Sympathetic overactivation predicts body weight loss in patients with heart failure

Neural Circuits Underlying Reciprocal Cardiometabolic Crosstalk: 2023 Arthur C. Corcoran Memorial Lecture

The interplay of various body systems, encompassing those that govern cardiovascular and metabolic functions, has evolved alongside the development of multicellular organisms. This evolutionary process is essential for the coordination and maintenance of homeostasis and overall health by facilitating the adaptation of the organism to internal and external cues. Disruption of these complex interactions contributes to the development and progression of pathologies that involve multiple organs. Obesity-associated cardiovascular risks, such as hypertension, highlight the significant influence that metabolic processes exert on the cardiovascular system. This cardiometabolic communication is reciprocal, as indicated by substantial evidence pointing to the ability of the cardiovascular system to affect metabolic processes, with pathophysiological implications in disease conditions. In this review, I outline the bidirectional nature of the cardiometabolic interaction, with special emphasis on the impact that metabolic organs have on the cardiovascular system. I also discuss the contribution of the neural circuits and autonomic nervous system in mediating the crosstalk between cardiovascular and metabolic functions in health and disease, along with the molecular mechanisms involved.

Association of weight loss with cardiovascular or all-cause mortality in patients with heart failure: A meta-analysis

BACKGROUND

A consensus has not been reached on the association between weight loss and survival outcomes in patients with heart failure (HF). This meta-analysis aimed to assess the association of weight loss with cardiovascular or all-cause mortality in patients with HF.

METHODS

Two authors independently searched the articles indexed in the PubMed and Embase databases up to May 7, 2023. Post hoc analysis of randomized controlled trials or observational studies that reported the utility of weight loss in predicting cardiovascular or all-cause mortality in patients with HF were included.

RESULTS

Thirteen studies reporting on 12 articles involving 26,164 patients with HF were included. A comparison of weight loss with stable weight showed that the pooled adjusted hazard ratio (HR) for all-cause mortality was 1.75 (95% confidence intervals [CI] 1.43-2.14). Subgroup analysis revealed that weight loss was associated with an increased risk of all-cause mortality, irrespective of whether patients were overweight/obese (HR 1.76; 95% CI 1.41-2.20) or not (HR 1.90; 95% CI 1.14-3.14). The pooled adjusted HR of cardiovascular mortality was 1.64 (95% CI 1.18-2.28) for patients with weight loss compared to those without.

CONCLUSIONS

Weight loss is associated with an increased risk of cardiovascular and all-cause mortality in patients with HF. Assessing weight changes can provide prognostic information for patients with HF.

Weight fluctuations preceding and succeeding heart failure diagnosis: Implications for all-cause mortality

OBJECTIVE

This study aims to explore the ramifications of weight fluctuations preceding and succeeding the identification of heart failure (HF) on all-cause mortality.

METHODS

The research cohort comprised individuals engaged in the Kailuan Group's health assessments from 2006 to 2018, who were subsequently diagnosed with HF. The moment of HF recognition marked the commencement of the monitoring period, culminating either at the instance of comprehensive mortality or at the conclusion of the monitoring phase (December 31, 2021).

RESULTS

Throughout an average monitoring span of 5.8±3.5 years, from the 3115 qualified participants, 957 instances (30.7%) encountered comprehensive mortality. The COX proportional hazards regression model's outcomes revealed that, post the adjustment for potential confounders, in comparison to the Q3 category, the Q1 category had the highest hazard ratios (95% confidence intervals) of 1.71 (1.43-2.05).

CONCLUSION

Weight reduction before and post the HF diagnosis stands as an autonomous risk determinant for comprehensive mortality.

