The effect of corpus luteum on hormonal composition of follicular fluid from different sized follicles and their relationship to serum concentrations in dairy cows

ObjectiveTo investigate the effect of the presence or absence of corpus luteum on hormonal composition of follicular fluid (FF) from different sized follicles and their relationship to serum concentrations in dairy cows.MethodsOvaries were collected from 30 clinically healthy adult female cows (Holstein Friesian) 4–7 years of age with clinically normal reproductive tracts after slaughtering. Blood samples were collected from the jugular vein before slaughter from each cow. The stage of the cycle in the cows was determined postmortem. The ovaries collected from per cow were classified with corpus luteum (CL⁺) and without corpus luteum (CL⁻). FF was aspirated from small (3-5 mm), medium (6-9 mm), and large (10-20 mm) follicles in CL⁺ and CL⁻ ovaries. Serum and FF samples were analyzed for estradiol-17β, progesterone, testosterone, T₃ and T₄ concentrations.ResultsResults demonstrated that the FF concentrations of estradiol-17β, progesterone and testosterone in different sized follicles categories (small, medium and large follicles in CL⁺ and CL⁻ ovaries) were significantly higher (P≤0.05) when compared with the serum. The FF concentrations of estradiol-17β and testosterone in same follicle size categories in CL⁺ and CL⁻ ovaries were also significant (P<0.05). Indeed, concentrations of these hormones in the CL⁻ ovaries were higher than those of the CL⁺ ovaries. However, there was a statistically significant difference between medium and large follicles for progesterone concentration in CL⁺ and CL⁻ ovaries (P<0.05). There was a significant correlation between concentration of hormones in serum and FF with increased follicular diameter.ConclusionsThese results indicated that the levels of hormonal composition in the FF were related to follicular size and interestingly to the presence or absence of a corpus luteum. Indeed, the corpus luteum locally affects neighboring follicular compositions during the luteal phase of the estrous cycle in dairy cows.     

Toll样受体4抑制过氧化物酶体增殖物激活受体γ加重血脂蓄积的分子机制

目的 选取高脂饮食模型大鼠和氧化低密度脂蛋白(oxLDL)暴露下巨噬细胞模型,验证在血脂蓄积过程中Toll样受体4(TLR4)和过氧化物酶体增殖物激活受体γ(PPARγ)的具体干预机制。 方法 健康雄性Wistar大鼠20只,随机分为对照组和高脂组,每组10只。测定各组大鼠总胆固醇、甘油三酯、高密度脂蛋白、低密度脂蛋白水平,采用苏木精-伊红染色检测颈动脉血管内膜中膜厚度比,采用Western blotting法检测TLR4、PPARγ蛋白表达水平。体外培养小鼠巨噬细胞RAW264.7,以oxLDL(50 mg/L)刺激巨噬细胞制备模型,且应用siRNA-TLR4沉默巨噬细胞内的TLR4因子制备TLR4沉默模型,将细胞分为空白组(A组)、oxLDL组(B组)、oxLDL+siRNA组(C组)、oxLDL+siRNA-TLR4组(D组)、oxLDL+siRNA-TLR4+PPARγ激动剂组(E组)、oxLDL+siRNA-TLR4+PPARγ抑制剂组(F组)。采用油红O染色法观察巨噬细胞内血脂蓄积情况,定量检测巨噬细胞内胆固醇含量,采用Western blotting法检测 TLR4、PPARγ蛋白表达水平。 结果 在动物模型实验中,与对照组相比,高脂组总胆固醇、甘油三酯、低密度脂蛋白水平、颈动脉内膜中膜厚度比、TLR4蛋白相对表达含量明显增高(P<0.01),血清高密度脂蛋白水平、PPARγ蛋白相对表达含量明显降低(P<0.01),且TLR4与PPARγ呈负相关性(r=-0.928 1,P<0.001)。在oxLDL暴露巨噬细胞实验中,与A组比较,B、C组巨噬细胞内胆固醇含量、油红O颗粒、光密度值及TLR4蛋白相对表达含量明显增多(P<0.01),PPARγ蛋白相对表达含量明显减少(P<0.05),且B组TLR4与PPARγ呈负相关性(r=-0.986 7,P<0.001)。与B组相比,C组巨噬细胞内胆固醇含量、油红O颗粒、光密度值及TLR4、PPARγ蛋白相对表达含量未见明显改变(P>0.05)。与B组相比,D组巨噬细胞内胆固醇含量、油红O颗粒及光密度值及TLR4蛋白相对表达含量明显减少(P<0.01),PPARγ蛋白相对表达含量明显增多(P<0.05)。与D组相比,E组巨噬细胞内胆固醇含量、油红O颗粒及光密度值明显减少(P<0.01),PPARγ蛋白相对表达含量明显增多(P<0.05),TLR4蛋白相对表达含量未见明显改变(P>0.05)。与D组相比,F组巨噬细胞内胆固醇含量、油红O颗粒及光密度值明显增多(P<0.01),PPARγ蛋白相对表达含量明显减少(P<0.05),TLR4蛋白相对表达含量未见明显改变(P>0.05)。 结论 细胞内的血脂蓄积是动脉粥样硬化形成的机制之一,PPARγ可以抑制巨噬细胞血脂蓄积进而参与动脉粥样硬化调节,是巨噬细胞血脂蓄积过程的保护性因子。而TLR4作为PPARγ上游调控位点,通过抑制PPARγ的表达,加重血脂蓄积的过程,进而干预动脉粥样硬化进程。     

