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Sample records for obesity induces upregulation

  1. Exercise protects against obesity induced semen abnormalities via downregulating stem cell factor, upregulating Ghrelin and normalizing oxidative stress.

    PubMed

    Alhashem, Fahaid; Alkhateeb, Mahmoud; Sakr, Hussein; Alshahrani, Mesfer; Alsunaidi, Mohammad; Elrefaey, Hesham; Alessa, Riyad; Sarhan, Mohammad; Eleawa, Samy M; Khalil, Mohammad A

    2014-01-01

    testes, diet induced obesity down regulates SCF expression, upregulates Ghrelin expression, and deteriorate oxidative stress levels, which are collectively detrimental to semen parameters. Exercise, and to a lesser extent Orlistat administration, protected effectively against this detrimental effect.

  2. Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

    SciTech Connect

    Liu, Wei-Xin; Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen; Gu, Shou-Zhi; Sang, Li-Xuan; Dai, Cong; Wang, Hai-Lan

    2015-04-10

    Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory

  3. p53-upregulated-modulator-of-apoptosis (PUMA) deficiency affects food intake but does not impact on body weight or glucose homeostasis in diet-induced obesity.

    PubMed Central

    Litwak, Sara A.; Loh, Kim; Stanley, William J.; Pappas, Evan G.; Wali, Jibran A.; Selck, Claudia; Strasser, Andreas; Thomas, Helen E.; Gurzov, Esteban N.

    2016-01-01

    BCL-2 proteins have been implicated in the control of glucose homeostasis and metabolism in different cell types. Thus, the aim of this study was to determine the role of the pro-apoptotic BH3-only protein, p53-upregulated-modulator-of-apoptosis (PUMA), in metabolic changes mediated by diet-induced obesity, using PUMA deficient mice. At 10 weeks of age, knockout and wild type mice either continued consuming a low fat chow diet (6% fat), or were fed with a high fat diet (23% fat) for 14–17 weeks. We measured body composition, glucose and insulin tolerance, insulin response in peripheral tissues, energy expenditure, oxygen consumption, and respiratory exchange ratio in vivo. All these parameters were indistinguishable between wild type and knockout mice on chow diet and were modified equally by diet-induced obesity. Interestingly, we observed decreased food intake and ambulatory capacity of PUMA knockout mice on high fat diet. This was associated with increased adipocyte size and fasted leptin concentration in the blood. Our findings suggest that although PUMA is dispensable for glucose homeostasis in lean and obese mice, it can affect leptin levels and food intake during obesity. PMID:27033313

  4. p53-upregulated-modulator-of-apoptosis (PUMA) deficiency affects food intake but does not impact on body weight or glucose homeostasis in diet-induced obesity.

    PubMed

    Litwak, Sara A; Loh, Kim; Stanley, William J; Pappas, Evan G; Wali, Jibran A; Selck, Claudia; Strasser, Andreas; Thomas, Helen E; Gurzov, Esteban N

    2016-04-01

    BCL-2 proteins have been implicated in the control of glucose homeostasis and metabolism in different cell types. Thus, the aim of this study was to determine the role of the pro-apoptotic BH3-only protein, p53-upregulated-modulator-of-apoptosis (PUMA), in metabolic changes mediated by diet-induced obesity, using PUMA deficient mice. At 10 weeks of age, knockout and wild type mice either continued consuming a low fat chow diet (6% fat), or were fed with a high fat diet (23% fat) for 14-17 weeks. We measured body composition, glucose and insulin tolerance, insulin response in peripheral tissues, energy expenditure, oxygen consumption, and respiratory exchange ratio in vivo. All these parameters were indistinguishable between wild type and knockout mice on chow diet and were modified equally by diet-induced obesity. Interestingly, we observed decreased food intake and ambulatory capacity of PUMA knockout mice on high fat diet. This was associated with increased adipocyte size and fasted leptin concentration in the blood. Our findings suggest that although PUMA is dispensable for glucose homeostasis in lean and obese mice, it can affect leptin levels and food intake during obesity.

  5. Adipogenic miR-27a in adipose tissue upregulates macrophage activation via inhibiting PPARγ of insulin resistance induced by high-fat diet-associated obesity.

    PubMed

    Yao, Fan; Yu, Yang; Feng, Linjing; Li, Junnan; Zhang, Meishuang; Lan, Xiaoxin; Yan, Xin; Liu, Yilun; Guan, Fengying; Zhang, Ming; Chen, Li

    2017-03-30

    Chronic low degree inflammation caused by macrophage activation is a crucial factor underlying insulin resistance induced by obesity. To illustrate the mechanism of regulating of macrophage activation in adipose tissue, the role of adipogenic miR-27a activating M1 macrophage polarization via blocking PPARγ was evaluated. Obese mice model and miR-27a overexpression or knockdown mice model were established and related biochemical index were examined. Raw264.7 and 3T3-L1 were cultured and co-cultured for mimicking the microenvironment of local inflammation. Macrophage infiltration was observed. MiR-27a and cytokines levels in serum and adipose tissue were measured. Macrophage polarization markers and protein expression in insulin or inflammatory signaling pathways were observed. Impaired glucose tolerance and insulin tolerance was observed in 4w, 8w and 12w of high fat diet and miR-27a overexpression mice. Concurrently, miR-27a was increased in serum in a time-dependent manner, along with M1 cytokines and M1 macrophages increasing in adipose tissue clearly. Insulin signaling pathway was blocked, and PPARγ was suppressed. However, NF-κB was activated. On the other hand, activated macrophages and hypertrophic adipocytes induced by miR-27a could increase the ratio of Raw264.7 migration, including improving cytokines generation, and blocking PPARγ expression markedly. The present studies are conducted to clarify that miR-27a has increased along with up-regulation in the process of proinflammatory cytokines generation, macrophage influx and M1 macrophage polarization in obesity. These indicate that miR-27a gives the novel target of intervention for inflammation and insulin resistance in obesity.

  6. Miglitol increases energy expenditure by upregulating uncoupling protein 1 of brown adipose tissue and reduces obesity in dietary-induced obese mice

    PubMed Central

    2014-01-01

    Background Miglitol is an oral anti-diabetic drug that acts by inhibiting carbohydrate absorption in the small intestine. Recent studies have shown that miglitol reduces obesity in humans and rodents. However, its mechanisms have remained unclear. The purpose of this study was to determine whether miglitol generates heat by activating uncoupling protein 1 (UCP1), an enzyme involved in thermogenesis, in brown adipose tissue (BAT) in mice. Methods Four-week-old male C57BL/6 J mice were fed a high-fat diet alone (HF) or a high fat diet plus miglitol (HFM). Oxygen consumption (VO2) was used to estimate metabolic rate. A thermal imaging camera was used to quantify heat generation from interscapular brown adipose tissue. We analyzed the protein and gene expressions of UCP1 and the expressions of four proteins related to β3-adrenergic signaling in the pathway activating UCP1 (protein kinase A (PKA), hormone-sensitive lipase (HSL), p38 α mitogen-activated protein kinase (p38αMAPK) and peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α)). Results At 8 weeks, body weight, epididymal and subcutaneous white adipose tissue and the HOMA-R value of the HFM mice were significantly less than those of the HF mice. Food intake was not different between the HF and HFM mice. VO2 and BAT temperature were significantly higher in the HFM mice. Miglitol significantly enhanced the gene and protein expressions of UCP1 and the expressions of proteins related to β3-adrenergic signaling. Conclusions Miglitol’s anti-obesity effect was attributed to increased energy expenditure by upregulating UCP1 in BAT (i.e., by thermogenesis) and to enhancement of β3-adrenergic signaling in BAT. PMID:24669882

  7. Renal angiotensin II type-2 receptors are upregulated and mediate the candesartan-induced natriuresis/diuresis in obese Zucker rats.

    PubMed

    Hakam, Amer C; Hussain, Tahir

    2005-02-01

    Recently, there has been a growing interest in studying the role of angiotensin II type-2 (AT(2)) receptor in renal/cardiovascular function in pathological conditions. The present study was designed to determine the functional role of the AT(2) receptors on natriuresis/diuresis and compare the level of the tubular AT(2) receptor expression in obese and lean Zucker rats (12 weeks old). Under anesthesia, candesartan (angiotensin II type 1 [AT(1)]-specific antagonist; 100 microg/kg bolus) produced natriuresis/diuresis to a greater degree in obese than in lean rats. The specific AT(2) antagonist PD123319 (50 microg/kg per minute) after candesartan administration abolished the natriuretic/diuretic effects of candesartan in obese rats but not in lean rats. Infusion of AT(2) receptor agonist, CGP-42112A (1 microg/kg per minute), produced greater increase in sodium and urine excretion over basal in obese than in lean rats. The presence of the AT(2) receptor expression in the brush-border and basolateral membranes was confirmed by Western blotting using specific antibody and antigen-blocking peptide. Densitometric analysis of the bands revealed approximately 1.5- to 2.0-fold increase in the AT(2) receptor proteins in both membranes of obese compared with lean rats. Our results suggest upregulation of the AT(2) receptors, which play a role in mediating the natriuretic/diuretic effects of AT(1) receptor blockers in obese Zucker rats. We speculate that AT(2) receptors, by promoting sodium excretion, may protect obese Zucker rats against blood pressure increase associated with sodium and water retention.

  8. Upregulation of orexin receptor in paraventricular nucleus promotes sympathetic outflow in obese Zucker rats.

    PubMed

    Zhou, Jing-Jing; Yuan, Fang; Zhang, Yi; Li, De-Pei

    2015-12-01

    Sympathetic vasomotor tone is elevated in obesity-related hypertension. Orexin importantly regulates energy metabolism and autonomic function. We hypothesized that alteration of orexin receptor in the paraventricular nucleus (PVN) of the hypothalamus leads to elevated sympathetic vasomotor tone in obesity. We used in vivo measurement of sympathetic vasomotor tone and microinjection into brain nucleus, whole-cell patch clamp recording in brain slices, and immunocytochemical staining in obese Zucker rats (OZRs) and lean Zucker rats (LZRs). Microinjection of orexin 1 receptor (OX1R) antagonist SB334867 into the PVN reduced basal arterial blood pressure (ABP) and renal sympathetic nerve activity (RSNA) in anesthetized OZRs but not in LZRs. Microinjection of orexin A into the PVN produced greater increases in ABP and RSNA in OZRs than in LZRs. Western blot analysis revealed that OX1R expression levels in the PVN were significantly increased in OZRs compared with LZRs. OX1R immunoreactivity was positive in retrogradely labeled PVN-spinal neurons. The basal firing rate of labeled PVN-spinal neurons was higher in OZRs than in LZRs. SB334867 decreased the basal firing activity of PVN-spinal neurons in OZRs but had no effect in LZRs. Orexin A induced a greater increase in the firing rate of PVN-spinal neurons in OZRs than in LZRs. In addition, orexin A induced larger currents in PVN-spinal neurons in OZRs than in LZRs. These data suggest that upregulation of OX1R in the PVN promotes hyperactivity of PVN presympathetic neurons and elevated sympathetic outflow in obesity.

  9. Maternal obesity is associated with ovarian inflammation and up-regulation of early growth response factor 1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity impairs reproductive functions through multiple mechanisms, possibly through disruption of ovarian function. We hypothesized that increased adiposity will lead to a pro-inflammatory gene signature and up-regulation of Egr-1 protein in ovaries from obese (OB, n=7) compared to lean (LN, n=10) ...

  10. T-cell accumulation and regulated on activation, normal T cell expressed and secreted upregulation in adipose tissue in obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is associated with chronic inflammation, which includes increased macrophage accumulation in adipose tissue (AT) and upregulation of chemokines and cytokines. T cells also play important roles in chronic inflammatory diseases such as atherosclerosis but have not been well studied in obesity....

  11. Transcription upregulation via force-induced direct stretching of chromatin

    NASA Astrophysics Data System (ADS)

    Tajik, Arash; Zhang, Yuejin; Wei, Fuxiang; Sun, Jian; Jia, Qiong; Zhou, Wenwen; Singh, Rishi; Khanna, Nimish; Belmont, Andrew S.; Wang, Ning

    2016-12-01

    Mechanical forces play critical roles in the function of living cells. However, the underlying mechanisms of how forces influence nuclear events remain elusive. Here, we show that chromatin deformation as well as force-induced transcription of a green fluorescent protein (GFP)-tagged bacterial-chromosome dihydrofolate reductase (DHFR) transgene can be visualized in a living cell by using three-dimensional magnetic twisting cytometry to apply local stresses on the cell surface via an Arg-Gly-Asp-coated magnetic bead. Chromatin stretching depended on loading direction. DHFR transcription upregulation was sensitive to load direction and proportional to the magnitude of chromatin stretching. Disrupting filamentous actin or inhibiting actomyosin contraction abrogated or attenuated force-induced DHFR transcription, whereas activating endogenous contraction upregulated force-induced DHFR transcription. Our findings suggest that local stresses applied to integrins propagate from the tensed actin cytoskeleton to the LINC complex and then through lamina-chromatin interactions to directly stretch chromatin and upregulate transcription.

  12. The "Big Bang" in obese fat: Events initiating obesity-induced adipose tissue inflammation.

    PubMed

    Wensveen, Felix M; Valentić, Sonja; Šestan, Marko; Turk Wensveen, Tamara; Polić, Bojan

    2015-09-01

    Obesity is associated with the accumulation of pro-inflammatory cells in visceral adipose tissue (VAT), which is an important underlying cause of insulin resistance and progression to diabetes mellitus type 2 (DM2). Although the role of pro-inflammatory cytokines in disease development is established, the initiating events leading to immune cell activation remain elusive. Lean adipose tissue is predominantly populated with regulatory cells, such as eosinophils and type 2 innate lymphocytes. These cells maintain tissue homeostasis through the excretion of type 2 cytokines, such as IL-4, IL-5, and IL-13, which keep adipose tissue macrophages (ATMs) in an anti-inflammatory, M2-like state. Diet-induced obesity is associated with the loss of tissue homeostasis and development of type 1 inflammatory responses in VAT, characterized by IFN-γ. A key event is a shift of ATMs toward an M1 phenotype. Recent studies show that obesity-induced adipocyte hypertrophy results in upregulated surface expression of stress markers. Adipose stress is detected by local sentinels, such as NK cells and CD8(+) T cells, which produce IFN-γ, driving M1 ATM polarization. A rapid accumulation of pro-inflammatory cells in VAT follows, leading to inflammation. In this review, we provide an overview of events leading to adipose tissue inflammation, with a special focus on adipose homeostasis and the obesity-induced loss of homeostasis which marks the initiation of VAT inflammation.

  13. Upregulation of Gingival Tissue miR-200b in Obese Periodontitis Subjects

    PubMed Central

    Kalea, A.Z.; Hoteit, R.; Suvan, J.; Lovering, R.C.; Palmen, J.; Cooper, J.A.; Khodiyar, V.K.; Harrington, Z.; Humphries, S.E.; D’Aiuto, F.

    2015-01-01

    Increased local immune and inflammatory responses in obese individuals with periodontitis may explain the aggressive clinical presentation and altered treatment response when compared to that of normal weight subjects. Our goal was to identify any differences in microRNA (miRNA) expression profiles of gingival tissue in periodontitis when obesity is present, which may suggest novel molecular pathways that this miRNA network may affect. Total RNA was extracted from gingival tissue biopsies collected from normal weight and obese individuals with periodontitis; miRNA expression profiling was performed with Affymetrix GeneChip miRNA 3.0 arrays; and results were validated with quantitative reverse transcription polymerase chain reaction (qRT-PCR). In silico identification of previously confirmed miRNA gene targets was conducted through miRTarBase and miRWalk databases, and pathway enrichment analysis identified enriched miRNA gene sets. Expression of selected genes in the same biopsy samples was tested with qRT-PCR. The gingival tissue miRNA profile of obese patients, compared to that of normal weight patients, showed 13 upregulated and 22 downregulated miRNAs, among which miR-200b was validated by qRT-PCR to be significantly increased in obesity. Functional analysis of 51 experimentally validated miR-200b gene targets identified enrichment of genes involved in cell motility, differentiation, DNA binding, response to stimulus, and vasculature development pathways not previously identified in the obesity-specific disease profile. Furthermore, the expression of the miR-200b gene targets ZEB1/2, GATA2, and KDR was confirmed by qRT-PCR as being lower in obese patients with periodontitis versus normal weight patients, suggesting a role of miR-200b in regulation of a set of gene targets and biological pathways relevant to wound healing and angiogenesis. Functional studies to explore the role of miR-200b in the above processes may offer new insights on putative therapeutic

  14. Transcription upregulation via force-induced direct stretching of chromatin

    PubMed Central

    Tajik, Arash; Zhang, Yuejin; Wei, Fuxiang; Sun, Jian; Jia, Qiong; Zhou, Wenwen; Singh, Rishi; Khanna, Nimish; Belmont, Andrew S.; Wang, Ning

    2016-01-01

    Mechanical forces play critical roles in the function of living cells. However, the underlying mechanisms of how forces influence nuclear events remain elusive. Here, we show that chromatin deformation as well as force-induced transcription of a green-fluorescent-protein (GFP) tagged bacterial-chromosome dihydrofolate reductase (DHFR) transgene can be visualized in a living cell by using three-dimensional magnetic twisting cytometry to apply local stresses on the cell surface via an Arg-Gly-Asp-coated magnetic bead. Chromatin stretching depended on loading direction. DHFR transcription upregulation was sensitive to load direction and proportional to the magnitude of chromatin stretching. Disrupting filamentous actin or inhibiting actomyosin contraction abrogated or attenuated force-induced DHFR transcription, whereas activating endogenous contraction upregulated force-induced DHFR transcription. Our findings suggest that local stresses applied to integrins propagate from the tensed actin cytoskeleton to the LINC complex and then through lamina-chromatin interactions to directly stretch chromatin and upregulate transcription. PMID:27548707

  15. Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation

    SciTech Connect

    Yeom, Chul-gon; Kim, Dong-il; Park, Min-jung; Choi, Joo-hee; Jeong, Jieun; Wi, Anjin; Park, Whoashig; Han, Ho-jae; Park, Soo-hyun

    2015-06-05

    Previously, we reported that CARM1 undergoes ubiquitination-dependent degradation in renal podocytes. It was also reported that CARM1 is necessary for fasting-induced hepatic gluconeogenesis. Based on these reports, we hypothesized that treatment with insulin, a hormone typically present under the ‘fed’ condition, would inhibit gluconeogenesis via CARM1 degradation. HepG2 cells, AML-12 cells, and rat primary hepatocytes were treated with insulin to confirm CARM1 downregulation. Surprisingly, insulin treatment increased CARM1 expression in all cell types examined. Furthermore, treatment with insulin increased histone 3 methylation at arginine 17 and 26 in HepG2 cells. To elucidate the role of insulin-induced CARM1 upregulation, the HA-CARM1 plasmid was transfected into HepG2 cells. CARM1 overexpression did not increase the expression of lipogenic proteins generally increased by insulin signaling. Moreover, CARM1 knockdown did not influence insulin sensitivity. Insulin is known to facilitate hepatic proliferation. Like insulin, CARM1 overexpression increased CDK2 and CDK4 expression. In addition, CARM1 knockdown reduced the number of insulin-induced G2/M phase cells. Moreover, GFP-CARM1 overexpression increased the number of G2/M phase cells. Based on these results, we concluded that insulin-induced CARM1 upregulation facilitates hepatocyte proliferation. These observations indicate that CARM1 plays an important role in liver pathophysiology. - Highlights: • Insulin treatment increases CARM1 expression in hepatocytes. • CARM1 overexpression does not increase the expression of lipogenic proteins. • CARM1 knockdown does not influence insulin sensitivity. • Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation.

  16. Upregulated copper transporters in hypoxia-induced pulmonary hypertension.

    PubMed

    Zimnicka, Adriana M; Tang, Haiyang; Guo, Qiang; Kuhr, Frank K; Oh, Myung-Jin; Wan, Jun; Chen, Jiwang; Smith, Kimberly A; Fraidenburg, Dustin R; Choudhury, Moumita S R; Levitan, Irena; Machado, Roberto F; Kaplan, Jack H; Yuan, Jason X-J

    2014-01-01

    Pulmonary vascular remodeling and increased arterial wall stiffness are two major causes for the elevated pulmonary vascular resistance and pulmonary arterial pressure in patients and animals with pulmonary hypertension. Cellular copper (Cu) plays an important role in angiogenesis and extracellular matrix remodeling; increased Cu in vascular smooth muscle cells has been demonstrated to be associated with atherosclerosis and hypertension in animal experiments. In this study, we show that the Cu-uptake transporter 1, CTR1, and the Cu-efflux pump, ATP7A, were both upregulated in the lung tissues and pulmonary arteries of mice with hypoxia-induced pulmonary hypertension. Hypoxia also significantly increased expression and activity of lysyl oxidase (LOX), a Cu-dependent enzyme that causes crosslinks of collagen and elastin in the extracellular matrix. In vitro experiments show that exposure to hypoxia or treatment with cobalt (CoCl2) also increased protein expression of CTR1, ATP7A, and LOX in pulmonary arterial smooth muscle cells (PASMC). In PASMC exposed to hypoxia or treated with CoCl2, we also confirmed that the Cu transport is increased using 64Cu uptake assays. Furthermore, hypoxia increased both cell migration and proliferation in a Cu-dependent manner. Downregulation of hypoxia-inducible factor 1α (HIF-1α) with siRNA significantly attenuated hypoxia-mediated upregulation of CTR1 mRNA. In summary, the data from this study indicate that increased Cu transportation due to upregulated CTR1 and ATP7A in pulmonary arteries and PASMC contributes to the development of hypoxia-induced pulmonary hypertension. The increased Cu uptake and elevated ATP7A also facilitate the increase in LOX activity and thus the increase in crosslink of extracellular matrix, and eventually leading to the increase in pulmonary arterial stiffness.

  17. PDGF upregulates CLEC-2 to induce T regulatory cells.

    PubMed

    Agrawal, Sudhanshu; Ganguly, Sreerupa; Hajian, Pega; Cao, Jia-Ning; Agrawal, Anshu

    2015-10-06

    The effect of platelet derived growth factor (PDGF) on immune cells is not elucidated. Here, we demonstrate PDGF inhibited the maturation of human DCs and induced IL-10 secretion. Culture of PDGF-DCs with T cells induced the polarization of T cells towards FoxP3 expressing T regulatory cells that secreted IL-10. Gene expression studies revealed that PDGF induced the expression of C-type lectin like receptor member 2, (CLEC-2) receptor on DCs. Furthermore, DCs transfected with CLEC-2 induced T regulatory cells in DC-T cell co-culture. CLEC-2 is naturally expressed on platelets. Therefore, to confirm whether CLEC-2 is responsible for inducing the T regulatory cells, T cells were cultured with either CLEC-2 expressing platelets or soluble CLEC-2. Both conditions resulted in the induction of regulatory T cells. The generation of T regulatory cells was probably due to the binding of CLEC-2 with its ligand podoplanin on T cells, since crosslinking of podoplanin on the T cells also resulted in the induction of T regulatory cells. These data demonstrate that PDGF upregulates the expression of CLEC-2 on cells to induce T regulatory cells.

  18. Up-regulated expression of microRNA-143 in association with obesity in adipose tissue of mice fed high-fat diet.

    PubMed

    Takanabe, Rieko; Ono, Koh; Abe, Yukiko; Takaya, Tomohide; Horie, Takahiro; Wada, Hiromichi; Kita, Toru; Satoh, Noriko; Shimatsu, Akira; Hasegawa, Koji

    2008-11-28

    MicroRNAs (miRNAs) are short non-coding RNA that post-transcriptionally regulates gene expression. miR-143 has been proposed to play a role in the differentiation of adipocytes in culture. However, the mechanism regulating the expression of miR-143 in adult adipose tissue during the development of obesity in vivo is unknown. Here in, we showed that the expression of miR-143 in the mesenteric fat was up-regulated in mice fed a high-fat diet. Increased miR-143 expression was associated with an elevated body weight and mesenteric fat weight. Furthermore, miR-143 levels were closely correlated with expression levels of adipocyte differentiation markers such as PPARgamma and aP2 as well as plasma levels of leptin, one of the important adipocytokines involved in insulin resistance. These findings provide the first evidence for the up-regulated expression of miR-143 in the mesenteric fat of high-fat diet-induced obese mice, which might contribute to the regulated expression of adipocyte genes involved in the pathophysiology of obesity.

  19. Visceral Adipose MicroRNA 223 Is Upregulated in Human and Murine Obesity and Modulates the Inflammatory Phenotype of Macrophages

    PubMed Central

    Syed, Rafay; Duggineni, Dheeraj; Rutsky, Jessica; Rengasamy, Palanivel; Zhang, Jie; Huang, Kun; Needleman, Bradley; Mikami, Dean; Perry, Kyle; Hazey, Jeffrey; Rajagopalan, Sanjay

    2016-01-01

    Obesity in humans and mice is typified by an activated macrophage phenotype in the visceral adipose tissue (VAT) leading to increased macrophage-mediated inflammation. microRNAs (miRNAs) play an important role in regulating inflammatory pathways in macrophages, and in this study we compared miRNA expression in the VAT of insulin resistant morbidly obese humans to a non-obese cohort with normal glucose tolerance. miR-223-3p was found to be significantly upregulated in the whole omental tissue RNA of 12 human subjects, as were 8 additional miRNAs. We then confirmed that miR-223 upregulation was specific to the stromal vascular cells of human VAT, and found that miR-223 levels were unchanged in adipocytes and circulating monocytes of the non-obese and obese. miR-223 ablation increased basal / unstimulated TLR4 and STAT3 expression and LPS-stimulated TLR4, STAT3, and NOS2 expression in primary macrophages. Conversely, miR-223 mimics decreased TLR4 expression in primary macrophage, at the same time it negatively regulated FBXW7 expression, a well described suppressor of Toll-like receptor 4 (TLR4) signaling. We concluded that the abundance of miR-223 in macrophages significantly modulates macrophage phenotype / activation state and response to stimuli via effects on the TLR4/FBXW7 axis. PMID:27812198

  20. Ibuprofen enhances TRAIL-induced apoptosis through DR5 upregulation.

    PubMed

    Todo, Momoko; Horinaka, Mano; Tomosugi, Mitsuhiro; Tanaka, Ryoichi; Ikawa, Haruna; Sowa, Yoshihiro; Ishikawa, Hideki; Fujiwara, Hitoshi; Otsuji, Eigo; Sakai, Toshiyuki

    2013-11-01

    Numerous human chemoprevention studies have demonstrated that non-steroidal anti-inflammatory drugs (NSAIDs) possess chemopreventive effects against a variety of malignant tumors. However, there have been many clinical studies on aspirin, but not ibuprofen, even though ibuprofen is one of the most clinically and safely used NSAIDs showing potent anti-inflammatory effects. Moreover, we reported that many chemopreventive agents enhance the apoptosis-inducing effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), which is known to be crucial for cancer prevention. We, therefore, investigated whether ibuprofen enhances the cytocidal effect of TRAIL and found that ibuprofen markedly stimulated the apoptosis-inducing efficacy of TRAIL against human colon cancer HCT116 cells. As detected by western blot analysis and real-time RT-PCR, ibuprofen upregulated the expression of death receptor 5 (DR5), a TRAIL receptor. TRAIL-induced apoptosis enhanced by ibuprofen was effectively decreased by a caspase inhibitor and dominant-negative DR5. Noteworthy, co-treatment of ibuprofen with TRAIL did not enhance apoptosis in normal peripheral blood mononuclear cells (PBMCs). These results demonstrated that ibuprofen and TRAIL synergistically induced apoptosis in human colon cancer HCT116 cells but not in normal PBMCs, raising the possibility that ibuprofen may be promising as a safe chemopreventive agent against colon cancer.

  1. Ginsenoside Rb1 ameliorates liver fat accumulation by upregulating perilipin expression in adipose tissue of db/db obese mice

    PubMed Central

    Yu, Xizhong; Ye, Lifang; Zhang, Hao; Zhao, Juan; Wang, Guoqiang; Guo, Chao; Shang, Wenbin

    2014-01-01

    Background Ginsenoside Rb1 (G-Rb1), the major active constituent of ginseng, improves insulin sensitivity and exerts antidiabetic effects. We tested whether the insulin-sensitizing and antidiabetic effects of G-Rb1 results from a reduction in ectopic fat accumulation, mediated by inhibition of lipolysis in adipocytes. Methods Obese and diabetic db/db mice were treated with daily doses of 20 mg/kg G-Rb1 for 14 days. Hepatic fat accumulation was evaluated by measuring liver weight and triglyceride content. Levels of blood glucose and serum insulin were used to evaluate insulin sensitivity in db/db mice. Lipolysis in adipocytes was evaluated by measuring plasma-free fatty acids and glycerol release from 3T3-L1 adipocytes treated with G-Rb1. The expression of relevant genes was analyzed by western blotting, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay kit. Results G-Rb1 increased insulin sensitivity and alleviated hepatic fat accumulation in obese diabetic db/db mice, and these effects were accompanied by reduced liver weight and hepatic triglyceride content. Furthermore, G-Rb1 lowered the levels of free fatty acids in obese mice, which may contribute to a decline in hepatic lipid accumulation. Corresponding to these results, G-Rb1 significantly suppressed lipolysis in 3T3-L1 adipocytes and upregulated the perilipin expression in both 3T3-L1 adipocytes and mouse epididymal fat pads. Moreover, G-Rb1 increased the level of adiponectin and reduced that of tumor necrosis factor-α in obese mice, and these effects were confirmed in 3T3-L1 adipocytes. Conclusion G-Rb1 may improve insulin sensitivity in obese and diabetic db/db mice by reducing hepatic fat accumulation and suppressing adipocyte lipolysis; these effects may be mediated via the upregulation of perilipin expression in adipocytes. PMID:26199550

  2. Free Fatty Acids Induce Autophagy and LOX-1 Upregulation in Cultured Aortic Vascular Smooth Muscle Cells.

    PubMed

    Cheng, Cheng-I; Lee, Yueh-Hong; Chen, Po-Han; Lin, Yu-Chun; Chou, Ming-Huei; Kao, Ying-Hsien

    2016-11-05

    Elevation of free fatty acids (FFAs) is known to affect microvascular function and contribute to obesity-associated insulin resistance, hypertension, and microangiopathy. Proliferative and synthetic vascular smooth muscle cells (VSMCs) increase intimal thickness and destabilize atheromatous plaques. This study aimed to investigate whether saturated palmitic acid (PA) and monounsaturated oleic acid (OA) modulate autophagy activity, cell proliferation, and vascular tissue remodeling in an aortic VSMC cell line. Exposure to PA and OA suppressed growth of VSMCs without apoptotic induction, but enhanced autophagy flux with elevation of Beclin-1, Atg5, and LC3I/II. Cotreatment with autophagy inhibitors potentiated the FFA-suppressed VSMC growth and showed differential actions of PA and OA in autophagy flux retardation. Both FFAs upregulated lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) but only OA increased LDL uptake by VSMCs. Mechanistically, FFAs induced hyperphosphorylation of Akt, ERK1/2, JNK1/2, and p38 MAPK. All pathways, except OA-activated PI3K/Akt cascade, were involved in the LOX-1 upregulation, whereas blockade of PI3K/Akt and MEK/ERK cascades ameliorated the FFA-induced growth suppression on VSMCs. Moreover, both FFAs exhibited tissue remodeling effect through increasing MMP-2 and MMP-9 expression and their gelatinolytic activities, whereas high-dose OA significantly suppressed collagen type I expression. Conversely, siRNA-mediated LOX-1 knockdown significantly attenuated the OA-induced tissue remodeling effects in VSMCs. In conclusion, OA and PA enhance autophagy flux, suppress aortic VSMC proliferation, and exhibit vascular remodeling effect, thereby leading to the loss of VSMCs and interstitial ECM in vascular walls and eventually the instability of atheromatous plaques. J. Cell. Biochem. 9999: 1-13, 2016. © 2016 Wiley Periodicals, Inc.

  3. A Rat Model to Study the Effects of Diet-Induced Obesity on Radiation-Induced Mammary Carcinogenesis.

    PubMed

    Imaoka, Tatsuhiko; Nishimura, Mayumi; Daino, Kazuhiro; Morioka, Takamitsu; Nishimura, Yukiko; Uemura, Hiroji; Akimoto, Kenta; Furukawa, Yuki; Fukushi, Masahiro; Wakabayashi, Keiji; Mutoh, Michihiro; Shimada, Yoshiya

    2016-05-01

    A detailed understanding of the relationship between radiation-induced breast cancer and obesity is needed for appropriate risk management and to prevent the development of a secondary cancer in patients who have been treated with radiation. Our goal was to develop an animal model to study the relationship by combining two existing Sprague-Dawley rat models of radiation-induced mammary carcinogenesis and diet-induced obesity. Female rats were fed a high-fat diet for 4 weeks and categorized as obesity prone or obesity resistant based on their body weight at 7 weeks of age, at which time the rats were irradiated with 4 Gy. Control rats were fed a standard diet and irradiated at the same time and in the same manner. All rats were maintained on their initial diets and assessed for palpable mammary cancers once a week for the next 30 weeks. The obesity-prone rats were heavier than those in the other groups. The obesity-prone rats were also younger than the other animals at the first detection of mammary carcinomas and their carcinoma weights were greater. A tendency toward higher insulin and leptin blood levels were observed in the obesity-prone rats compared to the other two groups. Blood angiotensin II levels were elevated in the obesity-prone and obesity-resistant rats. Genes related to translation and oxidative phosphorylation were upregulated in the carcinomas of obesity-prone rats. Expression profiles from human breast cancers were used to validate this animal model. As angiotensin is potentially an important factor in obesity-related morbidities and breast cancer, a second set of rats was fed in a similar manner, irradiated and then treated with an angiotensin-receptor blocker, losartan and candesartan. Neither blocker altered mammary carcinogenesis; analyses of losartan-treated animals indicated that expression of renin in the renal cortex and of Agtr1a (angiotensin II receptor, type 1) in cancer tissue was significantly upregulated, suggesting the presence of

  4. FGF-2 induces neuronal death through upregulation of system xc-.

    PubMed

    Liu, Xiaoqian; Albano, Rebecca; Lobner, Doug

    2014-02-14

    The cystine/glutamate antiporter (system xc-) transports cystine into cell in exchange for glutamate. Fibroblast growth factor-2 (FGF-2) upregulates system xc- selectively on astrocytes, which leads to increased cystine uptake, the substrate for glutathione production, and increased glutamate release. While increased intracellular glutathione can limit oxidative stress, the increased glutamate release can potentially lead to excitotoxicity to neurons. To test this hypothesis, mixed neuronal and glial cortical cultures were treated with FGF-2. Treatment with FGF-2 for 48 h caused a significant neuronal death in these cultures. Cell death was not observed in neuronal-enriched cultures, or astrocyte-enriched cultures, suggesting the toxicity was the result of neuron-glia interaction. Blocking system xc- eliminated the neuronal death as did the AMPA/kainate receptor antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione (NBQX), but not the NMDA receptor antagonist memantine. When cultures were exposed directly to glutamate, both NBQX and memantine blocked the neuronal toxicity. The mechanism of this altered profile of glutamate receptor mediated toxicity by FGF-2 is unclear. The selective calcium permeable AMPA receptor antagonist 1-naphthyl acetyl spermine (NASPM) failed to offer protection. The most likely explanation for the results is that 48 h FGF-2 treatment induces AMPA/kainate receptor toxicity through increased system xc- function resulting in increased release of glutamate. At the same time, FGF-2 alters the sensitivity of the neurons to glutamate toxicity in a manner that promotes selective AMPA/kainate receptor mediated toxicity.

  5. Calcium deficiency cannot induce obesity in rats.

    PubMed

    Paradis, S; Cabanac, M

    2005-06-30

    If intake of a required nutrient--here calcium--affects body weight, the effect must be mediated by a change in the body weight set-point. Thus, the controversial 'anti-obesity' influence of high calcium intake should decrease the body weight set-point. Diets differing in calcium content were assigned to three groups of rats. The effects of the diets on body weight, BMI, fat content, plasma calcium, body weight set-point, food intake, and preference for various calcium solutions were measured after 6 weeks of calcium deprivation or supplementation, and again after a further 6 weeks of recovery on a regular diet. After 6 weeks, the low-calcium diet had induced calcium deficiency but had failed to raise the body weight set-point. Nor had it produced obesity or fat accumulation. After 6 weeks of recovery, body weight and fat content were no higher in calcium-deprived rats than in the control or supplemented rats. In this experiment, low-calcium intake failed to cause obesity and did not raise the body weight set-point. The results indicate that calcium intake probably does not affect body weight.

  6. miR-155 Deletion in Female Mice Prevents Diet-Induced Obesity

    PubMed Central

    Gaudet, Andrew D.; Fonken, Laura K.; Gushchina, Liubov V.; Aubrecht, Taryn G.; Maurya, Santosh K.; Periasamy, Muthu; Nelson, Randy J.; Popovich, Phillip G.

    2016-01-01

    Obesity is a growing epidemic in developed countries. Obese individuals are susceptible to comorbidities, including cardiovascular disease and metabolic disorder. Increasing the ability of adipose tissue to expend excess energy could improve protection from obesity. One promising target is microRNA (miR)-155-5p. We demonstrate that deletion of miR-155 (-5p and -3p) in female mice prevents diet-induced obesity. Body weight gain did not differ between wild-type (WT) and miR-155 knockout (KO) mice fed control diet (CD); however, miR-155 KO mice fed high-fat diet (HFD) gained 56% less body weight and 74% less gonadal white adipose tissue (WAT) than WT mice. Enhanced WAT thermogenic potential, brown adipose tissue differentiation, and/or insulin sensitivity might underlie this obesity resistance. Indeed, miR-155 KO mice on HFD had 21% higher heat release than WT HFD mice. Compared to WT adipocytes, miR-155 KO adipocytes upregulated brown (Ucp1, Cidea, Pparg) and white (Fabp4, Pnpla2, AdipoQ, Fasn) adipogenic genes, and glucose metabolism genes (Glut4, Irs1). miR-155 deletion abrogated HFD-induced adipocyte hypertrophy and WAT inflammation. Therefore, miR-155 deletion increases adipogenic, insulin sensitivity, and energy uncoupling machinery, while limiting inflammation in WAT, which together could restrict HFD-induced fat accumulation. Our results identify miR-155 as a novel candidate target for improving obesity resistance. PMID:26953132

  7. The role of osteopontin in D-galactosamine-induced liver injury in genetically obese mice

    SciTech Connect

    Kwon, Hyo-Jung; Won, Young-Suk; Yoon, Won-Kee; Nam, Ki-Hoan; Kim, Dae-Yong; Kim, Hyoung-Chin

    2010-02-01

    Various epidemiological studies have shown that obesity increases the risk of liver disease, but the precise mechanisms through which this occurs are poorly understood. In the present study, we hypothesized that osteopontin (OPN), an extracellular matrix and proinflammatory cytokine, has an important role in making obese mice more susceptible to inflammatory liver injury. After exposure of genetically obese ob/ob and db/db mice to a single dose of D-galactosamine (GalN), the plasma liver enzyme levels, histology and expression levels of cytokines and OPN were evaluated. The ob/ob and db/db mice, which were more sensitive to GalN-induced inflammatory liver injury compared with wild-type mice, had significantly higher plasma and hepatic OPN expression levels. Increased OPN expression was mainly found in hepatocytes and inflammatory cells and was correlated with markedly up-regulated interleukin (IL)-12 and IL-18 levels. Furthermore, pretreatment with a neutralizing OPN (nOPN) antibody attenuated the GalN-induced inflammatory liver injury in ob/ob and db/db mice, which was accompanied by significantly reduced macrophages recruitment and IL-12 and IL-18 productions. Taken together, these results suggest that up-regulated OPN expression is a contributing factor to increased susceptibility of genetically obese mice to GalN-induced liver injury by promoting inflammation and modulating immune response.

  8. Nutraceutical up-regulation of serotonin paradoxically induces compulsive behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The role of diet in either the etiology or treatment of complex mental disorder is highly controversial in psychiatry. However, physiological mechanisms by which diet can influence brain chemistry – particularly that of serotonin – are well established. Here we show that dietary up-regulation of br...

  9. New developments in the pathogenesis of obesity-induced hypertension.

    PubMed

    Kotsis, Vasilios; Nilsson, Peter; Grassi, Guido; Mancia, Giuseppe; Redon, Josep; Luft, Frank; Schmieder, Roland; Engeli, Stefan; Stabouli, Stella; Antza, Christina; Pall, Denes; Schlaich, Markus; Jordan, Jens

    2015-08-01

    Obesity is a disorder that develops from the interaction between genotype and environment involving social, behavioral, cultural, and physiological factors. Obesity increases the risk for type 2 diabetes mellitus, hypertension, cardiovascular disease, cancer, musculoskeletal disorders, chronic kidney and pulmonary disease. Although obesity is clearly associated with an increased prevalence of hypertension, many obese individuals may not develop hypertension. Protecting factors may exist and it is important to understand why obesity is not always related to hypertension. The aim of this review is to highlight the knowledge gap for the association between obesity, hypertension, and potential genetic and racial differences or environmental factors that may protect obese patients against the development of hypertension and other co-morbidities. Specific mutations in the leptin and the melaninocortin receptor genes in animal models of obesity without hypertension, the actions of α-melanocyte stimulating hormone, and SNS activity in obesity-related hypertension may promote recognition of protective and promoting factors for hypertension in obesity. Furthermore, gene-environment interactions may have the potential to modify gene expression and epigenetic mechanisms could also contribute to the heritability of obesity-induced hypertension. Finally, differences in nutrition, gut microbiota, exposure to sun light and exercise may play an important role in the presence or absence of hypertension in obesity.

  10. Upregulation of ERK1/2-eNOS via AT2 Receptors Decreases the Contractile Response to Angiotensin II in Resistance Mesenteric Arteries from Obese Rats

    PubMed Central

    Hagihara, Graziela N.; Lobato, Nubia S.; Filgueira, Fernando P.; Akamine, Eliana H.; Aragão, Danielle S.; Casarini, Dulce E.; Carvalho, Maria Helena C.; Fortes, Zuleica B.

    2014-01-01

    It has been clearly established that mitogen-activated protein kinases (MAPKS) are important mediators of angiotensin II (Ang II) signaling via AT1 receptors in the vasculature. However, evidence for a role of these kinases in changes of Ang II-induced vasoconstriction in obesity is still lacking. Here we sought to determine whether vascular MAPKs are differentially activated by Ang II in obese animals. The role of AT2 receptors was also evaluated. Male monosodium glutamate-induced obese (obese) and non-obese Wistar rats (control) were used. The circulating concentrations of Ang I and Ang II, determined by HPLC, were increased in obese rats. Ang II-induced isometric contraction was decreased in endothelium-intact resistance mesenteric arteries from obese compared with control rats and exhibited a retarded AT1 receptor antagonist response. Blocking of AT2 receptors and inhibition of either endothelial nitric oxide synthase (eNOS) or extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) restored Ang II-induced contraction in obese rats. Western blot analysis revealed increased protein expression of AT2 receptors in arteries from obese rats. Basal and Ang II-induced ERK1/2 phosphorylation was also increased in obese rats. Blockade of either AT1 or AT2 receptors corrected the increased ERK1/2 phosphorylation in arteries from obese rats to levels observed in control preparations. Phosphorylation of eNOS was increased in obese rats. Incubation with the ERK1/2 inhibitor before Ang II stimulation did not affect eNOS phosphorylation in control rats; however, it corrected the increased phosphorylation of eNOS in obese rats. These results clearly demonstrate that enhanced AT2 receptor and ERK1/2-induced, NO-mediated vasodilation reduces Ang II-induced contraction in an endothelium-dependent manner in obese rats. PMID:25170617

  11. Targeting inflammation-induced obesity and metabolic diseases by curcumin and other nutraceuticals.

    PubMed

    Aggarwal, Bharat B

    2010-08-21

    Extensive research within the past two decades has revealed that obesity, a major risk factor for type 2 diabetes, atherosclerosis, cancer, and other chronic diseases, is a proinflammatory disease. Several spices have been shown to exhibit activity against obesity through antioxidant and anti-inflammatory mechanisms. Among them, curcumin, a yellow pigment derived from the spice turmeric (an essential component of curry powder), has been investigated most extensively as a treatment for obesity and obesity-related metabolic diseases. Curcumin directly interacts with adipocytes, pancreatic cells, hepatic stellate cells, macrophages, and muscle cells. There, it suppresses the proinflammatory transcription factors nuclear factor-kappa B, signal transducer and activators of transcription-3, and Wnt/beta-catenin, and it activates peroxisome proliferator-activated receptor-gamma and Nrf2 cell-signaling pathways, thus leading to the downregulation of adipokines, including tumor necrosis factor, interleukin-6, resistin, leptin, and monocyte chemotactic protein-1, and the upregulation of adiponectin and other gene products. These curcumin-induced alterations reverse insulin resistance, hyperglycemia, hyperlipidemia, and other symptoms linked to obesity. Other structurally homologous nutraceuticals, derived from red chili, cinnamon, cloves, black pepper, and ginger, also exhibit effects against obesity and insulin resistance.

  12. Targeting Inflammation-Induced Obesity and Metabolic Diseases by Curcumin and Other Nutraceuticals

    PubMed Central

    Aggarwal, Bharat B.

    2011-01-01

    Extensive research within the past two decades has revealed that obesity, a major risk factor for type 2 diabetes, atherosclerosis, cancer, and other chronic diseases, is a proinflammatory disease. Several spices have been shown to exhibit activity against obesity through antioxidant and anti-inflammatory mechanisms. Among them, curcumin, a yellow pigment derived from the spice turmeric (an essential component of curry powder), has been investigated most extensively as a treatment for obesity and obesity-related metabolic diseases. Curcumin directly interacts with adipocytes, pancreatic cells, hepatic stellate cells, macrophages, and muscle cells. There, it suppresses the proinflammatory transcription factors nuclear factor-kappa B, signal transducer and activators of transcription-3, and Wnt/β-catenin, and it activates peroxisome proliferator-activated receptor-γ and Nrf2 cell-signaling pathways, thus leading to the downregulation of adipokines, including tumor necrosis factor, interleukin-6, resistin, leptin, and monocyte chemotactic protein-1, and the upregulation of adiponectin and other gene products. These curcumin-induced alterations reverse insulin resistance, hyperglycemia, hyperlipidemia, and other symptoms linked to obesity. Other structurally homologous nutraceuticals, derived from red chili, cinnamon, cloves, black pepper, and ginger, also exhibit effects against obesity and insulin resistance. PMID:20420526

  13. Diet-induced obesity modulates epigenetic responses to ionizing radiation in mice.

    PubMed

    Vares, Guillaume; Wang, Bing; Ishii-Ohba, Hiroko; Nenoi, Mitsuru; Nakajima, Tetsuo

    2014-01-01

    Both exposure to ionizing radiation and obesity have been associated with various pathologies including cancer. There is a crucial need in better understanding the interactions between ionizing radiation effects (especially at low doses) and other risk factors, such as obesity. In order to evaluate radiation responses in obese animals, C3H and C57BL/6J mice fed a control normal fat or a high fat (HF) diet were exposed to fractionated doses of X-rays (0.75 Gy ×4). Bone marrow micronucleus assays did not suggest a modulation of radiation-induced genotoxicity by HF diet. Using MSP, we observed that the promoters of p16 and Dapk genes were methylated in the livers of C57BL/6J mice fed a HF diet (irradiated and non-irradiated); Mgmt promoter was methylated in irradiated and/or HF diet-fed mice. In addition, methylation PCR arrays identified Ep300 and Socs1 (whose promoters exhibited higher methylation levels in non-irradiated HF diet-fed mice) as potential targets for further studies. We then compared microRNA regulations after radiation exposure in the livers of C57BL/6J mice fed a normal or an HF diet, using microRNA arrays. Interestingly, radiation-triggered microRNA regulations observed in normal mice were not observed in obese mice. miR-466e was upregulated in non-irradiated obese mice. In vitro free fatty acid (palmitic acid, oleic acid) administration sensitized AML12 mouse liver cells to ionizing radiation, but the inhibition of miR-466e counteracted this radio-sensitization, suggesting that the modulation of radiation responses by diet-induced obesity might involve miR-466e expression. All together, our results suggested the existence of dietary effects on radiation responses (especially epigenetic regulations) in mice, possibly in relationship with obesity-induced chronic oxidative stress.

  14. Obesity-Induced Neuroinflammation: Beyond the Hypothalamus.

    PubMed

    Guillemot-Legris, Owein; Muccioli, Giulio G

    2017-03-16

    Obesity is now a worldwide health issue. Far from being limited to weight gain, obesity is generally associated with low-grade inflammation and with a cluster of disorders collectively known as the 'metabolic syndrome'. When considering obesity and the subsequent neuroinflammation, the focus was long set on the hypothalamus. More recently, obesity-derived neuroinflammation has been shown to affect other brain structures such as the hippocampus, cortex, brainstem, or amygdala. Furthermore, obesity has been associated with increased occurrence of central disorders such as depression and impaired cognitive function. We discuss here the effects and mechanisms of obesity-derived neuroinflammation, with a specific emphasis on extra-hypothalamic structures, as well as the repercussions of neuroinflammation for some cerebral functions.

  15. Responses of brown adipose tissue to diet-induced obesity, exercise, dietary restriction and ephedrine treatment.

    PubMed

    Slocum, Nikki; Durrant, Jessica R; Bailey, David; Yoon, Lawrence; Jordan, Holly; Barton, Joanna; Brown, Roger H; Clifton, Lisa; Milliken, Tula; Harrington, Wallace; Kimbrough, Carie; Faber, Catherine A; Cariello, Neal; Elangbam, Chandikumar S

    2013-07-01

    Drug-induced weight loss in humans has been associated with undesirable side effects not present in weight loss from lifestyle interventions (caloric restriction or exercise). To investigate the mechanistic differences of weight loss by drug-induced and lifestyle interventions, we examined the gene expression (mRNA) in brown adipose tissue (BAT) and conducted histopathologic assessments in diet-induced obese (DIO) mice given ephedrine (18 mg/kg/day orally), treadmill exercise (10 m/min, 1-h/day), and dietary restriction (DR: 26% dietary restriction) for 7 days. Exercise and DR mice lost more body weight than controls and both ephedrine and exercise reduced percent body fat. All treatments reduced BAT and liver lipid accumulation (i.e., cytoplasmic lipids in brown adipocytes and hepatocytes) and increased oxygen consumption (VO2 ml/kg/h) compared with controls. Mitochondrial biogenesis/function-related genes (TFAM, NRF1 and GABPA) were up-regulated in the BAT of all groups. UCP-1 was up-regulated in exercise and ephedrine groups, whereas MFSD2A was up-regulated in ephedrine and DR groups. PGC-1α up-regulation was observed in exercise and DR groups but not in ephedrine group. In all experimental groups, except for ephedrine, fatty acid transport and metabolism genes were up-regulated, but the magnitude of change was higher in the DR group. PRKAA1 was up-regulated in all groups but not significantly in the ephedrine group. ADRß3 was slightly up-regulated in the DR group only, whereas ESRRA remained unchanged in all groups. Although our data suggest a common pathway of BAT activation elicited by ephedrine treatment, exercise or DR, mRNA changes were indicative of additional nutrient-sensing pathways in exercise and DR.

  16. Diet-induced obesity promotes myelopoiesis in hematopoietic stem cells

    PubMed Central

    Singer, Kanakadurga; DelProposto, Jennifer; Lee Morris, David; Zamarron, Brian; Mergian, Taleen; Maley, Nidhi; Cho, Kae Won; Geletka, Lynn; Subbaiah, Perla; Muir, Lindsey; Martinez-Santibanez, Gabriel; Nien-Kai Lumeng, Carey

    2014-01-01

    Obesity is associated with an activated macrophage phenotype in multiple tissues that contributes to tissue inflammation and metabolic disease. To evaluate the mechanisms by which obesity potentiates myeloid activation, we evaluated the hypothesis that obesity activates myeloid cell production from bone marrow progenitors to potentiate inflammatory responses in metabolic tissues. High fat diet-induced obesity generated both quantitative increases in myeloid progenitors as well as a potentiation of inflammation in macrophages derived from these progenitors. In vivo, hematopoietic stem cells from obese mice demonstrated the sustained capacity to preferentially generate inflammatory CD11c+ adipose tissue macrophages after serial bone marrow transplantation. We identified that hematopoietic MyD88 was important for the accumulation of CD11c+ adipose tissue macrophage accumulation by regulating the generation of myeloid progenitors from HSCs. These findings demonstrate that obesity and metabolic signals potentiate leukocyte production and that dietary priming of hematopoietic progenitors contributes to adipose tissue inflammation. PMID:25161889

  17. Simulated Microgravity Induces SOST/Sclerostin Upregulation in Osteocytes

    NASA Technical Reports Server (NTRS)

    Spatz, Jordan; Sibonga, Jean; Wu, Honglu; Barry, Kevin; Bouxsein, Mary; Pajevic, Paola Divieti

    2010-01-01

    Osteocytes are theorized to be the mechanosensors and transducers of mechanical forces in bone, yet the biological mechanism of this action remains elusive. Recent evidence suggests that SOST/Sclerostin is an important regulator of mechano-transduction. To investigate the molecular mechanisms of SOST/Sclerostin regulation under in-vitro and ex-vivo unloading we used the NASA Rotating Wall Vessel(RWV) Bioreactor. For in-vitro experiments, MLOY-4 osteocytic cells were seeded at a concentration of 250,000 cells onto 3D collagen scaffold (BD). Scaffolds (4 per condition) were either rotated in a vertical 50ml NASA/bioreactor vessel at 18 rpm (unloaded), cultured in a horizontal 50 ml NASA bioreactor vessel at 18 rpm (control for the sheared environment of vertical rotating vessel), or cultured in a static T-75 cm dish (static condition ) for 7days. For ex-vivo experiments, calvaria bones were harvested from 12-week old C57/Bl6 mice and sequentially digested with type I/II collagenase to remove periosteal osteoblasts. Calvaria halves (10 per condition) were then exposed to the same set of culture conditions described above. Simulated unloading, as achieved in the NASA RWV, resulted in enlarged, round osteocytes, as assessed by H&E staining, that was reminiscent of prior reports of unloading causing loss of osteocyte morphology and dendritic network connectivity. Semiquantitative realtime qPCR and immunohistochemistry from both in-vitro and ex-vivo RWV experiments demonstrated a four-fold up-regulation of SOST/Sclerostin. Furthermore, mRNA of the transcriptional SOST enhancer Mef2C was upregulated 1.4 fold in ex-vivo calvaria subjected to unloading conditions of the NASA RWV, suggesting that Mef2C might be an important regulator of mechano-sensation. These findings are consistent with results from seven day hindlimb unloading experiments, C57/B6 females, conducted in our laboratory and validate the use of the NASA RWV as a tool to study osteocyte mechanotransduction

  18. Deficiency of intestinal mucin-2 protects mice from diet-induced fatty liver disease and obesity

    PubMed Central

    Hartmann, Phillipp; Seebauer, Caroline T.; Mazagova, Magdalena; Horvath, Angela; Wang, Lirui; Llorente, Cristina; Varki, Nissi M.; Brandl, Katharina; Ho, Samuel B.

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) and obesity are characterized by altered gut microbiota, inflammation, and gut barrier dysfunction. Here, we investigated the role of mucin-2 (Muc2) as the major component of the intestinal mucus layer in the development of fatty liver disease and obesity. We studied experimental fatty liver disease and obesity induced by feeding wild-type and Muc2-knockout mice a high-fat diet (HFD) for 16 wk. Muc2 deficiency protected mice from HFD-induced fatty liver disease and obesity. Compared with wild-type mice, after a 16-wk HFD, Muc2-knockout mice exhibited better glucose homeostasis, reduced inflammation, and upregulated expression of genes involved in lipolysis and fatty acid β-oxidation in white adipose tissue. Compared with wild-type mice that were fed the HFD as well, Muc2-knockout mice also displayed higher intestinal and plasma levels of IL-22 and higher intestinal levels of the IL-22 target genes Reg3b and Reg3g. Our findings indicate that absence of the intestinal mucus layer activates the mucosal immune system. Higher IL-22 levels protect mice from diet-induced features of the metabolic syndrome. PMID:26702135

  19. Deficiency of intestinal mucin-2 protects mice from diet-induced fatty liver disease and obesity.

    PubMed

    Hartmann, Phillipp; Seebauer, Caroline T; Mazagova, Magdalena; Horvath, Angela; Wang, Lirui; Llorente, Cristina; Varki, Nissi M; Brandl, Katharina; Ho, Samuel B; Schnabl, Bernd

    2016-03-01

    Nonalcoholic fatty liver disease (NAFLD) and obesity are characterized by altered gut microbiota, inflammation, and gut barrier dysfunction. Here, we investigated the role of mucin-2 (Muc2) as the major component of the intestinal mucus layer in the development of fatty liver disease and obesity. We studied experimental fatty liver disease and obesity induced by feeding wild-type and Muc2-knockout mice a high-fat diet (HFD) for 16 wk. Muc2 deficiency protected mice from HFD-induced fatty liver disease and obesity. Compared with wild-type mice, after a 16-wk HFD, Muc2-knockout mice exhibited better glucose homeostasis, reduced inflammation, and upregulated expression of genes involved in lipolysis and fatty acid β-oxidation in white adipose tissue. Compared with wild-type mice that were fed the HFD as well, Muc2-knockout mice also displayed higher intestinal and plasma levels of IL-22 and higher intestinal levels of the IL-22 target genes Reg3b and Reg3g. Our findings indicate that absence of the intestinal mucus layer activates the mucosal immune system. Higher IL-22 levels protect mice from diet-induced features of the metabolic syndrome.

  20. Molecular Mechanisms of Obesity-Induced Osteoporosis and Muscle Atrophy

    PubMed Central

    Roy, Bipradas; Curtis, Mary E.; Fears, Letimicia S.; Nahashon, Samuel N.; Fentress, Hugh M.

    2016-01-01

    Obesity and osteoporosis are two alarming health disorders prominent among middle and old age populations, and the numbers of those affected by these two disorders are increasing. It is estimated that more than 600 million adults are obese and over 200 million people have osteoporosis worldwide. Interestingly, both of these abnormalities share some common features including a genetic predisposition, and a common origin: bone marrow mesenchymal stromal cells. Obesity is characterized by the expression of leptin, adiponectin, interleukin 6 (IL-6), interleukin 10 (IL-10), monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), macrophage colony stimulating factor (M-CSF), growth hormone (GH), parathyroid hormone (PTH), angiotensin II (Ang II), 5-hydroxy-tryptamine (5-HT), Advance glycation end products (AGE), and myostatin, which exert their effects by modulating the signaling pathways within bone and muscle. Chemical messengers (e.g., TNF-α, IL-6, AGE, leptins) that are upregulated or downregulated as a result of obesity have been shown to act as negative regulators of osteoblasts, osteocytes and muscles, as well as positive regulators of osteoclasts. These additive effects of obesity ultimately increase the risk for osteoporosis and muscle atrophy. The aim of this review is to identify the potential cellular mechanisms through which obesity may facilitate osteoporosis, muscle atrophy and bone fractures. PMID:27746742

  1. Chemotherapy can induce weight normalization of morbidly obese mice despite undiminished ingestion of high fat diet.

    PubMed

    Myers, Cheryl E; Hoelzinger, Dominique B; Truong, Tiffany N; Chew, Lindsey A; Myles, Arpita; Chaudhuri, Leena; Egan, Jan B; Liu, Jun; Gendler, Sandra J; Cohen, Peter A

    2017-01-17

    Morbidly obese patients who accomplish substantial weight loss often display a long-term decline in their resting metabolism, causing even relatively restrained caloric intake to trigger a relapse to the obese state. Paradoxically, we observed that morbidly obese mice receiving chemotherapy for cancer experienced spontaneous weight reduction despite unabated ingestion of their high fat diet (HFD). This response to chemotherapy could also be achieved in morbidly obese mice without cancer. Optimally dosed methotrexate (MTX) or cyclophosphamide (CY) enabled the mice to completely and safely normalize their body weight despite continued consumption of obesogenic quantities of HFD. Weight reduction was not attributable to decreased HFD intake, enhanced energy expenditure or malabsorption. MTX or CY dosing significantly depleted both adipose tissue and preadipocyte progenitors. Remarkably, however, despite continued high fat feeding, a compensatory increase in hepatocyte lipid storage was not observed, but rather the opposite. Gene microarray liver analyses demonstrated that HFD mice receiving MTX or CY experienced significantly inhibited lipogenesis and lipid storage, whereas Enho (energy homeostasis) gene expression was significantly upregulated. Further metabolic studies employing a human hepatocellular line revealed that MTX treatment preserved robust oxidative phosphorylation, but also promoted mitochondrial uncoupling with a surge in proton leak. This is the first report that certain optimally dosed chemotherapeutic agents can induce weight loss in morbidly obese mice without reduced dietary intake, apparently by depleting stores of adipocytes and their progenitors, curtailment of lipogenesis, and inconspicuous disposal of incoming dietary lipid via a steady state partial uncoupling of mitochondrial oxidative phosphorylation.

  2. Diet-induced obesity alters dendritic cell function in the presence and absence of tumor growth

    PubMed Central

    James, Britnie R.; Tomanek-Chalkley, Ann; Askeland, Eric J.; Kucaba, Tamara; Griffith, Thomas S.; Norian, Lyse A.

    2012-01-01

    Obesity is a mounting health concern in the United States, and is associated with an increased risk for developing several cancers, including renal cell carcinoma (RCC). Despite this, little is known regarding the impact of obesity on antitumor immunity. As dendritic cells (DC) are critical regulators of antitumor immunity, we examined the combined effects of obesity and tumor outgrowth on DC function. Using a diet-induced obesity (DIO) model, DC function was evaluated in mice bearing orthotopic RCC and in tumor-free controls. Tumor-free DIO mice had profoundly altered serum cytokine and chemokine profiles, with upregulation of 15 proteins, including IL-1α, IL-17, and LIF. Tumor-free DIO mice had elevated percentages of conventional splenic DC that were impaired in their ability to stimulate naive T cell expansion, although they were phenotypically similar to normal weight (NW) controls. In DIO mice, intra-renal RCC tumor challenge in the absence of therapy led to increased local infiltration by T cell-suppressive DC and accelerated early tumor outgrowth. Following administration of a DC-dependent immunotherapy, established RCC tumors regressed in NW mice. The same immunotherapy was ineffective in DIO mice, and was characterized by an accumulation of regulatory DC in tumor-bearing kidneys, decreased local infiltration by IFNγ-producing CD8 T cells, and progressive tumor outgrowth. Our results suggest that the presence of obesity as a co-morbidity can impair the efficacy of DC-dependent antitumor immunotherapies. PMID:22745381

  3. Diet-induced obesity alters dendritic cell function in the presence and absence of tumor growth.

    PubMed

    James, Britnie R; Tomanek-Chalkley, Ann; Askeland, Eric J; Kucaba, Tamara; Griffith, Thomas S; Norian, Lyse A

    2012-08-01

    Obesity is a mounting health concern in the United States and is associated with an increased risk for developing several cancers, including renal cell carcinoma (RCC). Despite this, little is known regarding the impact of obesity on antitumor immunity. Because dendritic cells (DC) are critical regulators of antitumor immunity, we examined the combined effects of obesity and tumor outgrowth on DC function. Using a diet-induced obesity (DIO) model, DC function was evaluated in mice bearing orthotopic RCC and in tumor-free controls. Tumor-free DIO mice had profoundly altered serum cytokine and chemokine profiles, with upregulation of 15 proteins, including IL-1α, IL-17, and LIF. Tumor-free DIO mice had elevated percentages of conventional splenic DC that were impaired in their ability to stimulate naive T cell expansion, although they were phenotypically similar to normal weight (NW) controls. In DIO mice, intrarenal RCC tumor challenge in the absence of therapy led to increased local infiltration by T cell-suppressive DC and accelerated early tumor outgrowth. Following administration of a DC-dependent immunotherapy, established RCC tumors regressed in normal weight mice. The same immunotherapy was ineffective in DIO mice and was characterized by an accumulation of regulatory DC in tumor-bearing kidneys, decreased local infiltration by IFN-γ-producing CD8 T cells, and progressive tumor outgrowth. Our results suggest that the presence of obesity as a comorbidity can impair the efficacy of DC-dependent antitumor immunotherapies.

  4. Arginase inhibition ameliorates adipose tissue inflammation in mice with diet-induced obesity.

    PubMed

    Hu, Huan; Moon, Jiyoung; Chung, Ji Hyung; Kim, Oh Yoen; Yu, Rina; Shin, Min-Jeong

    2015-08-28

    This study examined whether oral administration of an arginase inhibitor regulates adipose tissue macrophage infiltration and inflammation in mice with high fat diet (HFD)-induced obesity. Male C57BL/6 mice (n = 30) were randomly assigned to control (CTL, n = 10), HFD only (n = 10), and HFD with arginase inhibitor N(ω)-hydroxy-nor-l-arginine (HFD with nor-NOHA, n = 10) groups. Plasma and mRNA levels of cytokines in epididymal adipose tissues (EAT), macrophage infiltration into EAT, and macrophage phenotype polarization were measured in the animals after 12 weeks. Additionally, the effects of nor-NOHA on adipose tissue macrophage infiltration and mRNA expression of cytokines were measured in co-cultured 3T3-L1 adipocytes and RAW 264.7 macrophages. Macrophage infiltration into the adipocytes was significantly suppressed by nor-NOHA treatment in adipocyte/macrophage co-culture system and mice with HFD-induced obesity. Pro-inflammatory cytokines, including monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6), were significantly downregulated, and the anti-inflammatory cytokine IL-10 was significantly upregulated in nor-NOHA-treated co-cultured cells. In the mice with HFD-induced obesity, plasma and mRNA levels of MCP-1 significantly reduced after supplementation with nor-NOHA. In addition, oral supplement of nor-NOHA modified M1/M2 phenotype ratio in the EAT. Oral supplementation of an arginase inhibitor, nor-NOHA, altered M1/M2 macrophage phenotype and macrophage infiltration into HFD-induced obese adipose tissue, thereby improved adipose tissue inflammatory response. These results may indicate that arginase inhibition ameliorates obesity-induced adipose tissue inflammation.

  5. Death Inducer-Obliterator 1 Triggers Apoptosis after Nuclear Translocation and Caspase Upregulation

    PubMed Central

    García-Domingo, David; Ramírez, Dorian; González de Buitrago, Gonzalo; Martínez-A, Carlos

    2003-01-01

    Death inducer-obliterator 1 (DIO-1) is a gene that is upregulated early in apoptosis. Here we report that in healthy cells, the DIO-1 gene product was located in the cytoplasm, where it formed oligomers. After interleukin-3 starvation or c-Myc-induced apoptosis in serum-free conditions, DIO-1 translocated to the nucleus, where it upregulated caspase levels and activity. A nuclear localization signal deletion mutant (DIO-1ΔNLS) was unable to translocate to the nuclear compartment in the absence of interleukin-3 and failed to upregulate procaspase levels or trigger cell death. In addition, cells stably expressing DIO-1ΔNLS were protected from apoptosis induced by interleukin-3 withdrawal. These results indicate that DIO-1 has a relevant role in regulating the early stages of cell death. PMID:12697821

  6. Dimethyl Fumarate Induces Glutathione Recycling by Upregulation of Glutathione Reductase

    PubMed Central

    Hoffmann, Christina; Dietrich, Michael; Herrmann, Ann-Kathrin; Schacht, Teresa

    2017-01-01

    Neuronal degeneration in multiple sclerosis has been linked to oxidative stress. Dimethyl fumarate (DMF) is an effective oral therapeutic option shown to reduce disease activity and progression in patients with relapsing-remitting multiple sclerosis. DMF activates the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) leading to increased synthesis of the major cellular antioxidant glutathione (GSH) and prominent neuroprotection in vitro. We previously demonstrated that DMF is capable of raising GSH levels even when glutathione synthesis is inhibited, suggesting enhanced GSH recycling. Here, we found that DMF indeed induces glutathione reductase (GSR), a homodimeric flavoprotein that catalyzes GSSG reduction to GSH by using NADPH as a reducing cofactor. Knockdown of GSR using a pool of E. coli RNase III-digested siRNAs or pharmacological inhibition of GSR, however, also induced the antioxidant response rendering it impossible to verify the suspected attenuation of DMF-mediated neuroprotection. However, in cystine-free medium, where GSH synthesis is abolished, pharmacological inhibition of GSR drastically reduced the effect of DMF on glutathione recycling. We conclude that DMF increases glutathione recycling through induction of glutathione reductase. PMID:28116039

  7. High fat diet-fed obese rats are highly sensitive to doxorubicin-induced cardiotoxicity

    SciTech Connect

    Mitra, Mayurranjan S.; Donthamsetty, Shashikiran; White, Brent; Mehendale, Harihara M.

    2008-09-15

    Often, chemotherapy by doxorubicin (Adriamycin) is limited due to life threatening cardiotoxicity in patients during and posttherapy. Recently, we have shown that moderate diet restriction remarkably protects against doxorubicin-induced cardiotoxicity. This cardioprotection is accompanied by decreased cardiac oxidative stress and triglycerides and increased cardiac fatty-acid oxidation, ATP synthesis, and upregulated JAK/STAT3 pathway. In the current study, we investigated whether a physiological intervention by feeding 40% high fat diet (HFD), which induces obesity in male Sprague-Dawley rats (250-275 g), sensitizes to doxorubicin-induced cardiotoxicity. A LD{sub 10} dose (8 mg doxorubicin/kg, ip) administered on day 43 of the HFD feeding regimen led to higher cardiotoxicity, cardiac dysfunction, lipid peroxidation, and 80% mortality in the obese (OB) rats in the absence of any significant renal or hepatic toxicity. Doxorubicin toxicokinetics studies revealed no change in accumulation of doxorubicin and doxorubicinol (toxic metabolite) in the normal diet-fed (ND) and OB hearts. Mechanistic studies revealed that OB rats are sensitized due to: (1) higher oxyradical stress leading to upregulation of uncoupling proteins 2 and 3, (2) downregulation of cardiac peroxisome proliferators activated receptor-{alpha}, (3) decreased plasma adiponectin levels, (4) decreased cardiac fatty-acid oxidation (666.9 {+-} 14.0 nmol/min/g heart in ND versus 400.2 {+-} 11.8 nmol/min/g heart in OB), (5) decreased mitochondrial AMP-{alpha}2 protein kinase, and (6) 86% drop in cardiac ATP levels accompanied by decreased ATP/ADP ratio after doxorubicin administration. Decreased cardiac erythropoietin and increased SOCS3 further downregulated the cardioprotective JAK/STAT3 pathway. In conclusion, HFD-induced obese rats are highly sensitized to doxorubicin-induced cardiotoxicity by substantially downregulating cardiac mitochondrial ATP generation, increasing oxidative stress and downregulating

  8. Monomeric Tartrate Resistant Acid Phosphatase Induces Insulin Sensitive Obesity

    PubMed Central

    Lång, Pernilla; van Harmelen, Vanessa; Rydén, Mikael; Kaaman, Maria; Parini, Paolo; Carneheim, Claes; Cassady, A. Ian; Hume, David A.; Andersson, Göran; Arner, Peter

    2008-01-01

    Background Obesity is associated with macrophage infiltration of adipose tissue, which may link adipose inflammation to insulin resistance. However, the impact of inflammatory cells in the pathophysiology of obesity remains unclear. Tartrate resistant acid phosphatase (TRAP) is an enzyme expressed by subsets of macrophages and osteoclasts that exists either as an enzymatically inactive monomer or as an active, proteolytically processed dimer. Principal Findings Using mice over expressing TRAP, we show that over-expression of monomeric, but not the dimeric form in adipose tissue leads to early onset spontaneous hyperplastic obesity i.e. many small fat cells. In vitro, recombinant monomeric, but not proteolytically processed TRAP induced proliferation and differentiation of mouse and human adipocyte precursor cells. In humans, monomeric TRAP was highly expressed in the adipose tissue of obese individuals. In both the mouse model and in the obese humans the source of TRAP in adipose tissue was macrophages. In addition, the obese TRAP over expressing mice exhibited signs of a low-grade inflammatory reaction in adipose tissue without evidence of abnormal adipocyte lipolysis, lipogenesis or insulin sensitivity. Conclusion Monomeric TRAP, most likely secreted from adipose tissue macrophages, induces hyperplastic obesity with normal adipocyte lipid metabolism and insulin sensitivity. PMID:18320034

  9. Obesity-induced increases in sympathetic nerve activity: sex matters.

    PubMed

    Brooks, Virginia L; Shi, Zhigang; Holwerda, Seth W; Fadel, Paul J

    2015-01-01

    Abundant evidence obtained largely from male human and animal subjects indicates that obesity increases sympathetic nerve activity (SNA), which contributes to hypertension development. However, recent studies that included women reported that the strong relationships between muscle SNA and waist circumference or body mass index (BMI) found in men are not present in overweight and obese women. A similar sex difference in the association between adiposity and hypertension development has been identified in animal models of obesity. In this brief review, we consider two possible mechanisms for this sex difference. First, visceral adiposity, leptin, insulin, and angiotensin II have been identified as potential culprits in obesity-induced sympathoexcitation in males. We explore if these factors wield the same impact in females. Second, we consider if sex differences in vascular reactivity to sympathetic activation contribute. Our survey of the literature suggests that premenopausal females may be able to resist obesity-induced sympathoexcitation and hypertension in part due to differences in adipose disposition as well as its muted inflammatory response and reduced production of pressor versus depressor components of the renin-angiotensin system. In addition, vascular responsiveness to increased SNA may be reduced. However, more importantly, we identify the urgent need for further study, not only of sex differences per se, but also of the mechanisms that may mediate these differences. This information is required not only to refine treatment options for obese premenopausal women but also to potentially reveal new therapeutic avenues in obese men and women.

  10. Berberine inhibits adipogenesis in high-fat diet-induced obesity mice.

    PubMed

    Hu, Yueshan; Davies, Gareth E

    2010-07-01

    Our previous studies illustrated that berberine inhibited adipogenesis in murine-derived 3T3-L1 preadipocytes and human white preadipocytes. In this study, the effects of berberine on the adipogenesis of high-fat diet-induced obesity (FD) or normal diet (ND) mice and possible transcriptional impact are investigated. The results demonstrated that in FD mice, berberine reduced mouse weight gain and food intake and serum glucose, triglyceride, and total cholesterol levels accompanied with a down-regulation of PPARgamma expression and an up-regulation of GATA-3 expression. Berberine had no adverse effects on ND mice. These encouraging findings suggest that berberine has excellent pharmacological potential to prevent obesity.

  11. Connection of Nicotine to Diet-Induced Obesity and Non-Alcoholic Fatty Liver Disease: Cellular and Mechanistic Insights

    PubMed Central

    Sinha-Hikim, Amiya P.; Sinha-Hikim, Indrani; Friedman, Theodore C.

    2017-01-01

    Non-alcoholic fatty liver disease (NAFLD) poses a serious health hazard affecting 20–40% of adults in the general population in the USA and over 70% of the obese and extremely obese people. In addition to obesity, nicotine is recognized as a risk factor for NAFLD, and it has been reported that nicotine can exaggerate obesity-induced hepatic steatosis. The development of NAFLD has serious clinical complications because of its potential progression from simple hepatic steatosis to non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. Multiple mechanisms can be involved in nicotine plus high-fat diet-induced (HFD) hepatic steatosis. Emerging evidence now suggests that nicotine exacerbates hepatic steatosis triggered by HFD, through increased oxidative stress and hepatocellular apoptosis, decreased phosphorylation (inactivation) of adenosine-5-monophosphate-activated protein kinase and, in turn, up-regulation of sterol response-element binding protein 1-c, fatty acid synthase, and activation of acetyl-coenzyme A-carboxylase, leading to increased hepatic lipogenesis. There is also growing evidence that chronic endoplasmic reticulum stress through regulation of several pathways leading to oxidative stress, inflammation, perturbed hepatic lipid homeostasis, apoptosis, and autophagy can induce hepatic steatosis and its progression to NASH. Evidence also suggests a central role of the gut microbiota in obesity and its related disorders, including NAFLD. This review explores the contribution of nicotine and obesity to the development of NAFLD and its molecular underpinning. PMID:28239368

  12. Noninflammatory upregulation of nerve growth factor underlies gastric hypersensitivity induced by neonatal colon inflammation

    PubMed Central

    Li, Qingjie; Winston, John H.

    2015-01-01

    Gastric hypersensitivity is one of the key contributors to the postprandial symptoms of epigastric pain/discomfort, satiety, and fullness in functional dyspepsia patients. Epidemiological studies found that adverse early-life experiences are risk factors for the development of gastric hypersensitivity. Preclinical studies found that neonatal colon inflammation elevates plasma norepinephrine (NE), which upregulates expression of nerve growth factor (NGF) in the muscularis externa of the gastric fundus. Our goal was to investigate the cellular mechanisms by which NE upregulates the expression of NGF in gastric hypersensitive (GHS) rats, which were subjected previously to neonatal colon inflammation. Neonatal colon inflammation upregulated NGF protein, but not mRNA, in the gastric fundus of GHS rats. Western blotting showed upregulation of p110γ of phosphatidylinositol 4,5-bisphosphate 3-kinase (PI3K), phosphoinositide-dependent kinase-1 (PDK1), pAKT(Ser473), and phosphorylated 4E-binding protein (p4E-BP1)(Thr70), suggesting AKT activation and enhanced NGF protein translation. AKT inhibitor MK-2206 blocked the upregulation of NGF in the fundus of GHS rats. Matrix metalloproteinase 9 (MMP-9), the major NGF-degrading protease, was suppressed, indicating that NGF degradation was impeded. Incubation of fundus muscularis externa with NE upregulated NGF by modulating the protein translation and degradation pathways. Yohimbine, an α2-adrenergic receptor antagonist, upregulated plasma NE and NGF expression by activating the protein translation and degradation pathways in naive rats. In contrast, a cocktail of adrenergic receptor antagonists suppressed the upregulation of NGF by blocking the activation of the protein translation and degradation pathways. Our findings provide evidence that the elevation of plasma NE induces NGF expression in the gastric fundus. PMID:26608656

  13. Obesity impairs lactation performance in mice by inducing prolactin resistance

    PubMed Central

    Buonfiglio, Daniella C.; Ramos-Lobo, Angela M.; Freitas, Vanessa M.; Zampieri, Thais T.; Nagaishi, Vanessa S.; Magalhães, Magna; Cipolla-Neto, Jose; Cella, Nathalie; Donato Jr., Jose

    2016-01-01

    Obesity reduces breastfeeding success and lactation performance in women. However, the mechanisms involved are not entirely understood. In the present study, female C57BL/6 mice were chronically exposed to a high-fat diet to induce obesity and subsequently exhibited impaired offspring viability (only 15% survival rate), milk production (33% reduction), mammopoiesis (one-third of the glandular area compared to control animals) and postpartum maternal behaviors (higher latency to retrieving and grouping the pups). Reproductive experience attenuated these defects. Diet-induced obese mice exhibited high basal pSTAT5 levels in the mammary tissue and hypothalamus, and an acute prolactin stimulus was unable to further increase pSTAT5 levels above basal levels. In contrast, genetically obese leptin-deficient females showed normal prolactin responsiveness. Additionally, we identified the expression of leptin receptors specifically in basal/myoepithelial cells of the mouse mammary gland. Finally, high-fat diet females exhibited altered mRNA levels of ERBB4 and NRG1, suggesting that obesity may involve disturbances to mammary gland paracrine circuits that are critical in the control of luminal progenitor function and lactation. In summary, our findings indicate that high leptin levels are a possible cause of the peripheral and central prolactin resistance observed in obese mice which leads to impaired lactation performance. PMID:26926925

  14. P53-dependent upregulation of neutral sphingomyelinase-2: role in doxorubicin-induced growth arrest

    PubMed Central

    Shamseddine, A A; Clarke, C J; Carroll, B; Airola, M V; Mohammed, S; Rella, A; Obeid, L M; Hannun, Y A

    2015-01-01

    Neutral sphingomyelinase-2 (nSMase2) is a ceramide-generating enzyme that has been implicated in growth arrest, apoptosis and exosome secretion. Although previous studies have reported transcriptional upregulation of nSMase2 in response to daunorubicin, through Sp1 and Sp3 transcription factors, the role of the DNA damage pathway in regulating nSMase2 remains unclear. In this study, we show that doxorubicin induces a dose-dependent induction of nSMase2 mRNA and protein with concomitant increases in nSMase activity and ceramide levels. Upregulation of nSMase2 was dependent on ATR, Chk1 and p53, thus placing it downstream of the DNA damage pathway. Moreover, overexpression of p53 was sufficient to transcriptionally induce nSMase2, without the need for DNA damage. DNA-binding mutants as well as acetylation mutants of p53 were unable to induce nSMase2, suggesting a role of nSMase2 in growth arrest. Moreover, knockdown of nSMase2 prevented doxorubicin-induced growth arrest. Finally, p53-induced nSMase2 upregulation appears to occur via a novel transcription start site upstream of exon 3. These results identify nSMase2 as a novel p53 target gene, regulated by the DNA damage pathway to induce cell growth arrest. PMID:26512957

  15. Effect of Peucedanum japonicum Thunb extract on high-fat diet-induced obesity and gene expression in mice.

    PubMed

    Nukitrangsan, Natthanan; Okabe, Takafumi; Toda, Takayoshi; Inafuku, Masashi; Iwasaki, Hironori; Oku, Hirosuke

    2012-01-01

    Supplementation of the diet with Peucedanum japonicum Thunb (PJT) powder inhibits high-fat diet-induced obesity in mice. Either the fiber component or other bioactive components in the PJT powder may inhibit obesity. This study, therefore, was an attempt to identify the components, fiber or other phytochemicals of PJT that were responsible for the anti-obesity activity, and also studied the modulation of obesity-related gene expression in C57BL/6 mice. Animals were fed a modified-AIN76 diet supplemented with PJT powder or extracts of PJT in water, 50 % ethanol, or ethanol. Body weight gain, tissue weight, serum biochemical parameters, liver lipid concentrations, and gene expression in tissues were compared between the control and treatment groups. Of the extracts, the ethanol extract of PJT decreased fat accumulation and adipocyte size, reduced serum and liver triglyceride concentrations, and inhibited obesity. This finding clearly demonstrates the presence of anti-obesity phytochemicals in PJT. Ethanol extract of PJT inhibited lipase activity in vitro. Modulation of gene expression by PJT ethanol extract was largely similar to that by PJT powder in the hepatic and adipose tissues: RORC and PBEF1 were upregulated and DUSP1, INSIG2, and SERPINA12 were downregulated in the liver; FXRα and PPARγ were upregulated and PEG1/MEST, the size-marker of adipocytes, was downregulated in the adipose tissue. Furthermore, PJT ethanol extract increased the expression of the UCP3 gene in muscle. These results suggest that the anti-obesity phytochemicals in PJT lower lipid levels by inhibiting fat absorption and by modulating obesity-related gene expression in the liver, adipose tissue, and muscle.

