UBIAD1 protects against oxygen-glucose deprivation/reperfusion-induced multiple subcellular organelles injury through PI3K/AKT pathway in N2A cells

UBIAD1 effectively alleviated myocardial ischemia reperfusion injury by activating SIRT1/PGC1α

BACKGROUND AND OBJECTIVES

Myocardial ischemia-reperfusion injury (MIRI) threatens global health and lowers people's sense of happiness. Till now, the mechanism of MIRI has not been well-understood. Therefore, this study was designed to explore the role of UBIAD1 in MIRI as well as its detailed reaction mechanism.

METHODS

The mRNA and protein expressions of UBIAD1 before or after transfection were measured using RT-qPCR and western blot. Western blot was also adopted to measure the expressions of signaling pathway-, mitochondrial damage- and apoptosis-related proteins. Moreover, mitochondrial membrane potential and ATP level were verified by JC-1 immunofluorescence and ATP kits, respectively. With the application of CCK-8, LDH and CK-MB assays, the cell viability, LDH and CK-MB levels were evaluated, respectively. In addition, the cell apoptosis was detected using TUNEL. Finally, the expressions of ROS, SOD, MDA and CAT were measured using DCFH-DA, SOD, MDA and CAT assays, respectively.

RESULTS

In the present study, we found that UBIAD1 was downregulated in hypoxia-reoxygenation (H/R) -induced H9C2 cells and its upregulation could activate SIRT1/PGC1α signaling pathway. It was also found that UBIAD1 regulated mitochondrial membrane potential and ATP level via activating SIRT1/PGC1α signaling pathway. In addition, the injury of H/R-induced H9C2 cells could be relieved by UBIAD1 through the activation of SIRT1/PGC1α signaling pathway. Moreover, UBIAD1 exhibited inhibitory effects on apoptosis and oxidative stress of H/R-induced H9C2 cells through activating SIRT1/PGC1α signaling pathway.

CONCLUSION

To sum up, UBIAD1 could alleviate apoptosis, oxidative stress and H9C2 cell injury by activating SIRT1/PGC1α, which laid experimental foundation for the clinical treatment of MIRI.

UBIAD1 and CoQ10 protect melanoma cells from lipid peroxidation-mediated cell death

Cutaneous melanoma is the deadliest type of skin cancer, although it accounts for a minority of all skin cancers. Oxidative stress is involved in all stages of melanomagenesis and cutaneous melanoma can sustain a much higher load of Reactive Oxygen Species (ROS) than normal tissues. Melanoma cells exploit specific antioxidant machinery to support redox homeostasis. The enzyme UBIA prenyltransferase domain-containing protein 1 (UBIAD1) is responsible for the biosynthesis of non-mitochondrial CoQ10 and plays an important role as antioxidant enzyme. Whether UBIAD1 is involved in melanoma progression has not been addressed, yet. Here, we provide evidence that UBIAD1 expression is associated with poor overall survival (OS) in human melanoma patients. Furthermore, UBIAD1 and CoQ10 levels are upregulated in melanoma cells with respect to melanocytes. We show that UBIAD1 and plasma membrane CoQ10 sustain melanoma cell survival and proliferation by preventing lipid peroxidation and cell death. Additionally, we show that the NAD(P)H Quinone Dehydrogenase 1 (NQO1), responsible for the 2-electron reduction of CoQ10 on plasma membranes, acts downstream of UBIAD1 to support melanoma survival. By showing that the CoQ10-producing enzyme UBIAD1 counteracts oxidative stress and lipid peroxidation events in cutaneous melanoma, this work may open to new therapeutic investigations based on UBIAD1/CoQ10 loss to cure melanoma.

UBIAD1 alleviates ferroptotic neuronal death by enhancing antioxidative capacity by cooperatively restoring impaired mitochondria and Golgi apparatus upon cerebral ischemic/reperfusion insult

Background

Neuronal death due to over-oxidative stress responses defines the pathology of cerebral ischemic/reperfusion (I/R) insult. Ferroptosis is a form of oxidative cell death that is induced by disruption of the balance between antioxidants and pro-oxidants in cells. However, the potential mechanisms responsible for cerebral I/R-induced ferroptotic neuronal death have not been conclusively determined. UBIAD1, is a newly identified antioxidant enzyme that catalyzes coenzyme Q10 (CoQ10) and vitamin K2 biosynthesis in the Golgi apparatus membrane and mitochondria, respectively. Even though UBIAD1 is a significant mediator of apoptosis in cerebral I/R challenge, its roles in ferroptotic neuronal death remain undefined. Therefore, we investigated whether ferroptotic neuronal death is involved in cerebral I/R injury. Further, we evaluated the functions and possible mechanisms of UBIAD1 in cerebral I/R-induced ferroptotic neuronal death, with a major focus on mitochondrial and Golgi apparatus dysfunctions.

