Pharmacological implications of the Ca(2+)/cAMP signaling interaction: from risk for antihypertensive therapy to potential beneficial for neurological and psychiatric disorders

Ca2+/cAMP ratio: An inflammatory index for diabetes, hypertension, and COVID-19

Ca²⁺/cAMP ratio could serve as an inflammatory index for diseases like hyp-ertension, diabetes, and coronavirus disease 2019.

Bioinformatics and systems biology approaches to identify the effects of COVID-19 on neurodegenerative diseases: A review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease (COVID-19), has been devastated by COVID-19 in an increasing number of countries and health care systems around the world since its announcement of a global pandemic on 11 March 2020. During the pandemic, emerging novel viral mutant variants have caused multiple outbreaks of COVID-19 around the world and are prone to genetic evolution, causing serious damage to human health. As confirmed cases of COVID-19 spread rapidly, there is evidence that SARS-CoV-2 infection involves the central nervous system (CNS) and peripheral nervous system (PNS), directly or indirectly damaging neurons and further leading to neurodegenerative diseases (ND), but the molecular mechanisms of ND and CVOID-19 are unknown. We employed transcriptomic profiling to detect several major diseases of ND: Alzheimer 's disease (AD), Parkinson' s disease (PD), and multiple sclerosis (MS) common pathways and molecular biomarkers in association with COVID-19, helping to understand the link between ND and COVID-19. There were 14, 30 and 19 differentially expressed genes (DEGs) between COVID-19 and Alzheimer 's disease (AD), Parkinson' s disease (PD) and multiple sclerosis (MS), respectively; enrichment analysis showed that MAPK, IL-17, PI3K-Akt and other signaling pathways were significantly expressed; the hub genes (HGs) of DEGs between ND and COVID-19 were CRH, SST, TAC1, SLC32A1, GAD2, GAD1, VIP and SYP. Analysis of transcriptome data suggests multiple co-morbid mechanisms between COVID-19 and AD, PD, and MS, providing new ideas and therapeutic strategies for clinical prevention and treatment of COVID-19 and ND.

The Interactions among Hypertension, Cancer, and COVID-19: Perspectives from Ca2+/cAMP Signalling

BACKGROUND

The hypothesis that hypertension is clinically associated with an enhanced risk for developing cancer has been highlighted. However, the working principles involved in this link are still under intensive discussion. A correlation among inflammation, hypertension, and cancer could accurately describe the clinical link between these diseases. In addition, a dyshomeostasis of Ca²⁺ has been considered as a topic involved in both cancer and hypertension and inflammation. There is a strong link between Ca²⁺ signalling, e.g. enhanced Ca²⁺ signals, and inflammatory outcomes. cAMP also modulates pro- and anti-inflammatory outcomes: pharmaceuticals, which increase intracellular cAMP levels, can decrease the production of proinflammatory mediators and enhance the production of anti-inflammatory outcomes.

OBJECTIVE

This article has discussed the participation of Ca²⁺/cAMP signalling in the clinical association among inflammation, hypertension, and an enhanced risk for the development of cancer. In addition, considering coronavirus disease 2019 (COVID-19) is a rapidly evolving field, this article also reviews recent reports about the role of Ca²⁺ channel blockers for restoring Ca²⁺ signalling disruption due to COVID-19, including the relationship among COVID-19, cancer, and hypertension.

CONCLUSION

Understanding the association among these diseases could expand current pharmacotherapy, including that involving Ca²⁺ channel blockers and pharmaceuticals which rise cAMP levels.

A Link Between Brain Insulin Resistance and Cognitive Dysfunctions: Targeting Ca2+/cAMP Signalling

BACKGROUND

A correlation between cognitive dysfunctions and brain insulin resistance has been established by several clinical and experimental studies. Consistent data support that people diagnosed with brain insulin resistance, resulted from diabetes, have shown an increased risk of presenting cognitive dysfunctions, clinical signs of dementia and depression, then speculating a role of dysregulations related to insulin signalling in these diseases. Furthermore, it is currently discussed that Ca2+ signalling, and its dysregulations, may be a factor which could correlate with brain insulin resistance and cognitive dysfunctions.