  16. Obesity decreases serum selenium levels in DMBA-induced mammary tumor using Obese Zucker Rat Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, we reported that obese Zucker rats had increased susceptibility to DMBA-induced mammary tumors compared to lean Zucker rats. Several studies suggest that lower serum selenium may play an important role in increasing the risk of several types of cancers (e.g, colon, breast and prostate canc...

  17. High-density lipoprotein inhibits ox-LDL-induced adipokine secretion by upregulating SR-BI expression and suppressing ER Stress pathway.

    PubMed

    Song, Guohua; Wu, Xia; Zhang, Pu; Yu, Yang; Yang, Mingfeng; Jiao, Peng; Wang, Ni; Song, Haiming; Wu, You; Zhang, Xiangjian; Liu, Huaxia; Qin, Shucun

    2016-07-29

    Endoplasmic reticulum stress (ERS) in adipocytes can modulate adipokines secretion. The aim of this study was to explore the protective effect of high-density lipoprotein (HDL) on oxidized low-density lipoprotein (ox-LDL)-induced ERS-C/EBP homologous protein (CHOP) pathway-mediated adipokine secretion. Our results showed that serum adipokines, including visfatin, resistin and TNF-α, correlated inversely with serum HDL cholesterol level in patients with abdominal obesity. In vitro, like ERS inhibitor 4-phenylbutyric acid (PBA), HDL inhibited ox-LDL- or tunicamycin (TM, an ERS inducer)-induced increase in visfatin and resistin secretion. Moreover, HDL inhibited ox-LDL-induced free cholesterol (FC) accumulation in whole cell lysate and in the endoplasmic reticulum. Additionally, like PBA, HDL inhibited ox-LDL- or TM-induced activation of ERS response as assessed by the decreased phosphorylation of protein kinase-like ER kinase and eukaryotic translation initiation factor 2α and reduced nuclear translocation of activating transcription factor 6 as well as the downregulation of Bip and CHOP. Furthermore, HDL increased scavenger receptor class B type I (SR-BI) expression and SR-BI siRNA treatment abolished the inhibitory effects of HDL on ox-LDL-induced FC accumulation and CHOP upregulation. These data indicate that HDL may suppress ox-LDL-induced FC accumulation in adipocytes through upregulation of SR-BI, subsequently preventing ox-LDL-induced ER stress-CHOP pathway-mediated adipocyte inflammation.

  18. High-density lipoprotein inhibits ox-LDL-induced adipokine secretion by upregulating SR-BI expression and suppressing ER Stress pathway

    PubMed Central

    Song, Guohua; Wu, Xia; Zhang, Pu; Yu, Yang; Yang, Mingfeng; Jiao, Peng; Wang, Ni; Song, Haiming; Wu, You; Zhang, Xiangjian; Liu, Huaxia; Qin, Shucun

    2016-01-01

    Endoplasmic reticulum stress (ERS) in adipocytes can modulate adipokines secretion. The aim of this study was to explore the protective effect of high-density lipoprotein (HDL) on oxidized low-density lipoprotein (ox-LDL)-induced ERS-C/EBP homologous protein (CHOP) pathway-mediated adipokine secretion. Our results showed that serum adipokines, including visfatin, resistin and TNF-α, correlated inversely with serum HDL cholesterol level in patients with abdominal obesity. In vitro, like ERS inhibitor 4-phenylbutyric acid (PBA), HDL inhibited ox-LDL- or tunicamycin (TM, an ERS inducer)-induced increase in visfatin and resistin secretion. Moreover, HDL inhibited ox-LDL-induced free cholesterol (FC) accumulation in whole cell lysate and in the endoplasmic reticulum. Additionally, like PBA, HDL inhibited ox-LDL- or TM-induced activation of ERS response as assessed by the decreased phosphorylation of protein kinase-like ER kinase and eukaryotic translation initiation factor 2α and reduced nuclear translocation of activating transcription factor 6 as well as the downregulation of Bip and CHOP. Furthermore, HDL increased scavenger receptor class B type I (SR-BI) expression and SR-BI siRNA treatment abolished the inhibitory effects of HDL on ox-LDL-induced FC accumulation and CHOP upregulation. These data indicate that HDL may suppress ox-LDL-induced FC accumulation in adipocytes through upregulation of SR-BI, subsequently preventing ox-LDL-induced ER stress-CHOP pathway-mediated adipocyte inflammation. PMID:27468698

  19. Obesity induces a phenotypic switch in adipose tissue macrophage polarization.

    PubMed

    Lumeng, Carey N; Bodzin, Jennifer L; Saltiel, Alan R

    2007-01-01

    Adipose tissue macrophages (ATMs) infiltrate adipose tissue during obesity and contribute to insulin resistance. We hypothesized that macrophages migrating to adipose tissue upon high-fat feeding may differ from those that reside there under normal diet conditions. To this end, we found a novel F4/80(+)CD11c(+) population of ATMs in adipose tissue of obese mice that was not seen in lean mice. ATMs from lean mice expressed many genes characteristic of M2 or "alternatively activated" macrophages, including Ym1, arginase 1, and Il10. Diet-induced obesity decreased expression of these genes in ATMs while increasing expression of genes such as those encoding TNF-alpha and iNOS that are characteristic of M1 or "classically activated" macrophages. Interestingly, ATMs from obese C-C motif chemokine receptor 2-KO (Ccr2-KO) mice express M2 markers at levels similar to those from lean mice. The antiinflammatory cytokine IL-10, which was overexpressed in ATMs from lean mice, protected adipocytes from TNF-alpha-induced insulin resistance. Thus, diet-induced obesity leads to a shift in the activation state of ATMs from an M2-polarized state in lean animals that may protect adipocytes from inflammation to an M1 proinflammatory state that contributes to insulin resistance.

  20. Obesity induces a phenotypic switch in adipose tissue macrophage polarization

    PubMed Central

    Lumeng, Carey N.; Bodzin, Jennifer L.; Saltiel, Alan R.

    2007-01-01

    Adipose tissue macrophages (ATMs) infiltrate adipose tissue during obesity and contribute to insulin resistance. We hypothesized that macrophages migrating to adipose tissue upon high-fat feeding may differ from those that reside there under normal diet conditions. To this end, we found a novel F4/80+CD11c+ population of ATMs in adipose tissue of obese mice that was not seen in lean mice. ATMs from lean mice expressed many genes characteristic of M2 or “alternatively activated” macrophages, including Ym1, arginase 1, and Il10. Diet-induced obesity decreased expression of these genes in ATMs while increasing expression of genes such as those encoding TNF-α and iNOS that are characteristic of M1 or “classically activated” macrophages. Interestingly, ATMs from obese C-C motif chemokine receptor 2–KO (Ccr2-KO) mice express M2 markers at levels similar to those from lean mice. The antiinflammatory cytokine IL-10, which was overexpressed in ATMs from lean mice, protected adipocytes from TNF-α–induced insulin resistance. Thus, diet-induced obesity leads to a shift in the activation state of ATMs from an M2-polarized state in lean animals that may protect adipocytes from inflammation to an M1 proinflammatory state that contributes to insulin resistance. PMID:17200717

  1. Adaptive upregulation of Clumping Factor A (ClfA) by S. aureus in the obese, type 2 diabetic host mediates increased virulence.

    PubMed

    Farnsworth, Christopher W; Schott, Eric M; Jensen, Sarah E; Zukoski, Jacob; Benvie, Abigail M; Refaai, Majed A; Kates, Stephen L; Schwarz, Edward M; Zuscik, Michael J; Gill, Steven R; Mooney, Robert A

    2017-03-20

    Obesity and associated type 2 diabetes (T2D) are important risk factors for infection following orthopaedic implant surgery. Staphylococcus aureus, the most common pathogen in bone infections, adapts to multiple environments to survive and evade host immune responses. Whether adaptation of S. aureus to the unique environment of the obese/T2D host accounts for its increased virulence and persistence in this population is unknown. Thus, we assessed implant-associated osteomyelitis in normal versus high fat-diet obese/T2D mice and found that S. aureus infection was more severe, including increases in bone abscesses relative to non-diabetic controls. S. aureus isolated from bone of obese/T2D mice displayed marked upregulation of four adhesion genes (clfA, clfB, bbp, and sdrC), all with binding affinity for fibrin(ogen). Immunostaining of infected bone revealed increased fibrin deposition surrounding bacterial abscesses in obese/T2D mice. In vitro coagulation assays demonstrated a hypercoagulable state in obese/T2D mice that was comparable to that of diabetic patients. S. aureus with an inactivating mutation in clumping factor A (clfA) showed a reduction in bone infection severity that eliminated the effect of obesity/T2D, while infections in control mice were unchanged. In infected mice that overexpress plasminogen activator inhibitor-1 (PAI-1), S. aureusclfA expression and fibrin-encapsulated abscess communities in bone were also increased, further linking fibrin deposition to S. aureus expression of clfA and infection severity. Together, these results demonstrate an adaptation by S. aureus to obesity/T2D with increased expression of clfA that is associated with the hypercoagulable state of the host and increased virulence of S. aureus.

  2. Stress-induced obesity and the emotional nervous system.

    PubMed

    Dallman, Mary F

    2010-03-01

    Stress and emotional brain networks foster eating behaviors that can lead to obesity. The neural networks underlying the complex interactions among stressors, body, brain and food intake are now better understood. Stressors, by activating a neural stress-response network, bias cognition toward increased emotional activity and degraded executive function. This causes formed habits to be used rather than a cognitive appraisal of responses. Stress also induces secretion of glucocorticoids, which increases motivation for food, and insulin, which promotes food intake and obesity. Pleasurable feeding then reduces activity in the stress-response network, reinforcing the feeding habit. These effects of stressors emphasize the importance of teaching mental reappraisal techniques to restore responses from habitual to thoughtful, thus battling stress-induced obesity.

  3. Fish oil intake induces UCP1 upregulation in brown and white adipose tissue via the sympathetic nervous system

    PubMed Central

    Kim, Minji; Goto, Tsuyoshi; Yu, Rina; Uchida, Kunitoshi; Tominaga, Makoto; Kano, Yuriko; Takahashi, Nobuyuki; Kawada, Teruo

    2015-01-01

    Brown adipose tissue (BAT) plays a central role in regulating energy homeostasis, and may provide novel strategies for the treatment of human obesity. BAT-mediated thermogenesis is regulated by mitochondrial uncoupling protein 1 (UCP1) in classical brown and ectopic beige adipocytes, and is controlled by sympathetic nervous system (SNS). Previous work indicated that fish oil intake reduces fat accumulation and induces UCP1 expression in BAT; however, the detailed mechanism of this effect remains unclear. In this study, we investigated the effect of fish oil on energy expenditure and the SNS. Fish oil intake increased oxygen consumption and rectal temperature, with concomitant upregulation of UCP1 and the β3 adrenergic receptor (β3AR), two markers of beige adipocytes, in the interscapular BAT and inguinal white adipose tissue (WAT). Additionally, fish oil intake increased the elimination of urinary catecholamines and the noradrenaline (NA) turnover rate in interscapular BAT and inguinal WAT. Furthermore, the effects of fish oil on SNS-mediated energy expenditure were abolished in transient receptor potential vanilloid 1 (TRPV1) knockout mice. In conclusion, fish oil intake can induce UCP1 expression in classical brown and beige adipocytes via the SNS, thereby attenuating fat accumulation and ameliorating lipid metabolism. PMID:26673120

  4. Fish oil intake induces UCP1 upregulation in brown and white adipose tissue via the sympathetic nervous system.

    PubMed

    Kim, Minji; Goto, Tsuyoshi; Yu, Rina; Uchida, Kunitoshi; Tominaga, Makoto; Kano, Yuriko; Takahashi, Nobuyuki; Kawada, Teruo

    2015-12-17

    Brown adipose tissue (BAT) plays a central role in regulating energy homeostasis, and may provide novel strategies for the treatment of human obesity. BAT-mediated thermogenesis is regulated by mitochondrial uncoupling protein 1 (UCP1) in classical brown and ectopic beige adipocytes, and is controlled by sympathetic nervous system (SNS). Previous work indicated that fish oil intake reduces fat accumulation and induces UCP1 expression in BAT; however, the detailed mechanism of this effect remains unclear. In this study, we investigated the effect of fish oil on energy expenditure and the SNS. Fish oil intake increased oxygen consumption and rectal temperature, with concomitant upregulation of UCP1 and the β3 adrenergic receptor (β3AR), two markers of beige adipocytes, in the interscapular BAT and inguinal white adipose tissue (WAT). Additionally, fish oil intake increased the elimination of urinary catecholamines and the noradrenaline (NA) turnover rate in interscapular BAT and inguinal WAT. Furthermore, the effects of fish oil on SNS-mediated energy expenditure were abolished in transient receptor potential vanilloid 1 (TRPV1) knockout mice. In conclusion, fish oil intake can induce UCP1 expression in classical brown and beige adipocytes via the SNS, thereby attenuating fat accumulation and ameliorating lipid metabolism.

  5. TLR4 signaling induces TLR3 up-regulation in alveolar macrophages during acute lung injury

    PubMed Central

    Ding, Xibing; Jin, Shuqing; Tong, Yao; Jiang, Xi; Chen, Zhixia; Mei, Shuya; Zhang, Liming; Billiar, Timothy R.; Li, Quan

    2017-01-01

    Acute lung injury is a life-threatening inflammatory response caused by severe infection. Toll-like receptors in alveolar macrophages (AMΦ) recognize the molecular constituents of pathogens and activate the host’s innate immune responses. Numerous studies have documented the importance of TLR-TLR cross talk, but few studies have specifically addressed the relationship between TLR4 and TLR3. We explored a novel mechanism of TLR3 up-regulation that is induced by LPS-TLR4 signaling in a dose- and time-dependent manner in AMΦ from C57BL/6 mice, while the LPS-induced TLR3 expression was significantly reduced in TLR4−/− and Myd88−/− mice and following pretreatment with a NF-κB inhibitor. The enhanced TLR3 up-regulation in AMΦ augmented the expression of cytokines and chemokines in response to sequential challenges with LPS and Poly I:C, a TLR3 ligand, which was physiologically associated with amplified AMΦ-induced PMN migration into lung alveoli. Our study demonstrates that the synergistic effect between TLR4 and TLR3 in macrophages is an important determinant in acute lung injury and, more importantly, that TLR3 up-regulation is dependent on TLR4-MyD88-NF-κB signaling. These results raise the possibility that bacterial infections can induce sensitivity to viral infections, which may have important implications for the therapeutic manipulation of the innate immune system. PMID:28198368

  6. The obesity-induced transcriptional regulator TRIP-Br2 mediates visceral fat endoplasmic reticulum stress-induced inflammation

    PubMed Central

    Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee

    2016-01-01

    The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that—given that these pathways are conserved in humans—might serve as potential therapeutic targets in obesity. PMID:27109496

  7. Diet-induced obesity causes peripheral and central ghrelin resistance by promoting inflammation.

    PubMed

    Naznin, Farhana; Toshinai, Koji; Waise, T M Zaved; NamKoong, Cherl; Md Moin, Abu Saleh; Sakoda, Hideyuki; Nakazato, Masamitsu

    2015-07-01

    Ghrelin, a stomach-derived orexigenic peptide, transmits starvation signals to the hypothalamus via the vagus afferent nerve. Peripheral administration of ghrelin does not induce food intake in high fat diet (HFD)-induced obese mice. We investigated whether this ghrelin resistance was caused by dysfunction of the vagus afferent pathway. Administration (s.c.) of ghrelin did not induce food intake, suppression of oxygen consumption, electrical activity of the vagal afferent nerve, phosphorylation of ERK2 and AMP-activated protein kinase alpha in the nodose ganglion, or Fos expression in hypothalamic arcuate nucleus of mice fed a HFD for 12 weeks. Administration of anti-ghrelin IgG did not induce suppression of food intake in HFD-fed mice. Expression levels of ghrelin receptor mRNA in the nodose ganglion and hypothalamus of HFD-fed mice were reduced. Inflammatory responses, including upregulation of macrophage/microglia markers and inflammatory cytokines, occurred in the nodose ganglion and hypothalamus of HFD-fed mice. A HFD blunted ghrelin signaling in the nodose ganglion via a mechanism involving in situ activation of inflammation. These results indicate that ghrelin resistance in the obese state may be caused by dysregulation of ghrelin signaling via the vagal afferent.

  8. Oxidative stress-induced CREB upregulation promotes DNA damage repair prior to neuronal cell death protection.

    PubMed

    Pregi, Nicolás; Belluscio, Laura María; Berardino, Bruno Gabriel; Castillo, Daniela Susana; Cánepa, Eduardo Tomás

    2017-01-01

    cAMP response element-binding (CREB) protein is a cellular transcription factor that mediates responses to different physiological and pathological signals. Using a model of human neuronal cells we demonstrate herein, that CREB is phosphorylated after oxidative stress induced by hydrogen peroxide. This phosphorylation is largely independent of PKA and of the canonical phosphoacceptor site at ser-133, and is accompanied by an upregulation of CREB expression at both mRNA and protein levels. In accordance with previous data, we show that CREB upregulation promotes cell survival and that its silencing results in an increment of apoptosis after oxidative stress. Interestingly, we also found that CREB promotes DNA repair after treatment with hydrogen peroxide. Using a cDNA microarray we found that CREB is responsible for the regulation of many genes involved in DNA repair and cell survival after oxidative injury. In summary, the neuroprotective effect mediated by CREB appears to follow three essential steps following oxidative injury. First, the upregulation of CREB expression that allows sufficient level of activated and phosphorylated protein is the primordial event that promotes the induction of genes of the DNA Damage Response. Then and when the DNA repair is effective, CREB induces detoxification and survival genes. This kinetics seems to be important to completely resolve oxidative-induced neuronal damages.

  9. Preventing diet-induced obesity in mice by adipose tissue transformation and angiogenesis using targeted nanoparticles

    PubMed Central

    Xue, Yuan; Xu, Xiaoyang; Zhang, Xue-Qing; Farokhzad, Omid C.; Langer, Robert

    2016-01-01

    The incidence of obesity, which is recognized by the American Medical Association as a disease, has nearly doubled since 1980, and obesity-related comorbidities have become a major threat to human health. Given that adipose tissue expansion and transformation require active growth of new blood vasculature, angiogenesis offers a potential target for the treatment of obesity-associated disorders. Here we construct two peptide-functionalized nanoparticle (NP) platforms to deliver either Peroxisome Proliferator-Activated Receptor gamma (PPARgamma) activator rosiglitazone (Rosi) or prostaglandin E2 analog (16,16-dimethyl PGE2) to adipose tissue vasculature. These NPs were engineered through self-assembly of a biodegradable triblock polymer composed of end-to-end linkages between poly(lactic-coglycolic acid)-b-poly(ethylene glycol) (PLGA-b-PEG) and an endothelial-targeted peptide. In this system, released Rosi promotes both transformation of white adipose tissue (WAT) into brown-like adipose tissue and angiogenesis, which facilitates the homing of targeted NPs to adipose angiogenic vessels, thereby amplifying their delivery. We show that i.v. administration of these NPs can target WAT vasculature, stimulate the angiogenesis that is required for the transformation of adipose tissue, and transform WAT into brown-like adipose tissue, by the up-regulation of angiogenesis and brown adipose tissue markers. In a diet-induced obese mouse model, these angiogenesis-targeted NPs have inhibited body weight gain and modulated several serological markers including cholesterol, triglyceride, and insulin, compared with the control group. These findings suggest that angiogenesis-targeting moieties with angiogenic stimulator-loaded NPs could be incorporated into effective therapeutic regimens for clinical treatment of obesity and other metabolic diseases. PMID:27140638

  10. Asb6 upregulation by Areca nut extracts is associated with betel quid-induced oral carcinogenesis.

    PubMed

    Hung, Kai-Feng; Lai, Kuo-Chu; Liu, Tsung-Yun; Liu, Chung-Ji; Lee, Te-Chang; Lo, Jeng-Fan

    2009-06-01

    Betel quit (BQ) chewing is a popular habit, especially in southern and southeastern Asia. Areca nut extracts (ANE), the major components of BQ, have been documented to induce reactive oxygen species, and consequently to cause genetic damage. ANE usage is tightly linked to oral cancer; however, the details of the molecular mechanism that results in carcinogenesis remain unclear. Previously, we successfully established HaCaT cells surviving from the long-term exposure of sublethal doses of ANE (Lai KC, Lee TC. Genetic damage in cultured human keratinocytes stressed by long-term exposure to areca nut extracts. Mutat Res 2006;599:66-75). Here, we identified the upregulation of Asb6, a coupling protein to the APS adapter protein, which is involved in insulin signaling for glucose transportation, of normal keratinocytes and oral cancer cells under ANE treatment. Immunohistochemical analyses of Asb6 on oral squamous cell carcinoma (OSCC) tissues (n=57) demonstrated the positive correlation between Asb6 upregulation (cancerous tissues versus adjacent normal tissues) and clinicopathological features. We showed that the combination of ANE-enhanced Asb6 expression in vitro and Asb6 upregulation in OSCC patients leads to poor survival status. In conclusion, our results suggest that upregulated Asb6 could act as a prognostic marker for oral cancer.

  11. Oleic/Palmitate Induces Apoptosis in Human Articular Chondrocytes via Upregulation of NOX4 Expression and ROS Production.

    PubMed

    Fu, Dapeng; Lu, Jianmin; Yang, Sheng

    2016-07-01

    The association between obesity and reactive oxygen species (ROS) production in osteoarthritis (OA) patients has already been identified. However, the specific mechanism underlying ROS production and OA progression has never been elucidated. Osteoarthritic cartilage was obtained from patients undergoing total hip arthroplasty, and chondrocytes were isolated from these tissues. The cells were treated with varying concentrations (10,100,500 μM, and 5 mM) of oleic/palmitate (O/P) mixture at different times, that is at 6, 24, and 48 h. Cell viability was determined using MTT assay. ROS production was detected using immunofluorescence and flow cytometry. The protein levels of NOX4 and cleaved-caspase3 were detected using Western blot assay. O/P significantly decreased cell viability at 10, 100, 500 μM, and 5 mM in a dose-dependent manner. Furthermore, the cell viability was reduced by 500 μM O/P mixture at 6, 24, and 48 h in a time-dependent manner. Pretreatment with 500 μM O/P significantly enhanced ROS production and cell apoptosis in chondrocytes. Furthermore, treatment with O/P mixture significantly enhanced the expression of NOX4 and caspase3 activation in a dose- and time- dependent manner. More importantly, inhibition of NOX4 could partially eliminate O/P-induced chondrocytes apoptosis by reducing ROS production. To conclude, O/P treatment enhances ROS production and cell apoptosis mainly by upregulating the protein levels of NOX4 and caspase3 activation in chondrocytes, indicating a potential therapeutic target of OA in obesity patients.

  12. Doxorubicin induces cardiotoxicity through upregulation of death receptors mediated apoptosis in cardiomyocytes

    PubMed Central

    Zhao, Liqun; Zhang, Baolin

    2017-01-01

    Doxorubicin is a highly effective anticancer agent but causes cardiotoxicity in many patients. The mechanisms of doxorubicin-induced cardiotoxicity remain incompletely understood. Here we investigated doxorubicin-induced cytotoxicity in human induced pluripotent stem cells-derived cardiomyocytes (iPS-CMs). We found that doxorubicin and related anthracycline agents (e.g., daunorubicin, idarubicin, and epirubicin) significantly upregulated the expression of death receptors (DRs) (TNFR1, Fas, DR4 and DR5) in iPS-derived cardiomyocytes at both protein and mRNA levels. The resulting iPS-CMs cells underwent spontaneous apoptosis which was further enhanced by physiologically relevant death ligands including TNF-related apoptosis inducing ligand (TRAIL). Furthermore, TRAIL potentiated doxorubicin-induced decrease in beating rate and amplitude of iPS-derived cardiomyocytes. These data demonstrate that the induction of death receptors in cardiomyocytes is likely a critical mechanism by which doxorubicin causes cardiotoxicity. PMID:28300219

  13. Mechanism of the neuroleptic-induced obesity in female rats.

    PubMed

    Baptista, T; Contreras, Q; Teneud, L; Albornoz, M A; Acosta, A; Páez, X; de Quijada, M; LaCruz, A; Hernández, L

    1998-01-01

    1. Obesity is an undesirable side effect of neuroleptics which affects 50% approximately of patients under a program of chronic administration. 2. An animal model of neuroleptic-induced obesity and hyperphagia has been developed in female rats treated chronically with sulpiride (20 mg/Kg/ip. for 21 days). However, it is unknown whether or not the hyperphagia is essential for the development of this type of obesity. 3. Sulpiride or vehicle was administered in two experimental conditions: in the first one, food was available in an amount which was three times the previous individual daily food intake; in the second one, the daily food provision was maintained at the individual daily average before starting the treatments. This way hyperphagia was prevented in half of the groups. Besides the body weight gain measurement in all the groups, the serum levels of estradiol, prolactin, glucose and lipids were assessed in the groups with unrestricted food intake. 4. Food restriction prevented the sulpiride-induced weight gain, even though the rats displayed a permanent diestrus which suggests an hyperprolactinemia-induced impairment in the balance of the reproductive hormones that may promote weight gain. However, the basal levels of estradiol were not affected by sulpiride. 5. The high density cholesterol was significantly increased by sulpiride, and the serum glucose levels were significantly decreased, however these changes were only detected during the first week of treatment. 6. The decrease in the serum glucose levels may be an early consequence of hyperinsulinemia. 7. Neuroleptic-induced obesity in rats appears to mimic energy intake, endocrine status and carbohydrate metabolism in humans under chronic neuroleptic administration. However, these rodents did not display the typical changes in blood lipids observed in human obesity.

  14. Increased antigen presentation but impaired T cells priming after upregulation of interferon-beta induced by lipopolysaccharides is mediated by upregulation of B7H1 and GITRL.

    PubMed

    Wang, Fang; Wang, Yan Yan; Li, Juan; You, Xiang; Qiu, Xin Hui; Wang, Yi Nan; Gao, Feng Guang

    2014-01-01

    Dendritic cells are able to present Ag-derived peptides on MHC class I and II molecules and induce T cells priming. Lipopolysaccharides (LPS), an activator of Toll-like 4 receptor (TLR4) signaling, has been demonstrated to facilitate Ag-presentation, up-regulate surface molecules expression but impair T cells priming. In this study, we investigated the effect of LPS on nicotine-enhanced DCs-dependent T cells priming and the mechanisms of LPS orchestrating the immunosuppressive program. We could demonstrate that the treatment with LPS resulted in increased surface molecules expression, enhanced Ag-presentation, up-regulated release of TGF-beta, TNF-alpha, IL-6, and IFN-beta. Concomititantly, the upregulation of IFN-beta in DCs induces the up-regulation of coinhibitory molecules B7H1 and GITRL, which cause an impaired activation of naïve Ag-specific T cells and the induction of T cell tolerance by enhancing B7H1-PD-1 interactions and promoting GITRL-GITL facilitated Treg generation, respectively. These data provide a mechanistic basis for the immunomodulatory action of IFN-beta which might open new possibilities in the development of therapeutic approaches aimed at the control of excessive immune response and persistent infection.

  15. Magnolia Extract (BL153) Ameliorates Kidney Damage in a High Fat Diet-Induced Obesity Mouse Model

    PubMed Central

    Cui, Wenpeng; Wang, Yangwei; Chen, Qiang; Sun, Weixia; Cai, Lu; Tan, Yi; Kim, Ki-Soo; Kim, Ki Ho; Kim, Young Heui

    2013-01-01

    Accumulating evidence demonstrated that obesity is a risk factor for renal structural and functional changes, leading to the end-stage renal disease which imposes a heavy economic burden on the community. However, no effective therapeutic method for obesity-associated kidney disease is available. In the present study, we explored the therapeutic potential of a magnolia extract (BL153) for treating obesity-associated kidney damage in a high fat diet- (HFD-) induced mouse model. The results showed that inflammation markers (tumor necrosis factor-α and plasminogen activator inhibitor-1) and oxidative stress markers (3-nitrotyrosine and 4-hydroxy-2-nonenal) were all significantly increased in the kidney of HFD-fed mice compared to mice fed with a low fat diet (LFD). Additionally, proteinuria and renal structure changes in HFD-fed mice were much more severe than that in LFD-fed mice. However, all these alterations were attenuated by BL153 treatment, accompanied by upregulation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and hexokinase II (HK II) expression in the kidney. The present study indicates that BL153 administration may be a novel approach for renoprotection in obese individuals by antiinflammation and anti-oxidative stress most likely via upregulation of PGC-1α and HK II signal in the kidney. PMID:24381715

  16. Ferulic acid improves lipid and glucose homeostasis in high-fat diet-induced obese mice.

    PubMed

    Naowaboot, Jarinyaporn; Piyabhan, Pritsana; Munkong, Narongsuk; Parklak, Wason; Pannangpetch, Patchareewan

    2016-02-01

    Ferulic acid (FA) is a plant phenolic acid that has several pharmacological effects including antihyperglycaemic activity. Thus, the objective of this study is to investigate the effect of FA on glucose and lipid metabolism in high-fat diet (HFD)-induced obese mice. Institute for Cancer Research (ICR) mice were fed a HFD (45 kcal% fat) for 16 weeks. At the ninth week of induction, the obese mice were orally administered with daily FA doses of 25 and 50 mg/kg for the next eight weeks. The results show that FA significantly reduced the elevated blood glucose and serum leptin levels, lowered the insulin resistance, and increased the serum adiponectin level. Moreover, serum lipid level, and liver cholesterol and triglyceride accumulations were also reduced. The histological examination showed clear evidence of a decrease in the lipid droplets in liver tissues and smaller size of fat cells in the adipose tissue in the obese mice treated with FA. Interestingly, FA reduced the expression of hepatic lipogenic genes such as sterol regulatory element-binding protein 1c (SREBP1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC). It could also up-regulate hepatic carnitine palmitoyltransferase 1a (CPT1a) gene and peroxisome proliferator-activated receptor alpha (PPARα) proteins. The FA treatment was also found to suppress the protein expressions of hepatic gluconeogenic enzymes, phosphoenolpyruvate carboxylase (PEPCK) and glucose-6-phosphatase (G6Pase). In conclusion, the findings of this study demonstrate that FA improves the glucose and lipid homeostasis in HFD-induced obese mice probably via modulating the expression of lipogenic and gluconeogenic genes in liver tissues.

  17. Dux4 induces cell cycle arrest at G1 phase through upregulation of p21 expression

    SciTech Connect

    Xu, Hongliang; Wang, Zhaoxia; Jin, Suqin; Hao, Hongjun; Zheng, Lemin; Zhou, Boda; Zhang, Wei; Lv, He; Yuan, Yun

    2014-03-28

    Highlights: • Dux4 induced TE671 cell proliferation defect and G1 phase arrest. • Dux4 upregulated p21 expression without activating p53. • Silencing p21 rescued Dux4 mediated proliferation defect and cell cycle arrest. • Sp1 binding site was required for Dux4-induced p21 promoter activation. - Abstract: It has been implicated that Dux4 plays crucial roles in development of facioscapulohumeral dystrophy. But the underlying myopathic mechanisms and related down-stream events of this retrogene were far from clear. Here, we reported that overexpression of Dux4 in a cell model TE671 reduced cell proliferation rate, and increased G1 phase accumulation. We also determined the impact of Dux4 on p53/p21 signal pathway, which controls the checkpoint in cell cycle progression. Overexpression of Dux4 increased p21 mRNA and protein level, while expression of p53, phospho-p53 remained unchanged. Silencing p21 rescued Dux4 mediated proliferation defect and cell cycle arrest. Furthermore, we demonstrated that enhanced Dux4 expression increased p21 promoter activity and elevated expression of Sp1 transcription factor. Mutation of Sp1 binding site decreased dux4 induced p21 promoter activation. Chromatin immunoprecipitation (ChIP) assays confirmed the Dux4-induced binding of Sp1 to p21 promoter in vivo. These results suggest that Dux4 might induce proliferation inhibition and G1 phase arrest through upregulation of p21.

  18. Murine Hepatic miRNAs Expression and Regulation of Gene Expression in Diet-Induced Obese Mice

    PubMed Central

    Park, Jae-Ho; Ahn, Jiyun; Kim, Suna; Kwon, Dae Young; Ha, Tae Youl

    2011-01-01

    MicroRNAs are short, non-coding RNA molecules that regulate gene expression primarily by translational repression or by messenger RNA degradation. MicroRNAs play crucial roles in various biological processes. However, little is known regarding their role in obesity. We investigated differences of microRNA (miRNA) expression in liver tissue from diet-induced obese mice and potential effects of them on gene and protein expression. We used a miRNA microarray and quantitative RT-PCR to determine miRNA expression in murine liver tissue. Gene and protein expression were determined by qRT-PCR and Western blot analysis. Effects of miRNA by knock-down using RNAi or overexpression on putative target genes and/or proteins in a murine hepatic cell line were also investigated. MicroRNA array and qRT-PCR analsysis revealed that > 50 miRNAs were down- or upregulated more than 2-fold in the liver of diet-induced obese mice. While changes in expression of many genes were observed at the mRNA level, some were only altered at the protein level. Overexpression or knock-down of miR-107 in murine hepatic cells revealed that the expression of its putative target, fatty acid synthase, was dramatically decreased or increased, respectively. In conclusion, more than 50 hepatic miRNAs were dysregulated in diet-induced obese mice. Some of them regulate protein expression at translation level and others regulate mRNA expression at transcriptional level. MiR-107 is downregulated while FASN, a putative target of miR-107, was increased in diet-induced obese mice. These findings provide the evidence of the correlation of miRNAs and their targets in diet-induced obese mice. PMID:21120623

  19. Preconditioning-induced CXCL12 upregulation minimizes leukocyte infiltration after stroke in ischemia-tolerant mice.

    PubMed

    Selvaraj, Uma Maheswari; Ortega, Sterling B; Hu, Ruilong; Gilchrist, Robert; Kong, Xiangmei; Partin, Alexander; Plautz, Erik J; Klein, Robyn S; Gidday, Jeffrey M; Stowe, Ann M

    2017-03-01

    Repetitive hypoxic preconditioning creates long-lasting, endogenous protection in a mouse model of stroke, characterized by reductions in leukocyte-endothelial adherence, inflammation, and infarct volumes. The constitutively expressed chemokine CXCL12 can be upregulated by hypoxia and limits leukocyte entry into brain parenchyma during central nervous system inflammatory autoimmune disease. We therefore hypothesized that the sustained tolerance to stroke induced by repetitive hypoxic preconditioning is mediated, in part, by long-term CXCL12 upregulation at the blood-brain barrier (BBB). In male Swiss Webster mice, repetitive hypoxic preconditioning elevated cortical CXCL12 protein levels, and the number of cortical CXCL12+ microvessels, for at least two weeks after the last hypoxic exposure. Repetitive hypoxic preconditioning-treated mice maintained more CXCL12-positive vessels than untreated controls following transient focal stroke, despite cortical decreases in CXCL12 mRNA and protein. Continuous administration of the CXCL12 receptor (CXCR4) antagonist AMD3100 for two weeks following repetitive hypoxic preconditioning countered the increase in CXCL12-positive microvessels, both prior to and following stroke. AMD3100 blocked the protective post-stroke reductions in leukocyte diapedesis, including macrophages and NK cells, and blocked the protective effect of repetitive hypoxic preconditioning on lesion volume, but had no effect on blood-brain barrier dysfunction. These data suggest that CXCL12 upregulation prior to stroke onset, and its actions following stroke, contribute to the endogenous, anti-inflammatory phenotype induced by repetitive hypoxic preconditioning.

  20. Amelioration of estrogen deficiency-induced obesity by collagen hydrolysate

    PubMed Central

    Chiang, Tsay-I; Chang, I-Chang; Lee, Hsueh-Hui; Hsieh, Kuang hui; Chiu, Yung-Wei; Lai, Te-Jen; Liu, Jer-Yuh; Hsu, Li-Sung; Kao, Shao-Hsuan

    2016-01-01

    Objectives: Menopausal transition with declining estrogen levels significantly affects the physiological properties of women and consequently contributes to a series of medical conditions, including obesity. Obesity is a crucial risk factor associated with cardiovascular diseases, diabetes mellitus, and breast cancer. Increasing dietary protein content improves satiety and energy expenditure. Thus, we hypothesize that supplementing with collagen, a common dietary protein, may alleviate menopause-induced obesity. Methods: We used ovariectomized (OVX) rats to mimic a menopausal human. The body weight of OVX rats significantly increased compared with that of sham-operated rats (P<0.05), but uterus weight was decreased. Adipocyte size in perigonadal adipose tissue also increased (P<0.05). Results: By contrast, OVX rats supplemented with aqueous collagen hydrolysate (2.5 mg/mL) exhibited significant attenuation in body weight gain and adipocyte enlargement (P<0.05), but insignificant change in uterus weight. Further investigation indicated that collagen hydrolysate supplementation insignificantly affected the levels of dorsal fat, serum total cholesterol, and serum triacylglycerol. Levels of serum biochemical factors, calcium, phosphorus, and glucose were also insignificantly altered by collagen hydrolysate supplementation. Conclusion: Collagen hydrolysate supplementation reduced body weight gain and adipocyte enlargement in response to ovariectomy but slightly affected blood lipids, calcium, and glucose in both sham-operated and OVX rats. Collagen hydrolysate supplementation is beneficial in ameliorating estrogen deficiency-induced obesity and its associated risk factors. PMID:27877077

  1. Amelioration of estrogen deficiency-induced obesity by collagen hydrolysate.

    PubMed

    Chiang, Tsay-I; Chang, I-Chang; Lee, Hsueh-Hui; Hsieh, Kuang Hui; Chiu, Yung-Wei; Lai, Te-Jen; Liu, Jer-Yuh; Hsu, Li-Sung; Kao, Shao-Hsuan

    2016-01-01

    Objectives: Menopausal transition with declining estrogen levels significantly affects the physiological properties of women and consequently contributes to a series of medical conditions, including obesity. Obesity is a crucial risk factor associated with cardiovascular diseases, diabetes mellitus, and breast cancer. Increasing dietary protein content improves satiety and energy expenditure. Thus, we hypothesize that supplementing with collagen, a common dietary protein, may alleviate menopause-induced obesity. Methods: We used ovariectomized (OVX) rats to mimic a menopausal human. The body weight of OVX rats significantly increased compared with that of sham-operated rats (P<0.05), but uterus weight was decreased. Adipocyte size in perigonadal adipose tissue also increased (P<0.05). Results: By contrast, OVX rats supplemented with aqueous collagen hydrolysate (2.5 mg/mL) exhibited significant attenuation in body weight gain and adipocyte enlargement (P<0.05), but insignificant change in uterus weight. Further investigation indicated that collagen hydrolysate supplementation insignificantly affected the levels of dorsal fat, serum total cholesterol, and serum triacylglycerol. Levels of serum biochemical factors, calcium, phosphorus, and glucose were also insignificantly altered by collagen hydrolysate supplementation. Conclusion: Collagen hydrolysate supplementation reduced body weight gain and adipocyte enlargement in response to ovariectomy but slightly affected blood lipids, calcium, and glucose in both sham-operated and OVX rats. Collagen hydrolysate supplementation is beneficial in ameliorating estrogen deficiency-induced obesity and its associated risk factors.

  2. Upregulation of FOXM1 induces genomic instability in human epidermal keratinocytes

    PubMed Central

    2010-01-01

    Background The human cell cycle transcription factor FOXM1 is known to play a key role in regulating timely mitotic progression and accurate chromosomal segregation during cell division. Deregulation of FOXM1 has been linked to a majority of human cancers. We previously showed that FOXM1 was upregulated in basal cell carcinoma and recently reported that upregulation of FOXM1 precedes malignancy in a number of solid human cancer types including oral, oesophagus, lung, breast, kidney, bladder and uterus. This indicates that upregulation of FOXM1 may be an early molecular signal required for aberrant cell cycle and cancer initiation. Results The present study investigated the putative early mechanism of UVB and FOXM1 in skin cancer initiation. We have demonstrated that UVB dose-dependently increased FOXM1 protein levels through protein stabilisation and accumulation rather than de novo mRNA expression in human epidermal keratinocytes. FOXM1 upregulation in primary human keratinocytes triggered pro-apoptotic/DNA-damage checkpoint response genes such as p21, p38 MAPK, p53 and PARP, however, without causing significant cell cycle arrest or cell death. Using a high-resolution Affymetrix genome-wide single nucleotide polymorphism (SNP) mapping technique, we provided the evidence that FOXM1 upregulation in epidermal keratinocytes is sufficient to induce genomic instability, in the form of loss of heterozygosity (LOH) and copy number variations (CNV). FOXM1-induced genomic instability was significantly enhanced and accumulated with increasing cell passage and this instability was increased even further upon exposure to UVB resulting in whole chromosomal gain (7p21.3-7q36.3) and segmental LOH (6q25.1-6q25.3). Conclusion We hypothesise that prolonged and repeated UVB exposure selects for skin cells bearing stable FOXM1 protein causes aberrant cell cycle checkpoint thereby allowing ectopic cell cycle entry and subsequent genomic instability. The aberrant upregulation of FOXM1

  3. Catalase activity prevents exercise-induced up-regulation of vasoprotective proteins in venous tissue.

    PubMed

    Dao, Vu Thao-Vi; Floeren, Melanie; Kumpf, Stephanie; Both, Charlotte; Peter, Bärbel; Balz, Vera; Suvorava, Tatsiana; Kojda, Georg

    2011-11-01

    Physical activity induces favourable changes of arterial gene expression and protein activity, although little is known about its effect in venous tissue. Although our understanding of the initiating molecular signals is still incomplete, increased expression of endothelial nitric oxide synthase (eNOS) is considered a key event. This study sought to investigate the effects of two different training protocols on the expression of eNOS and extracellular superoxide dismutase (ecSOD) in venous and lung tissue and to evaluate the underlying molecular mechanisms. C57Bl/6 mice underwent voluntary exercise or forced physical activity. Changes of vascular mRNA and protein levels and activity of eNOS, ecSOD and catalase were determined in aorta, heart, lung and vena cava. Both training protocols similarly increased relative heart weight and resulted in up-regulation of aortic and myocardial eNOS. In striking contrast, eNOS expression in vena cava and lung remained unchanged. Likewise, exercise up-regulated ecSOD in the aorta and in left ventricular tissue but remained unchanged in lung tissue. Catalase expression in lung tissue and vena cava of exercised mice exceeded that in aorta by 6.9- and 10-fold, respectively, suggesting a lack of stimulatory effects of hydrogen peroxide. In accordance, treatment of mice with the catalase inhibitor aminotriazole for 6 weeks resulted in significant up-regulation of eNOS and ecSOD in vena cava. These data suggest that physiological venous catalase activity prevents exercise-induced up-regulation of eNOS and ecSOD. Furthermore, therapeutic inhibition of vascular catalase might improve pulmonary rehabilitation.

  4. PTEN induces apoptosis and cavitation via HIF-2-dependent Bnip3 upregulation during epithelial lumen formation

    PubMed Central

    Qi, Y; Liu, J; Saadat, S; Tian, X; Han, Y; Fong, G-H; Pandolfi, P P; Lee, L Y; Li, S

    2015-01-01

    The tumor suppressor phosphatase and tensin homolog (PTEN) dephosphorylates PIP3 and antagonizes the prosurvival PI3K-Akt pathway. Targeted deletion of PTEN in mice led to early embryonic lethality. To elucidate its role in embryonic epithelial morphogenesis and the underlying mechanisms, we used embryonic stem cell-derived embryoid body (EB), an epithelial cyst structurally similar to the periimplantation embryo. PTEN is upregulated during EB morphogenesis in parallel with apoptosis of core cells, which mediates EB cavitation. Genetic ablation of PTEN causes Akt overactivation, apoptosis resistance and cavitation blockade. However, rescue experiments using mutant PTEN and pharmacological inhibition of Akt suggest that the phosphatase activity of PTEN and Akt are not involved in apoptosis-mediated cavitation. Instead, hypoxia-induced upregulation of Bnip3, a proapoptotic BH3-only protein, mediates PTEN-dependent apoptosis and cavitation. PTEN inactivation inhibits hypoxia- and reactive oxygen species-induced Bnip3 elevation. Overexpression of Bnip3 in PTEN-null EBs rescues apoptosis of the core cells. Mechanistically, suppression of Bnip3 following PTEN loss is likely due to reduction of hypoxia-inducible factor-2α (HIF-2α) because forced expression of an oxygen-stable HIF-2α mutant rescues Bnip3 expression and apoptosis. Lastly, we show that HIF-2α is upregulated by PTEN at both transcriptional and posttranscriptional levels. Ablation of prolyl hydroxylase domain-containing protein 2 (PHD2) in normal EBs or inhibition of PHD activities in PTEN-null EBs stabilizes HIF-2α and induces Bnip3 and caspase-3 activation. Altogether, these results suggest that PTEN is required for apoptosis-mediated cavitation during epithelial morphogenesis by regulating the expression of HIF-2α and Bnip3. PMID:25394489

  5. Histone Hyperacetylation Up-regulates Protein Kinase Cδ in Dopaminergic Neurons to Induce Cell Death

    PubMed Central

    Jin, Huajun; Kanthasamy, Arthi; Harischandra, Dilshan S.; Kondru, Naveen; Ghosh, Anamitra; Panicker, Nikhil; Anantharam, Vellareddy; Rana, Ajay; Kanthasamy, Anumantha G.

    2014-01-01

    The oxidative stress-sensitive protein kinase Cδ (PKCδ) has been implicated in dopaminergic neuronal cell death. However, little is known about the epigenetic mechanisms regulating PKCδ expression in neurons. Here, we report a novel mechanism by which the PKCδ gene can be regulated by histone acetylation. Treatment with histone deacetylase (HDAC) inhibitor sodium butyrate (NaBu) induced PKCδ expression in cultured neurons, brain slices, and animal models. Several other HDAC inhibitors also mimicked NaBu. The chromatin immunoprecipitation analysis revealed that hyperacetylation of histone H4 by NaBu is associated with the PKCδ promoter. Deletion analysis of the PKCδ promoter mapped the NaBu-responsive element to an 81-bp minimal promoter region. Detailed mutagenesis studies within this region revealed that four GC boxes conferred hyperacetylation-induced PKCδ promoter activation. Cotransfection experiments and Sp inhibitor studies demonstrated that Sp1, Sp3, and Sp4 regulated NaBu-induced PKCδ up-regulation. However, NaBu did not alter the DNA binding activities of Sp proteins or their expression. Interestingly, a one-hybrid analysis revealed that NaBu enhanced transcriptional activity of Sp1/Sp3. Overexpression of the p300/cAMP-response element-binding protein-binding protein (CBP) potentiated the NaBu-mediated transactivation potential of Sp1/Sp3, but expressing several HDACs attenuated this effect, suggesting that p300/CBP and HDACs act as coactivators or corepressors in histone acetylation-induced PKCδ up-regulation. Finally, using genetic and pharmacological approaches, we showed that NaBu up-regulation of PKCδ sensitizes neurons to cell death in a human dopaminergic cell model and brain slice cultures. Together, these results indicate that histone acetylation regulates PKCδ expression to augment nigrostriatal dopaminergic cell death, which could contribute to the progressive neuropathogenesis of Parkinson disease. PMID:25342743

  6. Neuropeptide Y in normal eating and in genetic and dietary-induced obesity

    PubMed Central

    Beck, B

    2006-01-01

    overactive NPY system (increased mRNA expression in the ARC associated with an upregulation of the receptors) is characteristic of rats or rodent strains sensitive to dietary-induced obesity. Finally, NPY appears to play an important role in body weight and feeding regulation, and while it does not constitute the only target for drug treatment of obesity, it may nevertheless provide a useful target in conjunction with others. PMID:16874931

  7. FOXO3-mediated up-regulation of Bim contributes to rhein-induced cancer cell apoptosis.

    PubMed

    Wang, Jiao; Liu, Shu; Yin, Yancun; Li, Mingjin; Wang, Bo; Yang, Li; Jiang, Yangfu

    2015-03-01

    The anthraquinone compound rhein is a natural agent in the traditional Chinese medicine rhubarb. Preclinical studies demonstrate that rhein has anticancer activity. Treatment of a variety of cancer cells with rhein may induce apoptosis. Here, we report that rhein induces atypical unfolded protein response in breast cancer MCF-7 cells and hepatoma HepG2 cells. Rhein induces CHOP expression, eIF2α phosphorylation and caspase cleavage, while it does not induce glucose-regulated protein 78 (GRP78) expression in both MCF-7 and HepG2 cells. Meanwhile, rhein inhibits thapsigargin-induced GRP78 expression and X box-binding protein 1 splicing. In addition, rhein inhibits Akt phosphorylation and stimulates FOXO transactivation activity. Rhein induces Bim expression in MCF-7 and HepG2 cells, which can be abrogated by FOXO3a knockdown. Knockdown of FOXO3a or Bim abrogates rhein-induced caspase cleavage and apoptosis. The chemical chaperone 4-phenylbutyrate acid antagonizes the induction of FOXO activation, Bim expression and caspase cleavage by rhein, indicating that protein misfolding may be involved in triggering these deleterious effects. We conclude that FOXO3a-mediated up-regulation of Bim is a key mechanism underlying rhein-induced cancer cells apoptosis.

  8. CARD9 knockout ameliorates myocardial dysfunction associated with high fat diet-induced obesity.

    PubMed

    Cao, Li; Qin, Xing; Peterson, Matthew R; Haller, Samantha E; Wilson, Kayla A; Hu, Nan; Lin, Xin; Nair, Sreejayan; Ren, Jun; He, Guanglong

    2016-03-01

    Obesity is associated with chronic inflammation which plays a critical role in the development of cardiovascular dysfunction. Because the adaptor protein caspase recruitment domain-containing protein 9 (CARD9) in macrophages regulates innate immune responses via activation of pro-inflammatory cytokines, we hypothesize that CARD9 mediates the pro-inflammatory signaling associated with obesity en route to myocardial dysfunction. C57BL/6 wild-type (WT) and CARD9(-/-) mice were fed normal diet (ND, 12% fat) or a high fat diet (HFD, 45% fat) for 5months. At the end of 5-month HFD feeding, cardiac function was evaluated using echocardiography. Cardiomyocytes were isolated and contractile properties were measured. Immunofluorescence was performed to detect macrophage infiltration in the heart. Heart tissue homogenates, plasma, and supernatants from isolated macrophages were collected to measure the concentrations of pro-inflammatory cytokines using ELISA kits. Western immunoblotting analyses were performed on heart tissue homogenates and isolated macrophages to explore the underlying signaling mechanism(s). CARD9 knockout alleviated HFD-induced insulin resistance and glucose intolerance, prevented myocardial dysfunction with preserved cardiac fractional shortening and cardiomyocyte contractile properties. CARD9 knockout also significantly decreased the number of infiltrated macrophages in the heart with reduced myocardium-, plasma-, and macrophage-derived cytokines including IL-6, IL-1β and TNFα. Finally, CARD9 knockout abrogated the increase of p38 MAPK phosphorylation, the decrease of LC3BII/LC3BI ratio and the up-regulation of p62 expression in the heart induced by HFD feeding and restored cardiac autophagy signaling. In conclusion, CARD9 knockout ameliorates myocardial dysfunction associated with HFD-induced obesity, potentially through reduction of macrophage infiltration, suppression of p38 MAPK phosphorylation, and preservation of autophagy in the heart.

  9. RMI1 deficiency in mice protects from diet and genetic-induced obesity.

    PubMed

    Suwa, Akira; Yoshino, Masayasu; Yamazaki, Chihiro; Naitou, Masanori; Fujikawa, Rie; Matsumoto, Shun-Ichiro; Kurama, Takeshi; Shimokawa, Teruhiko; Aramori, Ichiro

    2010-02-01

    The aim of this study is to discover and characterize novel energy homeostasis-related molecules. We screened stock mouse embryonic stem cells established using the exchangeable gene trap method, and examined the effects of deficiency of the target gene on diet and genetic-induced obesity. The mutant strain 0283, which has an insertion at the recQ-mediated genome instability 1 (RMI1) locus, possesses a number of striking features that allow it to resist metabolic abnormalities. Reduced RMI1 expression, lower fasting-blood glucose and a reduced body weight (normal diet) were observed in the mutant mice. When fed a high-fat diet, the mutant mice were resistant to obesity, and also showed improved glucose intolerance and reduced abdominal fat tissue mass and food intake. In addition, the mutants were also resistant to obesity induced by the lethal yellow agouti (A(y)) gene. Endogenous RMI1 genes were found to be up-regulated in the liver and adipose tissue of KK-A(y) mice. RMI1 is a component of the Bloom's syndrome gene helicase complex that maintains genome integrity and activates cell-cycle checkpoint machinery. Interestingly, diet-induced expression of E2F8 mRNA, which is an important cell cycle-related molecule, was suppressed in the mutant mice. These results suggest that the regulation of energy balance by RMI1 is attributable to the regulation of food intake and E2F8 expression in adipose tissue. Taken together, these findings demonstrate that RMI1 is a novel molecule that regulates energy homeostasis.

  10. Upregulation of SK3 and IK1 Channels Contributes to the Enhanced Endothelial Calcium Signaling and the Preserved Coronary Relaxation in Obese Zucker Rats

    PubMed Central

    Climent, Belén; Moreno, Laura; Martínez, Pilar; Contreras, Cristina; Sánchez, Ana; Pérez-Vizcaíno, Francisco; García-Sacristán, Albino; Rivera, Luis; Prieto, Dolores

    2014-01-01

    Background and Aims Endothelial small- and intermediate-conductance KCa channels, SK3 and IK1, are key mediators in the endothelium-derived hyperpolarization and relaxation of vascular smooth muscle and also in the modulation of endothelial Ca2+ signaling and nitric oxide (NO) release. Obesity is associated with endothelial dysfunction and impaired relaxation, although how obesity influences endothelial SK3/IK1 function is unclear. Therefore we assessed whether the role of these channels in the coronary circulation is altered in obese animals. Methods and Results In coronary arteries mounted in microvascular myographs, selective blockade of SK3/IK1 channels unmasked an increased contribution of these channels to the ACh- and to the exogenous NO- induced relaxations in arteries of Obese Zucker Rats (OZR) compared to Lean Zucker Rats (LZR). Relaxant responses induced by the SK3/IK1 channel activator NS309 were enhanced in OZR and NO- endothelium-dependent in LZR, whereas an additional endothelium-independent relaxant component was found in OZR. Fura2-AM fluorescence revealed a larger ACh-induced intracellular Ca2+ mobilization in the endothelium of coronary arteries from OZR, which was inhibited by blockade of SK3/IK1 channels in both LZR and OZR. Western blot analysis showed an increased expression of SK3/IK1 channels in coronary arteries of OZR and immunohistochemistry suggested that it takes place predominantly in the endothelial layer. Conclusions Obesity may induce activation of adaptive vascular mechanisms to preserve the dilator function in coronary arteries. Increased function and expression of SK3/IK1 channels by influencing endothelial Ca2+ dynamics might contribute to the unaltered endothelium-dependent coronary relaxation in the early stages of obesity. PMID:25302606

  11. Regulation of Actinomycin D induced upregulation of Mdm2 in H1299 cells.

    PubMed

    Li, Lianjie; Cui, Di; Zheng, Shijun J; Lou, Huiqiang; Tang, Jun

    2012-02-01

    Mdm2 is a critical negative regulator of the p53 tumor suppressor and also has many p53-independent functions. Deregulation of Mdm2 is closely associated with tumorigenesis. However, how Mdm2 is regulated in response to various stresses is not well understood. In this study, we found that Mdm2 was stabilized and upregulated upon Actinomycin D (ActD) treatment in the p53-deficient H1299 cell line. This Mdm2 upregulation was not dependent on the ribosomal protein L11, an essential player in ribosomal stress-induced p53 activation, but did require a NEDDylation-dependent mechanism. We further demonstrated that the ActD-induced Mdm2 stabilization may be modulated by the cell growth signaling, and that knockdown of Mdm2 enhanced ActD-induced cell death in H1299 cells. These results suggested a role of Mdm2 in the ribosomal stress response in the p53 deficient cells, which could be exploited in therapeutic use for treating cancers harboring p53 mutations.

  12. DJ-1 contributes to adipogenesis and obesity-induced inflammation

    PubMed Central

    Kim, Jung-Min; Jang, Hyun-Jun; Choi, Soo Youn; Park, Soo-Ah; Kim, Il Shin; Yang, Yong Ryoul; Lee, Yong Hwa; Ryu, Sung Ho; Suh, Pann-Ghill

    2014-01-01

    Adipose tissue functions as an endocrine organ, and the development of systemic inflammation in adipose tissue is closely associated with metabolic diseases, such as obesity and insulin resistance. Accordingly, the fine regulation of the inflammatory response caused by obesity has therapeutic potential for the treatment of metabolic syndrome. In this study, we analyzed the role of DJ-1 (PARK7) in adipogenesis and inflammation related to obesity in vitro and in vivo. Many intracellular functions of DJ-1, including oxidative stress regulation, are known. However, the possibility of DJ-1 involvement in metabolic disease is largely unknown. Our results suggest that DJ-1 deficiency results in reduced adipogenesis and the down-regulation of pro-inflammatory cytokines in vitro. Furthermore, DJ-1-deficient mice show a low-level inflammatory response in the high-fat diet-induced obesity model. These results indicate previously unknown functions of DJ-1 in metabolism and therefore suggest that precise regulation of DJ-1 in adipose tissue might have a therapeutic advantage for metabolic disease treatment. PMID:24925581

  13. Eurycomanone induce apoptosis in HepG2 cells via up-regulation of p53

    PubMed Central

    Zakaria, Yusmazura; Rahmat, Asmah; Pihie, Azimahtol Hawariah Lope; Abdullah, Noor Rain; Houghton, Peter J

    2009-01-01

    Background Eurycomanone is a cytotoxic compound found in Eurycoma longifolia Jack. Previous studies had noted the cytotoxic effect against various cancer cell lines. The aim of this study is to investigate the cytotoxicity against human hepato carcinoma cell in vitro and the mode of action. The cytotoxicity of eurycomanone was evaluated using MTT assay and the mode of cell death was detected by Hoechst 33258 nuclear staining and flow cytometry with Annexin-V/propidium iodide double staining. The protein expression Bax, Bcl-2, p53 and cytochrome C were studied by flow cytometry using a spesific antibody conjugated fluorescent dye to confirm the up-regulation of p53 and Bax in cancer cells. Results The findings suggested that eurycomanone was cytotoxic on cancerous liver cell, HepG2 and less toxic on normal cells Chang's liver and WLR-68. Furthermore, various methods proved that apoptosis was the mode of death in eurycomanone-treated HepG2 cells. The characteristics of apoptosis including chromatin condensation, DNA fragmentation and apoptotic bodies were found following eurycomanone treatment. This study also found that apoptotic process triggered by eurycomanone involved the up-regulation of p53 tumor suppressor protein. The up-regulation of p53 was followed by the increasing of pro-apoptotic Bax and decreasing of anti-apoptotic Bcl-2. The increased of cytochrome C levels in cytosol also results in induction of apoptosis. Conclusion The data suggest that eurycomanone was cytotoxic on HepG2 cells by inducing apoptosis through the up-regulation of p53 and Bax, and down-regulation of Bcl-2. PMID:19508737

  14. ADENINE NUCLEOTIDE TRANSLOCASE-1 INDUCES CARDIOMYOCYTE DEATH THROUGH UPREGULATION OF THE PRO-APOPTOTIC PROTEIN BAX

    PubMed Central

    Baines, Christopher P.; Molkentin, Jeffery D.

    2009-01-01

    Overexpression of the adenine nucleotide translocase (ANT) has been shown to be cytotoxic in several cell types. Although ANT was originally proposed to be a critical component of the mitochondrial permeability transition (MPT) pore, recent data have suggested that this may not be the case. We therefore hypothesized that the cytotoxic actions of ANT are through an alternative mechanism, independent of the MPT pore. Infection of cultured neonatal cardiomyocytes with an ANT1-encoding adenovirus induced a gene dosage-dependent increase in cell death. However, ANT1 overexpression failed to induce MPT, and neither pharmacological nor genetic inhibition of the MPT pore was able to prevent ANT1-induced cell death. These data suggested that ANT1-induced death progressed through an MPT pore-independent pathway. Somewhat surprisingly, we observed that protein levels of Bax, a pro-apoptotic Bcl protein, were consistently elevated in ANT1-infected cardiomyocytes. Membranes isolated from ANT1-infected myocytes exhibited significantly increased amounts of membrane-inserted Bax, and immunocytochemistry revealed increased Bax activation in ANT1-infected myocytes. Co-expression with the Bax antagonist Bcl2 was able to greatly reduce the degree of ANT1-induced cell death. Furthermore, Bax/Bak-deficient fibroblasts were resistant to the cytotoxic effects of ANT1 overexpression. Interestingly, ANT1 overexpression was also associated with enhanced production of reactive oxygen species (ROS), and the antioxidant MnTBAP was able to significantly attenuate both the ANT1-induced upregulation of Bax and cell death. Taken together, these data indicate that ANT mediates cell death, not through the MPT pore, but rather via a ROS-dependent upregulation and activation of Bax. PMID:19452617

  15. Meta-review of protein network regulating obesity between validated obesity candidate genes in the white adipose tissue of high-fat diet-induced obese C57BL/6J mice.

    PubMed

    Kim, Eunjung; Kim, Eun Jung; Seo, Seung-Won; Hur, Cheol-Goo; McGregor, Robin A; Choi, Myung-Sook

    2014-01-01

    Worldwide obesity and related comorbidities are increasing, but identifying new therapeutic targets remains a challenge. A plethora of microarray studies in diet-induced obesity models has provided large datasets of obesity associated genes. In this review, we describe an approach to examine the underlying molecular network regulating obesity, and we discuss interactions between obesity candidate genes. We conducted network analysis on functional protein-protein interactions associated with 25 obesity candidate genes identified in a literature-driven approach based on published microarray studies of diet-induced obesity. The obesity candidate genes were closely associated with lipid metabolism and inflammation. Peroxisome proliferator activated receptor gamma (Pparg) appeared to be a core obesity gene, and obesity candidate genes were highly interconnected, suggesting a coordinately regulated molecular network in adipose tissue. In conclusion, the current network analysis approach may help elucidate the underlying molecular network regulating obesity and identify anti-obesity targets for therapeutic intervention.

  16. Neural Stem Cell Transplantation Induces Stroke Recovery by Upregulating Glutamate Transporter GLT-1 in Astrocytes

    PubMed Central

    Russo, Gianluca Luigi; Peruzzotti-Jametti, Luca; Rossi, Silvia; Sandrone, Stefano; Butti, Erica; De Ceglia, Roberta; Bergamaschi, Andrea; Motta, Caterina; Gallizioli, Mattia; Studer, Valeria; Colombo, Emanuela; Farina, Cinthia; Comi, Giancarlo; Politi, Letterio Salvatore; Muzio, Luca; Villani, Claudia; Invernizzi, Roberto William; Hermann, Dirk Matthias; Centonze, Diego

    2016-01-01

    Ischemic stroke is the leading cause of disability, but effective therapies are currently widely lacking. Recovery from stroke is very much dependent on the possibility to develop treatments able to both halt the neurodegenerative process as well as to foster adaptive tissue plasticity. Here we show that ischemic mice treated with neural precursor cell (NPC) transplantation had on neurophysiological analysis, early after treatment, reduced presynaptic release of glutamate within the ipsilesional corticospinal tract (CST), and an enhanced NMDA-mediated excitatory transmission in the contralesional CST. Concurrently, NPC-treated mice displayed a reduced CST degeneration, increased axonal rewiring, and augmented dendritic arborization, resulting in long-term functional amelioration persisting up to 60 d after ischemia. The enhanced functional and structural plasticity relied on the capacity of transplanted NPCs to localize in the peri-ischemic and ischemic area, to promote the upregulation of the glial glutamate transporter 1 (GLT-1) on astrocytes and to reduce peri-ischemic extracellular glutamate. The upregulation of GLT-1 induced by transplanted NPCs was found to rely on the secretion of VEGF by NPCs. Blocking VEGF during the first week after stroke reduced GLT-1 upregulation as well as long-term behavioral recovery in NPC-treated mice. Our results show that NPC transplantation, by modulating the excitatory–inhibitory balance and stroke microenvironment, is a promising therapy to ameliorate disability, to promote tissue recovery and plasticity processes after stroke. SIGNIFICANCE STATEMENT Tissue damage and loss of function occurring after stroke can be constrained by fostering plasticity processes of the brain. Over the past years, stem cell transplantation for repair of the CNS has received increasing interest, although underlying mechanism remain elusive. We here show that neural stem/precursor cell transplantation after ischemic stroke is able to foster

  17. A novel and selective melanin-concentrating hormone receptor 1 antagonist ameliorates obesity and hepatic steatosis in diet-induced obese rodent models.

    PubMed

    Kawata, Yayoi; Okuda, Shoki; Hotta, Natsu; Igawa, Hideyuki; Takahashi, Masashi; Ikoma, Minoru; Kasai, Shizuo; Ando, Ayumi; Satomi, Yoshinori; Nishida, Mayumi; Nakayama, Masaharu; Yamamoto, Syunsuke; Nagisa, Yasutaka; Takekawa, Shiro

    2017-02-05

    Melanin-concentrating hormone (MCH), a cyclic neuropeptide expressed predominantly in the lateral hypothalamus, plays an important role in the control of feeding behavior and energy homeostasis. Mice lacking MCH or MCH1 receptor are resistant to diet-induced obesity (DIO) and MCH1 receptor antagonists show potent anti-obesity effects in preclinical studies, indicating that MCH1 receptor is a promising target for anti-obesity drugs. Moreover, recent studies have suggested the potential of MCH1 receptor antagonists for treatment of non-alcoholic fatty liver disease (NAFLD). In the present study, we show the anti-obesity and anti-hepatosteatosis effect of our novel MCH1 receptor antagonist, Compound A. Repeated oral administration of Compound A resulted in dose-dependent body weight reduction and had an anorectic effect in DIO mice. The body weight lowering effect of Compound A was more potent than that of pair-feeding. Compound A also reduced lipid content and the expression level of lipogenesis-, inflammation-, and fibrosis-related genes in the liver of DIO mice. Conversely, intracerebroventricular infusion of MCH caused induction of hepatic steatosis as well as increase in body weight in high-fat diet-fed wild type mice, but not MCH1 receptor knockout mice. The pair-feeding study revealed the MCH-MCH1 receptor system affects hepatic steatosis through a mechanism that is independent of body weight change. Metabolome analysis demonstrated that Compound A upregulated lipid metabolism-related molecules, such as acylcarnitines and cardiolipins, in the liver. These findings suggest that our novel MCH1 receptor antagonist, Compound A, exerts its beneficial therapeutic effect on NAFLD and obesity through a central MCH-MCH1 receptor pathway.

  18. Exercise-induced bronchospasm, asthma control, and obesity.

    PubMed

    Ostrom, Nancy K; Parsons, Jonathan P; Eid, Nemr S; Craig, Timothy J; Stoloff, Stuart; Hayden, Mary Lou; Colice, Gene L

    2013-01-01

    Exercise-induced bronchospasm (EIB) commonly affects patients with asthma. However, the relationship between EIB and asthma control remains unclear. Exercise limitation due to asthma might lead to reduced physical activity, but little information is available regarding obesity and EIB in asthma. A recent survey evaluated the frequency of EIB and exercise-related respiratory symptoms in a large number of patients with asthma. The survey results were reanalyzed to address any relationship between EIB and asthma control and obesity. A nationwide random sample of children aged 4-12 years (n = 250), adolescents aged 13-17 years (n = 266), and adults aged ≥18 years (n = 1001) with asthma were interviewed by telephone. Questions in the survey addressed asthma symptoms in general, medication use, and height and weight. Asthma control was categorized using established methods in the Expert Panel Report 3. Body mass index (BMI) was calculated using standard nomograms and obesity was defined as a BMI ≥ 30 kg/m(2). Most children (77.6%), adolescents (71.1%), and adults (83.1%) had either "not well" or "very poorly" controlled asthma. Children with "not well" controlled asthma reported a history of EIB significantly more often than those with "well" controlled" asthma. Asthma patients of all ages who had "not well" and "very poorly" controlled asthma described multiple (four or more) exercise-related respiratory symptoms significantly more often than those with "well-controlled" asthma. Obesity was significantly more common in adolescents with "not well" and "very poorly" controlled asthma and adults with "very poorly" controlled asthma. Children, adolescents, and adults with asthma infrequently have well-controlled disease. A history of EIB and exercise-related respiratory symptoms occur more commonly in patients with not well and very poorly controlled asthma. Obesity was found more often in adolescents and adults, but not children, with asthma, which was not well and

  19. Resveratrol prevents rapamycin-induced upregulation of autophagy and selectively induces apoptosis in TSC2-deficient cells.

    PubMed

    Alayev, Anya; Sun, Yang; Snyder, Rose B; Berger, Sara Malka; Yu, Jane J; Holz, Marina K

    2014-01-01

    The mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway is hyperactivated in a variety of cancers and disorders, including lymphangioleiomyomatosis (LAM) and tuberous sclerosis complex (TSC), which are characterized by mutations in tumor suppressors TSC1 or TSC2. The concern with the use of mTORC1 inhibitors, such as rapamycin or its analogs (rapalogs), is that they cause upregulation of autophagy and suppress the negative feedback loop to Akt, which promotes cell survival, causing the therapy to be only partially effective, and relapse occurs upon cessation of treatment. In this study, we investigate the use of rapamycin in combination with resveratrol, a naturally occurring polyphenol, in TSC2-deficient cells. We tested whether such combination would prevent rapamycin-induced upregulation of autophagy and shift the cell fate toward apoptosis. We found that this combination treatment blocked rapamycin-induced upregulation of autophagy and restored inhibition of Akt. Interestingly, the combination of rapamycin and resveratrol selectively promoted apoptosis of TSC2-deficient cells. Thus, the addition of resveratrol to rapamycin treatment may be a promising option for selective and targeted therapy for diseases with TSC loss and mTORC1 hyperactivation.

  20. Hepatic SATB1 induces paracrine activation of hepatic stellate cells and is upregulated by HBx

    PubMed Central

    Gong, Jin; Tu, Wei; Han, Jian; He, Jiayi; Liu, Jingmei; Han, Ping; Wang, Yunwu; Li, Mengke; Liu, Mei; Liao, Jiazhi; Tian, Dean

    2016-01-01

    Chronic hepatitis B virus (HBV) infection is a major cause of chronic liver diseases, but its involvement in hepatic fibrogenesis remains unclear. Special AT-rich binding protein 1 (SATB1) has been implicated in reprogramming chromatin organization and transcription profiles in many cancers and non-cancer-related conditions. We found that hepatic SATB1 expression was significantly up-regulated in fibrotic tissues from chronic hepatitis B virus (HBV)-infected patients and HBV transgenic (HBV-Tg) mouse model. Knockdown of SATB1 in the liver significantly alleviated CCl4-induced fibrosis in HBV-Tg mouse model. Moreover, we suggested HBV encoded x protein (HBx) induced SATB1 expression through activation of JNK and ERK pathways. Enforced expression of SATB1 in hepatocytes promoted the activation and proliferation of hepatic stellate cells (HSCs) by secretion of connective tissue growth factor (CTGF), Interleukin-6 (IL-6) and platelet derived growth factor-A (PDGF-AA). Our findings demonstrated that HBx upregulated hepatic SATB1 which exerted pro-fibrotic effects by paracrine activation of stellate cells in HBV-related fibrosis. PMID:27883059

  1. Ethanol-induced hypothermia and hyperglycemia in genetically obese mice

    SciTech Connect

    Haller, E.W.; Wittmers, L.E. Jr.

    1989-01-01

    Blood glucose and rectal temperatures were monitored in two strains of genetically obese mice (C57 BL/6J ob/ob) prior to and following intragastric ethanol administration in an attempt to relate the hypothermic response to ethanol to extracellular glucose concentration. In contrast to expectation, ethanol administration was typically associated with a hyperglycemia and a hypothermic response. In the ob/ob genotype, the hypothermic response was associated with pronounced hyperglycemia which was more emphatic in older animals. The data support the conclusion that ethanol-induced hypothermia is independent of blood glucose levels. In light of the known sensitivity of ob/ob mice to insulin, it is suggested further that the observed hypothermic response was not a function of the animals' ability to transport glucose into peripheral cells. The observed hyperglycemia of the obese animals was most likely stress-related

  2. Diet-induced obesity: dopamine transporter function, impulsivity and motivation

    PubMed Central

    Narayanaswami, V; Thompson, AC; Cassis, LA; Bardo, MT; Dwoskin, LP

    2013-01-01

    OBJECTIVE A rat model of diet-induced obesity (DIO) was used to determine dopamine transporter (DAT) function, impulsivity and motivation as neurobehavioral outcomes and predictors of obesity. DESIGN To evaluate neurobehavioral alterations following the development of DIO induced by an 8-week high-fat diet (HF) exposure, striatal D2-receptor density, DAT function and expression, extracellular dopamine concentrations, impulsivity, and motivation for high- and low-fat reinforcers were determined. To determine predictors of DIO, neurobehavioral antecedents including impulsivity, motivation for high-fat reinforcers, DAT function and extracellular dopamine were evaluated before the 8-week HF exposure. METHODS Striatal D2-receptor density was determined by in vitro kinetic analysis of [3H]raclopride binding. DAT function was determined using in vitro kinetic analysis of [3H]dopamine uptake, methamphetamine-evoked [3H]dopamine overflow and no-net flux in vivo microdialysis. DAT cell-surface expression was determined using biotinylation and western blotting. Impulsivity and food-motivated behavior were determined using a delay discounting task and progressive ratio schedule, respectively. RESULTS Relative to obesity-resistant (OR) rats, obesity-prone (OP) rats exhibited 18% greater body weight following an 8-week HF-diet exposure, 42% lower striatal D2-receptor density, 30% lower total DAT expression, 40% lower in vitro and in vivo DAT function, 45% greater extracellular dopamine and twofold greater methamphetamine-evoked [3H]dopamine overflow. OP rats exhibited higher motivation for food, and surprisingly, were less impulsive relative to OR rats. Impulsivity, in vivo DAT function and extracellular dopamine concentration did not predict DIO. Importantly, motivation for high-fat reinforcers predicted the development of DIO. CONCLUSION Human studies are limited by their ability to determine if impulsivity, motivation and DAT function are causes or consequences of DIO. The

  3. Undaria pinnatifida and Fucoxanthin Ameliorate Lipogenesis and Markers of Both Inflammation and Cardiovascular Dysfunction in an Animal Model of Diet-Induced Obesity

    PubMed Central

    Grasa-López, Ameyalli; Miliar-García, Ángel; Quevedo-Corona, Lucía; Paniagua-Castro, Norma; Escalona-Cardoso, Gerardo; Reyes-Maldonado, Elba; Jaramillo-Flores, María-Eugenia

    2016-01-01

    Brown algae and its carotenoids have been shown to have a positive influence on obesity and its comorbidities. This study evaluated the effect of Undaria pinnatifida and fucoxanthin on biochemical, physiological and inflammation markers related to obesity and on the expression of genes engaged on white adipose tissue lipid metabolism in a murine model of diet-induced obesity. The treatments improved energy expenditure, β-oxidation and adipogenesis by upregulating PPARα, PGC1α, PPARγ and UCP-1. Adipogenesis was also confirmed by image analysis of the retroperitoneal adipose tissue, by measuring cell area, perimeter and cellular density. Additionally, the treatments, ameliorated adipose tissue accumulation, insulin resistance, blood pressure, cholesterol and triglycerides concentration in serum, and reduced lipogenesis and inflammation by downregulating acetyl-CoA carboxylase (ACC) gene expression, increasing serum concentration and expression of adiponectin as well as downregulating IL-6 expression. Both fucoxanthin and Undaria pinnatifida may be considered for treating obesity and other diseases related. PMID:27527189

  4. Undaria pinnatifida and Fucoxanthin Ameliorate Lipogenesis and Markers of Both Inflammation and Cardiovascular Dysfunction in an Animal Model of Diet-Induced Obesity.

    PubMed

    Grasa-López, Ameyalli; Miliar-García, Ángel; Quevedo-Corona, Lucía; Paniagua-Castro, Norma; Escalona-Cardoso, Gerardo; Reyes-Maldonado, Elba; Jaramillo-Flores, María-Eugenia

    2016-08-03

    Brown algae and its carotenoids have been shown to have a positive influence on obesity and its comorbidities. This study evaluated the effect of Undaria pinnatifida and fucoxanthin on biochemical, physiological and inflammation markers related to obesity and on the expression of genes engaged on white adipose tissue lipid metabolism in a murine model of diet-induced obesity. The treatments improved energy expenditure, β-oxidation and adipogenesis by upregulating PPARα, PGC1α, PPARγ and UCP-1. Adipogenesis was also confirmed by image analysis of the retroperitoneal adipose tissue, by measuring cell area, perimeter and cellular density. Additionally, the treatments, ameliorated adipose tissue accumulation, insulin resistance, blood pressure, cholesterol and triglycerides concentration in serum, and reduced lipogenesis and inflammation by downregulating acetyl-CoA carboxylase (ACC) gene expression, increasing serum concentration and expression of adiponectin as well as downregulating IL-6 expression. Both fucoxanthin and Undaria pinnatifida may be considered for treating obesity and other diseases related.

  5. Obesity

    MedlinePlus

    Obesity means having too much body fat. It is different from being overweight, which means weighing too ... what's considered healthy for his or her height. Obesity occurs over time when you eat more calories ...

  6. Diet-induced Obesity Alters Bone Remodeling Leading to Decreased Femoral Trabecular Bone Mass in Mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Body mass derived from an obesity condition may be detrimental to bone health but the mechanism is unknown. This study was to examine changes in bone structure and serum cytokines related to bone metabolism in obese mice induced by a high-fat diet(HFD). Mice fed the HFD were obese and had higher ser...

  7. Intermittent Hypoxia Exacerbates Metabolic Effects of Diet-Induced Obesity

    PubMed Central

    Drager, Luciano F.; Li, Jianguo; Reinke, Christian; Bevans-Fonti, Shannon; Jun, Jonathan C.; Polotsky, Vsevolod Y.

    2015-01-01

    Obesity causes insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD), but the relative contribution of sleep apnea is debatable. The main aim of this study is to evaluate the effects of chronic intermittent hypoxia (CIH), a hallmark of sleep apnea, on IR and NAFLD in lean mice and mice with diet-induced obesity (DIO). Mice (C57BL/6J), 6–8 weeks of age were fed a high fat (n = 18) or regular (n = 16) diet for 12 weeks and then exposed to CIH or control conditions (room air) for 4 weeks. At the end of the exposure, fasting (5 h) blood glucose, insulin, homeostasis model assessment (HOMA) index, liver enzymes, and intraperitoneal glucose tolerance test (1 g/kg) were measured. In DIO mice, body weight remained stable during CIH and did not differ from control conditions. Lean mice under CIH were significantly lighter than control mice by day 28 (P = 0.002). Compared to lean mice, DIO mice had higher fasting levels of blood glucose, plasma insulin, the HOMA index, and had glucose intolerance and hepatic steatosis at baseline. In lean mice, CIH slightly increased HOMA index (from 1.79 ± 0.13 in control to 2.41 ± 0.26 in CIH; P = 0.05), whereas glucose tolerance was not affected. In contrast, in DIO mice, CIH doubled HOMA index (from 10.1 ± 2.1 in control to 22.5 ± 3.6 in CIH; P < 0.01), and induced severe glucose intolerance. In DIO mice, CIH induced NAFLD, inflammation, and oxidative stress, which was not observed in lean mice. In conclusion, CIH exacerbates IR and induces steatohepatitis in DIO mice, suggesting that CIH may account for metabolic dysfunction in obesity. PMID:21799478

  8. Intermittent hypoxia exacerbates metabolic effects of diet-induced obesity.

    PubMed

    Drager, Luciano F; Li, Jianguo; Reinke, Christian; Bevans-Fonti, Shannon; Jun, Jonathan C; Polotsky, Vsevolod Y

    2011-11-01

    Obesity causes insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD), but the relative contribution of sleep apnea is debatable. The main aim of this study is to evaluate the effects of chronic intermittent hypoxia (CIH), a hallmark of sleep apnea, on IR and NAFLD in lean mice and mice with diet-induced obesity (DIO). Mice (C57BL/6J), 6-8 weeks of age were fed a high fat (n = 18) or regular (n = 16) diet for 12 weeks and then exposed to CIH or control conditions (room air) for 4 weeks. At the end of the exposure, fasting (5 h) blood glucose, insulin, homeostasis model assessment (HOMA) index, liver enzymes, and intraperitoneal glucose tolerance test (1 g/kg) were measured. In DIO mice, body weight remained stable during CIH and did not differ from control conditions. Lean mice under CIH were significantly lighter than control mice by day 28 (P = 0.002). Compared to lean mice, DIO mice had higher fasting levels of blood glucose, plasma insulin, the HOMA index, and had glucose intolerance and hepatic steatosis at baseline. In lean mice, CIH slightly increased HOMA index (from 1.79 ± 0.13 in control to 2.41 ± 0.26 in CIH; P = 0.05), whereas glucose tolerance was not affected. In contrast, in DIO mice, CIH doubled HOMA index (from 10.1 ± 2.1 in control to 22.5 ± 3.6 in CIH; P < 0.01), and induced severe glucose intolerance. In DIO mice, CIH induced NAFLD, inflammation, and oxidative stress, which was not observed in lean mice. In conclusion, CIH exacerbates IR and induces steatohepatitis in DIO mice, suggesting that CIH may account for metabolic dysfunction in obesity.

