RESUMO
INTRODUCTION: Uremic toxicity changes the gut structure and permeability, allowing bacterial toxins to translocate from the lumen to the blood during chronic kidney failure (CKD). Clinical fluid overload and tissue edema without uremia have similar effects but have not been adequately demonstrated and analyzed in CKD. AIMS: To investigate the effect of sodium intake on the plasma concentration of gut-derived uremic toxins, indoxyl sulfate (IS), and p-cresyl sulfate (pCS) and the expression of genes and proteins of epithelial gut tight junctions in a rat model of CKD. METHODS: Sham-operated (control group, CG) and five-sixths nephrectomized (5/6Nx) Sprague-Dawley rats were randomly assigned to low (LNa), normal (NNa), or high sodium (HNa) diets., Animals were then sacrificed at 8 and 12 weeks and analyzed for IS and pCS plasma concentrations, as well as for gene and protein expression of thigh junction proteins, and transmission electron microscopy (TEM) in colon fragments. RESULTS: The HNa 5/6Nx groups had higher concentrations of IS and pCS than CG, NNa, and LNa at eight and twelve weeks. Furthermore, HNa 5/6Nx groups had reduced expression of the claudin-4 gene and protein than CG, NNa, and LNa. HNa had reduced occludin gene expression compared to CG. Occludin protein expression was more reduced in HNa than in CG, NNa, and LNa. The gut epithelial tight junctions appear dilated in HNa compared to NNa and LNa in TEM. CONCLUSION: Dietary sodium intake and fluid overload have a significant role in gut epithelial permeability in the CKD model.
Assuntos
Toxinas Bacterianas , Insuficiência Renal Crônica , Sódio na Dieta , Ratos , Animais , Ratos Sprague-Dawley , Ocludina/genética , Ocludina/metabolismo , Junções Íntimas , Toxinas Bacterianas/metabolismo , Indicã , Sódio na Dieta/metabolismo , PermeabilidadeRESUMO
Daily, people are exposed to chemicals and environmental compounds such as bisphenols (BPs). These substances are present in more than 80% of human fluids. Human exposure to BPs is associated with male reproductive health disorders. Some of the main targets of BPs are intercellular junction proteins of the blood-testis barrier (BTB) in Sertoli cells because BPs alter the expression or induce aberrant localization of these proteins. In this systematic review, we explore the effects of BP exposure on the expression of BTB junction proteins and the characteristics of in vivo studies to identify potential gaps and priorities for future research. To this end, we conducted a systematic review of articles. Thirteen studies met our inclusion criteria. In most studies, animals treated with bisphenol-A (BPA) showed decreased occludin expression at all tested doses. However, bisphenol-AF treatment did not alter occludin expression. Cx43, ZO-1, ß-catenin, nectin-3, cortactin, paladin, and claudin-11 expression also decreased in some tested doses of BP, while N-cadherin and FAK expression increased. BP treatment did not alter the expression of α and γ catenin, E-cadherin, JAM-A, and Arp 3. However, the expression of all these proteins was altered when BPA was administered to neonatal rodents in microgram doses. The results show significant heterogeneity between studies. Thus, it is necessary to perform more research to characterize the changes in BTB protein expression induced by BPs in animals to highlight future research directions that can inform the evaluation of risk of toxicity in humans.
Assuntos
Barreira Hematotesticular , Células de Sertoli , Animais , Recém-Nascido , Masculino , Humanos , Barreira Hematotesticular/metabolismo , Ocludina/metabolismo , Ocludina/farmacologia , Células de Sertoli/metabolismo , Junções IntercelularesRESUMO
OBJECTIVE: The study aimed to investigate the feasibility of establishing rhinosinusitis model in rats combinated with Lipopolysaccharide (LPS) and merocel sponge. METHODS: SD (Sprague Dawley) rats that underwent nasal obstruction using Merocel sponge packing, rats with LPS instillation alone, and rats with both nasal obstruction and LPS instillation were used to establish rat models of rhinosinusitis. After the models were established, the nasal symptoms of rats were recorded, the histopathological examination and Transmission Electron Microscopy (TME) of the sinus tissue were performed and the levels of Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6) in the blood were also analyzed. The expressions of Aquaporin-5 (AQP5), Occludin, Toll-Like Receptor-4 (TLR4), Medullary differentiation factor 88 (MyD88) and phosphorylated (p)-p65 protein were detected by Western blot to evaluate the effect and mechanism of the experimental models. RESULTS: We found that compared with the control group and LPS group, the sinusitis symptom scores in the Merocel sponge combined with LPS group were significantly increased; the respiratory epithelia of the maxillary sinus were degenerated, cilia were detached, and even inflammatory cell infiltration occurred; the levels of TNF-α and IL-6 were increased; the expression of AQP5 and Occludin protein was decreased; and the expressions of TLR4, MyD88, and p-p65 protein were increased. CONCLUSION: For the first time, we successfully established a rat rhinosinusitis model using Merocel sponge with LPS and explored the possible mechanism of LPS action.
