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1.
Antioxidants (Basel) ; 13(9)2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39334771

RESUMO

This research identified the bioactive compounds and antioxidant capacity of the extractable (EP) and non-extractable (NEP) polyphenol fractions of berrycactus (BC). Additionally, the effects of BC and its residue (BCR) on preventing AOM/DSS-induced early colon carcinogenesis were evaluated in vivo. Male Sprague Dawley rats were randomly assigned to six groups (n = 12/group): healthy control (C), AOM/DSS, BC, BCR, BC+AOM/DSS, and BCR+AOM/DSS. NEP was obtained through acid hydrolysis using H2SO4 and HCl (1 M or 4 M). The HCl-NEP fraction exhibited the highest total phenolic and flavonoid content, while condensed tannins were more abundant in the H2SO4-NEP fraction. A total of 33 polyphenols were identified by UPLC-QTOF-MSE in both EP and NEP, some of which were novel to BC. Both NEP hydrolysates demonstrated significant total antioxidant capacity (TEAC), with HCl-NEP exhibiting the highest ORAC values. The BC+AOM/DSS and BCR+AOM/DSS groups exhibited fewer aberrant crypt foci (p < 0.05), reduced colonic epithelial injury, and presented lower fecal ß-glucuronidase activity, when compared to AOM/DSS group. No differences in butyric acid concentrations were observed between groups. This study presents novel bioactive compounds in EP and NEP from BC that contribute to chemopreventive effects in early colon carcinogenesis, while reducing fecal ß-glucuronidase activity and preserving colonic mucosal integrity.

2.
J Mol Histol ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39122895

RESUMO

Corosolic acid (CA) is a well-known natural pentacyclic triterpene found in numerous therapeutic plants that can exhibit many bioactivities including anti-inflammatory and anti-tumor actions. The current investigation explores the chemoprotective roles of CA against azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) in rats. Thirty Sprague Dawley rats were grouped in 5 cages; Group A, normal control rats inoculated subcutaneously (sc) with two doses of normal saline and fed orally on 10% tween 20; Groups B-E received two doses (sc) of azoxymethane in two weeks and treated with either 10% tween 20 (group B) or two intraperitoneal injections of 35 mg/kg 5-fluorouracil each week for one month (group C), while group D and E treated with 30 and 60 mg/kg, respectively, for 2 months. The toxicity results showed lack of any behavioral abnormalities or mortality in rats ingested with up-to 500 mg/kg of CA. The present AOM induction caused a significant initiation of ACF characterized by an increased number, larger in size, and well-matured tissue clusters in cancer controls. AOM inoculation created a bizarrely elongated nucleus, and strained cells, and significantly lowered the submucosal glands in colon tissues of cancer controls compared to 5-FU or CA-treated rats. CA treatment led to significant suppression of ACF incidence, which could be mediated by its modulatory effects on the immunohistochemical proteins (pro-apoptotic (Bax) and reduced PCNA protein expressions in colon tissues). Moreover, CA-treated rats had improved oxidative stress-mediated cytotoxicity indicated by increased endogenous antioxidants (SOD and CAT) and reduced lipid peroxidation indicators (MDA). In addition, CA ingestion (30 and 60 mg/kg) suppressed the inflammatory cascades, indicated by decreased serum TNF-α and IL-6 cytokines and increased anti-inflammatory (IL-10) cytokines consequently preventing further tumor development. CA treatment maintained liver and kidney functions in rats exposed to AOM cytotoxicity. CA could be a viable alternative for the treatment of oxidative-related human disorders including ACF.

