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Oxidative stress role on metformin process of dacarbazine (DTIC) inducing resistance of B16F10 melanoma murine cells are investigated. To induce resistance to DTIC, murine melanoma cells were exposed to increasing concentrations of dacarabazine (DTIC-res group). Metformin was administered before and during the induction of resistance to DTIC (MET-DTIC). The oxidative stress parameters of the DTIC-res group showed increased levels of malondialdehyde (MDA), thiol, and reduced nuclear p53, 8-hydroxy-2'-deoxyguanosine (8-OH-DG), nuclear factor kappa B (NF-ĸB), and Nrf2. In presence of metformin in the resistant induction process to DTIC, (MET-DTIC) cells had increased antioxidant thiols, MDA, nuclear p53, 8-OH-DG, Nrf2, and reducing NF-ĸB, weakening the DTIC-resistant phenotype. The exclusive administration of metformin (MET group) also induced the cellular resistance to DTIC. The MET group presented high levels of total thiols, MDA, and reduced percentage of nuclear p53. It also presented reduced nuclear 8-OH-DG, NF-ĸB, and Nrf2 when compared with the control. Oxidative stress and the studied biomarkers seem to be part of the alterations evidenced in DTIC-resistant B16F10 cells. In addition, metformin administration is able to play a dual role according to the experimental protocol, preventing or inducing a DTIC-resistant phenotype. These findings should help future research with the aim of investigating DTIC resistance in melanoma.

Papillary thyroid carcinoma (PTC) is the most frequent subtype of thyroid cancer; Hashimoto's thyroiditis (HT), autoimmune disease, commonly affects the thyroid gland; there is possibly a correlation between both, but the exact mechanisms that involve this relationship are still under debate. Since oxidative stress (OS) and the inflammatory environment participate in the development of several types of cancer, the objective of the present study was to establish the microenvironment and systemic participation of OS and inflammatory markers in patients with PTC and HT.Blood and tissue samples were collected from 115 patients: BENIGN (n = 63); PTC (n = 27); HT (n = 15) and PTC + HT (n = 10), and sixty-three were samples from healthy individuals (control group).Superoxide dismutase, Catalase, reduced Glutathione, markers of lipid peroxidation and inflammation were evaluated in blood. Immunohistochemistry was performed on 3-nitrotyrosine, 4-hydroxynonenal, Ki-67 and VEGF. The results indicate that antioxidant enzymes were more active in groups with thyroid disorders compared to control, while the concentration of Reduced glutathione was reduced in BENIGN and PTC groups. When PTC and PTC + HT groups were analyzed, no significant differences were found in relation to the antioxidant defense and inflammatory markers. The ability to contain the induced lipid peroxidation was lower and a high level of malondialdehyde was observed in the PTC group. All immunohistochemical markers had higher scores in the PTC group compared to PTC + HT.There was a more pronounced presence of OS and a greater activity of cell proliferation and angiogenesis markers in PTC than in PTC + HT group.

Caffeine has been studied as a potentiating agent in chemotherapy against some types of cancer, but there are few reports on its effects on melanoma. This study aimed to investigate caffeine's ability to enhance the effects of dacarbazine in vitro.Murine melanoma B16F10 cells were treated 24 h with 1-40 µM caffeine. We evaluated cytotoxicity, DNA damage, apoptosis, and oxidative lesion induced by dacarbazine associated with caffeine. The metabolization of these drugs, as well as immunocytochemical labeling, were also evaluated.The pre-treatment with caffeine showed to be more effective. Caffeine potentiated dacarbazine-induced cytotoxic effects by increasing dacarbazine biotransformation, apoptosis, DNA damage, and malondialdehyde levels; also, caffeine reduced Ki67 and ERK1/2 nuclear labeling and increased p53 labeling in B16F10 cells. In our experiment, caffeine promoted modifications associated with dacarbazine metabolism by viable cells potentiating this antineoplastic drug. These promising results should be further evaluated in experimental models in vivo.

The epidemiological impact of viral diseases, combined with the emergence and reemergence of some viruses, and the difficulties in identifying effective therapies, have encouraged several studies to develop new therapeutic strategies for viral infections. In this context, the use of immunotherapy for the treatment of viral diseases is increasing. One of the strategies of immunotherapy is the use of antibodies, particularly the monoclonal antibodies (mAbs) and multi-specific antibodies, which bind directly to the viral antigen and bring about activation of the immune system. With current advancements in science and technology, several such antibodies are being tested, and some are already approved and are undergoing clinical trials. The present work aims to review the status of mAb development for the treatment of viral diseases.

Objective The aim of this study was to investigate the effects of creatine supplementation on early stages of ethanol-induced hepatic damage. Methods Male Swiss mice were divided into three groups (n = 12/group): control (C), ethanol (E), and ethanol supplemented with creatine (EC). The control group received a diet containing 15.8% of total calories from proteins, 46.3% from carbohydrates, and 37.9% from lipids. The ethanol and ethanol and creatine groups received diets containing 15.8% of total calories from proteins, 16.2% from carbohydrates, and 34.5% from lipids; the remaining calories were obtained from the addition of 5% of 95% ethanol. Creatine (1%; weight/vol) was added to the diet of EC mice. After 14 and 28 d, six animals from each group were sacrificed, generating subdivisions in each group: C14 and C28, E14 and E28, EC14 and EC28. After sacrifice, the liver was removed, weighed, and prepared for histologic, biochemical, and molecular analysis, and blood was collected. Results Ethanol intake induced mild cell degeneration, liver damage, oxidative lesions, and inflammation. Surprisingly, ethanol intake combined with creatine exacerbated cell degeneration and fat accumulation, hepatic expression of genes related to ethanol metabolism, oxidative stress and inflammation, and promoted oxidative stress and elevated plasma alanine aminotransferase (P Conclusion Creatine supplementation associated with ethanol is able to interfere in the alcohol metabolism and oxidative stress and to exacerbate ethanol-induced hepatic damage. These new findings are opposite to those observed in several studies where protective effects of creatine in a wide variety of injury models, including non-alcoholic fatty liver disease, were described.

Although resistance exercise (RE) is now recognized as an adjuvant in cancer treatment because of its capacity to prevent muscle wasting, weakness, and cachexia, it is unknown whether RE can mitigate tumor development. Two solid adenocarcinoma models (Walker-256 and Ehrlich) were used to investigate the effects of RE on tumor cell proliferation, growth, and aggressiveness parameters in tumor-bearing animals' life span.Walker-256 tumor-bearing rats and Ehrlich tumor-bearing mice were subjected to RE, which consisted of climbing a ladder apparatus with loads tied to their tails. After 4 wk, animals were euthanized, and tumors were excised and assessed for tumor microenvironment evaluation such as cell proliferation and apoptosis determination, collagen deposit, and presence of malignant tumor morphology.Our data demonstrate that RE mitigated tumor growth and favored tumor end points such as lower Scarff-Bloom-Richardson histological grade tumor, denoting slow cell aberrant form and division, decreased tumor cell proliferation (evaluated by nucleus marked with antigen ki-67), and lower viable tumor area in both types of tumors studied. In addition, RE stimulated tumor microvessel density in Walker-256 tumor-bearing rats, but there was no change in their life span.RE may mitigate tumor growth and tumor malignancy parameters such as lower histopathological grade, assuming less nuclear pleomorphism and mitotic cells, smaller viable tumor area, and decreased tumor cell proliferation in both adenocarcinomas. In addition, RE induced tumor vascularization.

Made available in DSpace on 2022-04-29T08:30:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-01 Purpose This study aimed to determine the role of mammalian target of rapamycin (mTORC1) activation and catabolic markers in resistance training's (RT) antiatrophy effect during cachexia-induced muscle loss. Methods Myofiber atrophy was induced by injecting Walker 256 tumor cells into rats exposed or not exposed to the RT protocol of ladder climbing. The role of RT-induced anabolic stimulation was investigated in tumor-bearing rats with the mTORC1 inhibitor rapamycin, and cross-sectional areas of skeletal muscle were evaluated to identify atrophy or hypertrophy. Components of the mTORC1 and ubiquitin-proteasome pathways were assessed by real-time polymerase chain reaction or immunoblotting. Results Although RT prevented myofiber atrophy and impaired the strength of tumor-bearing rats, in healthy rats, it promoted activated mTORC1, as demonstrated by p70S6K's increased phosphorylation and myofiber's enlarged cross-sectional area. However, RT promoted no changes in the ratio of p70S6K to phospho-p70S6K protein expression while prevented myofiber atrophy in tumor-bearing rats. Beyond that, treatment with rapamycin did not preclude RT's preventive effect on myofiber atrophy in tumor-bearing rats. Thus, RT's ability to prevent cancer-induced myofiber atrophy seems to be independent of mTORC1's and p70S6K's activation. Indeed, RT's preventive effect on cancer-induced myofiber atrophy was associated with its capacity to attenuate elevated tumor necrosis factor a and interleukin 6 as well as to prevent oxidative damage in muscles and an elevated abundance of atrogin-1. Conclusions By inducing attenuated myofiber atrophy independent of mTORC1's signaling activation, RT prevents muscle atrophy during cancer by reducing inflammation, oxidative damage, and atrogin-1 expression. Department of Physical Education State University of Londrina Department of Physical Education Universidade Estadual Paulista (UNESP) Presidente Prudente Federal University of Mato Grosso Graduate Program of Health Sciences Faculty of Medicine State University of Londrina Department of General Pathology University of Porto Ciafel Faculty of Sport Department of Physical Education Universidade Estadual Paulista (UNESP) Presidente Prudente

