Effect of Ajwa date seed powder on visceral fat depots and inflammatory response in high fat fed Sprague Dawley female rats.

ABSTRACT Background: Central obesity a worldwide metabolic and cosmetic problem poses significant health risk. Ajwa date seed has antioxidant property and its high fiber content may prevent fat absorption and reduce fat deposition. Objective: To evaluate the effect of Ajwa date seed powder on visceral fat depots and inflammatory response in high fat fed Sprague Dawley female rats. Methodology: Thirty-six healthy rats of four weeks age were divided into three groups and followed for 12 weeks. Group A (normal control) received regular diet. Group B (HFD control) received high fat diet, while group C (HFD+Ajwa group) received high fat diet along with 2% Ajwa date seed powder. Body weight was measured weekly. Blood sample was drawn for the estimation of serum IL-6 and leptin levels by ELISA method at 12th week. After which rats were euthanized; perinephric fat was removed and weighed in grams. Results: HFD+Ajwa group gained less body weight as compared to HFD control group (p value = 0.012). There was a remarkable reduction in perinephric fat weight (p value ≤ 0.001) and level of IL-6 in HFD+Ajwa group (p value ≤ 0.001) as compared to HFD control. There was no significant difference in serum leptin level of the rats of all groups (p value = 0.567). Conclusion: Ajwa date seed can prevent visceral adiposity and gain in body weight. Moreover, it has anti-inflammatory effect; but no significant effect on satiety hormone. Key Words: Obesity, Visceral fat, P. dactylifera L (Ajwa date) seed, IL-6, Leptin.

Triglyceride Saturation in Patients at Risk of NASH and NAFLD: A Cross-Sectional Study

Chemical shift magnetic resonance imaging (MRI) is commonly used to estimate the amount of fat in tissues, namely the proton density fat fraction (PDFF). In addition to PDFF, the type of fat can be inferred and characterized in terms of the number of double bonds (NDB), number of methylene-interrupted double bonds (NMIDB) and the chain length (CL) of the fatty acid chains. The saturation index is potentially a marker for metabolic disorders. This study assesses the feasibility of estimating these parameters independently or in a constrained manner. Correlations with spectroscopy were measured in 109 subjects’ subcutaneous and visceral fat depots (p = 2 × 10−28), and with the NAFLD Activity Score (NAS) from histological evaluation of biopsies. The findings indicate that imaging estimates are comparable to spectroscopy (p = 0.0002), but there is no significant association of NDB with NAS (p = 0.1).

The Effect of a Sustained High-Fat Diet on the Metabolism of White and Brown Adipose Tissue and Its Impact on Insulin Resistance: A Selected Time Point Cross-Sectional Study

(1) Background: studies on the long-term dynamic changes in fat depot metabolism in response to a high-fat diet (HFD) on hepatic lipid deposition and insulin resistance are sparse. This study investigated the dynamic changes produced by HFD and the production of dysfunctional fat depots on insulin resistance and liver lipid metabolism. (2) Methods: mice fed a chow or HFD (45% kcal fat) diet had three fat depots, liver, and blood collected at 6, 10, 20, and 30 weeks. Anthropometric changes and gene markers for adipogenesis, thermogenesis, ECM remodeling, inflammation, and tissue insulin resistance were measured. (3) Results: early responses to the HFD were increased body weight, minor deposition of lipid in liver, increased adipocyte size, and adipogenesis. Later changes were dysfunctional adipose depots, increased liver fat, insulin resistance (shown by changes in ITT) accompanied by increased inflammatory markers, increased fibrosis (fibrosis > 2-fold, p < 0.05 from week 6), and the presence of crown cells in white fat depots. Later, changes did not increase thermogenic markers in response to the increased calories and decreased UCP1 and PRDM16 proteins in WAT. (4) Conclusions: HFD feeding initially increased adipocyte diameter and number, but later changes caused adipose depots to become dysfunctional, restricting adipose tissue expansion, changing the brown/beige ratios in adipose depots, and causing ectopic lipid deposition and insulin resistance.

