Organosulfur Compounds, S-Allyl-L-Cysteine and S-Ethyl-L-Cysteine, Target PCSK-9/LDL-R-Axis to Ameliorate Cardiovascular, Hepatic, and Metabolic Changes in High Carbohydrate and High Fat Diet-Induced Metabolic Syndrome in Rats.

Metabolic syndrome (MetS) is an ever-evolving set of diseases that poses a serious health risk in many countries worldwide. Existing evidence illustrates that individuals with MetS have a 30%-40% higher chance of acquiring type 2 diabetes mellitus (T2DM), cardiovascular disease (CVD), or both. This study was undertaken to uncover the regulatory role of natural organosulfur compounds (OSCs), S-allyl-L-cysteine (SAC), and S-ethyl-L-cysteine (SEC), in targeting high carbohydrate high fat (HCHF)-diet-induced MetS-associated risk management. Our findings suggested that SAC and SEC ameliorated HCHF-diet-induced diabetic profiles, plasma lipid and lipoprotein level, liver function, oxidative-stress, inflammatory cytokines, and chemokines including monocyte chemoattractant protein-1 (MCP-1), lipid peroxidation, plasma proprotein convertase subtilisin/kexin type-9 (PCSK-9), and high-sensitivity C-reactive protein (hs-CRP). Moreover, the assessment of the hepatic mRNA expression of the key genes involved in cholesterol homeostasis depicted that SAC and SEC downregulated the PCSK-9 mRNA expression via targeting the expression of HNF-1α, a transcriptional activator of PCSK-9. On the other hand, the LDL-receptor (LDL-R) expression was upregulated through the activation of its transcriptional regulator sterol regulatory element binding protein-2 (SREBP-2). In addition, the activity and the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme-A reductases (HMG-R) and peroxisome proliferator-activated receptors (PPARs) were also improved by the treatment of SAC and SEC. We concluded that SAC and SEC can protect against MetS via improving the lipid and lipoprotein content, glycemic indices, hepatic function, targeting the inflammatory cascades, and oxidative imbalance, regulation of the mRNA expression of PCSK-9, LDL-R, SREBP-2, HNF-1α, PPARs, and inflammatory biomarkers.

Therapeutic Gene Editing in Dyslipidemias.

Dyslipidemia, characterized by abnormal lipid levels in the blood, significantly escalates the risk of atherosclerotic cardiovascular disease and requires effective treatment strategies. While existing therapies can be effective, long-term adherence is often challenging. There has been an interest in developing enduring and more efficient solutions. In this context, gene editing, particularly clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) technology, emerges as a groundbreaking approach, offering potential long-term control of dyslipidemia by directly modifying gene expression. This review delves into the mechanistic insights of various gene-editing tools. We comprehensively analyze various pre-clinical and clinical studies, evaluating the safety, efficacy, and therapeutic implications of gene editing in dyslipidemia management. Key genetic targets, such as low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), angiopoietin-like protein 3 (ANGPTL3), apolipoprotein C3 (APOC3), and lipoprotein (a) (Lp(a)), known for their pivotal roles in lipid metabolism, are scrutinized. The paper highlights the promising outcomes of gene editing in achieving sustained lipid homeostasis, discusses the challenges and ethical considerations in genome editing, and envisions the future of gene therapy in revolutionizing dyslipidemia treatment and cardiovascular risk reduction.

Cholesterol dynamics in rabbit liver: High-fat diet, olive oil, and synergistic dietary effects.