  9. Upregulation of SQSTM1/p62 contributes to nickel-induced malignant transformation of human bronchial epithelial cells

    PubMed Central

    Huang, Haishan; Zhu, Junlan; Li, Yang; Zhang, Liping; Gu, Jiayan; Xie, Qipeng; Jin, Honglei; Che, Xun; Li, Jingxia; Huang, Chao; Chen, Lung-Chi; Lyu, Jianxin; Gao, Jimin; Huang, Chuanshu

    2016-01-01

    ABSTRACT Chronic lung inflammation is accepted as being associated with the development of lung cancer caused by nickel exposure. Therefore, identifying the molecular mechanisms that lead to a nickel-induced sustained inflammatory microenvironment that causes transformation of human bronchial epithelial cells is of high significance. In the current studies, we identified SQSTM1/p62 as a novel nickel-upregulated protein that is important for nickel-induced inflammatory TNF expression, subsequently resulting in transformation of human bronchial epithelial cells. We found that nickel exposure induced SQSTM1 protein upregulation in human lung epithelial cells in vitro and in mouse lung tissues in vivo. The SQSTM1 upregulation was also observed in human lung squamous cell carcinoma. Further studies revealed that the knockdown of SQSTM1 expression dramatically inhibited transformation of human lung epithelial cells upon chronic nickel exposure, whereas ectopic expression of SQSTM1 promoted such transformation. Mechanistic studies showed that the SQSTM1 upregulation by nickel was the compromised result of upregulating SQSTM1 mRNA transcription and promoting SQSTM1 protein degradation. We demonstrated that nickel-initiated SQSTM1 protein degradation is mediated by macroautophagy/autophagy via an MTOR-ULK1-BECN1 axis, whereas RELA is important for SQSTM1 transcriptional upregulation following nickel exposure. Furthermore, SQSTM1 upregulation exhibited its promotion of nickel-induced cell transformation through exerting an impetus for nickel-induced inflammatory TNF mRNA stability. Consistently, the MTOR-ULK1-BECN1 autophagic cascade acted as an inhibitory effect on nickel-induced TNF expression and cell transformation. Collectively, our results demonstrate a novel SQSTM1 regulatory network that promotes a nickel-induced tumorigenic effect in human bronchial epithelial cells, which is negatively controlled by an autophagic cascade following nickel exposure. PMID:27467530

  10. Coxsackievirus B3 induces viral myocarditis by upregulating toll-like receptor 4 expression.

    PubMed

    Zhao, Zhao; Cai, Tian-Zhi; Lu, Yan; Liu, Wen-Jun; Cheng, Man-Li; Ji, Yu-Qiang

    2015-04-01

    In the present study, we investigated the potential pathogenesis of coxsackievirus B3 (CVB3)-induced viral myocarditis and the promising protective effect of silencing RNA (small interfering RNA, siRNA). One hundred and twenty mice were included in the study, and 30 mice were intraperitoneally inoculated with CVB3 to establish an acute viral myocarditis model. The survival rate was observed for the CVB3-infected mouse model (MOD), and myocardial injury was examined by HE (hematoxylin and eosin) staining assay. Real-time PCR (RT-PCR) and Western blot assay were selected to detect the toll-like receptor 4 (TLR4) expression in myocardial tissues. The TLR4 gene was silenced for the MOD mice, and the effects of this treatment were observed. The results indicate that the expression of TLR4 mRNA and the protein significantly and persistently increased during the progression of CVB3-induced myocarditis. The activities of cardiac enzymes including CK, LDH, AST, and CK-MB were also enhanced in CVB3-induced myocardial tissues. Interestingly, when the TLR4 gene was silenced, the CVB3-induced TLR4 production was significantly decreased and the severity of myocarditis was significantly lessened. In conclusion, CVB3 may induce viral myocarditis by upregulating toll-like receptor 4 expression. The viral myocarditis can be ameliorated by silencing the TLR4 gene in the CVB3 viral myocarditis model, which may be a feasible therapeutic method for treatment of viral myocarditis.

  11. Korean solar salts reduce obesity and alter its related markers in diet-induced obese mice

    PubMed Central

    Ju, Jaehyun; Song, Jia-Le; Park, Eui-Seong; Do, Myoung-Sool

    2016-01-01

    BACKGROUND/OBJECTIVES The aim of this experiments was to show anti-obesity effects of Korean solar salt from different salt fields in diet-induced obese mice. SUBJECTS/METHODS Diet-induced obesity (DIO) was induced by a high-fat diet (HFD; 45% cal from fat) in C57BL/6J mice for eight weeks. The mice were fed with the designated diets (chow diet for Normal, HFD for Control, 0.47%-salt-mixed HFD for purified salt (PS), Guerande solar salt from France (SS-G), solar salt from Y salt field (SS-Y), solar salts from T salt field (SS-T) and S salt field (SS-S)) for another eight weeks. We checked body weight, food efficiency ratio (FER) and tissue weights (liver and epididymal adipose tissue (EAT)), and observed serum concentrations of triacylglycerol (TG), total cholesterol (TC), leptin and insulin. We also evaluated gene expressions of adipogenic / lipogenic mRNAs of C/EBPα, PPARγ and FAS and beta-oxidation-related factors (PPARα and CPT-1) in liver and EAT. The mineral composition of salt samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). RESULTS SS-T and SS-S significantly reduced body weight gain, FER, and weight of EAT compared to control and other samples (P < 0.05). SS-T and SS-S also significantly decreased serum levels of TG, TC, leptin and insulin (P < 0.05). SS-T and SS-S suppressed expressions of adipogenic / lipogenic mRNAs in liver and EAT, while promoting expression of beta-oxidation-related factors. The lowest sodium concentration was observed in SS-T (30.30 ± 0.59%), and the lowest sodium-to-potassium (Na/K) ratio was found in SS-S (17.81). CONCLUSIONS Our study shows that well-processed Korean solar salt may have anti-obesity effects in vivo, probably owing to its differences in mineral composition and other components, presumably resulting from the manufacturing processes. Further research is needed into the mechanism and to explore optimal manufacturing processes. PMID:27909561

  12. Voglibose administration regulates body weight and energy intake in high fat-induced obese mice.

    PubMed

    Do, Hyun Ju; Jin, Taeon; Chung, Ji Hyung; Hwang, Ji Won; Shin, Min-Jeong

    2014-01-17

    We tested whether long-term administration of voglibose (VO) prevents diet induced obesity in addition to hypoglycemic effects in high fat fed mice and further investigated the underlying mechanisms by which voglibose exerts its weight lowering effect. Male C57BL/6 mice were fed ad libitum for 12 weeks with the control diet (CTL), high-fat diet (HFD) or the HFD with VO supplementations. Blood lipid profile, plasma leptin levels and hepatic triglyceride content, as well as expressions of genes involved in appetite and mitochondrial function were examined. The results showed that VO significantly reduced body weight, fat mass and energy intakes in high fat fed mice. VO showed improved metabolic profiles including blood glucose, triglyceride and free fatty acid. Elevated levels of plasma leptin in HFD were significantly reduced with the VO, furthermore, VO modulated the hypothalamic expressions of leptin receptors and appetite related genes. VO showed the upregulated expressions of PGC-1 in the liver and epididymal adipose tissue. In conclusion, VO may exert antiobesity properties through reductions in energy intake and improvement in mitochondrial function, indicating that VO has potential therapeutic use in patients with obesity, type 2 diabetes, and related complications.

  13. Serotonin Improves High Fat Diet Induced Obesity in Mice.

    PubMed

    Watanabe, Hitoshi; Nakano, Tatsuya; Saito, Ryo; Akasaka, Daisuke; Saito, Kazuki; Ogasawara, Hideki; Minashima, Takeshi; Miyazawa, Kohtaro; Kanaya, Takashi; Takakura, Ikuro; Inoue, Nao; Ikeda, Ikuo; Chen, Xiangning; Miyake, Masato; Kitazawa, Haruki; Shirakawa, Hitoshi; Sato, Kan; Tahara, Kohji; Nagasawa, Yuya; Rose, Michael T; Ohwada, Shyuichi; Watanabe, Kouichi; Aso, Hisashi

    2016-01-01

    There are two independent serotonin (5-HT) systems of organization: one in the central nervous system and the other in the periphery. 5-HT affects feeding behavior and obesity in the central nervous system. On the other hand, peripheral 5-HT also may play an important role in obesity, as it has been reported that 5-HT regulates glucose and lipid metabolism. Here we show that the intraperitoneal injection of 5-HT to mice inhibits weight gain, hyperglycemia and insulin resistance and completely prevented the enlargement of intra-abdominal adipocytes without having any effect on food intake when on a high fat diet, but not on a chow diet. 5-HT increased energy expenditure, O2 consumption and CO2 production. This novel metabolic effect of peripheral 5-HT is critically related to a shift in the profile of muscle fiber type from fast/glycolytic to slow/oxidative in soleus muscle. Additionally, 5-HT dramatically induced an increase in the mRNA expression of peroxisome proliferator-activated receptor coactivator 1α (PGC-1α)-b and PGC-1α-c in soleus muscle. The elevation of these gene mRNA expressions by 5-HT injection was inhibited by treatment with 5-HT receptor (5HTR) 2A or 7 antagonists. Our results demonstrate that peripheral 5-HT may play an important role in the relief of obesity and other metabolic disorders by accelerating energy consumption in skeletal muscle.

  14. Diet-Induced Obesity and Circadian Disruption of Feeding Behavior.

    PubMed

    Blancas-Velazquez, Aurea; Mendoza, Jorge; Garcia, Alexandra N; la Fleur, Susanne E

    2017-01-01

    Feeding behavior shows a rhythmic daily pattern, which in nocturnal rodents is observed mainly during the dark period. This rhythmicity is under the influence of the hypothalamic suprachiasmatic nucleus (SCN), the main biological clock. Nevertheless, various studies have shown that in rodent models of obesity, using high-energy diets, the general locomotor activity and feeding rhythms can be disrupted. Here, we review the data on the effects of diet-induced obesity (DIO) on locomotor activity and feeding patterns, as well as the effect on the brain sites within the neural circuitry involved in metabolic and rewarding feeding behavior. In general, DIO may alter locomotor activity by decreasing total activity. On the other hand, DIO largely alters eating patterns, producing increased overall ingestion and number of eating bouts that can extend to the resting period. Furthermore, within the hypothalamic areas, little effect has been reported on the molecular circadian mechanism in DIO animals with ad libitum hypercaloric diets and little or no data exist so far on its effects on the reward system areas. We further discuss the possibility of an uncoupling of metabolic and reward systems in DIO and highlight a gap of circadian and metabolic research that may help to better understand the implications of obesity.

  15. Diet-Induced Obesity and Circadian Disruption of Feeding Behavior

    PubMed Central

    Blancas-Velazquez, Aurea; Mendoza, Jorge; Garcia, Alexandra N.; la Fleur, Susanne E.

    2017-01-01

    Feeding behavior shows a rhythmic daily pattern, which in nocturnal rodents is observed mainly during the dark period. This rhythmicity is under the influence of the hypothalamic suprachiasmatic nucleus (SCN), the main biological clock. Nevertheless, various studies have shown that in rodent models of obesity, using high-energy diets, the general locomotor activity and feeding rhythms can be disrupted. Here, we review the data on the effects of diet-induced obesity (DIO) on locomotor activity and feeding patterns, as well as the effect on the brain sites within the neural circuitry involved in metabolic and rewarding feeding behavior. In general, DIO may alter locomotor activity by decreasing total activity. On the other hand, DIO largely alters eating patterns, producing increased overall ingestion and number of eating bouts that can extend to the resting period. Furthermore, within the hypothalamic areas, little effect has been reported on the molecular circadian mechanism in DIO animals with ad libitum hypercaloric diets and little or no data exist so far on its effects on the reward system areas. We further discuss the possibility of an uncoupling of metabolic and reward systems in DIO and highlight a gap of circadian and metabolic research that may help to better understand the implications of obesity. PMID:28223912

  16. Serotonin Improves High Fat Diet Induced Obesity in Mice

    PubMed Central

    Akasaka, Daisuke; Saito, Kazuki; Ogasawara, Hideki; Minashima, Takeshi; Miyazawa, Kohtaro; Kanaya, Takashi; Takakura, Ikuro; Inoue, Nao; Ikeda, Ikuo; Chen, Xiangning; Miyake, Masato; Kitazawa, Haruki; Shirakawa, Hitoshi; Sato, Kan; Tahara, Kohji; Nagasawa, Yuya; Rose, Michael T.; Ohwada, Shyuichi; Watanabe, Kouichi; Aso, Hisashi

    2016-01-01

    There are two independent serotonin (5-HT) systems of organization: one in the central nervous system and the other in the periphery. 5-HT affects feeding behavior and obesity in the central nervous system. On the other hand, peripheral 5-HT also may play an important role in obesity, as it has been reported that 5-HT regulates glucose and lipid metabolism. Here we show that the intraperitoneal injection of 5-HT to mice inhibits weight gain, hyperglycemia and insulin resistance and completely prevented the enlargement of intra-abdominal adipocytes without having any effect on food intake when on a high fat diet, but not on a chow diet. 5-HT increased energy expenditure, O2 consumption and CO2 production. This novel metabolic effect of peripheral 5-HT is critically related to a shift in the profile of muscle fiber type from fast/glycolytic to slow/oxidative in soleus muscle. Additionally, 5-HT dramatically induced an increase in the mRNA expression of peroxisome proliferator-activated receptor coactivator 1α (PGC-1α)-b and PGC-1α-c in soleus muscle. The elevation of these gene mRNA expressions by 5-HT injection was inhibited by treatment with 5-HT receptor (5HTR) 2A or 7 antagonists. Our results demonstrate that peripheral 5-HT may play an important role in the relief of obesity and other metabolic disorders by accelerating energy consumption in skeletal muscle. PMID:26766570

  17. Calorie restriction improves cognitive decline via up-regulation of brain-derived neurotrophic factor: tropomyosin-related kinase B in hippocampus ofobesity-induced hypertensive rats.

    PubMed

    Kishi, Takuya; Hirooka, Yoshitaka; Nagayama, Tomomi; Isegawa, Kengo; Katsuki, Masato; Takesue, Ko; Sunagawa, Kenji

    2015-01-01

    In metabolic syndrome (MetS), previous studies have suggested that cognitive decline is worsened. Among the factors associated with cognition, decreased brain-derived neurotrophic factor (BDNF) in the hippocampus causes cognitive decline. We previously reported that exercise training with calorie restriction yielded protection against cognitive decline via BDNF in the hippocampus of hypertensive rats. The aim of the present study was to determine whether or not calorie restriction results in protection against cognitive decline via BDNF and its receptor tropomyosin-related kinase B (TrkB) in the hippocampus of MetS model rats. We divided dietary-induced obesity-prone and hypertensive rats (OP), as metabolic syndrome model rats, into three groups, fed with a high fat diet (HF), treated with calorie restriction (CR) plus vehicle, and treated with CR and ANA-12 (a TrkB antagonist) (CR+A). After treatment for 28 days, body weight, insulin, fasting blood glucose, adiponectin, systolic blood pressure, and oxidative stress in the hippocampus were significantly lower, and BDNF expression in the hippocampus was significantly higher in CR and CR+A than in HF. Cognitive performance determined by the Morris water maze test was significantly higher in CR than in HF, whereas the benefit was attenuated in CR+A. In conclusion, calorie restriction protects against cognitive decline via up-regulation of BDNF/TrkB through an antioxidant effect in the hippocampus of dietary-induced obesity rats.

  18. Induction of heme oxygenase-1 with dietary quercetin reduces obesity-induced hepatic inflammation through macrophage phenotype switching

    PubMed Central

    Kim, Chu-Sook; Choi, Hye-Seon; Joe, Yeonsoo; Chung, Hun Taeg

    2016-01-01

    BACKGROUND/OBJECTIVES Obesity-induced steatohepatitis accompanied by activated hepatic macrophages/Kupffer cells facilitates the progression of hepatic fibrinogenesis and exacerbates metabolic derangements such as insulin resistance. Heme oxyganase-1 (HO-1) modulates tissue macrophage phenotypes and thus is implicated in protection against inflammatory diseases. Here, we show that the flavonoid quercetin reduces obesity-induced hepatic inflammation by inducing HO-1, which promotes hepatic macrophage polarization in favor of the M2 phenotype. MATERIALS/METHODS Male C57BL/6 mice were fed a regular diet (RD), high-fat diet (HFD), or HFD supplemented with quercetin (HF+Que, 0.5g/kg diet) for nine weeks. Inflammatory cytokines and macrophage markers were measured by ELISA and RT-PCR, respectively. HO-1 protein was measured by Western blotting. RESULTS Quercetin supplementation decreased levels of inflammatory cytokines (TNFα, IL-6) and increased that of the anti-inflammatory cytokine (IL-10) in the livers of HFD-fed mice. This was accompanied by upregulation of M2 macrophage marker genes (Arg-1, Mrc1) and downregulation of M1 macrophage marker genes (TNFα, NOS2). In co-cultures of lipid-laden hepatocytes and macrophages, treatment with quercetin induced HO-1 in the macrophages, markedly suppressed expression of M1 macrophage marker genes, and reduced release of MCP-1. Moreover, these effects of quercetin were blunted by an HO-1 inhibitor and deficiency of nuclear factor E2-related factor 2 (Nrf2) in macrophages. CONCLUSIONS Quercetin reduces obesity-induced hepatic inflammation by promoting macrophage phenotype switching. The beneficial effect of quercetin is associated with Nrf2-mediated HO-1 induction. Quercetin may be a useful dietary factor for protecting against obesity-induced steatohepatitis. PMID:27909560

  19. Armet, a UPR-upregulated protein, inhibits cell proliferation and ER stress-induced cell death

    SciTech Connect

    Apostolou, Andria; Shen Yuxian; Liang Yan; Luo Jun; Fang Shengyun

    2008-08-01

    The accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress that initiates the unfolded protein response (UPR). UPR activates both adaptive and apoptotic pathways, which contribute differently to disease pathogenesis. To further understand the functional mechanisms of UPR, we identified 12 commonly UPR-upregulated genes by expression microarray analysis. Here, we describe characterization of Armet/MANF, one of the 12 genes whose function was not clear. We demonstrated that the Armet/MANF protein was upregulated by various forms of ER stress in several cell lines as well as by cerebral ischemia of rat. Armet/MANF was localized in the ER and Golgi and was also a secreted protein. Silencing Armet/MANF by siRNA oligos in HeLa cells rendered cells more susceptible to ER stress-induced death, but surprisingly increased cell proliferation and reduced cell size. Overexpression of Armet/MANF inhibited cell proliferation and improved cell viability under glucose-free conditions and tunicamycin treatment. Based on its inhibitory properties for both proliferation and cell death we have demonstrated, Armet is, thus, a novel secreted mediator of the adaptive pathway of UPR.

  20. Expression of new loci associated with obesity in diet-induced obese rats: from genetics to physiology.

    PubMed

    Gutierrez-Aguilar, Ruth; Kim, Dong-Hoon; Woods, Stephen C; Seeley, Randy J

    2012-02-01

    Genome-wide association studies (GWAS) are a powerful tool for revealing genes associated with common human obesity. New loci associated with obesity have recently been reported, but their function and metabolic implications remain to be elucidated. In order to begin identifying the role of some of these obesity-related loci, the closest genes to the polymorphism of each locus were selected and their expression was compared in the hypothalamus, adipose tissue, liver, soleus muscle, and extensor digitorum longus muscle (EDL) of Long-Evans rats maintained on chow or a high-fat diet (HFD) for 6 weeks. From a total of 19 genes analyzed, seven genes (ETV5, FTO, GNPDA2, KCTD15, TMEM18, MC4R, and SH2B1) were down-regulated in the hypothalamus of HFD compared to chow-fed rats. In adipose tissue of rats fed on HFD, the mRNA levels of BCDIN3, KCTD15, and SULT1A1 were down-regulated, whereas those of MTCH2, PTER, and TUFM were up-regulated. In the liver, three genes were up-regulated (PTER, SULT1A1, and TUFM) in HFD relative to chow-fed rats, and TMEM18 was down-regulated. Finally, in soleus muscle of HFD-fed rats, BCDIN3, BDNF, and TMEM18 were down-regulated, and in the EDL muscle SH2B1 and TUFM were up-regulated. mRNA levels in the hypothalamus were compared between fed and fasted states, and only KCTD15 was down-regulated during fasting when fed a chow diet. In conclusion, novel genes found to be associated with obesity are regulated by a HFD and the mRNA levels of KCTD15 is dependent on the nutritional status. These results suggest a potential role of these genes in the regulation of energy balance.

  1. Cellular and Molecular Mechanisms of Heat Stress-Induced Up-Regulation of Occludin Protein Expression

    PubMed Central

    Dokladny, Karol; Ye, Dongmei; Kennedy, John C.; Moseley, Pope L.; Ma, Thomas Y.

    2008-01-01

    The heat stress (HS)-induced increase in occludin protein expression has been postulated to be a protective response against HS-induced disruption of the intestinal epithelial tight junction barrier. The aim of this study was to elucidate the cellular and molecular processes that mediate the HS-induced up-regulation of occludin expression in Caco-2 cells. Exposure to HS (39°C or 41°C) resulted in increased expression of occludin protein; this was preceded by an increase in occludin mRNA transcription and promoter activity. HS-induced activation of heat shock factor-1 (HSF-1) resulted in cytoplasmic-to-nuclear translocation of HSF-1 and binding to its binding motif in the occludin promoter region. HSF-1 activation was associated with an increase in occludin promoter activity, mRNA transcription, and protein expression; which were abolished by the HSF-1 inhibitor quercetin. Targeted HSF-1 knock-down by siRNA transfection inhibited the HSF-1-induced increase in occulin expression and junctional localization of occulin protein. Site-directed mutagenesis of the HSF-1 binding motif in the occludin promoter region inhibited HS-induced binding of HSF-1 to the occludin promoter region and subsequent promoter activity. In conclusion, our data show for the first time that the HS-induced increase in occludin protein expression is mediated by HSF-1 activation and subsequent binding of HSF-1 to the occludin promoter, which initiates a series of molecular and cellular events culminating in increased junctional localization of occludin protein. PMID:18276783

  2. Cucurbitacin E Induces Autophagy via Downregulating mTORC1 Signaling and Upregulating AMPK Activity.

    PubMed

    Zha, Qing-Bing; Zhang, Xiao-Yu; Lin, Qiu-Ru; Xu, Li-Hui; Zhao, Gao-Xiang; Pan, Hao; Zhou, Dan; Ouyang, Dong-Yun; Liu, Ze-Huan; He, Xian-Hui

    2015-01-01

    Cucurbitacins, the natural triterpenoids possessing many biological activities, have been reported to suppress the mTORC1/p70S6K pathway and to induce autophagy. However, the correlation between such activities is largely unknown. In this study, we addressed this issue in human cancer cells in response to cucurbitacin E (CuE) treatment. Our results showed that CuE induced autophagy as evidenced by the formation of LC3-II and colocalization of punctate LC3 with the lysosomal marker LAMP2 in HeLa and MCF7 cells. However, CuE induced much lower levels of autophagy in ATG5-knocked down cells and failed to induce autophagy in DU145 cells lacking functional ATG5 expression, suggesting the dependence of CuE-induced autophagy on ATG5. Consistent with autophagy induction, mTORC1 activity (as reflected by p70S6K and ULK1S758 phosphorylation) was inhibited by CuE treatment. The suppression of mTORC1 activity was further confirmed by reduced recruitment of mTOR to the lysosome, which is the activation site of mTORC1. In contrast, CuE rapidly activated AMPK leading to increased phosphorylation of its substrates. AMPK activation contributed to CuE-induced suppression of mTORC1/p70S6K signaling and autophagy induction, since AMPK knockdown diminished these effects. Collectively, our data suggested that CuE induced autophagy in human cancer cells at least partly via downregulation of mTORC1 signaling and upregulation of AMPK activity.

  3. The lysyl oxidase inhibitor β-aminopropionitrile reduces body weight gain and improves the metabolic profile in diet-induced obesity in rats

    PubMed Central

    Miana, María; Galán, María; Martínez-Martínez, Ernesto; Varona, Saray; Jurado-López, Raquel; Bausa-Miranda, Belén; Antequera, Alfonso; Luaces, María; Martínez-González, José; Rodríguez, Cristina; Cachofeiro, Victoria

    2015-01-01

    ABSTRACT Extracellular matrix (ECM) remodelling of the adipose tissue plays a pivotal role in the pathophysiology of obesity. The lysyl oxidase (LOX) family of amine oxidases, including LOX and LOX-like (LOXL) isoenzymes, controls ECM maturation, and upregulation of LOX activity is essential in fibrosis; however, its involvement in adipose tissue dysfunction in obesity is unclear. In this study, we observed that LOX is the main isoenzyme expressed in human adipose tissue and that its expression is strongly upregulated in samples from obese individuals that had been referred to bariatric surgery. LOX expression was also induced in the adipose tissue from male Wistar rats fed a high-fat diet (HFD). Interestingly, treatment with β-aminopropionitrile (BAPN), a specific and irreversible inhibitor of LOX activity, attenuated the increase in body weight and fat mass that was observed in obese animals and shifted adipocyte size toward smaller adipocytes. BAPN also ameliorated the increase in collagen content that was observed in adipose tissue from obese animals and improved several metabolic parameters – it ameliorated glucose and insulin levels, decreased homeostasis model assessment (HOMA) index and reduced plasma triglyceride levels. Furthermore, in white adipose tissue from obese animals, BAPN prevented the downregulation of adiponectin and glucose transporter 4 (GLUT4), as well as the increase in suppressor of cytokine signaling 3 (SOCS3) and dipeptidyl peptidase 4 (DPP4) levels, triggered by the HFD. Likewise, in the TNFα-induced insulin-resistant 3T3-L1 adipocyte model, BAPN prevented the downregulation of adiponectin and GLUT4 and the increase in SOCS3 levels, and consequently normalised insulin-stimulated glucose uptake. Therefore, our data provide evidence that LOX plays a pathologically relevant role in the metabolic dysfunction induced by obesity and emphasise the interest of novel pharmacological interventions that target adipose tissue fibrosis and LOX

  4. The lysyl oxidase inhibitor β-aminopropionitrile reduces body weight gain and improves the metabolic profile in diet-induced obesity in rats.

    PubMed

    Miana, María; Galán, María; Martínez-Martínez, Ernesto; Varona, Saray; Jurado-López, Raquel; Bausa-Miranda, Belén; Antequera, Alfonso; Luaces, María; Martínez-González, José; Rodríguez, Cristina; Cachofeiro, Victoria

    2015-06-01

    Extracellular matrix (ECM) remodelling of the adipose tissue plays a pivotal role in the pathophysiology of obesity. The lysyl oxidase (LOX) family of amine oxidases, including LOX and LOX-like (LOXL) isoenzymes, controls ECM maturation, and upregulation of LOX activity is essential in fibrosis; however, its involvement in adipose tissue dysfunction in obesity is unclear. In this study, we observed that LOX is the main isoenzyme expressed in human adipose tissue and that its expression is strongly upregulated in samples from obese individuals that had been referred to bariatric surgery. LOX expression was also induced in the adipose tissue from male Wistar rats fed a high-fat diet (HFD). Interestingly, treatment with β-aminopropionitrile (BAPN), a specific and irreversible inhibitor of LOX activity, attenuated the increase in body weight and fat mass that was observed in obese animals and shifted adipocyte size toward smaller adipocytes. BAPN also ameliorated the increase in collagen content that was observed in adipose tissue from obese animals and improved several metabolic parameters - it ameliorated glucose and insulin levels, decreased homeostasis model assessment (HOMA) index and reduced plasma triglyceride levels. Furthermore, in white adipose tissue from obese animals, BAPN prevented the downregulation of adiponectin and glucose transporter 4 (GLUT4), as well as the increase in suppressor of cytokine signaling 3 (SOCS3) and dipeptidyl peptidase 4 (DPP4) levels, triggered by the HFD. Likewise, in the TNFα-induced insulin-resistant 3T3-L1 adipocyte model, BAPN prevented the downregulation of adiponectin and GLUT4 and the increase in SOCS3 levels, and consequently normalised insulin-stimulated glucose uptake. Therefore, our data provide evidence that LOX plays a pathologically relevant role in the metabolic dysfunction induced by obesity and emphasise the interest of novel pharmacological interventions that target adipose tissue fibrosis and LOX activity for

  5. Retinoblastoma protein promotes oxidative phosphorylation through upregulation of glycolytic genes in oncogene-induced senescent cells.

    PubMed

    Takebayashi, Shin-Ichiro; Tanaka, Hiroshi; Hino, Shinjiro; Nakatsu, Yuko; Igata, Tomoka; Sakamoto, Akihisa; Narita, Masashi; Nakao, Mitsuyoshi

    2015-08-01

    Metabolism is closely linked with cellular state and biological processes, but the mechanisms controlling metabolic properties in different contexts remain unclear. Cellular senescence is an irreversible growth arrest induced by various stresses, which exhibits active secretory and metabolic phenotypes. Here, we show that retinoblastoma protein (RB) plays a critical role in promoting the metabolic flow by activating both glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) in cells that have undergone oncogene-induced senescence (OIS). A combination of real-time metabolic monitoring, and metabolome and gene expression analyses showed that OIS-induced fibroblasts developed an accelerated metabolic flow. The loss of RB downregulated a series of glycolytic genes and simultaneously reduced metabolites produced from the glycolytic pathway, indicating that RB upregulates glycolytic genes in OIS cells. Importantly, both mitochondrial OXPHOS and glycolytic activities were abolished in RB-depleted or downstream glycolytic enzyme-depleted OIS cells, suggesting that RB-mediated glycolytic activation induces a metabolic flux into the OXPHOS pathway. Collectively, our findings reveal that RB essentially functions in metabolic remodeling and the maintenance of the active energy production in OIS cells.

  6. Retinoblastoma protein promotes oxidative phosphorylation through upregulation of glycolytic genes in oncogene-induced senescent cells

    PubMed Central

    Takebayashi, Shin-ichiro; Tanaka, Hiroshi; Hino, Shinjiro; Nakatsu, Yuko; Igata, Tomoka; Sakamoto, Akihisa; Narita, Masashi; Nakao, Mitsuyoshi

    2015-01-01

    Metabolism is closely linked with cellular state and biological processes, but the mechanisms controlling metabolic properties in different contexts remain unclear. Cellular senescence is an irreversible growth arrest induced by various stresses, which exhibits active secretory and metabolic phenotypes. Here, we show that retinoblastoma protein (RB) plays a critical role in promoting the metabolic flow by activating both glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) in cells that have undergone oncogene-induced senescence (OIS). A combination of real-time metabolic monitoring, and metabolome and gene expression analyses showed that OIS-induced fibroblasts developed an accelerated metabolic flow. The loss of RB downregulated a series of glycolytic genes and simultaneously reduced metabolites produced from the glycolytic pathway, indicating that RB upregulates glycolytic genes in OIS cells. Importantly, both mitochondrial OXPHOS and glycolytic activities were abolished in RB-depleted or downstream glycolytic enzyme-depleted OIS cells, suggesting that RB-mediated glycolytic activation induces a metabolic flux into the OXPHOS pathway. Collectively, our findings reveal that RB essentially functions in metabolic remodeling and the maintenance of the active energy production in OIS cells. PMID:26009982

  7. Skeletal muscle atrophy is induced by Fbxw7β via atrogene upregulation.

    PubMed

    Shin, Kyungshin; Ko, Young-Gyu; Jeong, Jaemin; Kwon, Heechung

    2017-02-01

    Muscle atrophy decreases skeletal muscle mass and is induced by inherited cachectic symptoms, genetic disorders, and sarcopenia. However, the molecular pathways associated with the onset of muscle atrophy are still unclear. In this study, we evaluated Fbxw7β, a gene associated with the development of muscle atrophy in vitro and in vivo. Among the three Fbxw7 isoforms, ectopically overexpressed Fbxw7β induced the expression of myogenin and major atrogene markers (atrogin-1 and MuRF-1) and reduced myoblast differentiation. In addition, endogenous expression of Fbxw7β was also upregulated by dexamethasone, which mimics muscle atrophy in vitro, accompanied by induction of myogenin and atrogene expression in primary myoblasts. Functional analysis of Fbxw7β using short hairpin RNA (shRNA) and a dominant-negative mutant (ΔFbox) suggested that Fbxw7β regulated muscle atrophy in vitro and in vivo. In particular, ΔFbox did not reduce the sizes of muscle fibers and did not induce myogenin and atrogene expression in vivo. Therefore, our findings demonstrated, for the first time, that Fbxw7β induced muscle atrophic phenotypes via atrogenes in adult muscle precursor cells and myofibers; this mechanism could be a potential therapeutic target for skeletal muscle atrophy.

  8. Traumatic brain injury and obesity induce persistent central insulin resistance.

    PubMed

    Karelina, Kate; Sarac, Benjamin; Freeman, Lindsey M; Gaier, Kristopher R; Weil, Zachary M

    2016-04-01

    Traumatic brain injury (TBI)-induced impairments in cerebral energy metabolism impede tissue repair and contribute to delayed functional recovery. Moreover, the transient alteration in brain glucose utilization corresponds to a period of increased vulnerability to the negative effects of a subsequent TBI. In order to better understand the factors contributing to TBI-induced central metabolic dysfunction, we examined the effect of single and repeated TBIs on brain insulin signalling. Here we show that TBI induced acute brain insulin resistance, which resolved within 7 days following a single injury but persisted until 28 days following repeated injuries. Obesity, which causes brain insulin resistance and neuroinflammation, exacerbated the consequences of TBI. Obese mice that underwent a TBI exhibited a prolonged reduction of Akt (also known as protein kinase B) signalling, exacerbated neuroinflammation (microglial activation), learning and memory deficits, and anxiety-like behaviours. Taken together, the transient changes in brain insulin sensitivity following TBI suggest a reduced capacity of the injured brain to respond to the neuroprotective and anti-inflammatory actions of insulin and Akt signalling, and thus may be a contributing factor for the damaging neuroinflammation and long-lasting deficits that occur following TBI.

  9. Inhibitory effect of atorvastatin on AGE-induced HCAEC apoptosis by upregulating HSF-1 protein.

    PubMed

    Li, Ying; Li, Jiming; Cui, Li; Lai, Yan; Yao, Yian; Zhang, Yibo; Pang, Xiufeng; Wang, Jie; Liu, Xuebo

    2013-06-01

    This study evaluates effect and mechanism of atorvastatin on human coronary artery endothelial cells (HCAEC) apoptosis. Results have shown that HCAEC apoptosis had increased with increasing concentration of AGEs. Atorvastatin may decrease HCAEC apoptosis, but the effect can be attenuated by PI3K inhibitor. Secretion of PI3K and P-Akt in HCAEC increased with increasing concentration of AGEs. Secretion of PI3K in HCAEC may be decreased by atorvastatin. The effect may be attenuated by PI3K inhibitor. HSF-1, HSP-70 mRNA expression level decreased with increasing concentration of AGEs. Atorvastatin may attenuate AGEs-induced HSF-1, HSP-70 mRNA expression in HCAEC, but the effect can be attenuated by PI3K inhibitor. It can be concluded that AGE can dose-dependently promote HCAEC apoptosis by the PI3K/AKT pathway. Atorvastatin may attenuate the effect possibly by upregulating HSF-1.

  10. Fascaplysin sensitizes cells to TRAIL-induced apoptosis through upregulating DR5 expression

    NASA Astrophysics Data System (ADS)

    Wang, Feng; Chen, Haimin; Yan, Xiaojun; Zheng, Yanling

    2013-05-01

    This study investigated the molecular mechanism of anti-tumor effect of fascaplysin, a nitrogenous red pigment firstly isolated from a marine sponge. Microarray analysis show that the TNF and TNF receptor superfamily in human umbilical vein endothelial cells (HUVEC) and human hepatocarcinoma cells (BEL-7402) were significantly regulated by fascaplysin. Western Blot results reveal that fascaplysin increased the expression of cleaved caspase-9, active caspase-3, and decreased the level of procaspase-8 and Bid. Flow cytometry and cytotoxicity tests indicate that fascaplysin sensitized cells to tumor necrosis-related apoptosisinducing ligand-(TRAIL) induced apoptosis, which was markedly blocked by TRAIL R2/Fc chimera, a dominant negative form of TRAIL receptor DR5. Therefore, our results demonstrate that fascaplysin promotes apoptosis through the activation of TRAIL signaling pathway by upregulating DR5 expression.

  11. Exercise-induced up-regulation of MMP-1 and IL-8 genes in endurance horses

    PubMed Central

    Cappelli, Katia; Felicetti, Michela; Capomaccio, Stefano; Pieramati, Camillo; Silvestrelli, Maurizio; Verini-Supplizi, Andrea

    2009-01-01

    Background The stress response is a critical factor in the training of equine athletes; it is important for performance and for protection of the animal against physio-pathological disorders. In this study, the molecular mechanisms involved in the response to acute and strenuous exercise were investigated using peripheral blood mononuclear cells (PBMCs). Results Quantitative real-time PCR (qRT-PCR) was used to detect modifications in transcription levels of the genes for matrix metalloproteinase-1 (MMP-1) and interleukin 8 (IL-8), which were derived from previous genome-wide expression analysis. Significant up-regulation of these two genes was found in 10 horses that had completed a race of 90–120 km in a time-course experimental design. Conclusion These results suggest that MMP-1 and IL-8 are both involved in the exercise-induced stress response, and this represents a starting point from which to understand the adaptive responses to this phenomenon. PMID:19552796

  12. Humanin Protects RPE Cells from Endoplasmic Reticulum Stress-Induced Apoptosis by Upregulation of Mitochondrial Glutathione

    PubMed Central

    Matsunaga, Douglas; Sreekumar, Parameswaran G.; Ishikawa, Keijiro; Terasaki, Hiroto; Barron, Ernesto; Cohen, Pinchas

    2016-01-01

    Humanin (HN) is a small mitochondrial-encoded peptide with neuroprotective properties. We have recently shown protection of retinal pigmented epithelium (RPE) cells by HN in oxidative stress; however, the effect of HN on endoplasmic reticulum (ER) stress has not been evaluated in any cell type. Our aim here was to study the effect of HN on ER stress-induced apoptosis in RPE cells with a specific focus on ER-mitochondrial cross-talk. Dose dependent effects of ER stressors (tunicamycin (TM), brefeldin A, and thapsigargin) were studied after 12 hr of treatment in confluent primary human RPE cells with or without 12 hr of HN pretreatment (1–20 μg/mL). All three ER stressors induced RPE cell apoptosis in a dose dependent manner. HN pretreatment significantly decreased the number of apoptotic cells with all three ER stressors in a dose dependent manner. HN pretreatment similarly protected U-251 glioma cells from TM-induced apoptosis in a dose dependent manner. HN pretreatment significantly attenuated activation of caspase 3 and ER stress-specific caspase 4 induced by TM. TM treatment increased mitochondrial superoxide production, and HN co-treatment resulted in a decrease in mitochondrial superoxide compared to TM treatment alone. We further showed that depleted mitochondrial glutathione (GSH) levels induced by TM were restored with HN co-treatment. No significant changes were found for the expression of several antioxidant enzymes between TM and TM plus HN groups except for the expression of glutamylcysteine ligase catalytic subunit (GCLC), the rate limiting enzyme required for GSH biosynthesis, which is upregulated with TM and TM+HN treatment. These results demonstrate that ER stress promotes mitochondrial alterations in RPE that lead to apoptosis. We further show that HN has a protective effect against ER stress-induced apoptosis by restoring mitochondrial GSH. Thus, HN should be further evaluated for its therapeutic potential in disorders linked to ER stress. PMID

  13. Humanin Protects RPE Cells from Endoplasmic Reticulum Stress-Induced Apoptosis by Upregulation of Mitochondrial Glutathione.

    PubMed

    Matsunaga, Douglas; Sreekumar, Parameswaran G; Ishikawa, Keijiro; Terasaki, Hiroto; Barron, Ernesto; Cohen, Pinchas; Kannan, Ram; Hinton, David R

    2016-01-01

    Humanin (HN) is a small mitochondrial-encoded peptide with neuroprotective properties. We have recently shown protection of retinal pigmented epithelium (RPE) cells by HN in oxidative stress; however, the effect of HN on endoplasmic reticulum (ER) stress has not been evaluated in any cell type. Our aim here was to study the effect of HN on ER stress-induced apoptosis in RPE cells with a specific focus on ER-mitochondrial cross-talk. Dose dependent effects of ER stressors (tunicamycin (TM), brefeldin A, and thapsigargin) were studied after 12 hr of treatment in confluent primary human RPE cells with or without 12 hr of HN pretreatment (1-20 μg/mL). All three ER stressors induced RPE cell apoptosis in a dose dependent manner. HN pretreatment significantly decreased the number of apoptotic cells with all three ER stressors in a dose dependent manner. HN pretreatment similarly protected U-251 glioma cells from TM-induced apoptosis in a dose dependent manner. HN pretreatment significantly attenuated activation of caspase 3 and ER stress-specific caspase 4 induced by TM. TM treatment increased mitochondrial superoxide production, and HN co-treatment resulted in a decrease in mitochondrial superoxide compared to TM treatment alone. We further showed that depleted mitochondrial glutathione (GSH) levels induced by TM were restored with HN co-treatment. No significant changes were found for the expression of several antioxidant enzymes between TM and TM plus HN groups except for the expression of glutamylcysteine ligase catalytic subunit (GCLC), the rate limiting enzyme required for GSH biosynthesis, which is upregulated with TM and TM+HN treatment. These results demonstrate that ER stress promotes mitochondrial alterations in RPE that lead to apoptosis. We further show that HN has a protective effect against ER stress-induced apoptosis by restoring mitochondrial GSH. Thus, HN should be further evaluated for its therapeutic potential in disorders linked to ER stress.

  14. Skin-Derived Precursors against UVB-Induced Apoptosis via Bcl-2 and Nrf2 Upregulation

    PubMed Central

    Zhong, Jianqiao

    2016-01-01

    Bcl-2 and Nrf2 are critical factors in protecting cells against UVB-induced apoptosis. Hair-follicle-bulge stem cells could resist ionization through Bcl-2 upregulation. Skin-derived precursors (SKPs) dwelling on the bulge may be against UVB irradiation. Initially, SKPs were isolated and identified. Then, SKPs were exposed to UVB and grew in medium for 24 hours. CCK-8 assay, TUNEL, and Ki67 staining evaluated cells apoptosis/proliferation, while SA-βgal staining evaluated cells senescence and pH2AX immunostaining evaluated DNA damage. Meanwhile, Bcl-2, Nrf2, HO-1, Bax, and Bak expressions were assessed by qRT-PCR and western blot. Two weeks later, floating spheres appeared and were identified as SKPs. After UVB radiation, SKPs maintained spherical colonies and outnumbered unirradiated ones, showing high Ki67 expression and low TUNEL, SA-βgal, and pH2AX expression. Fibroblasts (FBs), however, displayed deformation, senescence, and reduction, with increased TUNEL, SA-βgal, and pH2AX expression. Moreover, Bcl-2 and Nrf2 mRNA expression were significantly higher than Bak and Bax in irradiated SKPs. Conversely, Bcl-2 and Nrf2 mRNA levels greatly decreased compared with Bax and Bak in irradiated FBs. Interestingly, SKPs showed higher protein levels of Bcl-2, Nrf2, and HO-1 than FBs. SKPs exert a beneficial effect on resisting UVB-induced apoptosis, which may be associated with Bcl-2 and Nrf2 upregulation. PMID:27635399

  15. Functional Role of Suppressor of Cytokine Signaling 3 Upregulation in Hypothalamic Leptin Resistance and Long-Term Energy Homeostasis

    PubMed Central

    Reed, Alison S.; Unger, Elizabeth K.; Olofsson, Louise E.; Piper, Merisa L.; Myers, Martin G.; Xu, Allison W.

    2010-01-01

    OBJECTIVE Hypothalamic leptin resistance is found in most common forms of obesity, such as diet-induced obesity, and is associated with increased expression of suppressor of cytokine signaling 3 (Socs3) in the hypothalamus of diet-induced obese animals. This study aims to determine the functional consequence of Socs3 upregulation on leptin signaling and obesity, and to investigate whether Socs3 upregulation affects energy balance in a cell type–specific way. RESEARCH DESIGN AND METHODS We generated transgenic mice overexpressing Socs3 in either proopiomelanocortin (POMC) or leptin receptor–expressing neurons, at levels similar to what is observed in diet-induced obesity. RESULTS Upregulation of Socs3 in POMC neurons leads to impairment of STAT3 and mammalian target of rapamycin (mTOR)–S6K-S6 signaling, with subsequent leptin resistance, obesity, and glucose intolerance. Unexpectedly, Socs3 upregulation in leptin receptor neurons results in increased expression of STAT3 protein in mutant hypothalami, but does not lead to obesity. CONCLUSIONS Our study establishes that Socs3 upregulation alone in POMC neurons is sufficient to cause leptin resistance and obesity. Socs3 upregulation impairs both STAT3 and mTOR signaling before the onset of obesity. The lack of obesity in mice with upregulated Socs3 in leptin receptor neurons suggests that Socs3's effect on energy balance could be cell type specific. Our study indicates that POMC neurons are important mediators of Socs3's effect on leptin resistance and obesity, but that other cell types or alteration of other signaling regulators could contribute to the development of obesity. PMID:20068134

  16. Detrimental Effects of Diet-Induced Obesity on τ Pathology Are Independent of Insulin Resistance in τ Transgenic Mice

    PubMed Central

    Leboucher, Antoine; Laurent, Cyril; Fernandez-Gomez, Francisco-José; Burnouf, Sylvie; Troquier, Laetitia; Eddarkaoui, Sabiha; Demeyer, Dominique; Caillierez, Raphaëlle; Zommer, Nadège; Vallez, Emmanuelle; Bantubungi, Kadiombo; Breton, Christophe; Pigny, Pascal; Buée-Scherrer, Valérie; Staels, Bart; Hamdane, Malika; Tailleux, Anne; Buée, Luc; Blum, David

    2013-01-01

    The τ pathology found in Alzheimer disease (AD) is crucial in cognitive decline. Midlife development of obesity, a major risk factor of insulin resistance and type 2 diabetes, increases the risk of dementia and AD later in life. The impact of obesity on AD risk has been suggested to be related to central insulin resistance, secondary to peripheral insulin resistance. The effects of diet-induced obesity (DIO) on τ pathology remain unknown. In this study, we evaluated effects of a high-fat diet, given at an early pathological stage, in the THY-Tau22 transgenic mouse model of progressive AD-like τ pathology. We found that early and progressive obesity potentiated spatial learning deficits as well as hippocampal τ pathology at a later stage. Surprisingly, THY-Tau22 mice did not exhibit peripheral insulin resistance. Further, pathological worsening occurred while hippocampal insulin signaling was upregulated. Together, our data demonstrate that DIO worsens τ phosphorylation and learning abilities in τ transgenic mice independently from peripheral/central insulin resistance. PMID:23250356

  17. MLN4924 induces Noxa upregulation in acute myelogenous leukemia and synergizes with Bcl-2 inhibitors.

    PubMed

    Knorr, K L B; Schneider, P A; Meng, X W; Dai, H; Smith, B D; Hess, A D; Karp, J E; Kaufmann, S H

    2015-12-01

    MLN4924 (pevonedistat), an inhibitor of the Nedd8 activating enzyme (NAE), has exhibited promising clinical activity in acute myelogenous leukemia (AML). Here we demonstrate that MLN4924 induces apoptosis in AML cell lines and clinical samples via a mechanism distinct from those observed in other malignancies. Inactivation of E3 cullin ring ligases (CRLs) through NAE inhibition causes accumulation of the CRL substrate c-Myc, which transactivates the PMAIP1 gene encoding Noxa, leading to increased Noxa protein, Bax and Bak activation, and subsequent apoptotic changes. Importantly, c-Myc knockdown diminishes Noxa induction; and Noxa siRNA diminishes MLN4924-induced killing. Because Noxa also neutralizes Mcl-1, an anti-apoptotic Bcl-2 paralog often upregulated in resistant AML, further experiments have examined the effect of combining MLN4924 with BH3 mimetics that target other anti-apoptotic proteins. In combination with ABT-199 or ABT-263 (navitoclax), MLN4924 exerts a synergistic cytotoxic effect. Collectively, these results provide new insight into MLN4924-induced engagement of the apoptotic machinery that could help guide further exploration of MLN4924 for AML.

  18. Epigenetic Upregulation of Corticotrophin-Releasing Hormone Mediates Postnatal Maternal Separation-Induced Memory Deficiency

    PubMed Central

    Wang, Aiyun; Nie, Wenying; Li, Haixia; Hou, Yuhua; Yu, Zhen; Fan, Qing; Sun, Ruopeng

    2014-01-01

    Accumulating evidences demonstrated that early postnatal maternal separation induced remarkable social and memory defects in the adult rodents. Early-life stress induced long-lasting functional adaptation of neuroendocrine hypothalamic-pituitary-adrenal axis, including neuropeptide corticotrophin-releasing hormone (CRH) in the brain. In the present study, a significantly increased hippocampal CRH was observed in the adult rats with postnatal maternal separation, and blockade of CRHR1 signaling significantly attenuated the hippocampal synaptic dysfunction and memory defects in the modeled rats. Postnatal maternal separation enduringly increased histone H3 acetylation and decreased cytosine methylation in Crh promoter region, resulting from the functional adaptation of several transcriptional factors, in the hippocampal CA1 of the modeled rats. Enriched environment reversed the epigenetic upregulation of CRH, and ameliorated the hippocampal synaptic dysfunction and memory defects in the adult rats with postnatal maternal separation. This study provided novel insights into the epigenetic mechanism underlying postnatal maternal separation-induced memory deficiency, and suggested environment enrichment as a potential approach for the treatment of this disorder. PMID:24718660

  19. Chronic administration of recombinant IL-6 upregulates lipogenic enzyme expression and aggravates high-fat-diet-induced steatosis in IL-6-deficient mice.

    PubMed

    Vida, Margarita; Gavito, Ana Luisa; Pavón, Francisco Javier; Bautista, Dolores; Serrano, Antonia; Suarez, Juan; Arrabal, Sergio; Decara, Juan; Romero-Cuevas, Miguel; Rodríguez de Fonseca, Fernando; Baixeras, Elena

    2015-07-01

    Interleukin-6 (IL-6) has emerged as an important mediator of fatty acid metabolism with paradoxical effects in the liver. Administration of IL-6 has been reported to confer protection against steatosis, but plasma and tissue IL-6 concentrations are elevated in chronic liver diseases, including fatty liver diseases associated with obesity and alcoholic ingestion. In this study, we further investigated the role of IL-6 on steatosis induced through a high-fat diet (HFD) in wild-type (WT) and IL-6-deficient (IL-6(-/-)) mice. Additionally, HFD-fed IL-6(-/-) mice were also chronically treated with recombinant IL-6 (rIL-6). Obesity in WT mice fed a HFD associated with elevated serum IL-6 levels, fatty liver, upregulation of carnitine palmitoyltransferase 1 (CPT1) and signal transducer and activator of transcription-3 (STAT3), increased AMP kinase phosphorylation (p-AMPK), and downregulation of the hepatic lipogenic enzymes fatty acid synthase (FAS) and stearoyl-CoA desaturase 1 (SCD1). The HFD-fed IL-6(-/-) mice showed severe steatosis, no changes in CPT1 levels or AMPK activity, no increase in STAT3 amounts, inactivated STAT3, and marked downregulation of the expression of acetyl-CoA carboxylase (ACCα/β), FAS and SCD1. The IL-6 chronic replacement in HFD-fed IL-6 -/-: mice restored hepatic STAT3 and AMPK activation but also increased the expression of the lipogenic enzymes ACCα/β, FAS and SCD1. Furthermore, rIL-6 administration was associated with aggravated steatosis and elevated fat content in the liver. We conclude that, in the context of HFD-induced obesity, the administration of rIL-6 might contribute to the aggravation of fatty liver disease through increasing lipogenesis.

  20. Chronic administration of recombinant IL-6 upregulates lipogenic enzyme expression and aggravates high-fat-diet-induced steatosis in IL-6-deficient mice

    PubMed Central

    Vida, Margarita; Gavito, Ana Luisa; Pavón, Francisco Javier; Bautista, Dolores; Serrano, Antonia; Suarez, Juan; Arrabal, Sergio; Decara, Juan; Romero-Cuevas, Miguel; Rodríguez de Fonseca, Fernando; Baixeras, Elena

    2015-01-01

    ABSTRACT Interleukin-6 (IL-6) has emerged as an important mediator of fatty acid metabolism with paradoxical effects in the liver. Administration of IL-6 has been reported to confer protection against steatosis, but plasma and tissue IL-6 concentrations are elevated in chronic liver diseases, including fatty liver diseases associated with obesity and alcoholic ingestion. In this study, we further investigated the role of IL-6 on steatosis induced through a high-fat diet (HFD) in wild-type (WT) and IL-6-deficient (IL-6−/−) mice. Additionally, HFD-fed IL-6−/− mice were also chronically treated with recombinant IL-6 (rIL-6). Obesity in WT mice fed a HFD associated with elevated serum IL-6 levels, fatty liver, upregulation of carnitine palmitoyltransferase 1 (CPT1) and signal transducer and activator of transcription-3 (STAT3), increased AMP kinase phosphorylation (p-AMPK), and downregulation of the hepatic lipogenic enzymes fatty acid synthase (FAS) and stearoyl-CoA desaturase 1 (SCD1). The HFD-fed IL-6−/− mice showed severe steatosis, no changes in CPT1 levels or AMPK activity, no increase in STAT3 amounts, inactivated STAT3, and marked downregulation of the expression of acetyl-CoA carboxylase (ACCα/β), FAS and SCD1. The IL-6 chronic replacement in HFD-fed IL-6−/− mice restored hepatic STAT3 and AMPK activation but also increased the expression of the lipogenic enzymes ACCα/β, FAS and SCD1. Furthermore, rIL-6 administration was associated with aggravated steatosis and elevated fat content in the liver. We conclude that, in the context of HFD-induced obesity, the administration of rIL-6 might contribute to the aggravation of fatty liver disease through increasing lipogenesis. PMID:26035386

  1. Arterial stiffening precedes systolic hypertension in diet-induced obesity.

    PubMed

    Weisbrod, Robert M; Shiang, Tina; Al Sayah, Leona; Fry, Jessica L; Bajpai, Saumendra; Reinhart-King, Cynthia A; Lob, Heinrich E; Santhanam, Lakshmi; Mitchell, Gary; Cohen, Richard A; Seta, Francesca

    2013-12-01

    Stiffening of conduit arteries is a risk factor for cardiovascular morbidity. Aortic wall stiffening increases pulsatile hemodynamic forces that are detrimental to the microcirculation in highly perfused organs, such as the heart, brain, and kidney. Arterial stiffness is associated with hypertension but presumed to be due to an adaptive response to increased hemodynamic load. In contrast, a recent clinical study found that stiffness precedes and may contribute to the development of hypertension although the mechanisms underlying hypertension are unknown. Here, we report that in a diet-induced model of obesity, arterial stiffness, measured in vivo, develops within 1 month of the initiation of the diet and precedes the development of hypertension by 5 months. Diet-induced obese mice recapitulate the metabolic syndrome and are characterized by inflammation in visceral fat and aorta. Normalization of the metabolic state by weight loss resulted in return of arterial stiffness and blood pressure to normal. Our findings support the hypothesis that arterial stiffness is a cause rather than a consequence of hypertension.

  2. Arginase inhibition restores endothelial function in diet-induced obesity.

    PubMed

    Chung, Ji Hyung; Moon, Jiyoung; Lee, Youn Sue; Chung, Hye-Kyung; Lee, Seung-Min; Shin, Min-Jeong

    2014-08-22

    Arginase may play a major role in the regulation of vascular function in various cardiovascular disorders by impairing nitric oxide (NO) production. In the current study, we investigated whether supplementation of the arginase inhibitor N(ω)-hydroxy-nor-l-arginine (nor-NOHA) could restore endothelial function in an animal model of diet-induced obesity. Arginase 1 expression was significantly lower in the aorta of C57BL/6J mice fed a high-fat diet (HFD) supplemented with nor-NOHA (40mgkg(-1)/day) than in mice fed HFD without nor-NOHA. Arginase inhibition led to considerable increases in eNOS expression and NO levels and significant decreases in the levels of circulating ICAM-1. These findings were further confirmed by the results of siRNA-mediated knockdown of Arg in human umbilical vein endothelial cells. In conclusion, arginase inhibition can help restore dysregulated endothelial function by increasing the eNOS-dependent NO production in the endothelium, indicating that arginase could be a therapeutic target for correcting obesity-induced vascular endothelial dysfunction.

  3. Piperine’s mitigation of obesity and diabetes can be explained by its up-regulation of the metabolic rate of resting muscle

    PubMed Central

    Naber, Nariman; Pate, Edward; Canton, Marcella; Reggiani, Carlo; Cooke, Roger

    2016-01-01

    We identify a target for treating obesity and type 2 diabetes, the consumption of calories by an increase in the metabolic rate of resting skeletal muscle. The metabolic rate of skeletal muscle can be increased by shifting myosin heads from the super-relaxed state (SRX), with a low ATPase activity, to a disordered relaxed state (DRX), with a higher ATPase activity. The shift of myosin heads was detected by a change in fluorescent intensity of a probe attached to the myosin regulatory light chain in skinned skeletal fibers, allowing us to perform a high-throughput screen of 2,128 compounds. The screen identified one compound, which destabilized the super-relaxed state, piperine (the main alkaloid component of black pepper). Destabilization of the SRX by piperine was confirmed by single-nucleotide turnover measurements. The effect was only observed in fast twitch skeletal fibers and not in slow twitch fibers or cardiac tissues. Piperine increased ATPase activity of skinned relaxed fibers by 66 ± 15%. The Kd was ∼2 µM. Piperine had little effect on the mechanics of either fully active or resting muscle fibers. Previous work has shown that piperine can mitigate both obesity and type 2 diabetes in rodent models of these conditions. We propose that the increase in resting muscle metabolism contributes to these positive effects. The results described here show that up-regulation of resting muscle metabolism could treat obesity and type 2 diabetes and that piperine would provide a useful lead compound for the development of these therapies. PMID:27799519

  4. Areca nut extract induced oxidative stress and upregulated hypoxia inducing factor leading to autophagy in oral cancer cells.

    PubMed

    Lu, Hsuan-Hsuan; Kao, Shou-Yen; Liu, Tsung-Yun; Liu, Shou-Tien; Huang, Wei-Pang; Chang, Kuo-Wei; Lin, Shu-Chun

    2010-08-01

    Areca (betel) chewing was tightly linked to oral tumorigenesis in Asians. Areca nut was a recently confirmed group I carcinogen and a popular addictive substance used by Asians. Meanwhile, the pathogenetic impact of areca on oral epithelial cells was still unclear. This study investigated the association between the induction of autophagy by areca nut extract (ANE) and the molecular regulation underlying this induction in oral cancer cells. Oral cancer cells were treated with ANE to incite the signaling changes underlying phenotypic alterations. The NFkappaB activation and reactive oxygen species (ROS) genesis were induced by ANE and the NFkappaB activation could be the basis of the ROS genesis. Furthermore, p38 activation and upregulation of MKP-1 phosphatase occurred following ANE treatment. These effects can be inhibited by ROS blockers. ANE treatment induced autophagy among oral cancer cells, which was characterized by LC3-II accumulation, genesis of autophagosomes and the appearance of EGFP-LC3 puncta. This induction was mediated through the activation of p38, MKP-1 and HIF-1alpha. Knockdown of ANE-modulated HIF-1alpha expression reduced autophagy. Blockage of ANE-induced autophagy increased the proportion of oral cancer cells undergoing apoptotic death. This study identified for the first time that ANE modulates a signaling cascade that induces HIF-1alpha expression in oral cancer cells. The eventual induction of autophagy was beneficial to cell survival from ANE-induced apoptosis.

  5. Hypoxia-inducible factor-1alpha signaling in aquaporin upregulation after traumatic brain injury.

    PubMed

    Ding, Jamie Y; Kreipke, Christian W; Speirs, Susan L; Schafer, Patrick; Schafer, Steven; Rafols, José A

    2009-03-27

    Previous studies have demonstrated that traumatic brain injury (TBI) causes brain edema via aquaporins (AQPs), the water-transporting proteins. In the present study, we determined the role of hypoxia inducible factor-1alpha (HIF-1alpha), which is a transcription factor in response to physiological hypoxia, in regulating expression of AQP4 and AQP9. Adult male Sprague-Dawley rats (400-425g) received a closed head injury using the Marmarou weight drop model with a 450g weight and survived for 1, 4, 24 and 48h. Some animals were administered 30min after injury with 2-methoxyestradiol (2ME2), a naturally occurring metabolite of estradiol which is known to post-transcriptionally down-regulate HIF-1alpha expression, and sacrificed 4h after injury. Real-time PCR and Western blot were used, respectively, to detect gene and protein expressions of manganese superoxide dismutase (MnSOD, showing hypoxic stress), HIF-1alpha, AQP4, and AQP9. ANOVA analysis demonstrated a significant (p<0.05) increase in gene expression of MnSOD, HIF-1alpha, AQP4, and AQP9, starting at 1h after injury through 48h. Western blot analysis further indicated a significant (p<0.05) increase in protein expression of these molecules at the same time points. Pharmacological inhibition of HIF-1alpha by 2ME2 reduced the up-regulated levels of AQP4 and AQP9 after TBI. The present study suggests that hypoxic conditions determined by MnSOD expression after closed head injury contribute to HIF-1alpha expression. HIF-1alpha, in turn, up-regulates expression of AQP4 and AQP9. These results characterize the pathophysiological mechanisms, and suggest possible therapeutic targets for TBI patients.

  6. Hypoxia-Inducible Factor-1α Signaling in Aquaporin Upregulation After Traumatic Brain Injury

    PubMed Central

    Ding, Jamie Y.; Kreipke, Christian W.; Speirs, Susan L.; Schafer, Patrick; Schafer, Steven; Rafols, José A.

    2009-01-01

    Previous studies have demonstrated that traumatic brain injury (TBI) causes brain edema via aquaporins (AQPs), the water transporting proteins. In the present study, we determined the role of hypoxia inducible factor-1α (HIF-1α), which is a transcription factor in response to physiological hypoxia, in regulating expression of AQP4 and AQP9. Adult male Sprague-Dawley rats (400–425g) received a closed head injury using the Marmarou weight drop model with a 450 g weight and survived for 1, 4, 24 and 48 hours. Some animals were administered 30 minutes after injury with 2-Methoxyestradiol (2ME2), a naturally occurring metabolite of estradiol which is known to post-transcriptionally down-regulate HIF-1α expression, and sacrificed 4 hours after injury. Real-time PCR and Western blot were used, respectively, to detect gene and protein expressions of manganese superoxide dismutase (MnSOD, showing hypoxic stress), HIF-1α, AQP4, and AQP9. ANOVA analysis demonstrated a significant (p<0.05) increase in gene expression of MnSOD, HIF-1α, AQP4, and AQP9, starting at 1 hour after injury through 48 hours. Western blot analysis further indicated a significant (p<0.05) increase in protein expression of these molecules at the same time points. Pharmacological inhibition of HIF-1α by 2ME2 reduced the up-regulated levels of AQP4 and AQP9 after TBI. The present study suggests that hypoxic conditions determined by MnSOD expression after closed head injury contribute to HIF-1α expression. HIF-1α, in turn, up-regulates expression of AQP4 and AQP9. These results characterize the pathophysiological mechanisms, and suggest possible therapeutic targets for TBI patients. PMID:19429018

  7. The Effects of Metformin on Obesity-Induced Dysfunctional Retinas

    PubMed Central

    Kim, Andy Jeesu; Chang, Janet Ya-An; Shi, Liheng; Chang, Richard Cheng-An; Ko, Michael Lee; Ko, Gladys Yi-Ping

    2017-01-01

    Purpose The purpose of this study was to determine the effects of metformin on dysfunctional retinas in obesity-induced type 2 diabetic mice. Methods A high-fat diet (HFD)-induced diabetic mouse model (C57BL/6J) was used in this study. After 2 months of the HFD regimen, HFD mice were given daily metformin through oral gavage. Body weights, glucose tolerance, and retinal light responses were monitored regularly. Fluorescein angiography (FA) was used to assess changes in retinal vasculature. Ocular tissues (retina, vitreous, and lens) were harvested and analyzed for molecular changes as determined by immunofluorescent staining, Western blot analysis, and cytokine profiling. Results Starting 1 month after the diet regimen, mice fed the HFD had mildly compromised retinal light responses as measured by electroretinography (ERG), which worsened over time compared to that in the control. In HFD mice treated with metformin, systemic glucose levels reverted back to normal, and their weight gain slowed. Metformin reversed HFD-induced changes in phosphorylated protein kinase B (pAKT), extracellular signal-regulated kinase (pERK), and 5′AMP-activated protein kinase (pAMPK) in the retina. However, metformin treatments for 3 months did not restore the retinal light responses nor lessen the HFD-induced retinal neovascularization, even though it did reduce intraocular inflammation. Conclusions Although metformin was able to reverse systemic changes induced by HFD, it was not able to restore HFD-caused retinal light responses or deter neovascularization. PMID:28114566

  8. Upregulation of miR-137 protects anesthesia-induced hippocampal neurodegeneration

    PubMed Central

    Huang, Changshun; Zhang, Xingcai; Zheng, Jungang; Chen, Chunru; Chen, Yijun; Yi, Juan

    2014-01-01

    Purpose: Ketamine is commonly used in pediatric anesthesia but may cause neurodegeneration in young brains. The aim of the study is to use an animal model to characterize the role of microRNA 137 (miR-137) in ketamine-induced neurodegeneration in neonatal hippocampus. Methods: Young Sprague-Dawley Rats (1 month old) was systemically administrated with ketamine (75 mg/kg) for 3 days. TUNEL assay was used to assess the ketamine-induced neurodegeneration of hippocampal CA1 neurons, quantitative real-time PCR (qRT-PCR) to assess the expression of miR-137 and Morris water maze test (MWM) to assess the damaged memory function. Alternatively, lentivirus over-expressing miR-137 was injected into hippocampus before ketamine administration, and the subsequent effects of miR-137 upregulation on ketamine-induced hippocampal neurodegeneration and memory dysfunction were investigated. Furthermore, the direct downstream target of miR-137, CDC42, was down-regulated by siRNA injection into hippocampus. The effects of CDC42 inhibition on hippocampal apoptosis and memory function were also investigated. Results: Excessive ketamine treatment resulted in severe apoptosis in hippocampal CA1 neurons, downregulation of miR-137 in hippocampus and significant long-term memory dysfunction. Conversely, pre-treatment of overexpressing miR-137 protected hippocampal neurodegeneration and memory loss. The molecular target of miR-137, CDC42 was down-regulated by ketamine in hippocampus. Knocking down hippocampal CDC42 exerted an apoptotic effect on hippocampal neurons and memory loss, similar to the effect of ketamine treatment. Conclusions: Our results demonstrated that miR-137 played an important role in regulating ketamine induced hippocampal neurodegeneration, possibly through CDC42. PMID:25197371

  9. Up-regulation of inducible heat shock protein-70 expression in multiple sclerosis patients.

    PubMed

    Mansilla, María José; Comabella, Manuel; Río, Jordi; Castilló, Joaquín; Castillo, Mireia; Martin, Roland; Montalban, Xavier; Espejo, Carmen

    2014-03-01

    Inducible heat shock protein (HSP)70 (HSP70-1A and HSP70-1B proteins) is a chaperone responsible for assisting proper protein folding. Following stress conditions, HSP70 is highly up-regulated to mediate cytoprotective functions. In addition, HSP70 is able to trigger innate and adaptive immune responses that promote the immune recognition of antigens and to act as a cytokine when it is released. The data in the literature are controversial with regard to expression studies in peripheral blood mononuclear cells (PBMCs). In the present study, we aimed to examine if alterations of HSP70-1A/B expression are involved in the autoimmune pathogenesis of multiple sclerosis (MS). We determined both mRNA and protein expression in PBMCs of MS patients and healthy donors (HDs). We found a baseline increased expression of the HSPA1A gene in PBMCs from MS patients compared with HDs. Gene expression findings were associated with an increased protein expression of HSP70-1A/B in T lymphocytes (CD4+ and CD8+) and monocytes from MS patients under basal conditions that may reflect the immunological activation occurring in MS patients. We also provided evidence that heat shock (HS) stimulus induced HSP70-1A/B protein expression in HDs and MS patients, and that HS-induced HSP70-1A/B protein expression in monocytes correlated with the number of T2 lesions at baseline in MS patients. However, after lipopolysaccharide inflammatory stimulus, monocytes from MS patients failed to induce HSP70-1A/B protein expression. Our data hint at altered immune responses in MS and may indicate either a state of chronic stress or increased vulnerability to physiological immune responses in MS patients.

  10. Hypergravity upregulates renal inducible nitric oxide synthase expression and nitric oxide production

    PubMed Central

    Yoon, Gun; Oh, Choong Sik; Kim, Hyun-Soo

    2016-01-01

    Exposure to hypergravity severely decreases renal blood flow, potentially causing renal dysfunction. Nitric oxide (NO), which is endogenously synthesized by inducible NO synthase (iNOS), plays an important role in the regulation of renal function. The purpose of this study was to examine the effect of hypergravity exposure on the production of NO in kidneys. To determine whether hypergravity induces renal hypoxia and alters renal iNOS expression and NO production, mice were exposed to short-term hypergravity at +3Gz for 1 h. The time course of iNOS mRNA expression, hypoxia-inducible factor (HIF)-1α expression, and NO production was examined. Renal HIF-1α levels were significantly elevated immediately after centrifugation, and this increase was sustained for 3 h post-exposure. iNOS mRNA levels were also significantly increased immediately after exposure and were maintained during the reoxygenation period. Immunohistochemical staining for iNOS revealed that the cortical tubular epithelium exhibited moderate to strong cytoplasmic iNOS immunoreactivity immediately after hypergravity exposure and during the reoxygenation period. The time course of NO production was similar to that of iNOS expression. Our results suggest that both hypoxia and reoxygenation might be involved in the upregulation of HIF-1α in the kidneys of mice exposed to hypergravity. Significant increases in renocortical iNOS expression immediately after centrifugation and during the reoxygenation period suggest that iNOS expression induced by hypergravity exposure might play a protective role against hypoxia/reoxygenation injury in the renal cortex. Further investigations are necessary to clarify the role of iNOS and NO in kidneys exposed to hypergravity. PMID:27174912

  11. Anti-obesity effect of Triticum aestivum sprout extract in high-fat-diet-induced obese mice.

    PubMed

    Im, Ji-Young; Ki, Hyeon-Hui; Xin, Mingjie; Kwon, Se-Uk; Kim, Young Ho; Kim, Dae-Ki; Hong, Sun-Pyo; Jin, Jong-Sik; Lee, Young-Mi

    2015-01-01

    Obesity is a common disease worldwide that often results in serious conditions including hypertension, diabetes, and hyperlipidemia. Many herbal medicines have been examined with regard to ameliorating obesity. We investigated the anti-obesity effects of 50% EtOH extract of Triticum aestivum sprout (TAEE) in high-fat-diet (HFD)-induced obese mice. TAEE administration (10, 50, or 200 mg/kg) for 6 weeks significantly decreased the body weights, serum total cholesterol (TC), and low-density lipoprotein cholesterol levels in HFD-fed mice. TAEE treatment reduced lipid accumulation in epididymal white adipose tissue (EWAT) and liver. Moreover, TC and lipid levels were decreased by TAEE treatment in liver. Serum leptin and adiponectin concentrations were reduced by TAEE treatment. TAEE-treated mice showed decreases in peroxisome proliferator-activated receptor γ (PPARγ) and fatty acid synthase expression in EWAT. Furthermore, TAEE administration elevated levels of PPARα protein in the liver of HFD-induced obese mice. These results suggest that TAEE supplementation might be beneficial for the treatment and prevention of obesity and related diseases.

  12. Anti-Obesity Effects of Aster spathulifolius Extract in High-Fat Diet-Induced Obese Rats.

    PubMed

    Kim, Sa-Jic; Bang, Chae-Young; Guo, Yuan-Ri; Choung, Se-Young

    2016-04-01

    The aim of this study was to investigate the anti-obesity and antihyperlipidemic efficacy and molecular mechanisms of Aster spathulifolius Maxim extract (ASE) in rats with high-fat diet (HFD)-induced obesity. Rats were separately fed a normal diet or a HFD for 8 weeks, then they were treated with ASE (62.5, 125, or 250 mg/kg) for another 4.5 weeks. The ASE supplementation significantly lowered body weight gain, visceral fat pad weights, serum lipid levels, as well as hepatic lipid levels in HFD-induced obese rats. Histological analysis showed that the ASE-treated group showed lowered numbers of lipid droplets and smaller size of adipocytes compared to the HFD group. To understand the mechanism of action of ASE, the expression of genes and proteins involved in obesity were measured in liver and skeletal muscle. The expression of fatty acid oxidation and thermogenesis-related genes (e.g., PPAR-α, ACO, CPT1, UCP2, and UCP3) of HFD-induced obese rats were increased by ASE treatment. On the other hand, ASE treatment resulted in decreased expression of fat intake-related gene ACC2 and lipogenesis-related genes (e.g., SREBP-1c, ACC1, FAS, SCD1, GPATR, AGPAT, and DGAT). Furthermore, ASE treatment increased the level of phosphorylated AMPKα in obese rats. Similarly, the level of phosphorylated ACC, a target protein of AMPKα in ASE groups, was increased by ASE treatment compared with the HFD group. These results suggest that ASE attenuated visceral fat accumulation and improved hyperlipidemia in HFD-induced obese rats by increasing lipid metabolism through the regulation of AMPK activity and the expression of genes and proteins involved in lipolysis and lipogenesis.

  13. Hypoxia Induces Autophagy through Translational Up-Regulation of Lysosomal Proteins in Human Colon Cancer Cells

    PubMed Central

    Lai, Ming-Chih; Chang, Chiao-May; Sun, H. Sunny

    2016-01-01

    Hypoxia occurs in a wide variety of physiological and pathological conditions, including tumorigenesis. Tumor cells have to adapt to hypoxia by altering their gene expression and protein synthesis. Here, we showed that hypoxia inhibits translation through activation of PERK and inactivation of mTOR in human colon cancer HCT116 cells. Prolonged hypoxia (1% O2, 16 h) dramatically inhibits general translation in HCT116 cells, yet selected mRNAs remain efficiently translated under such a condition. Using microarray analysis of polysome- associated mRNAs, we identified a large number of hypoxia-regulated genes at the translational level. Efficiently translated mRNAs during hypoxia were validated by polysome profiling and quantitative real-time RT-PCR. Pathway enrichment analysis showed that many of the up-regulated genes are involved in lysosome, glycan and lipid metabolism, antigen presentation, cell adhesion, and remodeling of the extracellular matrix and cytoskeleton. The majority of down-regulated genes are involved in apoptosis, ubiquitin-mediated proteolysis, and oxidative phosphorylation. Further investigation showed that hypoxia induces lysosomal autophagy and mitochondrial dysfunction through translational regulation in HCT116 cells. The abundance of several translation factors and the mTOR kinase activity are involved in hypoxia-induced mitochondrial autophagy in HCT116 cells. Our studies highlight the importance of translational regulation for tumor cell adaptation to hypoxia. PMID:27078027

  14. The role of vitamin D3 upregulated protein 1 in thioacetamide-induced mouse hepatotoxicity

    SciTech Connect

    Kwon, Hyo-Jung; Lim, Jong-Hwan; Han, Jong-Tak; Lee, Sae-Bhom; Yoon, Won-Kee; Nam, Ki-Hoan; Choi, In-Pyo; Kim, Dae-Yong; Won, Young-Suk; Kim, Hyoung-Chin

    2010-11-01

    Thioacetamide (TA) is a commonly used drug that can trigger acute hepatic failure (AHF) through generation of oxidative stress. Vitamin D3 upregulated protein 1 (VDUP1) is an endogenous inhibitor of thioredoxin, a ubiquitous thiol oxidoreductase, that regulates cellular redox status. In this study, we investigated the role of VDUP1 in AHF using a TA-induced liver injury model. VDUP1 knockout (KO) and wild-type (WT) mice were subjected to a single intraperitoneal TA injection, and various parameters of hepatic injury were assessed. VDUP1 KO mice displayed a significantly higher survival rate, lower serum alanine aminotransferase and aspartate aminotransferase levels, and less hepatic damage, compared to WT mice. In addition, induction of apoptosis was decreased in VDUP1 KO mice, with the alteration of caspase-3 and -9 activities, Bax-to-Bcl-2 expression ratios, and mitogen activated protein kinase (MAPK) signaling pathway. Importantly, analysis of TA bioactivation revealed lower plasma clearance of TA and covalent binding of [{sup 14}C]TA to liver macromolecules in VDUP1 KO mice. Furthermore, the level of oxidative stress was significantly less in VDUP1 KO mice than in their WT counterparts, as evident from lipid peroxidation assay. These results collectively indicate that VDUP1 deficiency protects against TA-induced acute liver injury via lower bioactivation of TA and antioxidant effects.

  15. Upregulation of Transient Receptor Potential Canonical Channels Contributes to Endotoxin-Induced Pulmonary Arterial Stenosis

    PubMed Central

    Chen, Gui-Lan; Jiang, Hongni; Zou, Fangdong

    2016-01-01

    Background Septic shock is a pathologic condition caused by endotoxin-producing bacteria, and often associated with severe pulmonary hypertension. Inflammation is a major systemic response to endotoxin; however, it is unknown whether endotoxin has a direct impact on pulmonary arteries that contributes to pathogenesis of pulmonary hypertension. Material/Methods Rat pulmonary arteries and primary pulmonary arterial smooth muscle cells (PASMCs) were cultured in vitro and treated with lipopolysaccharide (LPS) and blockers of transient receptor potential canonical (TRPC) channels. Neointimal growth and arterial stenosis were observed on cryosections of cultured pulmonary arteries. Proliferation of PASMCs was examined by a WST-1 (water-soluble tetrazolium salt) assay. Expression of TRPC genes in pulmonary arteries and PASMCs were detected and quantified by real-time polymerase chain reaction and Western blotting. Results LPS significantly induced neointimal growth and stenosis of pulmonary arteries and promoted proliferation of PASMCs. TRPC channel blockers 2-aminoethoxydiphenyl borate and SKF-96365 inhibited LPS-induced remodeling of pulmonary arteries and PASMC proliferation. Expression of TRPC1/3/4/6 was detected in pulmonary arteries and PASMCs. LPS treatment dramatically increased the expression of TRPC3 and TRPC4 at both messenger RNA and protein levels. Conclusions LPS stimulates stenosis of pulmonary arteries through enhancement of TRPC-mediated Ca2+ entry into PASMCs, which is caused by upregulation of TRPC3 and TRPC4 channels. PMID:27471122

  16. MicroRNA-203 induces apoptosis by upregulating Puma expression in colon and lung cancer cells.

    PubMed

    Funamizu, Naotake; Lacy, Curtis R; Kamada, Minori; Yanaga, Katsuhiko; Manome, Yoshinobu

    2015-11-01

    The present study investigated the relationship between microRNA-203 (miR-203) and the p53 upregulated modulator of apoptosis (Puma) in colon (HCT116) and lung cancer (A549) cells. Colon and lung cancer cell lines were selected for this study since a relationship between p53/miR-203 and p53/Puma has been established in both cancers. In the present study, adriamycin and nutlin-3 were used to activate p53, which induced both miR-203 and Puma expression in HCT116 cells. In contrast, HCT 116 cells with downregulated p53 showed decreased miR-203 and Puma expression. Importantly, we found that overexpressed miR-203 in HCT116 cells resulted in significantly increased Puma expression (P<0.05). Based on these findings, we hypothesized that another limb of the p53/Puma axis depends on miR-203 expression. To further validate this relationship, we used lung cancer cells (A549) and found that activated p53 increased both miR-203 and Puma expression. In addition, we found that Puma expression remained elevated in cells with overexpressed miR-203 in the presence of p53 downregulation. Cumulatively, our data purport that p53 not only increased Puma expression directly, but that it may also do so through miR-203. Additionally, functional studies revealed that miR-203 overexpression induced apoptosis and inhibited cell invasiveness.

  17. IRF-1 transcriptionally upregulates PUMA, which mediates the mitochondrial apoptotic pathway in IRF-1-induced apoptosis in cancer cells.

    PubMed

    Gao, J; Senthil, M; Ren, B; Yan, J; Xing, Q; Yu, J; Zhang, L; Yim, J H

    2010-04-01

    Interferon regulatory factor-1 (IRF-1) is a transcription factor that acts as a tumor suppressor and causes apoptosis in cancer cells. We evaluated IRF-1-induced apoptosis in gastric cancer cell lines. We established stable clones in AGS cells that have a tetracycline-inducible IRF-1 expression system. We used these clones and recombinant adenovirus expressing IRF-1 to explore the mechanism of IRF-1-induced apoptosis in gastric cancer. Expression of IRF-1 causes apoptosis in gastric cancer cell lines as shown by phosphatidylserine exposure and cleavage of caspase-8, caspase-3, and Bid with the mitochondrial release of cytochrome c. However, inhibition of caspase-8 and Bid did not inhibit apoptosis and did not decrease cleaved caspase-9 or mitochondrial release of cytochrome c. We then show that IRF-1 upregulates PUMA (p53 upregulated modulator of apoptosis), which is known to activate apoptosis by the intrinsic pathway; this can be p53-independent. IRF-1 binds to distinct sites in the promoter of PUMA and activates PUMA transcription. Moreover, molecular markers of mitochondrial apoptosis are eliminated in PUMA knockout and knockdown cells and phosphatidylserine exposure is decreased dramatically. Finally, we show that IFN-gamma induces IRF-1-mediated upregulation of PUMA in cancer cells. We conclude that IRF-1 can induce apoptosis by the intrinsic pathway independent of the extrinsic pathway by upregulation of PUMA.