Results

Ferroptosis occurred in cerebral I/R. Ferroptotic neuronal death promoted cerebral I/R-induced brain tissue injury and neuronal impairment. UBIAD1 was expressed in cerebral tissues and was localized in neurons, astrocytes, and microglia. Under cerebral I/R conditions overexpressed UBIAD1 significantly suppressed lipid peroxidation and ferroptosis. Moreover, upregulated UBIAD1 protected against brain tissue damage and neuronal death by alleviating I/R-mediated lipid peroxidation and ferroptosis. However, UBIAD1 knockdown reversed these changes. Enhanced UBIAD1-mediated ferroptosis elevated the antioxidative capacity by rescuing mitochondrial and Golgi apparatus dysfunction in cerebral I/R-mediated neuronal injury. They improved the morphology and biofunctions of the mitochondria and Golgi apparatus, thereby elevating the levels of SOD, T-AOC and production of CoQ10, endothelial nitric oxide synthase (eNOS)-regulated nitric oxide (NO) generation as well as suppressed MDA generation.

Conclusions

The neuroprotective agent, UBIAD1, modulates I/R-mediated ferroptosis by restoring mitochondrial and Golgi apparatus dysfunction in damaged brain tissues and neurons, thereby enhancing antioxidative capacities. Moreover, the rescue of impaired mitochondrial and Golgi apparatus as a possible mechanism of regulating ferroptotic neuronal death is a potential treatment strategy for ischemic stroke.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-022-00776-9.

Nonfreezing Low Temperature Maintains the Viability of Menstrual Blood-Derived Endometrial Stem Cells Under Oxygen-Glucose Deprivation Through the Sustained Release of Autophagy-Produced Energy

Between the completion of the mesenchymal stem cell (MSCs) preparation and the transplantation into the patient, there is a time interval during which the quality control and transport of MSC products occur, which usually involves suspending the cells in normal saline in an oxygen-glucose deprivation (OGD) microenvironments. Thus, how to effectively maintain MSC viability during the abovementioned time interval is bound to play a significant role in the therapeutic effect of MSC-based therapies. Recently, menstrual blood-derived endometrial stem cells (MenSCs) have attracted extensive attention in regenerative medicine due to their superior biological characteristics, including noninvasive protocols for their collection, abundant source material, stable donation, and autotransplantation. Therefore, this study aimed to mainly determine the effect of storage temperature on the maintenance of MenSC viabilities in an OGD microenvironment, and to preliminarily explore its potential mechanism. Simultaneously, the effects of solvents commonly used in the clinic on MenSC viability were also examined to support the clinical application of MenSCs. Consequently, our results demonstrated that in the OGD microenvironment, a nonfreezing low temperature (4°C) was suitable and cost-effective for MenSC storage, and the maintenance of MenSC viability stored at 4°C was partly contributed by the sustained releases of autophagy-produced energy. Furthermore, the addition of human serum albumin effectively inhibited the cell sedimentations in the MenSC suspension. These results provide support and practical experience for the extensive application of MenSCs in the clinic.

NAC antagonizes arsenic-induced neurotoxicity through TMEM179 by inhibiting oxidative stress in Oli-neu cells

Arsenic is one of the most common environmental pollutants. Neurotoxicity induced by arsenic has become a major public health concern. However, the effects of arsenic-induced neurotoxicity in the brain and the underlying molecular mechanisms are not well understood. N-acetyl-cysteine (NAC) is a thiol-based antioxidant that can antagonize heavy metal-induced neurotoxicity by scavenging reactive oxygen species (ROS). Here, we used the mouse oligodendrocyte precursor cell (OPC) line Oli-neu to explore the neurotoxic effects of arsenic and the protective effects of NAC. We found that arsenic exposure decreased cell viability, increased oxidative stress, caused mitochondrial dysfunction, and led to apoptosis of Oli-neu cells. Furthermore, we revealed that NAC treatment reversed these neurotoxic effects of arsenic. TMEM179, a key membrane protein, was found highly expressed in OPCs and to be an important factor in maintaining mitochondrial functions. We found that TMEM179 played a critical role in mediating the neurotoxic effects of arsenic and the protective role of NAC. PKCβ is a downstream factor through which TMEM179 regulates the expression of apoptosis-related proteins. This study improves our understanding of the neurotoxic effects and mechanisms of arsenic exposure and the protective effects of NAC. It also identifies a potential molecular target, TMEM179, for the treatment of arsenic-induced neurotoxicity.

