The role of insulin resistance in the development of muscle wasting during cancer cachexia

The efficacy and safety of anamorelin among patients with diabetes

BACKGROUND

Anamorelin is a selective ghrelin receptor agonist approved for cancer cachexia in Japan. Little is known about predictors of anamorelin efficacy. This study aimed to assess the effect of diabetes on the efficacy and safety of anamorelin in patients with cancer cachexia.

METHODS

Medical records of patients with advanced non-small-cell lung, gastric, pancreatic, or colorectal cancer who received anamorelin between January 2021 and March 2023 were retrospectively reviewed. The diabetic (DM) group included patients with a confirmed diagnosis of type 2 diabetes mellitus, random plasma glucose of ≥ 200 mg/dL, or hemoglobin A1c of ≥ 6.5%. The maximum body weight gain and adverse events during anamorelin administration were compared between the DM and non-DM groups. Patients with a maximum body weight gain ≥ 0 kg were classified as the responders.

RESULTS

Of 103 eligible patients, 31 (30.1%) were assigned to the DM group. The DM group gained less weight (median of -0.53% vs. + 3.00%, p < 0.01) and had fewer responders (45.2% vs. 81.9%, p < 0.01) than the non-DM group. The odds ratio for non-response in the DM group was 6.55 (95% confidential interval 2.37-18.06, p < 0.01), adjusted by age and performance status. The DM group had a higher cumulative incidence of hyperglycaemic adverse events (72.2% vs. 6.3%, p < 0.01) and more discontinuations due to hyperglycaemic adverse events (25.8% vs. 4.2%, p < 0.01) than the non-DM group.

CONCLUSIONS

Patients with diabetes and cancer cachexia are less likely to gain weight with anamorelin despite a high risk of hyperglycaemic adverse events.

Influence of Amino Acids and Exercise on Muscle Protein Turnover, Particularly in Cancer Cachexia

Cancer cachexia is a multifaceted syndrome that impacts individuals with advanced cancer. It causes numerous pathological changes in cancer patients, such as inflammation and metabolic dysfunction, which further diminish their quality of life. Unfortunately, cancer cachexia also increases the risk of mortality in affected individuals, making it an important area of focus for cancer research and treatment. Several potential nutritional therapies are being tested in preclinical and clinical models for their efficacy in improving muscle metabolism in cancer patients. Despite promising results, no special nutritional therapies have yet been validated in clinical practice. Multiple studies provide evidence of the benefits of increasing muscle protein synthesis through an increased intake of amino acids or protein. There is also increasing evidence that exercise can reduce muscle atrophy by modulating protein synthesis. Therefore, the combination of protein intake and exercise may be more effective in improving cancer cachexia. This review provides an overview of the preclinical and clinical approaches for the use of amino acids with and without exercise therapy to improve muscle metabolism in cachexia.

Changes in physical activity and diabetes risk after cancer diagnosis: a nationwide cohort study

PURPOSE

Physical activity has the potential to reduce the risk of diabetes after cancer diagnosis. However, current evidence supporting its effects is limited. This study aims to examine the associations between changes in physical activity and subsequent risk of diabetes among cancer survivors.

METHODS

A total of 264,250 cancer survivors (mean age 56.7 (12.5) years, 44.2% males) without a prior history of diabetes were assessed for adherence to physical activity both before and after their diagnosis. The primary outcome was incident diabetes. The Fine-Gray proportional sub-distribution hazards model was used to calculate sub-distribution hazard ratios (sHRs) and 95% confidence intervals (CIs) for diabetes risk, considering death as a competing risk.

RESULTS

Over a follow-up of 1,065,802 person-years, maintaining regular physical activity from pre-diagnosis was associated with a 10% reduced risk of diabetes after cancer diagnosis (sHR 0.90, 95% CI 0.85-0.96), considering traditional diabetes risk factors, sociodemographics, and primary cancer sites. Cancer survivors who became active and inactive after their cancer diagnosis exhibited a marginally decreased risk of diabetes (sHR 0.98, 95% CI 0.93-1.03; sHR 0.97, 95% CI 0.92-1.03). The strength and direction of the association varied depending on the primary site of cancer.

CONCLUSIONS

Regular physical activity starting before a cancer diagnosis is associated with a lower risk of diabetes following the diagnosis, independent of established diabetes risk factors.

IMPLICATIONS FOR CANCER SURVIVORS

The study underscores the importance of engaging in sufficient physical activity to mitigate the risk of diabetes in cancer survivors.

Metabolic underpinnings of cancer-related fatigue

Cancer-related fatigue (CRF) is one of the most prevalent and detrimental complications of cancer. Emerging evidence suggests that obesity and insulin resistance are associated with CRF occurrence and severity in cancer patients and survivors. In this narrative review, we analyzed recent studies including both preclinical and clinical research on the relationship between obesity and/or insulin resistance and CRF. We also describe potential mechanisms for these relationships, though with the caveat that because the mechanisms underlying CRF are incompletely understood, the mechanisms mediating the association between obesity/insulin resistance and CRF are similarly incompletely delineated. The data suggest that, in addition to their effects to worsen CRF by directly promoting tumor growth and metastasis, obesity and insulin resistance may also contribute to CRF by inducing chronic inflammation, neuroendocrinological disturbance, and metabolic alterations. Furthermore, studies suggest that patients with obesity and insulin resistance experience more cancer-induced pain and are at more risk of emotional and behavioral disruptions correlated with CRF. However, other studies implied a potentially paradoxical impact of obesity and insulin resistance to reduce CRF symptoms. Despite the need for further investigation utilizing interventions to directly elucidate the mechanisms of cancer-related fatigue, current evidence demonstrates a correlation between obesity and/or insulin resistance and CRF, and suggests potential therapeutics for CRF by targeting obesity and/or obesity-related mediators.

Nutrition and Lifestyle-Related Factors as Predictors of Muscle Atrophy in Hematological Cancer Patients

BACKGROUND

Cancer and side effects from cytostatic treatment commonly affect nutritional status manifested as a decrease in muscle mass. We aimed to investigate the impact of nutrition and lifestyle-related factors on muscle mass in patients with hematological cancer.

METHODS

Dietary intake, food preferences, quality of life (QoL), and physical activity level (PAL) were monitored during 1-2 cytostatic treatment series. Body composition was estimated using bioelectrical impedance analysis (BIA).

RESULTS

61 patients were included. Weight loss and loss of muscle mass were detected in 64% and 59% of the patients, respectively. Muscle mass was significantly positively correlated to increasing PAL (p = 0.003), while negatively correlated to increasing age (p = 0.03), physical QoL (p = 0.007), functional QoL (p = 0.05), self-perceived health (p = 0.004), and self-perceived QoL (p = 0.007). Weight was significantly positively correlated to increased intake of soft drinks (p = 0.02) as well as the favoring of bitter grain and cereal products (p = 0.03), while negatively correlated to increasing age (p = 0.03) and increasing meat intake (p = 0.009) Conclusions: Several nutritional and lifestyle-related factors affected change in body composition. The clinical significance of these changes should be investigated in controlled, interventional studies.

Peripheral insulin resistance is early, progressive, and correlated with cachexia in Walker-256 tumor-bearing rats

Insulin (INS) resistance is often found in cancer-bearing, but its correlation with cachexia development is not completely established. This study investigated the temporal sequence of the development of INS resistance and cachexia to establish the relationship between these factors in Walker-256 tumor-bearing rats (TB rats). INS hepatic sensitivity and INS resistance-inducing factors, such as free fatty acids (FFA) and tumor necrosis factor-α (TNF-α), were also evaluated. Studies were carried out on Days 2, 5, 8, and/or 12 after inoculation of tumor cells in rats. The peripheral INS sensitivity was assessed by the INS tolerance test and the INS hepatic sensitivity in in situ liver perfusion. TB rats with 5, 8, and 12 days of tumor, but not 2 days, showed decreased peripheral INS sensitivity (INS resistance), retroperitoneal fat, and body weight, compared to healthy rats, which were more pronounced on Day 12. Gastrocnemius muscle wasting was observed only on Day 12 of tumor. The peripheral INS resistance was significantly correlated (r = -.81) with weight loss. Liver INS sensitivity of TB rats with 2 and 5 days of tumor was unchanged, compared to healthy rats. TB rats with 12 days of tumor showed increased plasma FFA and increased TNF-α in retroperitoneal fat and liver, but not in the gastrocnemius, compared to healthy rats. In conclusion, peripheral INS resistance is early, starts along with fat and weight loss and before muscle wasting, progressive, and correlated with cachexia, suggesting that it may play an important role in the pathogenesis of the cachectic process in TB rats. Therefore, early correction of INS resistance may be a therapeutic approach to prevent and treat cancer cachexia.

