Lipoproteins and Cardiovascular Redox Signaling: Role in Atherosclerosis and Coronary Disease

Increased oxidative stress is associated with hyperandrogenemia in polycystic ovary syndrome evidenced by oxidized lipoproteins stimulating rat ovarian androgen synthesis in vitro

PURPOSE

To determine the relationship between serum total testosterone (TT) levels and oxidative stress indices in patients with polycystic ovary syndrome (PCOS), and to investigate the effect of oxidative stress on androgen synthesis and its mechanism in rat ovarian theca-interstitial (T-I) cells.

METHODS

Clinical, hormonal, metabolic, and oxidative stress parameters were analyzed in a cross-sectional case-control study including 626 patients with PCOS and 296 controls. The effects of oxidized low-density lipoprotein (ox-LDL) and oxidized high-density lipoprotein (ox-HDL) on cell proliferation, TT secretion, and expression of key enzymes involved in testosterone synthesis were evaluated in T-I cells.

RESULTS

Serum TT levels were elevated with an increase in ox-LDL levels, whereas glutathione concentrations were lower in the high-TT subgroup than in the low-TT subgroup. The average ovarian volume and ox-LDL and malondialdehyde levels were significant predictors of TT levels in the multivariate regression models. In a rat ovarian T-I cell model, lipoprotein and oxidized lipoprotein treatments stimulated proliferation and promoted testosterone secretion. The mRNA and protein levels of 17α-hydroxylase were significantly higher in oxidized lipoprotein-treated cells than those in lipoprotein-treated cells. The mRNA levels of cholesterol side chain cleavage enzyme and steroidogenic acute regulatory protein were also significantly higher in ox-HDL-treated cells than in HDL-treated cells.

CONCLUSIONS

Oxidative stress can promote androgen production by up-regulating the expression of testosterone synthesis-related enzymes in vitro and may be an essential factor in elevating serum TT levels in patients with PCOS.

Integrated omics analysis revealed the Tinospora cordifolia intervention modulated multiple signaling pathways in hypertriglyceridemia patients-a pilot clinical trial

Purpose

Hypertriglyceridemia (HTG) is strongly associated with the various types of disease conditions and evolving as epidemics. Hence, it is important to identify molecules that lower the triglyceride and chylomicron levels. Tinospora cordifolia is an illustrious Ayurveda drug, has proved juvenile and immunomodulatory properties.

Methods

Twenty four (24) patients having >499 mg/dL TG and 130-230 mg/dL of cholesterol were randomized and given 100 mL/day (~3.0 g) water extract of T. cordifolia (TCE) for 14 days. Basal parameters were analyzed before and after TC intervention to analyzed primary outcomes. Further, unbiased metabolomics and proteomics profiling was explored to assess the efficacy of TCE in HTG patients.

Results

TCE intervention decreased the levels of triglycerides, and VLDL to 380.45 ± 17.44, and 31.85 ± 5.88, and increased the HDL levels to 47.50 ± 9.05 mg/dL significantly (p < 0.05). Metabolomics analysis identified the significant alteration in 69 metabolites and 72 proteins in plasma of HTG patients. TCE intervention reduced the level of isoprostanes, ROS, BCAA, and fatty acid derivatives, significantly. The annotation databases, Metboanalyst predicted Akt and Rap1 signaling, and ECM-receptor interaction is the most affected in HTG patients. TCE intervention normalized these events by increasing the peroxisome biogenesis and modulating Akt and Rap1 signaling pathway.

Conclusion

T. cordifolia intervention suppresses the baseline in HTG patients. Omics analysis showed that TCE intervention modulates the Akt and Rap signaling, and peroxisome biogenesis to control the cellular switches and signaling pathways. Hence, TCE can be used as a supplement or alternate of standard drugs being used in the management of HTG.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-00985-6.

Oxidative stress promotes hyperandrogenism by reducing sex hormone-binding globulin in polycystic ovary syndrome

OBJECTIVE

To determine the relationships between circulating sex hormone-binding globulin (SHBG) and oxidized low-density lipoprotein (ox-LDL), total oxidant status, total antioxidant capacity, oxidative stress index, malondialdehyde, and the high-density lipoprotein (HDL) inflammatory index in patients with polycystic ovary syndrome (PCOS) and to investigate the effect of oxidative stress on the expression of SHBG and its mechanism in HepG2 cells.

