Dietary cholesterol and oxidised cholesterol: effects on sperm characteristics,antioxidant status and hormonal profile in rats

Present study was designed to compare the potential effects of high serum levels of LDL and oxidised LDL (OxLDL) on spermatogenesis parameters in male Wistar rats. Animals were allocated into three groups and were fed for 14 weeks with normal, cholesterol‐rich and oxidised cholesterol‐rich diets. Blood lipid profile, sex hormones level, as well as sex organs weight were evaluated. The sex organs weight in oxidised cholesterol‐fed group was significantly reduced (P < 0.05). Spermatozoa count in the group with high serum concentration of OxLDL (64 ± 4.2 × 10⁶) was markedly lower (P < 0.01) than that of normal rats (87 ± 4.1 × 10⁶) and rats with high serum level of LDL (90 ± 6.3 × 10⁶). Similarly, the percentage of viable spermatozoa was significantly (P < 0.001) decreased from 78% to 52% by high level of OxLDL in serum. While, nonoxidised LDL did not have suppressive effects on spermatogenesis and organs weight. Consistent with these effects, the serum concentration of sex hormones including FSH (P < 0.001), LH (P < 0.001) and testosterone (P < 0.01) was significantly decreased only in rats with high level of OxLDL but not in rats with high level of nonoxidised LDL. In conclusion, high OxLDL level showed higher destructive effect on reproductive system compared to the high LDL level.     

小而密低密度脂蛋白与急性冠脉综合征及其危险因素的关系

目的　观察急性冠脉综合征 (ACS)患者血浆小而密低密度脂蛋白 (sLDL)水平 ,探讨sLDL与ACS及其危险因素的关系。方法　按病例 对照方法收集ACS患者 2 10例 ,其中急性心肌梗死患者 114例为AMI组 ,不稳定性心绞痛患者 96例为UAP组。选取 2 10名年龄、性别相匹配的健康人作为对照 ,用 2 %～ 16%的非变性聚丙烯酰胺梯度胶电泳法检测sLDL血浆水平 ,观察各组间的sLDL的变化 ;并对sLDL的影响因素采用多元逐步回归进行分析 ,了解ACS的危险因素对sLDL的影响。结果　 ( 1)sLDL在AMI组和UAP组含量明显增高。 ( 2 )多元逐步回归分析结果显示sLDL与TG、性别、腰臀比、高血压史有关 ,校正了这些因素的影响后 ,sLDL与ACS仍有相关性 (r =0 .2 15 ,P<0 .0 0 1)。 ( 3 )与对照组比较 ,sLDL异常者 ,发生ACS的危险性是 3 .85倍 (OR =3 .85 ,95 %的可信区间 2 .40 4～ 6.164 ;χ2 =3 3 .64 ,P <0 .0 0 1)。结论　sLDL水平升高是ACS的重要危险因素 ,使发生ACS的危险性增加。     

Soy isoflavones improve cardiovascular disease risk markers in women during the early menopause

Background

Hormone replacement therapy may be beneficial for cardiovascular disease risk (CVR) in post-menopausal women. Soy isoflavones may act as selective estrogen receptor modulators. The aim of this study was to evaluate whether soy isoflavones had an effect on CVR markers.

A case control study on HDL associated PON1 enzyme level in Northern Indian type 2 diabetes mellitus patients

Aim

To evaluate the serum paraoxonase 1 activity and determine its association with duration in type 2 Diabetes mellitus patients.

老年2型糖尿病患者颅内动脉粥样硬化与亚临床甲状腺功能减退的关系

目的探讨老年2型糖尿病(T2DM)患者颅内动脉粥样硬化与亚临床甲状腺功能减退(SCH)的相关性。方法选择老年T2DM患者404例,其中甲状腺功能正常组(甲功正常组)291例,SCH组113例,比较2组一般情况及各生化指标的差异。分析促甲状腺激素(TSH)与各临床指标的相关性。结果 SCH组女性、颅内动脉粥样硬化、TC、TG、LDL-C、脂蛋白(a)、纤维蛋白原、C反应蛋白、血尿酸、同型半胱氨酸较甲功正常组明显升高,空腹血糖[(6.03±1.32)mmol/L vs(7.61±0.93)mmol/L]、HDL-C[(1.25±0.46)mmol/L vs(1.41±0.49)mmol/L]、D-二聚体[(0.23±0.11)mg/L vs(0.55±0.27)mg/L]显著降低(P<0.05)。TSH、年龄、收缩压、LDL-C、纤维蛋白原、血尿酸、同型半胱氨酸是颅内动脉粥样硬化独立的危险因素,且TSH与纤维蛋白原、TC、TG、LDL-C、脂蛋白(a)、C反应蛋白、血尿酸、同型半胱氨酸呈正相关,与空腹血糖、D-二聚体、HDL-C呈负相关(P<0.05)。结论老年T2DM合并SCH发生颅内动脉粥样硬化风险增加,高TSH是T2DM患者颅内动脉粥样硬化的独立危险因素。     