3.
Asian Pac J Cancer Prev ; 25(6): 2059-2067, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38918668

RESUMO

OBJECTIVE: This study examined the morphological changes in the colonic mucosa and the presence of inflammation in rats induced with 1,2-dimethylhydrazine (DMH) 30 mg/kg BW over 9, 11, and 13 weeks without a latency period. METHODS: Hematoxylin and eosin staining was performed to assess the morphology and characteristic alteration of the epitheliocytes in the colon. Immunohistochemistry was employed to assess the expression of tumor necrosis factor (TNF)-α and cyclooxygenase-2 (COX-2). The difference in the severity of inflammation and COX-2 expression was examined using one-way analysis of variance. The correlation of COX-2 expression with the severity of inflammation was analyzed using Spearman's rank correlation test. RESULT: Until week 13, chronic inflammation and non-hyperplastic and hyperplastic aberrant crypt foci occurred. The severity of inflammation gradually shifted from high moderate to low moderate. TNF-α expression was high in all groups; however, COX-2 expression was gradually lower with longer duration of induction, which corresponded with the severity of inflammation. CONCLUSION: DMH induction until week 13 without a latency period caused chronic inflammation without the formation of adenoma or adenocarcinoma. A very strong correlation was established between COX-2 expression and inflammation.


Assuntos
1,2-Dimetilidrazina , Neoplasias Colorretais , Ciclo-Oxigenase 2 , Inflamação , Fator de Necrose Tumoral alfa , Animais , 1,2-Dimetilidrazina/toxicidade , Ratos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inflamação/induzido quimicamente , Inflamação/patologia , Inflamação/metabolismo , Masculino , Fator de Necrose Tumoral alfa/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Carcinógenos/toxicidade , Ratos Sprague-Dawley , Focos de Criptas Aberrantes/patologia , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/metabolismo , Colo/patologia , Colo/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/metabolismo
4.
Asian Pac J Cancer Prev ; 25(2): 563-573, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415543

RESUMO

OBJECTIVE: The study's aim was to evaluate Brazilian Brown Propolis (BBP) and Artepillin C (ARC) chemopreventive action in Wistar rats' colons. METHODS: Fifty male Wistar rats were divided into ten experimental groups, including control groups, groups with and without 1,2-dimethylhydrazine (DMH) induction, and BBP, ARC, and ARC enriched fraction (EFR) treatments, for sixteen weeks. Aberrant crypt foci (ACF) were classified as hyperplastic or dysplastic, and proliferating cell nuclear antigen (PCNA) expression was quantified. RESULT: ACF amounts in experimental groups (induced or not) decreased in both colon portions, while the isolated Aberrant Crypt (AC) number increased. Experimental groups of animals showed higher hyperplasia and dysplasia amounts compared with control groups. The ACF dysplastic amount present in groups induced and treated, in both colon portions, had similar values to IDMH (DMH induction group without treatment). In addition, DMH was effective in ACF inducing and there was positive staining for PCNA in basal and upper dysplastic foci portions in all experimental groups, in the mitotic index (MI) evaluation. To conclude, considering all the experimental groups, the one treated with EFR (fraction enriched with ARC) had the lowest rates of cell proliferation. CONCLUSION: BBP and its derivatives prevented crypt cell clonal expansion.


Assuntos
Focos de Criptas Aberrantes , Antineoplásicos , Neoplasias do Colo , Fenilpropionatos , Própole , Ratos , Animais , Masculino , Ratos Wistar , Neoplasias do Colo/tratamento farmacológico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Própole/farmacologia , Própole/uso terapêutico , 1,2-Dimetilidrazina/toxicidade , Brasil , Focos de Criptas Aberrantes/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinógenos
5.
Braz. j. med. biol. res ; 57: e13306, fev.2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564161

RESUMO

Arbutin is utilized in traditional remedies to cure numerous syndromes because of its anti-microbial, antioxidant, and anti-inflammatory properties. This study aimed to evaluate chemopreventive effects of arbutin on azoxymethane (AOM)-induced colon aberrant crypt foci (ACF) in rats. Five groups of rats were used: normal control group (rats injected hypodermically with sterile phosphate-buffered saline once per week for two weeks) and groups 2-5, which were subcutaneously inoculated with 15 mg/kg AOM once a week for two weeks. AOM control and 5-fluorouracil (5-FU) control groups were fed 10% Tween orally daily for 8 weeks using a feeding tube. The treated groups were fed 30 and 60 mg/kg arbutin every day for 2 months. ACF from the AOM control group had aberrant nuclei in addition to multilayered cells and an absence of goblet cells. The negative control group displayed spherical cells and nuclei in basal positions. Histological examination revealed a reduced number of AFC cells from colon tissues of the 5-FU reference group. Arbutin-fed animals showed down-regulation of proliferating cell nuclear antigen (PCNA) and up-regulation of Bax protein compared to AOM control. Rats fed with arbutin displayed a significant increase of superoxide dismutase (SOD) and catalase (CAT) activities in colon tissue homogenates compared to the AOM control group. In conclusion, arbutin showed therapeutic effects against colorectal cancer, explained by its ability to significantly decrease ACF, down-regulate PCNA protein, and up-regulate Bax protein. In addition, arbutin significantly increased SOD and CAT, and decreased malondialdehyde (MDA) levels, which might be due to its anti-proliferative and antioxidant properties.