Functional study of SCCD pathogenic gene UBIAD1 (Review)

Schnyder's crystalline corneal dystrophy (SCCD) is a rare autosomal dominant genetic disorder that is characterized by progressive corneal opacity, owing to aberrant accumulation of cholesterol and phospholipids in the cornea. A number of SCCD affected families have been reported in the world since 1924, when it was first described. In 2007, the molecular basis of SCCD was demonstrated to be associated with a tumor suppressor, UbiA prenyltransferase domain-containing 1 (UBIAD1), which was isolated from the bladder mucosa and demonstrated to be involved in vitamin K₂ and CoQ10 biosynthesis. This sterol triggers the binding of UBIAD1 to 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR) at endoplasmic reticulum (ER) membranes, which is regulated by an intracellular geranylgeranyl diphosphate (GGpp) molecule. The inability of SCCD-associated UBIAD1 to bind GGpp results in the consistent binding of UBIAD1 to HMGCR at ER membranes. This binding leads to HMGCRs being redundant. Therefore, they cannot be degraded through ER-associated degradation to synthesize abundant cholesterol in tissue cells. Excess corneal cholesterol accumulation thus leads to SCCD disease. After decades, the efforts of numerous ophthalmologists and scientists have helped clarify the molecular basis and pathogenesis of SCCD, which has guided the effective diagnosis and treatment of this genetic disorder. However, more studies need to be conducted to understand the pathogenesis of SCCD disease from a genetic basis by studying the defective gene, UBIAD1. Results would guide effective diagnosis and treatment of the inherited eye disease.

Propofol Pretreatment Prevents Oxygen-Glucose Deprivation/Reoxygenation (OGD/R)-induced Inflammation Through Nuclear Transcription Factor κB (NF-κB) Pathway in Neuroblastoma Cells

BACKGROUND

Inflammation is one of the causes of neuroblastoma progression. Propofol attenuates inflammation by repressing nuclear transcription factor κB (NF-κB) in different diseases. But its effect on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced inflammation is not known.

OBJECTIVE

This study investigated the role and mechanism of action of propofol on OGD/Rinduced inflammation in mouse N2A neuroblastoma cells.

METHODS

MTT was performed on mouse neuroblastoma cells N2A to assess and select the maximum safe dose of propofol. Next, N2A cells were pretreated with propofol and then, exposed to the OGD condition for 3 h and reoxygenated for 6 h. The content of the inflammatory factors, interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α), in the medium was measured by ELISA, while their protein expression was detected by western blot and immunofluorescence. The protein expression of P65, p-P65, IKBα and p-IKBα belonging to the NF-κB pathway was also determined by western blot in N2A cells. To further confirm the mechanism of propofol on OGD/R-induced inflammation in mouse N2A cells, P65 was over-expressed and the above experiments were repeated.

RESULTS

Propofol did not affect cell viability of N2A cells even at the maximum concentration used (30 µM), thus, 30 µM of propofol was selected to perform our experiments. Besides, OGD/R induced inflammation and activation of NF-κB pathway with increased p-P65 and p-IKBα expression, and propofol pretreatment inhibited OGD/R induced inflammation and activation of NF-κB pathway in N2A cells. Over-expression of P56 abolished the effects of propofol on OGD/Rinduced inflammation and activation of NF-κB pathway in N2A cells.

CONCLUSION

Our work demonstrated for the first time that propofol pretreatment ameliorated OGD/R induced inflammation via NF-κB pathway modulation in mouse neuroblastoma N2A cells, indicating that propofol might be considered as a potential therapeutic approach to reduce inflammation in neuroblastoma.

