Cardiac Cachexia: Unaddressed Aspect in Cancer Patients

Blood Circulating LncRNAs: SNHG5 and ZFAS1 as Biomarkers Reflecting Cachexia Incidence in Chronic Heart Failure Patients

BACKGROUND

Systemic inflammation plays a crucial role in the development and progression of chronic heart failure (CHF) across all phenotypes. The continuous release of proinflammatory cytokines causes muscle atrophy and adipocyte breakdown, ultimately resulting in cachexia. Long noncoding RNAs (lncRNAs) are emerging as potential biomarkers associated with cachexia, as they indirectly regulate muscle and fat tissue metabolism.

OBJECTIVES

This study aimed to identify inflammatory-related, plasma-circulating lncRNAs characteristic of cachexia in patients with CHF. The secondary objective was to assess the clinical utility of these selected lncRNAs as diagnostic and predictive markers for cachexia.

METHODS

Blood plasma samples were collected from 157 newly diagnosed patients with CHF (91 males and 66 females; mean age: 72 ± 13 y) for lncRNA extraction. Molecular testing, using RT2 lncRNA qRT-PCR Array Human Cell Development, Differentiation, and Inflammatory Panel was performed in 2 phases: the discovery phase (screening of 148 lncRNAs in 8 patients) and validation phase (validation of the identified lncRNAs in 157 patients).

RESULTS

Five lncRNAs were found to be differentially expressed in the discovery phase. In the validation phase, 2 of these 5 lncRNAs-SNHG5 and ZFAS1-showed significant expression differences between cachectic and noncachectic patients in the entire study group (both P < 0.001). The combined downregulation of ZFAS1 and upregulation of SNHG5 was identified as an unfavorable lncRNA signature primarily associated with poor nutritional status in females (low fat-free mass, fat-free mass index, and body mass index), abnormal laboratory results (hypoalbuminemia and high concentrations of inflammatory markers), and an increased incidence of cachexia in patients with CHF. When this lncRNA signature was combined with serum C-reactive protein and albumin concentrations, it effectively differentiated between cachectic and noncachectic patients (area under the curve = 1.0). The presence of this unfavorable signature was associated with a 9-fold increased likelihood (odds ratio = 9.2) of cachexia in the study cohort.

CONCLUSIONS

The identified lncRNA signature demonstrates potential clinical value for distinguishing and predicting cachexia in patients with CHF.

Withaferin A Attenuates Muscle Cachexia Induced by Angiotensin II Through Regulating Pathways Activated by Angiotensin II

Cachexia is a multifactorial syndrome characterized by severe muscle wasting and is a debilitating condition frequently associated with cancer. Previous studies from our group revealed that withaferin A (WFA), a steroidal lactone, mitigated muscle cachexia induced by ovarian tumors in NSG mice. However, it remains unclear whether WFA's protective effects are direct or secondary to its antitumor properties. We developed a cachectic model through continuous angiotensin II (Ang II) infusion in C57BL/6 mice to address this issue. Ang II infusion resulted in profound muscle atrophy, evidenced by significant reductions in grip strength and in the TA, GA, and GF muscle mass. Molecular analyses indicated elevated expression of inflammatory cytokines (TNFα, IL-6, MIP-2, IL-18, IL-1β), NLRP3 inflammasome, and genes associated with the UPS (MuRF1, MAFBx) and autophagy pathways (Bacl1, LC3B), along with suppression of anti-inflammatory heme oxygenase-1 (HO-1) and myogenic regulators (Pax7, Myod1). Strikingly, WFA treatment reversed these pathological changes, restoring muscle mass, strength, and molecular markers to near-normal levels. These findings demonstrate that WFA exerts direct anti-cachectic effects by targeting key inflammatory and atrophic pathways in skeletal muscle, highlighting its potential as a novel therapeutic agent for cachexia management.