β_3肾上腺素受体对前蛋白转化酶枯草溶菌素9和低密度脂蛋白受体表达的影响

目的观察激动β3肾上腺素受体(β3-AR)对载脂蛋白E基因敲除(apoE-/-)老年高脂小鼠血脂、肝脏前蛋白转化酶枯草溶菌素9(PCSK9)和LDL受体(LDLR)表达水平的影响。方法选择10周龄雄性C57BL/6小鼠10只(A组)。apoE-/-小鼠40只给予高脂饲料饲养至36周龄,随机分为4组,分别为高脂模型组(B组)、阿托伐他汀阳性药物对照组(C组)、β3-AR激动剂小剂量组(D组)、β3-AR激动剂大剂量组(E组),每组10只,共干预12周。采用Beckman CX7全自动生化分析仪,检测血清TC、TG、VLDL/LDL-C、HDL-C水平,采用Western blot测定肝脏PCSK9和LDLR表达水平。结果与B组比较,C组、D组和E组TC、VLDL/LDL-C明显下降,C组、B组、D组LDLR水平明显上调,C组PCSK9水平明显上调(P<0.05,P<0.01);与C组比较,D组和E组TG、PCSK9水平明显下降,D组LDLR水平明显下降,HDL-C水平明显升高,差异有统计学意义(P<0.05,P<0.01)。结论β3-AR调脂、升高LDLR、降低PCSK9表达水平是其抗动脉粥样硬化的多重作用机制之一。     

Impaired compensatory beta‐cell function and growth in response to high‐fat diet in LDL receptor knockout mice

In this study, we investigated the effect of low density lipoprotein receptor (LDLr) deficiency on gap junctional connexin 36 (Cx36) islet content and on the functional and growth response of pancreatic beta-cells in C57BL/6 mice fed a high-fat (HF) diet. After 60 days on regular or HF diet, the metabolic state and morphometric islet parameters of wild-type (WT) and LDLr−/− mice were assessed. HF diet-fed WT animals became obese and hypercholesterolaemic as well as hyperglycaemic, hyperinsulinaemic, glucose intolerant and insulin resistant, characterizing them as prediabetic. Also they showed a significant decrease in beta-cell secretory response to glucose. Overall, LDLr−/− mice displayed greater susceptibility to HF diet as judged by their marked cholesterolaemia, intolerance to glucose and pronounced decrease in glucose-stimulated insulin secretion. HF diet induced similarly in WT and LDLr−/− mice, a significant decrease in Cx36 beta-cell content as revealed by immunoblotting. Prediabetic WT mice displayed marked increase in beta-cell mass mainly due to beta-cell hypertrophy/replication. Nevertheless, HF diet-fed LDLr−/− mice showed no significant changes in beta-cell mass, but lower islet–duct association (neogenesis) and higher beta-cell apoptosis index were seen as compared to controls. The higher metabolic susceptibility to HF diet of LDLr−/− mice may be explained by a deficiency in insulin secretory response to glucose associated with lack of compensatory beta-cell expansion.     

Biochemical and immunohistochemical changes in delta-9-tetrahydrocannabinol-treated type 2 diabetic rats

The regulation of glucose, lipid metabolism and immunoreactivities of insulin and glucagon peptides by delta-9-tetrahydrocannabinol (Δ⁹-THC) in diabetes were examined in an experimental rat model. Male Sprague-Dawley rats were divided into four groups: (1) control, (2) Δ⁹-THC treated, (3) diabetic, and (4) diabetic + Δ⁹-THC. The type 2 diabetic rat model was established by intraperitoneal (i.p.) injection of nicotinamide (85 mg/kg body weight) followed after 15 min by i.p. injection of streptozotocin (STZ) at 65 mg/kg of body weight. Δ⁹-THC and Δ⁹-THC treated diabetic groups received 3 mg/kg/day of Δ⁹-THC for 7 days. The immunolocalization of insulin and glucagon peptides was investigated in the pancreas using a streptavidin–biotin–peroxidase technique. High density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL), very low density lipoprotein cholesterol (VLDL), triglycerides (TG), total cholesterol (TC) and total protein (TP) levels were measured in serum. Total islet area percent of insulin immunoreactive cells slightly changed in diabetic + Δ⁹-THC rats compared to diabetic animals. However, the area percent of glucagon immunoreactive cells showed a decrease in diabetic + Δ⁹-THC rats compared to that of diabetic animals alone. Serum TC, HDL and LDL levels of diabetes + Δ⁹-THC group showed a decrease compared to the diabetic group. These results indicate that Δ⁹-THC may serve a protective role against hyperlipidemia and hyperglycemia in diabetic rats.