Hypercholesterolemic Mice Research Articles

Short-Term Western Diet Causes Rapid and Lasting Alterations of Bone Marrow Physiology.

Dietary factors have a significant impact on overall health and western diet (WD) disrupts arterial homeostasis, thereby promoting atherosclerosis. In our study, we investigated the effects of short-term WD on bone marrow vasculature and hematopoiesis in hypercholesterolemic mice. We found that WD rapidly remodels bone marrow arterioles, and these alterations persist even after WD cessation. The proximity between hematopoietic stem cells (HSCs) and arterioles increased with short-term WD, which was associated with a reduced HSC counts as well as an increased number of progenitor cells and a higher production of myeloid cells. Additionally, the remaining HSCs showed increased proliferation, potentially raising susceptibility to clonal hematopoiesis. Collectively, our findings show that short-term WD dramatically alters the bone marrow physiology with lasting consequences.

Resveratrol attenuates efavirenz-induced hepatic steatosis and hypercholesterolemia in mice by inhibiting pregnane X receptor activation and decreasing inflammation

Efavirenz (EFV), a widely prescribed antiviral medication, has been implicated in dyslipidemia and can activate the pregnane X receptor (PXR), leading to hepatic steatosis and hypercholesterolemia in mice. Resveratrol (RES) can ameliorate hepatic steatosis and functions as a partial PXR agonist, capable of mitigating PXR expression induced by other PXR agonists. Therefore, we hypothesized that RES could attenuate EFV-induced hepatic steatosis and hypercholesterolemia by downregulating PXR expression and suppressing inflammatory cytokine production. Here, we conducted an in vivo study involving 6-week-old male mice, which were divided into 4 groups for a 7-day intervention: control (carrier solution), EFV (80 mg/kg), RES (50 mg/kg), and RES + EFV groups. Serum and hepatic tissue samples were collected to assess cholesterol and triglyceride concentrations. Hepatic lipid accumulation was evaluated through hematoxylin-eosin and oil red O staining. Polymerase chain reaction and western blot were performed to quantify hepatic inflammatory factors, lipogenic gene, and PXR expression. Our results indicated that hepatic lipid droplet accumulation was reduced in the RES + EFV group compared with the EFV group. Similarly, the expressions of hepatic inflammatory factors were attenuated in the RES + EFV group relative to the EFV group. Furthermore, RES counteracted the upregulation of hepatic lipid-metabolizing enzymes induced by EFV at both the transcriptional and protein levels. Importantly, PXR expression was downregulated in the RES + EFV group compared with the EFV group. Conclusively, our findings suggest that RES effectively mitigates EFV-induced hepatic steatosis and hypercholesterolemia by inhibiting PXR activation and decreasing inflammation.

Biochemical and cellular (liver and kidney) restorative properties of garlic (Allium sativum) aqueous extract in cow brain-induced hypercholesterolemic model Swiss albino mice

Introduction and aim. Garlic is one of the most popular traditional medicinal herbs which has a number of desirable health benefits. The study was designed to depict the improvement of serum biochemical parameters as well as the histomorphological recovery potential of garlic aqueous extract in hypercholesterolemic mice. Material and methods. A total of thirty Swiss albino mice weighing 24±5g and aged 5 weeks were randomly divided into three groups. Group A: supplied standard mice pellet and water; Group B: standard mice pellet + hypercholesterolemic diet (cow brain: 2 g/kg b.w.t.); and Group C: standard mice pellet + hypercholesterolemic diet (cow brain: 2 g/kg b.w.t.) + garlic extract (25 ml/kg b.w.t.). After four weeks of experimental tenure, samples (blood, liver, and kidney) were collected from each group of mice for serum biochemical analysis and histomorphological study. Results. Compared with hypercholesterolemic mice, total cholesterol (TC), triglyceride (TG) concentration, and low-density lipoprotein (LDL) levels significantly decreased respectively by 7%, 20% and 48% along with high-density lipoprotein (HDL) levels significantly increased by 47% in garlic extract supplemented group. Based on the histological evaluation in the liver sample of group C, both portal and central veins were normal, and fat droplets were not found in the hepatocytes which were found in the liver of group B. On the other hand, unchanged renal cortex, glomerulus, Bowman’s space, and kidney tubules were seen in group C. Conclusion. Therefore, the above findings of the present research would assist to provide affirmation about the cholesterol-decreasing and cellular restoration potentiality of garlic aqueous extract.