OBJECTIVE

Following this, revealing this interplay between these diseases may provide novel insights into the pathogenesis of such diseases.

METHODS

Publications covering topics such as Ca2+ signalling, diabetes, depression and dementia (alone or combined) were collected by searching PubMed and EMBASE.

RESULTS

The controlling of both neurotransmitters/hormones release and neuronal death could be achieved through modulating Ca2+ and cAMP signalling pathways (Ca2+/cAMP signalling).

CONCLUSION

Taking into account our previous reports on Ca2+/cAMP signalling, and considering a limited discussion in the literature on the role of Ca2+/cAMP signalling in the link between cognitive dysfunctions and brain insulin resistance, this article has comprehensively discussed the role of these signalling pathways in this link (between cognitive dysfunctions and brain insulin resistance).

Diabetes and inflammatory diseases: An overview from the perspective of Ca2+/3'-5'-cyclic adenosine monophosphate signaling

A large amount of evidence has supported a clinical link between diabetes and inflammatory diseases, e.g., cancer, dementia, and hypertension. In addition, it is also suggested that dysregulations related to Ca²⁺ signaling could link these diseases, in addition to 3'-5'-cyclic adenosine monophosphate (cAMP) signaling pathways. Thus, revealing this interplay between diabetes and inflammatory diseases may provide novel insights into the pathogenesis of these diseases. Publications involving signaling pathways related to Ca²⁺ and cAMP, inflammation, diabetes, dementia, cancer, and hypertension (alone or combined) were collected by searching PubMed and EMBASE. Both signaling pathways, Ca²⁺ and cAMP signaling, control the release of neurotransmitters and hormones, in addition to neurodegeneration, and tumor growth. Furthermore, there is a clear relationship between Ca²⁺ signaling, e.g., increased Ca²⁺ signals, and inflammatory responses. cAMP also regulates pro- and anti-inflammatory responses. Due to the experience of our group in this field, this article discusses the role of Ca²⁺ and cAMP signaling in the correlation between diabetes and inflammatory diseases, including its pharmacological implications. As a novelty, this article also includes: (1) A timeline of the major events in Ca²⁺/cAMP signaling; and (2) As coronavirus disease 2019 (COVID-19) is an emerging and rapidly evolving situation, this article also discusses recent reports on the role of Ca²⁺ channel blockers for preventing Ca²⁺ signaling disruption due to COVID-19, including the correlation between COVID-19 and diabetes.

A Hypothesis for the Relationship between Depression and Cancer: Role of Ca2+/cAMP Signalling

Limitations on the pharmacotherapy and a high prevalence worldwide are critical issues related to depression and cancer. It has been discussed that a dysregulation of intracellular Ca2+ homeostasis is involved in the pathogenesis of both these diseases. In addition, depression raises the risk of cancer incidence. Consistent data support the concept that depression is an independent risk issue for cancer. However, the cellular mechanisms involved in this link between depression and cancer remain uncertain. Considering our previous reports about Ca2+ and cAMP signalling pathways (Ca2+/cAMP signalling), I herein discussed the putative contribution of Ca2+/cAMP signalling in this link between depression and cancer. Moreover, it is important to take depression into account during the process of prevention and treatment of cancer.

The Interactions Between Alzheimer's Disease and Major Depression: Role of Ca2+ Channel Blockers and Ca2+/cAMP Signalling

BACKGROUND

The interactions between Alzheimer's Disease (AD) and major depression can be translated into clinical data showing that depressive patients have had an enhanced risk for developing AD (later in life). The cellular mechanisms involved in these interactions remain under intensive debate in the literature. In addition, the role of a Ca²⁺ homeostasis dysregulation in the pathogenesis of neurodegenerative diseases, like AD, and major depression has been under intensive discussion.

OBJECTIVE

Thus, revealing the interplay between AD and major depression may provide novel insights into the pathogenesis of these diseases.

METHODS

Publications involving Ca²⁺ signalling pathways, AD, and major depression (alone or combined) were collected by searching multiple databases to find the maximum number of relevant citations (using a search strategy with high sensitivity for studies of etiology).

