Effects of oral butyrate and inulin supplementation on inflammation-induced pyroptosis pathway in type 2 diabetes: A randomized, double-blind, placebo-controlled trial.

PURPOSE: Pyroptosis, a form of inflammatory programmed cell death, is activated in diabetic patients. This study was conducted to investigate the effects of daily consumption of sodium butyrate (NaBut) and high-performance (HP) inulin supplementation, individually or in combination, on the expression of pyroptosis-related genes, microRNA (miR) 146a-5p, miR-9-5p and biomarkers of oxidative stress in patients with type 2 diabetes (T2DM). METHODS: In this study, we conducted a randomized, double-blinded, placebo-controlled clinical involving sixty patients with type 2 diabetes. Participants received 600 mg/d of NaBut (group A), 10 g/d of HP inulin (group B), 600 mg/d of NaBut + 10 g/d of HP inulin (group C) or placebo (group D) for 45 consecutive days. We assessed the pyroptosis-related genes mRNA expression in peripheral blood mononuclear cells (PBMCs), as well as the plasmatic levels of miR-146a and miR-9 before and after the intervention. Moreover, blood samples of the patients at baseline and following the intervention were tested for total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase levels using enzyme-linked immunosorbent assay (ELISA). This study was registered on the Iranian Registry of Clinical Trials website (identifier: IRCT201605262017N29; https://www.irct.ir/). RESULTS: Following butyrate supplementation, the relative expression levels of TLR2/4, NF-κB1, Caspase-1, NLRP3, IL-1ß & IL-18 were significantly downregulated (p < 0.05). Furthermore, butyrate and concomitant use of butyrate and inulin caused a significant increase in the fold change of miR-146a and miR-9 compared with the placebo group (p < 0.05). Interestingly, the changes in total antioxidant capacity (p = 0.047) and superoxide dismutase (p = 0.006) were significantly increased after butyrate and concomitant use of butyrate and inulin supplement, respectively. CONCLUSION: In summary, the change in expression level of miR-146a-5p and miR-9-5p due to butyrate supplementation may have a pivotal role in alleviating of diabetes via inhibiting pyroptosis by targeting TLR2 and NF-κB1. These microRNAs might be considered as potential therapeutic targets in the treatment of type 2 diabetes but further researches is required to prove the link.

Co-delivery of curcumin and Bcl-2 siRNA by PAMAM dendrimers for enhancement of the therapeutic efficacy in HeLa cancer cells.

Co-delivery of therapeutic agents and small interfering RNA (siRNA) can be achieved by a suitable nanovehicle. In this work, the solubility and bioavailability of curcumin (Cur) were enhanced by entrapment in a polyamidoamine (PAMAM) dendrimer, and a polyplex was formed by grafting Bcl-2 siRNA onto the surface amine groups to produce PAMAM-Cur/Bcl-2 siRNA nanoparticles (NPs). The synthesized polyplex NPs had a particle size of ∼180 nm, and high Cur loading content of ∼82 wt%. Moreover, the PAMAM-Cur/Bcl-2 siRNA NPs showed more effective cellular uptake, and higher inhibition of tumor cell proliferation compared to PAMAM-Cur nanoformulation and free Cur, due to the combined effect of co-delivery of Cur and Bcl-2 siRNA. The newly described PAMAM-Cur/Bcl-2 siRNA polyplex NPs could be a promising co-delivery nanovehicle.

Docosahexaenoic acid suppresses migration of triple-negative breast cancer cell through targeting metastasis-related genes and microRNA under normoxic and hypoxic conditions.

