Browsing by Subject "CHOLESTEROL"

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  • Lluch, Aina; Veiga, Sonia R.; Latorre, Jèssica; Moreno-Navarrete, José M.; Bonifaci, Núria; Nguyen, Van Dien; Zhou, You; Höring, Marcus; Liebisch, Gerhard; Olkkonen, Vesa M.; Llobet-Navas, David; Thomas, George; Rodríguez-Barrueco, Ruth; Fernández-Real, José M.; Kozma, Sara C.; Ortega, Francisco J. (2022)
    The ribosomal protein S6 kinase 1 (S6K1) is a relevant effector downstream of the mammalian target of rapamycin complex 1 (mTORC1), best known for its role in the control of lipid homeostasis. Consistent with this, mice lacking the S6k1 gene have a defect in their ability to induce the commitment of fat precursor cells to the adipogenic lineage, which contributes to a significant reduction of fat mass. Here, we assess the therapeutic blockage of S6K1 in diet-induced obese mice challenged with LY2584702 tosylate, a specific oral S6K1 inhibitor initially developed for the treatment of solid tumors. We show that diminished S6K1 activity hampers fat mass expansion and ameliorates dyslipidemia and hepatic steatosis, while modifying transcriptome-wide gene expression programs relevant for adipose and liver function. Accordingly, decreased mTORC1 signaling in fat (but increased in the liver) segregated with defective epithelial-mesenchymal transition and the impaired expression of Cd36 (coding for a fatty acid translocase) and Lgals1 (Galectin 1) in both tissues. All these factors combined align with reduced adipocyte size and improved lipidomic signatures in the liver, while hepatic steatosis and hypertriglyceridemia were improved in treatments lasting either 3 months or 6 weeks.
  • Leskinen, Heidi; Tringham, Maaria; Karjalainen, H.; Iso-Touru, T.; Hietaranta-Luoma, Hanna-Leena; Marnila, P.; Pihlava, J.-M.; Hurme, T.; Puolijoki, H.; Åkerman, K.; Mäkinen, Sari; Sandell, Mari; Vähäkangas, K.; Tahvonen, R.; Rokka, Susanna; Hopia, Anu (2022)
    Introduction: The APOE ε4 allele predisposes to high cholesterol and increases the risk for lifestyle-related diseases such as Alzheimer’s disease and cardiovascular diseases (CVDs). The aim of this study was to analyse interrelationships of APOE genotypes with lipid metabolism and lifestyle factors in middle-aged Finns among whom the CVD risk factors are common. Methods: Participants (n = 211) were analysed for APOE ε genotypes, physiological parameters, and health- and diet-related plasma markers. Lifestyle choices were determined by a questionnaire. Results: APOE genotypes ε3/ε4 and ε4/ε4 (ε4 group) represented 34.1% of the participants. Genotype ε3/ε3 (ε3 group) frequency was 54.5%. Carriers of ε2 (ε2 group; ε2/ε2, ε2/ε3 and ε2/ε4) represented 11.4%; 1.9% were of the genotype ε2/ε4. LDL and total cholesterol levels were lower (p < 0.05) in the ε2 carriers than in the ε3 or ε4 groups, while the ε3 and ε4 groups did not differ. Proportions of plasma saturated fatty acids (SFAs) were higher (p < 0.01), and omega-6 fatty acids lower (p = 0.01) in the ε2 carriers compared with the ε4 group. The ε2 carriers had a higher (p < 0.05) percentage of 22:4n-6 and 22:5n-6 and a lower (p < 0.05) percentage of 24:5n-3 and 24:6n-3 than individuals without the ε2 allele. Conclusions: The plasma fatty-acid profiles in the ε2 group were characterized by higher SFA and lower omega-6 fatty-acid proportions. Their lower cholesterol values indicated a lower risk for CVD compared with the ε4 group. A novel finding was that the ε2 carriers had different proportions of 22:4n-6, 22:5n-6, 24:5n-3, and 24:6n-3 than individuals without the ε2 allele. The significance of the differences in fatty-acid composition remains to be studied.
