Fat Formation Research Articles

MiR-9-5p promotes rabbit preadipocyte differentiation by suppressing leptin gene expression

BackgroundMicroRNAs (miRNAs) are a class of small non-coding RNAs, which participate in the regulation of cell differentiation. Previous studies have demonstrated that miR-9-5p plays a key role in cancer cell development, but the mechanisms by which miR-9-5p regulates adipogenesis remain poorly understood. The present study intended to investigate its significance in producing rabbits with high-quality meat by observing the regulatory effect of miR-9-5p in preadipocytes and finding the related targets.MethodsIn this study, a dual-luciferase reporter assay was employed to validate the targeting relationship between miR-9-5p and leptin gene. We also utilized quantitative reverse transcription PCR (qRT-PCR), western blot, oil red-O staining assay, and determination of triglyceride content to analyze the regulation of miR-9-5p and leptin gene during adipocyte differentiation.ResultsThe analysis demonstrated that during preadipocyte differentiation, miR-9-5p was up-regulated and the fat formation related biomarkers, i.e., fatty acid-binding protein 4 (FABP4), CCAAT-enhancer binding protein α (C/EBPα), and peroxisome proliferator activated receptor γ (PPARγ) were also up-regulated. Meanwhile, the oil red-O staining assay revealed that the accumulation of lipid droplets increased. We also explored the expression pattern and role of miR-9-5p in adipogenesis using white pre-adipocytes. The results showed that miR-9-5p was up-regulated during preadipocyte differentiation, and overexpression of miR-9-5p enhanced lipid accumulation. Furthermore, we found that the overexpression of miR-9-5p significantly up- regulated the expression of marker genes, PPARγ, C/EBPα and FABP4, and increased the protein levels of PPARγ and triglyceride content. The results suggest that miR-9-5p might be involved in the regulation of rabbit preadipocyte differentiation. We predicted that leptin is the target gene of miR-9-5p, by using bioinformatics tools and the conclusion was validated by a luciferase reporter assay. Finally, we verified that the knock-down of leptin by si-leptin promoted preadipocyte differentiation in rabbits.ConclusionThe results of the present study indicate that miR-9-5p regulates white preadipocyte differentiation in rabbits by targeting the leptin gene.

Effect of dietary nutrition on tail fat deposition and evaluation of tail-related genes in fat-tailed sheep

Abstract Background The effects of dietary nutrition on tail fat deposition and the correlation between production performance and the Hh signaling pathway and OXCT1 were investigated in fat-tailed sheep. Tan sheep were fed different nutritional diets and the variances in tail length, width, thickness and tail weight as well as the mRNA expression of fat-related genes (C/EBPα, FAS, LPL, and HSL) were determined in the tail fat of sheep at three different growth stages based on their body weight. Furthermore, the correlations between tail phenotypes and the Hedgehog (Hh) signaling pathway components (IHH, PTCH1, SMO, and GLI1) and OXCT1 were investigated. Results C/EBPα, FAS, LPL, and HSL were expressed with differences in tail fat of sheep fed different nutritional diets at three different growth stages. The results of the two-way ANOVA showed the significant effect of nutrition, stage, and interaction on gene expression, except the between C/EBPα and growth stage. C/EBPα, FAS, and LPL were considerably correlated with the tail phenotypes. Furthermore, the results of the correlation analysis demonstrated a close relationship between the tail phenotypes and Hh signaling pathway and OXCT1. Conclusions The present study demonstrated the gene-level role of dietary nutrition in promoting tail fat deposition and related tail fat-related genes. It provides a molecular basis by which nutritional balance and tail fat formation can be investigated and additional genes can be identified. The findings of the present study may help improve the production efficiency of fat-tailed sheep and identify crucial genes associated with tail fat deposition. How to cite: Zeng J, Zhou S, Yang Y, et al. Effect of dietary nutrition on tail fat deposition and evaluation of tail-related genes in fat-tailed sheep. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.05.004 .