Endothelial activation and fibrotic changes are impeded by laminar flow-induced CHK1-SENP2 activity through mechanisms distinct from endothelial-to-mesenchymal cell transition.

The deSUMOylase sentrin-specific isopeptidase 2 (SENP2) plays a crucial role in atheroprotection. However, the phosphorylation of SENP2 at T368 under disturbed flow (D-flow) conditions hinders its nuclear function and promotes endothelial cell (EC) activation. SUMOylation has been implicated in D-flow-induced endothelial-to-mesenchymal transition (endoMT), but the precise role of SENP2 in counteracting this process remains unclear. We developed a phospho-specific SENP2 S344 antibody and generated knock-in (KI) mice with a phospho-site mutation of SENP2 S344A using CRISPR/Cas9 technology. We then investigated the effects of SENP2 S344 phosphorylation under two distinct flow patterns and during hypercholesteremia (HC)-mediated EC activation. Our findings demonstrate that laminar flow (L-flow) induces phosphorylation of SENP2 at S344 through the activation of checkpoint kinase 1 (CHK1), leading to the inhibition of ERK5 and p53 SUMOylation and subsequent suppression of EC activation. We observed a significant increase in lipid-laden lesions in both the aortic arch (under D-flow) and descending aorta (under L-flow) of female hypercholesterolemic SENP2 S344A KI mice. In male hypercholesterolemic SENP2 S344A KI mice, larger lipid-laden lesions were only observed in the aortic arch area, suggesting a weaker HC-mediated atherogenesis in male mice compared to females. Ionizing radiation (IR) reduced CHK1 expression and SENP2 S344 phosphorylation, attenuating the pro-atherosclerotic effects observed in female SENP2 S344A KI mice after bone marrow transplantation (BMT), particularly in L-flow areas. The phospho-site mutation SENP2 S344A upregulates processes associated with EC activation, including inflammation, migration, and proliferation. Additionally, fibrotic changes and up-regulated expression of EC marker genes were observed. Apoptosis was augmented in ECs derived from the lungs of SENP2 S344A KI mice, primarily through the inhibition of ERK5-mediated expression of DNA damage-induced apoptosis suppressor (DDIAS). In this study, we have revealed a novel mechanism underlying the suppressive effects of L-flow on EC inflammation, migration, proliferation, apoptosis, and fibrotic changes through promoting CHK1-induced SENP2 S344 phosphorylation. The phospho-site mutation SENP2 S344A responds to L-flow through a distinct mechanism, which involves the upregulation of both mesenchymal and EC marker genes.

Reduction of lauric acid content in virgin coconut oil improved plasma lipid profile in high-fat diet-induced hypercholesterolemic mice.

Virgin coconut oil (VCO) is claimed to have various health benefits, but favorable effects of its major component (∼50%), lauric acid, are controversial. Therefore, we aimed to reduce lauric acid content (∼30%) in VCO and evaluate its effect compared to VCO and medium-chain triglycerides (MCT), on food intake, bodyweight (BW), lipid profiles, and hepatic histology. Female C57BL/6 mice were treated with different diets for 3 months: control (normal diet), high-fat diet (HF), HF+VCO, HF+MCT, HF+low lauric acid VCO (LLA), and normal diet+LLA (C+LLA). LLA was prepared by enzymatic interesterification of VCO with methyl octanoate (methyl caprylate) and methyl decanoate (methyl caprate). Plasma and liver lipids, including total cholesterol (TC), high-density lipoprotein (HDL), and triglyceride, were measured by colorimetric assay, and hepatic fat accumulation was examined by oil-red-O staining. HF mice exhibited high plasma and liver TC and low-density lipoprotein (LDL). VCO or MCT treatment lowered liver TC and LDL, whereas LLA increased plasma HDL and markedly improved TC:HDL ratio. The HF-induced hepatic fat accumulation was attenuated by all treatments, of which VCO was the most effective. Control mice administered with LLA demonstrated lower liver TC and LDL, but higher plasma TC and HDL compared to controls. Lowest BW gain and food intake were found in mice treated with LLA. In conclusion, VCO, MCT, and LLA ameliorated hepatic histopathology caused by HF. VCO and MCT improved liver lipid profiles, whereas LLA has more beneficial effect on plasma lipids via a better TC:HDL ratio and showed promise for BW control.

