Plasma LDL Levels Research Articles

Investigation of fructose consumption on hippocampal insulin and glucagon-like peptide-1 receptors, and metabolic effects in rats.

The detrimental effects of high fructose consumption on metabolic health have been extensively studied. However, limited research has focused on the impact of fructose intake on neuroprotective mechanisms, specifically the expression of insulin receptor (INSR) and glucagon-like peptide-1 receptor (GLP-1R) in the hippocampus. Understanding the effects of fructose on these neuroprotective molecules can provide valuable insights into the potential role of fructose in hippocampal dysfunction. The goal of this study is to aim at the basal plasma levels of lipid profile, insulin, GLP-1, and HOMA-IR, as well as the mRNA and protein expression of neuroprotective molecules such as INSR and GLP-1R in Wistar rats fed a high fructose diet. Rats were separated into control (C) and high fructose (HF) groups. The HF group was given 20% fructose water to drink for 16 weeks. Fructose ingestion significantly increased abdominal fat (C=1.24±0.08 g, HF=1.79±0.19 g, P<0.05) and plasma triglyceride levels (C=179.22±22.85 µg/ml, HF=242.45±14.45 µg/ml, P<0.05), but had no statistically significant effect on body weight and plasma HDL, LDL, total cholesterol, insulin, and GLP-1 levels (P>0.05). Although INSR mRNA expression in the hippocampus was significantly lower in the HF group compared to the control group (P<0.05), GLP-1R mRNA expression did not differ significantly across the groups (P>0.05). Furthermore, whereas INSR and GLP-1R protein levels in the experimental group were on a declining trend, this trend was not substantially different (P>0.05). These data suggest that fructose consumption may be harmful to the hippocampus by lowering the expression of INSR.

Combined Therapy with Simvastatin- and Coenzyme-Q10-Loaded Nanoparticles Upregulates the Akt-eNOS Pathway in Experimental Metabolic Syndrome.

In addition to their LDL-cholesterol-lowering effect, statins have pleiotropic beneficial effects on the cardiovascular system. However, long-term treatment with statins may be associated with serious side effects. With the aim to make statin therapy more effective, we studied the effects of simvastatin- and coenzyme-Q10-loaded polymeric nanoparticles on the lipid profile and nitric oxide (NO)/reactive oxygen species (ROS) balance in the heart and aorta of adult male obese Zucker rats. The rats were divided into an untreated group, a group treated with empty nanoparticles, and groups treated with simvastatin-, coenzyme Q10 (CoQ10)-, or a combination of simvastatin- and CoQ10-loaded nanoparticles (SIMV+CoQ10). After 6 weeks, the lipid profile in the plasma and the concentration of conjugated dienes in the liver were determined. Nitric oxide synthase (NOS) activity, Akt, endothelial NOS (eNOS), phosphorylated eNOS (p-eNOS), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and nuclear factor kappaB (NF-kappaB) protein expressions were measured in the heart and aorta. All simvastatin, CoQ10, and SIMV+CoQ10 treatments decreased plasma LDL levels, but only the combined SIMV+CoQ10 treatment increased NOS activity and the expression of Akt, eNOS, and p-eNOS in both the heart and the aorta. Interestingly, NADPH oxidase in the heart and NF-kappaB protein expression in the aorta were decreased by all treatments, including nanoparticles alone. In conclusion, only combined therapy with SIMV- and CoQ10-loaded nanoparticles increased NOS activity and upregulated the Akt-eNOS pathway in obese Zucker rats, which may represent a promising tool for the treatment of cardiometabolic diseases.

