calcium

Overview

Calcium (Ca; atomic number 20) is the most abundant mineral in the human body and a divalent cation (Ca²⁺) essential to a wide range of physiological processes. Beyond its structural role as the primary mineral constituent of bones and teeth—where it exists predominantly as hydroxyapatite—calcium functions as a ubiquitous intracellular second messenger regulating cell signaling, muscle contraction, neurotransmitter release, enzyme activation, and apoptotic pathways. Intracellular Ca²⁺ concentrations are tightly maintained at nanomolar levels in the cytoplasm, while organelles such as the endoplasmic reticulum (ER), mitochondria, and lysosomes serve as dynamic Ca²⁺ reservoirs whose coordinated release and uptake govern excitability, metabolic coupling, and cell death decisions. Dysregulation of calcium homeostasis is implicated in a broad spectrum of pathologies, including neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, acute pancreatitis, eryptosis, and neoplastic transformation, making Ca²⁺ signaling axes a prominent target in pharmacological and biomaterial research.

In pharmaceutical and materials science contexts, the Ca²⁺ ion is exploited for its ability to ionically crosslink anionic polymers—most notably sodium alginate—forming stable hydrogel and capsule networks used in drug delivery, wound management, and food science. The versatility of calcium across biological signaling, clinical diagnostics, nutritional supplementation, and advanced biomaterial engineering has positioned it as one of the most actively investigated chemical entities in contemporary biomedical research.

Recent Publications Summary

Recent publications on calcium span mechanistic biology, clinical association studies, and materials/therapeutic applications. In bone and mineral metabolism, a review of gut-bone metabolites highlighted calcium-dependent signaling in the suppression of osteoclastogenesis, noting that microbial polyamines inhibit the Ca2+-PYK2-Src-NFATc1 axis as part of their pro-osteogenic effects 42495772Jul. A nationwide survey and genetic analysis also examined serum calcium alongside alkaline phosphatase and phosphorus across stages of cardiovascular-kidney-metabolic syndrome, reflecting interest in calcium as a marker of disordered mineralization 42313881Jun. In a longitudinal study of ageing women, pharmacological calcium supplementation was evaluated for its association with cognitive decline over 7 years, although the abstract does not report the final outcome 42159347May.

Several studies used calcium as a functional component in biomaterials and nanomedicine. In dental enamel research, calcium and vitamin D supplementation were tested for their ability to mitigate fluoride- and amoxicillin-associated enamel alterations in a rat incisor model; fluoride exposure, especially with amoxicillin, disrupted enamel prism organization and increased ameloblast apoptosis, while the study assessed whether supplementation could counter these effects 42184017May. A smart resin composite was also developed to provide acid-activated antibacterial activity together with controlled release of calcium and phosphate ions for prevention of secondary caries 41856393Mar. In food and polymer systems, Ca2+ was shown to synergize with transglutaminase to improve the gel strength, hardness, water-holding capacity, and network uniformity of potato protein-sesbania gum composite gels 41967536Apr, and Ca2+ helped construct more compact soy protein-sodium alginate hydrogels with improved tensile strain and structural stability 41895961Mar. Calcium-driven whey protein isolate fibrils were further used to stabilize high internal phase Pickering emulsions, with Ca2+-assisted fibrils producing a semi-flexible intertwined microstructure that enhanced emulsion stability at high frequencies 41762572Feb.

In cancer-focused nanotherapy, calcium was repeatedly leveraged as a trigger for intracellular stress. A TME-activated nanoreactor released Ca2+ while blocking lactate efflux, coupling lactate trapping with Ca2+-mediated oxidative stress to induce mitochondrial dysfunction and immunogenic cell death 42268380Jun. Another nanomotor based on calcium peroxide released Ca2+, hydrogen peroxide, copper(2+), and hesperidin in acidic tumor microenvironments, promoting reactive oxygen species generation, cuproptosis, and intracellular calcium accumulation 42126988May. A drug-free mitochondria-accumulative nanoplatform used calcium peroxide as a dual-functional initiator to release H2O2 and Ca2+, thereby combining chemodynamic therapy, calcium overload, and photothermal therapy to intensify mitochondrial dysfunction and apoptosis 41819039Mar. Calcium also appeared in the study of Waixenicin A derivatives, where the parent compound blocks TRPM7 and prevents calcium influx, and simplified derivatives retained partial TRPM7 inhibitory activity 42276815Jun. In ion-channel drug discovery, calcium channels were included among the channel classes targeted by a protein language model for predicting ion channel modulators 42321971Jun.

What Changes, What Holds

1. Calcium now appears as a signaling node in gut-bone and metabolic disease work, but the baseline role stands
REINFORCES Calcium-dependent suppression of osteoclastogenesis fits the established view of Ca²⁺ as a regulator of cell signaling and bone biology, while the serum-calcium association work mainly extends its clinical use as a biomarker in mineral metabolism. The ageing-women supplementation study is still unsettled in the summary, so it does not yet change the account of calcium’s effects on cognition. 42495772Jul42313881Jun42159347May

2. Calcium is being used more explicitly as a therapeutic material component, not a replacement for its established biomaterial role
REINFORCES These studies sharpen the existing account of Ca²⁺ as a crosslinker and structural modifier in hydrogels, gels, and composites, now extending that function into enamel protection, ion-releasing restorative materials, and food-protein networks. The new work does not overturn the baseline; it broadens the range of formulations in which calcium’s ionic chemistry is being exploited. 42184017May41856393Mar41967536Apr41895961Mar41762572Feb

3. Calcium overload is being pushed as an active anticancer mechanism, adding a therapeutic direction to its signaling biology
NEW DIRECTION The nanotherapy studies do not contradict the Overview’s description of calcium as a second messenger; they show that deliberate intracellular Ca²⁺ accumulation can be harnessed to drive mitochondrial dysfunction, oxidative stress, and cell death in tumors. That is a new use case rather than a replacement of the baseline, and it remains preclinical. The TRPM7 and ion-channel-model papers mainly reinforce calcium’s channel biology. 42268380Jun42126988May41819039Mar42276815Jun42321971Jun

Overview update candidates: calcium as a biomaterial crosslinker in newer composite/hydrogel systems; calcium overload as a deliberate anticancer strategy in preclinical nanotherapy.