DESIGN

Cross-sectional study.

SETTING

University hospital.

PATIENT(S)

A total of 533 women with PCOS and 292 control women were included.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Circulating SHBG, hormones, and metabolic and oxidative stress indices were determined in all subjects. The effects of ox-LDL and ox-HDL on the mRNA and protein expression of SHBG and related transcription factors were observed in HepG2 cells.

RESULT(S)

The HDL inflammatory index, total oxidant status, oxidative stress index, and malondialdehyde levels were significantly higher in the three PCOS subgroups with different SHBG levels than in the controls. The ox-LDL and total antioxidant capacity were higher in the PCOS subgroups with SHBG levels <75th percentile compared with the controls or the PCOS subgroup with SHBG levels ≥75th percentile. In HepG2 cells, the SHBG concentration in the culture supernatant, the mRNA levels of SHBG and hepatocyte nuclear factor-4α (HNF-4α), and the protein levels of HNF-4α were significantly lower in ox-LDL- and ox-HDL-treated cells than in the control cells and lipoprotein-treated cells.

CONCLUSION(S)

Oxidative stress inhibits the expression and secretion of SHBG by downregulating HNF-4α in vitro and may be an important factor promoting the occurrence of hyperandrogenemia in PCOS.

Current Management Guidelines on Hyperlipidemia: The Silent Killer

Given the high incidence of cardiovascular events in the United States, strict control of modifiable risk factors is important. Pharmacotherapy is helpful in maintaining control of modifiable risk factors such as elevated lipids or hypercholesterolemia. Hypercholesterolemia can lead to atherosclerotic disease which may increase the risk of acute coronary events. Statin therapy has long been a mainstay in the treatment of hypercholesterolemia, but while highly regarded, statin therapy also has side effects that may lead to patient noncompliance. Therefore, various medicines are being developed to manage hypercholesterolemia. This paper will discuss the role that lipids play in the pathophysiology of atherosclerotic disease, review the current lipid management guidelines, and discuss new treatment options that are alternatives to statin therapy.

High-Speed Screening of Lipoprotein Components Using Online Miniaturized Asymmetrical Flow Field-Flow Fractionation and Electrospray Ionization Tandem Mass Spectrometry: Application to Hepatocellular Carcinoma Plasma Samples

This study introduces a high-speed screening method for the quantitative analysis of lipoprotein components in human plasma samples using online miniaturized asymmetrical flow field-flow fractionation and electrospray ionization-tandem mass spectrometry (mAF4-ESI-MS/MS). Using an mAF4 channel, high-density lipoproteins and low-density lipoproteins can be fractionated by size at a high speed (<10 min) and directly fed to ESI-MS/MS for the simultaneous screening of targeted lipid species and apolipoprotein A1 (ApoA1). By employing the heated electrospray ionization probe as an ionization source, an mAF4 effluent flow rate of up to a few tens of microliters per minute can be used, which is adequate for direct feeding to MS without splitting the outflow, resulting in a consistent feed rate to MS for stable MS detection. mAF4-ESI-MS/MS was applied to hepatocellular carcinoma (HCC) plasma samples for targeted quantification of 25 lipid biomarker candidates and ApoA1 compared with healthy controls, the results of which were in statistical agreement with the quantified results obtained by nanoflow ultrahigh performance liquid chromatography-tandem mass spectrometry. Moreover, the present method provided the simultaneous detection of changes in lipoprotein size and the relative amount. This study demonstrated the potential of mAF4-ESI-MS/MS as an alternative high-speed screening platform for the top-down analysis of targeted lipoprotein components in patients with HCC, which is applicable to other diseases that involve the perturbation of lipoproteins.

Body roundness index is a superior indicator to associate with the cardio-metabolic risk: evidence from a cross-sectional study with 17,000 Eastern-China adults

Background

To investigate the ability of body shape index (ABSI), body roundness index (BRI), waist circumference (WC), body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and body adiposity index (BAI) for predicting non-adipose cardio-metabolic risk.

