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1.
Front Endocrinol (Lausanne) ; 14: 1137308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37025415

RESUMEN

Context: The bone-derived adipokine lipocalin-2 is relevant for body weight regulation by stimulating the leptin-melanocortin pathway. Objective: We aimed to (i) detect variants in the lipocalin-2 gene (LCN2) which are relevant for body weight regulation and/or anorexia nervosa (AN); (ii) describe and characterize the impact of LCN2 and MC4R variants on circulating lipocalin-2 level. Methods: Sanger sequencing of the coding region of LCN2 in 284 children and adolescents with severe obesity or 287 patients with anorexia nervosa. In-silico analyses to evaluate functional implications of detected LCN2 variants. TaqMan assays for rare non-synonymous variants (NSVs) in additional independent study groups. Serum levels of lipocalin-2 were measured by ELISA in 35 females with NSVs in either LCN2 or MC4R, and 33 matched controls without NSVs in the two genes. Results: Fourteen LCN2-variants (five NSVs) were detected. LCN2-p.Leu6Pro and p.Gly9Val located in the highly conserved signal peptide region may induce functional consequences. The secondary structure change of lipocalin-2 due to LCN2-p.Val89Ile may decrease solubility and results in a low lipocalin-2 level in a heterozygotes carrier (female recovered from AN). Lean individuals had lower lipocalin-2 levels compared to patients with obesity (p = 0.033). Conclusion: Lipocalin-2 levels are positively associated with body mass index (BMI). Single LCN2-variants might have a profound effect on lipocalin-2 levels.


Asunto(s)
Anorexia Nerviosa , Lipocalina 2 , Obesidad Mórbida , Adolescente , Niño , Femenino , Humanos , Anorexia Nerviosa/genética , Lipocalina 2/genética , Mutación , Obesidad/metabolismo
2.
Sci Rep ; 12(1): 20617, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36450754

RESUMEN

Tinnitus is a common complaint with potentially negative impact on quality of life. Prevalence of tinnitus ranges from 5 to 43% worldwide. This variation could be due to the heterogeneity of tinnitus assessment. This has limited the progress in understanding tinnitus. Therefore, we employed a standardized and a validated assessment method to determine the prevalence and related risk factors of tinnitus among Palestinians for the first time. This is a cross-sectional study in which we questioned a representative sample of 618 subjects in one-to-one interviews. The prevalence of any tinnitus was 30.6% among adult Palestinians. Participants from the oldest age group were almost five times more likely to have tinnitus. Moreover, participants with head and neck pain syndrome, severe hearing impairment, sleeping disorders or frequent complaints of vertigo were approximately two times more likely to have tinnitus. Our study provides novel information regarding tinnitus in Palestine and improves our understanding of tinnitus. This will improve the diagnosis and consequently will contribute in reducing the prevalence and perhaps in preventing tinnitus. As tinnitus still has no known cure, further investigations of modifiable risk factors and causes of tinnitus are crucial to prevent it in the future.


Asunto(s)
Acúfeno , Adulto , Humanos , Estudios Transversales , Prevalencia , Acúfeno/epidemiología , Acúfeno/etiología , Árabes , Calidad de Vida , Factores de Riesgo
3.
Transl Psychiatry ; 12(1): 241, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35680849

RESUMEN

Genetic factors are relevant for both eating disorders and body weight regulation. A recent genome-wide association study (GWAS) for anorexia nervosa (AN) detected eight genome-wide significant chromosomal loci. One of these loci, rs10747478, was also genome-wide and significantly associated with body mass index (BMI). The nearest coding gene is the Polypyrimidine Tract Binding Protein 2 gene (PTBP2). To detect mutations in PTBP2, Sanger sequencing of the coding region was performed in 192 female patients with AN (acute or recovered) and 191 children or adolescents with (extreme) obesity. Twenty-five variants were identified. Twenty-three of these were predicted to be pathogenic or functionally relevant in at least one in silico tool. Two novel synonymous variants (p.Ala77Ala and p.Asp195Asp), one intronic SNP (rs188987764), and the intronic deletion (rs561340981) located in the highly conserved region of PTBP2 may have functional consequences. Ten of 20 genes interacting with PTBP2 were studied for their impact on body weight regulation based on either previous functional studies or GWAS hits for body weight or BMI. In a GWAS for BMI (Pulit et al. 2018), the number of genome-wide significant associations at the PTBP2 locus was different between males (60 variants) and females (two variants, one of these also significant in males). More than 65% of these 61 variants showed differences in the effect size pertaining to BMI between sexes (absolute value of Z-score >2, two-sided p < 0.05). One LD block overlapping 5'UTR and all coding regions of PTBP2 comprises 56 significant variants in males. The analysis based on sex-stratified BMI GWAS summary statistics implies that PTBP2 may have a more pronounced effect on body weight regulation in males than in females.


