N-Acetylcysteine (NAC) Ameliorates Lipid-Related Metabolic Dysfunction in Bone Marrow Stromal Cells-Derived Adipocytes

Raffaele, Marco; Barbagallo, Ignazio; Licari, Maria; Carota, Giuseppe; Sferrazzo, Giuseppe; Spampinato, Mariarita; Sorrenti, Valeria; Vanella, Luca

doi:https://doi.org/10.1155/2018/5310961

Evidence-Based Complementary and Alternative Medicine

On this page

Abstract Introduction Methods Results Discussion Data Availability Conflicts of Interest Authors’ Contributions References Copyright Related Articles

Research Article | Open Access

Volume 2018 | Article ID 5310961 | https://doi.org/10.1155/2018/5310961

N-Acetylcysteine (NAC) Ameliorates Lipid-Related Metabolic Dysfunction in Bone Marrow Stromal Cells-Derived Adipocytes

Marco Raffaele,¹Ignazio Barbagallo,¹Maria Licari,¹Giuseppe Carota,¹Giuseppe Sferrazzo,¹Mariarita Spampinato,¹Valeria Sorrenti,¹and Luca Vanella¹

Academic Editor: Fatima Martel

Received26 Jun 2018

Accepted27 Sept 2018

Published17 Oct 2018

Abstract

Recent experimental data suggest that fatty acids and lipotoxicity could play a role in the initiation and evolution of metabolic bone diseases such as osteoporosis. A functional bone marrow adipose tissue (BMAT) may provide support to surrounding cells and tissues or may serve as a lipid reservoir that protects skeletal osteoblasts from lipotoxicity. The present study examined the effect of N-acetylcysteine (NAC), a powerful antioxidant and precursor of glutathione, commonly used to treat chronic obstructive pulmonary disease, on triglycerides accumulation in bone marrow stromal cells-derived adipocytes. Quantification of Oil Red O stained cells showed that lipid droplets decreased following NAC treatment. Additionally, exposure of bone marrow stromal cells (HS-5) to NAC increased adiponectin, PPARγ, HO-1, and SIRT-1 and increased beta-oxidation markers such as PPARα and PPARδ mRNA levels. As there is now substantial interest in alternative medicine, the observed therapeutic value of NAC should be taken into consideration in diabetic patients.

1. Introduction

Obesity, diabetes, and metabolic syndrome are linked to abnormal bone homeostasis. The balance between bone formation and resorption is compromised in diabetes, which may contribute to the high risk of fractures in diabetic patients [1–4].

Osteoporosis is a metabolic bone disease associated with a dysregulated bone remodeling resulting from an alteration of the balance between bone formation and bone resorption but although the association between osteoporosis and type I diabetes (T1D) is well established [5], the reported association between osteoporosis and type II diabetes (T2D) is less clear. Chronic hyperglycemia, observed in T2D, accelerates the nonenzymatic process of protein glycosylation, resulting in the formation and accumulation of advanced glycation end-products which contribute to skeletal fragility [6, 7].

Accumulative evidence has indicated that T2D is associated with a reduced bone turnover and consequently a poor bone quality caused by lower levels of bone formation and resorption [8, 9].

Interestingly, an increased bone marrow adiposity (BMA) has been reported in T1D and T2D; however, in T1D, it was observed a decrease in bone mass, whereas T2D is characterized by no change or higher bone mass and paradoxically increased risk of bone fractures [10, 11]. In the last decade, there has been increasing interest in the formation, function, and potential endocrine roles of bone marrow adipose tissue (BMAT) [12–14].

BMAT develops postnatally and accounts for 50–70% of bone marrow volume in healthy adult humans. Historically BMAT was considered as an inert type of fat which accumulates in the bone marrow to fill empty space. Marrow adipocytes are no more regarded as simple filling cells, and their involvement in bone physiopathology is now considered. Indeed, BMAT can be considered a functional organ that can undergo pathologic changes and respond to diseases [15].

Furthermore, several studies support the notion that BMAT is significantly associated with skeletal health. In vitro studies have shown that adipocytes may directly influence osteoblast and osteoclast differentiation and function, through secretion of adipokines and free fatty acids, suggesting a direct effect of BMAT on bone turnover. BMAT adipocytes are situated in a unique microenvironment, surrounded by hematopoietic and skeletal lineage cells. Hyperglycemia has emerged as a major issue that threatens health and causes vascular and organ dysfunction. Recent reports indicate that hyperglycemia impairs bone marrow hematopoietic function and alters hematopoietic niche [16].