Antihyperlipidemic Activity of Trembesi Leaf Extract (Samanea saman) Against Total and LDL Cholesterol Levels in Hypercholesterolemic Mice

The potential of the trembesi plant (Samanea saman) which is used for traditional medicine includes antibacterial, analgesic, treating headaches and diarrhea [1]. Trembesi leaves are known to have several chemical compounds such as flavonoids, alkaloids, tannins, saponins, and steroids or triterpenoids which are thought to have activity in reducing total cholesterol levels [2]. The aim of this study was to determine the activity and optimal dose of trembesi leaf extract which can reduce total and LDL cholesterol levels in hypercholesterolemic mice. Research method: 25 test mice were divided into 5 groups consisting of group 1 given CMC-NA 1% negative control, group 2 given simvastatin 10 mg positive control, groups 3, 4 and 5 were given extract treatment trembesi leaves with doses of 35 mg/KgBW, 175 mg/KgBW and 350 mg/KgBW. The mice tested were given atherogenic feed and then examined for total and LDL cholesterol levels using the CHOD PAP enzymatic method. Data analysis used the one-way ANOVA test, followed by the post hoc test, namely Duncan's test. Results: Ethanol extract of trembesi leaves at a dose of 175 mg/KgBW can reduce total cholesterol levels by 37.07% and LDL by 50.24%. Conclusion: ethanol extract of trembesi leaves at a dose of 175 mg/KgBW provides an optimal effect on reducing total and LDL cholesterol levels (p<0.05).

Manipulation of components of the renin angiotensin system in renal proximal tubules fails to alter atherosclerosis in hypercholesterolemic mice.

Whole body manipulation of the renin-angiotensin system (RAS) consistently exerts profound effects on experimental atherosclerosis development. A deficit in the literature has been a lack of attention to the effects of sex. Also, based on data with gene-deleted mice, the site of RAS activity that influences lesion formation is at an unknown distant location. Since angiotensin (AngII) concentrations are high in kidney and the major components of the RAS are present in renal proximal tubule cells (PTCs), this study evaluated the role of the RAS in PTCs in atherosclerosis development. Mice with an LDL receptor -/- background were fed Western diet to induce hypercholesterolemia and atherosclerosis. We first demonstrated the role of AT1 receptor antagonism on atherosclerosis in both sexes. Losartan, an AngII type 1 (AT1) receptor blocker, had greater blood pressure-lowering effects in females than males, but equivalent effects between sexes in reducing atherosclerotic lesion size. To determine the roles of renal AT1a receptor and angiotensin-converting enzyme (ACE), either component was deleted in PTCs after weaning using a tamoxifen-inducible Cre expressed under the control of an Ndrg1 promoter. Despite profound deletion of AT1a receptor or ACE in PTCs, the absence of either protein did not influence development of atherosclerosis in either sex. Conversely, mice expressing human angiotensinogen and renin in PTCs or expressing human angiotensinogen in liver but human renin in PTCs did not change atherosclerotic lesion size in male mice. Whole-body AT1R inhibition reduced atherosclerosis equivalently in both male and female mice; however, PTC-specific manipulation of the RAS components had no effects on hypercholesterolemia-induced atherosclerosis.

Lipodystrophic gene Agpat2 deficiency aggravates hyperlipidemia and atherosclerosis in Ldlr−/− mice