L-3-n-butylphthalide promotes restoration after an experimental animal model of intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating type of stroke with high morbidity and mortality, and the effective therapies for ICH remain to be explored. L-3-n-butylphthalide (NBP) is widely used in the treatment of ischemic stroke. However, few studies evaluated the therapeutic effects of NBP on ICH. Therefore, the present study aims to evaluate the effects of NBP on ICH and its potential mechanism. The rats were randomly divided into sham-operated group, saline-treated (ICH + saline) group, and NBP-treated (ICH + NBP) group. The ICH model of SD rats induced by IV collagenase was established. The modified Garcia JH score was used to detect the neurological deficit in rats. Western Blot and immunohistochemistry analysis was applied to test the levels of UBIAD1 and caspase-3 expressions in the perihematomal region. The rates of apoptotic cells were detected by TUNEL staining. The results showed that NBP up-regulated the expression of UBIAD1, reduced the apoptotic cells in the perihematomal region, and improved the neurological deficit. Taken together, our study added some new evidence to the application of NBP in ICH treatment.

Silencing PAQR3 protects against oxygen-glucose deprivation/reperfusion-induced neuronal apoptosis via activation of PI3K/AKT signaling in PC12 cells

AIMS

Neuronal apoptosis acts as the pivotal pathogenesis of cerebral ischemia/reperfusion (I/R) injury after ischemic stroke. PAQR3 (progestin and adipoQ receptor family member 3) is a crucial player who participates in the regulation of cell death. We aim to explore the specific function and the underlying mechanism of PAQR3 in cerebral I/R induced neuronal injury.

MAIN METHODS

We established a mouse middle cerebral artery occlusion/reperfusion (MCAO/R) model and rat adrenal pheochromocytoma (PC12) cell oxygen-glucose deprivation/reperfusion (OGD/R) model to detect the expression and of PAQR3 after I/R treatment in vivo and in vitro. We used lentivirus to knockdown PAQR3 and investigated the function of PAQR3 in I/R induced neuronal apoptosis.

KEY FINDINGS

PAQR3 expression is markedly increased in the ischemic hemisphere of C57BL/6 mice and PC12 cells after I/R stimulation. Knockdown PAQR3 can attenuate neuronal apoptosis induced by I/R in PC12 cells and exerts neuroprotective effects. PAQR3 deficiency can significantly raise cell viability and suppress LDH leakage under I/R treatment. Silencing PAQR3 attenuates neuronal apoptosis remarkably with fewer TUNEL-positive cells and lower apoptosis rate under I/R treatment. Mechanistically, knockdown of PAQR3 can inhibit the apoptosis pathway through inducing anti-apoptotic proteins and inhibiting pro-apoptotic proteins. Besides, PI3K/AKT signaling suppression with LY294002 abolished the neuroprotective functions induced by silencing PAQR3.

SIGNIFICANCE

Our results elucidate that silencing PAQR3 can protect PC12 from OGD/R injury via activating PI3K/AKT pathway. And therefore, provide a novel therapeutic target for the prevention of cerebral I/R injury.

Olfactory Mucosa Mesenchymal Stem Cells Ameliorate Cerebral Ischemic/Reperfusion Injury Through Modulation of UBIAD1 Expression

Mesenchymal stem cells (MSCs) have presented a promising neuroprotective effect in cerebral ischemia/reperfusion (I/R). Olfactory mucosa MSCs (OM-MSCs), a novel source of MSCs located in the human nasal cavity, are easy to obtain and situated for autologous transplantation. The present study was designed to evaluate the neuroprotective effects of OM-MSCs on cerebral I/R injury and the possible mechanisms. In the transient middle cerebral artery occlusion (t-MCAO) model, excessive oxidative stress and increased swollen mitochondria were observed in the peri-infarct cortex. Intravenous injection of OM-MSCs ameliorated mitochondrial damage and restored oxidant/antioxidant imbalance. Using the oxygen glucose deprivation/reperfusion (OGD/R) model in vitro, we discovered that the exposure of mouse neuroblastoma N2a cells to OGD/R triggers excessive reactive oxygen species (ROS) generation and induces mitochondrial deterioration with decreased mitochondrial membrane potential and reduces ATP content. OM-MSC transwell coculture attenuated the above perturbations accompanied with increased UbiA prenyltransferase domain-containing 1 (UBIAD1) expression, whereas these protective effects of OM-MSCs were blocked when UBIAD1 was knocked down. UBIAD1-specific small interfering RNA (siRNA) reversed the increased membrane potential and ATP content promoted by OM-MSCs. Additionally, UBIAD1-specific siRNA blocked the oxidant/antioxidant balance treated by OM-MSCs. Overall, our results suggested that OM-MSCs exert neuroprotective effects in cerebral I/R injury by attenuating mitochondrial dysfunction and enhancing antioxidation via upregulation of UBIAD1.