These observations suggest that BMAT may function to provide support to surrounding cells and tissues or may serve as a lipid reservoir, a storage site that protects skeletal osteoblasts from lipotoxicity or may exert systemic effects [17–19].

These findings have raised much interest in the potential role of BMAT supporting the concept that BMAT has an endocrine/paracrine function modulating marrow environment supporting bone remodeling and that this function is under similar regulatory axes as in peripheral adipose tissue.

Changes in bone fat metabolism may contribute to an increase in oxidative stress and in oxidized lipids associated with increased local inflammatory responses, resistance to anabolic effects of Wnt signaling, and osteoporotic bone formation. Bone mineral density and biochemical markers of bone turnover are adversely affected in individuals with diabetes. Indeed, glucose intolerance and saturated fatty acids are associated with the attenuation of bone remodeling and turnover in animal models of diet-induced obesity and diabetes [20, 21].

Increasing evidence confirmed that oxidative stress plays a role in the triggering of bone disease associated with diabetes [22].

Moreover, levels of reduced glutathione (GSH), which represents the major intracellular reducing molecule, are decreased in the bone marrow after induction of diabetes.

N-acetylcysteine (NAC) is a thiol compound that stimulates glutathione-S-transferase activity; it acts as a scavenger of free radicals and as an antioxidant by restoring the pool of intracellular GSH. NAC has been commonly used to treat chronic obstructive pulmonary disease [23, 24] but in addition to its antioxidant and anti-inflammatory properties, there is a growing interest in the beneficial effects of NAC for treating metabolic disorders. It has been shown that NAC supplementation suppresses fructose and high-sucrose diet-induced hyperglycemia and hyperinsulinemia and improves peripheral insulin sensitivity [25–27].

Additionally, Yamada et al. demonstrated that NAC markedly promoted the differentiation of osteoblastic cells and accelerated bone regeneration [28]. Despite some data demonstrating that NAC inhibits murine preadipocyte differentiation [29], its anti-inflammatory effects on human mature and hypertrophic bone marrow adipocytes are not known.

The goal of the present study was to determine whether NAC treatment affect lipid metabolism and triglycerides accumulation in bone marrow stromal cells-derived adipocytes.

2. Material and Methods

2.1. Differentiation of Human BMSC into Adipocytes

HS-5, human bone marrow stromal cells, were purchased from American Type Culture Collection (Rockville, MD, USA). After thawing, HS-5 cells were resuspended in DMEM, supplemented with 10% heat inactivated fetal bovine serum (FBS, Invitrogen, Carlsbad, CA, USA) and 1% antibiotic/antimycotic solution (Invitrogen), and plated in a 75 cm² flask at a density of 1 to 2 × 10⁴ cells. The medium was replaced with adipogenic medium, and the cells were cultured for additional 19 days. The adipogenic media (Lonza, Basel, SW) consisted of complete culture medium supplemented with DMEM-high glucose (4.5 g/L), 10% (v/v) FBS, 10 μg/ml insulin, 0.5 mM dexamethasone (Sigma-Aldrich, St. Louis, MO), 0.5 mM isobutylmethylxanthine (Sigma-Aldrich, St. Louis, MO), and 0.1 mM indomethacin (Sigma– Aldrich, St. Louis, MO). Medium was changed every 3 days. In our experiments human BMSCs were cultured in the presence of NAC (10 mM) which was added once for the last 3 days of differentiation.

2.2. Cell Viability Assay

HS-5 cells were seeded at a concentration of 2 × 10⁵ cells per well of a 96-well, flat-bottomed 200 μl microplate. Cells were incubated at 37°C in a 5% CO₂ humidified atmosphere and cultured for 24 h in the presence and absence of different concentrations (1, 10, and 100 mM) of NAC. Four hours before the end of the treatment time, 20 μl of 0.5% 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) in phosphate buffered saline (PBS) was added to each microwell. After incubation with the reagent, the supernatant was removed and replaced with 100 μl DMSO. The amount of formazan produced is proportional to the number of viable cells present. The optical density was measured using a microplate spectrophotometer reader (Thermo Labsystems Multiskan Italy) at λ = 570 nm.

2.3. Free Radical Scavenging Activity

The free radical scavenging activity of NAC was evaluated using the DPPH (2,2-diphenyl-1-picrylhydrazyl) test. An aliquot of MeOH solution containing NAC 10 mM was added to a daily prepared methanol DPPH solution (final concentration 0.1 mM). The optical density change at 517 nm was measured, 20 min after the initial mixing, using a microplate spectrophotometer reader (Thermo Labsystems Multiskan Italy). Rutin (50μM) was used as reference. The scavenging activity was measured as the decrease in absorbance of the samples versus DPPH standard solution. The results were obtained from the average of three independent experiments and are reported as mean radical scavenging activity percentage (%) ± SD.