  • Slighoua, Meryem; Mahdi, Ismail; Amrati, Fatima ez-Zahra; Di Cristo, Francesca; Amaghnouje, Amal; Grafov, Andrey; Boucetta, Nabil; Bari, Amina; Bousta, Dalila (2021)
    Ethnopharmacological relevance: Since the dawn of time, medicinal and aromatic plants (AMPs) represent a precious heritage for humanity, especially in developing countries, who exploit their virtues in traditional pharmacopoeia to cope with health problems such as diabetes, kidney stones, ulcer, and digestive disorders. Petroselinum sativum Hoffm. belongs to Apiaceae family. It is traditionally used to treat arterial hypertension, diabetes, cardiac disease, renal disease, and recently reported as a plant endowed with a female anti-infertility effect. Aim of the study: This study aims to evaluate the in vivo effect of hydro-ethanolic extract and polyphenols of Petroselinum sativum Hoffm. on cholesterol, protein and estrogen levels, and characterize the chemical composition of polyphenolic fraction. In addition, acute toxicity and anti-inflammatory activity of tested extract was also investigated. Materials and methods: Chemical composition of polyphenolic fraction was determined using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). First, toxicological investigations including sub-acute toxicity were performed by measuring animals' weights daily for four weeks. Afterwards, histopathological examination of livers and kidneys, and serum assay of ASAT and ALAT were also checked. Next, the acute in vivo anti-inflammatory study of the hydro-ethanolic extract and polyphenols of Petroselinum sativum Hoffm. versus Indomethacin was conducted. Furthermore, we evaluated the estrogenic effect of its hydroethanolic extract and the polyphenolic fraction following biochemical assays for the determination of proteins, cholesterol and estrogen levels. Results: The results revealed the presence of some phenolic compounds mainly ferulic acid, gallic acid and quercetin. Petroselinum sativum Hoffm. extracts also showed no evidence of hepatotoxicity nor nephrotoxicity, with remarkable anti-inflammatory activity, as well as a significant estrogenic effect compared to negative control. Conclusion: This study provides a scope of the potential use of Petroselinum sativum Hoffm. extracts in counteracting female infertility issues.
  • Vojinovic, Dina; Kalaoja, Marita; Trompet, Stella; Fischer, Krista; Shipley, Martin J.; Li, Shuo; Havulinna, Aki S.; Perola, Markus; Salomaa, Veikko; Yang, Qiong; Sattar, Naveed; Jousilahti, Pekka; Amin, Najaf; Satizabal, Claudia L.; Taba, Nele; Sabayan, Behnam; Vasan, Ramachandran S.; Ikram, M. Arfan; Stott, David J.; Ala-Korpela, Mika; Jukema, J. Wouter; Seshadri, Sudha; Kettunen, Johannes; Kivimaki, Mika; Esko, Tonu; van Duijn, Cornelia M. (2021)
    Objective To conduct a comprehensive analysis of circulating metabolites and incident stroke in large prospective population-based settings. Methods We investigated the association of metabolites with risk of stroke in 7 prospective cohort studies including 1,791 incident stroke events among 38,797 participants in whom circulating metabolites were measured by nuclear magnetic resonance technology. The relationship between metabolites and stroke was assessed with Cox proportional hazards regression models. The analyses were performed considering all incident stroke events and ischemic and hemorrhagic events separately. Results The analyses revealed 10 significant metabolite associations. Amino acid histidine (hazard ratio [HR] per SD 0.90, 95% confidence interval [CI] 0.85, 0.94; p = 4.45 x 10-5), glycolysis-related metabolite pyruvate (HR per SD 1.09, 95% CI 1.04, 1.14; p = 7.45 x 10-4), acute-phase reaction marker glycoprotein acetyls (HR per SD 1.09, 95% CI 1.03, 1.15; p = 1.27 x 10-3), cholesterol in high-density lipoprotein (HDL) 2, and several other lipoprotein particles were associated with risk of stroke. When focused on incident ischemic stroke, a significant association was observed with phenylalanine (HR per SD 1.12, 95% CI 1.05, 1.19; p = 4.13 x 10-4) and total and free cholesterol in large HDL particles. Conclusions We found association of amino acids, glycolysis-related metabolites, acute-phase reaction markers, and several lipoprotein subfractions with the risk of stroke. These findings support the potential of metabolomics to provide new insights into the metabolic changes preceding stroke.