Olfactory Mucosa Mesenchymal Stem Cells Alleviate Cerebral Ischemia/Reperfusion Injury Via Golgi Apparatus Secretory Pathway Ca2+ -ATPase Isoform1

Olfactory mucosa mesenchymal stem cells (OM-MSCs) have exhibited their effectiveness in central nervous system diseases and provided an appealing candidate for the treatment of ischemic stroke. Previous evidence have shown that Golgi apparatus (GA) secretory pathway Ca²⁺-ATPase isoform1 (SPCA1) was a potential therapeutic target for ischemic stroke. In this study, we explored the neuroprotective mechanism of OM-MSCs and its effect on the expression and function of SPCA1 during cerebral ischemia/reperfusion. Based on in vitro and in vivo experiments, we discovered that OM-MSCs attenuated apoptosis and oxidative stress in ischemic stroke models, reduced the cerebral infarction volume, and improved the neurologic deficits of rats. OM-MSCs also upregulated SPCA1 expression and alleviated Ca²⁺ overload and decreased the edema and dissolution of the GA in neurons. Moreover, we discovered that SPCA1 depletion in oxygen and glucose deprivation/reoxygenation (OGD/R)-treated N2a cells mitigated the protective effects of OM-MSCs. Altogether, OM-MSCs exerted neuroprotective effects in ischemic stroke probably via modulating SPCA1 and reducing the edema and dissolution of the GA in neurons.

PAQR3 protects against oxygen-glucose deprivation/reperfusion-induced injury through the ERK signaling pathway in N2A cells

Cerebral ischemia-reperfusion injury is pivotal in the development of multiple-subcellular organelle and tissue injury after acute ischemic stroke. Recently, the Golgi apparatus (GA) has been shown to be a key subcellular organelle that plays an important role in neuroprotection against oxygen-glucose deprivation/reperfusion (OGD/R) injury. PAQR3, a scaffold protein exclusively localized in the GA, was originally discovered as a potential tumor suppressor protein. PAQR3 acts as a spatial regulator of Raf-1 that binds Raf-1 and sequesters it to the GA, where it negatively modulates the Ras/Raf/MEK/ERK signaling pathway in tumor models. Studies suggest that suppression of the ERK pathway can alleviate OGD/R-induced cell apoptosis. However, whether PAQR3 has potential effects on ischemic stroke and the underlying mechanism(s) remain unexplored. The current study is the first to show that PAQR3 was significantly downregulated in mouse neuroblastoma (N2A) cells upon OGD/R exposure, both at the mRNA and protein levels. Compared to that in controls, the mRNA level of PAQR3 began to decline at 0 h (0 h) after reperfusion, while the protein level began to decline at 4 h. Furthermore, overexpression of PAQR3 reduced OGD/R-induced apoptosis. The mRNA and protein levels of total ERK1 and ERK2 were unaltered, while activated p-ERK1 and p-ERK2 were decreased in N2A cells transfected with a PAQR3 expression vector after OGD for 4 h plus 24 h of reperfusion. Collectively, these data indicated that increased PAQR3 expression protected against OGD/R-induced apoptosis possibly by inhibiting the ERK signaling pathway. Therefore, PAQR3 might be a new attractive target in the treatment of OGD/R insult, and the underlying mechanism will pave the way for its potential experimental and clinical application.

Protective effects of vitamin K2 on 6-OHDA-induced apoptosis in PC12 cells through modulation bax and caspase-3 activation

Neuroprotection using compounds with dual functions of anti-apoptotic and antioxidant effects fight against neurodegeneration. Vitamin K2 acts as a cofactor in many biochemical pathways, including sphingolipid synthesis in the nervous system, which is involved in many cellular events, including proliferation, differentiation, cellular communication, and alteration. This study aimed to investigate the protective effects of vitamin K2 in PC12 cells as an in vitro model of Parkinson's disease. The protective effects of vitamin K2 against 6-OHDA-induced apoptosis in PC12 cells were assessed using resazurin for viability, DCF-DA for ROS level, DTNB for glutathione level, flow cytometry for sub G1, and western blot analysis for detecting bax and pro-caspase-3 expression level. The results showed that 6-OHDA significantly decreased cell viability, glutathione and pro-caspase-3 levels, and increased ROS, the amount of bax in PC12 cells, while the pretreatment with 5 μM vitamin K2 significantly decreased the cell death induced by 6-OHDA. Generally, the results may present a new insight about the potential protective action of vitamin K2 against the progression of Parkinson's disease. Further studies may warrant the use of vitamin K2 as an antioxidant and anti-apoptotic agent in slowing nerve injury in neurodegenerative disease, particularly in Parkinson's disease.

