Molecular Regulation of Adipogenesis and Potential Anti-Adipogenic Bioactive Molecules

FABP4 in Gestational Diabetes-Association between Mothers and Offspring

Fetuses exposed to gestational diabetes mellitus (GDM) have a higher risk of abnormal glucose homeostasis in later life. The molecular mechanisms of this phenomenon are still not fully understood. Fatty acid binding protein 4 (FABP4) appears to be one of the most probable candidates involved in the pathophysiology of GDM. The main aim of the study was to investigate whether umbilical cord serum FABP4 concentrations are altered in term neonates born to GDM mothers. Two groups of subjects were selected—28 healthy controls and 26 patients with GDM. FABP4, leptin, and ghrelin concentrations in the umbilical cord serum, maternal serum, and maternal urine were determined via an enzyme-linked immunosorbent assay. The umbilical cord serum FABP4 levels were higher in the GDM offspring and were directly associated with the maternal serum FABP4 and leptin levels, as well as the prepregnancy body mass index (BMI) and the BMI at and after delivery; however, they correlated negatively with birth weight and lipid parameters. In the multiple linear regression models, the umbilical cord serum FABP4 concentrations depended positively on the maternal serum FABP4 and negatively on the umbilical cord serum ghrelin levels and the high-density lipoprotein cholesterol. There are many maternal variables that can affect the level of FABP4 in the umbilical cord serum, thus, their evaluation requires further investigation.

Effect of Enzymatic Treatment of Chrysanthemum indicum Linné Extracts on Lipid Accumulation and Adipogenesis in High-Fat-Diet-Induced Obese Male Mice

Enzyme treatment of the foods and herbs has been used to improve the absorption rate the efficiency of plant extracts by converting the glycosides of the plant into aglycones. In this study, we examined the obesity-inhibitory effect of Chrysanthemum indicum Linné (CI) treated with enzymes such as viscozyme and tannase, which are highly efficient in converting glycosides to aglycones and then compared with untreated CI extract. The enzyme-treated CI ethanol extract (CIVT) was administered orally at various doses for 7 weeks in the high fat diet (HFD)-fed male mice. CIVT administration reduced the body weights, the food efficiency and the serum levels of lipid metabolism-related biomarkers, such as triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and leptin in the dose-dependent manner but not those high-density lipoprotein cholesterol (HDL-c) and adiponectin. CIVT also reduced considerably the total lipid amount in the liver and the size of adipocytes in the epididymal white adipose tissue (eWAT). CIVT effectively downregulated the adipogenesis-related transcription factors such as peroxisome proliferation activated receptor (PPAR)-γ and CCAAT/enhancer binding protein-α (C/EBP-α) but up-regulated PPAR-α, in the liver and eWAT. In addition, when compared to the enzyme-untreated CI 50% ethanol extract (CIEE), CIVT enhanced the reduction of body weight and lipid accumulation. Moreover, the viscozyme and tannase treatment of CI increased the flavonoid contents of the aglycone form. Therefore, our results support that the enzymatic treatment induced the production of aglycones for potentially suppressing the adipogenesis and lipid accumulation in HFD-fed mice. It suggests that CIVT might be an effective candidate for attenuating the over-weight and its related diseases.

Neurosecretory Protein GL Induces Fat Accumulation in Chicks

We recently found a previously unidentified cDNA in chicken hypothalamus which encodes the precursor for neurosecretory protein GL (NPGL). A previous study showed that intracerebroventricular (i.c.v.) infusion of NPGL caused body mass gain in chicks. However, it was not clear which part(s) of the body gained mass. In the present study, we investigated which tissues increased in mass after chronic i.c.v. infusion of NPGL in chicks. We found that NPGL increased the masses of the liver, abdominal fat, and subcutaneous fat, while NPGL did not affect the masses of muscles, including pectoralis major, pectoralis minor, and biceps femoris. Oil Red O staining revealed that fat deposition had occurred in the liver. In addition, the size of the lipid droplets in the abdominal fat increased. Furthermore, we found an upregulation of lipogenesis and downregulation of lipolysis in the abdominal fat, but not in the liver. These results indicate that NPGL is involved in fat storage in chicks.

Ginsenoside Rg2 inhibits adipogenesis in 3T3-L1 preadipocytes and suppresses obesity in high-fat-diet-induced obese mice through the AMPK pathway

Rg2-induced activation of AMPK reduced the expression of adipogenic transcription factors, and regulated the lipogenic and lipolysis genes, thus inhibiting adipogenesis.

Synergistic Inhibitory Effects of Acacetin and 11 Other Flavonoids Isolated from Artemisia sacrorum on Lipid Accumulation in 3T3-L1 Cells

Artemisia sacrorum Ledeb., a Compositae forage plant in China, has been found to have an inhibitory effect on lipid accumulation. We selected 12 flavonoids, which we had isolated from A. sacrorum and had the potential to inhibit lipid accumulation in the literature or in our preliminary experiments, and grouped them into 11 compound combinations; we investigated their synergistic inhibitory effects on lipid accumulation in 3T3-L1 cells. In screening experiments, Oil-Red O staining, triglyceride levels, and lipid accumulation levels all indicated that combined acacetin and apigenin displayed a significant synergistic inhibitory effect and the best repeatability. Subsequent research showed that this combination could synergistically promote the phosphorylations of AMPK and ACC. Furthermore, to a different extent, that combination had significant synergistic inhibitory effects on various genes or proteins related to adipogenesis and lipogenesis. Thus, that combination could significantly reduce triglyceride levels and lipid accumulation compared with acacetin or apigenin acting alone.

Anti-obesity effects of kaempferol by inhibiting adipogenesis and increasing lipolysis in 3T3-L1 cells

Kaempferol is a natural flavonoid widely found in fruits, vegetables, and tea. Kaempferol possesses beneficial biological properties such as anti-inflammatory and antioxidant activities. Positive energy balance during obesity correlates with a pro-inflammatory chronic state. In this context, we hypothesized that kaempferol might promote anti-obesity effects by modulating adipogenesis and lipolytic pathways. Adipocyte viability at 24, 48, and 72 h was measured by an ATP-based assay. Pre-adipocytes (day 0) or mature adipocytes (day 12) were treated with 60 μM kaempferol until day 21 to evaluate its potential anti-adipogenic and lipolytic effect, respectively. Total lipid accumulation was assessed using Oil Red O staining assay. Gene expression was measured by RT-qPCR to evaluate the effect of kaempferol on adipogenesis and lipolysis gene expression. Our results showed a dose-dependent effect of kaempferol treatment on cell viability promoting cell death at higher than 60 μM concentration. Pre-adipocytes stimulation by 60 μM kaempferol resulted in 62% adipogenesis inhibition whereas in mature adipocytes, it reduced 39% intracellular lipid accumulation. Also, 60 μM kaempferol treatment decreased Cebpa mRNA expression when compared to control cells. In contrast, Pnpla2 and Lipe gene expression were upregulated in 3T3-L1 cells incubated with 60 μM kaempferol. In summary, our results showed that kaempferol modulates adipogenic differentiation in 3T3-L1 cells by promoting downregulation of Cebpa gene expression and decreasing lipid accumulation in mature adipocytes by its positive effects on Pnpla2 and Lipe mRNA levels. Kaempferol might display an anti-obesity effect.

