Association between HDL-C levels and menopause: a meta-analysis

Estrogen Induces LCAT to Maintain Cholesterol Homeostasis and Suppress Hepatocellular Carcinoma Development

Hepatocellular carcinoma (HCC) is an aggressive disease that occurs predominantly in men. Estrogen elicits protective effects against HCC development. Elucidation of the estrogen-regulated biological processes that suppress HCC could lead to improved prevention and treatment strategies. Here, we performed transcriptomic analyses on mouse and human liver cancer and identified lecithin cholesterol acyltransferase (LCAT) as the most highly estrogen-upregulated gene and a biomarker of favorable prognosis. LCAT upregulation inhibited HCC in vitro and in vivo and mediated estrogen-induced suppression of HCC in an ESR1-dependent manner. LCAT facilitated high-density lipoprotein cholesterol production and uptake via the LDLR and SCARB1 pathways. Consistently, high HDL-C levels corresponded to a favorable prognosis in HCC patients. The enhanced HDL-C absorption induced by LCAT impaired SREBP2 maturation, which ultimately suppressed cholesterol biosynthesis and dampened HCC cell proliferation. HDL-C alone inhibited HCC growth comparably to the cholesterol-lowering drug lovastatin, and SREBF2 overexpression abolished the inhibitory activity of LCAT. Clinical observations and cross-analyses of multiple databases confirmed the correlation of elevated LCAT and HDL-C levels to reduced cholesterol synthesis and improved HCC patient prognosis. Furthermore, LCAT deficiency mimicked whereas LCAT overexpression abrogated the tumor growth-promoting effects of ovariectomy in HCC-bearing female mice. Most importantly, HDL-C and LCAT delayed the development of subcutaneous tumors in nude mice, and HDL-C synergized with lenvatinib to eradicate orthotopic liver tumors. Collectively, this study reveals that estrogen upregulates LCAT to maintain cholesterol homeostasis and to dampen hepatocarcinogenesis. LCAT and HDL-C represent potential prognostic and therapeutic biomarkers for targeting cholesterol homeostasis as a strategy for treating HCC. Significance: Estrogen mediates the sex differences in hepatocellular carcinoma development by reducing cholesterol biosynthesis through activation of an LCAT/HDL-C axis, providing strategies for improving liver cancer prevention, prognosis, and treatment.

Dyslipidemia and associated factors among adult cardiac patients: a hospital-based comparative cross-sectional study

BACKGROUND

Atherosclerotic vascular diseases are a leading global cause of morbidity and mortality. Dyslipidemia, a major modifiable risk factor for cardiovascular disease, remains poorly understood among adult cardiac patients in in the study area. This study aims to determine the prevalence of dyslipidemia and identify associated factors in this population.

METHODS

Hospital-based comparative cross-sectional study was conducted from May to August 2021. A total of 319 participants (153 cardiac cases, 166 healthy controls, aged ≥ 18) were included in the study. Socio-demographic, anthropometric, behavioral, and clinical data were collected using the WHO STEPS survey instrument through systematic sampling. Overnight fasting blood samples were obtained, and serum lipid profiles were analyzed using a COBAS 6000 analyzer. Data were analyzed with SPSS version 20.0, employing bivariable and multivariable logistic regression. Statistical significance was set at p < 0.05.

RESULTS

The overall prevalence of dyslipidemia, encompassing at least one lipid abnormality, was 80.3% among 256 participants. Among cardiac cases, the prevalence rates were as follows: 72.5% for low HDL-cholesterol, 12.4% for hypercholesterolemia, 9.8% for elevated LDL-cholesterol, and 30.1% for hypertriglyceridemia. In controls, corresponding rates were 69.9%, 9.6%, 7.2%, and 32.5%. Significant factors linked to low HDL- cholesterol were female gender (AOR: 2.8, 95% CI 1.7-4.7) and obesity (AOR: 2.8, 95% CI 1.1-7.5). Abdominal obesity was associated with hypercholesterolemia (AOR: 5.2, 95% CI 1.9-14.3) and elevated LDL-cholesterol (AOR: 5.1, 95% CI 1.6-15.8). High blood pressure, overweight, and abdominal obesity were significantly linked to hypertriglyceridemia (p < 0.05).