Mechanisms of Ovarian Cancer-Associated Cachexia

Cancer-associated cachexia occurs in 50% to 80% of cancer patients and is responsible for 20% to 30% of cancer-related deaths. Cachexia limits survival and treatment outcomes, and is a major contributor to morbidity and mortality during cancer. Ovarian cancer is one of the leading causes of cancer-related deaths in women, and recent studies have begun to highlight the prevalence and clinical impact of cachexia in this population. Here, we review the existing understanding of cachexia pathophysiology and summarize relevant studies assessing ovarian cancer-associated cachexia in clinical and preclinical studies. In clinical studies, there is increased evidence that reduced skeletal muscle mass and quality associate with worse outcomes in subjects with ovarian cancer. Mouse models of ovarian cancer display cachexia, often characterized by muscle and fat wasting alongside inflammation, although they remain underexplored relative to other cachexia-associated cancer types. Certain soluble factors have been identified and successfully targeted in these models, providing novel therapeutic targets for mitigating cachexia during ovarian cancer. However, given the relatively low number of studies, the translational relevance of these findings is yet to be determined and requires more research. Overall, our current understanding of ovarian cancer-associated cachexia is insufficient and this review highlights the need for future research specifically aimed at exploring mechanisms of ovarian cancer-associated cachexia by using unbiased approaches and animal models representative of the clinical landscape of ovarian cancer.

Unravelling the Role of Cancer Cell-Derived Extracellular Vesicles in Muscle Atrophy, Lipolysis, and Cancer-Associated Cachexia

Cancer-associated cachexia is a metabolic syndrome that causes significant reduction in whole-body weight due to excessive loss of muscle mass accompanied by loss of fat mass. Reduced food intake and several metabolic abnormalities, such as increased energy expenditure, excessive catabolism, and inflammation, are known to drive cachexia. It is well documented that cancer cells secrete EVs in abundance which can be easily taken up by the recipient cell. The cargo biomolecules carried by the EVs have the potential to alter the signalling pathways and function of the recipient cells. EV cargo includes proteins, nucleic acids, lipids, and metabolites. Tumour-secreted EVs have been found to alter the metabolic and biological functions of adipose and muscle tissue, which aids in the development of the cachexia phenotype. To date, no medical intervention or FDA-approved drug exists that can completely reverse cachexia. Therefore, understanding how cancer-derived EVs contribute to the onset and progression of cancer-associated cachexia may help with the identification of new biomarkers as well as provide access to novel treatment alternatives. The goal of this review article is to discuss the most recent research on cancer-derived EVs and their function in cellular crosstalk that promotes catabolism in muscle and adipose tissue during cancer-induced cachexia.

Pancreatic Cancer-Derived Exosomal miR-Let-7b-5p Stimulates Insulin Resistance in Skeletal Muscle Cells Through RNF20/STAT3/FOXO1 Axis Regulation

Background

Cancers trigger systemic metabolic disorders usually associated with glucose intolerance, which is an initially apparent phenomenon. One of the features of pancreatic cancer (PC) metabolic reprogramming is the crosstalk between PC and peripheral tissues (skeletal muscle and adipose tissues), emphasized by insulin resistance (IR). Our previous study reported that mice pancreatic cancer-derived exosomes could induce skeletal muscle cells (C2C12) IR, and exosomal microRNAs (miRNAs) may exert an important effect. However, the underlying mechanism remains to be further elucidated.

Methods

qPCR was used to determine the expression of let-7b-5p in normal pancreatic islet cells and PC cells. Exosomes were purified from PC cell culture medium by ultracentrifugation. The role let-7b-5p on IR-mediated by PC cells-derived exosomes was asses by Oil Red O staining using miRNA inhibitor. Western blot assay was performed to examine the expression of IR-related genes and the activation of signaling pathways. A Luciferase experiment was applied to confirm how let-7b-5p regulated the expression of RNF20. IP/WB analysis further determined whether RNF20 promoted STAT3 ubiquitination. Rescue experiment using RNF20 overexpression plasmid was performed to confirm the role of RNF20 on IR-mediated using PC cell-derived exosomes in C2C12 myotube cells.

Results

miRNA-let-7b-5p was identified as the key exosomal miRNA, which could promote the IR in C2C12 myotube cells supported the lipid accumulation, the activation of STAT3/FOXO1 axis, and the decreased expression of IRS-1 and GLUT4. RNF20, an E3 ubiquitin ligase, was confirmed as the target gene of let-7b-5p and was found to improve IR by downregulating STAT3 protein expression via ubiquitination-mediated protein degradation. The ectopic expression of RNF20 could effectively attenuate the IR mediated by the pancreatic cancer-derived exosomes in C2C12 myotube cells.

Conclusion

Our data suggest that exosomal miRNA-let-7b-5p may promote IR in C2C12 myotube cells by targeting RNF20 to activate the STAT3/FOXO1 axis.

REPTOR and CREBRF encode key regulators of muscle energy metabolism

Metabolic flexibility of muscle tissue describes the adaptive capacity to use different energy substrates according to their availability. The disruption of this ability associates with metabolic disease. Here, using a Drosophila model of systemic metabolic dysfunction triggered by yorkie-induced gut tumors, we show that the transcription factor REPTOR is an important regulator of energy metabolism in muscles. We present evidence that REPTOR is activated in muscles of adult flies with gut yorkie-tumors, where it modulates glucose metabolism. Further, in vivo studies indicate that sustained activity of REPTOR is sufficient in wildtype muscles to repress glycolysis and increase tricarboxylic acid (TCA) cycle metabolites. Consistent with the fly studies, higher levels of CREBRF, the mammalian ortholog of REPTOR, reduce glycolysis in mouse myotubes while promoting oxidative metabolism. Altogether, our results define a conserved function for REPTOR and CREBRF as key regulators of muscle energy metabolism.

Adverse Metabolic Effects on Glucose in Patients Receiving Anamorelin Using a Japanese Claims Database

BACKGROUND

Anamorelin is the first drug approved for the treatment of cancer cachexia, a debilitating condition characterized by weight loss, anorexia, and muscle mass depletion. Cachexia negatively affects a patient's quality of life, survival, and response to chemotherapy. Studies describing anamorelin use are currently limited to a small number of pancreatic cancer cases.

OBJECTIVES

We aimed to examine the incidence and risk factors of adverse metabolic effects on glucose levels in cachexia patients with various carcinomas treated with anamorelin.

METHOD

We used real-world data of patients who received anamorelin between August 2021 and July 2022 and were registered in the JMDC claims database. We investigated the impact of metabolic adverse effects on glucose in patients receiving anamorelin with respect to the following factors: sex (male), age (>75 years), types of carcinoma, history of diabetes mellitus (DM), and concomitant use of steroids.

RESULTS

The incidence of adverse metabolic effects on glucose was 12.3%, and pancreatic cancer and history of DM were associated with adverse metabolic effects on glucose. The median onset of adverse metabolic effects on glucose was 17 days after anamorelin treatment.

CONCLUSIONS

This study highlights the need to monitor and manage hyperglycemia in cachexia patients receiving anamorelin, especially in those with pancreatic cancer and a history of DM.

Astaxanthin Supplementation Assists Sorafenib in Slowing Skeletal Muscle Atrophy in H22 Tumor-Bearing Mice via Reversing Abnormal Glucose Metabolism

SCOPE

Cachexia, which is often marked by skeletal muscular atrophy, is one of the leading causes of death in cancer patients. Astaxanthin, a carotenoid obtained from marine organisms that can aid in the prevention and treatment of a variety of disorders. In this study, to assess whether astaxanthin ameliorates weight loss and skeletal muscle atrophy in sorafenib-treated hepatocellular carcinoma mice is aimed.

