RESUMO
Microplastics (MPs) pose a clear threat to aquatic organisms affecting their health. Their impact on liver homeostasis, as well as on the potential onset of nonalcoholic fatty liver disease (NAFLD), is still poorly investigated and remains almost unknown. The aim of this study was to evaluate the outcomes of subchronic exposure to polystyrene MPs (PS-MPs; 1-20 µm; 0, 25, or 250â¯mg/kg b.w./day) on lipid metabolism, inflammation, and oxidative balance in the liver of gilthead seabreams (Sparus aurata Linnaeus, 1758) exposed for 21 days via contaminated food. PS-MPs induced an up-regulation of mRNA levels of crucial genes associated with lipid synthesis and storage (i.e., PPARy, Srebp1, Fasn) without modifications of genes involved in lipid catabolism (i.e., PPARα, HL, Pla2) or transport and metabolism (Fabp1) in the liver. The increase of CSF1R and pro-inflammatory cytokines gene expression (i.e., TNF-α and IL-1ß) was also observed in exposed fish in a dose-dependent manner. These findings were confirmed by hepatic histological evaluations reporting evidence of lipid accumulation, inflammation, and necrosis. Moreover, PS-MPs caused the impairment of the hepatic antioxidant defense system through the alteration of its enzymatic (catalase, superoxide dismutase, and glutathione reductase) and non-enzymatic (glutathione) components, resulting in the increased production of reactive oxygen species (ROS) and malondialdehyde (MDA), as biomarkers of oxidative damage. The alteration of detoxifying enzymes was inferred by the decreased Ethoxyresorufin-O-deethylase (EROD) activity and the increased activity of glutathione-S-transferase (GST) at the highest PS-MP dose. The study suggests that PS-MPs affect the liver health of gilthead seabream. The liver dysfunction and damage caused by exposure to PS-MPs result from a detrimental interplay of inflammation, oxidative damage, and antioxidant and detoxifying enzymatic systems modifications, altering the gut-liver axis homeostasis. This scenario is suggestive of the involvement of MP-induced effects in the onset and progression of hepatic lipid dysfunction in gilthead seabream.
Assuntos
Metabolismo dos Lipídeos , Fígado , Microplásticos , Estresse Oxidativo , Poliestirenos , Dourada , Poluentes Químicos da Água , Animais , Dourada/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Poluentes Químicos da Água/toxicidade , Microplásticos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poliestirenos/toxicidade , Inflamação/induzido quimicamente , Inflamação/patologia , Citocinas/metabolismo , Citocinas/genéticaRESUMO
Sodium valproate (VPA), an antiepileptic drug, may cause dose- and time-dependent hepatotoxicity. However, its iatrogenic molecular mechanism and the rescue therapy are disregarded. Recently, it has been demonstrated that sodium butyrate (NaB) reduces hepatic steatosis, improving respiratory capacity and mitochondrial dysfunction in obese mice. Here, we investigated the protective effect of NaB in counteracting VPA-induced hepatotoxicity using in vitro and in vivo models. Human HepG2 cells and primary rat hepatocytes were exposed to high VPA concentration and treated with NaB. Mitochondrial function, lipid metabolism, and oxidative stress were evaluated, using Seahorse analyzer, spectrophotometric, and biochemical determinations. Liver protection by NaB was also evaluated in VPA-treated epileptic WAG/Rij rats, receiving NaB for 6 months. NaB prevented VPA toxicity, limiting cell oxidative and mitochondrial damage (ROS, malondialdehyde, SOD activity, mitochondrial bioenergetics), and restoring fatty acid oxidation (peroxisome proliferator-activated receptor α expression and carnitine palmitoyl-transferase activity) in HepG2 cells, primary hepatocytes, and isolated mitochondria. In vivo, NaB confirmed its activity normalizing hepatic biomarkers, fatty acid metabolism, and reducing inflammation and fibrosis induced by VPA. These data support the protective potential of NaB on VPA-induced liver injury, indicating it as valid therapeutic approach in counteracting this common side effect due to VPA chronic treatment.