Effects of voluntary exercise on the expression of browning markers in visceral and subcutaneous fat tissue of normotensive and spontaneously hypertensive rats

High physical activity is important to optimize the function of adipose tissue. Dysfunctional adipose tissue contributes to the development of metabolic stress, chronic inflammation, and hypertension. To improve our current understanding of the interaction between physical exercise and adipose tissue, we analyzed the effect of 10 months voluntary running wheel activity of rats on uncoupling protein (UCP) 1 negative white adipose tissue (visceral and subcutaneous adipose tissue, VWAT and SWAT). Analysis was performed via RT-PCR and immunoblot from adipose tissues depicted from adult normotensive and spontaneously hypertensive female rats. UCP1 negative VWAT differed from UCP1 positive WAT and brown adipose tissue (BAT) from interscapular fat depots, by lacking the expression of UCP1 and low expression of Cidea, a transcriptional co-activator of UCP1. High physical activity affected the expression of five genes in SWAT (Visfatin (up), RBP5, adiponectin, Cidea, and Nrg4 (all down)) but only one gene (Visfatin, up) in VWAT. Furthermore, the expression of these genes is differentially regulated in VWAT and SWAT of normotensive and spontaneously hypertensive rats (SHR) under sedentary conditions (UCP2) and exercise (Visfatin, Cidea, Nrg4). Keeping the animals after 6 months of voluntary exercise under observation for an additional period of 4 months without running wheels, Visfatin, Cidea, and Nrg4 were stronger expressed in VWAT of SHRs than in sedentary control rats. In summary, our study shows that SWAT is more responsible to exercise than VWAT.

Epicardial adipose tissue as a mediator of cardiac arrhythmias

Obesity is associated with higher risks of cardiac arrhythmias. Although this may be partly explained by concurrent cardiometabolic ill-health, growing evidence suggests that increasing adiposity independently confers risk for arrhythmias. Amongst fat depots, epicardial adipose tissue (EAT) exhibits a proinflammatory secretome, and given the lack of fascial separation, has been implicated as a transducer of inflammation to the underlying myocardium. The present review explores the mechanisms underpinning adverse electrophysiological remodelling as a consequence of EAT accumulation and the consequent inflammation. We first describe the physiological and pathophysiological function of EAT and its unique secretome, and subsequently discuss the evidence for ionic channel and connexin expression modulation as well as fibrotic remodelling induced by cytokines and free fatty acids that are secreted by EAT. Finally, we highlight how weight reduction and regression of EAT volume may cause reverse remodelling to ameliorate arrhythmic risk.

Genomic engineering of adipocytes with CRISPR/Cas9 delivery particles for ex vivo therapeutic approach for type 2 diabetes

