Diagnosis and Management of Spontaneous Intracerebral Hemorrhage

Mechanism of Stat1 in the neuronal Ca2+ overload after intracerebral hemorrhage via the H3K27ac/Trpm7 axis

Intracerebral hemorrhage (ICH) is classified as a subtype of stroke and Calcium (Ca²⁺) overload is a catalyst for ICH. This study explored the mechanisms of Stat1 (signal transducer and activator of transcription 1) in the neuronal Ca²⁺ overload after ICH. ICH mouse models and in vitro cell models were established. Stat1 and transient receptor potential melastatin 7 (Trpm7) were detected up-regulated in ICH models. Afterwards, the mice were infected with the lentivirus containing sh-Stat1, and HT22 cells were treated with si-Stat1 and the lentivirus containing pcDNA3.1-Trpm7. The neurologic functional impairment, histopathological damage, and Nissl body in mice were all measured. HT22 cell viability and apoptosis were identified. The levels of Ca²⁺, Trpm7 mRNA, H3K27 acetylation (H3K27ac), CaMKII-α, and p-Stat1 protein in the tissues and cells were determined. We found that silencing Stat1 alleviated ICH damage and repressed the neuronal Ca²⁺ overload after ICH. H3K27ac enrichment in the Trpm7 promoter region was examined and we found that p-Stat1 accelerated Trpm7 transcription via promoting H3K27ac in the Trpm7 promoter region. Besides, Trpm7 overexpression increased Ca²⁺ overload and aggravated ICH. Overall, p-Stat1 promoted Trpm7 transcription and further aggravated the Ca²⁺ overload after ICH.

Stroke in Pregnancy: A Focused Update

Ischemic stroke (IS) and hemorrhagic stroke (HS) can be devastating complications during pregnancy and the puerperium that are thought to occur in approximately 30 in 100,000 pregnancies. In high-risk groups, such as women with preeclampsia, the incidence of both stroke subtypes, combined, is up to 6-fold higher than in pregnant women without these disorders. IS or HS may present in young women with atypical symptoms including headache, seizure, extremity weakness, dizziness, nausea, behavioral changes, and visual symptoms. Obstetric anesthesiologists who recognize these signs and symptoms of pregnancy-related stroke are well positioned to facilitate timely care. Acute stroke of any type is an emergency that should prompt immediate coordination of care between obstetric anesthesiologists, stroke neurologists, high-risk obstetricians, nurses, and neonatologists. Historically, guidelines have not addressed the unique situation of maternal stroke, and pregnant women have been excluded from the large stroke trials. More recently, several publications and professional societies have highlighted that pregnant women suspected of having IS or HS should be evaluated for the same therapies as nonpregnant women. Vaginal delivery is generally preferred unless there are obstetric indications for cesarean delivery. Neuraxial analgesia and anesthesia are frequently safer than general anesthesia for cesarean delivery in the patient with a recent stroke. Potential exceptions include therapeutic anticoagulation or intracranial hypertension with risk of herniation. General anesthesia may be appropriate when cesarean delivery will be combined with intracranial neurosurgery.

The role of heme oxygenase-1 (HO-1) in the regulation of inflammatory reaction, neuronal cell proliferation and apoptosis in rats after intracerebral hemorrhage (ICH)

OBJECTIVE

To investigate the role of heme oxygenase-1 (HO-1) in the regulation of inflammatory reaction, neuronal cell proliferation and apoptosis in rats after intracerebral hemorrhage (ICH).

METHODS

Thirty-six adult Sprague Dawley (SD) male rats were randomly divided into sham operation, ICH and zinc protoporphyrin (ZPP) group. Rats (except for the sham operation group) were given 50 μL stereotactic injection of autologous blood from the femoral artery into the caudate nucleus, to establish an ICH model. In addition, rats in the ZPP group were given 10 mg/kg intraperitoneal injection of ZPP. At day 3 postoperative, neurobehavioral changes and brain water content were evaluated, brain tissue HO-1 expression was detected with immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR), brain tissue apoptosis was evaluated with TUNEL method, Caspase 3, Caspase 8 and Caspase 9 activity were detected with colorimetric method, level of TNF-α, IL-1β, IL-6 and IL-8 were measured with the enzyme-linked immunosorbent assay (ELISA), while Bcl-2, Bax, p-NF-κB p65 and p-IκBα protein expression were detected with Western blot.

RESULTS

ICH group compared to sham operation: HO-1 positive rate and mRNA expression were increased, neurological deficit score and cell apoptosis rate were increased, Caspase 3, Caspase 8 and Caspase 9 activity were increased, level of TNF-α, IL-1β, IL-6 and IL-8 were increased, Bcl-2 expression was downregulated, Bax, p-NF-κB p65 and p-IκBα expression were upregulated. The differences were statistically significant (P<0.01). ZPP group compared to ICH: HO-1 positive rate and mRNA expression were decreased, neurological deficit score and cell apoptosis rate were decreased, Caspase 3, Caspase 8, Caspase 9 activity were decreased, level of TNF-α, IL-1β, IL-6 and IL-8 were decreased, Bcl-2 expression was upregulated, Bax, p-NF-κB p65 and p-IκBα expression were downregulated, and the differences were statistically significant (P<0.01).

CONCLUSION

HO-1 inhibitor, ZPP does have a protective effect on ICH rats. This might be due to its inhibition to the inflammatory reaction and neuronal cell apoptosis.