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1.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928475

RESUMO

Increased fructose consumption and chronic stress, the major characteristics of modern lifestyle, impact human health; however, the consequences of their combination on the uterus remain understudied. In this study, we investigated contractile activity, morphology, and intracellular activity of antioxidant enzymes in uteri from virgin Wistar rats subjected to liquid fructose supplementation and/or unpredictable stress over 9 weeks. Contractile activity and uterine response to oxytocin or adrenaline were examined ex vivo using isolated bath chambers. Fructose supplementation, irrespective of stress, affected uterine morphology by increasing endometrium while decreasing myometrium volume density, attenuated uterine response to increasing doses of oxytocin, and increased glutathione peroxidase activity. Stress, irrespective of fructose, attenuated dose-dependent adrenaline-induced uterine relaxation. Stress, when applied solely, decreased mitochondrial superoxide dismutase activity. In the combined treatment, irregular estrous cycles and both reduced response to oxytocin and to adrenaline (as a consequence of fructose consumption and exposure to stress), along with fructose-related alteration of uterine morphology, were detected. In conclusion, fructose and stress affect uterine contractile activity, irrespective of each other, by inducing completely distinct responses in isolated uteri. In the combined treatment, the effects of both factors were evident, suggesting that the combination exerts more detrimental effects on the uterus than each factor individually.


Assuntos
Frutose , Ocitocina , Ratos Wistar , Contração Uterina , Útero , Animais , Feminino , Frutose/efeitos adversos , Frutose/farmacologia , Ratos , Contração Uterina/efeitos dos fármacos , Ocitocina/farmacologia , Ocitocina/metabolismo , Útero/efeitos dos fármacos , Útero/metabolismo , Epinefrina/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Psicológico , Superóxido Dismutase/metabolismo , Suplementos Nutricionais , Miométrio/efeitos dos fármacos , Miométrio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo
2.
Horm Behav ; 153: 105392, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37295324

RESUMO

Polycystic ovary syndrome (PCOS) is a complex disorder characterized by endocrine and metabolic abnormalities such as obesity and insulin resistance. PCOS is also associated with psychiatric disorders and cognitive impairment. The animal model of PCOS was induced by treating rats with 5α-dihydrotestosterone (5α-DHT) and additionally modified to induce adiposity by litter size reduction (LSR). Spatial learning and memory were assessed using the Barnes Maze test, and striatal markers of synaptic plasticity were analyzed. Striatal insulin signaling was estimated by the levels of insulin receptor substrate 1 (IRS1), its inhibitory phosphorylation at Ser307, and glycogen synthase kinase-3α/ß (GSK3α/ß) activity. Both LSR and DHT treatment significantly decreased striatal protein levels of IRS1, followed by increased GSK3α/ß activity in small litters. Results of the behavioral study showed that LSR had a negative effect on learning rate and memory retention, whereas DHT treatment did not induce impairment in memory formation. While protein levels of synaptophysin, GAP43, and postsynaptic density protein 95 (PSD-95) were not altered by the treatments, DHT treatment induced an increase in phosphorylation of PSD-95 at Ser295 in both normal and small litters. This study revealed that LSR and DHT treatment suppressed insulin signaling by downregulating IRS1 in the striatum. However, DHT treatment did not have an adverse effect on learning and memory, probably due to compensatory elevation in pPSD-95-Ser295, which had a positive effect on synaptic strength. This implies that hyperandrogenemia in this setting does not represent a threat to spatial learning and memory, opposite to the effect of overnutrition-related adiposity.


Assuntos
Hiperandrogenismo , Resistência à Insulina , Síndrome do Ovário Policístico , Feminino , Humanos , Ratos , Animais , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Hiperandrogenismo/complicações , Hiperandrogenismo/metabolismo , Aprendizagem Espacial , Resistência à Insulina/fisiologia , Insulina/metabolismo , Di-Hidrotestosterona/farmacologia , Obesidade/complicações , Modelos Animais de Doenças
3.
Int J Mol Sci ; 23(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36012206