Viral infections cause high morbidity and mortality, threaten public health, and impose a socioeconomic burden. We have seen the recent emergence of SARS‐CoV‐2 (Severe Acute Respiratory Syndrome Coronavirus 2), the causative agent of COVID‐19 that has already infected more than 29 million people, with more than 900 000 deaths since its identification in December 2019. Considering the significant impact of viral infections, research and development of new antivirals and control strategies are essential. In this paper, we summarize 96 antivirals approved by the Food and Drug Administration between 1987 and 2019. Of these, 49 (51%) are used in treatments against human immunodeficiency virus (HIV), four against human papillomavirus, six against cytomegalovirus, eight against hepatitis B virus, five against influenza, six against herpes simplex virus, 17 against hepatitis C virus and one against respiratory syncytial virus. This review also describes future perspectives for new antiviral therapies such as nanotechnologies, monoclonal antibodies and the CRISPR‐Cas system. These strategies are suggested as inhibitors of viral replication by various means, such as direct binding to the viral particle, blocking the infection, changes in intracellular mechanisms or viral genes, preventing replication and virion formation. We also observed that a large number of viral agents have no therapy available and the majority of those approved in the last 32 years are restricted to some groups, especially anti‐HIV. Additionally, the emergence of new viruses and strains resistant to available antivirals has necessitated the formulation of new antivirals.

Made available in DSpace on 2021-06-25T12:17:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Brazilian grants from SETI (Secretaria da Ciencia, Tecnologia e Ensino Superior do Parana) Ministry of Education Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Brazilian scholarship for a research internship at A.R.W.'s laboratory in Cleveland, USA Background: In 2019, the European Working Group on Sarcopenia in Older People (EWGSOP2) proposed low muscle strength as the primary outcome for sarcopenia diagnosis instead of low muscle mass, as proposed in 2010 (EWGSOP1). Therefore, the aim of this study was to compare the prevalence of sarcopenia using both EWGSOP1 and EWGSOP2 operational definitions in people living with HIV (PLHIV) and to determine the agreement and correlation between different tests proposed by EWGSOP2. Setting: Cross-sectional study, where 302 PLHIV (151 men), 51.7 +/- 9.0 years old were evaluated for the presence of sarcopenia using both EWGSOP1 and EWGSOP2 operational definitions. Methods: Appendicular skeletal muscle was estimated using bioimpedance analysis. Handgrip strength, chair stand, gait speed, and static balance were used as muscle function measures. Agreement was determined using Cohen kappa and Pearson correlation coefficient was calculated. Results: Sarcopenia prevalence was 4.3% using EWGSOP1 and 1.0% using EWGSOP2. Agreement for sarcopenia diagnosis between EWGSOP1 and EWGSOP2 was fair (k = 0.37, P < 0.01). From the 13 cases of sarcopenia diagnosed using EWGSOP1, only 3 cases (23.1%) were also diagnosed using EWGSOP2. A medium correlation (r = -0.32, P < 0.01) and poor agreement (k = 0.14, P < 0.01) between muscle strength tests (handgrip strength and chair stand) were observed. Concordance between handgrip and chair stand was observed in 11 participants only, whereas 65 participants were considered to have low muscle strength using chair stand but not using handgrip. Conclusions: Lower sarcopenia prevalence using EWGSOP2 and low agreement between EWGSOP1 and EWGSOP2 operational definitions in diagnosing sarcopenia were observed in PLHIV. Univ Estadual Londrina, Dept Phys Educ, Londrina, Parana, Brazil Case Western Reserve Univ, Frances Payne Bolton Sch Nursing, Res Campus,10900 Euclid Ave, Cleveland, OH 44106 USA Univ Estadual Londrina, Hlth Sci Ctr, Londrina, Parana, Brazil Salgado Inst Integral Hlth, Londrina, Parana, Brazil Univ Estadual Londrina, Biol Sci Ctr, Londrina, Parana, Brazil State Univ Sao Paulo, Dept Phys Educ, Presidente Pmdente, SP, Brazil Univ Colorado, Anschutz Med Campus, Aurora, CO USA State Univ Sao Paulo, Dept Phys Educ, Presidente Pmdente, SP, Brazil CAPES: 88881.132132/2016-01

To investigate the effects of caffeine on the proliferation and death of human breast cancer cells MCF-7 and MDA-MB-231. Cells were exposed to 1, 2.5, 5 and 10 mM of caffeine during 24 h, and oxidative stress (OS), cell proliferation and death, metabolic activity and DNA lesions were evaluated in the collected samples. Caffeine was cytotoxic to the cell lines analyzed, reducing cell proliferation and viability by interfering with the cellular metabolism and with lysosomal function. Although the cells presented different behaviors to treatment, in both cell lines, the drug induced OS and predominantly apoptosis. MCF-7 cells responded to OS induction (lipid peroxidation) increasing their antioxidant defenses. However, the OS generated induced oxidative DNA lesions, a finding not observed in MDA-MB-231 cells. The association of different scavengers with caffeine did not result in the recovery of cell viability, which suggests that it is not possible to attribute the caffeine induction of OS to only one of the specific ROS analyzed (superoxide anion, singlet oxygen and peroxyl radical). These results are promising and suggest that caffeine may be a good target for studies to prove its usefulness as an adjuvant in breast cancer treatment.

The ability to evade apoptosis is an important mechanism of drug resistance and tumor progression in breast cancer. The induction of different pathways of cell death could be an important strategy to limit tumor progression. Metformin, a drug used to treat type two diabetes, has demonstrated promising results in breast cancer experiments. However, little is known about the patterns of cell death induced by this drug. We analyzed the involvement of apoptosis, necroptosis and ferroptosis in the toxicity of metformin in MCF-7 cells, evaluating proliferation, viability and oxidative stress. It was used different inhibitors of cell death: Z-VAD, a pan-caspase inhibitor that blocks apoptosis; Necrostatin-1, which inhibits RIPK1 activity and blocks necroptosis; and the iron chelator, deferoxamine, that chelates iron and prevents ferroptosis. The participation of oxidative stress was analyzed through the evaluation of total thiols, reduced glutathione (GSH) and malondialdehyde (MDA). Our results showed that metformin increased cell death, reduced proliferation, thiol and GSH and increased MDA in cells. After the association between metformin and Z-VAD or Necrostatin-1, the drug toxicity was abolished. Ferroptosis did not significantly enrolled in metformin action against MCF-7 cells. The preservation of cellular antioxidants was found in all situations that cell death was blocked. Together, these results reveals that metformin induces necroptosis and apoptosis in MCF-7 cells and oxidative stress generation play a role in these two pathways of cell death. This information could help future studies to improve strategies to breast cancer treatment.

Thyroid cancer (TC) is the most prevalent malignant neoplasm that affects the endocrine system. Hashimoto's thyroiditis (HT), also known as chronic lymphocytic thyroiditis, is the most common autoimmune thyroid disease (AITD) that, together with Graves' disease (GD), represent the main autoimmune diseases that affect the thyroid gland. Some studies suggest a greater risk of AITD and the development of TC, while others, investigate its relationship with TC progression and patient prognosis. In this review, we have analyzed published data on the molecular aspects related to the association between AITD and TC, addressing their influence on TC progression, diagnosis, and prognosis of the patients. MEDLINE database (PubMed) platform was used as a search engine and the original articles related to the topic were selected using the keywords combination "thyroid cancer and Hashimoto thyroiditis" or "thyroid carcinoma and thyroid autoimmune disease". After the selection, we categorized the main findings of the papers into four topics: antitumor immunity, tumor progression, diagnosis, and prognosis. Although most of the studies have pointed out the presence of AITD as a factor that increases the risk of TC, few molecular mechanisms to support this conclusion have been described. Additionally, little information is available to explain, pathophysiologically, the effects of autoimmunity in TC diagnosis, progression, and prognosis.

High doses of metformin induces oxidative stress (OS) and transforming growth factor β1 (TGF-β1) in breast cancer cells, which was associated with increased cancer stem cell population, local invasion, liver metastasis and treatment resistance. Considering the impact of TGF- β1 and OS in breast cancer and the interrelation between these two pathways, the objective of this work was to investigate the effects of consecutive metformin treatments, at a non-cytotoxic dosage, in TGF- β1 targets in MCF-7 and MDA-MB-231 cells. Cells were exposed to 6 μM of metformin for seven consecutive passages. Samples were collected to immunocytochemistry (evaluation of p53, Nf-кB, NRF2 and TGF-β1), biochemical (determination of lipoperoxidation, total thiols and nitric oxide/peroxynitrite levels) and molecular biology analyzes (microarray and Real-time quantitative array PCR). Microarray analysis confirmed alterations in genes related to OS and TGF-β1. Treatment interfered in several TGF-β1 target-genes. Metformin upregulated genes involved in OS generation and apoptosis, and downregulated genes associated with metastasis and epithelial mesenchymal transition in MCF-7 cells. In MDA-MB-231 cells, metformin downregulated genes involved with cell invasion, viability and proliferation. The results shows that even a non-cytotoxic dosage of metformin can promote a less aggressive profile of gene expression in breast cancer cells.