2.4. Measurement of HO Enzymatic Activity in HS-5 Cell Line

Total HO activity in the cell lysate was determined by measuring the bilirubin formation using the difference in absorbance at 464–530 nm as previously described [30].

Reaction mixtures (500 μL) consisted of 20 mM Tris-HCl, pH 7.4, (1 mg/mL) cell lysate, 2 mg/mL biliverdin reductase, 1 mM NADPH, 2 mM glucose 6-phosphate (G6P), 1 U G6P dehydrogenase, and 25 μM hemin. Incubations were carried out for 1 h at 37°C in a circulating water bath in the dark. Reactions were stopped by adding 1 volume of chloroform. After recovering the chloroform phase, the amount of bilirubin formed was measured with a double-beam spectrophotometer as OD464-530 nm (extinction coefficient, 40 mM/cm-1 for bilirubin). One unit of the enzyme was defined as the amount of enzyme catalyzing the formation of 1 nmol of bilirubin/ mg protein/h.

2.5. Oil Red O Staining

Staining was performed using 0.21% Oil Red O in 100% isopropanol (Sigma-Aldrich, St. Louis, MO, USA). Briefly, adipocytes were fixed in 10% formaldehyde, stained with Oil Red O for 10 minutes, and rinsed with 60% isopropanol (Sigma-Aldrich), and the Oil Red O was eluted by adding 100% isopropanol for 10 minutes and the optical density (OD) measured at 490 nm, for 0.5 sec reading. Lipid droplets accumulation was examined by using inverted multichannel LED fluorescence microscope (Evos, Life Technologies, NY).

2.6. RNA Extraction and qRT-PCR

RNA was extracted by Trizol reagent (Invitrogen, Carlsbad, CA, USA). First strand cDNA was then synthesized with Applied Biosystem (Foster City, CA, USA) reverse transcription reagent.

Quantitative Real-Time PCR was performed in 7900HT Fast Real-Time PCR System Applied Biosystems using the SYBR Green PCR MasterMix (Life Technologies). The primer sequences used are shown in Table 1.

The specific PCR products were detected by the fluorescence of SYBR Green, the double stranded DNA binding dye. The relative mRNA expression level was calculated by the threshold cycle (Ct) value of each PCR product and normalized with that of GAPDH by using comparative method.

2.7. Statistical Analyses

Statistical significance (p<0.05) of differences between experimental groups was determined by the Fisher method for analysis of multiple comparisons. For comparison between treatment groups, the null hypothesis was tested by either single-factor analysis of variance (ANOVA) for multiple groups or the unpaired-test for two groups, and the data are presented as mean ± standard deviation (SD).

3. Results

3.1. Viability Assessment

The absence of cytotoxicity of NAC was assessed by the MTT assay, a widely recognized in vitro preliminary screening able to individuate time and concentration-dependent toxic effect on mammalian cell vitality and growth. After a 24 h incubation period to various concentrations of NAC (1, 10, 100 mM), MTT assay (Figure 1) did not reveal any cytotoxic effect of NAC against HS-5 bone marrow stromal cells.

3.2. Antioxidant Activity of NAC

Because of its odd electron, DPPH gives a strong absorption band at 517 nm in visible spectroscopy (deep violet color). As this electron becomes paired off in the presence of a free radical scavenger, the absorption vanishes and the resulting decolorization is stoichiometric with respect to the number of electrons taken up. As shown in Figure 2(a), NAC exhibited DPPH free radical scavenging activity in a cell-free system. As DPPH is a synthetic radical, we also investigated the antioxidant capacity of NAC by measuring heme oxygenase derived bilirubin production in a cellular system. Under our experimental conditions, exposed HS-5 cells to 10 mM NAC for 24 hr showed a significant increase in heme oxygenase activity compared to untreated control cells (Figure 2(b)).

(a)

(b)

3.3. Effect of NAC on Adipocyte Lipid Metabolism

We examined the effect of NAC on lipid accumulation after 19 days, using standard culture conditions by measuring Oil Red O stained lipid droplet area (Figure 3). Quantification of Oil Red O stained cells showed that lipid droplets decreased following NAC treatment. In addition to that, the expression of SIRT-1 and the antioxidant enzyme HO-1 in the presence of NAC significantly increased after 19 days (Figure 4), which was consistent with our previous results showing HO-1 induction decreased lipid droplets [31–33].