De novo sequencing and transcriptome assembly of Arisaema heterophyllum Blume and identification of genes involved in isoflavonoid biosynthesis

Arisaema heterophyllum Blume (AhBl) is one of the valued medicinal plants. However, its genetic information is limited, which impedes further studies of this valuable resource. To investigate the genes involved in the isoflavonoid biosynthesis, we deeply performed transcriptome sequencing for AhBl. An average of 10.98 Gb clean reads were obtained based on root, tuber and leaf tissues, and 109,937 unigenes were yielded after de novo assembly. In total, 72,287 of those unigenes were annotated in at least one public database. The numbers of expressed unigenes in each tissue were 35,686, 43,363 and 47,783, respectively. The overall expression levels of transcripts in leaf were higher than those in root and tuber. Differentially expressed genes analysis indicated that a total of 12,448 shared unigenes were detected in all three tissues, 10,215 of which were higher expressed in tuber than that in root and leaf. Besides, 87 candidate unigenes that encode for enzymes involved in biosynthesis of isoflavonoid were identified and analyzed, and some key enzyme genes were experimentally validated by quantitative Real-Time PCR (qRT-PCR). This study provides a unique dataset for the systematic analysis of AhBl functional genes and expression characteristics, and facilitates the future study of the pharmacological mechanism of AhBl.

Fatty Acid-Binding Protein 4-An "Inauspicious" Adipokine-In Serum and Urine of Post-Partum Women with Excessive Gestational Weight Gain and Gestational Diabetes Mellitus

The exact roles of adipokines in the pathogenesis of type 2 diabetes and obesity are still unclear. The aim of the study was to evaluate fatty acid binding protein 4 (FABP4) concentrations in the serum and urine of women with excessive gestational weight gain (EGWG) and gestational diabetes mellitus (GDM) in the early post-partum period, with reference to their laboratory test results, body composition, and hydration status. The study subjects were divided into three groups: 24 healthy controls, 24 mothers with EGWG, and 22 GDM patients. Maternal body composition and hydration status were evaluated by the bioelectrical impedance analysis (BIA) method. Concentrations of FABP4, leptin, and ghrelin were determined via enzyme-linked immunosorbent assay (ELISA). Healthy women were characterized by the lowest serum leptin concentrations and by a negative correlation between the serum and urine FABP4 levels. Serum FABP4 levels were the highest in the GDM group. Serum FABP4 and leptin concentrations correlated positively in the GDM group. The EGWG group had the highest degree of BIA disturbances in the early puerperium and positive correlations between the urine FABP4 and serum leptin and ghrelin concentrations. The physiological and pathological significance of these findings requires further elucidation.

Prenatal exposure to perfluoroalkyl substances and adipocytokines: the HOME Study

OBJECTIVE

Gestational perfluoroalkyl substances exposure has been associated with decreased birthweight. We determined if gestational perfluoroalkyl substances exposure was associated with fetal metabolic markers using data from the HOME Study, a prospective birth cohort of pregnant women and their children in Cincinnati, Ohio.

METHODS

Maternal serum concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid, and perfluorohexane sulfonic acid were quantified. We measured neonatal adipocytokine (leptin and adiponectin) concentrations in umbilical cord serum, and estimated percent differences with a 2-fold increase in maternal perfluoroalkyl substances concentrations among 230 mother-infant pairs.

RESULTS

Median maternal serum PFOA and PFOS concentrations were 5.6 ng/mL and 14 ng/mL, respectively. Leptin was positively correlated with infant birthweight (p < 0.001). There were no statistically significant associations between maternal perfluoroalkyl substances and neonatal adipocytokine concentrations; each 2-fold increase in PFOA was associated with a non-significant increase in leptin (5%; 95% CI: -10, 22) and adiponectin (7%; 95% CI: -4, 19).

CONCLUSION

Despite known associations with reduced birthweight, gestational serum perfluoroalkyl substances concentrations were not associated with neonatal adipocytokine concentrations. Further exploration of pathways of perfluoroalkyl substances associated changes in birthweight may help identify biomarkers that could be used to identify at-risk populations and develop interventions.

Pentacyclic triterpenes: New tools to fight metabolic syndrome

BACKGROUND

Metabolic syndrome is a combination of dysregulated cardiometabolic risk factors characterized by dyslipidemia, impaired glucose tolerance, insulin resistance, inflammation, obesity as well as hypertension. These factors are tied to the increased risk for type-II diabetes and cardiovascular diseases including myocardial infarction in patients with metabolic syndrome.

PURPOSE

To review the proposed molecular mechanisms of pentacyclic triterpenes for their potential use in the metabolic syndrome.

METHODS

PubMed, Science Direct, and Google Scholar database were searched from commencement to April 2018. Following keywords were searched in the databases with varying combinations: "metabolic syndrome", "pentacyclic triterpenes", "transcription factors", "protein kinase", "lipogenesis", "adipogenesis", "lipolysis", "fatty acids", "gluconeogenesis", "cardiovascular", "mitochondria", "oxidative stress", "pancreas", "hepatic cells", "skeletal muscle", "3T3-L1", "C2C12", "obesity", "inflammation", "insulin resistance", "glucose uptake", "clinical studies" and "bioavailability".

RESULTS

Pentacyclic triterpenes, such as asiatic acid, ursolic acid, oleanolic acid, 18β-glycyrrhetinic acid, α,β-amyrin, celastrol, carbenoxolone, corosolic acid, maslinic acid, bardoxolone methyl and lupeol downregulate several metabolic syndrome components by regulating transcription factors, protein kinases and enzyme involved in the adipogenesis, lipolysis, fatty acid oxidation, insulin resistance, mitochondria biogenesis, gluconeogenesis, oxidative stress and inflammation.

CONCLUSION

In vitro and in vivo studies suggests that pentacyclic triterpenes effectively downregulate various factors related to metabolic syndrome. These phytochemicals may serve as promising candidates for clinical trials for the management of metabolic syndrome.

MicroRNA-142a-3p promotes the differentiation of 3T3-L1 preadipocytes by targeting high-mobility group AT-hook 1

BACKGROUND

Obesity is characterized by the excess accumulation of adipose tissues, mainly composed of adipocytes. The differentiation of adipocytes is one of the major events in the process of adipogenesis. Among various adipogenic transcription factors, CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferators-activated receptor γ (PPARγ) have been identified as essential regulators of adipocyte differentiation.

METHODS

RT-qPCR assay was conducted to detect the expression of microRNA-142a-3p (miR-142a-3p), high-mobility group AT-hook 1 (HMGA1) mRNA, C/EBPα mRNA, and PPARγ mRNA. Western blot assay was performed to measure the protein levels of HMGA1, C/EBPα and PPARγ. Bioinformatics analysis and luciferase reporter assay were carried out to explore the interaction between miR-142a-3p and HMGA1.

RESULTS

miR-142a-3p expression was notably increased and HMGA1 expression was markedly reduced during 3T3-L1 preadipocyte differentiation. Functional analysis revealed that miR-142a-3p overexpression promoted 3T3-L1 preadipocyte differentiation. Further investigations on molecular mechanisms showed that HMGA1 was a target of miR-142a-3p in 3T3-L1 preadipocytes. Moreover, the knockdown of HMGA1 induced 3T3-L1 preadipocyte differentiation. Additionally, HMGA1 silencing abolished miR-142a-3p deficiency-mediated inhibitory effect on 3T3-L1 preadipocyte differentiation.

