Isolation and characterization of components responsible for neuroprotective effects of
            Allium cepa
            outer scale extract against ischemia reperfusion induced cerebral injury in mice

Berberine exerts neuroprotective and modulates hypoxia inducible factor-1-alpha (HIF-1[Formula: see text]. Based on the role of HIF-1[Formula: see text] in hypoxia preconditioning and association between HIF-1[Formula: see text] and sphingosine-1-phosphate (S1P), we hypothesized that berberine preconditioning (BP) would ameliorate the cerebral injury induced by ischemia through activating the system of HIF-1[Formula: see text] and S1P. Adult male rats with middle cerebral artery occlusion (MCAO) and rat primary cortical neurons treated with oxygen and glucose deprivation (OGD) with BP at 24[Formula: see text]h (40[Formula: see text]mg/kg) and 2[Formula: see text]h (10[Formula: see text][Formula: see text]mol/L), respectively, were used to determine the neuroprotective effects. The HIF-1[Formula: see text] accumulation, and S1P metabolism were assayed in the berberine-preconditioned neurons, and the HIF-1[Formula: see text]-mediated transcriptional modulation of sphingosine kinases (Sphk) 1 and 2 was analyzed using chromatin immunoprecipitation and real-time polymerase chain reaction. BP significantly prevented cerebral ischemic injury in the MCAO rats at 24[Formula: see text]h and 72[Formula: see text]h following ischemia/reperfusion. In OGD-treated neurons, BP enhanced HIF-1[Formula: see text] accumulation with activation of PI3K/Akt, and induced S1P production by activating Sphk2 via the promotion of HIF-1[Formula: see text]-mediated Sphk2 transcription. In conclusion, BP activated endogenous neuroprotective mechanisms associated with the S1P/HIF-1 pathway and helped protect neuronal cells against hypoxia/ischemia.

Download Full-text

Pharmacological connection of Histamine-1 (H1) Receptor Mediated Neuroprotective mechanism of Ischemic preconditioning in rat

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00479 ◽

2021 ◽

pp. 2717-2722

Author(s):

Prabhat Singh ◽

Bhupesh Sharma

Keyword(s):

Cerebral Ischemia ◽

Cerebral Infarction ◽

Ischemic Preconditioning ◽

Ischemia Reperfusion ◽

Cerebral Injury ◽

Cerebral Stroke ◽

H1 Receptor ◽

Neuroprotective Effects ◽

Motor Incoordination ◽

Nitrite Nitrate

Cerebral ischemia and ischemia-reperfusion is an essential contributor to acute cerebral stroke. Ischemic preconditioning (IPC) has been proven to provide neuroprotection in ischemia-reperfusion injury in rats, but their mechanism behind neuroprotection in cerebral stroke are still unclear. Central histaminergic pathway has crucial role in the pathogenesis of cerebral stroke, but their neuroprotective role in IPC is still unidentified. This research explores the role of histamine-1 receptor in IPC induced neuroprotection against ischemia-reperfusion induced cerebral injury. Rat were subjected to 17 min of global cerebral ischemia (GCI) by occluding both carotid arteries followed by reperfusion for 24 h, to produce ischemia-reperfusion induced cerebral injury. TTC staining was used to measure cerebral infarct size. Morris water maze test was used to assess memory. Inclined beam-walk, hanging wire, lateral push and rota-rod tests were used to assess degree of motor incoordination. Brain acetylcholinesterase activity, nitrite/nitrate, glutathione, TBARS and MPO levels were also examined. GCI has produced a significant increase in cerebral infarction, brain nitrite/nitrate, MPO, TBARS and AChE activity along with a reduction in glutathione content. Impairment of memory and motor coordination were also noted in GCI induced rat. IPC was employed that consist of 3 preceding episodes of ischemia (1 min) and reperfusion (1 min) both immediately before GCI significantly decreased cerebral infarction, motor incoordination, memory impairment and biochemical impairment. Pretreatment with L-histidine mimicked the neuroprotective effects of IPC. L-histidine induced neuroprotection were significantly abolished by chlorpheniramine, a H1 receptor antagonist. We conclude that neuroprotective effects of IPC, probably occurs through the central histaminergic pathway, and histamine-1 receptor could be a new target behind the neuroprotective mechanism of IPC.

Download Full-text