RESUMO

Polycystic ovary syndrome (PCOS) is a well-known reproductive syndrome usually associated with obesity, insulin resistance, and hyperinsulinemia. Although the first signs of PCOS begin early in adolescence, it is underexplored whether peripubertal obesity predisposes women to PCOS metabolic disturbances. To highlight that, we examined the impact of postnatal overfeeding-induced obesity, achieved by litter size reduction during the suckling period, on metabolic disturbances associated with visceral and subcutaneous adipose tissue (VAT and SAT) function in the 5α-dihydrotestosterone (5α-DHT)-induced animal model of PCOS. We analyzed markers of insulin signaling, lipid metabolism, and energy sensing in the VAT and SAT. Our results showed that postnatally overfed DHT-treated Wistar rats had increased VAT mass with hypertrophic adipocytes, together with hyperinsulinemia and increased HOMA index. In the VAT of these animals, insulin signaling remained unchanged while lipogenic markers decreased, which was accompanied by increased AMPK activation. In the SAT of the same animals, markers of lipogenesis and lipolysis increased, while the activity of AMPK decreased. Taken together, obtained results showed that postnatal overfeeding predisposes development of PCOS systemic insulin resistance, most likely as a result of worsened metabolic function of SAT, while VAT preserved its tissue insulin sensitivity through increased activity of AMPK.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/metabolismo , Animais , Feminino , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Obesidade/metabolismo , Síndrome do Ovário Policístico/metabolismo , Ratos , Ratos Wistar , Gordura Subcutânea/metabolismo
4.
Int J Mol Sci ; 23(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36012287

RESUMO

The effects of a fructose-rich diet and chronic stress on copper metabolism in the kidneys are still understudied. We investigated whether fructose and/or chronic unpredictable stress modulate copper metabolism in a way that affects redox homeostasis, thus contributing to progression of metabolic disturbances in the kidney. We determined protein level of copper transporters, chaperones, and cuproenzymes including cytochrome c oxidase, as well as antioxidant enzymes function in the kidneys of male Wistar rats subjected to 20% liquid fructose supplementation and/or chronic stress. Liquid fructose supplementation increased level of copper chaperone of superoxide dismutase and decreased metallothionein level, while rendering the level of copper importer and copper chaperones involved in copper delivery to mitochondria and trans Golgi network unaffected. Stress had no effect on renal copper metabolism. The activity and expression of renal antioxidant enzymes remained unaltered in all experimental groups. In conclusion, fructose, independently of stress, decreased renal copper level, and modulated renal copper metabolism as to preserve vital cellular function including mitochondrial energy production and antioxidative defense, at the expense of intracellular copper storage.


Assuntos
Antioxidantes , Frutose , Animais , Antioxidantes/farmacologia , Cobre/farmacologia , Frutose/metabolismo , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar
5.
J Nutr ; 151(12): 3661-3670, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34510217

RESUMO

BACKGROUND: Both fructose consumption and chronic stress contribute to the development of metabolic disorders. The consequences of such combination are not fully understood. OBJECTIVE: We investigated whether fructose supplementation and chronic stress synergistically disturb hepatic lipid and glucose metabolism. The role of energy sensing, redox, and inflammatory status during development of metabolic disturbances was investigated. METHODS: Female Wistar rats, aged 2.5 mo, were divided into 4 experimental groups: control (C) fed a standard diet (commercial food and drinking water); fructose (F) fed the same food and 10% fructose solution; stress (S) fed the standard diet and subjected to chronic unpredictable stress and, stress + fructose (SF) combining conditions F and S as above. Stress included daily stressors: cold water forced swimming, physical restraint, cold room, wet bedding, rocking, switching, or tilting cages. After 9 wk, hepatic enzymes and transcription factors involved in gluconeogenesis, lipogenesis, fatty acid oxidation, antioxidative defence, energy sensing, and cytokines were assessed by qPCR, Western blotting, and spectrophotometry and analyzed by 2-factor ANOVA. RESULTS: Fructose increased AMP-activated protein kinase (AMPK) phosphorylation (40%; P < 0.05) and the ratio of inhibitory phosphorylation to total acetyl-CoA carboxylase (46%; P < 0.01), and decreased sterol regulatory element binding protein 1c nuclear translocation by 30% (P < 0.05) in F and SF compared with C rats. Increased phosPck (phoenolpyruvate carboxykinase) (85%) and G6pase(glucose-6-phosphatase) (55%) was observed in S rats (P < 0.05). A 40% decrease in Apob (apolipoprotein B-100) and an increase in hepatic lipids (P < 0.05), together with a double increase in TNF-α (P < 0.001), were observed in S rats, but without liver histopathological changes. These stress effects on lipid accumulation and TNF-α were abolished in SF rats (P < 0.05). CONCLUSIONS: Fructose does not enhance stress effects on hepatic lipid and glucose metabolism but attenuates its effects on hepatic lipid accumulation and inflammation, suggesting that, in female rats, AMPK activation prevails over stress-induced effects.