CONCLUSION

MiR-142a-3p overexpression facilitated 3T3-L1 preadipocyte differentiation by targeting HMGA1, highlighting the importance of miR-142a-3p, HMGA1 and the miR-142a-3p/HMGA1 axis in adipogenesis.

Fruit and vegetable consumption among adults in Namibia: analysis of a nationally representative population

Background: Prevalence of F&V consumption in Namibia is not known. In this study we aimed to address this gap by using nationally representative data with the objectives of measuring the prevalence of adequate F&V consumption among adult men and women and their socio demographic determinants. Methods: This study is based on data from Namibia Demographic and Health Survey (NDHS2013). Sample population were 14 185 men and women aged between 15 and 49 years.Amount of fruit and vegetable consumption was measured by self-reported frequencies and was defined as adequate (at least 5 servings/day) according to World Health Organization (WHO)guidelines. Results: Overall, only 4.3% (3.8-4.9%) of the men and women reported consuming at least 5 servings of F&V a day, with the percentage being slightly higher among women (4.8%,95% CI=3.7-6.2) compared with men (4.2%, 95% CI=3.6-4.8). In the multivariable analysis,education level and household wealth status appeared to be the only factors associated with adequate F&V intake. Men and women who had primary level education had higher odds of eating at least 5 servings of F&V a day compared with those who had no education. Regarding wealth status, men and women from non-poor households had respectively 2.13 times(OR=2.13, 95% CI=1.01-4.48) and 2.2 times (OR=2.19, 95% CI=1.56-3.38) higher odds of eating at least 5 servings of F&V a day. Conclusion: Only a small proportion of the men and women consumed adequate amount of F&V on daily basis. Having primary level education and non-poor household wealth status were positively associated with adequate amount of F&V intake.

Ginger Extract Ameliorates Obesity and Inflammation via Regulating MicroRNA-21/132 Expression and AMPK Activation in White Adipose Tissue

Ginger is a plant whose rhizome is used as a spice or folk medicine. We aimed to investigate the effect of ginger root extract on obesity and inflammation in rats fed a high-fat diet. Sprague-Dawley rats were divided into three groups and fed either a 45% high-fat diet (HF), HF + hot-water extract of ginger (WEG; 8 g/kg diet), or HF + high-hydrostatic pressure extract of ginger (HPG; 8 g/kg diet) for 10 weeks. The HPG group had lower body weight and white adipose tissue (WAT) mass compared to the HF group. Serum and hepatic lipid levels of HPG group were lower, while fecal lipid excretion of the HPG group was higher than that of the HF group. In the WAT of the WEG and HPG groups, mRNA levels of adipogenic genes were lower than those of the HF group. Moreover, HPG group had lower mRNA levels of pro-inflammatory cytokines than did the HF group. MicroRNA (miR)-21 expression was down-regulated by both WEG and HPG. Additionally, miR-132 expression was down-regulated by HPG. The adenosine monophosphate-activated protein kinase (AMPK) activity of HPG group was greater than that of the HF group. HPG may have beneficial effects on obesity and inflammation, partially mediated by regulation of miR-21/132 expression and AMPK activation in WAT.

Adipogenic potential of perivascular adipose tissue preadipocytes is improved by coculture with primary adipocytes

Perivascular adipose tissue (PVAT) has the capacity to secrete vasoactive mediators with the potential to regulate vascular function. Given its location adjacent to the vasculature, PVAT dysfunction may be part of the pathophysiology of cardiovascular diseases. To study the mechanisms of PVAT dysfunction, several adipogenic models have been proposed. However, these approaches do not adequately reflect PVAT adipocyte phenotypes variability that depends on their anatomical location. Despite PVAT importance in modulating vascular function, to date, there is not a depot-specific adipogenic model for PVAT adipocytes. We present a model that uses coculturing of PVAT stromal vascular fraction derived preadipocytes with primary adipocytes isolated from the same PVAT. Preadipocytes were isolated from thoracic aorta PVAT and mesenteric resistance artery PVAT (mPVAT). Upon confluency, cells were induced to differentiate for 7 and 14 days using a standard protocol (SP) or standard protocol cocultured with primary adipocytes isolated from the same adipose depots (SPA) for 96, 120, and 144 h. SPA reduced the time for differentiation of stromal vascular fraction derived preadipocytes and increased their capacity to store lipids compared with SP as indicated by lipid accumulation, lipolytic responses, gene marker profile expression, and adiponectin secretion. The coculture system improved adipogenesis efficiency by enhancing lipid accumulation and reducing the time of induction, therefore, is a more efficient method compared to SP alone.

Development of an In Vitro Screening Platform for the Identification of Partial PPARγ Agonists as a Source for Antidiabetic Lead Compounds

Type 2 diabetes (T2D) is a metabolic disorder where insulin-sensitive tissues show reduced sensitivity towards insulin and a decreased glucose uptake (GU), which leads to hyperglycaemia. Peroxisome proliferator-activated receptor (PPAR)γ plays an important role in lipid and glucose homeostasis and is one of the targets in the discovery of drugs against T2D. Activation of PPARγ by agonists leads to a conformational change in the ligand-binding domain, a process that alters the transcription of several target genes involved in glucose and lipid metabolism. Depending on the ligands, they can induce different sets of genes that depends of their recruitment of coactivators. The activation of PPARγ by full agonists such as the thiazolidinediones leads to improved insulin sensitivity but also to severe side effects probably due to their behavior as full agonists. Partial PPARγ agonists are compounds with diminished agonist efficacy compared to full agonist that may exhibit the same antidiabetic effect as full agonists without inducing the same magnitude of side effects. In this review, we describe a screening platform for the identification of partial PPARγ agonists from plant extracts that could be promising lead compounds for the development of antidiabetic drugs. The screening platform includes a series of in vitro bioassays, such as GU in adipocytes, PPARγ-mediated transactivation, adipocyte differentiation and gene expression as well as in silico docking for partial PPARγ agonism.

The effects of phenolic glycosides from Betula platyphylla var. japonica on adipocyte differentiation and mature adipocyte metabolism

Betula platyphylla var. japonica (Betulaceae) has been used traditionally in Asian countries for the treatment of inflammatory diseases. A recent study has reported a phenolic compound, platyphylloside from B. platyphylla, that shows inhibition on adipocyte differentiation and induces lipolysis in 3T3-L1 cells. Based on this finding, we conducted phytochemical analysis of the EtOH extract of the bark of B. platyphylla var. japonica, which resulted in the isolation of phenolic glycosides (1–4). Treatment of the isolated compounds (1–4) during adipocyte differentiation of 3T3-L1 mouse adipocytes resulted in dose-dependent inhibition of adipogenesis. In mature adipocytes, arylbutanoid glycosides (2–4) induced lipolysis related genes HSL and ATGL, whereas catechin glycoside (1) had no effect. Additionally, arylbutanoid glycosides (2–4) also induced GLUT4 and adiponectin mRNA expression, indicating improvement in insulin signaling. This suggests that the isolates from B. platyphylla var. japonica exert benefial effects in regulation of adipocyte differentiation as well as adipocyte metabolism.