RESULTS

Ca²⁺ Channel Blockers (CCBs), classically prescribed for hypertensive patients, have been demonstrating neuroprotective effects, such as decreasing the incidence of AD in hypertensive patients, including alleviating major depression symptoms. A mechanism under debate is focused on the restoration of the Ca²⁺ homeostasis. Indeed, previous studies of our own have correlated Ca²⁺ and cAMP signalling pathways (Ca²⁺/cAMP signalling) in controlling both the neurotransmitter release and neuronal death. These studies also observed that CCBs can affect Ca²⁺/cAMP signalling.

CONCLUSION

This review discussed the plausible role of Ca²⁺/cAMP signalling in the neuroprotective effects of CCBs, including the participation of Ca²⁺/cAMP signalling in the interactions between major depression and AD. Considering both AD and major depression have become highly prevalent medical problems in the world, the comprehension of the interactions between these diseases could improve drug development.

The Interplay Between Asthma and Other Diseases: Role of Ca2+/cAMP Signalling

OBJECTIVE

Asthma is correlated with a higher risk of manifesting other diseases, including hypertension, diabetes, obesity, psychiatric and neurological diseases, and cancer. Therefore, revealing this interplay between asthma and these illnesses may provide novel insights into their pathogenesis.

RESULTS

It is highly debated that dysregulation of Ca2+ homeostasis is involved in the pathogenesis of these maladies. Not surprisingly, calcium (Ca2+) channel blockers (CCBs), classically used as antihypertensive medicines, have been demonstrating off-label effects such as alleviating asthma symptoms, in addition to antidiabetic, antiobesity, anticancer and antineurodegenerative effects. Our studies about Ca2+/cAMP signalling may shed some new light on this field.

CONCLUSION

Thus, considering that asthma and associated illnesses such as hypertension, diabetes, obesity, cancer and neurodegenerative diseases have become highly prevalent medical problems in the world, the comprehension of this interplay between asthma and other disorders could improve drug therapy.

Depression Rises the Risk of Hypertension Incidence: Discussing the Link through the Ca2+/cAMP Signalling

BACKGROUND

Depression and hypertension are medical problems both with clearly restricted pharmacotherapies, along with a high prevalence around the world. In fact, an intensive discussion in the field is that a dysregulation of the intracellular Ca2+ homeostasis (e.g. excess of intracellular Ca2+) contributes to the pathogenesis of both hypertension and depression. Furthermore, depression rises the risk of hypertension incidence. Indeed, several data support the concept that depression is an independent risk issue for hypertension.

CONCLUSION

Then, which are the possible cellular mechanisms involved in this link between depression and hypertension? Considering our previous reports about the Ca2+ and cAMP signalling pathways (Ca2+/cAMP signalling), in this review I have discussed the virtual involvement of the Ca2+/cAMP signalling in this link (between depression and hypertension). Then, it is important to consider depression into account during the process of prevention, and treatment, of hypertension.

Common issues among asthma, epilepsy, and schizophrenia: from inflammation to Ca2+/cAMP signalling

BACKGROUND

A large amount of evidence has described that asthma may be associated with a high epilepsy risk, and epilepsy may be linked with a high asthma risk, especially among children and individuals in their 30s. Curiously, asthma has also been associated with an increased risk for schizophrenia. Most interestingly, a bidirectional link between schizophrenia and epilepsy has also been established, and has been of interest for many years.

OBJECTIVE

Bearing in mind the experience of our group in the field of Ca2+/cAMP signalling pathways, this article discussed, beyond inflammation, the role of these signalling pathways in this link among epilepsy, asthma, and schizophrenia.

METHODS

Publications involving these signalling pathways, asthma, epilepsy, and schizophrenia (alone or combined) were collected by searching PubMed and EMBASE.

RESULTS AND CONCLUSION

There is a clear relationship between Ca2+ signalling, e.g. increased Ca2+ signals, and inflammatory responses. In addition to Ca2+, cAMP regulates pro- and anti-inflammatory responses. Then, beyond inflammation, the comprehension of the link among epilepsy, asthma and schizophrenia could improve the drug therapy.