CONCLUSION

Dyslipidemia was high among the study participants. Overweight, obesity, central adiposity, and high blood pressure were significantly associated with dyslipidemia in cardiac patients. This alarms the need for lipid profile assessment for patients periodically, with treatment follow-up to monitor any rising patterns and cardiovascular-related risks.

Low circulatory levels of total cholesterol, HDL-C and LDL-C are associated with death of patients with sepsis and critical illness: systematic review, meta-analysis, and perspective of observational studies

BACKGROUND

Mechanistic studies have established a biological role of sterol metabolism in infection and immunity with clinical data linking deranged cholesterol metabolism during sepsis with poorer outcomes. In this systematic review we assess the relationship between biomarkers of cholesterol homeostasis and mortality in critical illness.

METHODS

We identified articles by searching a total of seven electronic databases from inception to October 2023. Prospective observational cohort studies included those subjects who had systemic cholesterol (Total Cholesterol (TC), HDL-C or LDL-C) levels assessed on the first day of ICU admission and short-term mortality recorded. Meta-analysis and meta-regression were used to evaluate overall mean differences in serum cholesterol levels between survivors and non-survivors. Study quality was assessed using the Newcastle-Ottawa Scale.

FINDINGS

From 6469 studies identified by searches, 24 studies with 2542 participants were included in meta-analysis. Non-survivors had distinctly lower HDL-C at ICU admission -7.06 mg/dL (95% CI -9.21 to -4.91, p < 0.0001) in comparison with survivors. Corresponding differences were also seen less robustly for TC -21.86 mg/dL (95% CI -31.23 to -12.49, p < 0.0001) and LDL-C -8.79 mg/dL (95% CI, -13.74 to -3.83, p = 0.0005).

INTERPRETATION

Systemic cholesterol levels (TC, HDL-C and LDL-C) on admission to critical care are inversely related to mortality. This finding is consistent with the notion that inflammatory and metabolic setpoints are coupled, such that the maladaptive-setpoint changes of cholesterol in critical illness are related to underlying inflammatory processes. We highlight the potential of HDL-biomarkers as early predictors of severity of illness and emphasise that future research should consider the metabolic and functional heterogeneity of HDLs.

FUNDING

EU-ERDF-Welsh Government Ser Cymru programme, BBSRC, and EU-FP7 ClouDx-i project (PG).

Substantial Lipid Increases During Menopausal Transition in Korean Middle-Aged Women

BACKGROUND

Adverse lipid profiles are observed in postmenopausal women. However, there is insufficient evidence of the association between lipids and reproductive aging in Korean women. We aimed to characterize lipid changes with respect to timing relative to menopause in Korean middle-aged women.

METHODS

This study included 1,436 premenopausal women who had a natural menopause during the follow-up period (median = 15.76 years) from the Korean Genome and Epidemiology Study (KoGES) Ansan and Anseong cohort. Lipid levels were measured every 2 years, and the magnitudes of annual lipid changes and differences in the changes by premenopausal body mass index were estimated using piecewise linear mixed-effects models.

RESULTS

All lipid levels increased greatly from 3 or 5 years before menopause to 1 year after menopause in all women, regardless of their premenopausal body mass index. During the period, high-density lipoprotein cholesterol (HDL-C) levels increased at 0.42 mg/dL per year (95% confidence interval [CI], 0.29 to 0.55 mg/dL). Nevertheless, non-HDL-C levels simultaneously increased at 3.42 mg/dL per year (95% CI, 3.11 to 3.72 mg/dL), and an annual change in the non-HDL-C to HDL-C ratio was 0.05 (95% CI, 0.04 to 0.06). One year after menopause, changes in all lipid parameters significantly slowed down, except for the non-HDL-C to HDL-C ratio (P < 0.001 for all). The ratio continued to increase until 3 years after menopause, but thereafter, the change leveled off.

CONCLUSION

Women experienced remarkable increases in lipid levels during menopausal transition, highlighting the need for early intervention strategies for cardiovascular disease prevention in women.