Silencing LAIR-1 in human THP-1 macrophage increases foam cell formation by modulating PPARγ and M2 polarization

Formation of macrophage-derived foam cells may mark the initial stages of atherosclerosis. We investigated the association between the expression of the leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1) in macrophages and foam cell formation. A foam cell model was established by incubating THP-1-derived macrophages and bone marrow macrophages (BMMs) with oxidized low-density lipoprotein (ox-LDL). The role of LAIR-1 in foam cell formation was evaluated via Oil Red O staining and Dil-ox-LDL fluorescence intensities. Peroxisome proliferator-activated receptor gamma (PPARγ), cholesterol metabolism-related genes, and the role of LAIR-1 in activating classically activated (M1) and alternatively activated (M2) macrophages were evaluated by qPCR. Additionally, activation of protein-tyrosine phosphatase-1 (SHP-1) and cAMP-response element binding protein (CREB) were detected by western blotting. Results indicated that silencing LAIR-1 in macrophages modulated the SHP-1/CREB/PPARγ pathway, thereby promoting M2 macrophage polarization and increasing foam cell formation. Therefore, Inhibition of LAIR-1 in macrophages may promote foam cell formation and atherosclerosis.

Differential Effects of High Sugar, High Lard or a Combination of Both on Nutritional, Hormonal and Cardiovascular Metabolic Profiles of Rodents

BACKGROUND

Dietary interventions in rodents can induce an excess of adipose tissue and metabolic disorders that resemble human obesity. Nevertheless, these approaches are not standardized, and the phenotypes may vary distinctly among studies. The aim of this study was to investigate the effects of different dietary interventions on nutritional, metabolic, biochemical, hormonal, and cardiovascular profiles, as well as to add to development and characterization of an experimental model of obesity.

METHODS

Male Wistar rats were randomized into four groups: control diet (C), high-sugar (HS), high-fat (HF), or high-sugar and high-fat (HFHS). Weekly measurements of body weight, adiposity, area under the curve (AUC) for glucose, blood pressure (BP) and serum triglycerides, total cholesterol level, and leptin were performed.

RESULTS

HF and HFHS models were led to obesity by increases in adipose tissue deposition and the adiposity index. All hypercaloric diets presented systolic BP increases. In addition, the AUC for glucose was greater in HF and HFHS than in C, and only the HF group presented hyperleptinemia.

CONCLUSIONS

HF and HFHS diet approaches promote obesity and comorbidities, and thus represent a useful tool for studying human obesity-related disorders. By contrast, the HS model did not prove to be a good model of obesity.

The fruits of Gleditsia sinensis Lam. inhibits adipogenesis through modulation of mitotic clonal expansion and STAT3 activation in 3T3-L1 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Gleditsia sinensis Lam. (G. sinensis) has been used in Oriental medicine for tumor, thrombosis, inflammation-related disease, and obesity.

AIM OF THE STUDY

The pharmacological inhibitory effects of fruits of G. sinensis (GFE) on hyperlipidemia have been reported, but its inhibitory effects on adipogenesis and underlying mechanisms have not been elucidated. Herein we evaluated the anti-adipogenic effects of GFE and described the underlying mechanisms.

MATERIALS AND METHODS

The effects of ethanol extracts of GFE on adipocyte differentiation were examined in 3T3-L1 cells using biochemical and molecular analyses.

RESULTS

During the differentiation of 3T3-L1 cells, GFE significantly reduced lipid accumulation and downregulated master adipogenic transcription factors, including CCAAT/enhancer-binding protein-α and peroxisome proliferator-activated receptor-γ, at mRNA and protein levels. These changes led to the suppression of several adipogenic-specific genes and proteins, including fatty acid synthase, sterol regulatory element-binding protein 1, stearoyl-CoA desaturase-1, and acetyl CoA carboxylase. However, the inhibitory effects of GFE on lipogenesis were only shown when GFE is treated in the early stage of adipogenesis within the first two days of differentiation. As a potential mechanism, during the early stages of differentiation, GFE inhibited cell proliferation by a decrease in the expression of DNA synthesis-related proteins and increased p27 expression and suppressed signal transducer and activator of transcription 3 (STAT3) activation induced in a differentiation medium.

CONCLUSIONS

GFE inhibits lipogenesis by negative regulation of adipogenic transcription factors, which is associated with GFE-mediated cell cycle arrest and STAT3 inhibition.

Multimeric Amphipathic α-Helical Sequences for Rapid and Efficient Intracellular Protein Transport at Nanomolar Concentrations

An amphipathic leucine (L) and lysine (K)-rich α-helical peptide is multimerized based on helix-loop-helix structures to maximize the penetrating activities. The multimeric LK-based cell penetrating peptides (LK-CPPs) can penetrate cells as protein-fused forms at 100-1000-fold lower concentrations than Tat peptide. The enhanced penetrating activity is increased through multimerization by degrees up to the tetramer level. The multimeric LK-CPPs show rapid cell penetration through macropinocytosis at low nanomolar concentrations, unlike the monomeric LK, which have slower penetrating kinetics at much higher concentrations. The heparan sulfate proteoglycan (HSPG) receptors are highly involved in the rapid internalization of multimeric LK-CPPs. As a proof of concept of biomedical applications, an adipogenic transcription factor, peroxisome proliferator-activated receptor gamma 2 (PPAR-γ 2), is delivered into preadipocytes, and highly enhanced expression of adipogenic genes at nanomolar concentrations is induced. The multimeric CPPs can be a useful platform for the intracellular delivery of bio-macromolecular reagents that have difficulty with penetration in order to control biological reactions in cells at feasible concentrations for biomedical purposes.

Conjugated linoleic acid enriched skim milk prepared with Lactobacillus fermentum DDHI27 endorsed antiobesity in mice

Aim: This study evaluated the antiobesity effect of skim milk prepared with conjugated linoleic acid producing probiotic Lactobacillus fermentum DDHI27 (PCLA). Materials & methods: C57BL/6 J mice were divided into five groups, and different obesity-associated parameters were studied. Results: PCLA supplementation alleviated body weight, epididymal and mesenteric fats and improves lipid profiles. Significant ameliorations in leptin, blood glucose, hepatic steatosis and reduction in adipocytes size were also observed. Additionally, feeding also led to positive alterations in the adipogenesis transcription factors and key lipogenesis genes. Improvement in the gut microbiota dysbiosis was also revealed. Conclusion: Results inferred that PCLA exerted an antiobesity effect in diet-induced obese mice and may be further developed in the functional foods for the management of obesity.

Label-free quantitative chemical imaging and classification analysis of adipogenesis using mouse embryonic stem cells

Stem cells have received much attention recently for their potential utility in regenerative medicine. The identification of their differentiated progeny often requires complex staining procedures, and is challenging for intermediary stages which are a priori unknown. In this work, the ability of label-free quantitative coherent anti-Stokes Raman scattering (CARS) micro-spectroscopy to identify populations of intermediate cell states during the differentiation of murine embryonic stem cells into adipocytes is assessed. Cells were imaged at different days of differentiation by hyperspectral CARS, and images were analysed with an unsupervised factorization algorithm providing Raman-like spectra and spatially resolved maps of chemical components. Chemical decomposition combined with a statistical analysis of their spatial distributions provided a set of parameters that were used for classification analysis. The first 2 principal components of these parameters indicated 3 main groups, attributed to undifferentiated cells, cells differentiated into committed white pre-adipocytes, and differentiating cells exhibiting a distinct protein globular structure with adjacent lipid droplets. An unsupervised classification methodology was developed, separating undifferentiated cell from cells in other stages, using a novel method to estimate the optimal number of clusters. The proposed unsupervised classification pipeline of hyperspectral CARS data offers a promising new tool for automated cell sorting in lineage analysis.