Expression and regulation of miR-449a and AREG in cerebral ischemic injury

Rodent focal ischemia models are widely used to mimic and examine human strokes. To the best of our knowledge, no investigation has systematically examined the expression changes of microRNA (miR)-449a and Amphiregulin (AREG) as well as their biological relationship during middle cerebral artery occlusion (MCAO) and oxygen and glucose deprivation/reperfusion (OGD/R). The present study examined the histological and behavioral outcomes of MCAO and the function of miR-449a and AREG in cerebral ischemic injury. Rats were subjected to 2 h MCAO, which was followed by reperfusion. miR-449a and AREG were examined in the injury tissues of MCAO rats and the OGD/R cell line by reverse transcription-quantitative polymerase chain reaction. Protein expressions of AREG in the injury tissues of MCAO rats was measured using an immunohistochemistry and the protein expression levels of AREG, epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (Akt) and the phosphorylation level of Akt (p-Akt) were analyzed by western blotting. Cell apoptosis was examined following the knock down and subsequent overexpression of AREG in a human OGD/R neuronal cell line by small interfering RNAs (siRNAs) and plasmid transfection. Luciferase reporter assays were used to validate the target of miR-449a. The expression changes and regulatory mechanisms of miR-449a and AREG in an ischemia/reperfusion (I/R) injury model were examined in vivo and in vitro. The neurological deficit score, brain edema volume, cerebral infarct area, and the number of apoptosis cells in ischemic rats were all markedly elevated, than that in the control rats. The expression of miR-449a was decreased and AREG was increased in the MCAO rats and human OGD/R neuronal cell line. miR-449a inhibition or AREG overexpression in OGD/R cells resulted in a significant decrease in apoptotic cells, and AREG was revealed to be one of the direct targets of miR-449a. Molecular recovery was observed following transfection with miR-449a mimics and AREG knockdown in an OGD/R model in vitro. The present study demonstrated that miR-449a was downregulated while AREG was upregulated in cerebral ischemic injury, and the recovery of neurological function can be obtained following the overexpression of miR-449a and the knockdown of AREG in an I/R injury model. miR-449a functions in ischemic stroke via directly targeting AREG. These findings suggest a novel mechanism involving in cerebral I/R injury model and may aid investigators in gaining a deeper understanding of strokes in a clinical setting.

Xingnaojing Injection Protects against Cerebral Ischemia Reperfusion Injury via PI3K/Akt-Mediated eNOS Phosphorylation

Xingnaojing (XNJ) injection, derived from traditional Chinese medicine formulation, has a protective effect against stroke, but the underlying mechanism is unclear, which severely limited its clinical application. This research aims to elucidate the role and mechanism of XNJ in reducing cerebral ischemic reperfusion (I/R) injury. Rats received 2 h cerebral ischemia followed by reperfusion of 24 h and were intraperitoneally given 5, 10, or 15 ml/kg XNJ 24 h before ischemia and at the onset of reperfusion, respectively. TTC staining, HE staining, and neurological score were implied to evaluate the effectiveness of XNJ. The protein expressions of PI3K/Akt and eNOS signaling were measured. Experiments were further performed in human brain microvascular endothelial cells (HBMECs) to investigate the protective mechanisms of XNJ. HBMECs were subjected to 3 h oxygen and glucose deprivation following 24 h of reoxygenation (OGD) to mimic cerebral I/R in vitro. PI3K inhibitor LY294002 was added with or without the preconditioning of XNJ. Multiple methods including western blot, immunofluorescence, DAPI staining, JC-1, and flow cytometry were carried out to evaluate the effect of XNJ on HBMECs. XNJ could improve rat cerebral ischemic injury and OGD induced HBMECs apoptosis. In vivo and in vitro researches indicated that the mechanism might be relevant to the activation of PI3K/Akt/eNOS signaling.