Asunto(s)
Anorexia Nerviosa , Estudio de Asociación del Genoma Completo , Adolescente , Anorexia Nerviosa/genética , Índice de Masa Corporal , Peso Corporal/genética , Niño , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Proteínas del Tejido Nervioso/genética , Polimorfismo de Nucleótido Simple , Proteína de Unión al Tracto de Polipirimidina/genética
4.
Biomed Res Int ; 2020: 6965306, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33415153

RESUMEN

Pellitory plant (Parietaria judaica (PJ)) is one of the most widely used Arabian traditional medicinal plants due to its ability to cure several infectious diseases and other illnesses. The current study is aimed at assessing the phytoconstituents, antilipase, antiamylase, antimicrobial, and cytotoxic characters of the Pellitory plant (Parietaria judaica (PJ)). Phytochemical screening and procyanidin detection were conducted according to the standard phytochemical procedures. Porcine pancreatic lipase and α-amylase inhibitory activities were carried out using p-nitrophenyl butyrate and dinitrosalicylic acid assays, respectively. In addition, antimicrobial activity was determined utilizing a microdilution assay against several bacterial and fungal strains. Besides, the cytotoxic effect against HeLa cell line was tested employing 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. The quantitative test results revealed that the methanol fraction of PJ contains 18.55 ± 0.55 mg of procyanidin and has a potential α-amylase inhibitory activity compared with the antidiabetic drug Acarbose with IC50 values of 15.84 ± 2.25 and 28.18 ± 1.22 µg/ml, respectively. Also, it has a potential antilipase activity compared to the commercial antiobesity drug, Orlistat, with IC50 values of 38.9 ± 0.29 and 12.3 ± 0.35 µg/ml, respectively. The acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity against the screened bacterial strains, while the acetone fraction has shown anticandidal activity with a MIC value of 0.195 mg/ml. The PJ hexane and acetone fractions decreased HeLa cell viability significantly (p value < 0.0001) by approximately 90% at the concentration of 0.625 mg/ml. The revealed outcomes showed that the methanol fraction has strong α-amylase and lipase inhibitory characters. Besides, acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity, while the acetone fraction revealed potent antifungal activity against Candida albicans. Moreover, at low concentrations, hexane and acetone fractions have potent cytotoxic and antiproliferative activity against HeLa cancer cells. Nevertheless, PJ acetone, hexane, and methanol fractions can serve as an effective source of natural products to develop new antiobesity, antidiabetic, antimicrobial, and anticancer agents.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Parietaria/química , Fitoquímicos/farmacología , Animales , Biflavonoides/análisis , Calibración , Catequina/análisis , Muerte Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Células HeLa , Humanos , Lipasa/antagonistas & inhibidores , Lipasa/metabolismo , Pruebas de Sensibilidad Microbiana , Proantocianidinas/análisis , Porcinos , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo
5.
BMC Pediatr ; 19(1): 483, 2019 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-31818270