91 METABOLIC AND CARDIAC MORPHO-FUNCTIONAL IMPROVEMENTS AFTER PCSK9 INHIBITORS ADMINISTRATION

Abstract Aim Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) is mainly produced by the liver, but it is also expressed in the heart. It plays a key role in cholesterol's metabolism. Recent studies suggest its possible role in cardiovascular (CV) diseases, promoting vascular inflammation, reactive oxygen species generation and atherosclerotic plaque formation. Global longitudinal strain (GLS), global myocardial work efficiency (GWE), reservoir (PALS) and pump (PACS) atrial function evaluated by speckle-tracking echocardiography are able to identify early subclinical ventricular and atrial myopathy. In the last years PCSK9 inhibitors have been introduced as innovative therapies for LDL plasma levels's reduction. The aim of our study was to investigate PCSK9 inhibitors's effects in secondary prevention's patients, equally assigned to Alirocumab or Evolocumab, who were statin-intolerant and/or not reaching the target of LDL-C &amp;lt;55 mg/dl using the maximum tolerated drugs’ dosage at basal time and on semestral follow-up. Methods We selected 30 patients (24 males and 6 females, mean age 66+8 years old), having several comorbidities: hypertension (97%), ICM (90%), CKD II-III stage (70%), polidistrectual atherosclerosis (67%), T2DM (50%), OSAS-COPD (20%), HF NYHA class II-III (20%). They underwent anthropometrical evaluation, biochemical analysis, oxidative stress markers assessment, liver elastography, and advanced echocardiogram at basal time and after six months of therapy. NOX-2 and Sp-selectin were assessed with ELISA sandwich. Data were analyzed with ANOVA, post-hoc Bonferroni's test and Chi-square. Linear correlation analysis was performed for variables whose variation were statistically significant. Results As expected, lipid profile was greatly improved in all the subjects, reaching the target of LDL-C &amp;lt;55 mg/dl. We obtained a statistically significant reduction of total-cholesterol (32%, p&amp;lt;0,0001), LDL-C (60%, p&amp;lt;0,0001), TG (26%, p&amp;lt;0,0001), TG/HDL ratio (27%, p&amp;lt;0,0001); an increase of HDL-C (9%, p=0.001) and an improvement of glomerular filtrate evaluated by CKD-EPI (6%, p=0.007). We observed a statistically significant reduction of NOX-2 (27%, p&amp;lt;0,0001) and Sp-selectin (36%, p&amp;lt;0,0001). We obtained a statistically significant increase of PALS (16.9%, p&amp;lt;0,0001), PACS (21%, p&amp;lt;0,0001), GWE (9.7%, p&amp;lt;0,0001), GLS (24%, p&amp;lt;0,0001) and a statistically significant reduction of global wasted work (GWW; 15%, p&amp;lt;0,0001), left atrial volume index (LAVI; 8%, p&amp;lt;0,0001) and E/e’ ratio (19%, p&amp;lt;0,0001). The results of linear correlation analysis showed that PACS was significantly and inversely correlated with TG/HDL (r=-0.406, p=0.013) and NOX-2 (r=-0.416, p=0.011); PALS was significantly and inversely correlated with TG/HDL (r=-0.473, p=0.004) and NOX-2 (r=-0.435, p=0.008); E/e’ was significantly and directly correlated with TG/HDL (r=0.654, p&amp;lt;0.0001) and NOX-2 (r=0.438, p=0.008); GWE was inversely correlated with NOX-2 (r=-0.422, p=0.01). Conclusions Our study demonstrated for the first time that PCSK9 inhibitors are able to reduce left ventricular filling pressure, to increase atrial function (reservoir and pump), global cardiac performance (GLS and GWE), and eGFR after six months of treatment in high CV risk population. Our results could be partially explained with a reduction of oxidative stress markers, inflammation and cardio-lipotoxicity, probably linked to a modulation of PCSK9's heart expression and its toxic effect on CV and renal function. In addition, we observed a TG/HDL ratio's reduction, related to cardiometabolic and lipid profile improvement. Further studies are necessary to better investigate systemic benefit in a larger population with longer follow-up.

Rosa26-LSL-dCas9-VPR: a versatile mouse model for tissue specific and simultaneous activation of multiple genes for drug discovery

Transgenic animals with increased or abrogated target gene expression are powerful tools for drug discovery research. Here, we developed a CRISPR-based Rosa26-LSL-dCas9-VPR mouse model for targeted induction of endogenous gene expression using different Adeno-associated virus (AAV) capsid variants for tissue-specific gRNAs delivery. To show applicability of the model, we targeted low-density lipoprotein receptor (LDLR) and proprotein convertase subtilisin/kexin type 9 (PCSK9), either individually or together. We induced up to ninefold higher expression of hepatocellular proteins. In consequence of LDLR upregulation, plasma LDL levels almost abolished, whereas upregulation of PCSK9 led to increased plasma LDL and cholesterol levels. Strikingly, simultaneous upregulation of both LDLR and PCSK9 resulted in almost unaltered LDL levels. Additionally, we used our model to achieve expression of all α1-Antitrypsin (AAT) gene paralogues simultaneously. These results show the potential of our model as a versatile tool for optimized targeted gene expression, alone or in combination.

