A 10% Tomato Diet Selectively Reduces Radiation-Induced Damage in TRAMP Mice.

BACKGROUND: Tomatoes contain carotenoids that have the potential to alter the effects of external beam radiation therapy (EBRT). OBJECTIVES: We hypothesized that dietary lyophilized tomato paste (TP) would reduce apoptosis within carotenoid-containing nonneoplastic tissues in EBRT-treated TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) mice. METHODS: Male TRAMP mice (n = 73) were provided an AIN-93G diet or a modified AIN-93G diet containing 10% TP (wt:wt) at 4 wk of age. Prostate tumor growth was monitored by ultrasound. The caudal half of the mouse was irradiated with 7.5 Gy (Rad) or 0 Gy (sham) at 24 wk of age or after the tumor volume exceeded 1000 mm3 with a Cobalt-60 source. Mice were euthanized 24 h postradiation. Carotenoids and α-tocopherol were measured by HPLC and compared by a t test. Tissues were assessed for radiation-induced changes (hematoxylin and eosin) and apoptosis [cleaved caspase-3 (CC3)] and compared by Kruskal-Wallis test or Freedman-Lane's permutation test. RESULTS: Serum concentrations of lycopene (52% lower), phytoene (26% lower), and α-tocopherol (22% lower) were decreased in TP-fed irradiated mice (TP-Rad) compared with TP-fed sham mice (P < 0.05). CC3 scores increased within the prostate tumor with radiation treatments (P < 0.05), but were not affected by tomato consumption. In nonneoplastic tissues, TP-Rad had a lower percentage of CC3-positive cells within the cranial (67% lower) and caudal (75% lower) duodenum than irradiated mice on the control diet (Rad) (P < 0.005). Likewise, CC3 scores within the dorsolateral prostate of TP-Rad trended toward lower scores than for Rad (P = 0.07). CONCLUSIONS: TP selectively reduces radiation-induced apoptosis in extratumoral tissues without decreasing radiation-induced apoptosis within the prostate tumor in TRAMP mice. Additional studies are needed to confirm and expand upon these findings.

Dietary Tomato or Lycopene Do Not Reduce Castration-Resistant Prostate Cancer Progression in a Murine Model.

BACKGROUND: Dietary tomato products or lycopene protect against prostate carcinogenesis, but their impact on the emergence of castration-resistant prostate cancer (CRPC) is unknown. OBJECTIVE: We hypothesized that tomato or lycopene products would reduce the emergence of CRPC. METHODS: Transgenic adenocarcinoma of the mouse prostate (TRAMP) mice were castrated at 12-13 wk and the emergence of CRPC was monitored by ultrasound in each study. In Study 1, TRAMP mice (n = 80) were weaned onto an AIN-93G-based control diet (Con-L, n = 28), a 10% tomato powder diet (TP-L, 10% lyophilized w/w, n = 26), or a control diet followed by a tomato powder diet after castration (TP-Int1, n = 26). In Study 2, TRAMP mice (n = 85) were randomized onto a control diet with placebo beadlets (Con-Int, n = 29), a tomato diet with placebo beadlets (TP-Int2, n = 29), or a control diet with lycopene beadlets (Lyc-Int, n = 27) following castration (aged 12 wk). Tumor incidence and growth were monitored by ultrasound beginning at an age of 10 wk. Mice were euthanized 4 wk after tumor detection or aged 30 wk if no tumor was detected. Tissue weights were compared by ANOVA followed by Dunnett's test. Tumor volumes were compared using generalized linear mixed model regression. RESULTS: Ultrasound estimates for the in vivo tumor volume were strongly correlated with tumor weight at necropsy (R2 = 0.75 and 0.94, P <0.001 for both Studies 1 and 2, respectively). Dietary treatments after castration did not significantly impact cancer incidence, time to tumor detection, or final tumor weight. CONCLUSIONS: In contrast to studies of de novo carcinogenesis in multiple preclinical models, tomato components had no significant impact on the emergence of CRPC in the TRAMP model. It is possible that specific mutant subclones of prostate cancer may continue to show some antiproliferative response to tomato components, but further studies are needed to confirm this.

Quantitative Ultrasound and the Pancreas: Demonstration of Early Detection Capability.