AimsDysfunction of adipose tissue increases the risk of cardiovascular disease. It was well established that obesity aggravates atherosclerosis, but the effect of adipose tissue loss on atherosclerosis has been less studied. AGPAT2 is the first causative gene of congenital generalized lipodystrophy (CGL), but the role of AGPAT2 on atherosclerosis has not been reported. Hypertriglyceridemia is one of the clinical manifestations of CGL patients, but it is usually absent in CGL mouse model on a normal diet. This study will investigate the effect of Agpat2 on hyperlipidemia and atherosclerosis. Methods and resultsIn this study, Agpat2 knockout (Agpat2−/−) mice were generated using CRISPR/Cas system, which showed severe loss of adipose tissue and fatty liver, consistent with previous reports. Agpat2−/− mice were then crossed with hypercholesterolemic and atherosclerotic prone LDL receptor knockout (Ldlr−/−) mice to obtain double knockout mouse model (Agpat2−/−Ldlr−/−). Plasma lipid profile, insulin resistance, fatty liver, and atherosclerotic lesions were observed after 12 weeks of the atherogenic high-fat diet (HFD) feeding. We found that compared with Ldlr−/− mice, Agpat2−/−Ldlr−/− mice showed significantly higher plasma total cholesterol and triglycerides after HFD feeding. Agpat2−/−Ldlr−/− mice also developed hyperglycemia and hyperinsulinemia, with increased pancreatic islet area. The liver weight of Agpat2−/−Ldlr−/− mice was about 4 times higher than that of Ldlr−/− mice. The liver lipid deposition was severe and Sirius red staining showed liver fibrosis. In addition, in Agpat2−/−Ldlr−/− mice, the area of atherosclerotic lesions in aortic arch and aortic root was significantly increased. ConclusionsOur results show that Agpat2 deficiency led to more severe hyperlipidemia, liver fibrosis and aggravation of atherosclerosis in Ldlr−/− mice. This study provided additional insights into the role of adipose tissue in hyperlipidemia and atherosclerosis.

Biochemical characterization and hypocholesterolemic properties of sesame yogurt made from deoiled edible quality sesame flour (DEQSF) supplemented with rice bran oil

Despite having a high polyphenol content, deoiled edible quality sesame flour (DEQSF), a byproduct of the sesame oil extraction process, is frequently thrown away. DEQSF contains antioxidants, amino acids, minerals, protein, and many non-nutrient-based health advantages. It could serve as an excellent material for the formulation of a value-added functional food product. The current study developed fortified sesame yogurts using rice bran oil (RBO) and DEQSF at percentages of 6, 7, and 8 in order to compare them to control sesame yogurts manufactured from whole sesame seeds and kept at 4 °C for 28 days. The other goal was to examine the in vivo cholesterol-lowering potential of sesame yogurt prepared from DEQSF and RBO. Evaluations were done on the physicochemical, microbiological, sensory, antioxidative, proteolytic, morphological, and nutritional properties. The proximate composition of RBO-fortified sesame yogurts differed considerably when compared to control yogurt in terms of protein, fat, ash, total solids, and carbohydrate content. After 28 days of storage, the addition of 8% DEQSF not only decreased syneresis but also maintained proper viscosity and penetration properties. The right quantity of probiotic bacteria was present in the RBO-fortified sesame yogurts that contained 8% DEQSF, and RBO-fortified sesame yogurt treated with 8% DEQSF (w/v) had a general overall acceptability score. During storage at 4 °C, all RBO-fortified sesame yogurts had nearly identical antioxidant activity to the control sesame yogurt. The addition of 8% DEQSF increased the amount of proteolysis by Lactobacillus spp. and Streptococcus spp., as evidenced by a significant increase in o-phthaldialdehyde levels. Microstructural studies confirmed the dense, compressed, homogeneous structure of the fortified sesame yogurt. To investigate the effects of RBO-supplemented, DEQSF-based yogurt on hypercholesterolemia, a hypercholesterolemic mice model was developed. Comparing animal groups that received fortified sesame yogurts to control groups, there was a significant effect on serum lipid profile as well as hepatoprotective potential. The implication was that RBO-fortified sesame yogurt could help cure hypercholesterolemia. In the end, it was discovered that 8% DEQSF (w/v) and RBO were the perfect combinations to produce sesame yogurt with an anti-obesity and hypocholesteremic impact.Graphical

Abstract P3095: Il-1 Signaling On Vascular Smooth Muscle Cells Accelerates Atherosclerosis After Murine Kawasaki Disease Vasculitis