Cardiac wasting in patients with cancer

Patients with cancer face a significant risk of cardiovascular death, regardless of time since cancer diagnosis. Elderly patients are particularly more susceptible as cancer-associated cardiac complications present in advanced stage cancer. These patients may often present with symptoms observed in chronic heart failure (HF). Cardiac wasting, commonly observed in these patients, is a multifaceted syndrome characterized by systemic metabolic alterations and inflammatory processes that specifically affect cardiac function and structure. Experimental and clinical studies have demonstrated that cancer-associated cardiac wasting is linked with cardiac atrophy and altered cardiac morphology, which impairs cardiac function, particularly pertaining to the left ventricle. Therefore, this review aims to present a summary of epidemiologic data and pathophysiological mechanisms of cardiac wasting due to cancer, and future directions in this field.

Cancer cachexia: multilevel metabolic dysfunction

Cancer cachexia is a complex metabolic disorder marked by unintentional body weight loss or 'wasting' of body mass, driven by multiple aetiological factors operating at various levels. It is associated with many malignancies and significantly contributes to cancer-related morbidity and mortality. With emerging recognition of cancer as a systemic disease, there is increasing awareness that understanding and treatment of cancer cachexia may represent a crucial cornerstone for improved management of cancer. Here, we describe the metabolic changes contributing to body wasting in cachexia and explain how the entangled action of both tumour-derived and host-amplified processes induces these metabolic changes. We discuss energy homeostasis and possible ways that the presence of a tumour interferes with or hijacks physiological energy conservation pathways. In that context, we highlight the role played by metabolic cross-talk mechanisms in cachexia pathogenesis. Lastly, we elaborate on the challenges and opportunities in the treatment of this devastating paraneoplastic phenomenon that arise from the complex and multifaceted metabolic cross-talk mechanisms and provide a status on current and emerging therapeutic approaches.

Withaferin A ameliorates ovarian cancer-induced renal damage through the regulation of expression of inflammatory cytokines

BACKGROUND

Cachexia a multifactorial syndrome is a common sequala in patients with cancer. It varies from 42 to 80% depending upon the oncological stage and is directly responsible for 30% of deaths in these patients. Previous research from our laboratory demonstrated that peritoneal ovarian cancer generated in NSG mice resulted in skeletal and cardiac muscle atrophy - leading to loss of skeletal muscle mass and strength, and cardiac dysfunction (cachexia). Treatment of mice bearing i.p. tumors with withaferin A (WFA) showed reversal of skeletal muscle and cardiac cachexia. The present study is focused on determining effects of peritoneal ovarian tumors on kidney damage and effects of WFA treatment on ameliorating kidney damage.

METHODS

We generated intraperitoneal ovarian cancer by injecting female NSG mice with ovarian cancer cell line (A2780). After one week of injecting cancer cells, mice were treated with WFA (4 mg/kg) every third day, for three weeks. After 4 weeks of injection of cancer cells, the mice were sacrificed and various tissues including kidney and blood were collected, snap-frozen in liquid nitrogen, and stored at -800C. The presence of kidney biomarker creatinine, was measured in the plasma by an ELISA. The mRNA was isolated from mouse kidneys and was used to examine the expression levels of signaling proteins, inflammatory cytokines, and genes responsible for inducing cachexia (IL-1β, IL-6, TNF-α, TGF-β, GDF-15, and MYD88).

RESULTS

Our results showed a significant increase in levels of expression of inflammatory cytokine IL-1 β (p < 0.01), IL-6 (p < 0.001), TNF-α (p < 0.001), and other related genes including TRAF6 (p < 0.01), MYD88 (p < 0.01), and GDF-15 (p = 0.005) in tumor-bearing mice compared to controls. Treatment of mice bearing tumors with WFA attenuated the increase in expression of each gene. In addition, our results showed a significant increase in creatinine levels in circulation in tumor-bearing mice compared to control mice. Treatment of tumor-bearing mice with WFA resulted in a significant decrease in plasma creatinine levels compared to tumor-bearing mice.