OBJECTIVES: To show that quantitative ultrasound biomarkers attenuation (AC) and backscatter (BSC) coefficients are effective tools to detect early changes in acute pancreatitis, using a cerulein-induced pancreatitis rat model. METHODS: Sprague-Dawley rats (n = 68) were divided into 8 groups: uninjected cage controls, saline-injected controls, and cerulein-injected rats euthanized at 2, 4, 15, 24, 48, and 60 hours after injection. Pancreatic AC and BSC (25-55 MHz) were estimated in vivo (Vevo 2100, VisualSonics, Toronto, CA) and ex vivo (40-MHz transducer). The pancreas of each rat was evaluated histopathologically. RESULTS: Changes in both in vivo and ex vivo AC and BSC relative to controls reflected temporal histomorphologic changes. Overall, there were decreased AC and BSC at early time points and then rebound toward control values over time. Maximal in vivo AC and BSC decreases occurred at 2 hours after cerulein injection. Attenuation coefficient changes corresponded well with early pancreatic edema and acinar cell vacuolation, with rebound as edema decreased, autophagy/cellular death occurred, and histiocytic infiltrates and fibrosis manifested. Backscatter coefficient decreased early but rebounded as autophagy and apoptosis increased, only to fall as acinar atrophy peaked, and fibrosis and histiocytic infiltration increased. CONCLUSIONS: Cerulein-induced pancreatitis is an excellent model for studying ultrasonic AC and BSC biomarkers during the early stages of acute pancreatitits, reflecting microscopic structural changes. Edema followed by cell shrinkage and apoptosis, then histiocytic infiltration and fibrosis, has certain similarities with the morphologies of some forms of pancreatic carcinoma. This suggests that quantitative ultrasound may be very useful for early detection of disease onset or response to therapy for not only acute pancreatitis but also pancreatic cancer.

Exercise and gut immune function: evidence of alterations in colon immune cell homeostasis and microbiome characteristics with exercise training.

There is robust evidence that habitual physical activity is anti-inflammatory and protective against developing chronic inflammatory disease. Much less is known about the effects of habitual moderate exercise in the gut, the compartment that has the greatest immunological responsibility and interactions with the intestinal microbiota. The link between the two has become evident, as recent studies have linked intestinal dysbiosis, or the disproportionate balance of beneficial to pathogenic microbes, with increased inflammatory disease susceptibility. Limited animal and human research findings imply that exercise may have a beneficial role in preventing and ameliorating such diseases by having an effect on gut immune function and, recently, microbiome characteristics. Emerging data from our laboratory show that different forms of exercise training differentially impact the severity of intestinal inflammation during an inflammatory insult (for example, ulcerative colitis) and may be jointly related to gut immune cell homeostasis and microbiota-immune interactions. The evidence we review and present will provide data in support of rigorous investigations concerning the effects of habitual exercise on gut health and disease.

Mice lacking ß-carotene-15,15'-dioxygenase exhibit reduced serum testosterone, prostatic androgen receptor signaling, and prostatic cellular proliferation.

ß-Carotene-15,15'-dioxygenase (BCO1) cleaves dietary carotenoids at the central 15,15' double bond, most notably acting on ß-carotene to yield retinal. However, Bco1 disruption also impacts diverse physiological end points independent of dietary carotenoid feeding, including expression of genes controlling androgen metabolism. Using the Bco1-/- mouse model, we sought to probe the effects of Bco1 disruption on testicular steroidogenesis, prostatic androgen signaling, and prostatic proliferation. Male wild-type (WT) and Bco1-/- mice were raised on carotenoid-free AIN-93G diets before euthanasia between 10 and 14 wk of age. Weights of the prostate and seminal vesicles were significantly lower in Bco1-/- than in WT mice (-18% and -29%, respectively). Serum testosterone levels in Bco1-/- mice were significantly reduced by 73%. Bco1 disruption significantly reduced Leydig cell number and decreased testicular mRNA expression of Hsd17b3, suggesting inhibition of testicular testosterone synthesis. Immunofluorescent staining of the androgen receptor (AR) in the dorsolateral prostate lobes of Bco1-/- mice revealed a decrease in AR nuclear localization. Analysis of prostatic morphology suggested decreases in gland size and secretion. These findings were supported by reduced expression of the proliferation marker Ki-67 in Bco1-/- prostates. Expression analysis of 200 prostate cancer- and androgen-related genes suggested that Bco1 loss significantly disrupted prostatic androgen receptor signaling, cell cycle progression, and proliferation. This is the first demonstration that Bco1 disruption lowers murine circulating testosterone levels and thereby reduces prostatic androgen receptor signaling and prostatic cellular proliferation, further supporting the role of this protein in processes more diverse than carotenoid cleavage.

