Cancer cachexia induces morphological and inflammatory changes in the intestinal mucosa.

BACKGROUND: Cachexia is a multifactorial and multiorgan syndrome associated with cancer and other chronic diseases and characterized by severe involuntary body weight loss, disrupted metabolism, inflammation, anorexia, fatigue, and diminished quality of life. This syndrome affects around 50% of patients with colon cancer and is directly responsible for the death of at least 20% of all cancer patients. Systemic inflammation has been recently proposed to underline most of cachexia-related symptoms. Nevertheless, the exact mechanisms leading to the initiation of systemic inflammation have not yet been unveiled, as patients bearing the same tumour and disease stage may or may not present cachexia. We hypothesize a role for gut barrier disruption, which may elicit persistent immune activation in the host. To address this hypothesis, we analysed the healthy colon tissue, adjacent to the tumour. METHODS: Blood and rectosigmoid colon samples (20 cm distal to tumour margin) obtained during surgery, from cachectic (CC = 25) or weight stable (WSC = 20) colon cancer patients, who signed the informed consent form, were submitted to morphological (light microscopy), immunological (immunohistochemistry and flow cytometry), and molecular (quantification of inflammatory factors by Luminex® xMAP) analyses. RESULTS: There was no statistical difference in gender and age between groups. The content of plasma interleukin 6 (IL-6) and IL-8 was augmented in cachectic patients relative to those with stable weight (P = 0.047 and P = 0.009, respectively). The number of lymphocytic aggregates/field in the gut mucosa was higher in CC than in WSC (P = 0.019), in addition to those of the lamina propria (LP) eosinophils (P < 0.001) and fibroblasts (P < 0.001). The area occupied by goblet cells in the colon mucosa was decreased in CC (P = 0.016). The M1M2 macrophages percentage was increased in the colon of CC, in relation to WSC (P = 0.042). Protein expression of IL-7, IL-13, and transforming growth factor beta 3 in the colon was significantly increased in CC, compared with WSC (P = 0.02, P = 0.048, and P = 0.048, respectively), and a trend towards a higher content of granulocyte-colony stimulating factor in CC was also observed (P = 0.061). The results suggest an increased recruitment of immune cells to the colonic mucosa in CC, as compared with WSC, in a fashion that resembles repair response following injury, with higher tissue content of IL-13 and transforming growth factor beta 3. CONCLUSIONS: The changes in the intestinal mucosa cellularity, along with modified cytokine expression in cachexia, indicate that gut barrier alterations are associated with the syndrome.

Tumour-derived transforming growth factor-ß signalling contributes to fibrosis in patients with cancer cachexia.

BACKGROUND: Cachexia is a paraneoplastic syndrome related with poor prognosis. The tumour micro-environment contributes to systemic inflammation and increased oxidative stress as well as to fibrosis. The aim of the present study was to characterise the inflammatory circulating factors and tumour micro-environment profile, as potentially contributing to tumour fibrosis in cachectic cancer patients. METHODS: 74 patients (weight stable cancer n = 31; cachectic cancer n = 43) diagnosed with colorectal cancer were recruited, and tumour biopsies were collected during surgery. Multiplex assay was performed to study inflammatory cytokines and growth factors. Immunohistochemistry analysis was carried out to study extracellular matrix components. RESULTS: Higher protein expression of inflammatory cytokines and growth factors such as epidermal growth factor, granulocyte-macrophage colony-stimulating factor, interferon-α, and interleukin (IL)-8 was observed in the tumour and serum of cachectic cancer patients in comparison with weight-stable counterparts. Also, IL-8 was positively correlated with weight loss in cachectic patients (P = 0.04; r = 0.627). Immunohistochemistry staining showed intense collagen deposition (P = 0.0006) and increased presence of α-smooth muscle actin (P < 0.0001) in tumours of cachectic cancer patients, characterizing fibrosis. In addition, higher transforming growth factor (TGF)-ß1, TGF-ß2, and TGF-ß3 expression (P = 0.003, P = 0.05, and P = 0.047, respectively) was found in the tumour of cachectic patients, parallel to p38 mitogen-activated protein kinase alteration. Hypoxia-inducible factor-1α mRNA content was significantly increased in the tumour of cachectic patients, when compared with weight-stable group (P = 0.005). CONCLUSIONS: Our results demonstrate TGF-ß pathway activation in the tumour in cachexia, through the (non-canonical) mitogen-activated protein kinase pathway. The results show that during cachexia, intratumoural inflammatory response contributes to the onset of fibrosis. Tumour remodelling, probably by TGF-ß-induced transdifferentiation of fibroblasts to myofibroblasts, induces unbalanced inflammatory cytokine profile, angiogenesis, and elevation of extracellular matrix components (EMC). We speculate that these changes may affect tumour aggressiveness and present consequences in peripheral organs.

Pequi (Caryocar brasiliense Camb.) almond oil attenuates carbon tetrachloride-induced acute hepatic injury in rats: Antioxidant and anti-inflammatory effects.