RESUMEN

BACKGROUND: Childhood obesity is rising in developed and developing countries, while childhood underweight is rising mainly in developing countries. Childhood underweight has been shown to increase a child's risk of rapid weight gain. Overweight and obese children are more likely to become obese adults, which increases the risk of type-II diabetes and cardiovascular diseases. Studies concerning obesity among Palestinian children are scarce. The prevalence of obesity among Palestinian children has increased from 3 to 6% within 5 years in comparison to the worldwide rise from 1 to 7%, within 41 years. We aim to determine the current prevalence of underweight, overweight and obesity among Palestinian school-age children and to assess the role of dietary and sociodemographic factors. METHODOLOGY: A cross sectional study was conducted in Palestine in 2017. A total of 1320 school-age children and their 2640 corresponding parents were recruited. A written questionnaire was filled out by the parents. Anthropometric indices were measured and categorized according to the Center for Disease Control and prevention (CDC). RESULTS: The mean ± SD age of the children was 9.5 ± 1.5 years and 48.8% were females. The prevalence of underweight, overweight and obesity among the children was approximately 7.3% (95% CI = 5.9-8.8%), 14.5% (95% CI = 12.7-16.6%) and 15.7% (95% CI = 13.8-17.8%) respectively. Multinomial logistic regression analysis demonstrated a significant correlation of waist circumference, age, gender and living place with the body mass indexes of the students. CONCLUSION: Our findings highlighted the accelerated increase in the prevalence of underweight, overweight and obesity (37.5%) among Palestinian children within a very short time in comparison to the globe. Therefore, Interventions aiming to prevent obesity and underweight at an early stage might be vital to avoid obesity later in life and its health-related co-morbidities, e.g. type-II diabetes and cardiovascular diseases.


Asunto(s)
Obesidad Infantil/epidemiología , Delgadez/epidemiología , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Medio Oriente/epidemiología , Prevalencia , Factores de Riesgo
6.
Daru ; 27(2): 645-652, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31512194

RESUMEN

Adipose tissue is a primary site of obesity-induced inflammation, which has been emerging as an important contributor to obesity associated disorders. The factors influencing adipose tissue-induced inflammation and the resulting pathophysiological events remain poorly understood. However, dietary fiber consumptions appear to be protective. Short-chain fatty acids such as propionic acid (PA) are the principal products of the dietary fiber fermentation by microbiota. Therefore, we aim to investigate the influence of PA on inflammation, lipogenesis and glucose uptake markers from human subcutaneous adipose tissue (SAT). We showed that the treatment of SAT with PA resulted in a significant downregulation of inflammatory parameters (e.g. TNF-α and IP-10) and macrophage markers (e.g. CD163 and MMP-9). The expression levels of PA receptors (i.e. G protein coupled receptor-41 and -43) in human primary adipocytes were very low in comparison with SAT and macrophages. Upon PA treatment, no anti-inflammatory effect was observed in human adipocytes. PA significantly upregulated the expression of lipoprotein lipase (LPL), sterol regulatory-element-binding protein-1c (SREBP-1c) and glucose transporter 4 (GLUT-4), which are associated with lipogenesis and glucose uptake. We also showed that the observed anti-inflammatory effects of PA on SAT were partly mediated by Gi/o protein coupled receptor. Our data suggests that PA anti-inflammatory effects on SAT are mediated partly via Gi/o proteins, leading to the improved expression of factors associated with lipogenesis and glucose uptake. These responses appeared to be not mediated by adipocytes; but most probably by macrophages. The current study provides new knowledge, which can be used as a potential new avenue for drug development in preventing obesity-related inflammation and metabolic disorders in future. Graphical abstract Schematic presentation of study flow and the components of the investigation. In this study the effect of propionic acid (PA) on inflammation investigated in human subcutaneous adipose tissue (SAT), human primary adipocytes and the expression of a few hallmark inflammatory components produced by SAT and human adipocytes.


