Serum, liver and bile sitosterol and sitostanol in obese patients with and without NAFLD

Background and aims: Non-alcoholic fatty liver disease (NAFLD) associates with low levels of serum plant sterols in cross-sectional studies. In addition, it has been suggested that the hepatic sterol transport mechanisms are altered in NAFLD. Therefore, we investigated the association between serum, liver and bile plant sterols and sitostanol with NAFLD. Methods: Out of the 138 individuals (age: 46.3 +/- 8.9, body mass index: 43.3 +/- 6.9 kg/m(2), 28% men and 72% women), 44 could be histologically categorized to have normal liver, and 94 to have NAFLD. Within the NAFLD group, 28 had simple steatosis and 27 had non-alcoholic steatohepatitis. Plant sterols and sitostanol were measured from serum (n = 138), liver (n = 38), and bile (n = 41). The mRNA expression of genes regulating liver sterol metabolism and inflammation was measured (n = 102). Results: Liver and bile sitostanol ratios to cholesterol were higher in those with NAFLD compared to those with histologically normal liver (all P 0.407, P <0.01 for both). In contrast, liver sitosterol to cholesterol ratio correlated negatively with steatosis (r(s) = -0.392, P = 0.015) and lobular inflammation (r(s) = -0.395, P = 0.014). Transcriptomics analysis revealed suggestive correlations between serum plant sterol levels and mRNA expression. Conclusion: Our study showed that liver and bile sitostanol ratios to cholesterol associated positively and liver sitosterol ratio to cholesterol associated negatively with liver steatosis and inflammation in obese individuals with NAFLD..Peer reviewe

Indole-3-propionic acid, a gut-derived tryptophan metabolite, associates with hepatic fibrosis

Background and Aims: Gut microbiota-derived metabolites play a vital role in maintenance of human health and progression of disorders, including obesity and type 2 diabetes (T2D). Indole-3-propionic acid (IPA), a gut-derived tryptophan metabolite, has been recently shown to be lower in individuals with obesity and T2D. IPA’s beneficial effect on liver health has been also explored in rodent and cell models. In this study, we investigated the association of IPA with human liver histology and transcriptomics, and the potential of IPA to reduce hepatic stellate cell activation in vitro. Methods: A total of 233 subjects (72% women; age 48.3 ± 9.3 years; BMI 43.1 ± 5.4 kg/m2) undergoing bariatric surgery with detailed liver histology were included. Circulating IPA levels were measured using LC-MS and liver transcriptomics with total RNA-sequencing. LX-2 cells were used to study hepatoprotective effect of IPA in cells activated by TGF-β1. Results: Circulating IPA levels were found to be lower in individuals with liver fibrosis compared to those without fibrosis (p = 0.039 for all participants; p = 0.013 for 153 individuals without T2D). Accordingly, levels of circulating IPA associated with expression of 278 liver transcripts (p p Conclusion: The association of circulating IPA with liver fibrosis and the ability of IPA to reduce activation of LX-2 cells suggests that IPA may have a therapeutic potential. Further molecular studies are needed to investigate the mechanisms how IPA can ameliorate hepatic fibrosis.</p

Differential Mitochondrial Gene Expression in Adipose Tissue Following Weight Loss Induced by Diet or Bariatric Surgery

Context: Mitochondria are essential for cellular energy homeostasis, yet their role in subcutaneous adipose tissue (SAT) during different types of weight-loss interventions remains unknown. Objective: To investigate how SAT mitochondria change following diet-induced and bariatric surgery-induced weight-loss interventions in 4 independent weight-loss studies. Methods: The DiOGenes study is a European multicenter dietary intervention with an 8-week low caloric diet (LCD; 800 kcal/d; n = 261) and 6-month weight-maintenance (n = 121) period. The Kuopio Obesity Surgery study (KOBS) is a Roux-en-Y gastric bypass (RYGB) surgery study (n = 172) with a 1-year follow-up. We associated weight-loss percentage with global and 2210 mitochondria-related RNA transcripts in linear regression analysis adjusted for age and sex. We repeated these analyses in 2 studies. The Finnish CRYO study has a 6-week LCD (800-1000 kcal/d; n = 19) and a 10.5-month follow-up. The Swedish DEOSH study is a RYGB surgery study with a 2-year (n = 49) and 5-year (n = 37) follow-up. Results: Diet-induced weight loss led to a significant transcriptional downregulation of oxidative phosphorylation (DiOGenes; ingenuity pathway analysis [IPA] z-scores: -8.7 following LCD, -4.4 following weight maintenance; CRYO: IPA z-score: -5.6, all P < 0.001), while upregulation followed surgery-induced weight loss (KOBS: IPA z-score: 1.8, P < 0.001; in DEOSH: IPA z-scores: 4.0 following 2 years, 0.0 following 5 years). We confirmed an upregulated oxidative phosphorylation at the proteomics level following surgery (IPA z-score: 3.2, P < 0.001). Conclusions: Differentially regulated SAT mitochondria-related gene expressions suggest qualitative alterations between weight-loss interventions, providing insights into the potential molecular mechanistic targets for weight-loss success.Peer reviewe