Dietary Broccoli Lessens Development of Fatty Liver and Liver Cancer in Mice Given Diethylnitrosamine and Fed a Western or Control Diet.

BACKGROUND: The high-fat and high-sugar Westernized diet that is popular worldwide is associated with increased body fat accumulation, which has been related to the development of nonalcoholic fatty liver disease (NAFLD). Without treatment, NAFLD may progress to hepatocellular carcinoma (HCC), a cancer with a high mortality rate. The consumption of broccoli in the United States has greatly increased in the last 2 decades. Epidemiologic studies show that incorporating brassica vegetables into the daily diet lowers the risk of several cancers, although, to our knowledge, this is the first study to evaluate HCC prevention through dietary broccoli. OBJECTIVE: We aimed to determine the impact of dietary broccoli on hepatic lipid metabolism and the progression of NAFLD to HCC. Our hypothesis was that broccoli decreases both hepatic lipidosis and the development of HCC in a mouse model of Western diet-enhanced liver cancer. METHODS: Adult 5-wk-old male B6C3F1 mice received a control diet (AIN-93M) or a Western diet (high in lard and sucrose, 19% and 31%, wt:wt, respectively), with or without freeze-dried broccoli (10%, wt:wt). Starting the following week, mice were treated once per week with diethylnitrosamine (DEN; 45 mg/kg body weight intraperitoneally at ages 6, 7, 8, 10, 11, and 12 wk). Hepatic gene expression, lipidosis, and tumor outcomes were analyzed 6 mo later, when mice were 9 mo old. RESULTS: Mice receiving broccoli exhibited lower hepatic triglycerides (P < 0.001) and NAFLD scores (P < 0.0001), decreased plasma alanine aminotransferase (P < 0.0001), suppressed activation of hepatic CD68(+) macrophages (P < 0.0001), and slowed initiation and progression of hepatic neoplasm. Hepatic Cd36 was downregulated by broccoli feeding (P = 0.006), whereas microsomal triglyceride transfer protein was upregulated (P = 0.045), supporting the finding that dietary broccoli decreased hepatic triglycerides. CONCLUSION: Long-term consumption of whole broccoli countered both NAFLD development enhanced by a Western diet and hepatic tumorigenesis induced by DEN in male B6C3F1 mice.

Nasal Tumorigenesis in B6C3F1 Mice Following Intraperitoneal Diethylnitrosamine.

Diethylnitrosamine (DEN) is a chemical broadly used in animal models as a hepatocarcinogen, reported to also cause pulmonary neoplasms in mice. The original objective was to evaluate the impact of a Western diet with or without 10% broccoli on DEN-induced on liver cancer. We administered DEN (45 mg/kg) intraperitoneally to young adult male B6C3F1 mice by 6 weekly injections and evaluated liver cancer 6 months after the DEN treatments. Here, we report unexpected primary tumorigenesis in nasal epithelium, independent of dietary treatment. More than 50% of DEN-treated B6C3F1 mice developed nasal neoplasm-related lesions, not reported previously in the literature. Only one of these neoplasms was visible externally prior to postmortem examination. Intraperitoneal DEN treatment used as a model for liver cancer can have a carcinogenic effect on the nasal epithelium in B6C3F1 mice, which should be carefully monitored in future liver cancer studies.

Moderately Fermentable Potato Fiber Attenuates Signs and Inflammation Associated with Experimental Colitis in Mice.

