The mechanical stimulation of myotubes counteracts the effects of tumor-derived factors through the modulation of the activin/follistatin ratio

Activin negatively affects muscle fibers and progenitor cells in aging (sarcopenia) and in chronic diseases characterized by severe muscle wasting (cachexia). High circulating activin levels predict poor survival in cancer patients. However, the relative impact of activin in mediating muscle atrophy and hampered homeostasis is still unknown. To directly assess the involvement of activin, and its physiological inhibitor follistatin, in cancer-induced muscle atrophy, we cultured C2C12 myotubes in the absence or in the presence of a mechanical stretching stimulus and in the absence or presence of C26 tumor-derived factors (CM), so as to mimic the mechanical stimulation of exercise and cancer cachexia, respectively. We found that CM induces activin release by myotubes, further exacerbating the negative effects of tumor-derived factors. In addition, mechanical stimulation is sufficient to counteract the adverse tumor-induced effects on muscle cells, in association with an increased follistatin/activin ratio in the cell culture medium, indicating that myotubes actively release follistatin upon stretching. Recombinant follistatin counteracts tumor effects on myotubes exclusively by rescuing fusion index, suggesting that it is only partially responsible for the stretch-mediated rescue. Therefore, besides activin, other tumor-derived factors may play a significant role in mediating muscle atrophy. In addition to increasing follistatin secretion mechanical stimulation induces additional beneficial responses in myotubes. We propose that in animal models of cancer cachexia and in cancer patients purely mechanical stimuli play an important role in mediating the rescue of the muscle homeostasis reported upon exercise

Both adiponectin and interleukin-10 inhibit LPS-induced activation of the NF-kappa B pathway in 3T3-L1 adipocytes

Adiponectin and interleukin 10 (IL-10) are adipokines that are predominantly secreted by differentiated adipocytes and are involved in energy homeostasis, insulin sensitivity, and the anti-inflammatory response. These two adipokines are reduced in obese subjects, which favors increased activation of nuclear factor kappa B (NF-kappa B) and leads to elevation of pro-inflammatory adipokines. However, the effects of adiponectin and IL-10 on NF-kappa B DNA binding activity (NF-kappa Bp50 and NF-kappa Bp65) and proteins involved with the toll-like receptor (TLR-2 and TLR-4) pathway, such as MYD88 and TRAF6 expression, in lipopolysaccharide-treated 3T3-L1 adipocytes are unknown. Stimulation of lipopolysaccharide-treated 3T3-L1 adipocytes for 24 h elevated IL-6 levels; activated the NF-kappa B pathway cascade; increased protein expression of IL-6R, TLR-4, MYD88, and TRAF6; and increased the nuclear activity of NF-kappa B (p50 and p65) DNA binding. Adiponectin and IL-10 inhibited the elevation of IL-6 levels and activated NF-kappa B (p50 and p65) DNA binding. Taken together, the present results provide evidence that adiponectin and IL-10 have an important role in the anti-inflammatory response in adipocytes. in addition, inhibition of NF-kappa B signaling pathways may be an excellent strategy for the treatment of inflammation in obese individuals. (C) 2011 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Fis, BR-04023060 São Paulo, BrazilUniv São Paulo, Inst Biomed Sci, Canc & Metab Grp, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Fis, BR-04023060 São Paulo, BrazilFAPESP: 08/54733-0Web of Scienc

Lipases and lipid droplet-associated protein expression in subcutaneous white adipose tissue of cachectic patients with cancer

