Biomechanical homeostasis in ocular diseases: A mini-review

Abstract

Diabetes mellitus-induced hyperglycemia is responsible for multiple pathological ocular alternations from vasculopathy to biomechanical dyshomeostasis. Biomechanical homeostasis is crucial to maintain the normal physiological condition of the eyes. Biomechanical features vary in eye tissues regarding different anatomical positions, tissue components, and cellular functions. The disturbance in biomechanical homeostasis may result in different ocular diseases. In this review, we provide a preliminary sketch of the latest evidence on the mechano-environment of the eyeball and its possible influencing factors, thereby underscoring the relationship between the dyshomeostasis of ocular biomechanics and common eye diseases (e.g., diabetic retinopathy, keratoconus, glaucoma, spaceflight-associated neuro-ocular syndrome, retinal vein occlusion and myopia, etc.). Together with the reported evidence, we further discuss and postulate the potential role of biomechanical homeostasis in ophthalmic pathology. Some latest strategies to investigate the biomechanical properties in ocular diseases help unveil the pathological changes at multiple scales, offering references for making new diagnostic and treatment strategies targeting mechanobiology.

“Dual‐pressure theory” in pathogenesis of glaucomatous optic neuropathy from the Beijing intracranial and intraocular pressure study

“…These results showed that Piezo1 is an essential regulator in cell cycle progression in ONH astrocytes [54]. Other studies verified that chemical inhibition or genetic ablation of these mechanosensitive channels significantly ameliorates pathological phenotypes of optic nerve degeneration caused by IOP elevation, indicating the potential therapeutic roles of targeting mechanosensitive channels in glaucoma [52, 54, 55].…”

“…To update, this measuring method has been applied for early monitoring of spaceflight-associated neuroocular syndrome (SANS). SANS is featured as fluid redistribution in the optic nerve sheath and the cerebrospinal fluid cavity due to longterm exposure to the unique microgravity environment during extended spaceflight [55,63]. This novel and noninvasive method could help rapidly obtain a relatively accurate ICP through a mathematical formula based on ultrasonography; its future application in the detection and assessment of NTG is promising.…”

“…The "Dual-Pressure Theory" has been widely accepted, not only for consideration in glaucoma but also for approaches to multiple ophthalmic and neurological diseases including idiopathic intracranial hypertension [64], SANS [55], and high-altitude retinopathy [65].…”

“…The “Dual‐Pressure Theory” has been widely accepted, not only for consideration in glaucoma but also for approaches to multiple ophthalmic and neurological diseases including idiopathic intracranial hypertension [64], SANS [55], and high‐altitude retinopathy [65]. However, no standard reference value of TLCPD has been set up; the direct subtraction of IOP and ICP values from different studies may bring statistical bias caused by complicated influencing factors such as measurement approaches, inclusion criteria of subjects, races, measuring position, and so on.…”

Causal Association between Glaucoma and Risk of Retinal Vascular Occlusion: A Mendelian Randomization Study

“…Mohammadi M et al explored the mechanisms involved from a cell biological perspective: Cell proliferation in the lumen of the vein at the level of the lamina cribrosa and displacement of the vessel in the anterior portion of the optic nerve have been suggested to be causes of central/hemicentral RVOs 30 . In recent years, as the study of biomechanics in ocular diseases has been gradually deepened, the biomechanical mechanisms associated with RVO have been gradually revealed 31 . The physical obstruction of the retinal venous system is generally induced by thrombosis, deformation of the vein wall, and external biomechanical compression secondary to glaucoma 32 .…”