Deferoxamine Reduces Cavity Size in the Brain After Intracerebral Hemorrhage in Aged Rats

Exploring the Neuroprotective Effects of Spirulina platensis: Insights Into Hemorrhagic Volume and Histological Outcomes

Background Hemorrhagic events can result in significant neurological damage, and identifying effective strategies for neuroprotection is crucial. Several studies have directed their attention to the alterations in perilesional parenchymal tissue. These investigations have sought to modify ischemic and metabolic changes by utilizing potential neuroprotective agents and to develop strategies that effectively mitigate secondary perilesional neuronal damage. By gaining a deeper understanding of its mechanisms and efficacy, Spirulina platensis can emerge as a promising therapeutic intervention for various neurological disorders. Methodology This controlled and blinded experimental study was conducted on adult male Wistar rats. The rats were divided into the treatment group, which received Spirulina platensis extract for 30 days before the hemorrhagic event, and the control group, where all animals underwent the same experimental hemorrhage model using collagenase. Each group was divided into the following three subgroups based on the sacrifice time: six hours, 24 hours, and 30 days. The brain section with the largest hemorrhage volume was selected for histological analysis. The number of viable neurons was analyzed in the perilesional zone and the cortical fields along the puncture trajectory. Neurofunctional evaluations were conducted on animals sacrificed 15 and 30 days after the procedure. Results Initial analysis showed no significant difference in viable neurons between groups (p = 0.63). Still, after 24 hours, the treatment group had a significantly higher number of viable neurons per peripheral fields (18.5) compared to the control group (13.4; p < 0.05). Neurofunctional tests at 15 days indicated a trend toward significance in absolute discrimination (p = 0.054), with the control group showing higher mean values (5.5, SD = 3.1) than the treatment group (-1, SD = 5.1). The discrimination index exhibited a significant difference (p < 0.01), with higher mean values in the control group (0.59, SD = 0.34) compared to the treatment group (-0.05, SD = 0.21). No significant differences were found in other neurofunctional parameters at this time point. At 30 days, no significant differences were observed in absolute discrimination, discrimination index, contralateral paw elevation, rearing time, and wire hanging time test (p > 0.1); however, the treatment group presented a better motor performance in the open field test (14.2, SD = 9.02) compared to the control group (5.25, SD = 2.06), approaching significance (p = 0.06). Conclusions The group treated with Spirulina platensis demonstrated significantly more viable neurons in the perilesional fields 24 hours after the induced hemorrhage. The treatment group also had a relatively better motor performance in the open field test 30 days after the hemorrhage (p = 0.06). These findings suggest a potential neuroprotection effect and warrant further investigations to explore the effects of Spirulina platensis and its active component phycocyanin in acute neurological conditions.

HIF-1α and VEGF Are Involved in Deferoxamine-Ameliorated Traumatic Brain Injury

BACKGROUND

Deferoxamine (DFX) has been reported to have neuroprotective effect. This study aimed to investigate the neuroprotective effect of DFX and its effect on hypoxia-inducible factor 1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) in rats after traumatic brain injury (TBI).

MATERIALS AND METHODS

Rats were randomly divided into sham operation, TBI + DFX, and TBI + vehicle groups. The rats in the TBI + DFX group were intraperitoneally injected with DFX 2 and 6 h after injury, thereafter once every 12 h. The rats in the TBI + vehicle group were intraperitoneally injected with saline at the same time points. At 6, 12, 24, and 48 h after TBI, 6 rats in each group were euthanized, and the brains were harvested. The expression of HIF-1α and VEGF in the pericontusional area was detected using real-time polymerase chain reaction and Western blot analysis. TBI-induced apoptosis was investigated using the TdT-mediated dUTP nick-end labeling (TUNEL) method. Three days after TBI, the density of microvessels was examined via immunohistochemical staining.

RESULTS

DFX treatment upregulated the expression of HIF-1α and VEGF after TBI. DFX treatment reduced apoptosis and improved the neurobehavioral score after TBI. The density of microvessels was higher in the TBI + DFX group than that in the TBI + vehicle group 3 d after TBI.

CONCLUSIONS

DFX can stimulate angiogenesis, inhibit apoptosis, and play a protective role after TBI. The protective effect of DFX may, at least in part, be through upregulating the expression of HIF-1α and its downstream target gene VEGF.

Deferoxamine Alleviates Iron Overload and Brain Injury in a Rat Model of Brainstem Hemorrhage

BACKGROUND

Brainstem hemorrhage (BSH) is the most dangerous and devastating subtype of intracerebral hemorrhage and is associated with high morbidity and mortality. However, to date, no effective prevention methods or specific therapies have been available to improve its clinical outcomes. We preliminarily explored the efficacy of deferoxamine (DFO), a clinical chelator known for its iron-scavenging activities, in a rat model of BSH induced with collagenase infusion.

METHODS

DFO or saline was administrated 6 hours after BSH induction and then every 12 hours for ≤7 days. The survival curve of the rats was created, and the neurological scores were examined on days 1, 3, and 7 after BSH. The rats were sacrificed after 1, 3, and 7 days of DFO treatment for histological examination and immunohistochemistry.