Methods

A total of 17,360 Chinese subjects aged 18–95 years old who escaped cardiovascular disease (CVD) or diabetes were recruited in the cross-sectional study. Anthropometric and biochemical parameters were assessed. Receiver operating characteristic curve (ROC) and multinomial logistic regression were conducted to examine the association of anthropometric indicators with cardio-metabolic risk factors.

Results

The mean age of subjects were 53.7(13.1) years, 41.6 % were males. The areas under the curve (AUC) demonstrated that WC, BMI, WHR, WHtR and BRI were able to predict high cardio-metabolic risk (AUC > 0.70). Meanwhile, multinomial logistic regression showed BRI was significantly associated with high cardio-metabolic risk (OR 3.27, 95% CI 3.01–3.55). The optimal cut-off values of BRI for high cardio-metabolic risk were (< 60 y: 3.49 vs. ≥60 y: 3.46) in males and (< 60 y: 3.47 vs. ≥60 y: 3.60) in females.

Conclusions

WC, BMI WHR, and WHtR were potential obesity indicators in discriminating high cardio-metabolic risk, while BAI or ABSI was not. Moreover, BRI revealed superior predictive capacity and significant association with accumulated cardio-metabolic risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-01905-x.

Effects of resistance exercise training on redox homeostasis in older adults. A systematic review and meta-analysis

BACKGROUND

Resistance exercise training (RET) has proven effective at reducing the risk of chronic disease in older populations, and it appears to regulate redox homeostasis.

AIMS

To determine the effects of RET on redox homeostasis in older people.

STUDY DESIGN

A systematic review and meta-analysis of randomized clinical trials identified by searching MEDLINE, Web of Science, EMBASE, Sportdiscus, LILACS, CENTRAL and CINAHL. We included studies of subjects aged 65 years or older, with or without pathologies, and including RET metrics with quantified molecular oxidation and antioxidant capacity outcomes.

RESULTS

Fifteen studies were included in this review. Agreement between reviewers reached a kappa value of 0.725. There were a total of 614 participants, with an average age of 68.1 years. Five (for molecular oxidation markers) and three (for antioxidant capacity markers) studies included data that quantified the effects of RET on homeostasis redox. The results of the meta-analysis showed that there were no differences in the molecular oxidation markers (SMD = -0.26; 95% CI = -0.57 to 0.05; P = 0.10; I2 = 0%) and antioxidant capacity markers (SMD = 0.53; 95% CI = -0.20 to 1.26; P = 0.16; I2 = 71.5%) in healthy older people after a RET of 8-24 weeks compared to non-intervention.

CONCLUSIONS

Based on a small number of studies of low methodological quality, this systematic review with meta-analysis suggests that RET is not effective at reducing molecular oxidation markers in healthy older people. More research is needed on the effects of RET on redox homeostasis in older people.

PROSPERO REGISTRATION NUMBER

CRD42019121529.

Circadian Rhythms: Will It Revolutionise the Management of Diseases?

The Nobel Prize for Medicine in 2017 was awarded to Michael Young, Michael Rosbash and Jeffrey Hall for their discoveries into the molecular mechanisms controlling circadian rhythms (CR). The aims of this paper were to present the mechanisms behind the CRs and discuss the impact this could have on human health. We argued that further research in this field has the potential to revolutionise healthcare through understanding the influence on the pathogenesis of disease, including in cardiovascular, mental and neurological health, as well as influence on cognitive function. The research has shown that intrinsic CRs have physiological and biochemical influences on the body, which may affect the efficiency of drug absorption due to the altered activity of enzymes. There is strong data to suggest CR disturbances, due to either shift work, sleep disorders or frequent travel between time zones, has negative impact on health. This article aims to summarise the extent of this impact and analyse CRs as a potential therapeutic target, as well as describing the pathophysiology and mechanisms driving the course of disease among people with CR disorders. These new discoveries may revolutionise the way in which treatment is provided in the future with more focus on lifestyle changes to provide treatment and more optimal precision medicine. Pharmaceutical companies and healthcare staff must consider the significant message provided from this data and use the information to optimise drug delivery and treatment provision. The facts of CRs role in healthcare can no longer be ignored.