There is insufficient evidence with respect to the effect of the standard anticancer therapeutic agents as well as common dietary supplements on the expression of such genes and microRNAs (miRNAs). Therefore, this study was aimed to study the effect of applying linoleic acid (LA) and docosahexaenoic acid (DHA) fatty acids alone or combined with Taxol on the expression of the matrix metalloproteinase (MMP)-9, MMP-2, vimentin, and talin2 genes, tumor-suppressor miR-194 and, onco-miR-106b in triple-negative breast cancer cell line, known as MDA-MB-231. MDA-MB-231 as metastatic breast cancer cell line was cultured and treated using 0.3 µM Taxol, 100 µM DHA, and 50 µM LA for 24 hours, alone or combined with Taxol under the normoxic and hypoxic conditions. Cells were harvested, after RNA extraction and complementary DNA synthesis, analysis of the expression levels of the studied genes and miRNAs was done through the use of the quantitative real-time polymerase chain reaction (qRT-PCR). Wound healing assay and Western blot analysis were also performed for confirmation. The results of qRT-PCR showed that treating the MDA-MB-231 cells with DHA caused an increase in the miR-194 expression and a decrease in the miR-106b expression, leading to the downregulation of the MMP-2 and MMP-9, and vimentin, and upregulation of the talin2 under the normoxic and hypoxic conditions. The results of the wound healing scratch assay revealed that the administration of the DHA and the DHA-Taxol combination caused the repression of cell migration in comparison with the control groups under the normoxic and hypoxic conditions. The results of the Western blot analysis demonstrated that DHA and the DHA-Taxol combination caused an increase in the expression of the talin2 protein rather than the control cells under both normoxic and hypoxic conditions. This study showed that DHA has significant antimetastatic effects against the triple-negative breast cancer cells. DHA could serve as a promising supplementation for suppressing the breast cancer cell migration, especially under the hypoxic condition.

A simple strategy for chemo-photothermal ablation of breast cancer cells by novel smart gold nanoparticles.

Combined therapeutics dependent on the synergistic effect between photothermal therapy (PTT) and chemotherapy have been anticipated to be the next generation of cancer treatment. For this purpose, a novel gold hydrosol was synthesized by a one-pot approach using poly (2-(dimethylamino) ethyl methacrylate-co- N-isopropylacrylamide-co- 2-vinylpyridine) P(DMAEMA-co-NIPAAM-co-VP) terpolymers as a reducing and stabilizing agent. The synthesized gold hydrosol was recoated by a novel carboxylic acid rich poly (N-isopropyl acrylamide-co-maleic anhydride-graft-citric acid) (PNIPAAm-co-PMA-g-CA) copolymer. Then the gold nanoparticles conjugated with Doxorubicin (DOX) and served as a smart photo synthesizer for chemo/photothermal therapy of MCF-7 breast cancer cells. The synthesized nanoparticles had mono-dispersed spherical morphology with a diameter below 30 nm. Our results from cellular uptake indicated that around 100% of the particles were uptake by MCF-7 cells in the first 3 h of exposure time. The temperature of nanocomposites considerably went up to 45 °C with 10 min exposure to near-infrared irradiation. As a striking result, a single round of PTT combined with a sub-therapeutic dose of DOX revealed a synergistic effect with an ability of robust anti-tumor response up to 99.99% (sum of the population of apoptotic and necrotic cells) demonstrated by Annexin-V, cell cycle and DAPI staining techniques. In conclusion, Near-infrared-mediated photothermal conversion exhibited high effectiveness of a combinational chemo-thermotherapy to treat cancer cells.

Photodynamic therapy using zinc phthalocyanine with low dose of diode laser combined with doxorubicin is a synergistic combination therapy for human SK-MEL-3 melanoma cells.

Chemotherapy is a generally used anticancer strategy for melanoma and it may have improved outcomes in combination with other approaches. One such strategy is photodynamic therapy (PDT), where a photosensitizer (PS) generates reactive oxygen species (ROS) after illumination of target cells. Interestingly, in low doses and high doses of light sources, special cellular responses can be induced. Regarding this fact, in this study, the combination of zinc phthalocyanine (ZnPc)-PDT and Doxorubicin (DOX) was applied at low and high dose of diode laser to treat SK-MEL-3 cells. Cytotoxic effects were determined by MTT assay for assessment synergistic effects were estimated by calculation of Combination Index (CI); that synergistic effects were observed in most groups. In low dose of laser irradiation higher synergism effects were observed. Significant changes of ROS were not observed with combinations, but autophagy, subG1 and G2/M phase cell cycle arrest, decreased cell migration ability and apoptosis induction were significantly increased compared to either treatment alone. The expression of caspase-8, -9, -3 and Bcl-2 genes revealed caspase-dependent apoptosis in all groups. Moreover, ZnPc-PDT and chemo-PDT down-regulated the expression of MMP-9 and Vimentin genes that impaired cell migration. In conclusion, it can be suggested that pre-treatment with ZnPc-PDT has high effects to sensitize SK-MEL-3 cells to DOX, in particular with low dose of diode laser.

Photodynamic therapy for cancer: Role of natural products.

