RESUMO
PURPOSE OF REVIEW: Cachexia is a complex, multifactorial syndrome primarily characterized by weight loss, muscle wasting, anorexia, and systemic inflammation. It is prevalent in cancer patients and is associated with a poor prognosis, including lower resistance to intervention toxicity, quality of life, and survival, compared to patients without the syndrome. The gut microbiota and its metabolites have been shown to influence host metabolism and immune response. Our article reviews the current evidence suggesting a role of gut microbiota in the development and progression of cachexia, while discussing the potential mechanisms involved. We also describe promising interventions targeting gut microbiota aiming to improve outcomes related to cachexia. RECENT FINDINGS: Dysbiosis, an imbalance in gut microbiota, has been associated with cancer cachexia through pathways involving muscle wasting, inflammation, and gut barrier dysfunction. Interventions targeting gut microbiota, such as probiotics, prebiotics, synbiotics, and fecal microbiota transplantation, have shown promising results in managing this syndrome in animal models. However, evidence in humans is currently limited. SUMMARY: Mechanisms linking gut microbiota and cancer cachexia need to be further explored, and additional human research is necessary to evaluate the appropriate dosages, safety, and long-term outcomes of prebiotic and probiotic use in microbiota management for cancer cachexia.
Assuntos
Microbioma Gastrointestinal , Neoplasias , Probióticos , Simbióticos , Animais , Humanos , Microbioma Gastrointestinal/fisiologia , Caquexia/terapia , Caquexia/complicações , Qualidade de Vida , Probióticos/uso terapêutico , Neoplasias/complicações , Prebióticos , Inflamação/complicações , Disbiose/complicaçõesRESUMO
Increased muscle protein catabolism leading to muscle wasting is a prominent feature of the syndrome of protein-energy wasting (PEW) in patients with chronic kidney disease (CKD). PEW and muscle wasting are induced by factors such as inflammation, oxidative stress and metabolic acidosis that activate the ubiquitin-proteasome system, the main regulatory mechanism of skeletal muscle degradation. Whether deficiency of nuclear factor erythroid 2-related factor 2 (NRF2), which regulates expression of antioxidant proteins protecting against oxidative damage triggered by inflammation, may exacerbate PEW has yet to be examined in aging patients with CKD. This review focuses on the hypothesis that NRF2 is involved in the maintenance of muscle mass and explores whether sustained activation of NRF2 by non-pharmacological interventions using nutraceutical activators to improve redox homeostasis could be a plausible strategy to prevent skeletal muscle disorders, including muscle wasting, sarcopenia and frailty associated with PEW in aging CKD patients.
Assuntos
Fator 2 Relacionado a NF-E2 , Insuficiência Renal Crônica , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/prevenção & controle , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/metabolismo , Caquexia/complicações , Caquexia/metabolismo , Caquexia/patologia , Envelhecimento , Músculo Esquelético/metabolismo , Inflamação/complicaçõesRESUMO
Cancer cachexia is associated with deficient response to chemotherapy. On the other hand, the tumors of cachectic patients remarkably express more chemokines and have higher immune infiltration. For immunogenicity, a strong induction of the unfolded protein response (UPR) is necessary. UPR followed by cell surface exposure of calreticulin on the dying tumor cell is essential for its engulfment by macrophages and dendritic cells. However, some tumor cells upon endoplasmic reticulum (ER) stress can release factors that induce ER stress to other cells, in the so-called transmissible ER stress (TERS). The cells that received TERS produce more interleukin 6 (IL-6) and chemokines and acquire resistance to subsequent ER stress, nutrient deprivation, and genotoxic stress. Since ER stress enhances the release of extracellular vesicles (EVs), we suggest they can mediate TERS. It was found that ER stressed cachexia-inducing tumor cells transmit factors that trigger ER stress in other cells. Therefore, considering the role of EVs in cancer cachexia, the release of exosomes can possibly play a role in the process of blunting the immunogenicity of the cachexia-associated tumors. We propose that TERS can cause an inflammatory and immunosuppressive phenotype in cachexia-inducing tumors.