Objective: We have previously shown that Lactobacillus casei cell wall extract (LCWE)-induced Kawasaki disease (KD) vasculitis significantly accelerates atherosclerosis in hypercholesterolemic mice. IL-1 signaling is known to play a key role in both KD vasculitis and in the development of atherosclerosis. Here, we investigated the contribution of IL-1 signaling on vascular smooth muscle cells (VSMCs) during KD vasculitis-induced acceleration of atherosclerosis. Methods: Tamoxifen-inducible VSMC-specific IL-1 receptor ( Il1r1) knockout ( Myh11 Cre -ERT2 Il1r1 Δ/Δ )and Il1r1 fl/fl littermate control mice, all on ApoE -/- background, were injected with either PBS or LCWE. Following induction of KD vasculitis, mice were fed a tamoxifen diet for 2 weeks to induce Il1r1 deletion on VSMCs, before being exposed to 8 weeks of Western diet (WD) to promote atherosclerosis. Results: KD vasculitis was associated with a significant acceleration of atherosclerosis, as expected. Specific deletion of Il1r1 on VSMCs reduced this effect, as characterized by significantly decreased plaque size, lipid composition, macrophage infiltration and necrotic core formation in aortic root, as well as diminished lipid accumulation in aorta en face measurements. Conclusions: Our results suggest an important pathophysiologic link between IL-1 signaling, specifically on VSMCs, and subsequent acceleration of atherosclerosis in hypercholesterolemic mice following KD vasculitis. Thus, further studies are warranted on the role of IL-1 signaling not only in acute KD, but also in the subsequent vascular remodeling and complications following acute KD vasculitis.

Cholesterol modulates the physiological response to nanoparticles by changing the composition of protein corona.

Nanoparticles (NPs) in biological fluids form a layer of biomolecules known as the protein corona. The protein corona has been shown to determine the biological identity and in vivo fate of NPs, but whether and how metabolites, especially disease-related small molecules, regulate the protein corona and subsequently impact NP fate in vivo is relatively poorly understood. Here we report on the effects of cholesterol on the generation of protein corona and subsequent effects. We find that high levels of cholesterol, as in hypercholesterolemia, result in a protein corona with enriched apolipoproteins and reduced complement proteins by altering the binding affinity of the proteins to the NPs. The cholesterol-mediated protein corona can induce stronger inflammatory responses to NPs in macrophages and promote the cellular uptake of NPs in hepatocytes by enhancing the recognition of lipoprotein receptors when compared with normal protein corona. The result of in vivo biodistribution assays shows that, compared with healthy mice, NPs in hypercholesterolemic mice were more likely to be delivered to the liver, spleen and brain, and less likely to be delivered to the lungs. Our findings reveal that the metabolome profile is an unexploited factor impacting the target efficacy and safety of nanomedicines, providing a way to develop personalized nanomedicines by harnessing disease-related metabolites.

Induction of lipid-lowering immune reactions by apolipoprotein B-specific T-helper cells in hypercholesterolemic mice

Induction of lipid-lowering immune reactions by apolipoprotein B-specific T-helper cells in hypercholesterolemic mice

Multi‑omics‑based analysis of the regulatory mechanism of gypenosides on bile acids in hypercholesterolemic mice.

Gynostemma pentaphyllum is a traditional medicine used by ethnic minorities in southwest China and gypenosides are currently recognized as essential components of the pharmacological substances of Gynostemma pentaphyllum, which are effective in regulating metabolic syndrome, especially in improving hepatic metabolic disorders. The present study randomly divided C57BL/6J male mice into the normal diet control group (ND), high-fat diet modeling group (HFD) and gypenosides group (GP). Liquid chromatography-mass spectrometry (UPLC-MS) was applied to quantify bile acids in the liver, bile and serum of mice in ND, HFD and GP groups. Liver proteins were extracted for trypsin hydrolysis and analyzed quantitatively using UPLC-MS + MS/MS (timsTOF Pro 2). Total mouse liver RNA was extracted from ND, HFD and GP groups respectively, cDNA sequencing libraries constructed and sequenced using BGISEQ-500 sequencing platform. The expression of key genes Fxr, Shp, Cyp7a1, Cyp8b1, and Abab11 was detected by RT-qPCR. The results showed that gypenosides accelerated free bile acid synthesis by promoting the expression of bile acid synthase CYP7A1 and CYP8B1 genes and proteins and accelerating the secretion of conjugated bile acids from the liver to the bile ducts. GP inhibited the bile acid transporters solute carrier organic anion transporter family member (SLCO) 1A1 and SLCO1A4, reducing the reabsorption of free bile acids and accelerating the excretion of free bile acids from the blood to the kidneys. It also promoted the metabolic enzyme CYP3A11, which accelerated the metabolism and clearance of bile acids, thus maintaining the balance of the bile acid internal environment.

Endothelial autophagy is not required for liver regeneration after partial hepatectomy in mice with fatty liver.