Assuntos
Ácido Butírico/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Anticonvulsivantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/prevenção & controle , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Valproico/farmacologiaRESUMO
Bisphenol A (BPA) as a chemical hazard may enter the milk chain during primary production at the farm and, successively, during milk processing at a dairy company. To identify the potential pathways that play a role in the occurrence of BPA, a monitoring model for risk assessment based on the identification of the hazards at each stage of milk processing was investigated. Milk samples were analyzed using liquid chromatography with fluorescence detection. Quantifiable levels were detected in samples obtained from the raw milk storage tank, pasteurized milk from the storage tank, and packaged milk. The highest BPA contamination levels were detected in raw milk from the storage tank (mean 0.265 µg/L). Despite the fact that dietary exposure levels were below the temporary daily intake, BPA may have adverse effects, particularly for vulnerable population groups. New monitoring programs involving each stage of milk processing should therefore be applied.
Assuntos
Compostos Benzidrílicos , Leite , Animais , Compostos Benzidrílicos/análise , Contaminação de Alimentos/análise , Leite/química , Fenóis/análise , Medição de RiscoRESUMO
Chemical hazards may enter the milk chain during primary production. The study, for the first time, investigated the occurrence of bisphenol A (BPA) levels in cow milk samples collected on the farm following manual or mechanical milking and from the cooling tank. We applied a new monitoring model based on the identification of the hazards at each stage of the milk chain to identify potential pathways for contamination along the milk chain. We evaluated exposure to BPA through milk consumption based on detected contamination levels and the temporary tolerable daily intake established by the European Food Safety Authority (EFSA). Milk samples (n = 72) were analyzed using liquid chromatography with fluorescence detection. The mean BPA concentrations were 0.757 µg/L in manually milked samples, 0.580 µg/L in mechanically milked samples, and 0.797 µg/L in milk from the cooling tank. Bisphenol A occurred in the milk chain as a result of different stages of milking, and reached the highest levels at the end of the milk chain. Although the dietary intake of BPA was below the EFSA's temporary tolerable daily intake, exposure to BPA, even at low doses, through milk consumption represents a public health concern. Therefore, to ensure milk safety, new monitoring plans should be applied based on the identification of hazards at each stage of the milk chain.
Assuntos
Compostos Benzidrílicos/análise , Bovinos , Exposição Dietética , Leite/química , Fenóis/análise , Animais , Cromatografia Líquida , Indústria de Laticínios/métodos , Europa (Continente) , Fazendas , Feminino , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , HumanosRESUMO
Several polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) investigated in soft tissues of the frequently monitored Mytilus galloprovincialis were compared to those of Ensis siliqua, a highly dispersed and economically important bivalve species, though rarely investigated. Overall PCBs had higher concentrations than OCPs in both species with a prevalence of tri- tetra-and penta-chlorinated biphenyls in E. siliqua and a prevalence of hexa- hepta and octa-chlorinated biphenyls in M. galloprovincialis. E. siliqua emerges as a suitable complement to mussels for monitoring PCBs and OCPs pollution.
Assuntos
Bivalves/metabolismo , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/metabolismo , Mytilus/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , AnimaisRESUMO
The study investigated fish welfare at slaughter. Killing animals may induce suffering to the animals even under the best available technical conditions. Moreover, fish have different physiological characteristics and are slaughtered differently from terrestrial animals. The use of commercially available methods exposes farmed fish to pain and suffering during slaughter, which could lead to acute stress and post mortem changes in fish quality. The study aimed to discuss (i) the current knowledge and knowledge gaps on fish welfare related to stunning and killing methods; (ii) the variables that affect the post mortem changes in fish meat, and (iii) the indicators of welfare during slaughter. Application of welfare protocols at slaughter improves fish welfare. Specific protocols for fish are not provided in EC Regulation 1099/2009 on animal protection at killing. Detailed guidelines in the fish welfare assessment may allow the development of specific fish legislation. Developing humane technologies might have important effects on fish quality, consumer perception and aquaculture economics.
RESUMO
Histamine (HIS) intoxication is a poisoning caused by histamine in food. Cheese is one of the most common dairy products associated with histamine levels which vary depending on the processing methods. The final content of histamine in cheese is influenced by intrinsic and extrinsic factors, their interactions, and contamination stemming from food processing. The application of control measures may be useful to inhibit/reduce production during cheese manufacture and processing but have a limited effect. To reduce histamine intoxication outbreaks from cheese consumption the introduction of quality control programs and appropriate risk mitigation options should be applied along the dairy chain from an overall perspective of food safety based on individual susceptibility and consumer sensitivity. As key food safety, this topic should be considered in future regulations in dairy products because the lack of a clear law on HIS limits in cheese may result in a significant potential deviation from the EU food safety strategy.