6.
Carbohydr Polym ; 331: 121878, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388061

RESUMO

Pectins are a class of soluble polysaccharides that can have anticancer properties through several mechanisms. This study aimed to characterize the molecular structure of water-soluble fractions (WSF) derived from ripe and unripe papayas and assess their biological effects in two models: the 3D colon cancer spheroids to measure cell viability and cytotoxicity, and the in vivo model to investigate the inhibition of preneoplastic lesions in rats. WSF yield was slightly higher in ripe papaya, and both samples mainly consisted of pectin. Both pectins inhibited the growth of colon cancer HT29 and HCT116 spheroids. Unripe pectin disturbed HT29/NIH3T3 spheroid formation, decreased HCT116 spheroid viability, and increased spheroid cytotoxicity. Ripe pectin had a more substantial effect on the reduction of spheroid viability for HT29 spheroids. Furthermore, in vivo experiments on a rat model revealed a decrease in aberrant crypt foci (ACF) formation for both pectins and increased apoptosis in colonocytes for ripe papaya pectins. The results suggest potential anticancer properties of papaya pectin, with ripe pectin showing a higher potency.


Assuntos
Carica , Neoplasias do Colo , Ratos , Animais , Camundongos , Pectinas/farmacologia , Pectinas/química , Carica/química , Células NIH 3T3 , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Proliferação de Células , Colo
7.
Food Res Int ; 175: 113666, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129019

RESUMO

Marolo (Annona crassiflora) is an underutilized Brazilian Cerrado fruit with few reports in the literature about its bioactive compounds and functional properties. In this context, the chemoprevention against the carcinogen 1,2-dimethylhydrazine (DMH)-induced pre-neoplastic lesions in Wistar rat colon was investigated and correlated with marolo's antioxidant activity and the contents of phenolic compounds and bioactive amines. Total phenolic compounds (TPC) and total flavonoids compounds (TFC) were determined in the marolo pulp extract by spectrophotometric and Ultra-Performance Liquid Chromatography and diode array detection (UPLC-DAD) analysis. Free bioactive amines were determined by High Performance Liquid Chromatography and fluorescence detection (HPLC-FLD) after post column derivatization with o-phthalaldehyde. In addition, the in vitro antioxidant activity was determined by DPPH, and ABTS. Wistar rats were treated orally with marolo pulp at 0.7, 1.4 and 2.8 g/kg body weight (bw)/day added to a standard ration. Four subcutaneous injections of DMH (40 mg/kg bw) were used to induce a pre-neoplastic lesion that was assessed by the aberrant crypt foci (ACF) assay. The marolo pulp (fresh weigh) showed high content of total phenolic compounds (9.16 mg GAE/g), with predominance of chlorogenic acid (1.86 µg/g) and epicatechin (0.99 µg/g), and total flavonoids (7.26 mg CE/g), ∼85 % of the TPC. The marolo pulp had significant contents of tyramine (31.97 mg/kg), putrescine (20.65 mg/kg), and spermidine (6.32 mg/kg). The marolo pulp inhibited (p < 0.05) pre-neoplastic lesions induced by DMH administration at the all concentrations tested. These findings indicate that marolo pulp has a colon carcinogenesis chemopreventive effect, which could be due to, at least in parts, its antioxidant action associated with its phenolics and flavonoids content as well of spermidine.