A link among schizophrenia, diabetes, and asthma: Role of Ca2+/cAMP signaling

Asthma has been associated with an increased risk for developing schizophrenia. In addition, schizophrenia has been associated with an increased risk for developing type 2 diabetes mellitus, resulting in an elevated cardiovascular risk and in a limited life expectancy. It is well discussed that dysregulations related to Ca²⁺ signaling could link these diseases, in addition to cAMP signaling pathways. Thus, revealing this interplay among schizophrenia, diabetes, and asthma may provide novel insights into the pathogenesis of these diseases. Publications involving Ca²⁺ and cAMP signaling pathways, schizophrenia, diabetes, and asthma (alone or combined) were collected by searching PubMed and EMBASE. Both Ca²⁺ and cAMP signaling pathways (Ca²⁺/cAMP signaling) control the release of neurotransmitters and hormones, in addition to airway smooth muscle contractility, then dysregulations of these cellular processes may be involved in these diseases. Taking into consideration, the experience of our group in this field, this narrative review debated the involvement of Ca²⁺/cAMP signaling in this link among schizophrenia, diabetes, and asthma, including its pharmacological implications.

The β-cell effect of verapamil-based treatment in patients with type 2 diabetes: a systematic review

AIMS

The possibility that verapamil has new beneficial effects in diabetic patients in terms of an improvement in glycometabolic control has been put forward recently in several studies. However, to date the issue is still under debate. We conducted the first systematic review examining the impact of verapamil-based treatment on glycometabolic outcomes, in type 2 diabetes (T2D) patients.

METHODS

We searched the PubMed, MEDLINE, Embase, Cochrane and ClinicalTrials.gov up to 9 October 2018, for all studies evaluating whether verapamil-based treatment is associated with changes in glycated haemoglobin (HbA1c), fasting plasma glucose levels, glucose and C-peptide areas from baseline in humans, without restrictions for study type.

RESULTS

Plasma glucose levels were lowered significantly by verapamil-based treatment in patients with T2D (mean change - 13 ± 5.29; P = 0.049); HbA1c values were instead not affected by the drug (mean change - 0.10 ± 0.12; P = 0.453). In five studies, groups exposed to verapamil achieved lower value of glycometabolic outcomes: comparison with values recorded in control groups showed a significant difference, in terms of both HbA1c and plasma glucose levels.

CONCLUSIONS

Despite the fact that plasma glucose levels were lowered significantly by verapamil-based treatment in patients with T2D (the HbA1c values were not affected by the drug), the clinical significance of the glycometabolic response induced by verapamil-based treatment remains unclear due to the high variety of sample size and type of studies presently available. Further experimental and clinical trials are needed to clarify unambiguously the role of verapamil in metabolic control.

Diabetes and Parkinson's Disease: Debating the Link Through Ca2+/cAMP Signalling

BACKGROUND

A link between diabetes and Parkinson´s disease (PD) has been established by several reports. Consistent data report that people diagnosed with diabetes have demonstrated an enhanced risk of manifesting PD in their lifetime. The working principles involved in this link have been extensively discussed. Over the last decade, diabetes has been reported to be correlated with an increased risk of dementia, suggesting a potential role of diabetes, or insulin signalling dysregulations, in neurodegeneration. In addition, it is nowadays highly debated that dysregulations related to Ca2+ signalling may be an upstream issue which could also link diabetes and PD. Ca2+ and cAMP signalling pathways (Ca2+/cAMP signalling) control both the neurotransmitters/hormones release and neuronal death.

CONCLUSION

Considering our previous reports about Ca2+/cAMP signalling, the putative contribution of Ca2+/cAMP signalling in this link (between diabetes and PD) is discussed in this paper.

Hypertension, Diabetes and Neurodegenerative Diseases: Is there a Clinical Link through the Ca2+/cAMP Signalling Interaction?

