Thermosensitive Hydrogel Derived from a Human Amniotic Membrane Promotes Diabetic Wound Healing

Extracellular matrix (ECM) hydrogels are recognized as
promising
biomaterials for regenerative medicine owing to their ability to recapitulate
the native tissue microenvironment. The human amniotic membrane (AM),
readily available and posing little to no ethical concerns, is rich
in ECM components with inherent wound-healing potential. This study
aimed to develop and characterize thermosensitive hydrogels derived
from a decellularized AM and assess their therapeutic potential for
diabetic wound healing. The native AM was subjected to detergent-enzymatic
decellularization to remove the cellular content while preserving
the essential ECM. The resulting acellular AM was lyophilized, cryomilled,
and digested with pepsin under acidic conditions at three different
concentrations. The pregel solutions were neutralized and thermally
induced to form AM ECM hydrogels at 37 °C. The physicochemical
properties, including gelation kinetics, swelling, porosity, mechanical
stiffness, and biodegradation, were evaluated. The biological evaluation
was assessed using fibroblasts, keratinocytes, and endothelial cells
through live/dead staining, the MTS assay, and analyses of ROS production,
apoptosis, cytoskeletal organization, and cell migration. Proteomic
profiling was conducted to identify the retained matrisome proteins.
The in vivo performance was tested in a diabetic murine full-thickness
wound model. AM ECM hydrogels exhibited temperature-dependent gelation
(t1/2: ∼12.75–27 min), high
water content (>97%), and >60% porosity. All formulations supported
>70% cell viability at 24 h and >300% proliferation at 72 h,
with
negligible ROS production, minimal apoptosis, and preserved cytoskeletal
integrity. The proteomic analysis confirmed the maintenance of matrisome
proteins related to epithelial differentiation, angiogenesis, and
tissue repair. The in vivo study demonstrated that the AM ECM hydrogel
accelerated wound healing, evidenced by early wound closure, along
with vascular stabilization, regulated inflammatory response, and
ECM stabilization compared to those of the control group. These findings
collectively demonstrate that AM ECM hydrogel treatment in diabetic
mice ameliorates wound pathology, as evidenced by reduced severity,
a modulated inflammatory response, and decreased fibrotic burden.