Assuntos
Antioxidantes , Fenol , Ratos , Animais , Antioxidantes/farmacologia , Antioxidantes/análise , Ratos Wistar , Espermidina , 1,2-Dimetilidrazina/toxicidade , Carcinogênese , Fenóis/farmacologia , Fenóis/análise , Flavonoides/farmacologia
8.
Curr Nutr Rep ; 12(4): 662-678, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38041707

RESUMO

PURPOSE OF REVIEW: The main purpose of this review, mainly based on preclinical studies, is to summarize the pharmacological and biochemical evidence regarding natural polyphenols against colorectal cancer and highlight areas that require future research. RECENT FINDINGS: Typically, colorectal cancer is a potentially preventable and curable cancer arising from benign precancerous polyps found in the colon's inner lining. Colorectal cancer is the third most common cancer, with a lifetime risk of approximately 4 to 5%. Genetic background and environmental factors play major roles in the pathogenesis of colorectal cancer. Theoretically, a multistep process of colorectal carcinogenesis provides enough time for anti-tumor pharmacotherapy of colorectal cancer. Chronic colonic inflammation, oxidative stress, and gut microbiota imbalance have been found to increase the risk for colorectal cancer development by creating genotoxic stress within the intestinal environment to generate genetic mutations and epigenetic modifications. Currently, numerous natural polyphenols have shown anti-tumor properties against colorectal cancer in preclinical research, especially in colorectal cancer cell lines. In this review, the current literature regarding the etiology and epidemiology of colorectal cancer is briefly outlined. We highlight the findings of natural polyphenols in colorectal cancer from in vitro and in vivo studies. The scarcity of human trials data undermines the clinical use of natural polyphenols as anti-colorectal cancer agents, which should be undertaken in the future.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Polifenóis/farmacologia , Epigênese Genética
9.
J Pharm Pharmacol ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37874746

RESUMO

ABSTRACT: Based on the effectiveness of resveratrol and curcumin in carcinogenesis, (E)-3-(4-hydroxy-3-methoxyphenyl)-N'-((E)-4-methoxybenzylidene) acrylohydrazide (PQM-162), curcumin-resveratrol hybrid derivative, was designed by molecular hybridization using a hydrazone functionality as a spacer moiety between pharmacophoric fragments inspired by the parent compounds. OBJECTIVES: The present study aimed to evaluate the chemopreventive effects of the hybrid against pre-neoplastic lesions induced in the colon of rodents. METHODS: The doses were determined based on the reduction in DNA damage induced by doxorubicin [15 mg/kg body weight (b.w.)] in peripheral blood of Swiss mice. Doses of 8, 16, 32, and 64 mg/kg b.w. were antimutagenic. For the evaluation of pre-neoplastic lesions in the colon, Wistar rats were treated with PQM-162 at doses of 0.5, 1, and 2 mg/kg b.w. for 6 weeks using three approaches: simultaneous treatment, pre-treatment, and post-treatment. Pre-neoplastic lesions were induced with 1,2 dimethylhydrazine (160 mg/kg b.w.). KEY FINDINGS: PQM-162 reduced the formation of aberrant crypt foci in the simultaneous treatment and post-treatment. TNF-α and COX-2 mRNA levels decreased, while Nrf2 mRNA levels increased. PQM-162 also reduced the expression of COX-2, PCNA, and ß-catenin protein markers and increased Nrf2 expression. CONCLUSION: Our findings suggest a chemopreventive potential of PQM-162 in colorectal carcinogenesis, which acts on anti-inflammatory, antioxidant, and cell proliferation pathways.

