The ubiquitin-like modifier FAT10 is induced in MASLD and impairs the lipid-regulatory activity of PPARα

BACKGROUND AND AIMS

Peroxisome Proliferator-Activated Receptor α (PPARα) is a key regulator of hepatic lipid metabolism and therefore a promising therapeutic target against Metabolic-dysfunction Associated Steatotic Liver Diseases (MASLD). However, its expression and activity decrease during disease progression and several of its agonists did not achieve sufficient efficiency in clinical trials with, surprisingly, a lack of steatosis improvement. Here, we identified the Human leukocyte antigen-F Adjacent Transcript 10 (FAT10) as an inhibitor of PPARα lipid metabolic activity during MASLD progression.

APPROACH AND RESULTS

In vivo, the expression of FAT10 is upregulated in human and murine MASLD livers upon disease progression and correlates negatively with PPARα expression. The increase of FAT10 occurs in hepatocytes in which both proteins interact. FAT10 silencing in vitro in hepatocytes increases PPARα target gene expression, promotes fatty acid oxidation and decreases intra-cellular lipid droplet content. In line, FAT10 overexpression in hepatocytes in vivo inhibits the lipid regulatory activity of PPARα in response to fasting and agonist treatment in conditions of physiological and pathological hepatic lipid overload.

CONCLUSIONS

FAT10 is induced during MASLD development and interacts with PPARα resulting in a decreased lipid metabolic response of PPARα to fasting or agonist treatment. Inhibition of the FAT10-PPARα interaction may provide a means to design potential therapeutic strategies against MASLD.

Topical ropivacaine for analgesia of aplasia cutis congenita in newborns with hereditary epidermolysis bullosa

Aplasia cutis congenita (ACC) in patients with hereditary epidermolysis bullosa (EB) is often associated with major pain. We report our experience with using topical ropivacaine during dressing in newborns with ACC. Eight full-term newborns with EB and ACC were hospitalized in a neonatal intensive care unit for severe pain during dressing despite the use of paracetamol, opioids (n = 8) or ketamine (n = 7). Topical xylocaine was poorly tolerated and not effective. Ropivacaine 2 mg/ml was used directly in contact with the ACC, with a maximum 1 mg/kg/day, which enabled care without the child crying. No immediate or late systemic toxicity was observed. Topical ropivacaine 0.2% appears to be an interesting topical analgesic, with good clinical tolerance and rapid action, in newborns with ACC and EB. These data need to be confirmed in a prospective study including pharmacokinetics evaluations.

Audit sur le bon usage du citalopram

Malgré les recommandations de l’ANSM sur le risque torsadogène du citalopram, l’équipe pharmaceutique du centre hospitalier a émis de nombreuses interventions pharmaceutiques (IP) devant des erreurs médicamenteuses de prescription. L’objectif a été d’évaluer le suivi des recommandations durant l’hospitalisation, dans la lettre de sortie (LS) et en ville par le médecin traitant (MT). L’audit rétrospectif a été réalisé sur une période d’un an. Ont été inclus les patients pour lesquels les IP concernaient des contre-indications avec le citalopram (pathologies cardiovasculaires, interactions médicamenteuses). Au total, 51 IP ont été émises : 54,9 % ont été appliquées par le praticien (citalopram substitué par paroxétine dans trois quarts des cas) ; 35,3 % des IP n’ont pas été suivies et 9,8 % étaient non-applicables. Parmi les patients avec IP suivies, 15 (53,5 %) avaient des LS expliquant la réévaluation des prescriptions aux MT ; 5 (17,9 %) avaient des LS sans mention de la réévaluation avec maintien de la contre-indication ; 8 (28,6 %) n’avaient pas de LS. Neuf des 15 patients avec LS exhaustive ont été ré-hospitalisés dans l’année sans contre-indication dans le traitement d’entrée (8 par maintien de la paroxétine et un par levée de l’interaction médicamenteuse). Trois des 5 patients sans notion de réévaluation dans la LS ont été ré-hospitalisés avec persistance de la contre-indication dans le traitement d’entrée. Les MT appliquent largement les recommandations de la LS, soulignant l’efficacité d’une collaboration pluriprofessionnelle ville-hôpital et le rôle primordial du pharmacien dans les conciliations médicamenteuses de sortie. Celle-ci sera prochainement mise en place dans l’établissement et prévoit l’intégration des fiches de conciliation aux LS pour informer les MT des réévaluations médicamenteuses. Un thésaurus d’interactions médicamenteuses décrivant le niveau d’interaction et la conduite à tenir pour les médicaments à risque d’allongement de l’espace QT a été créé comme outil d’aide à la prescription.