  • Poojari, Chetan; Wilkosz, Natalia; Lira, Rafael B.; Dimova, Rumiana; Jurkiewicz, Piotr; Petka, Rafal; Kepczynski, Mariusz; Rog, Tomasz (2019)
    1,6-Diphenyl-1,3,5-hexatriene (DPH) is one of the most commonly used fluorescent probes to study dynamical and structural properties of lipid bilayers and cellular membranes via measuring steady-state or time-resolved fluorescence anisotropy. In this study, we present a limitation in the use of DPH to predict the order of lipid acyl chains when the lipid bilayer is doped with itraconazole (ITZ), an antifungal drug. Our steady-state fluorescence anisotropy measurements showed a significant decrease in fluorescence anisotropy of DPH embedded in the ITZ-containing membrane, suggesting a substantial increase in membrane fluidity, which indirectly indicates a decrease in the order of the hydrocarbon chains. This result or its interpretation is in disagreement with the fluorescence recovery after photobleaching measurements and molecular dynamics (MD) simulation data. The results of these experiments and calculations indicate an increase in the hydrocarbon chain order. The MD simulations of the bilayer containing both ITZ and DPH provide explanations for these observations. Apparently, in the presence of the drug, the DPH molecules are pushed deeper into the hydrophobic membrane core below the lipid double bonds, and the probe predominately adopts the orientation of the ITZ molecules that is parallel to the membrane surface, instead of orienting parallel to the lipid acyl chains. For this reason, DPH anisotropy provides information related to the less ordered central region of the membrane rather than reporting the properties of the upper segments of the lipid acyl chains.
  • Liang, Yajun; Ngandu, Tiia; Laatikainen, Tiina; Soininen, Hilkka; Tuomilehto, Jaakko; Kivipelto, Miia; Qiu, Chengxuan (2020)
    Background Very few studies have explored the patterns of cardiovascular health (CVH) metrics in midlife and late life in relation to risk of dementia. We examined the associations of composite CVH metrics from midlife to late life with risk of incident dementia. Methods and findings This cohort study included 1,449 participants from the Finnish Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study, who were followed from midlife (baseline from1972 to 1987; mean age 50.4 years; 62.1% female) to late life (1998), and then 744 dementia-free survivors were followed further into late life (2005 to 2008). We defined and scored global CVH metrics based on 6 of the 7 components (i.e., smoking, physical activity, and body mass index [BMI] as behavioral CVH metrics; fasting plasma glucose, total cholesterol, and blood pressure as biological CVH metrics) following the modified American Heart Association (AHA)'s recommendations. Then, the composite global, behavioral, and biological CVH metrics were categorized into poor, intermediate, and ideal levels. Dementia was diagnosed following the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. Data were analyzed with Cox proportional hazards and the Fine and Gray competing risk regression models. During the follow-up examinations, dementia was diagnosed in 61 persons in 1998 and additional 47 persons in 2005 to 2008. The fully adjusted hazard ratio (HR) of dementia was 0.71 (95% confidence interval [CI]: 0.43, 1.16; p = 0.174) and 0.52 (0.29, 0.93; p = 0.027) for midlife intermediate and ideal levels (versus poor level) of global CVH metrics, respectively; the corresponding figures for late-life global CVH metrics were 0.60 (0.22, 1.69; p = 0.338) and 0.91 (0.34, 2.41; p = 0.850). Compared with poor global CVH metrics in both midlife and late life, the fully adjusted HR of dementia was 0.25 (95% CI: 0.08, 0.86; p = 0.028) for people with intermediate global CVH metrics in both midlife and late life and 0.14 (0.02, 0.76; p = 0.024) for those with midlife ideal and late-life intermediate global CVH metrics. Having an intermediate or ideal level of behavioral CVH in both midlife and late life (versus poor level in both midlife and late life) was significantly associated with a lower dementia risk (HR range: 0.03 to 0.26; p <0.05), whereas people with midlife intermediate and late-life ideal biological CVH metrics had a significantly increased risk of dementia (p = 0.031). Major limitations of this study include the lack of data on diet and midlife plasma glucose, high rate of attrition, as well as the limited power for certain subgroup analyses. Conclusions In this study, we observed that having the ideal CVH metrics, and ideal behavioral CVH metrics in particular, from midlife onwards is associated with a reduced risk of dementia as compared with people having poor CVH metrics. Maintaining life-long health behaviors may be crucial to reduce late-life risk of dementia. Author summary Why was this study done? Dementia is a global public health problem, but there is currently no cure or a disease-modifying therapy for dementia. Simulation studies suggested that interventions targeting modifiable risk factors (e.g., cardiovascular factors) could prevent up to one-third of dementia cases. A better understanding of the life-long cardiovascular health (CVH) metrics and risk of dementia may facilitate the development of optimal intervention strategies. What did the researchers do and find? We examined the associations of CVH metrics in midlife and late life with risk of incident dementia in a population-based cohort of 1,449 participants in Finland followed for around 30 years. Compared with poor CVH metrics, the ideal global and behavioral CVH metrics in midlife were associated with a reduced risk of dementia, whereas the ideal biological CVH metrics in late life appeared to be associated with an increased risk of dementia. Having an intermediate or ideal level of behavioral CVH metrics from midlife onwards was associated with a late-life reduced risk of dementia. What do these findings mean? The association of ideal global CVH metrics with a reduced dementia risk disappeared from midlife to old age, driven largely by the age-varying association between biological CVH metrics and risk of dementia. Maintaining a life-long optimal level of CVH metrics, especially behavioral health metrics, may reduce late-life risk of dementia. The association of late-life ideal biological CVH metrics with an increased risk of dementia may largely reflect the potential of reverse causality.