Assuntos
Frutose , Fígado , Animais , Dieta , Feminino , Frutose/efeitos adversos , Frutose/metabolismo , Lipogênese , Fígado/metabolismo , Ratos , Ratos Wistar
6.
Eur J Nutr ; 58(5): 1829-1845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29845385

RESUMO

PURPOSE: High-fructose consumption and chronic stress are both associated with metabolic inflammation and insulin resistance. Recently, disturbed activity of energy sensor AMP-activated protein kinase (AMPK) was recognized as mediator between nutrient-induced stress and inflammation. Thus, we analyzed the effects of high-fructose diet, alone or in combination with chronic stress, on glucose homeostasis, inflammation and expression of energy sensing proteins in the rat liver. METHODS: In male Wistar rats exposed to 9-week 20% fructose diet and/or 4-week chronic unpredictable stress we measured plasma and hepatic corticosterone level, indicators of glucose homeostasis and lipid metabolism, hepatic inflammation (pro- and anti-inflammatory cytokine levels, Toll-like receptor 4, NLRP3, activation of NFκB, JNK and ERK pathways) and levels of energy-sensing proteins AMPK, SIRT1 and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α). RESULTS: High-fructose diet led to glucose intolerance, activation of NFκB and JNK pathways and increased intrahepatic IL-1ß, TNFα and inhibitory phosphorylation of insulin receptor substrate 1 on Ser307. It also decreased phospho-AMPK/AMPK ratio and increased SIRT1 expression. Stress alone increased plasma and hepatic corticosterone but did not influence glucose tolerance, nor hepatic inflammatory or energy-sensing proteins. After the combined treatment, hepatic corticosterone was increased, glucose tolerance remained preserved, while hepatic inflammation was partially prevented despite decreased AMPK activity. CONCLUSION: High-fructose diet resulted in glucose intolerance, hepatic inflammation, decreased AMPK activity and reduced insulin sensitivity. Chronic stress alone did not exert such effects, but when applied together with high-fructose diet it could partially prevent fructose-induced inflammation, presumably due to increased hepatic glucocorticoids.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Dieta/métodos , Frutose/administração & dosagem , Inflamação/fisiopatologia , Estresse Fisiológico/fisiologia , Animais , Doença Crônica , Modelos Animais de Doenças , Fígado , Masculino , Ratos , Ratos Wistar
7.
Women Health ; 59(9): 1015-1025, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30870132

RESUMO

This study aimed to analyze the measurement properties of the Health-related quality of life questionnaire for polycystic ovary syndrome (PCOSQ-50) in a sample of Serbian women with polycystic ovary syndrome (PCOS). Seventy-six women with PCOS from an endocrinology clinic and 28 healthy women participated between October 2016 and March 2017. The measure was rigorously translated and culturally adapted into Serbian. Psychometric evaluation included descriptive analysis, internal consistency (Cronbach's alpha coefficient), test-retest reliability (intraclass-correlation coefficient - ICC) and construct validity testing. Cronbach's alpha coefficient ranged from 0.67 to 0.96 for domain scales of PCOSQ-50 scores, while the ICCs for test-retest reliability for these domains ranged from 0.66 to 0.89. Women with PCOS had significantly lower scores than healthy women for hirsutism, obesity and menstrual disorders and the total PCOSQ-50 scale score (p ≤ 0.03), but not for the psychosocial and emotional, fertility, sexual function, and coping scales. These results show that the Serbian PCOSQ-50 measure is acceptable and could produce reliable and valid assessments of PCOS-related quality of life for at least four out of seven domains. Considering that validity testing is an iterative process, additional work is needed before the whole measure is used in routine clinical practice.


Assuntos
Síndrome do Ovário Policístico/psicologia , Psicometria/estatística & dados numéricos , Qualidade de Vida/psicologia , Inquéritos e Questionários/normas , Adaptação Psicológica , Adulto , Emoções , Feminino , Humanos , Infertilidade Feminina/complicações , Distúrbios Menstruais/complicações , Questionário de Saúde do Paciente , Síndrome do Ovário Policístico/complicações , Reprodutibilidade dos Testes , Sérvia
8.
Front Endocrinol (Lausanne) ; 15: 1402905, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39268230

RESUMO

Background: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and is closely associated with chronic low-grade inflammation and insulin resistance. To clarify the contribution of prepubertal weight gain to the development of insulin resistance in PCOS, we investigated the effects of early postnatal overfeeding on inflammatory and energy-sensing pathways as well as on markers of insulin signaling in the liver of the PCOS rat model. Methods: Obesity induced by overfeeding was achieved by reducing litter size, while the PCOS-like condition was developed by treatment with 5α-dihydrotestosterone (DHT). Western blot and qPCR were used to analyze the expression of pro-inflammatory transcription factors and cytokines, as well as markers of the energy sensing and insulin signaling pathways. Results: The results showed that hepatic insulin sensitivity was impaired only in DHT-treated rats raised in small litters, as evidenced by increased phosphorylation of IRS1 on Ser307 and decreased expression of total IRS1. Postnatal overfeeding stimulated JNK1 activation independent of hyperandrogenemia; nevertheless, the synergistic effect of both factors triggered NLRP3 activation and increased IL1ß expression in the small litter DHT-treated group. This pro-inflammatory state was accompanied by decreased activatory phosphorylation of AMPK and reduced levels of its protein targets. Conclusions: Overfeeding in the early postnatal period leads to a decrease in hepatic insulin sensitivity in the rat model of PCOS, which is associated with decreased activation of AMPK and stimulation of the hepatic NLRP3-IL1ß signaling pathway. Accordingly, the inhibition of NLRP3 activation could provide a basis for the development of new therapeutic strategies for the treatment of insulin resistance in women with PCOS.