  18. Leptin-Induced Endothelium-Dependent Vasorelaxation of Peripheral Arteries in Lean and Obese Rats: Role of Nitric Oxide and Hydrogen Sulfide

    PubMed Central

    Jamroz-Wiśniewska, Anna; Gertler, Arieh; Solomon, Gili; Wood, Mark E.; Whiteman, Matthew; Bełtowski, Jerzy

    2014-01-01

    Adipose tissue hormone leptin induces endothelium-dependent vasorelaxation mediated by nitric oxide (NO) and endothelium-derived hyperpolarizing factors (EDHF). Previously it has been demonstrated that in short-term obesity the NO-dependent and the EDHF-dependent components of vascular effect of leptin are impaired and up-regulated, respectively. Herein we examined the mechanism of the EDHF-dependent vasodilatory effect of leptin and tested the hypothesis that alterations of acute vascular effects of leptin in obesity are accounted for by chronic hyperleptinemia. The study was performed in 5 groups of rats: (1) control, (2) treated with exogenous leptin for 1 week to induce hyperleptinemia, (3) obese, fed highly-palatable diet for 4 weeks, (4) obese treated with pegylated superactive rat leptin receptor antagonist (PEG-SRLA) for 1 week, (5) fed standard chow and treated with PEG-SRLA. Acute effect of leptin on isometric tension of mesenteric artery segments was measured ex vivo. Leptin relaxed phenylephrine-preconstricted vascular segments in NO- and EDHF-dependent manner. The NO-dependent component was impaired and the EDHF-dependent component was increased in the leptin-treated and obese groups and in the latter group both these effects were abolished by PEG-SRLA. The EDHF-dependent vasodilatory effect of leptin was blocked by either the inhibitor of cystathionine γ-lyase, propargylglycine, or a hydrogen sulfide (H2S) scavenger, bismuth (III) subsalicylate. The results indicate that NO deficiency is compensated by the up-regulation of EDHF in obese rats and both effects are accounted for by chronic hyperleptinemia. The EDHF-dependent component of leptin-induced vasorelaxation is mediated, at least partially, by H2S. PMID:24475175

  19. Enzymatically synthesized glycogen reduces lipid accumulation in diet-induced obese rats.

    PubMed

    Furuyashiki, Takashi; Ogawa, Rui; Nakayama, Yoko; Honda, Kazuhisa; Kamisoyama, Hiroshi; Takata, Hiroki; Yasuda, Michiko; Kuriki, Takashi; Ashida, Hitoshi

    2013-09-01

    Based on a recent study indicating that enzymatically synthesized glycogen (ESG) possesses a dietary, fiber-like action, we hypothesized that ESG can reduce the risk of obesity. In this study, the antiobesity effects of ESG were investigated in a model of diet-induced obesity. Male Sprague-Dawley rats were divided into 4 groups and fed a normal or high-fat diet, with or without 20% ESG, for 4 weeks. Body weight, food intake, lipid deposition in the white adipose tissues and liver, fecal lipid excretion, and plasma lipid profiles were measured. At week 3, the body fat mass was measured using an x-ray computed tomography system, which showed that ESG significantly suppressed the high-fat diet-induced lipid accumulation. Similar results were observed in the weight of the adipose tissue after the experiment. Moreover, ESG significantly suppressed the lipid accumulation in the liver but increased fecal lipid excretion. The plasma concentrations of triacylglycerol and nonesterified fatty acid were lowered after a high-fat diet, whereas the total bile acid concentration was increased by ESG. However, the hepatic messenger RNA (mRNA) levels of enzymes related to lipid metabolism were not affected by ESG. Conversely, the mRNA levels of long-chain acyl-CoA dehydrogenase and medium-chain acyl-CoA dehydrogenase were up-regulated by ESG in the muscle. These results suggest that the combined effects of increased fecal lipid excretion, increased mRNA levels of enzymes that oxidize fatty acids in the muscle, and increased total bile acid concentration in the plasma mediate the inhibitory effect of ESG on lipid accumulation.

  20. Erythropoietin (EPO) ameliorates obesity and glucose homeostasis by promoting thermogenesis and endocrine function of classical brown adipose tissue (BAT) in diet-induced obese mice.

    PubMed

    Kodo, Kazuki; Sugimoto, Satoru; Nakajima, Hisakazu; Mori, Jun; Itoh, Ikuyo; Fukuhara, Shota; Shigehara, Keiichi; Nishikawa, Taichiro; Kosaka, Kitaro; Hosoi, Hajime

    2017-01-01

    Erythropoietin (EPO), clinically used as a hematopoietic drug, has received much attention due to its nonhematopoietic effects. EPO reportedly has beneficial effects on obesity and diabetes mellitus. We investigated whether interscapular brown adipose tissue (iBAT: main part of classical BAT) could play a role in EPO's anti-obesity and anti-diabetic effects in diet-induced obese mice. Four-week-old male C57BL/6J mice were fed a high-fat diet (HFD-Con), and half were additionally given an intraperitoneal injection of recombinant human EPO (200 IU/kg) (HFD-EPO) thrice a week for four weeks. At 8 weeks, EPO-injected mice showed significantly reduced body weight with reduced epididymal and subcutaneous white fat mass and unchanged caloric intake and locomotor activity. HOMA-IR (insulin resistance index) and glucose levels during intraperitoneal glucose tolerance test (IPGTT) were significantly lower in HFD-EPO mice than in HFD-Con mice. EPO-injected mice also showed increased oxygen consumption, indicative of metabolic rate, and skin temperature around iBAT tissue masses. EPO significantly upregulated the PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16), a transcriptional factor with a crucial role in brown adipocyte differentiation. EPO significantly increased phosphorylated signal transducer and activator of transcription 3 (STAT3), which is downstream of erythropoietin receptor (EpoR) and known to stabilize PRDM16. EPO's suppression of myocyte enhancer factor 2c (Mef2c) and microRNA-133a (miR-133a) via β3-adrenergic receptor caused PRDM16 upregulation. EPO-mediated enhancement of EpoR/STAT3 and β-adrenergic receptor/Mef2c/miR-133 pathways dramatically increases total uncoupling protein 1 (UCP1), an essential enzyme for BAT thermogenesis. Furthermore, EPO activated BAT's endocrine functions. EPO facilitated fibroblast growth factor 21 (FGF21) production and excretion in iBAT, associated with reduction of liver gluconeogenesis-related genes. Thus, EPO

  1. Erythropoietin (EPO) ameliorates obesity and glucose homeostasis by promoting thermogenesis and endocrine function of classical brown adipose tissue (BAT) in diet-induced obese mice

    PubMed Central

    Kodo, Kazuki; Sugimoto, Satoru; Mori, Jun; Itoh, Ikuyo; Fukuhara, Shota; Shigehara, Keiichi; Nishikawa, Taichiro; Kosaka, Kitaro; Hosoi, Hajime

    2017-01-01

    Erythropoietin (EPO), clinically used as a hematopoietic drug, has received much attention due to its nonhematopoietic effects. EPO reportedly has beneficial effects on obesity and diabetes mellitus. We investigated whether interscapular brown adipose tissue (iBAT: main part of classical BAT) could play a role in EPO’s anti-obesity and anti-diabetic effects in diet-induced obese mice. Four-week-old male C57BL/6J mice were fed a high-fat diet (HFD-Con), and half were additionally given an intraperitoneal injection of recombinant human EPO (200 IU/kg) (HFD-EPO) thrice a week for four weeks. At 8 weeks, EPO-injected mice showed significantly reduced body weight with reduced epididymal and subcutaneous white fat mass and unchanged caloric intake and locomotor activity. HOMA-IR (insulin resistance index) and glucose levels during intraperitoneal glucose tolerance test (IPGTT) were significantly lower in HFD-EPO mice than in HFD-Con mice. EPO-injected mice also showed increased oxygen consumption, indicative of metabolic rate, and skin temperature around iBAT tissue masses. EPO significantly upregulated the PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16), a transcriptional factor with a crucial role in brown adipocyte differentiation. EPO significantly increased phosphorylated signal transducer and activator of transcription 3 (STAT3), which is downstream of erythropoietin receptor (EpoR) and known to stabilize PRDM16. EPO’s suppression of myocyte enhancer factor 2c (Mef2c) and microRNA-133a (miR-133a) via β3-adrenergic receptor caused PRDM16 upregulation. EPO-mediated enhancement of EpoR/STAT3 and β-adrenergic receptor/Mef2c/miR-133 pathways dramatically increases total uncoupling protein 1 (UCP1), an essential enzyme for BAT thermogenesis. Furthermore, EPO activated BAT’s endocrine functions. EPO facilitated fibroblast growth factor 21 (FGF21) production and excretion in iBAT, associated with reduction of liver gluconeogenesis-related genes. Thus, EPO

  2. MDMA induces cardiac contractile dysfunction through autophagy upregulation and lysosome destabilization in rats.

    PubMed

    Shintani-ishida, Kaori; Saka, Kanju; Yamaguchi, Koji; Hayashida, Makiko; Nagai, Hisashi; Takemura, Genzou; Yoshida, Ken-ichi

    2014-05-01

    The underlying mechanisms of cardiotoxicity of 3,4-methylenedioxymethylamphetamine (MDMA, "ecstasy") abuse are unclear. Autophagy exerts either adaptive or maladaptive effects on cardiac function in various pathological settings, but nothing is known on the role of autophagy in the MDMA cardiotoxicity. Here, we investigated the mechanism through which autophagy may be involved in MDMA-induced cardiac contractile dysfunction. Rats were injected intraperitoneally with MDMA (20mg/kg) or saline. Left ventricular (LV) echocardiography and LV pressure measurement demonstrated reduction of LV systolic contractility 24h after MDMA administration. Western blot analysis showed a time-dependent increase in the levels of microtubule-associated protein light chain 3-II (LC3-II) and cathepsin-D after MDMA administration. Electron microscopy showed the presence of autophagic vacuoles in cardiomyocytes. MDMA upregulated phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) at Thr172, mammalian target of rapamycin (mTOR) at Thr2446, Raptor at Ser792, and Unc51-like kinase (ULK1) at Ser555, suggesting activation of autophagy through the AMPK-mTOR pathway. The effects of autophagic inhibitors 3-methyladenine (3-MA) and chloroquine (CQ) on LC3-II levels indicated that MDMA enhanced autophagosome formation, but attenuated autophagosome clearance. MDMA also induced release of cathepsins into cytosol, and western blotting and electron microscopy showed cardiac troponin I (cTnI) degradation and myofibril damage, respectively. 3-MA, CQ, and a lysosomal inhibitor, E64c, inhibited cTnI proteolysis and improved contractile dysfunction after MDMA administration. In conclusion, MDMA causes lysosome destabilization following activation of the autophagy-lysosomal pathway, through which released lysosomal proteases damage myofibrils and induce LV systolic dysfunction in rat heart.

  3. Ginger extract prevents high-fat diet-induced obesity in mice via activation of the peroxisome proliferator-activated receptor δ pathway.

    PubMed

    Misawa, Koichi; Hashizume, Kojiro; Yamamoto, Masaki; Minegishi, Yoshihiko; Hase, Tadashi; Shimotoyodome, Akira

    2015-10-01

    The initiation of obesity entails an imbalance wherein energy intake exceeds expenditure. Obesity is increasing in prevalence and is now a worldwide health problem. Food-derived peroxisome proliferator-activated receptor δ (PPARδ) stimulators represent potential treatment options for obesity. Ginger (Zingiber officinale Roscoe) was previously shown to regulate the PPARγ signaling pathway in adipocytes. In this study, we investigated the antiobesity effects of ginger in vivo and the mechanism of action in vitro. Energy expenditure was increased, and diet-induced obesity was attenuated in C57BL/6J mice treated with dietary ginger extract (GE). GE also increased the number of Type I muscle fibers, improved running endurance capacity and upregulated PPARδ-targeted gene expression in skeletal muscle and the liver. 6-Shogaol and 6-gingerol acted as specific PPARδ ligands and stimulated PPARδ-dependent gene expression in cultured human skeletal muscle myotubes. An analysis of cellular respiration revealed that pretreating cultured skeletal muscle myotubes with GE increased palmitate-induced oxygen consumption rate, which suggested an increase in cellular fatty acid catabolism. These results demonstrated that sustained activation of the PPARδ pathway with GE attenuated diet-induced obesity and improved exercise endurance capacity by increasing skeletal muscle fat catabolism. 6-Shogaol and 6-gingerol may be responsible for the regulatory effects of dietary ginger on PPARδ signaling.

  4. Stress induced obesity: lessons from rodent models of stress

    PubMed Central

    Patterson, Zachary R.; Abizaid, Alfonso

    2013-01-01

    Stress was once defined as the non-specific result of the body to any demand or challenge to homeostasis. A more current view of stress is the behavioral and physiological responses generated in the face of, or in anticipation of, a perceived threat. The stress response involves activation of the sympathetic nervous system and recruitment of the hypothalamic-pituitary-adrenal (HPA) axis. When an organism encounters a stressor (social, physical, etc.), these endogenous stress systems are stimulated in order to generate a fight-or-flight response, and manage the stressful situation. As such, an organism is forced to liberate energy resources in attempt to meet the energetic demands posed by the stressor. A change in the energy homeostatic balance is thus required to exploit an appropriate resource and deliver useable energy to the target muscles and tissues involved in the stress response. Acutely, this change in energy homeostasis and the liberation of energy is considered advantageous, as it is required for the survival of the organism. However, when an organism is subjected to a prolonged stressor, as is the case during chronic stress, a continuous irregularity in energy homeostasis is considered detrimental and may lead to the development of metabolic disturbances such as cardiovascular disease, type II diabetes mellitus and obesity. This concept has been studied extensively using animal models, and the neurobiological underpinnings of stress induced metabolic disorders are beginning to surface. However, different animal models of stress continue to produce divergent metabolic phenotypes wherein some animals become anorexic and lose body mass while others increase food intake and body mass and become vulnerable to the development of metabolic disturbances. It remains unclear exactly what factors associated with stress models can be used to predict the metabolic outcome of the organism. This review will explore a variety of rodent stress models and discuss the

  5. Obesity

    MedlinePlus

    ... In some cases, weight-loss surgery, also called bariatric surgery, is an option. Weight-loss surgery limits the ... et al. Treatment of obesity: The impact of bariatric surgery. In: Current Diagnosis & Treatment: Gastroenterology, Hepatology, & Endoscopy. 2nd ...

  6. Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

    PubMed

    Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

    2016-02-01

    Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

  7. Upregulation of complement inhibitors in association with vulnerable cells following contusion-induced spinal cord injury.

    PubMed

    Anderson, Aileen J; Najbauer, Joseph; Huang, Wencheng; Young, Wise; Robert, Stephanie

    2005-03-01

    We have previously described the activation of the classical, alternative, and terminal complement cascade pathways after acute contusion spinal cord injury using the New York University (NYU) weight-drop impactor. In the present study, we examined the induction of protein regulators of the complement cascade, factor H (FH), and clusterin, in the same experimental paradigm. The spinal cord of laminectomized adult rats was subjected to mild or severe injury using impactor weight-drop heights of 12.5 and 50 mm, respectively. The spinal cords of control and injured animals were evaluated at 1, 7, and 42 days after injury. Immunocytochemistry revealed a robust increase in the numbers and intensity of staining of FH, and clusterin-positive cells in the injured cord at all three time points, with the highest increases observed at 1 and 42 days after injury. FH and clusterin-positive cells were observed among neurons as well as oligodendrocytes. The increased expression was detected both rostrally and caudally from the injury site, in the latter case at distances up to 20 mm. The precise biological significance of injury-induced upregulation of these proteins remains to be determined. However, FH and clusterin are potent regulators of complement activity targeting upstream (FH) and downstream (clusterin) molecules of the pro-inflammatory cascade, which could be of vital importance in preventing a "runaway" inflammatory reaction in the injured spinal cord.

  8. Herbal Formula HT048 Attenuates Diet-Induced Obesity by Improving Hepatic Lipid Metabolism and Insulin Resistance in Obese Rats.

    PubMed

    Lee, Yoon Hee; Jin, Bora; Lee, Sung Hyun; Song, MiKyung; Bae, HyeonHui; Min, Byung Jae; Park, Juyeon; Lee, Donghun; Kim, Hocheol

    2016-10-25

    It is well established that obesity causes a variety of chronic diseases such as cardiovascular diseases and diabetes. Despite the diligent scientific efforts to find effective ways to lower the level of obesity, the size of obese population grows continuously around the world. Here we present the results that show feeding diet containing HT048, a mixture of the extracts of Crataegus pinnatifida leaves and Citrus unshiu peel, two of the well-known traditional herbal medicines in Eastern Asia, decreases obesity in rats. We fed rats with five different diets for 10 weeks: chow diet (STD), high-fat diet (HFD), high-fat diet with 0.04% orlistat, a drug to treat obesity (HFD + Orlistat), high-fat diet with 0.2% HT048 (w/w; HFD + 0.2% HT048), and high-fat diet with 0.6% HT048 (w/w; HFD + 0.6% HT048). It was found that both body and total white adipose tissue weight of HT048 groups significantly decreased compared to those of the HFD group. Moreover, HT048 decreased serum insulin levels in HFD-fed obese rats. At the molecular level, HT048 supplementation downregulated genes involved in lipogenesis, gluconeogenesis, and adipogenesis, while the expression level of β-oxidation genes was increased. Supplementation-drug interactions are not likely as HFD and HT048-containing diet did not significantly induce genes encoding CYPs. Collectively, this study suggests that HT048 taken as dietary supplement helps to decrease obesity and insulin resistance in HFD-fed obese rats.

  9. Phlorizin Supplementation Attenuates Obesity, Inflammation, and Hyperglycemia in Diet-Induced Obese Mice Fed a High-Fat Diet.

    PubMed

    Shin, Su-Kyung; Cho, Su-Jung; Jung, Un Ju; Ryu, Ri; Choi, Myung-Sook

    2016-02-16

    Obesity, along with its related complications, is a serious health problem worldwide. Many studies reported the anti-diabetic effect of phlorizin, while little is known about its anti-obesity effect. We investigated the beneficial effects of phlorizin on obesity and its complications, including diabetes and inflammation in obese animal. Male C57BL/6J mice were divided into three groups and fed their respective experimental diets for 16 weeks: a normal diet (ND, 5% fat, w/w), high-fat diet (HFD, 20% fat, w/w), or HFD supplemented with phlorizin (PH, 0.02%, w/w). The findings revealed that the PH group had significantly decreased visceral and total white adipose tissue (WAT) weights, and adipocyte size compared to the HFD. Plasma and hepatic lipids profiles also improved in the PH group. The decreased levels of hepatic lipids in PH were associated with decreased activities of enzymes involved in hepatic lipogenesis, cholesterol synthesis and esterification. The PH also suppressed plasma pro-inflammatory adipokines levels such as leptin, adipsin, tumor necrosis factor-α, monocyte chemoattractant protein-1, interferon-γ, and interleukin-6, and prevented HFD-induced collagen accumulation in the liver and WAT. Furthermore, the PH supplementation also decreased plasma glucose, insulin, glucagon, and homeostasis model assessment of insulin resistance levels. In conclusion, phlorizin is beneficial for preventing diet-induced obesity, hepatic steatosis, inflammation, and fibrosis, as well as insulin resistance.

  10. Lactobacillus plantarum HAC01 regulates gut microbiota and adipose tissue accumulation in a diet-induced obesity murine model.

    PubMed

    Park, Soyoung; Ji, Yosep; Jung, Hoe-Yune; Park, Hyunjoon; Kang, Jihee; Choi, Sang-Haeng; Shin, Heuynkil; Hyun, Chang-Kee; Kim, Kyong-Tai; Holzapfel, Wilhelm H

    2017-02-01

    The functional features of Lactobacillus plantarum HAC01 (HAC01), isolated from fermented Korean kimchi, were studied with regard to the fat mass, immunometabolic biomarkers and dysbiosis in a diet-induced obesity (DIO) murine model. L. rhamnosus GG (LGG) served as reference strain and a PBS-treated group as control. The administration of L. plantarum HAC01 resulted in reduction of the mesenteric adipose depot, the conjunctive tissue closely associated with the gastrointestinal tract, where lipid oxidative gene expression was upregulated compared to the control group. Metagenome analysis of intestinal microbiota showed that both strains HAC01 and LGG influenced specific bacterial families such as the Lachnospiraceae and Ruminococcaceae rather than the phyla Firmicutes and Bacteroidetes as a whole. The relative abundance of the Lachnospiraceae (phylum Firmicutes) was significantly higher in both LAB-treated groups than in the control. Comparing the impact of the two Lactobacillus strains on microbial composition in the gut also suggests strain-specific effects. The study emphasises the need for deeper studies into functional specificity of a probiotic organism at the strain level. Alleviation of obesity-associated dysbiosis by modulation of the gut microbiota appears to be associated with "indicator" bacterial taxa such as the family Lachnospiraceae. This may provide further insight into mechanisms basic to the mode of probiotic action against obesity and associated dysbiosis.

  11. Myeloid zinc finger 1 mediates sulindac sulfide-induced upregulation of death receptor 5 of human colon cancer cells

    PubMed Central

    Horinaka, Mano; Yoshida, Tatsushi; Tomosugi, Mitsuhiro; Yasuda, Shusuke; Sowa, Yoshihiro; Sakai, Toshiyuki

    2014-01-01

    A combined therapy of sulindac sulfide and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising strategy for the treatment of cancer. Sulindac sulfide had been shown to induce the expression of death receptor 5 (DR5), a receptor for TRAIL, and sensitize cancer cells to TRAIL-induced apoptosis; however, the molecular mechanism underlying the upregulation of DR5 has not yet been elucidated. We demonstrate here that myeloid zinc finger 1 (MZF1) mediates the induction of DR5 by sulindac sulfide. Sulindac sulfide induced the expression of DR5 at the protein and mRNA levels in colon cancer SW480 cells. Furthermore, sulindac sulfide increased DR5 promoter activity. We showed that sulindac sulfide stimulated DR5 promoter activity via the −301 to −253 region. This region contained a putative MZF1-binding site. Site-directed mutations in the site abrogated the enhancement in DR5 promoter activity by sulindac sulfide. MZF1 directly bound to the putative MZF1-binding site of the DR5 promoter and the binding was increased by sulindac sulfide. The expression of MZF1 was also increased by sulindac sulfide, and MZF1 siRNA attenuated the upregulation of DR5 by sulindac sulfide. These results indicate that sulindac sulfide induces the expression of DR5 by up-regulating MZF1. PMID:25102912

  12. Hepatocyte Toll-like receptor 4 regulates obesity-induced inflammation and insulin resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chronic low-grade inflammation is a hallmark of obesity and thought to contribute to the development of obesity-related insulin resistance. Toll-like receptor 4 (Tlr4) is a key mediator of pro-inflammatory responses. Mice lacking Tlr4s are protected from diet-induced insulin resistance and inflammat...

  13. SGK1 Activity is Modulated by Resistin in Vascular Smooth Muscle Cells and in the Aorta in Response to Diet-Induced Obesity

    PubMed Central

    Scott, Takara A.; Babayeva, Oguljahan; Banerjee, Saswati; Zhong, Wei; Francis, Sharon C.

    2016-01-01

    Objective Enhanced serum and glucocorticoid-inducible kinase 1 (SGK1) activity contributes to the pathogenesis of vascular disease. We evaluated SGK1 modulation in vascular smooth muscle cells by the adipokine, resistin and in aortic tissue in a murine model of diet-induced obesity (DIO). Methods Modulation of SGK1 by resistin was assessed in human aortic smooth muscle cells (HAoSMC) in vitro by quantitative RT-PCR and western blot analyses. To induce the lean or obese phenotype, mice were fed a 10 kcal% low-fat or 60 kcal% high-fat diet, respectively for eight weeks. Upon study completion, plasma resistin was assessed and aortic tissue was harvested to examine the effect of DIO on regulation of SGK1 in vivo. Results Resistin increased SGK1 mRNA, total protein abundance and its activation as determined by phosphorylation of its serine 422 residue (pSGK1) in HAoSMC. Resistin-mediated SGK1 phosphorylation was dependent upon phosphatidylinositol-3-kinase and Toll-like receptor 4. Furthermore, inhibition of SGK1 attenuated resistin-induced proliferation in HAoSMC. DIO led to upregulation of total SGK1 protein levels and pSGK1 in association with increased plasma resistin. Conclusions These data suggest that high levels of resistin observed during obesity may activate SGK1 in the vasculature and contribute to the development of obesity-related vascular disease. PMID:26833885

  14. NO-1886 suppresses diet-induced insulin resistance and cholesterol accumulation through STAT5-dependent upregulation of IGF1 and CYP7A1.

    PubMed

    Li, Qinkai; Yin, Weidong; Cai, Manbo; Liu, Yi; Hou, Hongjie; Shen, Qingyun; Zhang, Chi; Xiao, Junxia; Hu, Xiaobo; Wu, Qishisan; Funaki, Makoto; Nakaya, Yutaka

    2010-01-01

    Insulin resistance and dyslipidemia are both considered to be risk factors for metabolic syndrome. Low levels of IGF1 are associated with insulin resistance. Elevation of low-density lipoprotein cholesterol (LDL-C) concomitant with depression of high-density lipoprotein cholesterol (HDL-C) increase the risk of obesity and type 2 diabetes mellitus (T2DM). Liver secretes IGF1 and catabolizes cholesterol regulated by the rate-limiting enzyme of bile acid synthesis from cholesterol 7alpha-hydroxylase (CYP7A1). NO-1886, a chemically synthesized lipoprotein lipase activator, suppresses diet-induced insulin resistance with the improvement of HDL-C. The goal of the present study is to evaluate whether NO-1886 upregulates IGF1 and CYP7A1 to benefit glucose and cholesterol metabolism. By using human hepatoma cell lines (HepG2 cells) as an in vitro model, we found that NO-1886 promoted IGF1 secretion and CYP7A1 expression through the activation of signal transducer and activator of transcription 5 (STAT5). Pretreatment of cells with AG 490, the inhibitor of STAT pathway, completely abolished NO-1886-induced IGF1 secretion and CYP7A1 expression. Studies performed in Chinese Bama minipigs pointed out an augmentation of plasma IGF1 elicited by a single dose administration of NO-1886. Long-term supplementation with NO-1886 recovered hyperinsulinemia and low plasma levels of IGF1 suppressed LDL-C and facilitated reverse cholesterol transport by decreasing hepatic cholesterol accumulation through increasing CYP7A1 expression in high-fat/high-sucrose/high-cholesterol diet minipigs. These findings indicate that NO-1886 upregulates IGF1 secretion and CYP7A1 expression to improve insulin resistance and hepatic cholesterol accumulation, which may represent an alternative therapeutic avenue of NO-1886 for T2DM and metabolic syndrome.

  15. Calorie-induced ER stress suppresses uroguanylin satiety signaling in diet-induced obesity

    PubMed Central

    Kim, G W; Lin, J E; Snook, A E; Aing, A S; Merlino, D J; Li, P; Waldman, S A

    2016-01-01

    Background/Objectives: The uroguanylin-GUCY2C gut–brain axis has emerged as one component regulating feeding, energy homeostasis, body mass and metabolism. Here, we explore a role for this axis in mechanisms underlying diet-induced obesity (DIO). Subjects/Methods: Intestinal uroguanylin expression and secretion, and hypothalamic GUCY2C expression and anorexigenic signaling, were quantified in mice on high-calorie diets for 14 weeks. The role of endoplasmic reticulum (ER) stress in suppressing uroguanylin in DIO was explored using tunicamycin, an inducer of ER stress, and tauroursodeoxycholic acid (TUDCA), a chemical chaperone that inhibits ER stress. The impact of consumed calories on uroguanylin expression was explored by dietary manipulation. The role of uroguanylin in mechanisms underlying obesity was examined using Camk2a-Cre-ERT2-Rosa-STOPloxP/loxP-Guca2b mice in which tamoxifen induces transgenic hormone expression in brain. Results: DIO suppressed intestinal uroguanylin expression and eliminated its postprandial secretion into the circulation. DIO suppressed uroguanylin through ER stress, an effect mimicked by tunicamycin and blocked by TUDCA. Hormone suppression by DIO reflected consumed calories, rather than the pathophysiological milieu of obesity, as a diet high in calories from carbohydrates suppressed uroguanylin in lean mice, whereas calorie restriction restored uroguanylin in obese mice. However, hypothalamic GUCY2C, enriched in the arcuate nucleus, produced anorexigenic signals mediating satiety upon exogenous agonist administration, and DIO did not impair these responses. Uroguanylin replacement by transgenic expression in brain repaired the hormone insufficiency and reconstituted satiety responses opposing DIO and its associated comorbidities, including visceral adiposity, glucose intolerance and hepatic steatosis. Conclusions: These studies reveal a novel pathophysiological mechanism contributing to obesity in which calorie-induced suppression

  16. Thrombospondin-1 regulates adiposity and metabolic dysfunction in diet-induced obesity enhancing adipose inflammation and stimulating adipocyte proliferation

    PubMed Central

    Kong, Ping; Gonzalez-Quesada, Carlos; Li, Na; Cavalera, Michele; Lee, Dong-Wook

    2013-01-01

    As a typical matricellular protein, thrombospondin (TSP)-1, binds to the structural matrix and regulates cellular behavior by modulating growth factor and cytokine signaling. Obesity and diabetes are associated with marked upregulation of TSP-1 in adipose tissue. We hypothesized that endogenous TSP-1 may play an important role in the pathogenesis of diet-induced obesity and metabolic dysfunction. Accordingly, we examined the effects of TSP-1 gene disruption on weight gain, adiposity, and adipose tissue inflammation in mice receiving a high-fat diet (HFD: 60% fat, 20% carbohydrate) or a high-carbohydrate low-fat diet (HCLFD: 10% fat, 70% carbohydrate). HFD mice had significantly higher TSP-1 expression in perigonadal adipose tissue; TSP-1 was predominantly localized in the adipose interstitium. TSP-1 loss attenuated weight gain and fat accumulation in HFD and HCLFD groups. Compared with corresponding wild-type animals, TSP-1-null mice had decreased insulin levels but exhibited elevated free fatty acid and triglyceride levels, suggesting impaired fatty acid uptake. TSP-1 loss did not affect adipocyte size and had no effect on adipose vascular density. However, TSP-1-null mice exhibited attenuated tumor necrosis factor-α mRNA expression and reduced macrophage infiltration, suggesting a role for TSP-1 in mediating obesity-associated inflammation. In vitro, TSP-1 enhanced proliferation of 3T3-L1 preadipocytes but did not modulate inflammatory cytokine and chemokine synthesis. In conclusion, TSP-1 upregulation contributes to weight gain, adipose growth, and the pathogenesis of metabolic dysfunction. The effects of TSP-1 may involve stimulation of adipocyte proliferation, activation of inflammatory signaling, and facilitated fatty acid uptake by adipocytes. PMID:23757408

  17. Contact with enterocyte-like Caco-2 cells induces rapid upregulation of toxin production by Clostridium perfringens type C isolates

    PubMed Central

    Vidal, Jorge E.; Ohtani, Kaori; Shimizu, Tohru; McClane, Bruce A.

    2009-01-01

    Clostridium perfringens type C isolates cause necrotizing enteritis in humans and domestic animals. In vitro, type C isolates often produce beta toxin (CPB), beta2 toxin (CPB2), alpha toxin (CPA), perfringolysin O (PFO), and TpeL during (or after) late log-phase growth. In contrast, the current study found that many type C isolates respond to close contact with enterocyte-like Caco-2 cells by producing all toxins, except TpeL, much more rapidly than occurs during in vitro growth. This in vivo effect involves rapid transcriptional upregulation of the cpb, cpb2, pfoA and plc toxin genes. Rapid Caco-2 cell-induced upregulation of CPB and PFO production involves the VirS/VirR two-component system, since upregulated in vivo transcription of the pfoA and cpb genes was blocked by inactivating the virR gene and was reversible by complementation to restore VirR expression. However, the luxS quorum sensing system is not required for the rapid upregulation of type C toxin production induced by contact with Caco-2 cells. These results provide the first indication of host cell:pathogen cross-talk affecting toxin production kinetics by any pathogenic Clostridium spp., identify in vivo vs. in vitro differences in C. perfringens toxin expression, and implicate VirS/VirR as a possible contributor to some C. perfringens enteric diseases. PMID:19438515

  18. Reversal of diet-induced obesity and insulin resistance by inducible genetic ablation of GRK2

    PubMed Central

    Vila-Bedmar, Rocio; Cruces-Sande, Marta; Lucas, Elisa; Willemen, Hanneke L.D.M.; Heijnen, Cobi J.; Kavelaars, Annemieke; Mayor, Federico; Murga, Cristina

    2015-01-01

    Insulin resistance is a common feature of obesity and predisposes individuals to various prevalent pathological conditions. G protein-coupled receptor kinase 2 (GRK2) integrates several signal transduction pathways and is emerging as a physiologically relevant inhibitor of insulin signaling. GRK2 abundanceis increased in humans with metabolic syndrome and in different murine models of insulin resistance. To support GRK2 as a potential drug target in type 2 diabetes and obesity, we investigated whether lowering GRK2 abundance reversed an ongoing systemic insulin-resistant phenotype, using a mouse model of tamoxifen-induced GRK2 ablation after high fat diet-dependent obesity and insulin resistance. Tamoxifen-triggered GRK2 deletion impeded further body weight gain, normalized fa sting glycemia, improved glucose tolerance and was associated with preserved insulin sensitivity in skeletal muscle and liver, thereby maintaining whole body glucose homeostasis. Moreover, when continued to be fed a high fat diet, these animals displayed reduced fat mass and smaller adipocytes, were resistant to the development of liver steatosis, and showed reduced expression of pro-inflammatory markers in the liver. Our results indicate that GRK2 acts as a hub to control metabolic functions in different tissues, which is key to controlling insulin resistance development in vivo. These data suggest that inhibiting GRK2 could reverse an established insulin-resistant and obese phenotype, thereby putting forward this enzyme as a potential therapeutic target linking glucose homeostasis and regulation of adiposity. PMID:26198359

  19. CD11c expression in adipose tissue and blood and its role in diet-induced obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To examine CD11c, a beta(2)-integrin, on adipose tissue (AT) leukocytes, and blood monocytes and its role in diet-induced obesity. High-fat diet-induced obese C57BL/6 mice, CD11c-deficient mice, and obese humans were studied. CD11c, leukocytes, and chemokines/cytokines were examined in AT and/or blo...

  20. An assessment of molecular pathways of obesity susceptible to nutrient, toxicant and genetically induced epigenetic perturbation.

    PubMed

    Xue, Jing; Ideraabdullah, Folami Y

    2016-04-01

    In recent years, the etiology of human disease has greatly improved with the inclusion of epigenetic mechanisms, in particular as a common link between environment and disease. However, for most diseases we lack a detailed interpretation of the epigenetic regulatory pathways perturbed by environment and causal mechanisms. Here, we focus on recent findings elucidating nutrient-related epigenetic changes linked to obesity. We highlight studies demonstrating that obesity is a complex disease linked to disruption of epigenetically regulated metabolic pathways in the brain, adipose tissue and liver. These pathways regulate (1) homeostatic and hedonic eating behaviors, (2) adipocyte differentiation and fat accumulation, and (3) energy expenditure. By compiling these data, we illustrate that obesity-related phenotypes are repeatedly linked to disruption of critical epigenetic mechanisms that regulate key metabolic genes. These data are supported by genetic mutation of key epigenetic regulators, and many of the diet-induced epigenetic mechanisms of obesity are also perturbed by exposure to environmental toxicants. Identifying similarly perturbed epigenetic mechanisms in multiple experimental models of obesity strengthens the translational applications of these findings. We also discuss many of the ongoing challenges to understanding the role of environmentally induced epigenetic pathways in obesity and suggest future studies to elucidate these roles. This assessment illustrates our current understanding of molecular pathways of obesity that are susceptible to environmental perturbation via epigenetic mechanisms. Thus, it lays the groundwork for dissecting the complex interactions between diet, genes and toxicants that contribute to obesity and obesity-related phenotypes.

  1. An assessment of molecular pathways of obesity susceptible to nutrient, toxicant and genetically induced epigenetic perturbation

    PubMed Central

    Xue, Jing; Ideraabdullah, Folami Y.

    2015-01-01

    In recent years, the etiology of human disease has greatly improved with the inclusion of epigenetic mechanisms, in particular as a common link between environment and disease. However, for most diseases we lack a detailed interpretation of the epigenetic regulatory pathways perturbed by environment and causal mechanisms. Here, we focus on recent findings elucidating nutrient-related epigenetic changes linked to obesity. We highlight studies demonstrating that obesity is a complex disease linked to disruption of epigenetically regulated metabolic pathways in the brain, adipose tissue and liver. These pathways regulate (1) homeostatic and hedonic eating behaviors (2) adipocyte differentiation and fat accumulation, and (3) energy expenditure. By compiling these data we illustrate that obesity-related phenotypes are repeatedly linked to disruption of critical epigenetic mechanisms that regulate of key metabolic genes. These data are supported by genetic mutation of key epigenetic regulators and many of the diet induced epigenetic mechanisms of obesity are also perturbed by exposure to environmental toxicants. Identifying similarly perturbed epigenetic mechanisms in multiple experimental models of obesity strengthens the translational applications of these findings. We also discuss many of the ongoing challenges to understanding the role of environmentally-induced epigenetic pathways in obesity and suggest future studies to elucidate these roles. This assessment illustrates our current understanding of molecular pathways of obesity that are susceptible to environmental perturbation via epigenetic mechanisms. Thus, it lays the groundwork for dissecting the complex interactions between diet, genes, and toxicants that contribute to obesity and obesity-related phenotypes. PMID:27012616

  2. Fermented green tea extract alleviates obesity and related complications and alters gut microbiota composition in diet-induced obese mice.

    PubMed

    Seo, Dae-Bang; Jeong, Hyun Woo; Cho, Donghyun; Lee, Bum Jin; Lee, Ji Hae; Choi, Jae Young; Bae, Il-Hong; Lee, Sung-Joon

    2015-05-01

    Obesity is caused by an imbalance between caloric intake and energy expenditure and accumulation of excess lipids in adipose tissues. Recent studies have demonstrated that green tea and its processed products (e.g., oolong and black tea) are introduced to exert beneficial effects on lipid metabolism. Here, we propose that fermented green tea (FGT) extract, as a novel processed green tea, exhibits antiobesity effects. FGT reduced body weight gain and fat mass without modifying food intake. mRNA expression levels of lipogenic and inflammatory genes were downregulated in white adipose tissue of FGT-administered mice. FGT treatment alleviated glucose intolerance and fatty liver symptoms, common complications of obesity. Notably, FGT restored the changes in gut microbiota composition (e.g., the Firmicutes/Bacteroidetes and Bacteroides/Prevotella ratios), which is reported to be closely related with the development of obesity and insulin resistance, induced by high-fat diets. Collectively, FGT improves obesity and its associated symptoms and modulates composition of gut microbiota; thus, it could be used as a novel dietary component to control obesity and related symptoms.

  3. Apelin-13-induced proliferation and migration induced of rat vascular smooth muscle cells is mediated by the upregulation of Egr-1

    SciTech Connect

    Liu, Qi-Feng; Yu, Hong-Wei; You, Lu; Liu, Ming-Xin; Li, Ke-Yan; Tao, Gui-Zhou

    2013-09-20

    Highlights: •The mechanism underlying the effects of Apelin-13 on VSMC was investigated. •Apelin-13 induced VSMC migration, proliferation and Egr-1 and OPN upregulation. •These effects were inhibited by the Egr-1 specific deoxyribozyme, ED5. •The effects of Apelin-13 on VSMC are mediated via Egr-1 upregulation. •These data will help in attempts to prevent and treat vascular remodeling diseases. -- Abstract: Apelin-13 plays an important role in the migration and proliferation of vascular smooth muscle cells (VSMCs); however, the underlying mechanisms are still unclear. Egr-1 is a nuclear transcription factor, which is considered to be the critical initiating factor of the processes of VSMC proliferation and migration. Egr-1 is known to regulate the expression of osteopontin (OPN), which is a marker of the phenotypic modulation that is a necessary condition of VSMC proliferation and migration. We hypothesized that the role of Apelin-13 is mediated via upregulation of Egr-1. To test this hypothesis, we analyzed the effects of Apelin-13 treatment on Egr-1 mRNA and protein expression in A10 rat aortic VSMCs by RT-PCR and Western blotting, respectively. Results showed that, Apelin-13 upregulated the expression of Egr-1. Furthermore, treatment with the extracellular-regulated protein kinase (ERK) inhibitor, PD98059, inhibited the upregulation of Egr-1 by Apelin-13. In addition, this upregulation was inhibited by treatment of VSMCs with the Egr-1 specific deoxyribozyme ED5 (DNAenzyme/10-23 DRz). Furthermore, ED5 treatment was found to significantly inhibit Apelin-13-induced migration and proliferation of VSMCs using transwell and MTT assays, respectively. The evaluation of OPN mRNA and protein expression levels by RT-PCR and Western blot analyses revealed that ED5 treatment also inhibited Apelin-13-induced OPN upregulation. The results of this study indicated that Apelin-13 upregulates Egr-1 via ERK. Furthermore, Apelin-13 induced the proliferation and migration

  4. Up-Regulation of Claudin-6 in the Distal Lung Impacts Secondhand Smoke-Induced Inflammation

    PubMed Central

    Lewis, Joshua B.; Milner, Dallin C.; Lewis, Adam L.; Dunaway, Todd M.; Egbert, Kaleb M.; Albright, Scott C.; Merrell, Brigham J.; Monson, Troy D.; Broberg, Dallin S.; Gassman, Jason R.; Thomas, Daniel B.; Arroyo, Juan A.; Reynolds, Paul R.

    2016-01-01

    It has long been understood that increased epithelial permeability contributes to inflammation observed in many respiratory diseases. Recently, evidence has revealed that environmental exposure to noxious material such as cigarette smoke reduces tight junction barrier integrity, thus enhancing inflammatory conditions. Claudin-6 (Cldn6) is a tetraspanin transmembrane protein found within the tight junctional complex and is implicated in maintaining lung epithelial barriers. To test the hypothesis that increased Cldn6 ameliorates inflammation at the respiratory barrier, we utilized the Tet-On inducible transgenic system to conditionally over-express Clnd6 in the distal lung. Cldn6 transgenic (TG) and control mice were continuously provided doxycycline from postnatal day (PN) 30 until euthanasia date at PN90. A subset of Cldn6 TG and control mice were also subjected to daily secondhand tobacco smoke (SHS) via a nose only inhalation system from PN30-90 and compared to room air (RA) controls. Animals were euthanized on PN90 and lungs were harvested for histological and molecular characterization. Bronchoalveolar lavage fluid (BALF) was procured for the assessment of inflammatory cells and molecules. Quantitative RT-PCR and immunoblotting revealed increased Cldn6 expression in TG vs. control animals and SHS decreased Cldn6 expression regardless of genetic up-regulation. Histological evaluations revealed no adverse pulmonary remodeling via Hematoxylin and Eosin (H&E) staining or any qualitative alterations in the abundance of type II pneumocytes or proximal non-ciliated epithelial cells via staining for cell specific propeptide of Surfactant Protein-C (proSP-C) or Club Cell Secretory Protein (CCSP), respectively. Immunoblotting and qRT-PCR confirmed the differential expression of Cldn6 and the pro-inflammatory cytokines TNF-α and IL-1β. As a general theme, inflammation induced by SHS exposure was influenced by the availability of Cldn6. These data reveal captivating

  5. Maternal obesity induces fibrosis in fetal myocardium of sheep

    PubMed Central

    Huang, Yan; Yan, Xu; Zhao, Jun X.; Zhu, Mei J.; McCormick, Richard J.; Ford, Stephen P.; Nathanielsz, Peter W.; Ren, Jun

    2010-01-01

    Maternal obesity (MO) has harmful effects on both fetal development and subsequent offspring health. The impact of MO on fetal myocardium development has received little attention. Fibrogenesis is regulated by the transforming growth factor-β (TGF-β)/p38 signaling pathway. Using the well-established model of MO in pregnant sheep, we evaluated the effect of MO on TGF-β/p38 and collagen accumulation in fetal myocardium. Nonpregnant ewes were assigned to a control diet [Con, fed 100% of National Research Council (NRC) nutrient recommendations] or obesogenic diet (OB, fed 150% of NRC recommendations) from 60 days before conception. Fetal ventricular muscle was sampled at 75 and 135 days of gestation (dG). At 75 dG, the expression of precursor TGF-β was 39.9 ± 9.9% higher (P < 0.05) in OB than Con fetal myocardium, consistent with the higher content of phosphorylated Smad3 in OB myocardium. The phosphorylation of p38 tended to be higher in OB myocardium (P = 0.08). In addition, enhanced Smad complexes were bound to Smad-binding elements in 75 dG OB fetal myocardium measured by DNA mobility shift assay (130.2 ± 26.0% higher, P < 0.05). Similar elevation of TGF-β signaling was observed in OB fetal myocardium at 135 dG. Total collagen concentration in OB was greater than Con fetal myocardium (2.42 ± 0.16 vs. 1.87 ± 0.04%, P < 0.05). Matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-3 were higher in the Con group compared with OB sheep (43.86 ± 16.01 and 37.23 ± 7.97% respectively, P < 0.05). In summary, MO results in greater fetal heart connective tissue accumulation associated with an upregulated TGF-β/p38 signaling pathway at late gestation; such changes would be expected to negatively impact offspring heart function. PMID:20876759

  6. Intranasal leptin reduces appetite and induces weight loss in rats with diet-induced obesity (DIO).

    PubMed

    Schulz, Carla; Paulus, Kerstin; Jöhren, Olaf; Lehnert, Hendrik

    2012-01-01

    Resistance to brain-mediated effects of leptin is a characteristic feature of obesity, resulting from alterations in leptin receptor signaling in hypothalamic neurons and/or transport across the blood-brain-barrier. We have shown previously, that the latter can be circumvented by intranasal (i.n.) application of leptin in lean rats. This prompted us to test i.n. leptin in animals with diet-induced obesity (DIO) as a basis for future human administration. DIO was induced in male Wistar rats by feeding a cafeteria diet for 25 or 32 wk, respectively. Consecutively, these DIO animals (seven to eight per treatment) and standard diet rats (lean) (14-15 per treatment, matched for age and diet duration) were treated with 0.1, 0.2 mg/kg leptin, or control solution i.n. daily for 4 wk before onset of dark period. Energy intake and body weight were measured daily; blood glucose, serum insulin, and leptin were measured before and after treatment. Expression of hypothalamic neuropeptides was assessed by quantitative real-time PCR. We demonstrate, for the first time, that i.n. leptin reduces appetite and induces weight loss in DIO to the same extent as in lean rats. Our findings are supported accordingly by an altered expression pattern of anorexigenic and orexigenic neuropeptides in the hypothalamus, e.g. proopiomelanocortin, cocaine and amphetamine-related transcript, neuropeptide Y, agouti-related protein. It now appears clear that i.n. leptin is effectively acting in obese animals in the same fashion as in their lean counterparts. These findings now clearly warrant studies in humans and may open new perspectives in the treatment of obesity.

  7. Obesity

    MedlinePlus

    ... little free time may have less time to exercise. The term eating disorder means a group of medical conditions that have an unhealthy focus on eating, dieting, losing or gaining weight, and body image. A person may be obese, follow an unhealthy ...

  8. Flurbiprofen ameliorated obesity by attenuating leptin resistance induced by endoplasmic reticulum stress

    PubMed Central

    Hosoi, Toru; Yamaguchi, Rie; Noji, Kikuko; Matsuo, Suguru; Baba, Sachiko; Toyoda, Keisuke; Suezawa, Takahiro; Kayano, Takaaki; Tanaka, Shinpei; Ozawa, Koichiro

    2014-01-01

    Endoplasmic reticulum (ER) stress, caused by the accumulation of unfolded proteins, is involved in the development of obesity. We demonstrated that flurbiprofen, a nonsteroidal anti-inflammatory drug (NSAID), exhibited chaperone activity, which reduced protein aggregation and alleviated ER stress-induced leptin resistance, characterized by insensitivity to the actions of the anti-obesity hormone leptin. This result was further supported by flurbiprofen attenuating high-fat diet-induced obesity in mice. The other NSAIDs tested did not exhibit such effects, which suggested that this anti-obesity action is mediated independent of NSAIDs. Using ferriteglycidyl methacrylate beads, we identified aldehyde dehydrogenase as the target of flurbiprofen, but not of the other NSAIDs. These results suggest that flurbiprofen may have unique pharmacological properties that reduce the accumulation of unfolded proteins and may represent a new class of drug for the fundamental treatment of obesity. Subject Categories Metabolism; Pharmacology & Drug Discovery PMID:24421337

  9. Deep brain stimulation of the nucleus accumbens shell induces anti-obesity effects in obese rats with alteration of dopamine neurotransmission.

    PubMed

    Zhang, Chao; Wei, Nai-Li; Wang, Yao; Wang, Xiu; Zhang, Jian-Guo; Zhang, Kai

    2015-03-04

    The aim of this study was to assess the anti-obesity effects of nucleus accumbens shell (NAc-sh) deep brain stimulation (DBS) in diet-induced obese (DIO) and chow-fed (chow) rats. The influence of DBS on dopamine (DA) signaling in the NAc-sh was also evaluated. DIO and chow rats were subjected to DBS for 14 consecutive days. Food intake and weight gain were measured daily. The gene expression of the dopamine D1 and D2 receptors was evaluated by qPCR. In addition, the extracellular levels of DA and its metabolite, dihydroxyphenylacetic acid (DOPAC), were determined by microdialysis. We observed that chronic DBS induced significant reductions in total energy intake (596.0±65.0kcal vs. 1161.6±22.2kcal, p<0.001) and weight gain (1.45±0.57% vs. 9.64±0.38%, p<0.001) in DIO rats compared to sham-DIO rats. Up-regulated D2 receptor gene expression (2.43±0.12 vs. 0.64±0.04, p<0.001) and increased DA levels (2.73±0.15pmol/mL vs. 0.62±0.05pmol/mL, p<0.001) were observed in DIO rats compared to sham-DIO rats. DBS had no influence on food intake, weight gain, or DA neurotransmission in chow rats. Our results support an association of the anorexigenic effects of NAc-sh DBS with mesolimbic DA signaling and indicate that the positive alteration of DA function in DIO rats may be responsible for the different effects of DBS in DIO and chow rats.

  10. Pterostilbene-induced changes in gut microbiota compositon in relation to obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scope: Nutritional interventions based on the use of bioactive natural compounds might offer new possibilities for reshaping obesity-associated bacterial dysregulation or dysbiosis and improving health. We evaluated whether pterostilbene supplementation could induce changes in gut microbiota (GM) an...

  11. Diet-induced obesity in male mice is associated with reduced fertility and potentiation of acrylamide-induced reproductive toxicity.

    PubMed

    Ghanayem, Burhan I; Bai, Re; Kissling, Grace E; Travlos, Greg; Hoffler, Undi

    2010-01-01

    The prevalence of human obesity and related chronic disorders such as diabetes, cardiovascular diseases, and cancer is rapidly increasing. Human studies have shown a direct relationship between obesity and infertility. The objective of the current work was to examine the effect of diet-induced obesity on male fertility and the effect of obesity on susceptibility to chemical-induced reproductive toxicity. From 5 to 30 wk of age, genetically intact male C57Bl/6J mice were fed a normal diet or one in which 60% of the kilocalories were from lard. Obese mice exhibited significant differences in the mRNA of several genes within the testes in comparison to lean males. Pparg was increased 2.2-fold, whereas Crem, Sh2b1, Dhh, Igf1, and Lepr were decreased 6.7, 1.4, 3.2, 1.6, and 7.2-fold, respectively. The fertility of male mice was compared through mating with control females. Acrylamide (AA)-induced reproductive toxicity was assessed in obese or lean males treated with water or 25 mg AA kg(-1) day(-1) via gavage for 5 days and then mated to control females. Percent body fat and weight were significantly increased in mice fed a high-fat vs. a normal diet. Obesity resulted in significant reduction in plugs and pregnancies of control females partnered with obese vs. lean males. Serum leptin and insulin levels were each approximately 5-fold higher in obese vs. age-matched lean mice. Sperm from obese males exhibited decreased motility and reduced hyperactivated progression vs. lean mice. Treatment with AA exacerbated male infertility of obese and lean mice; however, this effect was more pronounced in obese mice. Further, females partnered with AA-treated obese mice exhibited a further decrease in the percentage of live fetuses, whereas the percentage of resorptions increased. This work demonstrated that diet-induced obesity in mice caused a significant reduction in male fertility and exacerbated AA-induced reproductive toxicity and germ cell mutagenicity.

  12. Feeding-induced oleoylethanolamide mobilization is disrupted in the gut of diet-induced obese rodents

    PubMed Central

    Igarashi, Miki; DiPatrizio, Nicholas V.; Narayanaswami, Vidya; Piomelli, Daniele

    2015-01-01

    The gastrointestinal tract plays a critical role in the regulation of energy homeostasis by initiating neural and hormonal responses to the ingestion of nutrients. In addition to peptide hormones, such as cholecystokinin (CKK) and peptide YY (PYY), the lipid-derived mediator oleoylethanolamide (OEA) has been implicated in the control of satiety. Previous studies in humans and rodent models have shown that obesity is associated with changes in CCK, PYY and other gut-derived peptide hormones, which may contribute to decreased satiety and increased energy intake. In the present study, we show that small-intestinal OEA production is disrupted in the gut of diet-induced obese (DIO) rats and mice. In lean rodents, feeding or duodenal infusion of Intralipid® or pure oleic acid stimulate jejunal OEA mobilization. This response is strikingly absent in DIO rats and mice. Confirming previous reports, we found that feeding rats or mice a high-fat diet for 7 days is sufficient to suppress jejunal OEA mobilization. Surprisingly, a similar effect is elicited by feeding rats and mice a high-sucrose low-fat diet for 7 days. Collectively, our findings suggest that high fat-induced obesity is accompanied by alterations in the post-digestive machinery responsible for OEA biosynthesis, which may contribute to reduced satiety and hyperphagia. PMID:26024927

  13. Modeling Diet-Induced Obesity with Obesity-Prone Rats: Implications for Studies in Females

    PubMed Central

    Giles, Erin D.; Jackman, Matthew R.; MacLean, Paul S.

    2016-01-01

    Obesity is a worldwide epidemic, and the comorbidities associated with obesity are numerous. Over the last two decades, we and others have employed an outbred rat model to study the development and persistence of obesity, as well as the metabolic complications that accompany excess weight. In this review, we summarize the strengths and limitations of this model and how it has been applied to further our understanding of human physiology in the context of weight loss and weight regain. We also discuss how the approach has been adapted over time for studies in females and female-specific physiological conditions, such as menopause and breast cancer. As excess weight and the accompanying metabolic complications have become common place in our society, we expect that this model will continue to provide a valuable translational tool to establish physiologically relevant connections to the basic science studies of obesity and body weight regulation. PMID:27933296

  14. Obesity-induced hypertension: interaction of neurohumoral and renal mechanisms.

    PubMed

    Hall, John E; do Carmo, Jussara M; da Silva, Alexandre A; Wang, Zhen; Hall, Michael E

    2015-03-13

    Excess weight gain, especially when associated with increased visceral adiposity, is a major cause of hypertension, accounting for 65% to 75% of the risk for human primary (essential) hypertension. Increased renal tubular sodium reabsorption impairs pressure natriuresis and plays an important role in initiating obesity hypertension. The mediators of abnormal kidney function and increased blood pressure during development of obesity hypertension include (1) physical compression of the kidneys by fat in and around the kidneys, (2) activation of the renin-angiotensin-aldosterone system, and (3) increased sympathetic nervous system activity. Activation of the renin-angiotensin-aldosterone system is likely due, in part, to renal compression, as well as sympathetic nervous system activation. However, obesity also causes mineralocorticoid receptor activation independent of aldosterone or angiotensin II. The mechanisms for sympathetic nervous system activation in obesity have not been fully elucidated but may require leptin and activation of the brain melanocortin system. With prolonged obesity and development of target organ injury, especially renal injury, obesity-associated hypertension becomes more difficult to control, often requiring multiple antihypertensive drugs and treatment of other risk factors, including dyslipidemia, insulin resistance and diabetes mellitus, and inflammation. Unless effective antiobesity drugs are developed, the effect of obesity on hypertension and related cardiovascular, renal and metabolic disorders is likely to become even more important in the future as the prevalence of obesity continues to increase.

  15. Inducible nitric oxide synthase expression in chronic viral hepatitis. Evidence for a virus-induced gene upregulation.

    PubMed Central

    Majano, P L; García-Monzón, C; López-Cabrera, M; Lara-Pezzi, E; Fernández-Ruiz, E; García-Iglesias, C; Borque, M J; Moreno-Otero, R

    1998-01-01

    Increased nitric oxide (NO) production may contribute to the pathological changes featuring in some inflammatory diseases, but the role of NO in chronic viral hepatitis is still unknown. We compared the inducible NO synthase (NOS2) expression in the liver of patients with chronic viral hepatitis with that of both nonviral liver disease and histologically normal liver. NOS2 expression was assessed by immunohistochemical and in situ hybridization studies of liver biopsy sections. An intense hepatocellular NOS2 reactivity was detected in chronic viral hepatitis, whereas it was weakly or not observed in nonviral liver disease or normal liver, respectively. In addition, we determined whether the hepatitis B virus (HBV) might regulate the synthesis of this enzyme. NOS2 mRNA and protein levels as well as enzyme activity were assessed in cytokine-stimulated HBV-transfected and untransfected hepatoma cells. Transfection with either HBV genome or HBV X gene resulted in induction of NOS2 mRNA expression, and the maximal induction of this transcript and NO production was observed in cytokine-stimulated HBV-transfected cells. These results indicate that hepatotropic viral infections are able to upregulate the NOS2 gene expression in human hepatocytes, suggesting that NO may mediate important pathogenic events in the course of chronic viral hepatitis. PMID:9525976

  16. Trimethyltin-induced apoptosis is associated with upregulation of inducible nitric oxide synthase and Bax in a hippocampal cell line

    SciTech Connect

    Zhang, L.; Li, L.; Prabhakaran, K.; Borowitz, J.L.; Isom, G.E. . E-mail: geisom@purdue.edu

    2006-10-01

    Trimethyltin (TMT) produces selective neuronal degeneration in the central nervous system (CNS), in which the hippocampus is the most sensitive area. Since previous studies have been conducted in either non-neural cells or mixed primary cultures, an immortalized hippocampal neuronal cell line (HT-22 cell) was used to assess the mechanism and mode of death produced by TMT. The compound produced a time- and concentration-dependent apoptotic death that was caspase-mediated. Excessive generation of reactive oxygen species (ROS) and subsequent reduction of mitochondrial membrane potential ({delta}{psi}{sub m}) were involved in the cytotoxicity{sub .} Scavenging of ROS by a free radical trapping agent or inhibition of the mitochondrial permeability transition (MPT) pore significantly reduced cell death. Additionally, TMT increased expression of inducible nitric oxide synthase (iNOS) by activation of the redox-sensitive transcription factor NF{kappa}B. Pharmacologic inhibition studies showed that the iNOS-mediated NO generation increased expression of Bax and then mitochondrial-mediated apoptosis. It was concluded that excessive ROS generation initiated the apoptotic cell death by upregulating iNOS followed by increased Bax expression which then led to loss of {delta}{psi}{sub m} and caspase-executed cell death. This study is the first to report in a neuronal cell model that TMT stimulates induction of iNOS, which then increases cellular levels of reactive nitrogen species (RNS) to initiate apoptotic death.

  17. Obesity-induced chronic inflammation in high fat diet challenged C57BL/6J mice is associated with acceleration of age-dependent renal amyloidosis.

    PubMed

    van der Heijden, Roel A; Bijzet, Johan; Meijers, Wouter C; Yakala, Gopala K; Kleemann, Robert; Nguyen, Tri Q; de Boer, Rudolf A; Schalkwijk, Casper G; Hazenberg, Bouke P C; Tietge, Uwe J F; Heeringa, Peter

    2015-11-13

    Obesity-induced inflammation presumably accelerates the development of chronic kidney diseases. However, little is known about the sequence of these inflammatory events and their contribution to renal pathology. We investigated the effects of obesity on the evolution of age-dependent renal complications in mice in conjunction with the development of renal and systemic low-grade inflammation (LGI). C57BL/6J mice susceptible to develop age-dependent sclerotic pathologies with amyloid features in the kidney, were fed low (10% lard) or high-fat diets (45% lard) for 24, 40 and 52 weeks. HFD-feeding induced overt adiposity, altered lipid and insulin homeostasis, increased systemic LGI and adipokine release. HFD-feeding also caused renal upregulation of pro-inflammatory genes, infiltrating macrophages, collagen I protein, increased urinary albumin and NGAL levels. HFD-feeding severely aggravated age-dependent structural changes in the kidney. Remarkably, enhanced amyloid deposition rather than sclerosis was observed. The degree of amyloidosis correlated significantly with body weight. Amyloid deposits stained positive for serum amyloid A (SAA) whose plasma levels were chronically elevated in HFD mice. Our data indicate obesity-induced chronic inflammation as a risk factor for the acceleration of age-dependent renal amyloidosis and functional impairment in mice, and suggest that obesity-enhanced chronic secretion of SAA may be the driving factor behind this process.

  18. Obesity-induced chronic inflammation in high fat diet challenged C57BL/6J mice is associated with acceleration of age-dependent renal amyloidosis

    PubMed Central

    van der Heijden, Roel A.; Bijzet, Johan; Meijers, Wouter C.; Yakala, Gopala K.; Kleemann, Robert; Nguyen, Tri Q.; de Boer, Rudolf A.; Schalkwijk, Casper G.; Hazenberg, Bouke P. C.; Tietge, Uwe J. F.; Heeringa, Peter

    2015-01-01

    Obesity-induced inflammation presumably accelerates the development of chronic kidney diseases. However, little is known about the sequence of these inflammatory events and their contribution to renal pathology. We investigated the effects of obesity on the evolution of age-dependent renal complications in mice in conjunction with the development of renal and systemic low-grade inflammation (LGI). C57BL/6J mice susceptible to develop age-dependent sclerotic pathologies with amyloid features in the kidney, were fed low (10% lard) or high-fat diets (45% lard) for 24, 40 and 52 weeks. HFD-feeding induced overt adiposity, altered lipid and insulin homeostasis, increased systemic LGI and adipokine release. HFD-feeding also caused renal upregulation of pro-inflammatory genes, infiltrating macrophages, collagen I protein, increased urinary albumin and NGAL levels. HFD-feeding severely aggravated age-dependent structural changes in the kidney. Remarkably, enhanced amyloid deposition rather than sclerosis was observed. The degree of amyloidosis correlated significantly with body weight. Amyloid deposits stained positive for serum amyloid A (SAA) whose plasma levels were chronically elevated in HFD mice. Our data indicate obesity-induced chronic inflammation as a risk factor for the acceleration of age-dependent renal amyloidosis and functional impairment in mice, and suggest that obesity-enhanced chronic secretion of SAA may be the driving factor behind this process. PMID:26563579

  19. Sucrose and polysaccharide induced obesity in the rat.

    PubMed

    Sclafani, A; Xenakis, S

    1984-02-01

    Adult male rats were fed, in addition to chow and water, solutions (32%) of either sucrose, Polycose (a bland-tasting polysaccharide), or Polycose sweetened with 0.2% saccharin. The solutions were available for two 30-day periods when the rats were 90-120, and 180-210 days of age. A control group received only chow and water during these periods. During the second 30-day test the Polycose and Saccharin- Polycose groups were hyperphagic and gained as much excess weight as did the Sucrose group. The sucrose-fed rats, however, did not overeat relative to the control animals. Adding saccharin to the Polycose failed to increase total caloric intake or weight gain, but did increase Polycose intake and percent carbohydrate intake. The intakes of both Polycose solutions were greater than that of the sucrose solution, although in brief two-bottle preference tests the sucrose solution was preferred over the Polycose and saccharin- Polycose solutions. A similar pattern of results was obtained during the first test period, but the group differences were less pronounced. The findings demonstrate that carbohydrate-induced obesity is not unique to sweet-tasting sugars, but can also be produced by bland-tasting polysaccharides. Sweet taste does increase polysaccharide preference and intake, however.

  20. IL-1β is a key cytokine that induces trypsin upregulation in the influenza virus-cytokine-trypsin cycle.

    PubMed

    Indalao, I L; Sawabuchi, T; Takahashi, E; Kido, H

    2017-01-01

    Severe influenza is characterized by a cytokine storm, and the influenza virus-cytokine-trypsin cycle is one of the important mechanisms of viral multiplication and multiple organ failure. The aim of this study was to define the key cytokine(s) responsible for trypsin upregulation. Mice were infected with influenza virus strain A/Puerto Rico/8/34 (H1N1) or treated individually or with a combination of interleukin-1β, interleukin-6, and tumor necrosis factor α. The levels of these cytokines and trypsin in the lungs were monitored. The neutralizing effects of anti-IL-1β antibodies on cytokine and trypsin expression in human A549 cells and lung inflammation in the infected mice were examined. Infection induced interleukin-1β, interleukin-6, tumor necrosis factor α, and ectopic trypsin in mouse lungs in a dose- and time-dependent manner. Intraperitoneal administration of interleukin-1β combined with other cytokines tended to upregulate trypsin and cytokine expression in the lungs, but the combination without interleukin-1β did not induce trypsin. In contrast, incubation of A549 cells with interleukin-1β alone induced both cytokines and trypsin, and anti-interleukin-1β antibody treatment abrogated these effects. Administration of the antibody in the infected mice reduced lung inflammation area. These findings suggest that IL-1β plays a key role in trypsin upregulation and has a pathological role in multiple organ failure.

  1. Lipoxin A4 Attenuates Obesity-Induced Adipose Inflammation and Associated Liver and Kidney Disease.

    PubMed

    Börgeson, Emma; Johnson, Andrew M F; Lee, Yun Sok; Till, Andreas; Syed, Gulam Hussain; Ali-Shah, Syed Tasadaque; Guiry, Patrick J; Dalli, Jesmond; Colas, Romain A; Serhan, Charles N; Sharma, Kumar; Godson, Catherine

    2015-07-07

    The role of inflammation in obesity-related pathologies is well established. We investigated the therapeutic potential of LipoxinA4 (LXA4:5(S),6(R),15(S)-trihydroxy-7E,9E,11Z,13E,-eicosatetraenoic acid) and a synthetic 15(R)-Benzo-LXA4-analog as interventions in a 3-month high-fat diet (HFD; 60% fat)-induced obesity model. Obesity caused distinct pathologies, including impaired glucose tolerance, adipose inflammation, fatty liver, and chronic kidney disease (CKD). Lipoxins (LXs) attenuated obesity-induced CKD, reducing glomerular expansion, mesangial matrix, and urinary H2O2. Furthermore, LXA4 reduced liver weight, serum alanine-aminotransferase, and hepatic triglycerides. LXA4 decreased obesity-induced adipose inflammation, attenuating TNF-α and CD11c(+) M1-macrophages (MΦs), while restoring CD206(+) M2-MΦs and increasing Annexin-A1. LXs did not affect renal or hepatic MΦs, suggesting protection occurred via attenuation of adipose inflammation. LXs restored adipose expression of autophagy markers LC3-II and p62. LX-mediated protection was demonstrable in adiponectin(-/-) mice, suggesting that the mechanism was adiponectin independent. In conclusion, LXs protect against obesity-induced systemic disease, and these data support a novel therapeutic paradigm for treating obesity and associated pathologies.

  2. Plumbagin sensitizes breast cancer cells to tamoxifen-induced cell death through GRP78 inhibition and Bik upregulation.

    PubMed

    Kawiak, Anna; Domachowska, Anna; Jaworska, Anna; Lojkowska, Ewa

    2017-03-13

    The glucose regulated protein 78 (GRP78) is a major chaperone of the endoplasmic reticulum, and a prosurvival component of the unfolded protein response. GRP78 is upregulated in many types of cancers, including breast cancer. Research has suggested that GRP78 overexpression confers chemoresistance to anti-estrogen agents through a mechanism involving the inhibition of a pro-apoptotic BH3-only protein, Bik. In the present research the role of plumbagin, a naturally occurring naphthoquinone, in GRP78-associated cell death inhibition was examined. The results demonstrated that plumbagin inhibits GRP78 activity and GRP78 inhibition contributes to plumbagin-mediated cell death induction. Furthermore, Bik upregulation was associated with plumbagin-induced cell death and an increase in plumbagin-mediated Bik induction was observed upon GRP78 downregulation. Plumbagin sensitized estrogen-positive breast cancer cells to tamoxifen and the association of GRP78 inhibition and Bik upregulation in plumbagin-mediated cell sensitization was shown. Collectively, the results of this research suggest that plumbagin inhibits the antiapoptotic activity of GRP78 leading to Bik upregulation and apoptosis induction, which contributes to the sensitization of breast cancer cells to tamoxifen.

  3. PMA-induced dissociation of Ku86 from the promoter causes transcriptional up-regulation of histamine H1 receptor

    PubMed Central

    Mizuguchi, Hiroyuki; Miyagi, Kohei; Terao, Takuma; Sakamoto, Noriko; Yamawaki, Yosuke; Adachi, Tsubasa; Ono, Shohei; Sasaki, Yohei; Yoshimura, Yoshiyuki; Kitamura, Yoshiaki; Takeda, Noriaki; Fukui, Hiroyuki

    2012-01-01

    Histamine H1 receptor (H1R) gene is up-regulated in patients with allergic rhinitis, and its expression level strongly correlates with the severity of symptoms. However, the mechanism underlying this remains unknown. Here we report the mechanism of H1R gene up-regulation. The luciferase assay revealed the existence of two promoter regions, A and B1. Two AP-1 and one Ets-1 bound to region A, while Ku86, Ku70, and PARP-1 bound to region B1. Ku86 was responsible for DNA binding and poly(ADP-ribosyl)ated in response to phorbol-12-myristate-13-acetate stimulation, inducing its dissociation from region B1 that is crucial for promoter activity. Knockdown of Ku86 gene enhanced up-regulation of H1R gene expression. Experiments using inhibitors for MEK and PARP-1 indicate that regions A and B1 are downstream regulatory elements of the PKCδ/ERK/PARP-1 signaling pathway. Data suggest a novel mechanism for the up-regulation of H1R gene expression. PMID:23209876

  4. Plumbagin sensitizes breast cancer cells to tamoxifen-induced cell death through GRP78 inhibition and Bik upregulation

    PubMed Central

    Kawiak, Anna; Domachowska, Anna; Jaworska, Anna; Lojkowska, Ewa

    2017-01-01

    The glucose regulated protein 78 (GRP78) is a major chaperone of the endoplasmic reticulum, and a prosurvival component of the unfolded protein response. GRP78 is upregulated in many types of cancers, including breast cancer. Research has suggested that GRP78 overexpression confers chemoresistance to anti-estrogen agents through a mechanism involving the inhibition of a pro-apoptotic BH3-only protein, Bik. In the present research the role of plumbagin, a naturally occurring naphthoquinone, in GRP78-associated cell death inhibition was examined. The results demonstrated that plumbagin inhibits GRP78 activity and GRP78 inhibition contributes to plumbagin-mediated cell death induction. Furthermore, Bik upregulation was associated with plumbagin-induced cell death and an increase in plumbagin-mediated Bik induction was observed upon GRP78 downregulation. Plumbagin sensitized estrogen-positive breast cancer cells to tamoxifen and the association of GRP78 inhibition and Bik upregulation in plumbagin-mediated cell sensitization was shown. Collectively, the results of this research suggest that plumbagin inhibits the antiapoptotic activity of GRP78 leading to Bik upregulation and apoptosis induction, which contributes to the sensitization of breast cancer cells to tamoxifen. PMID:28287102

  5. Hesperidin protects against cyclophosphamide-induced hepatotoxicity by upregulation of PPARγ and abrogation of oxidative stress and inflammation.

    PubMed

    Mahmoud, Ayman M

    2014-09-01

    The most important reason for the non-approval and withdrawal of drugs by the Food and Drug Administration is hepatotoxicity. Therefore, this study was undertaken to evaluate the protective effects of hesperidin against cyclophosphamide (CYP)-induced hepatotoxicity in Wistar rats. The rats received a single intraperitoneal dose of CYP of 200 mg/kg body mass, followed by treatment with hesperidin, orally, at doses of 25 and 50 mg/kg for 11 consecutive days. CYP induced hepatic damage, as evidenced by the significantly elevated levels of serum pro-inflammatory cytokines, serum transaminases, liver lipid peroxidation, and nitric oxide. As a consequence, there was reduced glutathione content, and the activities of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase, were markedly reduced. In addition, CYP administration induced a considerable downregulation of peroxisome proliferator activated receptor gamma (PPARγ) and upregulation of nuclear factor-kappa B (NF-κB) and inducible nitric oxide synthase (iNOS) mRNA expression. Hesperidin, in a dose-dependent manner, rejuvenated the altered markers to an almost normal state. In conclusion, hesperidin showed a potent protective effect against CYP-induced oxidative stress and inflammation leading to hepatotoxicity. The study suggests that hesperidin exerts its protective effect against CYP-induced hepatotoxicity through upregulation of hepatic PPARγ expression and abrogation of inflammation and oxidative stress.

  6. Gas6 induces cancer cell migration and epithelial–mesenchymal transition through upregulation of MAPK and Slug

    SciTech Connect

    Lee, Yunhee; Lee, Mira; Kim, Semi

    2013-04-26

    Highlights: •We investigated the molecular mechanisms underlying Gas6-mediated cancer cell migration. •Gas6 treatment and subsequent Axl activation induce cell migration and EMT via upregulation of Slug. •Slug expression mediated by Gas6 is mainly through c-Jun and ATF-2 in an ERK1/2 and JNK-dependent manner. •The Gas6/Axl-Slug axis may be exploited as a target for anti-cancer metastasis therapy. -- Abstract: Binding of Gas6 to Axl (Gas6/Axl axis) alters cellular functions, including migration, invasion, proliferation, and survival. However, the molecular mechanisms underlying Gas6-mediated cell migration remain poorly understood. In this study, we found that Gas6 induced the activation of JNK and ERK1/2 signaling in cancer cells expressing Axl, resulting in the phosphorylation of activator protein-1 (AP-1) transcription factors c-Jun and ATF-2, and induction of Slug. Depletion of c-Jun or ATF-2 by siRNA attenuated the Gas6-induced expression of Slug. Slug expression was required for cell migration and E-cadherin reduction/vimentin induction induced by Gas6. These results suggest that Gas6 induced cell migration via Slug upregulation in JNK- and ERK1/2-dependent mechanisms. These data provide an important insight into the molecular mechanisms mediating Gas6-induced cell migration.

  7. Diet-Induced Obesity Does Not Alter Tigecycline Treatment Efficacy in Murine Lyme Disease

    PubMed Central

    Pětrošová, Helena; Eshghi, Azad; Anjum, Zoha; Zlotnikov, Nataliya; Cameron, Caroline E.; Moriarty, Tara J.

    2017-01-01

    Obese individuals more frequently suffer from infections, as a result of increased susceptibility to a number of bacterial pathogens. Furthermore, obesity can alter antibiotic treatment efficacy due to changes in drug pharmacokinetics which can result in under-dosing. However, studies on the treatment of bacterial infections in the context of obesity are scarce. To address this research gap, we assessed efficacy of antibiotic treatment in diet-induced obese mice infected with the Lyme disease pathogen, Borrelia burgdorferi. Diet-induced obese C3H/HeN mice and normal-weight controls were infected with B. burgdorferi, and treated during the acute phase of infection with two doses of tigecycline, adjusted to the weights of diet-induced obese and normal-weight mice. Antibiotic treatment efficacy was assessed 1 month after the treatment by cultivating bacteria from tissues, measuring severity of Lyme carditis, and quantifying bacterial DNA clearance in ten tissues. In addition, B. burgdorferi-specific IgG production was monitored throughout the experiment. Tigecycline treatment was ineffective in reducing B. burgdorferi DNA copies in brain. However, diet-induced obesity did not affect antibiotic-dependent bacterial DNA clearance in any tissues, regardless of the tigecycline dose used for treatment. Production of B. burgdorferi-specific IgGs was delayed and attenuated in mock-treated diet-induced obese mice compared to mock-treated normal-weight animals, but did not differ among experimental groups following antibiotic treatment. No carditis or cultivatable B. burgdorferi were detected in any antibiotic-treated group. In conclusion, obesity was associated with attenuated and delayed humoral immune responses to B. burgdorferi, but did not affect efficacy of antibiotic treatment. PMID:28286500

  8. Proinflammatory adipokine leptin mediates disinfection byproduct bromodichloromethane-induced early steatohepatitic injury in obesity

    SciTech Connect

    Das, Suvarthi; Kumar, Ashutosh; Seth, Ratanesh Kumar; Tokar, Erik J.; Kadiiska, Maria B.; Waalkes, Michael P.; Mason, Ronald P.; Chatterjee, Saurabh

    2013-06-15

    Today's developed world faces a major public health challenge in the rise in the obese population and the increased incidence in fatty liver disease. There is a strong association among diet induced obesity, fatty liver disease and development of nonalcoholic steatohepatitis but the environmental link to disease progression remains unclear. Here we demonstrate that in obesity, early steatohepatitic lesions induced by the water disinfection byproduct bromodichloromethane are mediated by increased oxidative stress and leptin which act in synchrony to potentiate disease progression. Low acute exposure to bromodichloromethane (BDCM), in diet-induced obesity produced oxidative stress as shown by increased lipid peroxidation, protein free radical and nitrotyrosine formation and elevated leptin levels. Exposed obese mice showed histopathological signs of early steatohepatitic injury and necrosis. Spontaneous knockout mice for leptin or systemic leptin receptor knockout mice had significantly decreased oxidative stress and TNF-α levels. Co-incubation of leptin and BDCM caused Kupffer cell activation as shown by increased MCP-1 release and NADPH oxidase membrane assembly, a phenomenon that was decreased in Kupffer cells isolated from leptin receptor knockout mice. In obese mice that were BDCM-exposed, livers showed a significant increase in Kupffer cell activation marker CD68 and, increased necrosis as assessed by levels of isocitrate dehydrogenase, events that were decreased in the absence of leptin or its receptor. In conclusion, our results show that exposure to the disinfection byproduct BDCM in diet-induced obesity augments steatohepatitic injury by potentiating the effects of leptin on oxidative stress, Kupffer cell activation and cell death in the liver. - Highlights: ► BDCM acute exposure sensitizes liver to increased free radical stress in obesity. ► BDCM-induced higher leptin contributes to early steatohepatitic lesions. ► Increased leptin mediates protein

  9. Korean Pine Nut Oil Attenuated Hepatic Triacylglycerol Accumulation in High-Fat Diet-Induced Obese Mice.

    PubMed

    Park, Soyoung; Shin, Sunhye; Lim, Yeseo; Shin, Jae Hoon; Seong, Je Kyung; Han, Sung Nim

    2016-01-21

    Korean pine nut oil (PNO) has been reported to influence weight gain and lipid metabolism. We examined whether PNO replacement in a high-fat diet (HFD) can ameliorate HFD-induced hepatic steatosis. Five-week-old male C57BL mice were fed control diets containing 10% of the energy from fat from PNO or soybean oil (SBO) (PC, SC) or HFDs with 45% of the energy from fat, with 10% from PNO or SBO and 35% from lard (PHFD, SHFD), for 12 weeks. Body weight gain and amount of white adipose tissue were lower in PHFD (10% and 18% lower, respectively) compared with SHFD. Hepatic triacylglycerol (TG) level was significantly lower in PHFD than the SHFD (26% lower). PNO consumption upregulated hepatic ACADL mRNA levels. The hepatic PPARG mRNA level was lower in the PC than in the SC. Expression of the sirtuin (SIRT) 3 protein in white adipose tissue was down-regulated in the SHFD and restored in the PHFD to the level in the lean control mice. SIRT 3 was reported to be upregulated under conditions of caloric restriction (CR) and plays a role in regulating mitochondrial function. PNO consumption resulted in lower body fat and hepatic TG accumulation in HFD-induced obesity, which seemed to be associated with the CR-mimetic response.

  10. Korean Pine Nut Oil Attenuated Hepatic Triacylglycerol Accumulation in High-Fat Diet-Induced Obese Mice

    PubMed Central

    Park, Soyoung; Shin, Sunhye; Lim, Yeseo; Shin, Jae Hoon; Seong, Je Kyung; Han, Sung Nim

    2016-01-01

    Korean pine nut oil (PNO) has been reported to influence weight gain and lipid metabolism. We examined whether PNO replacement in a high-fat diet (HFD) can ameliorate HFD-induced hepatic steatosis. Five-week-old male C57BL mice were fed control diets containing 10% of the energy from fat from PNO or soybean oil (SBO) (PC, SC) or HFDs with 45% of the energy from fat, with 10% from PNO or SBO and 35% from lard (PHFD, SHFD), for 12 weeks. Body weight gain and amount of white adipose tissue were lower in PHFD (10% and 18% lower, respectively) compared with SHFD. Hepatic triacylglycerol (TG) level was significantly lower in PHFD than the SHFD (26% lower). PNO consumption upregulated hepatic ACADL mRNA levels. The hepatic PPARG mRNA level was lower in the PC than in the SC. Expression of the sirtuin (SIRT) 3 protein in white adipose tissue was down-regulated in the SHFD and restored in the PHFD to the level in the lean control mice. SIRT 3 was reported to be upregulated under conditions of caloric restriction (CR) and plays a role in regulating mitochondrial function. PNO consumption resulted in lower body fat and hepatic TG accumulation in HFD-induced obesity, which seemed to be associated with the CR-mimetic response. PMID:26805879

  11. Defective regulation of POMC precedes hypothalamic inflammation in diet-induced obesity

    PubMed Central

    Souza, Gabriela F. P.; Solon, Carina; Nascimento, Lucas F.; De-Lima-Junior, Jose C.; Nogueira, Guilherme; Moura, Rodrigo; Rocha, Guilherme Z.; Fioravante, Milena; Bobbo, Vanessa; Morari, Joseane; Razolli, Daniela; Araujo, Eliana P.; Velloso, Licio A.

    2016-01-01

    Obesity is the result of a long-term positive energy balance in which caloric intake overrides energy expenditure. This anabolic state results from the defective activity of hypothalamic neurons involved in the sensing and response to adiposity. However, it is currently unknown what the earliest obesity-linked hypothalamic defect is and how it orchestrates the energy imbalance present in obesity. Using an outbred model of diet-induced obesity we show that defective regulation of hypothalamic POMC is the earliest marker distinguishing obesity-prone from obesity-resistant mice. The early inhibition of hypothalamic POMC was sufficient to transform obesity-resistant in obesity-prone mice. In addition, the post-prandial change in the blood level of β-endorphin, a POMC-derived peptide, correlates with body mass gain in rodents and humans. Taken together, these results suggest that defective regulation of POMC expression, which leads to a change of β-endorphin levels, is the earliest hypothalamic defect leading to obesity. PMID:27373214

  12. Obesity May Not Induce Dynamic Stability Disadvantage during Overground Walking among Young Adults.

    PubMed

    Liu, Zhong-Qi; Yang, Feng

    2017-01-01

    Obesity has been related to postural instability during static standing. It remains unknown how obesity influences stability during dynamic movements like gait. The primary aim of this study was to investigate the effects of obesity on dynamic gait stability control in young adults during gait. Forty-four young adults (21 normal-weight and 23 obese) participated in this study. Participants walked five times at their self-selected gait speeds on a linear walkway. Their full-body kinematics were gathered by a motion capture system. Compared with normal-weight group, individuals with obesity walked more slowly with a shorter but wider step. People with obesity also spent an elongated double stance phase than those with normal weight. A reduced gait speed decreases the body center of mass's velocity relative to the base of support, leading to a reduction in dynamic stability. On the other hand, a shortened step in accompanying with a less backward-leaning trunk has the potential to bring the center of mass closer to the base of support, resulting in an increase in dynamic stability. As the result of these adaptive changes to the gait pattern, dynamic gait stability among people with obesity did not significantly differ from the one among people with normal weight. Obesity seems to not be inducing dynamic stability disadvantage in young adults during level overground walking. These findings could provide insight into the mechanisms of stability control among people affected by obesity during dynamic locomotion.