To further examine the mechanism by which NAC regulates lipid metabolism, we measured DGAT1, FABP4, FAS, PPARγ, PPARα, PPARδ, and adiponectin mRNA levels in adipocytes (Figures 4 and 5). Interestingly, as seen in Figure 5, DGAT1 mRNA expression was found to be significantly decreased in mature adipocytes compared to control cells and this effect was reversed by concurrent treatment with NAC. Our results further demonstrated that the expression of PPARγ was significantly downregulated after 19 days of differentiation and this effect was negated by the treatment with NAC. Also our data showed that FAS levels were not significantly altered in all groups but FABP4 levels were increased by NAC treatment. Further, our results on beta-oxidation markers, such as PPARα and PPARδ, showed that NAC treatment increased both mRNA levels.

Adipose cell enlargement is associated with increased secretion of cytokines, which impairs the differentiation of preadipocytes and reduces adiponectin secretion. We examined the levels of IL-6 in NAC-treated HS-5 and found that IL-6 levels were significantly decreased. In contrast, adiponectin levels were increased following NAC treatment when compared to controls at day 19 (Figure 4).

4. Discussion

Although there is extensive literature on the role of visceral, subcutaneous, and brown adipose depots in the development of insulin resistance and type II diabetes, few studies have investigated the function of BMAT as an adipose storage organ [34].

Studies are underway to examine the role of impaired glucose metabolism and its associated hyperglycemia and hyperinsulinemia on the biological functions of BMSC [35].

Evidence collected from animal and human studies indicate that impairment in adipose tissue metabolism correlates with decreased bone quality.

A recent clinical study demonstrated very clearly that adipocyte size is associated with vertebral fractures supporting the hypothesis that large adipocytes are inflamed and produce several proinflammatory cytokines which affect bone quality as well as progenitor cells [36–38].

Currently, there are several ongoing studies examining the potential positive effects of BMAT on bone mass. A recent and innovative hypothesis suggest that BMAT can be targeted to treat bone disease since BMAT could support bone formation and remodeling. Marrow fat may participate in lipid metabolism by clearing and storing circulating triglycerides, thereby providing a localized energy reservoir for osteogenesis during bone fracture healing.

Recent experimental data suggest that FA and lipotoxicity could play a role in the initiation and/or evolution of metabolic bone diseases such as osteoporosis [39].

Although in small quantities relatively to white adipose tissue, marrow adipocytes produce leptin and adiponectin. Thus, it is reasonable to believe that BMAT has a local endocrine/paracrine function modulating marrow environment supporting bone remodeling and that this function is under similar regulatory axes as in peripheral fat.

Although NAC is a well-known thiol compound used in chronic obstructive pulmonary disease because it possesses a free sulfhydryl group through which it reduces disulfide bonds conferring antioxidant effects, NAC possess other beneficial effects on glucose and lipid metabolism [40].

Yang et al. reported that NAC administration partially reduces plasma triglycerides, total cholesterol, and LDL levels while increasing the HDL level in rats fed a high fat diet [41].

Short-term NAC administration in drinking water prevented high-sucrose induced weight gain and dyslipidemia. Collectively, these studies show that NAC is capable of restoring dysregulated glucose and lipid metabolism, suggesting its potential application in metabolic disturbance.

Our results demonstrate that NAC exhibits an interesting antioxidant activity in cell-free and in cell systems. It was able to quench the synthetic DPPH radical and exhibited an increase in heme oxygenase activity as shown by rise in bilirubin formation.

In adipose tissues, induction of HO-1 has been shown to reduce body weight, decrease proinflammatory cytokines, and increase PGC-1α mediated thermogenesis, thereby increasing energy uptake and the stimulation of mitochondrial FA oxidation [42–45].

To investigate the effects of NAC on human bone marrow adipocytes, HS-5 cells were exposed to NAC added to the differentiation medium for three days. HS-5 accumulated lipid droplets following exposure to the differentiation medium; however, consistent with previous reports on murine cells, lipid accumulation in the presence of NAC was reduced compared to untreated cells. To assess whether the reduced lipid droplets formation, induced by NAC, could be explained by altered activation of typical key markers of mature adipocytes, PPARγ, DGAT1, FABP4, FAS, and adiponectin levels were investigated. Figures 4 and 5 show that NAC increases DGAT1, FABP4, and adiponectin levels. The latter represents a hormone with insulin-sensitizing, anti-inflammatory, and antiapoptotic functions released by functional healthy adipocytes.