Patients with non-alcoholic fatty liver disease (NAFLD) have impaired liver regeneration. Liver endothelial cells play a key role in liver regeneration. In non-alcoholic steatohepatitis (NASH), liver endothelial cells display a defect in autophagy, contributing to NASH progression. We aimed to determine the role of endothelial autophagy in liver regeneration following liver resection in NAFLD. First, we assessed autophagy in primary endothelial cells from wild type mice fed a high fat diet and subjected to partial hepatectomy. Then, we assessed liver regeneration after partial hepatectomy in mice deficient (Atg5lox/lox ;VE-cadherin-Cre+ ) or not (Atg5lox/lox ) in endothelial autophagy and fed a high fat diet. The role of endothelial autophagy in liver regeneration was also assessed in ApoE-/- hypercholesterolemic mice and in mice with NASH induced by methionine- and choline-deficient diet. First, autophagy (LC3II/protein) was strongly increased in liver endothelial cells following hepatectomy. Then, we observed at 40 and 48 h and at 7 days after partial hepatectomy, that Atg5lox/lox ;VE-cadherin-Cre+ mice fed a high fat diet had similar liver weight, plasma AST, ALT and albumin concentration, and liver protein expression of proliferation (PCNA), cell-cycle (Cyclin D1, BrdU incorporation, phospho-Histone H3) and apoptosis markers (cleaved Caspase-3) as Atg5lox/lox mice fed a high fat diet. Same results were obtained in ApoE-/- and methionine- and choline-deficient diet fed mice, 40 h after hepatectomy. These results demonstrate that the defect in endothelial autophagy occurring in NASH does not account for the impaired liver regeneration occurring in this setting.

MOMAST® Reduces the Plasmatic Lipid Profile and Oxidative Stress and Regulates Cholesterol Metabolism in a Hypercholesterolemic Mouse Model: The Proof of Concept of a Sustainable and Innovative Antioxidant and Hypocholesterolemic Ingredient.

MOMAST® is a patented natural phenolic complex, rich in tyrosol (9.0 g/kg, Tyr), hydroxityrosol (43,5 g/kg, OH-Tyr), and verbascoside (5.0 g/Kg), which is obtained from the OVW by-product of the Coratina cultivar with potent direct antioxidant activity (measured by DPPH and FRAP assays, respectively). Indeed, MOMAST® represents an innovative sustainable bioactive ingredient which has been obtained with ethical and empowering behavior by applying the principles of a circular economy. In the framework of research aimed at fostering its health-promoting activity, in this study it was clearly demonstrated that MOMAST® treatment reduced the oxidative stress and levels of total cholesterol (TC) and low-density lipoprotein (LDL) cholesterol, and increased the HDL levels, without changes in the triglyceride (TG) levels in Western diet (WD)-fed mice. The modulation of the plasmatic lipid profile is similar to red yeast rice (RYR) containing Monacolin K (3%). In addition, at the molecular level in liver homogenates, similarly to RYR, MOMAST® exerts cholesterol-lowering activity through the activation of LDL receptor, whereas, unlike RYR, MOMAST® reduces proprotein convertase subtilisin/kexin type 9 (PCSK9) protein levels via hepatic nuclear factor 1 (HNF1)-α activation. Hence, this study provides the proof of concept regarding the hypocholesterolemic activity of MOMAST, which could be successfully exploited as an active ingredient for the development of innovative and sustainable dietary supplements and functional foods.

Pengaruh Citra Merek Dan Kualitas PelayananTerhadap Keputusan Pembelian Produk Di Optik Zal Soetomo Padang

Hypercholesterolemia is one of the risk factor for cardiovascular disease such as stroke, atherosclerosis and coronary heart disease. The purpose of this study was to determine the effect of ethanol extract of dragon scales leaves (Pyrrosia piloselloides L.) on reducing total cholesterol (TC) of test animals. The instrument to test was 25 male white mice were induced hypercholesterolemia by eating a high fat diet (MDLT) in around 14 days. The animals were declared as hypercholesterolemia if the total of cholesterol level (TC) more than 230 mg/dl. Then the Animals divided into five groups namely positive control, comparison (simvastatin), and the group given the test extract doses of 25, 50, 100 mg/kgBB. The treatment was given for 15 days, and TC level were checked on days 0, 5, 10 and 15. The data were analyzed by Two Way of ANOVA and continued with Duncan's test. The results showed that the dose of the tested extract and the duration of administration had a significant effect (p<0.05) on reduce in TC levels of the test animals. All variations in the doses of ethanol extract from dragon scale leaves had the effect to reduce TC in the animals and the percentage reduction value was equal to the group given simvastatin. These results indicate that the ethanol extract of dragon scales leaves has the potential to reduce total cholesterol levels in hypercholesterolemic mice.

