A Citrus bergamia Extract Decreases Adipogenesis and Increases Lipolysis by Modulating PPAR Levels in Mesenchymal Stem Cells from Human Adipose Tissue. PPAR Res. 2016;2016:4563815. [PMID: 27403151 PMCID: PMC4926019 DOI: 10.1155/2016/4563815]

In vitro effects of phytochemicals on adipogenesis with a focus on molecular mechanisms: A systematic review

Adipogenesis, the process of proliferation of adipocyte progenitor cells and their differentiation into mature adipocytes, plays a critical role in the development of obesity. In this context, exploring the effects of phytochemicals on adipogenesis is very promising, as nowadays, they are widely used as food, drink, or supplement and can significantly impact general health and obesity control. This systematic review attempts to evaluate new findings regarding the molecular mechanisms of different phytochemicals on adipogenesis in in vitro models. Between 2010 and July 2023, a comprehensive systematic search of PubMed and Scopus databases was conducted. The following keywords were used: ("adipogenic") AND ("inhibit" OR "suppress" OR "reduce" OR "anti" OR "decrease") AND ("cell" OR "cell line" OR "adipocyte") AND ("phytochemical" OR "plant" OR "herb"). In this review, 109 studies were comprehensively analyzed, which provided important insights into the process of adipogenesis. Among the numerous transcription factors studied, PPARγ, C/EBPα, and SREBP1c were found to be the most important regulators actively involved in adipocyte differentiation. These results highlight the critical role of these factors in the control of adipogenesis and suggest that they represent promising targets for therapeutic interventions aimed at reducing the excessive lipid accumulation associated with obesity. This study provides a compelling rationale for further exploring phytochemicals as potential therapeutics for treating obesity. The potential benefits of using natural products to influence adipogenesis are evident, and future studies should focus on translating these findings into clinical applications.

Biological activities, Molecular mechanisms, and Clinical application of Naringin in Metabolic syndrome

Metabolic syndrome has become major health problems in recent decades, and natural compounds receive considerable attention in the management of metabolic syndrome. Among them, naringin is abundant in citrus fruits and tomatoes. Many studies have investigated the therapeutic effects of naringin in metabolic syndrome. This review discusses in vitro and in vivo studies on naringin and implications for clinical trials on metabolic syndrome such as diabetes mellitus, obesity, nonalcoholic fatty liver disease, dyslipidemia, and hypertension over the past decades, overviews the molecular mechanisms by which naringin targets metabolic syndrome, and analyzes possible correlations between the different mechanisms. This review provides a theoretical basis for the further application of naringin in the treatment of metabolic syndrome.

Effects of Citrus depressa Hayata juice on high-fat diet-induced obesity in HBV transgenic mice

The present study investigated the potential anti-obesity properties of Citrus depressa Hayata (CDH) juice in HBV transgenic mice, as well as the impact of fermentation on the effectiveness of the juice. The results revealed that fermentation increased the levels of polyphenols and hesperidin in CDH juice. The animal study demonstrated that both juices were effective in mitigating the weight gain induced by a high-fat diet by correcting metabolic parameter imbalances, reducing hepatic lipid accumulation, and reversing hepatic immune suppression. Furthermore, fermented juice exhibited superior efficacy in managing body weight and inhibiting the expansion of white adipose tissue (WAT). Fermented juice significantly enhanced adiponectin production and PPARγ expression in WAT, while also reducing hypertrophy. This study offers valuable insights into the potential role of CDH juices in combating obesity associated with high fat consumption and underscores the promise of CDH juice as a functional beverage.

Naringin reduces fat deposition by promoting the expression of lipolysis and β-oxidation related genes

AIMS

Naringin, a flavonoid present in citrus fruits, has been known for the capacity to reduce lipid synthesis and anti-inflammatory. In this study, we investigated whether naringin increases lipolysis and fatty acid β-oxidation to change fat deposition.

METHODS

In in vivo experiment, obese adult mice (20-weeks-old, n = 18) were divided into control group fed with normal diet and naringin-treated group fed with naringin-supplemented diet (5 g/kg) for 60 days, respectively. In in vitro experiment, differentiated 3T3-L1 adipocytes were treated for four days with or without naringin (100 µg/mL).