Inhibition of the RhoGTPase Cdc42 by ML141 enhances hepatocyte differentiation from human adipose-derived mesenchymal stem cells via the Wnt5a/PI3K/miR-122 pathway: impact of the age of the donor

Background

Human adipose-derived mesenchymal stem cells (hADSCs) are promising cells that may promote hepatocyte differentiation (Hep-Dif) and improve liver function, but the involvement of Cdc42, a key small RhoGTPase which plays a crucial role in aging, is still not well established. We hypothesized that the inhibition of Cdc42 may rescue the hepatogenic potential of hADSCs derived from aged donors.

Methods

hADSCs isolated from 61 women of different ages were cultured for evaluation of the proliferation of cells, adherence, apoptosis, immunomodulation, immunophenotyping, multipotency, gene expression, and cell function during Hep-Dif. Inhibition of Cdc42 by ML141 was realized during two phases: initiation (days –2 to 14 (D–2/14)) from undifferentiated to hepatoblast-like cells, or maturation (days 14 to 28 (D14/28)) from undifferentiated to hepatocyte-like cells. Mechanistic insights of the Wnt(s)/MAPK/PI3K/miR-122 pathways were studied.

Results

Cdc42 activity in undifferentiated hADSCs showed an age-dependent significant increase in Cdc42-GTP correlated to a decrease in Cdc42GAP; the low potentials of cell proliferation, doubling, adherence, and immunomodulatory ability (proinflammatory over anti-inflammatory) contrary to the apoptotic index of the aged group were significantly reversed by ML141. Aged donor cells showed a decreased potential for Hep-Dif which was rescued by ML141 treatment, giving rise to mature and functional hepatocyte-like cells as assessed by hepatic gene expression, cytochrome activity, urea and albumin production, low-density lipoprotein (LDL) uptake, and glycogen storage. ML141-induced Hep-Dif showed an improvement in mesenchymal-epithelial transition, a switch from Wtn-3a/β-catenin to Wnt5a signaling, involvement of PI3K/PKB but not the MAPK (ERK/JNK/p38) pathway, induction of miR-122 expression, reinforcing the exosomes release and the production of albumin, and epigenetic changes. Inhibition of PI3K and miR-122 abolished completely the effects of ML141 indicating that inhibition of Cdc42 promotes the Hep-Dif through a Wnt5a/PI3K/miR-122/HNF4α/albumin/E-cadherin-positive action. The ML141(D–2/14) protocol had more pronounced effects when compared with ML141(D14/28); inhibition of DNA methylation in combination with ML141(D–2/14) showed more efficacy in rescuing the Hep-Dif of aged hADSCs. In addition to Hep-Dif, the multipotency of aged hADSC-treated ML141 was observed by rescuing the adipocyte and neural differentiation by inducing PPARγ/FABP4 and NeuN/O4 but inhibiting Pref-1 and GFAP, respectively.

Conclusion

ML141 has the potential to reverse the age-related aberrations in aged stem cells and promotes their hepatogenic differentiation. Selective inhibition of Cdc42 could be a potential target of drug therapy for aging and may give new insights on the improvement of Hep-Dif.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-0910-5) contains supplementary material, which is available to authorized users.

A Review on the Weight-Loss Effects of Oxidized Tea Polyphenols

The mechanistic systems in the body through which tea causes weight loss are complex and multi-dimensional. Additionally, the bioactive components in tea such as catechins, caffeine, and products of tea polyphenol oxidation vary greatly from one major tea type to the next. Green tea has been the primary subject of consideration for investigation into the preventative health effects of tea because it contains the highest levels of phenolic compounds and retains the highest antioxidant capabilities of any major tea type. However, recent research suggests decreasing body fat accumulation has little to do with antioxidant activity and more to do with enzyme inhibition, and gut microbiota interactions. This paper reviews several different tea polyphenol-induced weight-loss mechanisms, and purposes a way in which these mechanisms may be interrelated. Our original 'short-chain fatty acid (SCFA) hypothesis' suggests that the weight-loss efficacy of a given tea is determined by a combination of carbohydrate digestive enzyme inhibition and subsequent reactions of undigested carbohydrates with gut microbiota. These reactions among residual carbohydrates, tea polyphenols, and gut microbiota within the colon produce short-chain fatty acids, which enhance lipid metabolism through AMP-activated protein kinase (AMPK) activation. Some evidence suggests the mechanisms involved in SCFA generation may be triggered more strongly by teas that have undergone fermentation (black, oolong, and dark) than by non-fermented (green) teas. We discussed the mechanistic differences among fermented and non-fermented teas in terms of enzyme inhibition, interactions with gut microbiota, SCFA generation, and lipid metabolism. The inconsistent results and possible causes behind them are also discussed.

Specific markers and properties of synovial mesenchymal stem cells in the surface, stromal, and perivascular regions

Background

Synovial mesenchymal stem cells (MSCs) are an attractive cell source for cartilage and meniscus regeneration. Synovial tissue can be histologically classified into three regions; surface, stromal and perivascular region, but the localization of synovial MSCs has not been fully investigated. We identified markers specific for each region, and compared properties of MSCs derived from each region in the synovium.

Methods

The intensity of immunostaining with 19 antibodies was examined for surface, stromal, and perivascular regions of human synovium from six osteoarthritis patients. Specific markers were identified and synovial cells derived from each region were sorted. Proliferation, surface marker expression, chondrogenesis, calcification and adipogenesis potentials were compared in synovial MSCs derived from the three regions.

Results

We selected CD55⁺ CD271⁻ for synovial cells in the surface region, CD55⁻ CD271⁻ in the stromal region, and CD55⁻ CD271⁺ in the perivascular region. The ratio of the sorted cells to non-hematopoietic lineage cells was 5% in the surface region, 70% in the stromal region and 15% in the perivascular region. Synovial cells in the perivascular fraction had the greatest proliferation potential. After expansion, surface marker expression profiles and adipogenesis potentials were similar but chondrogenic and calcification potentials were higher in synovial MSCs derived from the perivascular region than in those derived from the surface and stromal regions.

Conclusions

We identified specific markers to isolate synovial cells from the surface, stromal, and perivascular regions of the synovium. Synovial MSCs in the perivascular region had the highest proliferative and chondrogenic potentials among the three regions.