BACKGROUND & AIMS: Lipid metabolism disorders contribute to a range of human diseases, including liver-related pathologies. Rabbits, highly sensitive to dietary cholesterol, provide a model for understanding the development of liver disorders. Sterol regulatory element-binding protein isoform 2 (SREBP2) crucially regulates intracellular cholesterol pathways. Extra-virgin olive oil (EVOO) has shown reducing cholesterol levels and restoring liver parameters affected by HFD. The aim was to investigate the molecular impact of an HFD and supplemented with EVOO on rabbit liver cholesterol metabolism. APPROACH & RESULTS: Male rabbits were assigned to dietary cohorts, including control, acute/chronic HFD, sequential HFD with EVOO, and EVOO. Parameters such as serum lipid profiles, hepatic enzymes, body weight, and molecular analyses. After 6 months of HFD, plasma and hepatic cholesterol increased with decreased SREBP2 and 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) expression. Prolonged HFD increased cholesterol levels, upregulating SREBP2 mRNA and HMGCR protein. Combining this with EVOO lowered cholesterol, increased SREBP2 mRNA, and upregulated low-density lipoprotein receptor (LDLR) expression. HFD-induced metabolic dysfunction-associated fatty liver disease was mitigated by EVOO. In conclusion, the SREBP2 system responds to dietary changes. CONCLUSIONS: In rabbits, the SREBP2 system responds to dietary changes. Acute HFD hinders cholesterol synthesis, while prolonged HFD disrupts regulation, causing SREBP2 upregulation. EVOO intake prompts LDLR upregulation, potentially enhancing cholesterol clearance and restoring hepatic alterations.

IL-6R (trans-signaling) is a key regulator of reverse cholesterol transport in lipid-laden macrophages.

Atherosclerosis is a cardiovascular disease caused by cholesterol-laden arterial plaques. This study evaluated the correlation between interleukin-6 (IL-6), its receptors (IL6R/CD126), and glycoprotein 130 (gp130) alongside atherosclerosis biomarkers in a cohort of 142 subjects, equally divided between lean and obese individuals. Subsequent analyses used THP-1-derived macrophages to assess the biochemical impact of inhibiting IL-6 receptors. IL-6 secretion increased with atherosclerosis in obese subjects, while IL6R/CD126 and gp130 on monocytes decreased. Pharmacological gp130 inhibition altered lipid metabolism, increasing LDLR gene expression and cholesterol synthesis via SREBF2 and mevalonate kinase, along with HMG-CoA reductase at protein levels. gp130-deficient cells produced more cholesterol and had lower ABCA1 levels, suggesting hindered cholesterol efflux. Filipin III staining confirmed cholesterol retention in gp130-inhibited cells. Ex-vivo investigation on lean PBMCs further defined the impact of gp130 inhibition on the reduction of cholesterol efflux. Our results indicates gp130 is crucial for macrophage reverse cholesterol transport and may be a target for atherosclerosis treatments.

The role of proprotein convertase subtilisin/kexin 9 (PCSK9) in macrophage activation: a focus on its LDL receptor-independent mechanisms.

Recent clinical trials demonstrated that proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors reduce cardiovascular events without affecting systemic inflammation in the patients with coronary artery disease, as determined by high sensitivity C-reactive protein (CRP) levels. However, its pro-inflammatory effects in cardiovascular disease in humans and experimental animals beyond the traditional cholesterol receptor-dependent lipid metabolism have also called attention of the scientific community. PCSK9 may target receptors associated with inflammation other than the low-density lipoprotein receptor (LDLR) and members of the LDLR family. Accumulating evidence suggests that PCSK9 promotes macrophage activation not only via lipid-dependent mechanisms, but also lipid-independent and LDLR-dependent or -independent mechanisms. In addition to dyslipidemia, PCSK9 may thus be a potential therapeutic target for various pro-inflammatory diseases.

Inhibition of PCSK9 enhances the anti-hepatocellular carcinoma effects of TCR-T cells and anti-PD-1 immunotherapy.