  • Hakala, JO; Pahkala, K; Juonala, M; Salo, P; Kahonen, M; Hutri-Kahonen, N; Lehtimaki, T; Laitinen, TP; Jokinen, E; Taittonen, L; Tossavainen, P; Viikari, JSA; Raitakari, OT; Rovio, SP (2021)
    Background: Cardiovascular risk factors, such as high blood pressure, adverse serum lipids, and elevated body mass index in midlife, may harm cognitive performance. It is important to note that longitudinal accumulation of cardiovascular risk factors since childhood may be associated with cognitive performance already since childhood, but the previous evidence is scarce. We studied the associations of cardiovascular risk factors from childhood to midlife, their accumulation, and midlife cognitive performance. Methods: From 1980, a population-based cohort of 3596 children (3-18 years of age) have been repeatedly followed up for 31 years. Blood pressure, serum lipids, and body mass index were assessed in all follow-ups. Cardiovascular risk factor trajectories from childhood to midlife were identified using latent class growth mixture modeling. Cognitive testing was performed in 2026 participants 34 to 49 years of age using a computerized test. The associations of the cardiovascular risk factor trajectories and cognitive performance were studied for individual cardiovascular risk factors and cardiovascular risk factor accumulation. Results: Consistently high systolic blood pressure (beta=-0.262 SD [95% CI, -0.520 to -0.005]) and serum total cholesterol (beta=-0.214 SD [95% CI, -0.365 to -0.064]) were associated with worse midlife episodic memory and associative learning compared with consistently low values. Obesity since childhood was associated with worse visual processing and sustained attention (beta=-0.407 SD [95% CI, -0.708 to -0.105]) compared with normal weight. An inverse association was observed for the cardiovascular risk factor accumulation with episodic memory and associative learning (P for trend=0.008; 3 cardiovascular risk factors: beta=-0.390 SD [95% CI, -0.691 to -0.088]), with visual processing and sustained attention (P for trend Conclusions: Longitudinal elevated systolic blood pressure, high serum total cholesterol, and obesity from childhood to midlife were inversely associated with midlife cognitive performance. It is important to note that the higher the number of cardiovascular risk factors, the worse was the observed cognitive performance. Therefore, launching preventive strategies against cardiovascular risk factors beginning from childhood might benefit primordial promotion of cognitive health in adulthood.
  • Rovio, Suvi P.; Pahkala, Katja; Nevalainen, Jaakko; Juonala, Markus; Salo, Pia; Kahonen, Mika; Hutri-Kahonen, Nina; Lehtimaki, Terho; Jokinen, Eero; Laitinen, Tomi; Taittonen, Leena; Tossavainen, Paivi; Viikari, Jorma S. A.; Rinne, Juha O.; Raitakari, Olli T. (2017)
    BACKGROUND In adults, high blood pressure (BP), adverse serum lipids, and smoking associate with cognitive deficits. The effects of these risk factors from childhood on midlife cognitive performance are unknown. OBJECTIVES This study sought to investigate the associations between childhood/adolescence cardiovascular risk factors and midlife cognitive performance. METHODS From 1980, a population-based cohort of 3,596 children (baseline age: 3 to 18 years) have been followed for 31 years in 3- to 9-year intervals. BP, serum lipids, body mass index, and smoking were assessed in all follow-ups. Cumulative exposure as the area under the curve for each risk factor was determined in childhood (6 to 12 years), adolescence (12 to 18 years), and young adulthood (18 to 24 years). In 2011, cognitive testing was performed in 2,026 participants aged 34 to 49 years. RESULTS High systolic BP, elevated serum total-cholesterol, and smoking from childhood were independently associated with worse midlife cognitive performance, especially memory and learning. The number of early life risk factors, including high levels (extreme 75th percentile for cumulative risk exposure between ages 6 and 24 years) of systolic BP, total-cholesterol, and smoking associated inversely with midlife visual and episodic memory and visuospatial associative learning (-0.140 standard deviations per risk factor, p <0.0001) and remained significant after adjustment for contemporaneous risk factors. Individuals with all risk factors within recommended levels between ages 6 and 24 years performed 0.29 standard deviations better (p = 0.006) on this cognitive domain than those exceeding all risk factor guidelines at least twice. This difference corresponds to the effect of 6 years aging on this cognitive domain. CONCLUSIONS Cumulative burden of cardiovascular risk factors from childhood/adolescence associate with worse midlife cognitive performance independent of adulthood exposure. (C) 2017 by the American College of Cardiology Foundation.