METHODS AND RESULTS

H22 mice are treated with 30 mg kg-1  day-1 of sorafenib and 60 mg kg-1  day-1 of astaxanthin by gavage lasted for 18 days. Sorafenib does not delay skeletal muscle atrophy and weight loss, although it does not reduce tumor burden. Astaxanthin dramatically delays weight loss and skeletal muscle atrophy in sorafenib-treating mice, without affecting the food intake. Astaxanthin inhibits the tumor glycolysis, slows down gluconeogenesis, and improves insulin resistance in tumor-bearing mice. Astaxanthin increases glucose competition in skeletal muscle by targeting the PI3K/Akt/GLUT4 signaling pathway, and enhances glucose utilization efficiency in skeletal muscle, thereby slowing skeletal muscle atrophy.

CONCLUSION

The findings show the significant potential of astaxanthin as nutritional supplements for cancer patients, as well as the notion that nutritional interventions should be implemented at the initiation of cancer treatment, as instead of waiting until cachexia sets in.

High burden of diabetes and prediabetes among cancer patients at University of Gondar comprehensive specialized hospital, Northwest Ethiopia

Cancer and diabetes mellitus (DM) are diagnosed within the same individual more frequently and share common risk factors. Although diabetes among cancer patients may result in more aggressive clinical courses of cancer, there is limited evidence about its burden and associated factors. Hence, this study aimed to assess the burden of diabetes and prediabetes among cancer patients and its associated factors. Institution-based cross-sectional study was conducted at the University of Gondar comprehensive specialized hospital from 10 January to 10 March 2021. A systematic random sampling technique was used to select 423 cancer patients. The data was collected using a structured interviewer-administered questionnaire. Prediabetes and diabetes diagnosis was made based on World Health Organization (WHO) criteria. Bi-variable and multivariable binary logistic regression models were fitted to identify factors associated with the outcome. Adjusted Odds Ratio (AOR) with a 95% confidence interval was estimated to show the direction and strength of associations. Variables with a p-value less than 0.05 in the multivariable model were considered significantly associated with the outcome. The final analysis was based on 384 patients with cancer. The proportion of prediabetes and diabetes was 56.8% (95% CI 51.7, 61.7) and 16.7% (95% CI 13.3, 20.8), respectively. Alcohol consumption was found to increase the odds of elevated blood sugar among cancer patients (AOR: 1.96; 95%CI: 1.11, 3.46). The burden of prediabetes and diabetes is alarmingly high among cancer patients. Besides, alcohol consumption was found to increase the odds of having elevated blood sugar among cancer patients. Hence, it is essential to recognize cancer patients are at high risk of having elevated blood sugar and design strategies to integrate diabetes and cancer care.

Cancer cachexia: molecular mechanisms and treatment strategies

Muscle wasting is a consequence of physiological changes or a pathology characterized by increased catabolic activity that leads to progressive loss of skeletal muscle mass and strength. Numerous diseases, including cancer, organ failure, infection, and aging-associated diseases, are associated with muscle wasting. Cancer cachexia is a multifactorial syndrome characterized by loss of skeletal muscle mass, with or without the loss of fat mass, resulting in functional impairment and reduced quality of life. It is caused by the upregulation of systemic inflammation and catabolic stimuli, leading to inhibition of protein synthesis and enhancement of muscle catabolism. Here, we summarize the complex molecular networks that regulate muscle mass and function. Moreover, we describe complex multi-organ roles in cancer cachexia. Although cachexia is one of the main causes of cancer-related deaths, there are still no approved drugs for cancer cachexia. Thus, we compiled recent ongoing pre-clinical and clinical trials and further discussed potential therapeutic approaches for cancer cachexia.

Tumor Cytokine-Induced Hepatic Gluconeogenesis Contributes to Cancer Cachexia: Insights from Full Body Single Nuclei Sequencing

A primary cause of death in cancer patients is cachexia, a wasting syndrome attributed to tumor-induced metabolic dysregulation. Despite the major impact of cachexia on the treatment, quality of life, and survival of cancer patients, relatively little is known about the underlying pathogenic mechanisms. Hyperglycemia detected in glucose tolerance test is one of the earliest metabolic abnormalities observed in cancer patients; however, the pathogenesis by which tumors influence blood sugar levels remains poorly understood. Here, utilizing a Drosophila model, we demonstrate that the tumor secreted interleukin-like cytokine Upd3 induces fat body expression of Pepck1 and Pdk, two key regulatory enzymes of gluconeogenesis, contributing to hyperglycemia. Our data further indicate a conserved regulation of these genes by IL-6/JAK-STAT signaling in mouse models. Importantly, in both fly and mouse cancer cachexia models, elevated gluconeogenesis gene levels are associated with poor prognosis. Altogether, our study uncovers a conserved role of Upd3/IL-6/JAK-STAT signaling in inducing tumor-associated hyperglycemia, which provides insights into the pathogenesis of IL-6 signaling in cancer cachexia.

Cancer cachexia as a blueprint for treating obesity

Effective pharmacological treatments to achieve significant and sustained weight loss in obese individuals remain limited. Here, we apply a 'reverse engineering' approach to cancer cachexia, an extreme form of dysregulated energy balance resulting in net catabolism. We discuss three phenotypic features of the disease, summarize the underlying molecular checkpoints, and explore their translation to obesity research. We then provide examples for established pharmaceuticals, which follow a reverse engineering logic, and propose additional targets that may be of relevance for future studies. Finally, we argue that approaching diseases from this perspective may prove useful as a generic strategy to fuel the development of innovative therapies.

EDA2R-NIK signalling promotes muscle atrophy linked to cancer cachexia

Skeletal muscle atrophy is a hallmark of the cachexia syndrome that is associated with poor survival and reduced quality of life in patients with cancer¹. Muscle atrophy involves excessive protein catabolism and loss of muscle mass and strength². An effective therapy against muscle wasting is currently lacking because mechanisms driving the atrophy process remain incompletely understood. Our gene expression analysis in muscle tissues indicated upregulation of ectodysplasin A2 receptor (EDA2R) in tumour-bearing mice and patients with cachectic cancer. Here we show that activation of EDA2R signalling promotes skeletal muscle atrophy. Stimulation of primary myotubes with the EDA2R ligand EDA-A2 triggered pronounced cellular atrophy by induction of the expression of muscle atrophy-related genes Atrogin1 and MuRF1. EDA-A2-driven myotube atrophy involved activation of the non-canonical NFĸB pathway and was dependent on NFκB-inducing kinase (NIK) activity. Whereas EDA-A2 overexpression promoted muscle wasting in mice, deletion of either EDA2R or muscle NIK protected tumour-bearing mice from loss of muscle mass and function. Tumour-induced oncostatin M (OSM) upregulated muscle EDA2R expression, and muscle-specific oncostatin M receptor (OSMR)-knockout mice were resistant to tumour-induced muscle wasting. Our results demonstrate that EDA2R-NIK signalling mediates cancer-associated muscle atrophy in an OSM-OSMR-dependent manner. Thus, therapeutic targeting of these pathways may be beneficial in prevention of muscle loss.

Emerging Mechanisms of Skeletal Muscle Homeostasis and Cachexia: The SUMO Perspective

Mobility is an intrinsic feature of the animal kingdom that stimulates evolutionary processes and determines the biological success of animals. Skeletal muscle is the primary driver of voluntary movements. Besides, skeletal muscles have an immense impact on regulating glucose, amino acid, and lipid homeostasis. Muscle atrophy/wasting conditions are accompanied by a drastic effect on muscle function and disrupt steady-state muscle physiology. Cachexia is a complex multifactorial muscle wasting syndrome characterized by extreme loss of skeletal muscle mass, resulting in a dramatic decrease in life quality and reported mortality in more than 30% of patients with advanced cancers. The lack of directed treatments to prevent or relieve muscle loss indicates our inadequate knowledge of molecular mechanisms involved in muscle cell organization and the molecular etiology of cancer-induced cachexia (CIC). This review highlights the latest knowledge of regulatory mechanisms involved in maintaining muscle function and their deregulation in wasting syndromes, particularly in cachexia. Recently, protein posttranslational modification by the small ubiquitin-like modifier (SUMO) has emerged as a key regulatory mechanism of protein function with implications for different aspects of cell physiology and diseases. We also review an atypical association of SUMO-mediated pathways in this context and deliberate on potential treatment strategies to alleviate muscle atrophy.