T cells play important roles in antitumor immunity. However, given that the hepatocellular carcinoma (HCC) tumor microenvironment confers resistance to T cell-based immunotherapies, novel strategies to boost T cell-mediated antitumor efficacy are urgently needed for the treatment of HCC. Here, we show that high proprotein convertase subtilisin/kexin type9 (PCSK9) expression was negatively associated with HCC patient's overall survival and markers of CD8+ T cells. Pharmacological inhibition of PCSK9 enhanced tumor-specific killing and downregulated PD-1 expression of AFP-specific TCR-T. Inhibition of PCSK9 significantly enhances the anti-HCC efficacy of TCR-T cells and anti-PD-1 immunotherapy in vivo. Moreover, PCSK9 inhibitor suppressed HCC growth dependent on CD8+ T cells. Mechanically, pharmacological inhibition of PCSK9 promoted low-density lipoprotein receptor (LDLR)-mediated activation of mTORC1 signaling in CD8+ T cells. LDLR deficiency was shown to impair cellular mTORC1 signaling and the anti-HCC function of CD8 T cells. On the basis of our findings in this study, we propose a potential metabolic intervention strategy that could be used to enhance the antitumor effects of immunotherapy for HCC.

Cellular and functional evaluation of LDLR missense variants reported in hypercholesterolemic patients demonstrates their hypomorphic impacts on trafficking and LDL internalization.

Background: Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by increased LDL-cholesterol levels. About 85% of FH cases are caused by LDLR mutations encoding the low-density lipoprotein receptor (LDLR). LDLR is synthesized in the endoplasmic reticulum (ER) where it undergoes post-translational modifications and then transported through Golgi apparatus to the plasma membrane. Over 2900 LDLR variants have been reported in FH patients with limited information on the pathogenicity and functionality of many of them. This study aims to elucidate the cellular trafficking and functional implications of LDLR missense variants identified in suspected FH patients using biochemical and functional methods. Methods: We used HeLa, HEK293T, and LDLR-deficient-CHO-ldlA7 cells to evaluate the subcellular localization and LDL internalization of ten LDLR missense variants (p.C167F, p.D178N, p.C243Y, p.E277K, p.G314R, p.H327Y, p.D477N, p.D622G, p.R744Q, and p.R814Q) reported in multiethnic suspected FH patients. We also analyzed the functional impact of three variants (p.D445E, p.D482H, and p.C677F), two of which previously shown to be retained in the ER. Results: We show that p.D622G, p.D482H, and p.C667F are largely retained in the ER whereas p.R744Q is partially retained. The other variants were predominantly localized to the plasma membrane. LDL internalization assays in CHO-ldlA7 cells indicate that p.D482H, p.C243Y, p.D622G, and p.C667F have quantitatively lost their ability to internalize Dil-LDL with the others (p.C167F, p.D178N, p.G314R, p.H327Y, p.D445E, p.D477N, p.R744Q and p.R814Q) showing significant losses except for p.E277K which retained full activity. However, the LDL internalization assay is only to able evaluate the impact of the variants on LDL internalization and not the exact functional defects such as failure to bind LDL. The data represented illustrate the hypomorphism nature of variants causing FH which may explain some of the variable expressivity of FH. Conclusion: Our combinatorial approach of in silico, cellular, and functional analysis is a powerful strategy to determine pathogenicity and FH disease mechanisms which may provide opportunitites for novel therapeutic strategies.

Identification of regulatory networks and crosstalk factors in brown adipose tissue and liver of a cold-exposed cardiometabolic mouse model.