Potential novel biomarkers in small intestine for obesity/obesity resistance revealed by multi-omics analysis

BackgroundAlthough obesity is caused by different factors, individual susceptibility to obesity differs among people under the same circumstances. The microbiota in the caecum or fresh faeces and metabolites in blood or urine contribute to obesity resistance; however, the microbiota or metabolites in the small intestine have not been extensively studied.MethodsTo investigate the relationship between the microbiota or metabolites in the small intestine and susceptibility to obesity, eighty-eight male C57BL/6 mice were fed a high-fat diet (HFD) for 8 weeks to establish two models of obesity and obesity resistance. For further study, six mice were chosen from among the obesity models, and twelve mice were randomly chosen from among the obesity resistance models. After fasting plasma glucose and behavioural testing, the mice were fed in single cages for another 4 weeks to observe their weight and food intake. All mice were sacrificed at 20 weeks of age. Serum ALT, AST, HDL, LDL, TG and TC levels were measured using an automatic biochemical analyser. The microbiota and metabolites in the small intestine contents were analysed using 16 S sequencing and an ultrahigh-performance liquid chromatographic system, respectively. Transcripts in the jejunum were evaluated using full-length transcriptome sequencing and verified by qPCR.ResultsThe results showed that HFD induced depression and anxiety behaviours and higher fasting plasma glucose, ALT, AST, HDL, LDL, TG and TC levels in the obese mice; however, these levels were improved in obese resistance mice. The correlation analysis showed that the phosphatidylcholine, TG, and phosphatidylethanolamine levels were higher in obese mice and correlated positively with intestinal microflora (Desulfovibrio and Gemella) and the Cxcl10 gene. A higher abundance of Clostridium_sensu_stricto_1 in obesity-resistant mice correlated negatively with the metabolite contents (neuromedin N and enkephalin L) and Pck1 gene expression and correlated positively with certain metabolites (5-hydroxy-L-tryptophan, cinnamyl alcohol and 1 H-indole-3-acetamide) and genes expression (Gdf15, Igfbp6 and Spp1).ConclusionClostridium_sensu_stricto_1, neuromedin N, enkephalin L, Pck1, 5-hydroxy-L-tryptophan, Cxcl10 and cinnamyl alcohol may be novel biomarkers in the small intestine for obesity/obesity resistance. These might be helpful for obesity prevention or for treating obese patients.

Assessment of serum lipid profile in patients with oral potentially malignant disorders

Background: To assess the serum lipid profile in oral potentially malignant disorder patients. Materials & methods: A total of 40 subjects were enrolled. Age of the patients was 40 to 70 years. 20 clinically diagnosed with oral potentially malignant disorders were included in this study. 20 healthy individuals, who had no complaint or any major illness in the recent past, were included in the study as controls. Laboratory investigations were done. Blood samples were collected. Plasma levels of cholesterol, triglycerides, and HDL were calculated. Result was analysed using SPSS software. Results: In group I, the triglycerides level was 135.62 mg/dl and in group II, the triglycerides level was 195.3 mg/dl. A statistically significant P < 0.001, decrease in mean plasma triglyceride level is observed in the oral potentially malignant disorder (OPMD) group as compared with the control group. In group I, levels of HDL, LDL and VLDL were 50.62 mg/dl, 90.36 mg/dl and 22.63 mg/dl whereas in control group the levels were 74.82 mg/dl, 108.46 mg/dl and 34.66 mg/dl respectively. Statistically significant P < 0.001 decrease of plasma LDL levels is observed in the oral potentially malignant disorder as compared to the control group. Conclusion: The change in lipid levels can have a diagnostic role in oral potentially malignant disorder patients.

Biological targets of berberine hydrochloride and the mechanisms by which it alleviates metabolic-associated fatty liver disease

<p indent="0mm">Metabolic-associated fatty liver disease (MAFLD) is a common disease worldwide and is closely related to cardiovascular disease, obesity, diabetes and other metabolic diseases. However, there is no efficient medication available yet. Researches on potential drugs, including antioxidants, insulin sensitizers and lipid-lowering drugs, have indicated that these drugs are effective in reducing the liver fat content and some histological lesions but have limited effects in alleviating liver fibrosis. Berberine hydrochloride (BBR) is an isoquinoline alkaloid derived from many medicinal plants. It was used as an anti-diarrhoea drug in the early stage. However, a large number of studies have shown that it has rich pharmacological effects in the protection against cardiovascular diseases, cancers and other aspects. Increasing evidence has indicated that BBR can regulate metabolism and has beneficial effects on MAFLD. In the target organ of the liver, BBR can activate AMPK by regulating the phosphorylation of AMPK. This phosphorylation inhibits the expression of downstream genes related to lipid synthesis and metabolism, and thus improves hepatic steatosis. The mitochondrial membrane protein UCP2 is considered to be one of the key proteins in reducing fatty liver that acts by targeting liver mitochondria to improve cellular oxidative stress. Improving insulin resistance may also be one of the important mechanisms by which BBR alleviates MAFLD. This mechanism is mainly related to the glucose transporter and insulin resistance-related protein IRS. However, BBR is absorbed and first eliminated in the small intestine. More than 99% of BBR does not enter the bloodstream. It is speculated that BBR mainly plays a biological role in alleviating hepatic steatosis by acting through the intestinal tract, but the specific mechanism and target of BBR remain unclear. Some studies have indicated that the effect of BBR on the improvement of the intestinal microenvironment and the inhibition of intestinal lipid uptake may be the key mechanism. BBR can alleviate MAFLD by improving intestinal dysregulation, reducing blood lipids and inflammatory cytokines, and restoring bile acids. In addition, BBR, absorbed by intestinal epithelial cells, can regulate intestinal lipid uptake. Soat2 may be an important regulatory target of BBR in the intestine. By regulating Soat2, BBR can inhibit the expression of proteins related to lipid uptake in the intestinal epithelium and inhibit the uptake of free fatty acids and cholesterol in the intestinal tract. Recent studies have found that Soat2 is a target gene of hepatic X receptor (LXRα) transcriptional regulation. If the LXR inverse activator acts only in the gut, it can effectively inhibit Soat2 expression, reduce cholesterol reabsorption, and lower plasma LDL levels. Therefore, the LXR-SOAT2 regulatory mechanism may also be involved in the regulation of fatty acid uptake in the gut by BBR. In this review, we briefly summarize the mechanism by which BBR acts in the direct regulation of liver lipid metabolism, including activating the AMPK pathway and alleviating liver inflammation and oxidative stress. A potential biological target of BBR in the intestinal tract that could ameliorate MAFLD by improving the intestinal microenvironment and inhibiting intestinal lipid uptake was also reviewed.