RESULTS

Supplementing naringin significantly reduced the body weight, abdominal fat weight, blood total cholesterol content of mice, but did not affect food intake. In addition, naringin decreased levels of pro-inflammatory factors in adipose tissue including interleukin-1β (IL-1β), interleukin-6 (IL-6), and monocyte chemotactic protein 1 (MCP-1). Naringin increased the expression of AMP-activated protein kinase (AMPK), a key factor in cellular energy metabolism, and raised the ratio of p-AMPK/AMPK in mouse liver tissue. The protein expression of hormone-sensitive lipase (HSL), phospho-HSL563 (p-HSL563), p-HSL563/HSL, and adipocyte triglyceride lipase (ATGL) was significantly increased in the adipose tissue of naringin-treated mice. Furthermore, naringin enhanced the expression of fatty acid β-oxidation genes, including carnitine palmitoyl transferase 1 (CPT1), uncoupling protein 2 (UCP2), and acyl-coenzyme A oxidase 1 (AOX1) in mouse adipose tissue. In in vitro experiment, similar findings were observed in differentiated 3T3-L1 adipocytes with naringin treatment. The treatment remarkably reduced intracellular lipid content, increased the number of mitochondria and promoted the gene expression of HSL, ATGL, CPT1, AOX1, and UCP2 and the phosphorylation of HSL protein.

CONCLUSION

Naringin reduced body fat in obese mice and lipid content in differentiated 3T3-L1 adipocytes, which was associated with enhanced AMPK activation and upregulation of the expression of the lipolytic genes HSL, ATGL, and β-oxidation genes CPT1, AOX1, and UCP2.

Effectiveness of "Moro" Blood Orange Citrus sinensis Osbeck (Rutaceae) Standardized Extract on Weight Loss in Overweight but Otherwise Healthy Men and Women-A Randomized Double-Blind Placebo-Controlled Study

This study aimed to assess the efficacy of a blood orange Citrus sinensis standardized extract from “Moro” cultivar, on weight loss in overweight but otherwise healthy individuals. Anthocyanins and particularly cyanidin 3-glucoside, found in a large variety of fruits including Sicilian blood oranges, can help to counteract weight gain and to reduce body fat accumulation through the modulation of antioxidant, anti-inflammatory and metabolic pathways. In this randomized, double blind, placebo-controlled study, all participants (overweight adults aged 20−65 years old) were randomized to receive either Moro blood orange standardized extract or a placebo daily for 6-months. The primary outcome measure was change in body mass and body composition at the end of the study. After 6-months, body mass (4.2% vs. 2.2%, p = 0.015), body mass index (p = 0.019), hip (3.4 cm vs. 2.0 cm, p = 0.049) and waist (3.9 cm vs. 1.7 cm, p = 0.017) circumferences, fat mass (p = 0.012) and fat distribution (visceral and subcutaneous fat p = 0.018 and 0.006, respectively) were all significantly better in the extract supplemented group compared to the placebo (p < 0.05). In addition, all safety markers of liver toxicity were within the normal range throughout the study for both analyzed groups. Concluding, the present study demonstrates that Moro blood orange standardized extract may be a safe and effective option for helping with weight loss when used in conjunction with diet and exercise.

ARPE-19 conditioned medium promotes neural differentiation of adipose-derived mesenchymal stem cells

BACKGROUND

Adipose-derived stem cells (ASCs) have been increasingly explored for cell-based medicine because of their numerous advantages in terms of easy availability, high proliferation rate, multipotent differentiation ability and low immunogenicity. In this respect, they have been widely investigated in the last two decades to develop therapeutic strategies for a variety of human pathologies including eye disease. In ocular diseases involving the retina, various cell types may be affected, such as Müller cells, astrocytes, photoreceptors and retinal pigment epithelium (RPE), which plays a fundamental role in the homeostasis of retinal tissue, by secreting a variety of growth factors that support retinal cells.

AIM

To test ASC neural differentiation using conditioned medium (CM) from an RPE cell line (ARPE-19).

METHODS

ASCs were isolated from adipose tissue, harvested from the subcutaneous region of healthy donors undergoing liposuction procedures. Four ASC culture conditions were investigated: ASCs cultured in basal Dulbecco's Modified Eagle Medium (DMEM); ASCs cultured in serum-free DMEM; ASCs cultured in serum-free DMEM/F12; and ASCs cultured in a CM from ARPE-19, a spontaneously arising cell line with a normal karyotype derived from a human RPE. Cell proliferation rate and viability were assessed by crystal violet and MTT assays at 1, 4 and 8 d of culture. At the same time points, ASC neural differentiation was evaluated by immunocytochemistry and western blot analysis for typical neuronal and glial markers: Nestin, neuronal specific enolase (NSE), protein gene product (PGP) 9.5, and glial fibrillary acidic protein (GFAP).