Effects of Chromium Supplementation on Lipid Profile: an Umbrella of Systematic Review and Meta-analysis

Dyslipidemia is one of the most well-established modifiable risk factors for cardiovascular disease (CVD) development. Several meta-analyses have revealed the improving effects of chromium on dyslipidemia, while some studies have reported controversial results. This study aimed to summarize meta-analyses of randomized controlled trials (RCTs) that examined the effects of chromium supplementation on lipid profiles in adults. The literature search was conducted using Embase, Scopus, Web of Science, Cochrane Central Library, and PubMed databases with appropriate keywords from the beginning to May 2022. Based on the pooled analysis results, a random-effects model was used to determine the effects of chromium on blood lipid levels. Heterogeneity, publication bias, and sensitivity analysis were also evaluated using standard methods. A total of eight meta-analyses were included in this study. The pooled analysis of eight meta-analyses did not find any significant effect of chromium supplementation on triglycerides (TG) (ES =  - 0.20 mg/dl; 95% CI: - 0.50, 0.10, p = 0.185), total cholesterol (TC) (ES =  - 0.14 mg/dl, 95% CI: - 0.43, 0.16; p = 0.369), low-density lipoprotein cholesterol (LDL-c) (ES =  - 0.08 mg/dl; 95% CI: - 0.19, 0.03; p = 0.142), and high-density lipoprotein cholesterol (HDL-C) levels (ES: 0.05 mg/dl, 95% CI: - 0.05, 0.14, p = 0.312). However, subgroup analysis by the intervention dose suggested that chromium supplementation in doses higher than 500 µg/day could significantly decrease TG. The available evidence proposes no beneficial effects of chromium intervention on blood lipids. As a result, it cannot be used as a single therapy to treat adults with lipid abnormalities.

Lophatherum gracile Bronghiart Suppresses Receptor Activator of Nuclear Factor Kappa-B Ligand-Stimulated Osteoclastogenesis and Prevents Ovariectomy-Induced Osteoporosis

Lophatherum gracile Bronghiart, used in traditional herbal medicine, has many biological properties including antiviral, antipyretic, antitumor, vasorelaxation, and neutrophilic inflammatory effects. However, its modulatory effects on bone metabolism have not been investigated previously. In this study, we examined the effects of a water extract of the leaves of L. gracile (WELG) on osteoclast differentiation and bone loss, and explored its underlying mechanisms. We found that WELG inhibits osteoclastogenesis by suppressing both receptor activator of nuclear factor-κB ligand (RANKL)-induced early activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB)- and RANKL-induced modulation of the positive and negative regulators of osteoclastogenesis in osteoclast precursors. In vivo study demonstrated that WELG protects against bone loss, weight gain, and fat accumulation without affecting uterine atrophy in an ovariectomy-induced postmenopausal osteoporosis mice model. In addition, photochemical analysis of WELG identified active constituents known to have bone-protective effects. Overall, the results of this study suggest that WELG can be a potential candidate for therapy and prevention of postmenopausal osteoporosis.

The Current Status of Research on High-Density Lipoproteins (HDL): A Paradigm Shift from HDL Quantity to HDL Quality and HDL Functionality

The quantity of high-density lipoproteins (HDL) is represented as the serum HDL-C concentration (mg/dL), while the HDL quality manifests as the diverse features of protein and lipid content, extent of oxidation, and extent of glycation. The HDL functionality represents several performance metrics of HDL, such as antioxidant, anti-inflammatory, and cholesterol efflux activities. The quantity and quality of HDL can change during one’s lifetime, depending on infection, disease, and lifestyle, such as dietary habits, exercise, and smoking. The quantity of HDL can change according to age and gender, such as puberty, middle-aged symptoms, climacteric, and the menopause. HDL-C can decrease during disease states, such as acute infection, chronic inflammation, and autoimmune disease, while it can be increased by regular aerobic exercise and healthy food consumption. Generally, high HDL-C at the normal level is associated with good HDL quality and functionality. Nevertheless, high HDL quantity is not always accompanied by good HDL quality or functionality. The HDL quality concerns the morphology of the HDL, such as particle size, shape, and number. The HDL quality also depends on the composition of the HDL, such as apolipoproteins (apoA-I, apoA-II, apoC-III, serum amyloid A, and α-synuclein), cholesterol, and triglyceride. The HDL quality is also associated with the extent of HDL modification, such as glycation and oxidation, resulting in the multimerization of apoA-I, and the aggregation leads to amyloidogenesis. The HDL quality frequently determines the HDL functionality, which depends on the attached antioxidant enzyme activity, such as the paraoxonase and cholesterol efflux activity. Conventional HDL functionality is regression, the removal of cholesterol from atherosclerotic lesions, and the removal of oxidized species in low-density lipoproteins (LDL). Recently, HDL functionality was reported to expand the removal of β-amyloid plaque and inhibit α-synuclein aggregation in the brain to attenuate Alzheimer’s disease and Parkinson’s disease, respectively. More recently, HDL functionality has been associated with the susceptibility and recovery ability of coronavirus disease 2019 (COVID-19) by inhibiting the activity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The appearance of dysfunctional HDL is frequently associated with many acute infectious diseases and chronic aging-related diseases. An HDL can be a suitable biomarker to diagnose many diseases and their progression by monitoring the changes in its quantity and quality in terms of the antioxidant and anti-inflammatory abilities. An HDL can be a protein drug used for the removal of plaque and as a delivery vehicle for non-soluble drugs and genes. A dysfunctional HDL has poor HDL quality, such as a lower apoA-I content, lower antioxidant ability, smaller size, and ambiguous shape. The current review analyzes the recent advances in HDL quantity, quality, and functionality, depending on the health and disease state during one’s lifetime.