BACKGROUND: Activation of brown adipose tissue (BAT) has gained attention due to its ability to dissipate energy and counteract cardiometabolic diseases (CMDs). METHODS: This study investigated the consequences of cold exposure on the BAT and liver proteomes of an established CMD mouse model based on LDL receptor-deficient (LdlrKO) mice fed a high-fat, high-sucrose, high-cholesterol diet for 16 weeks. We analyzed energy metabolism in vivo and performed untargeted proteomics on BAT and liver of LdlrKO mice maintained at 22 °C or 5 °C for 7 days. RESULTS: We identified several dysregulated pathways, miRNAs, and transcription factors in BAT and liver of cold-exposed Ldlrko mice that have not been previously described in this context. Networks of regulatory interactions based on shared downstream targets and analysis of ligand-receptor pairs identified fibrinogen alpha chain (FGA) and fibronectin 1 (FN1) as potential crosstalk factors between BAT and liver in response to cold exposure. Importantly, genetic variations in the genes encoding FGA and FN1 have been associated with cardiometabolic-related phenotypes and traits in humans. DISCUSSION: This study describes the key factors, pathways, and regulatory networks involved in the crosstalk between BAT and the liver in a cold-exposed CMD mouse model. These findings may provide a basis for future studies aimed at testing whether molecular mediators, as well as regulatory and signaling mechanisms involved in tissue adaption upon cold exposure, could represent a target in cardiometabolic disorders.

E3 ubiquitin ligase MARCH1 reduces inflammation and pyroptosis in cerebral ischemia-reperfusion injury via PCSK9 downregulation.

Pyroptosis has been regarded as caspase-1-mediated monocyte death that induces inflammation, showing a critical and detrimental role in the development of cerebral ischemia-reperfusion injury (IRI). MARCH1 is an E3 ubiquitin ligase that exerts potential anti-inflammatory functions. Therefore, the study probed into the significance of MARCH1 in inflammation and pyroptosis elicited by cerebral IRI. Middle cerebral artery occlusion/reperfusion (MCAO/R)-treated mice and oxygen glucose deprivation/reoxygenation (OGD/R)-treated hippocampal neurons were established to simulate cerebral IRI in vivo and in vitro. MARCH1 and PCSK9 expression was tested in MCAO/R-operated mice, and their interaction was identified by means of the cycloheximide assay and co-immunoprecipitation. The functional roles of MARCH1 and PCSK9 in cerebral IRI were subsequently determined by examining the neurological function, brain tissue changes, neuronal viability, inflammation, and pyroptosis through ectopic expression and knockdown experiments. PCSK9 expression was increased in the brain tissues of MCAO/R mice, while PCSK9 knockdown reduced brain damage and neurological deficits. Additionally, inflammation and pyroptosis were inhibited in OGD/R-exposed hippocampal neurons upon PCSK9 knockdown, accompanied by LDLR upregulation and NLRP3 inflammasome inactivation. Mechanistic experiments revealed that MARCH1 mediated ubiquitination and degradation of PCSK9, lowering PCSK9 protein expression. Furthermore, it was demonstrated that MARCH1 suppressed inflammation and pyroptosis after cerebral IRI by downregulating PCSK9 both in vivo and in vitro. Taken together, the present study demonstrate the protective effect of MARCH1 against cerebral IRI through PCSK9 downregulation, which might contribute to the discovery of new therapies for improving cerebral IRI.

AGXT2 Suppresses the Proliferation and Dissemination of Hepatocellular Carcinoma Cells by Modulating Intracellular Lipid Metabolism.

