Cutaneous Application of Capsaicin Cream Reduces Clinical Signs of Experimental Colitis and Repairs Intestinal Barrier Integrity by Modulating the Gut Microbiota and Tight Junction Proteins.

Capsaicin, a pungent compound in chili peppers, is described as having potent anti-inflammatory, antioxidant, and antimicrobial properties. It is also described as a potential modulator of the immune system and intestinal microbiota. Oral or rectal administration of capsaicin has been studied to treat or prevent colitis. However, those vias are often not well accepted due to the burning sensation that capsaicin can cause. Our objective was to evaluate whether the application of capsaicin skin creams (0.075%) would be effective in improving inflammation and epithelial barrier function as well as the composition of the gut microbiota in a model of mild colitis induced by dextran sulfate sodium (1.5%). The results showed that the cutaneous application of capsaicin reversed weight loss and decreased colon shortening and diarrhea, all typical signs of colitis. There was also an improvement in the intestinal epithelial barrier, preserving proteins from tight junctions. We also evaluated the biodistribution of 99mtechnetium-radiolabeled capsaicin (99mTc-CAPS) applied to the back skin of the animals. We found significant concentrations of 99 mTc-Cap in the colon and small intestine after 2 and 4 h of administration. In addition, there was an increased expression of capsaicin receptor TRPV1 in the colon. Moreover, animals with colitis receiving cutaneous capsaicin presented a better short-chain fatty acid profile and increased levels of SIgA, suggesting increased microbiota diversity. In conclusion, our work opens avenues for further studies to better understand capsaicin's potential benefits and mechanisms in addressing colitis through cutaneous application.

Kinkan orange protects hypercholesterolemic rats against dyslipidemia and oxidative stress.

We investigated the effect of dietary supplementation with kinkan orange on growth, adiposity, metabolic parameters, and oxidative stress in rats with diet-induced hypercholesterolemia. Female Wistar rats (6-8 weeks) were fed a AIN-93M diet (Control); AIN-93M diet containing 5% kinkan orange (CTkinkan); Hypercholesterolemic diet, containing 1% cholesterol and 25% fat (Hyper); or Hypercholesterolemic diet containing 5% kinkan orange (Hyperkinkan). Hypercholesterolemic diet increased body weight, adiposity, serum alanine transaminase (ALT), creatinine, cholesterol and triglycerides, hepatic total lipids, cholesterol, and triglycerides, and hepatic oxidative stress. Supplementation with kinkan reduced the serum and hepatic lipid content, decreased serum ALT, besides improving the antioxidant status in liver tissue of hypercholesterolemic animals. Moreover, HDL-cholesterol increased in both groups supplemented with kinkan orange (CTkinkan and Hyperkinkan). Our data suggest that diet supplementation with kinkan orange may consist of a valid strategy to prevent or reduce dyslipidemia and oxidative stress in hypercholesterolemic rats.

Wheat gluten intake increases the severity of experimental colitis and bacterial translocation by weakening of the proteins of the junctional complex.

Gluten is only partially digested by intestinal enzymes and can generate peptides that can alter intestinal permeability, facilitating bacterial translocation, thus affecting the immune system. Few studies addressed the role of diet with gluten in the development of colitis. Therefore, we investigate the effects of wheat gluten-containing diet on the evolution of sodium dextran sulphate (DSS)-induced colitis. Mice were fed a standard diet without (colitis group) or with 4·5 % wheat gluten (colitis + gluten) for 15 d and received DSS solution (1·5 %, w/v) instead of water during the last 7 d. Compared with the colitis group, colitis + gluten mice presented a worse clinical score, a larger extension of colonic injury area, and increased mucosal inflammation. Both intestinal permeability and bacterial translocation were increased, propitiating bacteria migration for peripheral organs. The mechanism by which diet with gluten exacerbates colitis appears to be related to changes in protein production and organisation in adhesion junctions and desmosomes. The protein α-E-catenin was especially reduced in mice fed gluten, which compromised the localisation of E-cadherin and ß-catenin proteins, weakening the structure of desmosomes. The epithelial damage caused by gluten included shortening of microvilli, a high number of digestive vacuoles, and changes in the endosome/lysosome system. In conclusion, our results show that wheat gluten-containing diet exacerbates the mucosal damage caused by colitis, reducing intestinal barrier function and increasing bacterial translocation. These effects are related to the induction of weakness and disorganisation of adhesion junctions and desmosomes as well as shortening of microvilli and modification of the endocytic vesicle route.

