RESUMO
Colitis-associated cancer (CAC) is an aggressive subtype of colorectal cancer that can develop in ulcerative colitis patients and is driven by chronic inflammation and oxidative stress. Current chemotherapy for CAC, based on 5-fluorouracil and oxalipltin, is not fully effective and displays severe side effects, prompting the search for alternative therapies. Dimethylfumarate (DMF), an activator of the nuclear factor erythroid 2-related factor 2 (NRF2), is a potent antioxidant and immunomodelatrory drug used in the treatment of multiple sclerosis and showed a strong anti-inflammatory effect on experimental colitis. Here, we investigated the chemotherapeutic effect of DMF on an experimental model of CAC. Male NMRI mice were given two subcutaneous injections of 1,2 Dimethylhydrazine (DMH), followed by three cycles of dextran sulfate sodium (DSS). Low-dose (DMF30) and high-dose of DMF (DMF100) or oxaliplatin (OXA) were administered from the 8th to 12th week of the experiment, and then the colon tissues were analysed histologically and biochemically. DMH/DSS induced dysplastic aberrant crypt foci (ACF), oxidative stress, and severe colonic inflammation, with a predominance of pro-inflammatory M1 macrophages. As OXA, DMF30 reduced ACF multiplicity and crypt dysplasia, but further restored redox status, and reduced colitis severity by shifting macrophages towards the anti-inflammatory M2 phenotype. Surprisingly, DMF100 exacerbated ACF multiplicity, oxidative stress, and colon inflammation, likely through NRF2 and p53 overexpression in colonic inflammatory cells. DMF had a dual effect on CAC. At low dose, DMF is chemotherapeutic and acts as an antioxidant and immunomodulator, whereas at high dose, DMF is pro-oxidant and exacerbates colitis-associated cancer.
Assuntos
Neoplasias Associadas a Colite , Sulfato de Dextrana , Fumarato de Dimetilo , Macrófagos , Estresse Oxidativo , Animais , Fumarato de Dimetilo/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Masculino , Camundongos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Neoplasias Associadas a Colite/patologia , Neoplasias Associadas a Colite/tratamento farmacológico , Neoplasias Associadas a Colite/prevenção & controle , Sulfato de Dextrana/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Antioxidantes/farmacologia , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Modelos Animais de Doenças , Anti-Inflamatórios/farmacologia , Focos de Criptas Aberrantes/patologia , Relação Dose-Resposta a Droga , Antineoplásicos/farmacologia , Antineoplásicos/toxicidadeRESUMO
Renal amyloid-associated (AA) amyloidosis is a harmful complication of familial Mediterranean fever (FMF). Its occurrence involves polymorphisms and mutations in the Serum Amyloid A1 (SAA1) and Mediterranean Fever (MEFV) genes, respectively. In Algeria, the association between SAA1 variants and FMF-related amyloidosis was not investigated, hence the aim of this case-control study. It included 60 healthy controls and 60 unrelated FMF patients (39 with amyloidosis, and 21 without amyloidosis). All were genotyped for the SAA1 alleles (SAA1.1, SAA1.5, and SAA1.3), and a subset of them for the - 13 C/T polymorphism by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Comparisons between genotype and allele frequencies were performed using Chi-square and Fisher tests. The SAA1.1/1.1 genotype was predominant in amyloid FMF patients, compared to non-amyloid FMF patients (p = 0.001) and controls (p < 0.0001). SAA1.1/1.5 was higher in non-amyloid patients (p = 0.0069) and in controls (p = 0.0082) than in patients with amyloidosis. Bivariate logistic regression revealed an increased risk of AA amyloidosis with three genotypes, SAA1.1/1.1 [odds ratio 7.589 (OR); 95% confidence interval (CI): 2.130-27.041] (p = 0.0018), SAA1.1/1.3 [OR 5.700; 95% CI: 1.435-22.644] (p = 0.0134), and M694I/M694I [OR 4.6; 95% CI: 1.400-15.117] (p = 0.0119). The SAA1.1/1.5 genotype [OR 0.152; 95% CI: 0.040-0.587] (p = 0.0062) was protective against amyloidosis. In all groups, the - 13 C/C genotype predominated, and was not related to renal complication [OR 0.88; 95% CI: 0.07-10.43] (p = 0.915). In conclusion, in contrast to the - 13 C/T polymorphism, the SAA1.1/1.1, SAA1.1/1.3 and M694I/M694I genotypes may increase the risk of developing renal AA amyloidosis in the Algerian population.