Purpose: Alanine glyoxylate aminotransferase (AGXT) family members are crucial in cancer processes, but their role in hepatocellular carcinoma (HCC) metabolism is unclear. This study investigates AGXT2's function in HCC. Patients and Methods: AGTX2 expression was studied using bioinformatics, real-time reverse transcriptase-polymerase chain reaction (RT-qPCR), Western blot, and Enzyme-linked immunosorbent assay (ELISA). A lentivirus-induced AGTX2 overexpression cell model was analyzed with RNA sequencing (RNA-seq) and liquid chromatography-mass spectrometry (LC-MS). Cholesterol levels were confirmed by Oil Red O staining. AGTX2 effects were evaluated through cell cycle analysis, wound healing, and transwell migration assays.Tumorigenic effects were observed in NOD-SCID IL2Rγnull (NTG) mice in subcutaneous experiments. Protein interaction was examined through co-immunoprecipitation methods. Results: We observed a significant reduction in AGXT2 mRNA and protein levels in both HCC tumor tissues and serum samples from patients with liver cancer, which was associated with a worse prognosis. The activation of AGXT2 has been shown to effectively decrease cholesterol levels in liver cancer cells, serving as an antagonist in the cholesterol metabolism pathway. An increase in low density lipoprotein receptor (LDLR) mRNA was noted in cells overexpressing AGXT2, accompanied by a decrease in LDLR protein and an elevation in proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and protein levels. Molecular docking and co-immunoprecipitation experiments further elucidated the interaction between AGXT2 and LDLR proteins. AGXT2 was observed to suppress the migratory and invasive capabilities of HCC cells, inducing cell cycle arrest in the G2/M phase. AGXT2 activation inhibited subcutaneous liver cancer tumor growth in NTG mice. Conclusion: AGXT2 was found to lower cholesterol levels in liver cancer cells, possibly through interactions with the LDLR protein and modulation of PCSK9-mediated LDLR degradation. This mechanism may impede cholesterol transport to liver cancer cells, thereby suppressing their growth and metastasis.

Microglia are not necessary for maintenance of blood-brain barrier properties in health, but PLX5622 alters brain endothelial cholesterol metabolism.

Microglia, the resident immune cells of the central nervous system, are intimately involved in the brain's most basic processes, from pruning neural synapses during development to preventing excessive neuronal activity throughout life. Studies have reported both helpful and harmful roles for microglia at the blood-brain barrier (BBB) in the context of disease. However, less is known about microglia-endothelial cell interactions in the healthy brain. To investigate the role of microglia at a healthy BBB, we used the colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX5622 to deplete microglia and analyzed the BBB ultrastructure, permeability, and transcriptome. Interestingly, we found that, despite their direct contact with endothelial cells, microglia are not necessary for the maintenance of BBB structure, function, or gene expression in the healthy brain. However, we found that PLX5622 treatment alters brain endothelial cholesterol metabolism. This effect was independent from microglial depletion, suggesting that PLX5622 has off-target effects on brain vasculature.

LDLR variant classification for improved cardiovascular risk prediction in familial hypercholesterolemia.

BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is a genetic disorder marked by high LDL cholesterol and an increased premature coronary artery disease (CAD) risk. Current dichotomous classification of LDL receptor gene (LDLR) variants may inadequately capture patient variability in LDL cholesterol levels and CAD risk. This study assessed a novel approach for determining LDLR variant severity using variant-specific LDL cholesterol percentiles. METHODS: Participants of the Dutch FH cascade screening program were screened for 456 LDLR variants. For each LDLR variant carrier, a sex- and age-specific LDL cholesterol percentile was derived from the LDL cholesterol level measured at study entry, i.e. generally from the blood drawn for DNA analysis. These percentiles were used to calculate the mean LDL cholesterol percentile for each variant. Based on the variant-specific LDL cholesterol percentiles, carriers were grouped into the following LDL cholesterol strata: <75th, 75th-88th, 88th-92nd, 92nd-96.5th, 96.5th-98th, and ≥98th percentile. Additionally, variants were categorized into class 1 (LDLR deficient) and non-class 1 (often LDLR defective) variants. CAD risk between carriers in the different LDL cholesterol strata and non-carriers was compared using a Cox proportional hazard model. RESULTS: Out of 35,067 participants, 12,485 (36 %) LDLR variant carriers (mean age 38.0 ± 20.0 years, 47.7 % male) were identified. Carriers had a 5-fold higher CAD risk compared with non-carriers. Hazard ratios for CAD increased gradually from 2.2 (95%CI 0.97-5.0) to 12.0 (95%CI 5.5-24.8) across the LDL cholesterol strata. A 7.3-fold and 3.9-fold increased CAD risk was observed in carriers of class 1 and non-class 1 LDLR variants, respectively. CONCLUSIONS: This study presents a refined approach for classifying LDLR variants based on their impact on LDL cholesterol levels, allowing for more precise, genotype-specific CAD risk estimation in FH patients compared with traditional methods.