Asunto(s)
Antiinflamatorios/farmacología , Citocinas/genética , Propionatos/farmacología , Grasa Subcutánea/efectos de los fármacos , Antígenos CD/genética , Antígenos de Diferenciación Mielomonocítica/genética , Quimiocina CXCL10/genética , Regulación hacia Abajo , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Metaloproteinasa 9 de la Matriz/genética , Persona de Mediana Edad , Receptores de Superficie Celular/genética , Grasa Subcutánea/inmunología , Factor de Necrosis Tumoral alfa/genética
7.
Biomed Res Int ; 2018: 4034689, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30151381

RESUMEN

INTRODUCTION: In traditional medicine, many pharmacological activities have already been ascribed to the genus of Teucrium plant. These include antirheumatic antispasmodic, anthelmintic, diuretic, hypoglycemic, and anticancer effects. The recent investigation aimed to characterize and estimate the chemical composition, anti-inflammatory, antioxidant, and anticancer potentials of the essential oil isolated by the microwave-ultrasonic apparatus from Teucrium pruinosum leaves collected from Palestine. METHODS: The essential oil (EO) was analyzed by Gas Chromatography equipped with mass spectrometry (GC-MS), while its anticancer activity was evaluated against HeLa cervical adenocarcinoma cells. The ability of T. pruinosum EO to inhibit the conversion of Arachidonic Acid (AA) to PGH2 by ovine COX-1 and human recombinant COX-2 was determined using a COX inhibitor screening assay. In addition, the antioxidant activity of the EO was evaluated on the basis of the scavenging activity with a stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, while Trolox was used as a positive control. RESULTS: Forty-four molecules were identified in T. pruinosum EO, representing 100% of the total EO. Agarospirol was found to be the most abundant component (45.53%) followed by caryophyllene (19.35%). However, the cyclooxygenase inhibitor assay revealed that T. pruinosum has potential COX-1 and Cox-2 inhibitory activity with IC50 values of 0.25 µg/ml and 0.5 µg/ml, respectively. Moreover, the T. pruinosum EO showed moderate antioxidant capacity with an IC50 value of 16.98±0.84 µg/ml in comparison with the positive control Trolox, which has an antioxidant potential with an IC50 value of 2.09±0.17 µg/ml. In addition, 250, 125, 62.5, 31.25, 15.625, 7.67, and 3.84 mg/ml of T. pruinosum EO treatments inhibited mitochondrial activity (cell viability) significantly and extremely by 90-95%. CONCLUSION: The current study provided data that revealed that the T. pruinosum EO could be a suitable candidate for use as a novel anticancer, anti-inflammatory, and antioxidant medication. Further clinical trials would be required to ensure these effects and to allow the design of suitable pharmaceutical dosage forms from this natural oil.


Asunto(s)
Antioxidantes/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Aceites Volátiles/química , Teucrium/química , Animales , Antiinflamatorios , Cromatografía de Gases y Espectrometría de Masas , Humanos , Aceites Volátiles/farmacología , Ovinos
9.
Sci Rep ; 5: 8816, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25743104

RESUMEN

Lipid droplets (LDs) hypertrophy in adipocytes is the main cause of energy metabolic system dysfunction, obesity and its afflictions such as T2D. However, the role of adipocytes in linking energy metabolic disorders with insulin regulation is unknown in humans. Human adipocytes constitutively synthesize and secrete insulin, which is biologically functional. Insulin concentrations and release are fat mass- and LDs-dependent respectively. Fat reduction mediated by bariatric surgery repairs obesity-associated T2D. The expression of genes, like PCSK1 (proinsulin conversion enzyme), GCG (Glucagon), GPLD1, CD38 and NNAT, involved in insulin regulation/release were differentially expressed in pancreas and adipose tissue (AT). INS (insulin) and GCG expression reduced in human AT-T2D as compared to AT-control, but remained unchanged in pancreas in either state. Insulin levels (mRNA/protein) were higher in AT derived from prediabetes BB rats with destructed pancreatic ß-cells and controls than pancreas derived from the same rats respectively. Insulin expression in 10 human primary cell types including adipocytes and macrophages is an evidence for extrapancreatic insulin-producing cells. The data suggest a crosstalk between AT and pancreas to fine-tune energy metabolic system or may minimize the metabolic damage during diabetes. This study opens new avenues towards T2D therapy with a great impact on public health.