Photodynamic therapy (PDT) is a promising modality for the treatment of cancer. PDT involves administering a photosensitizing dye, i.e. photosensitizer, that selectively accumulates in tumors, and shining a light source on the lesion with a wavelength matching the absorption spectrum of the photosensitizer, that exerts a cytotoxic effect after excitation. The reactive oxygen species produced during PDT are responsible for the oxidation of biomolecules, which in turn cause cell death and the necrosis of malignant tissue. PDT is a multi-factorial process that generally involves apoptotic death of the tumor cells, degeneration of the tumor vasculature, stimulation of anti-tumor immune response, and induction of inflammatory reactions in the illuminated lesion. Numerous compounds with photosensitizing activity have been introduced commercially. Although many papers have been published with regard to PDT in the last decade, there has been relatively little focus on natural medicinal plant extracts and compounds derived therefrom. Herbal plants and their extracts are natural substances, and in comparison with synthetic chemicals are considered "green". This review focuses on the different mechanisms of PDT and discusses the role of various plant extracts and natural compounds either alone or in combination for carrying out PDT on different types of cancers.

The interaction between the light source dose and caspase-dependent and -independent apoptosis in human SK-MEL-3 skin cancer cells following photodynamic therapy with zinc phthalocyanine: A comparative study.

The aim of this study is to determine the behavior of relative expression of Bcl-2, caspase-8, caspase-9, and caspase-3 genes of/in SK-MEL-3 cancer cells and explore molecular mechanisms responsible for the apoptosis response during an in vitro photodynamic therapy (PDT) with Zinc Phthalocyanine (ZnPc) using different doses of the light source. In this study, firstly the cytotoxic effects of ZnPc-PDT on SK-MEL-3 cells were evaluated. By irradiating the laser, ZnPc induced a significant amount of apoptosis on SK-MEL-3 cells in three IC50s including 0.064±0.01, 0.043±0.01, and 0.036±0.01µg/mL at the doses of 8, 16, and 24J/cm2, respectively. Moreover, flow cytometry and QRT-PCR experiments were done. The high percentage of apoptotic cells was seen in the early apoptosis stage. The expression of Bcl-2 and caspase-8 genes at all doses of laser experienced an obvious reduction in comparison to the control group. On the other hand, although the expression of caspase-9 and caspase-3 genes remains almost constant at 8J/cm2, but they faced an increment at 16 and 24J/cm2 doses. These data reveal caspase-dependent apoptosis in high and caspase-independent apoptosis in low doses of laser. Based on the results of present work, it can be suggested that the dose of the light source is a key factor in induction of caspase-dependent and caspase-independent apoptosis pathways following PDT.

Urtica dioica extract suppresses miR-21 and metastasis-related genes in breast cancer.

BACKGROUND: Breast cancer has a high prevalence among women worldwide. Tumor invasion and metastasis still remains an open issue that causes most of the therapeutic failures and remains the prime cause of patient mortality. Hence, there is an unmet need to develop the most effective therapeutic approach with the lowest side effects and highest cytotoxicity that will effectively arrest or eradicate metastasis. METHODS: An MTT assay and scratch test were used to assess the cytotoxicity and migration effects of Urtica dioica on the breast cancer cells. The QRT-PCR was used to study the expression levels of miR-21, MMP1, MMP9, MMP13, CXCR4, vimentin, and E-cadherin. RESULTS: The results of gene expression in tumoral groups confirmed the overexpression of miR-21, MMP1, MMP9, MMP13, vimentin, and CXCR4, and the lower expression of E-cadherin compared to control groups (P<0.05). Moreover, the results of the MTT assay show that Urtica dioica significantly inhibited breast cancer cell proliferation. Moreover, findings from the scratch assay exhibited the inhibitory effects of Urtica dioica on the migration of breast cancer cell lines. CONCLUSION: Urtica dioica extract could inhibit cancer cell migration by regulating miR-21, MMP1, MMP9, MMP13, vimentin, CXCR4, and E-Cadherin. Moreover, our findings demonstrated that the extract could decrease miR-21 expression, which substantially lessens the overexpressed MMP1, MMP9, MMP13, vimentin, and CXCR4 and increases E-cadherin in the tumoral group.

Urtica dioica Extract Inhibits Proliferation and Induces Apoptosis and Related Gene Expression of Breast Cancer Cells In Vitro and In Vivo.