Production and characterization of infant milk formula powders: A review

Infant milk formula (IMF) products intend to simulate the composition of human milk and meet the nutritional requirements of infants until they become familiar with complementary foods. In addition to meeting nutritional requirements, IMF powders should be stable and rehydrate well up to their use-by date. These requirements can be met by developing balanced formulations and optimizing the parameters used during processing, handling, and storage. Ingredients such as lactoferrin, milk fat globule membrane, probiotics, and prebiotics are often incorporated in some IMF powders. Stability of IMF powders is essential, and it is often compromised by handling and storage at suboptimal temperature and/or relative humidity. Uncontrollable moisture uptake by IMF powders triggers many undesirable phenomena including lowering of glass transition temperature, crystallization of lactose, formation of free fat, undesirable modification of surface composition and morphology, and reduced solubility. Sound understanding of product-process interactions is needed for judicious selection of ingredients and optimization of formulation, processing (e.g., homogenization, evaporation, drying) and storage parameters to produce nutritionally superior IMF powders and ensuring their longer shelf life. In this work, we have systematically reviewed the published works on physicochemical properties of IMF powders and how they are affected by the characteristics of ingredients and parameters used during processing and storage.

Fat, oil, and grease (FOG) deposits yield higher methane than FOG in anaerobic co-digestion with waste activated sludge

The formation of fat, oil, and grease (FOG) deposits in sewers is a global challenge for the maintenance of sewer collection systems. Tons of FOG deposits (FDs) are removed from sewer systems every year and present an opportunity for increased methane production via anaerobic co-digestion with waste activated sludge (WAS) at water resource recovery facilities with existing anaerobic digesters. We hypothesized that FDs have higher biomethane potential than that of FOG (e.g., FOG collected in grease interceptors), because of the reduction of inhibition of long chain fatty acids due to saponification. In this study, substantially enhanced methane production was found in anaerobic co-digestion of WAS with FDs within the substrate to inoculum (S/I) ratio range of 0.25–1.2, and the maximum ultimate methane production (685.7 ± 24.1 mL/gVSadded, at S/I = 0.5) was 4.0 times higher than in the control (with WAS only) after 42 days of incubation. Although the lag phase period was longer in FD co-digestion (S/I = 0.5) than in FOG co-digestion (S/I = 0.5) under the same organic loading (gVS) and two times the COD loading, the daily methane production rate became higher after Day 15 in FD co-digestion. Significantly higher cumulative methane production (10.2%, p < 0.05) was obtained in FD co-digestion than in FOG co-digestion after 42-days. Microbial community analysis revealed higher levels of Geobacter in FD co-digestion, possibly suggesting a role for direct interspecies electron transfer (DIET) between Methanosaeta and Geobacter. This work provides fundamental insights supporting anaerobic co-digestion of FDs with WAS, demonstrating the advantages of FDs compared to FOG as co-substrate for enhanced biomethane recovery.

Exploring the Role of SRC in Extraocular Muscle Fibrosis of the Graves' Ophthalmopathy.

The Graves’ disease is an autoimmune disease highly associated with thyroid cancer. The Graves’ ophthalmopathy (GO) is a special Graves’ disease with inflammatory ophthalmopathy being a typical extrathymic complication. GO is caused by the formation of orbital fat and extraocular muscle fibrosis due to the inflammation of orbital connective tissues. Thus, controlling extraocular muscle fibrosis is critical for the prognosis of GO. The objective of this study is to identify and experimentally validate key genes associated with GO and explore their potential function mechanisms especially on extraocular muscle fibrosis. Specifically, we first created a GO mouse model, and performed RNA sequencing on the extraocular muscles of fibrotic GO mice and controls. SRC was identified as the most significant unstudied differentially expressed gene between GO mice and controls. Thus, we conducted a few in vitro analyses to explore the roles and functions of SRC in GO, for which we selected primary cultured orbital fibroblast (OF) as the in vitro cell line model. It is known that myofibroblast (MFB), which expresses α-SMA, is an important target cell in the process of fibrosis. Our experiment suggests that TGF-β can induce the transformation from OF to MFB, however, the transformation was inhibited by silencing the SRC gene in OF. In addition, we also inhibited TGF-β/Smad, NF-κB, and PI3K/Akt signaling pathways to analyze the interaction between these pathways and SRC. In conclusion, the silence of SRC in OF can inhibit the transformation from OF to MFB, which might be associated with the interaction between SRC and a few pathways such as TGF-β/Smad, NF-κB, and PI3K/Akt.