CONCLUSIONS

Our results conclude that ovarian tumors in NSG mice caused kidney damage and renal dysfunction, which was effectively ameliorated by WFA treatment, suggesting a protective effect of WFA on kidney injury induced by ovarian cancer.

Increased Myocardial MAO-A, Atrogin-1, and IL-1β Expression in Transgenic Mice with Pancreatic Carcinoma-Benefit of MAO-A Inhibition for Cardiac Cachexia

Cancer cachexia (CC) continues to challenge clinicians by massively impairing patients' prognosis, mobility, and quality of life through skeletal muscle wasting. CC also includes cardiac cachexia as characterized by atrophy, compromised metabolism, innervation and function of the myocardium through factors awaiting clarification for therapeutic targeting. Because monoamine oxidase-A (MAO-A) is a myocardial source of H2O2 and implicated in myofibrillar protein catabolism and heart failure, we presently studied myocardial MAO-A expression, inflammatory cells, and capillarization together with transcripts of pro-inflammatory, -angiogenic, -apoptotic, and -proteolytic signals (by qRT-PCR) in a 3x-transgenic (LSL-KrasG12D/+; LSL-TrP53R172H/+; Pdx1-Cre) mouse model of orthotopic pancreatic ductal adenoarcinoma (PDAC) compared to wild-type (WT) mice. Moreover, we evaluated the effect of MAO-A inhibition by application of harmine hydrochloride (HH, 8 weeks, i.p., no sham control) on PDAC-related myocardial alterations. Myocardial MAO-A protein content was significantly increased (1.69-fold) in PDAC compared to WT mice. PDAC was associated with an increased percentage of atrogin-1+ (p < 0.001), IL-1β+ (p < 0.01), COX2+ (p < 0.001), and CD68+ (p > 0.05) cells and enhanced transcripts of pro-inflammatory IL-1β (2.47-fold), COX2 (1.53-fold), TNF (1.87-fold), and SOCS3 (1.64-fold). Moreover, PDAC was associated with a reduction in capillary density (-17%, p < 0.05) and transcripts of KDR (0.46-fold) but not of VEGFA, Notch1, or Notch3. Importantly, HH treatment largely reversed the PDAC-related increases in atrogin-1+, IL-1β+, and TNF+ cell fraction as well as in COX2, IL-1β, TNF, and SOCS3 transcripts, whereas capillary density and KDR transcripts failed to improve. In mice with PDAC, increased myocardial pro-atrophic/-inflammatory signals are attributable to increased expression of MAO-A, because they are significantly improved with MAO-A inhibition as a potential novel therapeutic option. The PDAC-related loss in myocardial capillary density may be due to other mechanisms awaiting evaluation with consideration of cardiomyocyte size, cardiac function and physical activity.

Therapy-naïve malignancy causes cardiovascular disease: a state-of-the-art cardio-oncology perspective

Cardiovascular disease (CVD) and cancer are the leading causes of mortality worldwide. Although generally thought of as distinct diseases, the intersectional overlap between CVD and cancer is increasingly evident in both causal and mechanistic relationships. The field of cardio-oncology is largely focused on the cardiotoxic effects of cancer therapies (e.g., chemotherapy, radiation). Furthermore, the cumulative effects of cardiotoxic therapy exposure and the prevalence of CVD risk factors in patients with cancer lead to long-term morbidity and poor quality of life in this patient population, even when patients are cancer-free. Evidence from patients with cancer and animal models demonstrates that the presence of malignancy itself, independent of cardiotoxic therapy exposure or CVD risk factors, negatively impacts cardiac structure and function. As such, the primary focus of this review is the cardiac pathophysiological and molecular features of therapy-naïve cancer. We also summarize the strengths and limitations of preclinical cancer models for cardio-oncology research and discuss therapeutic strategies that have been tested experimentally for the treatment of cancer-induced cardiac atrophy and dysfunction. Finally, we explore an adjacent area of interest, called "reverse cardio-oncology," where the sequelae of heart failure augment cancer progression. Here, we emphasize the cross-disease communication between malignancy and the injured heart and discuss the importance of chronic low-grade inflammation and endocrine factors in the progression of both diseases.