  • Pham, Dan Duc; Bruelle, Celine; Do, Hai Thi; Pajanoja, Ceren; Jin, Congyu; Olkkonen, Vesa M.; Eriksson-Rosenberg, Ove; Jauhiainen, Matti; Lalowski, Maciej; Lindholm, Dan (2019)
    Lipid-induced toxicity is part of several human diseases, but the mechanisms involved are not fully understood. Fatty liver is characterized by the expression of different growth and tissue factors. The neurotrophin, nerve growth factor (NGF) and its pro-form, pro-NGF, are present in fatty liver together with p75 neurotrophin receptor (p75NTR). Stimulation of human Huh7 hepatocyte cells with NGF and pro-NGF induced Sterol-regulator-element-binding protein-2 (SREBP2) activation and increased Low-Density Lipoprotein Receptor (LDLR) expression. We observed that phosphorylation of caspase-2 by p38 MAPK was essential for this regulation involving a caspase-3-mediated cleavage of SREBP2. RNA sequencing showed that several genes involved in lipid metabolism were altered in p75NTR-deficient mouse liver. The same lipogenic genes were downregulated in p75NTR gene-engineered human Huh7 cells and reciprocally upregulated by stimulation of p75NTRs. In the knock-out mice the serum cholesterol and triglyceride levels were reduced, suggesting a physiological role of p75NTRs in whole-body lipid metabolism. Taken together, this study shows that p75NTR signaling influences a network of genes involved in lipid metabolism in liver and hepatocyte cells. Modulation of p75NTR signaling may be a target to consider in various metabolic disorders accompanied by increased lipid accumulation.
  • Holm, Matilda; Saraswat, Mayank; Joenväärä, Sakari; Ristimäki, Ari; Haglund, Caj; Renkonen, Risto (2018)
    Over 1.4 million people are diagnosed with colorectal cancer (CRC) each year, making it the third most common cancer in the world. Increased screening and therapeutic modalities including improved combination treatments have reduced CRC mortality, although incidence and mortality rates are still increasing in some areas. Serum-based biomarkers are mainly used for follow-up of cancer, and are ideal due to the ease and minimally invasive nature of sample collection. Unfortunately, CEA and other serum markers have too low sensitivity for screening and preoperative diagnostic purposes. Increasing interest is focused on the possible use of biomarkers for predicting treatment response and prognosis in cancer. In this study, we have performed mass spectrometry analysis (UPLC-UDMSE) of serum samples from 19 CRC patients. Increased levels of C-reactive protein (CRP), which occur during local inflammation and the presence of a systemic inflammatory response, have been linked to poor prognosis in CRC patients. We chose to analyze samples according to CRP values by dividing them into the categories CRP 30, and, separately, according to short and long 5-year survival. The aim was to discover differentially expressed proteins associated with poor prognosis and shorter survival. We quantified 256 proteins and performed detailed statistical analyses and pathway analysis. We discovered multiple proteins that are up- or downregulated in patients with CRP >30 as compared to CRP
  • Kulig, Waldemar; Korolainen, Hanna; Zatorska, Maria; Kwolek, Urszula; Wydro, Pawel; Kepczynski, Mariusz; Rog, Tomasz (2019)
    Phosphatidic acids (PAs) have many biological functions in biomembranes, e.g., they are involved in the proliferation, differentiation, and transformation of cells. Despite decades of research, the molecular understanding of how PAs affect the properties of biomembranes remains elusive. In this study, we explored the properties of lipid bilayers and monolayers composed of PAs and phosphatidylcholines (PCs) with various acyl chains. For this purpose, the Langmuir monolayer technique and atomistic molecular dynamics (MD) simulations were used to study the miscibility of PA and PC lipids and the molecular organization of mixed bilayers. The monolayer experiments demonstrated that the miscibility of membrane components strongly depends on the structure of the hydrocarbon chains and thus on the overall lipid shape. Interactions between PA and PC molecules vary from repulsive, for systems containing lipids with saturated and unsaturated acyl tails (strongly positive values of the excess free energy of mixing), to attractive, for systems in which all lipid tails are saturated (negative values of the excess free energy of mixing). The MD simulations provided atomistic insight into polar interactions (formation of hydrogen bonds and charge pairs) in PC-PA systems. H-bonding between PA monoanions and PCs in mixed bilayers is infrequent, and the lipid molecules interact mainly via electrostatic interactions. However, the number of charge pairs significantly decreases with the number of unsaturated lipid chains in the PA-PC system. The PA dianions weakly interact with the zwitterionic lipids, but their headgroups are more hydrated as compared to the monoanionic form. The acyl chains in all PC-PA bilayers are more ordered compared to single-component PC systems. In addition, depending on the combination of lipids, we observed a deeper location of the PA phosphate groups compared to the PC phosphate groups, which can alter the presentation of PAs for the peripheral membrane proteins, affecting their accessibility for binding.