10.
Int J Exp Pathol ; 104(6): 304-312, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37594023

RESUMO

Colorectal cancer, which is the third leading cause of cancer-related deaths worldwide, is a multistep disease, featuring preneoplastic aberrant crypt foci (ACF) as the early morphological manifestation. The roles of hemichannel-forming transmembrane Pannexin 1 (Panx1) protein have not been investigated in the context of colon carcinogenesis yet, although it has contrasting roles in other cancer types. Thus, this study was conducted to examine the effects of Panx1 knockout (Panx1-/- ) on the early events of chemically induced colon carcinogenesis in mouse. Wild type (WT) and Panx1-/- female C57BL6J mice were submitted to a chemically induced model of colon carcinogenesis by receiving six intraperitoneal administrations of 1,2-dimethylhydrazine (DMH) carcinogen. Animals were euthanized 8 h (week 7) or 30 weeks (week 37) after the last DMH administration in order to evaluate sub-acute colon toxicity outcomes or the burden of ACF, respectively. At week 7, Panx1 genetic ablation increased DMH-induced genotoxicity in peripheral blood cells, malondialdehyde levels in the colon, and apoptosis (cleaved caspase-3) in colonic crypts. Of note, at week 37, Panx1-/- animals showed an increase in aberrant crypts (AC), ACF mean number, and ACF multiplicity (AC per ACF) by 56%, 57% and 20%, respectively. In essence, our findings indicate that Panx1 genetic ablation promotes preneoplastic ACF development during chemically induced mouse colon carcinogenesis, and a protective role of Panx1 is postulated.


Assuntos
Focos de Criptas Aberrantes , Neoplasias do Colo , Lesões Pré-Cancerosas , Camundongos , Feminino , Animais , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/genética , 1,2-Dimetilidrazina/efeitos adversos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Colo , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/genética , Proteínas do Tecido Nervoso/efeitos adversos , Conexinas/genética , Conexinas/farmacologia
11.
Food Res Int ; 170: 112917, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316039

RESUMO

Blackcurrant press cake (BPC) is a source of anthocyanins, and this study evaluated the bioactivity and gut microbiota modulation of blackcurrant diets with or without 1,2 dimethylhydrazine (DMH)-induced colon carcinogenesis in rats. In colon cancer-induced rats (CRC), BPC at the highest dosages increased pro-inflammatory parameters and the expression of anti-apoptotic cytokines, accentuating colon cancer initiation by aberrant crypts and morphological changes. Fecal microbiome analysis showed that BPC altered the composition and function of the gut microbiome. This evidence suggests that high doses of BPC act as a pro-oxidant, accentuating the inflammatory environment and CRC progression.


Assuntos
Neoplasias do Colo , Microbiota , Animais , Ratos , Antocianinas/farmacologia , Estresse Oxidativo , Inflamação , Veículos Farmacêuticos
12.
Cancers (Basel) ; 15(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37190329

RESUMO

Dietary supplementation with pterostilbene (PS) and/or a probiotic (PRO) may ameliorate the intestinal microbiota in disease conditions. This study aims to evaluate PS and PRO for the chemoprevention of putative precursor lesions for colorectal cancer (CRC) in an experimental model of intestinal carcinogenesis with 1,2-dimethylhydrazine (1,2-DMH). Sixty male Wistar rats were equally divided into five groups: Sham, 1,2-DMH, 1,2-DMH + PS, 1,2-DMH + PRO, and 1,2-DMH + PS + PRO. PRO (5 × 107/mL) was offered in water, and PS (300 ppm) was provided in the diet ad libitum. 1,2-DMH (20 mg/kg/week) was administered for 15 consecutive weeks. In the 25th week, proctocolectomy was conducted. PRO alone and PRO combined with PS were the best intervention strategies to improve experimental 1,2-DMH-induced CRC regarding several parameters of carcinogenesis. Our findings may contribute to the development of novel preventive strategies for CRC and may help to identify novel modulators of colon carcinogenesis.

13.
Med Oncol ; 40(5): 143, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37040017

RESUMO

Investigations that decipher the human microbiome have reformed the way medicine is focusing on bacteria. An interesting research review recently published in the journal of Digestive Diseases and Sciences conceivably linked adjunctive commensal intestinal bacteria with the capacity to modulate the immune microenvironment towards immune checkpoint inhibitor (ICIs) efficacy of cancer immunotherapy. Evidence has emerged that the intestinal microbiome can modulate outcomes to ICIs therapies via two major mechanisms, namely mechanisms that are antigen-specific (i.e., epitopes are shared between microbial and tumour antigens that can enhance or reduce anti-tumour immune responses) and those mechanisms that are antigen-independent (i.e., modulation of responses to ICIs by engaging innate and/or adaptive immune cells).