Oral butyrate reduces oxidative stress in atherosclerotic lesion sites by a mechanism involving NADPH oxidase down-regulation in endothelial cells.

Butyrate is a 4-carbon fatty acid that has antiinflammatory and antioxidative properties. It has been demonstrated that butyrate is able to reduce atherosclerotic development in animal models by reducing inflammatory factors. However, the contribution of its antioxidative effects of butyrate on atherogenesis has not yet been studied. We investigated the influence of butyrate on oxidative status, reactive oxygen species (ROS) release and oxidative enzymes (NADPH oxidase and iNOS) in atherosclerotic lesions of ApoE(-/-) mice and in oxLDL-stimulated peritoneal macrophages and endothelial cells (EA.hy926). The lesion area in aorta was reduced while in the aortic valve, although lesion area was unaltered, superoxide production and protein nitrosylation were reduced in butyrate-supplemented mice. Peritoneal macrophages from the butyrate group presented a lower free radical release after zymosan stimulus. When endothelial cells were pretreated with butyrate before oxLDL stimulus, the CCL-2 and superoxide ion productions and NADPH oxidase subunit p22phox were reduced. In macrophage cultures, in addition to a reduction in ROS release, nitric oxide and iNOS expression were down-regulated. The data suggest that one mechanism related to the effect of butyrate on atherosclerotic development is the reduction of oxidative stress in the lesion site. The reduction of oxidative stress related to NADPH oxidase and iNOS expression levels associated to butyrate supplementation attenuates endothelium dysfunction and macrophage migration and activation in the lesion site.

Mas receptor deficiency is associated with worsening of lipid profile and severe hepatic steatosis in ApoE-knockout mice.

The classical renin-angiotensin system pathway has been recently updated with the identification of additional molecules [such as angiotensin converting enzyme 2, ANG-(1-7), and Mas receptor] that might improve some pathophysiological processes in chronic inflammatory diseases. In the present study, we focused on the potential protective role of Mas receptor activation on mouse lipid profile, liver steatosis, and atherogenesis. Mas/apolipoprotein E (ApoE)-double-knockout (DKO) mice (based on C57BL/6 strain of 20 wk of age) were fed under normal diet and compared with aged-matched Mas and ApoE-single-knockout (KO), as well as wild-type mice. Mas/ApoE double deficiency was associated with increased serum levels of atherogenic fractions of cholesterol, triglycerides, and fasting glucose compared with wild-type or single KO. Serum levels of HDL or leptin in DKO were lower than in other groups. Hepatic lipid content as well as alanine aminotransferase serum levels were increased in DKO compared with wild-type or single-KO animals. Accordingly, the hepatic protein content of mediators related to atherosclerotic inflammation, such as peroxisome proliferator-activated receptor-α and liver X receptor, was altered in an adverse way in DKO compared with ApoE-KO. On the other hand, DKO mice did not display increased atherogenesis and intraplaque inflammation compared with ApoE-KO group. In conclusion, Mas deletion in ApoE-KO mice was associated with development of severe liver steatosis and dyslipidemia without affecting concomitant atherosclerosis. Mas receptor activation might represent promising strategies for future treatments targeting both hepatic and metabolic alterations in chronic conditions clustering these disorders.

Differences in adipose tissue inflammation and oxidative status in C57BL/6 and ApoE-/- mice fed high fat diet.

