Sisters acts: converging signaling between CaMKII and CaMKIV, two members of the same family

Calcium (Ca2+ ) is a universal second messenger that regulates a number of diverse cellular processes including cell proliferation, development, motility, secretion, learning and memory1, 2. A variety of stimuli, such as hormones, growth factors, cytokines, and neurotransmitters induce changes in the intracellular levels of Ca2+. The most ubiquitous and abundant protein that serves as a receptor to sense changes in Ca2+ concentrations is Calmodulin (CaM), thus mediating the role as second messenger of this ion. The Ca2+/CaM complex initiates a plethora of signaling cascades that culminate in alteration of cell functions. Among the many Ca2+/CaM binding proteins, the multifunctional protein kinases CaMKII and CaMKIV play pivotal roles in the cell

Insulin stimulates fibroblast proliferation through calcium-calmodulin-dependent kinase II.

Insulin effects are mediated by multiple integrated signals generated by the insulin receptor. Fibroblasts, as most of mammalian cells, are a target of insulin action and are impor- tant actors in the vascular pathogenesis of hyperinsulinemia. A role for calcium-calmodulin-dependent kinases (CaMK) in insulin signaling has been proposed but has been under inves- tigated. We investigated the role of the CaMK isoform II in insulin signaling in human fibroblasts. A rapid and transient increase of intracellular calcium concentration was induced by insulin stimulation, followed by increase of CaMKII activity, via L type calcium channels. Concomitantly, insulin stimula- tion induced Raf-1 and ERK activation, followed by thymidine uptake. Inhibition of CaMKII abrogated the insulin-induced Raf-1 and ERK activation, resulting also in the inhibition of thymidine incorporation. These results demonstrate that in fibroblasts, insulin-activated CaMKII is necessary, together with Raf-1, for ERK activation and cell proliferation. This represents a novel mechanism in the control of insulin signals leading to fibroblast proliferation, as well as a putative site for pharmacological intervention

Insulin stimulates fibroblast proliferation through calcium-calmodulin-dependent kinase II.

Insulin effects are mediated by multiple integrated signals generated by the insulin receptor. Fibroblasts, as most of mammalian cells, are a target of insulin action and are impor- tant actors in the vascular pathogenesis of hyperinsulinemia. A role for calcium-calmodulin-dependent kinases (CaMK) in insulin signaling has been proposed but has been under inves- tigated. We investigated the role of the CaMK isoform II in insulin signaling in human fibroblasts. A rapid and transient increase of intracellular calcium concentration was induced by insulin stimulation, followed by increase of CaMKII activity, via L type calcium channels. Concomitantly, insulin stimula- tion induced Raf-1 and ERK activation, followed by thymidine uptake. Inhibition of CaMKII abrogated the insulin-induced Raf-1 and ERK activation, resulting also in the inhibition of thymidine incorporation. These results demonstrate that in fibroblasts, insulin-activated CaMKII is necessary, together with Raf-1, for ERK activation and cell proliferation. This represents a novel mechanism in the control of insulin signals leading to fibroblast proliferation, as well as a putative site for pharmacological intervention

A novel crosstalk between calcium/calmodulin kinases II and IV regulates cell proliferation in myeloid leukemia cells

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NutriLive: An Integrated Nutritional Approach as a Sustainable Tool to Prevent Malnutrition in Older People and Promote Active and Healthy Ageing—The EIP-AHA Nutrition Action Group

The present document describes a nutritional approach that is nested in the European Innovation Partnership for Active and Healthy Aging (EIP-AHA) and aims to provide the first common European program translating an integrated approach to nutritional frailty in terms of a multidimensional and transnational methodology. The document has been developed by the A3 Nutrition Action Area of the EIP-AHA and aims at providing a stepwise approach to malnutrition in older citizens, identifying adequate interventions based on a unified assessment and ICT-supported solutions. "NutriLive" is an integrated nutritional approach, represented by a structured Screening-Assessment-Monitoring-Action-Pyramid-Model (SAM-AP). Its core concept is the stratification of the nutritional needs, considered by the working group as the key for targeted, effective, and sustainable interventions. "NutriLive" tries to close gaps in epidemiological data within an aging population, creating a unified language to deal with the topic of nutrition and malnutrition in Europe. By assembling all the validated screening, assessment, and monitoring tools on malnutrition in a first pyramid, which is interrelated to a second intervention pyramid, the A3 Nutrition WG identifies a common, integrated vision on the nutritional approach to frailty, which applies to the various health care settings

Cellular subtype expression and activation of CaMKII regulate the fate of atherosclerotic plaque