PPARγ represents the master regulator of adipogenesis and increased PPARγ signaling in mature adipocytes is linked to improved insulin sensitivity [46]. Recently, it has been shown that specific modulators of PPARγ activity, specifically those which protect Ser112 phosphorylation, induce beige-like profile in BMAT and in peripheral white adipose tissue and have either no or positive effect on bone, in contrast to thiazolidinediones which dephosphorylate Ser112 and have negative effects on bone structure [47, 48]. Our unexpected results on DGAT1 might support the concept that the function of DGAT1-mediated FA reesterification is not to preserve TG mass but instead protects the endoplasmic reticulum from lipotoxic stress and associated adipose tissue inflammation. Indeed, DGAT levels are decreased in mature adipocytes (Figure 3), suggesting that hypertrophic adipocytes lose the esterification function essential to reesterificate free fatty acids which represent the main cause of insulin resistance. In support of that, Dgat1-deficient mice have abnormal bone architecture and increased levels of osteoclast differentiation [49]. In addition to that, low FABP4 expression in adipose tissue could lead to less free fatty acids transport to β-oxidation, resulting in a fatty acids accumulation, which may exceed the adipose tissue storage capacity, resulting in excess fat “overspilled” to nonadipose tissues [50].

Further beneficial effects mediated by NAC are associated with an increase in mRNA levels of genes responsible for fatty acid oxidation and HO-1 induction. Indeed, NAC cause a strong induction of PPARα (8-fold increase) and PPARδ (15-fold increase) compared to untreated cells. These data support the beneficial interaction between bilirubin and PPAR alpha [51].

Several studies demonstrated that bilirubin treatment decreased body weight and body fat and increased lean body mass in wild-type but not in PPARα knockout mice [52, 53].

In conclusion, we show here in a cell-based model of adipogenesis that NAC entails reduced lipid accumulation comprising smaller healthier adipocytes, reduced inflammation, and improved adipokine secretion (Figure 6). These results provide direct evidence to support the use of NAC supplementation as an effective drug metabolic disorders.

Data Availability

The data used to support the findings of this study are available from the corresponding author upon request.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Authors’ Contributions

Marco Raffaele and Ignazio Barbagallo contributed equally to this work.