Apolipoprotein E deficient (Apo E-/-) mice are more resistant to the development of obesity compared to C57BL/6 wild type mice. They also hold a high basal oxidative status due to the loss of antioxidant action of apolipoprotein E. Since obesity is also an inducer of inflammation, we studied the effect of high-fat diet on obesity and oxidative stress in C57BL/6 and Apo E-/- mice for 9 weeks. The results confirmed that Apo E-/- mice fed high-fat diet are more resistant to the increase of both body weight and adiposity compared to C57BL/6 mice. Despite this, Apo E-/- mice presented a higher basal oxidative stress that was enhanced by high-fat diet. Macrophage infiltration, macrophage forming crown-like structures and proinflammatory adipokines (interleukin 6 and tumor necrosis factor alpha) were all higher in adipose tissue from Apo E-/- compared to C57BL/6 mice, regardless of diet type. In conclusion, although Apo E-/- mice are more resistant to becoming obese, they develop more severe adipose tissue inflammation companied by its consequences.

Pro-inflammatory effects of the mushroom Agaricus blazei and its consequences on atherosclerosis development.

PURPOSE: Extracts of the mushroom Agaricus blazei (A. blazei) have been described as possessing immunomodulatory and potentially cancer-protective activities. However, these effects of A. blazei as a functional food have not been fully investigated in vivo. METHODS: Using apolipoprotein E-deficient (ApoE(-/-)) mice, an experimental model of atherosclerosis, we evaluated the effects of 6 or 12 weeks of A. blazei supplementation on the activation of immune cells in the spleen and blood and on the development of atherosclerosis. RESULTS: Food intake, weight gain, blood lipid profile, and glycemia were similar between the groups. To evaluate leukocyte homing and activation, mice were injected with (99m)Tc-radiolabeled leukocytes, which showed enhanced leukocyte migration to the spleen and heart of A. blazei-supplemented animals. Analysis of the spleen showed higher levels of activation of neutrophils, NKT cells, and monocytes as well as increased production of TNF-α and IFN-γ. Circulating NKT cells and monocytes were also more activated in the supplemented group. Atherosclerotic lesion areas were larger in the aorta of supplemented mice and exhibited increased numbers of macrophages and neutrophils and a thinner fibrous cap. A. blazei-induced transcriptional upregulation of molecules linked to macrophage activation (CD36, TLR4), neutrophil chemotaxy (CXCL1), leukocyte adhesion (VCAM-1), and plaque vulnerability (MMP9) were seen after 12 weeks of supplementation. CONCLUSIONS: This is the first in vivo study showing that the immunostimulatory effect of A. blazei has proatherogenic repercussions. A. blazei enhances local and systemic inflammation, upregulating pro-inflammatory molecules, and enhancing leukocyte homing to atherosclerosis sites without affecting the lipoprotein profile.

The combination of high-fat diet-induced obesity and chronic ulcerative colitis reciprocally exacerbates adipose tissue and colon inflammation.

BACKGROUND: This study evaluated the relationship between ulcerative colitis and obesity, which are both chronic diseases characterized by inflammation and increases in immune cells and pro-inflammatory cytokines. METHODS: Mice with chronic ulcerative colitis induced by 2 cycles of dextran sodium sulfate (DSS) in the first and fourth week of the experiment were fed a high-fat diet (HFD) to induce obesity by 8 weeks. The animals were divided into 4 \ groups (control, colitis, HFD and colitis + HFD). RESULTS: Obesity alone did not raise histopathology scores, but the combination of obesity and colitis worsened the scores in the colon compared to colitis group. Despite the reduction in weight gain, there was increased inflammatory infiltrate in both the colon and visceral adipose tissue of colitis + HFD mice due to increased infiltration of macrophages, neutrophils and lymphocytes. Intravital microscopy of VAT microvasculature showed an increase in leukocyte adhesion and rolling and overexpression of adhesion molecules compared to other groups. Moreover, circulating lymphocytes, monocytes and neutrophils in the spleen and cecal lymph nodes were increased in the colitis + HFD group. CONCLUSION: Our results demonstrated the relationship between ulcerative colitis and obesity as aggravating factors for each disease, with increased inflammation in the colon and adipose tissue and systemic alterations observed in the spleen, lymph nodes and bloodstream.