RESULTS

Depending on the culture medium, ASC proliferation rate and viability showed some significant differences. Overall, less dense populations were observed in serum-free cultures, except for ASCs cultured in ARPE-19 serum-free CM. Moreover, a different cell morphology was seen in these cultures after 8 d of treatment, with more elongated cells, often showing cytoplasmic ramifications. Immunofluorescence results and western blot analysis were indicative of ASC neural differentiation. In fact, basal levels of neural markers detected under control conditions significantly increased when cells were cultured in ARPE-19 CM. Specifically, neural marker overexpression was more marked at 8 d. The most evident increase was observed for NSE and GFAP, a modest increase was observed for nestin, and less relevant changes were observed for PGP9.5.

CONCLUSION

The presence of growth factors produced by ARPE-19 cells in tissue culture induces ASCs to express neural differentiation markers typical of the neuronal and glial cells of the retina.

An exploratory double-blind, randomized, placebo-controlled study to assess the efficacy of CitruSlim on body composition and lipid parameters in obese individuals

The prevalence of obesity in developing and developed countries has been well recognized, and the worldwide obesity rates have nearly tripled since 1975, according to the World Health Organization. CitruSlim, a standardized product containing a blend of Citrus bergamia and Eurycoma longifolia, can reduce cortisol, cholesterol, triglycerides, and hyperglycemia. These properties can contribute to reduction in body weight or body mass index (BMI) in obese patients. A randomized, double-blind, placebo-controlled clinical study was designed to evaluate the efficacy and tolerability of CitruSlim in body weight management in obese individuals, and the results were compared with that of placebo. A total of 97 participants were allocated, randomized, and treated with CitruSlim high-dose (HD, 400 mg), CitruSlim low-dose (LD, 200 mg), and placebo for 112 days. At the end of the study, CitruSlim HD and CitruSlim LD significantly reduced BMI compared to the placebo group and were well tolerated; however, it did not improve parameters associated with dyslipidemia and metabolic disturbances. The study findings suggested that CitruSlim was effective in reducing body weight in obese patients.

Defining the Cholesterol Lowering Mechanism of Bergamot (Citrus bergamia) Extract in HepG2 and Caco-2 Cells

Bergamot, a Mediterranean citrus fruit native to southern Italy, has been reported to have cholesterol-lowering properties; however, the mechanism of action is not well understood. Due to structural similarities with 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) inhibitors, it has been proposed that the phenolic compounds in bergamot may also inhibit HMGCR. Statins are widely used for their cholesterol-lowering properties; however, they are not universally well tolerated, suggesting there is a need to identify novel cholesterol-lowering strategies. In the present study, we investigated bergamot fruit extract (BFE) and its principal components (neoeriocitrin, naringin, neohesperidin, melitidin, and brutieridin) for their ability to regulate cholesterol levels in HepG2 and Caco-2 cells. BFE at increasing concentrations decreased the levels of total and free cholesterol in HepG2 cells. BFE and its constituents did not directly inhibit HMGCR activity. However, BFE and neohesperidin decreased HMGCR levels in HepG2 cells, suggesting that neohesperidin and BFE may downregulate HMGCR expression. An increase in AMP-kinase phosphorylation was observed in BFE and neohesperidin-treated cells. In Caco-2 cells, brutieridin exhibited a significant reduction in cholesterol uptake and decreased the level of Niemann-Pick C1 Like 1, an important cholesterol transporter. Taken together, our data suggest that the cholesterol-lowering activity of bergamot is distinct from statins. We hypothesize that BFE and its principal constituents lower cholesterol by inhibiting cholesterol synthesis and absorption.

Effect of Resistance Exercise on the Lipolysis Pathway in Obese Pre- and Postmenopausal Women

Physical exercise may stimulate lipolytic activity within adipose tissue. Furthermore, resistance exercise may contribute to the more efficient reduction in adipose tissue mass and prevent the accumulation thereof in obese women. The purpose of this study was to examine the effects of regular resistance exercise for 12 weeks on the lipolysis pathway in women with obesity. Twenty-three pre- and postmenopausal women with body fat percentages of 30% or more were divided into the premenopausal group (n = 9) and the postmenopausal group (n = 14). All subjects participated in resistance exercise training for 12 weeks. Anthropometric and physical fitness tests were performed on all participants. Protein analyses were performed on extracted subcutaneous fatty tissue, and changes in the relevant protein levels in the samples were analyzed by Western blotting. All serum samples were submitted for enzyme-linked immunosorbent assay measurements of adipocyte factors. After 12 weeks, the adipose triglyceride lipase, monoacylglycerol lipase, and perilipin1 protein levels were significantly lower in the postmenopausal group than in the premenopausal group. The hormone-sensitive lipase protein levels were significantly higher in the postmenopausal group than in the premenopausal group. In addition, leptin concentrations were significantly decreased after resistance exercise in the postmenopausal group. Adiponectin concentrations were significantly increased after resistance exercise in both groups. These findings indicate that regular resistance exercise is effective in reducing the weight and body fat of obese premenopausal women, and in the secretion of adiponectin. On the other hand, postmenopausal women were found to have redeced weight and body fat, and were found to be positive for the secretion of adipokine factors. In addition, positive changes in lipolysis pathway factors in adipose tissue promote lipid degradation and reduce fat mass. Thus, regular resistance exercise shows positive changes in the lipolysis pathway more effectively in weight and body fat reduction in postmenopausal women than in premenopausal women.