Recent Update on PCSK9 and Platelet Activation Experimental Research Methods: In Vitro and In Vivo Studies.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a crucial factor in the development and progression of cardiovascular diseases. PCSK9 has been demonstrated to modify LDL plasma levels and increase platelet activation, which promotes atherosclerosis, a defining feature of nearly all cardiovascular diseases. Platelet activation has been shown to promote and maintain the response to atherosclerosis development, from beginning to progression and exacerbation, which can lead to advanced cardiovascular events including myocardial infarction (MI) or death. Research on PCSK9 and platelet activation is currently underway with the main goal of reducing the risk of advanced cardiovascular events by preventing or slowing down atherosclerosis progression. Both in vitro and in vivo studies have been used to explore PCSK9 functions to develop new drugs targeting PCSK9. Finding the most suitable study models that represent the pathological and physiological systems found in humans is very important to achieving the goal. This review aimed to present a current and comprehensive overview of the experimental models that have been used to investigate the role of PCSK9 in platelet activation-induced atherosclerotic cardiovascular diseases.

Impact of dietary sucralose and sucrose-sweetened water intake on lipid and glucose metabolism in male mice.

Overconsumption of sugar-sweetened beverages (SSBs) is associated with an increased risk of metabolic disorders, including obesity and diabetes. However, accumulating evidence also suggests the potential negative impact of consuming nonnutritive sweeteners (NNSs) on weight and glycaemic control. The metabolic effects of sucralose, the most widely used NNS, remain controversial. This study aimed to compare the impact of intake of dietary sucralose (acceptable daily intake dose, ADI dose) and sucrose-sweetened water (at the same sweetness level) on lipid and glucose metabolism in male mice. Sucralose (0.1mg/mL) or sucrose (60mg/mL) was added to the drinking water of 8-week-old male C57BL/6 mice for 16weeks, followed by oral glucose and intraperitoneal insulin tolerance tests, and measurements of bone mineral density, plasma lipids, and hormones. After the mice were sacrificed, the duodenum and ileum were used for examination of sweet taste receptors (STRs) and glucose transporters. A significant increase in fat mass was observed in the sucrose group of mice after 16weeks of sweetened water drinking. Sucrose consumption also led to increased levels of plasma LDL, insulin, lipid deposition in the liver, and increased glucose intolerance in mice. Compared with the sucrose group, mice consuming sucralose showed much lower fat accumulation, hyperlipidaemia, liver steatosis, and glucose intolerance. In addition, the daily dose of sucralose only had a moderate effect on T1R2/3 in the intestine, without affecting glucose transporters and plasma insulin levels. Compared with mice consuming sucrose-sweetened water, daily drinking of sucralose within the ADI dose had a much lower impact on glucose and lipid homeostasis.

PCSK9 is differentially distributed among HDL subpopulations

Background and Aims : PCSK9 plays a crucial role to LDL-R binding in hepatocytes, LDL-R regulation, and increased plasma LDL levels. Plasma PCSK9 is associated with LDL and Lp(a), whereas a recent study showed that PCSK9 is mostly carried by HDL. The aim of this study was to determine the PCSK9-HDL association.

Perinatal stress exposure induced oxidative stress, metabolism disorder, and reduced GLUT-2 in adult offspring of rats.

