041) and cisplatin+vit E-treated (P < 0.005) rats, compared to controls. Malondialdehyde (MDA), nitric oxide (NO) levels and myeloperoxidase (MPO) activities were increased in the kidney tissue of cisplatin-treated rats. Vit E improved plasma creatinine and urine MTP levels, together with tissue MDA, NO levels, and MPO activities. But GBE had no statistically significant effect on those parameters. These results indicate that increased XO, AD and MPO activities, as well as MDA and NO levels play a critical role in cisplatin nephrotoxicity. GBE has been shown to protect against cisplatin-induced nephrotoxicity.     

邻苯二甲酸二(2-乙基)己酯青春前期暴露对雌性大鼠性激素水平及卵巢抗氧化系统的影响

目的研究邻苯二甲酸二(2-乙基)己酯(di-(2-ethylhexyl)phthalate,DEHP)青春前期暴露对雌性大鼠性激素水平及卵巢氧化应激指标的影响。方法将40只健康3周龄SPF级雌性SD大鼠按体重随机分为5组,分别为对照(玉米油)组和0.5、5、50、500 mg/kg DEHP暴露组,每组8只。采用经口灌胃方式进行染毒,染毒容量为1 ml/kg,每天1次,连续染毒4周。测定雌性大鼠血清、睾丸氧化应激[丙二醛(MDA)、超氧化物歧化酶(SOD)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、过氧化氢酶(CAT)]指标以及血清、海马性激素[雌二醇、卵泡刺激素(FSH)、黄体生成素(LH)]水平。结果与对照组相比,500 mg/kg DEHP暴露组雌性大鼠卵巢MDA、ACP水平增加,差异均有统计学意义(P0.05);而各剂量DEHP暴露组雌性大鼠卵巢SOD、CAT和AKP的水平均未见明显变化。各剂量DEHP暴露组雌性大鼠血清MDA、SOD、CAT、ACP和AKP的水平与对照组相比,差异均无统计学意义(P0.05)。与对照组相比,仅0.5 mg/kg DEHP暴露组雌性大鼠海马雌二醇水平及5 mg/kg DEHP暴露组雌性大鼠血清雌二醇水平降低,差异均有统计学意义(P0.05)。与对照组相比,仅500 mg/kg DEHP暴露组雌性大鼠血清LH水平升高,差异有统计学意义(P0.05);而各剂量DEHP暴露组雌性大鼠血清FSH水平均未见明显变化。结论 DEHP青春前期暴露会导致雌性大鼠卵巢氧化应激损伤,并易引起青春期性激素分泌紊乱。     

Association Between Magnesium Status,Dietary Magnesium Intake,and Metabolic Control in Patients with Type 2 Diabetes Mellitus

Background: Hypomagnesemia could worsen glycemic control by impairing insulin release and promoting insulin resistance. On the contrary, type 2 diabetes mellitus (T2DM) may induce and/or exacerbate low serum magnesium levels, and this could, in turn, worsen glycemic control of diabetes.

Objective: The aim of this study was to investigate the relationship between serum magnesium level, dietary magnesium intake, and metabolic control parameters in patients with T2DM.

Methods: The study included 119 patients with T2DM (26 male, 93 female; mean age 54.7?±?8.4 years). Serum magnesium level was measured by spectrophotometric method. Magnesium intake was assessed by food frequency questionnaire. Anthropometric measurements were taken. The General Linear Model procedure was applied to determine the relationship of serum magnesium with quantitative variables.

Results: Of the 119 patients, 23.5% of the patients had inadequate magnesium intake (lower than 67% of the recommended daily allowance), and 18.5% had hypomagnesemia. In patients with hypomagnesemia (< 0.75?mmol/l), serum levels of fasting plasma glucose (FPG), postprandial plasma glucose (PPG), and serum glycosylated hemoglobin (HbA1c) were higher compared to patients with normomagnesemia. FPG levels were significantly higher in patients with hypomagnesemia in Model 1 (179.0?±?64.9 vs. 148.7?±?52.0?mg/dl, p?=?0.009) but the significance disappeared in other models. PPG levels were significantly higher in patients with hypomagnesemia in all models (287.9?±?108.4 vs. 226.8?±?89.4?mg/dl, p?=?0.006 for Model 1, p?=?0.027 for Model 2, p?=?0.016 for Model 3). Serum HbA1c levels were significantly higher in patients with hypomagnesemia, and this significance proceeded (8.0?±?1.9% vs. 6.5?±?1.2%, p?=?0.000 for all models). Body fat mass was significantly higher in patients with hypomagnesemia as compared to patients with normomagnesemia in model 3 (35.4?±?9.4?kg, 34.6?±?10.2?kg; p?=?0.034). Dietary magnesium intake was not significantly associated with either metabolic parameters or anthropometric measurements.

Conclusion: Hypomagnesemia in T2DM is directly associated with poor metabolic control. Clinical assessment should, therefore, focus on augmentation of magnesium status and adequate magnesium intake in patients with T2DM.     

Polyphenol-enriched azuki bean (Vina angularis) extract reduces the oxidative stress and prevents DNA oxidation in the hearts of streptozotocin-induced early diabetic rats

Abstract

We examined the changes in the heart of rats at the early stages of streptozotocin (STZ)-induced diabetes, and whether azuki bean extract (ABE) could influence these changes. The experimental diabetic rats received 0 or 40?mg/kg of ABE orally for 4?weeks, whereas the control group rats received distilled water. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and expression of proteins associated with peroxisomal FA β-oxidation as well as oxidative stress markers were examined. The levels of peroxisomal ACOX1 and catalase of the diabetic groups were significantly higher than those in the control group. The levels of p62, phosphorylated-p62 (p-p62) and HO-1 in the STZ group were significantly higher than those in the control group, and the levels of p-p62, HO-1, and 8-OHdG were significantly lower by ABE administration. The STZ-induced early diabetes increases the levels of proteins related to peroxisomal FA β-oxidation and oxidative stress markers in hearts. ABE protects diabetic hearts from oxidative damage.     

Antidiabetic and enzymatic antioxidant properties from methanol extract of Ficus talboti bark on diabetic rats induced by streptozotocin

ObjectiveTo explore scientifically, the type–I anti-diabetic potential of Ficus talboti bark (FTB).MethodsThe HPLC analysis was carried out to identify the phenolic compounds. Effect of two doses of methanol extract of FTB (100 mg/kg and 200 mg/kg body wt.) was orally administered to STZ (Streptozotocin) induced diabetic rats for 21 days. The various parameters were studied including body weight, fasting blood glucose levels, plasma insulin, lipid profile, glycogen content, total protein, serum enzymes levels, and antioxidant activities in normal, treated and diabetic rats. Histochemical analysis of liver and pancreas were also carried out in normal, treated and diabetic rats.ResultsThe HPLC analysis showed the presence of antidiabetic responsible compounds of Rutin, Quercetin and Kaemfeorl. The treatment group with the extract at two dose levels showed a significant increase in the liver, muscle glycogen and serum insulin level and a significant decrease in fasting blood glucose and serum marker enzyme levels. The total cholesterol and serum triglycerides levels were also significantly reduced and the high density lipoprotein and plasma enzymes level was significantly increased upon treatment with the FTB methanol extract. Histochemical study of pancreas also confirmed the biochemical findings. Acute toxicity studies revealed the non-toxic nature of the FTB methanol extract.ConclusionThe results of the experiments presented here suggest that methanol extract of FTB exerts significant antidiabetic and antioxidant effect in STZ induced diabetic rats.