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Imunoterapia , Microambiente Tumoral
14.
Foods ; 12(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36900505

RESUMO

Perilla frutescens (PF) seed residue is a waste from perilla oil production that still contains nutrients and phytochemicals. This study aimed to investigate the chemoprotective action of PF seed residue crude ethanolic extract (PCE) on the inflammatory-induced promotion stage of rat colon carcinogenesis and cell culture models. PCE 0.1 and 1 g/kg body weight were administered by oral gavage to rats after receiving dimethylhydrazine (DMH) with one week of dextran sulfate sodium (DSS) supplementation. PCE at high dose exhibited a reduction in aberrant crypt foci (ACF) number (66.46%) and decreased pro-inflammatory cytokines compared to the DMH + DSS group (p < 0.01). Additionally, PCE could either modulate the inflammation induced in murine macrophage cells by bacterial toxins or suppress the proliferation of cancer cell lines, which was induced by the inflammatory process. These results demonstrate that the active components in PF seed residue showed a preventive effect on the aberrant colonic epithelial cell progression by modulating inflammatory microenvironments from the infiltrated macrophage or inflammatory response of aberrant cells. Moreover, consumption of PCE could alter rat microbiota, which might be related to health benefits. However, the mechanisms of PCE on the microbiota, which are related to inflammation and inflammatory-induced colon cancer progression, need to be further investigated.

15.
Acta cir. bras ; 38: e383623, 2023. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1513537

RESUMO

Purpose: To analyze the potential of tumor necrosis factor-α (TNF-α) and factor nuclear kappa B (NF-κB) as colorectal cancer (CRC) biomarkers in an experimental model of intestinal carcinogenesis with 1,2-dimethyhydrazine (1,2-DMH). Methods: Twenty-four male Wistar rats were divided into two groups: sham and 1,2-DMH. First, 1,2-DMH (20 mg/kg/week) was administered for 15 consecutive weeks. In the 25th week, proctocolectomy was conducted. Histopathological analysis, immunohistochemistry, and gene expression of TNF-α and NF-κB were performed. Statistical analysis was performed using GraphPad Prism. The location of aberrant crypt foci (ACF) was analyzed by Kruskal-Wallis' test. For analyses with two groups with parametric data, the t-test was used; for non-parametric data, the Mann-Whitney's test was used. P < 0.05 was considered significant. Results: The number of ACF and macroscopic lesions was significantly higher (p < 0.5) in the 1,2-DMH group compared to the sham group, and most ACF were concentrated in the distal segment of the colon. There was a statistically significant increase (p < 0.5) in protein and gene expression of TNF-α and NF-κB in the 1,2-DMH group compared to the sham group. Conclusions: Our results provide supportive evidence that TNF-α and NF-κB pathways are strongly involved in CRC development in rats and might be used as early biomarkers of CRC pathogenesis in experimental studies.


Assuntos
Animais , Ratos , Biomarcadores Tumorais , NF-kappa B , Fator de Necrose Tumoral alfa , Ratos Wistar , Carcinogênese
16.
Antioxidants (Basel) ; 11(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36552579

RESUMO

Colorectal cancer (CRC), associated with an increased intake of processed red meats, saturated fats, and simple carbohydrates accompanied by low dietary fiber, fruits, and vegetables consumption, presents a high epidemiological burden. Connexin43 (Cx43) protein, which forms gap junctions or hemichannels, has tumor suppressor or oncogenic activities in a cancer type- and stage-dependent manner. Cx43 expression varies during colon carcinogenesis, and its functional role is not fully understood. Thus, we evaluated the implications of Cx43 heterologous deletion (Cx43+/-) during the early stages of a chemically induced model of colon carcinogenesis. Female C57BL/6J mice (wild-type or Cx43+/-) were submitted to a colon carcinogenesis model induced by 1,2 dimethylhydrazine (DMH). Mice were euthanized eight hours (week 7) or 30 weeks (week 37) after the last DMH administration to evaluate subacute colon toxicity outcomes or the burden of (pre)neoplastic lesions, respectively. At week 7, Cx43 deficiency inferred no alterations in the DMH-induced increase in systemic (peripheral blood), in situ (colonocytes) DNA damage, and apoptosis in the colonocytes. At week 30, Cx43+/- mice presented an increase in preneoplastic aberrant crypt foci (ACF) multiplicity, while no alterations were observed in colorectal adenoma (CRA) occurrence, multiplicity, volume, proliferation, growth, and ß-catenin immunoexpression. Similarly, an in silico analysis of human CRA showed decreased mRNA expression of Cx43 with no correlation with proliferation, apoptosis, and ß-catenin markers. These findings indicate the discrete role of Cx43 in the early stages of chemically induced mouse colon carcinogenesis.