Assuntos
Queijo , Animais , Queijo/análise , Histamina , Laticínios , Inocuidade dos Alimentos/métodos , Manipulação de Alimentos , Leite , Microbiologia de AlimentosRESUMO
Microplastics (MPs) are pollutants widely distributed in aquatic ecosystems. MPs are introduced mainly by ingestion acting locally or in organs far from the gastroenteric tract. MPs-induced health consequences for fish species still need to be fully understood. We aimed to investigate the effects of the subchronic oral exposure to polystyrene microplastics (PS-MPs) (1-20 µm) in the gilthead seabreams (Sparus aurata) used as the experimental model. We studied the detrimental impact of PS-MPs (25 and 250 mg/kg b.w./day) on the redox balance and antioxidant status in the intestine using histological analysis and molecular techniques. The research goal was to examine the anterior (AI) and posterior intestine (PI) tracts, characterized by morphological and functional differences. PS-MPs caused an increase of reactive oxygen species and nitrosylated proteins in both tracts, as well as augmented malondialdehyde production in the PI. PS-MPs also differently affected gene expression of antioxidant enzymes (i.e., superoxide dismutase, catalase, glutathione reductase). Moreover, an increased up-regulation of protective heat shock proteins (HSPs) (i.e., hsp70 and hsp90) was observed in PI. Our findings demonstrate that PS-MPs are responsible for oxidative/nitrosative stress and alterations of detoxifying defense system responses with differences in AI and PI of gilthead seabreams.
RESUMO
Plastics are the most widely discharged waste into the aquatic ecosystems, where they break down into microplastics (MPs) and nanoplastics (NPs). MPs are ingested by several marine organisms, including benthic and pelagic fish species, contributing to organ damage and bioaccumulation. This study aimed to assess the effects of MPs ingestion on gut innate immunity and barrier integrity in gilthead seabreams (Sparus aurataLinnaeus, 1758) fed for 21 days with a diet enriched with polystyrene (PS-MPs; 1-20 µm; 0, 25 or 250 mg /kg b.w./die). Physiological fish growth and health status were not impacted by PS-MPs treatments at the end of experimental period. Inflammation and immune alterations were revealed by molecular analyses in both anterior (AI) and posterior intestine (PI) and were confirmed by histological evaluation. PS-MPs triggered TLR-Myd88 signaling pathway with following impairment of cytokines release. Specifically, PS-MPs increased pro-inflammatory cytokines gene expression (i.e., IL-1ß, IL-6 and COX-2) and decreased anti-inflammatory ones (i.e., IL-10). Moreover, PS-MPs also induced an increase in other immune-associated genes, such as Lys, CSF1R and ALP. TLR-Myd88 signaling pathway may also lead to the mitogen-activated protein kinases (MAPK) signaling pathway activation. Here, MAPK (i.e., p38 and ERK) were activated by PS-MPs in PI, following the disruption of intestinal epithelial integrity, as evidenced by reduced gene expression of tight junctions (i.e. ZO-1, Cldn15, Occludin, and Tricellulin), integrins (i.e., Itgb6) and mucins (i.e., Muc2-like and Muc13-like). Thus, all the obtained results suggest that the subchronic oral exposure to PS-MPs induces inflammatory and immune alterations as well as an impact on intestinal functional integrity in gilthead seabream, with a more evident effect in PI.
Assuntos
Dourada , Animais , Microplásticos/toxicidade , Poliestirenos/toxicidade , Plásticos , Ecossistema , Fator 88 de Diferenciação Mieloide , Imunidade , Citocinas , IntestinosRESUMO
We investigated the occurrence of organochlorine pollutants (OCs) in the muscle of brown trout and evaluated their potential modulation of parasite infection. The toxicological risk for consumer health was assessed, too. Trout were collected from the Sila National Park (Calabria region, South of Italy). The highest concentrations emerged for the sum of the 6 non-dioxin-like (ndl) indicator polychlorinated biphenyls (Σ6ndl-PCBs), followed by the 1,1,1-trichloro-2,2-di(4-chlorophenyl)-ethane (DDT), dioxin-like PCBs, hexachlorobenzene (HCB), and dieldrin. Measured on lipid weight (LW), the mean value of Σ6ndl-PCBs amounted to 201.9 ng g-1, that of ΣDDTs (the sum of DDT-related compounds) to 100.2 ng g-1, with the major contribution of the DDT-metabolite p,p'-DDE which was detected in all sample units (97.6 ng g-1 on average). Among dioxin-like congeners, PCB 118 showed the highest mean concentration (21.96 ng g-1 LW) and was detected in all sample units. Regression analysis of intestinal parasites on OC concentration was performed, controlling for two potential confounding factors, namely sex and sexual stage. The results evidenced the existence of interactions between the dual stressors in the host-parasite system in the wild. A negative and statistically significant correlation was estimated, suggesting that OCs may decrease parasite infection degree. Regarding the toxicological risk evaluation, OC concentrations were consistently below the current European Maximum Residue Limits.
