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1.
Sci Rep ; 14(1): 8407, 2024 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600230

RESUMO

Elevated remnant cholesterol (RC) is considered a risk factor for atherosclerotic cardiovascular disease, but the evidence on this association applies to the Chinese population with hypertension is limited. We aimed to explore the association between RC levels and carotid plaque in old adults with hypertension. 8523 hypertensive patients aged ≥ 60 years with serum lipids and carotid ultrasonography data were included in this community-based screening. Fasting RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus low-density lipoprotein cholesterol (LDLC). The associations of RC levels with carotid plaque risk were evaluated using Logistic regression and restricted cubic spline models. Carotid plaque was screened in 4821 (56.56%) subjects. After multivariable-adjusted, RC was significantly related to carotid plaque [Odd ratio (OR)] = 1.043 per 0.1 mmol/L increase, 95% confidence interval (CI): 1.030-1.056). The highest versus the lowest quartile of RC was 1.928 (1.673-2.223) for carotid plaque. A nonlinear association was found between serum RC levels and the risk of carotid plaque (P for nonlinearity < 0.001). Moreover, an RC > 0.78 mmol/L differentiated patients at a higher risk of carotid plaque compared to those at lower concentrations, regardless of whether LDLC was on target at 2.59 mmol/L. In old adults with hypertension, elevated RC was positively associated with carotid plaque, independent of LDLC and other conventional risk factors.


Assuntos
Aterosclerose , Hipercolesterolemia , Hipertensão , Placa Aterosclerótica , Adulto , Humanos , Colesterol , Hipertensão/complicações , Hipertensão/epidemiologia , Artérias Carótidas , Aterosclerose/complicações , Fatores de Risco , Hipercolesterolemia/complicações , China/epidemiologia
2.
Atherosclerosis ; 393: 117554, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38663275

RESUMO

BACKGROUND AND AIMS: Long noncoding RNAs (lncRNAs) play important roles in the progression of atherosclerosis. In this study, we identified an uncharacterized lncRNA, Liver Expressions by PSRC1 Induced Specifically (LEPIS). This study aimed to clarify the mechanism though which LEPIS affects atherosclerosis (AS). METHODS: The expression of LEPIS and its potential target, tropomodulin 4 (TMOD4), was increased in the livers of ApoE-/- mice fed a high-fat diet (HFD). An ApoE-/- mouse model in which LEPIS or TMOD4 was overexpressed in the liver was established. The plaque load in the aorta was assessed, plasma was collected to measure blood lipid levels, and the liver was collected to study cholesterol metabolism. RESULTS: We found that both LEPIS and TMOD4 increased the AS burden and reduced hepatic cholesterol levels. A further study revealed that LEPIS and TMOD4 affected the expression of genes related to hepatic cholesterol homeostasis, including proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein receptor (LDLR), which are closely related to hypercholesterolemia. Mechanistically, human antigen R (HuR), an RNA-binding protein (RBP), was shown to be critical for the regulation of TMOD4 by LEPIS. Furthermore, we found that verexpression of LEPIS promoted the shuttling of HuR from the nucleus to the cytoplasm, enhanced the stability of TMOD4 mRNA, and in turn promoted the expression of TMOD4. In addition, TMOD4 was found to affect intracellular cholesterol levels through PCSK9. CONCLUSIONS: These results suggest that the LEPIS-HuR-TMOD4 axis is a potential intervention target for dysregulated hepatic cholesterol homeostasis and AS and may provide the basis for further reductions in the circulating LDL-C concentration and arterial plaque burden.

3.
J Breath Res ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663377

RESUMO

In the breath research community's search for volatile organic compounds that can act as non-invasive biomarkers for various diseases, hundreds of endogenous volatiles have been discovered. Whilst these systemic chemicals result from normal and abnormal metabolic activities or pathological disorders, to date very few are of any use for the development of clinical breath tests that could be used for disease diagnosis or to monitor therapeutic treatments. The reasons for this lack of application are manifold and complex, and these complications either limit or ultimately inhibit the analytical application of endogenous volatiles for use in the medical sciences. One such complication is a lack of knowledge on the biological origins of the endogenous volatiles. A major exception to this is isoprene. Since 1984, i.e., for forty years, it has been generally accepted that the pathway to the production of human isoprene, and hence the origin of isoprene in exhaled breath, is through cholesterol biosynthesis via the mevalonate (MVA) pathway within the liver. However, various studies between 2001 and 2012 provide compelling evidence that human isoprene is produced in skeletal muscle tissue. A recent multi-omic investigation of genes and metabolites has revealed that this proposal is correct by showing that human isoprene predominantly results from muscular lipolytic cholesterol metabolism. Despite the overwhelming proof for a muscular pathway to isoprene production in the human body, breath research papers still reference the hepatic MVA pathway. The major aim of this perspective is review the evidence that leads to a correct interpretation for the origins of human isoprene, so that the major pathway to human isoprene production is understood and appropriately disseminated. This is important, because an accurate attribution to the endogenous origins of isoprene is needed if exhaled isoprene levels are to be correctly interpreted and for assessing isoprene as a clinical biomarker.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38664125