Carbon tetrachloride (CCl4) is a potent hepatotoxin, capable of generating free radicals that lead to oxidative stress and the inflammation process. Pequi almond oil (PAO) has been reported to possess unsaturated fatty acid and antioxidant compounds related to beneficial effects on oxidation and inflammatory conditions. The present study was undertaken to evaluate the hepatoprotective effects of handmade and coldpressed PAO on CCl4-induced acute liver injury. The possible mechanisms underlying the effect on liver injury enzymes, histopathological parameters, lipid profile, lipid peroxidation, and antioxidant and detoxification defense systems, as well as inflammatory parameters, were determined. Rats treated with PAO (3 or 6 mL/kg) for 21 days before CCl4 induction (3 mL/kg, 70%) showed significantly decreased levels of alanine aminotransferase and aspartate aminotransferase, milder hepatic lesions and higher levels of serum high-density lipoprotein compared to CCl4 group. Moreover, PAO enhanced antioxidant capacity by increasing hepatic glutathione peroxidase and glutathione reductase enzyme activities, as well as reducing circulating concentrations of leptin and inflammatory mediators such as interleukin-6, leukotrienes -4 and -5 and the tumor necrosis factor receptor. In summary, PAO, especially cold-pressed oil, attenuated the CCl4-induced alterations in serum and hepatic tissue in rats due to its antioxidant and anti-inflammatory properties.

White adipose tissue cells and the progression of cachexia: inflammatory pathways.

BACKGROUND: Cachexia is a systemic syndrome leading to body wasting, systemic inflammation, and to metabolic chaos. It is a progressive condition, and little is known about its dynamics. Detection of the early signs of the disease may lead to the attenuation of the associated symptoms. The white adipose tissue is an organ with endocrine functions, capable of synthesising and secreting a plethora of proteins, including cytokines, chemokines, and adipokines. It is well established that different adipose tissue depots demonstrate heterogeneous responses to physiological and pathological stimuli. The present study aimed at providing insight into adipocyte involvement in inflammation along the progression of cachexia. METHODS: Eight-weeks-old male rats were subcutaneously inoculated with a Walker 256 carcinosarcoma cell suspension (2 × 10(7) cells in 1.0 mL; tumour-bearing, T) or Phosphate-buffered saline (control, C). The retroperitoneal, epididymal, and mesenteric adipose pads were excised on Days 0, 7, and 14 post-tumour cell injection, and the adipocytes were isolated. RESULTS: Mesenteric and epididymal adipocytes showed up-regulation of IL-1ß protein expression and activation of the inflammasome pathway, contributing for whole tissue inflammation. The stromal vascular fraction of the retroperitoneal adipose tissue, on the other hand, seems to be the major contributor for the inflammation in this specific pad. CONCLUSION: Adipocytes seem to play a relevant role in the establishment of white adipose tissue inflammation, through the activation of the NF-κB and inflammasome pathways. In epididymal adipocytes, induction of the inflammasome may be detected already on Day 7 post-tumour cell inoculation.

Cachexia-associated adipose tissue morphological rearrangement in gastrointestinal cancer patients.

BACKGROUND AND AIMS: Cachexia is a syndrome characterized by marked involuntary loss of body weight. Recently, adipose tissue (AT) wasting has been shown to occur before the appearance of other classical cachexia markers. We investigated the composition and rearrangement of the extracellular matrix, adipocyte morphology and inflammation in the subcutaneous AT (scAT) pad of gastrointestinal cancer patients. METHODS: Surgical biopsies for scAT were obtained from gastrointestinal cancer patients, who were signed up into the following groups: cancer cachexia (CC, n = 11), weight-stable cancer (WSC, n = 9) and weight-stable control (non-cancer) (control, n = 7). The stable weight groups were considered as those with no important weight change during the last year and body mass index <25 kg/m(2). Subcutaneous AT fibrosis was quantified and characterized by quantitative PCR, histological analysis and immunohistochemistry. RESULTS: The degree of fibrosis and the distribution and collagen types (I and III) were different in WSC and CC patients. CC patients showed more pronounced fibrosis in comparison with WSC. Infiltrating macrophages surrounding adipocytes and CD3 Ly were found in the fibrotic areas of scAT. Subcutaneous AT fibrotic areas demonstrated increased monocyte chemotactic protein 1 (MCP-1) and Cluster of Differentiation (CD)68 gene expression in cancer patients. CONCLUSIONS: Our data indicate architectural modification consisting of fibrosis and inflammatory cell infiltration in scAT as induced by cachexia in gastrointestinal cancer patients. The latter was characterized by the presence of macrophages and lymphocytes, more evident in the fibrotic areas. In addition, increased MCP-1 and CD68 gene expression in scAT from cancer patients may indicate an important role of these markers in the early phases of cancer.

Systemic Inflammation in Cachexia - Is Tumor Cytokine Expression Profile the Culprit?

