RESUMEN
BACKGROUND: Brazilian berry is a fruit popularly known as "Jaboticaba," rich in bioactive compounds with antioxidant and anti-inflammatory properties. Senescence and overweight are increasing worldwide and are considered risk factors to prostatic pathogenesis mainly due to oxidative and inflammatory processes induction. Thus, this study aimed to evaluate the effect of two increasing doses of the patented jaboticaba peel extract (PJE) on oxidative-stress and inflammation in the prostate of aging or high-fat-fed aging mice. METHODS: PJE and/or high-fat diet (HFD) treatments started with 11-month-old mice and lasted 60 days. The levels or the immunoexpression of different inflammatory (nuclear factor κB [NFκB], CD3+, cyclooxygenase 2 [COX-2], toll-like receptor 4 [TLR4], phosphorylated signal transducers and activators of transcription 3 [pSTAT-3], tumor necrosis factor α [TNF-α], interleukin 6 [IL-6], and IL-1ß) and oxidative-stress (catalase, superoxide dismutase 2 [SOD2], glutathione reductase [GSR], reduced glutathione, and glutathione peroxidase 3 [GPx3]) related molecules were analyzed by western-blotting, immunohistochemistry, and enzyme-linked immunosorbent assays. RESULTS: Both PJE doses reduced the levels of oxidative-stress-related molecules (GPx3, GSR, catalase), lipid peroxidation (4-hydroxynonenal), inflammatory mediators (COX-2, TNF-α, and pSTAT-3) and CD3+ T cells number, which were associated with the maintenance of the glandular morphological integrity in aging and HFD-fed-aging mice. Nevertheless, only the high PJE dose reduced the NFκB and TLR4 levels in aging mice; and SOD2, IL-6, and IL-1ß levels in HFD-aging mice. Aging itself promoted an oxidative inflammation in the prostate, interfering in the levels of the different oxidative-stress, lipid peroxidation, and inflammatory mediators evaluated, in association with high incidence of prostate epithelial and stromal damages. The HFD intake intensified aging alterations, showing an unfavorable prostatic microenvironment prone to oxidative and inflammatory damages. CONCLUSIONS: PJE exerted a dose-dependent effect controlling inflammation and oxidative-stress in aging and HFD-fed aging mice prostate. This fact contributed to prostate microenvironment balance recovery, preserving the tissue architecture of this gland. Thus, the PJE emerges as a potential therapy to prevent inflammation and oxidative stress in the prostate.
Asunto(s)
Frutas/química , Myrtaceae/química , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Prostatitis/tratamiento farmacológico , Factores de Edad , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Ciclooxigenasa 2/biosíntesis , Ciclooxigenasa 2/inmunología , Dieta Alta en Grasa , Relación Dosis-Respuesta a Droga , Interleucina-1beta/sangre , Interleucina-6/sangre , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Extractos Vegetales/química , Prostatitis/inmunología , Prostatitis/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunologíaRESUMEN
Prostate cancer (PCa) progression mechanism has been linked to epithelial proliferation, tumor invasion ability, and growth factors. Nintedanib (BIBF 1120) has been reported as being FGF and VEGF pathway inhibitors, exhibiting antitumor activity. Thus, the objective herein was to characterize the early Nintedanib treatment effects on the structure and molecules involved in the basal membrane, the extracellular matrix (ECM) maintenance, in addition to the angiogenesis and mitogenic processes at different grades of prostatic tumor development in TRAMP mice. Therefore, 45 male TRAMP mice were divided into control groups: 8-week-old mice (TC8), 12-week-old mice (TC12), and 16-week-old mice (TC16); and treated groups with 10 mg/kg/day Nintedanib dose for 4 weeks. The treated groups were euthanized at 12 (TN12) and 16 (TN16) weeks of age. Samples from the dorsolateral lobe were collected and processed for light microscopy, immunohistochemistry, Western blotting, and microvessel density analysis. The results showed that early Nintedanib treatment led to an increase of healthy epithelium frequency and a reduction of LGPIN and a maximum vascularization density in the TN12 group. Also, treatment led to a well-differentiated adenocarcinoma decrease and an α and ß dystroglycan and also laminin 1 increase in the TN16 group. IGFR1 decreased in the TN16 group. To conclude, early Nintedanib treatment led to a reduction in cancer severity, interfering in both ECM compounds and angiogenesis process to then contribute to a balance, not only in the prostatic epithelium and stroma, but also in the epithelial-stromal interaction during PCa progression.