The association between low skeletal muscle mass and low skeletal muscle radiodensity with functional impairment, systemic inflammation, and reduced survival in patients with incurable cancer

BACKGROUND AND AIMS

Factors associated with the concomitant occurrence of low muscle mass and low muscle radiodensity are unclear. This study investigated whether different skeletal muscle phenotypes are associated with functional impairment, serum inflammatory markers, and survival in patients with incurable cancer.

METHODS

Three hundred and twenty-six patients (median age, 60 years; 67.5% female) who had abdominal or pelvic computed tomography (CT) scans up to 30 days before the initial assessment were enrolled in the study. CT images were used for the assessment of skeletal muscle index (SMI) and skeletal muscle radiodensity (SMD). Optimal stratification analysis was used to derive cohort-specific cutoff points to define SMI and SMD groups with a higher risk for mortality (SMI, males <45.0 cm² /m² and females <44.0 cm² /m² ; SMD, males <34 Hounsfield units [HU] and females <30 HU). Based on these cutoffs, participants were classified into four phenotypes: low-risk SMI + low-risk SMD, high-risk SMI + low-risk SMD, low-risk SMI + high-risk SMD, and high-risk SMI + high-risk SMD.

RESULTS

Phenotypes with high-risk SMI or high-risk SMD, especially when combined, were associated with low handgrip strength, poor performance status, higher C-reactive protein, and lower serum albumin levels. The phenotypes with high-risk SMD, regardless of low-risk SMI (hazard ratio [HR], 1.74; 95% CI, 1.05-2.88) or high-risk SMI (HR, 1.99; 95% CI, 1.29-3.05) were associated with higher 90 days' mortality risk.

CONCLUSION

In patients with incurable cancer, phenotype groups with high-risk SMI and high-risk SMD, particularly when combined, were associated with worse functional impairment and inflammation. Moreover, high-risk SMD was associated with increased mortality risk.

Predictors of response to anamorelin in gastrointestinal cancer patients with cachexia: a retrospective study

PURPOSE

Anamorelin, a ghrelin receptor agonist, has recently been approved for gastric, pancreatic, and colorectal cancer patients with cachexia in Japan. However, only few studies have investigated the predictors of response to anamorelin in clinical settings. Thus, our study aimed to investigate the predictors of the response, in addition to its efficacy and safety.

METHODS

The clinical outcomes of 20 patients were evaluated during administration. They were divided into two groups based on lean body mass, responders and non-responders, and their clinical characteristics were compared.

RESULTS

The mean ± standard error (SE) variations at 12 weeks in lean body mass and handgrip strength were 2.63 ± 0.79 kg and - 1.53 ± 1.20 kg, respectively. The mean ± SE variations at 8 weeks in fasting blood glucose and hemoglobin A1c were 32.88 ± 13.77 mg/dL and 0.90 ± 0.18%, respectively. Total protein, albumin, transferrin, and prognostic nutritional index at baseline were significantly higher in responders (n = 8) than in non-responders (n = 12), whereas the neutrophil/lymphocyte and C-reactive protein/albumin ratios at baseline were significantly higher in non-responders than in responders.

CONCLUSION

The study confirmed the efficacy and safety of anamorelin and identified nutritional or systemic inflammatory markers as predictors of anamorelin response in advanced gastrointestinal cancer patients.

Increased risk of incident diabetes after therapy with immune checkpoint inhibitor compared with conventional chemotherapy: A longitudinal trajectory analysis using a tertiary care hospital database

AIMS/HYPOTHESIS

Immune checkpoint inhibitor (ICI) has been emerged as a promising cancer treatment. However, ICI use induces immune-related adverse events, including diabetes mellitus. We compared the risk of new-onset diabetes between patients receiving an ICI and those receiving conventional chemotherapy (CC).

METHODS

Using a tertiary care hospital database, we included cancer patients without a previous history of diabetes who were treated with either CC or an ICI. One-to-five nearest neighbor propensity matching was applied, and the risk of diabetes was estimated using a Cox proportional hazards model. Latent class growth modeling was performed with a trajectory approach to determine distinct clusters that followed similar glucose trajectory patterns over time.

RESULTS

Among 1326 subjects, 1105 received CC, and 221 received an ICI. The risk of new-onset diabetes was significantly higher in the ICI group than the CC group (adjusted hazard ratio 2.454, 95 % confidence interval 1.528-3.940; p < 0.001). The ICI group had a higher proportion of subjects in the trajectory cluster with an increasing glucose pattern than the CC group (10.4 % and 7.4 %, respectively). Within the ICI group, the subjects with an increasing glucose pattern were predominantly male and associated with enhanced lymphocytosis after ICI administration.

CONCLUSIONS

ICI therapy is associated with an increased risk of incident diabetes compared with CC. The glucose levels of patients treated with an ICI, especially males and those with prominent lymphocytosis after ICI treatment, need to be monitored regularly to detect ICI-associated diabetes as early as possible.

Pathological features of tissues and cell populations during cancer cachexia

Cancers remain among the most devastating diseases in the human population in spite of considerable advances in limiting their impact on lifespan and healthspan. The multifactorial nature of cancers, as well as the number of tissues and organs that are affected, have exposed a considerable diversity in mechanistic features that are reflected in the wide array of therapeutic strategies that have been adopted. Cachexia is manifested in a number of diseases ranging from cancers to diabetes and ageing. In the context of cancers, a majority of patients experience cachexia and succumb to death due to the indirect effects of tumorigenesis that drain the energy reserves of different organs. Considerable information is available on the pathophysiological features of cancer cachexia, however limited knowledge has been acquired on the resident stem cell populations, and their function in the context of these diseases. Here we review current knowledge on cancer cachexia and focus on how tissues and their resident stem and progenitor cell populations are individually affected.

Targeting cancer cachexia: Molecular mechanisms and clinical study

Cancer cachexia is a complex systemic catabolism syndrome characterized by muscle wasting. It affects multiple distant organs and their crosstalk with cancer constitute cancer cachexia environment. During the occurrence and progression of cancer cachexia, interactions of aberrant organs with cancer cells or other organs in a cancer cachexia environment initiate a cascade of stress reactions and destroy multiple organs including the liver, heart, pancreas, intestine, brain, bone, and spleen in metabolism, neural, and immune homeostasis. The role of involved organs turned from inhibiting tumor growth into promoting cancer cachexia in cancer progression. In this review, we depicted the complicated relationship of cancer cachexia with the metabolism, neural, and immune homeostasis imbalance in multiple organs in a cancer cachexia environment and summarized the treatment progress in recent years. And we discussed the molecular mechanism and clinical study of cancer cachexia from the perspective of multiple organs metabolic, neurological, and immunological abnormalities. Updated understanding of cancer cachexia might facilitate the exploration of biomarkers and novel therapeutic targets of cancer cachexia.

Impact of dietary walnuts, a nutraceutical option, on circulating markers of metabolic dysregulation in a rodent cachectic tumor model

Background:

Nutraceutical foods, like walnuts which are rich in immunonutrients, can have medicinal benefits. Dietary walnuts have been shown to slow or prevent tumor growth in mice genetically programmed to grow breast or prostate tumors. This study investigated whether walnuts could exert the same preventable effect in a transplantable carcinoma rat model.

Methods:

Eighteen rats were randomly fed a diet containing walnuts (10% of food by weight), and 36 were fed a diet without walnuts (control) for 21 days. On day 22, 18 control diet rats were switched to the walnut diet. All other animals remained on their same diet. Within each diet group, 6 rats were implanted with the Ward colon carcinoma (TB), and 12 were sham-operated. Five days later, 6 sham-operated animals were weight-matched to a TB and then pair-fed for the remainder of the study. The remaining 6 sham-operated, or non-tumor-bearing rats, were ad-lib fed.