RESUMO

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is the most common cause of death in Europe. Although the 2019 European Society of Cardiology/European Atherosclerosis Society Guidelines for the management of dyslipidaemias claim a target low-density lipoprotein cholesterol (LDL-C) value of <55 mg/dL for very high-risk patients by use of lipid-lowering therapy (LLT) and lifestyle adaptations, the target level achievement is not satisfactory. We examined LLT use in ASCVD patients exceeding LDL-C target levels at admission and its adaptations at discharge. METHODS AND RESULTS: Between January 2017 and February 2020, 1091 patients with LDL-C >100 mg/dL and ASCVD defined as diagnosis of angina pectoris (AP, n = 179), acute myocardial infarction (AMI, n = 317), chronic ischemic heart disease (CHD, n = 195), or peripheral artery disease (PAD, n = 400) were extracted from hospital records. LLT use on admission and discharge as well as recommendations on lifestyle and nutrition were analysed. On admission, 51% of the patients were not taking LLT. At discharge, 91% were prescribed statins and 87% were advised on lifestyle adaptation and/or pharmacological treatment. High-intensity statin use at discharge was present in 63% of the AP-group, 92% of the AMI-group, 62% of the CHD-group and 71% of the PAD-group. Ezetimibe was present in 16% and proprotein convertase subtilisin/kexin 9 inhibitors (PCSK9i) in 1%. However, of those on high-intensity statin, 25% remained on insufficient statin dosage. CONCLUSION: Switch to high-intensity statins and use of ezetimibe and PCSK9i was low in chronic ASCVD patients. Even though statin intake was high in high-risk patients, target levels were still not reached.

5.
J Clin Lipidol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38664184

RESUMO

BACKGROUND: This joint expert review by the Obesity Medicine Association (OMA) and National Lipid Association (NLA) provides clinicians an overview of the pathophysiologic and clinical considerations regarding obesity, dyslipidemia, and cardiovascular disease (CVD) risk. METHODS: This joint expert review is based upon scientific evidence, clinical perspectives of the authors, and peer review by the OMA and NLA leadership. RESULTS: Among individuals with obesity, adipose tissue may store over 50% of the total body free cholesterol. Triglycerides may represent up to 99% of lipid species in adipose tissue. The potential for adipose tissue expansion accounts for the greatest weight variance among most individuals, with percent body fat ranging from less than 5% to over 60%. While population studies suggest a modest increase in blood low-density lipoprotein cholesterol (LDL-C) levels with excess adiposity, the adiposopathic dyslipidemia pattern most often described with an increase in adiposity includes elevated triglycerides, reduced high density lipoprotein cholesterol (HDL-C), increased non-HDL-C, elevated apolipoprotein B, increased LDL particle concentration, and increased small, dense LDL particles. CONCLUSIONS: Obesity increases CVD risk, at least partially due to promotion of an adiposopathic, atherogenic lipid profile. Obesity also worsens other cardiometabolic risk factors. Among patients with obesity, interventions that reduce body weight and improve CVD outcomes are generally associated with improved lipid levels. Given the modest improvement in blood LDL-C with weight reduction in patients with overweight or obesity, early interventions to treat both excess adiposity and elevated atherogenic cholesterol (LDL-C and/or non-HDL-C) levels represent priorities in reducing the risk of CVD.