Asunto(s)
Adipocitos/metabolismo , Insulina/metabolismo , Gotas Lipídicas/metabolismo , Adipocitos/citología , Adipocitos/patología , Animales , Biomarcadores , Diferenciación Celular/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Perfilación de la Expresión Génica , Humanos , Insulina/genética , Gotas Lipídicas/patología , Transporte de Proteínas , ARN Mensajero/genética , Ratas
10.
Mol Cell Biol ; 33(7): 1303-16, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23339868

RESUMEN

Angiopoietin-like protein 4 (ANGPTL4/FIAF) has been proposed as a circulating mediator between the gut microbiota and fat storage. Here, we show that transcription and secretion of ANGPTL4 in human T84 and HT29 colon adenocarcinoma cells is highly induced by physiological concentrations of short-chain fatty acids (SCFA). SCFA induce ANGPTL4 by activating the nuclear receptor peroxisome proliferator activated receptor γ (PPARγ), as demonstrated using PPARγ antagonist, PPARγ knockdown, and transactivation assays, which show activation of PPARγ but not PPARα and PPARδ by SCFA. At concentrations required for PPARγ activation and ANGPTL4 induction in colon adenocarcinoma cells, SCFA do not stimulate PPARγ in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPARγ modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modeling. Consistent with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPARγ. Our data point to activation of PPARs as a novel mechanism of gene regulation by SCFA in the colon, in addition to other mechanisms of action of SCFA.


Asunto(s)
Adenocarcinoma/metabolismo , Angiopoyetinas/biosíntesis , Neoplasias del Colon/metabolismo , Ácidos Grasos Volátiles/metabolismo , PPAR gamma/metabolismo , Células 3T3-L1 , Adenocarcinoma/genética , Adipogénesis/genética , Proteína 4 Similar a la Angiopoyetina , Angiopoyetinas/genética , Angiopoyetinas/metabolismo , Animales , Línea Celular Tumoral , Colon/metabolismo , Neoplasias del Colon/genética , Células HT29 , Humanos , Inulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , PPAR gamma/agonistas , PPAR gamma/genética , Transcripción Genética , Activación Transcripcional
11.
Gastroenterol Res Pract ; 2012: 895462, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22315590

RESUMEN

Colon cancer is a serious health problem, and novel preventive and therapeutical avenues are urgently called for. Delivery of proteins with anticancer activity through genetically modified bacteria provides an interesting, potentially specific, economic and effective approach here. Interestingly, bone morphogenetic protein 2 (BMP-2) is an important and powerful tumour suppressor in the colon and is thus an attractive candidate protein for delivery through genetically modified bacteria. It has not been shown, however, that BMP production in the bacterial context is effective on colon cancer cells. Here we demonstrate that transforming E. coli with a cDNA encoding an ileal-derived mature human BMP-2 induces effective apoptosis in an in vitro model system for colorectal cancer, whereas the maternal organism was not effective in this respect. Furthermore, these effects were sensitive to cotreatment with the BMP inhibitor Noggin. We propose that prevention and treatment of colorectal cancer using transgenic bacteria is feasible.

12.
Eur J Clin Invest ; 42(4): 357-64, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21913915

RESUMEN

BACKGROUND: Adipose tissue is a primary site of obesity-induced inflammation, which is emerging as an important contributor to obesity-related diseases such as type 2 diabetes. Dietary fibre consumption appears to be protective. Short-chain fatty acids, e.g. propionic acid, are the principal products of the colonic fermentation of dietary fibre and may have beneficial effects on adipose tissue inflammation. MATERIALS AND METHODS: Human omental adipose tissue explants were obtained from overweight (mean BMI 28·8) gynaecological patients who underwent surgery. Explants were incubated for 24 h with propionic acid. Human THP-1 monocytic cells were differentiated to macrophages and incubated with LPS in the presence and absence of propionic acid. Cytokine and chemokine production were determined by multiplex-ELISA, and mRNA expression of metabolic and macrophages genes was determined by RT-PCR. RESULTS: Treatment of adipose tissue explants with propionic acid results in a significant down-regulation of several inflammatory cytokines and chemokines such as TNF-α and CCL5. In addition, expression of lipoprotein lipase and GLUT4, associated with lipogenesis and glucose uptake, respectively, increased. Similar effects on cytokine and chemokine production by macrophages were observed. CONCLUSION: We show that propionic acid, normally produced in the colon, may have a direct beneficial effect on visceral adipose tissue, reducing obesity-associated inflammation and increasing lipogenesis and glucose uptake. Effects on adipose tissue as a whole are at least partially explained by effects on macrophages but likely also adipocytes are involved. This suggests that, in vivo, propionic acid and dietary fibres may have potential in preventing obesity-related inflammation and associated diseases.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Diabetes Mellitus Tipo 2/metabolismo , Sobrepeso/inmunología , Propionatos/farmacología , Tejido Adiposo/inmunología , Tejido Adiposo/metabolismo , Células Cultivadas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Ensayo de Inmunoadsorción Enzimática , Femenino , Transportador de Glucosa de Tipo 4/metabolismo , Humanos , Lipoproteína Lipasa/metabolismo , Macrófagos/inmunología , Epiplón/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
PLoS One ; 6(3): e17154, 2011 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-21448265