Assuntos
Amiloidose , Febre Familiar do Mediterrâneo , Humanos , Febre Familiar do Mediterrâneo/complicações , Febre Familiar do Mediterrâneo/genética , Estudos de Casos e Controles , Amiloidose/genética , Fatores de Risco , Pirina , Proteína Amiloide A SéricaRESUMO
1,2-Dimethylhydrazine (DMH) is a plant toxicant that enters the food web through the diet. It is biotransformed into azoxymethane, a colon carcinogen, during the first hepatic passage. In mice, this study assessed the role of glutamate dehydrogenase (GDH), a key glutaminolysis enzyme in DMH-induced colorectal cancer (CRC). Colon samples were taken from mice given 6 or 15 weekly doses of 20 mg/kg DMH and serially sacrificed. Repeated DMH doses induced early aberrant crypt foci that evolved into irreversible adenocarcinomas over 24 weeks, along with an increase in GDH and lactate dehydrogenase activities (+ 122%, + 238%, P < 0.001), indicating a switch to aerobic glycolysis and glutaminolysis. Transcriptional downregulation of the endogenous GDH inhibitor, sirtuin4, and two redox regulators, mitochondrial sestrin2 and nuclear factor (erythroid derivative 2)-like 2 (- 26% and - 22%, P < 0, 05; and - 30%, P < 0.01), exacerbated mitochondrial stress by boosting mitochondrial superoxide dismutase activity (+ 240% (P < 0.001) while depressing catalase activity and GSH levels (- 57% and - 60%, P < 0.001). In vitro, allosteric GDH inhibition by 50 µM epigallocatechin gallate decreased human carcinoma (HCT-116) cells' viability, clonogenicity, and migration (- 43% and - 57%, P < 0.001, 41%, P < 0.05), while stimulating ROS release (+ 57%, P < 0.001). Dimethylfumarate (DMF), a linear electrophile and mitochondrial fumarate analog, rebalanced ROS levels (- 34%, P < 0.05) and improved GDH activity, cell viability, and tumorogenic capacity (+ 20%, 20%, P < 0.001; and 33%, P < 0.05). Thus, the pathological remodeling of colon mucosa is supported by metabolic reprogramming bypassing uncoupled mitochondria. DMF highlights the critical role of electrophile response elements in modulating redox mithormesis and redox homeostasis during CRC.
Assuntos
Neoplasias do Colo , Ratos , Humanos , Camundongos , Animais , 1,2-Dimetilidrazina/efeitos adversos , 1,2-Dimetilidrazina/metabolismo , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Colo/metabolismo , MucosaRESUMO
Melatonin improved the outcome of septic cardiomyopathy by inhibiting NLRP3 priming induced by reactive oxygen species. To get insights into these events, we studied the melatonin/Nrf2 antioxidant pathways during sepsis in the heart of NLRP3-deficient mice. Sepsis was induced by cecal ligation and puncture and melatonin was given at a dose of 30 mg/kg. Nuclear turnover of Nrf2 and p-Ser40 Nrf2 and expression of ho-1 were enhanced in nlrp3+/+ and nlrp3-/- mice during sepsis. Sepsis caused higher mitochondria impairment, apoptotic and autophagic events in nlrp3+/+ mice than in nlrp3-/- animals. These findings were accompanied by greater levels of Parkin and PINK-1, and lower Mfn2/Drp-1 ratio in nlrp3+/+ than in nlrp3-/- mice during sepsis, supporting less mitophagy in the latter. Ultrastructural analysis of myocardial tissue further confirmed these observations. The activation of NLRP3 inflammasome accounted for most of the deleterious effects of sepsis, whereas the Nrf2-dependent antioxidative response activation in response to sepsis was unable to neutralize these events. In turn, melatonin further enhanced the Nrf2 response in both mice strains and reduced the NLRP3 inflammasome activation in nlrp3+/+ mice, restoring myocardial homeostasis. The data support that the anti-inflammatory efficacy of melatonin against sepsis depends, at least in part, on Nrf2 activation.
Assuntos
Cardiotônicos/uso terapêutico , Traumatismos Cardíacos/tratamento farmacológico , Inflamassomos/antagonistas & inibidores , Melatonina/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Sepse/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Cardiotônicos/farmacologia , Respiração Celular/efeitos dos fármacos , Feminino , Traumatismos Cardíacos/etiologia , Traumatismos Cardíacos/genética , Traumatismos Cardíacos/metabolismo , Inflamassomos/genética , Melatonina/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Fator 2 Relacionado a NF-E2/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Oxirredutases/metabolismo , Sepse/complicações , Sepse/genética , Sepse/metabolismo , Proteína Supressora de Tumor p53/genéticaRESUMO
Familial Mediterranean fever (FMF) is a recessive autoinflammatory disease, mainly occurring in the eastern Mediterranean. In these populations, the five FMF founder mutations are differently distributed. In Algeria, the FMF-causing variants remain poorly explored. This retrospective study aims to report the mutational profile of Algerian FMF patients and to compare it with North African FMF patients. One hundred eighty-three unrelated patients clinically suspected of FMF were recruited from various Algerian hospitals (2007-2015) and tested for mutations in exon 10 of MEFV gene. Molecular analysis identified 144 mutant alleles among 87 of 183 patients (47.5%). p.M694I was the most prevalent pathogenic allele, accounting for 63.2% of mutant alleles, followed by p.M694V and p.M680I occurring with a same frequency (14.5%). Others, p.A744S (6.2%) and p.I692del (1.3%), are less frequent. Interestingly, p.M694I was the most recurrent in patients with renal AA-amyloidosis. Our results provide the first genetic data on FMF in Algeria, demonstrating the predominance of p.M694I and the absence of p.V726A, compared to other North African countries (Morocco, Tunisia, and Egypt). In conclusion, North African FMF patients display differential mutational profiles that may result from the difference in ethnic origin and the genetic heterogeneity among these populations.