Objectives This study aimed to analyze the effect of creatine (Cr) supplementation on tumor microenvironment, evaluating the parameters of tumor aggressiveness. Methods Sixteen male Wistar rats were randomly assigned to 2 groups (n = 8/group): Tumor-bearing (T) and tumor-bearing supplemented with Cr (TCr). Cr supplementation was provided in drinking water for a total of 21 d. After 11 d of Cr supplementation (TCr group) or water (T group), Walker-256 tumor cells were inoculated subcutaneously in the right flank of all rats, which kept receiving Cr supplementation (TCr group) or water (T group) for 10 more days. The total period of the experiment was 21 d. Results Tumor weight corresponded with approximately 3.5% ± 0.9% of animal body weight in the T group. Cr supplementation did not accelerate tumor growth or increase tumor size. The histopathological analysis demonstrated the presence of nuclear pleomorphisms and atypical nuclei, with the presence of low-differentiated tumor cells, in both groups. Cr supplementation did not alter apoptosis and cell proliferation markers, nor tumor capsule thickness and viable tumor area. Conclusions Cr supplementation in Walker-256 tumor-bearing rats did not induce significant changes in tumor development, and did not interfere with the parameters of tumor aggressiveness, such as the level of cell differentiation and proliferation.

Cutaneous melanoma is one of the most lethal cancers because of its increased rate of metastasis and resistance to available therapeutic options. Early studies indicate that metformin has beneficial effects on some types of cancer, including melanoma. To clarify knowledge of the mechanism of action of metformin on this disease, two treatment-based approaches are presented using metformin on melanoma progression: an in-vitro and an in-vivo model. The in-vitro assay was performed for two experimental treatment periods (24 and 48 h) at different metformin concentrations. The results showed that metformin decreased cell viability, reduced proliferation, and apoptosis was a major event 48 h after treating B16F10 cells. Oxidative stress was characterized by the decrease in total thiol antioxidants immediately following 24 h of metformin treatment and showed an increase in lipid peroxidation. The in-vivo model was performed by injecting B16F10 cells into the subcutaneous of C57/BL6 mice. Treatment with metformin began on day 3 and on day 14, the mice were killed. Treatment of mice with metformin reduced tumor growth by 54% of its original volume compared with nontreatment. The decrease in systemic vascular endothelial growth factor, restoration of antioxidants glutathione and catalase, and normal levels of lipid peroxidation indicate an improved outcome for melanoma following metformin treatment, meeting a need for new strategies in the treatment of melanoma.

Aims The main aim of this study was to investigate the moderate versus high-load resistance training on muscle strength, hypertrophy and protein synthesis signaling in rats. Methods Twenty rats were randomly allocated into three groups as follow: control group (C, n = 6), high-load training (HL, n = 7) and moderate-load training (ML, n = 7). A ladder climb exercise was used to mimic resistance exercise. ML resistance training consisted of a moderate load, allowing performance at higher volume of load inherent to higher number of repetitions (8-16 climbing). HL resistance training consisted of progressively increase training load, with low volume of load (4-8 climbing). C group remained with physical activity restricted to their cage space. This experiment was conducted over a six-weeks period. Forty-eight hours after the last resistance training session the animals were euthanized for tissue collection. Results Both HL and ML regimens promoted similar increases in muscle strength, elevated protein synthesis signaling demonstrated by increased skeletal muscle total/phosphorylated P-70S6K ratio and similar increases in plantaris and FHL muscle hypertrophy, all compared to control. All these similarities were demonstrated even though testosterone/cortisol ratio was higher in HL group compared to ML and control. ML regimen caused higher total training volume and soleus muscle hypertrophy, which was not demonstrated in HL group. Conclusion In conclusion, results suggest that both HL and ML induce muscle hypertrophy and increase on strength in a similar way. ML moreover seems to favor slow fiber hypertrophy due the higher training volume.

The incidence of skin cancers has increased worldwide, requiring more prevention of this type of cancer. The use of sunscreen and the control of the time of exposure to sunlight are the recognized forms of prevention. However, new substances have been researched in order to develop formulations with more efficient protective activity. Citral is a natural compound with lemon scent that is used in food and cosmetic industries. The present work evaluated the chemoprotective effect of citral during UVB-induced skin carcinogenesis. Male hairless mice HRS/J, 8–12 weeks old, were exposed to UVB irradiation for 24 weeks, with a cumulative radiation dose of 13.875 J/cm2. Citral (0.1, 0.5 and 1%) was applied to the skin at a dosage of 0.1 g/animal, 5 min after UVB exposure. At the end of the experiment, the number of lesion/animal, and size of lesions were measured. The histological sections of the skin were evaluated for the presence and intensity of actinic keratosis and squamous cell carcinoma. TUNEL assay was performed for apoptosis evaluation. Skin samples were used for the measurement of oxidative stress parameters (total radical-trapping antioxidant parameter of skin, glutathione, catalase activity and malondialdehyde), and cytokines levels (IL-1β, IL-4, IL-10, IL-23, TNF-α, and IFNγ). Citral 1% completely inhibited UVB-induced skin carcinogenesis by reducing levels of oxidative stress and pro-inflammatory cytokines, increasing apoptotic rate in the skin.

Muscle atrophy and strength decline are two of the most prominent characteristics in cancer patients undergoing cancer therapy, leading to decreased functional ability and reduced quality of life. Therefore, the aim is to systematically review research evidence of the effects of resistance exercise (RE) on lower-limb muscular strength, lean body mass (LBM), and body fat (BF) in cancer patients undertaking neoadjuvant or adjuvant therapy. This research was conducted using the following online database: Clinical Trial Register, Cochrane Trial Register, PubMed, SPORT Discus, and SciELO, from September 2014 until May 2015. We used the following keywords in various combinations with a systematic search: “Cancer therapy,” “Wasting muscle,” “Muscle loss,” “Muscle function,” “Neoadjuvant therapy,” “Adjuvant thera-py,” “Resistance Training,” “Weight training,” and “Exercise.” After selection of 272 full-text articles, 14 publications were included in this meta-analysis. Resistance exercise (RE) during neoadjuvant or adjuvant therapy increased lower-limb muscular strength (mean: 26.22 kg, 95% CI [16.01, 36.43], heterogeneity: P =

Aims Well-characterized animal tumor models of cancer cachexia are warranted to elucidate underlying mechanisms and provide a better approach to the human scenario. We aimed to investigate whether solid Ehrlich carcinoma reproduces clinical, functional and biological conditions of tumor-induced cachexia in mice. Methods Eight-week old female Swiss mice were subcutaneously inoculated with Ehrlich tumor cells (tumor-bearing, TB group) or vehicle (sham) into the right flank and monitored for 28 days. Tumor histopathological features and tumor–host interaction, including tissue weight, muscle structure, strength and biochemical parameters were carried out. Key findings Tumor growth curve demonstrated a linear pattern with no difference in final carcass weight between groups. A well-defined capsule composed by connective tissue infiltrated by inflammatory and neoplastic cells surrounded the tumors. The TB group had reduced handgrip strength, aside from lower cross sectional area (CSA) and critically reduced parametrial fat pads. Plasma parameters of lactate dehydrogenase (LDH), creatine kinase (CK) and tumor necrosis factor-α (TNF-α) were higher in the TB group, suggesting predominance of catabolic and pro-inflammatory activities. Conversely, food intake and tissue weight did not differ between groups. Significance Our data elucidated that the solid Ehrlich tumor model is feasible and effective in reproducing some of the relevant issues experienced by cancer patients with cachexia. The solid Ehrlich carcinoma emerges as an alternative tool against more aggressive cancer cachexia models during preclinical research.

Malignant melanoma is the most dangerous form of skin cancer. Despite new therapies for melanoma treatment, effective therapy is mainly limited by excessive metastasis. Currently, the factors determining metastasis development are not elucidated, but oxidative stress was suggested to be involved. To this end, we analyzed oxidative stress parameters during the metastatic development using the syngeneic B16F10 melanoma model. An increase in blood plasma lipid peroxidation occurred at the earliest stage of the disease, with a progressive decrease in oxidative damage and an increase in antioxidant defense. Vice versa, increased lipid peroxidation and 3-nitrotyrosine, and decreased antioxidant parameters were observed in the metastatic nodules throughout the disease. This was concomitant with a progressive increase in vascular endothelial growth factor and proliferating cell nuclear antigen. We conclude that the oxidative stress in the bloodstream decreases during the metastatic process and that nitrosative stress increases during the proliferation and growth of metastatic nodules in the tumor microenvironment. These results will help to better understand the role of oxidative stress during melanoma metastasis.