  13. Obesity May Not Induce Dynamic Stability Disadvantage during Overground Walking among Young Adults

    PubMed Central

    Liu, Zhong-Qi; Yang, Feng

    2017-01-01

    Obesity has been related to postural instability during static standing. It remains unknown how obesity influences stability during dynamic movements like gait. The primary aim of this study was to investigate the effects of obesity on dynamic gait stability control in young adults during gait. Forty-four young adults (21 normal-weight and 23 obese) participated in this study. Participants walked five times at their self-selected gait speeds on a linear walkway. Their full-body kinematics were gathered by a motion capture system. Compared with normal-weight group, individuals with obesity walked more slowly with a shorter but wider step. People with obesity also spent an elongated double stance phase than those with normal weight. A reduced gait speed decreases the body center of mass’s velocity relative to the base of support, leading to a reduction in dynamic stability. On the other hand, a shortened step in accompanying with a less backward-leaning trunk has the potential to bring the center of mass closer to the base of support, resulting in an increase in dynamic stability. As the result of these adaptive changes to the gait pattern, dynamic gait stability among people with obesity did not significantly differ from the one among people with normal weight. Obesity seems to not be inducing dynamic stability disadvantage in young adults during level overground walking. These findings could provide insight into the mechanisms of stability control among people affected by obesity during dynamic locomotion. PMID:28085914

  14. JNK-dependent Atg4 upregulation mediates asperphenamate derivative BBP-induced autophagy in MCF-7 cells

    SciTech Connect

    Li, Yanchun; Luo, Qiyu; Yuan, Lei; Miao, Caixia; Mu, Xiaoshuo; Xiao, Wei; Li, Jianchun; Sun, Tiemin; Ma, Enlong

    2012-08-15

    N-Benzoyl-O-(N′-(1-benzyloxycarbonyl-4-piperidiylcarbonyl) -D-phenylalanyl)-D-phenylalaninol (BBP), a novel synthesized asperphenamate derivative with the increased solubility, showed growth inhibitory effect on human breast carcinoma MCF-7 cells in a time- and concentration-dependent manner. The growth inhibitory effect of BBP was associated with induction of autophagy, which was demonstrated by the development of acidic vesicular organelles, cleavage of LC3 and upregulation of Atg4 in BBP-treated MCF-7 cells. Since the application of Atg4 siRNA totally blocked the cleavage of LC3, we demonstrated a central role of Atg4 in BBP-induced autophagy. The further studies showed that BBP increased the levels of reactive oxygen species (ROS), and pretreatment with NAC effectively blocked the accumulation of ROS, autophagy and growth inhibition triggered by BBP. Moreover, BBP induced the activation of JNK, and JNK inhibitor SP600125 reversed autophagy, the increase of Atg4 levels, conversion of LC3 and growth inhibition induced by BBP. Knockdown of JNK by siRNA efficiently inhibited ROS production and autophagy, but antioxidant NAC failed to block JNK activation induced by BBP, indicating that JNK activation may be a upstream signaling of ROS and should be a core component in BBP-induced autophagic signaling pathway. These results suggest that BBP produces its growth inhibitory effect through induction of the autophagic cell death in MCF-7 cells, which is modulated by a JNK-dependent Atg4 upregulation involving ROS production. -- Highlights: ► Asperphenamate derivative BBP with increased solubility was synthesized. ► BBP selectively inhibited the growth of human breast tumor cells. ► The growth inhibitory effect of BBP was associated with induction of autophagy. ► JNK-dependent Atg4 upregulation mediated BBP-induced autophagy.

  15. Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle

    PubMed Central

    2013-01-01

    Background In the present study, we tested the hypothesis that carnitine supplementation counteracts obesity-induced muscle fiber transition from type I to type II. Methods 24 obese Zucker rats were randomly divided into two groups of 12 rats each (obese control, obese carnitine) and 12 lean Zucker rats were selected for lean control group. A control diet was given to both control groups and a carnitine supplemented diet (3 g/kg diet) was given to obese carnitine group for 4 wk. Components of the muscle fiber transformation in skeletal muscle were examined. Results The plasma level of carnitine were lower in the obese control group compared to the lean control group and higher in the obese carnitine group than in the other groups (P < 0.05). Plasma concentrations of triglycerides and non-esterified fatty acids were increased in obese animals compared to lean animals and the obese carnitine group had lower level compared to the obese control group (P < 0.05). The obese carnitine group had an increased number of type I muscle fibers and higher mRNA levels of type I fiber-specific myosin heavy chain, regulators of muscle fiber transition and of genes involved in carnitine uptake, fatty acid transport, β-oxidation, angiogenesis, tricarboxylic acid cycle and thermo genesis in M. rectus femoris compared to the other groups (P < 0.05). Conclusion The results demonstrate that carnitine supplementation to obese Zucker a rat counteracts the obesity-induced muscle fiber transition and restores the muscle oxidative metabolic phenotype. Carnitine supplementation is supposed to be beneficial for the treatment of elevated levels of plasma lipids during obesity or diabetes. PMID:23842456

  16. Preventing High Fat Diet-induced Obesity and Improving Insulin Sensitivity through Neuregulin 4 Gene Transfer

    PubMed Central

    Ma, Yongjie; Gao, Mingming; Liu, Dexi

    2016-01-01

    Neuregulin 4 (NRG4), an epidermal growth factor-like signaling molecule, plays an important role in cell-to-cell communication during tissue development. Its function to regulate energy metabolism has recently been reported. This current study was designed to assess the preventive and therapeutic effects of NRG4 overexpression on high fat diet (HFD)-induced obesity. Using the hydrodynamic gene transfer method, we demonstrate that Nrg4 gene transfer in mice suppressed the development of diet-induced obesity, but did not affect pre-existing adiposity and body weight in obese mice. Nrg4 gene transfer curbed HFD-induced hepatic steatosis by inhibiting lipogenesis and PPARγ-mediated lipid storage. Concurrently, overexpression of NRG4 reduced chronic inflammation in both preventive and treatment studies, evidenced by lower mRNA levels of macrophage marker genes including F4/80, Cd68, Cd11b, Cd11c, and macrophage chemokine Mcp1, resulting in improved insulin sensitivity. Collectively, these results demonstrate that overexpression of the Nrg4 gene by hydrodynamic gene delivery prevents HFD-induced weight gain and fatty liver, alleviates obesity-induced chronic inflammation and insulin resistance, and supports the health benefits of NRG4 in managing obesity and obesity-associated metabolic disorders. PMID:27184920

  17. Efficacy of Kaempferia parviflora in a mouse model of obesity-induced dermatopathy.

    PubMed

    Hidaka, Moeko; Horikawa, Kazumasa; Akase, Tomoko; Makihara, Hiroko; Ogami, Takatoshi; Tomozawa, Hiroshi; Tsubata, Masahito; Ibuki, Ai; Matsumoto, Yutaka

    2017-01-01

    Obesity results from excessive energy intake and physical inactivity, and predisposes one to various diseases. One of these reasons is that enlargement of adipocytes raises the lipid metabolic abnormalities that affect various organs. The skin is one such organ, and it has been reported that subcutaneous adipocyte cells secrete various factors and these factors are involved in reduction of dermal collagen fibers and fragility of the skin in obesity. The present study explored the efficacy of Kaempferia parviflora (KP) in preventing obesity-induced dermatopathy. We used Tsumura Suzuki obese diabetes (TSOD) mice as an obesity model. TSOD mice were fed a standard diet (MF) mixed with either an ethanol extract from KP (KPE), polymethoxyflavonoid-rich extract from KP (PMF), or polymethoxyflavonoid-poor extract from KP (X). We then evaluated the effect of these three KP fractions on aging-like skin damage induced by UVB irradiation. KPE and PMF caused a significant decrease of mouse body weight, and suppressed the increase in the thickness of the subcutaneous fat layer. In addition, KPE shifted the frequency of subcutaneous adipocyte sizes towards smaller cells possibly via its polypharmacological actions. Scanning electron microscopy revealed that the stereostructure of the collagenous fibers in the dermis was better retained in the KPE and PMF groups, in that order. These results offer the first evidence that KPE can attenuate obesity-induced dermatopathy more effectively than PMF, suggesting that KPE (or KP) might be a candidate supplement for preventing obesity-related skin disorders.

  18. Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells.

    PubMed

    Yun, Sun-Mi; Woo, Sang Hyeok; Oh, Sang Taek; Hong, Sung-Eun; Choe, Tae-Boo; Ye, Sang-Kyu; Kim, Eun-Kyu; Seong, Min Ki; Kim, Hyun-A; Noh, Woo Chul; Lee, Jin Kyung; Jin, Hyeon-Ok; Lee, Yun-Han; Park, In-Chul

    2016-02-15

    Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells.

  19. Individual Differences in Cue-Induced Motivation and Striatal Systems in Rats Susceptible to Diet-Induced Obesity.

    PubMed

    Robinson, Mike J F; Burghardt, Paul R; Patterson, Christa M; Nobile, Cameron W; Akil, Huda; Watson, Stanley J; Berridge, Kent C; Ferrario, Carrie R

    2015-08-01

    Pavlovian cues associated with junk-foods (caloric, highly sweet, and/or fatty foods), like the smell of brownies, can elicit craving to eat and increase the amount of food consumed. People who are more susceptible to these motivational effects of food cues may have a higher risk for becoming obese. Further, overconsumption of junk-foods leading to the development of obesity may itself heighten attraction to food cues. Here, we used a model of individual susceptibility to junk-foods diet-induced obesity to determine whether there are pre-existing and/or diet-induced increases in attraction to and motivation for sucrose-paired cues (ie, incentive salience or 'wanting'). We also assessed diet- vs obesity-associated alterations in mesolimbic function and receptor expression. We found that rats susceptible to diet-induced obesity displayed heightened conditioned approach prior to the development of obesity. In addition, after junk-food diet exposure, those rats that developed obesity also showed increased willingness to gain access to a sucrose cue. Heightened 'wanting' was not due to individual differences in the hedonic impact ('liking') of sucrose. Neurobiologically, Mu opioid receptor mRNA expression was lower in striatal 'hot-spots' that generate eating or hedonic impact only in those rats that became obese. In contrast, prolonged exposure to junk-food resulted in cross-sensitization to amphetamine-induced locomotion and downregulation of striatal D2R mRNA regardless of the development of obesity. Together these data shed light on individual differences in behavioral and neurobiological consequences of exposure to junk-food diets and the potential contribution of incentive sensitization in susceptible individuals to greater food cue-triggered motivation.

  20. Diet-induced obesity reprograms the inflammatory response of the murine lung to inhaled endotoxin

    SciTech Connect

    Tilton, Susan C.; Waters, Katrina M.; Karin, Norman J.; Webb-Robertson, Bobbie-Jo M.; Zangar, Richard C.; Lee, K. Monica; Bigelow, Diana J.; Pounds, Joel G.; Corley, Richard A.

    2013-03-01

    The co-occurrence of environmental factors is common in complex human diseases and, as such, understanding the molecular responses involved is essential to determine risk and susceptibility to disease. We have investigated the key biological pathways that define susceptibility for pulmonary infection during obesity in diet-induced obese (DIO) and regular weight (RW) C57BL/6 mice exposed to inhaled lipopolysaccharide (LPS). LPS induced a strong inflammatory response in all mice as indicated by elevated cell counts of macrophages and neutrophils and levels of proinflammatory cytokines (MDC, MIP-1γ, IL-12, RANTES) in the bronchoalveolar lavage fluid. Additionally, DIO mice exhibited 50% greater macrophage cell counts, but decreased levels of the cytokines, IL-6, TARC, TNF-α, and VEGF relative to RW mice. Microarray analysis of lung tissue showed over half of the LPS-induced expression in DIO mice consisted of genes unique for obese mice, suggesting that obesity reprograms how the lung responds to subsequent insult. In particular, we found that obese animals exposed to LPS have gene signatures showing increased inflammatory and oxidative stress response and decreased antioxidant capacity compared with RW. Because signaling pathways for these responses can be common to various sources of environmentally induced lung damage, we further identified biomarkers that are indicative of specific toxicant exposure by comparing gene signatures after LPS exposure to those from a parallel study with cigarette smoke. These data show obesity may increase sensitivity to further insult and that co-occurrence of environmental stressors result in complex biosignatures that are not predicted from analysis of individual exposures. - Highlights: ► Obesity modulates inflammatory markers in BAL fluid after LPS exposure. ► Obese animals have a unique transcriptional signature in lung after LPS exposure. ► Obesity elevates inflammatory stress and reduces antioxidant capacity in the lung

  1. The Vibrio cholerae Pst2 phosphate transport system is upregulated in biofilms and contributes to biofilm-induced hyperinfectivity.

    PubMed

    Mudrak, Benjamin; Tamayo, Rita

    2012-05-01

    Vibrio cholerae is the causative agent of the deadly diarrheal disease cholera. As part of its life cycle, V. cholerae persists in marine environments, where it forms surface-attached communities commonly described as biofilms. Evidence indicates that these biofilms constitute the infectious form of the pathogen during outbreaks. Previous work has shown that biofilm-derived V. cholerae cells, even when fully dispersed from the biofilm matrix, are vastly more infectious than planktonic (free-living) cells. Here, we sought to identify factors that contribute to biofilm-induced hyperinfectivity in V. cholerae, and we present evidence for one aspect of the molecular basis of this phenotype. We identified proteins upregulated during growth in biofilms and determined their contributions to the hyperinfectivity phenotype. We found that PstS2, the periplasmic component of the Pst2 phosphate uptake system, was enriched in biofilms. Another gene in the pst2 locus was transcriptionally upregulated in biofilms. Using the infant mouse model, we found that mutation of two pst2 components resulted in impaired colonization. Importantly, deletion of the Pst2 inner membrane complex caused a greater colonization defect after growth in a biofilm compared to shaking culture. Based on these data, we propose that V. cholerae cells in biofilms upregulate the Pst2 system and therefore gain an advantage upon entry into the host. Further characterization of factors contributing to biofilm-induced hyperinfectivity in V. cholerae will improve our understanding of the transmission of the bacteria from natural aquatic habitats to the human host.

  2. Protracted treatment with MDMA induces heteromeric nicotinic receptor up-regulation in the rat brain: an autoradiography study.

    PubMed

    Ciudad-Roberts, Andrés; Camarasa, Jorge; Pubill, David; Escubedo, Elena

    2014-08-04

    Previous studies indicate that 3,4-methylenedioxy-methamphetamine (MDMA, ecstasy) can induce a heteromeric nicotinic acetylcholine receptor (nAChR, mainly of α4β2 subtype) up-regulation. In this study we treated male Sprague-Dawley rats twice-daily for 10 days with either saline or MDMA (7 mg/kg) and sacrificed them the day after to perform [(125)I]Epibatidine binding autoradiograms on serial coronal slices. MDMA induced significant increases in nAChR density in the substantia nigra, ventral tegmental area, nucleus accumbens, olfactory tubercle, anterior caudate-putamen, somatosensory, motor, auditory and retrosplenial cortex, laterodorsal thalamus nuclei, amygdala, postsubiculum and pontine nuclei. These increases ranged from 3% (retrosplenial cortex) to 30 and 34% (amygdala and substantia nigra). No increased α4 subunit immunoreactivity was found in up-regulated areas compared with saline-treated rats, suggesting a post-translational mechanism as occurs with nicotine. The heteromeric nAChR up-regulation in certain areas could account, at least in part, for the reinforcing, sensitizing and psychiatric disorders observed after long-term consumption of MDMA.

  3. TWIST1 induces MMP3 expression through up-regulating DNA hydroxymethylation and promotes catabolic responses in human chondrocytes

    PubMed Central

    Hasei, Joe; Teramura, Takeshi; Takehara, Toshiyuki; Onodera, Yuta; Horii, Takuro; Olmer, Merissa; Hatada, Izuho; Fukuda, Kanji; Ozaki, Toshifumi; Lotz, Martin K.; Asahara, Hiroshi

    2017-01-01

    The objective was to investigate the levels of TWIST1 in normal and OA cartilage and examine its role in regulating gene expression in chondrocytes. Human cartilage tissues and chondrocytes were obtained at autopsy from normal knee joints and from OA-affected joints at the time of total knee arthroplasty. TWIST1 expression was increased in human OA knee cartilage compared to normal knee cartilage. TWIST1 induced matrix metalloproteinase 3 (MMP3) expression without direct binding to MMP3 promoter and increased the 5-hydroxymethylcytosine (5hmC) level at the MMP3 promoter. The effect of TWIST1 on expression of TET family (TET1, 2 and 3) was measured in stable TWIST1 transfected TC28 cells, and TET1 expression was up-regulated. TWIST1 dependent upregulation of Mmp3 expression was suppressed in Tet triple KO fibroblast derived from mouse ES cells. Increased TWIST1 expression is a feature of OA-affected cartilage. We identified a novel mechanism of catabolic reaction where TWIST1 up-regulates MMP3 expression by enriching 5hmC levels at the MMP3 promoter via TET1 induction. These findings implicate TWIST1 as an important factor regulating OA related gene expression. Clarifying epigenetic mechanisms of 5hmC induced by TWIST1 is a critical molecule to understanding OA pathogenesis. PMID:28220902

  4. Diet-induced obesity induces endoplasmic reticulum stress and insulin resistance in the amygdala of rats☆

    PubMed Central

    Castro, Gisele; C. Areias, Maria Fernanda; Weissmann, Lais; Quaresma, Paula G.F.; Katashima, Carlos K.; Saad, Mario J.A.; Prada, Patricia O.

    2013-01-01

    Insulin acts in the hypothalamus, decreasing food intake (FI) by the IR/PI3K/Akt pathway. This pathway is impaired in obese animals and endoplasmic reticulum (ER) stress and low-grade inflammation are possible mechanisms involved in this impairment. Here, we highlighted the amygdala as an important brain region for FI regulation in response to insulin. This regulation was dependent on PI3K/AKT pathway similar to the hypothalamus. Insulin was able to decrease neuropeptide Y (NPY) and increase oxytocin mRNA levels in the amygdala via PI3K, which may contribute to hypophagia. Additionally, obese rats did not reduce FI in response to insulin and AKT phosphorylation was decreased in the amygdala, suggesting insulin resistance. Insulin resistance was associated with ER stress and low-grade inflammation in this brain region. The inhibition of ER stress with PBA reverses insulin action/signaling, decreases NPY and increases oxytocin mRNA levels in the amygdala from obese rats, suggesting that ER stress is probably one of the mechanisms that induce insulin resistance in the amygdala. PMID:24251109

  5. MyomiRs as Markers of Insulin Resistance and Decreased Myogenesis in Skeletal Muscle of Diet-Induced Obese Mice

    PubMed Central

    Frias, Flávia de Toledo; de Mendonça, Mariana; Martins, Amanda Roque; Gindro, Ana Flávia; Cogliati, Bruno; Curi, Rui; Rodrigues, Alice Cristina

    2016-01-01

    High-fat diet (HFD) feeding causes insulin resistance (IR) in skeletal muscle of mice, which affects skeletal muscle metabolism and function. The involvement of muscle-specific microRNAs in the evolution of skeletal muscle IR during 4, 8, and 12 weeks in HFD-induced obese mice was investigated. After 4 weeks in HFD, mice were obese, hyperglycemic, and hyperinsulinemic; however, their muscles were responsive to insulin stimuli. Expressions of MyomiRs (miR-1, miR-133a, and miR-206) measured in soleus muscles were not different from those found in control mice. After 8 weeks of HFD feeding, glucose uptake was lower in skeletal muscle from obese mice compared to control mice, and we observed a significant decrease in miR-1a in soleus muscle when compared to HFD for 4 weeks. miR-1a expression continued to decay within time. After 12 weeks of HFD, miR-133a expression was upregulated when compared to the control group. Expression of miR-1a was negatively correlated with glycemia and positively correlated with the constant rate of plasma glucose disappearance. Pioglitazone treatment could not reverse decreases of miR-1a levels induced by HFD. Targets of myomiRs involved in insulin-growth factor (IGF)-1 pathway, such as Igf-1, Irs-1, Rheb, and follistatin, were reduced after 12 weeks in HFD and Mtor increased, when compared to the control or HFD for 4 or 8 weeks. These findings suggest for the first time that miR-1 may be a marker of the development of IR in skeletal muscle. Evidence was also presented that impairment in myomiRs expression contributes to decreased myogenesis and skeletal muscle growth reported in diabetes. PMID:27445979

  6. Autoimmunity to HSP60 during diet induced obesity in mice

    PubMed Central

    Şelli, M E; Wick, G; Wraith, D C; Newby, A C

    2017-01-01

    Adaptive immunity has been implicated in adipose tissue inflammation, obesity and its adverse metabolic consequences. No obesity-related autoantigen has yet been identified, although heat shock protein 60 (HSP60) has been implicated in other autoimmune diseases. We investigated whether feeding a high-fat diet to C57BL/6J mice would cause autoimmunity to HSP60 and whether immunomodulation with peptides from HSP60 would reverse the resulting obesity or metabolic dysfunction. Obese mice had higher circulating levels of HSP60 associated with increased T-lymphocyte proliferation responses and the emergence of circulating IgG1 and IgG2c antibody levels against HSP60. Treatment with escalating doses of a mixture of three proven immunomodulatory HSP60 peptides did not reduce weight but completely reversed the increase in VLDL/LDL levels and partially reversed the glucose intolerance in obese mice. Obese mice mount an autoimmune response to HSP60, which partly underlies the resulting metabolic disturbances. PMID:27899808

  7. Apigenin Ameliorates Dyslipidemia, Hepatic Steatosis and Insulin Resistance by Modulating Metabolic and Transcriptional Profiles in the Liver of High-Fat Diet-Induced Obese Mice.

    PubMed

    Jung, Un Ju; Cho, Yun-Young; Choi, Myung-Sook

    2016-05-19

    Several in vitro and in vivo studies have reported the anti-inflammatory, anti-diabetic and anti-obesity effects of the flavonoid apigenin. However, the long-term supplementary effects of low-dose apigenin on obesity are unclear. Therefore, we investigated the protective effects of apigenin against obesity and related metabolic disturbances by exploring the metabolic and transcriptional responses in high-fat diet (HFD)-induced obese mice. C57BL/6J mice were fed an HFD or apigenin (0.005%, w/w)-supplemented HFD for 16 weeks. In HFD-fed mice, apigenin lowered plasma levels of free fatty acid, total cholesterol, apolipoprotein B and hepatic dysfunction markers and ameliorated hepatic steatosis and hepatomegaly, without altering food intake and adiposity. These effects were partly attributed to upregulated expression of genes regulating fatty acid oxidation, tricarboxylic acid cycle, oxidative phosphorylation, electron transport chain and cholesterol homeostasis, downregulated expression of lipolytic and lipogenic genes and decreased activities of enzymes responsible for triglyceride and cholesterol ester synthesis in the liver. Moreover, apigenin lowered plasma levels of pro-inflammatory mediators and fasting blood glucose. The anti-hyperglycemic effect of apigenin appeared to be related to decreased insulin resistance, hyperinsulinemia and hepatic gluconeogenic enzymes activities. Thus, apigenin can ameliorate HFD-induced comorbidities via metabolic and transcriptional modulations in the liver.

  8. Apigenin Ameliorates Dyslipidemia, Hepatic Steatosis and Insulin Resistance by Modulating Metabolic and Transcriptional Profiles in the Liver of High-Fat Diet-Induced Obese Mice

    PubMed Central

    Jung, Un Ju; Cho, Yun-Young; Choi, Myung-Sook

    2016-01-01

    Several in vitro and in vivo studies have reported the anti-inflammatory, anti-diabetic and anti-obesity effects of the flavonoid apigenin. However, the long-term supplementary effects of low-dose apigenin on obesity are unclear. Therefore, we investigated the protective effects of apigenin against obesity and related metabolic disturbances by exploring the metabolic and transcriptional responses in high-fat diet (HFD)-induced obese mice. C57BL/6J mice were fed an HFD or apigenin (0.005%, w/w)-supplemented HFD for 16 weeks. In HFD-fed mice, apigenin lowered plasma levels of free fatty acid, total cholesterol, apolipoprotein B and hepatic dysfunction markers and ameliorated hepatic steatosis and hepatomegaly, without altering food intake and adiposity. These effects were partly attributed to upregulated expression of genes regulating fatty acid oxidation, tricarboxylic acid cycle, oxidative phosphorylation, electron transport chain and cholesterol homeostasis, downregulated expression of lipolytic and lipogenic genes and decreased activities of enzymes responsible for triglyceride and cholesterol ester synthesis in the liver. Moreover, apigenin lowered plasma levels of pro-inflammatory mediators and fasting blood glucose. The anti-hyperglycemic effect of apigenin appeared to be related to decreased insulin resistance, hyperinsulinemia and hepatic gluconeogenic enzymes activities. Thus, apigenin can ameliorate HFD-induced comorbidities via metabolic and transcriptional modulations in the liver. PMID:27213439

  9. Free fatty acids and IL-6 induce adipocyte galectin-3 which is increased in white and brown adipose tissues of obese mice.

    PubMed

    Krautbauer, Sabrina; Eisinger, Kristina; Hader, Yvonne; Buechler, Christa

    2014-10-01

    Galectin-3 regulates immune cell function and clearance of advanced glycation end products. Galectin-3 is increased in serum of obese humans and mice and most studies suggest that this protein protects from inflammation in metabolic diseases. Current data show that galectin-3 is markedly elevated in the liver, subcutaneous and intra-abdominal fat depots of mice fed a high fat diet and ob/ob mice. Galectin-3 is also increased in brown adipose tissues of these animals and immunohistochemistry confirms higher levels in adipocytes. Raised galectin-3 in obese white adipocytes has been described in the literature and regulation of adipocyte galectin-3 by metabolites with a role in obesity has been analyzed. Galectin-3 is expressed in 3T3-L1 fibroblasts and human preadipocytes and is modestly induced in mature adipocytes. In 3T3-L1 adipocytes galectin-3 is localized in the cytoplasm and is also detected in cell supernatants. Glucose does not alter soluble galectin-3. Lipopolysaccharide has no effect while TNF reduces and IL-6 raises this lectin in cell supernatants. Palmitate and oleate modestly elevate soluble galectin-3. Differentiation of 3T3-L1 cells in the presence of 100 μM and 200 μM linoleate induces soluble galectin-3 and cellular levels are upregulated by the higher concentration. Current data suggest that free fatty acids and IL-6 increase galectin-3 in adipocytes and thereby may contribute to higher levels in obesity.

  10. Ethanol Upregulates Glucocorticoid-induced Leucine Zipper Expression and Modulates Cellular Inflammatory Responses in Lung Epithelial Cells

    PubMed Central

    Gomez, Marla; Raju, Sammeta V.; Viswanathan, Anand; Painter, Richard G.; Bonvillain, Ryan; Byrne, Patrick; Nguyen, Doan H.; Bagby, Gregory J.; Kolls, Jay K.; Nelson, Steve; Wang, Guoshun

    2010-01-01

    Alcohol abuse is associated with immunosuppressive and infectious sequelae. Particularly, alcoholics are more susceptible to pulmonary infections. In this report, gene transcriptional profiles of primary human airway epithelial cells, exposed to varying doses of alcohol (0, 50 and 100 mM), were obtained. Comparison of gene transcription levels between 0 mM and 50 mM alcohol treatments resulted in 2 genes being up-regulated and 16 genes down-regulated by at least two-fold. Moreover, 0 mM and 100 mM alcohol exposure led to the up-regulation of 14 genes and down-regulation of 157 genes. Among the up-regulated genes, glucocorticoid-induced leucine zipper (GILZ) responded to alcohol in a dose-dependent manner. Moreover, GILZ protein levels also correlated with this transcriptional pattern. Lentiviral expression of GILZ siRNA in human airway epithelial cells diminished the alcohol-induced upregulation, confirming that GILZ is indeed an alcohol-responsive gene. Gene-silencing of GILZ in A549 cells resulted in secretion of significantly higher amounts of inflammatory cytokines in response to IL-1β stimulation. The GILZ-silenced cells were more resistant to alcohol-mediated suppression of cytokine secretion. Further data demonstrated that the glucocorticoid receptor is involved in the regulation of GILZ by alcohol. Because GILZ is a key glucocorticoid-responsive factor mediating the anti-inflammatory and immunosuppressive actions of steroids, we propose that similar signaling pathways may play a role in the anti-inflammatory and immunosuppressive effects of alcohol. PMID:20382889

  11. Tolfenamic acid downregulates BACE1 and protects against lead-induced upregulation of Alzheimer's disease related biomarkers.

    PubMed

    Adwan, Lina; Subaiea, Gehad M; Zawia, Nasser H

    2014-04-01

    Environmental exposure to lead (Pb) early in life results in a latent upregulation of genes and products associated with Alzheimer's disease (AD), particularly the plaque forming protein amyloid beta (Aβ). Furthermore, animals exposed to Pb as infants develop cognitive decline and memory impairments in old age. Studies from our lab demonstrated that tolfenamic acid lowers the levels of the amyloid β precursor protein (APP) and its aggregative cleavage product Aβ by inducing the degradation of the transcription factor specificity protein 1 (Sp1). These changes were accompanied by cognitive improvement in transgenic APP knock-in mice. In this study, we examined the effects of tolfenamic acid on beta site APP cleaving enzyme 1 (BACE1) which is responsible for Aβ production and tested its ability to reverse Pb-induced upregulation in the amyloidogenic pathway. Mice were administered tolfenamic acid for one month and BACE1 gene expression as well as its enzymatic activity were analyzed in the cerebral cortex. Tolfenamic acid was also tested for its ability to reverse changes in Sp1, APP and Aβ that were upregulated by Pb in vitro. Differentiated SH-SY5Y neuroblastoma cells were either left unexposed, or sequentially exposed to Pb followed by tolfenamic acid. Our results show that tolfenamic acid reduced BACE1 gene expression and enzyme activity in mice. In neuroblastoma cells, Pb upregulated Sp1, APP and Aβ, while tolfenamic acid lowered their expression. These results along with previous data from our lab provide evidence that tolfenamic acid, a drug that has been used for decades for migraine, represents a candidate which can reduce the pathology of AD and may mitigate the damage of environmental risk factors associated with this disease.

  12. Leptin Induces Hypertension and Endothelial Dysfunction via Aldosterone-Dependent Mechanisms in Obese Female Mice.

    PubMed

    Huby, Anne-Cécile; Otvos, Laszlo; Belin de Chantemèle, Eric J

    2016-05-01

    Obesity is a major risk factor for cardiovascular disease in males and females. Whether obesity triggers cardiovascular disease via similar mechanisms in both the sexes is, however, unknown. In males, the adipokine leptin highly contributes to obesity-related cardiovascular disease by increasing sympathetic activity. Females secrete 3× to 4× more leptin than males, but do not exhibit high sympathetic tone with obesity. Nevertheless, females show inappropriately high aldosterone levels that positively correlate with adiposity and blood pressure (BP). We hypothesized that leptin induces hypertension and endothelial dysfunction via aldosterone-dependent mechanisms in females. Leptin control of the cardiovascular function was analyzed in female mice sensitized to leptin via the deletion of protein tyrosine phosphatase 1b (knockout) and in agouti yellow obese hyperleptinemic mice (Ay). Hypersensitivity to leptin (wild-type, 115 ± 2; protein tyrosine phosphatase 1b knockout, 124 ± 2 mm Hg; P<0.05) and obesity elevated BP (a/a, 113 ± 1; Ay, 128 ± 7 mm Hg; P<0.05) and impaired endothelial function. Chronic leptin receptor antagonism restored BP and endothelial function in protein tyrosine phosphatase 1b knockout and Ay mice. Hypersensitivity to leptin and obesity reduced BP response to ganglionic blockade in both strains and plasma catecholamine levels in protein tyrosine phosphatase 1b knockout mice. Hypersensitivity to leptin and obesity significantly increased plasma aldosterone levels and adrenal CYP11B2 expression. Chronic leptin receptor antagonism reduced aldosterone levels. Furthermore, chronic leptin and mineralocorticoid receptor blockade reduced BP and improved endothelial function in both leptin-sensitized and obese hyperleptinemic female mice. Together, these data demonstrate that leptin induces hypertension and endothelial dysfunction via aldosterone-dependent mechanisms in female mice and suggest that obesity leads to cardiovascular disease via sex

  13. Leptin Induces Hypertension and Endothelial Dysfunction via Aldosterone-Dependent Mechanisms in Obese Female Mice

    PubMed Central

    Huby, Anne-Cecile; Otvos, Laszlo; Belin de Chantemèle, Eric J.

    2016-01-01

    Obesity is a major risk factor for cardiovascular disease in males and females. Whether obesity triggers cardiovascular disease via similar mechanisms in both the sexes is, however, unknown. In males, the adipokine leptin highly contributes to obesity-related cardiovascular disease by increasing sympathetic activity. Females secrete 3× to 4× more leptin than males, but do not exhibit high sympathetic tone with obesity. Nevertheless, females show inappropriately high aldosterone levels that positively correlate with adiposity and blood pressure (BP). We hypothesized that leptin induces hypertension and endothelial dysfunction via aldosterone-dependent mechanisms in females. Leptin control of the cardiovascular function was analyzed in female mice sensitized to leptin via the deletion of protein tyrosine phosphatase 1b (knockout) and in agouti yellow obese hyperleptinemic mice (Ay). Hypersensitivity to leptin (wild-type, 115±2; protein tyrosine phosphatase 1b knockout, 124±2 mm Hg; P<0.05) and obesity elevated BP (a/a, 113±1; Ay, 128±7 mm Hg; P<0.05) and impaired endothelial function. Chronic leptin receptor antagonism restored BP and endothelial function in protein tyrosine phosphatase 1b knockout and Ay mice. Hypersensitivity to leptin and obesity reduced BP response to ganglionic blockade in both strains and plasma catecholamine levels in protein tyrosine phosphatase 1b knockout mice. Hypersensitivity to leptin and obesity significantly increased plasma aldosterone levels and adrenal CYP11B2 expression. Chronic leptin receptor antagonism reduced aldosterone levels. Furthermore, chronic leptin and mineralocorticoid receptor blockade reduced BP and improved endothelial function in both leptin-sensitized and obese hyperleptinemic female mice. Together, these data demonstrate that leptin induces hypertension and endothelial dysfunction via aldosterone-dependent mechanisms in female mice and suggest that obesity leads to cardiovascular disease via sex

  14. Obesity-induced Endoplasmic Reticulum Stress Causes Lung Endothelial Dysfunction and Promotes Acute Lung Injury.

    PubMed

    Shah, Dilip; Romero, Freddy; Guo, Zhi; Sun, Jianxin; Li, Jonathan; Kallen, Caleb B; Naik, Ulhas P; Summer, Ross

    2017-03-09

    Obesity is a significant risk factor for the acute respiratory distress syndrome (ARDS). The mechanisms underlying this association are unknown. We recently showed that diet-induced obese (DIO) mice exhibit pulmonary vascular endothelial dysfunction which is associated with enhanced susceptibility to lipopolysaccharide (LPS)-induced lung injury. Here, we demonstrate that lung endothelial dysfunction in DIO mice coincides with increased endoplasmic reticulum (ER) stress. Specifically, we observed enhanced expression of the major sensors of misfolded proteins including PERK, IREα and ATF6, in whole lung and in lung endothelial cells isolated from DIO mice. Further, we found that lung endothelial cells exposed to serum from obese mice, or to saturated fatty acids that mimic obese serum, resulted in enhanced expression of markers of ER stress and the induction of other biological responses that typify the lung endothelium of DIO mice. Similar changes were observed in lung endothelial cells and in whole lung tissue after exposure to tunicamycin, a compound that causes ER stress by blocking N-linked glycosylation; indicating that ER stress causes endothelial dysfunction in the lung. Treatment with 4-PBA, a chemical protein chaperone that reduces ER stress, restored vascular endothelial cell expression of adhesion molecules and protected against LPS-induced acute lung injury in DIO mice. Our work indicates that fatty acids in obese serum induce ER stress in the pulmonary endothelium leading to pulmonary endothelial cell dysfunction. Our work suggests that reducing protein load in the endoplasmic reticulum of pulmonary endothelial cells might protect against ARDS in obese individuals.

  15. Diet-induced obesity elevates colonic TNF-alpha in mice and is accompanied by an activation of Wnt signaling: a mechanism for obesity-associated colorectal cancer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inflammation associated with obesity may play a role in colorectal carcinogenesis, but the underlying mechanism remains unclear. This study investigated whether the Wnt pathway, an intracellular signaling cascade that plays a critical role in colorectal carcinogenesis, is activated by obesity-induce...

  16. Up-regulation of heme oxygenase-1 contributes to the amelioration of aluminum-induced oxidative stress in Medicago sativa.

    PubMed

    Cui, Weiti; Zhang, Jing; Xuan, Wei; Xie, Yanjie

    2013-10-15

    In this report, pharmacological, histochemical and molecular approaches were used to investigate the effect of heme oxygenase-1 (HO-1) up-regulation on the alleviation of aluminum (Al)-induced oxidative stress in Medicago sativa. Exposure of alfalfa to AlCl3 (0-100 μM) resulted in a dose-dependent inhibition of root elongation as well as the enhancement of thiobarbituric acid reactive substances (TBARS) content. 1 and 10 μM (in particular) Al(3+) increased alfalfa HO-1 transcript or its protein level, and HO activity in comparison with the decreased changes in 100 μM Al-treated samples. After recuperation, however, TBARS levels in 1 and 10 μM Al-treated alfalfa roots returned to control values, which were accompanied with the higher levels of HO activity. Subsequently, exogenous CO, a byproduct of HO-1, could substitute for the cytoprotective effects of the up-regulation of HO-1 in alfalfa plants upon Al stress, which was confirmed by the alleviation of TBARS and Al accumulation, as well as the histochemical analysis of lipid peroxidation and loss of plasma membrane integrity. Theses results indicated that endogenous CO generated via heme degradation by HO-1 could contribute in a critical manner to its protective effects. Additionally, the pretreatments of butylated hydroxytoluene (BHT) and hemin, an inducer of HO-1, exhibited the similar cytoprotective roles in the alleviation of oxidative stress, both of which were impaired by the potent inhibitor of HO-1, zinc protoporphyrin IX (ZnPP). However, the Al-induced inhibition of root elongation was not influenced by CO, BHT and hemin, respectively. Together, the present results showed up-regulation of HO-1 expression could act as a mechanism of cell protection against oxidative stress induced by Al treatment.

  17. Diet- and genetically-induced obesity differentially affect the fecal microbiome and metabolome in Apc1638N mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is a risk factor for colorectal cancer (CRC), and alterations in the colonic microbiome and metabolome may be mechanistically involved in this relationship. The relative contribution of diet and obesity per se are unclear. We compared the effect of diet- and genetically-induced obesity on th...

  18. Ladder-Climbing Training Prevents Bone Loss and Microarchitecture Deterioration in Diet-Induced Obese Rats.

    PubMed

    Tang, Liang; Gao, Xiaohang; Yang, Xiaoying; Liu, Chentao; Wang, Xudan; Han, Yanqi; Zhao, Xinjuan; Chi, Aiping; Sun, Lijun

    2016-01-01

    Resistance exercise has been proved to be effective in improving bone quality in both animal and human studies. However, the issue about whether resistance exercise can inhibit obesity-induced bone loss has not been previously investigated. In the present study, we have evaluated the effects of ladder-climbing training, one of the resistance exercises, on bone mechanical properties and microarchitecture in high-fat (HF) diet-induced obese rats. Twenty-four rats were randomly assigned to the Control, HF + sedentary (HF-S) and HF + ladder-climbing training (HF-LCT) groups. Rats in the HF-LCT group performed ladder-climbing training for 8 weeks. The results showed that ladder-climbing training significantly reduced body and fat weight, and increased muscle mass along with a trend toward enhanced muscle strength in diet-induced obese rats. MicroCT analysis demonstrated that obesity-induced bone loss and architecture deterioration were significantly mitigated by ladder-climbing training, as evidenced by increased trabecular bone mineral density, bone volume over total volume, trabecular number and thickness, and decreased trabecular separation and structure model index. However, neither HF diet nor ladder-climbing training had an impact on femoral biomechanical properties. Moreover, ladder-climbing training significantly increased serum adiponectin, decreased serum leptin, TNF-α, IL-6 levels, and downregulated myostatin (MSTN) expression in diet-induced obese rats. Taken together, ladder-climbing training prevents bone loss and microarchitecture deterioration in diet-induced obese rats through multiple mechanisms including increasing mechanical loading on bone due to improved skeletal muscle mass and strength, regulating the levels of myokines and adipokines, and suppressing the release of pro-inflammatory cytokines. It indicates that resistance exercise may be a promising therapy for treating obesity-induced bone loss.

  19. Effects of Diet-Induced Obesity on Motivation and Pain Behavior in an Operant Assay

    PubMed Central

    Rossi, Heather L.; Luu, Anthony K.S.; Kothari, Sunny D.; Kuburas, Adisa; Neubert, John K.; Caudle, Robert M.; Recober, Ana

    2013-01-01

    Obesity has been associated with multiple chronic pain disorders, including migraine. We hypothesized that diet-induced obesity would be associated with a reduced threshold for thermal nociception in the trigeminal system. In this study, we sought to examine the effect of diet-induced obesity on facial pain behavior. Mice of two different strains were fed high-fat or regular diet and tested using a well-established operant facial pain assay. We found that the effects of diet on behavior in this assay were strain and reward dependent. Obesity prone C57BL/6J mice fed high-fat diet display lower number of licks of a caloric, palatable reward (33% sweetened condensed milk or 30% sucrose) than control mice. This occurred at all temperatures, in both sexes, and was evident even before the onset of obesity. This diminished reward-seeking behavior was not observed in obesity resistant SKH1E mice. These findings suggest that diet and strain interact to modulate reward-seeking behavior. Furthermore, we observed a difference between diet groups in operant behavior with caloric, palatable rewards, but not with a non-caloric neutral reward (water). Importantly, we found no effect of diet-induced obesity on acute thermal nociception in the absence of inflammation or injury. This indicates that thermal sensation in the face is not affected by obesity-associated peripheral neuropathy as it occurs when studying pain behaviors in the rodent hindpaw. Future studies using this model may reveal whether obesity facilitates the development of chronic pain after injury or inflammation. PMID:23333672

  20. Regulation of hypothalamic neuropeptides gene expression in diet induced obesity resistant rats: possible targets for obesity prediction?

    PubMed

    Cifani, Carlo; Micioni Di Bonaventura, Maria V; Pucci, Mariangela; Giusepponi, Maria E; Romano, Adele; Di Francesco, Andrea; Maccarrone, Mauro; D'Addario, Claudio

    2015-01-01

    Several factors play a role in obesity (i.e., behavior, environment, and genetics) and epigenetic regulation of gene expression has emerged as a potential contributor in the susceptibility and development of obesity. To investigate the individual sensitivity to weight gain/resistance, we here studied gene transcription regulation of several hypothalamic neuropeptides involved in the control of energy balance in rats developing obesity (diet-induced obesity, DIO) or not (diet resistant, DR), when fed with a high fat diet. Rats have been followed up to 21 weeks of high fat diet exposure. After 5 weeks high fat diet exposure, the obese phenotype was developed and we observed a selective down-regulation of the orexigenic neuropeptide Y (NPY) and peroxisome proliferator-activated receptor gamma (PPAR-γ) genes. No changes were observed in the expression of the agouti-related protein (AgRP), as well as for all the anorexigenic genes under study. After long-term high fat diet exposure (21 weeks), NPY and PPAR-γ, as well as most of the genes under study, resulted not be different between DIO and DR, whereas a lower expression of the anorexigenic pro-opio-melanocortin (POMC) gene was observed in DIO rats when compared to DR rats. Moreover we observed that changes in NPY and POMC mRNA were inversely correlated with gene promoters DNA methylation. Our findings suggest that selective alterations in hypothalamic peptide genes regulation could contribute to the development of overweight in rats and that environmental factor, as in this animal model, might be partially responsible of these changes via epigenetic mechanism.

  1. Cyclic stretch induces upregulation of endothelin-1 with keratinocytes in vitro: Possible role in mechanical stress-induced hyperpigmentation

    SciTech Connect

    Kurita, Masakazu; Okazaki, Mutsumi; Fujino, Takashi; Takushima, Akihiko; Harii, Kiyonori

    2011-05-27

    Highlights: {yields} Influence of cyclic stretch on melanogenetic paracrine cytokines was investigated. {yields} Keratinocyte-derived endothelin-1 was upregulated with cyclic stretch. {yields} Degree of upregulation increases dose-dependently. {yields} This upregulation possibly plays a role in the pathogenesis of pigmented disorders. -- Abstract: The aim of this study was to investigate the possible pathological relation between mechanical stress and hyperpigmentation. We did this by investigating the influence of cyclic stretch on the expression of keratinocyte- and fibroblast-derived melanogenetic paracrine cytokines in vitro. Using primary human keratinocytes and fibroblasts, alterations of mRNA expression of melanogenetic paracrine cytokines due to cyclic stretch were investigated using a real-time polymerase chain reaction (PCR). The cytokines included basic fibroblast growth factor (bFGF), stem cell factor (SCF), granulocyte/macrophage colony-stimulating factor, interleukin-1{alpha}, and endothelin-1 (ET-1) for keratinocytes and bFGF, SCF, and hepatocyte growth factor for fibroblasts. The dose dependence of keratinocyte-derived ET-1 upregulation was further investigated using real-time PCR and an enzyme-linked immunosorbent assay. We also investigated the effects of cyclic stretch on the proliferation and differentiation of keratinocytes. Among the melanogenetic paracrine cytokines investigated, keratinocyte-derived ET-1 was consistently upregulated in all four cell lines. The degree of upregulation increased with the degree of the length and frequency of the stretch; in contrast, cell number and differentiation markers showed no obvious alterations with cyclic stretch. Keratinocyte-derived ET-1 upregulation possibly plays a significant role in the pathogenesis of pigmented disorders, such as friction melanosis, caused by mechanical stress.

  2. Anti-obesity effect of Gymnema sylvestre extract on high fat diet-induced obesity in Wistar rats.

    PubMed

    Kumar, V; Bhandari, U; Tripathi, C D; Khanna, G

    2013-12-01

    Gymnema sylvestre R. BR. (Asclepiadaceae) has been used frequently in traditional Indian folk medicine for the treatment of diabetes. Study was performed in high fat diet (HFD)-induced obesity in murine model. Obesity was induced by oral feeding of HFD for 28 days. The anti obesity effect of water soluble fraction of Gymnema sylvestre extract (120 mg/kg, p.o. for 21 days) in HFD fed rats was evaluated by the measurement of body weight gain, food intake, hemodynamic changes (systolic, diastolic, mean blood pressure and heart rate), serum lipid profiles (triglycerides, total cholesterol, LDL-cholesterol, HDL-cholesterol), leptin, insulin, glucose, apolipoproteins A1 and B, lactate dehydrogenase (LDH) and antioxidant enzymes such as reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S transferase (GST), superoxide dismutase (SOD) and catalase (CAT) levels in liver tissues. Organs and visceral fat pad weight were measured. Histopathological studies were also carried out. Water soluble fraction of G. sylvestre ethanolic extract and rimonabant significantly reduced serum lipids, leptin, insulin, glucose, apolipoprotein B and LDH levels while it significantly increased the HDL-cholesterol, apolipoprotein A1 and antioxidant enzymes levels in liver tissue as compared to the HFD fed rats. Histopathological studies of tissues showed no pathological changes. The results of this study show that water soluble fraction of G. sylvestre extract possess antiobesity effect.

  3. Purple Sweet Potato Attenuate Weight Gain in High Fat Diet Induced Obese Mice.

    PubMed

    Ju, Ronghui; Zheng, Shujuan; Luo, Hongxia; Wang, Changgang; Duan, Lili; Sheng, Yao; Zhao, Changhui; Xu, Wentao; Huang, Kunlun

    2017-03-01

    Purple sweet potato (PSP) is widely grown in Asia and considered as a healthy vegetable. The objective of the current study was to determine the anti-obesity effect of the PSP on high fat diet induced obese C57BL/6J mice. The mice were administrated with high fat diet supplemented with the sweet potato (SP) or PSP at the concentration of 15% and 30% for 12 wk, respectively. The results showed that the supplementation of SP or PSP at 30% significantly ameliorated high fat diet induced obesity and its associated risk factors, including reduction of body weight and fat accumulation, improvement of lipid profile and modulation of energy expenditure. Moreover, PSP also posed beneficial effect on the liver and kidney functions. These results indicate that PSP and SP have anti-obesity effect and are effective to reduce the metabolic risk.

  4. Dietary obesity-induced Egr-1 in adipocytes facilitates energy storage via suppression of FOXC2

    PubMed Central

    Zhang, Jifeng; Zhang, Yuan; Sun, Tingwan; Guo, Fang; Huang, Shengping; Chandalia, Menisha; Abate, Nicola; Fan, Daping; Xin, Hong-Bo; Chen, Y. Eugene; Fu, Mingui

    2013-01-01

    The molecular mechanism to regulate energy balance is not completely understood. Here we observed that Egr-1 expression in white adipose tissue (WAT) was highly correlated with dietary-induced obesity and insulin resistance both in mice and humans. Egr-1 null mice were protected from diet-induced obesity and obesity-associated pathologies such as fatty liver, insulin resistance, hyperlipidemia and hyperinsulinemia. This phenotype can be largely explained by the increase of energy expenditure in Egr-1 null mice. Characterization of these mice revealed that the expression of FOXC2 and its target genes were significantly elevated in white adipose tissues, leading to WAT energy expenditure instead of energy storage. Altogether, these studies suggest an important role for Egr-1, which, by repressing FOXC2 expression, promotes energy storage in WAT and favored the development of obesity under high energy intake. PMID:23502673

  5. Histidine supplementation alleviates inflammation in the adipose tissue of high-fat diet-induced obese rats via the NF-κB- and PPARγ-involved pathways.

    PubMed

    Sun, Xiaowei; Feng, Rennan; Li, Yanchuan; Lin, Song; Zhang, Wei; Li, Ying; Sun, Changhao; Li, Songtao

    2014-08-28

    Obesity is considered to be accompanied by a chronic low-grade inflammatory state that contributes to the occurrence of many chronic diseases. Our previous study has demonstrated that histidine supplementation significantly ameliorates inflammation and oxidative stress in obese women. However, the in vivo potential mechanisms are not known. The present study was conducted to investigate the mechanisms underlying the effects of histidine on inflammation in a high-fat diet (HFD)-induced female obese rat model. An obese model was established in female Sprague-Dawley rats by HFD feeding for 8 weeks and followed by histidine supplementation for another 4 weeks. The results revealed that HFD-increased body weight and HFD-lowered serum histidine concentrations were significantly reversed by histidine supplementation (P< 0·05). In addition, the serum concentrations of TNF-α, IL-6, C-reactive protein (CRP) and malondialdehyde were significantly reduced and those of superoxide dismutase (SOD) were significantly increased by histidine supplementation when compared with those in obese rats (P< 0·05). Correspondingly, the mRNA expressions of TNF-α, IL-6 and CRP in the adipose tissue were significantly down-regulated and that of CuZnSOD was significantly up-regulated by histidine supplementation (P< 0·05). Histidine supplementation significantly reduced the HFD-induced translocation of NF-κB p65 into the nucleus (P= 0·032) by reducing the phosphorylation of the inhibitor of κBα in the adipose tissue. The results also revealed that the expression of adiponectin was markedly increased both in the serum and in the adipose tissue after histidine supplementation, accompanied by the activation of PPARγ (P= 0·021). These findings indicate that histidine is an effective candidate for ameliorating inflammation and oxidative stress in obese individuals via the NF-κB- and PPARγ-involved pathways.

  6. Reduction of obesity, as induced by leptin, reverses endothelial dysfunction in obese (Lep(ob)) mice

    NASA Technical Reports Server (NTRS)

    Winters, B.; Mo, Z.; Brooks-Asplund, E.; Kim, S.; Shoukas, A.; Li, D.; Nyhan, D.; Berkowitz, D. E.

    2000-01-01

    Obesity is a major health care problem and is associated with significant cardiovascular morbidity. Leptin, a neuroendocrine hormone released by adipose tissue, is important in modulating obesity by signaling satiety and increasing metabolism. Moreover, leptin receptors are expressed on vascular endothelial cells (ECs) and mediate angiogenesis. We hypothesized that leptin may also play an important role in vasoregulation. We investigated vasoregulatory mechanisms in the leptin-deficient obese (ob/ob) mouse model and determined the influence of leptin replacement on endothelial-dependent vasorelaxant responses. The direct effect of leptin on EC nitric oxide (NO) production was also tested by using 4, 5-diaminofluorescein-2 diacetate staining and measurement of nitrate and nitrite concentrations. Vasoconstrictor responses to phenylephrine, norepinephrine, and U-46619 were markedly enhanced in aortic rings from ob/ob mice and were modulated by NO synthase inhibition. Vasorelaxant responses to ACh were markedly attenuated in mesenteric microvessels from ob/ob mice. Leptin replacement resulted in significant weight loss and reversal of the impaired endothelial-dependent vasorelaxant responses observed in ob/ob mice. Preincubation of ECs with leptin enhanced the release of NO production. Thus leptin-deficient ob/ob mice demonstrate marked abnormalities in vasoregulation, including impaired endothelial-dependent vasodilation, which is reversed by leptin replacement. These findings may be partially explained by the direct effect of leptin on endothelial NO production. These vascular abnormalities are similar to those observed in obese, diabetic, leptin-resistant humans. The ob/ob mouse may, therefore, be an excellent new model for the study of the cardiovascular effects of obesity.

  7. Baicalein Decreases Hydrogen Peroxide-Induced Damage to NG108-15 Cells via Upregulation of Nrf2.

    PubMed

    Yeh, Chao-Hung; Ma, Kuo-Hsing; Liu, Pei-Shan; Kuo, Jung-Kuei; Chueh, Sheau-Huei

    2015-08-01

    Baicalein is a flavonoid inhibitor of 12-lipoxygenase. Here, we investigated its effect on hydrogen peroxide-induced damage to NG108-15 cells. Hydrogen peroxide activated the mitochondrial apoptotic pathway, decreased Nrf2 expression, increased reactive oxygen species (ROS) levels, reduced viability, and increased cell death after 2-24 h treatment of NG108-15 cells. Co-treatment with hydrogen peroxide and baicalein completely suppressed the activation of mitochondrial apoptotic pathway by upregulating Nrf2 expression and reducing ROS stress and partially inhibited the effects on cell viability and cell death. Silencing of 12-lipoxygenase had a similar protective effect to baicalein on hydrogen peroxide-induced damage by blocking the hydrogen peroxide-induced decrease in Nrf2 expression and increase in ROS levels. Neither protective effect was altered by addition of 12-hydroxyeicosatetraenoic acid, the product of 12-lipoxygenase, suggesting that hydrogen peroxide induced damage via 12-lipoxygenase by another, as yet unknown, mechanism, rather than activating it. Co-treatment of cells with hydrogen peroxide and N-acetylcysteine or the Nrf2 inducer sulforaphane reduced hydrogen peroxide-induced damage in a similar fashion to baicalein, while the Nrf2 inhibitor retinoic acid blocked the protective effect of baicalein. Silencing Nrf2 also inhibited the protective effects of baicalein, sulforaphane, and N-acetylcysteine and resulted in high ROS levels, suggesting ROS elimination was mediated by Nrf2. Taken together our results suggest that baicalein protects cells from hydrogen peroxide-induced activation of the mitochondrial apoptotic pathway by upregulating Nrf2 and inhibiting 12-lipoxygenase to block the increase in ROS levels. Hydrogen peroxide also activates a second mitochondrial dysfunction independent death pathway which is resistant to baicalein.

  8. Combinatorial gene construct and non-viral delivery for anti-obesity in diet-induced obese mice.

    PubMed

    Park, Hongsuk; Cho, Sungpil; Han, Yong Hwan; Janat-Amsbury, Margit M; Boudina, Sihem; Bae, You Han

    2015-06-10

    The combinatorial peptidergic therapy of islet amyloid polypeptide (IAPP) and leptin (LEP) analogues was once an optimistic option in treating obese animals and patients. However, the need for frequent administrations and its negative side effects prevent it from being a viable choice. Here, we developed a combinatorial gene therapy of IAPP and LEP, where two genes are inserted into a single plasmid with self-cleaving furin and 2A sites to treat diet-induced obese (DIO) mice. The developed plasmid DNA (pDNA) individually produced both IAPP and LEP peptides in vitro and in vivo. The pDNA was delivered with a non-viral polymeric carrier, and its once-a-week administrations demonstrated a synergistic loss of body weight and significant reductions of fat mass, blood glucose, and lipid levels in DIO mice. The results suggest that the combinatorial gene therapy would have higher potential than the peptidergic approach for future translation due to its improved practicability.

  9. Raphanus sativus cv. Sango Sprout Juice Decreases Diet-Induced Obesity in Sprague Dawley Rats and Ameliorates Related Disorders

    PubMed Central

    Sapone, Andrea; De Nicola, Gina Rosalinda; Babot Marquillas, Clara; Iori, Renato; Antonazzo, Ippazio Cosimo; Gentilini, Fabio; Paolini, Moreno

    2016-01-01

    Background Obesity is recognized as a leading global health problem, correlated with an increased risk for several chronic diseases. One strategy for weight control management includes the use of vegetables rich in bioactive compounds to counteract weight gain, improve the antioxidant status and stimulate lipid catabolism. Aim of the Study The aim of this study was to investigate the role of Raphanus sativus Sango sprout juice (SSJ), a Brassica extraordinarily rich in anthocyanins (AC) and isothiocyanates (ITCs), in a non-genetic model of obesity (high fat diet-HFD induced). Methods Control groups were fed with HFD or regular diet (RD). After a 10-week period, animals were assigned to experimental units and treated by gavage for 28 days as follows: HFD and RD control groups (rats fed HFD or RD and treated with vehicle only) and HFD-treated groups (rats fed HFD and treated with 15, 75 or 150 mg/kg b.w. of SSJ). Body weight and food consumption were recorded and serum lipid profile was measured (total cholesterol, triglycerides, and non-esterified fatty acids). Hepatic phase-I, phase-II as well as antioxidant enzymatic activities were assessed. Results SSJ lowered total cholesterol level, food intake and liver weight compared with HFD rodents. SSJ at medium dose proved effective in reducing body-weight (~19 g reduction). SSJ was effective in up-regulating the antioxidant enzymes catalase, NAD(P)H:quinone reductase, oxidised glutathione reductase and superoxide dismutase, which reached or exceeded RD levels, as well as the phase II metabolic enzyme UDP-glucuronosyl transferase (up to about 43%). HFD up-regulated almost every cytochrome P450 isoform tested, and a mild down-regulation to baseline was observed after SSJ intervention. Conclusion This work reveals, for the first time, the antioxidant, hypolipidemic and antiobesity potential of SSJ, suggesting its use as an efficient new functional food/nutraceutical product. PMID:26987061

  10. Inhibition of STAT3 signaling blocks obesity-induced mammary hyperplasia in a mouse model

    PubMed Central

    Park, Jeong Won; Zhao, Li; Willingham, Mark C; Cheng, Sheue-Yann

    2017-01-01

    Compelling epidemiologic evidence indicates that obesity is a risk factor for human cancers, including breast. However, molecular mechanisms by which obesity could contribute to the development of breast cancer remain unclear. To understand the impact of obesity on breast cancer development, we used a mutant mouse that expresses a mutated thyroid hormone receptor β (denoted as PV) with haplodeficiency of the Pten gene (ThrbPV/PVPten+/- mice). We previously showed that adult nulliparous female ThrbPV/PVPten+/- mice developed extensive mammary hyperplasia and breast tumors. In this study, we induced obesity in ThrbPV/PVPten+/- mice by feeding them a high fat diet (HFD). We found HFD exacerbated the extent of mammary hyperplasia in ThrbPV/PVPten+/- mice. HFD elevated serum leptin levels but had no effect on the levels of serum thyroid stimulating hormone, thyroid hormones, and estrogens. Molecular analysis showed that the obesity-induced hyperplasia was mediated by the leptin/leptin receptor-JAK1-STAT3 pathway to increase key cell cycle regulators to stimulate mammary epithelial cell proliferation. Activated STAT3 signaling led to altered expression in the key regulators of epithelial-mesenchymal-transition (EMT) to augment invasiveness and migration of mammary proliferating epithelial cells. Moreover, treatment of HFD-ThrbPV/PVPten+/- mice with a STAT3 inhibitor, S3I-201, markedly reversed the obesity-induced mammary hyperplasia and reduced EMT signals to lessen cell invasiveness and migration. Our studies not only elucidated how obesity could contribute to mammary hyperplasia at the molecular level, but also, importantly, demonstrated that inhibition of the STAT3 activity could be a novel treatment strategy for obesity-induced breast cancer progression.

  11. The Anti-Inflammatory Effect of Prunus yedoensis Bark Extract on Adipose Tissue in Diet-Induced Obese Mice

    PubMed Central

    Kang, Hee; Kwak, Tae-Kyung; Kim, Bo-Geun; Lee, Kyung-Jin

    2015-01-01

    Chronic, low-grade inflammatory responses occur in obese adipose tissue and play a crucial role in the development of insulin resistance. Macrophages exposed to high glucose upregulate the expression of SRA, a macrophage-specific scavenger receptor. The present study investigated whether Prunus yedoensis (PY) bark extract affects the inflammatory response and scavenger receptor gene expression observed in a diet-induced obesity model in vivo. Oral administration of PY extract significantly reduced fasting blood glucose levels without a change in body weight in mice fed a high fat diet for 17 weeks. PY extract significantly suppressed expression of inflammatory and macrophage genes such as tumor necrosis factor-α, interleukin-6, and F4/80 in epididymal adipose tissue. Among scavenger receptor genes, SRA expression was significantly reduced. The inhibitory responses of PY extract and its fractions were determined through evaluation of scavenger receptor expression in THP-1 cells. PY extract and its ethyl acetate fraction decreased the levels of SRA mRNA and phospho-ERK1/2 during monocyte differentiation. Our data indicate that the anti-inflammatory effects of PY extract and its downregulation of SRA seem to account for its hypoglycemic effects. PMID:26413130

  12. Proteomic pattern changes associated with obesity-induced asthenozoospermia.

    PubMed

    Liu, Y; Guo, Y; Song, N; Fan, Y; Li, K; Teng, X; Guo, Q; Ding, Z

    2015-03-01

    Obesity, an increasingly frequent societal disease can also be accompanied by declines in spermatozoa quality and male subfecundity. To determine if there are obesity-associated proteomic changes potentially affecting sperm quality and motility, differential proteomic analysis was performed on spermatozoa from both obesity-associated asthenozoospermia and clinically healthy individuals, using a label-free quantitative LC-MS/MS approach. We resolved 1975 proteins in the human sperm proteome, amongst which, 105 proteins were less abundant, whereas 22 other proteins increased in obesity-associated asthenozoospermia. Functional category analyses indicated that the differentially expressed proteins are mainly related to cytoskeletal regulation, vesicle biogenesis, metabolism, and protein degradation involved in spermiogenesis and sperm motility. Furthermore, declines in endoplasmic reticulum protein 57 (ERp57) and actin-binding-related protein T2 (ACTRT2) expression were verified by immunofluorescence, Western blot, and flow cytometry analyses. It is evident that ERp57 is localized in the acrosome region, neck and principal piece of human spermatozoa, whereas ACTRT2 is localized in the post-acrosomal region and middle piece. Thus, these differences in protein expression in asthenozoospermia may contribute to the underlying sperm quality defects afflicting these individuals. Notably, declines in ERp57 and ACTRT2 expression in obesity-associated asthenozoospermia may play critical roles in reducing sperm motility.

  13. 2-Chloroethanol Induced Upregulation of Matrix Metalloproteinase-2 in Primary Cultured Rat Astrocytes Via MAPK Signal Pathways

    PubMed Central

    Sun, Qi; Liao, Yingjun; Wang, Tong; Tang, Hongge; Wang, Gaoyang; Zhao, Fenghong; Jin, Yaping

    2017-01-01

    This study was to explore the mechanisms underlying 1,2-dichloroethane (1,2-DCE) induced brain edema by focusing on alteration of matrix metalloproteinase-2 (MMP-2) in rat astrocytes induced by 2-chloroethanol (2-CE), an intermediate metabolite of 1,2-DCE in vivo. Protein and mRNA levels of MMP-2, and the phosphorylated protein levels of p38 MAPK (p-p38), extracellular signal regulated protein kinase (p-ERK1/2) and c-Jun N-terminal kinase (p-JNK1/2) in astrocytes were examined by immunostaining, western blot or real-time RT-PCR analysis. Findings from this study disclosed that protein levels of MMP-2 were upregulated by 2-CE in astrocytes. Meanwhile, protein levels of p-p38, p-ERK1/2 and p-JNK1/2 were also increased apparently in the cells treated with 2-CE. Moreover, pretreatment of astrocytes with SB202190 (inhibitor of p38 MAPK), U0126 (inhibitor of ERK1/2) or SP600125 (inhibitor of JNK1/2) could suppress the upregulated expression of p-p38, p-ERK1/2, and p-JNK1/2. In response to suppressed protein levels of p-p38 and p-JNK1/2, the protein levels of MMP-2 also decreased significantly, indicating that activation of MAPK signal pathways were involved in the mechanisms underlying 2-CE-induced upregulation of MMP-2 expression. PMID:28101000

  14. Diet-induced obesity causes long QT and reduces transcription of voltage-gated potassium channels.

    PubMed

    Huang, Haiyan; Amin, Vaibhav; Gurin, Michael; Wan, Elaine; Thorp, Edward; Homma, Shunichi; Morrow, John P

    2013-06-01

    In humans, obesity is associated with long QT, increased frequency of premature ventricular complexes, and sudden cardiac death. The mechanisms of the pro-arrhythmic electrophysiologic remodeling of obesity are poorly understood. We tested the hypothesis that there is decreased expression of voltage-gated potassium channels in the obese heart, leading to long QT. Using implanted telemeters, we found that diet-induced obese (DIO) wild-type mice have impaired cardiac repolarization, demonstrated by long QT, as well as more frequent ventricular ectopy, similar to obese humans. DIO mice have reduced protein and mRNA levels of the potassium channel Kv1.5 caused by a reduction of the transcription factor cyclic AMP response element binding protein (CREB) in DIO hearts. We found that CREB knock-down by siRNA reduces Kv1.5, CREB binds to the Kv1.5 promoter in the heart, and CREB increases transcription of mouse and human Kv1.5 promoters. The reduction in CREB protein during lipotoxicity can be rescued by inhibiting protein kinase D (PKD). Our results identify a mechanism for obesity-induced electrophysiologic remodeling in the heart, namely PKD-induced reduction of CREB, which in turn decreases expression of the potassium channel Kv1.5.

  15. The NLRP3 inflammasome instigates obesity-induced inflammation and insulin resistance.

    PubMed

    Vandanmagsar, Bolormaa; Youm, Yun-Hee; Ravussin, Anthony; Galgani, Jose E; Stadler, Krisztian; Mynatt, Randall L; Ravussin, Eric; Stephens, Jacqueline M; Dixit, Vishwa Deep

    2011-02-01

    The emergence of chronic inflammation during obesity in the absence of overt infection or well-defined autoimmune processes is a puzzling phenomenon. The Nod-like receptor (NLR) family of innate immune cell sensors, such as the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (Nlrp3, but also known as Nalp3 or cryopyrin) inflammasome are implicated in recognizing certain nonmicrobial originated 'danger signals' leading to caspase-1 activation and subsequent interleukin-1β (IL-1β) and IL-18 secretion. We show that calorie restriction and exercise-mediated weight loss in obese individuals with type 2 diabetes is associated with a reduction in adipose tissue expression of Nlrp3 as well as with decreased inflammation and improved insulin sensitivity. We further found that the Nlrp3 inflammasome senses lipotoxicity-associated increases in intracellular ceramide to induce caspase-1 cleavage in macrophages and adipose tissue. Ablation of Nlrp3 in mice prevents obesity-induced inflammasome activation in fat depots and liver as well as enhances insulin signaling. Furthermore, elimination of Nlrp3 in obese mice reduces IL-18 and adipose tissue interferon-γ (IFN-γ) expression, increases naive T cell numbers and reduces effector T cell numbers in adipose tissue. Collectively, these data establish that the Nlrp3 inflammasome senses obesity-associated danger signals and contributes to obesity-induced inflammation and insulin resistance.

  16. Up-regulation of heme oxygenase-1 by isoflurane preconditioning during tolerance against neuronal injury induced by oxygen glucose deprivation.

    PubMed

    Li, Qifang; Zhu, Yesen; Jiang, Hong; Xu, Hui; Liu, Heping

    2008-09-01

    Heme oxygenase (HO) is the rate-limiting enzyme in the degradation of heme to produce bile pigments and carbon monoxide. The HO-1 isozyme is induced by a variety of factors such as heat, heme, ischemia, and hydrogen peroxide. In recent years, mounting findings have suggested that HO-1 has a neuroprotective activity against ischemic injury. The neuroprotective role of isoflurane, a commonly used anesthetic, has been well documented, but little is known about the underlying mechanisms involved. Recently, isoflurane has been shown to up-regulate HO-1 in the liver. In this study, we show that isoflurane preconditioning promotes the survival of cultured ischemic hippocampal neurons by increasing the number of surviving neurons and their viability. Further study by reverse transcription-polymerase chain reaction and Western blot analysis showed that isoflurane preconditioning significantly increases HO-1 expression in oxygen glucose deprivation (OGD)-induced neuronal injury. Furthermore, inhibition of HO activity by tin protoporphyrin partially abolishes isoflurane preconditioning's protective effect as measured by lactate dehydrogenase release in OGD neurons. These findings indicated that the neuroprotective role of isoflurane preconditioning against OGD-induced injury might be associated with its role in up-regulating HO-1 in ischemic neurons.

  17. IL-17 induces reactive astrocytes and up-regulation of vascular endothelial growth factor (VEGF) through JAK/STAT signaling

    PubMed Central

    You, Tao; Bi, Yihui; li, Jun; Zhang, Mingkai; Chen, Xuezhou; Zhang, Keke; Li, Jun

    2017-01-01

    Spinal cord injury is a grave neurological disability resulting in neuron degeneration and permanent paralysis. The inflammation triggered by the injury would promote the spinal cord lesion in turn. Activated astrocytes during inflammatory response could promote glial scar formation and contribute to the progression of the spinal cord injury. Interleukin 17 (IL-17) was upregulated in inflammatory responses to contusion or compression of the spinal cord. in this study, IL-17 could induce reactive astrocytes which was indicated by a well-known hallmark glial fibrillary acidic protein (GFAP) in vitro and in vivo. Moreover, we demonstrated that the upregulation of VEGF was induced by IL-17 human astrocytoma cells. In our further investigation, IL-17 induced the expression of VEGF in spinal cord injury by activating JAK/STAT signaling pathway both in vitro and in vivo. In addition, we also found that IL-17 significantly changed tissue preservation and residual urine volumes and blood-spinal cord-barrier integrity in vivo. This newly found IL-17-JAK/STAT-VEGF axis improves our understanding of the molecular mechanism of spinal cord injury during inflammatory response and provides another potential target of spinal cord injury. PMID:28281545

  18. Central nervous system dysfunction in obesity-induced hypertension.

    PubMed

    Head, Geoffrey A; Lim, Kyungjoon; Barzel, Benjamin; Burke, Sandra L; Davern, Pamela J

    2014-09-01

    The activation of the sympathetic nervous system is a major mechanism underlying both human and experimental models of obesity-related hypertension. While insulin and the adipokine leptin have long been thought to contribute to obesity-related neurogenic mechanisms, the evidence is now very strong that they play a major role, shown particularly in animal studies using selective receptor antagonists. There is not just maintenance of leptin's sympatho-excitatory actions as previously suggested but considerable amplification particularly in renal sympathetic nervous activity. Importantly, these changes are not dependent on short-term elevation or reduction in plasma leptin or insulin, but require some weeks to develop indicating a slow "neural adaptivity" within hypothalamic signalling. These effects can be carried across generations even when offspring are raised on a normal diet. A better understanding of the underlying mechanism should be a high research priority given the prevalence of obesity not just in the current population but also for future generations.

  19. Cancer upregulated gene 2 induces epithelial-mesenchymal transition of human lung cancer cells via TGF-β signaling.

    PubMed

    Kaowinn, Sirichat; Kim, Jeonghyo; Lee, Jaebeom; Shin, Dong Hoon; Kang, Chi-Dug; Kim, Dae-Kee; Lee, Soojin; Kang, Min Kyung; Koh, Sang Seok; Kim, Seong-Jin; Chung, Young-Hwa

    2017-01-17

    Cancer upregulated gene 2 (CUG2) enhances cell migration and invasion, but the underlying mechanism has not been revealed. Herein, CUG2 decreased the expression of E-cadherin and increased the expression of N-cadherin and vimentin, characteristics of the epithelial-mesenchymal transition (EMT). A CUG2 deletion mutant, lacking interaction with nucleophosmin 1 (NPM1), or suppression of NPM1 reduced wound healing and cell invasion, indicating that CUG2-mediated EMT requires NPM1. CUG2 enhanced activation of Smad2/3 and expression of Snail and Twist, while the CUG2 silence decreased these TGF-β signaling pathways, leading to suppression of EMT. NPM silence also inhibited the CUG2-induced TGF-β signaling. These results suggest that TGF-β signaling is involved in CUG2-induced EMT. Treatment with EW-7197, a novel inhibitor of TGF-β signaling, diminished CUG2-mediated EMT and inhibition of Akt, ERK, JNK, and p38 MAPK, non-canonical TGF-β signaling molecules, also decreased expression of Smad2/3, Snail and Twist, leading to inhibition of EMT. The results confirm that TGF-β signaling is essential for CUG2-mediated EMT. Interestingly, TGF-β enhanced CUG2 expression. We further found that both CUG2-induced TGF-β production and TGF-β-induced CUG2 up-regulation required a physical interaction between Sp1 and Smad2/3 in the CUG2 and TGF-β promoter, as demonstrated by a promoter reporter assay, immunoprecipitation, and ChIP assay. These results indicated close crosstalk between CUG2 and TGF-β. Conversely, suppression of CUG2 or NPM1 did not completely inhibit TGF-β-induced EMT, indicating that the effect of TGF-β on EMT is dominant over the effect of CUG2 on EMT. Collectively, our findings suggest that CUG2 induces the EMT via TGF-β signaling.

  20. Screening of upregulated genes induced by high density in the vetch aphid Megoura crassicauda.

    PubMed

    Ishikawa, Asano; Ishikawa, Yuki; Okada, Yasukazu; Miyazaki, Satoshi; Miyakawa, Hitoshi; Koshikawa, Shigeyuki; Brisson, Jennifer A; Miura, Toru

    2012-03-01

    Aphids exhibit several polyphenisms in which discontinuous, alternative phenotypes are produced depending on environmental conditions. One representative example is the wing polyphenism, where winged and wingless females are produced through parthenogenesis. Previous work has shown that, in some aphid species, the density condition sensed by the mother aphid determines the developmental fate of embryos in her ovary, with high densities leading to winged progeny and low densities to wingless progeny. However, little is known about the molecular and physiological mechanisms underlying the wing polyphenism. To identify genes involved in the wing-morph determination in the vetch aphid, Megoura crassicauda, we compared maternal and embryonic transcripts between high- and low-density conditions using differential display, followed by quantitative real-time PCR (qRT-PCR). Under the high-density condition, two genes (Uba1 and Naca) were found to be upregulated in maternal tissues without ovaries, while one gene (ClpP) was upregulated in ovaries containing embryos. Uba1 and Naca encode factors that function in protein modification or transcriptional/translational regulation, respectively. In addition to differential display, candidate gene approaches focusing on morphogenetic and endocrine genes, i.e., wg, dpp, ap, hh, InR, IRS, Foxo, EcR, and USP, were also carried out. We found that wg was upregulated in maternal tissues under the high-density condition. The identified genes from both approaches are candidates for further study of their involvement in the transduction of density signals in mother aphids and/or the initial process of wing differentiation in embryos.

  1. Leptin modulates the late fever response to LPS in diet-induced obese animals.

    PubMed

    Pohl, Joanna; Woodside, Barbara; Luheshi, Giamal N

    2014-11-01

    Leptin is an important modulator of both inflammation and energy homeostasis, making it a key interface between the inflammatory response to pathogenic stimuli and the energy status of the host. In previous studies we demonstrated that sickness responses to systemic immune challenge, including fever, are significantly exacerbated in diet induced obese animals. To investigate whether this exacerbation is functionally linked to the obesity associated increase in circulating levels of leptin, a species-specific leptin antiserum (LAS) was used to neutralize endogenous leptin in diet-induced obese adult male Wistar rats treated with a single intraperitoneal (i.p.) injection of lipopolysaccharide (LPS) (100μg/kg). LAS significantly reduced the magnitude of the later phases of the fever response, and attenuated the circulating levels of IL-6, IL-1ra and bioactivity of leptin in the obese animals. In addition, the antiserum significantly attenuated the hypothalamic expression of IL-1ß, IκBα, COX2, SOCS3 and IL-6 in both lean and obese rats 10h after the LPS injection and NF-IL6 in the hypothalamus of obese rats only. The relatively late rise in brain IL-6 suggested a role in mediating the extended fever response in obese animals and we tested this by neutralizing brain IL-6 using an IL6-AS injected intracerebroventricularly (4μl, icv). The IL6-AS significantly but transiently (between 9h and 12h post LPS) reduced the late fever response of obese rats. These results demonstrate that leptin plays an important part in modulating the late portion of the fever response to LPS, likely through the induction of hypothalamic IL-6 in obese animals.

  2. Inhibition of hypoxia-inducible factor via upregulation of von Hippel-Lindau protein induces “angiogenic switch off” in a hepatoma mouse model

    PubMed Central

    Iwamoto, Hideki; Nakamura, Toru; Koga, Hironori; Izaguirre-Carbonell, Jesus; Kamisuki, Shinji; Sugawara, Fumio; Abe, Mitsuhiko; Iwabata, Kazuki; Ikezono, Yu; Sakaue, Takahiko; Masuda, Atsutaka; Yano, Hirohisa; Ohta, Keisuke; Nakano, Masahito; Shimose, Shigeo; Shirono, Tomotake; Torimura, Takuji

    2015-01-01

    “Angiogenic switch off” is one of the ideal therapeutic concepts in the treatment of cancer. However, the specific molecules which can induce “angiogenic switch off” in tumor have not been identified yet. In this study, we focused on von Hippel-Lindau protein (pVHL) in hepatocellular carcinoma (HCC) and investigated the effects of sulfoquinovosyl-acylpropanediol (SQAP), a novel synthetic sulfoglycolipid, for HCC. We examined mutation ratio of VHL gene in HCC using 30 HCC samples and we treated the HCC-implanted mice with SQAP. Thirty clinical samples showed no VHL genetic mutation in HCC. SQAP significantly inhibited tumor growth by inhibiting angiogenesis in a hepatoma mouse model. SQAP induced tumor “angiogenic switch off” by decreasing hypoxia-inducible factor (HIF)-1, 2α protein via pVHL upregulation. pVHL upregulation decreased HIFα protein levels through different multiple mechanisms: (i) increasing pVHL-dependent HIFα protein degradation; (ii) decreasing HIFα synthesis with decrease of NF-κB expression; and (iii) decrease of tumor hypoxia by vascular normalization. We confirmed these antitumor effects of SQAP by the loss-of-function experiments. We found that SQAP directly bound to and inhibited transglutaminase 2. This study provides evidence that upregulation of tumor pVHL is a promising target, which can induce “angiogenic switch off” in HCC. PMID:27119112

  3. TCS2 Increases Olaquindox-Induced Apoptosis by Upregulation of ROS Production and Downregulation of Autophagy in HEK293 Cells.

    PubMed

    Li, Daowen; Zhao, Kena; Yang, Xiayun; Xiao, Xilong; Tang, Shusheng

    2017-04-07

    Olaquindox, a feed additive, has drawn public attention due to its potential mutagenicity, genotoxicity, hepatoxicity and nephrotoxicity. The purpose of this study was to investigate the role of tuberous sclerosis complex (TSC2) pathways in olaquindox-induced autophagy in human embryonic kidney 293 (HEK293) cells. The results revealed that olaquindox treatment reduced the cell viability of HEK293 cells and downregulated the expression of TSC2 in a dose- and time-dependent manner. Meanwhile, olaquindox treatment markedly induced the production of reactive oxygen species (ROS), cascaded to autophagy, oxidative stress, and apoptotic cell death, which was effectively eliminated by the antioxidant N-acetylcysteine (NAC). Furthermore, overexpression of TSC2 attenuated olaquindox-induced autophagy in contrast to inducing the production of ROS, oxidative stress and apoptosis. Consistently, knockdown of TSC2 upregulated autophagy, and decreased olaquindox-induced cell apoptosis. In conclusion, our findings indicate that TSC2 partly participates in olaquindox-induced autophagy, oxidative stress and apoptosis, and demonstrate that TSC2 has a negative regulation role in olaquindox-induced autophagy in HEK293 cells.