Lysophosphatidylcholine acyltransferase 3 deficiency impairs 3T3L1 cell adipogenesis through activating Wnt/β-catenin pathway

Levels of polyunsaturated phosphatidylcholine (PC) influence plasma membrane structure and function. Phosphatidylcholine (PC) is synthesized de novo in the Kennedy pathway and then undergoes extensive deacylation/reacylation remodeling via Lands' cycle (non-Kennedy pathway). The reacylation is catalyzed by lysophosphatidylcholine acyltransferase (LPCAT), which adds a polyunsaturated fatty acid at the sn-2 position. Four LPCAT isoforms have been described to date, among which we found LPCAT3 to be the major isoform in adipose tissue, but its exact role in adipogenesis is unclear. In this study, we aimed to investigate whether LPCAT3 activity affects 3T3L1 cell adipogenic differentiation potential and its underline mechanism. Lentivirus-mediated LPCAT3 shRNA expression stably knocked down LPCAT3 in 3T3L1 preadipocytes and LPCAT3 deficiency dramatically reduced the levels of cellular polyunsaturated PCs. Importantly, we found that this deficiency activated the β-catenin dependent Wnt signaling pathway, which suppressed the expression of adipogenesis-related genes, thereby inhibiting 3T3L1 preadipocyte differentiation and lipid accumulation. Moreover, three different Wnt/β-catenin pathway inhibitors reversed the effect of LPCAP3 deficiency, suggesting that Wnt/β-catenin pathway activation is one of the causes for the observed phenotypes. To the best of our knowledge, we show here for the first time that PC remodeling is an important regulator of adipocyte differentiation.

Integration of human adipocyte chromosomal interactions with adipose gene expression prioritizes obesity-related genes from GWAS

Increased adiposity is a hallmark of obesity and overweight, which affect 2.2 billion people world-wide. Understanding the genetic and molecular mechanisms that underlie obesity-related phenotypes can help to improve treatment options and drug development. Here we perform promoter Capture Hi-C in human adipocytes to investigate interactions between gene promoters and distal elements as a transcription-regulating mechanism contributing to these phenotypes. We find that promoter-interacting elements in human adipocytes are enriched for adipose-related transcription factor motifs, such as PPARG and CEBPB, and contribute to heritability of cis-regulated gene expression. We further intersect these data with published genome-wide association studies for BMI and BMI-related metabolic traits to identify the genes that are under genetic cis regulation in human adipocytes via chromosomal interactions. This integrative genomics approach identifies four cis-eQTL-eGene relationships associated with BMI or obesity-related traits, including rs4776984 and MAP2K5, which we further confirm by EMSA, and highlights 38 additional candidate genes.

Plasticizers used in food-contact materials affect adipogenesis in 3T3-L1 cells

Recent studies suggest that exposure to some plasticizers, such as Bisphenol A (BPA), play a role in endocrine/metabolic dispruption and can affect lipid accumulation in adipocytes. Here, we investigated the adipogenic activity and nuclear receptor interactions of four plasticizers approved for the manufacturing of food-contact materials (FCMs) and currently considered safer alternatives. Differentiating 3T3-L1 mouse preadipocytes were exposed to scalar concentrations (0.01-25 μM) of DiNP (Di-iso-nonyl-phthalate), DiDP (Di-iso-decyl-phthalate), DEGDB (Diethylene glycol dibenzoate), or TMCP (Tri-m-cresyl phosphate). Rosiglitazone, a well-known pro-adipogenic peroxisome proliferator activated receptor gamma (PPARγ) agonist, and the plasticizer BPA were included as reference compounds. All concentrations of plasticizers were able to enhance lipid accumulation, with TMCP being the most effective one. Accordingly, when comparing in silico the ligand binding efficiencies to the nuclear receptors PPARγ and retinoid-X-receptor-alpha (RXRα), TMPC displayed the highest affinity to both receptors. Differently from BPA, the four plasticizers were most effective in enhancing lipid accumulation when added in the mid-late phase of differentiation, thus suggesting the involvement of different intracellular signalling pathways. In line with this, TMCP, DiDP, DiNP and DEGDB were able to activate PPARγ in transient transfection assays, while previous studies demonstrated that BPA acts mainly through other nuclear receptors. qRT-PCR studies showed that all plasticizers were able to increase the expression of CCAAT/enhancer binding protein β (Cebpβ) in the early steps of adipogenesis, and the adipogenesis master gene Pparγ2 in the middle phase, with very similar efficacy to that of Rosiglitazone. In addition, TMCP was able to modulate the expression of both Fatty Acid Binding Protein 4/Adipocyte Protein 2 (Fabp4/Ap2) and Lipoprotein Lipase (Lpl) transcripts in the late phase of adipogenesis. DEGDB increased the expression of Lpl only, while the phthalate DiDP did not change the expression of either late-phase marker genes Fabp4 and Lpl. Taken together, our results suggest that exposure to low, environmentally relevant doses of the plasticizers DiNP, DiDP, DEGDB and TMCP increase lipid accumulation in 3T3-L1 adipocytes, an effect likely mediated through activation of PPARγ and interference at different levels with the transcriptional cascade driving adipogenesis.

Strigolactone GR24 and pinosylvin attenuate adipogenesis and inflammation of white adipocytes

Obesity is characterized by excess fat accumulation in white adipose tissue, which triggers chronic low-grade inflammation through secretion of pro-inflammatory factors by the enlarged adipocytes and infiltrated macrophages. This affects glucose and lipid metabolism in adipose tissue, inducing type 2 diabetes. NAD⁺-dependent deacetylase SIRT1 is known to inhibit adipogenesis through the regulation of the key adipogenic transcription factors, PPARγ and C/EBPα. SIRT1 activators such as resveratrol inhibit adipogenesis and exert anti-inflammatory responses in the adipose tissue. We aimed to investigate the role of two SIRT1 activating plant-derived compounds, strigolactone analog GR24 and pinosylvin, in adipogenesis and inflammation of murine adipocytes. 3T3-L1 preadipocytes were differentiated into adipocytes and were treated with GR24 and pinosylvin. Resveratrol was used as a reference treatment. The effects of these compounds on adipogenesis and inflammation were explored by different methods such as cytotoxicity assays, lipid staining, western blotting and ELISA. GR24 upregulated SIRT1 and enhanced the production of NAD⁺, an essential SIRT1 substrate. GR24, pinosylvin and resveratrol attenuated adipogenesis via inhibiting the expression of PPARγ and C/EBPα and protected against inflammation by inhibiting TNF-α-stimulated IL-6 secretion. GR24 also inhibited NF-κB activation. Our results demonstrate for the first time the beneficial effects of strigolactone GR24 and pinosylvin on adipogenesis and inflammation in adipocytes.

Euglena extract suppresses adipocyte-differentiation in human adipose-derived stem cells

Euglena gracilis Z (Euglena) is a unicellular, photosynthesizing, microscopic green alga. It contains several nutrients such as vitamins, minerals, and unsaturated fatty acids. In this study, to verify the potential role of Euglena consumption on human health and obesity, we evaluated the effect of Euglena on human adipose-derived stem cells. We prepared a Euglena extract and evaluated its effect on cell growth and lipid accumulation, and found that cell growth was promoted by the addition of the Euglena extract. Interestingly, intracellular lipid accumulation was inhibited in a concentration-dependent manner. Quantitative real-time PCR analysis and western blotting analysis indicated that the Euglena extract suppressed adipocyte differentiation by inhibiting the gene expression of the master regulators peroxisome proliferator-activated receptor-γ (PPARγ) and one of three CCAAT-enhancer-binding proteins (C/EBPα). Further Oil Red O staining experiments indicated that the Euglena extract inhibited the early stage of adipocyte-differentiation. Consistent with these results, we observed that down-regulation of gene expression was involved in the early stage of adipogenesis represented by the sterol regulatory element binding protein 1 c (SREBP1c), two of three CCAAT-enhancer-binding proteins (C/EBPβ, C/EBPδ), and the cAMP regulatory element-binding protein (CREB). Taken together, these data suggest that Euglena extract is a promising candidate for the development of a new therapeutic treatment for obesity.