Asunto(s)
Antineoplásicos/uso terapéutico , Indoles/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Proliferación Celular/efectos de los fármacos , Progresión de la Enfermedad , Distroglicanos/análisis , Epitelio/química , Epitelio/patología , Laminina/análisis , Masculino , Ratones Transgénicos , Próstata/efectos de los fármacos , Próstata/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Células del Estroma/clasificación , Células del Estroma/patologíaRESUMEN
Ethanol alters motricity, learning, cognition, and cellular metabolism in the cerebellum. The combination of ethanol with caffeine by consuming "energy drinks" is becoming increasingly popular among young people. We analyzed the use of ethanol and caffeine on apoptosis in the cerebellum of UChB rats. The adult rats were divided into three groups (n = 14/group): UChB group: rats fed with 1:10 (v/v) ethanol ad libitum (free choice for water or ethanol) drinking from >1.9 mL of ethanol/kg body weight/day, Control group and UChB/caffeine group (free choice for water or ethanol + caffeine 300 mg/L). The treatments occurred from Day 100 till Day 150, totalizing 50 days of ethanol/caffeine ingestion. Cerebellar sections were subjected to immunohistochemistry and gene expression for Real Time-PCR (RT-PCR) for Caspase-3, XIAP, and insulin-like growth factor 1-receptor (IGF-1R). The results showed a significant increase in the gene expression of Caspase-3 and XIAP in UChB group. On the other hand, the animals of the UChB/caffeine group showed similar results to the Controls. Regarding IGFR-1, there was greater expression in the UChB groups with strong labeling in Purkinje cells. Ethanol produces neuronal and glial neurodegeneration on the cerebellum of UChB rats. The simultaneous ingestion of ethanol and caffeine reversed the ethanol damages acting caffeine with a neuroprotective effect.
Asunto(s)
Apoptosis/efectos de los fármacos , Cafeína/farmacología , Cerebelo/patología , Etanol/farmacología , Animales , Caspasa 3/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Ratas Wistar , Receptor IGF Tipo 1/metabolismo , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismoRESUMEN
BACKGROUND: Prostate cancer is associated to a reactive stroma microenvironment characterized by angiogenic processes that are favorable for tumor progression. Senescence has been identified as a predisposing factor for prostate malignancies. In turn, the relationships between aging, reactive stroma, and the mechanisms that induce this phenotype are largely unknown. Thus, we investigated the occurrence of reactive stroma in the mouse prostate during advanced age as well as the effects of antiangiogenic and androgen ablation therapies on reactive stroma recruitment. METHODS: Male mice (52-week-old FVB) were treated with two classes of angiogenesis inhibitors: direct (TNP-470; 15 mg/kg; s.c.) and/or indirect (SU5416; 6 mg/kg; i.p.). Androgen ablation was carried out by finasteride administration (20 mg/kg; s.c.), alone or in association to both inhibitors. The Transgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model was used as a paradigm of cancer-associated reactive stroma. The dorsolateral prostate was collected for α-actin (αSMA), vimentin (VIM), and transforming growth factor-beta (TGF-ß) immunohistochemical and Western blotting analyses as well as for CD34/αSMA and CD34/VIM colocalization. RESULTS: Senescence was associated with increased αSMA, VIM, and TGF-ß expression as well as with the recruitment of CD34/αSMA and CD34/VIM dual-positive fibroblasts. These observations were similar to those verified in TRAMP mice. Antiangiogenic treatment promoted the recovery of senescence-associated stromal changes. Hormonal ablation, despite having led to impaired CD34/αSMA and CD34/VIM dual-positive cell recruitment, did not result in decreased stimulus to reactive stroma development, due to enhanced TGF-ß expression in relation to the aged controls. CONCLUSIONS: Reactive stroma develops in the prostate of non-transgenic mice as a result of aging. The periacinar microvasculature is a candidate source for the recruitment of reactive stroma-associated cells, which may be derived either from perivascular-resident mesenchymal stem cells (MSCs) or from an endothelial-to-mesenchymal transition (EndMT) process. Thus, antiangiogenic therapy is a promising approach for preventing age-associated prostate malignancies by means of its negative interference in the development of reactive stroma phenotype from the vascular wall.