Differential Mitochondrial Gene Expression in Adipose Tissue Following Weight Loss Induced by Diet or Bariatric Surgery

ContextMitochondria are essential for cellular energy homeostasis, yet their role in subcutaneous adipose tissue (SAT) during different types of weight-loss interventions remains unknown.ObjectiveTo investigate how SAT mitochondria change following diet-induced and bariatric surgery–induced weight-loss interventions in 4 independent weight-loss studies.MethodsThe DiOGenes study is a European multicenter dietary intervention with an 8-week low caloric diet (LCD; 800 kcal/d; n = 261) and 6-month weight-maintenance (n = 121) period. The Kuopio Obesity Surgery study (KOBS) is a Roux-en-Y gastric bypass (RYGB) surgery study (n = 172) with a 1-year follow-up. We associated weight-loss percentage with global and 2210 mitochondria-related RNA transcripts in linear regression analysis adjusted for age and sex. We repeated these analyses in 2 studies. The Finnish CRYO study has a 6-week LCD (800-1000 kcal/d; n = 19) and a 10.5-month follow-up. The Swedish DEOSH study is a RYGB surgery study with a 2-year (n = 49) and 5-year (n = 37) follow-up.ResultsDiet-induced weight loss led to a significant transcriptional downregulation of oxidative phosphorylation (DiOGenes; ingenuity pathway analysis [IPA] z-scores: −8.7 following LCD, −4.4 following weight maintenance; CRYO: IPA z-score: −5.6, all P ConclusionsDifferentially regulated SAT mitochondria-related gene expressions suggest qualitative alterations between weight-loss interventions, providing insights into the potential molecular mechanistic targets for weight-loss success.</p

Orientoidut vasta-aine -biointerfaasit nanofibrilloiduilla selluloosamateriaaleilla