Assuntos
Caquexia/complicações , Estresse do Retículo Endoplasmático , Neoplasias/complicações , Animais , Humanos , Macrófagos/metabolismo , Resposta a Proteínas não DobradasRESUMO
Cachexia syndrome can affect cancer patients and new prevention strategies are required. Maternal nutritional supplementation can modify metabolic programming in the offspring, which lasts until adulthood. This could be a good approach against diseases such as cancer. A 3% leucine-rich diet treatment improved muscle protein turnover by modifying the mTOR and proteolytic pathways, thus we analysed whether maternal supplementation could ameliorate muscle protein turnover in adult offspring tumour-bearing rats. Pregnant Wistar rats received a control diet or 3% leucine-rich diet during pregnancy/lactation, and their weaned male offspring received a control diet until adulthood when they were distributed into following groups (n = 7-8 per group): C, Control; W, tumour-bearing; L, without tumour with a maternal leucine-rich diet; and WL, tumour-bearing with a maternal leucine-rich diet. Protein synthesis and degradation were assessed in the gastrocnemius muscle, focusing on the mTOR pathway, which was extensively altered in W group. However, the WL adult offspring showed no decrease in muscle weight, higher food intake, ameliorated muscle turnover, activated mTOR and p70S6K, and maintained muscle cathepsin H and calpain activities. Maternal leucine nutritional supplementation could be a positive strategy to improve muscle protein balance in cancer cachexia-induced muscle damage in adult offspring rats.
Assuntos
Caquexia/complicações , Dieta , Leucina/análise , Mães , Proteínas Musculares/biossíntese , Proteínas Musculares/metabolismo , Músculos/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Caquexia/metabolismo , Caquexia/patologia , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculos/metabolismo , Músculos/patologia , Neoplasias/complicações , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Proteólise/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Severe rheumatoid cachexia is associated with pronounced loss of muscle and fat mass in patients with advanced rheumatoid arthritis. This condition is associated with dyslipidemia and predisposition to cardiovascular diseases. Circulating levels of triglycerides (TG) and free fatty acids (FFA) have not yet been consistently defined in severe arthritis. Similarly, the metabolism of these lipids in the arthritic liver has not yet been clarified. Aiming at filling these gaps this study presents a characterization of the circulating lipid profile and of the fatty acids uptake and metabolism in perfused livers of rats with adjuvant-induced arthritis. The levels of TG and total cholesterol were reduced in both serum (10-20%) and liver (20-35%) of arthritic rats. The levels of circulating FFA were 40% higher in arthritic rats, possibly in consequence of cytokine-induced adipose tissue lipolysis. Hepatic uptake and oxidation of palmitic and oleic acids was higher in arthritic livers. The phenomenon results possibly from a more oxidized state of the arthritic liver. Indeed, NADPH/NADP+ and NADH/NAD+ ratios were 30% lower in arthritic livers, which additionally presented higher activities of the citric acid cycle driven by both endogenous and exogenous FFA. The lower levels of circulating and hepatic TG possibly are caused by an increased oxidation associated to a reduced synthesis of fatty acids in arthritic livers. These results reveal that the lipid hepatic metabolism in arthritic rats presents a strong catabolic tendency, a condition that should contribute to the marked cachexia described for arthritic rats and possibly for the severe rheumatoid arthritis.
Assuntos
Artrite Experimental/metabolismo , Ácidos Graxos/metabolismo , Fígado/metabolismo , Animais , Artrite Experimental/complicações , Artrite Experimental/patologia , Caquexia/complicações , Caquexia/metabolismo , Caquexia/patologia , Ingestão de Alimentos/fisiologia , Jejum/metabolismo , Corpos Cetônicos/metabolismo , Metabolismo dos Lipídeos , Fígado/patologia , Masculino , Oxirredução , Ratos , Ratos Sprague-DawleyRESUMO
Metformin (MET) is widely used in the correction of insulin (INS) resistance and metabolic abnormalities in type 2 diabetes. However, its effect on INS resistance and metabolic disorders associated with cancer cachexia is not established. We investigated the MET effects, isolated or associated with INS, on INS resistance and metabolic changes induced by Walker-256 tumor in rats with advanced cachexia. MET (500 mg·kg-1, oral) and MET + INS (1.0 IU·kg-1, s.c.) were administered for 12 days, starting on the day of tumor cell inoculation. Tumor-bearing rats showed adipose and muscle mass wasting, body mass loss, anorexia, decreased Akt phosphorylation in retroperitoneal and mesenteric adipose tissue, peripheral INS resistance, hypoinsulinemia, reduced INS content and secretion from pancreatic islets, and also inhibition of glycolysis, gluconeogenesis, and glycogenolysis in liver. MET and MET + INS treatments did not prevent these changes. It can be concluded that treatments with MET and MET + INS did not prevent the adipose and muscle mass wasting and body mass loss of tumor-bearing rats possibly by not improving INS resistance. Therefore, MET, used for the treatment of INS resistance in type 2 diabetes, is not effective in improving INS resistance in the advanced stage of cancer cachexia, evidencing that the drug does not have the same beneficial effect in these 2 diseases.