  • Stepien, Piotr; Augustyn, Bozena; Poojari, Chetan; Galan, Wojciech; Polit, Agnieszka; Vattulainen, Ilpo; Wisnieska-Becker, Anna; Rog, Tomasz (2020)
    Lipid nanodiscs are macromolecular assemblies, where a scaffold protein is wrapped around a nanosized disc of a lipid bilayer, thus protecting the hydrocarbon chains at the disc edges from unfavorable interactions with water. These nanostructures have numerous applications in, e.g., nanotechnology and pharmaceutics, and in investigations of membrane proteins. Here, we present results based on atomistic molecular dynamics simulations combined with electron paramagnetic spectroscopy measurements on the structure and dynamics of lipids in single-component nanodiscs. Our data highlight the existence of three distinctly different lipid fractions: central lipids residing in the center of a nanodisc, boundary lipids in direct contact with a scaffold protein, and intermediate lipids between these two regions. The central lipids are highly ordered and characterized by slow diffusion. In this part of the nanodisc, the membrane is the thickest and characterized by a gel-like or liquid-ordered phase, having features common to cholesterol-rich membranes. The boundary lipids in direct contact with the scaffold protein turned out to be less ordered and characterized by faster diffusion, and they remained in the liquid-disordered phase even at temperatures that were somewhat below the main phase transition temperature (Tm). The enthalpies associated with the central-boundary and central-intermediate transitions were similar to those observed for lipids going through the main phase transition. Overall, the study reveals lipid nanodiscs to be characterized by a complex internal structure, which is expected to influence membrane proteins placed in nanodiscs.
  • Latorre, Jèssica; Ortega, Francisco J.; Liñares-Pose, Laura; Moreno-Navarrete, José M.; Lluch, Aina; Comas, Ferran; Oliveras-Cañellas, Núria; Ricart, Wifredo; Höring, Marcus; Zhou, You; Liebisch, Gerhard; Nidhina Haridas, P.A.; Olkkonen, Vesa M.; López, Miguel; Fernández-Real, José M. (2020)
    Background: While the impact of metformin in hepatocytes leads to fatty acid (FA) oxidation and decreased lipogenesis, hepatic microRNAs (miRNAs) have been associated with fat overload and impaired metabolism, contributing to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Methods: We investigated the expression of hundreds of miRNAs in primary hepatocytes challenged by compounds modulating steatosis, palmitic acid and compound C (as inducers), and metformin (as an inhibitor). Then, additional hepatocyte and rodent models were evaluated, together with transient mimic miRNAs transfection, lipid droplet staining, thin-layer chromatography, quantitative lipidomes, and mitochondrial activity, while human samples outlined the translational significance of this work. Findings: Our results show that treatments triggering fat accumulation and AMPK disruption may compromise the biosynthesis of hepatic miRNAs, while the knockdown of the miRNA-processing enzyme DICER in human hepatocytes exhibited increased lipid deposition. In this context, the ectopic recovery of miR-30b and miR-30c led to significant changes in genes related to FA metabolism, consistent reduction of ceramides, higher mitochondrial activity, and enabled b-oxidation, redirecting FA metabolism fromenergy storage to expenditure. Interpretation: Current findings unravel the biosynthesis of hepatic miR-30b and miR-30c in tackling inadequate FA accumulation, offering a potential avenue for the treatment of NAFLD. Funding: Instituto de Salud Carlos III (ISCIII), Govern de la Generalitat (PERIS2016), Associacio Catalana de Diabetis (ACD), Sociedad Espanola de Diabetes (SED), Fondo Europeo de Desarrollo Regional (FEDER), Xunta de Galicia, Ministerio de Economia y Competitividad (MINECO), "La Caixa" Foundation, and CIBER de la Fisiopatologia de la Obesidad y Nutricion (CIBEROBN). (c) 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)