Results:

The tissue of the walnut-eating rats showed higher omega-3 fatty acid (immunonutrient) content which did not slow or prevent tumor growth or the loss of lean and fat mass typical of this TB model. In addition, blood glucose, insulin, IGF-1, and adiponectin levels were significantly lower in the TB, demonstrating metabolic dysregulation. Again, these changes were unaltered by consuming walnuts. Plasma proteomics identified six proteins elevated in the TB, but none could be connected with the observed metabolic dysregulation.

Conclusion:

Although walnuts’ rich immunonutrient content prevented tumor growth in genetically programmed mice models, there was no effect in this model.

Cancer cachexia as a multiorgan failure: Reconstruction of the crime scene

Cachexia is a devastating syndrome associated with the end-stage of several diseases, including cancer, and characterized by body weight loss and severe muscle and adipose tissue wasting. Although different cancer types are affected to diverse extents by cachexia, about 80% of all cancer patients experience this comorbidity, which highly reduces quality of life and response to therapy, and worsens prognosis, accounting for more than 25% of all cancer deaths. Cachexia represents an urgent medical need because, despite several molecular mechanisms have been identified, no effective therapy is currently available for this devastating syndrome. Most studies focus on skeletal muscle, which is indeed the main affected and clinically relevant organ, but cancer cachexia is characterized by a multiorgan failure. In this review, we focus on the current knowledge on the multiple tissues affected by cachexia and on the biomarkers with the attempt to define a chronological pathway, which might be useful for the early identification of patients who will undergo cachexia. Indeed, it is likely that the inefficiency of current therapies might be attributed, at least in part, to their administration in patients at the late stages of cachexia.

What we have learnt from Drosophila model organism: the coordination between insulin signaling pathway and tumor cells

Cancer development is related to a variety of signaling pathways which mediate various cellular processes including growth, survival, division and competition of cells, as well as cell-cell interaction. The insulin signaling pathway interacts with different pathways and plays a core role in the regulations of all these processes. In this study, we reviewed recent studies on the relationship between the insulin signaling pathway and tumors using the Drosophila melanogaster model. We found that on one hand, the insulin pathway is normally hyperactive in tumor cells, which promotes tumor growth, and on the other hand, tumor cells can suppress the growth of healthy tissues via inhibition of their insulin pathway. Moreover, systematic disruption in glucose homeostasis also facilitates cancer development by different mechanisms. The studies on how the insulin network regulates the behaviors of cancer cells may help to discover new therapeutic treatments for cancer.

Tumor cell anabolism and host tissue catabolism-energetic inefficiency during cancer cachexia

Cancer-associated cachexia (CC) is a pathological condition characterized by sarcopenia, adipose tissue depletion, and progressive weight loss. CC is driven by multiple factors such as anorexia, excessive catabolism, elevated energy expenditure by growing tumor mass, and inflammatory mediators released by cancer cells and surrounding tissues. In addition, endocrine system, systemic metabolism, and central nervous system (CNS) perturbations in combination with cachexia mediators elicit exponential elevation in catabolism and reduced anabolism in skeletal muscle, adipose tissue, and cardiac muscle. At the molecular level, mechanisms of CC include inflammation, reduced protein synthesis, and lipogenesis, elevated proteolysis and lipolysis along with aggravated toxicity and complications of chemotherapy. Furthermore, CC is remarkably associated with intolerance to anti-neoplastic therapy, poor prognosis, and increased mortality with no established standard therapy. In this context, we discuss the spatio-temporal changes occurring in the various stages of CC and highlight the imbalance of host metabolism. We provide how multiple factors such as proteasomal pathways, inflammatory mediators, lipid and protein catabolism, glucocorticoids, and in-depth mechanisms of interplay between inflammatory molecules and CNS can trigger and amplify the cachectic processes. Finally, we highlight current diagnostic approaches and promising therapeutic interventions for CC.

Low Carbohydrate Diets for Diabetic Cardiomyopathy: A Hypothesis

Elevated blood glucose levels, insulin resistance (IR), hyperinsulinemia and dyslipidemia the key aspects of type 2 diabetes mellitus (T2DM), contribute to the development of a certain form of cardiomyopathy. This cardiomyopathy, also known as diabetic cardiomyopathy (DMCM), typically occurs in the absence of overt coronary artery disease (CAD), hypertension or valvular disease. DMCM encompasses a variety of pathophysiological processes impacting the myocardium, hence increasing the risk for heart failure (HF) and significantly worsening outcomes in this population. Low fat (LF), calorie-restricted diets have been suggested as the preferred eating pattern for patients with HF. However, LF diets are naturally higher in carbohydrates (CHO). We argue that in an insulin resistant state, such as in DMCM, LF diets may worsen glycaemic control and promote further insulin resistance (IR), contributing to a physiological and functional decline in DMCM. We postulate that CHO restriction targeting hyperinsulinemia may be able to improve tissue and systemic IR. In recent years low carbohydrate diets (LC) including ketogenic diets (KD), have emerged as a safe and effective tool for the management of various clinical conditions such as T2DM and other metabolic disorders. CHO restriction achieves sustained glycaemic control, lower insulin levels and successfully reverses IR. In addition to this, its pleiotropic effects may present a metabolic stress defense and facilitate improvement to cardiac function in patients with HF. We therefore hypothesize that patients who adopt a LC diet may require less medications and experience improvements in HF-related symptom burden.

Apelin Resistance Contributes to Muscle Loss during Cancer Cachexia in Mice

Simple Summary

Cancer cachexia is a highly debilitating syndrome involving severe body weight loss. Worldwide around 9–14.5 million cancer patients suffer from cachexia every year and many of them die because of cachexia. Our study aimed to assess the possible role of apelin against muscle loss during cancer growth given its beneficial effects against muscle atrophy during aging. We found apelin exhibiting advantageous effects against atrophy in in vitro models, but not in in vivo models, where we unraveled undesirable apelin resistance that may nullify apelin-based therapy for cancer cachexia.

Abstract

Cancer cachexia consists of dramatic body weight loss with rapid muscle depletion due to imbalanced protein homeostasis. We found that the mRNA levels of apelin decrease in muscles from cachectic hepatoma-bearing rats and three mouse models of cachexia. Furthermore, apelin expression inversely correlates with MuRF1 in muscle biopsies from cancer patients. To shed light on the possible role of apelin in cachexia in vivo, we generated apelin 13 carrying all the last 13 amino acids of apelin in D isomers, ultimately extending plasma stability. Notably, apelin D-peptides alter cAMP-based signaling in vitro as the L-peptides, supporting receptor binding. In vitro apelin 13 protects myotube diameter from dexamethasone-induced atrophy, restrains rates of degradation of long-lived proteins and MuRF1 expression, but fails to protect mice from atrophy. D-apelin 13 given intraperitoneally for 13 days in colon adenocarcinoma C26-bearing mice does not reduce catabolic pathways in muscles, as it does in vitro. Puzzlingly, the levels of circulating apelin seemingly deriving from cachexia-inducing tumors, increase in murine plasma during cachexia. Muscle electroporation of a plasmid expressing its receptor APJ, unlike apelin, preserves myofiber area from C26-induced atrophy, supporting apelin resistance in vivo. Altogether, we believe that during cachexia apelin resistance occurs, contributing to muscle wasting and nullifying any possible peptide-based treatment.

Interconnection between Cardiac Cachexia and Heart Failure—Protective Role of Cardiac Obesity

Cachexia may be caused by congestive heart failure, and it is then called cardiac cachexia, which leads to increased morbidity and mortality. Cardiac cachexia also worsens skeletal muscle degradation. Cardiac cachexia is the loss of edema-free muscle mass with or without affecting fat tissue. It is mainly caused by a loss of balance between protein synthesis and degradation, or it may result from intestinal malabsorption. The loss of balance in protein synthesis and degradation may be the consequence of altered endocrine mediators such as insulin, insulin-like growth factor 1, leptin, ghrelin, melanocortin, growth hormone and neuropeptide Y. In contrast to many other health problems, fat accumulation in the heart is protective in this condition. Fat in the heart can be divided into epicardial, myocardial and cardiac steatosis. In this review, we describe and discuss these topics, pointing out the interconnection between heart failure and cardiac cachexia and the protective role of cardiac obesity. We also set the basis for possible screening methods that may allow for a timely diagnosis of cardiac cachexia, since there is still no cure for this condition. Several therapeutic procedures are discussed including exercise, nutritional proposals, myostatin antibodies, ghrelin, anabolic steroids, anti-inflammatory substances, beta-adrenergic agonists, medroxyprogesterone acetate, megestrol acetate, cannabinoids, statins, thalidomide, proteasome inhibitors and pentoxifylline. However, to this date, there is no cure for cachexia.