Growing evidence has demonstrated that adversity in early life, especially in the prenatal and postnatal period, may change the programming of numerous body systems and cause the incidence of various disorders in later life. Accordingly, this experimental animal study aimed to investigate the effect of stress exposure during perinatal (prenatal and/or postnatal) on the induction of oxidative stress in the pancreas and its effect on glucose metabolism in adult rat offspring. In this experimental study based on maternal exposure to variable stress throughout the perinatal period, the pups were divided into eight groups, as follows: control group (C); prepregnancy, pregnancy, lactation stress group (PPPLS); prepregnancy stress group (PPS); pregnancy stress group (PS); lactation stress group (LS); prepregnancy, pregnancy stress group (PPPS); pregnancy, lactation stress group (PLS); and prepregnancy, lactation stress group (PPLS). Following an overnight fast on postnatal day (PND) 64, plasma glucose, insulin, leptin levels, and lipid profiles were evaluated in the offspring groups. GLUT-2 protein levels, lipid peroxidation, antioxidant status, and number of beta-cells in the pancreatic islets of Langerhans as well as the weights of intra-abdominal fat and adrenal glands were assessed. Levels of plasma corticosterone were determined in the different groups of mothers and offspring. The levels of plasma corticosterone, insulin, and HOMA-B index increased, whereas glucose level and QUICKI index were reduced in the perinatal stress groups compared to C group (p < 0.001 to p < 0.05). Plasma triglyceride, LDL, and cholesterol level rose significantly, but HDL level decreased in the perinatal stress groups compared to C group (p < 0.001 to p < 0.05). Perinatal stress raised MDA concentrations and reduced the activities of antioxidant enzymes in plasma and pancreas compared to C group (p < 0.001 to p < 0.05). GLUT-2 protein levels and number of beta-cells in the stress groups declined compared to C group (p < 0.001 to p < 0.05). Intra-abdominal fat weight decreased in the PPS, PS, and LS groups compared to C group (p < 0.001 to p < 0.01), but adrenal gland weight remained unchanged. Our results showed that long-term exposure to elevated levels of corticosterone during critical development induces metabolic syndrome in adult male rats.

HR-LCMS Analysis and Antihyperlipidemic Effect of Ethanolic Leaf Extract of Momordica charantia L.

Momordica charantia L. (Bitter melon) has been used to treat hyperglycemia and hyperlipidemia in many parts of the world. The present study revealed antihyperlipidemic activity of ethanolic leaf extract of M. charantia L. (named as EMC). The ethanolic extract of leaves were prepared and phytochemical constituents were identified using liquid chromatography linked with mass spectrophotometry. LCMS study indicates the presence of phenolic compound (m-hydroxy benzoic acid, octyl gallate, 3-hydroxycoumarin), triterpenoids (momordicin II, momordicoside E and momordicoside K), saponin E and fatty acids were the major constituents in EMC. Whereas, Triton X-100 induced hyperlipidemic rats model was used to evaluate antihyperlipidemic activity of EMC at a dose of 50, 100 and 200 mg/kg, b.w. or atorvastatin (10 mg/kg, b.w.). The plasma total cholesterol, triglycerides, HDL, LDL and VLDL level, hepatic cholesterol and triglyceride, fecal cholesterol and triglycerides level were checked. Triton X-100 significantly (P < 0.01) increased the serum total cholesterol, triglycerides and LDL with a concomitant reduction in HDL cholesterol. These alterations were ameliorated by EMC at dose dependant manner. EMC (200 mg/kg, b.w) showed significant (P < 0.01) reduction in lipid level among three doses of extracts in comparison with the standard drug atorvastatin. Overall results findings suggest that bitter melon may have potential to use as supplementary ingredient for the prevention of hyperlipidemia and related conditions.

Hypoglycemic, Hypolipidemic, and Anti-Inflammatory Effects of Beta-Pinene in Diabetic Rats.

Background Diabetes is a metabolic disease linked to multiple comorbidities, such as low-grade inflammation. β-pinene, a monoterpene commonly found in aromatic plants, is endowed with anti-inflammatory effect and this fact lead us to investigate the possible hypoglycemic, hypolipidemic and anti-inflammatory effects of the monoterpene in the alloxan-induced diabetes experimental model. Methods Male Wistar rats (200–250 g) were treated orally with β-pinene (25, 50, 100, and 200 mg/kg) or glibenclamide (5 mg/kg), for seven consecutive days. Diabetes was induced by alloxan (40 mg/kg) through the penile vein. On the seventh day of treatment, blood samples were collected for biochemical analysis. The anti-inflammatory effect of β-pinene was evaluated using the carrageenan-induced paw edema model, followed by the carrageenan-induced peritonitis. Results The treatment with β-pinene decreased plasma glucose, triglyceride, VLDL, LDL, and HDL levels, when compared to those of the control group. In addition, the association β-pinene 10 mg/kg + glibenclamide 2 mg/kg significantly decreased blood glucose, total cholesterol, and triglyceride level. Finally, oral treatment with β-pinene reduced carrageenan-induced paw edema and leukocyte migration in the peritoneum. Taken together, our results indicate that β-pinene shows hypoglycemic and hypolipemic effects, which may involve some common mechanisms of glibenclamide. Besides, the monoterpene presented an anti-inflammatory action in diabetic rats that needs further investigation in order to clarify such effect and its correlation with the alterations observed in plasma parameters of β-pinene-treated diabetic rats.