  • Key, Timothy J.; Appleby, Paul N.; Bradbury, Kathryn E.; Sweeting, Michael; Wood, Angela; Johansson, Ingegerd; Kuehn, Tilman; Steur, Marinka; Weiderpass, Elisabete; Wennberg, Maria; Wuertz, Anne Mette Lund; Agudo, Antonio; Andersson, Jonas; Arriola, Larraitz; Boeing, Heiner; Boer, Jolanda M. A.; Bonnet, Fabrice; Boutron-Ruault, Marie-Christine; Cross, Amanda J.; Ericson, Ulrika; Fagherazzi, Guy; Ferrari, Pietro; Gunter, Marc; Huerta, Jose Maria; Katzke, Verena; Khaw, Kay-Tee; Krogh, Vittorio; La Vecchia, Carlo; Matullo, Giuseppe; Moreno-Iribas, Conchi; Naska, Androniki; Nilsson, Lena Maria; Olsen, Anja; Overvad, Kim; Palli, Domenico; Panico, Salvatore; Molina-Portillo, Elena; Quiros, J. Ramon; Skeie, Guri; Sluijs, Ivonne; Sonestedt, Emily; Stepien, Magdalena; Tjonneland, Anne; Trichopoulou, Antonia; Tumino, Rosario; Tzoulaki, Ioanna; van der Schouw, Yvonne T.; Verschuren, W. M. Monique; di Angelantonio, Emanuele; Langenberg, Claudia; Forouhi, Nita; Wareham, Nick; Butterworth, Adam; Riboli, Elio; Danesh, John (2019)
    Background: There is uncertainty about the relevance of animal foods to the pathogenesis of ischemic heart disease (IHD). We examined meat, fish, dairy products, and eggs and risk for IHD in the pan-European EPIC cohort (European Prospective Investigation Into Cancer and Nutrition). Methods: In this prospective study of 409 885 men and women in 9 European countries, diet was assessed with validated questionnaires and calibrated with 24-hour recalls. Lipids and blood pressure were measured in a subsample. During a mean of 12.6 years of follow-up, 7198 participants had a myocardial infarction or died of IHD. The relationships of animal foods with risk were examined with Cox regression with adjustment for other animal foods and relevant covariates. Results: The hazard ratio (HR) for IHD was 1.19 (95% CI, 1.06-1.33) for a 100-g/d increment in intake of red and processed meat, and this remained significant after exclusion of the first 4 years of follow-up (HR, 1.25 [95% CI, 1.09-1.42]). Risk was inversely associated with intakes of yogurt (HR, 0.93 [95% CI, 0.89-0.98] per 100-g/d increment), cheese (HR, 0.92 [95% CI, 0.86-0.98] per 30-g/d increment), and eggs (HR, 0.93 [95% CI, 0.88-0.99] per 20-g/d increment); the associations with yogurt and eggs were attenuated and nonsignificant after exclusion of the first 4 years of follow-up. Risk was not significantly associated with intakes of poultry, fish, or milk. In analyses modeling dietary substitutions, replacement of 100 kcal/d from red and processed meat with 100 kcal/d from fatty fish, yogurt, cheese, or eggs was associated with approximate to 20% lower risk of IHD. Consumption of red and processed meat was positively associated with serum non-high-density lipoprotein cholesterol concentration and systolic blood pressure, and consumption of cheese was inversely associated with serum non-high-density lipoprotein cholesterol. Conclusions: Risk for IHD was positively associated with consumption of red and processed meat and inversely associated with consumption of yogurt, cheese, and eggs, although the associations with yogurt and eggs may be influenced by reverse causation bias. It is not clear whether the associations with red and processed meat and cheese reflect causality, but they were consistent with the associations of these foods with plasma non-high-density lipoprotein cholesterol and for red and processed meat with systolic blood pressure, which could mediate such effects.