Dialysis Method Alters the Expression of MicroRNA‐33a and Its Target Genes ABCA1, ABCG1 in THP‐1 Macrophages

Atherosclerosis and accompanying cardiovascular disease are the first causes of mortality in patients undergoing maintenance hemodialysis. Anti‐atherosclerotic effects of hemodiafiltration (HDF) have been reported. Our study aimed to investigate the effect of serum derived from a healthy group (n = 23), before and after hemodialysis (HD) therapy (n = 23), and before and after HDF therapy (n = 17) on the expression of microRNA‐33a and its target genes adenosine triphosphate‐binding cassette transporter A1,G1 (ABCA1, ABCG1) in THP‐1 macrophages. Meanwhile, blood lipids and high‐sensitivity C‐reactive protein (hs‐CRP) were measured in these groups. Our data showed that the expression of miRNA‐33a was lower (P < 0.05) and ABCA1 and ABCG1 were higher (P < 0.05) in the healthy group than pre‐HD and pre‐HDF. miR‐33a was significantly decreased (P < 0.05) but ABCA1, ABCG1 was significantly increased (P < 0.05) in post‐HDF compared with pre‐HDF, while these parameters in pre‐ and post‐ HD groups did not show any significant change (P > 0.05). High density lipoprotein cholesterol (HDL‐C) was higher and hs‐CRP was lower in the healthy group than pre‐HD and pre‐HDF groups. Moreover, a significant increase of HDL‐C (P < 0.05) and decrease (P < 0.05) of hs‐CRP was shown in post‐HDF compared with pre‐HDF, but HD appeared to have no significant change in these subjects. HDF therapy can downregulate miR‐33a expression, and then result in ABCA1, ABCG1 upregulation and an increase in circulating HDL‐C, leading to a possible anti‐atherosclerosis effect to some extent.     

Attributional styles and stress-related atherogenic plasma lipid reactivity in essential hypertension

Objective

Hypertension and an atherogenic lipid profile are known risk factors for coronary heart disease (CHD). Hypertensives show greater changes in atherogenic plasma lipids to acute stress than normotensives. In this study, we investigated whether attribution of failure is associated with lipid stress reactivity in hypertensive compared with normotensive men.

Methods

18 normotensive and 17 hypertensive men (mean ± SEM; 45 ± 2.2 years) underwent an acute standardized psychosocial stress task that can be viewed as a situation of experimentally induced failure. We assessed external-stable (ES), external-variable (EV), internal-stable (IS), and internal-variable (IV) attribution of failure and psychological control variables (i.e. extent of depression and neuroticism). Moreover, total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C), and norepinephrine were measured immediately before and several times after stress.

Results

ES moderated TC- and LDL-C-stress reactivity in hypertensives as compared to normotensives (interaction mean arterial pressure [MAP]-by-ES for TC: F = 3.71, p = .015; for LDL-C: F = 3.61, p = .016). TC and LDL-C levels were highest in hypertensives with low ES immediately after stress (p ≤ .039). In contrast, hypertensives with high ES did not differ from normotensives in TC and LDL-C immediately after stress (p's > .28). Controlling for norepinephrine, depression, and neuroticism in addition to age and BMI did not significantly change results. There were no significant associations between lipid baseline levels or aggregated lipid secretion and IS, IV, or EV (p's > .23).

Conclusion

Our data suggest that ES may independently protect from elevated lipid stress reactivity in hypertensive individuals. ES thus might be a protective factor against CHD in hypertension.     

Association between phase angle,anthropometric measurements,and lipid profile in HCV-infected patients

OBJECTIVE:

The objective of this study was to investigate the associations between phase angle, anthropometric measurements, and lipid profile in patients chronically infected with the hepatitis C virus.

METHODS:

A total of 160 consecutive patients chronically infected with the hepatitis C virus and who received treatment at the hepatitis C outpatient unit of our hospital from April 2010 to May 2011 were prospectively evaluated. Bioelectrical impedance analysis, anthropometric measurements, and serum lipid profile analysis were performed.