6.
Int J Cardiol Cardiovasc Risk Prev ; 21: 200261, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623144

RESUMO

Background: Despite recent guidelines appropriate lipid-lowering treatment (LLT) remains suboptimal in everyday clinical practice. Aims: We aimed to describe clinical practice of use of LLT for at least high CV risk populations in a Hellenic real-world setting and assess how this relates to the European Society of Cardiology treatment guidelines. Methods: We analyzed data from a retrospective cohort study of the National Registry of patients with dyslipidemia between 1/7/2017 and 30/6/2019 who were at least of high CV risk and filled a dual or triple lipid-lowering treatment (dLLT, tLLT) prescription. The primary outcomes of interest of this analysis were to report on the patterns of LLT use in at least high CV risk patients. Results: A total of 994,255 (45.4% of Greeks on LLT) were of at least high CV risk and 120,490 (5.5%) were on dLLT or tLLT. The percentage of patients with reported statin intolerance ranged from 2 to 10%. While persistence was reported to be satisfactory (>85% for both dLLT or tLLT), adherence was low (ranging between 14 and 34% for dLLT). In 6-month intervals, the percentage of patients achieving a low-density lipoprotein cholesterol (LDL-C) target below 100 md/dL ranged from 20% to 23% for dLLT and 34%-37% for tLLT. Conclusions: The prevalence of at least high CV risk patients among patients receiving LLT in Greece is substantial. Despite the high persistence and probably due to the low adherence to treatment, LDL-C remains above targets in more than two thirds of patients.

7.
Sci Rep ; 14(1): 9037, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641617

RESUMO

We aimed to identify different trajectories of remnant cholesterol (RC) and investigate the association of RC trajectories with vascular endothelial function and atherosclerosis progression in a longitudinal cohort of the Chinese population. A total of 521 participants were included in the flow-mediated vasodilation (FMD) subcohort study, and 7775 participants were included in the brachial-ankle pulse wave velocity (baPWV) subcohort study. All participants had ≥ 3 medical examinations during the 10-year follow-up period. In the FMD subcohort study, three distinct RC trajectories were identified according to the RC range and changing pattern over time: "low" (57.58%), "moderate" (30.90%) and "high" (11.52%). The proportion of the three groups with vascular endothelial dysfunction (FMD < 7.0%) was 20.00%, 39.75% and 60.00% respectively. Taking the low group as a reference, participants in the moderate and high groups had over 1.88 and 2.94 times the odds of vascular endothelial dysfunction (P = 0.048). In the baPWV subcohort study, three distinct RC trajectories were also identified: "low" (54.29%), "moderate" (38.97%) and "high" (6.74%). The proportion of the three groups with atherosclerosis (baPWV > 1400 cm/s) was 38.79%, 51.26% and 59.01% respectively. Taking the low group as a reference, participants in the moderate and high groups had over 1.46 and 2.16 times the odds of atherosclerosis (P < 0.001). The findings indicated that distinct RC trajectories are significantly associated with vascular endothelial function and atherosclerosis. Regular monitoring to identify persistent increases in RC may be more helpful in identifying individuals with a high risk of cardiovascular disease.


Assuntos
Aterosclerose , Rigidez Vascular , Adulto , Humanos , Estudos Longitudinais , Índice Tornozelo-Braço , Endotélio Vascular , Análise de Onda de Pulso , Aterosclerose/epidemiologia , Colesterol , China/epidemiologia , Fatores de Risco
8.
Lipids Health Dis ; 23(1): 114, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643132

RESUMO

Disturbances in cholesterol homeostasis have been associated with ASD. Lipid rafts are central in many transmembrane signaling pathways (including mTOR) and changes in raft cholesterol content affect their order function. Cholesterol levels are controlled by several mechanisms, including endoplasmic reticulum associated degradation (ERAD) of the rate limiting HMGCoA reductase. A new approach to increase cholesterol via temporary ERAD blockade using a benign bacterial toxin-derived competitor for the ERAD translocon is suggested.A new lock and key model for cholesterol/lipid raft dependent signaling is proposed in which the rafts provide both the afferent and efferent 'tumblers' across the membrane to allow 'lock and key' receptor transmembrane signals.