Η παχυσαρκία και ο διαβήτης τύπου 2 (ΔΤ2) σχετίζονται με διαταραχές στην ομοιόσταση της γλυκόζης και των λιπιδίων η οποία ρυθμίζεται από την ινσουλίνη και προκαλεί σοβαρές επιπλοκές συμπεριλαμβανομένων καρδιαγγειακών νοσημάτων και στεατοηπατίτιδας. Ο συστημικός μεταβολισμός της γλυκόζης ρυθμίζεται από τους διακριτούς λιπώδεις ιστούς (fat depots), στις οποίες συμπεριλαμβάνονται δύο κυρίως τύποι λιπώδους ιστού το λευκό λίπος και το φαιό (ή καφέ) λίπος. Το μεν λευκό λίπος αποτελείται από τα «λευκά» λιποκύτταρα και έχει ρόλο αποθήκευσης της ενέργειας σε μορφή λιπιδίων ενώ το φαιό λίπος αποτελείται από τα «φαιά» και «μπεζ» λιποκύτταρα. Tα κύτταρα αυτά καταναλώνουν την αποθηκευμένη ενέργεια για την παραγωγή θερμότητας και εκφράζουν την πρωτεΐνη αποσύζευξης 1 (UCP1) καθώς και πλήθος εκκρινόμενων παραγόντων που ευνοούν τον μεταβολισμό. Έχει περιγραφή στη βιβλιογραφία ότι η μεταμόσχευση φαιού λιπώδους ιστού ή ποντικίσιων ή αθανατοποιημένων ανθρώπινων φαιών λιποκυττάρων σε παχύσαρκους μύες βελτιώνει την ανοχή στη γλυκόζη. Ωστόσο, η εφαρμογή μιας ανάλογης θεραπευτικής παρέμβασης στον άνθρωπο δεν έχει καταστεί δυνατή καθώς η διαθεσιμότητα των πρωτογενών ανθρώπινων φαιών/μπεζ λιποκυττάρων είναι εξαιρετικά περιορισμένη. Στην παρούσα διατριβή, χρησιμοποίησα μεθόδους πολλαπλασιασμού σε μεγάλη κλίματα ανθρώπινων πρόγονων λιποκυττάρων από εξαιρετικά μικρά δείγματα ανθρώπινου λιπώδους ιστού. Στα ανθρώπινα πρόδρομα λιποκύτταρα, παράλληλα με τα ποντικίσια, εφάρμοσα τροποποίηση του γονιδιώματος με τη χρήση ομαδοποιημένων με τακτά μεσοδιαστήματα σύντομων παλινδρομικών μοτίβων (CRISPR). O στόχος αυτής της γονιδιακής τροποποίησης είναι να απενεργοποιήσει γονίδια που φυσιολογικά παρεμποδίζουν τη μετατροπή των λιποκυττάρων από λευκά σε φαιά. Συνεπώς, η απώλεια της λειτουργικότητας αυτών των γονιδίων αναμένεται να προκαλέσει την μετατροπή των λευκών λιποκυττάρων σε φαιά που είναι ωφέλιμα για τον μεταβολισμό της γλυκόζης. Σημαντικοί δευτερεύοντες στόχοι της στρατηγικής της θεραπείας είναι η παράκαμψη της ανοσογονικότητας των συστατικών CRISPR και της γονιδιακής τροποποίησης σε ανεπιθύμητους ιστούς καθώς και η ελαχιστοποίηση της ανεπιθύμητης τροποποίησης σε περιοχές του γονιδιώματος εκτός των στοχευμένων. Στην παρούσα εργασία, ανέπτυξα και μεγιστοποίησα τη μέθοδο ex vivo μεταφοράς στα κύτταρα – στόχους (λιποκύτταρα) των συμπλεγμάτων στρεπτοκοκκικού Cas9 ενζύμου και στου οδηγού sgRNA, ούτως ώστε να επιτυγχάνεται η ταχύτατη διάσπασή τους αμέσως μετά την τροποποίηση του γονιδίου – στόχο. Για τη μεταφορά των συμπλεγμάτων αυτών, χρησιμοποιήθηκε η μέθοδος της ηλεκτροδιάτρησης με αποτελεσματικότητα τροποποίησης που πλησιάζει το 100%. Κατόπιν ελέγχου πλήθους υποψηφίων γονιδίων – στόχων που αναφέρονται στη βιβλιογραφία, εντοπίστηκε ως ο πλέον υποσχόμενος στόχος το γονίδιο της πρωτεΐνης 1 που αναγνωρίζει πυρηνικούς υποδοχείς (NRIP1). Τα λιποκύτταρα στα οποία απενεργοποιήθηκε το Nrip1 γονίδιο (NRIP1 Knock-out, NRIP1KO) επάγουν την έκφραση ενός «φαιού» γονιδιακού προφίλ το οποίο συμπεριλαμβάνει την πρωτεΐνη UCP1 και ορισμένους εκκρινόμενους παράγοντες. Στη συνέχεια, χαρακτήρισα in vitro το φαινότυπο των τροποποιημένων κυττάρων με πλήθος δοκιμασιών όπως έκφραση γνωστών γονιδίων που σχετίζονται με τη θερμογένεση, μιτοχονδριακή αναπνοή, οξέωση λιπιδίων, εκκρινομένους παράγοντες, δοκιμασία κατανάλωση οξυγόνου, έκφραση της πρωτεΐνης UCP1, τόσο στο ποντικίσια όσο και στο ανθρώπινα κύτταρα. Τέλος, τα βελτιστοποιημένα με CRISPR ποντικίσια ή ανθρώπινα «φαιά» λιποκύτταρα εμφυτεύθηκαν σε ποντίκια – λήπτες τα οποία λάμβαναν διατροφή εμπλουτισμένη σε λίπος για την πρόκληση διαβήτη τύπου 2. Τα εμφυτεύματα των τροποποιημένων κυττάρων έδειξαν μικρότερη συσσώρευση σωματικού λίπους μικρότερη συσσώρευση τριγλυκεριδίων στο ηπατικό παρέγχυμα καθώς επίσης βελτίωσαν την ανοχή στη γλυκόζη συγκριτικά με τα ποντίκια – μάρτυρες που έλαβαν εμφυτεύματα μη τροποποιημένων λιποκυττάρων. Παράλληλα, όπως απεδείχθη η παρουσία των συστατικών της CRISPR τροποποίησης ήταν παροδική στα κύτταρα-στόχους καθώς η ενδονουκλεάση Cas9 αποδομείται και δεν είναι ανιχνεύσιμη με ηλεκτροφόρηση ολικής πρωτεΐνης πριν τις εμφυτεύσεις. Τα ευρήματα αυτά υποδεικνύουν μια θεραπευτική στρατηγική για τη βελτίωση της ομοιόστασης του μεταβολισμού μέσω της γονιδιακής τροποποίησης με CRISPR ανθρώπινων λιποκυττάρων χωρίς την έκθεση του ασθενούς στα ανοσογόνα και δυνητικά επιβλαβή ένζυμο Cas9 και οδηγό sgRNA και άλλων οχημάτων μεταφοράς των συστατικών CRISPR.