Background: Cancer cachexia is a multifactorial metabolic syndrome characterized by marked loss of adipose tissue and skeletal muscle. Fat loss from adipose tissue in cancer cachexia is partly the result of increased lipolysis. Despite the growing amount of studies focused on elucidating the mechanisms through which lipolysis-related proteins regulate the lipolytic process, there are scarce data concerning that profile in the adipose tissue of cancer cachectic patients. Considering its fundamental importance, it was our main purpose to characterize the expression of the lipolysis-related proteins in the white adipose tissue of cachectic cancer patients. Methods: Patients from the University Hospital were divided into three groups: control, cancer cachexia (CC), and weight-stable cancer patients (WSC). To gain greater insight into adipose tissue wasting during cancer cachexia progression, we have also analyzed an experimental model of cachexia (Walker 256 carcinosarcoma). Animals were divided into: control, intermediate cachexia (IC) and terminal cachexia (TC). Subcutaneous white adipose tissue of patients and epidydimal white adipose tissue of animals were investigated regarding molecular aspects by determining the protein content and gene expression of hormone-sensitive lipase (HSL), adipose triglyceride lipase (ATGL), comparative gene identification-58 (CGI-58), perilipin 1, leptin, adiponectin, visfatin, and tumour necrosis factor alpha (TNF-alpha). Results: We found augmented lipolysis in CC associated with increased HSL expression, as well as upregulation of ATGL expression and reduction in perilipin 1 content. In IC, there was an imbalance in the secretion of pro-and anti-inflammatory factors. The alterations at the end-stage of cachexia were even more profound, and there was a reduction in the expression of almost all proteins analyzed in the animals. Conclusions: Our findings show that cachexia induces important morphological, molecular, and humoral alterations in the white adipose tissue, which are specific to the stage of the syndrome.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ São Paulo, Canc Metab Res Grp, Inst Biomed Sci, Dept Surg,Fac Med, São Paulo, BrazilSão Paulo State Univ UNESP, Exercise & Immunometab Res Grp, Dept Phys Educ, Presidente Prudente, SP, BrazilUniv Fed São Paulo, UNIFESP, Dept Fisiol, São Paulo, BrazilUniv São Paulo, Univ Hosp, Dept Clin Surg, São Paulo, BrazilUniv Mogi das Cruzes, Lab Adipose Tissue Biol, Ctr Integrated Biotechnol, Mogi Das Cruzes, BrazilUniv São Paulo, Inst Biomed Sci, Ave Prof Lineu Prestes 1524,Lab 434, BR-05508900 São Paulo, SP, BrazilUniv Fed São Paulo, UNIFESP, Dept Fisiol, São Paulo, BrazilFAPESP: 2012/50079-0Web of Scienc

Endotoxin levels correlate positively with a sedentary lifestyle and negatively with highly trained subjects

Introduction: A sedentary lifestyle increases the risk of developing cardiovascular disease, obesity, and diabetes. This phenomenon is supported by recent studies suggesting a chronic, low-grade inflammation status. Endotoxin derived from gut flora may be key to the development of inflammation by stimulating the secretion of inflammatory factors. This study aimed to examine plasma inflammatory markers and endotoxin levels in individuals with a sedentary lifestyle and/or in highly trained subjects at rest. Methods: Fourteen male subjects (sedentary lifestyle n = 7; highly trained subjects n = 7) were recruited. Blood samples were collected after an overnight fast (similar to 12 h). the plasmatic endotoxin, plasminogen activator inhibitor type-1 (PAI-1), monocyte chemotactic protein-1 (MCP1), ICAM/CD54, VCAM/CD106 and lipid profile levels were determined.Results: Endotoxinemia was lower in the highly trained subject group relative to the sedentary subjects (p < 0.002). in addition, we observed a positive correlation between endotoxin and PAI-1 (r = 0.85, p < 0.0001), endotoxin and total cholesterol (r = 0.65; p < 0.01), endotoxin and LDL-c (r = 0.55; p < 0.049) and endotoxin and TG levels (r = 0.90; p < 0.0001). the plasma levels of MCP-1, ICAM/CD54 and VCAM/CD106 did not differ.Conclusion: These results indicate that a lifestyle associated with high-intensity and high-volume exercise induces favorable changes in chronic low-grade inflammation markers and may reduce the risk for diseases such as obesity, diabetes and cardiovascular diseases.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Physiol, Div Nutr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biosci, São Paulo, BrazilUniv São Paulo, Canc Metab Grp, Inst Biomed Sci, Dept Cell & Dev Biol, BR-05508 São Paulo, BrazilUniv Prebiteriana Mackenzie, Dept Phys Educ, Biol & Hlth Sci Ctr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Physiol, Div Nutr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biosci, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilFAPESP: 2008/03533-1Web of Scienc

A modified hydrogel production protocol to decrease cellular content

PURPOSE: To analyze the cytotoxicity and cell in porcine-derived decellularized skin matrix. METHODS: We analyzed the effect of multiple decellularization processes by histological analysis, DNA quantification, and flow cytometry. Subsequently, we analyzed the most appropriate hydrogel concentration to minimize cytotoxicity on fibroblast culture and to maximize cell proliferation. RESULTS: After the fourth decellularization, the DNA quantification showed the lowest DNA concentration (< 50 ng/mg). Histological analysis showed no cell components in the hydrogel. Moreover, hematoxylin and eosin showed a heterogeneous structure of collagen fibers. The best hydrogel concentration ranged from 3 to 25%, and there was no significant difference between the 24 hours and seven days. CONCLUSIONS: The process of hydrogel production was effective for removing cells and DNA elements. The best hydrogel concentration ranged from 3 to 25%

Pioglitazone Treatment Increases Survival and Prevents Body Weight Loss in Tumor-Bearing Animals: Possible Anti-Cachectic Effect