  4. Mitochondria-related miR-141-3p contributes to mitochondrial dysfunction in HFD-induced obesity by inhibiting PTEN

    PubMed Central

    Ji, Juan; Qin, Yufeng; Ren, Jing; Lu, Chuncheng; Wang, Rong; Dai, Xiuliang; Zhou, Ran; Huang, Zhenyao; Xu, Miaofei; Chen, Minjian; Wu, Wei; Song, Ling; Shen, Hongbing; Hu, Zhibin; Miao, Dengshun; Xia, Yankai; Wang, Xinru

    2015-01-01

    Mitochondria-related microRNAs (miRNAs) have recently emerged as key regulators of cell metabolism and can modulate mitochondrial fusion and division. In order to investigate the roles of mitochondria-related miRNAs played in obesity, we conducted comprehensive molecular analysis in vitro and in vivo. Based on high-fat-diet (HFD) induced obese mice, we found that hepatic mitochondrial function was markedly altered. Subsequently, we evaluated the expression levels of selected mitochondria-related miRNAs and found that miR-141-3p was up-regulated strikingly in HFD mice. To further verify the role of miR-141-3p in obesity, we carried out gain-and-loss-of-function study in human HepG2 cells. We found that miR-141-3p could modulate ATP production and induce oxidative stress. Through luciferase report gene assay, we identified that phosphatase and tensin homolog (PTEN) was a target of miR-141-3p. Inhibiting PTEN could alter the mitochondrial function, too. Our study suggested that mitochondria-related miR-141-3p induced mitochondrial dysfunction by inhibiting PTEN. PMID:26548909

  5. Mitochondria-related miR-141-3p contributes to mitochondrial dysfunction in HFD-induced obesity by inhibiting PTEN.

    PubMed

    Ji, Juan; Qin, Yufeng; Ren, Jing; Lu, Chuncheng; Wang, Rong; Dai, Xiuliang; Zhou, Ran; Huang, Zhenyao; Xu, Miaofei; Chen, Minjian; Wu, Wei; Song, Ling; Shen, Hongbing; Hu, Zhibin; Miao, Dengshun; Xia, Yankai; Wang, Xinru

    2015-11-09

    Mitochondria-related microRNAs (miRNAs) have recently emerged as key regulators of cell metabolism and can modulate mitochondrial fusion and division. In order to investigate the roles of mitochondria-related miRNAs played in obesity, we conducted comprehensive molecular analysis in vitro and in vivo. Based on high-fat-diet (HFD) induced obese mice, we found that hepatic mitochondrial function was markedly altered. Subsequently, we evaluated the expression levels of selected mitochondria-related miRNAs and found that miR-141-3p was up-regulated strikingly in HFD mice. To further verify the role of miR-141-3p in obesity, we carried out gain-and-loss-of-function study in human HepG2 cells. We found that miR-141-3p could modulate ATP production and induce oxidative stress. Through luciferase report gene assay, we identified that phosphatase and tensin homolog (PTEN) was a target of miR-141-3p. Inhibiting PTEN could alter the mitochondrial function, too. Our study suggested that mitochondria-related miR-141-3p induced mitochondrial dysfunction by inhibiting PTEN.

  6. Upregulation of mitochondrial protease HtrA2/Omi contributes to manganese-induced neuronal apoptosis in rat brain striatum.

    PubMed

    Jiang, J K; Ma, X; Wu, Q Y; Qian, W B; Wang, N; Shi, S S; Han, J L; Zhao, J Y; Jiang, S Y; Wan, C H

    2014-05-30

    Manganese (Mn) is an essential trace element that is required for normal brain functioning. However, excessive intake of Mn has been known to lead to neuronal loss and clinical symptoms resembling idiopathic Parkinson's disease (IPD), whose precise molecular mechanism remains largely elusive. In the study, we established a Mn-exposed rat model and identified a mitochondrial protease, the mature form of high temperature requirement A2 (HtrA2/Omi), which was significantly upregulated in rat brain striatum after Mn exposure. Western blot and immunohistochemical analyses revealed that the expression of mature HtrA2 was remarkably increased following Mn exposure. In addition, immunofluorescence assay demonstrated that overexposure to Mn could lead to significant elevation in the number of HtrA2-positive neurons. Accordingly, the expression of X-linked inhibitor of apoptosis protein (XIAP), a well-characterized target of HtrA2-mediated proteolysis, was progressively decreased following Mn exposure, and was correlated with increased level of active caspase-3. Further, we showed that Mn exposure decreased the viability and induced apparent apoptosis of NFG-differentiated PC12 cells. Importantly, the expression of HtrA2 was progressively increased, whereas the level of cellular XIAP was reduced during Mn-induced apoptosis. In addition, blockage of HtrA2 activity with UCF-101 restored Mn-induced reduction in XIAP expression. Finally, we observed that UCF-101 treatment ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings suggested that upregulated HtrA2 played a role in Mn-induced neuronal death in brain striatum.

  7. Nicotine-induced up-regulation and desensitization of alpha4beta2 neuronal nicotinic receptors depend on subunit ratio.

    PubMed

    López-Hernández, Gretchen Y; Sánchez-Padilla, Javier; Ortiz-Acevedo, Alejandro; Lizardi-Ortiz, José; Salas-Vincenty, Janice; Rojas, Legier V; Lasalde-Dominicci, José A

    2004-09-03

    Desensitization induced by chronic nicotine exposure has been hypothesized to trigger the up-regulation of the alpha4beta2 neuronal nicotinic acetylcholine receptor (nAChR) in the central nervous system. We studied the effect of acute and chronic nicotine exposure on the desensitization and up-regulation of different alpha4beta2 subunit ratios (1alpha:4beta, 2alpha:3beta, and 4alpha:1beta) expressed in Xenopus oocytes. The presence of alpha4 subunit in the oocyte plasmatic membrane increased linearly with the amount of alpha4 mRNA injected. nAChR function and expression were assessed during acute and after chronic nicotine exposure using a two-electrode voltage clamp and whole-mount immunofluorescence assay along with confocal imaging for the detection of the alpha4 subunit. The 2alpha4:3beta2 subunit ratio displayed the highest ACh sensitivity. Nicotine dose-response curves for the 1alpha4:4beta2 and 2alpha4:3beta2 subunit ratios displayed a biphasic behavior at concentrations ranging from 0.1 to 300 microm. A biphasic curve for 4alpha4:1beta2 was obtained at nicotine concentrations higher than 300 microm. The 1alpha4:4beta2 subunit ratio exhibited the lowest ACh- and nicotine-induced macroscopic current, whereas 4alpha4:1beta2 presented the largest currents at all agonist concentrations tested. Desensitization by acute nicotine exposure was more evident as the ratio of beta2:alpha4 subunits increased. All three alpha4beta2 subunit ratios displayed a reduced state of activation after chronic nicotine exposure. Chronic nicotine-induced up-regulation was obvious only for the 2alpha4: 3beta2 subunit ratio. Our data suggest that the subunit ratio of alpha4beta2 determines the functional state of activation, desensitization, and up-regulation of this neuronal nAChR. We propose that independent structural sites regulate alpha4beta2 receptor activation and desensitization.

  8. Codonopsis lanceolata Extract Prevents Diet-Induced Obesity in C57BL/6 Mice

    PubMed Central

    Lee, Jong Seok; Kim, Kui-Jin; Kim, Young-Hyun; Kim, Dan-Bi; Shin, Gi-Hae; Cho, Ju-Hyun; Kim, Bong Kyun; Lee, Boo-Yong; Lee, Ok-Hwan

    2014-01-01

    Codonopsis lanceolata extract (CLE) has been used in traditional medicine in the Asian-Pacific region for the treatment of bronchitis, cough, and inflammation. However, it is still unclear whether obesity in mice can be altered by diet supplementation with CLE. To investigate whether CLE could have preventative effects on high fat diet (HFD)-induced obesity, male C57BL/6 mice were placed on either a normal chow diet, 60% HFD, or a HFD supplemented with CLE (60, 180, and 360 mg/kg/day) for 12 weeks. CLE decreased body weight and subcutaneous and visceral fat weights in HFD-induced obese mice. CLE group mice showed lower fat accumulation and a smaller adipocyte area in the adipose tissue compared with the HFD group mice. CLE group mice exhibited lower serum levels of triglycerides, total cholesterol, low density lipoprotein (LDL), glucose, and insulin compared with the HFD group mice. In addition, CLE decreased liver weight and lowered the increase in aspartate aminotransferase (AST) and alanine transaminase (ALT) levels in HFD-induced obese mice. These results indicate that CLE can inhibit the development of diet-induced obesity and hyperlipidemia in C57BL/6 mice. PMID:25353662

  9. Nootkatone, a characteristic constituent of grapefruit, stimulates energy metabolism and prevents diet-induced obesity by activating AMPK.

    PubMed

    Murase, Takatoshi; Misawa, Koichi; Haramizu, Satoshi; Minegishi, Yoshihiko; Hase, Tadashi

    2010-08-01

    AMP-activated protein kinase (AMPK) is a serine/threonine kinase that is implicated in the control of energy metabolism and is considered to be a molecular target for the suppression of obesity and the treatment of metabolic syndrome. Here, we identified and characterized nootkatone, a constituent of grapefruit, as a naturally occurring AMPK activator. Nootkatone induced an increase in AMPKalpha1 and -alpha2 activity along with an increase in the AMP/ATP ratio and an increase the phosphorylation of AMPKalpha and the downstream target acetyl-CoA carboxylase (ACC), in C(2)C(12) cells. Nootkatone-induced activation of AMPK was possibly mediated both by LKB1 and Ca(2+)/calmodulin-dependent protein kinase kinase. Nootkatone also upregulated PPARgamma coactivator-1alpha in C(2)C(12) cells and C57BL/6J mouse muscle. In addition, administration of nootkatone (200 mg/kg body wt) significantly enhanced AMPK activity, accompanied by LKB1, AMPK, and ACC phosphorylation in the liver and muscle of mice. Whole body energy expenditure evaluated by indirect calorimetry was also increased by nootkatone administration. Long-term intake of diets containing 0.1% to 0.3% (wt/wt) nootkatone significantly reduced high-fat and high-sucrose diet-induced body weight gain, abdominal fat accumulation, and the development of hyperglycemia, hyperinsulinemia, and hyperleptinemia in C57BL/6J mice. Furthermore, endurance capacity, evaluated as swimming time to exhaustion in BALB/c mice, was 21% longer in mice fed 0.2% nootkatone than in control mice. These findings indicate that long-term intake of nootkatone is beneficial toward preventing obesity and improving physical performance and that these effects are due, at least in part, to enhanced energy metabolism through AMPK activation in skeletal muscle and liver.

  10. ALOX5AP Overexpression in Adipose Tissue Leads to LXA4 Production and Protection Against Diet-Induced Obesity and Insulin Resistance.

    PubMed

    Elias, Ivet; Ferré, Tura; Vilà, Laia; Muñoz, Sergio; Casellas, Alba; Garcia, Miquel; Molas, Maria; Agudo, Judith; Roca, Carles; Ruberte, Jesús; Bosch, Fatima; Franckhauser, Sylvie

    2016-08-01

    Eicosanoids, such as leukotriene B4 (LTB4) and lipoxin A4 (LXA4), may play a key role during obesity. While LTB4 is involved in adipose tissue inflammation and insulin resistance, LXA4 may exert anti-inflammatory effects and alleviate hepatic steatosis. Both lipid mediators derive from the same pathway, in which arachidonate 5-lipoxygenase (ALOX5) and its partner, arachidonate 5-lipoxygenase-activating protein (ALOX5AP), are involved. ALOX5 and ALOX5AP expression is increased in humans and rodents with obesity and insulin resistance. We found that transgenic mice overexpressing ALOX5AP in adipose tissue had higher LXA4 rather than higher LTB4 levels, were leaner, and showed increased energy expenditure, partly due to browning of white adipose tissue (WAT). Upregulation of hepatic LXR and Cyp7a1 led to higher bile acid synthesis, which may have contributed to increased thermogenesis. In addition, transgenic mice were protected against diet-induced obesity, insulin resistance, and inflammation. Finally, treatment of C57BL/6J mice with LXA4, which showed browning of WAT, strongly suggests that LXA4 is responsible for the transgenic mice phenotype. Thus, our data support that LXA4 may hold great potential for the future development of therapeutic strategies for obesity and related diseases.

  11. Diet-induced obesity suppresses ghrelin in rat gastrointestinal tract and serum.

    PubMed

    Sahin, Ibrahim; Aydin, Suleyman; Ozkan, Yusuf; Dagli, Adile Ferda; Akin, Kadir Okhan; Guzel, Saadet Pilten; Catak, Zekiye; Ozercan, Mehmet Resat

    2011-09-01

    The aims of the present study were to examine ghrelin expression in serum and gastrointestinal tract (GIT) tissues, and to measure tissue ghrelin levels and obesity-related alterations in some serum biochemical variables in rats with diet-induced obesity (DIO). The study included 12 male rats, 60 days old. The rats were randomly allocated to two groups (n = 6). Rats in the DIO group were fed a cafeteria-style diet to induce obesity, while those in the control group were fed on standard rat pellets. After a 12 week diet program including an adaptation period all rats were decapitated, tissues were individually fixed, ghrelin expression was examined by immunohistochemistry , and tissue and serum ghrelin levels were measured by radioimmunoassay. Serum biochemical variables were measured using an autoanalyzer. When the baseline and week 12 body mass index and GIT ghrelin expression were compared between DIO and control rats, BMI had increased and ghrelin expression decreased due to obesity. The RIA results were consistent with these findings. Serum glucose, LDL cholesterol, and total cholesterol levels were elevated and HDL cholesterol significantly decreased in the DIO group. A comparison of GIT tissues between the control and obese groups demonstrated that ghrelin was decreased in all tissues of the latter. This decrease was brought about a decline in the circulating ghrelin pool. This suggests that rather than being associated with a change in a single tissue, obesity is a pathological condition in which ghrelin expression is changed in all tissues.

  12. Up-regulated A20 promotes proliferation, regulates cell cycle progression and induces chemotherapy resistance of acute lymphoblastic leukemia cells.

    PubMed

    Chen, Shuying; Xing, Haiyan; Li, Shouyun; Yu, Jing; Li, Huan; Liu, Shuang; Tian, Zheng; Tang, Kejing; Rao, Qing; Wang, Min; Wang, Jianxiang

    2015-09-01

    A20, also known as tumor necrosis factor-α (TNFα)-induced protein 3 (TNFAIP3), has been identified as a key regulator of cell survival in many solid tumors. However, little is known about the protein expression level and function of A20 in acute lymphoblastic leukemia (ALL). In this study, we found that A20 is up-regulated in ALL patients and several cell lines. Knockdown of A20 in Jurkat, Nalm-6, and Reh cells resulted in reduced cell proliferation, which was associated with cell cycle arrest. Phospho-ERK (p-ERK) was also down-regulated, while p53 and p21 were up-regulated in A20 knockdown cells. In addition, A20 knockdown induced apoptosis in Jurkat and Reh cells and enhanced the sensitivity of these cell lines to chemotherapeutic drugs. These results indicate that A20 may stimulate cell proliferation by regulating cell cycle progression. A20 inhibited apoptosis in some types of ALL cells, thereby enhancing their resistance to chemotherapy. This effect was abolished through A20 silencing. These findings suggest that A20 may contribute to the pathogenesis of ALL and that it may be used as a new therapeutic target for ALL treatment.

  13. Xiao Yao San against Corticosterone-Induced Stress Injury via Upregulating Glucocorticoid Receptor Reaction Element Transcriptional Activity

    PubMed Central

    Cao, Guoping; Gong, Shenglan; Zhang, Fengxue

    2016-01-01

    Previous studies have revealed that uncontrollable stress can impair the synaptic plasticity and firing property of hippocampal neurons, which influenced various hippocampal-dependent tasks including memory, cognition, behavior, and mood. In this work, we had investigated the effects and mechanisms of the Chinese herbal medicine Xiao Yao San (XYS) against corticosterone-induced stress injury in primary hippocampal neurons (PHN) cells. We found that XYS and RU38486 could increase cell viabilities and decrease cell apoptosis by MTT, immunofluorescence, and flow cytometry assays. In addition, we observed that XYS notably inhibited the nuclear translocation of GR and upregulated the mRNA and protein expressions levels of Caveolin-1, GR, BDNF, TrkB, and FKBP4. However, XYS downregulated the FKBP51 expressions. Furthermore, the results of the electrophoretic mobility shift assay (EMSA) and double luciferase reporter gene detection indicated that FKBP4 promotes the transcriptional activity of GR reaction element (GRE) by binding with GR, and FKBP51 processed the opposite action. The in vivo experiment also proved the functions of XYS. These results suggested that XYS showed an efficient neuroprotection against corticosterone-induced stress injury in PHN cells by upregulating GRE transcriptional activity, which should be developed as a potential candidate for treating stress injury in the future. PMID:27822288

  14. P-selectin upregulation in bleomycin induced lung injury in rats: effect of N-acetyl-L-cysteine

    PubMed Central

    Serrano-Mollar, A; Closa, D; Cortijo, J; Morcillo, E; Prats, N; Gironella, M; Panes, J; Rosello-Catafau, J; Bulbena, O

    2002-01-01

    Background: A number of adhesion molecules are involved in the process of neutrophil infiltration into the lung. P-selectin is one of these neutrophil-endothelial cell adhesion molecules. A study was undertaken to examine the involvement of P-selectin in the development of bleomycin induced inflammation and the ability of N-acetyl-L-cysteine to reduce the potential expression of this selectin in rats. Methods: N-acetyl-L-cysteine (3 mmol/kg po) was administered daily for seven days prior to bleomycin administration (2.5 U/kg). The kinetics of P-selectin expression and the effect of N-acetyl-L-cysteine after bleomycin treatment were measured using radiolabelled antibodies. P-selectin localisation was evaluated by immunohistochemistry and neutrophil infiltration was assessed by myeloperoxidase activity. Results: Bleomycin administration resulted in an upregulation of P-selectin at 1 hour, returning to baseline at 3 hours. Myeloperoxidase activity showed a significant increase at 6 hours after bleomycin administration that lasted for 3 days. N-acetyl-L-cysteine treatment completely prevented these increases. Conclusion: Upregulation of P-selectin in the lung is associated with neutrophil recruitment in response to bleomycin. The beneficial effect of N-acetyl-L-cysteine on bleomycin induced lung injury may be explained in part by the prevention of neutrophil recruitment in the inflammatory stage of the disease. PMID:12096208

  15. Upregulation of MKP-7 in response to rosiglitazone treatment ameliorates lipopolysaccharide-induced destabilization of SIRT1 by inactivating JNK.

    PubMed

    Hwang, Jung Seok; Ham, Sun Ah; Yoo, Taesik; Lee, Won Jin; Paek, Kyung Shin; Kim, Jae-Hwan; Lee, Chi-Ho; Seo, Han Geuk

    2016-12-01

    Silent mating type information regulation 2 homolog 1 (SIRT1), a NAD-dependent deacetylase, mediates cellular processes involved in gene silencing and aging. The regulation of lifespan by SIRT1 has been extensively investigated, but less is known about the mechanisms associated with its cellular turnover during inflammatory responses. In this study, we found that peroxisome proliferator-activated receptor (PPAR) γ is associated with SIRT1 stability in murine macrophage RAW 264.7 cells exposed to lipopolysaccharide (LPS). Activation of PPARγ by rosiglitazone, a specific ligand of PPARγ, rescues LPS-induced destabilization of SIRT1, with a concomitant decrease in phosphorylation of residue Ser-46, which is targeted by JNK-1 to promote proteasome-mediated degradation of SIRT1. The rosiglitazone-mediated increase in SIRT1 stability is accompanied by upregulation of mitogen-activated protein kinase phosphatase (MKP)-7, a JNK-specific phosphatase. These effects are significantly influenced by ablation or ectopic expression of PPARγ, indicating that PPARγ is directly involved in the regulation of SIRT1 stability. Furthermore, gain of MKP-7 function mimicked the effect of rosiglitazone on LPS-induced destabilization and ubiquitination of SIRT1. These results indicate that PPARγ-dependent upregulation of MKP-7 improves the stability of SIRT1 by inactivating JNK during inflammatory responses of LPS-activated macrophages.

  16. α-Hispanolol sensitizes hepatocellular carcinoma cells to TRAIL-induced apoptosis via death receptor up-regulation

    SciTech Connect

    Mota, Alba; Jiménez-Garcia, Lidia; Herránz, Sandra; Heras, Beatriz de las; Hortelano, Sonsoles

    2015-08-01

    Hispanolone derivatives have been previously described as anti-inflammatory and antitumoral agents. However, their effects on overcoming Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance remain to be elucidated. In this study, we analyzed the cytotoxic effects of the synthetic hispanolone derivative α-hispanolol (α-H) in several tumor cell lines, and we evaluated the induction of apoptosis, as well as the TRAIL-sensitizing potential of α-H in the hepatocellular carcinoma cell line HepG2. Our data show that α-H decreased cell viability in a dose-dependent manner in HeLa, MDA-MB231, U87 and HepG2 cell lines, with a more prominent effect in HepG2 cells. Interestingly, α-H had no effect on non-tumoral cells. α-H induced activation of caspase-8 and caspase-9 and also increased levels of the proapoptotic protein Bax, decreasing antiapoptotic proteins (Bcl-2, X-IAP and IAP-1) in HepG2 cells. Specific inhibition of caspase-8 abrogated the cascade of caspase activation, suggesting that the extrinsic pathway has a critical role in the apoptotic events induced by α-H. Furthermore, combined treatment of α-H with TRAIL enhanced apoptosis in HepG2 cells, activating caspase-8 and caspase-9. This correlated with up-regulation of both the TRAIL death receptor DR4 and DR5. DR4 or DR5 neutralizing antibodies abolished the effect of α-H on TRAIL-induced apoptosis, suggesting that sensitization was mediated through the death receptor pathway. Our results demonstrate that α-H induced apoptosis in the human hepatocellular carcinoma cell line HepG2 through activation of caspases and induction of the death receptor pathway. In addition, we describe a novel function of α-H as a sensitizer on TRAIL-induced apoptotic cell death in HepG2 cells. - Highlights: • α-Hispanolol induced apoptosis in the human hepatocellular carcinoma cell line HepG2. • α-Hispanolol induced activation of caspases and the death receptor pathway. • α-Hispanolol enhanced

  17. Upregulation of 5-HT2C receptors in hippocampus of pilocarpine-induced epileptic rats: antagonism by Bacopa monnieri.

    PubMed

    Krishnakumar, Amee; Nandhu, M S; Paulose, C S

    2009-10-01

    Emotional disturbances, depressive mood, anxiety, aggressive behavior, and memory impairment are the common psychiatric features associated with temporal lobe epilepsy (TLE). The present study was carried out to investigate the role of Bacopa monnieri extract in hippocampus of pilocarpine-induced temporal lobe epileptic rats through the 5-HT(2C) receptor in relation to depression. Our results showed upregulation of 5-HT(2C) receptors with a decreased affinity in hippocampus of pilocarpine-induced epileptic rats. Also, there was an increase in 5-HT(2C) gene expression and inositol triphosphate content in epileptic hippocampus. Carbamazepine and B. monnieri treatments reversed the alterations in 5-HT(2C) receptor binding, gene expression, and inositol triphosphate content in treated epileptic rats as compared to untreated epileptic rats. The forced swim test confirmed the depressive behavior pattern during epilepsy that was nearly completely reversed by B. monnieri treatment.

  18. Upregulation of PEDF expression by PARP inhibition contributes to the decrease in hyperglycemia-induced apoptosis in HUVECs

    SciTech Connect

    Chen Haibing; Jia Weiping; Xu Xun; Fan Ying; Zhu Dongqing; Wu Haixiang; Xie Zhenggao; Zheng Zhi

    2008-05-02

    Poly(ADP-ribose)polymerase (PARP) inhibitors decrease angiogenesis through reducing vascular endothelium growth factor (VEGF) induced proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs). In contrast to VEGF, pigment epithelium-derived factor (PEDF) has been demonstrated to act as a strong endogenous inhibitor of angiogenesis. Here, we show that PARP inhibition with a specific inhibitor PJ-34 or specific PARP antisense oligonucleotide upregulates hyperglycemia-induced PEDF expression in HUVECs in a dose-dependent manner. This results in the retard of activation of p38 MAP kinase and the concomitant decrease in cell apoptosis. These results give the first direct demonstration that PEDF might represent a target for PARP inhibition treatment and the effects of PEDF on endothelial cells growth are context dependent.

  19. Zoledronate upregulates MMP-9 and -13 in rat vascular smooth muscle cells by inducing oxidative stress

    PubMed Central

    Arun, Mehmet Zuhuri; Reel, Buket; Sala-Newby, Graciela B; Bond, Mark; Tsaousi, Aikaterini; Maskell, Perry; Newby, Andrew C

    2016-01-01

    Background Bisphosphonates, including zoledronate, target osteoclasts and are widely used in the treatment of osteoporosis and other bone resorption diseases, despite side effects that include damaging the stomach epithelium. Beneficial and adverse effects on other organ systems, including the cardiovascular system, have also been described and could impact on the use of bisphosphonates as therapeutic agents. Vascular smooth muscle cells (VSMCs) are major constituents of the normal vascular wall and have a key role in intimal thickening and atherosclerosis, in part by secreting MMPs that remodel the extracellular matrix and cleave cell surface proteins or secreted mediators. In this study, we investigated the effects of zoledronate on MMP expression. Methods Rat VSMCs were stimulated by PDGF (50 ng/mL) plus TNF-α (10 ng/mL) or left unstimulated for a further 24 hours in serum-free medium. In other series of experiments, cells were pre-treated either with SC-514 (50 μM) or with apocynin (20 nM) for 2 hours, then zoledronate (100 μM) was added into 2% fetal calf serum containing medium for 24 hours. Results and discussion Using isolated rat VSMCs in culture, zoledronate (100 μM) increased MMP-9 and -13 mRNA expressions but inhibited MMP-2 expression. MMP-9 and MMP-13 up-regulation was shown to depend on the NF-κB pathway; and this was activated by zoledronate. Furthermore, zoledronate elevated the levels of reactive oxygen species detected by either dichlorofluorescein in isolated VSMCs or lucigenin enhanced chemiluminescence in rat aortic rings in vitro. Apocynin, an inhibitor of NADPH oxidase, reversed NF-κB activation and MMP-9 and MMP-13 up-regulation by zoledronate. Conclusion We conclude that zoledronate increases MMP-9 and MMP-13 expressions in rat VSMCs dependent upon stimulation of the NF-κB pathway by reactive oxygen species. Effects on MMP expression may contribute to the pharmacologic profile of bisphosphonates. PMID:27143852

  20. Green tea diet decreases PCB 126-induced oxidative stress in mice by upregulating antioxidant enzymes

    PubMed Central

    Newsome, Bradley J; Petriello, Michael C; Han, Sung Gu; Murphy, Margaret O; Eske, Katryn E; Sunkara, Manjula; Morris, Andrew J; Hennig, Bernhard

    2013-01-01

    Superfund chemicals such as polychlorinated biphenyls pose a serious human health risk due to their environmental persistence and link to multiple diseases. Selective bioactive food components such as flavonoids have been shown to ameliorate PCB toxicity, but primarily in an in vitro setting. Here, we show that mice fed a green tea-enriched diet and subsequently exposed to environmentally relevant doses of coplanar PCB exhibit decreased overall oxidative stress primarily due to the upregulation of a battery of antioxidant enzymes. C57BL/6 mice were fed a low fat diet supplemented with green tea extract (GTE) for 12 weeks and exposed to 5 μmol PCB 126/kg mouse weight (1.63 mg/kg-day) on weeks 10, 11 and 12 (total body burden: 4.9 mg/kg). F2-Isoprostane and its metabolites, established markers of in vivo oxidative stress, measured in plasma via HPLC-MS/MS exhibited five-fold decreased levels in mice supplemented with GTE and subsequently exposed to PCB compared to animals on a control diet exposed to PCB. Livers were collected and harvested for both mRNA and protein analyses, and it was determined that many genes transcriptionally controlled by AhR and Nrf2 proteins were upregulated in PCB-exposed mice fed the green tea supplemented diet. An increased induction of genes such as SOD1, GSR, NQO1 and GST, key antioxidant enzymes, in these mice (green tea plus PCB) may explain the observed decrease in overall oxidative stress. A diet supplemented with green tea allows for an efficient antioxidant response in the presence of PCB 126 which supports the emerging paradigm that healthful nutrition may be able to bolster and buffer a physiological system against the toxicities of environmental pollutants. PMID:24378064

  1. Dexmedetomidine alleviates rat post-ischemia induced allodynia through GRK2 upregulation in superior cervical ganglia.

    PubMed

    Dong, Jing; Yang, Li; Tang, Jun; Zheng, Jijian

    2015-01-01

    A transient decrease in G protein-coupled receptor kinase 2 (GRK2) in nociceptors can produce long-lasting neuroplastic changes in nociceptor function, eventually enhancing and prolonging inflammatory hyperalgesia. Here, we investigated the effects of selective α2-adrenoceptor agonist dexmedetomidine (DMED) on GRK2 expression in superior cervical ganglion (SCG) in a rat model of complex regional pain syndrome type I (CRPS-I). The ipsilateral 50% paw withdrawal thresholds (PWTs) to mechanical stimuli decreased significantly starting from 24 h after ischemia-reperfusion (I/R) injury, and lasted for over 3 weeks; the ipsilateral cold allodynia scores, GRK2 protein and mRNA levels in SCGs all increased significantly. No significant differences were found in the contralateral side except GRK2 mRNA reduced significantly after 48 h I/R injury, but still higher than those in the ipsilateral side. Following daily injection of 10 μg/kg of DMED for a maximum of 7 days, the ipsilateral PWTs on days 1, 2, 7, 14, and 21 after DMED administration were significantly higher than those in control group; the GRK2 protein and mRNA expressions in the ipsilateral SCGs were also significantly upregulated; the ipsilateral cold allodynia scores were significantly reduced. No significant differences were found in the contralateral 50%PWTs, cold allodynia scores, and GRK2 protein level except GRK2 mRNA levels increased significantly on days 1 to 7 after DMED administration. Therefore, a transient decrease of GRK2 expression in SCG neurons might be involved in the development and maintenance of allodynia in CRPS-I and DMED might alleviate this allodynia through GRK2 upregulation in SCG neurons.

  2. DASH diet lowers blood pressure and lipid-induced oxidative stress in obesity.

    PubMed

    Lopes, Heno F; Martin, Kelley L; Nashar, Khaled; Morrow, Jason D; Goodfriend, Theodore L; Egan, Brent M

    2003-03-01

    Evidence suggests that obesity may raise blood pressure (BP) through oxidative stress-sensitive mechanisms and that the Dietary Approaches to Stop Hypertension combination diet (DASH-CD) may decrease BP by enhancing antioxidant capacity. To address this question, 12 obese patients with high-normal-to-stage 1 hypertension (hypertensives) and 12 lean normotensives were studied on their usual diets and after following the DASH-CD and a low-antioxidant diet in random sequence for 4 weeks each. Acute oxidative stress was induced by a 4-hour infusion of intralipid and heparin. Ferric-reducing activity of plasma (FRAP) and plasma F2-isoprostanes were measured as biomarkers of antioxidant capacity and oxidative stress, respectively. BP was lower in obese hypertensives on the DASH-CD than on the usual and low-antioxidant diets (-8.1+/-1.5/-7.4+/-1.6 mm Hg, P<0.05). BP did not change significantly in lean normotensives after 4 weeks on the DASH-CD but tended to rise on the low-antioxidant diet. FRAP on usual diets was higher in lean subjects than in obese subjects. FRAP increased in obese but not lean volunteers on the DASH-CD compared with usual diet, and the group difference disappeared. F2-isoprostanes increased from baseline during intralipid and heparin in both groups on the low-antioxidant diet but not in obese hypertensives on the DASH-CD. Among free-living obese hypertensives, the DASH-CD raises antioxidant capacity, lowers BP, and reduces oxidative stress induced by acute hyperlipidemia. The findings are consistent with evidence that elevated BP in obese subjects may reflect an imbalance between antioxidant capacity and oxidative stress that is improved by the DASH-CD.

  3. Obesity decreases the oxidant stress induced by tobacco smoke in a rat model.

    PubMed

    Montaño, Martha; Pérez-Ramos, J; Esquivel, A; Rivera-Rosales, R; González-Avila, G; Becerril, C; Checa, M; Ramos, C

    2016-09-01

    Obesity and emphysema are associated with low-grade systemic inflammation and oxidant stress. Assuming that the oxidant stress induced by emphysema would be decreased by obesity, we analyzed the oxidant/antioxidant state in a rat model combining both diseases simultaneously. Obesity was induced using sucrose, while emphysema by exposure to tobacco smoke. End-points evaluated were: body weight, abdominal fat, plasma dyslipidemia and malondialdehyde (MDA), insulin and glucose AUC, activities of Mn-superoxide dismutase (Mn-SOD), glutathione reductase (GR), glutathione transferase (GST) and glutathione peroxidase (GPx); lung MnSOD and 3-nitrotyrosine (3-NT) immunostaining, and expression of αV and β6 integrin subunits. In rats with obesity, the body weight, abdominal fat, plasma triglyceride levels, glucose AUC, insulin levels, GST activity, and αV and β6 integrin expressions were amplified. The rats with emphysema had lower values of body weight, abdominal fat, plasma insulin, triglycerides and glucose AUC but higher values of plasma MDA, GPx activity, and the lung expression of the αV and β6 integrins. The combination of obesity and emphysema compared to either condition alone led to diminished body weight, abdominal fat, plasma insulin MDA levels, GPx and GST activities, and αV and β6 integrin expressions; these parameters were all previously increased by obesity. Immunostaining for MnSOD augmented in all experimental groups, but the staining for 3-NT only increased in rats treated with tobacco alone or combined with sucrose. Results showed that obesity reduces oxidant stress and integrin expression, increasing antioxidant enzyme activities; these changes seem to partly contribute to a protective mechanism of obesity against emphysema development.

  4. NFATc3 Mediates Chronic Hypoxia-induced Pulmonary Arterial Remodeling with α-Actin Up-regulation

    PubMed Central

    de Frutos, S.; Spangler, R.; Alò, D.; González Bosc, L. V.

    2009-01-01

    Physiological responses to chronic hypoxia include polycythemia, pulmonary arterial remodeling and vasoconstriction. Chronic hypoxia causes pulmonary arterial hypertension leading to right ventricular hypertrophy and heart failure. During pulmonary hypertension, pulmonary arteries exhibit increased expression of smooth muscle-α-actin and -myosin heavy chain. NFATc3 (nuclear factor of activated T cells isoform c3), which is a Ca2+-dependent transcription factor, has been recently linked to smooth muscle phenotypic maintenance through the regulation of the expression of α-actin. The aim of this study was to determine if: a) NFATc3 is expressed in murine pulmonary arteries, b) hypoxia induces NFAT activation, c) NFATc3 mediates the up-regulation of α-actin during chronic hypoxia, and d) NFATc3 is involved in chronic hypoxia-induced pulmonary vascular remodeling. NFATc3 transcript and protein were found in pulmonary arteries. NFAT-luciferase reporter mice were exposed to normoxia (630 torr) or hypoxia (380 torr) for 2, 7 or 21 days. Exposure to hypoxia elicited a significant increase in luciferase activity and pulmonary arterial smooth muscle nuclear NFATc3 localization, demonstrating NFAT activation. Hypoxia induced up-regulation of α-actin and was prevented by the calcineurin/NFAT inhibitor, cyclosporin A (25 mg/Kg/day s.c.). In addition, NFATc3 knockout mice did not showed increased α-actin levels and arterial wall thickness after hypoxia. These results strongly suggest that NFATc3 plays a role in the chronic hypoxia-induced vascular changes that underlie pulmonary hypertension. PMID:17403661

  5. Effects of Maternal Linseed Oil Supplementation on Metabolic Parameters in Cafeteria Diet-induced Obese Rats.

    PubMed

    Benaissa, Nawel; Merzouk, Hafida; Merzouk, Sid Ahmed; Narce, Michel

    2015-04-01

    Because linseed oil may influence maternal and fetal metabolisms, we investigated its role in the modulation of lipid metabolism in cafeteria diet-induced obese rats and their offspring. Female Wistar rats were fed control or cafeteria food, which were either supplemented or not supplemented with linseed oil (5%) for 1 month before and during gestation. At parturition, serum and tissue lipids and enzyme activities were analyzed. Cafeteria diet induced adverse metabolic alterations in both mothers and offspring. Linseed oil improved metabolic status. In conclusion, linseed oil displayed health benefits by modulating tissue enzyme activities in both obese mothers and their newborns.

  6. Up-regulation of heme oxygenase-1 protects against cold injury-induced brain damage: a laboratory-based study.

    PubMed

    Shih, Ruey-Horng; Cheng, Shin-Ei; Tung, Wei-Hsuan; Yang, Chuen-Mao

    2010-08-01

    Heme oxygenase-1 (HO-1), a kind of stress protein, is critical for the protection against ischemic stroke and cerebrovascular endothelium damage. However, the effects of HO-1 on trauma-induced brain injury are still unknown. Hence, we attempted to use a cold injury-induced brain trauma (CIBT) model in mice, which provides for a well-established approach for assessing brain edema and blood-brain barrier breakdown. Additionally, we explored cultured mouse brain endothelial cells (bEnd.3) to investigate the protective effects of HO-1. HO-1 was induced by infection with a recombinant adenovirus carrying the human HO-1 gene or an inducer of HO-1 activity, cobalt protoporphyrin IX (CoPP). The recombinant adenovirus (3.5 x 10(7) PFU/mouse, i.v.) or CoPP (10 mg/kg, i.v.) significantly increased HO-1 protein expression and HO-1 enzyme activity in the cerebral cortex of the mice. We found that overexpression of HO-1 protected against cold injury-induced secondary damage and behavioral impairment. Up-regulation of HO-1 decreased brain edema and neutrophil infiltration induced by cold injury. These HO-1-dependent protecting effects were abrogated by pretreatment with the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP; 3 mg/kg, i.v.). HO-1 expression in the cerebral endothelium was observed by immunofluorescent staining. CoPP-induced (1 muM, 24 h) HO-1 protein expression was determined by western blotting in bEnd.3 cells. Enhanced HO-1 also protected against cold injury-induced cell loss and damage, which were respectively determined by GAPDH leakage into the cell medium and XTT assay in bEnd.3 cells. In summary, HO-1 overexpression appears to offer an effective neuroprotection against cold-induced secondary brain injury.

  7. Physical Exercise Counteracts Stress-induced Upregulation of Melanin-concentrating Hormone in the Brain and Stress-induced Persisting Anxiety-like Behaviors

    PubMed Central

    Kim, Tae-Kyung

    2016-01-01

    Chronic stress induces anxiety disorders, whereas physical exercise is believed to help people with clinical anxiety. In the present study, we investigated the mechanisms underlying stress-induced anxiety and its counteraction by exercise using an established animal model of anxiety. Mice treated with restraint for 2 h daily for 14 days exhibited anxiety-like behaviors, including social and nonsocial behavioral symptoms, and these behavioral impairments lasted for more than 12 weeks after the stress treatment was removed. Despite these lasting behavioral changes, wheel-running exercise treatment for 1 h daily from post-stress days 1 - 21 counteracted anxiety-like behaviors, and these anxiolytic effects of exercise persisted for more than 2 months, suggesting that anxiolytic effects of exercise stably induced. Repeated restraint treatment up-regulated the expression of the neuropeptide, melanin-concentrating hormone (MCH), in the lateral hypothalamus, hippocampus, and basolateral amygdala, the brain regions important for emotional behaviors. In an in vitro study, treatment of HT22 hippocampal cells with glucocorticoid increased MCH expression, suggesting that MCH upregulation can be initially triggered by the stress hormone, corticosterone. In contrast, post-stress treatment with wheel-running exercise reduced the stress-induced increase in MCH expression to control levels in the lateral hypothalamus, hippocampus and basolateral amygdala. Administration of an MCH receptor antagonist (SNAP94847) to stress-treated mice was therapeutic against stress-induced anxiety-like behaviors. These results suggest that repeated stress produces long-lasting anxiety-like behaviors and upregulates MCH in the brain, while exercise counteracts stress-induced MCH expression and persisting anxiety-like behaviors. PMID:27574483

  8. Ankaflavin: a natural novel PPARγ agonist upregulates Nrf2 to attenuate methylglyoxal-induced diabetes in vivo.

    PubMed

    Lee, Bao-Hong; Hsu, Wei-Hsuan; Chang, Yu-Ying; Kuo, Hsuan-Fu; Hsu, Ya-Wen; Pan, Tzu-Ming

    2012-12-01

    Ankaflavin (AK) is an active compound having anti-inflammatory, anti-cancer, antiatherosclerotic, and hypolipidemic effects. We have previously reported that AK acts as an antioxidant and antidiabetic drug; however, the mechanism by which AK prevents diabetes remains unknown. Hyperglycemia is associated with protein glycation, which produces advanced glycation end-products (AGEs). Methylglyoxal (MG)-a metabolite of carbohydrates-is believed to cause insulin resistance by inducing inflammation and pancreas damage. In this work, diabetes was induced in Wistar rats (4 weeks of age) by treating them with MG (600 mg/kg bw) for 4 weeks. We observed that AK (10mg/kg bw) exerted peroxisome proliferator-activated receptor-γ (PPARγ) agonist activity, thereby enhancing insulin sensitivity (as indicated by hepatic GLUT2 translocation, PTP1B suppression, and glucose uptake) by downregulating blood glucose and upregulating pancreatic and duodenal homeobox-1 and Maf-A expression and increasing insulin production in MG-induced rats. However, these effects were abolished by the administration of GW9662 (PPARγ antagonist), but the expression of hepatic heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) was not suppressed in MG-induced rats. Therefore, the nuclear factor erythroid-related factor-2 (Nrf2) activation was investigated. AK did not affect hepatic Nrf2 mRNA or protein expression but significantly increased Nrf2 phosphorylation (serine 40), which was accompanied by increased transcriptional activation of hepatic HO-1 and GCL. These data indicated that AK protected rats from oxidative stress resulting from MG-induced insulin resistance. In contrast, these effects were not detected when the rats were treated with the antidiabetic drug rosiglitazone (10mg/kg bw). Moreover, we found that AK did not inhibit the generation of AGEs in vitro; however, the glutathione (GSH) levels in liver and pancreas of MG-induced rats were elevated in rats administered AK. Therefore

  9. Laminin-511, inducer of hair growth, is down-regulated and its suppressor in hair growth, laminin-332 up-regulated in chemotherapy-induced alopecia

    PubMed Central

    Imanishi, Hisayoshi; Tsuruta, Daisuke; Tateishi, Chiharu; Sugawara, Koji; Paus, Ralf; Tsuji, Tsutomu; Ishii, Masamitsu; Ikeda, Kazuo; Kunimoto, Hiroyuki; Nakajima, Koichi; Jones, Jonathan C.R.; Kobayashi, Hiromi

    2010-01-01

    Background Chemotherapy-induced alopecia (CIA) has a devastating cosmetic effect, especially in the young. Recent data indicate that two major basement membrane components (laminin-332 and -511) of the skin have opposing effects on hair growth. Objective In this study, we examined the role and localization of laminin-332 and -511 in CIA. Methods We examined the expression of laminin-332 and -511 during the dystrophic catagen form of CIA induced in C57BL/6 mice by cyclophosphamide (CYP) treatment. Results Our data indicate that both laminin-332 and its receptor α6β4 integrin are up-regulated (both quantitatively and spatially) after mid to late dystrophic catagen around the outer root sheath (ORS) in the lower third of hair follicles in CIA. This up-regulation also occurs at the transcriptional level. In contrast, laminin-511 is down-regulated after mid dystrophic catagen at the protein level, with transcriptional inactivation of laminin-511 occurring transiently at the early dystrophic catagen stage in both epidermal and ORS keratinocytes. Laminin-511 expression correlates with expression of α3 integrin in CIA and we also demonstrate that laminin-511 can up-regulate the activity of the α3 integrin promoter in cultured keratinocytes. Injection of a laminin-511 rich protein extract, but not recombinant laminin-332, in the back skin of mice delays hair loss in CYP-induced CIA. Conclusions We propose that abrupt hair loss in CIA is, at least in part, caused by down-regulation of laminin-511 and up-regulation of laminin-332 at the transcriptional and translational levels. PMID:20211547

  10. Gamma delta T cells promote inflammation and insulin resistance during high fat diet-induced obesity in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gamma delta T cells are resident in adipose tissue and increase during diet-induced obesity. Their possible contribution to the inflammatory response that accompanies diet-induced obesity was investigated in mice after a 5-10 week high milk fat diet. The high milk fat diet resulted in significant in...

  11. CB1 Blockade Potentiates Down-Regulation of Lipogenic Gene Expression in Perirenal Adipose Tissue in High Carbohydrate Diet-Induced Obesity

    PubMed Central

    Gavito, Ana Luisa; Suárez, Juan; Pavón, Francisco Javier; Arrabal, Sergio; Romero-Cuevas, Miguel; Bautista, Dolores; Martínez, Ana; de Fonseca, Fernando Rodríguez; Serrano, Antonia; Baixeras, Elena

    2014-01-01

    De novo lipogenesis and hypercaloric diets are thought to contribute to increased fat mass, particularly in abdominal fat depots. CB1 is highly expressed in adipose tissue, and CB1-mediated signalling is associated with stimulation of lipogenesis and diet-induced obesity, though its contribution to increasing fat deposition in adipose tissue is controversial. Lipogenesis is regulated by transcription factors such as liver X receptor (LXR), sterol-response element binding protein (SREBP) and carbohydrate-responsive-element-binding protein (ChREBP). We evaluated the role of CB1 in the gene expression of these factors and their target genes in relation to lipogenesis in the perirenal adipose tissue (PrAT) of rats fed a high-carbohydrate diet (HCHD) or a high-fat diet (HFD). Both obesity models showed an up-regulated gene expression of CB1 and Lxrα in this adipose pad. The Srebf-1 and ChREBP gene expressions were down-regulated in HFD but not in HCHD. The expression of their target genes encoding for lipogenic enzymes showed a decrease in diet-induced obesity and was particularly dramatic in HFD. In HCHD, CB1 blockade by AM251 reduced the Srebf-1 and ChREBP expression and totally abrogated the remnant gene expression of their target lipogenic enzymes. The phosphorylated form of the extracellular signal-regulated kinase (ERK-p), which participates in the CB1-mediated signalling pathway, was markedly present in the PrAT of obese rats. ERK-p was drastically repressed by AM251 indicating that CB1 is actually functional in PrAT of obese animals, though its activation loses the ability to stimulate lipogenesis in PrAT of obese rats. Even so, the remnant expression levels of lipogenic transcription factors found in HCHD-fed rats are still dependent on CB1 activity. Hence, in HCHD-induced obesity, CB1 blockade may help to further potentiate the reduction of lipogenesis in PrAT by means of inducing down-regulation of the ChREBP and Srebf-1 gene expression, and consequently in

  12. CB1 blockade potentiates down-regulation of lipogenic gene expression in perirenal adipose tissue in high carbohydrate diet-induced obesity.

    PubMed

    Vida, Margarita; Rivera, Patricia; Gavito, Ana Luisa; Suárez, Juan; Pavón, Francisco Javier; Arrabal, Sergio; Romero-Cuevas, Miguel; Bautista, Dolores; Martínez, Ana; de Fonseca, Fernando Rodríguez; Serrano, Antonia; Baixeras, Elena

    2014-01-01

    De novo lipogenesis and hypercaloric diets are thought to contribute to increased fat mass, particularly in abdominal fat depots. CB1 is highly expressed in adipose tissue, and CB1-mediated signalling is associated with stimulation of lipogenesis and diet-induced obesity, though its contribution to increasing fat deposition in adipose tissue is controversial. Lipogenesis is regulated by transcription factors such as liver X receptor (LXR), sterol-response element binding protein (SREBP) and carbohydrate-responsive-element-binding protein (ChREBP). We evaluated the role of CB1 in the gene expression of these factors and their target genes in relation to lipogenesis in the perirenal adipose tissue (PrAT) of rats fed a high-carbohydrate diet (HCHD) or a high-fat diet (HFD). Both obesity models showed an up-regulated gene expression of CB1 and Lxrα in this adipose pad. The Srebf-1 and ChREBP gene expressions were down-regulated in HFD but not in HCHD. The expression of their target genes encoding for lipogenic enzymes showed a decrease in diet-induced obesity and was particularly dramatic in HFD. In HCHD, CB1 blockade by AM251 reduced the Srebf-1 and ChREBP expression and totally abrogated the remnant gene expression of their target lipogenic enzymes. The phosphorylated form of the extracellular signal-regulated kinase (ERK-p), which participates in the CB1-mediated signalling pathway, was markedly present in the PrAT of obese rats. ERK-p was drastically repressed by AM251 indicating that CB1 is actually functional in PrAT of obese animals, though its activation loses the ability to stimulate lipogenesis in PrAT of obese rats. Even so, the remnant expression levels of lipogenic transcription factors found in HCHD-fed rats are still dependent on CB1 activity. Hence, in HCHD-induced obesity, CB1 blockade may help to further potentiate the reduction of lipogenesis in PrAT by means of inducing down-regulation of the ChREBP and Srebf-1 gene expression, and consequently in

  13. Arctigenin Inhibits Adipogenesis by Inducing AMPK Activation and Reduces Weight Gain in High-Fat Diet-Induced Obese Mice.

    PubMed

    Han, Yo-Han; Kee, Ji-Ye; Park, Jinbong; Kim, Hye-Lin; Jeong, Mi-Young; Kim, Dae-Seung; Jeon, Yong-Deok; Jung, Yunu; Youn, Dong-Hyun; Kang, JongWook; So, Hong-Seob; Park, Raekil; Lee, Jong-Hyun; Shin, Soyoung; Kim, Su-Jin; Um, Jae-Young; Hong, Seung-Heon

    2016-09-01

    Although arctigenin (ARC) has been reported to have some pharmacological effects such as anti-inflammation, anti-cancer, and antioxidant, there have been no reports on the anti-obesity effect of ARC. The aim of this study is to investigate whether ARC has an anti-obesity effect and mediates the AMP-activated protein kinase (AMPK) pathway. We investigated the anti-adipogenic effect of ARC using 3T3-L1 pre-adipocytes and human adipose tissue-derived mesenchymal stem cells (hAMSCs). In high-fat diet (HFD)-induced obese mice, whether ARC can inhibit weight gain was investigated. We found that ARC reduced weight gain, fat pad weight, and triglycerides in HFD-induced obese mice. ARC also inhibited the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα) in in vitro and in vivo. Furthermore, ARC induced the AMPK activation resulting in down-modulation of adipogenesis-related factors including PPARγ, C/EBPα, fatty acid synthase, adipocyte fatty acid-binding protein, and lipoprotein lipase. This study demonstrates that ARC can reduce key adipogenic factors by activating the AMPK in vitro and in vivo and suggests a therapeutic implication of ARC for obesity treatment. J. Cell. Biochem. 117: 2067-2077, 2016. © 2016 Wiley Periodicals, Inc.

  14. Methamphetamine and 3,4-methylenedioxymethamphetamine interact with central nicotinic receptors and induce their up-regulation

    SciTech Connect

    Garcia-Rates, Sara; Camarasa, Jordi; Escubedo, Elena; Pubill, David

    2007-09-15

    Previous work from our group indicated that {alpha}7 nicotinic acetylcholine receptors ({alpha}7 nAChR) potentially play a role in methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA) neurotoxicity. The aims of the present study were two-fold: (1) to demonstrate the interaction of METH and MDMA with homomeric {alpha}7 nAChR ([{sup 3}H]methyllycaconitine binding) and other heteromeric subtypes ([{sup 3}H]epibatidine binding); and (2) to show the effects of amphetamine derivative pretreatment on the density of binding sites. METH and MDMA displaced [{sup 3}H]methyllycaconitine and [{sup 3}H]epibatidine binding in membranes from NGF-differentiated PC 12 cells and mouse brain, with K{sub i} values in the micromolar range, MDMA revealing a greater affinity than METH. In addition, METH and MDMA induced a time- and concentration-dependent increase in [{sup 3}H]methyllycaconitine and [{sup 3}H]epibatidine binding; which had already been apparent after 6 h of pretreatment, and which peaked in differentiated PC 12 cells after 48 h. The highest increases were found in [{sup 3}H]epibatidine binding, with MDMA inducing higher increases than METH. Treatment with METH and MDMA increased B{sub max} of high-affinity sites for both radioligands without affecting K{sub d}. The heightened binding was inhibited by pretreatment with cycloheximide, suggesting the participation of newly synthesised proteins while inhibition of protein trafficking to plasma membrane did not block up-regulation. The effects of protein kinase and cyclophilin inhibitors on such up-regulation were explored, revealing a rapid, differential and complex regulation, similar to that described for nicotinic ligands. All of these results demonstrate that METH and MDMA have affinity for, and can interact with, nAChR, inducing their up-regulation, specially when higher doses are used. Such effects may have a role in METH- and MDMA-induced neurotoxicity, cholinergic neurotransmission, and in processes

  15. Caveolin-1 mediates tissue plasminogen activator-induced MMP-9 up-regulation in cultured brain microvascular endothelial cells.

    PubMed

    Jin, Xinchun; Sun, Yanyun; Xu, Ji; Liu, Wenlan

    2015-03-01

    Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates blood-brain barrier injury and increases the risk of symptomatic cerebral hemorrhage. The mechanism through which tPA enhances MMP-9 activity is not well understood. Here we report an important role of caveolin-1 in mediating tPA-induced MMP-9 synthesis. Brain microvascular endothelial cell line bEnd3 cells were incubated with 5 or 20 μg/ml tPA for 24 hrs before analyzing MMP-9 levels in the conditioned media and cellular extracts by gelatin zymography. tPA at a dose of 20 μg/mL tPA, but not 5 μg/mL, significantly increased MMP-9 level in cultured media while decreasing it in cellular extracts. Concurrently, tPA treatment induced a 2.3-fold increase of caveolin-1 protein levels in endothelial cells. Interestingly, knockdown of Cav-1 with siRNA inhibited tPA-induced MMP-9 mRNA up-regulation and MMP-9 increase in the conditioned media, but did not affect MMP-9 decrease in cellular extracts. These results suggest that caveolin-1 critically contributes to tPA-mediated MMP-9 up-regulation, but may not facilitate MMP-9 secretion in endothelial cells. Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates ischemic blood brain barrier (BBB) injury and increases the risk of symptomatic cerebral hemorrhage. Our results suggest a novel mechanism underlying this tPA-MMP 9 axis. In response to tPA treatment, caveolin-1 protein levels increased in endothelial cells, which mediate MMP-9 mRNA up-regulation and its secretion into extracellular space. Caveolin-1 may, however, not facilitate MMP-9 secretion in endothelial cells. Our data suggest caveolin-1 as a novel therapeutic target for protecting the BBB against ischemic damage. The schematic outlines tPA-induced MMP-9 upreguation.

  16. Diet-induced obesity causes innate airway hyperresponsiveness to methacholine and enhances ozone-induced pulmonary inflammation.

    PubMed

    Johnston, Richard A; Theman, Todd A; Lu, Frank L; Terry, Raya D; Williams, Erin S; Shore, Stephanie A

    2008-06-01

    We previously reported that genetically obese mice exhibit innate airway hyperresponsiveness (AHR) and enhanced ozone (O(3))-induced pulmonary inflammation. Such genetic deficiencies in mice are rare in humans, and they may not be representative of human obesity. Thus the purpose of this study was to determine the pulmonary phenotype of mice with diet-induced obesity (DIO), which more closely mimics the cause of human obesity. Therefore, wild-type C57BL/6 mice were reared from the time of weaning until at least 30 wk of age on diets in which either 10 or 60% of the calories are derived from fat in the form of lard. Body mass was approximately 40% greater in mice fed 60 vs. 10% fat diets. Baseline airway responsiveness to intravenous methacholine, measured by forced oscillation, was greater in mice fed 60 vs. 10% fat diets. We also examined lung permeability and inflammation after exposure to room air or O(3) (2 parts/million for 3 h), an asthma trigger. Four hours after the exposure ended, O(3)-induced increases in bronchoalveolar lavage fluid protein, interleukin-6, KC, macrophage inflammatory protein-2, interferon-gamma-inducible protein-10, and eotaxin were greater in mice fed 60 vs. 10% fat diets. Innate AHR and augmented responses to O(3) were not observed in mice raised from weaning until 20-22 wk of age on a 60% fat diet. These results indicate that mice with DIO exhibit innate AHR and enhanced O(3)-induced pulmonary inflammation, similar to genetically obese mice. However, mice with DIO must remain obese for an extended period of time before this pulmonary phenotype is observed.

  17. ACSL3 and GSK-3β are essential for lipid upregulation induced by endoplasmic reticulum stress in liver cells.

    PubMed

    Chang, Yung-Sheng; Tsai, Chien-Ting; Huangfu, Chien-An; Huang, Wen-Ya; Lei, Huan-Yao; Lin, Chiou-Feng; Su, Ih-Jen; Chang, Wen-Tsan; Wu, Pei-Huan; Chen, Ya-Ting; Hung, Jui-Hsiang; Young, Kung-Chia; Lai, Ming-Derg

    2011-03-01

    The endoplasmic reticulum (ER) is essential for lipid biosynthesis, and stress signals in this organelle are thought to alter lipid metabolism. Elucidating the mechanisms that underlie the dysregulation of lipid metabolism in hepatocytes may lead to novel therapeutic approaches for the treatment of lipid accumulation. We first tested the effects of several inhibitors on lipid dysregulation induced by tunicamycin, an ER stress inducer. Triacsin C, an inhibitor of long-chain acyl-CoA synthetase (ACSL) 1, 3, and 4, was the most potent among these inhibitors. We then analyzed the expression of the ACSL family during ER stress. The expression of ACSL3 was induced by ER stress in HuH-7 cells and in mice livers. ACSL3 shRNA, but not ACSL1 shRNA, inhibited the induction of lipid accumulation. GSK-3β inhibitors attenuated ACSL3 expression and the lipid accumulation induced by ER stress in HuH-7 cells. shRNA that target GSK-3β also inhibited the upregulation of ACSL3 and lipid accumulation in HuH-7 and HepG2 cells. The hepatitis B virus mutant large surface protein, which is known to induce ER stress, increased the lipid content of cells. Similarly, Triacsin C, and GSK-3β inhibitors abrogated the lipid dysregulation caused by the hepatitis B virus mutant large surface protein. Altogether, ACSL3 and GSK-3β represent novel therapeutic targets for lipid dysregulation by ER stress.

  18. β2-Adrenogenic signaling regulates NNK-induced pancreatic cancer progression via upregulation of HIF-1α

    PubMed Central

    Ma, Jiguang; Chen, Xin; Sheng, Liang; Jiang, Zhengdong; Nan, Ligang; Xu, Qinhong; Duan, Wanxing; Wang, Zheng; Li, Xuqi; Wu, Zheng; Wu, Erxi; Ma, Qingyong; Huo, Xiongwei

    2016-01-01

    Cigarette smoking is a risk factor for pancreatic cancer. It is suggested that 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco-specific nitrosamine, mediates the carcinogenic action of cigarette smoking by promoting cancer growth. In the present study, we show that smoking, HIF-1α expression and β2-adrenogenic receptor (β2-AR) expression are negatively correlated with the overall survival of pancreatic cancer patients. Moreover, HIF-1α expression and β2-AR expression are positively correlated with smoking status, different histological differentiation and among the tumor node metastasis (TNM) stages in pancreatic cancer patients. NNK increases HIF-1α expression in pancreatic cancer in vitro and in vivo. Furthermore, knockdown of HIF-1α and ICI118, 551 (a β2-AR selective antagonist) abrogates NNK-induced pancreatic cancer proliferation and invasion in vitro and inhibits NNK-induced pancreatic cancer growth in vivo. However, using CoCl2 (a HIF-1α stabilizing agent which decreases HIF-1α degradation under normoxia conditions) reverses ICI118, 551 induced effects under NNK exposure. Thus, our data indicate that β2-AR signaling regulates NNK-induced pancreatic cancer progression via upregulation of HIF-1α. Taken together, β2-AR signaling and HIF-1α may represent promising therapeutic targets for preventing smoking induced pancreatic cancer progression. PMID:26497365

  19. Phloretin Prevents High-Fat Diet-Induced Obesity and Improves Metabolic Homeostasis.

    PubMed

    Alsanea, Sary; Gao, Mingming; Liu, Dexi

    2017-02-14

    Reactive oxygen species generated as a by-product in metabolism play a central role in the development of obesity and obesity-related metabolic complications. The objective of the current study is to explore the possibility to block obesity and improve metabolic homeostasis via phloretin, a natural antioxidant product from apple tree leaves and Manchurian apricot. Both preventive and therapeutic activities of phloretin were assessed using a high-fat diet-induced obesity mouse model. Phloretin was injected intraperitoneally twice weekly into regular and obese mice fed a high-fat diet. The effects of phloretin treatment on body weight and composition, fat content in the liver, glucose and lipid metabolism, and insulin resistance were monitored and compared to the control animals. Phloretin treatment significantly blocks high-fat diet-induced weight gain but did not induce weight loss in obese animals. Phloretin improved glucose homeostasis and insulin sensitivity and alleviated hepatic lipid accumulation. RT-PCR analysis showed that phloretin treatment suppresses expression of macrophage markers (F4/80 and Cd68) and pro-inflammatory genes (Mcp-1 and Ccr2) and enhances adiponectin gene expression in white adipose tissue. In addition, phloretin treatment elevated the expression of fatty acid oxidation genes such as carnitine palmitoyltransferase 1a and 1b (Cpt1a and Cpt1b) and reduced expression of monocyte chemoattractant protein-1 (Mcp-1), de novo lipogenesis transcriptional factor peroxisome proliferator-activated receptor-γ 2 (Pparγ2), and its target monoacylglycerol O-acyltransferase (Mgat-1) genes. These results provide direct evidence to support a possible use of phloretin for mitigation of obesity and maintenance of metabolic homeostasis.

  20. Aerobic training suppresses exercise-induced lipid peroxidation and inflammation in overweight/obese adolescent girls.

    PubMed

    Youssef, Hala; Groussard, Carole; Lemoine-Morel, Sophie; Pincemail, Joel; Jacob, Christophe; Moussa, Elie; Fazah, Abdallah; Cillard, Josiane; Pineau, Jean-Claude; Delamarche, Arlette

    2015-02-01

    This study aimed to determine whether aerobic training could reduce lipid peroxidation and inflammation at rest and after maximal exhaustive exercise in overweight/obese adolescent girls. Thirty-nine adolescent girls (14-19 years old) were classified as nonobese or overweight/obese and then randomly assigned to either the nontrained or trained group (12-week multivariate aerobic training program). Measurements at the beginning of the experiment and at 3 months consisted of body composition, aerobic fitness (VO2peak) and the following blood assays: pre- and postexercise lipid peroxidation (15F2a-isoprostanes [F2-Isop], lipid hydroperoxide [ROOH], oxidized LDL [ox-LDL]) and inflammation (myeloperoxidase [MPO]) markers. In the overweight/ obese group, the training program significantly increased their fat-free mass (FFM) and decreased their percentage of fat mass (%FM) and hip circumference but did not modify their VO2peak. Conversely, in the nontrained overweight/obese group, weight and %FM increased, and VO2peak decreased, during the same period. Training also prevented exercise-induced lipid peroxidation and/or inflammation in overweight/obese girls (F2-Isop, ROOH, ox-LDL, MPO). In addition, in the trained overweight/obese group, exercise-induced changes in ROOH, ox-LDL and F2-Isop were correlated with improvements in anthropometric parameters (waist-to-hip ratio, %FM and FFM). In conclusion aerobic training increased tolerance to exercise-induced oxidative stress in overweight/obese adolescent girls partly as a result of improved body composition.

  1. The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice

    SciTech Connect

    Hao, Chan-Juan; Cheng, Xue-Jia; Xia, Hong-Fei Ma, Xu

    2012-08-15

    Epidemiology studies indicate that exposure to endocrine disruptors during developmental “window” contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders. -- Highlights: ► DES induced adipocyte differentiation in a dose-dependent manner in 3T3-L1 cells. ► DES activated adipogenic critical regulators and markers in vitro and in vivo. ► Perinatal exposure to DES led to the obese phenotype in female offspring. ► DES might be a potential chemical stressor for obesity and obesity-related disorders.

  2. Resolution of inflammation in obesity-induced liver disease.

    PubMed

    Rius, Bibiana; López-Vicario, Cristina; González-Périz, Ana; Morán-Salvador, Eva; García-Alonso, Verónica; Clária, Joan; Titos, Esther

    2012-01-01

    Low-grade inflammation in adipose tissue is recognized as a critical event in the development of obesity-related co-morbidities. This chronic inflammation is powerfully augmented through the infiltration of macrophages, which together with adipocytes, perpetuate a vicious cycle of inflammatory cell recruitment and secretion of free fatty acids and deleterious adipokines that predispose to greater incidence of metabolic complications. In the last decade, many factors have been identified to contribute to mounting unresolved inflammation in obese adipose tissue. Among them, pro-inflammatory lipid mediators (i.e., leukotrienes) derived from the omega-6 polyunsaturated arachidonic acid have been shown to play a prominent role. Of note, the same lipid mediators that initially trigger the inflammatory response also signal its termination by stimulating the formation of anti-inflammatory signals. Resolvins and protectins derived from the omega-3 polyunsaturated docosahexaenoic and eicosapentaenoic acids have emerged as a representative family of this novel class of autacoids with dual anti-inflammatory and pro-resolving properties that act as "stop-signals" of the inflammatory response. This review discusses the participation of these endogenous autacoids in the resolution of adipose tissue inflammation, with a special emphasis in the amelioration of obesity-related metabolic dysfunctions, namely insulin resistance and non-alcoholic fatty liver disease.

  3. Curcumin inhibits cell growth and induces cell apoptosis through upregulation of miR-33b in gastric cancer.

    PubMed

    Sun, Qianqian; Zhang, Wenjing; Guo, Yanjie; Li, Zhuyao; Chen, Xiaonan; Wang, Yuanyuan; Du, Yuwen; Zang, Wenqiao; Zhao, Guoqiang

    2016-10-01

    In this work, the in vitro experiments about biological mechanisms of curcumin were conducted using the gastric cancer cell lines SGC-7901 and BGC-823. After 24-h exposure to curcumin at the concentrations of 5, 10, 15, 20, and 40 μmol/L, two cells showed the decreased proliferation and increased apoptosis abilities. Real-time PCR, Cell Counting Kit-8 (CCK-8) assay, western blotting, and cell apoptosis assay were used to further study the underlying mechanisms of curcumin. The first stage of our studies showed that curcumin affected the expression of miR-33b, which, in turn, affected the expression of the X-linked inhibitor of apoptosis protein (XIAP) messenger RNA (mRNA). Next, curcumin was also identified to regulate the proliferation and apoptosis of SGC-7901 and BGC-823 cells. Further bioinformatics analysis and luciferase reporter assays proved that XIAP was one of the target genes of miR-33b. In the next stage, SGC-7901 and BGC-823 cells were treated with 20 μL curcumin, miR-33b mimics, and small interfering RNA (siRNA) of XIAP, respectively. The results showed that curcumin had similar effects on cell growth and apoptosis as the upregulation of miR-33b and the upregulation of the siRNA of XIAP. The results that followed from the restore experiments showed that curcumin affected cell growth and apoptosis presumably by upregulating the XIAP targeting in gastric cancer. Collectively, our results indicate that curcumin-miR-33b-XIAP coupling might be an important mechanism by which curcumin induces the apoptosis of SGC-7901 and BGC-823 cells.

  4. Pregnancy-induced up-regulation of aquaporin-4 protein in brain and its role in eclampsia.

    PubMed

    Quick, Allison M; Cipolla, Marilyn J

    2005-02-01

    Neurologic complications of eclampsia are thought to be similar to hypertensive encephalopathy in which an acute, excessive elevation in blood pressure causes blood-brain barrier (BBB) disruption and edema formation. Because women who develop eclampsia are in general normotensive and asymptomatic prior to pregnancy, we hypothesized that pregnancy alone predisposes the brain to edema formation by up-regulation of aquaporin 4 (AQP4), a water channel in the brain that has been shown to positively correlate with edema formation. To test this hypothesis, we compared localization (immunohistochemistry), mRNA (RT-PCR), and protein levels (Western analysis) of AQP4 in brains from Sprague Dawley rats that were nonpregnant (NP, proestrous), mid-pregnant (MP, days 9-10), late-pregnant (LP, days 19-20), and postpartum (PP, days 3-4). AQP4 mRNA was detected in the brains of all the animals and was localized primarily around the brain parenchymal blood vessels, strongly implicating its role in BBB function. Western analysis revealed that the major AQP4 band at approximately 32 kDa was significantly elevated in MP, LP, and PP animals compared with NP by 9-, 22-, and 17-fold, respectively. These results suggest that pregnancy and the postpartum state up-regulate AQP4 protein located around the intraparenchymal blood vessels, a consequence that could promote edema formation when blood pressure is acutely and excessively elevated, as during eclampsia.-Quick, A. M., Cipolla, M. J. Pregnancy-induced up-regulation of aquaporin-4 protein in brain and its role in eclampsia.

  5. Immunomodulatory drugs act as inhibitors of DNA methyltransferases and induce PU.1 up-regulation in myeloma cells.

    PubMed

    Endo, Shinya; Amano, Masayuki; Nishimura, Nao; Ueno, Niina; Ueno, Shikiko; Yuki, Hiromichi; Fujiwara, Shiho; Wada, Naoko; Hirata, Shinya; Hata, Hiroyuki; Mitsuya, Hiroaki; Okuno, Yutaka

    2016-01-08

    Immunomodulatory drugs (IMiDs) such as thalidomide, lenalidomide, and pomalidomide are efficacious in the treatment of multiple myeloma and significantly prolong their survival. However, the mechanisms of such effects of IMiDs have not been fully elucidated. Recently, cereblon has been identified as a target binding protein of thalidomide. Lenalidomide-resistant myeloma cell lines often lose the expression of cereblon, suggesting that IMiDs act as an anti-myeloma agent through interacting with cereblon. Cereblon binds to damaged DNA-binding protein and functions as a ubiquitin ligase, inducing degradation of IKZF1 and IKZF3 that are essential transcription factors for B and T cell development. Degradation of both IKZF1 and IKZF3 reportedly suppresses myeloma cell growth. Here, we found that IMiDs act as inhibitors of DNA methyltransferases (DMNTs). We previously reported that PU.1, which is an ETS family transcription factor and essential for myeloid and lymphoid development, functions as a tumor suppressor in myeloma cells. PU.1 induces growth arrest and apoptosis of myeloma cell lines. In this study, we found that low-dose lenalidomide and pomalidomide up-regulate PU.1 expression through inducing demethylation of the PU.1 promoter. In addition, IMiDs inhibited DNMT1, DNMT3a, and DNMT3b activities in vitro. Furthermore, lenalidomide and pomalidomide decreased the methylation status of the whole genome in myeloma cells. Collectively, IMiDs exert demethylation activity through inhibiting DNMT1, 3a, and 3b, and up-regulating PU.1 expression, which may be one of the mechanisms of the anti-myeloma activity of IMiDs.

  6. Anabolic Effect of Insulin Therapy on the Bone: Osteoprotegerin and Osteocalcin Up-Regulation in Streptozotocin-Induced Diabetic Rats.

    PubMed

    Bortolin, Raul Hernandes; Freire Neto, Francisco Paulo; Arcaro, Carlos Alberto; Bezerra, João Felipe; da Silva, Flávio Santos; Ururahy, Marcela Abbott Galvão; Souza, Karla Simone da Costa; Lima, Valeria Morgiana Gualberto Duarte Moreira; Luchessi, André Ducati; Lima, Francisco Pignataro; Lia Fook, Marcus Vinicius; da Silva, Bartolomeu Jorge; Almeida, Maria das Graças; Abreu, Bento João; de Rezende, Luciana Augusto; de Rezende, Adriana Augusto

    2017-03-01

    Type 1 diabetes mellitus (T1DM) is associated with several skeletal alterations, particularly in conditions of poor glycaemic control. Insulin therapy is the major conservative treatment for T1DM; however, the effects of this hormone on bone markers of T1DM rats are limited, and the regulatory mechanisms remain elusive. Therefore, the evaluation of molecular and non-molecular parameters in a chronic animal model of T1DM-induced bone loss, treated with and without insulin, may help in elucidating the insulin mechanisms. Male Wistar rats were assigned into three groups: control, T1DM (T1DM rats induced with streptozotocin [STZ] at 40 mg/kg intravenously) and T1DM plus insulin therapy (T1DMI). After 8 weeks, we evaluated the serum biochemical, tibia histomorphometric and biomechanical parameters, as well as the gene expression of the receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and osteocalcin (OC) of femur mRNA. Compared with T1DM, the T1DMI group showed less bone loss, which was revealed by the increased trabecular width (TbWi, p < 0.001) and trabecular bone area (BAr, p < 0.01), reduced trabecular separation (TbSp, p < 0.01) and increased Young's modulus (p < 0.05). Moreover, molecular analyses indicated that the expression of OPG and OC was up-regulated (p < 0.001 and p < 0.05, respectively). In summary, the up-regulation of OPG and OC in the T1DMI group supports an anabolic effect of insulin, which was demonstrated by the maintenance of bone architecture and flexibility. These results suggest that insulin therapy may prevent T1DM-induced bone loss via the effects on the bone formation.

  7. Epidrug-induced upregulation of functional somatostatin type 2 receptors in human pancreatic neuroendocrine tumor cells.

    PubMed

    Veenstra, Marije J; van Koetsveld, Peter M; Dogan, Fadime; Farrell, William E; Feelders, Richard A; Lamberts, Steven W J; de Herder, Wouter W; Vitale, Giovanni; Hofland, Leo J

    2016-05-19

    Somatostatin receptors are a pivotal target for treatment of pancreatic neuroendocrine tumors (pNET), either with somatostatin analogues (SSA) or radiolabeled SSA. The highest affinity target for the most commonly used SSA is the somatostatin receptor type 2 (sst2). An important factor that may complicate treatment efficacy, is the variable number of receptors expressed on pNETs. Gene expression is subject to complex regulation, in which epigenetics has a central role. In this study we explored the possible role of epigenetic modifications in the variations in sst2 expression levels in two human pNET cell lines, BON-1 and QGP-1. We found upregulation of sst2 mRNA after treatment with the epidrugs 5-aza-2'-deoxycytidine (5-aza-dC) and valproic acid (VPA), an increased uptake of radiolabeled octreotide, as well as increased sensitivity to the SSA octreotide in functional cAMP inhibition. At epigenetic level we observed low methylation levels of the sst2 gene promoter region irrespective of expression. Activating histone mark H3K9Ac can be regulated with epidrug treatment, with an angle of effect corresponding to the effect on mRNA expression. Repressive histone mark H3K27me3 is not regulated by either 5-aza-dC or VPA. We conclude that epidrug treatment, in particular with combined 5-aza-dC and VPA treatment, might hold promise for improving and adding to current SSA treatment strategies of patients with pNETs.

  8. Chemoradiotherapy-induced upregulation of PD-1 antagonizes immunity to HPV-related oropharyngeal cancer.

    PubMed

    Parikh, Falguni; Duluc, Dorothée; Imai, Naoko; Clark, Amelia; Misiukiewicz, Krzys; Bonomi, Marcello; Gupta, Vishal; Patsias, Alexis; Parides, Michael; Demicco, Elizabeth G; Zhang, David Y; Kim-Schulze, Seunghee; Kao, Johnny; Gnjatic, Sacha; Oh, Sangkon; Posner, Marshall R; Sikora, Andrew G

    2014-12-15

    While viral antigens in human papillomavirus (HPV)-related oropharyngeal cancer (HPVOPC) are attractive targets for immunotherapy, the effects of existing standard-of-care therapies on immune responses to HPV are poorly understood. We serially sampled blood from patients with stage III-IV oropharyngeal cancer undergoing concomitant chemoradiotherapy with or without induction chemotherapy. Circulating immunocytes including CD4(+) and CD8(+) T cells, regulatory T cells (Treg), and myeloid-derived suppressor cells (MDSC) were profiled by flow cytometry. Antigen-specific T-cell responses were measured in response to HPV16 E6 and E7 peptide pools. The role of PD-1 signaling in treatment-related immunosuppression was functionally defined by performing HPV-specific T-cell assays in the presence of blocking antibody. While HPV-specific T-cell responses were present in 13 of 18 patients before treatment, 10 of 13 patients lost these responses within 3 months after chemoradiotherapy. Chemoradiotherapy decreased circulating T cells and markedly elevated MDSCs. PD-1 expression on CD4(+) T cells increased by nearly 2.5-fold after chemoradiotherapy, and ex vivo culture with PD-1-blocking antibody enhanced HPV-specific T-cell responses in 8 of 18 samples tested. Chemoradiotherapy suppresses circulating immune responses in patients with HPVOPC by unfavorably altering effector:suppressor immunocyte ratios and upregulating PD-1 expression on CD4(+) T cells. These data strongly support testing of PD-1-blocking agents in combination with standard-of-care chemoradiotherapy for HPVOPC.

  9. Gut microbiota, intestinal permeability, obesity-induced inflammation, and liver injury.

    PubMed

    Frazier, Thomas H; DiBaise, John K; McClain, Craig J

    2011-09-01

    Obesity and its metabolic complications are major health problems in the United States and worldwide, and increasing evidence implicates the microbiota in these important health issues. Indeed, it appears that the microbiota function much like a metabolic "organ," influencing nutrient acquisition, energy homeostasis, and, ultimately, the control of body weight. Moreover, alterations in gut microbiota, increased intestinal permeability, and metabolic endotoxemia likely play a role in the development of a chronic low-grade inflammatory state in the host that contributes to the development of obesity and associated chronic metabolic diseases such as nonalcoholic fatty liver disease. Supporting these concepts are the observations that increased gut permeability, low-grade endotoxemia, and fatty liver are observed in animal models of obesity caused by either high-fat or high-fructose feeding. Consistent with these observations, germ-free mice are protected from obesity and many forms of liver injury. Last, many agents that affect gut flora/permeability, such as probiotics/prebiotics, also appear to affect obesity and certain forms of liver injury in animal model systems. Here the authors review the role of the gut microbiota and metabolic endotoxemia-induced inflammation in the development of obesity and liver injury, with special reference to the intensive care unit setting.

  10. Response style and vulnerability to anger-induced eating in obese adults.

    PubMed

    Appelhans, Bradley M; Whited, Matthew C; Schneider, Kristin L; Oleski, Jessica; Pagoto, Sherry L

    2011-01-01

    Emotional eating appears to contribute to weight gain, but the characteristics that make one vulnerable to emotional eating remain unclear. The present study examined whether two negative affect response styles, rumination and distraction, influenced palatable food intake following an anger mood induction in normal weight and obese adults. We hypothesized that higher rumination and lower distraction would be associated with greater vulnerability to anger-induced eating, particularly among obese individuals. Sixty-one participants (74% female, mean age=34.6) underwent neutral and anger mood inductions in counterbalanced order. Directly following each mood induction, participants were provided with 2400 kcal of highly palatable snack foods in the context of a laboratory taste test. Results revealed that distraction influenced energy intake following the mood induction for obese but not normal weight individuals. Obese participants who reported greater use of distraction strategies consumed fewer calories than those reporting less use of distraction strategies. These findings were independent of subjective hunger levels, individual differences in mood responses and trait anger, and other factors. Rumination did not account for changes in energy intake among obese or normal weight participants. Among obese individuals, the tendency to utilize fewer negative affect distraction strategies appears to be associated with vulnerability to eating in response to anger. Future research should determine whether coping skills training can reduce emotional eating tendencies.

  11. Sympathetic cardiac hyperinnervation and atrial autonomic imbalance in diet-induced obesity promote cardiac arrhythmias.

    PubMed

    McCully, Belinda H; Hasan, Wohaib; Streiff, Cole T; Houle, Jennifer C; Woodward, William R; Giraud, George D; Brooks, Virginia L; Habecker, Beth A

    2013-11-15

    Obesity increases the risk of arrhythmias and sudden cardiac death, but the mechanisms are unknown. This study tested the hypothesis that obesity-induced cardiac sympathetic outgrowth and hyperinnervation promotes the development of arrhythmic events. Male Sprague-Dawley rats (250-275 g), fed a high-fat diet (33% kcal/fat), diverged into obesity-resistant (OR) and obesity-prone (OP) groups and were compared with rats fed normal chow (13% kcal/fat; CON). In vitro experiments showed that both OR and OP rats exhibited hyperinnervation of the heart and high sympathetic outgrowth compared with CON rats, even though OR rats are not obese. Despite the hyperinnervation and outgrowth, we showed that, in vivo, OR rats were less susceptible to arrhythmic events after an intravenous epinephrine challenge compared with OP rats. On examining total and stimulus-evoked neurotransmitter levels in an ex vivo system, we demonstrate that atrial acetylcholine content and release were attenuated in OP compared with OR and CON groups. OP rats also expressed elevated atrial norepinephrine content, while norepinephrine release was suppressed. These findings suggest that the consumption of a high-fat diet, even in the absence of overt obesity, stimulates sympathetic outgrowth and hyperinnervation of the heart. However, normalized cardiac parasympathetic nervous system control may protect the heart from arrhythmic events.

  12. Obesity-induced oxidative stress, accelerated functional decline with age and increased mortality in mice

    PubMed Central

    Zhang, Yiqiang; Fischer, Kathleen E.; Soto, Vanessa; Liu, Yuhong; Sosnowska, Danuta; Richardson, Arlan; Salmon, Adam B.

    2015-01-01

    Obesity is a serious chronic disease that increases the risk of numerous co-morbidities including metabolic syndrome, cardiovascular disease and cancer as well as increases risk of mortality leading some to suggest this represents accelerated aging. Obesity is associated with significant increases in oxidative stress in vivo and, despite the well-explored relationship between oxidative stress and aging, the role this plays in the increased mortality of obese subjects remains an unanswered question. Here, we addressed this by undertaking a comprehensive, longitudinal study of a group of high fat-fed obese mice and assessed both their changes in oxidative stress and in their performance in physiological assays known to decline with aging. In female C57BL/6J mice fed a high-fat diet starting in adulthood, mortality was significantly increased in high fat-fed mice as was oxidative damage in vivo. High fat-feeding significantly accelerated the decline in performance in several assays, including activity, gait, and rotarod. However, we also found that obesity had little effect on other markers and actually improved performance in grip strength, a marker of muscular function. Together, this first comprehensive assessment of longitudinal functional changes in high fat-fed mice suggests that obesity may induce segmental acceleration of some of the aging process. PMID:25558793

  13. Adrenomedullin promotes angiogenesis in epithelial ovarian cancer through upregulating hypoxia-inducible factor-1α and vascular endothelial growth factor

    PubMed Central

    Zhang, Yi; Xu, Yang; Ma, Jian; Pang, Xiaoyan; Dong, Mei

    2017-01-01

    Adrenomedullin (ADM) is a multi-functional peptide related to many kinds of tumors. This study was aimed to investigate the role of ADM on angiogenesis in epithelial ovarian cancer (EOC) and its possible mechanism. The expressions of ADM, vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1α (HIF-1α) and CD34 were examined by immunohistochemistry staining. The relationship among ADM, HIF-1α, VEGF and micro-vessel density (MVD) was assessed in 56 EOC tissues. CAOV3 cells were stably transfected with pcDNA-ADM (plasmid overexpressing ADM gene) or pRNA-shADM (small interfering RNA for ADM gene). Real-time PCR and western blot analysis were performed to detect the expressions of HIF-1α and VEGF. The MTT, transwell migration assay and in vitro tube formation analysis were used to evaluate the proliferation, migration, and tube formation ability of human umbilical vein endothelial cells (HUVECs) which were pretreated with ADM or ADM receptor antagonist ADM22-52. Our findings showed that ADM expression was positively correlated with the expressions of HIF-1α, VEGF or MVD in EOC. ADM upregulated expression of HIF-1α and VEGF in CAOV3 cells. ADM promoted HUVECs proliferation, migration and tube formation. In conclusion, ADM was an upstream molecule of HIF-1α/VEGF and it promoted angiogenesis through upregulating HIF-1α/VEGF in EOC. PMID:28091613

  14. Sesamin induces melanogenesis by microphthalmia-associated transcription factor and tyrosinase up-regulation via cAMP signaling pathway.