INTRODUCTION: Currently, because the prevalence of breast cancer and its consequent mortality has increased enormously in the female population, a number of studies have been designed to identify natural products with special antitumor properties. The main purpose of the present study was to determine the effect of Urtica dioica on triggering apoptosis and diminishing growth, size, and weight of the tumor in an allograft model of BALB/c mice. MATERIALS AND METHODS: In the present study, a BALB/c mouse model of breast cancer (4T1) was used. After emergence of tumor, 2 groups of mice received the extract, 1 group at a dose of 10 mg/kg and 1 group at a dose of 20 mg/kg, by intraperitoneal injection for 28 days. During the test and after removal of the tumor mass, the size and weight of the tumor were measured. To assess the induction of apoptosis in the cancer cells, the TUNEL (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling) assay was performed. The Ki-67 test was used to evaluate tumor proliferation. RESULTS: The results showed that the tumor size in the mice treated with the extract decreased significantly. The weight of the tumor mass in the treated mice after resection was less than that in the control group. The TUNEL assay findings revealed that apoptosis occurred in the treated group. The Ki-67 test findings also demonstrated that administration of the extract suppressed the growth of tumor cells. CONCLUSION: These results suggest that U. dioica extract can decrease the growth of breast tumors and induce apoptosis in tumor cells; thus, it might represent an ideal therapeutic tool for breast cancer.

Suppression of protein tyrosine phosphatase PTPN22 gene induces apoptosis in T-cell leukemia cell line (Jurkat) through the AKT and ERK pathways.

The aim of this study was to investigate the effect of specific PTPN22 small interfering RNAs (siRNAs) on the viability and induction of apoptosis in Jurkat cells and to evaluate apoptosis signaling pathways. In this study, Jurkat cells were transfected with specific PTPN22 siRNA. Relative PTPN22 mRNA expression was measured by Quantitative Real-time PCR. Western blotting was performed to determine the protein levels of PTPN22, AKT, P-AKT, ERK, and P-ERK. The cytotoxic effects of PTPN22 siRNA were determined using the MTT assay. Apoptosis was quantified using TUNEL assay and flow cytometry. Results showed that in Jurkat cells after transfection with PTPN22 siRNA, the expression of PTPN22 in both mRNA and protein levels was effectively reduced. Moreover, siRNA transfection induced apoptosis on the viability of T-cell acute leukemia cells. More importantly, PTPN22 positively regulated the anti-apoptotic AKT kinase, which provides a powerful survival signal to T-ALL cells as well as the suppression of PTPN22 down regulated ERK activity. Our results suggest that the PTPN22 specific siRNA effectively decreases the viability of T-cell acute leukemia cells, induces apoptosis in this cell line, and therefore could be considered as a potent adjuvant in T-ALL therapy.

Regulation of miRNAs by herbal medicine: An emerging field in cancer therapies.

MicroRNAs' expression profiles have recently gained major attention as far as cancer research is concerned. MicroRNAs are able to inhibit target gene expression via binding to the 3' UTR of target mRNA, resulting in target mRNA cleavage or translation inhibition. MicroRNAs play significant parts in a myriad of biological processes; studies have proven, on the other hand, that aberrant microRNA expression is, more often than not, associated with the growth and progression of cancers. MicroRNAs could act as oncogenes (oncomir) or tumor suppressors and can also be utilized as biomarkers for diagnosis, prognosis, and cancer therapy. Recent studies have shown that such herbal extracts as Shikonin, Sinomenium acutum, curcumin, Olea europaea, ginseng, and Coptidis Rhizoma could alter microRNA expression profiles through inhibiting cancer cell development, activating the apoptosis pathway, or increasing the efficacy of conventional cancer therapeutics. Such findings patently suggest that the novel specific targeting of microRNAs by herbal extracts could complete the restriction of tumors by killing the cancerous cells so as to recover survival results in patients diagnosed with malignancies. In this review, we summarized the current research about microRNA biogenesis, microRNAs in cancer, herbal compounds with anti-cancer effects and novel strategies for employing herbal extracts in order to target microRNAs for a better treatment of patients diagnosed with cancer.

Growth inhibitory effect of Scrophularia oxysepala extract on mouse mammary carcinoma 4T1 cells in vitro and in vivo systems.