Withaferin A as a Potential Therapeutic Target for the Treatment of Angiotensin II-Induced Cardiac Cachexia

In our previous studies, we showed that the generation of ovarian tumors in NSG mice (immune-compromised) resulted in the induction of muscle and cardiac cachexia, and treatment with withaferin A (WFA; a steroidal lactone) attenuated both muscle and cardiac cachexia. However, our studies could not address if these restorations by WFA were mediated by its anti-tumorigenic properties that might, in turn, reduce the tumor burden or WFA's direct, inherent anti-cachectic properties. To address this important issue, in our present study, we used a cachectic model induced by the continuous infusion of Ang II by implanting osmotic pumps in immunocompetent C57BL/6 mice. The continuous infusion of Ang II resulted in the loss of the normal functions of the left ventricle (LV) (both systolic and diastolic), including a significant reduction in fractional shortening, an increase in heart weight and LV wall thickness, and the development of cardiac hypertrophy. The infusion of Ang II also resulted in the development of cardiac fibrosis, and significant increases in the expression levels of genes (ANP, BNP, and MHCβ) associated with cardiac hypertrophy and the chemical staining of the collagen abundance as an indication of fibrosis. In addition, Ang II caused a significant increase in expression levels of inflammatory cytokines (IL-6, IL-17, MIP-2, and IFNγ), NLRP3 inflammasomes, AT1 receptor, and a decrease in AT2 receptor. Treatment with WFA rescued the LV functions and heart hypertrophy and fibrosis. Our results demonstrated, for the first time, that, while WFA has anti-tumorigenic properties, it also ameliorates the cardiac dysfunction induced by Ang II, suggesting that it could be an anticachectic agent that induces direct effects on cardiac muscles.

Highlighting the idea of exerkines in the management of cancer patients with cachexia: novel insights and a critical review

BACKGROUND

Exerkines are all peptides, metabolites, and nucleic acids released into the bloodstream during and after physical exercise. Exerkines liberated from skeletal muscle (myokines), the heart (cardiokines), liver (hepatokines), white adipose tissue (adipokines), brown adipose tissue (batokines), and neurons (neurokines) may benefit health and wellbeing. Cancer-related cachexia is a highly prevalent disorder characterized by weight loss with specific skeletal muscle and adipose tissue loss. Many studies have sought to provide exercise strategies for managing cachexia, focusing on musculoskeletal tissue changes. Therefore, understanding the responses of musculoskeletal and other tissue exerkines to acute and chronic exercise may provide novel insight and recommendations for physical training to counteract cancer-related cachexia.

METHODS

For the purpose of conducting this study review, we made efforts to gather relevant studies and thoroughly discuss them to create a comprehensive overview. To achieve this, we conducted searches using appropriate keywords in various databases. Studies that were deemed irrelevant to the current research, not available in English, or lacking full-text access were excluded. Nevertheless, it is important to acknowledge the limited amount of research conducted in this specific field.

RESULTS

In order to obtain a comprehensive understanding of the findings, we prioritized human studies in order to obtain results that closely align with the scope of the present study. However, in instances where human studies were limited or additional analysis was required to draw more robust conclusions, we also incorporated animal studies. Finally, 295 studies, discussed in this review.

CONCLUSION

Our understanding of the underlying physiological mechanisms related to the significance of investigating exerkines in cancer cachexia is currently quite basic. Nonetheless, this demonstrated that resistance and aerobic exercise can contribute to the reduction and control of the disease in individuals with cancer cachexia, as well as in survivors, by inducing changes in exerkines.