Discoidin domain receptor 1-deletion ameliorates fibrosis and promotes adipose tissue beiging, brown fat activity, and increased metabolic rate in a mouse model of cardiometabolic disease

ObjectiveDiscoidin domain receptor 1 (DDR1) is a collagen binding receptor tyrosine kinase implicated in atherosclerosis, fibrosis, and cancer. Our previous research showed that DDR1 could regulate smooth muscle cell trans-differentiation, fibrosis and calcification in the vascular system in cardiometabolic disease. This spectrum of activity led us to question whether DDR1 might also regulate adipose tissue fibrosis and remodeling. MethodsWe have used a diet-induced mouse model of cardiometabolic disease to determine whether DDR1 deletion impacts upon adipose tissue remodeling and metabolic dysfunction. Mice were fed a high fat diet (HFD) for 12 weeks, followed by assessment of glucose and insulin tolerance, respiration via indirect calorimetry, and brown fat activity by FDG-PET. ResultsFeeding HFD induced DDR1 expression in white adipose tissue, which correlated with adipose tissue expansion and fibrosis. Ddr1−/− mice fed an HFD had improved glucose tolerance, reduced body fat, and increased brown fat activity and energy expenditure compared to Ddr1+/+ littermate controls. HFD-fed DDR1−/− mice also had reduced fibrosis, smaller adipocytes with multilocular lipid droplets, and increased UCP-1 expression characteristic of beige fat formation in subcutaneous adipose tissue. In vitro, studying C3H10T1/2 cells stimulated to differentiate, DDR1 inhibition caused a shift from white to beige adipocyte differentiation, whereas DDR1 expression was increased with TGFβ-mediated pro-fibrotic differentiation. ConclusionThis study is the first to identify a role for DDR1 as a driver of adipose tissue fibrosis and suppressor of beneficial beige fat formation.

Effects of Fat Tissue on Chronic Muscle Injuries

During aging and certain muscle diseases such as Duchenne Muscular Dystrophy (DMD), muscle mass declines and is being replaced with fat tissue in a process called fatty degeneration. However, it is unclear if intramuscular fat plays an important role in the initiation and/or progression of fatty degeneration. Recent data suggests that when the fat fraction is greater than 0.5, over half of DMD patients are no longer able to walk. Based on these observations we, therefore, hypothesize that an increase in fat could impair muscle regeneration and function in chronic injuries. In young and healthy muscles, satellite stem cells are required for regeneration. Fibro/adipogenic progenitors (FAPs), which can differentiate into fat tissue and produce fibrotic scar tissue during chronic injuries and aging, aid in the healing process of muscle injuries. While beneficial, the exact relationship between FAPs and satellite stem cells during muscle regeneration is unclear. The purpose of this project was to establish a novel mouse model enabling us to conditionally prevent the differentiation of FAPs into adipocytes to determine the functional role of fat. To prevent FAPs from turning into fat, we conditionally deleted Pparγ, the master regulator of adipogenesis, using the Cre‐LoxP system in the mouse (Pparγ cKO). To induce fat formation, I injected 50% Glycerol into the tibialis anterior muscle, which causes muscle fiber loss and replacement with adipocytes. I stained adipocytes with PERILIPIN via immunofluorescence and quantified the amount of fat that was present in Pparγ cKO and control mice to determine if fat formation was indeed repressed after loss of Pparγ. I found a strong reduction in the amount of adipocytes, which have formed 21 days after a Glycerol induced injury in Pparγ cKO compared to control mice, arguing for efficient repression of adipogenesis. I also looked at fibrosis through Sirius Red staining to determine if the decrease in fat cells resulted in an increase of FAPs developing into fibrotic scar tissue. However, I saw no significant difference in fibrotic tissue between control and Pparγ cKO mice, suggesting that the prevention of fat formation does not cause an increase in the presence of fibrotic tissue.Thus, our new mouse model successfully blocks fat formation without increasing fibrotic scar tissue. In the future, this new mouse model will allow us to determine if the prevention of fat in a chronic muscle disease model, such as the mouse model for Duchenne Muscular Dystrophy, will have a positive effect on muscle repair and function.Support or Funding InformationStart‐up grant given to Daniel Kopinke; ASPET SURF Program at the University of Florida funding to Mikayla Quigley