Assuntos
Febre Familiar do Mediterrâneo/epidemiologia , Febre Familiar do Mediterrâneo/genética , Mutação , Pirina/genética , África do Norte/epidemiologia , Febre Familiar do Mediterrâneo/classificação , Genótipo , HumanosRESUMO
BACKGROUND: The role of mitochondrial dysfunction in the pathogenesis of inflammatory bowel diseases (IBD) is still being investigated. This study evaluated the therapeutic effect of curcumin (Cur), a polyphenolic electrophile in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced chronic colitis and mitochondrial dysfunction, in mice. METHODS: Colitis was induced by rectal instillation to mice of 30 mg kg-1 TNBS, alone or followed by daily intraperitoneal injections of Cur 25 mg kg-1. Animals were euthanized at days 3, 7, and 14, post TNBS challenge. Colon mitochondria of control mice were treated with 5 µM Cur, and TNBS (50, 100 µM)-toxicity was evaluated by measuring swelling, respiration, and aconitase and fumarase activities. Redox status was evaluated in colon mucosa and in mitochondria. RESULTS: In vitro, a short-term Cur treatment controlled the dose and time dependent mitochondrial toxicity induced by TNBS, by collapsing the generation of superoxide anion and hydroperoxy lipids, rebalancing nitric oxide synthase and aconitase activities, and recoupling mitochondria. In vivo, a daily low-dose Cur abolished mice mortality which reached 27% in model group. Cur improved in a time dependent manner mucosal redox homeostasis, cell apoptosis, mucin depleted crypts and crypt abscesses by controlling prooxidant activity of myeloperoxidase and NO synthase associated to phagocytes influx, quenching hydroperoxy lipids, and reboosting GSH levels. CONCLUSION: Cur, by quenching intra and extra mitochondrial ROS generation, rebalancing aconitase/fumarase and MDA/GSH ratios, and recoupling mitochondria, may support mithormesis priming and remitting in IBD.
Assuntos
Aconitato Hidratase/metabolismo , Curcumina/farmacologia , Peróxidos Lipídicos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mucinas/metabolismo , Óxido Nítrico Sintase/metabolismo , Superóxidos/metabolismo , Ácido Trinitrobenzenossulfônico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Colite/tratamento farmacológico , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Oxirredução/efeitos dos fármacos , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
This study investigated the potential of gadolinium chloride (GdCl3), an inhibitor of kupffer cells on the myeloperoxidase (MPO) function, both in vivo on colon inflammation model and in vitro on thioglycollate-elicited peritoneal neutrophils. Colon inflammation was induced in mice (n = 7) by 4% acetic acid (AA) enema. GdCl3 (10 mg/kg) treatment was given 24 h before AA challenge. Clinical changes during the protocol were scored. Colons were segmented into distal and proximal parts for histological and biochemical assessment. Furthermore, myeloperoxidase (MPO) enzymes were extracted and analyzed by western blot. Short-term GdCl3 treatment inhibited dose-dependently superoxide anion (O2·-), alkaline phosphatase (ALP), and MPO release and promoted neutrophil apoptosis. In vivo, low-dose GdCl3 improved colitis scores and inhibited acute phagocyte recruitment and colon damage within the mucosa as revealed by the decrease in MPO, nitric oxide (NO), and malondialdehyde (MDA) levels. At the same time, GdCl3 restored catalase (CAT), superoxide dismutase (SOD) activities, and reduced glutathione (GSH) levels, thus reversing the MDA/GSH ratio in both distal and proximal colons. Compared to proximal, distal colon was more altered and displayed higher pathological manifestations. Lastly, the induction of apoptosis and regulation of the major nitrosative and oxidative functions of neutrophils by GdCl3 suggests its consideration as a beneficial tool in attenuating colon inflammation.
Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Gadolínio/uso terapêutico , Ácido Acético , Animais , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Gadolínio/farmacologia , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Peroxidase/metabolismo , Superóxido Dismutase/metabolismoRESUMO
This study investigates serum redox status and adenosine catabolism markers in relation to tumor and angiogenesis, in patients with gallbladder carcinoma (GBC). The level of adenosine deaminase (ADA) and xanthine oxidase (XO) activities, nitrites (NO2-), glutathione (GSH) and malondialdehyde (MDA) were measured in sera of 40 GBC patients and 40 healthy donors. In parallel, 15 tumors at TNM stage IV were scored for CD34 expression and microvessel density (MVD). The results showed that XO and ADA activities, nitrites and MDA levels enhanced by 1.26 (p < 0.01), 2.69, 2.0, and 3.2-fold (p < 0.001), respectively, while those of GSH decreased by 44.6% (p < 0.001). According to receiver operating characteristic (ROC) curve, the optimal cut-off for XO, ADA, MDA, GSH and nitrites were 5.41U/l, 17.02 U/l, 3.72 µM, 36.91 µM and 21.21 µM, respectively. Spearman correlation revealed that ADA activity correlated to nitrites levels (r = 0.3419, p < 0.05) and XO activity (r = 0.5487, p < 0.001). Multivariate binary logistic regression analysis revealed that MDA (OR = 5.78, p < 0.05), ADA (OR = 1.28, p < 0.001) and XO (OR = 2.81, p < 0.05) correlated positively to GBC. CD34 was up expressed in 73.3% of tumors at intermediate to high levels. Multiple regression analysis showed that ADA affected MVD (r = 0.604, p < 0.01). The results suggest that high MDA/GSH ratio is a potential biomarker of GBC. In addition, the oxidative adenosine catabolism indicated that active purine salvage pathway could support tumor progression by sustaining angiogenesis.
RESUMO
Arsenic poisoning is a worldwide problem. Thus, we studied the effects of arsenic trioxide (ATO) administration on a 1,2-dimethylhydrazine (DMH)-induced preneoplasic colon carcinogenesis model. Mice were separated into four study groups; the control group received only vehicles. The ATO group received daily a 2.5 mg kg-1 dose for 4 weeks. The DMH group received DMH (20 mg kg-1) twice in two weeks. The third group (D-ATO) had the same as the DMH group with ATO administration starting at week 10. At the end of 14 weeks, colons from sacrificed mice were taken, segmented into distal and proximal and subjected to aberrant crypt foci (ACF), aberrant crypt (AC) counting, alcian blue, H&E and Hoechst histological study and lastly oxidative stress marker analysis as well as mitochondrial swelling assessment. Data showed a significant increase in ACF and AC after DMH treatment, which was further increased after ATO addition. A perturbed histological structure was observed and loss of mucin producing cells in the colon tissue was observed. An important impact on the distal colon compared to the proximal one was noticed. The oxidative stress balance showed a similar pattern with an increase in MPO, NO/l-ornithine balance and MDA, while a decrease was observed in the antioxidant enzymes (CAT, SOD and GSH). In all parameters analyzed, the distal colons showed higher values than proximal. Furthermore, histological cell death analysis in combination with mitochondrial permeability pore opening suggested ATO contribution in the pathological effect. Our study has shown that ATO administration accelerated colon cancer development suggesting the heaviness of such treatments and the need to explore combinations and cycle type formulas.
RESUMO
Colon cancer is thought to develop in a stepwise fashion. In this study, the relationship between aberrant crypt foci (ACF) regional distribution and oxidative stress evolution was studied in a murine model of initial colon carcinogenesis induced by dimethylhydrazine (DMH). Mice were given 2 weekly subcutaneous injections of DMH (20 mg/kg) and killed at the 10th, 12th or 14th week. ACF was scored for number, distribution and crypt multiplicity after methylene-blue coloration and histologically analyzed afterwards. Oxidative stress evaluation was assessed through myeloperoxidase activity (MPO), nitric oxide (NO), L-ornithine and malondialdehyde (MDA) levels as well as antioxidant CAT, SOD and GSH. DMH treatment showed a shift from small to large ACF but also from distal to proximal colon between week 10 and 14 (p < 0.05). This was further illustrated histologically with crypt disruption and mucin depletion. Oxidative stress imbalance was observed in all DMH-treated groups. All markers (MPO, MDA and NO) peaked at week 12 (p < 0.01) and decreased at week 14 (p < 0.05) while L-ornithine decreased through all protocol (p < 0.01). Antioxidants decreased in all points (p < 0.05) but only GSH increased at week 14 (p < 0.05). This work provided insight to response-patterns of oxidative stress between distal and proximal colon, showing for the first time a decreasing implication during the development process and suggesting other inflammatory, immunologic or microbiota implication as factors to be considered during chemotherapy approaches.