Asunto(s)
Envejecimiento/patología , Inhibidores de la Angiogénesis/farmacología , Microvasos/patología , Próstata/irrigación sanguínea , Próstata/patología , Factores de Edad , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Finasterida/farmacología , Finasterida/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microvasos/efectos de los fármacos , Próstata/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/patologíaRESUMEN
PURPOSE: We compared and characterized the effects of intravesical bacillus Calmette-Guérin and/or staphylococcal enterotoxin B for nonmuscle invasive bladder cancer. MATERIALS AND METHODS: A total of 75 female Fisher 344 rats were anesthetized. Of the rats 15 received 0.3 ml saline (control) and 60 received 1.5 mg/kg MNU (N-methyl-n-nitrosourea) intravesically every other week for 6 weeks. The rats were divided into 5 groups. The MNU and control groups received 0.3 ml saline. The bacillus Calmette-Guérin group received 10(6) cfu bacillus Calmette-Guérin. The staphylococcal enterotoxin B group received 10 µg/ml staphylococcal enterotoxin B. The bacillus Calmette-Guérin plus staphylococcal enterotoxin B group received the 2 treatments simultaneously. Each group was treated intravesically for 6 weeks. At 15 weeks all bladders were collected for histopathological and immunological evaluation, and Western blot. RESULTS: Papillary carcinoma (pTa) and high grade intraepithelial neoplasia (carcinoma in situ) were more common in the MNU group. Papillary hyperplasia was more common in the bacillus Calmette-Guérin and enterotoxin groups. Flat hyperplasia was more common in the bacillus Calmette-Guérin plus enterotoxin group. No significant toxicity was observed. The apoptosis and cellular proliferation indexes decreased in the bacillus Calmette-Guérin, enterotoxin and bacillus Calmette-Guérin plus enterotoxin groups compared to the MNU group. Intensified vascular endothelial growth factor, matrix metalloproteinase-9, Ki-67 and insulin-like growth factor receptor-1 immunoreactivity was verified in the MNU group, moderate in the bacillus Calmette-Guérin and enterotoxin groups, and weak in the bacillus Calmette-Guérin plus enterotoxin and control groups. In contrast, intense endostatin immunoreactivity was verified in the control and bacillus Calmette-Guérin plus enterotoxin groups. CONCLUSIONS: Bacillus Calmette-Guérin and staphylococcal enterotoxin B showed similar anti-angiogenic effects. Bacillus Calmette-Guérin plus enterotoxin treatment had additional activity compared to that of monotherapy. It was more effective in restoring apoptosis and balancing cellular proliferation, and it correlated with increased endostatin, and decreased vascular endothelial growth factor, matrix metalloproteinase-9, Ki-67 and insulin-like growth factor receptor-1 reactivity.
Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Vacuna BCG/uso terapéutico , Enterotoxinas/uso terapéutico , Staphylococcus aureus/inmunología , Superantígenos/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Animales , Femenino , Invasividad Neoplásica , Ratas , Ratas Endogámicas F344 , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
Diabetes causes harmful effects on prostatic morphology and function. However, there still are doubts about the occurrence of various diseases in the prostate, as well as abnormal angiogenesis in relation to diabetes. Thus, the aim of this study was to correlate and quantify the level of the steroid hormone receptors and the angiogenic and antiangiogenic factors in non-obese diabetic mice (Nod) after combined hormonal and insulin therapy. Sixty mice were divided into six groups after 20 days of diabetes: the control group received 0.9% NaCl, as did the diabetic group. The diabetic-insulin group received insulin, the diabetic-testosterone group received testosterone cypionate, the diabetic-oestrogen group received 17ß-oestradiol, and the diabetic-insulin-testosterone-oestrogen group received insulin, testosterone and oestrogen simultaneously. After 20 days, the ventral lobe was processed for immunocytochemical and hormonal analyses. The results showed that the lowest serum testosterone and androgen receptor levels were found in the diabetic group and the highest testosterone and androgen receptor levels in the diabetic-insulin-testosterone-oestrogen group. The serum oestrogen level and its receptor showed changes opposite to those of testosterone and its receptor. The endostatin reactivity was mainly decreased in diabetic mice. The greatest IGFR-1 and VEGF reactivities occurred in diabetic mice. Thus, diabetes led to the prostatic hormonal imbalance, affecting molecular dynamics and angiogenesis in this organ. Combined insulin and steroid hormone therapy partially restored the hormonal and angiogenic imbalance caused by diabetes.
Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Estradiol/farmacología , Insulina/farmacología , Próstata/efectos de los fármacos , Receptores de Esteroides/metabolismo , Transducción de Señal/efectos de los fármacos , Testosterona/análogos & derivados , Análisis de Varianza , Animales , Western Blotting , Diabetes Mellitus Experimental/metabolismo , Estradiol/uso terapéutico , Inmunohistoquímica , Insulina/uso terapéutico , Masculino , Ratones , Ratones Endogámicos NOD , Próstata/metabolismo , Receptor IGF Tipo 1/metabolismo , Testosterona/farmacología , Testosterona/uso terapéuticoRESUMEN
The prostate is fundamental to the male reproductive process, and the stroma-epithelium interaction has an important role in prostate maintenance. Studies suggest that dystroglycan (DG) plays a role in cancer development in various organs. Thus, the aims of this work were to characterize morphological and proliferative features of the prostatic stroma and epithelium of mdx mice; to verify the immunolocalization of the α and ß DG, IGF-1 and laminin α3 receptors; and to relate those structural and molecular events to prostate pathogenesis and to verify the viability of this experimental model in prostate studies. Thirty male mice (mdx and C57BL10/Uni) were divided into control and mdx groups. Samples from the ventral prostate were collected for immunological, Western Blotting, transmission electron microscopy and morphometric analyses. Oestradiol and testosterone measurements were verified. The results showed diminished testosterone and increased oestradiol levels in the mdx group. Atrophied cells and hypertrophied stroma were seen in the mdx mice. Weak α and ß DG and laminin α3 immunolocalization was demonstrated in the mdx group. Intense insulin-like growth factor receptor α-1 (IGFRα-1) localization was identified in the mdx animals. Thus, mdx animals showed changes in molecular and structural integrity and proliferation signals, leading to glandular homoeostasis imbalance, and compromise of prostate function. Also, the steroid hormone imbalance and the increased IGF-1 receptor level detected in mdx mice could be considered as a crucial factor in the pathogenesis of prostatic disorders.
Asunto(s)
Modelos Animales de Enfermedad , Ratones Endogámicos mdx , Distrofia Muscular Animal/patología , Próstata/patología , Enfermedades de la Próstata/patología , Animales , División Celular/fisiología , Distroglicanos/metabolismo , Estradiol/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Distrofia Muscular Animal/complicaciones , Distrofia Muscular Animal/fisiopatología , Próstata/fisiología , Próstata/ultraestructura , Enfermedades de la Próstata/etiología , Enfermedades de la Próstata/fisiopatología , Testosterona/sangreRESUMEN
PURPOSE: No optimal, well designed and reproducible animal model for upper urothelial carcinogenesis exists. This study characterized the histopathological features on top of immunolocalization of alpha-dystroglycans (alpha-DG) and matrix metalloproteinase (MMP-9) and cell turn-over in the upper urinary tract using a novel experimental model. METHODS: Seventy-five female Fischer 344 rats were divided into three groups: the control group received a 0.30-ml dose of 0.9% physiological saline; the MNU group (chemical carcinogen N-methyl-N-nitrosourea) received 0.30 ml of MNU; and the MNU-citrate group received 0.30 ml of MNU plus sodium citrate, every one intravesically every other week for a total of 4 doses. After 15 weeks, bladder, ureters and renal pelvis were collected for morphological and molecular analysis. RESULTS: Associated management with MNU and sodium citrate was able to lead to 100% of both urinary bladder and upper urinary tract tumors, being the high-grade noninvasive papillary urothelial carcinoma the most frequent lesion. The upper urothelium showed reduced alpha-DG and increased MMP-9 and Ki-67 immunoreactivities in the MNU-citrate group in relation to the other groups. MNU group presented no upper urothelium tumor and 100% bladder tumor. CONCLUSIONS: This is a relevant evolution on experimental animal model for upper urinary tract carcinogenesis field. MMP-dependent disruption of the DG complex plays an important role in urothelial tumor carcinogenesis and showed the model applicability and significance. MNU-citrate model could contribute to a better understanding of human upper urothelial cancer development as well as to its local treatment strategies in a near future.