Potential therapeutic applications of mesenchymal stem cells for the treatment of eye diseases

Stem cell-based treatments have been extensively explored in the last few decades to develop therapeutic strategies aimed at providing effective alternatives for those human pathologies in which surgical or pharmacological therapies produce limited effects. Among stem cells of different sources, mesenchymal stem cells (MSCs) offer several advantages, such as the absence of ethical concerns, easy harvesting, low immunogenicity and reduced tumorigenesis risks. Other than a multipotent differentiation ability, MSCs can release extracellular vesicles conveying proteins, mRNA and microRNA. Thanks to these properties, new therapeutic approaches have been designed for the treatment of various pathologies, including ocular diseases. In this review, the use of different MSCs and different administration strategies are described for the treatment of diabetic retinopathy, glaucoma, and retinitis pigmentosa. In a large number of investigations, positive results have been obtained by in vitro experiments and by MSC administration in animal models. Most authors agree that beneficial effects are likely related to MSC paracrine activity. Based on these considerations, many clinical trials have already been carried out. Overall, although some adverse effects have been described, promising outcomes are reported. It can be assumed that in the near future, safer and more effective protocols will be developed for more numerous clinical applications to improve the quality of life of patients affected by eye diseases.

Effects of High Glucose Concentration on Pericyte-Like Differentiated Human Adipose-Derived Mesenchymal Stem Cells

A pericyte-like differentiation of human adipose-derived mesenchymal stem cells (ASCs) was tested in in vitro experiments for possible therapeutic applications in cases of diabetic retinopathy (DR) to replace irreversibly lost pericytes. For this purpose, pericyte-like ASCs were obtained after their growth in a specific pericyte medium. They were then cultured in high glucose conditions to mimic the altered microenvironment of a diabetic eye. Several parameters were monitored, especially those particularly affected by disease progression: cell proliferation, viability and migration ability; reactive oxygen species (ROS) production; inflammation-related cytokines and angiogenic factors. Overall, encouraging results were obtained. In fact, even after glucose addition, ASCs pre-cultured in the pericyte medium (pmASCs) showed high proliferation rate, viability and migration ability. A considerable increase in mRNA expression levels of the anti-inflammatory cytokines transforming growth factor-β1 (TGF-β1) and interleukin-10 (IL-10) was observed, associated with reduction in ROS production, and mRNA expression of pro-inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), and angiogenic factors. Finally, a pmASC-induced better organization of tube-like formation by retinal endothelial cells was observed in three-dimensional co-culture. The pericyte-like ASCs obtained in these experiments represent a valuable tool for the treatment of retinal damages occurring in diabetic patients.

Biological effects of melatonin on human adipose‑derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are capable of differentiating into other cell types and exhibit immunomodulatory effects. MSCs are affected by several intrinsic and extrinsic signaling modulators, including growth factors, cytokines, extracellular matrix and hormones. Melatonin, produced by the pineal gland, is a hormone that regulates sleep cycles. Recent studies have shown that melatonin improves the therapeutic effects of stem cells. The present study aimed to investigate whether melatonin enhances the biological activities of human adipose-derived MSCs. The results demonstrated that treatment with melatonin promoted cell proliferation by inducing SRY-box transcription factor 2 gene expression and preventing replicative senescence. In addition, melatonin exerted anti-adipogenic effects on MSCs. PCR analysis revealed that the expression of the CCAAT enhancer binding protein a gene, a key transcription factor in adipogenesis, was decreased following melatonin treatment, resulting in reduced adipogenic differentiation in an in vitro assay. The present study also examined the effect of melatonin on the immunomodulatory response using a co-culture system of human peripheral blood mononuclear cells and MSCs. Activated T cells were strongly inhibited following melatonin exposure compared with those in the control group. Finally, the favorable effects of melatonin on MSCs were confirmed using luzindole, a selective melatonin receptor antagonist. The proliferation-promoting, anti-inflammatory effects of melatonin suggested that melatonin-treated MSCs may be used for effective cell therapy.