INTRODUCTION: Medical plants have been intensively studied as a source of antitumor compounds. In the present study, we determine the effect of Scrophularia oxysepala on triggering apoptosis and diminishing growth, size and weight of the tumor in the allograft model of Balb/c mice. MATERIAL & METHODS: The cytotoxic effects of Scrophularia oxysepala extract on 4T1 cells were studied using MTT (3-[4,5-dimethyl-2-thiazolyl]-2, 5 diphenyl tetrazolium bromide) assay and Trypan blue staining. DNA fragmentation assay was done for apoptosis detection. After the establishment of tumor in Balb/c mice, two groups of mice were received the extract at two doses of 50 and 100mg/kg respectively using intraperitoneal injection once every two days for 28 days. In order to assess the induction of apoptosis in cancer cells, the TUNEL assay was carried out in tumoral tissues. Moreover, the Ki67 test was used to evaluate tumor proliferation. RESULTS: According to the findings, the Scrophularia oxysepala extract inhibited cell growth. In vivo results showed that tumor size in mice treated with the extract was significantly reduced. The weight of tumor mass in treated mice after resection was less than the control group. According to the TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay results, the herbal extract induced apoptosis in tumoral cells. Ki67 test also demonstrated that administration of the extract suppressed the growth of tumor cells. CONCLUSION: Our data well approved the anti-proliferative effect of Scrophularia oxysepala extract, and clearly showed that, the plant extract can decrease the growth of breast cancer cells in tumor mass. Thus it may represent an ideal therapeutic tool for breast cancer.

Anacyclus Pyrethrum Extract Exerts Anticancer Activities on the Human Colorectal Cancer Cell Line (HCT) by Targeting Apoptosis, Metastasis and Cell Cycle Arrest.

INTRODUCTION: Colorectal cancer is the second leading cause of cancer mortality in the USA. There are a number of medicinal plants triggering apoptosis response in cancer cells, thus have a therapeutic potential. On the other hand, due to traditional uses and availability of Anacyclus pyrethrum extract, we decided to evaluate the efficacy of this medicinal herb on human colorectal cancer cell line (HCT). MATERIALS AND METHODS: In the present study, the cytotoxic effects of Anacyclus pyrethrum extract were assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and trypan blue viability dye. Then, flow cytometry assay was exploited to measure cell death and apoptosis stage. The scratch test was exploited to assess the effect of Anacyclus pyrethrum on the migration of cancer cells. The expression levels of Caspase 3, Bcl-2, MMP1, and Vimentin genes were quantified by real-time PCR. Finally, cell cycle was analyzed by flow cytometry. RESULTS: MTT assay showed that Anacyclus pyrethrum extract significantly inhibited the cell growth. According to the flow cytometry assay result, the herbal extract was able to induce apoptosis in colorectal cancer cells. Our findings also demonstrated that the plant extract substantially increases the caspase 3 mRNA expression, while decreases Bcl-2, MMP1, and Vimentin. Cell cycle arrest occurred in G1 stage, due to the results of flow cytometry. CONCLUSION: These results indicate that Anacyclus pyrethrum extract can successfully induce apoptosis in HCT cells. Therefore, it could be used as a novel therapeutic candidate for colorectal cancer treatment.

The Urtica dioica extract enhances sensitivity of paclitaxel drug to MDA-MB-468 breast cancer cells.

INTRODUCTION: Due to the chemo resistant nature of cancer cells and adverse effects of current therapies, researchers are looking for the most efficient therapeutic approach which has the lowest side effects and the highest toxicity on cancer cells. The aim of the present study was to investigate the synergic effect of Urtica dioica extract in combination with paclitaxel on cell death and invasion of human breast cancer MDA-MB-468 cell line. MATERIALS AND METHODS: To determine the cytotoxic effects of Urtica dioica extract with paclitaxel, MTT assay was performed. The scratch test was exploited to assess the effects of Urtica dioica, Paclitaxel alone and combination on migration of cancer cells. The expression levels of snail-1, ZEB1, ZEB2, twist, Cdc2, cyclin B1 and Wee1 genes were quantified using qRT-PCR and western blot performed for snail-1expression. The effects of plant extract, Paclitaxel alone and combination on different phases of cell cycle was analyzed using flow cytometry. RESULTS: Results of MTT assay showed that Urtica dioica significantly destroyed cancer cells. Interestingly, Concurrent use of Urtica dioica extract with paclitaxel resulted in decreased IC50 dose of paclitaxel. Moreover, findings of scratch assay exhibited the inhibitory effects of Urtica dioica, Paclitaxel alone and combination on migration of MDA-MB-468 cell line. Our findings also demonstrated that the extract substantially decreased the Snail-1 and related gene expression. Ultimately, Cell cycle arrest occurred at G2/M phase post-treatment by deregulating Cdc2 and wee1. CONCLUSIONS: Our results demonstrated that the dichloromethane extract of Urtica dioica inhibit cell growth and migration. Also, Urtica dioica extract substantially increased sensitivity of breast cancer cells to paclitaxel. Therefore, it can be used as a potential candidate for treatment of breast cancer with paclitaxel.