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Modelos Animales de Enfermedad , Ratas Endogámicas F344 , Neoplasias Urológicas/patología , Urotelio/patología , Alquilantes/toxicidad , Animales , Biopsia , Citratos/toxicidad , Femenino , Médula Renal/diagnóstico por imagen , Médula Renal/patología , Metilnitrosourea/toxicidad , Ratas , Citrato de Sodio , Uréter/diagnóstico por imagen , Uréter/patología , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patología , Urografía , Neoplasias Urológicas/inducido químicamente , Neoplasias Urológicas/diagnóstico por imagen , Urotelio/diagnóstico por imagenRESUMEN
The consumption of alcohol or nicotine is harmful to the integrity of bone tissue, hindering or even impeding the fixation and maintenance of bone implants. The aim of the present work was to evaluate the effects of ethanol and nicotine, when consumed alone and simultaneously, on both bone mechanical resistance and bone neoformation around hydroxyapatite implants. Twenty rats were divided into four groups: control (CT), alcohol (A), nicotine (N) and nicotine + alcohol (N + A). After 4 weeks of alcohol and/or nicotine consumption, dense (HAD) and porous (HAP) bodies were respectively implanted in a surgically produced bone defect in the right and left tibiae. After the surgeries, the animals continued to consume alcohol and/or nicotine. After ninety days, the animals were sacrificed and the tibiae and femurs were isolated for histological processing and mechanical assays. All the animals presented newly formed bone tissue close to the HAD and HAP ceramic bodies. The animals of the N + A group presented a smaller volume of neoformed bone. Group A animals presented smaller bone volume around the implants in relation to the animals from group N. Bone resistance to mechanical loads was smallest in animals from the N + A group, followed (in order) by the A and N groups. Thus, it can be concluded that nicotine or alcohol consumption produced negative effects on bone mechanical resistance and on the osteogenesis around the HAD and HAP implants. In addition, the simultaneous consumption of the two substances intensified their harmful effects.
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Huesos/efectos de los fármacos , Durapatita , Etanol/toxicidad , Implantes Experimentales , Nicotina/toxicidad , Oseointegración/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Huesos/lesiones , Huesos/patología , Calcio/sangre , Dieta , Combinación de Medicamentos , Masculino , Porosidad , Ratas , Estrés Mecánico , Tibia/efectos de los fármacos , Tibia/lesiones , Tibia/patologíaRESUMEN
Senescence is one of the main aetiological factors which are responsible for natural androgen ablation in men and occurrence of prostatic diseases. However, it is unclear how the prostatic lesions are signallised in the prostate. Thus, the aim of this study is to characterise the structural, the ultrastructural and the proliferative aspects of the peripheral prostatic zone in the elderly men with and without diagnoses of prostatic lesions and with potential precursors of prostate cancer. Sixty samples of prostatic tissue, from 60 to 90-year-old patients with and without lesions obtained from autopsied or prostatectomised patients were divided into four groups (15 samples per group): standard group (no lesions), benign prostatic hyper-plasia group, high-grade prostatic intra-epithelial neoplasia group and prostatic carcinoma group. The samples were submitted to morphometrical, structural and ultrastructural analyses in addition to cellular apoptosis and proliferative analyses. The results showed morphological damages in the stroma and cellular organelles involved in the secretory process of the prostate. Moreover, the prostatic lesions in elderly men demonstrated disturbance in the proliferation/apoptosis rate, indicating a prevalence of the proliferative process. Finally, the imbalance in prostatic stroma-epithelium interaction was a harmful feature in the elderly men as a result of structural changes, which are crucial factors for the development and progression of carcinogenesis.