Assuntos
1,2-Dimetilidrazina/farmacologia , Focos de Criptas Aberrantes/induzido quimicamente , Carcinogênese/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Focos de Criptas Aberrantes/metabolismo , Animais , Antioxidantes/metabolismo , Biomarcadores Tumorais/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Neoplasias do Colo/metabolismo , Modelos Animais de Doenças , Feminino , Malondialdeído/metabolismo , Camundongos , Mucinas/metabolismo , Óxido Nítrico/metabolismo , Ornitina/metabolismo , Peroxidase/metabolismoRESUMO
BACKGROUND: Immunization with killed Leishmania promastigotes without adjuvant was considered as safe, but gave variable rates of protection. Taking advantage of the immuno-modulatory effect of caffeic acid (CA), a natural polyphenolic antioxidant, we investigated its potentiating effect in autoclaved Leishmania major (ALM)-induced protection of Leishmania major-infected BALB/c. METHODS: First, BALB/c mice were sensitized for 6 weeks either with CA, or ALM alone or combined with caffeic acid (ALM-CA) or Freund's adjuvant (ALM-FA), and subsequently infected with L. major promastigotes. Second, to test the curative effect, CA was given daily for 5 weeks to susceptible mice, starting on week 4 post-infection. Sera, footpads and lymph nodes (LNs) were collected at week 9 post-infection and submitted to biochemical or histological analyses. RESULTS: Compared to the respective controls, our results showed that CA directly healed footpad lesions and reduced the hallmarks of cutaneous leishmaniasis including oxidative inflammation, parasite load, and phagocytes influx and infestation. In sensitized mice, the protection enhanced gradually from ALM-FA, CA, ALM to ALM-CA in parallel to decreased seric IgGt levels. In contrast to ALM-FA, the combined effect of ALM and CA increased specific isotype IgG2, and decreased IL-17 and MCP-1, and phagocyte influx, as attested by the concomitant reduction in myeloperoxidase (MPO) and α-naphthyl acetate esterase (ANAE) activities. ALM-CA shifted IFN-γ/TGF-ß and iNO synthase/arginase1 (iNOS/Arg1) balances in a Th1 immune response that control efficiently cutaneous lesions and LNs hypertrophy, and reactivate the death of infected phagocytes. CONCLUSIONS: Therefore, CA combined with ALM synergizes with L. major antigens for priming innate cells, through early polarization to optimal Th1 response that leads to IFN-γ and iNOS-dependent leishmanicidal activity of neutrophils and macrophages.
Assuntos
Arginase/metabolismo , Ácidos Cafeicos/farmacologia , Imunoglobulina G/metabolismo , Interferon gama/metabolismo , Leishmania major/imunologia , Óxido Nítrico Sintase/metabolismo , Fagócitos/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Animais , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/metabolismo , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Familial Mediterranean fever (FMF, OMIM 249100) is the most common hereditary fever, resulting from mutations in MEFV. FMF is characterized by episodic febrile attacks and polyserositis. Renal AA-amyloidosis is a major complication, which often leads to end-stage renal disease in untreated patients. The data about the renal AA-amyloidosis secondary to FMF are scarce in North African countries and non-existent in Algeria. We aimed to investigate the MEFV mutations associated with this complication in an Algerian patient cohort. Molecular analysis included 28 unrelated Algerian FMF patients with ascertained amyloidosis, 23 of them were symptomatic and 5 were asymptomatic. For this study, a group of 20 FMF patients without renal amyloidosis were selected as controls according to their age, disease onset and disease duration. The mutations were detected by sequencing exon 10 of MEFV. A total of 87.5% (49/56) mutant alleles were identified in 27/28 analyzed patients; p.M694I was predominant and appeared with an allele frequency of 62.5%, followed by p.M694V (17.85%), p.M680I (5.35%) and p.I692Del (1.78%). Remarkably, only p.M694I mutation was observed among the asymptomatic patients. The M694I/M694I genotype, identified in 14/27 (52%) patients, was significantly associated with the development of amyloidosis compared to group of controls (p = 0.022). This study did not link the M694V/M694V genotype to the renal complication despite the fact that it has been observed only in the patients with amyloidosis (3/27; 11%) (p = 0.349). The association of other identified genotypes to this complication was statistically insignificant. The progression of amyloidosis led to end-stage renal disease in 14 patients with 6 deaths. This study shows that p.M694I homozygosity is a potential genetic risk factor for the development of renal AA-amyloidosis in Algerian FMF patients.
Assuntos
Amiloidose/genética , Febre Familiar do Mediterrâneo/genética , Frequência do Gene/genética , Pirina/genética , Adolescente , Adulto , Argélia , Amiloidose/patologia , Sequência de Bases , Criança , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Falência Renal Crônica/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sequência de DNA , Adulto JovemRESUMO
We have previously shown that ethanolic extract from bark (EEB) of Salix aegyptiaca (Musk Willow) can inhibit proliferation and motility and induce apoptosis in colon cancer cells. Tandem mass spectrometry revealed EEB to be rich in catechin, catechol, and salicin. The present study investigated the chemopreventive effect of HPLC-fingerprinted EEB on 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) formation in mice. DMH (20 mg/kg body weight) was weekly injected subcutaneously to mice for the first 2 weeks. EEB (100 and 400 mg/kg body weight) was provided orally from the 7th to 14th week, after which colon tissues were evaluated histologically and biochemically. DMH treatment induced high number of ACF; EEB significantly reduced the number and multiplicity of ACF, along with a restoration in goblet cells and mucin accumulation. EEB supplementation improved the markers of inflammation (myeloperoxidase and neutrophil infiltration) and oxidative stress. More importantly, EEB amplified apoptosis of neoplastic cells in the colon mucosa of DMH-treated mice. It also lowered levels of markers for early transformation events such as EGFR, nuclear ß-catenin, and COX-2 in colon cancer cell lines HT-29 and HCT-116. The innocuity of EEB (up to 1600 mg/kg) to mice reinforces its potential as a chemopreventive agent.