Assuntos
Di-Hidrotestosterona , Modelos Animais de Doenças , Inflamação , Resistência à Insulina , Fígado , Hipernutrição , Síndrome do Ovário Policístico , Animais , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/patologia , Feminino , Ratos , Di-Hidrotestosterona/farmacologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Inflamação/metabolismo , Inflamação/patologia , Hipernutrição/metabolismo , Hipernutrição/complicações , Ratos Wistar , Obesidade/metabolismo , Animais Recém-Nascidos , Transdução de Sinais/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina/metabolismo
9.
Biofactors ; 50(4): 828-844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318672

RESUMO

Obesity is a pressing problem worldwide for which standard therapeutic strategies have limited effectiveness. The use of natural products seems to be a promising approach to alleviate obesity and its associated complications. The tepals of Crocus sativus (Cr) plant, usually wasted in saffron production, are an unexplored source of bioactive compounds. Our aim was to elucidate the mechanisms of Cr tepals extract in obesity by investigating its effects on adipocyte differentiation, visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) hypertrophy, and lipid metabolism in an animal model of diet-induced obesity. To this end, mouse 3T3-F442A preadipocytes were treated with Cr tepals extract and the expression of adipocyte differentiation genes was determined. Caloric intake, body mass, triglycerides, systemic insulin sensitivity, histology, insulin signaling, and lipid metabolism in VAT and SAT were analyzed in mice fed a 60% fat diet for 14 weeks and treated orally with Cr tepals extract during the last 5 weeks of the diet. We demonstrated for the first time that Cr tepals extract inhibits adipocyte differentiation in vitro. The animal model confirmed that oral treatment with Cr tepals extract results in weight loss, improved systemic insulin sensitivity, lower triglycerides, and improved lipid peroxidation. The suppressive effect of Cr tepals extract on adipocyte hypertrophy and inflammation was observed only in SAT, which, together with preserved SAT insulin signaling, most likely contributed to improved systemic insulin sensitivity. Our results suggest the functionality of SAT as a possible target for the treatment of obesity and its complications.


Assuntos
Adipócitos , Crocus , Dieta Hiperlipídica , Resistência à Insulina , Obesidade , Extratos Vegetais , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Extratos Vegetais/farmacologia , Crocus/química , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Masculino , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Obesidade/patologia , Gordura Subcutânea/metabolismo , Gordura Subcutânea/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Hipertrofia/tratamento farmacológico , Camundongos Endogâmicos C57BL , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Adipogenia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos
10.
Biomedicines ; 11(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37371678

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women of reproductive age, often associated with obesity and insulin resistance. Childhood obesity is an important predisposing factor for the development of PCOS later in life. Being particularly interested in the interplay between prepubertal obesity and hyperandrogenemia, we investigated the effects of early postnatal overfeeding, accomplished by reducing litter size during the period of suckling, on energy sensing and insulin signaling pathways in the gastrocnemius muscle of a rat model of PCOS-induced by 5α-dihydrotestosterone (DHT). The combination of overfeeding and DHT treatment caused hyperinsulinemia and decreased systemic insulin sensitivity. Early postnatal overfeeding induced defects at critical nodes of the insulin signaling pathway in skeletal muscle, which was associated with reduced glucose uptake in the presence of hyperandrogenemia. In this setting, under a combination of overfeeding and DHT treatment, skeletal muscle switched to mitochondrial ß-oxidation of fatty acids, resulting in oxidative stress and inflammation that stimulated AMP-activated protein kinase (AMPK) activity and its downstream targets involved in mitochondrial biogenesis and antioxidant protection. Overall, a combination of overfeeding and hyperandrogenemia resulted in a prooxidative and insulin-resistant state in skeletal muscle. This was accompanied by the activation of AMPK, which could represent a potential therapeutic target in insulin-resistant PCOS patients.