RESUMO
Micro- and nanoplastics (MPs/NPs) are among the most widely distributed pollutants in the environment. It has been suggested that exposure to MPs/NPs can trigger toxicity pathways among which inflammation and oxidative stress (OS) play a pivotal role. Once absorbed, MPs/NPs may act locally or access the bloodstream and, following the translocation process, reach several organs and tissues, including the gonads. Notably, MPs/NPs can bioaccumulate in human and murine placenta, opening new scenarios for toxicological evaluations. We review recent studies on the effects of MPs/NPs on the reproductive health in aquatic and terrestrial organisms of both sexes, focusing on the role of OS and the antioxidant defence system failure as the main underlying mechanisms. Alterations in gametogenesis, embryonic and offspring development, and survival have been shown in most studies and often related to a broken redox balance. All these detrimental effects are inversely related to particle size, whereas they are closely linked to shape, plastic polymer type, superficial functionalization, concentration, and time of exposure. To date, the studies provide insights into the health impacts, but no conclusions can be drawn for reproduction toxicity. The main implication of the few studies on antioxidant substances reveals their potential role in mitigating MP-induced toxic effects.
RESUMO
The potential role of brown and beige adipose tissue against obesity has been recognized. Browning, or beiging of white adipose tissue (WAT) is associated with the remodeling of adipocytes and the improvement of their metabolic and secretory functions. Here, palmitoylethanolamide (PEA) restore the plasticity of brown and white adipocytes impaired in mice on a high-fat diet (HFD). Young male C57Bl/6J mice were fed with control (STD) diet or HFD for 12 weeks. Ultramicronized PEA (30 mg/kg/die p.o.) was administered for an additional 7 weeks, together with HFD. PEA recovered interscapular brown fat morphology and function, increasing UCP1 positivity, noradrenergic innervation, and inducing the mRNA transcription of several specialized thermogenic genes. PEA promotes the beige-conversion of the subcutaneous WAT, increasing thermogenic markers and restoring leptin signaling and tissue hormone sensitivity. The pivotal role of lipid-sensing peroxisome proliferator-activated receptor (PPAR)-α in PEA effects was determined in mature 3T3-L1. Moreover, PEA improved mitochondrial bioenergetics in mature adipocytes measured by a Seahorse analyzer and induced metabolic machinery via AMPK phosphorylation. All these outcomes were dampened by the receptor antagonist GW6471. Finally, PEA induced adipogenic differentiation and increased AMPK phosphorylation in human adipose-derived stromal cells (ASCs) obtained from subcutaneous WAT of normal-weight patients and patients with obesity. We identify PEA and PPAR-α activation as the main mechanism by which PEA can rewire energy-storing white into energy-consuming brown-like adipocytes via multiple and converging effects that restore WAT homeostasis and metabolic flexibility.