RESUMEN

BACKGROUND: Obesity promotes inflammation in adipose tissue (AT) and this is implicated in pathophysiological complications such as insulin resistance, type 2 diabetes and cardiovascular disease. Although based on the classical hypothesis, necrotic AT adipocytes (ATA) in obese state activate AT macrophages (ATM) that then lead to a sustained chronic inflammation in AT, the link between human adipocytes and the source of inflammation in AT has not been in-depth and systematically studied. So we decided as a new hypothesis to investigate human primary adipocytes alone to see whether they are able to prime inflammation in AT. METHODS AND RESULTS: Using mRNA expression, human preadipocytes and adipocytes express the cytokines/chemokines and their receptors, MHC II molecule genes and 14 acute phase reactants including C-reactive protein. Using multiplex ELISA revealed the expression of 50 cytokine/chemokine proteins by human adipocytes. Upon lipopolysaccharide stimulation, most of these adipocyte-associated cytokines/chemokines and immune cell modulating receptors were up-regulated and a few down-regulated such as (ICAM-1, VCAM-1, MCP-1, IP-10, IL-6, IL-8, TNF-α and TNF-ß highly up-regulated and IL-2, IL-7, IL-10, IL-13 and VEGF down-regulated. In migration assay, human adipocyte-derived chemokines attracted significantly more CD4+ T cells than controls and the number of migrated CD4+ cells was doubled after treating the adipocytes with LPS. Neutralizing MCP-1 effect produced by adipocytes reduced CD4+ migration by approximately 30%. CONCLUSION: Human adipocytes express many cytokines/chemokines that are biologically functional. They are able to induce inflammation and activate CD4+ cells independent of macrophages. This suggests that the primary event in the sequence leading to chronic inflammation in AT is metabolic dysfunction in adipocytes, followed by production of immunological mediators by these adipocytes, which is then exacerbated by activated ATM, activation and recruitment of immune cells. This study provides novel knowledge about the prime of inflammation in human obese adipose tissue, opening a new avenue of investigations towards obesity-associated type 2 diabetes.


Asunto(s)
Adipocitos/citología , Adipocitos/inmunología , Inflamación/patología , Macrófagos/citología , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Adipocitos/ultraestructura , Biomarcadores/metabolismo , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular/genética , Movimiento Celular , Células Cultivadas , Quimiocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Regulación de la Expresión Génica , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Activación de Linfocitos/inmunología , Macrófagos/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteómica , Receptores de Quimiocina/metabolismo
14.
Biochim Biophys Acta ; 1801(11): 1175-83, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20691280

RESUMEN

Undigested food is fermented in the colon by the microbiota and gives rise to various microbial metabolites. Short-chain fatty acids (SCFA), including acetic, propionic and butyric acid, are the principal metabolites produced. However, most of the literature focuses on butyrate and to a lesser extent on acetate; consequently, potential effects of propionic acid (PA) on physiology and pathology have long been underestimated. It has been demonstrated that PA lowers fatty acids content in liver and plasma, reduces food intake, exerts immunosuppressive actions and probably improves tissue insulin sensitivity. Thus increased production of PA by the microbiota might be considered beneficial in the context of prevention of obesity and diabetes type 2. The molecular mechanisms by which PA may exert this plethora of physiological effects are slowly being elucidated and include intestinal cyclooxygenase enzyme, the G-protein coupled receptors 41 and 43 and activation of the peroxisome proliferator-activated receptor γ, in turn inhibiting the sentinel transcription factor NF-κB and thus increasing the threshold for inflammatory responses in general. Taken together, PA emerges as a major mediator in the link between nutrition, gut microbiota and physiology.