Assuntos
Transtorno do Espectro Autista , Humanos , Colesterol/metabolismo , Degradação Associada com o Retículo Endoplasmático , Microdomínios da Membrana/metabolismo
9.
Lipids Health Dis ; 23(1): 115, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643148

RESUMO

BACKGROUND: The triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and triglyceride-glucose (TyG) index are novel indexes for insulin resistance (IR). We aimed to evaluate associations of TG/HDL-C and TyG with arterial stiffness risk. METHODS: We enrolled 1979 participants from the Rural Chinese Cohort Study, examining arterial stiffness by brachial-ankle pulse wave velocity (baPWV). Logistic and linear regression models were employed to calculate effect estimates. For meta-analysis, we searched relevant articles from PubMed, Embase and Web of Science up to August 26, 2023. The fixed-effects or random-effects models were used to calculate the pooled estimates. We evaluated dose-response associations using restricted cubic splines. RESULTS: For cross-sectional studies, the adjusted ORs (95%CIs) for arterial stiffness were 1.12 (1.01-1.23) and 1.78 (1.38-2.30) for per 1 unit increment in TG/HDL-C and TyG. In the meta-analysis, the pooled ORs (95% CIs) were 1.26 (1.14-1.39) and 1.57 (1.36-1.82) for per 1 unit increment of TG/HDL-C and TyG. Additionally, both TG/HDL-C and TyG were positively related to PWV, with ß of 0.09 (95% CI 0.04-0.14) and 0.57 (95% CI 0.35-0.78) m/s. We also found linear associations of TG/HDL-C and TyG with arterial stiffness risk. CONCLUSIONS: High TG/HDL-C and TyG were related to increased arterial stiffness risk, indicating TG/HDL-C and TyG may be convincing predictors of arterial stiffness.


Assuntos
Resistência à Insulina , Rigidez Vascular , Humanos , Glucose , Triglicerídeos , Estudos de Coortes , Índice Tornozelo-Braço , Rigidez Vascular/fisiologia , HDL-Colesterol , Estudos Transversais , Análise de Onda de Pulso , Resistência à Insulina/genética , Glicemia , Biomarcadores
10.
J Chromatogr A ; 1722: 464865, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598891

RESUMO

Oxysterols and cholesterol precursors are being increasingly investigated in humans and laboratory animals as markers for various diseases in addition to their important functions. However, the quantitative analysis of these bioactive molecules is obstructed by high structural similarity, poor ionization efficiency and low abundance. The current assay methods are still cumbersome to be of practical use, and their applicability in different bio-samples needs to be evaluated and optimized as necessary. In the present work, chromatographic separation conditions were carefully studied to achieve baseline separation of difficult-to-isolate compound pairs. On the other hand, an efficient sample purification method was established for colon tissue samples with good recoveries of sterols, demonstrating negligible autoxidation of cholesterol into oxysterols. The developed UPLC-APCI-MS/MS method was thoroughly validated and applied to measure oxysterols and cholesterol precursors in colon tissue of dextran sulfate sodium (DSS)-induced mouse colitis models, and it is expected to be successfully applied to the quantitative determination of such components in other tissue samples.


Assuntos
Colesterol , Colite Ulcerativa , Colo , Sulfato de Dextrana , Modelos Animais de Doenças , Oxisteróis , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Camundongos , Oxisteróis/análise , Colo/química , Colo/metabolismo , Colite Ulcerativa/metabolismo , Colesterol/análise , Colesterol/análogos & derivados , Cromatografia Líquida/métodos , Camundongos Endogâmicos C57BL , Masculino , Cromatografia Líquida de Alta Pressão/métodos , 60705
11.
Indian Heart J ; 76 Suppl 1: S73-S74, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38599728

RESUMO

Evidence from the existing literature suggests that exercise has positive effects for prevention and treatment of cardiovascular diseases by reducing risk factors such as elevated blood lipids. Based on clinical and observational clinical trials, it is well established that increased physical activity and regular exercise has a favourable impact on blood lipids and lipoprotein profiles. Exercise training significantly decreases blood triglycerides concentration and increases high density lipoprotein cholesterol levels. Though the Indian data depicting the effect of exercise on lipids is scarce, exercise directly improves "atherogenic dyslipidaemia" which is frequently present among Indians i.e. HDL-C is increased, TG is reduced and LDL-C particle size is improved. While drug therapy is key to the treatment of dyslipidaemia, lifestyle alterations such as exercise should continue to be actively promoted and encouraged by clinicians. Exercise is a low cost, non pharmacological therapeutic lifestyle change that is of value to lipid metabolism and cardiovascular fitness.