17.
Medicina (Kaunas) ; 58(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36556972

RESUMO

Background and Objectives: Aberrant crypt foci (ACF) are one of the earliest putative preneoplastic and, in some cases, neoplastic lesions in human colons. Many studies have confirmed the reduction of ACFs and colorectal adenomas after treatment with acetylsalicylic acid (ASA) commonly referred to as ASA; however, the minimum effective dose of ASA and the duration of use has not been fully elucidated. The objective of our study was to assess the significance of low dose ASA (75-mg internally once daily) to study the chemopreventive effect of ASA in ACF and adenomas development in patients taking this drug for a minimum period of 10 years. Materials and Methods: Colonoscopy, combined with rectal mucosa staining with 0.25% methylene blue, was performed on 131 patients. The number of rectal ACF in the colon was divided into three groups: ACF < 5; ACF 5−10; and ACF > 10. Patients were divided into two groups: the "With ASA" group (the study group subjects taking ASA 75-mg daily for 10 years); and "Without ASA" group (control group subjects not taking ASA chronically). The incidence of different types of rectal ACF and colorectal polyps in both groups of subjects was analysed and ascertained. Results: Normal ACF was found in 12.3% in the study group vs. 87.7% control group, hyperplastic 22.4% vs. 77.6%, dysplastic 25% vs. 75%, mixed 0% vs. 100%. Treatment with ASA affects the occurrence of colorectal adenomas. The amount of dysplastic ACFs was lower in the study group than in the control group. The increase in dysplastic ACFs decreases with age in both groups, with the increase greater in those not taking ASA. Conclusions: Patients who take persistent, chronic (>10 years) low doses of ASA have a lower total number of all types of rectal ACFs and adenomas compared to the control group.


Assuntos
Focos de Criptas Aberrantes , Adenoma , Neoplasias Colorretais , Humanos , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/epidemiologia , Focos de Criptas Aberrantes/patologia , Aspirina/uso terapêutico , Reto , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/tratamento farmacológico , Adenoma/prevenção & controle , Adenoma/patologia
18.
Biomedicines ; 10(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36428460

RESUMO

High-fat diet (HFD)-induced obesity is a risk factor for colon cancer. Our previous data show that compared to an AIN-93 diet (AIN), a HFD promotes azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) formation and microbial dysbiosis in C57BL/6 mice. To explore the underlying metabolic basis, we hypothesize that AOM treatment triggers a different fecal metabolomic profile in C57BL/6 mice fed the HFD or the AIN. We found that 65 of 196 identified metabolites were significantly different among the four groups of mice (AIN, AIN + AOM, HFD, and HFD + AOM). A sparse partial least squares discriminant analysis (sPLSDA) showed that concentrations of nine fecal lipid metabolites were increased in the HFD + AOM compared to the HFD, which played a key role in overall metabolome group separation. These nine fecal lipid metabolite concentrations were positively associated with the number of colonic ACF, the cell proliferation of Ki67 proteins, and the abundance of dysbiotic bacteria. These data suggest that the process of AOM-induced ACF formation may increase selective fecal lipid concentrations in mice fed with a HFD but not an AIN. Collectively, the accumulation of these critical fecal lipid species may alter the overall metabolome during tumorigenesis in the colon.