Assuntos
Obstrução Nasal , Sinusite , Ratos , Animais , Ratos Sprague-Dawley , Lipopolissacarídeos/farmacologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Interleucina-6 , Fator de Necrose Tumoral alfa , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Ocludina/metabolismo , Ocludina/farmacologia , Sinusite/induzido quimicamenteRESUMO
PURPOSE: Abnormal activation of NOD-like receptor protein 3 (NLRP3) inflammasome can lead to the occurrence and progression of acute pancreatitis. This study investigated the protective effect of MCC950 on pancreatitis mice. METHODS: Eighteen mice were randomly divided into control group, severe acute pancreatitis (SAP) group and SAP+MCC950 group. Serum interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α) were measured by ELISA. Hematoxylin and eosin (HE) staining was used to evaluate the pathological damage. Western blotting was used to detect the expression of NLRP3 inflammasome and tight junction proteins in the small intestine and pancreas. RESULTS: MCC950 could reduce the levels of IL-6 and IL-1ß in SAP mice. After treatment with MCC950, the expression levels of NLRP3 inflammasome in the pancreas of SAP mice were significantly reduced and the pathological damage to the pancreas and intestine was alleviated. Compared with the control group, the expression of tight junction protein (ZO-1,occludin and claudin-4) in the intestinal mucosa of SAP mice was decreased, and the expression of claudin-4 and occludin were upregulated after MCC950 treatment. CONCLUSIONS: MCC950 can inhibit NLRP3 inflammasome activation and significantly reduce the inflammatory response and delay the process of pancreatitis. It has therapeutic potential in the treatment of acute pancreatitis.
Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Pancreatite , Animais , Camundongos , Doença Aguda , Claudina-4/metabolismo , Inflamassomos/metabolismo , Interleucina-6 , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ocludina/metabolismo , Pancreatite/tratamento farmacológico , Pancreatite/fisiopatologiaRESUMO
Background: Intestinal mucositis is one of the most common and important side effects of 5-fluorouracil (5-FU). Currently, there are still no specific and effective protocols for its prevention and treatment. The aim of the present study was to evaluate the effect of oral administration of Lacticaseibacillus casei (L. casei) on the progression of 5-FU-induced intestinal mucositis. Methods: L. casei (1x109 CFU/ml) or saline was orally administered to Swiss mice, beginning 15 days before intestinal mucositis induction by single intraperitoneal 5-FU administration (450 mg/kg). Body weight, number of peripheral leukocytes and fecal lactic acid bacteria were monitored. After euthanasia, on day 18, tissue samples from colon and each small intestine segment were collected for histopathology. Jejunal tissues were collected and evaluated for iNOS and TNF-alpha immunoexpression, IL-1-beta, IL-6 and TNF-alpha levels, malonaldehyde (MDA) accumulation, invertase activity and factor nuclear kappa B (NFkB-P65) gene expression, toll like receptor-4 (TLR-4), mucin-2 (MUC-2), occludin and zonula occludens-1 (ZO-1). Results: The positive impact of L. casei on 5-FU-induced leukopenia was observed, but not on 5-FU-induced weight loss in mice. L. casei reduced 5-FU-induced inflammation in the colon and small intestine (p<0.05). Decreased TNF-α, IL-1ß, IL-6 (p<0.05) and MDA (p<0.05) levels, as well as decreased iNOS and TNF-alpha protein expressions (p<0.05) were found in the jejunum from L casei group. In addition, L-casei down-regulated NFKB-P65 (p<0.05) and TLR-4 (p<0.05) gene expressions and up-regulated MUC-2 and mucosal barrier proteins occludin and ZO-1 gene expressions (p<0.05). Furthermore, greater lactic acid bacteria population (p<0.05) was found in the L. casei group when compared to control groups. Conclusion: Oral L. casei administration can protect the intestine of Swiss mice from 5-FU-induced intestinal mucositis, thus contributing to overall health.