Dietary Intake of Immature Citrus tumida Hort. ex Tanaka Peels Suppressed Body Weight Gain and Fat Accumulation in a Mouse Model of Acute Obesity

Citrus fruits have several potential benefits for maintaining our health. In this study, we investigated the anti-obesity effects of immature Citrus tumida hort. ex Tanaka (C. tumida) peels using an acute obesity mice model. C57BL/6J male mice were divided into 2 groups; HFD-LL subjected to a high fat diet (HFD) and constant light exposure (LL), and HFDC-LL subjected to a HFD containing immature peel powder of C. tumida (5% w/w) and LL. Dietary ingestion of immature C. tumida peels significantly suppressed body weight gain following decreased epidydimal, perirenal, and subcutaneous fat weights. Blood levels of triglyceride and total cholesterol in the HFDC-LL were significantly lower than those in the HFD-LL group; however, there was no significant difference in food or calorie intake between the 2 groups. These results suggested that immature C. tumida peels have a beneficial effect on the prevention of obesity and metabolic syndrome via its biochemical activities of lipid metabolism.

Novel Neohesperidin Dihydrochalcone Analogue Inhibits Adipogenic Differentiation of Human Adipose-Derived Stem Cells through the Nrf2 Pathway

Obesity, characterized by excess lipid accumulation, has emerged as a leading public health problem. Excessive, adipocyte-induced lipid accumulation raises the risk of metabolic disorders. Adipose-derived stem cells (ASCs) are mesenchymal stem cells (MSCs) that can be obtained from abundant adipose tissue. High fat mass could be caused by an increase in the size (hypertrophy) and number (hyperplasia) of adipocytes. Reactive oxygen species (ROS) are involved in the adipogenic differentiation of human adipose-derived stem cells (hASCs). Lowering the level of ROS is important to blocking or retarding the adipogenic differentiation of hASCs. Nuclear factor erythroid 2-related factor-2 (Nrf2) is a transcription factor that mediates various antioxidant enzymes and regulates cellular ROS levels. Neohesperidin dihydrochalcone (NHDC), widely used as artificial sweetener, has been shown to have significant free radical scavenging activity. In the present study, (E)-3-(4-chlorophenyl)-1-(2,4,6-trimethoxyphenyl)prop-2-en-1-one (CTP), a novel NHDC analogue, was synthesized and examined to determine whether it could inhibit adipogenic differentiation. The inhibition of adipogenic differentiation in hASCs was tested using NHDC and CTP. In the CTP group, reduced Oil Red O staining was observed compared with the differentiation group. CTP treatment also downregulated the expression of PPAR-γ and C/EBP-α, adipogenic differentiation markers in hASCs, compared to the adipogenic differentiation group. The expression of FAS and SREBP-1 decreased in the CTP group, along with the fluorescent intensity (amount) of ROS. Expression of the Nrf2 protein was slightly decreased in the differentiation group. Meanwhile, in both the NHDC and CTP groups, Nrf2 expression was restored to the level of the control group. Moreover, the expression of HO-1 and NQO-1 increased significantly in the CTP group. Taken together, these results suggest that CTP treatment suppresses the adipogenic differentiation of hASCs by decreasing intracellular ROS, possibly through activation of the Nrf2 cytoprotective pathway. Thus, the use of bioactive substances such as CTP, which activates Nrf2 to reduce the cellular level of ROS and inhibit the adipogenic differentiation of hASCs, could be a new strategy for overcoming obesity.

Neural differentiation of human adipose-derived mesenchymal stem cells induced by glial cell conditioned media

Adipose-derived mesenchymal stem cells (ASCs) may transdifferentiate into cells belonging to mesodermal, endodermal, and ectodermal lineages. The aim of this study was to verify whether a neural differentiation of ASCs could be induced by a conditioned medium (CM) obtained from cultures of olfactory ensheathing cells (OECs) or Schwann cells (SCs). ASCs were isolated from the stromal vascular fraction of adipose tissue and expanded for 2-3 passages. They were then cultured in OEC-CM or SC-CM for 24 hr or 7 days. At each stage, the cells were tested by immunocytochemistry and flow cytometer analysis to evaluate the expression of typical neural markers such as Nestin, PGP 9.5, MAP2, Synapsin I, and GFAP. Results show that both conditioned media induced similar positive effects, as all tested markers were overexpressed, especially at day 7. Overall, an evident trend toward neuronal or glial differentiation was not clearly detectable in many cases. Nevertheless, a higher tendency toward a neuronal phenotype was recognized for OEC-CM (considering MAP2 increases). On the other hand, SC-CM would be responsible for a more marked glial induction (considering GFAP increases). These findings confirm that environmental features can induce ASCs toward a neural differentiation, either as neuronal or glial elements. Rather than supplementing the culture medium by adding chemical agents, a "more physiological" condition was obtained here by means of soluble factors (cytokines/growth factors) likely released by glial cells. This culture strategy may provide valuable information in the development of cell-based therapeutic approaches for pathologies affecting the central/peripheral nervous system.