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Envejecimiento/patología , Enfermedades de la Próstata/patología , Anciano , Anciano de 80 o más Años , Apoptosis , Proliferación Celular , Humanos , Antígeno Ki-67/inmunología , Masculino , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Próstata/patología , Próstata/ultraestructura , Hiperplasia Prostática/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/ultraestructuraRESUMEN
Goniothalamin (GTN), a natural compound isolated from Goniothalamus species, has previously demonstrated cytotoxic activity against several cancer cell lines. However, similarly to many natural and synthetic anticancer compounds, GTN presents toxicity toward some healthy cells and low aqueous solubility, decreasing its bioavailability and precluding its application as an antineoplastic drug. In our efforts to improve the pharmacokinetic behavior and selectivity of GTN against cancer cells, we developed a polymeric nanosystem, in which rac-GTN was encapsulated in pH-responsive acetalated dextran (Ac-Dex) nanoparticles (NPs) with high loadings of the bioactive compound. Dynamic light scattering (DLS) analysis showed that the nanoparticles obtained presented a narrow size distribution of around 100 nm in diameter, whereas electron microscopy (EM) images showed nanoparticles with a regular spherical morphology in agreement with the size range obtained by DLS. Stability and release studies indicated that the GTN@Ac-Dex NPs presented high stability under physiological conditions (pH 7.4) and disassembled under slightly acidic conditions (pH 5.5), releasing the rac-GTN in a sustained manner. In vitro assays showed that GTN@Ac-Dex NPs significantly increased cytotoxicity and selectivity against cancer cells when compared with the empty Ac-Dex NPs and the free rac-GNT. Cellular uptake and morphology studies using MCF-7 cells demonstrated that GTN@Ac-Dex NPs are rapidly internalized into the cancer cells, causing cell death. In vivo investigation confirmed the efficient release of rac-GTN from GTN@Ac-Dex NPs, resulting in the delay of prostate cancer progression in transgenic adenocarcinoma of the mouse prostate (TRAMP) model. Furthermore, liver histopathology evaluation after treatment with GTN@Ac-Dex NPs showed no evidence of toxicity. Therefore, the in vitro and in vivo findings suggest that the Ac-Dex NPs are a promising nanosystem for the sustained delivery of rac-GTN into tumors.
Asunto(s)
Dextranos , Nanopartículas , Animales , Humanos , Concentración de Iones de Hidrógeno , Ratones , Pironas/farmacologíaRESUMEN
Most phenolic compounds and dietary fiber reach intact to the colon. We hypothesized that grape peel powder (GPP), a rich source of these bioactive compounds, modulates inflammatory and oxidative pathways collaborating to attenuate colonic damage in experimental colitis. To determine which bioactive fraction would be responsible for this effect, the aim of this study was to evaluate the effect of dietary supplementation with whole GPP or the isolated bioactive-rich fractions from GPP (extractable polyphenols [EP], dietary fiber and fiber-bound polyphenols [NEP-F], and dietary fiber) in rats with experimental colitis. Colitis was induced by intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS) after 15â¯days of dietary supplementation. EP diet did not reverse the decrease in feed intake and indeed worsened colon shortening and increased spleen weight; however, these effects were not observed for the GPP group, which had polyphenols associated to the matrix besides the extractable ones. Colitis impaired the activity of colonic antioxidant enzymes and increased lipid peroxidation, protein oxidation, nitric oxide (NO) levels, and proinflammatory cytokines in serum and in the colon tissue. GPP restored the activity of antioxidant enzymes and decreased colon oxidation and NO levels. All grape peel fractions reduced the protein expression of the inhibitor of kappa kinase beta and NO levels in colon tissue, but only NEP-F reduced the expression of phosphorylated nuclear factor kappa B and myeloperoxidase activity. Results demonstrated that GPP attenuates inflammatory and oxidative response in TNBS-induced colitis by downregulating the nuclear factor kappa B pathway and upregulating antioxidant enzymes, with NEP-F being the fraction most likely associated to these protective effects.