BACKGROUND: Dietary fiber intake leading to short-chain fatty acid (SCFA) production could be a strategy to combat intermittent bouts of inflammation during ulcerative colitis. OBJECTIVE: Our objective was to evaluate dietary potato fiber (PF) in attenuating inflammation using a dextran sodium sulfate (DSS)-induced colitis mouse model. We hypothesized that PF would show anti-inflammatory effects compared with cellulose due in part to SCFA production. METHODS: Male C57Bl/6J mice were fed diets containing either 8% cellulose or 14.5% PF for a 22-d feeding study. Starting on study day 14, mice were provided either distilled water (control) or 2% (wt:vol) DSS in drinking water for 5 d (cellulose+control, n = 17; PF+control, n = 16; cellulose+DSS, n = 17; and PF+DSS, n = 16). Body weights and food and water intakes were collected daily from day 14 through day 22. Distal colon tissue was analyzed for histologic outcomes and changes in gene expression, and cecal contents were analyzed for SCFA concentrations. Data were analyzed by ANOVA, with repeated measures applied where necessary. RESULTS: At day 5 post-DSS induction, cellulose+DSS mice exhibited a 2% reduction (P < 0.05) in body weight compared with PF+DSS and PF+ and cellulose+control mice. PF+DSS mice had greater (P < 0.05) cecal butyrate concentrations [24.5 µmol/g dry matter (DM)] than did cellulose+DSS mice (4.93 µmol/g DM). Mice fed PF+DSS had lower (P < 0.05) infiltration of leukocytes in the distal colon than did mice fed cellulose+DSS (mean histology scores of 1.22 and 2.30, respectively). Furthermore, mice fed cellulose+DSS exhibited 1.42, 11.5, 8.48, and 35.5 times greater (P < 0.05) colon mRNA expression of tumor necrosis factor α (Tnfa) and interleukin (Il) 1b, Il6, and Il17a, respectively, and 7.10 times greater (P < 0.05) expression of C-X-C motif ligand 1 (Cxc1) compared with mice fed PF+DSS. CONCLUSIONS: These results suggest that PF fed to mice before and during DSS colitis attenuates inflammation, potentially through SCFA production; however, future studies are needed to understand the role of dietary fiber intake and immune activation.

Gut microbiome responds to alteration in female sex hormone status and exacerbates metabolic dysfunction.

Women are at significantly greater risk of metabolic dysfunction after menopause, which subsequently leads to numerous chronic illnesses. The gut microbiome is associated with obesity and metabolic dysfunction, but its interaction with female sex hormone status and the resulting impact on host metabolism remains unclear. Herein, we characterized inflammatory and metabolic phenotypes as well as the gut microbiome associated with ovariectomy and high-fat diet feeding, compared to gonadal intact and low-fat diet controls. We then performed fecal microbiota transplantation (FMT) using gnotobiotic mice to identify the impact of ovariectomy-associated gut microbiome on inflammatory and metabolic outcomes. We demonstrated that ovariectomy led to greater gastrointestinal permeability and inflammation of the gut and metabolic organs, and that a high-fat diet exacerbated these phenotypes. Ovariectomy also led to alteration of the gut microbiome, including greater fecal ß-glucuronidase activity. However, differential changes in the gut microbiome only occurred when fed a low-fat diet, not the high-fat diet. Gnotobiotic mice that received the gut microbiome from ovariectomized mice fed the low-fat diet had greater weight gain and hepatic gene expression related to metabolic dysfunction and inflammation than those that received intact sham control-associated microbiome. These results indicate that the gut microbiome responds to alterations in female sex hormone status and contributes to metabolic dysfunction. Identifying and developing gut microbiome-targeted modulators to regulate sex hormones may be useful therapeutically in remediating menopause-related diseases.

Forced treadmill exercise training exacerbates inflammation and causes mortality while voluntary wheel training is protective in a mouse model of colitis.

The purpose of this study was to examine whether exercise training reduced inflammation and symptomology in a mouse model of colitis. We hypothesized that moderate forced treadmill running (FTR) or voluntary wheel running (VWR) would reduce colitis symptoms and colon inflammation in response to dextran sodium sulfate (DSS). Male C57Bl/6J mice were randomized to sedentary, moderate intensity FTR (8-12 m/min, 40 min, 6 weeks, 5x/week), or VWR (30 days access to wheels). DSS was given at 2% (w/v) in drinking water over 5 days. Mice discontinued exercise 24 h prior to and during DSS treatment. Colons were harvested on Days 6, 8 and 12 in FTR and Day 8 post-DSS in VWR experiments. Contrary to our hypothesis, we found that moderate FTR exacerbated colitis symptomology and inflammation as measured by significant (p<0.05) increases in diarrhea and IL-6, IL-1ß, IL-17 colon gene expression. We also observed higher mortality (3/10 died vs. 0/10, p=0.07) in the FTR/DSS group. In contrast, VWR alleviated colitis symptoms and reduced inflammatory gene expression in the colons of DSS-treated mice (p<0.05). While DSS treatment reduced food/fluid intake and body weight, there was a tendency for FTR to exacerbate, and for VWR to attenuate, this effect. FTR (in the absence of DSS) increased gene expression of the chemokine and antibacterial protein CCL6 suggesting that FTR altered gut homeostasis that may be related to the exaggerated response to DSS. In conclusion, we found that FTR exacerbated, whereas VWR attenuated, symptoms and inflammation in response to DSS.