Assuntos
Dislipidemias , Exercício Físico , Humanos , HDL-Colesterol , Dislipidemias/terapia , Lipídeos , Lipoproteínas , Triglicerídeos , Ensaios Clínicos como Assunto , Estudos Observacionais como Assunto
12.
Lipids Health Dis ; 23(1): 121, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659020

RESUMO

BACKGROUND: Previous studies have shown that the relationship between high-density lipoprotein cholesterol (HDL-C) and stroke is controversial, and the association between the platelet/high-density lipoprotein cholesterol ratio (PHR), a novel marker for inflammation and hypercoagulability states, and stroke has not been established. METHODS: This study presents an analysis of cross-sectional data from the 2005-2018 National Health and Nutrition Examination Survey (NHANES). Stroke history, HDL-C levels, and platelet counts were obtained during cross-sectional surveys. The PHR was calculated as the ratio of the number of platelets to HDL-C concentration. Weighted logistic regression was used to assess the associations of HDL-C and the PHR with stroke. Nonlinearity of this relationship was determined through restricted cubic splines (RCSs) and two-piecewise linear regression for identifying inflection points. Furthermore, Cox regression was utilized to prospectively analyze the associations of the PHR and HDL-C concentration with cardiovascular disease (CVD) mortality in stroke survivors. RESULTS: A total of 27,301 eligible participants were included in the study; mean age, 47.28 years and 50.57% were female, among whom 1,040 had a history of stroke. After full adjustment, the odds ratio (OR) of stroke associated with a per standard deviation (SD) increase in the PHR was estimated at 1.13 (95% confidence interval (CI): 1.03 - 1.24, P = 0.01), and the OR of stroke associated with a per SD increase in HDL-C was 0.95 (95% CI: 0.86-1.05, P = 0.30). The RCS indicated a nonlinear relationship for both variables (PPHR = 0.018 and PHDL-C = 0.003), and further piecewise linear regression identified inflection points at PHR = 223.684 and HDL-C = 1.4 mmol/L. Segmental regression indicated that in the PHR ≥ 223.684 segment, the estimated OR of stroke associated with a per-SD increase in the PHR was 1.20 (95% CI: 1.09 - 1.31, P < 0.001), while the association of stroke with HDL-C was not significant before or after the inflection point (P > 0.05). Furthermore, Cox regression and RCS showed that a per-SD increase in the PHR was linearly associated with a greater risk of CVD mortality among stroke survivors (HR: 1.14, 95% CI: 1.06 - 1.22, P < 0.001; nonlinear, P = 0.956), while HDL-C was not significantly associated with CVD mortality. CONCLUSION: The association between the PHR and stroke incidence exhibited a significant threshold effect, with an inflection point at 223.684. A PHR exceeding 223.684 was positively associated with stroke, while the association between HDL-C and stroke was not significant. Additionally, the PHR was positively and linearly associated with CVD mortality among stroke survivors.


Assuntos
Plaquetas , HDL-Colesterol , Inquéritos Nutricionais , Acidente Vascular Cerebral , Humanos , Feminino , HDL-Colesterol/sangue , Masculino , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/epidemiologia , Pessoa de Meia-Idade , Estudos Transversais , Plaquetas/metabolismo , Plaquetas/patologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/sangue , Autorrelato , Adulto , Idoso , Fatores de Risco , Contagem de Plaquetas , Razão de Chances
13.
Nutr J ; 23(1): 45, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644466

RESUMO

BACKGROUND: Breast cancer is the most common malignancy in women worldwide. The relationship between remnant cholesterol (RC) and the prognosis of patients with breast cancer has not been clearly reported. This study investigated the prognostic value of RC in predicting mortality in patients with breast cancer. METHODS: This study prospectively analysed 709 women patients with breast cancer from the Investigation on Nutrition Status and Clinical Outcome of Common Cancers (INSCOC) project. Restricted cubic splines were used to analyse the dose-response relationship between RC and breast cancer mortality. The Kaplan-Meier method was used to evaluate the overall survival of patients with breast cancer. A Cox regression analyses was performed to assess the independent association between RC and breast cancer mortality. Inverse probability of treatment weighting (IPTW) using the propensity score was used to reduce confounding. Sensitivity analysis was performed after excluding patients with underlying diseases and survival times shorter than one year. RESULTS: A linear dose-response relationship was identified between RC and the risk of all-cause mortality in patients with breast cancer (p = 0.036). Kaplan-Meier survival analysis and log-rank test showed that patients with high RC levels had poorer survival than those with low RC levels (p = 0.007). Univariate and multivariate Cox regression analyses showed that RC was an independent risk factor for mortality in women patients with breast cancer. IPTW-adjusted analyses and sensitivity analyses showed that CR remained a prognostic factor. CONCLUSIONS: RC is an independent risk factor for the prognosis of patients with breast cancer, and patients with higher RC levels have poorer survival.