Assuntos
Lacticaseibacillus casei , Mucosite , Camundongos , Animais , Fluoruracila/farmacologia , Mucosite/induzido quimicamente , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Ocludina/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Colo/patologiaRESUMO
Enteric glial cells (EGCs) constitute the majority of the neural population of the enteric nervous system and are found in all layers of the gastrointestinal tract. It is active in enteric functions such as immunomodulation, participating in inflammation and intestinal epithelial barrier (IEB) regulation. Both EGCs and IEB have been described as altered in Parkinson's disease (PD). Using an animal model of PD induced by 6-hydroxydopamine (6-OHDA), we investigated the effect of ongoing neurodegeneration on EGCs and inflammatory response during short periods after model induction. C57Bl/6 male mice were unilaterally injected with 6-OHDA in the striatum. Compared to the control group, 6-OHDA animals showed decreased relative water content in their feces from 1 w after model induction. Moreover, at 1 and 2 w post-induction, groups showed histopathological changes indicative of intestinal inflammation. We identified an increase in IBA1 and GFAP levels in the intestinal mucosa. At an earlier survival of 48 h, we detected an increase in GFAP in the neuromuscular layer, suggesting that it was a primary event for the upregulation of GDNF, TNF-α, and occludin in the intestinal mucosa observed after 1 w. Within 2 w, we identified a decrease in the expression of occludin barrier proteins. Thus, EGCs modulation may be an early enteric signal induced by parkinsonian neurodegeneration, followed by inflammatory and dysmotility signs besides IEB modification.
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Sistema Nervoso Entérico , Doença de Parkinson , Animais , Modelos Animais de Doenças , Sistema Nervoso Entérico/metabolismo , Inflamação/metabolismo , Masculino , Camundongos , Neuroglia/metabolismo , Ocludina/metabolismo , Oxidopamina/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson/metabolismoRESUMO
BACKGROUND: Metastasis is the worst prognostic variable of patients with colorectal cancer (CRC). For the development of metastases, it is necessary that cancer cells detach from the primary tumor, migrate into the angiolymphatic system, and invade the tissue where they will develop. The breakdown of the tight junctions (TJs) plays an important role in colorectal metastatic tumors. Claudin-3 and occludin are the main component proteins of TJs. AIM: To analyze the expression and tissue content of claudin-3 and occludin in normal and neoplastic tissues of patients with metastatic CRC. METHODS: Fifty-seven consecutive patients with stage III and IV CRC were included. Fragments of neoplastic tissue were collected from the tumor margins, and samples of the normal tissue were collected from the same patient in a standardized distance of 10 cm from the cranial margin of the tumor. Immunohistochemistry technique was used to identify the tissue staining of claudin-3 and occludin. To measure the content of both proteins in cellular membranes of normal and cancer cells, a validated immunoscore was used. RESULTS: Claudin-3 and occludin in normal tissues are in the apical and lateral membranes of cells, while in the neoplastic, in cytoplasm. The mean of the tissue content of claudin-3 in the normal tissue was 2.57 ± 0.16, while in the neoplastic tissue was 1.03 ± 0.13. The contents of occludin were 2.77 ± 0.1 in normal tissue, while in the neoplastic were 1.08 ± 0.14. CONCLUSION: There is a reduction in the content of the claudin-3 and occludin in the cell membranes of the neoplastic tissue in patients with CRC.
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Neoplasias Colorretais , Junções Íntimas , Humanos , Ocludina/análise , Ocludina/metabolismo , Claudina-3/análise , Claudina-3/metabolismo , Claudina-1/análise , Claudina-1/metabolismo , Junções Íntimas/química , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Neoplasias Colorretais/patologiaRESUMO
Bisphenols are a group of environmental endocrine-disrupting chemicals that produce alterations in the expression of intercellular junction proteins of the Blood-Testis Barrier (BTB) involved in spermatogenesis. The association between bisphenol exposure and BTB protein expression is controversial. Therefore, we performed this systematic review and meta-analysis to clarify bisphenol effects on Sertoli cell BTB protein expression in vitro. The Standardized Mean Difference (SMD) with a 95 % confidence interval (95 % CI) was used to evaluate the association between alterations in the BTB protein expression and bisphenol exposure in vitro. Six articles were included in the meta-analysis. Bisphenol-A (BPA) exposure at 200⯵M was associated with significant decrease in BTB protein expression (SMDâ¯=â¯-2.70, 95 %CI: -3.59, -1.80, p hetâ¯=â¯0.46, pâ¯=â¯<0.00001). In the moderate (40-50⯵M) and low dose (<25⯵M), no significant associations were obtained. We also found a non-monotonic dose-response curve of bisphenol effect in ZO-1 protein expression; low and high doses presented a significant decrease compared to control, while moderate dose presented no change. The current temporary Tolerable Daily Intake (tTDI) of BPA is 4⯵g/kg bw/day. The 5-25⯵M doses of BPA are equivalent to â¼1-5â¯mg/kg bw, respectively. Although the low dose group (<25⯵M) assessed doses below the previous NOAEL value, these doses are above the current tTDI. Thus, it is necessary to conduct more studies with lower bisphenol concentrations to avoid underestimating the potential adverse effects of bisphenols at doses below tTDI.