Abstract Background and aims Atherosclerosis is a degenerative process of the arterial wall implicating activation of macrophages and proliferation of vascular smooth muscle cells. Calcium-calmodulin dependent kinase type II (CaMKII) in vascular smooth muscle cells (VSMCs) regulates proliferation, while in macrophages, this kinase governs diapedesis, infiltration and release of extracellular matrix enzymes. We aimed at understanding the possible role of CaMKII in atherosclerosis plaques to regulate plaque evolution towards stability or instability. Methods Clinically defined stable and unstable plaques obtained from patients undergoing carotid end arteriectomy were processed for evaluation of CaMKs protein expression, activity and localization. Results The larger content of CaMKII was found in CD14 + myeloid cells that were more abundant in unstable rather than stable plaques. To test the biological effect of activated CD14 + myeloid cells, VSMCs were exposed to the conditioned medium (CM) of macrophages extracted from carotid plaques. CM induced attenuation of CaMKs expression and activity in VSMCs, leading to the reduction of VSMCs proliferation. This appears to be due to the CaMKII dependent release of cytokines. Conclusions These results indicate a pivotal role of CaMKs in atherosclerosis by regulating activated myeloid cells on VSMCs activity. CaMKII could represent a possible target for therapeutic strategies based on macrophages specific inhibition for the stabilization of arteriosclerotic lesions

Targeting the CaMKII/ERK Interaction in the Heart Prevents Cardiac Hypertrophy

AIMS: Activation of Ca2+/Calmodulin protein kinase II (CaMKII) is an important step in signaling of cardiac hypertrophy. The molecular mechanisms by which CaMKII integrates with other pathways in the heart are incompletely understood. We hypothesize that CaMKII association with extracellular regulated kinase (ERK), promotes cardiac hypertrophy through ERK nuclear localization. METHODS AND RESULTS: In H9C2 cardiomyoblasts, the selective CaMKII peptide inhibitor AntCaNtide, its penetratin conjugated minimal inhibitory sequence analog tat-CN17β, and the MEK/ERK inhibitor UO126 all reduce phenylephrine (PE)-mediated ERK and CaMKII activation and their interaction. Moreover, AntCaNtide or tat-CN17β pretreatment prevented PE induced CaMKII and ERK nuclear accumulation in H9C2s and reduced the hypertrophy responses. To determine the role of CaMKII in cardiac hypertrophy in vivo, spontaneously hypertensive rats were subjected to intramyocardial injections of AntCaNtide or tat-CN17β. Left ventricular hypertrophy was evaluated weekly for 3 weeks by cardiac ultrasounds. We observed that the treatment with CaMKII inhibitors induced similar but significant reduction of cardiac size, left ventricular mass, and thickness of cardiac wall. The treatment with CaMKII inhibitors caused a significant reduction of CaMKII and ERK phosphorylation levels and their nuclear localization in the heart. CONCLUSION: These results indicate that CaMKII and ERK interact to promote activation in hypertrophy; the inhibition of CaMKII-ERK interaction offers a novel therapeutic approach to limit cardiac hypertrophy

Metabolic Syndrome and Aging: Calcium Signaling as Common Regulator

Aging is one of the most important societal challenges that western societies face, as a result of longer life expectancy and reduced natality rates. Aging is a success story of our health and social systems, but raises sustainability issues that are linked to the increased need for services of older adults, due to the reduction of their independence and to the co-existence of multiple chronic diseases. The metabolic syndrome can be considered an age-related disease, since its prevalence increases with age. Current demographic trends in the population highlight aging-related dysfunctions that contribute to the onset of several metabolic diseases, and the need for innovative, effective and sustainable approaches. This review describes the correlation between the metabolic syndrome and aging, and the underlying common molecular mechanisms, focusing on calcium signaling and its crosstalks

Cross-Talk between Neurohormonal Pathways and the Immune System in Heart Failure: A Review of the Literature

Heart failure is a complex clinical syndrome involving a multitude of neurohormonal pathways including the renin-angiotensin-aldosterone system, sympathetic nervous system, and natriuretic peptides system. It is now emerging that neurohumoral mechanisms activated during heart failure, with both preserved and reduced ejection fraction, modulate cells of the immune system. Indeed, these cells express angiotensin I receptors, adrenoceptors, and natriuretic peptides receptors. Ang II modulates macrophage polarization, promoting M2 macrophages phenotype, and this stimulation can influence lymphocytes Th1/Th2 balance. -AR activation in monocytes is responsible for inhibition of free oxygen radicals production, and together with 2-AR can modulate TNF- receptor expression and TNF- release. In dendritic cells, activation of 2-AR inhibits IL-12 production, resulting in the inhibition of Th1 and promotion of Th2 differentiation. ANP induces the activation of secretion of superoxide anion in polymorphonucleated cells; reduces TNF- and nitric oxide secretion in macrophages; and attenuates the exacerbated TH1 responses. BNP in macrophages can stimulate ROS production, up-regulates IL-10, and inhibits IL-12 and TNF- release by dendritic cells, suggesting an anti-inflammatory cytokines profile induction. Therefore, different neurohormonal-immune cross-talks can determine the phenotype of cardiac remodeling, promoting either favorable or maladaptive responses. This review aims to summarize the available knowledge on neurohormonal modulation of immune responses, providing supportive rational background for further research