Selective logging, habitat quality and home range use by sympatric gorillas and chimpanzees: a case study from an active logging concession in Southeast Cameroon

We examined range use by great apes during logging activities and investigated associations between local variations in ape abundance and changes in the structure of the habitat or in the availability of fruits after disturbances. We carried out two annual censuses of western lowland gorilla (G. g. gorilla) and chimpanzee populations (Pan t. troglodytes) in an active logging concession in Southeast Cameroon. The results suggest that gorillas may adapt their range use to avoid most recently logged compartments, while chimpanzees appear to be more spatially resilient to logging. In our study site, selective logging affected 10% of the forest. After logging, gorillas nested in all types of vegetation, while chimpanzees nested exclusively in mixed mature forest. Fruit availability was not affected by logging and did not explain the distribution of ape nests in the study area.

Estimated energy intake, macronutrient intake and meal pattern of Flemish adolescents

OBJECTIVE

To describe the energy and macronutrient intake and the meal patterns of Flemish adolescents, aged 13-18 y.

METHODS

A 7 day estimated food record was administered to the whole sample.

SETTING

Secondary schools in the city of Ghent, Belgium.

SUBJECTS

A total of 341 adolescents (13-18 y) selected by a multistage clustered sampling (participation: 72.7%).

MAIN RESULTS

A significant increase with age was observed in total energy intake in adolescent boys (P<0.01), but not in girls. The energy distribution over the macronutrients showed no significant difference between boys and girls. On average, 35.7% (s.d. 4.81%) of energy came from total fat and 15.4% (s.d. 2.46%) from saturated fatty acids; 49.0% (s.d. 5.28%) from total carbohydrates with 25.1% (s.d. 4.49%) from complex carbohydrates and 23.9% (s.d. 5.86%) from free sugars. The energy contribution of alcohol in the 16-18 y-old-group was significantly higher as compared with the 13-15 y-old-group, for both boys and girls. Snacks between meals accounted for almost 20% of the total energy intake. Lunch and dinner were characterized by high total fat content.

CONCLUSION

These students consumed a diet high in total fat and in saturated fatty acids and also high in mono- and disaccharides. Observed mean intakes deviate considerably from the Belgian dietary guidelines. A low energy intake at breakfast was observed, while a higher proportion of energy was derived from snacks.

Stir bar sorptive extraction for the determination of ppq-level traces of organotin compounds in environmental samples with thermal desorption-capillary gas chromatography--ICP mass spectrometry

The extraction and preconcentration capabilities of a new extraction technique, stir bar sorptive extraction, were combined with the separation power of capillary gas chromatography (CGC) and the low limits of detection (LODs) of inductively coupled plasma mass spectrometry (ICPMS) for the determination of the organotin compounds tributyltin (TBuT) and triphenyltin (TPhT) in aqueous standard solutions, harbor water, and mussels (after digestion with tetramethylammonium hydroxide). Throughout, tripropyltin for TBuT and tricyclohexyltin for TPhT were used as internal standards to correct for variations in the derivatization and extraction efficiency. Calibration was accomplished by means of single standard addition. Derivatization to transform the trisubstituted compounds into sufficiently volatile compounds was carried out with sodium tetraethylborate. The compounds were extracted from their aqueous matrix using a stir bar of 1-cm length, coated with 55 microL of poly(dimethylsiloxane) (PDMS). After 15 min of extraction, the stir bar was desorbed in a thermal desorption unit at 290 degrees C for 15 min, during which the compounds were cold-trapped on a precolumn at -40 degrees C. Flash heating was used to rapidly transfer the compounds to the GC where they were separated on a capillary column with a PDMS coating. After separation, the compounds were transported to the ICP by means of a homemade heated (270 degrees C) transfer line. Monitoring of the 120Sn+ signal by ICPMS during the run of the GC provided extremely low LODs for TPhT in water: 0.1 pg L(-1) (procedure) and 10 fg L(-1) (instrumental) and a repeatability of 12% RSD (n = 10). In harbor water, concentrations of 200 pg L(-1) for TBuT and 22 pg L(-1) for TPhT were found. In fresh mussels, a concentration of 7.2 ng g(-1) (dry weight) TPhT was found. The accuracy of the method was checked by the determination of TPhT in CRM477 (mussel tissue) and comparison of the result to that of an analysis of the same material with a classical liquid/liquid extraction with isooctane.