An ERK5-NRF2 Axis Mediates Senescence-Associated Stemness and Atherosclerosis.

ERK5 (extracellular signal-regulated kinase 5) is a dual kinase transcription factor containing an N-terminal kinase domain and a C-terminal transcriptional activation domain. Many ERK5 kinase inhibitors have been developed and tested to treat cancer and inflammatory diseases. However, recent data have raised questions about the role of the catalytic activity of ERK5 in proliferation and inflammation. We aimed to investigate how ERK5 reprograms myeloid cells to the proinflammatory senescent phenotype, subsequently leading to atherosclerosis. A ERK5 S496A (dephosphorylation mimic) knock in (KI) mouse model was generated using CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9), and atherosclerosis was characterized by hypercholesterolemia induction. The plaque phenotyping in homozygous ERK5 S496A KI and wild type (WT) mice was studied using imaging mass cytometry. Bone marrow-derived macrophages were isolated from hypercholesterolemic mice and characterized using RNA sequencing and functional in vitro approaches, including senescence, mitochondria reactive oxygen species, and inflammation assays, as well as by metabolic extracellular flux analysis. We show that atherosclerosis was inhibited in ERK5 S496A KI mice. Furthermore, ERK5 S496 phosphorylation mediates both senescence-associated secretory phenotype and senescence-associated stemness by upregulating AHR (aryl hydrocarbon receptor) in plaque and bone marrow-derived macrophages isolated from hypercholesterolemic mice. We also discovered that ERK5 S496 phosphorylation could induce NRF2 (NFE2-related factor 2) SUMOylation at a novel K518 site to inhibit NRF2 transcriptional activity without altering ERK5 catalytic activity and mediates oxidized LDL (low-density lipoprotein)-induced senescence-associated secretory phenotype. Specific ERK5 kinase inhibitors (AX15836 and XMD8-92) also inhibited ERK5 S496 phosphorylation, suggesting the involvement of ERK5 S496 phosphorylation in the anti-inflammatory effects of these ERK5 kinase inhibitors. We discovered a novel mechanism by which the macrophage ERK5-NRF2 axis develops a unique senescence-associated secretory phenotype/stemness phenotype by upregulating AHR to engender atherogenesis. The finding of senescence-associated stemness phenotype provides a molecular explanation to resolve the paradox of senescence in proliferative plaque by permitting myeloid cells to escape the senescence-induced cell cycle arrest during atherosclerosis formation.

Alleviation Syndrome of High-Cholesterol-Diet-Induced Hypercholesterolemia in Mice by Intervention with Lactiplantibacillus plantarum WLPL21 via Regulation of Cholesterol Metabolism and Transportation as Well as Gut Microbiota.

Probiotics are prospective for the prevention and treatment of cardiovascular diseases. Until now, systematic studies on the amelioration of hypercholesterolemia have been rare in terms of (cholesterol metabolism and transportation, reshaping of gut microbiota, as well as yielding SCFAs) intervention with lactic acid bacteria (LAB). In this study, strains of Lactiplantibacillus plantarum, WLPL21, WLPL72, and ZDY04, from fermented food and two combinations (Enterococcus faecium WEFA23 with L. plantarum WLPL21 and WLPL72) were compared for their effect on hypercholesterolemia. Comprehensively, with regard to the above aspects, L. plantarum WLPL21 showed the best mitigatory effect among all groups, which was revealed by decreasing total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels, upregulated cholesterol metabolism (Cyp27a1, Cyp7b1, Cyp7a1, and Cyp8b1) levels in the liver, cholesterol transportation (Abca1, Abcg5, and Abcg8) in the ileum or liver, and downregulated Npc1l1. Moreover, it reshaped the constitution of gut microbiota; specifically, the ratio of Firmicutes to Bacteroidetes (F/B) was downregulated; the relative abundance of Allobaculum, Blautia, and Lactobacillus was upregulated by 7.48-14.82-fold; and that of Lachnoclostridium and Desulfovibrio was then downregulated by 69.95% and 60.66%, respectively. In conclusion, L. plantarum WLPL21 improved cholesterol metabolism and transportation, as well as the abundance of gut microbiota, for alleviating high-cholesterol-diet-induced hypercholesterolemia.