Cachexia affects about 80% of gastrointestinal cancer patients. This multifactorial syndrome resulting in involuntary and continuous weight loss is accompanied by systemic inflammation and immune cell infiltration in various tissues. Understanding the interactions among tumor, immune cells, and peripheral tissues could help attenuating systemic inflammation. Therefore, we investigated inflammation in the subcutaneous adipose tissue and in the tumor, in weight stable and cachectic cancer patients with same diagnosis, in order to establish correlations between tumor microenvironment and secretory pattern with adipose tissue and systemic inflammation. Infiltrating monocyte phenotypes of subcutaneous and tumor vascular-stromal fraction were identified by flow cytometry. Gene and protein expression of inflammatory and chemotactic factors was measured with qRT-PCR and Multiplex Magpix(®) system, respectively. Subcutaneous vascular-stromal fraction exhibited no differences in regard to macrophage subtypes, while in the tumor, the percentage of M2 macrophages was decreased in the cachectic patients, in comparison to weight-stable counterparts. CCL3, CCL4, and IL-1ß expression was higher in the adipose tissue and tumor tissue in the cachectic group. In both tissues, chemotactic factors were positively correlated with IL-1ß. Furthermore, positive correlations were found for the content of chemoattractants and cytokines in the tumor and adipose tissue. The results strongly suggest that the crosstalk between the tumor and peripheral tissues is more pronounced in cachectic patients, compared to weight-stable patients with the same tumor diagnosis.

Maternal postnatal high-fat diet, rather than gestational diet, affects morphology and mTOR pathway in skeletal muscle of weaning rat.

The positive regulation of insulin pathway in skeletal muscle results in increased activity of the mammalian target of rapamycin (mTOR), a positive effector of mRNA translation rate and protein synthesis. Studies that assess the activity of this protein in response to chronic high-fat diet (HFD) are scarce and controversial, and to date, there are no studies evaluating the mTOR pathway in infants exposed to gestational and postgestational HFD. This study investigated the effect of maternal HFD on skeletal muscle morphology and on phosphorylation of proteins that comprise the intracellular mTOR signaling pathway in soleus muscle of offspring at weaning. For this purpose, 10 days prior to conception, 39 female Wistar rats were randomly assigned to either control diet (CTL) or HFD. Later, rats were distributed into four groups according to gestational and postpregnancy diet: CTL/CTL (n=10), CTL/HF (n=11), HF/HF (n=10) and HF/CTL (n=8). After 21 days of lactation, pups were killed, and blood samples and soleus and gastrocnemius skeletal muscle were collected for analysis. We observed an influence of maternal postgestational diet, rather than gestational diet, in promoting an obese phenotype, characterized by body fat accumulation, insulin resistance and high serum leptin, glucose, triglycerides and cholesterol levels (P<.05). We have also detected alterations on skeletal muscle morphology--with reduced myofiber density--and impairment on S6 kinase 1 and 4E binding protein-1 phosphorylation (P<.05). These results emphasize the importance of maternal diet during lactation on muscle morphology and on physiological adaptations of infant rats.

Leucine supplementation improves adiponectin and total cholesterol concentrations despite the lack of changes in adiposity or glucose homeostasis in rats previously exposed to a high-fat diet.

BACKGROUND: Studies suggest that leucine supplementation (LS) has a therapeutic potential to prevent obesity and to promote glucose homeostasis. Furthermore, regular physical exercise is a widely accepted strategy for body weight maintenance and also for the prevention of obesity. The aim of this study was to determine the effect of chronic LS alone or combined with endurance training (ET) as potential approaches for reversing the insulin resistance and obesity induced by a high-fat diet (HFD) in rats. METHODS: Forty-seven rats were randomly divided into two groups. Animals were fed a control diet-low fat (n = 10) or HFD (n = 37). After 15 weeks on HFD, all rats received the control diet-low fat and were randomly divided according to treatment: reference (REF), LS, ET, and LS+ET (n = 7-8 rats per group). After 6 weeks of treatment, the animals were sacrificed and body composition, fat cell volume, and serum concentrations of total cholesterol, HDL-cholesterol, triacylglycerol, glucose, adiponectin, leptin and tumor necrosis factor-alpha (TNF-α) were analyzed. RESULTS: At the end of the sixth week of treatment, there was no significant difference in body weight between the REF, LS, ET and LS+ET groups. However, ET increased lean body mass in rats (P = 0.019). In addition, ET was more effective than LS in reducing adiposity (P = 0.019), serum insulin (P = 0.022) and TNF-α (P = 0.044). Conversely, LS increased serum adiponectin (P = 0.021) levels and reduced serum total cholesterol concentration (P = 0.042). CONCLUSIONS: The results showed that LS had no beneficial effects on insulin sensitivity or adiposity in previously obese rats. On the other hand, LS was effective in increasing adiponectin levels and in reducing total cholesterol concentration.