Nature via nurture: effect of diet on health, obesity, and safety assessment.

Food is not only vital for the health and well-being of any living being, but it is a potential source of harmful chemicals, both natural and man-made. Further complicating this is the fact that most nutrients themselves are potentially toxic when consumed in excess. Deficiencies in some of these same nutrients may cause effects that resemble toxicosis or enhance the toxic potential of other nutrients or exogenous chemicals and drugs. This review discusses some of the nutritional and metabolic mechanisms involved and the implications of excess and deficiency in macronutrients and micronutrients in toxicologic pathology. In addition, we review the adverse effects of ad libitum (AL) overfeeding on metabolic, endocrine, renal, and cardiac diseases, and many cancers and the healthful effects of moderate dietary restriction (DR) in modulating obesity and controlling spontaneous and induced diseases of laboratory animals used in toxicology and carcinogenicity studies for human safety assessment.

Impact of administration route on nanocarrier biodistribution in a murine colitis model.

The incidence of inflammatory bowel disease (IBD) is increasing worldwide. Although current diagnostic and disease monitoring tests for IBD sensitively detect gut inflammation, they lack the molecular and cellular specificity of positron emission tomography (PET). In this proof-of-concept study, we use a radiolabeled macrophage-targeted nanocarrier probe (64Cu-NOTA-D500) administered by oral, enema, and intraperitoneal routes to evaluate the delivery route dependence of biodistribution across healthy and diseased tissues in a murine model of dextran sodium sulfate (DSS)-induced colitis. High inter-subject variability of probe uptake in intestinal tissue was reduced by normalization to uptake in liver or total intestines. Differences in normalized uptake between healthy and DSS colitis animal intestines were highest for oral and IP routes. Differences in absolute liver uptake reflected a possible secondary diagnostic metric of IBD pathology. These results should inform the preclinical development of inflammation-targeted contrast agents for IBD and related gut disorders to improve diagnostic accuracy.

Dietary tomato inhibits angiogenesis in TRAMP prostate cancer but is not protective with a Western-style diet in this pilot study.

Prostate cancer (PCa) remains the second most diagnosed cancer worldwide. Higher body weight is associated with chronic inflammation, increased angiogenesis, and treatment-resistant tumor phenotypes. Dietary tomato reduces PCa risk, which may be due to tomato inhibition of angiogenesis and disruption of androgen signaling. This pilot study investigated the interplay between tomato powder (TP), incorporated into control (CON) and obesogenic (OB) diets, and PCa tumor growth and blood perfusion over time in a transgenic model of PCa (TRAMP). Ultrasound microvessel imaging (UMI) results showed good agreement with gold-standard immunohistochemistry quantification of endothelial cell density, indicating that this technique can be applied to non-invasively monitor tumor blood perfusion in vivo. Greater body weight was positively associated with tumor growth. We also found that TP significantly inhibited prostate tumor angiogenesis but that this inhibition differentially affected measured outcomes depending on CON or OB diets. TP led to reduced tumor growth, intratumoral inflammation, and intratumoral androgen-regulated gene expression (srd5a1, srd5a2) when incorporated with the CON diet but greater tumor growth and intratumoral gene expression when incorporated with the OB diet. Results from this study show that protective benefits from dietary tomato are lost, or may become deleterious, when combined with a Western-style diet.

Nanocarriers targeting adipose macrophages increase glucocorticoid anti-inflammatory potency to ameliorate metabolic dysfunction.