Abstract 420: Proprotein Convertase Subtilisin/Kexin 6 Is Involved In Lipid Metabolism In Liver

Introduction: PCSK6 is a protease that activates cytokines and growth factors and strongly enriched in healthy human liver, however its function in this context has not been explored. We have previously shown that PCSK6 is induced in atherosclerotic plaques from patients with symptoms of stroke and important for regulating several cell types in this context. Here, we aimed to investigate the role of PCSK6 in lipid metabolism in liver, particularly in the context of atherosclerosis and non-alcoholic fatty liver disease (NAFLD). Methods: We used publically available datasets and several atherosclerosis biobanks to investigate the expression of PCSK6 in healthy and diseased human tissues. In addition, we used full Pcsk6 -/- mice as well as liver specific conditional Pcsk6 -/- knockout mice compared to littermate controls, to investigate the effects of PCSK6 ablation on lipid metabolism. Results: Genetic analyses of the PCSK6 locus identified a variant, rs7181043, that was significantly associated with PCSK6 mRNA expression in healthy human adipose tissue, liver and in atherosclerotic plaques. The same variant was associated specifically with plaque fat content and atherosclerotic patient’s plasma LDL levels. In addition, PCSK6 mRNA expression in plaques was positively correlated with total plasma cholesterol and LDL levels in atherosclerotic patients as well as lipid metabolism associated pathways within the carotid plaque. Microarray comparison of the livers from Pcsk6 -/- mice and controls showed that VLDL particle assembly was one of the upregulated processes. I n vivo studies showed that Pcsk6 -/- mice have higher plasma cholesterol and LPL levels at baseline compared to controls, and lower levels of LDLR in their liver. These findings were further confirmed in liver specific conditional knockouts. Preliminary results show that liver specific knockout mice develop increased liver steatosis and fibrosis on a modified western diet. Conclusions: Our data suggests that PCSK6 is involved in cholesterol and metabolic control in liver. Breeding of liver specific Pcsk6 knockout mice on an ApoE -/- background is currently ongoing and will provide insight into the role of liver PCSK6 in atherosclerosis and NAFLD development.

Obesity‐induced and LDL‐mediated NK Cell Function Loss is Accompanied by Proteasome‐dependent induction of Lysophagy in an at‐risk population of African American Women

Obesity and related chronic diseases (i.e. cardiovascular disease (CVD) and cancer) disproportionately affect African Americans (AA), shortening life expectancy and impacting quality of life. Life‐long exposure to adverse social determinants of health (SDoH) have been linked to obesity, warranting intensified research to further elucidate the ‘biology of adversity’ or the biologic consequences of adverse social conditions. Evidence suggests that exposure to chronic psychological and environmental stressors as SDoH leads to immune cell dysfunction, particularly for Natural Killer (NK) cells. Therefore, we examined changes in NK cell function in AA women, a group at high risk of Class III obesity (BMI ≥40 kg/m2). We have previously shown that NK cell degranulation is impaired in AA women with Class III obesity accompanied by a decrease in IFNg and TNFa, a loss in function driven by plasma LDL levels (b=‐0.35, p=0.03). A similar phenotype of dysfunctional NK cells could be achieved by overnight LDL treatment (50mg/dl) of healthy donor NK cells. To further determine the underlying signaling pathways, we employed proteomics of control and LDL treated NK cells. Here we identified 18 statistically significant regulated proteins (p&lt;0.05), and 23 proteins approaching significance (p&lt;0.07). Signaling pathway analysis revealed endolysosomal function, actin cytoskeleton regulation, and regulation of innate immune responses as significant pathways. Several proteins associated with autophagy and ubiquitination were also identified. This is of particular importance as LDL treatment of various cell types has been related to damaging lysosomes and a subsequent potential induction of lysophagy. Therefore, we investigated the impact of LDL on NK cell autophagy through western blot analysis of LC3 and p62 and found that enhanced autophagy is present in LDL treated NK cells. By employing the proteasome inhibitor MG‐132, we also found that the LDL‐induced increase in autophagy appears to be dependent on the activation of the 20S proteasome and subsequent ubiquitination of lysosomal proteins which results in depletion of functional lysosomes through lysophagy and is accompanied by NK cell function loss. In summary, we show a novel pathway potentially explaining obesity‐related NK cell function loss as a result of adverse SDoH in a population at highest risk for obesity‐related diseases like CVD and cancer. In the future, more research is needed to further understand the ‘biology of adversity’ and identifying targets for tailored interventions, ultimately reducing health inequities in chronic disease outcomes.