References

J. Alblowi, R. A. Kayal, M. Siqueria et al., “High Levels of Tumor Necrosis Factor-α Contribute to Accelerated Loss of Cartilage in Diabetic Fracture Healing,” The American Journal of Pathology, vol. 175, no. 4, pp. 1574–1585, 2009.
View at: Publisher Site | Google Scholar
V. Carnevale, E. Romagnoli, and E. D'Erasmo, “Skeletal involvement in patients with diabetes mellitus,” Diabetes/Metabolism Research and Reviews, vol. 20, no. 3, pp. 196–204, 2004.
View at: Publisher Site | Google Scholar
L. C. Hofbauer, C. C. Brueck, S. K. Singh, and H. Dobnig, “Osteoporosis in patients with diabetes mellitus,” Journal of Bone and Mineral Research, vol. 22, no. 9, pp. 1317–1328, 2007.
View at: Publisher Site | Google Scholar
R. A. Kayal, D. Tsatsas, M. A. Bauer et al., “Diminished bone formation during diabetic fracture healing is related to the premature resorption of cartilage associated with increased osteoclast activity,” Journal of Bone and Mineral Research, vol. 22, no. 4, pp. 560–568, 2007.
View at: Publisher Site | Google Scholar
T. Forst, A. Pfutzner, P. Kann et al., “Peripheral osteopenia in adult patients with insulin-dependent diabetes mellitus,” Diabetic Medicine, vol. 12, no. 10, pp. 874–879, 1995.
View at: Publisher Site | Google Scholar
W. Yan and X. Li, “Impact of diabetes and its treatments on skeletal diseases,” Frontiers of Medicine in China, vol. 7, no. 1, pp. 81–90, 2013.
View at: Publisher Site | Google Scholar
Y. Cheng, S. Yang, J. Wang et al., “Irbesartan attenuates advanced glycation end products-mediated damage in diabetes-associated osteoporosis through the AGEs/RAGE pathway,” Life Sciences, vol. 205, pp. 184–192, 2018.
View at: Publisher Site | Google Scholar
I. I. de Liefde, M. van der Klift, C. E. D. H. de Laet, P. L. A. van Daele, A. Hofman, and H. A. P. Pols, “Bone mineral density and fracture risk in type-2 diabetes mellitus: the Rotterdam Study,” Osteoporosis International, vol. 16, no. 12, pp. 1713–1720, 2005.
View at: Publisher Site | Google Scholar
C. P. Sanches, A. G. Vianna, and F. d. Barreto, “The impact of type 2 diabetes on bone metabolism,” Diabetology & Metabolic Syndrome, vol. 9, no. 1, 2017.
View at: Publisher Site | Google Scholar
M. J. Devlin and C. J. Rosen, “The bone-fat interface: Basic and clinical implications of marrow adiposity,” The Lancet Diabetes & Endocrinology, vol. 3, no. 2, pp. 141–147, 2015.
View at: Publisher Site | Google Scholar
M. Tencerova and M. Kassem, “The Bone Marrow-Derived Stromal Cells: Commitment and Regulation of Adipogenesis,” Frontiers in Endocrinology, vol. 7, p. 127, 2016.
View at: Publisher Site | Google Scholar
W. P. Cawthorn and E. L. Scheller, “Editorial: Bone Marrow Adipose Tissue: Formation, Function, and Impact on Health and Disease,” Front Endocrinol (Lausanne), vol. 8, p. 112, 2007.
View at: Publisher Site | Google Scholar
B. Lecka-Czernik, S. Baroi, L. A. Stechschulte, and A. S. Chougule, “Marrow Fat—a New Target to Treat Bone Diseases?” Current Osteoporosis Reports, vol. 16, no. 2, pp. 123–129, 2018.
View at: Publisher Site | Google Scholar
B. Lecka-Czernik, L. A. Stechschulte, P. J. Czernik, S. B. Sherman, S. Huang, and A. Krings, “Marrow adipose Tissue: Skeletal location, sexual dimorphism, and response to sex steroid deficiency,” Frontiers in Endocrinology, vol. 8, p. 188, 2017.
View at: Google Scholar
K. J. Suchacki and W. P. Cawthorn, “Molecular Interaction of Bone Marrow Adipose Tissue with Energy Metabolism,” Current Molecular Biology Reports, vol. 4, no. 2, pp. 41–49, 2018.
View at: Publisher Site | Google Scholar
F. Ferraro, S. Lymperi, S. Méndez-Ferrer et al., “Diabetes impairs hematopoietic stem cell mobilization by altering niche function,” Science Translational Medicine, vol. 3, no. 104, 2011.
View at: Publisher Site | Google Scholar
D. Mattiucci, G. Maurizi, V. Izzi et al., “Bone marrow adipocytes support hematopoietic stem cell survival,” Journal of Cellular Physiology, vol. 233, no. 2, pp. 1500–1511, 2018.
View at: Publisher Site | Google Scholar
E. L. Scheller, W. P. Cawthorn, A. A. Burr, M. C. Horowitz, and O. A. MacDougald, “Marrow Adipose Tissue: Trimming the Fat,” Trends in Endocrinology & Metabolism, vol. 27, no. 6, pp. 392–403, 2016.
View at: Publisher Site | Google Scholar
P. Hardouin, T. Rharass, and S. Lucas, “Bone Marrow Adipose Tissue: To Be or Not To Be a Typical Adipose Tissue?” Frontiers in Endocrinology, vol. 7, 2016.