Bioactive alkaloids from Nepalese Corydalis chaerophylla D.C. acting on the regulation of PCSK9 and LDL-R in vitro.

Four new alkaloids Chaeronepaline-A (1), Chaeronepaline-B (2), Chaeronepaline-C (3), and Chaeronepaline-D (4) were isolated from Corydalis chaerophylla D.C. collected from Nepal and their structures were elucidated by spectroscopic data, 1D, 2D NMR and mass spectrometry. The structures were established as 3,12- Dimethoxy-5,6-dihydroisoquinolino [2,1-b] isoquinolin- 7- ium- 2, 9- diol (1), 7-methyl-5, 6, 7, 8-tetrahydroisoquinoline- 2, 3- methylenedioxy- (8-> 9)- 10, 12- methylenedioxy- benzoic-16-acid (2), 7- methyl-5, 6, 7, 8- tetrahydro- 8H-spiro-9,14-dihydroxy-11,12-methylenedioxy-indane-isoquinoline (3) and 7- methyl-5, 6, 7, 8- tetrahydro- 8H-spiro-9,14-dihydroxy-11,12-methylenedioxy-indane-isoquinoline-N-oxide (4). The new alkaloids were tested in human hepatoma cell line to assess their ability to modulate the expression of low-density lipoprotein receptor (LDL-R), of proprotein convertase subtilisin/kexin 9 (PCSK9) and to affect cellular cholesterol biosynthesis with the aim to evaluate their potential hypocholesterolemic effect. Results indicated that compounds 2 and 3 upregulate the LDLR, and inhibited the cholesterol biosynthesis with compound 2, which also reduced the secretion of PCSK9 by Huh7 cells. These in vitro data indicated a potential hypocholesterolemic effect of compound 2 that requires further in vivo validation.

Chemical constituents from the roots of Cynanchum wilfordii with PCSK9 secretion inhibitory activities.

From the Cynanchum wilfordii roots, 32 compounds, including 5 previously undescribed (1, 4-6, 12) and 27 known (2, 3, 7-11, 13-32) compounds, were isolated, and their structures were elucidated using NMR spectroscopic data and MS data aided by ECD calculations or the modified Mosher's reaction. All isolates were tested for their inhibitory effects on proprotein convertase subtilisin/kexin type 9 (PCSK9) secretion. Among the isolates, compound 4, a methyl cholesterol analog, exhibited the most potent effect in reducing PCSK9 secretion, along with PCSK9 downregulation at the mRNA and protein levels via FOXO1/3 upregulation. Moreover, compound 4 attenuated statin-induced PCSK9 expression and enhanced the uptake of DiI-LDL low-density lipoprotein. Thus, compound 4 is suggested to be a potential candidate for controlling cholesterol levels.

A Japanese Case of Familial Hypercholesterolemia with a Protein-truncating Variant in LDLR and a PCSK9 Variant without Significant Atherosclerosis but Showing Remarkable Achilles Tendon Thickening.

The patient was a 54-year-old woman with familial hypercholesterolemia and remarkable Achilles tendon thickening. At 20 years old, the patient had a total cholesterol level of approximately 300 mg/dL. She started receiving rosuvastatin (5 mg/day) for low-density lipoprotein cholesterol (LDL-C) 235 mg/dL at 42 years old, which was increased to 10 mg/day at 54 years old, decreasing her serum LDL-C level to approximately 90 mg/dL. The serum Lp (a) level was 9 mg/dL. A computed tomography coronary angiogram showed no significant stenosis. Next-generation sequencing revealed a frameshift variant in LDL receptor (LDLR) (heterozygous) and a missense variant in proprotein convertase subtilisin/kaxin type 9 (PCSK9) (heterozygous). Continued statin therapy, in addition to low Lp (a) and female sex, can help prevent cardiovascular disease.

