Acute Treatment With Herbal Extracts Provides Neuroprotective Benefits in In Vitro and In Vivo Stroke Models, Characterized by Reduced Ischemic Cell Death and Maintenance of Motor and Neurological Functions

Pathophysiology of cerebral ischemia-reperfusion injury: An overview of oxidative stress and plant-based therapeutic approaches

Stroke is a debilitating neurological disorder that causes substantial morbidity and mortality on a global scale. Ischemic stroke, the most common type, occurs when the brain's blood supply is interrupted. Oxidative stress is a key factor in stroke pathology, contributing to inflammation and neuronal cell death. As a result, there is increasing interest in the potential of plant extracts, which have been used in traditional medicine for centuries and are generally considered safe, to serve as alternative or complementary treatments for stroke. The plant extracts can target multiple pathological processes, including oxidative stress, offering neuroprotective effects. The development of highly efficient, low-toxicity, and cost-effective natural products is crucial for enhancing stroke treatment options. In this review, we examine 60 plant extracts that have been focused on the studies published from year 2000 to 2024 along with the studies' experimental models, dosages, and results. The plant extracts hold promise in modulating cerebral ischemia-reperfusion injury through counteraction of relevant pathophysiologic processes such as oxidative stress.

Therapeutic potential of natural compounds from Chinese medicine in acute and subacute phases of ischemic stroke

Stroke is one of the leading causes of death and disability in adults worldwide, resulting in huge social and financial burdens. Extracts from herbs, especially those used in Chinese medicine, have emerged as new pharmaceuticals for stroke treatment. Here we review the evidence from preclinical studies investigating neuroprotective properties of Chinese medicinal compounds through their application in acute and subacute phases of ischemic stroke, and highlight potential mechanisms underlying their therapeutic effects. It is noteworthy that many herbal compounds have been shown to target multiple mechanisms and in combinations may exert synergistic effects on signaling pathways, thereby attenuating multiple aspects of ischemic pathology. We conclude the paper with a general discussion of the prospects for novel natural compound-based regimens against stroke.

Effect of Scoparia dulcis on noise stress induced adaptive immunity and cytokine response in immunized Wistar rats

Background

Noise acts as a stressor and is reported to have impact on individual health depending on nature, type, intensity and perception. Modern medicine has no effective drugs or cure to prevent its consequences. Being an environmental stressor noise cannot be avoided; instead minimizing its exposure or consuming anti-stressor and adaptogens from plants can be considered.

Objectives

The present study was carried out to evaluate the anti-stressor, adaptogen and immunostimulatory activity of Scoparia dulcis against noise-induced stress in Wistar rat models.

Material and methods

Noise stress in rats was created by broadband white noise generator, 100 dB A/4 h daily/15 days and S. dulcis (200 mg/kg b.w.) was administered orally. 8 groups of rats were used consisting of 6 animals each; 4 groups for unimmunized and 4 groups for immunized. For immunization, sheep red blood cells (5 × 10⁹ cells/ml) were injected intraperitoneally.

Results

Sub-acute noise exposed rats showed a significant increase in corticosterone and IL-4 levels in both immunized and unimmunized rats whereas lymphocytes, antibody titration, soluble immune complex, IL-4 showed a marked increase with a significant decrease in IL-2, TNF-α, IFN-γ cytokines only in unimmunized rats. Immunized noise exposed rats presented increased leukocyte migration index and decreased foot pad thickness, IL-2, TNF-α, IFN-γ with no changes in the lymphocytes.

Conclusion

S. dulcis (SD) has normalized and prevented the noise induced changes in cell-mediated and humoral immunity and it could be the presence of anti-stressor and immuno stimulant activity of the plant.

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Noise being an environmental stressor, it cannot be avoided. Hence this study reveals the immunotoxic effects of noise.

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We examine the changes in the adaptive immunity after immunization with sheep RBCs along with noise exposure.

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TH1 and TH2 cytokine profiles were examined in the spleen as well as serum to determine the alteration in immune pathways.

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To examine the effect of Scoparia dulcis as an anti stressor (adaptogen) and immunomodulatory property.

Blood-brain barrier alterations provide evidence of subacute diaschisis in an ischemic stroke rat model

BACKGROUND

Comprehensive stroke studies reveal diaschisis, a loss of function due to pathological deficits in brain areas remote from initial ischemic lesion. However, blood-brain barrier (BBB) competence in subacute diaschisis is uncertain. The present study investigated subacute diaschisis in a focal ischemic stroke rat model. Specific focuses were BBB integrity and related pathogenic processes in contralateral brain areas.

METHODOLOGY/PRINCIPAL FINDINGS

In ipsilateral hemisphere 7 days after transient middle cerebral artery occlusion (tMCAO), significant BBB alterations characterized by large Evans Blue (EB) parenchymal extravasation, autophagosome accumulation, increased reactive astrocytes and activated microglia, demyelinization, and neuronal damage were detected in the striatum, motor and somatosensory cortices. Vascular damage identified by ultrastuctural and immunohistochemical analyses also occurred in the contralateral hemisphere. In contralateral striatum and motor cortex, major ultrastructural BBB changes included: swollen and vacuolated endothelial cells containing numerous autophagosomes, pericyte degeneration, and perivascular edema. Additionally, prominent EB extravasation, increased endothelial autophagosome formation, rampant astrogliosis, activated microglia, widespread neuronal pyknosis and decreased myelin were observed in contralateral striatum, and motor and somatosensory cortices.

CONCLUSIONS/SIGNIFICANCE

These results demonstrate focal ischemic stroke-induced pathological disturbances in ipsilateral, as well as in contralateral brain areas, which were shown to be closely associated with BBB breakdown in remote brain microvessels and endothelial autophagosome accumulation. This microvascular damage in subacute phase likely revealed ischemic diaschisis and should be considered in development of treatment strategies for stroke.