19.
Probiotics Antimicrob Proteins ; 14(3): 407-414, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35112298

RESUMO

Previous studies have reported that dietary sphingomyelin could inhibit early stages of colon cancer. Lactic acid-producing bacteria have also been associated with an amelioration of cancer symptoms. However, little is known about the potential beneficial effects of the combined administration of both sphingomyelin and lactic acid-producing bacteria. This article analyzes the effect of a diet supplemented with a combination of the probiotics Lacticaseibacillus casei and Bifidobacterium bifidum (108 CFU/ml) and sphingomyelin (0.05%) on mice with 1,2-dimethylhydrazine (DMH)-induced colon cancer. Thirty-six BALB/c mice were divided into 3 groups: one healthy group (group C) and two groups with DMH-induced cancer, one fed a standard diet (group D) and the other fed a diet supplemented with sphingomyelin and probiotics (DS). The number of aberrant crypt foci, marker of colon cancer development, was lower in the DS. The dietary supplementation with the synbiotic reversed the cancer-induced impairment of galactose uptake in enterocyte brush-border-membrane vesicles. These results confirm the beneficial effects of the synbiotic on the intestinal physiology of colon cancer mice and contribute to the understanding of the possible mechanisms involved.


Assuntos
Neoplasias do Colo , Probióticos , Animais , Camundongos , Neoplasias do Colo/induzido quimicamente , Dieta , Ácido Láctico , Probióticos/farmacologia , Esfingomielinas/efeitos adversos
20.
Bol. latinoam. Caribe plantas med. aromát ; 21(1): 66-80, ene. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1372378

RESUMO

Melastoma malabathricum (M. malabathricum) extracts have been reported to exert various pharmacological activities including antioxidants, anti-inflammatory and antiproliferative activities. The objective of the present study was to determine the anticarcinogenic activity of its methanol extract (MEMM) against the azoxymethane (AOM)-induced early colon carcinogenesis in rats. Rats were randomly assigned to five groups (n=6) namely normal control, negative control, and treatment (50, 250 or 500 mg/kg of MEMM) groups. Colon tissues were harvested for histopathological analysis and endogenous antioxidant system determination. MEMM was also subjected to HPLC analysis. Findings showed that MEMM significantly (p<0.05) reversed the AOM-induced carcinogenicity by: i) reducing the formation of aberrant crypt foci (ACF) in colon tissues, and; ii) enhancing the endogenous antioxidant activity (catalase, superoxide dismutase and glutathione peroxidase). Moreover, various phenolics has been identified in MEMM. In conclusion, MEMM exerts the in vivo anticarcinogenic activity via the activation of endogenous antioxidant system and synergistic action of phenolics.


Se ha informado que los extractos de Melastoma malabathricum (M. malabathricum) ejercen diversas actividades farmacológicas, incluidas actividades antioxidantes, antiinflamatorias y antiproliferativas. El objetivo del presente estudio fue determinar la actividad anticancerígena de su extracto de metanol (MEMM) contra la carcinogénesis de colon temprana inducida por azoximetano (AOM) en ratas. Las ratas se asignaron al azar a cinco grupos (n=6), a saber, los grupos de control normal, control negativo y tratamiento (50, 250 o 500 mg/kg de MEMM). Tejidos de colon fueron recolectados para análisis histopatológico y determinación del sistema antioxidante endógeno. MEMM también se sometió a análisis de HPLC. Los hallazgos mostraron que MEMM invirtió significativamente (p<0.05) la carcinogenicidad inducida por AOM al: i) reducir la formación de focos de criptas aberrantes (ACF) en los tejidos del colon, y; ii) potenciar la actividad antioxidante endógena (catalasa, superóxido dismutasa y glutatión peroxidasa). Además, se han identificado varios fenólicos en MEMM. En conclusión, MEMM ejerce la actividad anticancerígena in vivo mediante la activación del sistema antioxidante endógeno y la acción sinérgica de los fenólicos.


Assuntos
Animais , Ratos , Extratos Vegetais/administração & dosagem , Anticarcinógenos/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Melastomataceae/química , Tamanho do Órgão/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ratos Sprague-Dawley , Colo/patologia , Folhas de Planta , Metanol , Compostos Fenólicos , Focos de Criptas Aberrantes , Carcinogênese/efeitos dos fármacos , Antioxidantes
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