Assuntos
Neoplasias da Mama , Colesterol , Lipoproteínas , Humanos , Feminino , Neoplasias da Mama/mortalidade , Colesterol/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , Prognóstico , Adulto , Estimativa de Kaplan-Meier , Fatores de Risco , Modelos de Riscos Proporcionais , Biomarcadores/sangue , Triglicerídeos/sangue , Idoso
14.
Pharmacol Res Perspect ; 12(3): e1197, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38644590

RESUMO

Human cytochrome P450 3A4 (CYP3A4) is a drug-metabolizing enzyme that is abundantly expressed in the liver and intestine. It is an important issue whether compounds of interest affect the expression of CYP3A4 because more than 30% of commercially available drugs are metabolized by CYP3A4. In this study, we examined the effects of cholesterol and cholic acid on the expression level and activity of CYP3A4 in hCYP3A mice that have a human CYP3A gene cluster and show human-like regulation of the coding genes. A normal diet (ND, CE-2), CE-2 with 1% cholesterol and 0.5% cholic acid (HCD) or CE-2 with 0.5% cholic acid was given to the mice. The plasma concentrations of cholesterol, cholic acid and its metabolites in HCD mice were higher than those in ND mice. In this condition, the expression levels of hepatic CYP3A4 and the hydroxylation activities of triazolam, a typical CYP3A4 substrate, in liver microsomes of HCD mice were higher than those in liver microsomes of ND mice. Furthermore, plasma concentrations of triazolam in HCD mice were lower than those in ND mice. In conclusion, our study suggested that hepatic CYP3A4 expression and activity are influenced by the combination of cholesterol and cholic acid in vivo.


Assuntos
Colesterol , Ácido Cólico , Citocromo P-450 CYP3A , Fígado , Microssomos Hepáticos , Triazolam , Ácido Cólico/metabolismo , Animais , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , Microssomos Hepáticos/metabolismo , Colesterol/metabolismo , Colesterol/sangue , Camundongos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Masculino , Triazolam/farmacocinética , Triazolam/metabolismo , Humanos , Camundongos Transgênicos , Hidroxilação
15.
Front Cell Neurosci ; 18: 1347535, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650656

RESUMO

Astrocytes represent the most abundant cell type in the brain, where they play critical roles in synaptic transmission, cognition, and behavior. Recent discoveries show astrocytes are involved in synaptic dysfunction during Alzheimer's disease (AD). AD patients have imbalanced cholesterol metabolism, demonstrated by high levels of side-chain oxidized cholesterol known as 27-hydroxycholesterol (27-OH). Evidence from our laboratory has shown that elevated 27-OH can abolish synaptic connectivity during neuromaturation, but its effect on astrocyte function is currently unclear. Our results suggest that elevated 27-OH decreases the astrocyte function in vivo in Cyp27Tg, a mouse model of brain oxysterol imbalance. Here, we report a downregulation of glutamate transporters in the hippocampus of CYP27Tg mice together with increased GFAP. GLT-1 downregulation was also observed when WT mice were fed with high-cholesterol diets. To study the relationship between astrocytes and neurons, we have developed a 3D co-culture system that allows all the cell types from mice embryos to differentiate in vitro. We report that our 3D co-cultures reproduce the effects of 27-OH observed in 2D neurons and in vivo. Moreover, we found novel degenerative effects in astrocytes that do not appear in 2D cultures, together with the downregulation of glutamate transporters GLT-1 and GLAST. We propose that this transporter dysregulation leads to neuronal hyperexcitability and synaptic dysfunction based on the effects of 27-OH on astrocytes. Taken together, these results report a new mechanism linking oxysterol imbalance in the brain and synaptic dysfunction through effects on astrocyte function.