RESULTS

The results showed that administration of DFO delayed erythrocytes lysis, reduced iron deposition, reduced reactive oxygen species generation, reduced heme oxygenase-1 expression, and alleviated brain injury such as neuron degeneration and myelin sheath injury. However, DFO did not improve the survival rate and neurobehavioral outcomes in this model.

CONCLUSIONS

Administration of DFO had limited therapeutic effects on collagenase-induced brainstem hemorrhage in rats. Some potential explanations were proposed, and more preclinical work is required to clarify the controversial curative effect of DFO in ICH.

FTY720 attenuates iron deposition and glial responses in improving delayed lesion and long-term outcomes of collagenase-induced intracerebral hemorrhage

Most intracerebral hemorrhage (ICH) survivors have poor long-term outcomes, such as cognitive deficits and depression. Delayed lesions of ICH include neuron loss and white matter injury and the pathology of the lesions involves iron deposition and glial responses, which contribute to depressive-like behavior and cognitive impairment in animals. This study aimed to investigate the effects of FTY720 (0.3 mg/kg/day for 4 weeks) on iron deposition, glial responses, histological abnormalities and behavioral dysfunction in mice with ICH. The primary adverse long-term outcomes in our study of ICH mice were depressive-like behavior and impaired recognition memory. We found that FTY720 safely ameliorated depressive-like behavior and impaired recognition without affecting recovery of grip function and locomotor activity 28 days post-ICH. Moreover, we measured neuron loss, white matter lesions, lesion volume and iron deposition at day 28, which were attenuated in the FTY720-treated group compared to the ICH-control group, without changing initial hematoma volume on day 1 post-ICH. Long-term elevation of glial responses, including microglia activity and astrogliosis with tumor necrosis factor alpha (TNFα) expression was demonstrated by Western blot and immunofluorescence staining, which we found was attenuated by FTY720 treatment. Hence, FTY720 could become a novel therapeutic agent for improving long-term outcomes after ICH.

Serial quantitative neuroimaging of iron in the intracerebral hemorrhage pig model

Iron released after intracerebral hemorrhage (ICH) is damaging to the brain. Measurement of the content and distribution of iron in the hematoma could predict brain damage. In this study, 16 Yorkshire piglets were subjected to autologous blood injection ICH model and studied longitudinally using quantitative susceptibility mapping and R2* relaxivity MRI on day 1 and 7 post-ICH. Phantom calibration of susceptibility demonstrated (1) iron distribution heterogeneity within the hematoma and (2) natural absorption of iron from 154 ± 78 µg/mL (day 1) to 127 ± 33 µg/mL (day 7). R2* in the hematoma decreased at day 7. This method could be adopted for ICH in humans.

Preclinical Studies and Translational Applications of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) which refers to bleeding in the brain is a very deleterious condition with high mortality and disability rate. Surgery or conservative therapy remains the treatment option. Various studies have divided the disease process of ICH into primary and secondary injury, for which knowledge into these processes has yielded many preclinical and clinical treatment options. The aim of this review is to highlight some of the new experimental drugs as well as other treatment options like stem cell therapy, rehabilitation, and nanomedicine and mention some translational clinical applications that have been done with these treatment options.

Intracerebral Hemorrhage: Perihemorrhagic Edema and Secondary Hematoma Expansion: From Bench Work to Ongoing Controversies

Intracerebral hemorrhage (ICH) is a medical emergency, which often leads to severe disability and death. ICH-related poor outcomes are due to primary injury causing structural damage and mass effect and secondary injury in the perihemorrhagic region over several days to weeks. Secondary injury after ICH can be due to hematoma expansion (HE) or a consequence of repair pathway along the continuum of neuroinflammation, neuronal death, and perihemorrhagic edema (PHE). This review article is focused on PHE and HE and will cover the animal studies, related human studies, and clinical trials relating to these mechanisms of secondary brain injury in ICH patients.

Knockout of ho-1 protects the striatum from ferrous iron-induced injury in a male-specific manner in mice

Men have worse survival than premenopausal women after intracerebral hemorrhage (ICH). After ICH, overproduction of iron associated with induction of heme oxygenase-1 (HO-1) in brain was observed. Rodent ICH model using ferrous citrate (FC)-infusion into the striatum to simulate iron overload, showed a higher degree of injury severity in males than in females. However, the participation of HO-1 in sex-differences of iron-induced brain injury remains unknown. The present results showed a higher level of HO-1 expression associated with more severe injury in males compared with females after FC-infusion. Estradiol (E₂) contributed to lower levels of FC-induced HO-1 expression in females compared with males. Heterozygote ho-1 KO decreased the levels of FC-induced injury severity, histological lesions, behavioral deficits, autophagy and autophagic cell death in the striatum of males but not in females. Moreover, ho-1 deficiency enhanced the neuroprotection by E₂ only in males. These results suggested that over induction of HO-1 plays a harmful role in FC-induced brain injury in a male-specific manner. Suppression of HO-1 combined with E₂ exhibits a synergistic effect on neuroprotection against FC-induced striatal injury in males. These findings open up the prospect for male-specific neuroprotection targeting HO-1 suppression for patients suffering from striatal iron overload.