    PubMed

    Jiang, Zequn; Li, Shasha; Liu, Yunyi; Deng, Pengyi; Huang, Jianguo; He, Guangyuan

    2011-10-01

    In this study, we confirmed that sesamin, an active lignan isolated from sesame seed and oil, is a novel skin-tanning compound. The melanin content and tyrosinase activity were increased by sesamin in a dose-dependent manner in B16 melanoma cells. The mRNA and protein levels of tyrosinase were also enhanced after the treatment with sesamin. Western blot analysis revealed that sesamin induced and sustained up-regulation of microphthalmia-associated transcription factor (MITF). Sesamin could activate cAMP response element (CRE) binding protein (CREB), but it had no effect on the phosphorylation of p38 mitogen-activated protein kinase (MAPK) or Akt. Moreover, sesamin activated protein kinase A (PKA) via a cAMP-dependent pathway. Consistent with these results, sesamin-mediated increase of melanin synthesis was reduced significantly by H-89, a PKA inhibitor, but not by SB203580, a p38 MAPK inhibitor or by LY294002, a phosphatidylinositol-3-kinase (PI3K) inhibitor. Sesamin-mediated phosphorylation of CREB and induction of MITF and tyrosinase expression were also inhibited by H-89. These findings indicated that sesamin could stimulate melanogenesis in B16 cells via the up-regulation of MITF and tyrosinase, which was, in turn, due to the activation of cAMP signaling.

  15. Hesperidin upregulates heme oxygenase-1 to attenuate hydrogen peroxide-induced cell damage in hepatic L02 cells.

    PubMed

    Chen, Ming-Cang; Ye, Yi-Yi; Ji, Guang; Liu, Jian-Wen

    2010-03-24

    Hesperidin, a naturally occurring flavonoid presents in fruits and vegetables, has been reported to exert a wide range of pharmacological effects that include antioxidant, anti-inflammatory, antihypercholesterolemic, and anticarcinogenic actions. However, the cytoprotection and mechanism of hesperidin to neutralize oxidative stress in human hepatic L02 cells remain unclear. In this work, we assessed the capability of hesperidin to attenuate hydrogen peroxide (H(2)O(2))-induced cell damage by augmenting the cellular antioxidant defense. Real-time quantitative polymerase chain reaction, Western blot, and enzyme activity assay demonstrated that hesperidin upregulated heme oxygenase-1 (HO-1) expression to protect hepatocytes against oxidative stress. In addition, hesperidin also promoted nuclear translocation of nuclear factor erythroid 2-related factor (Nrf2). What's more, hesperidin exhibited activation of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Besides, ERK1/2 inhibitor significantly inhibited hesperidin-mediated HO-1 upregulation and Nrf2 nuclear translocation. Taken together, the above findings suggested that hesperidin augmented cellular antioxidant defense capacity through the induction of HO-1 via ERK/Nrf2 signaling. Therefore, hesperidin has potential as a therapeutic agent in the treatment of oxidative stress-related hepatocyte injury and liver dysfunctions.

  16. Nicotine Induced Murine Spermatozoa Apoptosis via Up-Regulation of Deubiquitinated RIP1 by Trim27 Promoter Hypomethylation.

    PubMed

    Nie, Dongsheng; Zhang, Dong; Dai, Jingbo; Zhang, Meixing; Zhao, Xianglong; Xu, Wangjie; Chen, Zhong; Wang, Lianyun; Wang, Zhaoxia; Qiao, Zhongdong

    2016-02-01

    Nicotine significantly promoted apoptosis in stages I, VII, VIII, and XI spermatogonia, stages I, VII, VIII, X, and XI spermatocytes, and stages I-V, VII, and VIII elongating spermatids. To explore the underlying molecular mechanisms, sperm mRNA next-generation sequencing of nicotine-treated mice was conducted. Out of the 86 genes related to apoptosis, Tnf (tumor necrosis factor alpha) was screened to be the most significant varied transcript, and the Onto-pathway analysis indicated that the TNF apoptotic pathway was especially activated by nicotine exposure. The TNF pathway was further studied at the gene and protein levels. The results showed that RIP1, the key component in the TNF apoptotic pathway, was up-expressed in its deubiquitinated form in nicotine-treated mice testis. TRIM27, an E3 ubiquitin ligase that activated TNF apoptotic pathway through up-regulating deubiquitinated RIP1, was also overexpressed in nicotine-treated spermatocytes; moreover, four consecutive CpG sites near the Trim27 transcription start site were less frequently methylated. Finally, in vitro experiments of Trim27 overexpression and RNA interference in GC-1 spermatogonial cells confirmed that the RIP1 deubiquitination and TRIM27 hyopmethylation were both positively correlated with spermatocyte apoptosis. In summary, our study suggests that nicotine may induce murine spermatozoal apoptosis via the TNF apoptotic pathway through up-regulation of deubiquitinated RIP1 by Trim27 promoter hypomethylation.

  17. MicroRNAs up-regulated by CagA of Helicobacter pylori induce intestinal metaplasia of gastric epithelial cells.

    PubMed

    Zhu, Yongliang; Jiang, Qiaoli; Lou, Xiaojun; Ji, Xiaowei; Wen, Zhenzhen; Wu, Jia; Tao, Haiying; Jiang, Tingting; He, Wei; Wang, Caihua; Du, Qin; Zheng, Shu; Mao, Jianshan; Huang, Jian

    2012-01-01

    CagA of Helicobacter pylori is a bacterium-derived oncogenic protein closely associated with the development of gastric cancers. MicroRNAs (miRNAs) are a class of widespread non-coding RNAs, many of which are involved in cell growth, cell differentiation and tumorigenesis. The relationship between CagA protein and miRNAs is unclear. Using mammalian miRNA profile microarrays, we found that miRNA-584 and miRNA-1290 expression was up-regulated in CagA-transformed cells, miRNA-1290 was up-regulated in an Erk1/2-dependent manner, and miRNA-584 was activated by NF-κB. miRNA-584 sustained Erk1/2 activities through inhibition of PPP2a activities, and miRNA-1290 activated NF-κB by knockdown of NKRF. Foxa1 was revealed to be an important target of miRNA-584 and miRNA-1290. Knockdown of Foxa1 promoted the epithelial-mesenchymal transition significantly. Overexpression of miRNA-584 and miRNA-1290 induced intestinal metaplasia of gastric epithelial cells in knock-in mice. These results indicate that miRNA-584 and miRNA-1290 interfere with cell differentiation and remodel the tissues. Thus, the miRNA pathway is a new pathogenic mechanism of CagA.

  18. SERMs attenuate estrogen-induced malignant transformation of human mammary epithelial cells by upregulating detoxification of oxidative metabolites

    PubMed Central

    Madhubhani, L.P.; Hemachandra, P.; Patel, Hitisha; Esala, R.; Chandrasena, P.; Choi, Jaewoo; Piyankarage, Sujeewa C.; Wang, Shuai; Wang, Yijin; Thayer, Emily; Scism, Rob; Michalsen, Bradley T.; Xiong, Rui; Siklos, Marton; Bolton, Judy L.; Thatcher, Gregory R.J.

    2014-01-01

    The risk of developing hormone-dependent cancers with long-term exposure to estrogens is attributed both to proliferative, hormonal actions at the estrogen receptor (ER), and chemical carcinogenesis elicited by genotoxic, oxidative estrogen metabolites. Non-tumorigenic MCF-10A human breast epithelial cells are classified as ER(−) and undergo estrogen-induced malignant transformation. Selective estrogen receptor modulators (SERMs), in use for breast cancer chemoprevention and for post-menopausal osteoporosis, were observed to inhibit malignant transformation, as measured by anchorage-independent colony growth. This chemopreventive activity was observed to correlate with reduced levels of oxidative estrogen metabolites, cellular ROS, and DNA oxidation. The ability of raloxifene, desmethylarzoxifene (DMA), and bazedoxifene to inhibit this chemical carcinogenesis pathway was not shared by 4-hydroxytamoxifen. Regulation of Phase 2 rather than Phase 1 metabolic enzymes was implicated mechanistically: raloxifene and DMA were observed to upregulate sulfotransferase (SULT 1E1) and glucuronidase (UGT 1A1). The results support upregulation of Phase 2 metabolism in detoxification of catechol estrogen metabolites leading to attenuated ROS formation as a mechanism for inhibition of malignant transformation by a subset of clinically important SERMs. PMID:24598415

  19. Diet-induced obesity reprograms the inflammatory response of the murine lung to inhaled endotoxin.

    PubMed

    Tilton, Susan C; Waters, Katrina M; Karin, Norman J; Webb-Robertson, Bobbie-Jo M; Zangar, Richard C; Lee, K Monica; Bigelow, Diana J; Pounds, Joel G; Corley, Richard A

    2013-03-01

    The co-occurrence of environmental factors is common in complex human diseases and, as such, understanding the molecular responses involved is essential to determine risk and susceptibility to disease. We have investigated the key biological pathways that define susceptibility for pulmonary infection during obesity in diet-induced obese (DIO) and regular weight (RW) C57BL/6 mice exposed to inhaled lipopolysaccharide (LPS). LPS induced a strong inflammatory response in all mice as indicated by elevated cell counts of macrophages and neutrophils and levels of proinflammatory cytokines (MDC, MIP-1γ, IL-12, RANTES) in the bronchoalveolar lavage fluid. Additionally, DIO mice exhibited 50% greater macrophage cell counts, but decreased levels of the cytokines, IL-6, TARC, TNF-α, and VEGF relative to RW mice. Microarray analysis of lung tissue showed over half of the LPS-induced expression in DIO mice consisted of genes unique for obese mice, suggesting that obesity reprograms how the lung responds to subsequent insult. In particular, we found that obese animals exposed to LPS have gene signatures showing increased inflammatory and oxidative stress response and decreased antioxidant capacity compared with RW. Because signaling pathways for these responses can be common to various sources of environmentally induced lung damage, we further identified biomarkers that are indicative of specific toxicant exposure by comparing gene signatures after LPS exposure to those from a parallel study with cigarette smoke. These data show obesity may increase sensitivity to further insult and that co-occurrence of environmental stressors result in complex biosignatures that are not predicted from analysis of individual exposures.

  20. Heart energy metabolism impairment in Western-diet induced obese mice.

    PubMed

    Neves, Fabiana A; Cortez, Erika; Bernardo, Amélia F; Mattos, Ana B M; Vieira, Anatalia K; Malafaia, Tayanne de O; Thole, Alessandra A; Rodrigues-Cunha, Alessandra C de S; Garcia-Souza, Erica P; Sichieri, Rosely; Moura, Anibal S

    2014-01-01

    Nutritional transition has contributed to growing obesity, mainly by changing eating habits of the population. The mechanisms by which diet-induced obesity leads to cardiac injury are not completely understood, but it is known that obesity is associated to impaired cardiac function and energy metabolism, increasing morbidity and mortality. Therefore, our study aimed to investigate the mechanisms underlying cardiac metabolism impairment related to Western diet-induced obesity. After weaning, male Swiss mice were fed a Western diet for 16 weeks in order to induce obesity. After this period, the content of proteins involved in heart energy metabolism GLUT1, cytosolic lysate and plasma membrane GLUT4, AMPK, pAMPK, IRβ, IRS-1, PGC-1α, CPT1 and UCP2 was evaluated. Also, the oxidative phosphorylation of myocardial fibers was measured by high-resolution respirometry. Mice in the Western diet group (WG) presented altered biometric parameters compared to those in control group, including higher body weight, increased myocardial lipid deposition and glucose intolerance, which demonstrate the obesogenic role of Western diet. WG presented increased CPT1 and UCP2 contents and decreased IRS-1, plasma membrane GLUT4 and PGC-1α contents. In addition, WG presented cardiac mitochondrial dysfunction and reduced biogenesis, demonstrating a lower capacity of carbohydrates and fatty acid oxidation and also decreased coupling between oxidative phosphorylation and adenosine triphosphate synthesis. Cardiac metabolism impairment related to Western diet-induced obesity is probably due to damaged myocardial oxidative capacity, reduced mitochondrial biogenesis and mitochondria uncoupling, which compromise the bioenergetic metabolism of heart.

  1. Diet-Induced Obesity Reprograms the Inflammatory Response of the Murine Lung to Inhaled Endotoxin

    SciTech Connect

    Tilton, Susan C.; Waters, Katrina M.; Karin, Norman J.; Webb-Robertson, Bobbie-Jo M.; Zangar, Richard C.; Lee, Monika K.; Bigelow, Diana J.; Pounds, Joel G.; Corley, Richard A.

    2013-03-01

    The co-occurrence of environmental factors is common in complex human diseases and, as such, understanding the molecular responses involved is essential to determine risk and susceptibility to disease. We have investigated the key biological pathways that define susceptibility for pulmonary infection during obesity in diet-induced obese (DIO) and regular weight (RW) C57BL/6 mice exposed to inhaled lipopolysaccharide (LPS). LPS induced a strong inflammatory response in all mice as indicated by elevated cell counts of macrophages and neutrophils and levels of proinflammatory cytokines (MDC, MIP-1γ, IL-12, RANTES) in the bronchoalveolar lavage fluid. Additionally, DIO mice exhibited 50% greater macrophage cell counts, but decreased levels of the cytokines, IL-6, TARC, TNF-α, and VEGF relative to RW mice. Microarray analysis of lung tissue showed over half of the LPS-induced expression in DIO mice consisted of genes unique for obese mice, suggesting that obesity reprograms how the lung responds to subsequent insult. In particular, we found that obese animals exposed to LPS have gene signatures showing increased inflammatory and oxidative stress response and decreased antioxidant capacity compared with RW. Because signaling pathways for these responses can be common to various sources of environmentally induced lung damage, we further identified biomarkers that are indicative of specific toxicant exposure by comparing gene signatures after LPS exposure to those from a parallel study with cigarette smoke. These data show obesity may increase sensitivity to further insult and that co-occurrence of environmental stressors result in complex biosignatures that are not predicted from analysis of individual exposures.

  2. Altering sphingolipid composition with aging induces contractile dysfunction of gastric smooth muscle via K(Ca) 1.1 upregulation.

    PubMed

    Choi, Shinkyu; Kim, Ji Aee; Kim, Tae Hun; Li, Hai-Yan; Shin, Kyong-Oh; Lee, Yong-Moon; Oh, Seikwan; Pewzner-Jung, Yael; Futerman, Anthony H; Suh, Suk Hyo

    2015-12-01

    K(Ca) 1.1 regulates smooth muscle contractility by modulating membrane potential, and age-associated changes in K(Ca) 1.1 expression may contribute to the development of motility disorders of the gastrointestinal tract. Sphingolipids (SLs) are important structural components of cellular membranes whose altered composition may affect K(Ca) 1.1 expression. Thus, in this study, we examined whether altered SL composition due to aging may affect the contractility of gastric smooth muscle (GSM). We studied changes in ceramide synthases (CerS) and SL levels in the GSM of mice of varying ages and compared them with those in young CerS2-null mice. The levels of C16- and C18-ceramides, sphinganine, sphingosine, and sphingosine 1-phosphate were increased, and levels of C22, C24:1 and C24 ceramides were decreased in the GSM of both aged wild-type and young CerS2-null mice. The altered SL composition upregulated K(Ca) 1.1 and increased K(Ca) 1.1 currents, while no change was observed in K(Ca) 1.1 channel activity. The upregulation of KC a 1.1 impaired intracellular Ca²⁺mobilization and decreased phosphorylated myosin light chain levels, causing GSM contractile dysfunction. Additionally, phosphoinositide 3-kinase, protein kinase Cζ , c-Jun N-terminal kinases, and nuclear factor kappa-B were found to be involved in K(Ca) 1.1 upregulation. Our findings suggest that age-associated changes in SL composition or CerS2 ablation upregulate K(Ca) 1.1 via the phosphoinositide 3-kinase/protein kinase Cζ /c-Jun N-terminal kinases/nuclear factor kappa-B-mediated pathway and impair Ca²⁺ mobilization, which thereby induces the contractile dysfunction of GSM. CerS2-null mice exhibited similar effects to aged wild-type mice; therefore, CerS2-null mouse models may be utilized for investigating the pathogenesis of aging-associated motility disorders.

  3. Role of the vagus nerve in the development and treatment of diet-induced obesity.

    PubMed

    de Lartigue, Guillaume

    2016-10-15

    This review highlights evidence for a role of the vagus nerve in the development of obesity and how targeting the vagus nerve with neuromodulation or pharmacology can be used as a therapeutic treatment of obesity. The vagus nerve innervating the gut plays an important role in controlling metabolism. It communicates peripheral information about the volume and type of nutrients between the gut and the brain. Depending on the nutritional status, vagal afferent neurons express two different neurochemical phenotypes that can inhibit or stimulate food intake. Chronic ingestion of calorie-rich diets reduces sensitivity of vagal afferent neurons to peripheral signals and their constitutive expression of orexigenic receptors and neuropeptides. This disruption of vagal afferent signalling is sufficient to drive hyperphagia and obesity. Furthermore neuromodulation of the vagus nerve can be used in the treatment of obesity. Although the mechanisms are poorly understood, vagal nerve stimulation prevents weight gain in response to a high-fat diet. In small clinical studies, in patients with depression or epilepsy, vagal nerve stimulation has been demonstrated to promote weight loss. Vagal blockade, which inhibits the vagus nerve, results in significant weight loss. Vagal blockade is proposed to inhibit aberrant orexigenic signals arising in obesity as a putative mechanism of vagal blockade-induced weight loss. Approaches and molecular targets to develop future pharmacotherapy targeted to the vagus nerve for the treatment of obesity are proposed. In conclusion there is strong evidence that the vagus nerve is involved in the development of obesity and it is proving to be an attractive target for the treatment of obesity.

  4. Everolimus exhibits anti-tumorigenic activity in obesity-induced ovarian cancer

    PubMed Central

    Guo, Hui; Zhong, Yan; Jackson, Amanda L.; Clark, Leslie H.; Kilgore, Josh; Zhang, Lu; Han, Jianjun; Sheng, Xiugui; Gilliam, Timothy P.; Gehrig, Paola A.; Zhou, Chunxiao; Bae, Victoria L.

    2016-01-01

    Everolimus inhibits mTOR kinase activity and its downstream targets by acting on mTORC1 and has anti-tumorigenic activity in ovarian cancer. Clinical and epidemiologic data find that obesity is associated with worse outcomes in ovarian cancer. In addition, obesity leads to hyperactivation of the mTOR pathway in epithelial tissues, suggesting that mTOR inhibitors may be a logical choice for treatment in obesity-driven cancers. However, it remains unclear if obesity impacts the effect of everolimus on tumor growth in ovarian cancer. The present study was aimed at evaluating the effects of everolimus on cytotoxicity, cell metabolism, apoptosis, cell cycle, cell stress and invasion in human ovarian cancer cells. A genetically engineered mouse model of serous ovarian cancer fed a high fat diet or low fat diet allowed further investigation into the inter-relationship between everolimus and obesity in vivo. Everolimus significantly inhibited cellular proliferation, induced cell cycle G1 arrest and apoptosis, reduced invasion and caused cellular stress via inhibition of mTOR pathways in vitro. Hypoglycemic conditions enhanced the sensitivity of cells to everolimus through the disruption of glycolysis. Moreover, everolimus was found to inhibit ovarian tumor growth in both obese and lean mice. This reduction coincided with a decrease in expression of Ki-67 and phosphorylated-S6, as well as an increase in cleaved caspase 3 and phosphorylated-AKT. Metabolite profiling revealed that everolimus was able to alter tumor metabolism through different metabolic pathways in the obese and lean mice. Our findings support that everolimus may be a promising therapeutic agent for obesity-driven ovarian cancers. PMID:26959121

  5. Flow-induced remodeling in resistance arteries from obese Zucker rats is associated with endothelial dysfunction.

    PubMed

    Bouvet, Céline; Belin de Chantemèle, Eric; Guihot, Anne-Laure; Vessières, Emilie; Bocquet, Arnaud; Dumont, Odile; Jardel, Alain; Loufrani, Laurent; Moreau, Pierre; Henrion, Daniel

    2007-07-01

    Chronic increases in blood flow increase arterial diameter and NO-dependent dilation in resistance arteries. Because endothelial dysfunction accompanies metabolic syndrome, we hypothesized that flow-mediated remodeling might be impaired in obese rat resistance arteries. Obese and lean Zucker rat mesenteric resistance arteries were exposed to chronic flow increases through arterial ligation in vivo: arteries exposed to high flow were compared with normal flow arteries. Diameter was measured in vitro in cannulated arteries using pressure arteriography. After 7 days, outward remodeling (diameter increased from 346+/-9 to 412+/-11 mum at 100 mm Hg) occurred in lean high-flow arteries. Endothelium-dependent tone was reduced in high-flow arteries from obese rats by contrast with lean animals. On the other hand, diameter enlargement occurred similarly in the 2 strains. The involvement of NO in endothelium-dependent dilation (evidenced by NO blockade) and endothelial NO synthase phosphorylation was smaller in obese than in lean rats. Superoxide anion and reduced nicotinamide-adenine dinucleotide phosphate oxidase subunit expression (p67phox and gp91phox) increased in obese rats and were higher in high-flow than in control arteries. Acute Tempol (a catalase mimetic), catalase plus superoxide dismutase, and l-arginine plus tetrahydrobiopterin restored endothelium-dependent dilation in obese rat normal and high-flow arteries to the level found in lean control arteries. Thus, flow-induced remodeling in obese resistance arteries was associated with a reduced endothelium-mediated dilation because of a decreased NO bioavailability and an excessive superoxide production. This dysfunction might have negative consequences in ischemic diseases in patients with obesity or metabolic syndrome.

  6. Homocysteine induces cardiac hypertrophy by up-regulating ATP7a expression

    PubMed Central

    Cao, Zhanwei; Zhang, Yanzhou; Sun, Tongwen; Zhang, Shuguang; Yu, Weiya; Zhu, Jie

    2015-01-01

    Aims: The aim of the study is to investigate the molecular mechanism by which homocysteine (Hcy) induces cardiac hypertrophy. Methods: Primary cardiomyocytes were obtained from baby Sprague-Dawley rats within 3 days after birth. Flow cytometry was used to measure cell sizes. Quantitative real-time polymerase chain reaction was performed to measure the expression of β-myosin heavy chain and atrial natriuretic peptide genes. Western blotting assay was employed to determine ATP7a protein expression. Cytochrome C oxidase (COX) activity test was used to evaluate the activity of COX. Atomic absorption spectroscopy was performed to determine copper content. siRNAs were used to target-silence the expression of ATP7a. Results: Hcy induced cardiac hypertrophy and increased the expression of cardiac hypertrophy-related genes. ATP7a was a key factor in cardiac hypertrophy induced by Hcy. Reduced ATP7a expression inhibited cardiac hypertrophy induced by Hcy. Elevated ATP7a expression induced by Hcy inhibited COX activity. Enhanced ATP7a expression inhibited COX activity by lowering intracellular copper content. Conclusions: Hcy elevates ATP7a protein expression, reduces copper content, and lowers COX activity, finally leading to cardiac hypertrophy. PMID:26722473

  7. Hyaluronic acid prevents immunosuppressive drug-induced ovarian damage via up-regulating PGRMC1 expression

    PubMed Central

    Zhao, Guangfeng; Yan, Guijun; Cheng, Jie; Zhou, Xue; Fang, Ting; Sun, Haixiang; Hou, Yayi; Hu, Yali

    2015-01-01

    Chemotherapy treatment in women can frequently cause damage to the ovaries, which may lead to primary ovarian insufficiency (POI). In this study, we assessed the preventative effects of hyaluronic acid (HA) in immunosuppressive drug-induced POI-like rat models and investigated the possible mechanisms. We found that HA, which was reduced in primary and immunosuppressant-induced POI patients, could protect the immunosuppressant-induced damage to granulosa cells (GCs) in vitro. Then we found that HA blocked the tripterygium glycosides (TG) induced POI-like presentations in rats, including delayed or irregular estrous cycles, reduced 17 beta-estradiol(E2) concentration, decreased number of follicles, destruction of follicle structure, and damage of reproductive ability. Furthermore, we investigated the mechanisms of HA prevention effects on POI, which was associated with promotion of GC proliferation and PGRMC1 expression. In conclusion, HA prevents chemotherapy-induced ovarian damage by promoting PGRMC1 in GCs. This study may provide a new strategy for prevention and treatment of POI. PMID:25558795

  8. Prohibitin-induced, obesity-associated insulin resistance and accompanying low-grade inflammation causes NASH and HCC.

    PubMed

    Ande, Sudharsana R; Nguyen, K Hoa; Grégoire Nyomba, B L; Mishra, Suresh

    2016-03-23

    Obesity increases the risk for nonalcoholic steatohepatitis (NASH) and hepatocarcinogenesis. However, the underlying mechanisms involved in the disease process remain unclear. Recently, we have developed a transgenic obese mouse model (Mito-Ob) by prohibitin mediated mitochondrial remodeling in adipocytes. The Mito-Ob mice develop obesity in a sex-neutral manner, but obesity-associated adipose inflammation and metabolic dysregulation in a male sex-specific manner. Here we report that with aging, the male Mito-Ob mice spontaneously develop obesity-linked NASH and hepatocellular carcinoma (HCC). In contrast, the female Mito-Ob mice maintained normal glucose and insulin levels and did not develop NASH and HCC. The anti-inflammatory peptide ghrelin was significantly upregulated in the female mice and down regulated in the male mice compared with respective control mice. In addition, a reduction in the markers of mitochondrial content and function was found in the liver of male Mito-Ob mice with NASH/HCC development. We found that ERK1/2 signaling was significantly upregulated whereas STAT3 signaling was significantly down regulated in the tumors from Mito-Ob mice. These data provide a proof-of-concept that the metabolic and inflammatory status of the adipose tissue and their interplay at the systemic and hepatic level play a central role in the pathogenesis of obesity-linked NASH and HCC.

  9. Chronic rhein treatment improves recognition memory in high-fat diet-induced obese male mice.

    PubMed

    Wang, Sen; Huang, Xu-Feng; Zhang, Peng; Wang, Hongqin; Zhang, Qingsheng; Yu, Shijia; Yu, Yinghua

    2016-10-01

    High-fat (HF) diet modulates gut microbiota and increases plasma concentration of lipopolysaccharide (LPS) which is associated with obesity and its related low-grade inflammation and cognitive decline. Rhein is the main ingredient of the rhubarb plant which has been used as an anti-inflammatory agent for several millennia. However, the potential effects of rhein against HF diet-induced obesity and its associated alteration of gut microbiota, inflammation and cognitive decline have not been studied. In this study, C57BL/6J male mice were fed an HF diet for 8 weeks to induce obesity, and then treated with oral rhein (120 mg/kg body weight/day in HF diet) for a further 6 weeks. Chronic rhein treatment prevented the HF diet-induced recognition memory impairment assessed by the novel object recognition test, neuroinflammation and brain-derived neurotrophic factor (BDNF) deficits in the perirhinal cortex. Furthermore, rhein inhibited the HF diet-induced increased plasma LPS level and the proinflammatory macrophage accumulation in the colon and alteration of microbiota, including decreasing Bacteroides-Prevotella spp. and Desulfovibrios spp. DNA and increasing Bifidobacterium spp. and Lactobacillus spp. DNA. Moreover, rhein also reduced body weight and improved glucose tolerance in HF diet-induced obese mice. In conclusion, rhein improved recognition memory and prevented obesity in mice on a chronic HF diet. These beneficial effects occur via the modulation of microbiota, hypoendotoxinemia, inhibition of macrophage accumulation, anti-neuroinflammation and the improvement of BDNF expression. Therefore, supplementation with rhein-enriched food or herbal medicine could be beneficial as a preventive strategy for chronic HF diet-induced cognitive decline, microbiota alteration and neuroinflammation.

  10. Obesity induced by cafeteria feeding and pregnancy outcome in the rat.

    PubMed

    Akyol, Asli; Langley-Evans, Simon C; McMullen, Sarah

    2009-12-01

    Obesity during pregnancy has major consequences for maternal and neonatal health, but the long-term effects on the offspring are less clear. It is not known whether the effects observed in animal models are a result of maternal obesity per se or of the high-fat diets used to induce obesity. This investigation aimed to develop a model for the evaluation of the independent effects of cafeteria feeding and maternal obesity, considering their impact on plasma volume expansion, circulating metabolites, and fetal and placental growth. Wistar rats were fed a control or cafeteria diet from weaning. After 8 weeks, all animals were mated and half of the animals within each group were crossed-over to the alternative diet. This generated four treatment groups, differing in their pre-gestational and gestational diets. Half of the animals were culled at day 5 of gestation and the remainder at day 20. Maternal body composition, blood volume and circulating glucose, TAG and cholesterol were determined. Cafeteria feeding was effective in inducing obesity, as demonstrated by increased fat depot weights and total body fat, without impacting upon reproductive success or circulating lipid concentrations. The study successfully demonstrated that there were differential effects of maternal body fatness and diet upon fetal and placental growth, with pre-gestational obesity leading to lower fetal weight at day 20 of gestation (P < 0.001). The model will provide a useful vehicle for the investigation of the complex interactions between dietary- and obesity-related factors during pregnancy in their effects on fetal development and postnatal metabolic function.

  11. Cysteine induces longitudinal bone growth in mice by upregulating IGF-I.

    PubMed

    Moon, Phil-Dong; Kim, Min-Ho; Oh, Hyun-A; Nam, Sun-Young; Han, Na-Ra; Jeong, Hyun-Ja; Kim, Hyung-Min

    2015-08-01

    Cysteine (Cys) is known to exert various effects, such as antioxidant, antipancreatitic and antidiabetic effects. However, the effects of Cys on longitudinal bone growth have not been elucidate to date. Thus, the aim of the present study was to evaluate the effects of Cys on bone growth. Growth-plate thickness and bone parameters, such as bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), connectivity density (Conn.D) and total porosity were analyzed by means of micro-computed tomography (μCT). The levels of serum insulin-like growth factor-I (IGF-I) were measured by enzyme-linked immunosorbent assay (ELISA). Hepatic IGF-I mRNA expression was analyzed by quantitative polymerase chain reaction (qPCR). The phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 5 (STAT5) was investigated by western blot analysis. Our results revealed that Cys increased IGF-I mRNA expression in HepG2 cells. The thickness of the growth plates was increased following treatment with Cys. Moreover, BV/TV, Tb.Th, TbN, Conn.D and total porosity were improved following treatment with Cys. Hepatic IGF-I mRNA expression and serum IGF-I levels were increased by Cys. The levels of phosphorylated JAK2 and STAT5 were elevated by Cys. The findings of our study indicate that Cys increases the thickness of growth plates through the upregulation of IGF-I, which results from the phosphorylation of JAK2-STAT5. Thus, our data suggest that Cys may have potential for use as a growth-promoting agent.

  12. Upregulation of bradykinin receptors is implicated in the pain associated with caerulein-induced acute pancreatitis.

    PubMed

    Takemura, Yoshinori; Furuta, Sadayoshi; Hirayama, Shigeto; Miyashita, Kazuhiko; Imai, Satoshi; Narita, Michiko; Kuzumaki, Naoko; Tsukiyama, Yoshi; Yamazaki, Mitsuaki; Suzuki, Tsutomu; Narita, Minoru

    2011-07-01

    Although the way for pain management associated with acute pancreatitis has been searched for, there are not enough medications available for it. The aim of the present study was to investigate the role of bradykinin (BK) in pain related to acute pancreatitis. After repeated injections of caerulein (50 μg/kg and 6 times), mice showed edema in the pancreas, and blood concentrations of pancreatic enzymes (amylase and lipase) were clearly elevated. A histopathological study demonstrated that caerulein caused tissue damage characterized by edema, acinar cell necrosis, interstitial hemorrhage, and inflammatory cell infiltrates. Furthermore, the mRNA levels of interleukin-1β and monocyte chemotactic protein (MCP)-1 were significantly increased in the pancreas of caerulein-treated mice. The sensitivity of abdominal organs as measured by abdominal balloon distension was enhanced in caerulein-injected mice, suggesting that caerulein caused pancreatic hyperalgesia. Moreover, repeated treatment with caerulein resulted in cutaneous tactile allodynia of the upper abdominal region as demonstrated by the use of von Frey filaments, indicating that caerulein-treated mice exhibited referred pain. Under this condition, the mRNA levels of bradykinin B1 receptor (BKB1R) and bradykinin B2 receptor (BKB2R) were significantly increased in the dorsal root ganglion (DRG). Finally, we found that des-Arg⁹-(Leu⁸)-bradykinin (BKB1R antagonist) and HOE-140 (BKB2R antagonist) attenuated the acute pancreatitis pain-like state in caerulein-treated mice. These findings suggest that the upregulation of BK receptors in the DRG may, at least in part, contribute to the development of the acute pancreatitis pain-like state in mice.

  13. Resveratrol inhibits IL-6-induced ovarian cancer cell migration through epigenetic up-regulation of autophagy.

    PubMed

    Ferraresi, Alessandra; Phadngam, Suratchanee; Morani, Federica; Galetto, Alessandra; Alabiso, Oscar; Chiorino, Giovanna; Isidoro, Ciro

    2017-03-01

    Interleukin-6 (IL-6), a pro-inflammatory cytokine released by cancer-associated fibroblasts, has been linked to the invasive and metastatic behavior of ovarian cancer cells. Resveratrol is a naturally occurring polyphenol with the potential to inhibit cancer cell migration. Here we show that Resveratrol and IL-6 affect in an opposite manner the expression of RNA messengers and of microRNAs involved in cell locomotion and extracellular matrix remodeling associated with the invasive properties of ovarian cancer cells. Among the several potential candidates responsible for the anti-invasive effect promoted by Resveratrol, here we focused our attention on ARH-I (DIRAS3), that encodes a Ras homolog GTPase of 26-kDa. This protein is known to inhibit cell motility, and it has been shown to regulate autophagy by interacting with BECLIN 1. IL-6 down-regulated the expression of ARH-I and inhibited the formation of LC3-positive autophagic vacuoles, while promoting cell migration. On opposite, Resveratrol could counteract the IL-6 induction of cell migration in ovarian cancer cells through induction of autophagy in the cells at the migration front, which was paralleled by up-regulation of ARH-I and down-regulation of STAT3 expression. Spautin 1-mediated disruption of BECLIN 1-dependent autophagy abrogated the effects of Resveratrol, while promoting cell migration. The present data indicate that Resveratrol elicits its anti-tumor effect through epigenetic mechanisms and support its inclusion in the chemotherapy regimen for highly aggressive ovarian cancers. © 2016 Wiley Periodicals, Inc.

  14. Capsaicin attenuates LPS-induced inflammatory cytokine production by upregulation of LXRα.

    PubMed

    Tang, Jing; Luo, Kang; Li, Yan; Chen, Quan; Tang, Dan; Wang, Deming; Xiao, Ji

    2015-09-01

    Here, we investigated the role of LXRα in capsaicin mediated anti-inflammatory effects. Results revealed that capsaicin inhibits LPS-induced IL-1β, IL-6 and TNF-α production in a time- and dose-dependent manner. Moreover, capsaicin increases LXRα expression through PPARγ pathway. Inhibition of LXRα activation by siRNA diminished the inhibitory action of capsaicin on LPS-induced IL-1β, IL-6 and TNF-α production. Additionally, LXRα siRNA abrogated the inhibitory action of capsaicin on p65 NF-κB protein expression. Thus, we propose that the anti-inflammatory effects of capsaicin are LXRα dependent, and LXRα may potentially link the capsaicin mediated PPARγ activation and NF-κB inhibition in LPS-induced inflammatory response.

  15. SN79, a sigma receptor ligand, blocks methamphetamine-induced microglial activation and cytokine upregulation.

    PubMed

    Robson, Matthew J; Turner, Ryan C; Naser, Zachary J; McCurdy, Christopher R; Huber, Jason D; Matsumoto, Rae R

    2013-09-01

    Methamphetamine (METH) abuse is associated with several negative side effects including neurotoxicity in specific brain regions such as the striatum. The precise molecular mechanisms by which METH usage results in neurotoxicity remain to be fully elucidated, with recent evidence implicating the importance of microglial activation and neuroinflammation in damaged brain regions. METH interacts with sigma receptors which are found in glial cells in addition to neurons. Moreover, sigma receptor antagonists have been shown to block METH-induced neurotoxicity in rodents although the cellular mechanisms underlying their neuroprotection remain unknown. The purpose of the current study was to determine if the prototypic sigma receptor antagonist, SN79, mitigates METH-induced microglial activation and associated increases in cytokine expression in a rodent model of METH-induced neurotoxicity. METH increased striatal mRNA and protein levels of cluster of differentiation 68 (CD68), indicative of microglial activation. METH also increased ionized calcium binding adapter molecule 1 (IBA-1) protein expression, further confirming the activation of microglia. Along with microglial activation, METH increased striatal mRNA expression levels of IL-6 family pro-inflammatory cytokines, leukemia inhibitory factor (lif), oncostatin m (osm), and interleukin-6 (il-6). Pretreatment with SN79 reduced METH-induced increases in CD68 and IBA-1 expression, demonstrating its ability to prevent microglial activation. SN79 also attenuated METH-induced mRNA increases in IL-6 pro-inflammatory cytokine family members. The ability of a sigma receptor antagonist to block METH-induced microglial activation and cytokine production provides a novel mechanism through which the neurotoxic effects of METH may be mitigated.

  16. The Ubiquitin Ligase Siah2 Regulates Obesity-induced Adipose Tissue Inflammation

    PubMed Central

    Kilroy, Gail; Carter, Lauren E.; Newman, Susan; Burk, David H.; Manuel, Justin; Möller, Andreas; Bowtell, David D.; Mynatt, Randall L.; Ghosh, Sujoy; Floyd, Z. Elizabeth

    2015-01-01

    Objective Chronic, low-grade adipose tissue inflammation associated with adipocyte hypertrophy is an important link in the relationship between obesity and insulin resistance. Although ubiquitin ligases regulate inflammatory processes, the role of these enzymes in metabolically driven adipose tissue inflammation is relatively unexplored. Herein, we examined the effect of the ubiquitin ligase Siah2 on obesity-related adipose tissue inflammation. Methods Wild-type and Siah2KO mice were fed a low or high fat diet for 16 weeks. Indirect calorimetry, body composition, glucose and insulin tolerance were assayed along with glucose and insulin levels. Gene and protein expression, immunohistochemistry, adipocyte size distribution and lipolysis were also analyzed. Results Enlarged adipocytes in obese Siah2KO mice are not associated with obesity-induced insulin resistance. Proinflammatory gene expression, stress kinase signaling, fibrosis and crown-like structures are reduced in the Siah2KO adipose tissue and Siah2KO adipocytes are more responsive to insulin-dependent inhibition of lipolysis. Loss of Siah2 increases expression of PPARγ target genes involved in lipid metabolism and decreases expression of proinflammatory adipokines regulated by PPARγ. Conclusions Siah2 links adipocyte hypertrophy with adipocyte dysfunction and recruitment of proinflammatory immune cells to adipose tissue. Selective regulation of PPARγ activity is a Siah2-mediated mechanism contributing to obesity-induced adipose tissue inflammation. PMID:26380945

  17. Obesity-Induced Structural and Neuronal Plasticity in the Lateral Orbitofrontal Cortex.

    PubMed

    Thompson, Jennifer L; Drysdale, Michael; Baimel, Corey; Kaur, Manpreet; MacGowan, Taigan; Pitman, Kimberley A; Borgland, Stephanie L

    2017-01-18

    The orbitofrontal cortex (OFC) integrates sensory information with the current value of foods and updates actions based on this information. Obese humans and rats fed a cafeteria diet have impaired devaluation of food rewards, implicating a potential obesity-induced dysfunction of the OFC. We hypothesized that obesity alters OFC pyramidal neuronal structure and function and reduces conditioned suppression of feeding. Rats were given restricted (1 h/day), extended (23 h/day) or no (chow only) access to a cafeteria diet and tested for a conditioned suppression of feeding. Golgi-cox impregnation and whole-cell patch clamp experiments were performed in lateral OFC pyramidal neurons of rats from the 3 feeding groups. Rats with 40 days of extended, but not restricted, access to a cafeteria diet became obese and continued to feed during foot shock-predicting cues. Access to a cafeteria diet induced morphological changes in basilar dendrites of lateral OFC pyramidal neurons. While there were no alterations in excitatory synaptic transmission underlying altered spine density, we observed a more depolarized resting membrane potential. This was accompanied by decreased inhibitory synaptic transmission onto lateral OFC pyramidal neurons due to decreased release probability at GABAergic inputs. These changes could underlie the inability of the OFC to encode changes in the motivation value of food that is observed in obese rodents and humans.Neuropsychopharmacology advance online publication, 18 January 2017; doi:10.1038/npp.2016.284.

  18. The Inhibitory Effects of Anti-Oxidants on Ultraviolet-Induced Up-Regulation of the Wrinkling-Inducing Enzyme Neutral Endopeptidase in Human Fibroblasts

    PubMed Central

    Nakajima, Hiroaki; Terazawa, Shuko; Niwano, Takao; Yamamoto, Yorihiro; Imokawa, Genji

    2016-01-01

    We recently reported that the over-expression of skin fibroblast-derived neutral endopeptidase (NEP) plays a pivotal role in impairing the three-dimensional architecture of dermal elastic fibers during the biological mechanism of ultraviolet (UV)-induced skin wrinkling. In that process, a UVB-associated epithelial-mesenchymal cytokine interaction as well as a direct UVA-induced cellular stimulation are associated with the up-regulation of NEP in human fibroblasts. In this study, we characterized the mode of action of ubiquinol10 which may abrogate the up-regulation of NEP by dermal fibroblasts, resulting in a reported in vivo anti-wrinkling action, and compared that with 3 other anti-oxidants, astaxanthin (AX), riboflavin (RF) and flavin mononucleotide (FMN). Post-irradiation treatment with all 4 of those anti-oxidants elicited an interrupting effect on the UVB-associated epithelial-mesenchymal cytokine interaction leading to the up-regulation of NEP in human fibroblasts but with different modes of action. While AX mainly served as an inhibitor of the secretion of wrinkle-inducing cytokines, such as interleukin-1α (IL-1α) and granulocyte macrophage colony stimulatory factor (GM-CSF) in UVB-exposed epidermal keratinocytes, ubiquinol10, RF and FMN predominantly interrupted the IL-1α and GM-CSF-stimulated expression of NEP in dermal fibroblasts. On the other hand, as for the UVA-associated mechanism, similar to the abrogating effects reported for AX and FMN, ubiquinol10 but not RF had the potential to abrogate the increased expression of NEP and matrix-metalloproteinase-1 in UVA-exposed human fibroblasts. Our findings strongly support the in vivo anti-wrinkling effects of ubiquinol10 and AX on human and animal skin and provide convincing proof of the UV-induced wrinkling mechanism that essentially focuses on the over-expression of NEP by dermal fibroblasts as an intrinsic causative factor. PMID:27648570

  19. Upregulation of interferon-induced genes in infants with virus-associated acute bronchiolitis.

    PubMed

    Scagnolari, Carolina; Midulla, Fabio; Trombetti, Simona; Pierangeli, Alessandra; Tromba, Valeria; Grossi, Rosanna; Di Marco, Paola; Dianzani, Caterina; Girardi, Enrico; Antonelli, Guido

    2007-11-01

    To determine whether there is an airway IFN response in infants with acute bronchiolitis and to establish whether the rate of such a response is related to the severity of illness, the expression of some IFN-induced genes was measured in nasopharyngeal washes from 39 infants with acute bronchiolitis. The results indicate that in infants with a virus-associated acute bronchiolitis there is a strong activation of IFN system and that the severity of illness is inversely related to the level of expression of IFN-induced genes. This suggests that the IFN response plays an important role in determining virus-associated respiratory disease in early life.

  20. Increased hepatic CD36 expression contributes to dyslipidemia associated with diet-induced obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The etiology of type 2 diabetes often involves diet-induced obesity (DIO), which is associated with elevated plasma fatty acids and lipoprotein associated triglycerides. Since aberrant hepatic fatty acid uptake may contribute to this, we investigated whether increased expression of a fatty acid tran...

  1. NT-PGC-1α activation attenuates high-fat diet-induced obesity by enhancing brown fat thermogenesis and adipose tissue oxidative metabolism.

    PubMed

    Jun, Hee-Jin; Joshi, Yagini; Patil, Yuvraj; Noland, Robert C; Chang, Ji Suk

    2014-11-01

    The transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and its splice variant N terminal (NT)-PGC-1α regulate adaptive thermogenesis by transcriptional induction of thermogenic and mitochondrial genes involved in energy metabolism. We previously reported that full-length PGC-1α (FL-PGC-1α) is dispensable for cold-induced nonshivering thermogenesis in FL-PGC-1α(-/-) mice, since a slightly shorter but functionally equivalent form of NT-PGC-1α (NT-PGC-1α(254)) fully compensates for the loss of FL-PGC-1α in brown and white adipose tissue. In the current study, we challenged FL-PGC-1α(-/-) mice with a high-fat diet (HFD) to investigate the effects of diet-induced thermogenesis on HFD-induced obesity. Despite a large decrease in locomotor activity, FL-PGC-1α(-/-) mice exhibited the surprising ability to attenuate HFD-induced obesity. Reduced fat mass in FL-PGC-1α(-/-) mice was closely associated with an increase in body temperature, energy expenditure, and whole-body fatty acid oxidation (FAO). Mechanistically, FL-PGC-1α(-/-) brown adipose tissue had an increased capacity to oxidize fatty acids and dissipate energy as heat, in accordance with upregulation of thermogenic genes UCP1 and DIO2. Furthermore, augmented expression of FAO and lipolytic genes in FL-PGC-1α(-/-) white adipose tissue was highly correlated with decreased fat storage in adipose tissue. Collectively, our data highlight a protective effect of NT-PGC-1α on diet-induced obesity by enhancing diet-induced thermogenesis and FAO.

  2. Gelidium amansii extract ameliorates obesity by down-regulating adipogenic transcription factors in diet-induced obese mice

    PubMed Central

    Kang, Ji-Hye; Lee, Hyun-Ah; Kim, Hak-Ju

    2017-01-01

    BACKGROUND/OBJECTIVES In this study, we investigated whether Gelidium amansii extract (GAE) ameliorates obesity in diet-induced obese (DIO) mice. MATERIALS/METHODS The mice were maintained on a high-fat diet (HD) for 5 weeks to generate the DIO mouse model. And then mice fed HD plus 0.5% (GAE1), 1% (GAE2) or 2% (GAE3) for 8 weeks. RESULTS After the experimental period, GAE-supplemented groups were significantly lower than the HD group in body weight gain and liver weight. GAE supplemented groups were significantly lower than the HD group in both epididymal and mesenteric adipose tissue mass. The plasma leptin level was significantly higher in the HD group than in GAE-supplemented groups. The leptin level of HD+GAE3 group was significantly lower than that of the HD+conjugated linoleic acid (CLA) group. In contrast, plasma adiponectin level of the HD group was significantly lower than those of HD+GAE2 and HD+GAE3 groups. The expression levels of adipogenic proteins such as fatty acid synthase, sterol regulatory element-binding protein-1c, peroxisome proliferator-activated receptor γ, and CCAAT/enhancer binding protein α in the GAE supplemented groups were significantly decreased than those in HD group, respectively. In addition, the expression levels of HD+GAE2 and HD+GAE3 groups are significantly decreased compared to those of HD+CLA group. On the contrary, the expression levels of hormone-sensitive lipase and phospho-AMP-activated protein kinase, proteins associated with lipolysis, were significantly increased in the GAE supplemented groups compared to those in the HD group. HD+GAE3 group showed the highest level among the GAE supplemented groups. CONCLUSIONS These results suggested that GAE supplementation stimulated the expressions of lipid metabolic factors and reduced weight gain in HD-fed C57BL/6J obese mice. PMID:28194261

  3. Berberine up-regulates the BDNF expression in hippocampus and attenuates corticosterone-induced depressive-like behavior in mice.

    PubMed

    Shen, Ji-Duo; Ma, Li-Gang; Hu, Chun-Yue; Pei, Yang-Yi; Jin, Shuang-Li; Fang, Xiao-Yan; Li, Yu-Cheng

    2016-02-12

    Depression is increasingly become a global public healthy problem. This study was to investigate whether berberine could attenuate the depressive-like behavior induced by repeated corticosterone injection and explore the possible mechanisms. The present results showed that exogenous corticosterone injection caused depressive-like behaviors in mice, such as decreased sucrose intake in sucrose preference test (SPT) and increased immobility time in forced swimming test (FST). These behavioral alterations were accompanying with the decreased BDNF mRNA and protein levels in hippocampus and the elevated serum corticosterone levels. Treatment with berberine prevented these changes above. Our findings confirmed the antidepressant-like effect of berberine and suggested its mechanisms might be partially mediated by up-regulation of BDNF in hippocampus.

  4. Propofol induces apoptosis of hepatocellular carcinoma cells by upregulation of microRNA-199a expression.

    PubMed

    Zhang, Jian; Wu, Guo-qing; Zhang, Yan; Feng, Zhi-ying; Zhu, Sheng-mei

    2013-03-01

    Propofol is one of the extensively commonly used intravenous anaesthetic agents. The effects of Propofol on hepatocellular carcinoma (HCC) growth inhibition and apoptosis have been examined. The techniques used were the MTT assay, flow cytometry, real-time PCR to assess miR-199a expression, as also caspase-8 and caspase-9 activity in HepG2 cells treated with Propofol. Finally, we evaluated the effect of miR-199a on Propofol-induced anti-tumour activity using anti-miR-199a. Propofol efficiently inhibited the growth of HCC cells, but was less toxic to normal hepatic cells. It induced apoptosis and increased expression of miR-199a. Activation of caspase-8 and caspase-9 suggested that both extrinsic and intrinsic pathways are involved in Propofol-induced apoptosis. Anti-miR-199a reversed the effect of Propofol on apoptosis and activation of caspase-8 and caspase-9 in HepG2 cells. Propofol can effectively induce apoptosis of HCC cells and modulation of miR-199a possibly contributes to the anti-tumour action of Propofol. Hence, Propofol might be an effective drug for HCC.

  5. STAT3 upregulation in pituitary somatotroph adenomas induces growth hormone hypersecretion.

    PubMed

    Zhou, Cuiqi; Jiao, Yonghui; Wang, Renzhi; Ren, Song-Guang; Wawrowsky, Kolja; Melmed, Shlomo

    2015-04-01

    Pituitary somatotroph adenomas result in dysregulated growth hormone (GH) hypersecretion and acromegaly; however, regulatory mechanisms that promote GH hypersecretion remain elusive. Here, we provide evidence that STAT3 directly induces somatotroph tumor cell GH. Evaluation of pituitary tumors revealed that STAT3 expression was enhanced in human GH-secreting adenomas compared with that in nonsecreting pituitary tumors. Moreover, STAT3 and GH expression were concordant in a somatotroph adenoma tissue array. Promoter and expression analysis in a GH-secreting rat cell line (GH3) revealed that STAT3 specifically binds the Gh promoter and induces transcription. Stable expression of STAT3 in GH3 cells induced expression of endogenous GH, and expression of a constitutively active STAT3 further enhanced GH production. Conversely, expression of dominant-negative STAT3 abrogated GH expression. In primary human somatotroph adenoma-derived cell cultures, STAT3 suppression with the specific inhibitor S3I-201 attenuated GH transcription and reduced GH secretion in the majority of derivative cultures. In addition, S3I-201 attenuated somatotroph tumor growth and GH secretion in a rat xenograft model. GH induced STAT3 phosphorylation and nuclear translocation, indicating a positive feedback loop between STAT3 and GH in somatotroph tumor cells. Together, these results indicate that adenoma GH hypersecretion is the result of STAT3-dependent GH induction, which in turn promotes STAT3 expression, and suggest STAT3 as a potential therapeutic target for pituitary somatotroph adenomas.

  6. `Up-regulation of histone acetylation induced by social defeat mediates the conditioned rewarding effects of cocaine.

    PubMed

    Montagud-Romero, S; Montesinos, J; Pascual, M; Aguilar, M A; Roger-Sanchez, C; Guerri, C; Miñarro, J; Rodríguez-Arias, M

    2016-10-03

    Social defeat (SD) induces a long-lasting increase in the rewarding effects of psychostimulants measured using the self-administration and conditioned place procedures (CPP). However, little is known about the epigenetic changes induced by social stress and about their role in the increased response to the rewarding effects of psychostimulants. Considering that histone acetylation regulates transcriptional activity and contributes to drug-induced behavioral changes, we addressed the hypothesis that SD induces transcriptional changes by histone modifications associated with the acquisition of place conditioning. After a fourth defeat, H3(K9) acetylation was decreased in the hippocampus, while there was an increase of HAT and a decrease of HDAC levels in the cortex. Three weeks after the last defeat, mice displayed an increase in histone H4(K12) acetylation and an upregulation of histone acetyl transferase (HAT) activity in the hippocampus. In addition, H3(K4)me3, which is closely associated with transcriptional initiation, was also augmented in the hippocampus three weeks after the last defeat. Inhibition of HAT by curcumin (100mg/kg) before each SD blocked the increase in the conditioned reinforcing effects of 1mg/kg of cocaine, while inhibition of HDAC by valproic acid (500mg/kg) before social stress potentiated cocaine-induced CPP. Preference was reinstated when animals received a priming dose of 0.5mg/kg of cocaine, an effect that was absent in untreated defeated mice. These results suggest that the experience of SD induces chromatin remodeling, alters histone acetylation and methylation, and modifies the effects of cocaine on place conditioning. They also point to epigenetic mechanisms as potential avenues leading to new treatments for the long-term effects of social stress on drug addiction.

  7. Moclobemide upregulated Bcl-2 expression and induced neural stem cell differentiation into serotoninergic neuron via extracellular-regulated kinase pathway

    PubMed Central

    Chiou, Shih-Hwa; Ku, Hung-Hai; Tsai, Tung-Hu; Lin, Heng-Liang; Chen, Li-Hsin; Chien, Chan-Shiu; Ho, Larry L -T; Lee, Chen-Hsen; Chang, Yuh-Lih

    2006-01-01

    Moclobemide (MB) is an antidepressant drug that selectively and reversibly inhibits monoamine oxidase-A. Recent studies have revealed that antidepressant drugs possess the characters of potent growth-promoting factors for the development of neurogenesis and improve the survival rate of serotonin (5-hydroxytrytamine; 5-HT) neurons. However, whether MB comprises neuroprotection effects or modulates the proliferation of neural stem cells (NSCs) needs to be elucidated. In this study, firstly, we used the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to demonstrate that 50 μM MB can increase the cell viability of NSCs. The result of real-time reverse transcription–polymerase chain reaction (RT–PCR) showed that the induction of MB can upregulate the gene expressions of Bcl-2 and Bcl-xL. By using caspases 8 and 3, ELISA and terminal dUTP nick-end labeling (TUNEL) assay, our data further confirmed that 50 μM MB-treated NSCs can prevent FasL-induced apoptosis. The morphological findings also supported the evidence that MB can facilitate the dendritic development and increase the neurite expansion of NSCs. Moreover, we found that MB treatment increased the expression of Bcl-2 in NSCs through activating the extracellular-regulated kinase (ERK) phosphorylation. By using the triple-staining immunofluorescent study, the percentages of serotonin- and MAP-2-positive cells in the day 7 culture of MB-treated NSCs were significantly increased (P<0.01). Furthermore, our data supported that MB treatment increased functional production of serotonin in NSCs via the modulation of ERK1/2. In sum, the study results support that MB can upregulate Bcl-2 expression and induce the differentiation of NSCs into serotoninergic neuron via ERK pathway. PMID:16702990

  8. Uterine Expression of NDRG4 Is Induced by Estrogen and Up-Regulated during Embryo Implantation Process in Mice

    PubMed Central

    Zhang, Xuan; Wang, Jian-Mei; He, Ya-Ping; Shi, Yan; Sun, Zhao-Gui; Shi, Hui-Juan; Wang, Jian

    2016-01-01

    Embryo implantation is an essential step for the establishment of pregnancy and dynamically regulated by estrogen and progesterone. NDRG4 (N-myc down-regulated gene 4) is a tumor suppressor that participates in cell survival, tumor invasion and angiogenesis. The objective of this study was to preliminarily explore the role of NDRG4 in embryo implantation. By immunohistochemistry (IHC) and quantitive RT-PCR (qRT-PCR), we found that uterine expression of NDRG4 was increased along with puberal development, and its expression in adult females reached the peak at the estrus stage during the estrus cycle. Furthermore, uterine NDRG4 expression was significantly induced by the treatment of estradiol (E2) both in pre-puberty females and ovariectomized adult females. Uterine expression pattern of NDRG4 during the peri-implantation period in mice was determined by IHC, qRT-PCR and Western blot. It was observed that NDRG4 expression was up-regulated during the implantation process, and its expression level at the implantation sites was significantly higher than that at the inter-implantation sites. Meanwhile, an increased expression in NDRG4 was associated with artificial decidualization as well as the activation of delayed implantation. By qRT-PCR and Western blot, we found that the in vitro decidualization of endometrial stromal cells (ESCs) was accompanied by up-regulation of NDRG4 expression, whereas knockdown of its expression in these cells by siRNA inhibited the decidualization process. In addition, Western blot analysis showed that NDRG4 protein expression was decreased in human villus tissues of recurrent miscarriage (RM) patients compared to normal pregnant women. Collectively, these data suggested that uterine NDRG4 expression could be induced by estrogen, and NDRG4 might play an important role during early pregnancy. PMID:27175791

  9. Preparation of a nano emodin transfersome and study on its anti-obesity mechanism in adipose tissue of diet-induced obese rats

    PubMed Central

    2014-01-01

    Objective To describe the preparation of nano emodin transfersome (NET) and investigate its effect on mRNA expression of adipose triglyceride lipase (ATGL) and G0/G1 switch gene 2 (G0S2) in adipose tissue of diet-induced obese rats. Methods NET was prepared by film-ultrasonic dispersion method. The effects of emodin components at different ratios on encapsulation efficiency were investigated.The NET envelopment rate was determined by ultraviolet spectrophotometry. The particle size and Zeta potential of NET were evaluated by Zetasizer analyzer. Sixty male SD rats were assigned to groups randomly. After 8-week treatment, body weight, wet weight of visceral fat and the percentage of body fat (PBF) were measured. Fasting blood glucose and serum lipid levels were determined. The adipose tissue section was HE stained, and the cellular diameter and quantity of adipocytes were evaluated by light microscopy. The mRNA expression of ATGL and G0S2 from the peri-renal fat tissue was assayed by RT-PCR. Results The appropriate formulation was deoxycholic acid sodium salt vs. phospholipids 1:8, cholesterol vs. phospholipids 1:3, vitamin Evs. phospholipids 1:20, and emodin vs. phospholipid 1:6. Zeta potential was −15.11 mV, and the particle size was 292.2 nm. The mean encapsulation efficiency was (69.35 ± 0.25)%. Compared with the obese model group, body weight, wet weight of visceral fat, PBF and mRNA expression of G0S2 from peri-renal fat tissue were decreased significantly after NET treatment (all P < 0.05), while high-density lipoprotein cholesterol (HDL-C), the diameter of adipocytes and mRNA expression of ATGL from peri-renal fat tissue were increased significantly (all P < 0.05). Conclusion The preparation method is simple and reasonable. NET with negative electricity was small and uniform in particle size, with high encapsulation efficiency and stability. NET could reduce body weight and adipocyte size, and this effect was associated with the up-regulation of

  10. Diet enriched with korean pine nut oil improves mitochondrial oxidative metabolism in skeletal muscle and brown adipose tissue in diet-induced obesity.

    PubMed

    Le, Ngoc Hoan; Shin, Sunhye; Tu, Thai Hien; Kim, Chu-Sook; Kang, Ji-Hye; Tsuyoshi, Goto; Teruo, Kawada; Han, Sung Nim; Yu, Rina

    2012-12-05

    In this study, we investigated effects of pine nut oil (PNO) on high-fat-diet (HFD)-induced obesity and metabolic dysfunction in skeletal muscle and brown adipose tissue (BAT). Male C57BL/6 mice were fed a HFD with 15% energy from lard and 30% energy from either soybean oil (SBO-HFD) or PNO (PNO-HFD) for 12 weeks. The PNO-HFD resulted in less weight gain and intramuscular lipid accumulation than the SBO-HFD and was accompanied by upregulation of transcripts and proteins related to oxidative metabolism and phosphorylation of AMP-activated protein kinase (AMPK), as well as molecules selectively expressed in type I and type IIa muscle fibers. In addition, uncoupling protein-1 was upregulated in BAT. These beneficial metabolic effects were partly associated with the dual ligand activity of pinolenic acid, which is abundant in PNO, for peroxisome proliferator-activated receptors α and δ. Our findings suggest that PNO may have potential as a dietary supplement for counteracting obesity and metabolic dysregulation.

  11. Radiographic evaluation of the effect of obesity on alveolar bone in rats with ligature-induced periodontal disease

    PubMed Central

    do Nascimento, Cassiane Merigo; Cassol, Tiago; da Silva, Fernanda Soares; Bonfleur, Maria Lucia; Nassar, Carlos Augusto; Nassar, Patricia Oehlmeyer

    2013-01-01

    There is evidence that the lack of metabolic control of obese patients may accelerate periodontitis. The aim of this study was to evaluate radiographically the effect of cafeteria-diet-induced obesity on alveolar bone loss in rats subjected to periodontal disease. Twenty male Wistar rats were randomly divided into four groups: 1) control group, 2) control and ligature group; 3) cafeteria group; and 4) cafeteria and ligature group. The animals were evaluated for obesity and euthanized, and the mandible of each rat was removed to perform a radiographic evaluation of alveolar bone loss and its effect on diet-induced obesity. The results showed greater alveolar bone loss in the mice in Group 4 (P<0.01). Thus, we concluded that obese mice, on average, showed greater radiographic evidence of alveolar bone loss than mice undergoing induction of obesity. PMID:24124386

  12. Up-regulation of cholesterol absorption is a mechanism for cholecystokinin-induced hypercholesterolemia.

    PubMed

    Zhou, LiChun; Yang, Hong; Okoro, Emmanuel U; Guo, Zhongmao

    2014-05-09

    Excessive absorption of intestinal cholesterol is a risk factor for atherosclerosis. This report examines the effect of cholecystokinin (CCK) on plasma cholesterol level and intestinal cholesterol absorption using the in vivo models of C57BL/6 wild-type and low density lipoprotein receptor knock-out (LDLR(-/-)) mice. These data were supported by in vitro studies involving mouse primary intestinal epithelial cells and human Caco-2 cells; both express CCK receptor 1 and 2 (CCK1R and CCK2R). We found that intravenous injection of [Thr(28),Nle(31)]CCK increased plasma cholesterol levels and intestinal cholesterol absorption in both wild-type and LDLR(-/-) mice. Treatment of mouse primary intestinal epithelial cells with [Thr(28),Nle(31)]CCK increased cholesterol absorption, whereas selective inhibition of CCK1R and CCK2R with antagonists attenuated CCK-induced cholesterol absorption. In Caco-2 cells, CCK enhanced CCK1R/CCK2R heterodimerization. Knockdown of both CCK1R and CCK2 or either one of them diminished CCK-induced cholesterol absorption to the same extent. CCK also increased cell surface-associated NPC1L1 (Niemann-Pick C1-like 1) transporters but did not alter their total protein expression. Inhibition or knockdown of NPC1L1 attenuated CCK-induced cholesterol absorption. CCK enhanced phosphatidylinositide 3-kinase (PI3K) and Akt phosphorylation and augmented the interaction between NPC1L1 and Rab11a (Rab-GTPase-11a), whereas knockdown of CCK receptors or inhibition of G protein βγ dimer (Gβγ) diminished CCK-induced PI3K and Akt phosphorylation. Inhibition of PI3K and Akt or knockdown of PI3K diminished CCK-induced NPC1L1-Rab11a interaction and cholesterol absorption. Knockdown of Rab11a suppressed CCK-induced NPC1L1 translocation and cholesterol absorption. These data imply that CCK enhances cholesterol absorption by activation of a pathway involving CCK1R/CCK2R, Gβγ, PI3K, Akt, Rab11a, and NPC1L.

  13. Atorvastatin attenuates TNF-α-induced increase of glucose oxidation through PGC-1α upregulation in cardiomyocytes.

    PubMed

    Gao, Feng; Ni, Yinxing; Luo, Zhidan; Liang, Yi; Yan, Zhencheng; Xu, Xingsen; Liu, Daoyan; Wang, Jiang; Zhu, Shanjun; Zhu, Zhiming

    2012-06-01

    Recent studies have shown that atorvastain has anti-inflammatory effect and can prevent cardiac hypertrophy. The development of cardiac hypertrophy and dysfunction is associated with an increase in cardiac glucose utilization. In this study, we investigated the effect of atorvastatin on glucose oxidation in tumor necrosis factor α (TNF-α)-stimulated cardiomyocytes (H9c2 cells) and the potential role of peroxisome proliferation-activated receptor coactivator 1α (PGC-1α) in this effect. Exposure of H9c2 cells to TNF-α inhibited the expressions of PGC-1α, pyruvate dehydrogenase kinase 4, and carnitine palmityl transferase 1 and induced a significant increase in glucose oxidation rate. However, the effects of TNF-α were significantly reversed by atorvastatin. Selective silence of PGC-1α in H9c2 cells resulted in the downregulation of pyruvate dehydrogenase kinase 4 and carnitine palmityl transferase 1 and further increased the TNF-α-induced glucose oxidation. Interestingly, the effect of atorvastatin on PGC-1α was almost abolished by mevalonate and partially by farnesol but not by geranylgeraniol. In conclusion, atorvastatin inhibits TNF-α-induced glucose oxidation through PGC-1α upregulation in cardiomyocytes, which might be associated with the regulation of isoprenoid metabolites.

  14. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser

    PubMed Central

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S.; Gonzalez-Lima, F.; Liu, Hanli

    2016-01-01

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT. PMID:27484673

  15. Resveratrol suppresses NTHi-induced inflammation via up-regulation of the negative regulator MyD88 short

    PubMed Central

    Andrews, Carla S.; Matsuyama, Shingo; Lee, Byung-Cheol; Li, Jian-Dong

    2016-01-01

    Upper respiratory tract inflammatory diseases such as asthma and chronic obstructive pulmonary diseases (COPD) affect more than one-half billion people globally and are characterized by chronic inflammation that is often exacerbated by respiratory pathogens such as nontypeable Haemophilus influenzae (NTHi). The increasing numbers of antibiotic-resistant bacterial strains and the limited success of currently available pharmaceuticals used to manage the symptoms of these diseases present an urgent need for the development of novel anti-inflammatory therapeutic agents. Resveratrol has long been thought as an interesting therapeutic agent for various diseases including inflammatory diseases. However, the molecular mechanisms underlying its anti-inflammatory properties remain largely unknown. Here we show for the first time that resveratrol decreases expression of pro-inflammatory mediators in airway epithelial cells and in the lung of mice by enhancing NTHi-induced MyD88 short, a negative regulator of inflammation, via inhibition of ERK1/2 activation. Furthermore, resveratrol inhibits NTHi-induced ERK1/2 phosphorylation by increasing MKP-1 expression via a cAMP-PKA-dependent signaling pathway. Finally, we show that resveratrol has anti-inflammatory effects post NTHi infection, thereby demonstrating its therapeutic potential. Together these data reveal a novel mechanism by which resveratrol alleviates NTHi-induced inflammation in airway disease by up-regulating the negative regulator of inflammation MyD88s. PMID:27677845

  16. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser.

    PubMed

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S; Gonzalez-Lima, F; Liu, Hanli

    2016-08-03

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT.

  17. Hypoxia induces upregulation of the deoxyribonuclease I gene in the human pancreatic cancer cell line QGP-1.

    PubMed

    Kominato, Yoshihiko; Iida, Reiko; Nakajima, Tamiko; Tajima, Yutaka; Takagi, Rie; Makita, Chikako; Kishi, Koichiro; Ueki, Misuzu; Kawai, Yasuyuki; Yasuda, Toshihiro

    2007-11-01

    We have previously demonstrated that ischemia caused by acute myocardial infarction induces an abrupt increase of serum deoxyribonuclease I (DNase I) activity. In this study, we examined whether hypoxia can affect the levels of DNase I activity and/or its transcripts in vitro. We first exposed the human pancreatic cancer cell line QGP-1, which is the first documented DNase-I-producing cell line, to hypoxia (2% O2), and found that this induced a significant increase in both the activity and transcripts of DNase I. This response was mediated by increased transcription only from exon 1a of the two alternative transcription-initiating exons utilized simultaneously in the human DNase I gene (DNASE1); exposure of QGP-1 cells to hypoxia for 24 h resulted in a 15-fold increase of DNASE1 transcripts starting from exon 1a compared with the expression level under normoxic conditions. Promoter, electrophoretic mobility shift, and chromatin immunoprecipitation assays with QGP-1 cells exposed to hypoxia or normoxia showed that the region just upstream from exon 1a was involved in this response in a hypoxia-induced factor-1-independent, but at least in a Sp1 transcription factor-dependent manner possibly through enhanced binding of Sp1 protein to the promoter. These results indicate that DNASE1 expression is upregulated by hypoxia in the cells.

  18. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser

    NASA Astrophysics Data System (ADS)

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S.; Gonzalez-Lima, F.; Liu, Hanli

    2016-08-01

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT.

  19. BEX4 upregulation alters Sertoli cell growth properties and protein expression profiles: An explanation for cadmium-induced testicular Sertoli cell injury.

    PubMed

    Yu, Wu; Yaping, Liu; Mingjun, Wu; Jie, Hao; Xiaogang, Liao; Gang, Li

    2017-03-15

    Increasing evidence has demonstrated that cadmium (Cd) may induce testicular dysfunction by targeting genes that are expressed in the testis. Here, we demonstrated that BEX4 is expressed in testis Sertoli cells, and its expression was significantly upregulated by CdCl2 treatment through activating the p38 signaling pathway. To investigate whether augmented BEX4 expression affects Sertoli cell growth and function, BEX4-overexpressing TM4 Sertoli cells were established. Proteomics analysis identified 85 differentially expressed proteins in BEX4-overexpressing cells. Bioinformatics analysis revealed that most of the significantly upregulated proteins had functional implications in cellular metabolic processes, whereas those that were downregulated were mostly related to cell cycle and cell communication. Therefore, the present study provides the first evidence that BEX4 upregulation induces alterations in Sertoli cell growth properties and protein expression profiles, which may be an explanation for Cd-induced testicular Sertoli cell injury.

  20. Anti-Obesity Effect of the CB2 Receptor Agonist JWH-015 in Diet-Induced Obese Mice.

    PubMed

    Verty, A N A; Stefanidis, A; McAinch, A J; Hryciw, D H; Oldfield, Brian

    2015-01-01

    The cannabinoid receptor 2 (CB2) is well known for its immune modulatory role. However, recent localisation of CB2 receptors in metabolically active tissue suggests that the CB2 receptor plays a significant role in energy homeostasis. This study was designed to investigate the impact of chronic CB2 receptor stimulation on food intake, body weight and mood. Lean male C57BL/6 mice were injected i.p. with the selective CB2 receptor agonist, JWH-015 (0.0, 1.0, 5.0 and 10.0 mg kg-1) to establish dose response parameters. Mice made obese following exposure to a diet consisting of 19.4 MJ/kg (4641 Kcal/kg) of energy (19.0% protein, 21.0% total fat, 4.7% crude fiber, and 4.7% AD fiber were given either vehicle or 10 mg/kg JWH-015. Impact on mood, food intake, body weight, plasma metabolites, expression of key metabolic proteins in the brown adipose tissue (BAT) and white adipose tissue (WAT), and markers of inflammation were measured. High dose (10 mg/kg) JWH-015 reduced food intake after 1, 2, 4, and 24 h in lean mice. When given to diet induced obese (DIO) mice, a 10 mg/kg dose of JWH-015 significantly reduced body weight compared to vehicle. This dose led to a shift in markers of lipid metabolism and inflammation in WAT consistent with lipolysis and improved immune response. Furthermore, JWH-015 (10 mg/kg) produced a transient reduction in food intake and significant reduction in fat mass and adipocyte cell size. Importantly, JWH-015 produced an anxiolytic response in the elevated plus maze while having no effect on immobility time in the forced swim test. It should be noted that though the 10 mg/kg dose produced positive effects on the obese state, the possibility that these effects are mediated via non-CB2 receptor mechanisms cannot be ruled out. These results demonstrate a role for CB2 receptors in modulating energy homeostasis and obesity associated metabolic pathologies in the absence of any adverse impact on mood.

  1. Anti-Obesity Effect of the CB2 Receptor Agonist JWH-015 in Diet-Induced Obese Mice

    PubMed Central

    Verty, A. N. A.; Stefanidis, A.; McAinch, A. J.; Hryciw, D. H.; Oldfield, Brian

    2015-01-01

    The cannabinoid receptor 2 (CB2) is well known for its immune modulatory role. However, recent localisation of CB2 receptors in metabolically active tissue suggests that the CB2 receptor plays a significant role in energy homeostasis. This study was designed to investigate the impact of chronic CB2 receptor stimulation on food intake, body weight and mood. Lean male C57BL/6 mice were injected i.p. with the selective CB2 receptor agonist, JWH-015 (0.0, 1.0, 5.0 and 10.0 mg kg-1) to establish dose response parameters. Mice made obese following exposure to a diet consisting of 19.4 MJ/kg (4641 Kcal/kg) of energy (19.0% protein, 21.0% total fat, 4.7% crude fiber, and 4.7% AD fiber were given either vehicle or 10 mg/kg JWH-015. Impact on mood, food intake, body weight, plasma metabolites, expression of key metabolic proteins in the brown adipose tissue (BAT) and white adipose tissue (WAT), and markers of inflammation were measured. High dose (10 mg/kg) JWH-015 reduced food intake after 1, 2, 4, and 24 h in lean mice. When given to diet induced obese (DIO) mice, a 10 mg/kg dose of JWH-015 significantly reduced body weight compared to vehicle. This dose led to a shift in markers of lipid metabolism and inflammation in WAT consistent with lipolysis and improved immune response. Furthermore, JWH-015 (10 mg/kg) produced a transient reduction in food intake and significant reduction in fat mass and adipocyte cell size. Importantly, JWH-015 produced an anxiolytic response in the elevated plus maze while having no effect on immobility time in the forced swim test. It should be noted that though the 10 mg/kg dose produced positive effects on the obese state, the possibility that these effects are mediated via non-CB2 receptor mechanisms cannot be ruled out. These results demonstrate a role for CB2 receptors in modulating energy homeostasis and obesity associated metabolic pathologies in the absence of any adverse impact on mood. PMID:26588700

  2. Paprika Pigments Attenuate Obesity-Induced Inflammation in 3T3-L1 Adipocytes

    PubMed Central

    Maeda, Hayato; Saito, Shuuichi; Nakamura, Nozomi; Maoka, Takashi

    2013-01-01

    Obesity is related to various diseases, such as diabetes, hyperlipidemia, and hypertension. Adipocytokine, which is released from adipocyte cells, affects insulin resistance and blood lipid level disorders. Further, adipocytokine is related to chronic inflammation in obesity condition adipocyte cells. Paprika pigments (PPs) contain large amounts of capsanthin and capsorubin. These carotenoids affect the liver and improve lipid disorders of the blood. However, how these carotenoids affect adipocyte cells remains unknown. Present study examined the effects of PP on adipocytokine secretion, which is related to improvement of metabolic syndrome. In addition, suppressive effects of PP on chronic inflammation in adipocyte cells were analyzed using 3T3-L1 adipocyte cells and macrophage cell coculture experiments. PP promoted 3T3-L1 adipocyte cells differentiation upregulated adiponectin mRNA expression and secretion. Further, coculture of adipocyte and macrophage cells treated with PP showed suppressed interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), and resistin mRNA expression, similarly to treatment with troglitazone, which is a PPARγ ligand medicine. Conclusion. These results suggest that PP ameliorates chronic inflammation in adipocytes caused by obesity. PP adjusts adipocytokine secretion and might, therefore, affect antimetabolic syndrome diseases. PMID:24049664

  3. Enhanced glucose-induced intracellular signaling promotes insulin hypersecretion: pancreatic beta-cell functional adaptations in a model of genetic obesity and prediabetes.

    PubMed

    Irles, Esperanza; Ñeco, Patricia; Lluesma, Mónica; Villar-Pazos, Sabrina; Santos-Silva, Junia Carolina; Vettorazzi, Jean F; Alonso-Magdalena, Paloma; Carneiro, Everardo M; Boschero, Antonio C; Nadal, Ángel; Quesada, Ivan

    2015-03-15

    Obesity is associated with insulin resistance and is known to be a risk factor for type-2 diabetes. In obese individuals, pancreatic beta-cells try to compensate for the increased insulin demand in order to maintain euglycemia. Most studies have reported that this adaptation is due to morphological changes. However, the involvement of beta-cell functional adaptations in this process needs to be clarified. For this purpose, we evaluated different key steps in the glucose-stimulated insulin secretion (GSIS) in intact islets from female ob/ob obese mice and lean controls. Obese mice showed increased body weight, insulin resistance, hyperinsulinemia, glucose intolerance and fed hyperglycemia. Islets from ob/ob mice exhibited increased glucose-induced mitochondrial activity, reflected by enhanced NAD(P)H production and mitochondrial membrane potential hyperpolarization. Perforated patch-clamp examination of beta-cells within intact islets revealed several alterations in the electrical activity such as increased firing frequency and higher sensitivity to low glucose concentrations. A higher intracellular Ca(2+) mobilization in response to glucose was also found in ob/ob islets. Additionally, they displayed a change in the oscillatory pattern and Ca(2+) signals at low glucose levels. Capacitance experiments in intact islets revealed increased exocytosis in individual ob/ob beta-cells. All these up-regulated processes led to increased GSIS. In contrast, we found a lack of beta-cell Ca(2+) signal coupling, which could be a manifestation of early defects that lead to beta-cell malfunction in the progression to diabetes. These findings indicate that beta-cell functional adaptations are an important process in the compensatory response to obesity.

  4. Diet‐induced obese mice exhibit altered immune responses to acute lung injury induced by Escherichia coli

    PubMed Central

    Wan, Taomei; Yuan, Guiqiang; Ren, Yi; Wang, Zhengyi; Jia, Yiping; Cui, Hengmin; Peng, Xi; Fang, Jing; Deng, Junliang; Yu, Shumin; Hu, Yanchun; Shen, Liuhong; Ma, Xiaoping; Wang, Ya; Ren, Zhihua

    2016-01-01

    Objective Obesity has been associated with impaired immunity and increased susceptibility to bacterial infection. It also exerts protective effects against mortality secondary to acute lung injury. The effects of obesity on immune responses to acute lung injury induced by Escherichia coli were investigated to determine if the above‐mentioned differences in its effects were related to infection severity. Methods Diet‐induced obesity (DIO) and lean control mice received intranasal instillations of 109 or 1010 CFUs of E. coli. The immune responses were examined at 0 h (uninfected), 24 h, and 96 h postinfection. Results Following infection, the DIO mice exhibited higher leukocyte, interleukin (IL)−10, IL‐6, and tumor necrosis factor‐α levels and more severe lung injury than the lean mice. Following inoculation with 1010 CFUs of E. coli, the DIO mice exhibited higher mortality and more severe inflammation‐induced injury than the lean mice, but no differences in E. coli counts were noted between the two groups. However, inoculated with 109 CFUs of E. coli, the DIO mice exhibited smaller E. coli burdens at 24 h and 96 h after infection, as well as lower concentrations of IL‐10 and tumor necrosis factor‐α and less severe lung injury at 96 h after infection. Conclusions The results support the emerging view that obesity may be beneficial in the setting of milder infection but detrimental in the setting of more severe infection. PMID:27558300

  5. Upregulation of NOXA by 10-Hydroxycamptothecin plays a key role in inducing fibroblasts apoptosis and reducing epidural fibrosis

    PubMed Central

    Li, Xiaolei; He, Jun

    2017-01-01

    The fibrosis that develops following laminectomy or discectomy often causes serious complications, and the proliferation of fibroblasts is thought to be the major cause of epidural fibrosis. 10-Hydroxycamptothecin (HCPT) has been proven to be efficient in preventing epidural fibrosis, but the exact mechanism is still unclear. NOXA is a significant regulator of cell apoptosis, which has been reported to be beneficial in the treatment of fibrosis. We performed a series of experiments, both in vitro and in vivo, to explore the intrinsic mechanism of HCPT that underlies the induction of apoptosis in fibroblasts, and also to investigate whether HCPT has positive effects on epidural fibrosis following laminectomy in rats. Fibroblasts were cultured in vitro and stimulated by varying concentrations of HCPT (0, 1, 2, 4 µg/ml) for various durations (0, 24, 48, 72 h); the effect of HCPT in inducing the apoptosis of fibroblasts was investigated via Western blots and TUNEL assay. Our results showed that HCPT could induce apoptosis in fibroblasts and up-regulate the expression of NOXA. Following the knockdown of NOXA in fibroblasts, the results of Western blot analysis showed that the level of apoptotic markers, such as cleaved-PARP and Bax, was decreased. The results from the TUNEL assay also showed a decreased rate of apoptosis in NOXA-knocked down fibroblasts. For the in vivo studies, we performed a laminectomy at the L1-L2 levels in rats and applied HCPT of different concentrations (0.2, 0.1, 0.05 mg/ml and saline) locally; the macroscopic histological assessment, hydroxyproline content analysis and histological staining were performed to evaluate the effect of HCPT on reducing epidural fibrosis. The TUNEL assay in epidural tissues showed that HCPT could obviously induce apoptosis in fibroblasts in a dose-dependent manner. Also, immunohistochemical staining showed that the expression of NOXA increased as the concentrations of HCPT increased. Our findings are the first to

  6. Carnitine palmitoyltransferase-1 up-regulation by PPAR-β/δ prevents lipid-induced endothelial dysfunction.

    PubMed

    Toral, Marta; Romero, Miguel; Jiménez, Rosario; Mahmoud, Ayman Moawad; Barroso, Emma; Gómez-Guzmán, Manuel; Sánchez, Manuel; Cogolludo, Ángel; García-Redondo, Ana B; Briones, Ana M; Vázquez-Carrera, Manuel; Pérez-Vizcaíno, Francisco; Duarte, Juan

    2015-11-01

    Fatty acids cause endothelial dysfunction involving increased ROS (reactive oxygen species) and reduced NO (nitric oxide) bioavailability. We show that in MAECs (mouse aortic endothelial cells), the PPARβ/δ (peroxisome- proliferator-activated receptor β/δ) agonist GW0742 prevented the decreased A23187-stimulated NO production, phosphorylation of eNOS (endothelial nitric oxide synthase) at Ser1177 and increased intracellular ROS levels caused by exposure to palmitate in vitro. The impaired endothelium-dependent relaxation to acetylcholine in mouse aorta induced by palmitate was restored by GW0742. In vivo, GW0742 treatment prevented the reduced aortic relaxation, phosphorylation of eNOS at Ser1177, and increased ROS production and NADPH oxidase in mice fed on a high-fat diet. The PPARβ/δ antagonist GSK0660 abolished all of these protective effects induced by GW0742. This agonist enhanced the expression of CPT (carnitine palmitoyltransferase)-1. The effects of GW0742 on acetylcholine- induced relaxation in aorta and on NO and ROS production in MAECs exposed to palmitate were abolished by the CPT-1 inhibitor etomoxir or by siRNA targeting CPT-1. GW0742 also inhibited the increase in DAG (diacylglycerol), PKCα/βII (protein kinase Cα/βII) activation, and phosphorylation of eNOS at Thr495 induced by palmitate in MAECs, which were abolished by etomoxir. In conclusion, PPARβ/δ activation restored the lipid-induced endothelial dysfunction by up-regulation of CPT-1, thus reducing DAG accumulation and the subsequent PKC-mediated ROS production and eNOS inhibition.