Cachexia is a multifactorial syndrome characterized by profound involuntary weight loss, fat depletion, skeletal muscle wasting, and asthenia; all symptoms are not entirely attributable to inadequate nutritional intake. Adipose tissue and skeletal muscle loss during cancer cachexia development has been described systematically. the former was proposed to precede and be more rapid than the latter, which presents a means for the early detection of cachexia in cancer patients. Recently, pioglitazone (PGZ) was proposed to exhibit anticancer properties, including a reduction in insulin resistance and adipose tissue loss; nevertheless, few studies have evaluated its effect on survival. for greater insight into a potential anti-cachectic effect due to PGZ, 8-week-old male Wistar rats were subcutaneously inoculated with 1 mL (2x10(7)) of Walker 256 tumor cells. the animals were randomly assigned to two experimental groups: TC (tumor + saline-control) and TP5 (tumor + PGZ/5 mg). Body weight, food ingestion and tumor growth were measured at baseline and after removal of tumor on days 7, 14 and 26. Samples from different visceral adipose tissue (AT) depots were collected on days 7 and 14 and stored at -80oC (5 to 7 animals per day/group). the PGZ treatment showed an increase in the survival average of 27.3%(P<0.01) when compared to TC. It was also associated with enhanced body mass preservation (40.7 and 56.3%, p<0.01) on day 14 and 26 compared with the TC group. the treatment also reduced the final tumor mass (53.4%, p<0.05) and anorexia compared with the TC group during late-stage cachexia. the retroperitoneal AT (RPAT) mass was preserved on day 7 compared with the TC group during the same experimental period. Such effect also demonstrates inverse relationship with tumor growth, on day 14. Gene expression of PPAR-gamma, adiponectin, LPL and C/EBP-alpha from cachectic rats was upregulated after PGZ. Glucose uptake from adipocyte cells (RPAT) was entirely re-established due to PGZ treatment. Taken together, the results demonstrate beneficial effects of PGZ treatment at both the early and final stages of cachexia.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Mogi das Cruzes, Integrated Grp Biotechnol, Lab Adipose Tissue Biol, Mogi Das Cruzes, BrazilUniv São Paulo, Inst Biomed Sci, Canc Metab Res Grp, São Paulo, BrazilUniv São Paulo, Inst Biomed Sci, Physiol Lab, São Paulo, BrazilUniv Estadual Maringa, Dept Physiol Sci, Maringa, Parana, BrazilUniversidade Federal de São Paulo, Dept Biomed Engn, Sao Jose Dos Campos, BrazilBoston Sch Med, Dept Biochem, Boston, MA USAUniversidade Federal de São Paulo, Dept Biomed Engn, Sao Jose Dos Campos, BrazilFAPESP: 2010/51078-1FAPESP: 2008/54091-9FAPESP: 2012/51094-1Web of Scienc

Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents

Aim: the purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy.Design: the present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15-19 y) with a body mass index >95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. in addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR).Results: the most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. in addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels.Conclusions: the present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. in addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Dept Fisiol, São Paulo, BrazilDept Biociencias, São Paulo, BrazilDept Psicobiol, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, São Paulo, BrazilICB Univ São Paulo USP, Grp Metab & Canc, São Paulo, BrazilUniv So Santa Catarina, Hlth Sci Unit, Lab Exercise Biochem & Physiol, Criciuma, SC, BrazilUniversidade Federal de São Paulo UNIFESP, São Paulo, BrazilFAPESP: 2011/50356-0FAPESP: 2011/50414-0Web of Scienc

Effects of high-intensity intermittent training on carnitine palmitoyl transferase activity in the gastrocnemius muscle of rats

We examined the capacity of high-intensity intermittent training (HI-IT) to facilitate the delivery of lipids to enzymes responsible for oxidation, a task performed by the carnitine palmitoyl transferase (CPT) system in the rat gastrocnemius muscle. Male adult Wistar rats (160-250 g) were randomly distributed into 3 groups: sedentary (Sed, N = 5), HI-IT (N = 10), and moderate-intensity continuous training (MI-CT, N = 10). The trained groups were exercised for 8 weeks with a 10% (HI-IT) and a 5% (MI-CT) overload. The HI-IT group presented 11.8% decreased weight gain compared to the Sed group. The maximal activities of CPT-I, CPT-II, and citrate synthase were all increased in the HI-IT group compared to the Sed group (P < 0.01), as also was gene expression, measured by RT-PCR, of fatty acid binding protein (FABP; P < 0.01) and lipoprotein lipase (LPL; P < 0.05). Lactate dehydrogenase also presented a higher maximal activity (nmol·min-1·mg protein-1) in HI-IT (around 83%). We suggest that 8 weeks of HI-IT enhance mitochondrial lipid transport capacity thus facilitating the oxidation process in the gastrocnemius muscle. This adaptation may also be associated with the decrease in weight gain observed in the animals and was concomitant to a higher gene expression of both FABP and LPL in HI-IT, suggesting that intermittent exercise is a "time-efficient" strategy inducing metabolic adaptation