View at: Publisher Site | Google Scholar
R. L. Corwin, T. J. Hartman, S. A. Maczuga, and B. I. Graubard, “Dietary saturated fat intake is inversely associated with bone density in humans: Analysis of NHANES III,” Journal of Nutrition, vol. 136, no. 1, pp. 159–165, 2006.
View at: Publisher Site | Google Scholar
T. S. Orchard, J. A. Cauley, G. C. Frank et al., “Fatty acid consumption and risk of fracture in the Women's Health Initiative,” American Journal of Clinical Nutrition, vol. 92, no. 6, pp. 1452–1460, 2010.
View at: Publisher Site | Google Scholar
M. Bacevic, B. Brkovic, A. Albert, E. Rompen, R. P. Radermecker, and F. Lambert, “Does Oxidative Stress Play a Role in Altered Characteristics of Diabetic Bone? A Systematic Review,” Calcified Tissue International, vol. 101, no. 6, pp. 553–563, 2017.
View at: Publisher Site | Google Scholar
L. Vanella, G. L Volti I, A. Distefano et al., “A new antioxidant formulation reduces the apoptotic and damaging effect of cigarette smoke extract on human bronchial epithelial cells,” European Review for Medical and Pharmacological Sciences, vol. 21, no. 23, pp. 5478–5484.
View at: Google Scholar
M. G. Matera, L. Calzetta, and M. Cazzola, “Oxidation pathway and exacerbations in COPD: the role of NAC,” Expert Review of Respiratory Medicine, vol. 10, no. 1, pp. 89–97, 2016.
View at: Publisher Site | Google Scholar
G. A. Souza, G. X. Ebaid, F. R. Seiva et al., “N-acetylcysteine an allium plant compound improves high-sucrose diet-induced obesity and related effects,” Evidence-Based Complementary and Alternative Medicine, vol. 2011, Article ID 643269, 7 pages, 2011.
View at: Publisher Site | Google Scholar
P. V. Dludla, S. C. Dias, N. Obonye, R. Johnson, J. Louw, and B. B. Nkambule, “A Systematic Review on the Protective Effect of N-Acetyl Cysteine Against Diabetes-Associated Cardiovascular Complications,” American Journal of Cardiovascular Drugs, vol. 18, no. 4, pp. 283–298, 2018.
View at: Publisher Site | Google Scholar
J. Zheng, X. Yuan, C. Zhang et al., “N-Acetyl-Cysteine Alleviates Gut Dysbiosis and Glucose Metabolic Disorder in High-Fat Diet-Induced Mice,” Journal of Diabetes, 2018.
View at: Google Scholar
M. Yamada, N. Tsukimura, T. Ikeda et al., “N-acetyl cysteine as an osteogenesis-enhancing molecule for bone regeneration,” Biomaterials, vol. 34, no. 26, pp. 6147–6156, 2013.
View at: Publisher Site | Google Scholar
P. Calzadilla, M. Gómez-Serrano, E. García-Santos et al., “N-Acetylcysteine affects obesity-related protein expression in 3T3-L1 adipocytes,” Redox Report, vol. 18, no. 6, pp. 210–218, 2013.
View at: Publisher Site | Google Scholar
V. Pittala, L. Vanella, L. Salerno et al., “Novel Caffeic Acid Phenethyl Ester (Cape) Analogues as Inducers of Heme Oxygenase-1,” Current Pharmaceutical Design, vol. 23, no. 18, 2017.
View at: Publisher Site | Google Scholar
L. Vanella, K. Sodhi, D. H. Kim et al., “Increased heme-oxygenase 1 expression in mesenchymal stem cell-derived adipocytes decreases differentiation and lipid accumulation via upregulation of the canonical Wnt signaling cascade,” Stem Cell Research & Therapy, vol. 4, no. 2, article 28, 2013.
View at: Publisher Site | Google Scholar
L. Vanella, C. Sanford, D. H. Kim, N. G. Abraham, and N. Ebraheim, “Oxidative Stress and Heme Oxygenase-1 Regulated Human Mesenchymal Stem Cells Differentiation,” International Journal of Hypertension, vol. 2012, Article ID 890671, 10 pages, 2012.
View at: Publisher Site | Google Scholar
L. Vanella, D. Tibullo, J. Godos et al., “Caffeic Acid Phenethyl Ester Regulates PPAR's Levels in Stem Cells-Derived Adipocytes,” PPAR Research, vol. 2016, Article ID 7359521, 13 pages, 2016.
View at: Publisher Site | Google Scholar
R. Terjung, Comprehensive Physiology, John Wiley & Sons, Inc., Hoboken, NJ, USA, 2011.
J. Wei, M. Ferron, C. J. Clarke et al., “Bone-specific insulin resistance disrupts whole-body glucose homeostasis via decreased osteocalcin activation,” The Journal of Clinical Investigation, vol. 124, no. 4, pp. 1–13, 2014.
View at: Publisher Site | Google Scholar
J. Paccou, G. Penel, C. Chauveau, B. Cortet, and P. Hardouin, “Marrow adiposity and bone: Review of clinical implications,” Bone, 2018.
View at: Google Scholar
D. H. Kim, L. Vanella, K. Inoue et al., “Epoxyeicosatrienoic acid agonist regulates human mesenchymal stem cell-derived adipocytes through activation of HO-1-pAKT signaling and a decrease in PPARγ,” Stem Cells and Development, vol. 19, no. 12, pp. 1863–1873, 2010.