Glial cell reactivity drives cognitive decline in LDLr‐/‐ mice: experimental evidences

AbstractBackgroundFamilial hypercholesterolemia (FH) is a clinical condition characterized by increased plasma cholesterol levels, due to a mutation in the gene encoding the low‐density lipoprotein receptor (LDLr) in cells [Brown and Goldstein, 1984]. Importantly, clinical evidence indicates that FH negatively affects cognition and favors the development of neuropathologies [Ariza et al., 2016; Zambón et al, 2010], however, the mechanisms behind this relationship are still not fully understood. In this study we aimed to investigate the role of glial cell reactivity on the cognitive deficits related to the FH, as well as the possible neuroprotective effect of a pharmacological inhibitor of microglial cell activation.MethodFirstly, male 3‐months‐old and 14‐months‐old C57BL/6 wild‐type and LDLr knockout mice (LDLr‐/‐) mice brains were prepared for the evaluation of glial cell morphology by immunofluorescence. In addition, the mice’s hippocampus was removed to measure the immune content of synaptic and tight‐junctions proteins. Moreover, male and female 6‐months‐old C57BL/6 wild‐type and LDLr‐/‐ mice were treated with minocycline (50 mg/kg) or vehicle (saline) for four weeks. Afterwards, mice were submitted to behavioral tests.ResultMiddle‐aged LDLr‐/‐ mice (14‐months‐old) exhibited increased microgliosis in hippocampus, which was correlated with morphological change of microglial cells and astrocytes in this same brain region. Also, middle‐aged LDLr‐/‐ mice presented a reduction in the immune content of synaptophysin‐1 in the hippocampus. Moreover, young adult (3‐months‐old) LDLr‐/‐ mice exhibited reduced immune content of PSD95 in the hippocampus. Finally, the administration of minocycline to 6‐months‐old LDLr‐/‐ mice ameliorated the performance of hypercholesterolemic mice in hippocampal‐dependent memory tasks, without modifying their locomotor activity and metabolic parameters.ConclusionTaken together, our results demonstrated that FH alters the glial cell reactivity, which was associated with changes in synaptic proteins in the hippocampus. In addition, the pharmacological modulation of microglial cell reactivity ameliorated the hippocampal‐dependent memory in LDLr‐/‐ mice, suggesting that increased glial cell reactivity is a key event for HF‐related cognitive deficits.

Transcriptional analysis reveals that the intracellular lipid accumulation impairs gene expression profiles involved in insulin response-associated cardiac functionality

Cardiovascular disease (CVD) is a multisystemic and multicellular pathology that is generally associated with high levels of atherogenic lipoproteins in circulation. These lipoproteins tend to be retained and modified, for example, aggregated low-density lipoprotein (aggLDL), in the extracellular matrix of different tissues, such as the vascular wall and heart. The uptake of aggLDL generates a significant increase in cholesteryl ester (CE) in these tissues. We previously found that the accumulation of CE generates alterations in the insulin response in the heart. Although the insulin response is mainly associated with the uptake and metabolism of glucose, other studies have shown that insulin would fulfill functions in this tissue, such as regulating the calcium cycle and cardiac contractility. Here, we found that aggLDL induced-lipid accumulation altered the gene expression profile involved in processes essential for cardiac functionality, including insulin response and glucose uptake (Insr, Ins1, Pik3ip1, Slc2a4 gene expression), calcium cycle (Cacna1s and Gjc2 gene expression) and calcium-dependent cardiac contractility (Myh3), and cholesterol efflux (Abca1), in HL-1 cardiomyocytes. These observations were recapitulated using an in vivo model of hypercholesterolemic ApoE-KO mice. Altogether, these results may explain the deleterious effect of lipid accumulation in the myocardium, with important implications for lipid-overloaded associated CVD, including impaired insulin response, disrupted lipid metabolism, altered cardiac structure, and increased susceptibility to cardiovascular events.