Metformin Ameliorates Early Brain Injury After Subarachnoid Hemorrhage Via Improving Endoplasmic Reticulum Stress and Mitochondrial Stress-Mediated Ca2+ Imbalance
Year: 2025
Type: article
Abstract: Subarachnoid hemorrhage (SAH) is a destructive subtype of stroke characterized by a high mortality and morbidity rate (45–50%) and a poor neurologic prognosis, encompassing both neurological and psychiatric impairments. It will be more imperative to explore new therapeutic strategies for early brain injury (EBI) to enhance the prognosis of patients with SAH. First, we investigated the role of endoplasmic reticulum stress (ERS) and mitochondrial stress (MS) in mediating the IP3R1–GRP75–VDAC1 Ca 2 ⁺ channeling complex within the first 72 h following SAH in mice. Neurological function was assessed prior to euthanasia, and brain water content was measured post-sacrifice in each group. The ultrastructural composition of mitochondria-associated membrane (MAM) was examined using transmission electron microscopy (TEM). Protein expressions related to ERS, MS, and apoptosis were evaluated by immunofluorescence and Western blot. Metformin (Met) administration improved neurological scores and reduced brain edema at 24 h post-SAH, likely through ameliorating ERS- and MS-mediated Ca 2 ⁺ dysregulation. Finally, the beneficial effect of Met was further confirmed in an in vitro SAH model, yielding consistent results. Stimulation of arterial blood aggravates the ERS and MS through the PTP1B/AKT axis, further affecting the structure and function of the MAM following SAH. The MAM formation mediates the IP3R1–GRP75–VDAC1 complex, playing an important role in Ca 2+ transport. The Met treatment could ameliorate ER stress, MS, and Ca 2+ overload, further alleviating the EBI of SAH.
Source: Molecular Neurobiology
Authors: Zhonghua Zhang, Jingbei Zhang, Liping Li, Lin Zong
Language: English
Subfield: Neurology
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $4,590
Award: G2690573773
OpenAlex ID: W4417030403