MAGRARIO: A NEW GENOTYPE TO PRODUCE QUALITY SHEEP MEAT

Generally there is poor tradition to produce and to commercialize heavy lean lamb carcasses. To achieve a better product for the ovine meat market Ideal (Polwarth) breed ewes were backcrossed to Texel breed rams (breed recognized to reduce carcass fat). Ideal breed (I) is one of the most ordinary breeds in Argentina. However, when their lambs are reared in feed-lot conditions, a high fat content is found in their lamb carcasses. After three generations of backcrosses followed by a breeding program for increase male lamb weaning weight and female fertility a new genotype was obtained for the local ovine meat production systems. This new genotype registered as Magrario (M) was obtained at Villarino Field Station of UNR (Zavalla, Santa Fe, 33º S, 61º W). It was verify that M produced more lean meat than I breed under feet lot conditions. M rams were introduced in flocks of Hampshire Down (HD) breed to evaluate lamb crosses with lean meat. Genotype M was compared under feed lot conditions with HD lambs during two months in the post weaning. Also crosses (MxHD), (MxI) and (IxHD) were evaluated in the same conditions. At the end of the experiment ultrasonic methods were used to evaluate fat depot on Longissimus dorsi. The (MxHD) showed a reduction of 20% respecting to HD. These results suggested that M genotype could be a useful paternal genotype to reduce fat depots when the aim is to produce lamb crosses under feed lot conditions in a short period of time. Key words: ovine, lean meat, feed lot, crossing.

Wt1 haploinsufficiency induces browning of epididymal fat and alleviates metabolic dysfunction in mice on high-fat diet