Metformin was shown to sensitize multidrug resistant breast cancer cells; however, the mechanisms involved in this capacity need to be clarified. We investigated oxidative stress and inflammatory-related pathways during the induction of doxorubicin resistance in MCF-7 and MDA-MB-231 human breast cancer cells (DOX-res group), and evaluated metformin-induced cellular responses that resulted in the prevention of doxorubicin resistance (Met-DOX group). Microarray analysis demonstrated that DOX-res changed the expression of genes involved in oxidative stress (OS) and the TGF- β1 pathway. The DOX-res group presented increased thiols and reduced lipoperoxidation, increased levels of nitric oxide, nuclear NF-kB and Nrf2, and reduced nuclear p53 labelling. Analysis of the TGF-β1 signaling pathway by RT-PCR array showed that DOX-res developed adaptive responses, such as resistance against apoptosis and OS. Metformin treatment modified gene expression related to OS and the IFN-α signaling pathway. The Met-DOX group was more sensitive to DOX-induced OS, presented lower levels of nitric oxide, nuclear NF-kB and Nrf2, and increased nuclear p53. Analysis of the IFN-α signaling pathway showed that Met-DOX presented more sensitivity to apoptosis and OS. Our findings indicate that metformin is a promising tool in the prevention of chemoresistance in patients with breast cancer submitted to doxorubicin-based treatments.

Cumulative ultraviolet (UV) exposure is associated with squamous skin cell carcinoma. UV radiation induces oxidative modifications in biomolecules of the skin leading to photocarcinogenesis. Indeed, the cyclobutene pyrimidine dimers and other dimers formed by photoaddition between carbon-carbon bonds also have an important role in the initiation process. However, information on the systemic redox status during these processes is scarce. Thus, we investigated the systemic redox profile in UVB-induced squamous cell carcinoma in mice. Female hairless mice were exposed to UVB radiation (cumulative dose = 17.1 J/cm2). The dorsal skin of these mice developed actinic keratosis (AK) and squamous cell carcinoma (SCC) and presented increased levels of oxidative and nitrosative stress biomarkers (4-hydroxy-2-nonenal and 3-nitrotyrosine), and decreased antioxidant defenses. Systemically, we observed the consumption of plasmatic antioxidant defenses and increased levels of advanced oxidized protein products (AOPP), an oxidative stress product derived from systemic inflammatory response. Taken together, our results indicate that UVB chronic irradiation leads not only to adjacent and tumoral oxidative stress in the skin, but it systemically is reflected through the blood. These new findings clarify some aspects of the pathogenesis of SCC and should assist in formulating better chemoprevention strategies, while avoiding additional primary SCC development and metastasis.

The aim of this study was to investigate the effects of creatine supplementation on muscle wasting in Walker-256 tumor-bearing rats. Wistar rats were randomly assigned into three groups (n = 10/group): control (C), tumor bearing (T), and tumor bearing supplemented with creatine (TCr). Creatine was provided in drinking water for a total of 21 days. After 11 days of supplementation, tumor cells were implanted subcutaneously into T and TCr groups. The animals’ weight, food and water intake were evaluated along the experimental protocol. After 10 days of tumor implantation (21 total), animals were euthanized for inflammatory state and skeletal muscle cross-sectional area measurements. Skeletal muscle components of ubiquitin–proteasome pathways were also evaluated using real-time PCR and immunoblotting. The results showed that creatine supplementation protected tumor-bearing rats against body weight loss and skeletal muscle atrophy. Creatine intake promoted lower levels of plasma TNF-α and IL-6 and smaller spleen morphology changes such as reduced size of white pulp and lymphoid follicle compared to tumor-bearing rats. In addition, creatine prevented increased levels of skeletal muscle Atrogin-1 and MuRF-1, key regulators of muscle atrophy. Creatine supplementation prevents skeletal muscle atrophy by attenuating tumor-induced pro-inflammatory environment, a condition that minimizes Atrogin-1 and MuRF-1-dependent proteolysis.

Meta-analyses have shown that supervised isometric handgrip training reduces blood pressure in hypertensives. However, the mechanism(s) underlying these effects in medicated hypertensive patients, as well as the effects from home-based exercise training, is uncertain. The purpose of this study was to compare the effects of supervised and home-based isometric handgrip training on cardiovascular parameters in medicated hypertensives. In this randomized controlled trial, 72 hypertensive individuals (38–79 years old, 70% female) were randomly assigned to three groups: home-based, supervised isometric handgrip training or control groups. Home-based and supervised isometric handgrip training was completed thrice weekly (4 × 2 min at 30% of maximal voluntary contraction, with 1-min rest between bouts, alternating the hands). Before and after 12 weeks brachial, central and ambulatory blood pressures (BP), arterial stiffness, heart rate variability, vascular function, oxidative stress and inflammation markers were obtained. No significant (p > 0.05) effect was observed for ambulatory BP, arterial stiffness, heart rate variability, vascular function and oxidative stress and inflammatory markers in all three groups. Brachial BP decreased in the supervised group (Systolic: 132 ± 4 vs. 120 ± 3 mmHg; Diastolic: 71 ± 2 vs. 66 ± 2 mmHg, p < 0.05), whereas no significant differences were observed in the home-based (Systolic: 130 ± 4 vs. 126 ± 3 mmHg; diastolic: 73 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). Supervised handgrip exercise also reduced central BP systolic (120 ± 5 vs. 109 ± 5 mmHg), diastolic (73 ± 2 vs. 67 ± 2 mmHg); and mean BP (93 ± 3 vs. 84 ± 3 mmHg), whereas no significant effects were found in the home-based (Systolic: 119 ± 4 vs. 115 ± 3 mmHg; Diastolic: 74 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). In conclusion, supervised, but not home-based, isometric training lowered brachial and central BP in hypertensives.

TGF-β1 and oxidative stress are involved in cancer progression, but in melanoma, their role is still controversial. Our aim was to correlate plasma TGF-β1 levels and systemic oxidative stress biomarkers in patients with melanoma, with or without disease metastasis, to understand their participation in melanoma progression. Thirty patients were recruited for melanoma surveillance, together with 30 healthy volunteers. Patients were divided into two groups: Non-metastasis, comprising patients with tumor removal and no metastatic episode for 3 years; and Metastasis, comprising patients with a metastatic episode. The plasmatic cytokines TGF-β1, IL-1 β, and TNF-α were analyzed by ELISA. For oxidative stress, the following assays were performed: malondialdehyde (MDA), advanced oxidation protein products (AOPP) levels, total radical-trapping antioxidant parameter (TRAP) and thiol in plasma, and lipid peroxidation, SOD and catalase activity and GSH in erythrocytes. Patients with a metastatic episode had less circulating TGF-β1 and increased TRAP, thiol, AOPP and lipid peroxidation levels. MDA was increased in both melanoma groups, while catalase, GSH, and IL-1β was decreased in Non-metastasis patients. Significant negative correlations were observed between TGF-β1 levels and systemic MDA, and TGF-β1 levels and systemic AOPP, while a positive correlation was observed between TGF-β1 levels and erythrocyte GSH. Lower levels of TGF-β1 were related to increased oxidative stress in Metastasis patients, reinforcing new evidence that in melanoma TGF-β1 acts as a tumor suppressor, inhibiting tumor relapse. These findings provide new knowledge concerning this cancer pathophysiology, extending the possibilities of investigating new therapies based on this evidence.

The participation of oxidative stress in the mechanism of metformin action in breast cancer remains unclear. We investigated the effects of clinical (6 and 30 μM) and experimental concentrations of metformin (1000 and 5000 μM) in MCF-7 and in MDA-MB-231 cells, verifying cytotoxicity, oxidative stress, DNA damage, and intracellular pathways related to cell growth and survival after 24 h of drug exposure. Clinical concentrations of metformin decreased metabolic activity of MCF-7 cells in the MTT assay, which showed increased oxidative stress and DNA damage, although cell death and impairment in the proliferative capacity were observed only at higher concentrations. The reduction in metabolic activity and proliferation in MDA-MB-231 cells was present only at experimental concentrations after 24 h of drug exposition. Oxidative stress and DNA damage were induced in this cell line at experimental concentrations. The drug decreased cytoplasmic extracellular signal-regulated kinases 1 and 2 (ERK1/2) and AKT and increased nuclear p53 and cytoplasmic transforming growth factor β1 (TGF-β1) in both cell lines. These findings suggest that metformin reduces cell survival by increasing reactive oxygen species, which induce DNA damage and apoptosis. A relationship between the increase in TGF-β1 and p53 levels and the decrease in ERK1/2 and AKT was also observed. These findings suggest the mechanism of action of metformin in both breast cancer cell lineages, whereas cell line specific undergoes redox changes in the cells in which proliferation and survival signaling are modified. Taken together, these results highlight the potential clinical utility of metformin as an adjuvant during the treatment of luminal and triple-negative breast cancer.