BACKGROUND

Hypertension, diabetes and neurodegenerative diseases are among the most prevalent medical problems around the world, costing millions of dollars to the medical health systems. Indeed, hypertension has been associated with higher risk for decline of cognition, as evidenced in patients with Alzheimer´s disease (AD). Furthermore, there is a clear relationship between hypertension and diabetes, reflecting substantial overlap in their etiology. Calcium (Ca2+) channel blockers (CCBs) have been classically prescribed for treating hypertension because of their mechanism of action due to reducing the influx of Ca2+ into the smooth muscles cells. In addition, many clinical and experimental studies have been demonstrating pleiotropic effects for CCBs. For instance, in hypertensive patients treated with CCBs, it can be observed lower incidence of neurodegenerative diseases such as AD. The virtual mechanism of action could be attributed to a restoration and maintenance of Ca2+ homeostasis, which is dysregulated in the neurodegenerative diseases, including also a reduction of neuronal apoptosis as part of these CCBs pleiotropic effects. Similarly, in hypertensive patients treated with CCBs, it can be observed an improvement of diabetes status such as glycemic control. A possible mechanism of action under debate could be attributed to a restoration of insulin secretion, then achieving glycemic control, and reduction of pancreatic β-cell apoptosis.

CONCLUSION

Considering the discovery of our group entitled "calcium paradox" due to Ca2+/cAMP signalling interaction, in this review I discussed the virtual involvement of this interaction in the pleiotropic effects of CCBs, including the possible role of the Ca2+/cAMP signalling interaction in the association between hypertension and higher risk for the decline of cognition, and diabetes.

Diabetes and cancer: Debating the link through Ca2+/cAMP signalling

The incidence of both cancer and diabetes is dramatically increasing in worldwide population, costing many millions from governments into expenditures related to medical health systems. Diabetes has been clinically linked to an increased risk for developing several types of cancer. The cellular mechanisms involved in this link are still under intensive debate in literature. In addition, a Ca²⁺ homeostasis dysregulation has been intensively debated as an issue involved in both cancer and diabetes. Calcium (Ca²⁺) channel blockers (CCBs), prescribed for treating hypertension, have also been showing anti-cancer effects along with reducing diabetes symptoms. A debated mechanism of action could rest in the fact that CCBs may restore Ca²⁺ homeostasis dysregulations, involved in both diseases. Our studies about Ca²⁺/cAMP signalling may add some new light in this field. In this review, I have debated the possible involvement of Ca²⁺/cAMP signalling in the clinical link between diabetes and a higher risk for the development of several types of cancer, including the plausible involvement in both anti-cancer and anti-diabetic effects of CCBs.

Debating the "bidirectional link" between diabetes and depression through the Ca2+/cAMP signalling: Off-label effects of Ca2+ channel blockers

Many reports have been demonstrating off-label effects for calcium (Ca²⁺) channel blockers (CCBs), for example: patients medicated with CCBs have had an improvement of their diabetes status (control of glycemia), along with an improvement of both depression symptoms and cognitive function. Indeed, diabetes and depression are medical problems both with clearly restricted pharmacotherapies, along with a high prevalence around the world, then costing millions and millions for the medical health systems. Furthermore, the incidence of depression is till three times higher in patients with diabetes. In addition, depression may augment the risk of developing type 2 diabetes till 60%. Then, there is a clear "bidirectional link" between depression and diabetes, reflecting substantial interactions in their etiology. But which are the possible cellular mechanisms for this "bidirectional link" between depression and diabetes, and for the off-label effects of CCBs? Considering our previously cited international articles, which demonstrated the role of the Ca²⁺/cAMP signalling in regulating both the neurotransmitter release and the neuronal death, in this review I have debated the possible involvement of the Ca²⁺/cAMP signalling in the off-label effects of CCBs, including the role of the Ca²⁺/cAMP signalling in the "bidirectional link" between diabetes and depression.