16.
Insects ; 15(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38667417

RESUMO

By-product-based diets have the potential to improve the environmental and economic sustainability of Tenebrio molitor (Linnaeus, 1758) production. However, evaluations of the efficacy of new diets are generally focused on larval performance, while the effect on adults is poorly understood. This aim of this study was to evaluate diets enriched with tomato pomace over a complete breeding cycle. The results showed that when used as an oviposition substrate, all the tested diets, including tomato pomace (T), outperformed the control bran-yeast diet (WY, 95:5 ratio), possibly due to the presence of cholesterol and linoleic acid. The adults fed with the bran-tomato pomace-brewer's spent grain diet (WTB, 50:27:23 ratio), the bran-tomato pomace-yeast diet (WTY, 50:41:9 ratio), and the bran-tomato pomace diet (WT, 50:50 ratio) produced significantly more larvae than those fed with the WY diet. The WTB diet (despite being yeast-free) performed similarly to the WY control diet during the subsequent larval growth phase, making it suitable for the entire production cycle. In conclusion, the results show that tomato pomace can be used a valid by-product in the formulation of efficient diets for the breeding of T. molitor and also provide an alternative to expensive yeast.

17.
Healthcare (Basel) ; 12(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38667581

RESUMO

BACKGROUND: Betaine, an osmolyte derivative of the metabolite choline and the amino acid glycine, acts as a methyl donor in the conversion of homocysteine to methionine and is involved in the maintenance of adequate lipid metabolism. There is growing evidence for the role of betaine in the development of various lipid-related diseases, including dyslipidemia and cardiovascular risk. This study aimed to analyze associations between betaine intake and blood lipid profiles in Mexican subjects. METHODS: A total of 212 adults were randomly recruited in the city of Tijuana, Baja California, Mexico. Betaine intake was estimated using Nutritionist Pro software. Body composition and metabolic measurements were obtained by conventional methods. In the total sample, the average intake of betaine was 14.32 mg/d. Individuals were categorized into three groups according to tertiles of betaine consumption: tertile/group 1 (<4.16 mg/d), tertile/group 2 (4.16-12.02 mg/d), and tertile/group 3 (>12.02 mg/d). RESULTS: Compared to group 3, subjects within group 1 had higher serum levels of total cholesterol (p = 0.001), LDL-c (p = 0.026), and non-HDL-c (p = 0.021). In addition, significant negative Pearson correlations were found between betaine intake and the serum levels of total cholesterol (r = -0.432, 95% CI, -0.684, -0.185, p = 0.001), LDL-c (r = -0.370, 95% CI, -0.606, -0.134, p = 0.002), and non-HDL-c (r = -0.351, 95%CI, -0.604, -0.098, p = 0.007). CONCLUSIONS: Our results show that a low intake of betaine is associated with elevated blood cholesterol levels in Mexican subjects. On this basis, betaine consumption could be used as an additional dietary measure for cardiovascular care. However, additional studies are required to confirm our results in other Mexican regions as well as in other populations worldwide.

18.
J Cardiovasc Dev Dis ; 11(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38667738

RESUMO

BACKGROUND AND AIM: There are few prospective data on the prognostic value of normal admission low-density lipoprotein cholesterol (LDL-C) in statin-naïve patients with acute coronary syndromes (ACS) who are treated with a preemptive invasive strategy. We aimed to analyze the proportion of patients with normal LDL-C at admission for ACS in our practice, and their characteristics and clinical outcomes in comparison to patients with high admission LDL-C. PATIENTS AND METHODS: Two institutions' prospective registries of patients with confirmed ACS from Jan 2017 to Jan 2023 were used to identify 1579 statin-naïve patients with no history of prior coronary artery disease (CAD), and with available LDL-C admission results, relevant clinical and procedural data, and short- and long-term follow-up data. Normal LDL-C at admission was defined as lower than 2.6 mmol/L. All demographic, clinical, procedural, and follow-up data were compared between patients with normal LDL-C and patients with a high LDL-C level (≥2.6 mmol/L) at admission. RESULTS: There were 242 (15%) patients with normal LDL-C at admission. In comparison to patients with high LDL-cholesterol at admission, they were significantly older (median 67 vs. 62 years) with worse renal function, had significantly more cases of diabetes mellitus (DM) (26% vs. 17%), peripheral artery disease (PAD) (14% vs. 9%), chronic obstructive pulmonary disease (COPD) (8% vs. 2%), and psychological disorders requiring medical attention (19% vs. 10%). There were no significant differences in clinical type of ACS. Complexity of CAD estimated by coronary angiography was similar between the two groups (median Syntax score 12 for both groups). There were no significant differences in rates of complete revascularization (67% vs. 72%). Patients with normal LDL-C had significantly lower left ventricular ejection fraction (LVEF) at discharge (median LVEF 52% vs. 55%). Patients with normal LDL-C at admission had both significantly higher in-hospital mortality (5% vs. 2%, RR 2.07, 95% CI 1.08-3.96) and overall mortality during a median follow-up of 43 months (27% vs. 14%, RR 1.86, 95% CI 1.45-2.37). After adjusting for age, renal function, presence of diabetes mellitus, PAD, COPD, psychological disorders, BMI, and LVEF at discharge in a multivariate Cox regression analysis, normal LDL-C at admission remained significantly and independently associated with higher long-term mortality during follow-up (RR 1.48, 95% CI 1.05-2.09). CONCLUSIONS: A spontaneously normal LDL-C level at admission for ACS in statin-naïve patients was not rare and it was an independent risk factor for both substantially higher in-hospital mortality and mortality during long-term follow-up. Patients with normal LDL-C and otherwise high total cardiovascular risk scores should be detected early and treated with optimal medical therapy. However, additional research is needed to reveal all the missing pieces in their survival puzzle after ACS-beyond coronary anatomy, PCI optimization, numerical LDL-C levels, and statin therapy.