Probiotics act as a potent intervention in improving lipid profile: An umbrella systematic review and meta-analysis

Several meta-analysis studies have revealed improving effects of probiotics on lipid profile, while some studies have reported controversial findings. The purpose of present study was to evaluate the efficacy of probiotics on blood lipids. Relevant studies were searched in the international databases, including PubMed, Scopus, EMBASE, Web of Science, and Cochrane Central Library up to August 2021. The pooled results were calculated with the use of a random-effects model to assess the effects of probiotics on blood lipids. Overall, 38 meta-analyses were inclueded in the study. The results indicated that the probiotics supplementation was effective on reduction of total cholesterol (TC) (ES= -0.46 mg/dL; 95% CI: -0.61, -0.30, p < 0.001; I²= 83.8%, p < 0.001), triglycerides (TG) (ES= -0.13 mg/dl; 95% CI: -0.23, -0.04, p = 0.006; I²= 74.7%, p < 0.001), and low-density lipoprotein cholesterol (LDL-C)levels (ES= -0.29 mg/dL; 95% CI: -0.40, -0.19, p < 0.001; I²= 77.8%, p < 0.001). There was no significant effect of probiotics on high-density lipoprotein cholesterol (HDL-C) levels (ES= 0.02 mg/dl; 95% CI: -0.04, 0.08, p = 0.519; I²= 72.5%, p= <0.001). The results of present umbrella meta-analysis strongly support supplementation with probiotics as an influential intervention for improving lipid profile.

Raloxifene has favorable effects on the lipid profile in women explaining its beneficial effect on cardiovascular risk: A meta-analysis of randomized controlled trials

There is robust evidence that the appropriate treatment of dyslipidaemia substantially reduces cardiovascular disease-related morbidity and mortality. Raloxifene is a selective oestrogen receptor modulator that also interferes with the lipid metabolism and may be of aid in the management of lipid abnormalities in females. Therefore, we conducted a systematic review and meta-analysis of the available randomized clinical trials (RCTs) exploring the effect of raloxifene on the lipid profile in women. The Scopus, Web of Science, PubMed/Medline and EMBASE databases were systematically and independently searched by two assessors from inception until 20 November 2020 without time and language restrictions. The overall findings were generated from 30 eligible RCTs. As compared to controls, raloxifene resulted in a significant elevation of the high-density lipoprotein-cholesterol (HDL-C) (WMD: 2.41 mg/dL, 95% CI: 0.84-3.97, P = 0.003) and a significant reduction of the total cholesterol (TC) (WMD:-14.84 mg/dL, 95% CI: -20.37 to -9.317, P = 0.000) and of the low-density lipoprotein-cholesterol (LDL-C) (WMD: -17 mg/dL, 95% CI: -25.77, -8.22, P = 0.000). In the stratified analysis, a significant decrease of serum triglycerides (TG) (WMD: -22.06 mg/dL) was achieved in the RCTs with a duration of ≤ 26 weeks (WMD -8.70 mg/dL) and with baseline TG concentrations of ≥ 130 mg/dL (WMD: -23.02 mg/dL). In conclusion, raloxifene treatment can increase HDL-C and lower LDL-C and TC. In terms of TG, a significant decrease can be observed if the administration of raloxifene lasts ≤ 26 weeks and if the baseline TG concentrations are ≥ 130 mg/dL.