Astragalus polysaccharide prevents heart failure-induced cachexia by alleviating excessive adipose expenditure in white and brown adipose tissue

BACKGROUND

Astragalus polysaccharide (APS) is a key active ingredient isolated from Astragalus membranaceus that has been reported to be a potential treatment for obesity and diabetes by regulating lipid metabolism and adipogenesis, alleviating inflammation, and improving insulin resistance. However, whether APS regulates lipid metabolism in the context of cachexia remains unclear. Therefore, this study analysed the effects of APS on lipid metabolism and adipose expenditure in a heart failure (HF)-induced cardiac cachexia rat model.  METHODS: A salt-sensitive hypertension-induced cardiac cachexia rat model was used in the present study. Cardiac function was detected by echocardiography. The histological features and fat droplets in fat tissue and liver were observed by H&E staining and Oil O Red staining. Immunohistochemical staining, Western blotting and RT‒qPCR were used to detect markers of lipolysis and adipose browning in white adipose tissue (WAT) and thermogenesis in brown adipose tissue (BAT). Additionally, sympathetic nerve activity and inflammation in adipose tissue were detected.

RESULTS

Rats with HF exhibited decreased cardiac function and reduced adipose accumulation as well as adipocyte atrophy. In contrast, administration of APS not only improved cardiac function and increased adipose weight but also prevented adipose atrophy and FFA efflux in HF-induced cachexia. Moreover, APS inhibited HF-induced lipolysis and browning of white adipocytes since the expression levels of lipid droplet enzymes, including HSL and perilipin, and beige adipocyte markers, including UCP-1, Cd137 and Zic-1, were suppressed after administration of APS. In BAT, treatment with APS inhibited PKA-p38 MAPK signalling, and these effects were accompanied by decreased thermogenesis reflected by decreased expression of UCP-1, PPAR-γ and PGC-1α and reduced FFA β-oxidation in mitochondria reflected by decreased Cd36, Fatp-1 and Cpt1. Moreover, sympathetic nerve activity and interleukin-6 levels were abnormally elevated in HF rats, and astragalus polysaccharide could inhibit their activity.

CONCLUSION

APS prevented lipolysis and adipose browning in WAT and decreased BAT thermogenesis. These effects may be related to suppressed sympathetic activity and inflammation. This study provides a potential approach to treat HF-induced cardiac cachexia.

α1-Adrenergic Stimulation Increases Platelet Adhesion to Endothelial Cells Mediated by TRPC6

Stimulation of a1-adrenergic nervous system is increased during systemic inflammation and other pathological conditions with the consequent adrenergic receptors (ARs) activation. It has been reported that a1-stimulation contributes to coagulation since a1-AR blockers inhibit coagulation and its organic consequences. Also, coagulation induced by a1-AR stimulation can be greatly decreased using a1-AR blockers. In health, endothelial cells (ECs) perform anticoagulant actions at cellular and molecular level. However, during inflammation, ECs turn dysfunctional promoting a procoagulant state. Endothelium-dependent coagulation progresses at cellular and molecular levels, promoting endothelial acquisition of procoagulant properties to potentiate coagulation by means of prothrombotic and antifibrinolytic proteins expression increase in ECs releasing them to circulation, the thrombus formation is strengthened. Calcium signaling is a main feature of coagulation. Inhibition of ion channels involved in Ca²⁺ entry severely decreases coagulation. The transient receptor potential canonical 6 (TRPC6) is a non-selective Ca²⁺-permeable ion channel. TRPC6 activity is induced by diacylglycerol, suggesting that is regulated by a1-ARs. Furthermore, a1-ARs stimulation elicits a TRPC-like current in rat mesenteric artery smooth muscle and mesangial cells. However, whether TRPC6 could promote an ECs-mediated platelet adhesion induced by a1-adrenergic stimulation is currently not known. Therefore, the aim of this study was to examine if the TRPC6 calcium channel mediates platelet adhesion induced by a1-adrenergic stimulation. Our results suggest that platelet adhesion to ECs is enhanced by the a1-adrenergic stimulation evoked by phenylephrine mediated by TRPC6 activity. We conclude that TRPC6 is a molecular determinant in platelet adhesion to ECs with implications in systemic inflammatory diseases treatment.