Assuntos
1,2-Dimetilidrazina/toxicidade , Focos de Criptas Aberrantes/tratamento farmacológico , Anticarcinógenos/farmacologia , Neoplasias do Colo/prevenção & controle , Extratos Vegetais/farmacologia , Salix/química , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/patologia , Animais , Anticarcinógenos/química , Carcinógenos/toxicidade , Cromatografia Líquida de Alta Pressão , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Etanol/química , Células HCT116/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/químicaRESUMO
Abstract ß-Thalassemia (ß-thal) is a genetic disorder, representing a major health problem in Algeria. It is associated with altered lipid levels and a state of oxidative stress that can lead to cardiac complications and premature death. We examined the plasma lipid profile and redox status of 46 patients with ß-thal major (ß-TM) and ß-thal intermedia (ß-TI) compared to 36 healthy subjects. Plasma lipids including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were investigated. Oxidative status was evaluated by measuring malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT) activity. The potential relationships between these parameters and the hemoglobin (Hb) blood concentrations, serum ferritin, duration and frequency of transfusion, splenectomy as well as age, were examined. Our data indicated that the study patients were under increased state of oxidative stress associated with hypertriglyceridemia, and hypocholesterolemia. The CAT activity was negatively correlated with Hb concentration and LDL-C/TG ratio and positively with years of transfusion. The elevated TC/HDL-C ratio particularly in ß-TM patients who were younger, correlated positively with ferritinemia and triglyceride levels and suggested an increased coronary risk. This heightened risk state should lead to the inclusion of this index (TC/HDL-C) in clinical management, particularly in splenectomized patients.
Assuntos
Metabolismo dos Lipídeos , Lipídeos/sangue , Estresse Oxidativo , Talassemia beta/sangue , Talassemia beta/metabolismo , Adolescente , Adulto , Catalase/sangue , Catalase/metabolismo , Feminino , Glutationa/sangue , Glutationa/metabolismo , Humanos , Masculino , Malondialdeído/sangue , Malondialdeído/metabolismo , Oxirredução , Adulto Jovem , Talassemia beta/complicaçõesRESUMO
Reactive oxygen species- (ROS-) mediated injury has been implicated in several inflammatory disorders, including inflammatory bowel disease (IBD). NADPH oxidases (NOXs) are the major source of endogenous ROS. Here, we investigated the role of NOXs derived-ROS in a mouse model of colitis induced by the proinflammatory cytokine, tumor necrosis factor-α (TNF-α). Intraperitoneal injection of TNFα (10 µg · kg(-1)) induced an acute inflammation of the colon and a marked increase in expression of NADPH oxidase 1 (NOX1), a colon specific NADPH oxidase isoform. TNFα-induced colitis was also characterized by high production of keratinocyte-derived chemokine (KC) and mucosal infiltration of neutrophils, NOX2-expressing cells. Concomitantly, ROS production and lipid peroxidation were significantly enhanced while catalase activity and glutathione level were reduced indicating a redox imbalance in the colon. Furthermore, the redox-sensitive MAP kinases, ERK1/2 and p38 MAPK, were activated during TNFα-induced colitis. Pretreatment of mice with apocynin, an NADPH oxidase inhibitor with antioxidant properties, before TNFα challenge, prevented all these events. These data suggest that ROS derived from NADPH oxidases (mainly NOX1 and NOX2) and MAP kinase pathways could contribute to the induction and expansion of oxidative lesions characteristics of IBD and that apocynin could potentially be beneficial in IBD treatment.