Effect of glucagon-like peptide-1 receptor agonists on body weight in adults with obesity without diabetes mellitus-a systematic review and meta-analysis of randomized control trials.

Clinical trials have investigated the weight loss effect of glucagon-like peptide-1 receptor agonists (GLP-1 RA) in adults with obesity without diabetes mellitus, but results for weight loss efficacy were varied. We aimed to provide an up-to-date systematic review and meta-analysis for overall weight loss effect of GLP-1 RA in adults with obesity and overweight without diabetes mellitus. We retrieved eligible randomized control trials that assessed the weight loss effect of GLP-1 RA in adults (≥18 years old) without type 1/type 2 diabetes up to September 30, 2021, using Pubmed and Embase. Of 36 clinical trials assessed for eligibility, 12 trials were included, with a combined total of 11,459 participants. Compared with control groups, a more significant weight loss was seen in GLP-1 RA groups with an overall mean difference of -7.1kg (95% CI -9.2 to -5.0) (I2 = 99%). The overall analysis results showed that GLP-1 RA improved glycemic control without increasing the risk of hypoglycemic events. Better control of blood pressure and plasma levels of LDL, HDL, and triglycerides was seen with GLP-1 RA treatment. Subgroup analysis showed greater treatment effect of semaglutide than liraglutide. Vomiting, nausea, dyspepsia, diarrhea, constipation, and abdominal pain were GLP-1 RA-associated common adverse effects.

MiR-155 activates the NLRP3 inflammasome by regulating the MEK/ERK/NF-κB pathway in carotid atherosclerotic plaques in ApoE-/- mice.

Atherosclerosis is an inflammatory disease. The NLRP3 inflammasome and miR-155 are significant components of inflammation and atherosclerosis. The aim of this research was to explore the possible mechanism by which miR-155 mediates the formation of carotid atherosclerotic plaques via the NLRP3 inflammasome. Fifty 6-week-old male ApoE-/- mice were randomly divided into 5 groups. They are the blank group, the negative control (NC) group, the miR-155 mimic group, the miR-155 inhibitor group, and the miR-155 mimic and ERK inhibitor group. The blood lipid levels were measured by the enzyme method Oil red O, HE, and immunohistochemical staining were used to observe the degree of carotid plaque formation. PCR was used to measure the expression of miR-155. The blood lipid levels were measured by the enzyme method. Western blotting was used to measure the expression of NLRP3 inflammasome-related proteins, interleukin-1β, interleukin-18, and MEK/ERK/NF-κB signaling pathway-related proteins. Compared with those of the NC group, the expression of miR-155 in the miR-155 mimic group increased significantly (P < 0.05), the degree of carotid plaque formation increased, the plasma levels of TC and LDL also increased significantly (P < 0.05); the expression levels of NLRP3 inflammasome-related proteins, interleukin-1β, interleukin-18, and MEK/ERK/NF-κB signaling pathway-related proteins were also significantly increased. Injection of ERK inhibitors into miR-155 mimic mice reduced the expression levels of p-NF-κB, NLRP3 inflammasome-related proteins, and inflammatory cytokines. In conclusion, miR-155 can promote the formation of atherosclerotic plaque in ApoE-/- mice, which may be achieved by regulating the MEK/ERK/NF-κB pathway to activate the NLRP3 inflammasome. HIGHLIGHTS: • In ApoE-/- mice, miR-155 promotes atherosclerotic plaque formation. • The NLRP3 inflammasome has an important role in the inflammatory process of atherosclerosis. • miR-155 activates the NLRP3 inflammasome by regulating the MEK/ERK/NF-κB pathway in carotid atherosclerotic plaques of ApoE-/- mice.

