Molecular Alterations and Effects of Acute Dehydroepiandrosterone Treatment Following Brief Bilateral Common Carotid Artery Occlusion: Relevance to Transient Ischemic Attack

Sustained Systemic Antioxidative Effects of Intermittent Theta Burst Stimulation beyond Neurodegeneration: Implications in Therapy in 6-Hydroxydopamine Model of Parkinson's Disease

Parkinson's disease (PD) is manifested by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and caudoputamen (Cp), leading to the development of motor and non-motor symptoms. The contribution of oxidative stress to the development and progression of PD is increasingly recognized. Experimental models show that strengthening antioxidant defenses and reducing pro-oxidant status may have beneficial effects on disease progression. In this study, the neuroprotective potential of intermittent theta burst stimulation (iTBS) is investigated in a 6-hydroxydopamine (6-OHDA)-induced PD model in rats seven days after intoxication which corresponds to the occurrence of first motor symptoms. Two-month-old male Wistar rats were unilaterally injected with 6-OHDA to mimic PD pathology and were subsequently divided into two groups to receive either iTBS or sham stimulation for 21 days. The main oxidative parameters were analyzed in the caudoputamen, substantia nigra pars compacta, and serum. iTBS treatment notably mitigated oxidative stress indicators, simultaneously increasing antioxidative parameters in the caudoputamen and substantia nigra pars compacta well after 6-OHDA-induced neurodegeneration process was over. Serum analysis confirmed the systemic effect of iTBS with a decrease in oxidative markers and an increase in antioxidants. Prolonged iTBS exerts a modulatory effect on oxidative/antioxidant parameters in the 6-OHDA-induced PD model, suggesting a potential neuroprotective benefit, even though at this specific time point 6-OHDA-induced oxidative status was unaltered. These results emphasize the need to further explore the mechanisms of iTBS and argue in favor of considering it as a therapeutic intervention in PD and related neurodegenerative diseases.

Ectonucleotidases in the hippocampus: Spatial distribution and expression after ovariectomy and estradiol replacement

Extracellular purine nucleotides, such as adenosine 5'-triphosphate (ATP), are important modulators of hippocampal function and plasticity. In the extracellular space, ATP is inherently short-lived molecule, which undergoes rapid enzymatic degradation to adenosine by ectonucleotidases. Given that ectonucleotidases have distinct and overlapping distribution in the hippocampus, and as ovarian hormones participate in a formation, maturation, and a refinement of synaptic contacts, both during development and in adulthood, the present chapter summarizes known data about spatial distribution of selected ecto-enzymes and estradiol-induced effects on ectonucleotidases in the rat hippocampus.

Comparison of the Effectiveness of Ring-Stripping Retrograde Endarterectomy and Carotid Artery Crossover Bypass in the Treatment of Patients with Symptomatic Riles Type 1A Common Carotid Artery Occlusion

OBJECTIVE

The surgical procedure most appropriate for treating symptomatic Riles type 1A common carotid artery occlusion (CCAO) is unclear. This study compares the effects of ring-stripping retrograde endarterectomy (RSRE) and carotid artery crossover bypass (CACB) on cerebral perfusion improvement in patients with symptomatic Riles type 1A CCAO.

METHODS

We conducted a retrospective analysis of symptomatic Riles type 1A CCAO patients treated at our centre. Postoperative improvements in the ipsilateral internal carotid artery (ICA) flow rate, ipsilateral cerebral blood perfusion (CBP) and the stroke recurrence rate were compared between patients who underwent RSRE and those who underwent CACB.

RESULTS

A total of 20 CCAO patients were surgically treated at our centre from 2011 to 2018. Nine of these patients underwent RSRE, and eleven underwent CACB. No significant differences were identified between the groups in the ipsilateral blood flow rate of the ICA immediately after surgery and the ipsilateral-to-contralateral mean transit time ratios 1 day after surgery. However, the flow rate in the ICA was significantly higher in the RSRE group than in the CACB group 1 year after surgery (135.44 ± 19.22 ml/min vs. 116.36 ± 17.70 ml/min, p = 0.033). For CBP, the ipsilateral-to-contralateral mean transit time ratios were significantly lower in RSRE patients than in CACB patients 1 year after surgery (1.005 ± 0.052 vs. 1.064 ± 0.066, p = 0.044). In addition, the postoperative modified Rankin scale (mRS) score at the latest follow-up point (p = 0.884) and the stroke recurrence rate during the follow-up (88.9% vs. 90.9%, p > 0.999) were not significantly different between the two groups.

CONCLUSIONS

Although the postoperative mRS score and the stroke recurrence rate were not significantly different between RSRE and CACB patients, compared to CACB, RSRE was better for improving the ipsilateral ICA flow rate and cerebral perfusion in symptomatic Riles type 1A CCAO patients.