새싹보리 에탄올 추출물을 이용한 항비만 효과 확인

Obesity is caused by a variety of reasons, such as diet, genetics, and environmental factors. Here the effect of Barley sprout extract on the differentiation of 3T3-L1 and the expression of adipogenesis was studied. MTT assay for cell toxicity was performed and found to be non-toxic at 3T3-L1, with a survival rate of 90% or higher in Barley sprout extract at all concentrations. The results of oil red O assay, after inducing differentiation by treating the fat formation with insulin, dexamethasone, and IBMX powder-inducing substances at 3T3-L1, showed that the Barley sprout extract inhibited fat formation. The results of a triglyceride assay for the determination of quantitative inhibition of fat formation showed 42.2% and 45.7% in Barley sprout extracts of 50% and 70%, respectively. Western blot was performed to identify the proteins involved in fat cell suppression, and it was found that there was a concentration-dependent decrease in C/EBPα, PPARγ, and p-ACC proteins. Thus, Barley sprout ethanol extract regulates the expression of protein involved in inhibiting fat cells, thereby reducing the differentiation of fat cells and triglyceride production and indicating that it is effective against obesity.

Lack of UCP1 stimulates fatty liver but mediates UCP1-independent action of beige fat to improve hyperlipidemia in Apoe knockout mice

Brown adipose tissue (BAT) plays a critical role in lipid metabolism and may protect from hyperlipidemia; however, its beneficial effect appears to depend on the ambient temperature of the environment. In this study, we investigated the effects of uncoupling protein 1 (UCP1) deficiency on lipid metabolism, including the pathophysiology of hyperlipidemia, in apolipoprotein E knockout (APOE-KO) mice at a normal (23 °C) and thermoneutral (30 °C) temperature. Unexpectedly, UCP1 deficiency caused improvements in hyperlipidemia, atherosclerosis, and glucose metabolism, regardless of an increase in hepatic lipid deposition, in Ucp1/Apoe double-knockout (DKO) mice fed a high-fat diet at 23 °C, with BAT hyperplasia and robust browning of inguinal white adipose tissue (IWAT) observed. Proteomics and gene expression analyses revealed significant increases in many proteins involved in energy metabolism and strong upregulation of brown/beige adipocyte-related genes and fatty acid metabolism-related genes in browned IWAT, suggesting an induction of beige fat formation and stimulation of lipid metabolism in DKO mice at 23 °C. Conversely, mRNA levels of fatty acid oxidation-related genes decreased in the liver of DKO mice. The favorable phenotypic changes were lost at 30 °C, with BAT whitening and disappearance of IWAT browning, while fatty liver further deteriorated in DKO mice compared with that in APOE-KO mice. Finally, longevity analysis revealed a significant lifespan extension of DKO mice compared with that of APOE-KO mice at 23 °C. Irrespective of the fundamental role of UCP1 thermogenesis, our results highlight the importance of beige fat for the improvement of hyperlipidemia and longevity under the atherogenic status at normal room temperature.

MiR-450a-5p Eliminates MGO-Induced Insulin Resistance via Targeting CREB.