RESULTS:

Twenty-five patients were excluded. A total of 135 patients with a mean age of 49.8±11.4 years were studied. Among these patients, 60% were male. The phase angle and BMI means were 6.5±0.8° and 26.5±4.8 kg/m², respectively. Regarding anthropometric variables, mid-arm circumference, mid-arm muscle circumference, and arm muscle area had a positive correlation with phase angle. In contrast, when analyzing the lipid profile, only HDL was inversely correlated with phase angle. However, in multiple regression models adjusted for age and gender, only mid-arm circumference (p = 0.005), mid-arm muscle circumference (p = 0.003), and arm muscle circumference (p = 0.001) were associated with phase angle in hepatitis C virus-infected patients.

CONCLUSIONS:

In conclusion, phase angle is positively correlated with anthropometric measures in our study. However, there is no association between phase angle and lipid profile in these patients. Our results suggest that phase angle is related to lean body mass in patients chronically infected with hepatitis C virus.     

Effect of Cholesterol Depletion on Interleukin-8 Production in Human Respiratory Epithelial Cells

Purpose

The lipid entities of cell membranes are components of the immune system and important mediators of inflammation. Despite increasing interest in the function of epithelial cells in inflammation, the role of cholesterol in this process has not been described. Here, we investigated the effect of cholesterol depletion on the inflammatory process in airway epithelial cells via the expression of interleukin (IL)-8 as a marker of inflammation.

Methods

A 549 cells were treated with 0.5% methyl-β-cyclodextrin as a selective cholesterol extractor. The IL-8 level was assessed by enzyme-linked immunosorbent assay and reassessed after cholesterol repletion. Mitogen-activated protein kinase (MAPK) inhibitors were used to determine the upstream signaling pathway for IL-8 production in cholesterol-depleted cells.

Results

We found a relationship between the amount of cholesterol in A 549 cells and inflammation of the airway. IL-8 production was increased in cholesterol-depleted A 549 cells and restored by cholesterol repletion. IL-8 production was decreased by pretreatment with the extracellular signal-regulated kinase (ERK) inhibitor U0126 but not with JNK inhibitor II or the p38 MAPK inhibitor SB202190.

Conclusions

Our findings suggest that inflammatory responses are increased in cholesterol-depleted epithelial cells via the MAPK signaling system, predominantly by the ERK pathway. We conclude that the lipid components of airwayepithelial cells may play a role in the inflammatory process.     

Experimental periodontitis promotes transient vascular inflammation and endothelial dysfunction

Objectives

This study aimed to evaluate the systemic inflammatory response and cardiovascular changes induced by experimental periodontitis in rats.

Design

Experimental periodontitis was induced by placing a cotton ligature around the cervix of both sides of mandibular first molars and maxillary second molars in each male rat. Sham-operated rats had the ligature removed immediately after the procedure. Seven, 14 or 28 days after procedure, the effects of acetylcholine, sodium nitroprusside and phenylephrine were evaluated on blood pressure, aortic rings and isolated and perfused mesenteric bed. The blood was obtained for plasma Interleukin-6 (IL-6), C-reactive protein (CRP) and lipid evaluation. The mesenteric vessels were obtained to evaluate superoxide production and nitric oxide synthase 3 (NOS-3) expression.

Results

Ligature induced periodontitis reduced endothelium-dependent vasodilatation, a hallmark of endothelial dysfunction. This effect was associated with an increase in systemic inflammatory markers (IL-6 and CRP), worsens on lipid profile, increased vascular superoxide production and reduced NOS-3 expression. It is interesting to note that many of these effects were transitory.

Conclusion

Periodontitis induced a transient systemic and vascular inflammation which leads to endothelial dysfunction, an initial step for cardiovascular diseases. Moreover, the animal model of periodontitis used here may represent a valuable tool for studying the relationship between periodontitis and endothelial dysfunction.     

前蛋白转化酶枯草溶菌素9基因多态性的106进展

前蛋白转化酶枯草溶菌素9(PCSK9)是近年来新发现的一种与调节胆固醇代谢密切相关蛋白,属前蛋白转化酶家族。PCSK9可通过调节低密度脂蛋白胆固醇(LDLC)水平进而影响冠状动脉粥样硬化性心脏病、外周血管病、脑血管病、神经系统疾病及糖尿病等疾病的风险。近来研究表明,PCSK9基因多态性位点双向调节胆固醇水平。认识这些多态性位点,对于评估疾病严重性、预后或药物治疗反应有重要临床意义。本文就PCSK9基因多态性及其临床研究进展做一综述。