Obesity is associated with systemic inflammation due to macrophage accumulation in adipose tissue (AT). AT macrophages are, therefore, a target for therapeutics to modulate inflammation and prevent comorbidities. Because inflammatory processes have pleiotropic effects throughout the body and are intertwined with metabolic axes, systemic anti-inflammatory therapies are often harmful. We report that targeting AT macrophages using dextran nanocarriers radically alters the pharmacology of anti-inflammatory glucocorticoids, uncoupling the metabolic axis in obese mice. Following a single treatment, expression of inflammatory mediators and markers of inflammatory macrophages decreased with a nearly 20-fold higher potency compared with free drug. As a result, long-term treatment resulted in potent fat mobilization, AT reduction, weight loss, improved glucose tolerance, and altered AT gene expression profiles that led to elevated liver stress. Two weeks after treatment ceased, gene expression of inflammatory mediators in AT remained lower than obese controls, while gene expression related to metabolic function improved. These data demonstrate that nanocarriers show potential for amelioration of obesity-related AT inflammation and metabolic dysfunction, highlighting an important opportunity for nanomedicine to impact chronic metabolic disorders with complex and poorly understood etiology.

Dietary fructose induces a wide range of genes with distinct shift in carbohydrate and lipid metabolism in fed and fasted rat liver.

Dietary fructose has been suspected to contribute to development of metabolic syndrome. However, underlying mechanisms of fructose effects are not well characterized. We investigated metabolic outcomes and hepatic expression of key regulatory genes upon fructose feeding under well defined conditions. Rats were fed a 63% (w/w) glucose or fructose diet for 4 h/day for 2 weeks, and were killed after feeding or 24-hour fasting. Liver glycogen was higher in the fructose-fed rats, indicating robust conversion of fructose to glycogen through gluconeogenesis despite simultaneous induction of genes for de novo lipogenesis and increased liver triglycerides. Fructose feeding increased mRNA of previously unidentified genes involved in macronutrient metabolism including fructokinase, aldolase B, phosphofructokinase-1, fructose-1,6-bisphosphatase and carbohydrate response element binding protein (ChREBP). Activity of glucose-6-phosphate dehydrogenase, a key enzyme for ChREBP activation, remained elevated in both fed and fasted fructose groups. In the fasted liver, the fructose group showed lower non-esterified fatty acids, triglycerides and microsomal triglyceride transfer protein mRNA, suggesting low VLDL synthesis even though plasma VLDL triglycerides were higher. In conclusion, fructose feeding induced a broader range of genes than previously identified with simultaneous increase in glycogen and triglycerides in liver. The induction may be in part mediated by ChREBP.

Low fat but not soy protein isolate was an effective intervention to reduce nonalcoholic fatty liver disease progression in C57BL/6J mice: monitored by a novel quantitative ultrasound (QUS) method.

Untreated nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) lead to irreversible liver damage. We hypothesized that a low-fat diet (LFD) or a high-fat diet (HFD) with soy protein isolate (SPI) would be an effective intervention to halt or reverse NAFLD progression. To test these hypotheses, we conducted 2 studies. In the first study, we fed an HFD to 7-week-old C57BL/6J mice to induce NAFLD compared to an LFD (control). Hepatic steatosis was monitored by quantitative ultrasound (QUS) scans (in vivo and ex vivo). Animals were euthanized after 0, 2, 4, and 6 weeks of feeding. In the second study, 7-week-old mice were randomized onto an LFD or HFD with SPI intervention after 4 weeks of feeding HFD. Animals from each group were scanned with QUS and euthanized after 4, 9, and 12 weeks of feeding. Animals fed the HFD developed NAFLD (100%) and NASH (80%) characterized by increased liver weight, lipid accumulation, and histological scores for inflammation by 4 weeks in the first study. In the second study, the LFD ameliorated this NAFLD phenotype after 5 weeks of feeding; however, the SPI intervention failed to significantly attenuate NAFLD. QUS parameters were significantly increased with the HFDs (P < .05) and steatosis grade (P < .05) and were positively correlated with hepatic lipid concentrations. In conclusion, dietary modification may be effective at reversing NAFLD and NASH at early stages. Furthermore, QUS may become a valuable tool to track hepatic steatosis. Additional studies are needed to further evaluate the effectiveness of these interventions.

Mucosal distribution of eosinophilic granulocytes within the gastrointestinal tract of horses.