Skeletal muscle mitochondrial dysfunction and muscle and whole body functional deficits in cancer patients with weight loss

Reductions in skeletal muscle mass and function are often reported in patients with cancer-associated weight loss and are associated with reduced quality of life, impaired treatment tolerance, and increased mortality. Although cellular changes, including altered mitochondrial function, have been reported in animals, such changes have been incompletely characterized in humans with cancer. Whole body and skeletal muscle physical function, skeletal muscle mitochondrial function, and whole body protein turnover were assessed in eight patients with cancer-associated weight loss (10.1 ± 4.2% body weight over 6-12 mo) and 19 age-, sex-, and body mass index (BMI)-matched healthy controls to characterize skeletal muscle changes at the whole body, muscle, and cellular level. Potential pathways involved in cancer-induced alterations in metabolism and mitochondrial function were explored by interrogating skeletal muscle and plasma metabolomes. Despite similar lean mass compared with control participants, patients with cancer exhibited reduced habitual physical activity (57% fewer daily steps), cardiorespiratory fitness [22% lower V̇o_2peak (mL/kg/min)] and leg strength (35% lower isokinetic knee extensor strength), and greater leg neuromuscular fatigue (36% greater decline in knee extensor torque). Concomitant with these functional declines, patients with cancer had lower mitochondrial oxidative capacity [25% lower State 3 O₂ flux (pmol/s/mg tissue)] and ATP production [23% lower State 3 ATP production (pmol/s/mg tissue)] and alterations in phospholipid metabolite profiles indicative of mitochondrial abnormalities. Whole body protein turnover was unchanged. These findings demonstrate mitochondrial abnormalities concomitant with whole body and skeletal muscle functional derangements associated with human cancer, supporting future work studying the role of mitochondria in the muscle deficits associated with cancer.NEW & NOTEWORTHY To our knowledge, this is the first study to suggest that skeletal muscle mitochondrial deficits are associated with cancer-associated weight loss in humans. Mitochondrial deficits were concurrent with reductions in whole body and skeletal muscle functional capacity. Whether mitochondrial deficits are causal or secondary to cancer-associated weight loss and functional deficits remains to be determined, but this study supports further exploration of mitochondria as a driver of cancer-associated losses in muscle mass and function.

Cachectic muscle wasting in acute myeloid leukaemia: a sleeping giant with dire clinical consequences

Acute myeloid leukaemia (AML) is a haematological malignancy with poor survival odds, particularly in the older (>65 years) population, in whom it is most prevalent. Treatment consists of induction and consolidation chemotherapy to remit the cancer followed by potentially curative haematopoietic cell transplantation. These intense treatments are debilitating and increase the risk of mortality. Patient stratification is used to mitigate this risk and considers a variety of factors, including body mass, to determine whether a patient is suitable for any or all treatment options. Skeletal muscle mass, the primary constituent of the body lean mass, may be a better predictor of patient suitability for, and outcomes of, AML treatment. Yet skeletal muscle is compromised by a variety of factors associated with AML and its clinical treatment consistent with cachexia, a life-threatening body wasting syndrome. Cachectic muscle wasting is associated with both cancer and anticancer chemotherapy. Although not traditionally associated with haematological cancers, cachexia is observed in AML and can have dire consequences. In this review, we discuss the importance of addressing skeletal muscle mass and cachexia within the AML clinical landscape in view of improving survivability of this disease.

A Blueprint for Cancer-Related Inflammation and Host Innate Immunity

Both in situ and allograft models of cancer in juvenile and adult Drosophila melanogaster fruit flies offer a powerful means for unravelling cancer gene networks and cancer-host interactions. They can also be used as tools for cost-effective drug discovery and repurposing. Moreover, in situ modeling of emerging tumors makes it possible to address cancer initiating events-a black box in cancer research, tackle the innate antitumor immune responses to incipient preneoplastic cells and recurrent growing tumors, and decipher the initiation and evolution of inflammation. These studies in Drosophila melanogaster can serve as a blueprint for studies in more complex organisms and help in the design of mechanism-based therapies for the individualized treatment of cancer diseases in humans. This review focuses on new discoveries in Drosophila related to the diverse innate immune responses to cancer-related inflammation and the systemic effects that are so detrimental to the host.

Dietary Naringenin Preserves Insulin Sensitivity and Grip Strength and Attenuates Inflammation but Accelerates Weight Loss in a Mouse Model of Cancer Cachexia

SCOPE

Cancer cachexia is characterized by the loss of skeletal muscle resulting in functional impairment, reduced quality of life and mortality. Naringenin, a flavonoid found in citrus fruits, improves insulin sensitivity and reduces inflammation and tumor growth in preclinical models. Therefore, the study hypothesizes that dietary supplementation of naringenin will improve insulin sensitivity, decrease inflammation, slow body weight loss, and delay tumor growth in a mouse model of cancer cachexia.

METHODS AND RESULTS

Mice are fed 2 wt% dietary naringenin before and during initiation of cancer cachexia using inoculated adenocarcinoma-26 cells (C-26). Food intake, body weight, body composition, muscle function, insulin tolerance, and inflammatory status are assessed. Although naringenin-fed tumor-bearing mice exhibit reductions in body weight and food intake earlier than control diet-fed tumor-bearing mice, dietary naringenin is protective against loss of muscle strength, and attenuates the onset of insulin resistance and markers of inflammation.

CONCLUSIONS

Dietary supplementation of naringenin improves multiple aspects of metabolic disturbance and inflammation during cancer cachexia progression in [C-26 tumor-bearing] mice. However, the acceleration of anorexia and weight loss is also observed. These findings emphasize the link between inflammation and insulin resistance as a basis for understanding their roles in the pathogenesis of cancer cachexia.

An Oatp transporter-mediated steroid sink promotes tumor-induced cachexia in Drosophila

Cancer cachexia is associated with many types of tumors and is characterized by a combination of anorexia, loss of body weight, catabolic alterations, and systemic inflammation. We developed a tumor model in Drosophila larvae that causies cachexia-like syndrome, and we found that cachectic larvae show reduced levels of the circulating steroid ecdysone (Ec). Artificially importing Ec in the tumor through the use of the EcI/Oatp74D importer aggravated cachexia, whereas feeding animals with Ec rescued cachectic defects. This suggests that a steroid sink induced by the tumor promotes catabolic alterations in healthy tissues. We found that Oatp33Eb, a member of the Oatp transporter family, is specifically induced in tumors promoting cachexia. The overexpression of Oatp33Eb in noncachectic tumors induced cachexia, whereas its inhibition in cachectic tumors restored circulating Ec and reversed cachectic alterations. Oatp transporters are induced in several types of hormone-dependent tumors, and this result suggests that a similar sink effect could modify hormonal balance in cachectic cancer patients.

Metabolic Biomarkers for the Early Detection of Cancer Cachexia

Background: Cancer cachexia is a severe metabolic disorder characterized by progressive weight loss along with a dramatic loss in skeletal muscle and adipose tissue. Like cancer, cachexia progresses in stages starting with pre-cachexia to cachexia and finally to refractory cachexia. In the refractory stage, patients are no longer responsive to therapy and management of weight loss is no longer possible. It is therefore critical to detect cachexia as early as possible. In this study we applied a metabolomics approach to search for early biomarkers of cachexia.