Revealing Clusters of Connected Pathways Through Multisource Data Integration in Huntington's Disease and Spastic Ataxia

The advancement of scientific and medical research over the past years has generated a wealth of experimental data from multiple technologies, including genomics, transcriptomics, proteomics, and other forms of -omics data, which are available for a number of diseases. The integration of such multisource data is a key component toward the success of precision medicine. In this paper, we are investigating a multisource data integration method developed by our group, regarding its ability to drive to clusters of connected pathways under two different approaches: first, a disease-centric approach, where we integrate data around a disease, and second, a gene-centric approach, where we integrate data around a gene. We have used as a paradigm for the first approach Huntington's disease (HD), a disease with a plethora of available data, whereas for the second approach the GBA2, a gene that is related to spastic ataxia (SA), a phenotype with sparse availability of data. Our paper shows that valuable information at the level of disease-related pathway clusters can be obtained for both HD and SA. New pathways that classical pathway analysis methods were unable to reveal, emerged as necessary "connectors" to build connected pathway stories formed as pathway clusters. The capability to integrate multisource molecular data, concluding to something more than the sum of the existing information, empowers precision and personalized medicine approaches.

Treatments for diabetes mellitus type II: New perspectives regarding the possible role of calcium and cAMP interaction

Diabetes mellitus (DM) is among the top ten causes of death worldwide. It is considered to be one of the major global epidemics of the 21st century, with a significant impact on public health budgets. DM is a metabolic disorder with multiple etiologies. Its pathophysiology is marked by dysfunction of pancreatic β-cells which compromises the synthesis and secretion of insulin along with resistance to insulin action in peripheral tissues (muscle and adipose). Subjects presenting insulin resistance in DM type 2 often also exhibit increased insulin secretion and hyperinsulinemia. Insulin secretion is controlled by several factors such as nutrients, hormones, and neural factors. Exocytosis of insulin granules has, as its main stimulus, increased intracellular calcium ([Ca⁺²]i) and it is further amplified by cyclic AMP (cAMP). In the event of this hyperfunction, it is very common for β-cells to go into exhaustion leading to failure or death. Several animal studies have demonstrated pleiotropic effects of L-type Ca²⁺ channel blockers (CCBs). In animal models of obesity and diabetes, treatment with CCBs promoted restoration of insulin secretion, glycemic control, and reduction of pancreatic β-cell apoptosis. In addition, hypertensive individuals treated with CCBs presented a lower incidence of DM when compared with other antihypertensive agents. In this review, we propose that pharmacological manipulation of the Ca²⁺/cAMP interaction system could lead to important targets for pharmacological improvement of insulin secretion in DM type 2.

Challenges for the pharmacological treatment of neurological and psychiatric disorders: Implications of the Ca(2+)/cAMP intracellular signalling interaction

In 2013, we discovered that the entitled "calcium paradox" phenomenon, which means a paradoxical sympathetic hyperactivity produced by l-type Ca(2+) channel blockers (CCBs), used in antihypertensive therapy, is due to interaction between the intracellular signalling pathways mediated by Ca(2+) and cAMP (Ca(2+)/cAMP interaction). In 2015, we proposed that the pharmacological manipulation of this interaction could be a new therapeutic strategy for increasing neurotransmission in psychiatric disorders, and producing neuroprotection in the neurodegenerative diseases. Besides the paradoxical sympathetic hyperactivity produced by CCBs, several clinical studies have been demonstrating pleiotropic effects of CCBs, including neuroprotective effects. CCBs genuinely exhibit cognitive-enhancing abilities and reduce the risk of dementia, including Alzheimer's, Parkinson´s disease and others. The molecular mechanisms involved in these pleiotropic effects remain under debate. Our recent discovery that the "calcium paradox" phenomenon is due to Ca(2+)/cAMP interaction may provide new insights for the pharmacological treatment of neurological and psychiatric disorders, including enhancement of current therapies mainly by reducing adverse effects, and improving effectiveness of modern medicines. Whether Ca(2+)/cAMP interaction is involved in CCBs pleiotropic effects also deserves special attention. Then, the pharmacological manipulation of the Ca(2+)/cAMP interaction could be a more efficient therapeutic strategy for increasing neurotransmission in psychiatric disorders, and producing neuroprotection in the neurodegenerative diseases. Thus, in this review we summarize the current knowledge of this field, making new directions and future perspectives.