Citral is a natural compound that has shown cytotoxic and antiproliferative effects on breast and hematopoietic cancer cells; however, there are few studies on melanoma cells. Oxidative stress is known to be involved in all stages of melanoma development and is able to modulate intracellular pathways related to cellular proliferation and death. In this study, we hypothesize that citral exerts its cytotoxic effect on melanoma cells by the modulation of cellular oxidative status and/or intracellular signaling. To test this hypothesis, we investigated the antiproliferative and cytotoxic effects of citral on B16F10 murine melanoma cells evaluating its effects on cellular oxidative stress, DNA damage, cell death, and important signaling pathways, as these pathways, namely, extracellular signal-regulated kinases 1/2 (ERK1/2), AKT, and phosphatidylinositol-3 kinase, are involved in cell proliferation and differentiation. The p53 and nuclear factor kappa B were also investigated due to their ability to respond to intracellular stress. We observed that citral exerted antiproliferative and cytotoxic effects in B16F10; induced oxidative stress, DNA lesions, and p53 nuclear translocation; and reduced nitric oxide levels and nuclear factor kappa B, ERK1/2, and AKT. To investigate citral specificity, we used non-neoplastic human and murine cells, HaCaT (human skin keratinocytes) and NIH-3T3 cells (murine fibroblasts), and observed that although citral effects were not specific for cancer cells, non-neoplastic cells were more resistant to citral than B16F10. These findings highlight the potential clinical utility of citral in melanoma, with a mechanism of action involving the oxidative stress generation, nitric oxide depletion, and interference in signaling pathways related to cell proliferation.

The role of reactive oxygen species (ROS) in muscle protein hydrolysis and protein oxidation in thyrotoxicosis has not been explored. This study indicates that ROS play a role in skeletal muscle wasting pathways in thyrotoxicosis. Two experimental groups (rats) were treated for 5 days with either 3,3',5-triiodothyronine (HT) or HT with α-tocopherol (HT + αT). Two controls were used, vehicle (Control) and control treated with αT (Control + αT). Serum T3, peritoneal fat, serum glycerol, muscle and body weight, temperature, mitochondrial metabolism (cytochrome c oxidase activity), oxidative stress parameters and proteolytic activities were examined. High body temperature induced by HT returned to normal when animals were treated with αT, although total body and muscle weight did not. An increase in lipolysis was observed in the HT + αT group, as peritoneal fat decreased significantly together with an increase in serum glycerol. GSH, GSSG and total radical-trapping antioxidant parameter (TRAP) decreased and catalase activity increased in the HT group. The glutathione redox ratio was higher in HT + αT than in both HT and Control + αT groups. Carbonyl proteins, AOPP, mitochondrial and chymotrypsin-like proteolytic activities were higher in the HT group than in the Control. HT treatment with αT restored mitochondrial metabolism, TRAP, carbonyl protein, chymotrypsin-like activity and AOPP to the level as that of the Control + αT. Calpain activity was lower in the HT + αT group than in HT and Control + αT and superoxide dismutase (SOD) activity was higher in the HT + αT group than in the Control + αT. Although αT did not reverse muscle loss, ROS was involved in proteolysis to some degree.

This article presents a general discussion about the participation of oxidative stress in relevant points related to breast cancer progression in vitro. All of the evidences presented here are based on published papers that used breast cancer cells with different phenotype characteristics in their research. We observed that oxidative stress could modulate by several manners the tumor progression and these effects are directly related to its concentration and time of cell exposure to these substances. Furthermore, oxidative stress produced and released by breast cancer cells is able to interfere in the metabolism of the adjacent normal cells in a manner that improve the survival of the neoplastic cells. In relation to breast cancer treatment, the role of oxidative stress is complex. At the same time that it can be responsible to the induction of cell death, oxidative stress can also modulate pathway that leads to increased expression of anti-apoptotic and resistance-related proteins. Therefore, the participation of oxidative stress in breast cancer is complex and very broad and its better understanding could be important to the development of more effective therapeutic strategies for the different forms clinically found of the disease.

Introduction We sought to verify whether isoflavin-beta (Iso-β), a mixture of isoflavones with antioxidant properties, could prevent thyrotoxicosis-induced loss of muscle mass and the participation of oxidative stress (OS) in the mechanisms of this prevention. Methods Two experimental periods of thyrotoxicosis induction were used in Wistar rats: 3 and 5 days to assess Iso-β effects before and after thyrotoxicosis-induced muscle wasting. After euthanasia, peritoneal fat and gastrocnemius muscle were collected, weighed, and muscle OS was assessed. Results Iso-β prevented the loss of gastrocnemius mass in thyrotoxic rats through the prevention of muscle OS generation during thyrotoxicosis, increasing muscle total antioxidant capacity and decreasing mitochondrial cytochrome c oxidase activity, lipid peroxidation, and protein carbonyl content. Conclusion Iso-β decreased oxidative modification of proteins, which is known to exert a major role during proteolysis induction and is present in thyrotoxic myopathy, highlighting the potential action of Iso-β in this complication of the disease. Muscle Nerve 56: 975–981, 2017

The WT1 gene encodes a transcription factor involved in regulation of many cellular processes, including proliferation, differentiation, mRNA processing and apoptosis, besides acting as a transcription repressor of growth factors and their receptors' genes. This gene is expressed at high levels in several types of cancers, including acute leukemias. In this regard, many studies have identified WT1 protein as a tumor antigen, considered a target molecule for clinical application in human acute leukemias. Immunotherapy using WT1 antigen has been effective in stimulating immune responses against leukemic cells. Regarding adoptive immunotherapy, the use of dendritic cells (DCs) for the WT1-specific cytotoxic T cells generation proved to be efficient in the development and maintenance of immunologic cells. Therefore, these therapeutic methods, that provided enthusiasm for moving ahead, highlight several opportunities and challenges to be used in clinical practice for managing acute leukemias.

O câncer de mama é o segundo tipo de neoplasia mais frequente entre as mulheres no mundo todo. A metformina é uma droga antihiperglicemiante segura e eficaz, amplamente utilizada no tratamento do diabetes tipo 2. Nos últimos anos, o seu uso tem sido associado a menor incidência de câncer e, por esses motivos, os seus efeitos na proliferação de células de câncer de mama e na sensibilização dessas células ao tratamento têm sido investigados. Pesquisas recentes demonstram que a metformina reduz a proliferação de células de câncer de mama sensíveis e é capaz de ressensibilizar células com múltipla resistência a drogas. Entretanto, os mecanismos de ação da metformina ainda não foram totalmente esclarecidos, e a sua capacidade de sensibilizar as células tumorais ao tratamento nunca foi descrita. Portanto, o objetivo desse trabalho foi investigar a participação do estresse oxidativo (EO) nos mecanismos de citotoxicidade da metformina em células de adenocarcinoma mamário humano positivas para receptores hormonais e triplo negativas, MCF-7 e MDA-MB- 231, respectivamente, e investigar os efeitos da metformina no processo de indução experimental de resistência à doxorrubicina. Para a análise da participação do EO nos mecanismos de citotoxicidade da droga, avaliou-se o padrão de morte celular, a presença de danos oxidativo ao DNA, parâmetros de estresse oxidativo e efeito da metformina sobre algumas proteínas de sinalização importantes no controle do crescimento e proliferação celular (ERK1/2, AKT, TGF − β1 e p53). Para isso, quatro concentrações diferentes da droga foram utilizadas: duas clinicamente relevantes, que correspondem às concentrações plasmáticas encontradas em indivíduos após tratamento (6 e 30 μM), e duas experimentais (1000 e 5000 μM). Para a investigação dos efeitos da metformina no processo de indução de resistência à doxorrubicina, as células foram expostas a concentrações crescentes do quimioterápico e a metformina foi associada em diferentes momentos, simultaneamente e através de um prétratamento. Foram analisados o estado oxidativo celular ao longo do processo de indução da quimiorresistência, os níveis de óxido nítrico (NO) e os efeitos da droga em vias que poderiam relacionar-se com a quimiorresistência, como a p53, NF-kB, Nrf2 e TGF-β1. Com base nos primeiros resultados (em células sensíveis), escolhemos uma concentração de metformina que identificamos como não citotóxica (6 μM) para ser estudada no modelo de indução de resistência à doxorrubicina. Os resultados demonstraram que a metformina, nas células de câncer de mama sensíveis, é citotóxica a partir de concentrações clinicamente relevantes (30 μM) e que esse efeito ocorre através da indução simultânea de estresse oxidativo, dano de DNA e aumento dos níveis citoplasmáticos de TGF-β1. Além disso, a droga, em concentrações mais elevadas (1000 e 5000 μM), induz apoptose celular, diminui a ERK1/2 e a Akt (5000 μM), e aumenta os níveis nucleares de p53 (1000 e 5000 μM). No processo de indução de quimiorresistência, o pré-tratamento com metformina preveniu a resistência à doxorrubicina nas duas linhagens celulares estudadas, além de sensibilizar as células MCF-7 ao quimioterápico. Essa prevenção ocorreu através da geração de estresse oxidativo, redução nos níveis de NO, aumento de p53 nuclear e de TGF-β1 citoplasmático, e redução de Nrf2 nuclear. Esses resultados ajudam a entender os mecanismos de ação da metformina em células MCF-7 e MDA-MB-231 e sugerem que o tratamento com a droga pode exercer efeito benéfico na prevenção da resistência à doxorrubicina, ressaltando a potencial utilidade clínica da metformina como adjuvante na terapia do câncer de mama. Breast cancer is the second type of the most frequent neoplasia among women worldwide. Metformin is a safe and effective anti-hyperglycemic drug widely used in the treatment of type 2 diabetes. In the last years, its use has been associated with a lower cancer incidence and, for these reasons, their effects on breast cancer cells proliferation and in the sensitization of these cells to treatment have been investigated. Current research demonstrated that metformin reduces proliferation of breast cancer cells and sensitize multidrug resistance cells. However, the metformin mechanisms of action has not yet been fully elucidated, and its interference with the process of chemoresistance induction has never been described. Therefore, the objective of this study was to investigate the involvement of oxidative stress (OS) in the mechanism of metformin cytotoxicity in human mammary adenocarcinoma cells positive for hormone receptors and triple negative, MCF-7 and MDA-MB-231, respectively, and investigate the metformin effects in the process of experimental doxorubicin resistance induction. For the analysis of the participation of OS in the mechanisms of drug cytotoxicity, it was evaluated the cell death pattern, the presence of oxidative DNA lesions, oxidative stress parameters and the drug effect on some important signaling proteins involved in the control of cell growth and proliferation, such as ERK1/2, AKT, TGF - β1 and p53. Four different concentrations of metformin were used: two clinically relevant, corresponding to plasmatic concentrations found in patients after diabetes treatment (6 e 30 μM), and two experimental (1000 and 5000 μM). For the investigation of metformin participation in the process of chemoresistance induction, the cells were exposed to increasing concentrations of the chemotherapic and metformin was associated at different times, simultaneously and through a pretreatment. It was evaluated the cellular oxidative status during the process of chemoresistance induction, the nitric oxide (NO) levels and the drug effects on pathways that could be related to chemoresistance, such as p53, NF-kB, Nrf2 and TGF-β1. Based on the first results (in sensitive cells), we chose a non-cytotoxic metformin concentration (6 μM) to be studied in the model of doxorubicin resistance induction. The results demonstrated that metformin is cytotoxic to tumor cells from clinically relevant concentrations (30 μM) and that this effect occurs by the simultaneous induction of oxidative stress, DNA damage and increase in cytoplasmic TGF-β1. In addition, at higher concentrations, the drug induces apoptosis (1000 and 5000 μM), reduces the ERK1 / 2 and Akt (5000 μM), and increases nuclear p53 (1000 and 5000 μM). In the process of chemoresistance induction, metformin pretreatment prevented the doxorubicin resistance in both cell lines, as well as sensitize MCF-7 cells to chemotherapy. This prevention occurred by the generation of oxidative stress, reduction in the NO levels, increases in nuclear p53 and cytoplasmic TGF-β1, and reduction of nuclear Nrf2. These findings helps to understand the metformin mechanism of action on MCF-7 and in MDA-MB-231 breast cancer cells and suggests that metformin treatment could exert a beneficial role in the prevention of doxorubicin chemoresistance, highlighting the potential clinical utility of metformin as adjuvant during breast cancer treatment.