11.
Front Nutr ; 9: 899255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677539

RESUMO

Aging is a progressive process that could disturb metabolic homeostasis in the liver via ectopic lipid accumulation, oxidative stress, and deterioration of inflammatory response. Although calorie restriction (CR) is recognized as beneficial for life span and health span prolongation, it is still unclear how late-onset CR, characterized by late beginning and short duration, affects age-related processes. The aim of this study was to examine how late-onset CR-induced metabolic adjustments impact lipid status and inflammation in the liver of old rats. The experiments were conducted on aging male Wistar rats fed ad libitum (AL) or exposed to late-onset CR (60% of AL daily intake) from 21st to 24th month. The results showed that late-onset CR reduces body weight, visceral adipose tissue and liver mass, and triglyceride levels when compared to old animals on AL diet. The ameliorating effects of CR on lipid metabolism include increased activity of AMP-activated protein kinase, suppressed de novo fatty acid synthesis, stimulated ß-oxidation, decreased lipotoxicity, and limited triglyceride synthesis and packaging in the liver. Restricted diet regime, however, does not improve expression of antioxidant enzymes, although it leads to progression of age-related inflammation in the liver, partially through lower corticosterone concentration and decreased activation of glucocorticoid receptor. In conclusion, late-onset CR is able to restore age-related imbalance of lipid metabolism in the liver, but has a negative impact on hepatic inflammatory status, implying that the type of diet for older individuals must be balanced and chosen carefully with appropriate duration and start point.

12.
Sci Total Environ ; 843: 156964, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35764146

RESUMO

Wastewater-based epidemiology (WBE) surveillance of COVID-19 and other future outbreaks is a challenge for developing countries as most households are not connected to a sewerage system. In December 2019, SARS-CoV-2 RNA was detected in the Danube River at a site severely affected by wastewaters from Belgrade. Rivers are much more complex systems than wastewater systems, and efforts are needed to address all the factors influencing the adoption of WBE as an alternative to targeting raw wastewater. Our objective was to provide a more detailed insight into the potential of SARS-CoV-2 surveillance in Serbian surface waters for epidemiological purposes. Water samples were collected at 12 sites along the Sava and Danube rivers in Belgrade during the fourth COVID-19 wave in Serbia that started in late February 2021. RNA was concentrated using Amicon Ultra-15 centrifugal filters and quantified using RT-qPCR with primer sets targeting nucleocapsid (N1 and N2) and envelope (E) protein genes. Microbiological (faecal indicator bacteria and human and animal genetic faecal source tracking markers), epidemiological, physicochemical and hydromorphological parameters were analysed in parallel. From 44 samples, SARS-CoV-2 RNA was detected in 31, but only at 4 concentrations above the level of quantification (ranging from 8.47 × 103 to 2.07 × 104 gc/L). The results indicated that surveillance of SARS-CoV-2 RNA in surface waters as ultimate recipients could be used as an epidemiological early-warning tool in countries lacking wastewater treatment and proper sewerage infrastructure. The performance of the applied approach, including advanced sampling site characterization to trace and identify sites with significant raw sewage influence from human populations, could be further improved by adaptation of the methodology for processing higher volumes of samples and enrichment factors, which should provide the quantitative instead of qualitative data needed for WBE.


Assuntos
COVID-19 , Purificação da Água , COVID-19/epidemiologia , Humanos , RNA Viral , SARS-CoV-2/genética , Águas Residuárias , Vigilância Epidemiológica Baseada em Águas Residuárias
13.
Biofactors ; 47(3): 363-375, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33522030

RESUMO

Dietary fructose can disturb hepatic lipid metabolism in a way that leads to lipid accumulation and steatosis, which is often accompanied with low-grade inflammation. The macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine with important role not only in the regulation of inflammation, but also in the modulation of energy metabolism in the liver. Thus, the aim of this study was to investigate the role of Mif deficiency in fructose-induced disturbances of hepatic lipid metabolism and ectopic lipid accumulation. Wild type (WT) and Mif deficient (MIF-/- ) C57Bl/6J mice were used to analyze the effects of 9-week 20% fructose-enriched diet on hepatic lipid metabolism (both lipogenesis and ß-oxidation) and histology, inflammatory status and glucocorticoid receptor (GR) signaling. The results showed fructose-induced elevation of lipogenic genes (fatty acid synthase (Fas) and stearoyl-CoA desaturase-1 (Scd1) and transcriptional lipogenic regulators (liver X receptor (LXR), sterol regulatory element binding protein 1c (SREBP1c), and carbohydrate response element-binding protein (ChREBP)). However, microvesicular fatty changes, accompanied with enhanced inflammation, were observable only in fructose-fed Mif deficient animals, and were most likely result of GR activation and facilitated uptake and decreased ß-oxidation of FFA, as evidenced by elevated protein level of fatty acid translocase (FAT/CD36) and decreased carnitine palmitoyl transferase 1 (CPT1) level. In conclusion, the results show that Mif deficiency aggravates the effects of energy-rich fructose diet on hepatic lipid accumulation, most likely through enhanced inflammation and activation of GR signaling pathway.