The Herbal Medicine Utrica Dioica Inhibits Proliferation of Colorectal Cancer Cell Line by Inducing Apoptosis and Arrest at the G2/M Phase.

BACKGROUND: One of the major causes of cancer death internationally and the third most prevalent cancer in the world has been diagnosed with colorectal cancer. Although current routine treatments of cancer have been successful in some extent, mortality caused by adverse effects of these strategies is still raising. Medicinal plants are potential sources of anticancer compounds and can be exploited as a powerful complementary tool. This study aimed to investigate the cytotoxic effects of nettle extract on mouse colorectal cancer cells, HCT. MATERIALS AND METHODS: In the present study, to evaluate the cytotoxicity of nettle extract, MTT assay and trypan blue were performed. Subsequently, DNA fragmentation and TUNEL test was carried out for determination of apoptosis. Real-time PCR test was used to quantify the expression of Caspase-3, Caspase-9, and Bcl-2 which is involved in apoptosis regulation. Finally, cell cycle analysis was conducted by using flow cytometry. RESULTS: The results of MTT assay showed that the dichloromethane extract of U. dioica extract significantly destroyed cancer cells HCT-116. DNA fragmentation and TUNEL test demonstrated that Utrica extract elicited apoptotic response in the cancer cells. The messenger RNA (mRNA) expression levels of Caspase-3 and Caspase-9 markedly increased, while the Bcl-2 gene was conversely downregulated. Findings of flow cytometry confirmed that cell cycle arrest has occurred at the G2 phase. CONCLUSION: Taken together, our experiment showed that subjecting HCT-116 cells to dichloromethane extract of nettle (U. dioica), increases turnover of these cells. Thus, it may be a useful agent in the treatment of colorectal cancer.

Effects of dietary tannic acid and vaccination on the course of coccidiosis in experimentally challenged broiler chicken.

An experiment was carried out to assess the influence of tannic acid (TA) on integrity of the intestine in broiler chicks vaccinated against coccidiosis and challenged with the disease. In a 2 × 2 factorial design, the trial had five groups of 10 chickens each, including positive (group 2) and negative (group 1) controls. The chickens were kept on wood shavings and fed a commercial maize and soybean-based starter-grower diet. From day 1, groups 3 and 5 received TA (10 g kg(-1)) in their diet. On day 4, birds of groups 4 and 5 were vaccinated orally against coccidiosis with anti-coccidial vaccine, Livacox T™. Each dose of the vaccine contained 300-500 sporulated oocysts of each of Eimeria acervulina, Eimeria maxima and Eimeria tenella. On day 18, all experimental groups except for the negative (group 1) were challenged with 10-fold dose of Livacox T™ to produce a mild coccidiosis infection. Faecal samples of individual birds were collected on day 23, and the number of faecal oocysts was determined. d-Xylose absorption test was also carried out on all birds on day 23. Immediately after d-xylose absorption test, all birds were killed humanely and the intestinal tract was removed, weighed and examined for gross lesions. Results showed that negative (group 1) and positive controls (group 2) had the highest and lowest levels of plasma d-xylose post-ingestion of the substrate, respectively. Vaccination and/or feeding TA raised the level of plasma d-xylose in infected birds, although this was not significant for TA-fed birds. Vaccination reduced but TA increased the total number of oocysts per gram of faeces. Birds of groups 2-5 had distinct intestinal lesions when compared with group 1. However, vaccination prevented intestinal lesions. Relative weights of intestinal parts were the lowest in group 1 and the highest in group 2. Vaccination but not TA reduced the relative weights of intestinal parts in infected birds. It was concluded that dietary tannins may reduce the efficacy of anticoccidial vaccines and alter the proper development of immunity against the disease.