Toxoplasmosis is an infection caused by the protozoan Toxoplasma gondii and is a serious publichealth problem that can be fatal in immunocompromised individuals or congenital infections.Congenital toxoplasmosis disease results from transplacental parasite transfer to the fetus duringchildbirth or primary infection of the mother or acute relapse. The clinical manifestations aredifferent for neonates, with potentially fatal or debilitating consequences that primarily affect thecentral nervous system and/or generate ocular involvement. Depending on the gestational stage,the current treatment of congenital toxoplasmosis is limited to the use of spiramycin or, in fetalinfection, supported by the combination of pyrimethamine and sulfadiazine associated with folinicacid. However, these regimens may be toxic to the embryo/fetus. Therefore, research has examinedalternative therapies for this infection and thus the aim of this manuscript was to review the mainstudies involving different compounds as potential treatments for congenital toxoplasmosis. Amongthe compounds most frequently cited in the literature as an alternative therapy for congenitaltoxoplasmosis, were artemisinin, atovaquone, azithromycin and diclazuril. It was observed thatartemisinin and atovaquone may have teratogenic dose-dependent effects. Already azithromycinand diclazuril have shown promising results when used in murine models or cell culture, but theireffectiveness has not been fully confirmed in humans. The compounds mentioned here, despite stillbeing in experimental and clinical trials, add new data and perspectives for the treatment of infection.

Cardiac cachexia is a syndrome that has received increased attention in recent years. Although an association between proteolysis and cardiac cachexia has been proposed, the direct influence of oxidative stress on the process has not been demonstrated. In the present study, the right (RH) and left (LH) hearts (atrium and ventricle of each side of the heart) were collected from rats at the 5th and 10th days after phosphate buffer (control) orWalker-256 solid tumour implantation. Immediately after sacrifice, cachexia was determined in tumour-bearing animals by the formula: [(inicial body weight-final body weight+tumour weight+weight gain of control group)/(initial body weight+body mass gain of control group)]×100%; RH and LH were stored until use. Oxidative stress and proteolysis were determined in each collected sample. In addition, heart samples were collected from a separate set of animals to determine the thickness of the left and right ventricles. Cachexia values increased over time after tumour implantation from 6.85% at the 5th day to 17.76% at the 10th day. There was no significant difference in LH wet weight and ventricle thickness compared with the control, where as RH wet weight (0.109±0.09g at the 5th day and 0.093±0.09g at the 10th day) and thickness (420±16μm at the 5th day and 279±08μm at the 10th day) were significantly decreased at both time points when compared with control values (0.153±0.06g and 607±21μm, respectively). tert-Butyl-stimulated chemiluminescence analysis revealed a significant increase in the LH and decrease in the RH oxidative stress profiles. Carbonylated proteins increased in the LH (140%, p0.05) and RH (100%, p0.05) at the 5th day, and significantly decreased in both sides on the 10th day compared to controls. Chemotrypsin-like, caspase-like, and calpain-like activities were evaluated by chemiluminescence, and only calpain-like activity was found to increase at the 5th day in the RH. In the LH, all proteolytic activities systems were decreased when compared with controls. Together, these results demonstrate that oxidative stress appears to play a different role in mass modulation on the LH and RH. The proteolytic systems evaluated herein also appear to have different effects on the responses developed during cardiac cachexia in the two sides of the heart.

O termo neoplasia de cabeça e pescoço faz referência a um conjunto de tumores benignos ou malignos, localizados anatomicamente no trato aerodigestivo superior. Podem surgir em vários locais como nas mucosas da boca em regiões como lábios, base da língua, língua, assoalho bucal e palato duro, e na faringe em regiões como orofaringe, hipofaringe e nasofaringe. Em grande parte das situações, a distinção entre tumores benignos e malignos é baseada em aspectos morfológicos. Entretanto, em determinadas situações não existe concordância entre os aspectos do tumor com seu comportamento biológico dificultando o diagnóstico correto. Sabendo do envolvimento do estresse oxidativo no desenvolvimento de vários tipos de neoplasias, o objetivo desse trabalho foi determinar os parâmetros de estresse oxidativo sistêmico em pacientes com alterações benignas e malignas em cabeça e pescoço. Após aprovação pelo conselho de ética, (CEP-UEL nº 3.595.210), foram incluídos 35 indivíduos saudáveis de um banco de dados em nosso laboratório, formando o grupo controle (n=35). No grupo experimental, foram coletadas amostras de sangue de 40 pacientes com lesões benignas e malignas em região de cabeça e pescoço, que foram divididos em dois grupos: BENIGNO (n=9) e CECP (n=31). As amostras de sangue coletadas foram utilizadas para avaliação de parâmetros de estresse oxidativo sistêmico. Um questionário para avaliação de dados clínicos patológicos também foi coletado. Quanto às análises de estresse oxidativo sistêmico, foram avaliados nos eritrócitos a defesa antioxidante mediados pela Superóxido Dismutase (SOD), Catalase (CAT) e Glutationa Reduzida (GSH), além da lipoperoxidação de membrana. Os resultados para SOD e CAT mostraram que a atividade dessas enzimas foi maior em relação ao grupo controle. Na análise da GSH, somente o grupo CECP apresentou níveis significativamente reduzidos em relação ao controle. Quando o grupo BENIGNO foi comparado ao CECP nenhuma diferença significativa foi encontrada para os parâmetros citados. Além disso a capacidade conter a lipoperoxidação foi significativamente menor no grupo BENIGNO e CECP. Quando comparado entre si, não foram observadas diferenças relevantes. Pelas análises realizadas, o estresse oxidativo a nível sistêmico foi mais pronunciado em pacientes com neoplasias benignas e malignas em relação ao grupo controle. A análise comparativa entre os grupos não mostrou diferenças estatisticamente relevantes nos marcadores de estresse utilizados neste estudo, o que indica e justifica um aumento do estudo dos tipos de marcadores para estresse oxidativo em neoplasias de cabeça e pescoço. The term head and neck neoplasm refers to a set of benign or malignant tumors, anatomically in the upper aerodigestive tract. They can appear in various places, such as in the mouth mucosa in regions such as the lips, base of the tongue, tongue, mouth floor and hard palate, and in the pharynx in regions such as the oropharynx, hypopharynx and nasopharynx. In most of the hypotheses, the distinction between benign and malignant tumors is based on morphological aspects. However, in certain hypotheses there is no agreement between the aspects of the tumor and its biological behavior, making the correct diagnosis difficult. Knowing the involvement of oxidative stress in the development of various types of neoplasms, the aim of this study was to determine the parameters of systemic oxidative stress in patients with benign and malignant changes in the head and neck. After approval by the ethics board (CEP-UEL nº 3.595.210), 35 included were included, included in a database in our laboratory, forming the control group (n = 35). In no experimental group, blood was collected from 40 patients with benign and malignant lesions in the head and neck region, which were divided into two groups: BENIGNO (n = 9) and CECP (n = 31). Blood collections were used to assess systemic oxidative stress parameters. A questionnaire for evaluating clinical pathological data was also collected. As for the analysis of systemic oxidative stress, the antioxidant defense mediated by Superoxide Dismutase (SOD), Catalase (CAT) and Reduced Glutathione (GSH) were taken in erythrocytes, in addition to membrane lipoperoxidation. The results for SOD and CAT impartial that the activity of these enzymes was higher compared to the control group. In the analysis of GSH, only the CECP group presented reduced levels in relation to the control. When the BENIGNO group was compared to CECP, no defined difference was found for the mentioned parameters. Furthermore, the ability to contain lipoperoxidation was less compliant in the BENIGNO and CECP groups. When compared to each other, they were not observed relevant. Based on the analyzes performed, systemic oxidative stress is more pronounced in patients with benign and malignant neoplasms compared to the control group. A comparative analysis between groups not statistically differentiated regarding the stress markers used in this study, which indicates and justifies an increase in the study of the types of markers for oxidative stress in head and neck neoplasms.