Utilization of cellulose based materials in immunodiagnostic applications have recently gained increased interest. The literature part of this work reviews the basic structure of cellulosic fibers and some of the preparation methods, properties and functionalization techniques for nanofibrillated cellulose (NFC) and NFC films as well as some recent developments in diagnostic applications of cellulose based materials. In the experimental part a potential cellulose based support material for immunodiagnostic applications was developed by combining paper and an NFC film to a layer-structured material. The paper part of the layered material wicked water and hydrophobic channels were prepared on it as the NFC layer provided stiffness for the material. For analysing the interactions of proteins with cellulosic materials, the adsorption of proteins on NFC was analysed by the Surface Plasmon Resonance technique with NFC-model cellulose surfaces. BSA and human IgG were adsorbed on NFC model surfaces and the adsorption was determined to be influenced by electrostatic interaction at least at pH below the isoelectric point (IEP) of the respective protein. At pH above their IEP non-electrostatic interactions seemed to dominate the protein adsorption on NFC. Increased ionic strength of solution seemed to increase BSA adsorption on NFC at pH above its IEP due to reduced electrostatic repulsion between BSA and NFC. Additionally two different approaches were utilized to immobilize antibodies with specific orientation on NFC. The first approach utilized the specific interaction of protein A of Staphylococcus aureus with most IgG molecules. Protein A was pre-adsorbed on unmodified and CMC-modified NFC-surfaces and anti-human IgG was then adsorbed on top of the protein A treated NFC. These prepared bio interfaces were found to increase substantially the hIgG recognition sensitivity compared to a system where anti-hIgG was directly adsorbed on NFC. The other approach utilized the specific interaction of avidin with biotin. Chitosan-modified NFC surface was biotinylated after which avidin was allowed to adsorb on the surface. Biotinylated anti-hIgG was then adsorbed on the avidin treated surface. The avidin based bio interface also increased the recognition sensitivity of hIgG compared to the system with directly adsorbed anti-hIgG on NFC. The best bio interface for hIgG recognition in this work was the protein A based bio interface on CMC-modified NFC when protein A was adsorbed at pH 5.Kiinnostus selluloosapohjaisten materiaalien hyödyntämiseen immuno-diagnostisissa sovelluksissa on viime aikoina lisääntynyt. Tämän työn kirjallisuusosa käsittelee lyhyesti selluloosakuitujen rakennetta sekä joitain nanofibrilloidun selluloosan (NFC) ja NFC-kalvojen valmistusmenetelmiä, ominaisuuksia ja funktionalisointitapoja. Myös joitain uusia kehityssuuntia selluloosapohjaisten materiaalien hyödyntämisessä diagnostisissa sovelluksissa käsitellään. Kokeellisessa osassa kehitettiin mahdollinen kerrosrakenteinen tukimateriaali immunodiagnostisille testeille yhdistämällä paperiarkki ja NFC-kalvo. Kerrosrakenteisen materiaalin paperiosa imi vettä ja hydrofobisia kanavia pystyttiin valmistamaan sen päälle NFC-kalvon tarjotessa kaivattua jäykkyyttä materiaalille. Myös proteiinien adsorptiota NFC-mallipinnoille analysoitiin pintaplasmoniresonanssimenetelmän (SPR) avulla. Sähköstaattisten vuorovaikutusten havaittiin ohjaavan naudan seerumin albumiin (BSA) ja ihmisen IgG:n (hIgG) adsorptioita NFC:hen proteiinien isoelektrisen pisteen alapuolisessa pH:ssa. Proteiinien isoelektrisen pisteen yllä olevassa pH:ssa adsorptioon vaikutti myös muutkin kuin sähköstaattiset vuorovaikutukset sekä liuoksen suurempi ionivahvuus lisäsi BSA:n adsorptiota NFC:hen pienentyneen sähköstaattisen repulsion vuoksi. Lisäksi kahta eri lähestymistapaa hyödynnettiin vasta-aineiden orientoituun kiinnittämiseen NFC-pinnoille. Ensimmäisessä tavassa hyödynnettiin Staphylocccus aureksen proteiini A:n spesifistä vuorovaikutusta IgG molekyylien kanssa. Proteiini A:ta adsorboitiin ensin muokkaamattomalle ja CMC-muokatulle NFC-pinnalle, jonka jälkeen anti-hIgG:tä adsorboitiin sen päälle. Nämä biointerfaasit lisäsivät huomattavasti hIgG:n tunnistusta verrattuna systeemiin, jossa anti-hIgG oli suoraan adsorboitu NFC:hen. Toinen lähestymistapa hyödynsi avidiinin spesifistä vuorovaikutusta biotiinin kanssa. Kitosaanimuokattu NFC-pinta biotinyloitiin, jonka jälkeen sille adsorboitiin avidiinia. Biotinyloitua anti-hIgG:ta adsorboitiin sitten avidiinikäsitellylle NFC-pinnalle. Avidiini-pohjainen biointerfaasi lisäsi myös huomattavasti hIgG:n tunnistuskykyä sellaiseen systeemiin verrattuna, jossa anti-hIgG oli suoraan adsorboitu NFC-pinnalle. Paras biointerfaasi hIgG:n tunnistukseen tässä työssä oli proteiini A -pohjainen biointerfaasi CMC-muokatulla NFC-pinnalla, johon proteiini A oli adsorboitu pH 5:ssä

Väkivalta- ja uhkatilanteet maataloustukivalvonnoissa ja tarkastajien työssä jaksaminen

Maataloustukien valvontaa tekevät pääsääntöisesti työvoima- ja elinkeinokeskusten tarkastajat. Tässä työssä keskityttiin maataloustukivalvojien työhön ja heidän hyvinvointiinsa. Tutkimuksessa haluttiin selvittää, missä määrin ja millaista väkivaltaa tai sen uhkaa tarkastajat ovat työssään kohdanneet ja miten työnantajat ovat hoitaneet tarkastajien työturvallisuuden. Lisäksi selvitettiin, miten tarkastajat jaksavat työssään ja mitkä tekijät vahvistavat työssä jaksamista. Tutkimus toteutettiin vuosina 2007–2008. Tutkimusaineisto kerättiin kyselyllä, joka suunnattiin kaikille työvoima- ja elinkeinokeskusten maataloustukivalvontaa tekeville tarkastajille. Kysely toteutettiin tammikuun 2008 aikana. Kyselyn vastausprosentti oli 73 ja kohderyhmän koko 268 (N=268). Tämän tutkimuksen mukaan maataloustukivalvojien työhön liittyy turvallisuusriskejä. Joka viides (21 %) tarkastaja oli kohdannut jonkinlaista väkivaltaa tai sen uhkaa työssään. Väkivallan tai sen uhkan uhreista naisia oli 43 % ja miehiä 57 %. Kolme neljäsosaa (72 %) tarkastajista oli joutunut verbaalisen väkivallan kohteeksi. Lähes puolella (46 %) tarkastajista oli ongelmia työssä jaksamisessa. Työssä jaksamista vahvistavista tekijöistä nousivat selvästi esille työilmapiiri, työkaverit sekä perhe ja vapaa-aika. Tässä tutkimuksessa selvitettiin myös vaaratilanteiden jälkihoitoa työpaikoilla. Tutkimuksen mukaan työpaikoilla ei ole hoidettu vaaratilanteiden jälkihoitoa kunnolla. Kaikilla työpaikoilla ei ole myöskään laadittu riittäviä turvallisuusohjeita tarkastajille. Tutkimuksessa saatuja tuloksia voidaan hyödyntää valvontatyön kehittämisessä ja tarkastajien kouluttamisessa sekä heidän työhyvinvointinsa parantamisessa. Tutkimuksen tulosten pohjalta on laadittu tarkastajien turvallisuusohjeet Etelä-Savon työvoima- ja elinkeinokeskukselle, joka toimi tämän tutkimuksen toimeksiantajana