Adipose depot-specific effects of ileal interposition surgery in UCD-T2D rats: unexpected implications for obesity and diabetes

Ileal interposition (IT) surgery delays the onset of diabetes in a rat model of type-2 diabetes (UCD-T2DM). Here, to gain a deeper understanding of the molecular events underlying the effects of IT surgery, we examined the changes in the proteome of four white adipose depots (retroperitoneal, mesenteric, inguinal, and epididymal) and plasma-free fatty acid profile in pre-diabetic rats 1.5 months following IT or sham surgery. The IT-mediated changes were exerted mainly in mesenteric fat and spanned from delayed adipocyte maturation to a neuroendocrine remodeling. Conversely, inguinal, retroperitoneal, and epididymal depots showed opposite trends consistent with increased adipocyte maturation and adipogenesis development prior to overt signs of diabetes, probably orchestrated by peroxisome proliferator-activated receptor gamma signaling and higher plasma n-6/n-3 free fatty acid ratios. The resulting scenario suggests a targeted use of surgical strategies that seek to delay or improve diabetes in order to manipulate adipose depot-specific responses to maximize the duration and beneficial effects of the surgery.

Progress in the use of dental pulp stem cells in regenerative medicine

The field of tissue engineering is emerging as a multidisciplinary area with promising potential for regenerating new tissues and organs. This approach requires the involvement of three essential components: stem cells, scaffolds and growth factors. To date, dental pulp stem cells have received special attention because they represent a readily accessible source of stem cells. Their high plasticity and multipotential capacity to differentiate into a large array of tissues can be explained by its neural crest origin, which supports applications beyond the scope of oral tissues. Many isolation, culture and cryopreservation protocols have been proposed that are known to affect cell phenotype, proliferation rate and differentiation capacity. The clinical applications of therapies based on dental pulp stem cells demand the development of new biomaterials suitable for regenerative purposes that can act as scaffolds to handle, carry and implant stem cells into patients. Currently, the development of xeno-free culture media is emerging as a means of standardization to improve safe and reproducibility. The present review aims to describe the current knowledge of dental pulp stem cells, considering in depth the key aspects related to the characterization, establishment, maintenance and cryopreservation of primary cultures and their involvement in the multilineage differentiation potential. The main clinical applications for these stem cells and their combination with several biomaterials is also covered.

Modulation of Adipocyte Differentiation and Proadipogenic Gene Expression by Sulforaphane, Genistein, and Docosahexaenoic Acid as a First Step to Counteract Obesity

Obesity is characterized by excess body fat accumulation due to an increase in the size and number of differentiated mature adipocytes. Adipocyte differentiation is regulated by genetic and environmental factors, and its inhibition could represent a strategy for obesity prevention and treatment. The current study was designed with two aims: (i) to evaluate the changes in the expression of adipogenic markers (C/EBPα, PPARγ variant 1 and variant 2, and GLUT4) in 3T3-L1 murine preadipocytes at four stages of the differentiation process and (ii) to compare the effectiveness of sulforaphane, genistein, and docosahexaenoic acid in reducing lipid accumulation and modulating C/EBPα, PPARγ1, PPARγ2, and GLUT4 mRNA expression in mature adipocytes. All bioactive compounds were shown to suppress adipocyte differentiation, although with different effectiveness. These results set the stage for further studies considering natural food constituents as important agents in preventing or treating obesity.

Resveratrol Intake During Pregnancy and Lactation Modulates the Early Metabolic Effects of Maternal Nutrition Differently in Male and Female Offspring

Poor maternal nutrition can have detrimental long-term consequences on energy homeostasis in the offspring. Resveratrol exerts antioxidant and antiobesity actions, but its impact during development remains largely unknown. We hypothesized that resveratrol intake during pregnancy and lactation could improve the effects of poor maternal nutrition on offspring metabolism. Wistar rats received a low-fat diet (LFD; 10.2% kcal from fat) or high-fat diet (HFD; 61.6% kcal from fat), with half of each group receiving resveratrol in their drinking water (50 mg/L) during pregnancy and lactation. Body weight (BW) of dams was measured at treatment onset and weaning [postnatal day (PND) 21] and of pups at birth and PND21, at which time dams and pups were euthanized. Although HFD dams consumed more energy, their BW at the end of lactation was unaffected. Mean litter size was not modified by maternal diet or resveratrol. At birth, male offspring from HFD and resveratrol (HFD + R) dams weighed less than those from LFD and resveratrol (LFD + R) dams. On PND21, pups of both sexes from HFD dams weighed more, had more visceral adipose tissue (VAT) and subcutaneous adipose tissue (SCAT), and had higher serum leptin levels than those from LFD dams. Resveratrol reduced BW, leptin, VAT, and SCAT, with females being more affected, but increased glycemia. Neuropeptide levels were unaffected by resveratrol. In conclusion, resveratrol intake during pregnancy and lactation decreased BW and adipose tissue content in offspring of dams on an HFD but did not affect offspring from LFD-fed dams, suggesting that the potential protective effects of resveratrol during gestation/lactation are diet dependent.

The clinical potential of adipogenesis and obesity-related microRNAs

Obesity is a growing health problem commonly associated with numerous metabolic disorders including type 2 diabetes, hypertension, cardiovascular disease, and some forms of cancer. The burden of obesity and associated cardiometabolic diseases are believed to arise through complex interplay between genetics and epigenetics predisposition, nutrition, environment, and lifestyle. However, the molecular basis and the repertoire of obesity-affecting factors are still unknown. Emerging evidence is connecting microRNAs (miRNAs) dysregulation with adipogenesis and obesity. Alteration in miRNAs expression could result in changes in the pattern of genes controlling a range of biological processes including inflammation, lipid metabolism, insulin resistance and adipogenesis. Hence, understanding exact roles of miRNAs as well as the degree of their contribution to the regulation of adipogenesis and fat cell development in obesity would provide new therapeutic targets for the development of novel and effective anti-obesity drugs. The objective of the current review is to: (i) discuss some of the latest development on relevant miRNAs dysregulation mainly in human adipogenesis and obesity, (ii) emphasize the role of circulating miRNAs as new promising therapeutics and attractive potential biomarkers for treating obesity and associated risk factor diseases, (iii) describe how dietary factors may influence obesity through modulation of miRNAs expression, (iv) highlight some of the actual limitations to the promise of miRNAs as novel therapeutics as well as to their translation for the benefit of patients, and finally (v) provide recommendations for future research on miRNA-based therapeutics that could lead to a breakthrough in the treatment of obesity and its associated pathologies.