O câncer colorretal (CCR) é uma neoplasia maligna que ocorre no intestino grosso, mais frequentemente nas regiões do cólon e do reto. É o terceiro tipo de câncer com maior incidência entre homens e o segundo entre mulheres. O tipo mais comum de CCR é o adenocarcinoma, responsável por 96% dos tipos de câncer colorretal. O adenocarcinoma é geralmente estabelecido a partir de pólipos adenomatosos que sofrem alterações displásicas, resultando em células malignas. Quando se tem metástase, o prognóstico é pior, pois é a principal causa de morte, neste caso a neoplasia é classificada como estágio IV, de uma classificação que vai de I a IV, de acordo com as características estabelecidas para o diagnóstico. Embora a literatura correlacione fortemente o CCR com a inflamação, ainda é escassa a relação do estresse oxidativo (EO) sistêmico desencadeado pelo processo inflamatório crônico nos pacientes com a doença, bem como a relação com o estágio clínico. Nosso trabalho tem como objetivo avaliar o perfil de estresse oxidativo e perfil inflamatório sistêmico de pacientes com câncer colorretal, correlacionando com parâmetros clínicos e com o estadiamento da doença. Foram avaliadas amostras de 36 pacientes com CCR em fase de quimioterapia e 24 pacientes saudáveis. Para os parâmetros de EO foram avaliados antioxidantes enzimáticos como catalase, superóxido dismutase e não enzimáticos como glutationa e outros marcadores de EO como malondialdeído, produto de proteínas oxidadas e lipoperoxidação de membrana. Além dos parâmetros pró e anti-inflamatórios (IL-2, IL-4, IL-6, IL-10, TNFα e INF-y). Fizemos uma correlação entre os parâmetros inflamatórios e de EO a fim de elucidar melhor a relação. Nossos resultados indicam que com menos agentes de oxidação (malondialdeído) e mais antioxidantes (catalase), além de um aumento na citocina imunossupressora (IL-10), a carcinogênese colorretal pode estabelecer um ambiente sistêmico propício à sua progressão e, consequentemente, favorecimento de metástase. Colorectal cancer (CRC) is a malignant neoplasm that occurs in the large intestine, most often in the colon and rectum regions. It is the third type of cancer with the highest incidence among men and the second among women. The most common type of CRC is adenocarcinoma, responsible for 96% of the types of colorectal cancer. Adenocarcinoma is generally established from adenomatous polyps that undergo dysplastic changes, resulting in malignant cells. When there is metastasis, the prognosis is worse, as it is the main cause of death, in this case the neoplasm is classified as stage IV, from a classification ranging from I to IV, according to the characteristics established for the diagnosis. Although the literature strongly correlates CRC with inflammation, the relationship between systemic oxidative stress (OS) triggered by the chronic inflammatory process in patients with the disease is still scarce, as well as the relationship with the clinical stage. Our work aims to evaluate the oxidative stress profile and systemic inflammatory profile of patients with colorectal cancer, correlating with clinical parameters and disease staging. Samples from 36 patients with CRC undergoing chemotherapy and 24 healthy patients were evaluated. For OS parameters, enzymatic antioxidants such as catalase, superoxide dismutase and non-enzymatic antioxidants such as glutathione and other OS markers such as malondialdehyde, product of oxidized proteins and membrane lipoperoxidation were evaluated. In addition to the pro and anti inflammatory parameters (IL-2, IL-4, IL-6, IL-10, TNFα and INF-y). We made a correlation between inflammatory and OS parameters in order to better elucidate the relationship. Our results indicate that with less oxidizing agents (malondialdehyde) and more antioxidants (catalase), in addition to an increase in immunosuppressive cytokine (IL 10), colorectal carcinogenesis can establish a systemic environment conducive to its progression and, consequently, favoring metastasis.

Com as mudanças dos hábitos alimentares e o envelhecimento da população, um notável aumento na incidência de câncer é observado em todo o mundo, surgindo a necessidade cada vez mais precoce de identificar fatores de risco populacionais visando a elaboração de programas de prevenção. O câncer é uma doença multifatorial que apresenta vários fatores de risco. Estes fatores variam conforme o tipo de câncer, mas de uma maneira geral os que mais se destacam são: obesidade, alcoolismo, tabagismo, exposição solar e hábitos alimentares. O objetivo principal deste trabalho foi identificar os principais fatores de risco para o câncer em uma população universitária jovem, e apontar os fatores que necessitam de campanhas de conscientização. A pesquisa foi realizada por meio do estudo transversal exploratório descritivo com a participação de 502 estudantes de graduação da Universidade Estadual de Londrina (entre 18 a 24 anos de idade). A identificação de fatores de risco foi realizada por meio de aplicação de questionário que abordou questões como vacinação e uso de preservativo, exposição solar, estilo de vida e hábito alimentar. O questionário foi respondido de forma anônima pelos graduandos das áreas de Biológicas, Exatas, Humanas, Saúde, vinculados a todos os Centros de estudo da UEL. A análise estatística foi dividida em variáveis categóricas que foram analisadas pelo teste de qui-quadrado (?2) ou teste exato de Fisher, e variáveis contínuas pelos testes de Shapiro Wilk e Levene, respectivamente, portanto, foram utilizados testes paramétricos (one way-ANOVA com post-test de Tukey), calculadas a partir do software SPSS®. Para identificar as diferenças estatísticas entre as variáveis sexo e área de conhecimento foi adotada significância estatística de p 24,9) e 26,6% de obesidade (ICM>29,9). A origem dos alimentos que consomem é predominantemente advinda de mercado e sacolão com 94,4%, e o consumo e preparação é principalmente realizada em casa (63,3%). Em relação ao conhecimento sobre os fatores de risco para câncer, 89,2% relataram já saber da relação, sendo que a maior fonte de informação relatada foi mídias digitais e internet (30,6%). Quanto às comparações estatísticas, foi possível observar que as mulheres apresentam maior conhecimento dos fatores de risco, fazem mais uso de protetor solar, consomem mais frutas in natura, vegetais crus, crucífera, chá verde ou café, consomem menos refrigerantes a base de cola e alimentos embutidos (p=0,046), além de relatarem menor consumo de tabaco. As mulheres relataram menor frequência de uso de preservativo (p 24.9) and 26.6% of obesity (BMI> 29.9). The origin of the food they consume is predominantly from the market and slaughterhouse with 94.4%, and consumption and preparation is mainly performed at home (63.3%). Regarding knowledge about cancer risk factors, 89.2% reported already knowing about the relationship, and the largest source of information reported was digital media and internet (30.6%). Regarding the statistical comparisons, it was possible to observe that women are more aware of the risk factors, use more sunscreen, consume more fresh fruits, raw vegetables, crucífera, green tea or coffee, consume less cola and (p = 0.046), in addition to reporting lower tobacco consumption. The women reported a lower frequency of condom use (p