Automated capillary gas chromatographic system to monitor ethylene emitted from biological materials

An automated capillary gas chromatographic system to measure ethylene emitted from biological materials is presented. The system consists of an on-line sampling device, a thermodesorption preconcentration apparatus and a capillary gas chromatograph with a flame ionization detection system. The limit of detection achievable on the GC system alone is 5 pg ethylene. The use of the strong Carboxen 1000 adsorbent at a sampling temperature as low as -50 degrees C allows sampling of volumes up to a few liters. Ethylene concentrations at low ppt levels can be accurately and reproducibly determined.

Uncoupling between beta-adrenoceptors and adenylate cyclase in dog ischemic myocardium

We evaluated the effects of ischemic injury on the myocardial adenylate cyclase system, 5 h after ligation of the left anterior descending coronary in 5 anesthetized dogs. Crude cardiac membrane preparations were isolated from control and ischemic areas of ventricular myocardium and tested for: 1. L-(125I)iodocyanopindolol binding, in the absence and presence of +/- -isoprenaline and GTP, and 2. adenylate cyclase activity. The density of beta-adrenoceptors increased by 35% in membranes from ischemic areas while the proportion of receptors in a high affinity state for +/- -isoprenaline decreased from 43% to 20%. Adenylate cyclase activities in the basal state and under stimulation with NaF, forskolin, Gpp(NH)p, +/- -isoprenaline and VIP were all markedly and similarly reduced, being only about 30% of comparable activities in membranes from control areas. The +/- -isoprenaline subsensitivity of cardiac adenylate cyclase can, thus, be attributed to a defective enzymatic system and not to a reduction in the number of beta-adrenoceptors implying that the internal components of the system were more sensitive to acute ischemia than the outward oriented hormone receptors. It is tempting to ascribe this uncoupling to a functional depletion in the guanine nucleotide-binding regulatory protein Ns that might reflect a loss of high energy phosphate stores including GTP.

Amiodarone. Biochemical aspects and haemodynamic effects

The mechanisms underlying the non-competitive beta-antagonistic properties of amiodarone were investigated, and the haemodynamic responses to exercise following the administration of oral amiodarone or intravenous propranolol were compared in dogs with a healed myocardial infarction submitted to a graded treadmill exercise. In radioligand binding studies, amiodarone, up to 10 mumol/L did not compete with 125I-iodocyanopindolol for binding to rat heart beta-adrenoceptors. Exposure of cardiac membranes to greater concentrations of amiodarone induced a significant decrease in the number of beta-adrenoceptors without affecting their affinity for 125I-iodocyanopindolol. Similar results were observed ex vivo, in rats after single or multiple dose administration. When added in vitro to rat heart membranes, amiodarone non-competitively inhibited the activation of adenylate cyclase by isoprenaline, glucagon and secretin. Stimulation of adenylate cyclase by those agents which act at more internal sites in the sarcolemmal membrane such as GppNHp, sodium fluoride or forskolin, was much less affected by amiodarone. In dogs performing at a submaximal work level, amiodarone significantly reduced heart rate and tended to increase coronary flow and to reduce left ventricular end-diastolic pressure, but did not affect left ventricular dP/dt. During submaximal exercise, propranolol had similar effects on heart rate, but dramatically reduced myocardial contractility.