Asunto(s)
Propionatos/farmacología , Tejido Adiposo/metabolismo , Animales , Niño , Trastornos Generalizados del Desarrollo Infantil/patología , Colon/microbiología , Diabetes Mellitus Tipo 2/prevención & control , Digestión/fisiología , Ácidos Grasos/química , Humanos , Insulina/metabolismo , Ratones , FN-kappa B/metabolismo , Obesidad/prevención & control , PPAR gamma/metabolismo , Propionatos/metabolismo , Ratas , Receptores Acoplados a Proteínas G/metabolismo
15.
Eur J Clin Invest ; 40(5): 401-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20353437

RESUMEN

BACKGROUND: Dietary fibre (DF) has been shown to be protective for the development of obesity, insulin resistance and type 2 diabetes. Short-chain fatty acids, produced by colonic fermentation of DF might mediate this beneficial effect. Adipose tissue plays a key role in the regulation of energy homeostasis, therefore, we investigated the influence of the short-chain fatty acid propionic acid (PA) on leptin, adiponectin and resistin production by human omental (OAT) and subcutaneous adipose tissue (SAT). As PA has been shown to be a ligand for G-protein coupled receptor (GPCR) 41 and 43, we investigated the role of GPCR's in PA signalling. MATERIALS AND METHODS: Human OAT and SAT explants were obtained from gynaecological patients who underwent surgery. Explants were incubated for 24 h with PA. Adipokine secretion and mRNA expression were determined using ELISA and RT-PCR respectively. RESULTS: We found that PA significantly stimulated leptin mRNA expression and secretion by OAT and SAT, whereas it had no effect on adiponectin. Furthermore, PA reduced resistin mRNA expression. Leptin induction, but not resistin reduction, was abolished by inhibition of Gi/o-coupled GPCR signalling. Moreover, GPCR41 and GPCR43 mRNA levels were considerably higher in SAT than in OAT. CONCLUSIONS: We demonstrate that PA stimulates expression of the anorexigenic hormone leptin and reduces the pro-inflammatory factor resistin in human adipose tissue depots. This suggests that PA is involved in regulation of human energy metabolism and inflammation and in this way may influence the development of obesity and type 2 diabetes.


Asunto(s)
Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Propionatos/uso terapéutico , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Expresión Génica , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
16.
Mol Nutr Food Res ; 52(8): 913-20, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18504703

RESUMEN

The gastrointestinal tract is a complex niche and the main port of entry of many pathogens that trigger a wide range of diseases like inflammatory bowel disease (IBD) and colon cancer. Antibodies are effective for treating such diseases, but a system capable of local delivery at the site of the pathology, thus avoiding systemic side effects, is not yet available. Here we report a novel recombinant scFvSIgA1 protein produced by Lactococcus lactis, anchored to the bacterial membrane, which retains its full immuno-recognizing potential. This scFv fragment employed was specific for a colon cancer epitope, epithelial glycoprotein protein-2 (EGP-2). Accordingly L. lactis expressing this chimeric protein was capable of binding cells expressing this epitope. Expression of specific antibodies on bacteria may allow local delivery of anticancer agents produced by such bacteria in conjunction with the antibody and provides a new avenue in the quest for targeted drug delivery.


Asunto(s)
Neoplasias del Colon/terapia , Terapia Genética , Inmunoglobulina A Secretora/genética , Fragmentos de Inmunoglobulinas/genética , Lactococcus lactis/genética , Animales , Células COS , Chlorocebus aethiops , Vectores Genéticos , Humanos , Células Jurkat , Transfección
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