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Is Cardiac Diastolic Dysfunction a Part of Post-Menopausal Syndrome?
Maslov, PZ, Kim, JK, Argulian, E, Ahmadi, A, Narula, N, Singh, M, Bax, J, Narula, J
JACC. Heart failure. 2019;(3):192-203
Abstract
Post-menopausal women exhibit an exponential increase in the incidence of heart failure with preserved ejection fraction compared with men of the same age, which indicates a potential role of hormonal changes in subclinical and clinical diastolic dysfunction. This paper reviews the preclinical evidence that demonstrates the involvement of estrogen in many regulatory molecular pathways of cardiac diastolic function and the clinical data that investigates the effect of estrogen on diastolic function in post-menopausal women. Published reports show that estrogen deficiency influences both early diastolic relaxation via calcium homeostasis and the late diastolic compliance associated with cardiac hypertrophy and fibrosis. Because of the high risk of diastolic dysfunction and heart failure with preserved ejection fraction in post-menopausal women and the positive effects of estrogen on preserving cardiac function, further clinical studies are needed to clarify the role of endogenous estrogen or hormone replacement in mitigating the onset and progression of heart failure with preserved ejection fraction in women.
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2.
Molecular basis of vitamin D action in neurodegeneration: the story of a team perspective.
Gezen-Ak, D, Dursun, E
Hormones (Athens, Greece). 2019;(1):17-21
Abstract
Vitamin D, a secosteroid hormone, has, over the years, mainly been known for its classic role in the maintenance of calcium homeostasis of the human body. However, there is increasing understanding that vitamin D contributes to the regulation of Ca2+ homeostasis, especially via voltage-gated calcium channels, in another major organ that uses calcium, the brain. Almost 30 years ago, the role of dysregulation in the aging brain and in Alzheimer's disease (AD) gave rise to the Ca2+ hypothesis of brain aging and dementia. We thus made calcium homeostasis the starting point of our studies, proposing the notion that the consequences of long-term deficiency and/or inefficient utilization of vitamin D may cause the disruption of calcium homeostasis in neurons, this creating a vulnerability of neurons to aging and neurodegeneration. In this mini-review, we aim to describe the potential of vitamin D (cholecalciferol) as a neurosteroid based on our findings and conclusions.
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3.
Vitamin D in burn-injured patients.
Rech, MA, Colon Hidalgo, D, Larson, J, Zavala, S, Mosier, M
Burns : journal of the International Society for Burn Injuries. 2019;(1):32-41
Abstract
Recently, many studies have demonstrated pleotropic effects of vitamin D, including immune modulation and cardiovascular system activity. Sufficient vitamin D concentrations and supplementation of vitamin D may be of benefit in burn-injured patients. Low 25(OH)D has been observed in nearly all pediatric and most adult burn patients. Vitamin D has primarily been studied in pediatric burn patients, focusing on bone marker measurements and the incidence of fractures. The preferred vitamin D dose, formulation, and route of administration remain unknown, and there is limited data on the impact of vitamin D status on clinical outcomes. Further research should focus on determining optimal monitoring strategies, supplementation regimens and clinical outcomes like mortality, length of stay and incidence of sepsis.
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4.
Sarcoidosis and calcium homeostasis disturbances-Do we know where we stand?
Gwadera, Ł, Białas, AJ, Iwański, MA, Górski, P, Piotrowski, WJ
Chronic respiratory disease. 2019;:1479973119878713
Abstract
The majority of cases involving hypercalcemia in the setting of sarcoidosis are explained by the overproduction of calcitriol by activated macrophages. Vitamin D takes part in the regulation of granuloma formation. However, using vitamin D metabolites to assess the activity of the disease is still problematic, and its usefulness is disputable. In some cases, though, a calcium metabolism disorder could be a valuable tool (i.e. as a marker of extrathoracic sarcoidosis). Although sarcoidosis does not cause a decrease in bone mineral density, increased incidence of vertebral deformities is noted. Despite increasing knowledge about calcium homeostasis disorders in patients with sarcoidosis, there is still a need for clear guidelines regarding calcium and vitamin D supplementation in these patients.
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5.
[Role of Ca2+ in hypoxic pulmonary vasoconstriction].
Wei, G, Cheng, Y, Huang, Y, He, Q
Zhonghua wei zhong bing ji jiu yi xue. 2019;(5):647-649
Abstract
In acute hypoxia, pulmonary vascular will contract and divert blood to better ventilated area to optimize ventilation/perfusion matching, which is known as hypoxic pulmonary vasoconstriction (HPV). In chronic hypoxia, irreversible pulmonary vascular remodeling can be induced, characterized by pulmonary artery middle smooth muscle cells and the outer fiber cell hyperplasia in luminal stenosis and pulmonary artery hypertension (PAH) eventually. Furthermore, PAH can cause increased ventricular afterload, and right heart failure in severe cases. Pulmonary artery smooth muscle cell (PASMC) elevated Ca2+ concentration is one of the most important factors of its contractions, proliferation and migration. Recent studies on Ca2+ promoting in HPV were summarized in order to provide evidence for clinical prevention of hypoxia and therapeutic PAH.
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6.
Calcium-mediation of jasmonate biosynthesis and signaling in plants.