Assuntos
Acetofenonas/farmacologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Western Blotting , Masculino , Camundongos , NADH NADPH Oxirredutases/metabolismo , NADPH Oxidase 1 , NADPH Oxidases/metabolismo , Infiltração de Neutrófilos/fisiologia , Neutrófilos/metabolismo , Estresse Oxidativo/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
UNLABELLED: Cirrhosis is commonly accompanied by impaired defense functions of polymorphonuclear leucocytes (PMNs), increased patient susceptibility to infections, and hepatocellular carcinoma (HCC). PMN antimicrobial activity is dependent on a massive production of reactive oxygen species (ROS) by nicotinamide adenine dinucleotide phosphate (NADPH) 2 (NADPH oxidase 2; NOX2), termed respiratory burst (RB). Rapamycin, an antagonist of mammalian target of rapamycin (mTOR), may be used in the treatment of HCC and in transplanted patients. However, the effect of mTOR inhibition on the PMN RB of patients with cirrhosis remains unexplored and was studied here using the bacterial peptide, formyl-Met-Leu-Phe (fMLP), as an RB inducer. fMLP-induced RB of PMN from patients with decompensated alcoholic cirrhosis was strongly impaired (30%-35% of control) as a result of intracellular signaling alterations. Blocking mTOR activation (phospho-S2448-mTOR) with rapamycin further aggravated the RB defect. Rapamycin also inhibited the RB of healthy PMNs, which was associated with impaired phosphorylation of the NOX2 component, p47phox (phox: phagocyte oxidase), on its mitogen-activated protein kinase (MAPK) site (S345) as well as a preferential inhibition of p38-MAPK relative to p44/42-MAPK. However, rapamycin did not alter the fMLP-induced membrane association of p47phox and p38-MAPK in patients' PMNs, but did prevent their phosphorylation at the membranes. The mTOR contribution to fMLP-induced RB, phosphorylation of p47phox and p38-MAPK was further confirmed by mTOR knockdown in HL-60 cells. Finally, rapamycin impaired PMN bactericidal activity, but not bacterial uptake. CONCLUSION: mTOR significantly up-regulates the PMN RB of patients with cirrhosis by p38-MAPK activation. Consequently, mTOR inhibition by rapamycin dramatically aggravates their PMN RB defect, which may increase patients' susceptibility to infection. Thus, concerns should be raised about the use of rapamycin in immuno-depressed patients.
Assuntos
Cirrose Hepática Alcoólica/metabolismo , Neutrófilos/metabolismo , Explosão Respiratória/imunologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Antibióticos Antineoplásicos/farmacologia , Citosol/metabolismo , Interações Medicamentosas , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Feminino , Células HL-60 , Humanos , Cirrose Hepática Alcoólica/tratamento farmacológico , Cirrose Hepática Alcoólica/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Pessoa de Meia-Idade , N-Formilmetionina Leucil-Fenilalanina/análogos & derivados , N-Formilmetionina Leucil-Fenilalanina/farmacologia , NADPH Oxidases/metabolismo , Neutrófilos/imunologia , Neutrófilos/microbiologia , Fagocitose/imunologia , Fosforilação/efeitos dos fármacos , Fosforilação/imunologia , Explosão Respiratória/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
This study investigated the effect of short curcumin treatment, a natural antioxidant on 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in mice. The incidence of aberrant crypt foci (ACF) was 100%, with 54 ± 6 per colon, 10 weeks after the first DMH injection and reached 67 ± 12 per colon after 12 weeks. A high level of undifferentiated goblet cells and a weak apoptotic activity were shown in dysplastic ACF. The morphological alterations of colonic mucosa were associated to severe oxidative stress ratio with 43% increase in malondialdehyde vs. 36% decrease in GSH. DMH also increased inducible nitric synthase (iNOS) mRNA transcripts (250%), nitrites level (240%) and arginase activity (296%), leading to nitrosative stress and cell proliferation. Curcumin treatment, starting at week 10 post-DMH injection for 14 days, reduced the number of ACF (40%), iNOS expression (25%) and arginase activity (73%), and improved redox status by approximately 46%, compared to DMH-treated mice. Moreover, curcumin induced apoptosis of dysplastic ACF cells without restoring goblet cells differentiation. Interestingly, curcumin induced a parallel increase in TGF-ß1 and HES-1 transcripts (42% and 26%, respectively). In conclusion, the protective effect of curcumin was driven by the reduction of arginase activity and nitrosative stress. The up regulation of TGF-ß1 and HES-1 expression by curcumin suggests for the first time, a potential interplay between these signalling pathways in the chemoprotective mechanism of curcumin.
Assuntos
1,2-Dimetilidrazina/toxicidade , Focos de Criptas Aberrantes/tratamento farmacológico , Arginase/metabolismo , Neoplasias do Colo/metabolismo , Curcumina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Focos de Criptas Aberrantes/induzido quimicamente , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Arginase/antagonistas & inibidores , Arginase/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Masculino , Camundongos , Transdução de Sinais , Fatores de Transcrição HES-1 , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Regulação para CimaRESUMO
The effect of N-acetylcysteine (NAC), a pharmacological antioxidant was investigated in a murine model of chronic colitis. Male NMRI mice were given 5% dextran sulfate sodium (DSS) in drinking water for 5 days followed by 10 days of water, three times. Compared to control mice given water, DSS-treated mice displayed severe imbalanced redox status with decreased glutathione and catalase, but increased malondialdehyde, protein carbonyls, nitric oxide and myeloperoxidase levels, at days 35th (active colitis) and 45th (recovery period). It also resulted in mitochondrial dysfunction, mucosal ulcers, mucin-depleted crypts and epithelial cell apoptosis. Crypt abscesses and glandular hyperplasia occurred selectively in distal colon. NAC (150 mg/kg) given in drinking water for 45 days along with 3 DSS cycles improved the hallmarks of DSS-colitis. Interestingly, the moderate impact of NAC on lipids and proteins oxidation correlated with myeloperoxidase and nitric oxide levels.NAC as a mucoregulator and a thiol restoring agent is protective on oxidative crypt alterations, mucin depletion, epithelial cell hyperplasia and apoptosis. Taken together, our results highlight the role of NAC as a scavenger of phagocytes-derived reactive oxygen species in mice DDS-colitis, suggesting that a long term NAC diet might be beneficial in inflammatory bowel diseases and colorectal cancer.