Biparatopic anti-PCSK9 antibody enhances the LDL-uptake in HepG2 cells.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has emerged as a promising therapeutic target to reduce lipids. In 2020, we reported a chimeric camelid-human heavy chain antibody VHH-B11-Fc targeting PCSK9. Recently, it was verified that VHH-B11 binds one linear epitope in the PCSK9 hinge region. To enhance its druggability, we have developed a novel biparatopic B11-H2-Fc Ab herein. Thereinto, surface plasmon resonance (SPR) confirmed the epitope differences in binding-PCSK9 among VHH-B11, VHH-H2 and the approved Repatha. Additionally, SPR revealed the B11-H2-Fc exhibits an avidity of approximately 0.036 nM for PCSK9, representing a considerable increase compared to VHH-B11-Fc (~ 0.69 nM). Moreover, we found the Repatha and B11-H2-Fc exhibited > 95% PCSK9 inhibition efficiency compared to approximately 48% for the VHH-Fc at 7.4 nM (P < 0.0005). Further, we verified its biological activity using the human hepatoma cells G2 model, where the B11-H2-Fc exhibited almost 100% efficiency in PCSK9 inhibition at only 0.75 µM. The immunoblotting results of low-density lipoprotein cholesterol (LDL-c) uptake assay also demonstrated the excellent performance of B11-H2-Fc on recovering the LDL-c receptor (LDLR), as strong as the Repatha (P > 0.05). These findings provide the first evidence of the efficacy of a novel Ab targeting PCSK9 in the field of lipid-lowering drugs.

Bile acids promote lipopolysaccharide clearance via the hepato-biliary pathway in broiler chickens.

Lipopolysaccharide (LPS) acts as a trigger that disrupts metabolic functions and the immune system. While bile acids (BA) have detoxification and anti-inflammatory effects, their role in promoting LPS excretion in broiler chickens remains unclear. This study aimed to investigate the potential of exogenous BA to enhance hepatic clearance of LPS and thereby potentially alleviate LPS-induced liver injury in broiler chickens. Forty-five 21-day-old male broiler chickens were randomly assigned to three groups: the control group, which received daily intraperitoneal injections of a solvent for LPS treatment and a gavage solvent for BA treatment; the LPS group, which received daily intraperitoneal injections of 0.5 mg/kg body weight LPS and a gavage solvent for BA treatment; the LPS + BA group, which received daily intraperitoneal injections of 0.5 mg/kg body weight LPS and 60 mg/kg body weight BA by gavage. BA administered by gavage protected the broiler chickens from increases in liver and spleen indices, systemic inflammatory response, and hepatic damage induced by LPS. Hepatic clearance of LPS was enhanced, as evidenced by decreased serum LPS levels and accelerated excretion into the gallbladder. Additionally, the LPS-induced downregulation of detoxification genes, including those for the lipoprotein receptor and bile acids export pump, was reversed by BA administered by gavage. Furthermore, nuclear transcription factors such as the Farnesoid X receptor (FXR) and Liver X receptor α (LXRα) were enhanced in BA-treated broiler chickens. These findings suggest that BA administration via gavage enhances hepatic LPS clearance through the upregulation of hepatic uptake and efflux proteins, likely mediated by the activation of nuclear transcription factors FXR and LXRα.

Advances in nucleic acid-targeted therapies for cardiovascular disease prevention.