Aims/hypothesis Despite a similar fat storing function, visceral (intra-abdominal) white adipose tissue (WAT) is detrimental, whereas subcutaneous WAT is considered to protect against metabolic disease. Recent findings indicate that thermogenic genes, expressed in brown adipose tissue (BAT), can be induced primarily in subcutaneous WAT. Here, we investigate the hypothesis that the Wilms tumour gene product (WT1), which is expressed in intra-abdominal WAT but not in subcutaneous WAT and BAT, suppresses a thermogenic program in white fat cells. Methods Heterozygous Wt1 knockout mice and their wild-type littermates were examined in terms of thermogenic and adipocyte-selective gene expression. Glucose tolerance and hepatic lipid accumulation in these mice were assessed under normal chow and high-fat diet conditions. Pre-adipocytes isolated from the stromal vascular fraction of BAT were transduced with Wt1-expressing retrovirus, induced to differentiate and analysed for the expression of thermogenic and adipocyte-selective genes. Results Expression of the thermogenic genes Cpt1b and Tmem26 was enhanced and transcript levels of Ucp1 were on average more than tenfold higher in epididymal WAT of heterozygous Wt1 knockout mice compared with wild-type mice. Wt1 heterozygosity reduced epididymal WAT mass, improved whole-body glucose tolerance and alleviated severe hepatic steatosis upon diet-induced obesity in mice. Retroviral expression of WT1 in brown pre-adipocytes, which lack endogenous WT1, reduced mRNA levels of Ucp1, Ppargc1a, Cidea, Prdm16 and Cpt1b upon in vitro differentiation by 60–90%. WT1 knockdown in epididymal pre-adipocytes significantly lowered Aldh1a1 and Zfp423 transcripts, two key suppressors of the thermogenic program. Conversely, Aldh1a1 and Zfp423 mRNA levels were increased approximately five- and threefold, respectively, by retroviral expression of WT1 in brown pre-adipocytes. Conclusion/interpretation WT1 functions as a white adipocyte determination factor in epididymal WAT by suppressing thermogenic genes. Reducing Wt1 expression in this and other intra-abdominal fat depots may represent a novel treatment strategy in metabolic disease. Graphical abstract

Co-Evolution of Breast Milk Lipid Signaling and Thermogenic Adipose Tissue

Breastfeeding is a unique and defining behavior of mammals and has a fundamental role in nourishing offspring by supplying a lipid-rich product that is utilized to generate heat and metabolic fuel. Heat generation from lipids is a feature of newborn mammals and is mediated by the uncoupling of mitochondrial respiration in specific fat depots. Breastfeeding and thermogenic adipose tissue have a shared evolutionary history: both have evolved in the course of homeothermy evolution; breastfeeding mammals are termed “thermolipials”, meaning “animals with warm fat”. Beyond its heat-producing capacity, thermogenic adipose tissue is also necessary for proper lipid metabolism and determines adiposity in offspring. Recent advances have demonstrated that lipid metabolism in infants is orchestrated by breast milk lipid signals, which establish mother-to-child signaling and control metabolic development in the infant. Breastfeeding rates are declining worldwide, and are paralleled by an alarming increase in childhood obesity, which at least in part may have its roots in the impaired metabolic control by breast milk lipid signals.

Opposing Immune-Metabolic Signature in Visceral Versus Subcutaneous Adipose Tissue in Patients with Adenocarcinoma of the Oesophagus and the Oesophagogastric Junction

Oesophageal adenocarcinoma (OAC) is an exemplar model of obesity-associated cancer. Previous work in our group has demonstrated that overweight/obese OAC patients have better responses to neoadjuvant therapy, but the underlying mechanisms are unknown. Unravelling the immune–metabolic signatures of adipose tissue may provide insight for this observation. We hypothesised that different metabolic pathways predominate in visceral (VAT) and subcutaneous adipose tissue (SAT) and inflammatory secretions will differ between the fat depots. Real-time ex vivo metabolic profiles of VAT and SAT from 12 OAC patients were analysed. These samples were screened for the secretion of 54 inflammatory mediators, and data were correlated with patient body composition. Oxidative phosphorylation (OXPHOS) was significantly higher in VAT when compared to SAT. OXPHOS was significantly higher in the SAT of patients receiving neoadjuvant treatment. VEGF-A, VEGF-C, P1GF, Flt-1, bFGF, IL-15, IL-16, IL-17A, CRP, SAA, ICAM-1, VCAM-1, IL-2, IL-13, IFN-γ, and MIP-1β secretions were significantly higher from VAT than SAT. Higher levels of bFGF, Eotaxin-3, and TNF-α were secreted from the VAT of obese patients, while higher levels of IL-23 and TARC were secreted from the SAT of obese patients. The angiogenic factors, bFGF and VEGF-C, correlated with visceral fat area. Levels of OXPHOS are higher in VAT than SAT. Angiogenic, vascular injury and inflammatory cytokines are elevated in VAT versus SAT, indicating that VAT may promote inflammation, linked to regulating treatment response.