Physiologically based microenvironment for in vitro neural differentiation of adipose-derived stem cells

The limited capacity of nervous system to promote a spontaneous regeneration and the high rate of neurodegenerative diseases appearance are keys factors that stimulate researches both for defining the molecular mechanisms of pathophysiology and for evaluating putative strategies to induce neural tissue regeneration. In this latter aspect, the application of stem cells seems to be a promising approach, even if the control of their differentiation and the maintaining of a safe state of proliferation should be troubled. Here, we focus on adipose tissue-derived stem cells and we seek out the recent advances on the promotion of their neural differentiation, performing a critical integration of the basic biology and physiology of adipose tissue-derived stem cells with the functional modifications that the biophysical, biomechanical and biochemical microenvironment induces to cell phenotype. The pre-clinical studies showed that the neural differentiation by cell stimulation with growth factors benefits from the integration with biomaterials and biophysical interaction like microgravity. All these elements have been reported as furnisher of microenvironments with desirable biological, physical and mechanical properties. A critical review of current knowledge is here proposed, underscoring that a real advance toward a stable, safe and controllable adipose stem cells clinical application will derive from a synergic multidisciplinary approach that involves material engineer, basic cell biology, cell and tissue physiology.

New insights on Parkinson's disease from differentiation of SH-SY5Y into dopaminergic neurons: An involvement of aquaporin4 and 9

The purpose of this research was to explore the behavior of aquaporins (AQPs) in an in vitro model of Parkinson's disease that is a recurrent neurodegenerative disorder caused by the gradual, progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Because of postmortem studies have provided evidences for oxidative damage and alteration of water flow and energy metabolism, we carried out an investigation about AQP4 and 9, demonstrated in the brain to maintain water and energy homeostasis. As an appropriate in vitro cell model, we used SH-SY5Y cultures and induced their differentiation into a mature dopaminergic neuron phenotype with retinoic acid (RA) alone or in association with phorbol-12-myristate-13-acetate (MPA). The association RA plus MPA provided the most complete and mature neuron phenotype, as demonstrated by high levels of β-Tubulin III, MAP-2, and tyrosine hydroxylase. After validation of cell differentiation, the neurotoxin 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) and H₂O₂ were applied to reproduce a Parkinson's-like stress. The results confirmed RA/MPA differentiated SH-SY5Y as a useful in vitro system for studying neurotoxicity and for using in a MPTP and H₂O₂-induced Parkinson's disease cell model. Moreover, the data demonstrated that neuronal differentiation, neurotoxicity, neuroinflammation, and oxidative stress are strongly correlated with dynamic changes of AQP4 and 9 transcription and transduction. New in vitro and in vivo experiments are needed to confirm these innovative outcomes.

Effects of 12-week supplementation of Citrus bergamia extracts-based formulation CitriCholess on cholesterol and body weight in older adults with dyslipidemia: a randomized, double-blind, placebo-controlled trial

Backgrounds

Recent experiments suggest that Citrus bergamia extracts could benefit people with dyslipidemia and obesity but this needs to be further validated.

Methods

A total of 98 people age-matched older adults (65 years) with elevated blood lipids were enrolled to receive 12-week supplementation of a Citrus bergamia extracts-based formulation (CitriCholess)(n = 48) and placebo (n = 50).

Results

No group differences were found in baseline bodyweight, body mass index (BMI), blood cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and glucose levels. CitriCholess supplementation resulted in lower levels than placebo in TG (1.83 ± 0.92 vs. 1.95 ± 1.34 mmol/L, P = 0.612), TC (5.14 ± 0.98 vs. 5.44 ± 0.77 mmol/L, P = 0.097), and LDL-C (3.13 ± 0.74 vs. 3.43 ± 0.62 mmol/L, P = 0.032). Compared to placebo, CitriCholess also resulted in greater reductions in body weight (−0.604 ± 0.939 vs. 0.06 ± 0.74 kg, P < 0.01), waist circumferences (−0.60 ± 1.349 cm vs. -0.16 ± 1.503 cm, P < 0.01) and BMI (−0.207 ± 0.357 vs. 0.025 ± 0.274, P < 0.01). Additionally, females had a significantly higher level of HDL-C than males. TC was significantly correlated with LDL-C, and to a less degree, with TG. TG was inversely correlated with HDL-C. Body weight and waist circumference were negatively correlated with HDL-C and positively correlated with glucose.