RESUMO
The occurrence of analogues of bisphenol A (BPA), including bisphenol F(BPF) in milk is still not well known. BPF may enter the milk chain at the farm and during milk processing at the dairy company. This study identified the main BPF contamination pathways using a monitoring model based on the identification of the hazard at three stages along the dairy chain: raw milk from the storage tank, pasteurized milk from the storage tank, and cardboard packaged milk. Quantitative analysis was performed by high-performance liquid chromatography with fluorometric detection (HPLC/FD) system. BPF was detected in all analysed stages (from Assuntos
Compostos Benzidrílicos/análise
, Disruptores Endócrinos/análise
, Contaminação de Alimentos/análise
, Leite/química
, Fenóis/análise
, Animais
, Manipulação de Alimentos
, Embalagem de Alimentos
, Inocuidade dos Alimentos
, Humanos
, Pasteurização
, Medição de Risco
RESUMO
Bisphenol F (BPF) is a bisphenol A (BPA) analogue. As an endocrine disruptor, BPF shows a similar BPA hormonal activity and greater endocrine effects. To assess BPF levels in milk a selective method based on solvent extraction with acetonitrile, solid-phase extraction (SPE), high-performance liquid chromatography with fluorescence detection (HPLC-FD) system, was developed. The method showed high recovery values (from 97.60 to 107.16%), and good detection and quantification limits (LOD=0.03 µg/L; LOQ=0.1 µg/L). To validate the analytical method, quantitative analyses of n.20 milk samples of whole milk were preliminarily carried out applying a monitoring system based on the control of different stages of pasteurized whole milk processing at a dairy company. The proposed method is simple, sensitive, and might be suitable to detect BPF residues in milk processing. At the dairy company, the occurrence of BPF levels ranging from
RESUMO
Bisphenol A (BPA) is a non-persistent anthropic and environmentally ubiquitous compound widely employed and detected in many consumer products and food items; thus, human exposure is prolonged. Over the last ten years, many studies have examined the underlying molecular mechanisms of BPA toxicity and revealed links among BPA-induced oxidative stress, male and female reproductive defects, and human disease. Because of its hormone-like feature, BPA shows tissue effects on specific hormone receptors in target cells, triggering noxious cellular responses associated with oxidative stress and inflammation. As a metabolic and endocrine disruptor, BPA impairs redox homeostasis via the increase of oxidative mediators and the reduction of antioxidant enzymes, causing mitochondrial dysfunction, alteration in cell signaling pathways, and induction of apoptosis. This review aims to examine the scenery of the current BPA literature on understanding how the induction of oxidative stress can be considered the "fil rouge" of BPA's toxic mechanisms of action with pleiotropic outcomes on reproduction. Here, we focus on the protective effects of five classes of antioxidants-vitamins and co-factors, natural products (herbals and phytochemicals), melatonin, selenium, and methyl donors (used alone or in combination)-that have been found useful to counteract BPA toxicity in male and female reproductive functions.
RESUMO
Lines of evidence have shown the embryogenic and transgenerational impact of bisphenol A (BPA), an endocrine-disrupting chemical, on immune-metabolic alterations, inflammation, and oxidative stress, while BPA toxic effects in adult obese mice are still overlooked. Here, we evaluate BPA's worsening effect on several hepatic maladaptive processes associated to high-fat diet (HFD)-induced obesity in mice. After 12 weeks HFD feeding, C57Bl/6J male mice were exposed daily to BPA (50 µg/kg per os) along with HFD for 3 weeks. Glucose tolerance and lipid metabolism were examined in serum and/or liver. Hepatic oxidative damage (reactive oxygen species, malondialdehyde, antioxidant enzymes), and mitochondrial respiratory capacity were evaluated. Moreover, liver damage progression and inflammatory/immune response were determined by histological and molecular analysis. BPA amplified HFD-induced alteration of key factors involved in glucose and lipid metabolism, liver triglycerides accumulation, and worsened mitochondrial dysfunction by increasing oxidative stress and reducing antioxidant defense. The exacerbation by BPA of hepatic immune-metabolic dysfunction induced by HFD was shown by increased toll-like receptor-4 and its downstream pathways (i.e., NF-kB and NLRP3 inflammasome) amplifying inflammatory cytokine transcription and promoting fibrosis progression. This study evidences that BPA exposure represents an additional risk factor for the progression of fatty liver diseases strictly related to the cross-talk between oxidative stress and immune-metabolic impairment due to obesity.
RESUMO
The aim of the study is to investigate the potential relationship between exposure to PCBs and cancer. In doing so we relied on a sample of dogs coming from a peculiar area of the Campania region (Italy), that has been suffering for illegal waste dumping and open air burning of plastic waste for many years. The latter determined the release of organic and inorganic pollutants, such as the PCBs. By comparing dogs with cancer and healthy dogs, we found much higher PCB concentrations in the former, with a significant difference (p < 0.05) for the non-indicator ∑10NDL-PCB and the DL-PCBs. A regression analysis, controlling for three potentially confounding factors, that are sex, age and weight, confirmed the higher ∑10NDL-PCB concentration in dogs with cancer. Hence, our evidence suggests a potential health hazard for animals and likewise people living in a risky area due to the presence of environmental organic pollutants.
