ULK1 confers neuroprotection by regulating microglial/macrophages activation after ischemic stroke

Novel insight into the role of Src family kinases in hepatocellular carcinoma and therapeutic potential

Hepatocellular carcinoma remains a highly aggressive malignancy, with the 5-year survival rate for advanced-stage patients persisting below 20 % despite progress in targeted therapies and immunotherapy. This clinical reality underscores the critical need for identifying novel therapeutic targets. Src family kinases (SFKs), critical regulators of cellular metabolism, coordinate regenerative repair through STAT3/ERK signaling in normal hepatic regeneration and preserve cellular polarity via FAK-mediated mechanisms following hepatic injury. Growing evidence suggests that dysregulation of SFKs expression and activity is closely associated with oxidative stress, inflammation-cancer transition, metabolic reprogramming disorders and microenvironmental remodeling in hepatocellular carcinoma. However, the underlying mechanisms remain inadequately understood. This review provides a comprehensive overview of the composition and structure of SFKs. We explored in depth the molecular and cellular mechanisms of SFKs in the pathological progression and risk factors of hepatocellular carcinoma, including viral hepatitis, metabolic dysfunction-associated steatohepatitis, and other established risk factors. Herein, we highlight the potential of SFKs as a pharmacological target against hepatocellular in the hope of inspiring translational research and innovative clinical approaches.

MAM-mediated mitophagy and endoplasmic reticulum stress: the hidden regulators of ischemic stroke

Ischemic stroke (IS) is the predominant subtype of stroke and a leading contributor to global mortality. The mitochondrial-associated endoplasmic reticulum membrane (MAM) is a specialized region that facilitates communication between the endoplasmic reticulum and mitochondria, and has been extensively investigated in the context of neurodegenerative diseases. Nevertheless, its precise involvement in IS remains elusive. This literature review elucidates the intricate involvement of MAM in mitophagy and endoplasmic reticulum stress during IS. PINK1, FUNDC1, Beclin1, and Mfn2 are highly concentrated in the MAM and play a crucial role in regulating mitochondrial autophagy. GRP78, IRE1, PERK, and Sig-1R participate in the unfolded protein response (UPR) within the MAM, regulating endoplasmic reticulum stress during IS. Hence, the diverse molecules on MAM operate independently and interact with each other, collectively contributing to the pathogenesis of IS as the covert orchestrator.

BL-918 alleviates oxidative stress in rats after subarachnoid hemorrhage by promoting mitophagy through the ULK1/PINK1/Parkin pathway

BACKGROUND AND PURPOSE

Oxidative stress plays a critical role in early brain injury (EBI) following subarachnoid hemorrhage (SAH). The small molecule ULK1 agonist, BL-918, demonstrated neuroprotective effects in other central nervous system diseases; however, its role in SAH has not yet been explored. This study aimed to evaluate whether BL-918 could provide neuroprotective effects in rats following SAH.

METHODS

An SAH model was established in Sprague-Dawley rats using endovascular perforation. BL-918 was administered intraperitoneally after SAH, while the ULK1 inhibitor SBI was given intraperitoneally prior to SAH modeling. PINK1 siRNA was administered into the lateral ventricle before SAH induction. The neuroprotective effects and mechanisms of BL-918 were assessed through SAH grading, brain water content measurement, blood-brain barrier permeability, neurobehavioral tests, Western blot, immunofluorescence, TUNEL staining, DHE staining, and transmission electron microscopy (TEM).

RESULTS

After SAH, the expression levels of p-ULK1, PINK1, Parkin, and LC3Ⅱ increased, peaking at 24 h post-SAH. BL-918 treatment improved neurological function in rats, reduced brain water content and blood-brain barrier permeability, and exhibited anti-oxidative stress and anti-apoptotic effects. Western blot analysis revealed that BL-918 increased the expression of p-ULK1, PINK1, Parkin, LC3Ⅱ, Bcl-xl, and Bcl-2 while inhibiting the expression of Bax and Cleaved Caspase-3. Oxidative stress-related indicators showed that BL-918 alleviated oxidative stress. Immunofluorescence and TEM results demonstrated that BL-918 promoted mitophagy and preserved mitochondrial morphology. Furthermore, the positive effects of BL-918 were reversed by SBI and PINK1 siRNA, respectively.

CONCLUSION

BL-918 improved both short-term and long-term neurological impairments in rats after SAH and reduced oxidative stress by promoting mitophagy, at least partially through the ULK1/PINK1/Parkin signaling pathway.