Assuntos
Dieta/métodos , Frutose/metabolismo , Frutose/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fatores Inibidores da Migração de Macrófagos/deficiência , Animais , Lipogênese , Fígado/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais
14.
Front Nutr ; 8: 749328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869524

RESUMO

Introduction: Obesity and related metabolic disturbances are frequently related to modern lifestyle and are characterized by excessive fructose intake. Visceral adipose tissue (VAT) inflammation has a central role in the development of insulin resistance, type 2 diabetes (T2D), and metabolic syndrome. Since sex-related differences in susceptibility and progression of metabolic disorders are not yet fully understood, our aim was to examine inflammation and insulin signaling in VAT of fructose-fed female and male adult rats. Methods: We analyzed effects of 9-week 10% fructose-enriched diet on energy intake, VAT mass and histology, and systemic insulin sensitivity. VAT insulin signaling and markers of VAT inflammation, and antioxidative defense status were also evaluated. Results: The fructose diet had no effect on VAT mass and systemic insulin signaling in the female and male rats, while it raised plasma uric acid, increased PPARγ level in the VAT, and initiated the development of a distinctive population of small adipocytes in the females. Also, adipose tissue insulin resistance, evidenced by increased PTP1B and insulin receptor substrate 1 (IRS1) inhibitory phosphorylation and decreased Akt activity, was detected. In addition, fructose stimulated the nuclear accumulation of NFκB, increased expression of proinflammatory cytokines (IL-1ß, IL-6, and TNFα), and protein level of macrophage marker F4/80, superoxide dismutase 1, and glutathione reductase. In contrast to the females, the fructose diet had no effect on plasma uric acid and VAT inflammation in the male rats, but less prominent alterations in VAT insulin signaling were observed. Conclusion: Even though dietary fructose did not elicit changes in energy intake and led to obesity in the females, it initiated the proliferation of small-sized adipocytes capable of storing fats further. In contrast to the males, this state of VAT was accompanied with enhanced inflammation, which most likely contributed to the development of insulin resistance. The observed distinction could possibly originate from sex-related differences in uric acid metabolism. Our results suggest that VAT inflammation could precede obesity and start even before the measurable increase in VAT mass, making it a silent risk factor for the development of T2D. Our results emphasize that adipose tissue dysfunction, rather than its simple enlargement, could significantly contribute to the onset and development of obesity and related metabolic disorders.

15.
Endocrine ; 72(2): 562-572, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33449293

RESUMO

PURPOSE: Polycystic ovary syndrome (PCOS) is a complex reproductive disorder often associated with obesity, insulin resistance, and dyslipidemia. Hormonal changes in PCOS may also include altered glucocorticoid signaling. Our aim was to examine whether alterations in hepatic glucocorticoid signaling are associated with disturbances of glucose and lipid metabolism in animal model of PCOS. METHODS: Female rats, 3 weeks old, were subcutaneously implanted with 5α-dihydrotestosterone (DHT) or placebo pellets for 90 days to induce PCOS. Expression of 11ß-hydroxysteroid dehydrogenase 1 (11ßHSD1) and A-ring reductases (5α and 5ß), as well as intracellular distribution of glucocorticoid receptor (GR) and expression of its regulated genes were examined in the liver. Proteins of hepatic lipid and carbohydrate metabolism and markers of inflammation were also assessed. RESULTS: DHT treatment induced increase in body and liver mass, as well as in triglycerides and free fatty acids levels in plasma. Elevation of 11ßHSD1 and reduction of 5α-reductase expression was observed together with increased hepatic corticosterone concentration and nuclear GR activation. Induced expression of Krüppel-like factor 15 and decreased expression of genes for proinflammatory cytokines and de novo lipogenesis (DNL) were detected in the liver of DHT-treated rats, while DNL regulators and proinflammatory markers were not changed. However, increased mRNA levels of stearoyl-CoA desaturase and apolipoprotein B were observed in DHT animals. CONCLUSIONS: DHT treatment stimulated hepatic glucocorticoid prereceptor metabolism through increased corticosterone availability which is associated with enhanced GR activation. This does not affect gluconeogenesis and DNL, but could be linked to stimulated triglyceride synthesis and hypertriglyceridemia.


Assuntos
Síndrome do Ovário Policístico , Animais , Di-Hidrotestosterona , Modelos Animais de Doenças , Feminino , Glucocorticoides/metabolismo , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , Ratos , Ratos Wistar
16.
Artigo em Inglês | MEDLINE | ID: mdl-32509596

