Coordination Compounds As Multi-Delivery Systems for Osteoporosis

Osteoporosis
therapies leveraging bisphosphonates and mineral components
(e.g., magnesium, calcium, and strontium) have been raising attention
because of their potential for managing this ever-growing disease.
The administration of multicomponent therapeutics (combined therapy)
in elderly patients is complex and suffers from low patient adherence.
Herein, we report an all-in-one combination of four antiosteoporotic
components into a new family of coordination complexes: [M2(H4alen)4(H2O)2]·1.5H2O [where M2+ = Mg2+ (1),
(Mg0.535Ca0.465)2+ (2) and (Mg0.505Ca0.450Sr0.045)2+ (3)]. These solid-state complexes were prepared,
for the first time, through microwave-assisted synthesis. It is demonstrated
that the compounds are capable of releasing their antiosteoporotic
components, both in conditions that mimic the path along the gastrointestinal
tract and in long periods under physiological conditions (pH ∼7.4).
More importantly, when administered in low concentrations, the compounds
did not elicit a cytotoxic effect toward liver, kidney, and osteoblast-like
cell lines. Besides, it is important to highlight the unique coordination
complex with four bone therapeutic components, [(Mg0.505Ca0.450Sr0.045)2(H4alen)4(H2O)2]·1.5H2O (3), which significantly promoted osteoblast metabolic activity
up to ca. 1.4-fold versus the control group. These findings bring
this type of compounds one-step closer to be considered as an all-in-one
and more effective treatment for managing chronic bone diseases, prompting
further research on their therapeutic properties.