Serum Plant Sterols Associate with Gallstone Disease Independent of Weight Loss and Non-Alcoholic Fatty Liver Disease

Gallstone disease (GD) has been associated with low serum levels of plant sterols. We evaluated the impact of laparoscopic Roux-en-Y gastric bypass (LRYGB) and non-alcoholic fatty liver disease (NAFLD) on the association of GD with low levels of serum plant sterols. Two hundred forty-two consecutive morbidly obese patients were recruited to this prospective study. Histological analysis of liver biopsy to diagnose NAFLD was performed. Bile sample was taken during the LRYGB. Associations of GD with serum non-cholesterol sterol to cholesterol ratios, measured using gas liquid chromatography and with mRNA expression of genes participating in the cholesterol, bile, and fatty acid metabolism in the liver, were analyzed. Out of the 242 participants, 95 had GD. Lower weight (p = 0.002) and female sex (p = 0.0006) were associated with GD. Serum plant sterols, campesterol (p = 0.003), sitosterol (p = 0.002), and avenasterol (p = 0.015), were lower in patients with GD compared to those without GD. This association remained significant after adjustment for NAFLD, use of statin medication, and previous laparoscopic cholecystectomy (LCC). Levels of sitosterol (p = 0.001) and campesterol (p = 0.001) remained lower in obese individuals with GD also after obesity surgery. Liver mRNA expression of genes regulating cholesterol synthesis and bile metabolism was increased in individuals with GD. Serum plant sterols were lower in patients with GD independent of NAFLD, history of LCC, use of statin medication, and weight loss after LRYGB. Low serum plant sterols in patients with GD suggest potentially inherited alterations in sterol absorption and biliary transport in subjects susceptible for GD.Peer reviewe

Liraglutide demonstrates a therapeutic effect on mitochondrial dysfunction in human SGBS adipocytes in vitro

Aims: Liraglutide (LG), a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been shown to improve white adipose tissue mitochondrial metabolism in mice but not in human adipocytes. Therefore, we explored whether LG has therapeutic efficacy in mitochondrial dysfunction in human adipocytes in vitro.Methods: We tested the effects of short-term (ST-LG: 24 h) and long-term (LT-LG: D0-15 days) treatments in human SGBS adipocytes on mitochondrial respiration, mRNA and protein expression. GLP-1R inhibition was investigated by the co-treatment of GLP-1R inhibitor, exendin 9-39 (Ex9-39) and ST-LG treatment. We also explored the ability of ST-LG to alleviate mitochondrial dysfunction induced by tumor necrosis factor-alpha (TNF alpha).Results: LT-LG treatment induced the formation of smaller lipid droplets and increased the expression of genes related to lipolysis. Both ST-LG and LT-LG treatments promoted mitochondrial respiration. Additionally, LT-LG treatment increased the expression of a brown adipocyte marker, uncoupling protein 1 (UCP-1), and the markers of mitochondrial biogenesis. Interestingly, ST-LG rescued TNF alpha-induced defects in mitochondrial energy meta-bolism and inflammation in SGBS adipocytes.Conclusion: LG stimulates mitochondrial respiration and biogenesis in human adipocytes, potentially via UCP-1-mediated adipocyte browning. Importantly, our study demonstrates for the first time that LG has a therapeutic potential on mitochondrial activity in human adipocytes.Peer reviewe