Conclusion

12-week supplementation of CitriCholess could benefit lipid metabolism and weight management in old adults with dyslipidemia.

The Rosiglitazone-Like Effects of Vitexilactone, a Constituent from Vitex trifolia L. in 3T3-L1 Preadipocytes

The increased number of patients with type 2 diabetes (T2D) has become a worldwide problem, and insulin sensitizers such as thiazolidinediones (TZDs) are used as therapeutic agents. We found that extracts of Vitex trifolia L. (V. trifolia), a medicinal plant from Myanmar, induced adipogenesis similar to rosiglitazone (ROS), which is a TZD, in 3T3-L1 preadipocytes. In the present study, we attempted to isolate from V. trifolia those compounds that showed ROS-like effects. Among the extracts of hexane, ethyl acetate, and methanol obtained from V. trifolia, the ethyl acetate extract with the strongest ROS-like effects was purified by various chromatographic methods to obtain three known compounds: vitexilactone (1), vitexicarpin (2) and oleanolic acid (3). Among the isolated compounds, the ROS-like action of 1 was the strongest. The effects of 1 on 3T3-L1 cells during adipogenesis were compared with those of ROS. Both 1 and ROS increased lipid accumulation, the expression of adiponectin and GLUT4 in the cell membrane and decreased both the size of adipocytes and the phosphorylation of IRS-1, ERK1/2 and JNK in 3T3-L1 cells. In contrast, unlike ROS, the induction of proteins involved in lipogenesis was partial. ROS-like effects of 1 in 3T3-L1 cells were suppressed by the addition of bisphenol A diglycidyl ether (BADGE), one of a peroxisome proliferator-activated receptor γ (PPARγ) antagonists, suggesting that the action of 1 on adipocytes is mediated by PPARγ. From the results of the present study, it can be concluded that 1 is a novel insulin sensitizer candidate.

Phenolic compounds apigenin, hesperidin and kaempferol reduce in vitro lipid accumulation in human adipocytes

BACKGROUND

Adipocytes derived from human mesenchymal stem cells (MSCs) are widely used to investigate adipogenesis. Taking into account both the novelty of these MSCs and the scarcity of studies focused on the effects of phenolic compounds, the aim of the present study was to analyze the effect of apigenin, hesperidin and kaempferol on pre-adipocyte and mature adipocytes derived from this type of cells. In addition, the expression of genes involved in TG accumulation was also measured.

METHODS

Pre-adipocytes were cultured from day 0 to day 8 and mature adipocytes for 48 h with the polyphenols at doses of 1, 10 and 25 µM.

RESULTS

Apigenin did not show an anti-adipogenic action. Pre-adipocytes treated with hesperidin and kaempferol showed reduced TG content at the three experimental doses. Apigenin did not modify the expression of the main adipogenic genes (c/ebpβ, c/ebpα, pparγ and srebp1c), hesperidin inhibited genes involved in the three phases of adipogenesis (c/ebpβ, srebp1c and perilipin) and kaempferol reduced c/ebpβ. In mature adipocytes, the three polyphenols reduced TG accumulation at the dose of 25 µM, but not at lower doses. All compounds increased mRNA levels of atgl. Apigenin and hesperidin decreased fasn expression. The present study shows the anti-adipogenic effect and delipidating effects of apigenin, hesperidin and kaempferol in human adipocytes derived from hMSCs. While hesperidin blocks all the stages of adipogenesis, kaempferol only inhibits the early stage. Regarding mature adipocytes, the three compounds reduce TG accumulation by activating, at least in part, lipolysis, and in the case of hesperidin and apigenin, also by reducing lipogenesis.

CONCLUSIONS

The present study shows for the first time the anti-adipogenic effect and delipidating effect of apigenin, hesperidin and kaempferol in human adipocytes derived from MSCs for the first time.

Aquaporin1 and 3 modification as a result of chondrogenic differentiation of human mesenchymal stem cell

Chondrocytes are cells of articular cartilage particularly sensitive to water transport and ionic and osmotic changes from extracellular environment and responsible for the production of the synovial fluid. Aquaporins (AQPs) are a family of water and small solute transport channel proteins identified in several tissues, involved in physiological pathways and in manifold human diseases. In a recent period, AQP1 and 3 seem to have a role in metabolic water regulation in articular cartilage of load bearing joints. The aim of this study was to examine the levels of AQP1 and 3 during the chondrogenic differentiation of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT). For the determination of chondrogenic markers and AQPs levels, glycosaminoglycans (GAGs) quantification, immunocytochemistry, RT-PCR, and Western blot were used after 0, 7, 14, 21, and 28 days from the start of differentiation. At 21 days, chondrocytes derived from AT-MSCs were able to produce augmented content of GAGs and significant quantity of SOX-9, lubricin, aggrecan, and collagen type II, suggesting hyaline cartilage formation, in combination with an increase of AQP3 and AQP1. However, while AQP1 level decreased after 21 days; AQP3 reached higher values at 28 days. The expression of AQP1 and 3 is a manifestation of physiological adaptation of functionally mature chondrocytes able to respond to the change of their internal environment influenced by extracellular matrix. The alteration or loss of expression of AQP1 and 3 could contribute to destruction of chondrocytes and to development of cartilage damage.