  7. Isotetrandrine ameliorates tert-butyl hydroperoxide-induced oxidative stress through upregulation of heme oxygenase-1 expression

    PubMed Central

    Wang, Lidong; Ci, Xinxin; Lv, Hongming; Wang, Xiaosong

    2016-01-01

    1R, 1′S-isotetrandrine, a naturally occurring plant alkaloid found in Mahonia of Berberidaceae, possesses anti-inflammatory, antibacterial, and antiviral properties, but the antioxidative activity and mechanism action remain unclear. In this study, we demonstrated the antioxidative effect and mechanism of 1R, 1'S-isotetrandrine against tert-butyl hydroperoxide-induced oxidative damage in HepG2 cells. We found that 1R, 1′S-isotetrandrine suppressed cytotoxicity, reactive oxygen species generation, and glutathione depletion. Additionally, our study confirmed that 1R, 1′S-isotetrandrine significantly increased the antioxidant enzyme heme oxygenase-1 expression and nuclear translocation of factor-erythroid 2 p45-related factor 2 (Nrf2). Specifically, the nuclear translocation of Nrf2 induced by 1R, 1′S-isotetrandrine was associated with Nrf2 negative regulatory protein Keap1 inactivation and phosphorylation of both extracellular signal-regulated protein kinase and c-Jun NH2-terminal kinase. Preincubation with thiol-reducing agents reduced 1R, 1′S-isotetrandrine-induced heme oxygenase-1 expression, and treatment with either extracellular signal-regulated protein kinase or c-Jun NH2-terminal kinase inhibitors attenuated the levels of 1R, 1′S-isotetrandrine-induced Nrf2 activation and heme oxygenase-1 expression. Furthermore, the cytoprotective effect of 1R, 1′S-isotetrandrine was abolished by heme oxygenase-1, extracellular signal-regulated protein kinase, and c-Jun NH2-terminal kinase inhibitors. These results indicated that the 1R, 1′S-isotetrandrine ameliorated tert-butyl hydroperoxide-induced oxidative damage through upregulation of heme oxygenase-1 expression by the dissociation of Nrf2 from Nrf2-Keap1 complex via extracellular signal-regulated protein kinase and c-Jun NH2-terminal kinase activation and Keap1 inactivation. PMID:27190261

  8. Castration influences intestinal microflora and induces abdominal obesity in high-fat diet-fed mice

    PubMed Central

    Harada, Naoki; Hanaoka, Ryo; Horiuchi, Hiroko; Kitakaze, Tomoya; Mitani, Takakazu; Inui, Hiroshi; Yamaji, Ryoichi

    2016-01-01

    Late-onset hypogonadism (i.e. androgen deficiency) raises the risk for abdominal obesity in men. The mechanism for this obesity is unclear. Here, we demonstrated that hypogonadism after castration caused abdominal obesity in high-fat diet (HFD)-fed, but not in standard diet (SD)-fed, C57BL/6J mice. Furthermore, the phenotype was not induced in mice treated with antibiotics that disrupt the intestinal microflora. In HFD-fed mice, castration increased feed efficiency and decreased fecal weight per food intake. Castration also induced in an increase of visceral fat mass only in the absence of antibiotics in HFD-fed mice, whereas subcutaneous fat mass was increased by castration irrespective of antibiotics. Castration reduced the expression in the mesenteric fat of both adipose triglyceride lipase and hormone-sensitive lipase in HFD-fed mice, which was not observed in the presence of antibiotics. Castration decreased thigh muscle (i.e. quadriceps and hamstrings) mass, elevated fasting blood glucose levels, and increased liver triglyceride levels in a HFD-dependent manner, whereas these changes were not observed in castrated mice treated with antibiotics. The Firmicutes/Bacteroidetes ratio and Lactobacillus species increased in the feces of HFD-fed castrated mice. These results show that androgen (e.g. testosterone) deficiency can alter the intestinal microbiome and induce abdominal obesity in a diet-dependent manner. PMID:26961573

  9. Gomisin N inhibits adipogenesis and prevents high-fat diet-induced obesity

    PubMed Central

    Jang, Min-Kyung; Yun, Ye-Rang; Kim, Ji-Hyun; Park, Mi-Hee; Jung, Myeong Ho

    2017-01-01

    Gomisin N (GN) is a physiological lignan derived from Schisandra chinensis. In the present study, we investigated the inhibitory effects of GN on differentiation of 3T3-L1 preadipocytes and the anti-obesity effects of GN in high-fat diet (HFD)-induced obese mice. Incubation with GN significantly inhibited the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner. This inhibitory effect primarily occurred at an early adipogenic stage through impairment of mitotic clonal expansion (MCE) caused by cell cycle arrest at the G1/S phase transition. GN inhibited the extracellular signal-regulated kinase and phosphoinositide 3-kinase/protein kinase B signaling in the MCE process and activated AMP-activated protein kinase. Furthermore, GN downregulated CCAT/enhancer-binding protein β (C/EBPβ) and histone H3K9 demethylase JMJD2B during early stages of adipogenesis, and therefore repressed the expression of C/EBPβ-targeted cell cycle genes. In addition, GN also repressed the expression of histone H3K4 methyltransferase MLL4 and reduced PPARγ expression. Moreover, GN effectively lowered the final body weight, adipose tissue mass, and reduced the serum levels of glucose, total triglyceride, and cholesterol in the HFD-induced obese mice. GN also markedly reduced hepatic triglyceride level induced by HFD. Collectively, these findings suggest that GN has potential as a novel agent for the prevention and treatment of obesity. PMID:28067305

  10. Acute morphine induces matrix metalloproteinase-9 up-regulation in primary sensory neurons to mask opioid-induced analgesia in mice

    PubMed Central

    2012-01-01

    Background Despite decades of intense research efforts, actions of acute opioids are not fully understood. Increasing evidence suggests that in addition to well-documented antinociceptive effects opioids also produce paradoxical hyperalgesic and excitatory effects on neurons. However, most studies focus on the pronociceptive actions of chronic opioid exposure. Matrix metalloproteinase 9 (MMP-9) plays an important role in neuroinflammation and neuropathic pain development. We examined MMP-9 expression and localization in dorsal root ganglia (DRGs) after acute morphine treatment and, furthermore, the role of MMP-9 in modulating acute morphine-induced analgesia and hyperalgesia in mice. Results Subcutaneous morphine induced a marked up-regulation of MMP-9 protein in DRGs but not spinal cords. Morphine also increased MMP-9 activity and mRNA expression in DRGs. MMP-9 up-regulation peaked at 2 h but returned to the baseline after 24 h. In DRG tissue sections, MMP-9 is expressed in small and medium-sized neurons that co-express mu opioid receptors (MOR). In DRG cultures, MOR agonists morphine, DAMGO, and remifentanil each increased MMP-9 expression in neurons, whereas the opioid receptor antagonist naloxone and the MOR-selective antagonist D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) suppressed morphine-induced MMP-9 expression. Notably, subcutaneous morphine-induced analgesia was enhanced and prolonged in Mmp9 knockout mice and also potentiated in wild-type mice receiving intrathecal injection of MMP-9 inhibitors. Consistently, intrathecal injection of specific siRNA targeting MMP-9 reduced MMP-9 expression in DRGs and enhanced and prolonged morphine analgesia. Subcutaneous morphine also produced heat hyperalgesia at 24 h, but this opioid-induced hyperalgesia was not enhanced after MMP-9 deletion or inhibition. Conclusions Transient MMP-9 up-regulation in DRG neurons can mask opioid analgesia, without modulating opioid-induced hyperalgesia. Distinct molecular

  11. GAP-43 expression is upregulated in retinal ganglion cells after ischemia/reperfusion-induced damage.

    PubMed

    Dijk, Frederike; Bergen, Arthur A B; Kamphuis, Willem

    2007-05-01

    In response to injury, the adult mammalian retina shows signs of structural remodeling, possibly in an attempt to preserve or regain some of its functional neural connections. In order to study the mechanisms involved in injury-induced plasticity, we have studied changes in growth associated protein 43 (GAP-43) after retinal ischemia/reperfusion in the rat. GAP-43 is a marker for neuronal remodeling and is involved in synapse formation. Ischemic injury of the rat retina was induced by 60 min of ischemia followed by reperfusion times varying from 2h up to 4 weeks. GAP-43 mRNA levels were significantly increased between 12h and 72 h reperfusion with a peak around 24h. GAP-43 specific antibodies showed that the total amount of GAP-43 labeling in the inner plexiform layer was diminished after 12h of reperfusion by approximately 35% and remained at this level up to 1 week postischemia despite the reduction in thickness of this layer during this period resulting from the ischemia-induced cell loss. At 2 and 4 weeks reperfusion, the amount of labeling was reduced by 70%, simultaneously with a decrease of GAP-43 transcript level. Between 72 h up to 2 weeks postischemia, the induction of intense GAP-43 labeling was observed in NeuN- and beta-tubulin-positive ganglion cell somata and in horizontally and vertically oriented processes in the inner plexiform layer. Ischemia also induced GAP-43 expression in some GFAP-positive Müller cells. Double-labeling showed that in controls and after ischemia GAP-43 was expressed by some amacrine cells of the glycinergic (glycine transporter 1), calretinin-positive, and dopaminergic (tyrosine hydroxylase) subpopulations. No increase of GAP-43 expression levels was found in these amacrine cells. The results demonstrate that ganglion cells show an elevated expression of GAP-43 after ischemia-inflicted damage. These findings suggest a temporal window during which ganglion cells may remodel their neuronal network in the damaged retina.

  12. Protective effect of resveratrol on spermatozoa function in male infertility induced by excess weight and obesity

    PubMed Central

    Cui, Xiangrong; Jing, Xuan; Wu, Xueqing; Yan, Meiqin

    2016-01-01

    Male infertility is a complex, multifactorial and polygenic disease that contributes to ~50% cases of infertility. Previous studies have demonstrated that excess weight and obesity factors serve an important role in the development of male infertility. An increasing number of studies have reported that resveratrol may regulate the response of cells to specific stimuli that induce cell injury, as well as decrease germ cell apoptosis in mice or rats. In the present study, the semen quality and serum sex hormone levels were evaluated in 324 men, which included 73 underweight, 82 normal weight, 95 overweight and 74 obese men. All patients were referred to The Reproductive Medicine Center of Shanxi Women and Infants Hospital (Taiyuan, China) between January 2013 and January 2015. The aim of the present study was to investigate the effects of resveratrol treatment on the motility, plasma zinc concentration and acrosin activity of sperm from obese males. The sperm concentration, normal sperm morphology, semen volumes, DNA fragmentation rates and testosterone levels in men from the overweight and obese groups were markedly decreased when compared with men in the normal weight group. In addition, the progressive motility, seminal plasma zinc concentration and spermatozoa acrosin activity were notably decreased in the obese group compared with the normal weight group. However, estradiol levels were significantly increased in the overweight, obese and underweight groups compared with the normal weight group. Notably, semen samples from obese males with astenospermia treated with 0–100 µmol/l resveratrol for 30 min demonstrated varying degrees of improvement in sperm motility. When these semen samples were treated with 30 µmol/l resveratrol, sperm motility improved when compared to other doses of resveratrol. Therefore, 30 µmol/l resveratrol was selected for further experiments. Upon treatment of semen samples with resveratrol (30 µmol/l) for 30 min, the seminal plasma

  13. Protective effect of resveratrol on spermatozoa function in male infertility induced by excess weight and obesity.

    PubMed

    Cui, Xiangrong; Jing, Xuan; Wu, Xueqing; Yan, Meiqin

    2016-11-01

    Male infertility is a complex, multifactorial and polygenic disease that contributes to ~50% cases of infertility. Previous studies have demonstrated that excess weight and obesity factors serve an important role in the development of male infertility. An increasing number of studies have reported that resveratrol may regulate the response of cells to specific stimuli that induce cell injury, as well as decrease germ cell apoptosis in mice or rats. In the present study, the semen quality and serum sex hormone levels were evaluated in 324 men, which included 73 underweight, 82 normal weight, 95 overweight and 74 obese men. All patients were referred to The Reproductive Medicine Center of Shanxi Women and Infants Hospital (Taiyuan, China) between January 2013 and January 2015. The aim of the present study was to investigate the effects of resveratrol treatment on the motility, plasma zinc concentration and acrosin activity of sperm from obese males. The sperm concentration, normal sperm morphology, semen volumes, DNA fragmentation rates and testosterone levels in men from the overweight and obese groups were markedly decreased when compared with men in the normal weight group. In addition, the progressive motility, seminal plasma zinc concentration and spermatozoa acrosin activity were notably decreased in the obese group compared with the normal weight group. However, estradiol levels were significantly increased in the overweight, obese and underweight groups compared with the normal weight group. Notably, semen samples from obese males with astenospermia treated with 0‑100 µmol/l resveratrol for 30 min demonstrated varying degrees of improvement in sperm motility. When these semen samples were treated with 30 µmol/l resveratrol, sperm motility improved when compared to other doses of resveratrol. Therefore, 30 µmol/l resveratrol was selected for further experiments. Upon treatment of semen samples with resveratrol (30 µmol/l) for 30 min, the seminal

  14. Exaggerated haemodynamic and neural responses to involuntary contractions induced by whole-body vibration in normotensive obese versus lean women.

    PubMed

    Dipla, Konstantina; Kousoula, Dimitra; Zafeiridis, Andreas; Karatrantou, Konstantina; Nikolaidis, Michalis G; Kyparos, Antonios; Gerodimos, Vassilis; Vrabas, Ioannis S

    2016-06-01

    What is the central question of this study? In obesity, the exaggerated blood pressure response to voluntary exercise is linked to hypertension, yet the mechanisms are not fully elucidated. We examined whether involuntary contractions elicit greater haemodynamic responses and altered neural control of blood pressure in normotensive obese versus lean women. What is the main finding and its importance? During involuntary contractions induced by whole-body vibration, there were augmented blood pressure and spontaneous baroreflex responses in obese compared with lean women. This finding is suggestive of an overactive mechanoreflex in the exercise-induced hypertensive response in obesity. Passive contractions did not elicit differential heart rate responses in obese compared with lean women, implying other mechanisms for the blunted heart rate response reported during voluntary exercise in obesity. In obesity, the exaggerated blood pressure (BP) response to exercise is linked to hypertension, yet the mechanisms are not fully elucidated. In this study, we examined whether involuntary mechanical oscillations, induced by whole-body vibration (WBV), elicit greater haemodynamic responses and altered neural control of BP in obese versus lean women. Twenty-two normotensive, premenopausal women (12 lean and 10 obese) randomly underwent a passive WBV (25 Hz) and a control protocol (similar posture without WVB). Beat-by-beat BP, heart rate, stroke volume, systemic vascular resistance, cardiac output, parasympathetic output (evaluated by heart rate variability) and spontaneous baroreceptor sensitivity (sBRS) were assessed. We found that during WBV, obese women exhibited an augmented systolic BP response compared with lean women that was correlated with body fat percentage (r = 0.77; P < 0.05). The exaggerated BP rise was driven mainly by the greater increase in cardiac output index in obese versus lean women, associated with a greater stroke volume index in obese women

  15. Diet-induced obesity in rats leads to a decrease in sperm motility

    PubMed Central

    2011-01-01

    Background Obesity is rapidly becoming a worldwide epidemic that affects children and adults. Some studies have shown a relationship between obesity and infertility, but until now it remains controversial. Thus, the aim of the present study was to investigate the effect of high-fat diet-induced obesity on male reproductive parameters. Methods In a first experiment, male Wistar rats were fed a high-fat diet (HFD) or standard chow (SD) for 15, 30 or 45 weeks, after which they were evaluated by adiposity index, serum leptin levels, reproductive organ weights and sperm counts. In a second experiment, rats received HFD or SD only for 15 weeks, long enough to cause obesity. Sexual hormones and sexual behavior were evaluated in these animals, as well as fertility after natural mating. Another group of rats was submitted to motility analysis and fertility evaluation after in utero insemination. Results After 15, 30 or 45 weeks, HFD-fed animals presented significant increases in obesity index and serum leptin levels. Reproductive organ weights and sperm counts in the testis and epididymis were similar between the two groups at all timepoints studied. Sexual behavior was not altered by the diet regimen, and HFD fertility after natural mating was also similar to SD-fed animals. Intergroup testosterone levels were also comparable, but estradiol levels were increased in HFD rats. Furthermore, sperm quality was reduced in HFD animals as evidenced by their decreased percentage of sperm with progressive movement. This altered motility parameter was followed by a trend toward reduction in fertility potential after artificial in utero insemination. Conclusions The results reported herein showed that obesity can affect sperm quality, by reducing sperm motility, without affecting other sperm parameters. The low sperm quality caused a slight reduction in fertility potential, showing that obesity may lead to impairment in male fertility. PMID:21396114

  16. Activation of the aryl hydrocarbon receptor induces hepatic steatosis via the upregulation of fatty acid transport.

    PubMed

    Kawano, Yuki; Nishiumi, Shin; Tanaka, Shinwa; Nobutani, Kentaro; Miki, Akira; Yano, Yoshihiko; Seo, Yasushi; Kutsumi, Hiromu; Ashida, Hitoshi; Azuma, Takeshi; Yoshida, Masaru

    2010-12-15

    The aryl hydrocarbon receptor (AHR) is a basic helix-loop-helix/Per-ARNT-Sim domain transcription factor, which is activated by various xenobiotic ligands. AHR is known to be abundant in liver tissue and to be associated with hepatic steatosis. However, it has not yet been elucidated how the activation of AHR promotes hepatic steatosis. The aim of this study is to clarify the role of AHR in hepatic steatosis. The intraperitoneal injection of 3-methylcholanthrene (3MC), a potent AHR ligand, into C57BL/6J mice significantly increased the levels of triglycerides and six long-chain monounsaturated fatty acids in the livers of mice, resulting in hepatic microvesicular steatosis. 3MC significantly enhanced the expression level of fatty acid translocase (FAT), a factor regulating the uptake of long-chain fatty acids into hepatocytes, in the liver. In an in vitro experiment using human hepatoma HepG2 cells, 3MC increased the expression level of FAT, and the downregulation of AHR by AHR siRNA led to the suppression of 3MC-induced FAT expression. In addition, the mRNA level of peroxisome proliferator-activated receptor (PPAR) α, an upstream factor of FAT, was increased in the livers of 3MC-treated mice. Taking together, AHR activation induces hepatic microvesicular steatosis by increasing the expression level of FAT.

  17. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    SciTech Connect

    Ganesan, Shanthi Nteeba, Jackson Keating, Aileen F.

    2014-12-01

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity.

  18. Obesity-induced endoplasmic reticulum stress suppresses nuclear factor-Y expression.

    PubMed

    Liu, Yulan; Zhang, Yuwei; Zhang, Yanjie; Zhang, Jinlong; Liu, Yin; Feng, Peiqun; Su, Zhiguang

    2017-02-01

    Nuclear transcription factor Y (NF-Y) is an evolutionarily conserved transcription factor composed of three subunits, NF-YA, NF-YB, and NF-YC. NF-Y plays crucial roles in pre-adipocyte maintenance and/or commitment to adipogenesis. NF-YA dysfunction in adipocyte resulted in an age-dependent progressive loss of adipose tissue associated with metabolic complications. Endoplasmic reticulum (ER) stress has emerged as an important mediator in the pathogenesis of obesity. However, it is not known if NF-YA is involved in the ER stress-mediated pathogenesis of obesity. We first examined the effects of ER stress on the NF-YA expression in cultured 3T3-L1 adipocytes; then in ob/ob genetic obesity mice, we tested the effect of chemical chaperones alleviating ER stress on the expression levels of NF-YA. Subsequently, we inhibited the new mRNA synthesis using actinomycin D in 3T3-L1 cells to explore the mechanism modulating NF-YA expression. Finally, we evaluated the involvement of PPARg in the regulation of NF-YA expression by ER stress. We demonstrated that both obesity- and chemical chaperone -induced ER stress suppressed NF-YA expression and alleviation of ER stress by chemical chaperone could recover NF-YA expression in ob/ob mice. Moreover, we showed that ER stress suppressed NF-YA mRNA transcription through the involvement of peroxisome proliferator-activated receptor gamma (PPARg). Activation of PPARg ameliorates the ER stress-induced NF-YA suppression. Our findings may point to a possible role of NF-YA in stress conditions that occur in chronic obesity, ER stress might be involved in the pathogenesis of obesity through NF-YA depletion.

  19. Adiponectin: a biomarker of obesity-induced insulin resistance in adipose tissue and beyond.

    PubMed

    Lu, Jin-Ying; Huang, Kuo-Chin; Chang, Lin-Chau; Huang, Ying-Shing; Chi, Yu-Chiao; Su, Ta-Chan; Chen, Chi-Ling; Yang, Wei-Shiung

    2008-09-01

    Adiponectin is one of the most thoroughly studied adipocytokines. Low plasma levels of adiponectin are found to associate with obesity, metabolic syndrome, diabetes and many other human diseases. From animal experiments and human studies, adiponectin has been shown to be a key regulator of insulin sensitivity. In this article, we review the evidence and propose that hypo-adiponectinemia is not a major cause of obesity. Instead, it is the result of obesity-induced insulin resistance in the adipose tissue. Hypo-adiponectinemia then mediates the metabolic effects of obesity on the other peripheral tissues, such as liver and skeletal muscle and may also exert some direct effects on end-organ damage. We propose that deciphering the molecular details governing the adiponectin gene expression and protein secretion will lead us to more comprehensive understanding of the mechanisms of insulin resistance in the adipose tissue and provide us new avenues for the therapeutic intervention of obesity and insulin resistance-related human disorders.

  20. Metabolomic profiling of urinary changes in mice with monosodium glutamate-induced obesity.

    PubMed

    Pelantová, Helena; Bártová, Simona; Anýž, Jiří; Holubová, Martina; Železná, Blanka; Maletínská, Lenka; Novák, Daniel; Lacinová, Zdena; Šulc, Miroslav; Haluzík, Martin; Kuzma, Marek

    2016-01-01

    Obesity with related complications represents a widespread health problem. The etiopathogenesis of obesity is often studied using numerous rodent models. The mouse model of monosodium glutamate (MSG)-induced obesity was exploited as a model of obesity combined with insulin resistance. The aim of this work was to characterize the metabolic status of MSG mice by NMR-based metabolomics in combination with relevant biochemical and hormonal parameters. NMR analysis of urine at 2, 6, and 9 months revealed altered metabolism of nicotinamide and polyamines, attenuated excretion of major urinary proteins, increased levels of phenylacetylglycine and allantoin, and decreased concentrations of methylamine in urine of MSG-treated mice. Altered levels of creatine, citrate, succinate, and acetate were observed at 2 months of age and approached the values of control mice with aging. The development of obesity and insulin resistance in 6-month-old MSG mice was also accompanied by decreased mRNA expressions of adiponectin, lipogenetic and lipolytic enzymes and peroxisome proliferator-activated receptor-gamma in fat while mRNA expressions of lipogenetic enzymes in the liver were enhanced. At the age of 9 months, biochemical parameters of MSG mice were normalized to the values of the controls. This fact pointed to a limited predictive value of biochemical data up to age of 6 months as NMR metabolomics confirmed altered urine metabolic composition even at 9 months.

  1. Leptin resistance and diet-induced obesity: central and peripheral actions of leptin.

    PubMed

    Sáinz, Neira; Barrenetxe, Jaione; Moreno-Aliaga, María J; Martínez, José Alfredo

    2015-01-01

    Obesity is a chronic disease that represents one of the most serious global health burdens associated to an excess of body fat resulting from an imbalance between energy intake and expenditure, which is regulated by environmental and genetic interactions. The adipose-derived hormone leptin acts via a specific receptor in the brain to regulate energy balance and body weight, although this protein can also elicit a myriad of actions in peripheral tissues. Obese individuals, rather than be leptin deficient, have in most cases, high levels of circulating leptin. The failure of these high levels to control body weight suggests the presence of a resistance process to the hormone that could be partly responsible of disturbances on body weight regulation. Furthermore, leptin resistance can impair physiological peripheral functions of leptin such as lipid and carbohydrate metabolism and nutrient intestinal utilization. The present document summarizes those findings regarding leptin resistance development and the role of this hormone in the development and maintenance of an obese state. Thus, we focused on the effect of the impaired leptin action on adipose tissue, liver, skeletal muscle and intestinal function and the accompanying relationships with diet-induced obesity. The involvement of some inflammatory mediators implicated in the development of obesity and their roles in leptin resistance development are also discussed.

  2. Anti-obesity effects of Arctii Fructus (Arctium lappa) in white/brown adipocytes and high-fat diet-induced obese mice.

    PubMed

    Han, Yo-Han; Kee, Ji-Ye; Kim, Dae-Seung; Park, Jinbong; Jeong, Mi-Young; Mun, Jung-Geon; Park, Sung-Joo; Lee, Jong-Hyun; Um, Jae-Young; Hong, Seung-Heon

    2016-12-07

    Arctii Fructus is traditionally used in oriental pharmacies as an anti-inflammatory medicine. Although several studies have shown its anti-inflammatory effects, there have been no reports on its use in obesity related studies. In this study, the anti-obesity effect of Arctii Fructus was investigated in high-fat diet (HFD)-induced obese mice, and the effect was confirmed in white and primary cultured brown adipocytes. Arctii Fructus inhibited weight gain and reduced the mass of white adipose tissue in HFD-induced obese mice. Serum levels of triglyceride and LDL-cholesterol were reduced, and HDL-cholesterol was increased in the Arctii Fructus treated group. In 3T3-L1 cells, a water extract (WAF) and 70% EtOH extract (EtAF) of Arctii Fructus significantly inhibited adipogenesis and suppressed the expression of proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha. In particular, EtAF activated the phosphorylation of AMP-activated protein kinase. On the other hand, uncoupling protein 1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha, known as brown adipocytes specific genes, were increased in primary cultured brown adipocytes by WAF and EtAF. This study shows that Arctii Fructus prevents the development of obesity through the inhibition of white adipocyte differentiation and activation of brown adipocyte differentiation which suggests that Arctii Fructus could be an effective therapeutic for treating or preventing obesity.

  3. NADPH oxidase gp91phox contributes to RANKL-induced osteoclast differentiation by upregulating NFATc1

    PubMed Central

    Kang, In Soon; Kim, Chaekyun

    2016-01-01

    Bone-marrow derived monocyte-macrophages (BMMs) differentiate into osteoclasts by M-CSF along subsequent RANKL stimulation possibly in collaboration with many other unknown cytokines released by pre- or mature osteoblasts. The differentiation process requires receptor activator of nuclear factor kappa-B ligand (RANKL)/RANK signaling and reactive oxygen species (ROS) such as superoxide anion (O2•−). Gp91phox, a plasma membrane subunit of NADPH oxidase (Nox), is constitutively expressed in BMMs and plays a major role in superoxide anion production. In this study, we found that mice deficient in gp91phox (gp91phox−/−) showed defects in osteoclast differentiation. Femurs of these mice produced osteoclasts at about 70% of the levels seen in femurs from wild-type mice, and accordingly exhibited excessive bone density. This abnormal bone growth in the femurs of gp91phox−/− mice resulted from impaired osteoclast differentiation. In addition, gp91phox−/− mice were defective for RANKL-induced expression of nuclear factor of activated T cells c1 (NFATc1). However, H2O2 treatment compensated for gp91phox deficiency in BMMs, almost completely rescuing osteoclast differentiation. Treating wild-type BMMs with antioxidants and superoxide inhibitors resulted in a differentiation defect resembling the phenotype of gp91phox−/− BMMs. Therefore, our results demonstrate that gp91phox-derived superoxide is important for promoting efficient osteoclast differentiation by inducing NFATc1 as a downstream signaling mediator of RANK. PMID:27897222

  4. L-Carnitine intake prevents irregular feeding-induced obesity and lipid metabolism disorder.

    PubMed

    Wu, Tao; Guo, Anqi; Shu, Qingyu; Qi, Yangjian; Kong, Ying; Sun, Zhiping; Sun, Shumin; Fu, Zhengwei

    2015-01-10

    L-Carnitine supplementation has been used to reduce obesity caused by high-fat diet, which is beneficial for lowering blood and hepatic lipid levels, and for ameliorating fatty liver. However, whether l-carnitine may affect irregular feeding-induced obesity and lipid metabolism disorder is still largely unknown. In the present study, we developed a time-delayed pattern of eating, and investigated the effects of l-carnitine on the irregular eating induced adiposity in mice. After an experimental period of 8 weeks with l-carnitine supplementation, l-carnitine significantly inhibited body weight increase and epididymal fat weight gain induced by the time-delayed feeding. In addition, l-carnitine administration decreased levels of serum alanine aminotransferase (GPT), glutamic oxalacetic transaminase (GOT) and triglyceride (TG), which were significantly elevated by the irregular feeding. Moreover, mice supplemented with l-carnitine did not display glucose intolerance-associated hallmarks, which were found in the irregular feeding-induced obesity. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that l-carnitine counteracted the negative alterations of lipid metabolic gene expression (fatty acid synthase, 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, cholesterol 7α-hydroxylase, carnitine/acylcarnitine translocase) in the liver and fat of mice caused by the irregular feeding. Therefore, our results suggest that the time-delayed pattern of eating can induce adiposity and lipid metabolic disorders, while l-carnitine supplementation might prevent these negative symptoms.

  5. Paroxetine alleviates rat limb post-ischemia induced allodynia through GRK2 upregulation in superior cervical ganglia.

    PubMed

    Tang, Jun; Dong, Jing; Yang, Li; Gao, Lingqi; Zheng, Jijian

    2015-01-01

    Long-lasting neuroplastic changes induced by transient decrease in G protein-coupled receptor kinase 2 (GRK2) in nociceptors enhances and prolongs inflammatory hyperalgesia. Here, we investigated the effects of paroxetine (a selective serotonin reuptake inhibitor and GRK2 inhibitor) on GRK2 expression in superior cervical ganglion (SCG) in a rat model of complex regional pain syndrome type I (CRPS-I). After ischemia-reperfusion (I/R) injury, the ipsilateral 50% paw withdrawal thresholds (PWTs) to mechanical stimuli and the expression levels of GRK2 protein and mRNA in the ipsilateral SCGs all decreased significantly; the ipsilateral cold allodynia scores increased significantly. No significant differences were found in the contralateral side except GRK2 mRNA reduced significantly at day 2-day 9 after I/R injury, but still higher than those in ipsilateral SCGs. After paroxetine administration, the ipsilateral 50% PWTs at day 2, 7, 14, and 21 were significantly higher than those in control group; The GRK2 protein and mRNA levels in ipsilateral SCGs were also significantly up-regulated after day1; The ipsilateral cold allodynia scores were significantly reduced after day7. No significant differences were found in the contralateral 50% PWTs, cold allodynia scores, and GRK2 protein level except GRK2 mRNA levels increased significantly at day1-day7 after paroxetine administration. Therefore, a transient decrease of GRK2 expression in SCG neurons might be involved in the development and maintenance of allodynia in CRPS-I and paroxetine might alleviate this allodynia through GRK2 protein upregulation in SCGs.

  6. Paroxetine alleviates rat limb post-ischemia induced allodynia through GRK2 upregulation in superior cervical ganglia

    PubMed Central

    Tang, Jun; Dong, Jing; Yang, Li; Gao, Lingqi; Zheng, Jijian

    2015-01-01

    Long-lasting neuroplastic changes induced by transient decrease in G protein-coupled receptor kinase 2 (GRK2) in nociceptors enhances and prolongs inflammatory hyperalgesia. Here, we investigated the effects of paroxetine (a selective serotonin reuptake inhibitor and GRK2 inhibitor) on GRK2 expression in superior cervical ganglion (SCG) in a rat model of complex regional pain syndrome type I (CRPS-I). After ischemia-reperfusion (I/R) injury, the ipsilateral 50% paw withdrawal thresholds (PWTs) to mechanical stimuli and the expression levels of GRK2 protein and mRNA in the ipsilateral SCGs all decreased significantly; the ipsilateral cold allodynia scores increased significantly. No significant differences were found in the contralateral side except GRK2 mRNA reduced significantly at day 2-day 9 after I/R injury, but still higher than those in ipsilateral SCGs. After paroxetine administration, the ipsilateral 50% PWTs at day 2, 7, 14, and 21 were significantly higher than those in control group; The GRK2 protein and mRNA levels in ipsilateral SCGs were also significantly up-regulated after day1; The ipsilateral cold allodynia scores were significantly reduced after day7. No significant differences were found in the contralateral 50% PWTs, cold allodynia scores, and GRK2 protein level except GRK2 mRNA levels increased significantly at day1-day7 after paroxetine administration. Therefore, a transient decrease of GRK2 expression in SCG neurons might be involved in the development and maintenance of allodynia in CRPS-I and paroxetine might alleviate this allodynia through GRK2 protein upregulation in SCGs. PMID:25932137

  7. Early upregulation of myocardial CXCR4 expression is critical for dimethyloxalylglycine-induced cardiac improvement in acute myocardial infarction.

    PubMed

    Mayorga, Mari; Kiedrowski, Matthew; Shamhart, Patricia; Forudi, Farhad; Weber, Kristal; Chilian, William M; Penn, Marc S; Dong, Feng

    2016-01-01

    The stromal cell-derived factor-1 (SDF-1):CXCR4 is important in myocardial repair. In this study we tested the hypothesis that early upregulation of cardiomyocyte CXCR4 (CM-CXCR4) at a time of high myocardial SDF-1 expression could be a strategy to engage the SDF-1:CXCR4 axis and improve cardiac repair. The effects of the hypoxia inducible factor (HIF) hydroxylase inhibitor dimethyloxalylglycine (DMOG) on CXCR4 expression was tested on H9c2 cells. In mice a myocardial infarction (MI) was produced in CM-CXCR4 null and wild-type controls. Mice were randomized to receive injection of DMOG (DMOG group) or saline (Saline group) into the border zone after MI. Protein and mRNA expression of CM-CXCR4 were quantified. Echocardiography was used to assess cardiac function. During hypoxia, DMOG treatment increased CXCR4 expression of H9c2 cells by 29 and 42% at 15 and 24 h, respectively. In vivo DMOG treatment increased CM-CXCR4 expression at 15 h post-MI in control mice but not in CM-CXCR4 null mice. DMOG resulted in increased ejection fraction in control mice but not in CM-CXCR4 null mice 21 days after MI. Consistent with greater cardiomyocyte survival with DMOG treatment, we observed a significant increase in cardiac myosin-positive area within the infarct zone after DMOG treatment in control mice, but no increase in CM-CXCR4 null mice. Inhibition of cardiomyocyte death in MI through the stabilization of HIF-1α requires downstream CM-CXCR4 expression. These data suggest that engagement of the SDF-1:CXCR4 axis through the early upregulation of CM-CXCR4 is a strategy for improving cardiac repair after MI.

  8. Supplementation of a Fermented Soybean Extract Reduces Body Mass and Prevents Obesity in High Fat Diet-Induced C57BL/6J Obese Mice

    PubMed Central

    Lee, Jae Yeon; Aravinthan, Adithan; Park, Young Shik; Hwang, Kyo Yeol; Seong, Su-Il; Hwang, Kwontack

    2016-01-01

    Obesity is a growing health problem that many countries face, mostly due to the consumption of a Westernized diet. In this present study we observed the effects of a soybean extract fermented by Bacillus subtilis MORI (BTD-1) containing 1-deoxynojirimycin against high fat diet-induced obesity. The results obtained from this study indicated that BTD-1 reduced body weight, regulated hepatic lipid content and adipose tissue, and also affected liver antioxidant enzymes and glucose metabolism. These results suggest that administration of BTD-1 affects obesity by inhibiting hyperglycemia and free radical-mediated stress; it also reduces lipid accumulation. Therefore, BTD-1 may be potentially useful for the prevention of obesity and its related secondary complications. PMID:27752494

  9. The upregulation of pro-inflammatory cytokines in the rabbit uterus under the lipopolysaccaride-induced reversible immunoresponse state.

    PubMed

    Liu, S J; Shi, Y; Liu, C; Zhang, M; Zuo, Z C; Zeng, C J; Zhou, G B; Xian, H; Song, T Z

    2017-01-01

    The reproductive organs are more likely to develop gram-negative bacterial infection than other internal organs because of direct access to the body surface. The objective of this study was (1) to provide a suitable intravenous injection dose of lipopolysaccharides (LPS) instead of gram-negative bacterial infection in order to induce a reversible immunoresponse state and (2) to examine the expression levels of pro-inflammatory cytokines in the uterus of rabbits while in an immunoresponse state. Two series of experiments were performed to accomplish these objectives. In the first series, 20 healthy New Zealand White female rabbits were divided into 5 homogeneous groups (n=4), and intravenously injected with 0, 0.5, 1, 2, or 4mg/kg body weight (BW) of LPS derived from Escherichia coli dissolved in 2ml of sterile saline (LPS carrier). The control group received only saline. The concentrations of IL-1β, IL-6, and TNF-α in serum and the white blood cell count changed with time after LPS stimulation, and certain doses of LPS led to the death of some rabbits. The results suggested that a dose of 0.5mg/kg of LPS induced a reversible immunoresponse state. In the second series, 4 rabbits were not injected (0h), 16 rabbits were injected with 0.5mg/kg LPS, and 16 rabbits in the control group were injected with 2ml of sterile saline. Tissues of the uterine horn, uterine body, and cervix from the 36 rabbits were collected at 0, 1.5, 3, 6, and 12h (n=4) postinjection for examination of the expression levels of IL-1β, IL-6, and TNF-α by quantitative real-time PCR (qRT-PCR). The results suggested that 0.5mg/kg of LPS upregulated the expression levels of IL-1β, IL-6 and TNF-α in the uterine body and uterine horn, and IL-6 in the cervix. In conclusion, the expression levels of IL-1β, IL-6 and TNF-α were upregulated in the uterus of rabbits under the reversible immunoresponse state induced by 0.5mg/kg of LPS-injection.

  10. Resolvin D1 reduces deterioration of tight junction proteins by upregulating HO-1 in LPS-induced mice.

    PubMed

    Xie, Wanli; Wang, Huiqing; Wang, Lei; Yao, Chengye; Yuan, Ruixia; Wu, Qingping

    2013-09-01

    Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) is characterized by increased pulmonary permeability with high mortality. Resolvin D1 (RvD1), which has potent anti-inflammatory and pro-resolving activity, can attenuate pulmonary edema in the animal model of ALI. However, the mechanism underlying the protection of RvD1 on pulmonary edema is still unknown. Here we explore the effects and mechanism of RvD1 on the disruption of tight junction protein that results in the permeability edema in a model of lipopolysaccharide (LPS)-induced ALI. The severity of pulmonary edema was assessed by wet-to-dry rate and Evans blue infiltration; expressions of tight junction (TJ) proteins occludin and zona occludin-1 (ZO-1) were examined by immunofluorescence staining and western blot; mRNA in lung tissue was studied by real time-PCR; the TUNEL kit was performed for the detection of apoptosis of pulmonary barrier. Twenty-four hours after LPS inhalation by mice, wet-to-dry rate and Evans blue infiltration indicated that pretreatment with RvD1 relieved the pulmonary edema and pulmonary capillary permeability. Moreover, RvD1 attenuated the LPS-induced deterioration of TJ protein ZO-1 and occludin significantly. And we found that RvD1 increased heme oxygenase-1 (HO-1) expression contributed to the protection on the deterioration of TJs. In addition, we found that RvD1 could reduce pulmonary cellular apoptosis in LPS-induced mice. In conclusion, RvD1 possesses the ability that relieves the pulmonary edema and restores pulmonary capillary permeability and reduces disruption of TJs in LPS-induced ALI of mice, at least in part, by upregulating HO-1 expression.

  11. Lansoprazole induces mucosal protection through gastrin receptor-dependent up-regulation of cyclooxygenase-2 in rats.

    PubMed

    Tsuji, Shingo; Sun, Wei-Hao; Tsujii, Masahiko; Kawai, Naoki; Kimura, Arata; Kakiuchi, Yoshimi; Yasumaru, Shoichi; Komori, Masato; Murata, Hiroaki; Sasaki, Yutaka; Kawano, Sunao; Hori, Masatsugu

    2002-12-01

    Proton pump inhibitors (PPIs) are antiulcer agents that have both gastric antisecretory and mucosal protective actions. The mechanisms of PPI-induced gastric mucosal protection are not known. The present study was designed to examine the mechanism for lansoprazole-induced gastric mucosal protection in rats. Rats were given 0.5, 5, and 50 mg/kg/day lansoprazole alone or both lansoprazole (50 mg/kg/day) and a specific gastrin receptor antagonist 3R-1-(2,2-diethoxyethyl)-((4-methylphenyl)amino-carbonyl methyl)-3-((4-methylphenyl)ureidoindoline-2- one) (AG-041R) (3, 10, and 30 mg/kg/day) for 14 days. Serum gastrin concentrations were measured. The expression of cyclooxygenases (COX-1 and COX-2) in the gastric mucosa was analyzed using Western blotting and immunohistochemical staining. Another series of rats was used to examine the 1) levels of prostaglandin (PG) E2 in gastric mucosa, 2) influences of the drugs on gastric damage caused by absolute ethanol, and 3) effects of a COX-2-specific inhibitor on PGE2 in the gastric mucosa and the mucosal protection afforded by lansoprazole. Lansoprazole dose dependently increased the serum gastrin concentration and enhanced the mucosal expression of COX-2 but not that of COX-1. Lansoprazole increased gastric mucosal PGE2 and reduced gastric damage caused by ethanol. Concomitant administration of AG-041R abolished the lansoprazole-induced COX-2 expression, and increased mucosal PGE2 and mucosal protection. A specific COX-2 inhibitor blocked the lansoprazole-induced increase in mucosal PGE2 and mucosal protection. Activation of gastrin receptors by endogenous gastrin has a pivotal role in the effects of lansoprazole on COX-2 up-regulation and mucosal protection in the rat stomach.

  12. Botanical Drug Puerarin Attenuates 6-Hydroxydopamine (6-OHDA)-Induced Neurotoxicity via Upregulating Mitochondrial Enzyme Arginase-2.

    PubMed

    Zhao, Jia; Cheng, Yuanyuan; Yang, Chuanbin; Lau, Sam; Lao, Lixing; Shuai, Bo; Cai, Jing; Rong, Jianhui

    2016-05-01

    Inhibition of nitric oxide synthases (NOSs) shows promise to halt the progression of neurodegenerative diseases. The present study was designed to explore whether botanical isoflavone puerarin could attenuate nitric oxide (NO)-mediated neurotoxicity via modulating the enzymes in the L-arginine-NO pathway. Neurotoxin 6-hydroxydopamine (6-OHDA) is well known to induce neurodegeneration via a NO-dependent mechanism. We first validated that puerarin protected rat dopamingeric PC12 cells against 6-OHDA-induced neurotoxicity in a concentration-dependent manner. We subsequently profiled the cellular responses to puerarin by a proteomic response fingerprinting approach. A total of 16 protein spots with >1.5-fold change of intensity were selected and identified by mass spectrometry. As one of puerarin-upregulated proteins, mitochondrial arginase-2 hydrolyzes L-arginine to L-ornithine, thereby competing with neuronal NOS for substrate L-arginine in mitochondria. Thus, we hypothesize that puerain may attenuate nitric oxide (NO)-mediated mitochondrial injury via increasing arginase-2 expression. Western blot and reverse transcription polymerase chain reaction (RT-PCR) analyses confirmed that puerarin increased arginase-2 expression in a concentration- and time-dependent manner. Accordingly, puerarin suppressed 6-OHDA-induced NO production and neurotoxicity in PC12 cells and primary rat midbrain neurons. Arginase inhibitor BEC diminished the effect of puerarin on 6-OHDA-induced NO production and neurotoxicity. The activation of arginase-2 by puerarin represents an endogenous mechanism for specific control of NO-mediated mitochondrial damage. Thus, puerarin is a useful lead for suppressing NO-mediated neurotoxicity in neurodegenerative diseases. Graphical Abstract Arginase-2 dependent mechanism underlying the neuroprotective activity of puerarin.

  13. Type I and II positive allosteric modulators differentially modulate agonist-induced up-regulation of α7 nicotinic acetylcholine receptors.

    PubMed

    Thomsen, Morten S; Mikkelsen, Jens D

    2012-10-01

    Long-term treatment with nicotine or selective α7 nicotinic acetylcholine receptor (nAChR) agonists increases the number of α7 nAChRs and this up-regulation may be involved in the mechanism underlying the sustained procognitive effect of these compounds. Here, we investigate the influence of type I and II α7 nAChR positive allosteric modulators (PAMs) on agonist-induced α7 nAChR up-regulation. We show that the type II PAMs, PNU-120596 (10 μM) or TQS (1 and 10 μM), inhibit up-regulation, as measured by protein levels, induced by the α7 nAChR agonist A-582941 (10 nM or 10 μM), in SH-EP1 cells stably expressing human α7 nAChR, whereas the type I PAMs AVL-3288 or NS1738 do not. Contrarily, neither type I nor II PAMs affect 10 μM nicotine-induced receptor up-regulation, suggesting that nicotine and A-582941 induce up-regulation through different mechanisms. We further show in vivo that 3 mg/kg PNU-120596 inhibits up-regulation of the α7 nAChR induced by 10 mg/kg A-582941, as measured by [(125)I]-bungarotoxin autoradiography, whereas 1 mg/kg AVL-3288 does not. Given that type II PAMs decrease desensitization of the receptor, whereas type I PAMs do not, these results suggest that receptor desensitization is involved in A-582941-induced up-regulation. Our results are the first to show an in vivo difference between type I and II α7 nAChR PAMs, and demonstrate an agonist-dependent effect of type II PAMs occurring on a much longer time scale than previously appreciated. Furthermore, our data suggest that nicotine and A-582941 induce up-regulation through different mechanisms, and that this confers differential sensitivity to the effects of α7 nAChR PAMs. These results may have implications for the clinical development of α7 nAChR PAMs.

  14. Myricetin protects against diet-induced obesity and ameliorates oxidative stress in C57BL/6 mice*

    PubMed Central

    Su, Hong-ming; Feng, Li-na; Zheng, Xiao-dong; Chen, Wei

    2016-01-01

    Background: Myricetin is a naturally occurring antioxidant commonly found in various plants. However, little information is available with respect to its direct anti-obesity effects. Objective: This study was undertaken to investigate the effect of myricetin on high-fat diet (HFD)-induced obesity in C57BL/6 mice. Results: Administration of myricetin dramatically reduced the body weight of diet-induced obese mice compared with solely HFD-induced mice. Several parameters related to obesity including serum glucose, triglyceride, and cholesterol were significantly decreased in myricetin-treated mice. Moreover, obesity-associated oxidative stress (glutathione peroxidase (GPX) activity, total antioxidant capacity (T-AOC), and malondialdehyde (MDA)) and inflammation (tumor necrosis factor-α (TNF-α)) were ameliorated in myricetin-treated mice. Further investigation revealed that the protective effect of myricetin against HFD-induced obesity in mice appeared to be partially mediated through the down-regulation of mRNA expression of adipogenic transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), and lipogenic transcription factor sterol regulatory element-binding protein 1c (SREBP-1c). Conclusions: Consumption of myricetin may help to prevent obesity and obesity-related metabolic complications. PMID:27256677

  15. Effect of the cannabinoid receptor-1 antagonist rimonabant on inflammation in mice with diet-induced obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We studied whether cannabinoid receptor (CB1) blockade with rimonabant has an anti-inflammatory effect in obese mice, and whether this effect depends on weight loss and/or diet consumption. High-fat diet (HFD)-induced obese mice were treated orally with rimonabant (HFD-R) or vehicle (HFD-V) for 4 we...

  16. Diet-induced obesity has a differential effect on adipose tissue and macrophage inflammatory responses of young and old mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity and aging are both associated with increased inflammation in adipose tissue. In this study, we investigated the effect of diet-induced obesity on inflammatory status in young and old mice. Young (2-mo) and old (19-mo) C57BL/6 mice were fed a low fat (10 percent LF) or high fat (60 percent, H...

  17. Altered Left Ventricular Ion Channel Transcriptome in a High-Fat-Fed Rat Model of Obesity: Insight into Obesity-Induced Arrhythmogenesis.

    PubMed

    Ashrafi, Reza; Yon, Marianne; Pickavance, Lucy; Yanni Gerges, Joseph; Davis, Gershan; Wilding, John; Jian, Kun; Zhang, Henggui; Hart, George; Boyett, Mark

    2016-01-01

    Introduction. Obesity is increasingly common and is associated with an increased prevalence of cardiac arrhythmias. The aim of this study was to see whether in obesity there is proarrhythmic gene expression of ventricular ion channels and related molecules. Methods and Results. Rats were fed on a high-fat diet and compared to control rats on a normal diet (n = 8). After 8 weeks, rats on the high-fat diet showed significantly greater weight gain and higher adiposity. Left ventricle samples were removed at 8 weeks and mRNA expression of ion channels and other molecules was measured using qPCR. Obese rats had significant upregulation of Cav1.2, HCN4, Kir2.1, RYR2, NCX1, SERCA2a, and RYR2 mRNA and downregulation of ERG mRNA. In the case of HCN4, it was confirmed that there was a significant increase in protein expression. The potential effects of the mRNA changes on the ventricular action potential and intracellular Ca(2+) transient were predicted using computer modelling. Modelling predicted prolongation of the ventricular action potential and an increase in the intracellular Ca(2+) transient, both of which would be expected to be arrhythmogenic. Conclusion. High-fat diet causing obesity results in arrhythmogenic cardiac gene expression of ion channels and related molecules.

  18. Altered Left Ventricular Ion Channel Transcriptome in a High-Fat-Fed Rat Model of Obesity: Insight into Obesity-Induced Arrhythmogenesis

    PubMed Central

    Yon, Marianne; Pickavance, Lucy; Yanni Gerges, Joseph; Davis, Gershan; Wilding, John; Jian, Kun; Hart, George; Boyett, Mark

    2016-01-01

    Introduction. Obesity is increasingly common and is associated with an increased prevalence of cardiac arrhythmias. The aim of this study was to see whether in obesity there is proarrhythmic gene expression of ventricular ion channels and related molecules. Methods and Results. Rats were fed on a high-fat diet and compared to control rats on a normal diet (n = 8). After 8 weeks, rats on the high-fat diet showed significantly greater weight gain and higher adiposity. Left ventricle samples were removed at 8 weeks and mRNA expression of ion channels and other molecules was measured using qPCR. Obese rats had significant upregulation of Cav1.2, HCN4, Kir2.1, RYR2, NCX1, SERCA2a, and RYR2 mRNA and downregulation of ERG mRNA. In the case of HCN4, it was confirmed that there was a significant increase in protein expression. The potential effects of the mRNA changes on the ventricular action potential and intracellular Ca2+ transient were predicted using computer modelling. Modelling predicted prolongation of the ventricular action potential and an increase in the intracellular Ca2+ transient, both of which would be expected to be arrhythmogenic. Conclusion. High-fat diet causing obesity results in arrhythmogenic cardiac gene expression of ion channels and related molecules. PMID:27747100

  19. Activation of AMPK attenuates LPS-induced acute lung injury by upregulation of PGC1α and SOD1

    PubMed Central

    Wang, Guizuo; Song, Yang; Feng, Wei; Liu, Lu; Zhu, Yanting; Xie, Xinming; Pan, Yilin; Ke, Rui; Li, Shaojun; Li, Fangwei; Yang, Lan; Li, Manxiang

    2016-01-01

    Evidence suggests that an imbalance between oxidation and antioxidation is involved in the pathogenesis of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Activation of AMP-activated protein kinase (AMPK) has been shown to inhibit the occurrence of ALI/ARDS. However, it is unknown whether activation of AMPK benefits ALI/ARDS by restoration of the oxidant and antioxidant balance, and which mechanisms are responsible for this process. The present study aimed to address these issues. Lipopolysaccharide (LPS) induced pronounced pathological changes of ALI in mice; these were accompanied by elevated production of malondialdehyde (MDA) and decreased activity of superoxide dismutase (SOD) compared with control mice. Prior treatment of mice with the AMPK agonist metformin significantly suppressed the LPS-induced development of ALI, reduced the elevation of MDA and increased the activity of SOD. Further analysis indicated that activation of AMPK also stimulated the protein expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α) and superoxide dismutase 1 (SOD1). This study suggests that activation of AMPK by metformin inhibits oxidative stress by upregulation of PGC1α and SOD1, thereby suppressing the development of ALI/ARDS, and has potential value in the clinical treatment of such conditions. PMID:27602077

  20. Radiation-Induced Upregulation of Gene Expression From Adenoviral Vectors Mediated by DNA Damage Repair and Regulation

    SciTech Connect

    Nokisalmi, Petri; Rajecki, Maria; Pesonen, Sari; Escutenaire, Sophie; Soliymani, Rabah; Tenhunen, Mikko; Ahtiainen, Laura; Hemminki, Akseli

    2012-05-01

    Purpose: In the present study, we evaluated the combination of replication-deficient adenoviruses and radiotherapy in vitro. The purpose of the present study was to analyze the mechanism of radiation-mediated upregulation of adenoviral transgene expression. Methods and Materials: Adenoviral transgene expression (luciferase or green fluorescent protein) was studied with and without radiation in three cell lines: breast cancer M4A4-LM3, prostate cancer PC-3MM2, and lung cancer LNM35/enhanced green fluorescent protein. The effect of the radiation dose, modification of the viral capsid, and five different transgene promoters were studied. The cellular responses were studied using mass spectrometry and immunofluorescence analysis. Double strand break repair was modulated by inhibitors of heat shock protein 90, topoisomerase-I, and DNA protein kinase, and transgene expression was measured. Results: We found that a wide range of radiation doses increased adenoviral transgene expression regardless of the cell line, transgene, promoter, or viral capsid modification. Treatment with adenovirus, radiation, and double strand break repair inhibitors resulted in persistence of double strand breaks and subsequent increases in adenovirus transgene expression. Conclusions: Radiation-induced enhancement of adenoviral transgene expression is linked to DNA damage recognition and repair. Radiation induces a global cellular response that results in increased production of RNA and proteins, including adenoviral transgene products. This study provides a mechanistic rationale for combining radiation with adenoviral gene delivery.

  1. Azelastine hydrochloride (Azeptin) inhibits peplomycin (PLM)-induced pulmonary fibrosis by contradicting the up-regulation of signal transduction.

    PubMed

    Yoneda, K; Yamamoto, T; Ueta, E; Osaki, T

    1997-10-01

    Inhibition of peplomycin (PLM)-induced pulmonary fibrosis by azelastine hydrochloride (Azeptin) was examined using ICR mice, and the effects of both drugs on signal transduction were investigated. Microscopically, Azeptin (a total of 56 mg/kg for 28 days) suppressed pulmonary fibrosis in mice which received an i.p. injection of a total of 60 or 75 mg/kg PLM. In parallel with the microscopic findings, smaller amounts of collagen were synthesized in the lungs of Azeptin-injected mice. PLM enhanced the expression of interleukin-1 beta- and transforming growth factor-beta-mRNA in lungs. In contrast, Azeptin suppressed the expression. Compatible with these in vivo results, Azeptin and PLM contradictively regulated protein tyrosine phosphorylation and c-myc mRNA expression in human gingival and mouse pulmonary fibroblasts. In addition, NF-kappa B was activated by fibroblast treatment with 5 micrograms/ml PLM for 1 h, but intranuclear NF-kappa B was decreased by cell treatment with 10(-5) M Azeptin. From these results, it is concluded that Azeptin inhibits PLM-induced pulmonary fibrosis by antagonizing the up-regulation of signal transduction.

  2. CCR7 pathway induces epithelial-mesenchymal transition through up-regulation of Snail signaling in gastric cancer.

    PubMed

    Zhang, Jianping; Zhou, Yunzhe; Yang, Yonggang

    2015-02-01

    The chemokine receptor 7 (CCR7) and Snail signaling have been linked to various types of cancers. The associations between these signalings and the epithelial-mesenchymal transition (EMT) are not clear in gastric cancer. Here, the expression of CCR7 and Snail was detected in gastric cancer by immunohistochemistry and Western blot. Meanwhile, gastric cancer cells were subjected to CCL19, si-control, and si-Snail treatment. Cell cycle, migration, and invasion were also analyzed. The expression patterns of CCR7 and Snail were similar in either gastric cancer tissues or cells. The increased expression of CCR7 was closely associated with the increased Snail expression, which both were closely correlated with metastasis, stage and differentiation, and poor prognosis. The increased p-ERK, p-AKT, Snail, and MMP9 expression and the decreased E-cadherin were confirmed in MGC803 cells in a dose-dependent manner in response to CCL19 treatment. However, the blockade of Snail abrogated the up-regulation of MMP9 and down-regulation of E-cadherin. CCR7-induced ERK and PI3K pathway regulated Snail signaling. Besides si-Snail treatment led to MGC803 cell cycle arrest and affected the migration and invasion. In conclusion, our study suggested that CCR7 promotes Snail expression to induce the EMT, resulting in cell cycle progression, migration, and invasion in gastric cancer. CCR7-Snail pathway provided more potential regimens for cancer therapy.

  3. Enhanced cocaine-induced locomotor sensitization and intrinsic excitability of NAc medium spiny neurons in adult but not adolescent rats susceptible to diet-induced obesity

    PubMed Central

    Oginsky, Max F.; Maust, Joel D.; Corthell, John T.; Ferrario, Carrie R.

    2015-01-01

    Rationale Basal and diet-induced differences in mesolimbic function, particularly within the nucleus accumbens (NAc), may contribute to human obesity; these differences may be more pronounced in susceptible populations. Objectives We determined whether there are differences in cocaine-induced behavioral plasticity in rats that are susceptible vs. resistant to diet-induced obesity, and basal differences in the striatal neuron function in adult and adolescent obesity-prone and obesity-resistant rats. Methods Susceptible and resistant outbred rats were identified based on “junk-food” diet-induced obesity. Then, the induction and expression of cocaine-induced locomotor sensitization, which is mediated by enhanced striatal function and is associated with increased motivation for rewards and reward-paired cues, were evaluated. Basal differences in mesolimbic function were examined in selectively bred obesity-prone and obesity-resistant rats (P70-80 and P30-40) using both cocaine induced locomotion and whole-cell patch clamping approaches in NAc core medium spiny neurons (MSNs). Results In rats that became obese after eating “junk-food”, the expression of locomotor sensitization was enhanced compared to non-obese rats, with similarly strong responses to 7.5 and 15 mg/kg cocaine. Without diet manipulation, obesity-prone rats were hyper-responsive to the acute locomotor-activating effects of cocaine, and the intrinsic excitability of NAc core MSNs was enhanced by ~60% at positive and negative potentials. These differences were present in adult, but not adolescent rats. Post-synaptic glutamatergic transmission was similar between groups. Conclusions Mesolimbic systems, particularly NAc MSNs, are hyper-responsive in obesity-prone individuals; and interactions between predisposition and experience influence neurobehavioral plasticity in ways that may promote weight gain and hamper weight loss in susceptible rats. PMID:26612617

  4. Inhalation of Talc Induces Infiltration of Macrophages and Upregulation of Manganese Superoxide Dismutase in Rats.

    PubMed

    Shim, Ilseob; Kim, Hyun-Mi; Yang, Sangyoung; Choi, Min; Seo, Gyun-Baek; Lee, Byung-Woo; Yoon, Byung-Il; Kim, Pilje; Choi, Kyunghee

    2015-01-01

    Talc is a mineral that is widely used in cosmetic products, antiseptics, paints, and rubber manufacturing. Although the toxicological effects of talc have been studied extensively, until now no detailed inhalation study of talc focusing on oxidative stress has been done. This repeated 4 weeks whole-body inhalation toxicity study of talc involved Sprague-Dawley rats. Male and female groups of rats were exposed to inhaled talc at 0, 5, 50, and 100 mg/m(3) for 6 hours daily, 5 days/week for 4 weeks. The objective was to identify the 4-week inhalation toxicity of talc and investigate antioxidant activity after exposure to talc. There were no treatment-related symptoms or mortality in rats treated with talc. Glucose (GLU) was decreased significantly in male rats exposed to 50 and 100 mg/m(3) of talc. Histopathological examination revealed infiltration of macrophages on the alveolar walls and spaces near the terminal and respiratory bronchioles. In male and female rats exposed to 100 mg/m(3) talc, expression of superoxide dismutase 2, a typical biological indicator of oxidative damage, was significantly increased. Thus, inhalation of talc induces macrophage aggregations and oxidative damage in the lung.

  5. Tangeretin induces cell cycle arrest and apoptosis through upregulation of PTEN expression in glioma cells.

    PubMed

    Ma, Li-Li; Wang, Da-Wei; Yu, Xu-Dong; Zhou, Yan-Ling

    2016-07-01

    Tangeretin (TANG), present in peel of citrus fruits, has been shown to various medicinal properties such as chemopreventive and neuroprotective. However, the chemopreventive effect of TANG on glioblastoma cells has not been examined. The present study was designed to explore the anticancer potential of TANG in glioblastoma cells and to investigate the related mechanism. Human glioblastoma U-87MG and LN-18 cells were treated with 45μM concentration of TANG and cell growth was measured by MTT assay. The cell cycle distribution and cell death were measured by flow cytometry. The expression of cell cycle and apoptosis related genes were analyzed by quantitative RT-PCR and western blot. The cells treated with TANG were significantly increased cell growth suppression and cell death effects than vehicle treated cells. Further, TANG treatment increases G2/M arrest and apoptosis by modulating PTEN and cell-cycle regulated genes such as cyclin-D and cdc-2 mRNA and protein expressions. Moreover, the ability of TANG to decrease cell growth and to induce cell death was compromised when PTEN was knockdown by siRNA. Taken together, the chemopreventive effect of TANG is associated with regulation of cell-cycle and apoptosis in glioblastoma, thereby attenuating glioblastoma cell growth. Hence, the present findings suggest that TANG may be a therapeutic agent for glioblastoma treatment.

  6. Upregulation of the alpha1-adrenoceptor-induced phosphoinositide and inotropic response in hypothyroid rat heart.

    PubMed

    Jalali, Shahrzad; Durston, Melanie; Panagia, Vincenzo; Mesaeli, Nasrin

    2006-02-01

    In this study, we examined changes in the biochemical and inotropic events of the alpha(1)-adrenoceptor signaling pathway in hypothyroid rat hearts. Hypothyroidism was induced by treating experimental animals with 0.05% 6-n-propyl-2-thiouracil (PTU) in drinking water for 7 weeks. A significant decrease of beta- and an increase in alpha(1)-adrenoceptor density as well as an increase in the basal activity of the phosphoinositide (4,5) bisphosphate hydrolyzing phospholipase C was observed in sarcolemmal membranes purified from hypothyroid hearts as compared to age-matched euthyroid controls. Following stimulation with 10 microM phenylephrine (in the presence of 10 microM atenolol), the increase of contractile parameters over baseline values was significantly higher in hypo- than euthyroid hearts, while the opposite occurred under beta-stimulation with 0.1 microM isoproterenol. Interestingly, the increase in phenylephrine-mediated positive inotropy was accompanied by a significant increase in the sarcolemmal phospholipase C activity and in the inositol 1,4,5-trisphosphate content in hypothyroid as compared to euthyroid controls. Our results suggest that cardiac alpha(1)-adrenoceptor and its associated phosphoinositide signaling pathway may act as a reserve for catecholamine inotropic response in hypothyroidism, where the beta-adrenoceptors are compromised.

  7. Inflammation-induced microvascular insulin resistance is an early event in diet-induced obesity.

    PubMed

    Zhao, Lina; Fu, Zhuo; Wu, Jing; Aylor, Kevin W; Barrett, Eugene J; Cao, Wenhong; Liu, Zhenqi

    2015-12-01

    Endothelial dysfunction and vascular insulin resistance usually coexist and chronic inflammation engenders both. In the present study, we investigate the temporal relationship between vascular insulin resistance and metabolic insulin resistance. We assessed insulin responses in all arterial segments, including aorta, distal saphenous artery and the microvasculature, as well as the metabolic insulin responses in muscle in rats fed on a high-fat diet (HFD) for various durations ranging from 3 days to 4 weeks with or without sodium salicylate treatment. Compared with controls, HFD feeding significantly blunted insulin-mediated Akt (protein kinase B) and eNOS [endothelial nitric oxide (NO) synthase] phosphorylation in aorta in 1 week, blunted vasodilatory response in small resistance vessel in 4 weeks and microvascular recruitment in as early as 3 days. Insulin-stimulated whole body glucose disposal did not begin to progressively decrease until after 1 week. Salicylate treatment fully inhibited vascular inflammation, prevented microvascular insulin resistance and significantly improved muscle metabolic responses to insulin. We conclude that microvascular insulin resistance is an early event in diet-induced obesity and insulin resistance and inflammation plays an essential role in this process. Our data suggest microvascular insulin resistance contributes to the development of metabolic insulin resistance in muscle and muscle microvasculature is a potential therapeutic target in the prevention and treatment of diabetes and its related complications.

  8. Inhibition of RXR and PPARγ ameliorates diet-induced obesity and type 2 diabetes

    PubMed Central

    Yamauchi, Toshimasa; Waki, Hironori; Kamon, Junji; Murakami, Koji; Motojima, Kiyoto; Komeda, Kajuro; Miki, Hiroshi; Kubota, Naoto; Terauchi, Yasuo; Tsuchida, Atsuko; Tsuboyama-Kasaoka, Nobuyo; Yamauchi, Naoko; Ide, Tomohiro; Hori, Wataru; Kato, Shigeaki; Fukayama, Masashi; Akanuma, Yasuo; Ezaki, Osamu; Itai, Akiko; Nagai, Ryozo; Kimura, Satoshi; Tobe, Kazuyuki; Kagechika, Hiroyuki; Shudo, Koichi; Kadowaki, Takashi

    2001-01-01

    PPARγ is a ligand-activated transcription factor and functions as a heterodimer with a retinoid X receptor (RXR). Supraphysiological activation of PPARγ by thiazolidinediones can reduce insulin resistance and hyperglycemia in type 2 diabetes, but these drugs can also cause weight gain. Quite unexpectedly, a moderate reduction of PPARγ activity observed in heterozygous PPARγ-deficient mice or the Pro12Ala polymorphism in human PPARγ, has been shown to prevent insulin resistance and obesity induced by a high-fat diet. In this study, we investigated whether functional antagonism toward PPARγ/RXR could be used to treat obesity and type 2 diabetes. We show herein that an RXR antagonist and a PPARγ antagonist decrease triglyceride (TG) content in white adipose tissue, skeletal muscle, and liver. These inhibitors potentiated leptin’s effects and increased fatty acid combustion and energy dissipation, thereby ameliorating HF diet-induced obesity and insulin resistance. Paradoxically, treatment of heterozygous PPARγ-deficient mice with an RXR antagonist or a PPARγ antagonist depletes white adipose tissue and markedly decreases leptin levels and energy dissipation, which increases TG content in skeletal muscle and the liver, thereby leading to the re-emergence of insulin resistance. Our data suggested that appropriate functional antagonism of PPARγ/RXR may be a logical approach to protection against obesity and related diseases such as type 2 diabetes. PMID:11581301

  9. Inhibition of RXR and PPARgamma ameliorates diet-induced obesity and type 2 diabetes.

    PubMed

    Yamauchi, T; Waki, H; Kamon, J; Murakami, K; Motojima, K; Komeda, K; Miki, H; Kubota, N; Terauchi, Y; Tsuchida, A; Tsuboyama-Kasaoka, N; Yamauchi, N; Ide, T; Hori, W; Kato, S; Fukayama, M; Akanuma, Y; Ezaki, O; Itai, A; Nagai, R; Kimura, S; Tobe, K; Kagechika, H; Shudo, K; Kadowaki, T

    2001-10-01

    PPARgamma is a ligand-activated transcription factor and functions as a heterodimer with a retinoid X receptor (RXR). Supraphysiological activation of PPARgamma by thiazolidinediones can reduce insulin resistance and hyperglycemia in type 2 diabetes, but these drugs can also cause weight gain. Quite unexpectedly, a moderate reduction of PPARgamma activity observed in heterozygous PPARgamma-deficient mice or the Pro12Ala polymorphism in human PPARgamma, has been shown to prevent insulin resistance and obesity induced by a high-fat diet. In this study, we investigated whether functional antagonism toward PPARgamma/RXR could be used to treat obesity and type 2 diabetes. We show herein that an RXR antagonist and a PPARgamma antagonist decrease triglyceride (TG) content in white adipose tissue, skeletal muscle, and liver. These inhibitors potentiated leptin's effects and increased fatty acid combustion and energy dissipation, thereby ameliorating HF diet-induced obesity and insulin resistance. Paradoxically, treatment of heterozygous PPARgamma-deficient mice with an RXR antagonist or a PPARgamma antagonist depletes white adipose tissue and markedly decreases leptin levels and energy dissipation, which increases TG content in skeletal muscle and the liver, thereby leading to the re-emergence of insulin resistance. Our data suggested that appropriate functional antagonism of PPARgamma/RXR may be a logical approach to protection against obesity and related diseases such as type 2 diabetes.

  10. Persistence of diet-induced obesity despite access to voluntary activity in mice lacking sarcolipin.

    PubMed

    Gamu, Daniel; Trinh, Anton; Bombardier, Eric; Tupling, A Russell

    2015-09-01

    Several rodent models of obesity have been shown to develop excessive adiposity only when voluntary cage ambulation is restricted. We have previously shown that mice lacking the sarco(endo)plasmic reticulum Ca(2+)-ATPase pump regulatory protein sarcolipin (Sln(-/-)), an uncoupler of Ca(2+) uptake, develop excessive diet-induced obesity under standard housing conditions. However, it is unclear whether this phenotype is due, in part, to the sedentary housing environment in which these animals are kept. To address this, we allowed wild-type and Sln(-/-) animals ad libitum access to voluntary wheel running while consuming a standard chow or high-fat diet for 8 weeks. During this period, wheel revolutions were monitored along with weekly mass gain. Postdiet glucose tolerance and visceral adiposity were also taken. The volume of wheel running completed was similar between genotype, regardless of diet. Although voluntary activity reduced mass gain relative to sedentary controls within each diet (P < 0.05), visceral adiposity was surprisingly unaltered with activity. However, Sln(-/-) mice developed excessive obesity (P < 0.05) and glucose intolerance (P < 0.05) with high-fat feeding relative to wild-type controls. These findings indicate that the excessive diet-induced obese phenotype previously observed in Sln(-/-) mice is not the result of severely restricted daily ambulation, but in fact the inability to recruit uncoupling of the Ca(2+)-ATPase pump.

  11. ATP-Induced Inflammation Drives Tissue-Resident Th17 Cells in Metabolically Unhealthy Obesity.

    PubMed

    Pandolfi, Julieta B; Ferraro, Ariel A; Sananez, Inés; Gancedo, Maria C; Baz, Plácida; Billordo, Luis A; Fainboim, Leonardo; Arruvito, Lourdes

    2016-04-15

    Obesity-induced inflammation is conducted by a metabolic pathway, which eventually causes activation of specialized immune cells and leads to an unresolved inflammatory response within the tissue. For this reason, it is critically important to determine how hypertrophic fat tissue alters T cell balance to drive inflammation. In this study, we identify the purinergic signaling as a novel mechanism driving the adaptive Th17 response in human visceral adipose tissue (VAT) of metabolically unhealthy obese patients. We demonstrate that ATP acting via the P2X7 receptor pathway promotes a Th17 polarizing microenvironment with high levels of IL-1β, IL-6, and IL-17 in VAT explants from lean donors. Moreover, in vitro blockade of the P2X7 receptor abrogates the levels of these cytokines. These findings are consistent with a greater frequency of Th17 cells in tissue from metabolically unhealthy obese donors, revealed not only by the presence of a baseline Th17-promoting milieu, but also by the higher expression of steadily recognized Th17 markers, such as RORC, IL-17 cytokine, and IL-23R, in comparison with metabolically healthy obese and lean donors. In addition, we demonstrate that CD39 expression on CD4(+)effector T cells represents a novel Th17 marker in the inflamed VAT, which also confers protection against ATP-induced cell death. The manipulation of the purinergic signaling might represent a new therapeutic target to shift the CD4(+)T cell balance under inflammatory conditions.

  12. Increased inflammatory properties of adipose tissue macrophages recruited during diet-induced obesity.

    PubMed

    Lumeng, Carey N; Deyoung, Stephanie M; Bodzin, Jennifer L; Saltiel, Alan R

    2007-01-01

    Although recent studies show that adipose tissue macrophages (ATMs) participate in the inflammatory changes in obesity and contribute to insulin resistance, the properties of these cells are not well understood. We hypothesized that ATMs recruited to adipose tissue during a high-fat diet have unique inflammatory properties compared with resident tissue ATMs. Using a dye (PKH26) to pulse label ATMs in vivo, we purified macrophages recruited to white adipose tissue during a high-fat diet. Comparison of gene expression in recruited and resident ATMs using real-time RT-PCR and cDNA microarrays showed that recruited ATMs overexpress genes important in macrophage migration and phagocytosis, including interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and C-C chemokine receptor 2 (CCR2). Many of these genes were not induced in ATMs from high-fat diet-fed CCR2 knockout mice, supporting the importance of CCR2 in regulating recruitment of inflammatory ATMs during obesity. Additionally, expression of Apoe was decreased, whereas genes important in lipid metabolism, such as Pparg, Adfp, Srepf1, and Apob48r, were increased in the recruited macrophages. In agreement with this, ATMs from obese mice had increased lipid content compared with those from lean mice. These studies demonstrate that recruited ATMs in obese animals represent a subclass of macrophages with unique properties.

  13. Moderate physical activity promotes basal hepatic autophagy in diet-induced obese mice.

    PubMed

    Rosa-Caldwell, Megan E; Lee, David E; Brown, Jacob L; Brown, Lemuel A; Perry, Richard A; Greene, Elizabeth S; Carvallo Chaigneau, Francisco R; Washington, Tyrone A; Greene, Nicholas P

    2017-02-01

    Obesity is a known risk factor for the development of hepatic disease; obesity-induced fatty liver can lead to inflammation, steatosis, and cirrhosis and is associated with degeneration of the mitochondria. Lifestyle interventions such as physical activity may ameliorate this condition. The purpose of this study was to investigate regulation of mitochondrial and autophagy quality control in liver following Western diet-induced obesity and voluntary physical activity. Eight-week-old C57BL/6J mice were fed a Western diet (WD) or normal chow (NC, control) for 4 weeks; afterwards, groups were divided into voluntary wheel running (VWR) or sedentary (SED) conditions for an additional 4 weeks. WD-SED animals had a median histology score of 2, whereas WD-VWR was not different from NC groups (median score 1). There was no difference in mRNA of inflammatory markers Il6 and Tnfa in WD animals. WD animals had 50% lower mitochondrial content (COX IV and Cytochrome C proteins), 50% lower Pgc1a mRNA content, and reduced content of mitochondrial fusion and fission markers. Markers of autophagy were increased in VWR animals, regardless of obesity, as measured by 50% greater LC3-II/I ratio and 40% lower p62 protein content. BNIP3 protein content was 30% less in WD animals compared with NC animals, regardless of physical activity. Diet-induced obesity results in derangements in mitochondrial quality control that appear to occur prior to the onset of hepatic inflammation. Moderate physical activity appears to enhance basal autophagy in the liver; increased autophagy may provide protection from hepatic fat accumulation.

  14. PI3K-delta mediates double-stranded RNA-induced upregulation of B7-H1 in BEAS-2B airway epithelial cells

    SciTech Connect

    Kan-o, Keiko; Matsumoto, Koichiro; Asai-Tajiri, Yukari; Fukuyama, Satoru; Hamano, Saaka; Seki, Nanae; Nakanishi, Yoichi; Inoue, Hiromasa

    2013-05-31

    Highlights: •Double-stranded RNA upregulates B7-H1 on BEAS-2B airway epithelial cells. •The upregulation of B7-H1 is attenuated by inhibition of PI3Kδ isoform. •PI3Kδ-mediated upregulation of B7-H1 is independent of NF-κB activation. •Inhibition of PI3Kδ may prevent persistent viral infection induced by B7-H1. -- Abstract: Airway viral infection disturbs the health-related quality of life. B7-H1 (also known as PD-L1) is a coinhibitory molecule associated with the escape of viruses from the mucosal immunity, leading to persistent infection. Most respiratory viruses generate double-stranded (ds) RNA during replication. The stimulation of cultured airway epithelial cells with an analog of viral dsRNA, polyinosinic-polycytidylic acid (poly IC) upregulates the expression of B7-H1 via activation of the nuclear factor κB(NF-κB). The mechanism of upregulation was investigated in association with phosphatidylinositol 3-kinases (PI3Ks). Poly IC-induced upregulation of B7-H1 was profoundly suppressed by a pan-PI3K inhibitor and partially by an inhibitor or a small interfering (si)RNA for PI3Kδ in BEAS-2B cells. Similar results were observed in the respiratory syncytial virus-infected cells. The expression of p110δ was detected by Western blot and suppressed by pretreatment with PI3Kδ siRNA. The activation of PI3Kδ is typically induced by oxidative stress. The generation of reactive oxygen species was increased by poly IC. Poly IC-induced upregulation of B7-H1 was attenuated by N-acetyl-L-cysteine, an antioxidant, or by oxypurinol, an inhibitor of xanthine oxidase. Poly IC-induced activation of NF-κB was suppressed by a pan-PI3K inhibitor but not by a PI3Kδ inhibitor. These results suggest that PI3Kδ mediates dsRNA-induced upregulation of B7-H1 without affecting the activation of NF-κB.

  15. Morphological changes in glial fibrillary acidic protein immunopositive astrocytes in the hippocampus of dietary-induced obese mice.

    PubMed

    Cano, Victoria; Valladolid-Acebes, Ismael; Hernández-Nuño, Francisco; Merino, Beatriz; Del Olmo, Nuria; Chowen, Julie A; Ruiz-Gayo, Mariano

    2014-06-06

    Long-term consumption of a high-fat diet (HFD) has been shown to trigger both metabolic and cardiovascular diseases. In contrast, the effect of this type of dietary regime on the central nervous system, particularly outside the hypothalamus, has been investigated poorly. Astrocytes, the most abundant population of glial cells in the brain, are pivotal in regulating glutamatergic transmission as they are responsible for most of the glutamate uptake and metabolism. Mice on an HFD show deficits in learning and memory, together with neurochemical and electrophysiological changes compatible with the impairment in hippocampal glutamatergic activity. Because astrocyte function and morphology have been shown to be interdependent, we speculated whether HFD would trigger changes in astrocyte morphology. For this purpose, we have used a model of diet-induced obesity in mice. We have analyzed astrocyte morphology and density by glial fibrillary acidic protein immunohistochemistry, as well as the expression of the glutamate transporters, GLT-1 (glutamate transporter type-1), and GLAST (astrocyte glutamate transporter), in the CA3 area of the hippocampus. We found that astrocytes from HFD mice showed longer and less abundant projections. These changes were accompanied by the upregulation of both GLT-1 and GLAST. Our data show that the functional impairment detected previously in HFD mice is concomitant with morphological changes within the hippocampus.

  16. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

    PubMed Central

    da Silva, Danielle Cristina Tomaz; Lima-Leopoldo, Ana Paula; Leopoldo, André Soares; de Campos, Dijon Henrique Salomé; do Nascimento, André Ferreira; de Oliveira, Sílvio Assis; Padovani, Carlos Roberto; Cicogna, Antonio Carlos

    2014-01-01

    Background Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Objective Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Methods Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C15 and Ob15) and 30 (C30 and Ob30) consecutive weeks. Obesity was determined by adiposity index. Results The Ob15 group was similar to the C15 group regarding the expression of myocardial collagen type I; however, expression in the Ob30 group was less than C30 group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob30 when compared with Ob15. Obesity did not affect collagen type III expression. Conclusion This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression. PMID:24676371

  17. Diet-Induced Obesity Is Associated with an Impaired NK Cell Function and an Increased Colon Cancer Incidence