OBJECTIVES: To establish reference values for the range of the number of eosinophils found in equine gastrointestinal mucosa and to describe the distribution of this cell within the equine gastrointestinal mucosa. SAMPLE POPULATION: Gastrointestinal mucosal specimens from 14 adult horses euthanatized for reasons other than gastrointestinal disease. PROCEDURES: Gastrointestinal mucosal specimens were collected and grouped according to their anatomic regions. For histologic examination slides were stained with Luna's eosinophil stain to determine eosinophil accumulation and distribution. The mucosa was divided into 5 sections for each anatomic location, and the percentage of eosinophils in each of the 5 sections relative to the total eosinophil count in all sections was determined. Additionally, the number of eosinophils per square millimeter of mucosa was calculated as a measure of the degree of eosinophil accumulation. RESULTS: Lowest numbers of eosinophils were found in the stomach, and numbers increased from there to the cecum, then decreased from the ascending colon (right ventral colon, left ventral colon, pelvic flexure, left dorsal colon, and right dorsal colon) to small colon. In all gastrointestinal sections, most eosinophils were located near the muscularis mucosae and were rarely found near or on the luminal surface of the mucosa. CONCLUSIONS AND CLINICAL RELEVANCE: The distribution of eosinophils in the gastrointestinal tract of horses followed a pattern within the mucosa and between different sections of the gastrointestinal tract. The derived reference values and distribution data could be used to detect changes in eosinophil response in the equine gastrointestinal mucosa caused by diseases states.

Lightly Cooked Broccoli Is as Effective as Raw Broccoli in Mitigating Dextran Sulfate Sodium-Induced Colitis in Mice.

Dietary broccoli is anti-inflammatory. Past studies have typically investigated raw broccoli, even though most consumers prefer cooked broccoli, where the plant myrosinase is inactivated by heat, resulting in failure of formation of the anti-inflammatory bioactive compound sulforaphane (SF). This study compareed efficacy of lightly cooked broccoli (CB) containing greatly diminished myrosinase activity, with raw broccoli (RB), in mitigating colitis in dextran sulfate sodium (DSS)-treated mice. Male C57BL/6 mice were fed for two weeks on a 10% RB, 10% CB or control diet, all based on the AIN-93M diet. Half (n = 9) of each group received drinking water, half received 2.5% DSS in water for one week, starting from Day 7 of the diet. Even with far less plant myrosinase activity, CB was essentially as effective as RB in lessening damage by DSS, evidenced by decreased disease activity index, attenuated colon length shrinkage, less endotoxin (lipopolysaccharide) leakage into blood, and less severe colon lesions as assessed by histopathology. mRNA expression of pro-inflammatory cytokines indicated that broccoli anti-inflammatory action may be through inhibition of the IL-6 trans-signaling pathway, as evidenced by reversal of the DSS-increased expression of IL-6, CCR2 and vascular cell adhesion molecule 1 (VCAM-1).

In vitro cyclooxygenase-2 protein expression and enzymatic activity in neoplastic cells.

BACKGROUND: Cyclooxygenase-2 (COX-2) and its principle enzymatic metabolite, prostaglandin E2 (PGE2), are implicated in cancer progression. Based upon immunohistochemical (IHC) evidence that several tumor types in animals overexpress COX-2 protein, COX-2 inhibitors are used as anticancer agents in dogs and cats. HYPOTHESIS: IHC is inaccurate for assessing tumor-associated COX-2 protein and enzymatic activity. METHODS: Five mammalian cell lines were assessed for COX-2 protein expression by IHC and Western blot analysis (WB), and functional COX-2 activity was based upon PGE2 production. RESULTS: Detection of COX-2 protein by IHC and WB were in agreement in 4 of 5 cell lines. In 1 cell line that lacked COX-2 gene transcription because of promoter hypermethylation (HCT-116), IHC produced false-positive staining for COX-2 protein expression. Functional COX-2 enzymatic activity was dissociated from relative IHC-based COX-2 protein expression in 2 cell lines (RPMI 2650 and SCCF1). The RPMI 2650 cell line demonstrated strong COX-2 protein expression but minimal PGE2 production. CONCLUSIONS AND CLINICAL IMPORTANCE: Western blot is more accurate than IHC for the detection of COX-2 protein in the cell lines studied. Furthermore, the semiquantitative identification of COX-2 protein by IHC or WB does not necessarily correlate with enzymatic activity. Based upon the potential inaccuracy of IHC and dissociation of COX-2 protein expression from enzymatic activity, the practice of instituting treatment of tumors with COX-2 inhibitors based solely on IHC results should be reconsidered.