The Effects of Hyperacute Serum on Adipogenesis and Cell Proliferation of Mesenchymal Stromal Cells

Fat tissue, due to its high concentration of stem cells, has a role in aesthetic medicine and reconstructive surgery. However, poor survival of the transplanted cells still limits the usefulness of this material in regenerative medicine. Several studies indicated that platelet-rich plasma (PRP) may improve adipose tissue viability due to its growth factor content. This study aimed at investigating the effects of PRP and hyperacute serum (HAS) on the adipogenic lineage in vitro. PRP was prepared by using two centrifugation steps in the presence of anticoagulants, and HAS was isolated from activated platelet-rich fibrin within 10 min of blood drawing to prevent the propagation of inflammatory cascades. Metabolic activity and proliferation rate of human bone marrow-derived mesenchymal stem cells (hMSCs) cultivated in media supplemented with three types of serum additives (fetal calf serum [FCS], human PRP, or HAS) was determined by using a tetrazolium assay. Adipogenesis was evaluated in standard and pro-adipogenic media and tested by oil red staining, triglyceride content, and expression of specific genes. Adipogenic regulators in the sera were measured by multiplex ELISA assays. We observed that proliferation of hMSCs was supported by both FCS and HAS in a time-dependent manner, but surprisingly, PRP had a much weaker effect (change in proliferation rate after 5 days relative to metabolic activity on day 0-FCS: 5.4-fold change, HAS: 5.8-fold change, serum free 1.9-fold change, PRP: 3.0-fold change, p < 0.05). Lipogenesis was only observed in groups with adipogenic differentiation medium, with HAS showing a significantly stronger effect than PRP. This was confirmed by intensive accumulation of lysochrome dye in lipid droplets, higher triglyceride concentration, and elevated expression of specific adipogenic genes. Measurement of lipogenic proteins in the sera revealed that both PRP and HAS are abundant in them; however, PRP also contains anti-adipogenic factors, which explains its weaker and less reliable effect. The results of this study suggest that HAS provides more robust support than PRP in hMSCs proliferation as well as lipogenic differentiation, indicating that it may be a better adjuvant in fat grafting procedures.

Cysteine-rich protein 61 regulates adipocyte differentiation from mesenchymal stem cells through mammalian target of rapamycin complex 1 and canonical Wnt signaling

Emerging evidence suggests that cysteine-rich protein 61 (CYR61) plays a role in the differentiation and development of chondrocytes, osteoblasts, and osteoclasts; however, little is known about its role in adipogenesis. The current study indicates that the expression level of Cyr61 was altered in primary cultured marrow stromal cells and the established mesenchymal cell line, C3H10T1/2, after adipogenic treatment. Overexpressing Cyr61 repressed C3H10T1/2 and primary marrow stromal cells to differentiate into mature adipocytes. Conversely, inhibition of endogenous Cyr61 induced C3H10T1/2 and primary marrow stromal cells to fully differentiate. Mechanism investigations reveal that knockdown of Cyr61 inhibited the nuclear translocation of β-catenin and decreased nuclear protein levels of β-catenin and transcription factor 7-like 2. Moreover, the silencing of Cyr61 increased protein levels of phosphorylated ribosomal protein S6 kinase B1, mammalian target of rapamycin, eukaryotic translation initiation factor 4E-binding protein 1, and ribosomal protein S6-the major components of mammalian target of rapamycin complex 1 (mTORC1) signaling-in C3H10T1/2 cells. Additional investigations demonstrated that treatment with rapamycin significantly attenuated adipocyte formation that was induced by Cyr61 small interfering RNA (siRNA) transfection. Moreover, Cyr61 siRNA also lost its ability to stimulate adipocyte formation under the background of β-catenin overexpression. Taken together, our study provides evidence that CYR61 regulates adipocyte differentiation via multiple signaling pathways that involve at least the inactivation of mTORC1 signaling and the activation of canonical Wnt signaling.-Yang, Y., Qi, Q., Wang, Y., Shi, Y., Yang, W., Cen, Y., Zhu, E., Li, X., Chen, D., Wang, B. Cysteine-rich protein 61 regulates adipocyte differentiation from mesenchymal stem cells through mammalian target of rapamycin complex 1 and canonical Wnt signaling.

Isolation and Characterization of Bone Marrow Mesenchymal Stromal Cell Subsets in Culture Based on Aldehyde Dehydrogenase Activity

Mesenchymal stromal cells (MSCs) have particular properties that allow their use as therapeutic strategies for several cell-based applications. Historically, bone marrow (BM)-MSCs are isolated by culture adherence since specific cell surface markers are yet to be developed. This original work aimed to identify and characterize isolating expanded BM-MSCs based on their aldehyde dehydrogenase (ALDH) activity known to be a hallmark of stem cells and relevant for their isolation. We thus isolated by fluorescence-activated cell sorting technology two functionally different populations of BM-MSCs depending on their ALDH activity (ALDH⁺ and ALDH^-). Transcriptome analysis and profiling clearly demonstrated that both populations of BM-MSCs present distinct pattern of genes related to the main properties of MSCs (proliferation, response to hypoxia, angiogenesis, phenotype, stemness, multilineage, hematopoiesis, immunomodulation) in an ALDH activity dependent manner. Both BM-MSC populations look to significantly differ in terms of biological responses and functionalities. More functional analyses are needed to understand and characterize the properties of these ALDH populations. Collectively, our results highlight ALDH activity as a potential feature for isolating and segregating functional and/or competent subset of BM-MSC populations, which may account for better and more efficient therapeutic issue.

The Impact of Lipid Types and Liposomal Formulations on Osteoblast Adiposity and Mineralization

Recent studies have demonstrated that fat accumulation in bone cells is detrimental to bone mass. Both adipocytes and osteoblasts are derived from common multipotent mesenchymal stem cells (MSCs) and hence the presence of fat may increase adipocyte proliferation, differentiation and fat accumulation while inhibiting osteoblast differentiation and bone formation. Lipids are common constituents in supramolecular vesicles (e.g., micelles or liposomes) that serve as drug delivery systems. Liposomal formulations such as Meriva^® were proven to decrease joint pain and improve joint function in osteoarthritis (OA) patients. In this study, we evaluated how lipid types and liposomal formulations affect osteoblast behavior including cell viability, differentiation, mineralization and inflammation. Various liposomal formulations were prepared using different types of lipids, including phosphatidylcholine (PC), 1,2-dioleoyl-sn-glycero-3-phospho-ethanolamine (DOPE), cholesterol (Chol), 3β-[N-(N′,N′-dimethylaminoethane)-carbamoyl] cholesterol hydrochloride (DC-cholesterol HCl), and 1,2-dioleoyl-3-trimethylammonium-propane chloride salt (DOTAP) to investigate the impact on osteoblast differentiation and inflammation. The results indicated that cationic lipids, DC-cholesterol and DOTAP, presented higher dose-dependent cytotoxicity and caused high level of inflammatory responses. Due to the natural properties of lipids, all the lipids can induce lipid droplet formation in osteoblasts but the level of lipid droplet accumulation was different. In comparison with cationic lipids, neutral lipids induced less adiposity, and maintained high osteoblast mineralization. Similar to previous researches, we also confirmed an inverse relationship between lipid droplet formation and osteoblast mineralization in 7F2 mouse osteoblasts. Importantly, PC containing liposomes (PC only and PC/DOTAP) suppressed IL-1β-induced gene expression of COX-2 and MMP-3 but not Chol/DOTAP liposomes or DC-Chol/DOPE liposomes. Taken together, we suggested that PC contained liposomes could provide the best liposomal formulation for the treatment of bone diseases.