Assuntos
Tecido Adiposo/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Bifenilos Policlorados/metabolismo , Instalações de Eliminação de Resíduos , Tecido Adiposo/química , Animais , Cães , Poluentes Ambientais/análise , Feminino , Humanos , Itália , Masculino , Plásticos , Bifenilos Policlorados/análiseRESUMO
Diet represents the primary route for human exposure to bisphenol A (BPA). As endocrine disruptor (ED), BPA has raised concerns about its adverse effects on human health. Therefore, EFSA recommended a tolerable daily intake (t-TDI) of 4 µg/kg bw/day and the EU Regulation n. 2018/213 fixed a specific migration limit (SML) of 0.05 mg/kg for BPA in food from plastic materials intended to come in contact with food. BPA could be present in milk due to environmental contamination, and also as a result of the migration from contact materials used during milking and storage. Considering the widespread consumption of milk and milk products, the contamination of dairy products is a matter of public health concern. The aim of the study was to investigate the BPA contamination levels of raw cow's milk from two farms located in Campania region, Italy. The milk samples (n=22), weekly collected from the cooling tank, were analyzed using liquid chromatography with fluorescence detection. In raw milk from both farms, preliminary results showed the occurrence of BPA levels lower than the SML limit, ranging from not detected to 2.34 µg/L. The consumer exposure, calculated considering a hypothetical raw milk consumption and three possible scenarios, was below the t-TDI. Despite the low levels of exposure through milk consumption, low doses can have lasting effects during human development. Thus, new approaches, methods, and plans should be applied to monitor ED contamination, such as BPA and other pollutants, and to assure milk safety.
RESUMO
Leptin and/or ghrelin, initially thought to be considered messengers of energy metabolism, are now considered to play a role in normal and complicated pregnancy. In this study, pregnant, spontaneously hypertensive rats (SHR) have been used to evaluate, for the first time, the modification of leptin and ghrelin both at serum and tissue levels. In SHR, we evaluate plasma leptin level and tissue protein expression in both placenta and adipose tissue at the end of gestation (day 20) versus normotensive Wistar-Kyoto (WKY) animals. The expression of functional leptin receptor (Ob-Rb) in peripheral tissues and in the hypothalamus was evaluated. Moreover, we measured plasma ghrelin level and its mRNA expression in the stomach and placenta. SHR strain presented significantly lower plasma leptin levels when compared with those found in pregnant or not WKY controls. Interestingly, in the placenta, leptin gene expression was higher in SHR than normotensive WKY. Moreover, we demonstrated a resistance to the effects of leptin via 'downregulation' of hypothalamic receptors in pregnant SHR. Conversely, SHR presented significantly higher ghrelin plasma levels when compared with those found in pregnant or not WKY. However, we observed that ghrelin level in the stomach of SHR did not change during pregnancy, and on the opposite, mRNA ghrelin in the placenta of SHR was lower than that of normotensive rats, suggesting a different production of this hormone in the fetal-placental unit. These data gain further insight into metabolic hormone modifications observed in a model of pre-existing hypertension associated with pregnancy.
Assuntos
Adaptação Fisiológica , Grelina/sangue , Hipertensão/metabolismo , Leptina/sangue , Complicações Cardiovasculares na Gravidez/metabolismo , Tecido Adiposo/química , Animais , Feminino , Expressão Gênica , Grelina/análise , Grelina/genética , Hipotálamo/química , Leptina/análise , Modelos Animais , Obesidade/metabolismo , Placenta/química , Gravidez , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores para Leptina/análise , Receptores para Leptina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estômago/químicaRESUMO
Seven target polychlorinated biphenyls (PCBs; IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) and the organochlorine pesticides (OCPs) hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane (DDT) and its related metabolites (p,p'-DDT, p,p'-DDE, and p,p'-DDD) were quantified in edible tissues from seven marine species (European hake, red mullet, blue whiting, Atlantic mackerel, blue and red shrimp, European flying squid, and Mediterranean mussel) from the Gulf of Naples in the southern Tyrrhenian Sea (Italy). PCBs 118, 138, and 153 were the dominant congeners in all the species examined. The concentrations of all PCBs (from not detectable to 15,427 ng g(-1) fat weight) exceeded those of all the DDTs (from not detectable to 1,769 ng g(-1) fat weight) and HCB (not detectable to 150.60 ng g(-1) fat weight) in the samples analyzed. The OCP concentrations were below the maximum residue limits established for fish and aquatic products by the Decreto Ministerale 13 May 2005 in all the samples analyzed; therefore the OCPs in the southern Tyrrhenian Sea species are unlikely to be a significant health hazard. Conversely, the mean concentrations of PCBs exceeded (greatly in some cases) the current limits (200 ng(-1) fat weight) set by the European Union for terrestrial foods. Although the manufacture and use of PCBs are banned or highly restricted, these compounds still are important persistent chemical contaminants in the Gulf of Naples.