Assuntos
Caquexia/complicações , Caquexia/metabolismo , Resistência à Insulina , Metformina/farmacologia , Neoplasias/complicações , Animais , Caquexia/tratamento farmacológico , Caquexia/patologia , Insulina/metabolismo , Masculino , Metformina/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacosRESUMO
Cachexia is the main cause of mortality in advanced cancer patients. We investigated the effects of insulin (INS) and glutamine dipeptide (GDP), isolated or associated, on cachexia and metabolic changes induced by Walker 256 tumor in rats. INS (NPH, 40 UI/kg, sc) or GDP (1.5g/kg, oral gavage) was once-daily administered during 11 days after tumor cell inoculation. GDP, INS or INS+GDP treatments did not influence the tumor growth. However, INS and INS+GDP prevented retroperitoneal fat wasting and body weight loss of tumor-bearing rats. In consistency, INS and INS+GDP prevented the increased expression of triacylglycerol lipase (ATGL) and hormone sensitive lipase (HSL), without changing the expression of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in the retroperitoneal adipose tissue of tumor-bearing rats. INS and INS+GDP also prevented anorexia and hyperlactatemia of tumor-bearing rats. However, INS and INS+GDP accentuated the loss of muscle mass (gastrocnemius, soleus and long digital extensor) without affecting the myostatin expression in the gastrocnemius muscle and blood corticosterone. GDP treatment did not promote beneficial effects. It can be concluded that treatment with INS (INS or INS+GDP), not with GDP, prevented fat wasting and weight loss in tumor-bearing rats without reducing tumor growth. These effects might be attributed to the reduction of lipases expression (ATGL and LHS) and increased food intake. The results show the physiological function of INS in the suppression of lipolysis induced by cachexia mediators in tumor-bearing rats.
Assuntos
Tecido Adiposo/efeitos dos fármacos , Caquexia/prevenção & controle , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Lipase/metabolismo , Neoplasias Mamárias Animais/complicações , Redução de Peso/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Caquexia/complicações , Linhagem Celular Tumoral , Interleucina-6/metabolismo , Masculino , Neoplasias Mamárias Animais/enzimologia , Neoplasias Mamárias Animais/patologia , Neoplasias Mamárias Animais/fisiopatologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Cancer cachexia is a multifactorial syndrome that dramatically decreases survival. Loss of white adipose tissue (WAT) is one of the key characteristics of cachexia. WAT wasting is paralleled by microarchitectural remodeling in cachectic cancer patients. Fibrosis results from uncontrolled ECM synthesis, a process in which, transforming growth factor-beta (TGFß) plays a pivotal role. So far, the mechanisms involved in adipose tissue (AT) re-arrangement, and the role of TGFß in inducing AT remodeling in weight-losing cancer patients are poorly understood. This study examined the modulation of ECM components mediated by TGFß pathway in fibrotic AT obtained from cachectic gastrointestinal cancer patients. METHODS: After signing the informed consent form, patients were enrolled into the following groups: cancer cachexia (CC, n = 21), weight-stable cancer (WSC, n = 17), and control (n = 21). The total amount of collagen and elastic fibers in the subcutaneous AT was assessed by histological analysis and by immunohistochemistry. TGFß isoforms expression was analyzed by Multiplex assay and by immunohistochemistry. Alpha-smooth muscle actin (αSMA), fibroblast-specific protein (FSP1), Smad3 and 4 were quantified by qPCR and/or by immunohistochemistry. Interleukin (IL) 2, IL5, IL8, IL13 and IL17 content, cytokines known to be associated with fibrosis, was measured by Multiplex assay. RESULTS: There was an accumulation of collagen and elastic fibers in the AT of CC, as compared with WSC and controls. Collagens type I, III, VI, and fibronectin expression was enhanced in the tissue of CC, compared with both WSC and control. The pronounced expression of αSMA in the surrounding of adipocytes, and the increased mRNA content for FSP1 (20-fold) indicate the presence of activated myofibroblasts; particularly in CC. TGFß1 and TGFß3 levels were up-regulated by cachexia in AT, as well in the isolated adipocytes. Smad3 and Smad4 labeling was found to be more evident in the fibrotic areas of CC adipose tissue. CONCLUSIONS: Cancer cachexia promotes the development of AT fibrosis, in association with altered TGFß signaling, compromising AT organization and function.