19.
Membranes (Basel) ; 14(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38668107

RESUMO

Giant unilamellar vesicles (GUVs) are membrane models used to study membrane properties. Electroformation is one of the methods used to produce GUVs. During electroformation protocol, dry lipid film is formed. The drying of the lipid film induces the cholesterol (Chol) demixing artifact, in which Chol forms anhydrous crystals which do not participate in the formation of vesicles. This leads to a lower Chol concentration in the vesicle bilayers compared to the Chol concentration in the initial lipid solution. To address this problem, we propose a novel electroformation protocol that includes rapid solvent exchange (RSE), plasma cleaning, and spin-coating methods to produce GUVs. We tested the protocol, focusing on vesicles with a high Chol content using different spin-coating durations and vesicle type deposition. Additionally, we compared the novel protocol using completely dry lipid film. The optimal spin-coating duration for vesicles created from the phosphatidylcholine/Chol mixture was 30 s. Multilamellar vesicles (MLVs), large unilamellar vesicles (LUVs) obtained by the extrusion of MLVs through 100 nm membrane pores and LUVs obtained by extrusion of previously obtained LUVs through 50 nm membrane pores, were deposited on an electrode for 1.5/1 Chol/phosphatidylcholine (POPC) lipid mixture, and the results were compared. Electroformation using all three deposited vesicle types resulted in a high GUV yield, but the deposition of LUVs obtained by the extrusion of MLVs through 100 nm membrane pores provided the most reproducible results. Using the deposition of these LUVs, we produced high yield GUVs for six different Chol concentrations (from 0% to 71.4%). Using a protocol that included dry lipid film GUVs resulted in lower yields and induced the Chol demixing artifact, proving that the lipid film should never be subjected to drying when the Chol content is high.

20.
J Mol Neurosci ; 74(2): 49, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668787

RESUMO

The pathogenesis of Alzheimer's disease (AD) is complex and involves an imbalance between production and clearance of amyloid-ß peptides (Aß), resulting in accumulation of Aß in senile plaques. Hypercholesterolemia is a major risk factor for developing AD, with cholesterol shown to accumulate in senile plaques and increase production of Aß. ABCG4 is a member of the ATP-binding cassette transporters predominantly expressed in the CNS and has been suggested to play a role in cholesterol and Aß efflux from the brain. In this study, we bred Abcg4 knockout (KO) with the APPSwe,Ind (J9) mouse model of AD to test the hypothesis that loss of Abcg4 would exacerbate the AD phenotype. Unexpectedly, no differences were observed in novel object recognition (NOR) and novel object placement (NOP) behavioral tests, or on histologic examinations of brain tissues for senile plaque numbers. Furthermore, clearance of radiolabeled Aß from the brains did not differ between Abcg4 KO and control mice. Metabolic testing by indirect calorimetry, glucose tolerance test (GTT), and insulin tolerance test (ITT) were also mostly similar between groups with only a few mild metabolic differences noted. Overall, these data suggest that the loss of ABCG4 did not exacerbate the AD phenotype.


Assuntos
Subfamília G de Transportadores de Cassetes de Ligação de ATP , Doença de Alzheimer , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Camundongos , Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Masculino , Encéfalo/metabolismo , Encéfalo/patologia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/genética , Camundongos Endogâmicos C57BL , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Placa Amiloide/genética
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