  • Ohukainen, Pauli; Kuusisto, Sanna; Kettunen, Johannes; Perola, Markus; Järvelin, Marjo-Riitta; Makinen, Ville-Petteri; Ala-Korpela, Mika (2020)
    Background and aims: Population subgrouping has been suggested as means to improve coronary heart disease (CHD) risk assessment. We explored here how unsupervised data-driven metabolic subgrouping, based on comprehensive lipoprotein subclass data, would work in large-scale population cohorts. Methods: We applied a self-organizing map (SOM) artificial intelligence methodology to define subgroups based on detailed lipoprotein profiles in a population-based cohort (n = 5789) and utilised the trained SOM in an independent cohort (n = 7607). We identified four SOM-based subgroups of individuals with distinct lipoprotein profiles and CHD risk and compared those to univariate subgrouping by apolipoprotein B quartiles. Results: The SOM-based subgroup with highest concentrations for non-HDL measures had the highest, and the subgroup with lowest concentrations, the lowest risk for CHD. However, apolipoprotein B quartiles produced better resolution of risk than the SOM-based subgroups and also striking dose-response behaviour. Conclusions: These results suggest that the majority of lipoprotein-mediated CHD risk is explained by apolipoprotein B-containing lipoprotein particles. Therefore, even advanced multivariate subgrouping, with comprehensive data on lipoprotein metabolism, may not advance CHD risk assessment
  • NHLBI TOPMED Lipids Working Grp (2018)
    Lipoprotein(a), Lp(a), is a modified low- density lipoprotein particle that contains apolipoprotein( a), encoded by LPA, and is a highly heritable, causal risk factor for cardiovascular diseases that varies in concentrations across ancestries. Here, we use deep-coverage whole genome sequencing in 8392 individuals of European and African ancestry to discover and interpret both single-nucleotide variants and copy number (CN) variation associated with Lp(a). We observe that genetic determinants between Europeans and Africans have several unique determinants. The common variant rs12740374 associated with Lp(a) cholesterol is an eQTL for SORT1 and independent of LDL cholesterol. Observed associations of aggregates of rare non-coding variants are largely explained by LPA structural variation, namely the LPA kringle IV 2 (KIV2)-CN. Finally, we find that LPA risk genotypes confer greater relative risk for incident atherosclerotic cardiovascular diseases compared to directly measured Lp(a), and are significantly associated with measures of subclinical atherosclerosis in African Americans.
  • Karhu, Lasse; Magarkar, Aniket; Bunker, Alex; Xhaard, Henri (2019)
    We assess the stability of two previously suggested binding modes for the neuropeptide orexin-A in the OX2 receptor through extensive molecular dynamics simulations. As the activation determinants of the receptor remain unknown, we simulated an unliganded receptor and two small-molecular ligands, the antagonist suvorexant and the agonist Nag26 for comparison. Each system was simulated in pure POPC membrane as well as in the 25% cholesterol–POPC membrane. In total, we carried out 36 μs of simulations. Through this set of simulations, we report a stable binding mode for the C-terminus of orexin-A. In addition, we suggest interactions that would promote orexin receptor activation, as well as others that would stabilize the inactive state.
  • Kaurola, Petri; Sharma, Vivek; Vonk, Amanda; Vattulainen, Ilpo; Rog, Tomasz (2016)
    Quinone and its analogues (Q) constitute an important class of compounds that perform key electron transfer reactions in oxidative- and photo-phosphorylation. In the inner membrane of mitochondria, ubiquinone molecules undergo continuous redox transitions enabling electron transfer between the respiratory complexes. In such a dynamic system undergoing continuous turnover for ATP synthesis, an uninterrupted supply of substrate molecules is absolutely necessary. In the current work, we have performed atomistic molecular dynamics simulations and free energy calculations to assess the structure, dynamics, and localization of quinone and its analogues in a lipid bilayer, whose composition mimics the one in the inner mitochondrial membrane. The results show that there is a strong tendency of both quinone and quinol molecules to localize in the vicinity of the lipids' acyl groups, right under the lipid head group region. Additionally, we observe a second location in the middle of the bilayer where quinone molecules tend to stabilize. Translocation of quinone through a lipid bilayer is very fast and occurs in 10-100 ns time scale, whereas the translocation of quinol is at least an order of magnitude slower. We suggest that this has important mechanistic implications given that the localization of Q ensures maximal occupancy of the Q-binding sites or Q-entry points in electron transport chain complexes, thereby maintaining an optimal turnover rate for ATP synthesis. (C) 2016 Elsevier B.V. All rights reserved.