Microglial Polarization and Inflammatory Mediators After Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and morbidity. When a diseased artery within the brain bursts, expansion and absorption of the resulting hematoma trigger a series of reactions that cause primary and secondary brain injury. Microglia are extremely important for removing the hematoma and clearing debris, but they are also a source of ongoing inflammation. This article discusses the role of microglial activation/polarization and related inflammatory mediators, such as Toll-like receptor 4, matrix metalloproteinases, high-mobility group protein box-1, nuclear factor erythroid 2-related factor 2, heme oxygenase, and iron, in secondary injury after ICH and highlights the potential targets for ICH treatment.

Curcumin attenuates brain edema in mice with intracerebral hemorrhage through inhibition of AQP4 and AQP9 expression

AIM

Aquaporins (AQPs) are the water-channels that play important roles in brain water homeostasis and in cerebral edema induced by brain injury. In this study we investigated the relationship between AQPs and a neuroprotective agent curcumin that was effective in the treatment of brain edema in mice with intracerebral hemorrhage (ICH).

METHODS

ICH was induced in mice by autologous blood infusion. The mice immediately received curcumin (75, 150, 300 mg/kg, ip). The Rotarod test scores, brain water content and brain expression of AQPs were measured post ICH. Cultured primary mouse astrocytes were used for in vitro experiments. The expression of AQP1, AQP4 and AQP9 and NF-κB p65 were detected using Western blotting or immunochemistry staining.

RESULTS

Curcumin administration dose-dependently reduced the cerebral edema at d 3 post ICH, and significantly attenuated the neurological deficits at d 5 post ICH. Furthermore, curcumin dose-dependently decreased the gene and protein expression of AQP4 and AQP9, but not AQP1 post ICH. Treatment of the cultured astrocytes with Fe(2+) (10-100 μmol/L) dose-dependently increased the expression and nuclear translocation of NF-κB p65 and the expression of AQP4 and AQP9, which were partly blocked by co-treatment with curcumin (20 μmol/L) or the NF-κB inhibitor PDTC (10 μmol/L).

CONCLUSION

Curcumin effectively attenuates brain edema in mice with ICH through inhibition of the NF-κB pathway and subsequently the expression of AQP4 and AQP9. Curcumin may serve as a potential therapeutic agent for ICH.

Efficacy of deferoxamine in animal models of intracerebral hemorrhage: a systematic review and stratified meta-analysis

Intracerebral hemorrhage (ICH) is a subtype of stroke associated with high morbidity and mortality rates. No proven treatments are available for this condition. Iron-mediated free radical injury is associated with secondary damage following ICH. Deferoxamine (DFX), a ferric-iron chelator, is a candidate drug for the treatment of ICH. We performed a systematic review of studies involving the administration of DFX following ICH. In total, 20 studies were identified that described the efficacy of DFX in animal models of ICH and assessed changes in the brain water content, neurobehavioral score, or both. DFX reduced the brain water content by 85.7% in animal models of ICH (-0.86, 95% CI: -.48- -0.23; P < 0.01; 23 comparisons), and improved the neurobehavioral score by -1.08 (95% CI: -1.23- -0.92; P < 0.01; 62 comparisons). DFX was most efficacious when administered 2–4 h after ICH at a dose of 10–50 mg/kg depending on species, and this beneficial effect remained for up to 24 h postinjury. The efficacy was higher with phenobarbital anesthesia, intramuscular injection, and lysed erythrocyte infusion, and in Fischer 344 rats or aged animals. Overall, although DFX was found to be effective in experimental ICH, additional confirmation is needed due to possible publication bias, poor study quality, and the limited number of studies conducting clinical trials.

Intracerebral hemorrhage in mouse models: therapeutic interventions and functional recovery

There has been strong pre-clinical research on mechanisms of initial cell death and tissue injury in intracerebral hemorrhage (ICH). This data has led to the evaluation of several therapeutics for neuroprotection or the mitigation of early tissue damage. Most of these studies have been done in the rat. Also, there has been little study of the mechanisms of tissue repair and recovery. This review examines the testing of candidate therapeutics in mouse models of ICH for their effect on tissue protection and repair. This review will help the readers compare it to the extensively researched rat model of ICH and thus enhance work that are pending in mouse model.

Emerging experimental therapies for intracerebral hemorrhage: targeting mechanisms of secondary brain injury

Intracerebral hemorrhage (ICH) is associated with a higher degree of morbidity and mortality than other stroke subtypes. Despite this burden, currently approved treatments have demonstrated limited efficacy. To date, therapeutic strategies have principally targeted hematoma expansion and resultant mass effect. However, secondary mechanisms of brain injury are believed to be critical effectors of cell death and neurological outcome following ICH. This article reviews the pathophysiology of secondary brain injury relevant to ICH, examines pertinent experimental models, and highlights emerging therapeutic strategies. Treatment paradigms discussed include thrombin inhibitors, deferoxamine, minocycline, statins, granulocyte-colony stimulating factors, and therapeutic hypothermia. Despite promising experimental and preliminary human data, further studies are warranted prior to effective clinical translation.