Pyrocincholic acid 3β-O-β-D-quinovopyranosyl-28-O-β-D-glucopyranoside suppresses adipogenesis and regulates lipid metabolism in 3T3-L1 adipocytes

Obesity is crucially involved in many metabolic diseases, such as type 2 diabetes, cardiovascular disease and cancer. Regulating the number or size of adipocytes has been suggested to be a potential treatment for obesity. In this study, we investigated the effect of pyrocincholic acid 3β-O-β-D-quinovopyranosyl-28-O-β-D-glucopyranoside (PAQG), a 27-nor-oleanolic acid saponin extracted from Metadina trichotoma, on adipogenesis and lipid metabolism in 3T3-L1 adipocytes. The 3T3-L1 pre-adipocytes were incubated with vehicle or PAQG for 6 days in differentiation process. PAQG significantly reduced the adipogenesis, adiponectin secretion and the expression level of key transcription factors related to adipogenesis, such as PPARγ, C/EBPβ, C/EBPα, and FABP4. Moreover, PAQG increased the levels of FFA and glycerol in medium and reduced TG level in mature adipocytes. Interestingly, PAQG not only promoted the activation of AMPK and genes involved in fatty oxidation including PDK4 and CPT1a, but also inhibited those genes involved in fatty acid biosynthesis, such as SREBP1c, FAS, ACCα and SCD1. In conclusion, PAQG inhibits the differentiation and regulates lipid metabolism of 3T3-L1 cells via AMPK pathway, suggesting that PAQG may be a novel and promising natural product for the treatment of obesity and hyperlipidemia.

A Limonoid Kihadanin B from Immature Citrus unshiu Peels Suppresses Adipogenesis through Repression of the Akt-FOXO1-PPARγ Axis in Adipocytes

Citrus limonoids are secondary metabolites and exhibit a variety of biological activities. In this study, we elucidated the suppression of adipogenesis by a Citrus limonoid kihadanin B and determined its molecular mechanism in mouse 3T3-L1 adipocytes. Kihadanin B was purified from the peels of immature Citrus unshiu by HPLC, and its chemical structure was determined by NMR and mass spectrometry. Kihadanin B reduced the lipid accumulation with the reduction of the expression levels of the adipogenic and lipogenic genes, but did not affect lipolysis in adipocytes. Phosphorylation levels of Akt and a forkhead transcriptional factor, FOXO1, a repressor of PPARγ, were lowered by kihadanin B. Furthermore, kihadanin B increased the binding level of FOXO1 to the PPARγ gene promoter in adipocytes. These results indicate that a Citrus limonoid kihadanin B repressed the adipogenesis by decreasing lipid accumulation through the suppression of the Akt-FOXO1-PPARγ axis in 3T3-L1 adipocytes.

Potential Therapeutic Applications of Adipose-Derived Mesenchymal Stem Cells

Stem cells are subdivided into two main categories: embryonic and adult stem cells. In principle, pluripotent embryonic stem cells might differentiate in any cell types of the organism, whereas the potential of adult stem cells would be more restricted. Although adult stem cells from bone marrow have been initially the most extensively studied, those derived from human adipose tissue have been lately more widely investigated, because of several advantages. First, they can be easily obtained in large amounts from subcutaneous adipose tissue, with minimal pain and morbidity for the patients during harvesting. In addition, they feature low immunogenicity and can differentiate not only in cells of mesodermal lineage (adipocytes, osteoblasts, chondrocytes and muscle cells), but also in cells of other germ layers, such as neural or epithelial cells. As their multilineage differentiation capabilities are increasingly highlighted, their possible use in cell-based regenerative medicine is now broadly explored. In fact, starting from in vitro observations, many studies have already entered the preclinical and clinical phases. In this review, because of our main scientific interest, adipogenic, osteogenic, chondrogenic, and neurogenic differentiation abilities of adipose-derived mesenchymal stem cells, as well as their possible therapeutic applications, are chiefly focused. In addition, their ability to differentiate toward muscle, epithelial, pancreatic, and hepatic cells is briefly reported.