The pathophysiology of cancer-mediated cardiac cachexia and novel treatment strategies: A narrative review

SIGNIFICANCE

Two of the leading causes of death worldwide are cancer and cardiovascular diseases. Most cancer patients suffer from a metabolic wasting syndrome known as cancer-induced cardiac cachexia, resulting in death in up to 30% of cancer patients. Main symptoms of this disease are severe cardiac muscle wasting, cardiac remodeling, and cardiac dysfunction. Metabolic alterations, increased inflammation, and imbalance of protein homeostasis contribute to the progression of this multifactorial syndrome, ultimately resulting in heart failure and death. Cancer-induced cardiac cachexia is associated with decreased quality of life, increased fatiguability, and decreased tolerance to therapeutic interventions.

RECENT ADVANCES

While molecular mechanisms of this disease are not fully understood, researchers have identified different stages of progression of this disease, as well as potential biomarkers to detect and monitor the development. Preclinical and clinical studies have shown positive results when implementing certain pharmacological and non-pharmacological therapy interventions.

CRITICAL ISSUES

There are still no clear diagnostic criteria for cancer-mediated cardiac cachexia and the condition remains untreated, leaving cancer patients with irreversible effects of this syndrome. While traditional cardiovascular therapy interventions, such as beta-blockers, have shown some positive results in preclinical and clinical research studies, recent preclinical studies have shown more successful results with certain non-traditional treatment options that have not been further evaluated yet. There is still no clinical standard of care or approved FDA drug to aid in the prevention or treatment of cancer-induced cardiac cachexia. This review aims to revisit the still not fully understood pathophysiological mechanisms of cancer-induced cardiac cachexia and explore recent studies using novel treatment strategies.

FUTURE DIRECTIONS

While research has progressed, further investigations might provide novel diagnostic techniques, potential biomarkers to monitor the progression of the disease, as well as viable pharmacological and non-pharmacological treatment options to increase quality of life and reduce cancer-induced cardiac cachexia-related mortality.

Cancer cachexia - adopting a systems wide approach

PURPOSE OF REVIEW

Cancer cachexia results in the death of approximately 2 million people worldwide annually. Despite the impact of this devastating condition, there is limited therapy and no standard of care. Although multiple definitions exist, confusion remains as a true understanding of the biology has not yet been achieved and distinct phases of cachexia have not been examined. Research has mainly focused on weight loss and muscle wasting, but cachexia is increasingly recognized as a multiorgan disorder involving adipose tissue, liver, brain, gut and heart, with systemic inflammation a central unifying feature.

RECENT FINDINGS

In this review, we will discuss some of the extra-muscular features and multisystem interactions in cachexia, and describe how moving our focus beyond muscle can lead to a greater understanding of the mechanisms and clinical features seen in cachexia.

SUMMARY

We describe the need for robust characterization of patients with cachexia, to allow clinical phenotypes and multisystem mechanisms to be untangled, and to enable the implementation of multimodal treatment strategies.

The complex pathophysiology of cardiac cachexia: A review of current pathophysiology and implications for clinical practice

Cardiac cachexia is a muscle wasting process that often develops in those with chronic heart failure resulting in weight loss, low levels of physical activity, reduced quality of life, and is associated with a poor prognosis. The pathology of cardiac cachexia is complex with new evidence emerging that implicates several body systems. This review describes the pathophysiology associated with cardiac cachexia and addresses: 1) hormonal changes- neurohormonal abnormalities and metabolic hormone imbalance; 2) mechanisms of muscle wasting in cardiac cachexia, and the integral mechanisms between changed hormones due to cardiac cachexia and muscle wasting processes, and 3) associated abnormalities of gastrointestinal system that contribute to cardiac cachexia. These pleiotropic mechanisms demonstrate the intricate interplay between the affected systems and account for why cardiac cachexia is difficult to manage clinically. This review summarises current pathophysiology of cardiac cachexia and highlights symptoms of cardiac cachexia, implications for clinical practice and research gaps.