Methods: Multi-platform metabolomics analyses were applied to the murine Colon-26 (C26) model of cachexia. Tumor bearing mice (n = 5) were sacrificed every other day over the 14-day time course and control mice (n = 5) were sacrificed every fourth day starting at day 2. Linear regression modeling of the data yielded metabolic trajectories that were compared with the trajectories of body weight and skeletal muscle loss to look for early biomarkers of cachexia.

Results: Weight loss in the tumor-bearing mice became significant at day 9 as did the loss of tibialis muscle. The loss of muscle in the gastrocnemius and quadriceps was significant at day 7. Reductions in amino acids were among the earliest metabolic biomarkers of cachexia. The earliest change was in methionine at day 4. Significant alterations in acylcarnitines and lipoproteins were also detected several days prior to weight loss.

Conclusion: The results of this study demonstrate that metabolic alterations appear well in advance of observable weight loss. The earliest and most significant alterations were found in amino acids and lipoproteins. Validation of these results in other models of cachexia and in clinical studies will pave the way for a clinical diagnostic panel for the early detection of cachexia. Such a panel would provide a tremendous advance in cachectic patient management and in the design of clinical trials for new therapeutic interventions.

Tumor-derived MMPs regulate cachexia in a Drosophila cancer model

Cachexia, the wasting syndrome commonly observed in advanced cancer patients, accounts for up to one-third of cancer-related mortalities. We have established a Drosophila larval model of organ wasting whereby epithelial overgrowth in eye-antennal discs leads to wasting of the adipose tissue and muscles. The wasting is associated with fat-body remodeling and muscle detachment and is dependent on tumor-secreted matrix metalloproteinase 1 (Mmp1). Mmp1 can both modulate TGFβ signaling in the fat body and disrupt basement membrane (BM)/extracellular matrix (ECM) protein localization in both the fat body and the muscle. Inhibition of TGFβ signaling or Mmps in the fat body/muscle using a QF2-QUAS binary expression system rescues muscle wasting in the presence of tumor. Altogether, our study proposes that tumor-derived Mmps are central mediators of organ wasting in cancer cachexia.

Experimental models of lipid overload and their relevance in understanding skeletal muscle insulin resistance and pathological changes in mitochondrial oxidative capacity

It remains essential to decipher some of the pathological mechanisms that link obesity with deteriorating human health. Insulin resistance, due to enhanced free fatty acid substrate delivery, results in disrupted glucose homeostasis and altered mitochondrial oxidative capacity, which is a characteristic feature of an obese state. In fact, as a major site for regulating glucose homeostasis and energy production in response to insulin, the skeletal muscle has become an interesting target tissue to understand the impact of lipid overload on the development of insulin resistance and impaired mitochondrial respiratory function. In addition to systematically retrieving the discussed data, the current review brings an essential perspective in understanding the relevance of experimental models of lipid overload such as high fat diets in understanding the pathological link between insulin resistance and pathological changes in mitochondrial oxidative capacity. Importantly, inclusion of evidence from transgenic model highlights some of the unique molecular targets that are implicated in the development of insulin resistance and inefficient mitochondrial respiration processes within an obese state. Importantly, saturation with lipid products such as ceramides and diacylglycerols, especially within the skeletal muscle, appears to be instrumental in paving the path leading to worsening of metabolic complications. These metabolic consequences mostly interfere with the efficiency of the mitochondrial electron transport chain, leading to overproduction of toxic reactive oxygen species. Therefore, therapeutic agents that reverse the effects of lipid overload by improving insulin sensitivity and mitochondrial oxidative capacity are crucial for the management or even treatment of metabolic diseases.

Metabolic Remodeling in Skeletal Muscle Atrophy as a Therapeutic Target

Skeletal muscle is a highly responsive tissue, able to remodel its size and metabolism in response to external demand. Muscle fibers can vary from fast glycolytic to slow oxidative, and their frequency in a specific muscle is tightly regulated by fiber maturation, innervation, or external causes. Atrophic conditions, including aging, amyotrophic lateral sclerosis, and cancer-induced cachexia, differ in the causative factors and molecular signaling leading to muscle wasting; nevertheless, all of these conditions are characterized by metabolic remodeling, which contributes to the pathological progression of muscle atrophy. Here, we discuss how changes in muscle metabolism can be used as a therapeutic target and review the evidence in support of nutritional interventions and/or physical exercise as tools for counteracting muscle wasting in atrophic conditions.

High glucose: an emerging association between diabetes mellitus and cancer progression

The association of cancer and diabetes mellitus (DM) has been studied for decades. Hyperglycemia and the imbalance of hormones are factors that contribute to the molecular link between DM and carcinogenesis and cancer progression. Hyperglycemia alone or in combination with hyperinsulinemia are key factors that promote cancer aggressiveness. Many preclinical studies suggest that high glucose induces abnormal energy metabolism and aggressive cancer via several mechanisms. As evidenced by clinical studies, hyperglycemia is associated with poor clinical outcomes in patients who have comorbid DM. The prognoses of cancer patients with DM are improved when their plasma glucose levels are controlled. This suggests that high glucose level maybe be involved in the molecular mechanism that causes the link between DM and cancer and may also be useful for prognosis of cancer progression. This review comprehensively summarizes the evidence from recent pre-clinical and clinical studies of the impact of hyperglycemia on cancer advancement as well as the underlying molecular mechanism for this impact. Awareness among clinicians of the association between hyperglycemia or DM and cancer progression may improve cancer treatment outcome in patients who have DM.

Analysis of perioperative glucose metabolism using an artificial pancreas

Hyperglycemia associated with insulin resistance is common in surgical patients with and without diabetes and is associated with poor surgical outcomes. Several studies have recently shown that a closed-loop blood glucose monitoring system in the form of an artificial pancreas is safe and effective for surgical patients. In this study, we analyzed the risk factors for insulin resistance in patients using an artificial pancreas. We investigated 109 patients who underwent surgical management by an artificial pancreas for 24 hours from the start of surgery during either major hepatectomy (MH), defined as resection of more than two liver segments, or pancreaticoduodenectomy (PD). The target glucose range was from 80 to 110 mg/dL using an artificial pancreas. We analyzed the risk factors for and predictors of a high insulin dose, including sarcopenia markers, according to the median 24-hour total insulin infusion. The median total insulin dose and glycemic control rate (GCR), which is the rate of achieving the target blood glucose range, per 24 hours were 78.0 IU and 30.4% in the MH group and 82.6 IU and 23.5% in the PD group, respectively. The muscle volume was the only independent factor in the high-dose subgroup, and the GCR was significantly lower in the high-dose subgroup despite a high insulin dose in both the MH and PD groups. The results of this study suggest that preoperative sarcopenia is closely associated with insulin resistance in the perioperative period. Clinicians must effectively manage sarcopenia, which may result in improved perioperative glycemic control and reduced postoperative complications.

Cancer cachexia: molecular mechanism and pharmacological management

Cancer cachexia often occurs in malignant tumors and is a multifactorial and complex symptom characterized by wasting of skeletal muscle and adipose tissue, resulting in weight loss, poor life quality and shorter survival. The pathogenic mechanism of cancer cachexia is complex, involving a variety of molecular substrates and signal pathways. Advancements in understanding the molecular mechanisms of cancer cachexia have provided a platform for the development of new targeted therapies. Although recent outcomes of early-phase trials have showed that several drugs presented an ideal curative effect, monotherapy cannot be entirely satisfactory in the treatment of cachexia-associated symptoms due to its complex and multifactorial pathogenesis. Therefore, the lack of definitive therapeutic strategies for cancer cachexia emphasizes the need to develop a better understanding of the underlying mechanisms. Increasing evidences show that the progression of cachexia is associated with metabolic alternations, which mainly include excessive energy expenditure, increased proteolysis and mitochondrial dysfunction. In this review, we provided an overview of the key mechanisms of cancer cachexia, with a major focus on muscle atrophy, adipose tissue wasting, anorexia and fatigue and updated the latest progress of pharmacological management of cancer cachexia, thereby further advancing the interventions that can counteract cancer cachexia.