Background and ObjectivesmiR-450a-5p was involved in fat formation, however, its role in insulin resistance remains unclear. This study investigated the effects of miR-450a-5p on endothelial cells, with the aim of finding a potential target for diabetes mellitus.Methods and ResultsHuman umbilical vein endothelial cells (HUVECs) were treated with low-glucose, high-glucose, methylglyoxal (MGO), and insulin alone or in combination with MGO. The expression of miR-450a-5p in treated cells was measured by quantitative real-time polymerase chain reaction (qRT-PCR) assays. The cell activity, migration and fat formation were determined by MTT experiments, Transwell assay and oil red O staining. The expressions of eNOS/AKT pathway-related proteins in cells were assessed by Western blot (WB) analysis. Furthermore, the target gene of miR-450a-5p was analyzed by double-luciferase reporter analysis, and its effects on eNOS/AKT pathway were estimated. We found that the expression of miR-450a-5p was decreased obviously in endothelial cells treated with high-glucose and MGO. In vitro cell experiments showed that MGO could not only promote the activity of endothelial cells, but also accelerate cell migration and fat accumulation, which, however, could be reversed by up-regulation of miR-450a-5p. Moreover, MGO inhibited eNOS/AKT pathway activation and NO release mediated by insulin, and such effects were reversed by up-regulation of miR-450a-5p. Furthermore, CREB was the target gene for miR-450a-5p, had an activation effect on the eNOS/AKT pathway.ConclusionsUp-regulated miR-450a-5p eliminates MGO-induced insulin resistance via targeting CREB, and therefore could be used as a potential target to improve insulin resistance and treat patients with diabetes-related diseases.

Influence of Nanovulin-VRKh on cattle thermoregulation and chemical composition of milk

The current research described the effect of neurotropic and metabolic non-hormonal biologically active medicine Nanovulin-VRKh © on the milk yield amount and the milk quality. Two cow groups were under study: the experimental and the control groups, each including four cows. The results showed that two of the neurotropic and metabolic Nanovulin-VRKh injections made 12 and 24 hours after the insemination did not effect the body thermoregulation of cows. Administration of the Nanovulin-VRKh contributes to stable fat formation in cow milk. Increased content of protein, nonfat milk solids, stable fat formation in milk were due to Nanovulin-VRKh administration. It was also established that, in the milk of experimental animals were administered the Nanovulin-VRKh, the pronounced effect of the drug on the protein, fat and nonfat milk solids content was observed, and the prolonged effect on these indices was reported during the fourth milking. Introduction of Cuprum aqua-chelate into the drug did not has toxic effect on the animal body and therefore would not effect the human health through the dairy products.

Tetramethylpyrazine/Ligustrazine Can Improve the Survival Rate of Adipose-Derived Stem Cell Transplantation.

We aimed to study the effect of tetramethylpyrazine/ligustrazine (TMP) on the survival rate of adipose-derived stem cell (ADSC) transplantation. Human ADSCs were cultured and subcultured. Detection of cell growth was performed using CCK8 kit. A total of 12 BALB/c nude mice including 4 groups (group 1: ADSC-hyaluronic acid [HA] + phosphate-buffered saline [PBS]; group 2: ADSC-HA + TMP injection; group 3: ADSC-HA + TMP soaking; group 4: ADSC-HA + TMP injection + TMP soaking) were used for the animal experiments. Furthermore, hematoxylin-eosin staining and oil red O staining were conducted for the frozen section from the animal tissues. Besides, RNA was extracted from the samples, and reverse transcriptase-polymerase chain reaction experiment was performed. At last, samples were detected using transmission electron microscope. Tetramethylpyrazine/ligustrazine resulted in significant increase for cell proliferation on the seventh day. It was easier to promote the growth of adipose cell after injection and soaking of TMP. Hematoxylin-eosin staining and oil red O stain showed that injection and soaking of TMP could significantly increase the size of fat. The relative expression of peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, and Alu in group 4 was significantly higher than that in other groups. Tetramethylpyrazine/ligustrazine can improve the survival rate of ADSC transplantation. The possible mechanisms of it may be that TMP induces the expression of transcription factor associated with fat formation including peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, and Alu and then promotes the growth of adipose cell.