Assuntos
Tecido Adiposo/patologia , Caquexia/metabolismo , Neoplasias/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Actinas/genética , Actinas/metabolismo , Adulto , Idoso , Caquexia/complicações , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Feminino , Fibrose/complicações , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/patologia , Isoformas de Proteínas/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas Smad/genética , Proteínas Smad/metabolismoRESUMO
Gastrointestinal dysmotility frequently occurs in cancer cachexia and may result from damage to enteric innervation caused by oxidative stress, especially due to glutathione depletion. We assessed the effect of dietary supplementation with 20 g/kg l-glutamine (a glutathione precursor) on the intrinsic innervation of the enteric nervous system in healthy and Walker 256 tumor-bearing Wistar rats during the development of experimental cachexia (14 days), in comparison with non-supplemented rats, by using immunohistochemical methods and Western blotting. The total neural population and cholinergic subpopulation densities in the myenteric plexus, as well as the total population and VIPergic subpopulation in the submucosal plexus of the jejunum and ileum, were reduced in cachectic rats, resulting in adaptive morphometric alterations and an increase in vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) expression, suggesting a neuroplastic response. l-glutamine supplementation prevented decrease in myenteric neuronal density in the ileum, morphometric alterations in the neurons and nerve fibers (in both the plexuses of the jejunum and ileum), and the overexpression of VIP and CGRP. Cancer cachexia severely affected the intrinsic innervation of the jejunum and ileum to various degrees and this injury seems to be associated with adaptive neural plasticity. l-glutamine supplementation presented partial protective effects on the enteric innervation against cancer cachexia, possibly by attenuating oxidative stress.
Assuntos
Caquexia/complicações , Suplementos Nutricionais , Glutamina/administração & dosagem , Mucosa Intestinal/metabolismo , Neoplasias/complicações , Neurônios/patologia , Caquexia/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias/patologiaRESUMO
AIMS: Resistance exercise training (RET) has been adopted as non-pharmacological anti-catabolic strategy. However, the role of RET to counteract cancer cachexia is still speculative. This study aimed to verify whether short-term RET would counteract skeletal muscle wasting in a severe cancer cachexia rat model. MAIN METHODS: Wistar rats were randomly allocated into four experimental groups; 1) untrained control rats (control), 2) rats submitted to RET (control+RET), 3) untrained rats injected with Walker 256 tumor cells in the bone marrow (tumor) and 4) rats injected with Walker 256 tumor cells in the bone marrow and submitted to RET (tumor+RET). KEY FINDINGS: Tumor group displayed skeletal muscle atrophy fifteen days post tumor cells injection as assessed by plantaris (-20.5%) and EDL (-20.0%) muscle mass. EDL atrophy was confirmed showing 43.8% decline in the fiber cross sectional area. Even though RET increased the lactate dehydrogenase protein content and fully restored phosphorylated form of 4EBP-1 to the control levels in skeletal muscle, it failed to rescue muscle morphology in tumor-bearing rats. Indeed, RET did not mitigated loss of muscle function, anorexia, tumor growth or mortality rate. However, loss of strength capacity (assessed by 1-RM test performance) demonstrated a negative correlation with rats' survival (p=0.02; r=0.40), suggesting that loss of strength capacity might predict cancer mortality. SIGNIFICANCE: These results demonstrated that bone marrow injection of Walker 256 tumor cells in rats induces cancer cachexia, strength capacity is associated with cancer survival and short-term RET promotes only modest effects during cachexia progression.