Bisphenol S exposure accelerates the progression of atherosclerosis in zebrafish embryo-larvae

Bisphenol S (BPS), widely utilized in manufacturing of daily necessities, is a toxicant with potential to induce atherosclerotic cardiovascular disease (ASCVD). However, the mode of action by which BPS exposure induces ASCVD remains unknown. Here, macrophages that were exposed to BPS in combination with oxidized low-density lipoprotein (oxLDL) exhibited enhanced formation of foam cells, a hallmark of ASCVD. Furthermore, zebrafish embryo-larvae were exposed to BPS (0, 1, 10 and 100 μg/L) for 15 days (d) and the characteristic symptoms of ASCVD including an inflammatory response, macrophage recruitment around blood vessels, and accumulation of oxLDL on vascular endothelium, were induced in 15-d larvae. After zebrafish were exposed to BPS for 45 d, BPS mobilized fatty acid metabolism and activated peroxisome proliferator-activated receptor signaling in larval liver, the hub of endogenous lipid metabolism, causing an increase in plasma LDL. Driven by high plasma LDL levels, the caudal artery of zebrafish larvae exhibited lipid accumulation and a thickened area with a large number of collagen fibers, accompanied by characteristic lesions, as well as hyperlipidemia, erythrocyte aggregation, thinner blood vessel walls and increased levels of leukocytes and thromboocytes in plasma. Our data demonstrate that BPS accelerates the progression of ASCVD using zebrafish embryo-larvae as a model.

Identification of the atherosclerosis phenotype in vivo by vascular duplex ultrasonography in ApoE-deficient dogs

Background and aimsThis study evaluated the atherosclerosis phenotype by vascular duplex ultrasonography (VDU) in ApoE-deficient dogs. MethodsA total of 108 beagle dogs were examined by VDU, which included 32 wild-type, 68 heterozygous (ApoE-/+) mutant and 8 homozygous (ApoE−/−) mutant dogs. According to age, wild-type and ApoE-/+ dogs were divided into two subgroups: young (6–15 months) and adult dogs (18–29 months). All homozygous dogs were young dogs. Dogs were feed with normal diet. The plasma lipid levels were tested. The diameter of the common carotid artery (CCA), internal carotid artery (ICA), external carotid artery (ECA), abdominal aorta and common iliac artery (CIA) and the intima-media thickness (IMT) of the CCA and abdominal aorta were measured by VDU. The artery sections of ApoE−/− and control dogs were analyzed by histological analysis. ResultsThe plasma triglycerides (2.5–3 fold), total cholesterol (4–5 fold) and LDL levels (35–40 fold) of ApoE−/− dogs were higher than those of the wild-type and ApoE-/+ dogs. Compared with the wild-type and young ApoE-/+ dogs, the IMT of CCA and aorta in ApoE−/− dogs were increased (p<0.05). The occurrence of atherosclerosis in ApoE−/− dogs was higher than that in ApoE-/+ dogs (50% vs. 10.3%, p=0.013) and the occurrence time was earlier. Histology confirmed that the aorta, carotid arteries and CIA had atherosclerotic lesions in ApoE−/− dogs. ConclusionsThe ApoE-deficient dogs were a reliable animal model of atherosclerosis. VDU is an optimal in vivo noninvasive method for evaluating atherosclerosis phenotypes in large animal models.

Methylmercury chronic exposure affects the expression of DNA single-strand break repair genes, induces oxidative stress, and chromosomal abnormalities in young dyslipidemic APOE knockout mice

Mercury (Hg) is one of the most toxic environmental pollutants, especially when methylated, forming methylmercury (MeHg). MeHg affects DNA repair, increases oxidative stress, and predisposes to cancer. MeHg neurotoxicity is well-known, but recently MeHg-associated cardiovascular effects were recognized. This study evaluated circulating lipids, oxidative stress, and genotoxicity after MeHg-chronic exposure (20 mg/L in drinking water) in C57BL/6J wild-type and APOE knockout (ko) mice, the latter, being spontaneously dyslipidemic. Experimental mice were assigned to four groups: non-intoxicated and MeHg-intoxicated wild-type mice and non-intoxicated and MeHg-intoxicated APOE ko mice. Plasma levels of triglycerides, total cholesterol (TC), HDL, and LDL were analyzed. Liver lipid peroxidation and splenic gene expression of xeroderma pigmentosum complementation groups A, C, D, and G (XPA, XPC, XPD, and XPG), X-ray repair cross-complementing protein 1 (XRCC1), and telomerase reverse transcriptase (TERT) were measured. Fur Hg levels confirmed chronic MeHg intoxication. MeHg exposure raises TC levels both in wild-type and APOE ko mice. HDL and LDL-cholesterol levels were increased only in the MeHg-challenged APOE ko mice. MeHg increased liver lipid peroxidation, regardless of the genetic background. Unintoxicated APOE ko mice showed higher expression of TERT than all other groups. APOE deficiency increases XPA expression, regardless of MeHg intoxication. Furthermore, MeHg-intoxicated mice had more cytogenetic abnormalities, effect which was independent of APOE deficiency. More studies are needed to dissect the interactions between circulating lipids, MeHg intoxication, and DNA-repair pathways even at young age, interactions that likely play critical roles in cell senescence and the risk for chronic disorders later in life.