Assuntos
Acetilcisteína/farmacologia , Colite/tratamento farmacológico , Sulfato de Dextrana/farmacologia , Células Epiteliais/patologia , Mucosa Intestinal/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mucinas/deficiência , Acetilcisteína/uso terapêutico , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Células Epiteliais/efeitos dos fármacos , Hiperplasia/tratamento farmacológico , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacosRESUMO
The up regulation of gut mucosal cytokines such as tumor necrosis factor (TNF)-α and oxidative stress have been related to inflammatory bowel diseases (IBD) such as ulcerative colitis (UC) and Crohn's disease (CD). This study investigated an immune-mediated model of colitis. TNF-α injected intraperitonally to mice induced a dose-dependent recruitment of neutrophils into abdominal mesentery. The leukocytes influx induced by TNF-α (10 µg kg(-1) body weight) increased by 3 fold liver and colon damage scores. TNF-α-colitis was characterized by hemorrhagic edemas and crypt abscesses massively infiltrated by inflammatory cells, namely neutrophils. Moreover, TNF-α-toxicity resulted in liver steatosis and foci of necrosis infiltrated by Kupffer cells and neutrophils in parenchyma and around the centrilobular veins. The involvement of oxidative stress was evaluated using aminoguanidine (AG) as selective inhibitor of inducible NO synthase (iNOS) and curcumin (Cur), the polyphenolic antioxidant of turmeric (Curcuma longa L.). TNF-α-toxicity led to significant increase in myeloperoxidase (MPO, an index of neutrophils infiltration), nitrites (stable nitric oxide metabolites) and malondialdehyde (MDA, a marker of lipid peroxides) levels and cell apoptosis in liver and colon. AG and Cur treatments significantly attenuated the hallmarks of oxidative stress, neutrophils influx and ROS-related cellular and histological damages, in TNF-α-treated mice. Taken together, our results provide insights into the role of phagocytes-derived oxidants in TNF-α-colitis in mice. Cur and AG, by inhibiting neutrophils priming and iNOsynthase could be effective against oxidative bowel damages induced in IBD by imbalanced gut immune response.
Assuntos
Antioxidantes/uso terapêutico , Colite/tratamento farmacológico , Curcumina/uso terapêutico , Guanidinas/uso terapêutico , Fígado/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Apoptose , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Curcumina/farmacologia , Guanidinas/farmacologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Neutrófilos/imunologia , Óxido Nítrico/imunologia , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/imunologia , Fator de Necrose Tumoral alfaRESUMO
Phospholipase D (PLD), a major source of lipid second messengers (phosphatidic acid, diglycerides) in many cell types, is tightly regulated by protein kinases, but only a few of them have been identified. We show here that protein kinase B (AKT) is a novel major signaling effector of PLD activity induced by the formylpeptide f-Met-Leu-Phe (fMLP) in human neutrophil-like HL-60 cells (dHL-60 cells). AKT inhibition with the selective antagonist AKTib1/2 almost completely prevented fMLP-mediated activity of PLD, its upstream effector ERK1/2, but not p38 MAPK. Immunoprecipitation studies show that phosphorylated AKT, ERK, and PLD2 form a complex induced by fMLP, which can be prevented by AKTib1/2. In cell-free systems, AKT1 stimulated PLD activity via activation of ERK. AKT1 actually phosphorylated ERK2 as a substrate (K(m) 1 µm). Blocking AKT activation with AKTib1/2 also prevented fMLP- but not phorbol 12-myristate 13-acetate-mediated NADPH oxidase activation (respiratory burst, RB) of dHL-60 cells. Impaired RB was associated with defective membrane translocation of NADPH oxidase components p67(phox) and p47(phox), ERK, AKT1, AKT2, but not AKT3. Depletion of AKT1 or AKT2 with antisense oligonucleotides further indicates a partial contribution of both isoforms in fMLP-induced activation of ERK, PLD, and RB, with a predominant role of AKT1. Thus, formylpeptides induce sequential activation of AKT, ERK1/2, and PLD, which represents a novel signaling pathway. A major primarily role of this AKT signaling pathway also emerges in membrane recruitment of NOX2 components p47(phox), p67(phox), and ERK, which may contribute to assembly and activation of the RB motor system, NADPH oxidase.