RESUMO

While gut microbiota dysbiosis has been linked with autism, its role in the etiology of other neurodevelopmental disorders (NDD) is largely underexplored. To our knowledge this is the first study to evaluate gut microbiota diversity and composition in 36 children from the Republic of Serbia diagnosed with NDD and 28 healthy children. The results revealed an increased incidence of potentially harmful bacteria, closely related to Clostridium species, in the NDD patient group compared to the Control group: Desulfotomaculum guttoideum (P < 0.01), Intestinibacter bartlettii (P < 0.05), and Romboutsia ilealis (P < 0.001). On the other hand, significantly lower diversity of common commensal bacteria in the NDD group of patients was noticed. Enterococcus faecalis (P < 0.05), Enterococcus gallinarum (P < 0.01), Streptococcus pasteurianus (P < 0.05), Lactobacillus rhamnosus (P < 0.01) and Bifidobacteria sp. were detected in lower numbers of patients or were even absent in some NDD patients. In addition, butyrate-producing bacteria Faecalibacterium prausnitzii (P < 0.01), Butyricicoccus pullicaecorum (P < 0.05), and Eubacterium rectale (P = 0.07) were less frequent in the NDD patient group. In line with that, the levels of fecal short chain fatty acids (SCFAs) were determined. Although significant differences in SCFA levels were not detected between NDD patients and the Control group, a positive correlation was noted between number of rDNA amplicons obtained with universal primers and level of propionic acid, as well as a trend for levels of total SCFAs and butyric acid in the Control group. This correlation is lost in the NDD patient group, indicating that NDD patients' microbiota differs from the microbiota of healthy children in the presence or number of strong SCFA-producing bacteria. According to a range-weighted richness index it was observed that microbial diversity was significantly lower in the NDD patient group. Our study reveals that the intestinal microbiota from NDD patients differs from the microbiota of healthy children. It is hypothesized that early life microbiome might have an impact on GI disturbances and accompanied behavioral problems frequently observed in patients with a broad spectrum of NDD.


Assuntos
Clostridiales , Disbiose , Microbioma Gastrointestinal , Transtornos do Neurodesenvolvimento , Estudos de Casos e Controles , Criança , Clostridiaceae , Enterococcus , Ácidos Graxos Voláteis , Fezes , Humanos , Transtornos do Neurodesenvolvimento/microbiologia , Streptococcus
17.
Nutrients ; 12(11)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198224

RESUMO

The effects of early-life fructose consumption on hepatic signaling pathways and their relation to the development of metabolic disorders in later life are not fully understood. To investigate whether fructose overconsumption at a young age induces alterations in glucocorticoid signaling that might contribute to development of metabolic disturbances, we analysed glucocorticoid receptor hormone-binding parameters and expression of its target genes involved in gluconeogenesis (phosphoenolpyruvate carboxykinase and glucose-6-phosphatase) and lipid metabolism (lipin-1), as well as redox and inflammatory status in the liver of female rats subjected to a fructose-rich diet immediately after weaning. The fructose diet increased hepatic corticosterone concentration, 11ß-hydroxysteroid dehydrogenase type 1 level, glucocorticoid receptor protein level and hormone-binding activity, as well as lipin-1 level. The expression of glucose-6-phosphatase was reduced in fructose-fed rats, while phosphoenolpyruvate carboxykinase remained unaltered. The fructose-rich diet increased the level of fructose transporter GLUT2, while the expression of fructolytic enzymes fructokinase and aldolase B remained unaltered. The diet also affected pro-inflammatory pathways, but had no effect on the antioxidant defence system. In conclusion, a fructose-rich diet applied immediately after weaning promoted lipogenesis and enhanced hepatic glucocorticoid signaling, possibly to protect against inflammatory damage, but without an effect on gluconeogenesis and antioxidant enzymes. Yet, prolonged treatment might ultimately lead to more pronounced metabolic disturbances.


Assuntos
Carboidratos da Dieta/efeitos adversos , Frutose/administração & dosagem , Glucocorticoides/metabolismo , Lipogênese , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Corticosterona/metabolismo , Feminino , Fígado/metabolismo , Proteínas Nucleares/metabolismo , Ratos , Ratos Wistar , Triglicerídeos/sangue
18.
Exp Gerontol ; 92: 74-81, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28336316