As radiações ultravioletas (UV) são as principais responsáveis pelo desenvolvimento de lesões pré-malignas e malignas cutâneas. As duas principais radiações que atingem a superfície terrestre, responsáveis por danos ao DNA, são do tipo UVA (315 - 400nm) e UVB (280 – 315nm). Esta última induz a um ambiente pró-inflamatório quando da exposição aguda e imunossupressor quando crônico. Esta ambiguidade de evento a longo prazo induz ao tipo mais incidente de câncer, o de pele. A irradiação UVB atinge principalmente a camada epidérmica da pele, apresentando dois principais mecanismos de dano. Dano de maneira direta através da formação de dímeros de pirimidina, e a indireta, através de danos oxidativos, que se relacionam por produzir um microambiente inflamatório com oxidação de lipídeos, proteínas e mutação gênica. A imunossupressão também faz parte deste quadro caracterizando, assim, a fotocarcinogênese. Apesar da pele possuir um sistema antioxidante eficiente que controla, em parte, o excesso de espécies reativas de oxigênio produzida pela irradiação, a procura por substâncias que reduzam os efeitos danosos da UVB na pele tem sido intensa. Dentre as substâncias tem-se a selenocisteína, N-acetil-cisteína, metformina. A vitamina E, uma das mais estudadas até o momento, busca reduzir os efeitos oxidativos e imunossupressores causados pela irradiação. A metformina, um medicamento vastamente utilizado no tratamento do diabetes do tipo 2, mostrou diminuir a incidência de câncer de mama em mulheres diabéticas que fazem o seu uso. Entretanto, outros estudos conduzidos em pacientes com outros tipos de câncer não encontram a mesma resposta. Em virtude da pouca informação sobre os possíveis mecanismos envolvidos na redução da proliferação celular ou mesmo inibição do desenvolvimento do câncer quando do uso da metformina, o objetivo do presente trabalho foi trazer novas informações sobre os mecanismos desta droga sobre os efeitos inflamatórios, imunológicos e oxidativos causados pela irradiação UVB. Foi utilizado o modelo experimental murino com irradiação aguda UVB (400mJ/cm2) pré-tratado com metformina (90mg/Kg via i.p) por 11 dias. Os grupos foram divididos em: tratados com tampão fosfato salina (C+PBS); pré-tratados com metformina (C+MET); irradiado tratado com PBS (IRR+PBS); e irradiado pré-tratado com metformina (IRR+MET). Após 24h da irradiação o sangue e a pele foram removidos, o perfil redox e a quantificação de algumas citocinas epidérmicas imunomodulatórias foram quantificados. A epiderme foi separada da derme onde foram analisados a atividade metabólica mitocondrial, os níveis de ânion radical superóxido e a quantidade de células de Langerhans. Dentro das análises oxidativas sistêmicas, o malondialdeído (MDA) apresentou-se elevado (p

O câncer de mama é a neoplasia com a maior incidência e mortalidade entre as mulheres no mundo todo. Apesar de novas formas de tratamento para este tipo de câncer, o desenvolvimento de resistência ao tratamento ainda é uma grande preocupação. A metformina, um fármaco de utilização oral para o tratamento de diabetes tipo 2, vem apresentando resultados interessantes ao ser utilizado como uma possível alternativa para o tratamento de vários tipos de câncer, inclusive o câncer de mama, onde estudos mostram que a metformina induz a morte das células tumorais pela geração de estresse oxidativo. Dessa forma, o objetivo deste trabalho foi analisar por quais vias a metformina estaria induzindo a morte das células de câncer de mama humano MCF-7, utilizando os inibidores específicos para cada via de morte, como o Z-vad, um inibidor de pan-caspases, que age no sítio catalítico das caspases bloqueando a apoptose; o inibidor de necroptose, a Necrostatina-1 que age bloqueando a RIPK1, impedindo a morte por necroptose, e a Deferoxamina, um quelante de ferro que inibe a morte por ferroptose. Para isso, as células foram tratadas com duas concentrações de metformina (1mM e 5mM) concomitantemente com os inibidores de morte, Z-vad (10µM), Necrostatina-1 (50 µM) e Deferoxamina (100 µM). Após 24 horas de tratamento, foram analisados a viabilidade e proliferação celular, análise de morte celular por citometria de fluxo através da coloração com Anexina V e Iodeto de propidio, e quanto aos parâmetros de estresse oxidativo foram analisados tiol total, GSH, GSSG e malondialdeído. Os resultados mostraram que após o tratamento com as duas concentrações de metformina houve uma redução da viabilidade e proliferação das células, porém quanto ao tratamento concomitante da metformina com os inibidores, estes índices foram restaurados. Quanto aos parâmetros de estresse oxidativo, a metformina reduziu os níveis de antioxidantes (Tiol, GSH e GSSG), porém no tratamento concomitante com os inibidores de morte os antioxidantes foram preservados. Em relação ao marcador de lipoperoxidação, malondialdeído, as duas concentrações de metformina foram capazes de aumentar a sua concentração. Estes resultados nos sugerem que a metformina não induz apenas um tipo de morte celular, uma vez que os três inibidores de morte utilizados foram capazes de reverter os efeitos tóxicos do fármaco. Quanto à geração de estresse oxidativo, o tratamento com os inibidores de morte parecem proteger as células da morte induzida pela metformina, condizendo com os resultados já descritos de que a morte induzida pela metformina estaria associada com a geração de estresse oxidativo. Breast cancer is the neoplasia with the highest incidence and mortality among women worldwide. Despite new forms of treatment for this type of cancer, the development of resistance to treatment is still a major concern. Metformin, a drug of oral use for the treatment of type 2 diabetes, has been showing interesting results when used as a possible alternative for the treatment of several types of cancer, including breast cancer, where studies show that metformin induces death of the tumor cells by the generation of oxidative stress. Thus, the aim of this study was to analyze by which pathways metformin would be inducing death of human MCF-7 breast cancer cells, using specific inhibitors for each pathway of death, such as Z-vad, a pan-caspases, which acts at the catalytic site of caspases blocking apoptosis; The necrosis inhibitor, Necrostatin-1 which acts by blocking RIPK1, preventing death by necroptosis, and Deferoxamine, an iron chelator that inhibits death by ferroptosis. For this, the cells were treated with two concentrations of metformin (1mM and 5mM) concomitantly with the death inhibitors, Z-vad (10μM), Necrostatin-1 (50μM) and Deferoxamine (100μM). After 24 hours of treatment, cell viability and proliferation were analyzed, cell death analysis by flow cytometry through the staining with Annexin V and propidium iodide, and in relation to the oxidative stress parameters, total thiol, GSH, GSSG and malondialdehyde . The results showed that after the treatment with the two metformin concentrations there was a reduction in the viability and proliferation of the cells, however, regarding the concomitant treatment of metformin with the inhibitors, these indices were restored. Regarding the parameters of oxidative stress, metformin reduced levels of antioxidants (total thiol, GSH and GSSG), but in the concomitant treatment with the death inhibitors the antioxidants were preserved. Regarding the lipoperoxidation marker, malondialdehyde, the two concentrations of metformin were able to increase their concentration. These results suggest that metformin does not induce only one type of cell death, since the three death inhibitors used were able to reverse the toxic effects of the drug. As for the generation of oxidative stress, treatment with death inhibitors seems to protect the cells from metformin-induced death, consistent with the previously reported results that metformin-induced death would be associated with the generation of oxidative stress.

O câncer de pele não-melanoma (CPNM) é a neoplasia mais comum na população humana. A radiação UVB (290-320nm) penetra a epiderme e é diretamente absorvida pelo DNA, induzindo mutações, ativando vias inflamatórias e promovendo a geração de espécies reativas de oxigênio (ROS), sendo o principal agente carcinogênico para o câncer de pele. O CPNM é dividido em duas formas principais, o carcinoma de células basais e o carcinoma de células escamosas, ambos são derivados de queratinócitos epidérmicos e desenvolvem-se nas áreas da pele mais expostas à luz ultravioleta (UV). A melhor maneira de prevenção é evitar queimaduras solares, controlando o tempo de exposição ao sol e com o uso de bloqueadores solares. Recentemente novas abordagens tem proposto o uso de produtos naturais seja por aplicação tópica ou via oral. O citral é um óleo essencial, composto por uma mistura de isômeros neral (cis) e geranial (trans), naturalmente encontrado em algumas plantas como o capim-limão (Cymbopogon citratus). Apresenta forte aroma de limão, e por isso é utilizado na indústria como aromatizante alimentício e cosmético. Em modelos in vitro, tem demonstrado propriedades antibacterianas, antifúngicas, antiparasitária e efeitos anticarcinogênicos. O presente trabalho avaliou a atividade quimioprotetora do citral no CPNM, afim de elucidar os mecanismos envolvidos neste efeito. Nós utilizamos camundongos hairless (sem pêlos) HRS/J, machos, de 8-12 semanas de idade, com peso entre 25-32g, desvermifugados e mantidos sob condições específicas. O protocolo de indução da carcinogênese da pele por radiação UVB, teve duração de 24 semanas, e foi dividido em fase de iniciação, descanso e fase de promoção. A irradiação foi realizada em uma câmara de irradiação com uma lâmpada fluorescente PHILLIPS TL / 12 40W UVB. A dose de radiação acumulada foi de 13,875 J/cm². Os grupos foram tratados com citral em diferentes concentrações (0,1, 0,5 e 1%), tendo como base o gel carbopol 940, aplicado a uma dosagem de 0,1 g/animal, 5 minutos após a exposição UVB. Foram avaliados o número e tamanho das lesões cutâneas, avaliação histológica (H&E) da pele, parâmetros de estresse oxidativo cutâneo (capacidade antioxidante total, atividade da catalase e malondialdeído na pele), apoptose e citocinas (IL-1β, IL-4, IL-23, TNF-α, INFγ e IL-10). Os resultados foram expressos como média ± desvio padrão, usando o One-way ANOVA seguido pelo teste Tukey. As diferenças foram consideradas significativas para p