The increase of atherogenic index on fatty acids composition as a consequence of trans fat acids reduction in industrialized foods: the Brazilian scenery

Abstract The use of fats with a low melting point is attractive to the food industry, as it contributes to improving the texture, color and stability characteristics of the food. These fats are obtained from vegetable oils through some processes such as hydrogenation or interesterification. However, the partial hydrogenation process leads to the formation of trans fat. In several countries, actions have been taken to eliminate the presence of elaidic acid, a trans fatty acid (C18: 1t) from processed foods. This trans fatty acid and palmitic acid, a common saturated fatty acid (C16: 0) are proven to be atherogenic. The aim of this work was to evaluate the composition of fatty acids of 39 types of commercialized foods in Brazil, including cookies, snacks, wafers, instant noodles, frozen sandwiches and pizzas, mixtures for food preparation, microwave popcorn, margarines, spreadable cheeses and pastry dough. The lipids were extracted and their Fatty Acid Methyl Esters (FAMEs) identified by Gas-Chromatography (GC). The fatty acids found in greater quantity were oleic, linoleic and palmitic acids; whereas the trans fatty acids were detected in 51.3% of the samples. On the other hand, when trans fast were reduced in some foods, it could be observed increases in the palmitic acid (C16:0) content. This high content of palmitic acid is justified by the addition of palm oil and its derivatives, which can be used in interesterified oil mixtures or can be directly used in industrialized food formulations, even without interesterification. Governments and organizations in favor of human health should be aware that the use of dietary fatty acids which compromise the atherogenic index is not a healthy alternative. Consumers should therefore be alerted to the risk of consuming foods containing these fats until the food industry is banned from using them or finds healthier alternatives for making food.

Evaluation of Trans Fat in Vermicelli by Fourier Transform Infrared Spectroscopy in Combination with Chemometric Technique

Since there is limited knowledge about trans fat levels in snack foods available in Pakistan. This study aimed to determine trans fat content in fried vermicelli (a common snack food). It is prepared in partially hydrogenated oil (ghee), which is the main cause of trans fat formation. Twenty-one fried vermicelli samples were collected from different local shops of Hyderabad, Pakistan and subjected to oil extraction by using Soxhlet method. Partial least square regression model was developed to quantify trans fats in fried vermicelli using FTIR spectroscopy. Total oil content in fried vermicelli ranged between 17.28- 32.99%. FTIR results revealed that fried vermicelli showed trans fats in between 7.3-20.9% in extracted oil, whereas total trans fat in food was ranged at 1.3-5.9%. The FTIR data of trans fat was compared with GC-MS data and found comparable results (pandgt;0.05). Presence of high trans fat in fried vermicelli is an alarming issue for the health of consumers.

Evaluation of Trans Fat in Vermicelli by Fourier Transform Infrared Spectroscopy in Combination with Chemometric Technique

Since there is limited knowledge about trans fat levels in snack foods available in Pakistan. This study aimed to determine trans fat content in fried vermicelli (a common snack food). It is prepared in partially hydrogenated oil (ghee), which is the main cause of trans fat formation. Twenty-one fried vermicelli samples were collected from different local shops of Hyderabad, Pakistan and subjected to oil extraction by using Soxhlet method. Partial least square regression model was developed to quantify trans fats in fried vermicelli using FTIR spectroscopy. Total oil content in fried vermicelli ranged between 17.28- 32.99%. FTIR results revealed that fried vermicelli showed trans fats in between 7.3-20.9% in extracted oil, whereas total trans fat in food was ranged at 1.3-5.9%. The FTIR data of trans fat was compared with GC-MS data and found comparable results (pandgt;0.05). Presence of high trans fat in fried vermicelli is an alarming issue for the health of consumers.