Nucleic acid-based therapies are being rapidly developed for prevention and management of cardiovascular diseases (CVD). Remarkable advancements have been achieved in the delivery, safety, and effectiveness of these therapeutics in the past decade. These therapies can also modulate therapeutic targets that cannot be sufficiently addressed using traditional drugs or antibodies. Among the nucleic acid-targeted therapeutics under development for CVD prevention are RNA-targeted approaches, including antisense oligonucleotides (ASO), small interfering RNAs (siRNA), and novel genome editing techniques. Genetic studies have identified potential therapeutic targets that are suggested to play a causative role in development and progression of CVD. RNA- and DNA-targeted therapeutics can be particularly well delivered to the liver, where atherogenic lipoproteins and angiotensinogen (AGT) are produced. Current targets in lipid metabolism include proprotein convertase subtilisin/kexin type 9 (PCSK9), apolipoprotein A (ApoA), apolipoprotein C3 (ApoC3), angiopoietin-like 3 (ANGPTL3). Several large-scale clinical development programs for nucleic acid-targeted therapies in cardiovascular prevention are under way, which may also be attractive from a therapy adherence point of view, given the long action of these therapeutics. In addition to genome editing, the concept of gene transfer is presently under assessment in preclinical and clinical investigations as a potential approach for addressing low-density lipoprotein receptor deficiency. Furthermore, ongoing research is exploring the use of RNA-targeted therapies to treat arterial hypertension by reducing hepatic angiotensinogen (AGT) production. This review summarizes the rapid translation of siRNA and ASO therapeutics as well as gene editing into clinical studies to treat dyslipidemia and arterial hypertension for CVD prevention. It also outlines potential innovative therapeutic options that are likely relevant to the future of cardiovascular medicine.

Comprehensive Analysis of the Prognostic Marker and Immune Infiltrates of LDLR-Related Proteins Family Members in Breast Cancer.

Background & Objective: Breast cancer (BC) is one of the most frequent tumors worldwide, accounting for 15% of all cancer-related deaths. A timely diagnosis of BC is essential for optimal treatment and increasing patients' survival rates. LRP family proteins are important components of cell-surface receptors involved in numerous biological activities. Expression of LRP is related to breast malignancy. In this study, we initially studied the expression of LRPs in BC tissues compared to normal tissues-the relation of LRP expression with relapse-free survival (RFS) and overall survival (OS). Then, we investigated the association of LRPs relation and immune infiltrating abundance. Methods: We analyzed the LDLR family expression and prognostic value in BC by mining UALCAN, TIMER, and Kaplan-Meier plotter databases. Subsequently, we explored the association of LDLR expression and immune infiltrating abundance via the TIMER database. Results: Expression levels of LRP1/2/4/9/10 were found to be higher in the cases with positive estrogen receptors. There was a positive association between LRP1/6 expression and the infiltration of CD8+ T cells, CD4+ T Cell, Macrophage, Dendritic Cell, and Neutrophil. Conclusion: Our study recommends LDLR as a potential prognostic biomarker that can be promising to improve the survival of BC patients' survival. However, further investigations are needed to evaluate the studied LDLR members in more detail.

Development of a PCSK9-targeted nanoparticle vaccine to effectively decrease the hypercholesterolemia.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the low-density lipoprotein receptor (LDLR) and mediates its internalization and degradation, resulting in an increase in LDL cholesterol levels. Recently, PCSK9 emerged as a therapeutic target for hypercholesterolemia and atherosclerosis. In this study, we develop a PCSK9 nanoparticle (NP) vaccine by covalently conjugating the catalytic domain (aa 153-aa 454, D374Y) of PCSK9 to self-assembled 24-mer ferritin NPs. We demonstrate that the PCSK9 NP vaccine effectively induces interfering antibodies against PCSK9 and reduces serum lipids levels in both a high-fat diet-induced hypercholesterolemia model and an adeno-associated virus-hPCSK9D374Y-induced hypercholesterolemia model. Additionally, the vaccine significantly reduces plaque lesion areas in the aorta and macrophages infiltration in an atherosclerosis mouse model. Furthermore, we discover that the vaccine's efficacy relied on T follicular help cells and LDLR. Overall, these findings suggest that the PCSK9 NP vaccine holds promise as an effective treatment for hypercholesterolemia and atherosclerosis.