View at: Publisher Site | Google Scholar
K. M. Beekman, A. G. Veldhuis-Vlug, M. den Heijer et al., “The effect of raloxifene on bone marrow adipose tissue and bone turnover in postmenopausal women with osteoporosis,” Bone, 2017.
View at: Google Scholar
K. Gunaratnam, C. Vidal, J. M. Gimble, and G. Duque, “Mechanisms of palmitate-induced lipotoxicity in human osteoblasts,” Endocrinology, vol. 155, no. 1, pp. 108–116, 2014.
View at: Publisher Site | Google Scholar
Y. Ma, M. Gao, and D. Liu, “N-acetylcysteine Protects Mice from High Fat Diet-induced Metabolic Disorders,” Pharmaceutical Research, vol. 33, no. 8, pp. 2033–2042, 2016.
View at: Publisher Site | Google Scholar
R. Yang, G. Le, A. Li, J. Zheng, and Y. Shi, “Effect of antioxidant capacity on blood lipid metabolism and lipoprotein lipase activity of rats fed a high-fat diet,” Nutrition Journal , vol. 22, no. 11-12, pp. 1185–1191, 2006.
View at: Publisher Site | Google Scholar
S. P. Singh, I. Grant, A. Meissner, A. Kappas, and N. G. Abraham, “Ablation of adipose-HO-1 expression increases white fat over beige fat through inhibition of mitochondrial fusion and of PGC1α in female mice,” Hormone Molecular Biology and Clinical Investigation, vol. 31, no. 1, 2017.
View at: Publisher Site | Google Scholar
S. P. Singh, J. Schragenheim, J. Cao, J. R. Falck, N. G. Abraham, and L. Bellner, “PGC-1 alpha regulates HO-1 expression, mitochondrial dynamics and biogenesis: Role of epoxyeicosatrienoic acid,” Prostaglandins & Other Lipid Mediators, vol. 125, pp. 8–18, 2016.
View at: Publisher Site | Google Scholar
S. P. Singh, L. Bellner, L. Vanella et al., “Downregulation of PGC-1alpha Prevents the Beneficial Effect of EET-Heme Oxygenase-1 on Mitochondrial Integrity and Associated Metabolic Function in Obese Mice,” Journal of Nutrition and Metabolism, vol. 2016, Article ID 9039754, 15 pages, 2016.
View at: Publisher Site | Google Scholar
S. PS, M. JA, B. L et al., “CYP-450 Epoxygenase Derived Epoxyeicosatrienoic Acid Contribute To Reversal of Heart Failure in Obesity-Induced Diabetic Cardiomyopathy via PGC-1α Activation,” Cardiovascular Pharmacology: Open Access, vol. 07, no. 01, 2018.
View at: Publisher Site | Google Scholar
M. Lehrke and M. A. Lazar, “The many faces of PPARγ,” Cell, vol. 123, no. 6, pp. 993–999, 2005.
View at: Publisher Site | Google Scholar
L. A. Stechschulte, P. J. Czernik, Z. C. Rotter et al., “PPARG Post-translational Modifications Regulate Bone Formation and Bone Resorption,” EBioMedicine, vol. 10, pp. 174–184, 2016.
View at: Publisher Site | Google Scholar
V. Kolli, L. A. Stechschulte, A. R. Dowling, S. Rahman, P. J. Czernik, and B. Lecka-Czernik, “Partial agonist, telmisartan, maintains PPARγ serine 112 phosphorylation, and does not affect osteoblast differentiation and bone mass,” PLoS ONE, vol. 9, no. 5, 2014.
View at: Google Scholar
Z. Drosatos-Tampakaki, K. Drosatos, Y. Siegelin et al., “Palmitic acid and DGAT1 deficiency enhance osteoclastogenesis, while oleic acid-induced triglyceride formation prevents it,” Journal of Bone and Mineral Research, vol. 29, no. 5, pp. 1183–1195, 2014.
View at: Publisher Site | Google Scholar
M. I. Queipo-Ortuño, X. Escoté, V. Ceperuelo-Mallafré et al., “FABP4 dynamics in obesity: discrepancies in adipose tissue and liver expression regarding circulating plasma levels,” PLoS ONE, vol. 7, no. 11, Article ID e48605, 2012.
View at: Publisher Site | Google Scholar
T. D. Hinds Jr., K. Sodhi, C. Meadows et al., “Increased HO-1 levels ameliorate fatty liver development through a reduction of heme and recruitment of FGF21,” Obesity, vol. 22, no. 3, pp. 705–712, 2014.
View at: Publisher Site | Google Scholar
D. E. Stec, K. John, C. J. Trabbic et al., “Bilirubin Binding to PPARalpha Inhibits Lipid Accumulation,” PLoS One, vol. 11, no. 4, Article ID e0153427.
View at: Google Scholar
T. D. Hinds, P. A. Hosick, S. Chen et al., “Mice with hyperbilirubinemia due to Gilbert's syndrome polymorphism are resistant to hepatic steatosis by decreased serine 73 phosphorylation of PPARalpha,” American Journal of Physiology-Endocrinology and Metabolism, vol. 312, no. 4, pp. E244–E252, 2017.
View at: Google Scholar

Copyright

Copyright © 2018 Marco Raffaele et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

3524

Downloads

1025

Citations