Molecular characterization of fibroblast growth factor-16 and its role in promoting the differentiation of intramuscular preadipocytes in goat

Fat metabolism is an important and complex biochemical reaction in vivo and is regulated by many factors. Recently, the findings on high expression of fibroblast growth factor-16 (FGF16) in brown adipose tissue have led to an interest in exploring its role in lipogenesis and lipid metabolism. The study cloned the goat’s FGF16 gene 624 bp long, including the complete open reading frame that encodes 207 amino acids. We found that FGF16 expression is highest in goat kidneys and hearts, followed by subcutaneous fat and triceps. Moreover, the expression of FGF16 reached its peak on the 2nd day of adipocyte differentiation (P < 0.01) and then decreased significantly. We used overexpression and interference to study the function of FGF16 gene in goat intramuscular preadipocytes. Silencing of FGF16 decreased adipocytes lipid droplet aggregation and triglyceride synthesis. This is in contrast to the situation where FGF16 is overexpressed. Furthermore, knockdown of FGF16 also caused down-regulated expression of genes associated with adipocyte differentiation including CCAAT enhancer-binding protein beta (P < 0.01), fatty acid-binding protein-2 (P < 0.01) and sterol regulatory element binding protein-1 (P < 0.05), but the preadipocyte factor-1 was up-regulated. At the same time, the genes adipose triglyceride lipase (P < 0.01) and hormone-sensitive lipase (P < 0.05) associated with triglyceride breakdown were highly expressed. Next, we locked the fibroblast growth factor receptor-4 (FGFR4) through the protein interaction network and interfering with FGF16 to significantly reduce FGFR4 expression. It was found that the expression profile of FGFR4 in adipocyte differentiation was highly similar to that of FGF16. Overexpression and interference methods confirmed that FGFR4 and FGF16 have the same promoting function in adipocyte differentiation. Finally, using co-transfection technology, pc-FGF16 and siRNA-FGFR4, siRNA2-FGF16 and siRNA-FGFR4 were combined to treat adipocytes separately. It was found that in the case of overexpression of FGF16, cell lipid secretion and triglyceride synthesis showed a trend of first increase and then decrease with increasing interference concentration. In the case of interference with FGF16, lipid secretion and triglyceride synthesis showed a downward trend with the increase of interference concentration. These findings illustrated that FGF16 mediates adipocyte differentiation via receptor FGFR4 expression and contributed to further study of the functional role of FGF16 in goat fat formation.

P2Y2 Nucleotide Receptor Is a Regulator of the Formation of Cardiac Adipose Tissue and Its Fat-Associated Lymphoid Clusters.

The formation of pericardial adipose tissue (PAT) and its regulatory function in cardiac inflammation are not well understood. We investigated the potential role of the ubiquitous ATP/UTP nucleotide receptor P2Y2 in the PAT by using P2Y2-null mice. We observed that P2Y2-null mice displayed a lower mass of PAT and a reduced density of its fat-associated lymphoid clusters (FALCs) and, more particularly, B cells. Loss of P2Y2 receptor in pericardial preadipocytes decreased their adipogenic differentiation and maturation abilities in vitro. Gene profiling identified P2Y2 target genes in PAT linked to immunomodulation. These data led to the identification of an increase of M2c anti-inflammatory macrophages correlated with increased apoptosis of B lymphocytes in P2Y2-null pericardial fat. In addition, follicular helper T cells, which contribute to B cell expansion in germinal centers, were dramatically decreased. The effect of P2Y2 loss was also investigated after ischemia-mediated expansion of FALCs in a model of myocardial infarct. Loss of P2Y2 led to reduced expansion of B and neutrophil populations in these clusters, whereas density of M2c anti-inflammatory macrophages was increased. Our study defines the P2Y2 nucleotide receptor as a regulator of the formation and inflammatory status of pericardial fat. The P2Y2 receptor could represent a therapeutic target in the regulation of PAT function before and during cardiac ischemia.

Myristoleic acid produced by enterococci reduces obesity through brown adipose tissue activation

ObjectiveDietary fibre has beneficial effects on energy metabolism, and the majority of studies have focused on short-chain fatty acids produced by gut microbiota. Ginseng has been reported to aid in...