RESUMO

Soy-food and its isoflavones, genistein (G) and daidzein (D), were reported to exert mild cholesterol-lowering effect, but the underlying mechanism is still unclear. In this research, first we studied age-related alterations in hepatic cholesterol metabolism of acyclic middle-aged (MA) female rats. Then we tested if purified isoflavones may prevent or reverse these changes, and whether putative changes in hepatic thyroid hormone availability may be associated with this effect. Serum and hepatic total cholesterol (TChol), bile acid and cholesterol precursors, as well as serum TSH and T4 concentrations, hepatic deiodinase (Dio) 1 enzyme activity and MCT8 protein expression were determined by comparing data obtained for MA with young adult (YA) intact (IC) females. Effects of subcutaneously administered G or D (35mg/kg) to MA rats were evaluated versus vehicle-treated MA females. MA IC females were characterized by: higher (p<0.05) serum TChol, lower (p<0.05) hepatic TChol and its biosynthetic precursors, lower (p<0.05) hepatic 7α-hydroxycholesterol but elevated (p<0.05) 27- and 24-hydroxycholesterol in comparison to YA IC. Both isoflavone treatments decreased (p<0.05) hepatic 27-hydroxycholesterol, G being more effective than D, without affecting any other parameter of Chol metabolism. Only G elevated hepatic Dio1 activity (p<0.05). In conclusion, age-related hypercholesteremia was associated with lower hepatic Chol synthesis and shift from main neutral (lower 7α-hydroxycholesterol) to alternative acidic pathway (higher 27-hydroxycholesterol) of Chol degradation to bile acid. Both isoflavones lowered hepatic 27-hydroxycholesterol, which may be considered beneficial. Only G treatment increased hepatic Dio1 activity, thus indicating local increase in thyroid hormones, obviously insufficient to induce prominent cholesterol-lowering effect.


Assuntos
Envelhecimento , Hidroxicolesteróis/sangue , Isoflavonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Hormônios Tireóideos/sangue , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Hidroxicolesteróis/metabolismo , Fígado/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Fitoestrógenos/farmacologia , Ratos , Ratos Wistar , Glycine max/química
19.
Eur J Endocrinol ; 175(6): 551-560, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27634940

RESUMO

OBJECTIVE: There are limited data on cardiometabolic risk factors and the prevalence of metabolic syndrome (MetS) across the different PCOS phenotypes in Caucasian population. Lipid accumulation product (LAP) is a clinical surrogate marker that could be used for evaluation of MetS in clinical practice. The aim of the study was to analyze metabolic characteristics and the ability of LAP to predict MetS in different PCOS phenotypes. DESIGN: Cross-sectional clinical study analyzing 365 women with PCOS divided into four phenotypes according to the ESHRE/ASRM criteria, and 125 healthy BMI-matched controls. METHODS: In all subjects, LAP was determined and MetS was diagnosed according to the National Cholesterol Education Program/Adult Treatment Panel III (NCEP-ATP III), the International Diabetes Federation (IDF) and the Joint Interim Statement (JIS) criteria. Logistic regression and ROC curve analyses were used to determine predictors of MetS in each PCOS phenotype. All analyses were performed with age and BMI adjustment. RESULTS: All PCOS phenotypes in comparison to controls had higher prevalence of MetS assessed by NCEP-ATP III criteria, and only classic phenotypes when IDF and JIS criteria were used. All phenotypes had the same prevalence of MetS irrespective of used definition. LAP and exhibited the highest diagnostic accuracy and was an independent predictor of MetS in all phenotypes. CONCLUSION: LAP is an independent and accurate clinical determinant of MetS in all PCOS phenotypes in our Caucasian population. All PCOS phenotypes, including non-classic ones, are metabolically challenged and with cardiovascular risk, particularly phenotype B.


Assuntos
Doenças Cardiovasculares/sangue , Produto da Acumulação Lipídica/fisiologia , Síndrome Metabólica/sangue , Fenótipo , Síndrome do Ovário Policístico/sangue , Adulto , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Suscetibilidade a Doenças/sangue , Suscetibilidade a Doenças/diagnóstico , Suscetibilidade a Doenças/epidemiologia , Feminino , Humanos , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/epidemiologia , Adulto Jovem
20.
Hormones (Athens) ; 15(1): 35-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26188230

RESUMO

OBJECTIVE: There is a need for a simple and accurate method for the assessment of cardiovascular risk in polycystic ovary syndrome (PCOS). Lipid accumulation product (LAP) is based on the assessment of waist circumference and serum triglycerides that yield an estimation of lipid overaccumulation. We aimed to determine whether LAP is associated with metabolic syndrome (MetS) in Caucasian women with PCOS. DESIGN: We studied 222 women with PCOS who were diagnosed using the Rotterdam criteria. In all the subjects and controls, LAP was determined and the MetS was assessed using three different international criteria, NCEP-ATP III, IDF, and JIS. ROC curve and logistic regression analyses were performed to determine and analyze associations with the MetS. RESULTS: In the study population the prevalence of MetS was 16.2-19.4%. The cut-off value of 25.9 determined that LAP has the strongest association with MetS whichever international criteria are used, followed by HDL (NCEP-ATP III and JIS) and glucose (IDF). CONCLUSIONS: LAP is used as an independent clinical indicator for MetS in our PCOS women of Caucasian origin. The high diagnostic accuracy of LAP is superseding the need for the use of multiple clinical indicators for the assessment of lipid accumulation as a prerequisite for diagnosis of metabolic and cardiovascular diseases in PCOS women.


Assuntos
Síndrome Metabólica/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Metabolismo dos Lipídeos , Modelos Logísticos , Adulto Jovem
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