Assuntos
Compostos Benzidrílicos/toxicidade , Barreira Hematotesticular/efeitos dos fármacos , Fenóis/toxicidade , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Humanos , Junções Intercelulares/efeitos dos fármacos , Masculino , Ocludina/metabolismo , Proteínas/metabolismo , Células de Sertoli/efeitos dos fármacos , Espermatogênese , Testículo/efeitos dos fármacos , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
It has been postulated that glyphosate (G) or its commercial formulation Roundup (R) might lead to male fertility impairment. In this study, we investigated the possible effects of G or R treatment of juvenile male rats on blood-testis barrier function and on adult male sperm production. Pups were randomly assigned to the following groups: control group (C), receiving water; G2 and G50 groups, receiving 2 and 50 mg/kg/day G respectively; and R2 and R50 groups receiving 2 and 50 mg/kg/day R respectively. Treatments were performed orally from postnatal day (PND) 14 to 30, period of life that is essential to complete a functional blood-testis barrier. Evaluation was done on PND 31. No differences in body and testis weight were observed between groups. Testis histological analysis showed disorganized seminiferous epithelium, with apparent low cellular adhesion in treated animals. Blood-testis barrier permeability to a biotin tracer was examined. A significant increase in permeable tubules was observed in treated groups. To evaluate possible mechanisms that could explain the effects on blood-testis barrier permeability, intratesticular testosterone levels, androgen receptor expression, thiobarbituric acid reactive substances (TBARS) and the expression of intercellular junction proteins (claudin11, occludin, ZO-1, connexin43, 46, and 50 which are components of the blood-testis barrier) were examined. No modifications in the above-mentioned parameters were detected. To evaluate whether juvenile exposure to G and R could have consequences during adulthood, a set of animals of the R50 group was allowed to grow up until PND 90. Histological analysis showed that control and R50 groups had normal cellular associations and complete spermatogenesis. Also, blood-testis barrier function was recovered and testicular weight, daily sperm production, and epididymal sperm motility and morphology did not seem to be modified by juvenile treatment. In conclusion, the results presented herein show that continuous exposure to low doses of G or R alters blood-testis barrier permeability in juvenile rats. However, considering that adult animals treated during the juvenile stage showed no differences in daily sperm production compared with control animals, it is feasible to think that blood-testis barrier impairment is a reversible phenomenon. More studies are needed to determine possible damage in the reproductive function of human juvenile populations exposed to low doses of G or R.
Assuntos
Barreira Hematotesticular/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Barreira Hematotesticular/metabolismo , Claudinas/metabolismo , Conexinas/metabolismo , Glicina/administração & dosagem , Masculino , Ocludina/metabolismo , Ratos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , GlifosatoRESUMO
Obesity is associated with cognitive deficit and liver alterations; however, it remains unclear whether a combination of functional foods could reverse cognitive damage and to what extent it would be associated with changes in gut microbiota and liver. With this aim, male Wistar rats were fed a high-fat-5%sucrose diet (HFS) for 4 mo. And were then fed for 1 mo. with bioactive foods. At the end of this period, liver, serum, feces, intestine, and brain samples were taken. Body composition, energy expenditure, LPS, hormones, intraperitoneal glucose tolerance test, behavioral tests, and gut microbiota were evaluated. We showed that male rats fed high-fat-sucrose diet developed gut microbiota dysbiosis, increased in body fat, decreased antioxidant activity, decreased brain neuropeptide Y, increased the number of astrocytes and activated microglia, along with reduced spine density associated with deficits in working memory. Ingestion of a combination of nopal, soy protein, curcumin, and chia seed oil (bioactive foods) for three months was associated with an increase in a cluster of bacteria with anti-inflammatory capacity, a decrease in serum LPS levels and an increase in serum eicosapentaenoic acid (EPA) with neuroprotective properties. In the liver, ingestion of bioactive food significantly increased antioxidant enzymes, decreased lipogenesis, reduced inflammation mediated by the TLR4-TNFα pathway along with a decrease in body fat, glucose intolerance, and metabolic inflexibility. Finally, neuroinflammation in the brain was reduced and working memory improved. Our study demonstrates that consumption of bioactive foods was associated with reduced liver, brain, and gut microbiota alterations in obese rats.