Preadipocyte factor 1 regulates adipose tissue browning via TNF-α-converting enzyme-mediated cleavage

BackgroundIncreasing adaptive thermogenesis in adipose tissue may be a potential therapeutic target for overcoming obesity and obesity-related disorders. Preadipocyte factor 1 (Pref-1), a preadipocyte secreted protein, plays an inhibitory role in adipogenic differentiation. However, the role of Pref-1 in adipose tissue browning remains unknown. We investigated whether Pref-1 regulates thermogenic program and beige fat biogenesis. MethodsPref-1 expression levels were examined in inguinal white adipose tissue (iWAT) and differentiated 3T3-L1 adipocytes in thermogenic conditions induced by cold exposure or a beta-adrenergic stimulus (CL316,243). Overexpression and knockdown studies were performed both in vivo and in vitro to clarify the role of Pref-1 in iWAT browning. ResultsCold exposure or CL316,243 induced a thermogenic program in adipose tissue of C57BL/6N mice and in 3T3-L1 adipocytes. Notably, Pref-1 levels were down-regulated in iWAT and adipocytes under these conditions. Overexpressing Pref-1 showed reduced thermogenic gene expressions in response to CL316,243 treatment, whereas depletion of Pref-1 augmented thermogenic program in 3T3-L1 adipocytes. Correspondingly, treating C57BL/6N mice with Pref-1 resulted in reduced expression of thermogenic and beige fat markers, a reduced rate of oxygen consumption, blunting of UCP1 expression and beige fat formation in iWAT in response to cold exposure or CL316,243 injection compared to the untreated mice. The opposite phenotype was observed in mice with inducible fat-specific knock-out of Pref-1. Mechanistically, these effects were regulated by modulation of TNF-α-converting enzyme activity and Pref-1 cleavage. ConclusionOur findings establish a novel role of Pref-1 that regulates adaptive thermogenesis. This offers a unique target for improving energy homeostasis and treating obesity.

The Power of LC-MS Based Multiomics: Exploring Adipogenic Differentiation of Human Mesenchymal Stem/Stromal Cells.

The molecular study of fat cell development in the human body is essential for our understanding of obesity and related diseases. Mesenchymal stem/stromal cells (MSC) are the ideal source to study fat formation as they are the progenitors of adipocytes. In this work, we used human MSCs, received from surgery waste, and differentiated them into fat adipocytes. The combination of several layers of information coming from lipidomics, metabolomics and proteomics enabled network analysis of the biochemical pathways in adipogenesis. Simultaneous analysis of metabolites, lipids, and proteins in cell culture is challenging due to the compound’s chemical difference, so most studies involve separate analysis with unimolecular strategies. In this study, we employed a multimolecular approach using a two–phase extraction to monitor the crosstalk between lipid metabolism and protein-based signaling in a single sample (~105 cells). We developed an innovative analytical workflow including standardization with in-house produced 13C isotopically labeled compounds, hyphenated high-end mass spectrometry (high-resolution Orbitrap MS), and chromatography (HILIC, RP) for simultaneous untargeted screening and targeted quantification. Metabolite and lipid concentrations ranged over three to four orders of magnitude and were detected down to the low fmol (absolute on column) level. Biological validation and data interpretation of the multiomics workflow was performed based on proteomics network reconstruction, metabolic modelling (MetaboAnalyst 4.0), and pathway analysis (OmicsNet). Comparing MSCs and adipocytes, we observed significant regulation of different metabolites and lipids such as triglycerides, gangliosides, and carnitine with 113 fully reprogrammed pathways. The observed changes are in accordance with literature findings dealing with adipogenic differentiation of MSC. These results are a proof of principle for the power of multimolecular extraction combined with orthogonal LC-MS assays and network construction. Considering the analytical and biological validation performed in this study, we conclude that the proposed multiomics workflow is ideally suited for comprehensive follow-up studies on adipogenesis and is fit for purpose for different applications with a high potential to understand the complex pathophysiology of diseases.