Gut microbiota and metabolic aspects of cancer cachexia

Cancer cachexia is a metabolic syndrome characterized by unintended weight loss and muscle wasting. It has a strong negative impact on survival. Its underlying mechanisms involve systemic inflammation and insulin resistance, which are known to be influenced by the gut microbiota. Preclinical studies support a role for the gut microbiota in cancer cachexia by demonstrating that cachectic mice display: 1) various gut microbiota composition changes; 2) increased gut permeability and translocation of pro-inflammatory microbial compounds; 3) muscle atrophy-related processes linked to gut microbiota properties; 4) positive effects of microbiota-modulating interventions. Data on the relationships between gut microbiota, insulin resistance, and hepatic/adipose tissue metabolism in cachexia models are lacking. Nevertheless, the available data and existing evidence for the impact of gut microbiota on metabolic aberrations in human obesity urge for exploration of its role in human cancer cachexia. We provide practical recommendations and discuss the challenges for such future clinical studies.

Synthesis, Optimization, and Biological Evaluation of Corrinated Conjugates of the GLP-1R Agonist Exendin-4

Corrination is the conjugation of a corrin ring containing molecule, such as vitamin B₁₂ (B12) or B12 biosynthetic precursor dicyanocobinamide (Cbi), to small molecules, peptides, or proteins with the goal of modifying pharmacology. Recently, a corrinated GLP-1R agonist (GLP-1RA) exendin-4 (Ex4) has been shown in vivo to have reduced penetration into the central nervous system relative to Ex4 alone, producing a glucoregulatory GLP-1RA devoid of anorexia and emesis. The study herein was designed to optimize the lead conjugate for GLP-1R agonism and binding. Two specific conjugation sites were introduced in Ex4, while also utilizing various linkers, so that it was possible to identify Cbi conjugates of Ex4 that exhibit improved binding and agonist activity at the GLP-1R. An optimized conjugate (22), comparable with Ex4, was successfully screened and subsequently assayed for insulin secretion in rat islets and in vivo in shrews for glucoregulatory and emetic behavior, relative to Ex4.

Economic burden of diabetes among medicare beneficiaries with cancer

Objectives

Older adults are commonly affected by cancer and diabetes, and an investigation of the economic burden faced by these older adults remains a research gap. Therefore, the objective was to assess the economic burden of diabetes among Medicare beneficiaries with cancer by analyzing annual costs from administrative claims data.

Methods

We conducted a retrospective, serial cross-sectional study using the Medicare Current Beneficiary Survey (MCBS) from 2006 to 2012. Eligible beneficiaries must be currently or previously diagnosed with cancer (of any type), ≥65 years of age, non-institutionalized and continuously enrolled annually in Medicare Parts A, B and D. Diagnoses of cancer and diabetes were determined through self-report or claims. The primary outcome was the total economic burden of diabetes per capita annually, operationalized as the difference in total direct costs between cancer patients with and without diabetes. Simple linear regression was used to analyze trends of costs across the years. Multivariable regression estimated the effect of diabetes and covariates on total annual spending among beneficiaries with cancer from 2006-2012.

Key findings

From 2006 to 2012, 4918 beneficiaries included in MCBS had cancer, with over 25% (1275) also having diabetes. From 2006 to 2012, the mean economic burden of diabetes was $7815 per capita annually. After adjusting for covariates, beginning in 2006, diagnosis of diabetes significantly predicted higher total annual spending among cancer beneficiaries in 2007 [coefficient (SE) = 0.5768 (0.1918), P = 0.003], 2011 [coefficient (SE) = 0.4303 (0.1817), P = 0.018] and 2012 [coefficient (SE) = 0.3605 (0.1758), P = 0.040].

Conclusions

Medicare beneficiaries with cancer experienced a higher economic burden from concurrent diabetes.

Polarization of Macrophages in Insects: Opening Gates for Immuno-Metabolic Research

Insulin resistance and cachexia represent severe metabolic syndromes accompanying a variety of human pathological states, from life-threatening cancer and sepsis to chronic inflammatory states, such as obesity and autoimmune disorders. Although the origin of these metabolic syndromes has not been fully comprehended yet, a growing body of evidence indicates their possible interconnection with the acute and chronic activation of an innate immune response. Current progress in insect immuno-metabolic research reveals that the induction of insulin resistance might represent an adaptive mechanism during the acute phase of bacterial infection. In Drosophila, insulin resistance is induced by signaling factors released by bactericidal macrophages as a reflection of their metabolic polarization toward aerobic glycolysis. Such metabolic adaptation enables them to combat the invading pathogens efficiently but also makes them highly nutritionally demanding. Therefore, systemic metabolism has to be adjusted upon macrophage activation to provide them with nutrients and thus support the immune function. That anticipates the involvement of macrophage-derived systemic factors mediating the inter-organ signaling between macrophages and central energy-storing organs. Although it is crucial to coordinate the macrophage cellular metabolism with systemic metabolic changes during the acute phase of bacterial infection, the action of macrophage-derived factors may become maladaptive if chronic or in case of infection by an intracellular pathogen. We hypothesize that insulin resistance evoked by macrophage-derived signaling factors represents an adaptive mechanism for the mobilization of sources and their preferential delivery toward the activated immune system. We consider here the validity of the presented model for mammals and human medicine. The adoption of aerobic glycolysis by bactericidal macrophages as well as the induction of insulin resistance by macrophage-derived factors are conserved between insects and mammals. Chronic insulin resistance is at the base of many human metabolically conditioned diseases such as non-alcoholic steatohepatitis, atherosclerosis, diabetes, and cachexia. Therefore, revealing the original biological relevance of cytokine-induced insulin resistance may help to develop a suitable strategy for treating these frequent diseases.

Metabolic Aspects of Anthracycline Cardiotoxicity

OPINION STATEMENT

Heart failure (HF) is increasingly recognized as the major complication of chemotherapy regimens. Despite the development of modern targeted therapies such as monoclonal antibodies, doxorubicin (DOXO), one of the most cardiotoxic anticancer agents, still remains the treatment of choice for several solid and hematological tumors. The insurgence of cardiotoxicity represents the major limitation to the clinical use of this potent anticancer drug. At the molecular level, cardiac side effects of DOXO have been associated to mitochondrial dysfunction, DNA damage, impairment of iron metabolism, apoptosis, and autophagy dysregulation. On these bases, the antioxidant and iron chelator molecule, dexrazoxane, currently represents the unique FDA-approved cardioprotectant for patients treated with anthracyclines.A less explored area of research concerns the impact of DOXO on cardiac metabolism. Recent metabolomic studies highlight the possibility that cardiac metabolic alterations may critically contribute to the development of DOXO cardiotoxicity. Among these, the impairment of oxidative phosphorylation and the persistent activation of glycolysis, which are commonly observed in response to DOXO treatment, may undermine the ability of cardiomyocytes to meet the energy demand, eventually leading to energetic failure. Moreover, increasing evidence links DOXO cardiotoxicity to imbalanced insulin signaling and to cardiac insulin resistance. Although anti-diabetic drugs, such as empagliflozin and metformin, have shown interesting cardioprotective effects in vitro and in vivo in different models of heart failure, their mechanism of action is unclear, and their use for the treatment of DOXO cardiotoxicity is still unexplored.This review article aims at summarizing current evidence of the metabolic derangements induced by DOXO and at providing speculations on how key players of cardiac metabolism could be pharmacologically targeted to prevent or cure DOXO cardiomyopathy.

Inflammation, pressure ulcers and poor functional status predict negative rehabilitation outcomes in postacute geriatric patients

The purposes of this retrospective study were to document the prevalence of serum C-reactive protein (CRP), a biomarker of inflammation, and its potential predictive value for Rehabilitation outcomes in post-acute elderly inpatients. The medical records of 304 elderly subjects admitted to our Rehabilitation Institute for any disease following an acute event were examined. High levels of CRP (> 0.5 mg/dl) were present in 100% of the subjects, and the value > 1.5 mg/dl (n = 86) predicted unfavourable outcomes (n = 28; 32.5% of the patients: death or transfer to other institutions). Among the patients with favourable outcomes (discharge home n = 255), 62.7% still exhibited severe disabilities. Pressure ulcers and low functional status also predicted unfavourable outcomes. The study highlights the need for future investigations into the possible reduction of CRP levels, after an intensive nutritional approach and combined physical interventions.