Wang, X, Zhu, B, Jiang, Z, Wang, S
Plant science : an international journal of experimental plant biology. 2019;:110192
Abstract
Jasmonates (JAs) play vital roles in regulating a range of plant growth and development processes including seed germination, seedling development, reproduction, formation and development of storage organs, and senescence. JAs are also involved in the regulation of plant responses to environmental stimuli. The biosynthesis of JAs takes place in three different subcellular compartments, namely, the chloroplast, peroxisome, and cytoplasm. JAs activate the expression of JA-responsive genes by degrading jasmonate zinc-finger-inflorescence meristem (Zim) domain (JAZ) repressors via the E3 ubiquitin-ligase Skp/Cullin/F-box protein CORONATINE INSENSITIVE1 (COI1) complex (SCFCOI1) by using 26S proteasome. Calcium, reactive oxygen species (ROS), mitogen-activated protein kinase (MAPK), and nitric oxide (NO) are involved in the regulation of the biosynthesis and signaling of JAs in plants. Among these signaling molecules, calcium is one of the most important within plant cells. In plants, intracellular calcium levels change in response to JAs, resulting in calcium signatures with temporal and spatial features. Calcium channels are involved in the generation of calcium signatures. Calcium sensors, including calmodulins (CaMs), CaM-like proteins (CMLs), calcineurin B-like proteins (CBLs), and calcium-dependent protein kinases (CDPKs), can act to regulate the biosynthesis and signaling of JAs.
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7.
Magnesium and calcium ions: roles in bacterial cell attachment and biofilm structure maturation.
Wang, T, Flint, S, Palmer, J
Biofouling. 2019;(9):959-974
Abstract
The ubiquitous divalent cations magnesium and calcium are important nutrients required by bacteria for growth and cell maintenance. Multi-faceted roles are shown both in bacterial initial attachment and biofilm maturation. The effects of calcium and magnesium can be highlighted in physio-chemical interactions, gene regulation and bio-macromolecular structural modification, which lead to either promotion or inhibition of biofilms. This review outlines recent research addressing phenotypic changes and mechanisms undertaken by calcium and magnesium in affecting bacterial biofilm formation.
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8.
Crosstalk between Calcium and ROS in Pathophysiological Conditions.
Feno, S, Butera, G, Vecellio Reane, D, Rizzuto, R, Raffaello, A
Oxidative medicine and cellular longevity. 2019;:9324018
Abstract
Calcium ions are highly versatile intracellular signals that regulate many cellular processes. The key to achieving this pleiotropic role is the spatiotemporal control of calcium concentration evoked by an extensive molecular repertoire of signalling components. Among these, reactive oxygen species (ROS) signalling, together with calcium signalling, plays a crucial role in controlling several physiopathological events. Although initially considered detrimental by-products of aerobic metabolism, it is now widely accepted that ROS, in subtoxic levels, act as signalling molecules. However, dysfunctions in the mechanisms controlling the physiological ROS concentration affect cellular homeostasis, leading to the pathogenesis of various disorders.
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9.
The Significance of Calcium in Photosynthesis.
Wang, Q, Yang, S, Wan, S, Li, X
International journal of molecular sciences. 2019;(6)
Abstract
As a secondary messenger, calcium participates in various physiological and biochemical reactions in plants. Photosynthesis is the most extensive biosynthesis process on Earth. To date, researchers have found that some chloroplast proteins have Ca2+-binding sites, and the structure and function of some of these proteins have been discussed in detail. Although the roles of Ca2+ signal transduction related to photosynthesis have been discussed, the relationship between calcium and photosynthesis is seldom systematically summarized. In this review, we provide an overview of current knowledge of calcium's role in photosynthesis.
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10.
SR-mitochondria communication in adult cardiomyocytes: A close relationship where the Ca2+ has a lot to say.
De la Fuente, S, Sheu, SS
Archives of biochemistry and biophysics. 2019;:259-268
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Abstract
In adult cardiomyocytes, T-tubules, junctional sarcoplasmic reticulum (jSR), and mitochondria juxtapose each other and form a unique and highly repetitive functional structure along the cell. The close apposition between jSR and mitochondria creates high Ca2+ microdomains at the contact sites, increasing the efficiency of the excitation-contraction-bioenergetics coupling, where the Ca2+ transfer from SR to mitochondria plays a critical role. The SR-mitochondria contacts are established through protein tethers, with mitofusin 2 the most studied SR-mitochondrial "bridge", albeit controversial. Mitochondrial Ca2+ uptake is further optimized with the mitochondrial Ca2+ uniporter preferentially localized in the jSR-mitochondria contact sites and the mitochondrial Na+/Ca2+ exchanger localized away from these sites. Despite all these unique features facilitating the privileged transport of Ca2+ from SR to mitochondria in adult cardiomyocytes, the question remains whether mitochondrial Ca2+ concentrations oscillate in synchronicity with cytosolic Ca2+ transients during heartbeats. Proper Ca2+ transfer controls not only the process of mitochondrial bioenergetics, but also of mitochondria-mediated cell death, autophagy/mitophagy, mitochondrial fusion/fission dynamics, reactive oxygen species generation, and redox signaling, among others. Our review focuses specifically on Ca2+ signaling between SR and mitochondria in adult cardiomyocytes. We discuss the physiological and pathological implications of this SR-mitochondrial Ca2+ signaling, research gaps, and future trends.