Physiological Sympathetic Activation Reduces Systemic Inflammation: Role of Baroreflex and Chemoreflex

Baroreflex and chemoreflex act through the autonomic nervous system, which is involved with the neural regulation of inflammation. The present study reports the effects of reflex physiological sympathetic activation in endotoxemic rats using bilateral carotid occlusion (BCO), a physiological approach involving the baroreflex and chemoreflex mechanisms and the influence of the baroreceptors and peripheral chemoreceptors in the cardiovascular and systemic inflammatory responses. After lipopolysaccharide (LPS) administration, the arterial pressure was recorded during 360 min in unanesthetized rats, and serial blood samples were collected to analyze the plasma cytokine levels. BCO elicited the reflex activation of the sympathetic nervous system, providing the following outcomes: (I) increased the power of the low-frequency band in the spectrum of the systolic arterial pressure during the BCO period; (II) reduced the levels of pro-inflammatory cytokines in plasma, including the tumor necrosis factor (TNF) and the interleukin (IL)-1β; (III) increased the plasma levels of anti-inflammatory cytokine IL-10, 90 min after LPS administration. Moreover, selective baroreceptor or chemoreceptor denervation deactivated mechanosensitive and chemical sensors, respectively, and decreased the release of the LPS-induced cytokine but did not alter the BCO modulatory effects. These results show, for the first time, that physiological reflex activation of the sympathetic circuit decreases the inflammatory response in endotoxemic rats and suggest a novel function for the baroreceptors as immunosensors during the systemic inflammation.

Unusual presentation of moyamoya disease with popliteal involvement: case report and review of the literature

Moyamoya disease is a rare disorder that involves the cerebrovascular system. Usually, it leads to occlusion of the arteries of the cerebral system and causes cerebral circulatory complaints. A 48-year-old female patient was admitted to our clinic with intermittent claudication in both legs. Biphasic and monophasic waveform patterns were detected bilaterally in distal (trifurcation arteries) lower extremities with Doppler sonography. The patient therefore underwent systemic vascular examination. Computed tomography angiography revealed bilateral carotid occlusion at the level of supraclinoid segments, and opacifications were detected at the distal segments of the bilateral anterior cerebellar and middle cerebellar arteries. The patient was diagnosed with moyamoya disease, and anticoagulant treatment was started. In conclusion, most previous reports have presented the cerebrovascular involvement of moyamoya disease. However, this disease can involve different peripheral vascular systems and careful and systemic vascular examination is necessary for an exact diagnosis.

Facing the crossroads: acute stroke with bilateral carotid occlusion

We present a previously unreported case of endovascular therapy in the acute setting of ischaemic stroke in a patient with bilateral carotid occlusion (BCO). A 54-year-old man presents with sudden onset of right-sided weakness, difficulty speaking and left-sided gaze, with National Institute of Health Stroke Scale of 22 and no abnormalities on plain CT head. CT angiography showed BCO and CT perfusion demonstrated extensive area of penumbra in both hemispheres. The patient was sent for cerebral angiography that confirmed BCO. Since symptomatology was a left middle cerebral arteries syndrome, decision was made to angioplasty and stent the left internal carotid artery emergently, which was performed successfully and the patient had complete resolution of symptoms. Acute stroke with BCO represents a challenge in decision making regarding acute management and individual assessment must be made.

Controlled arterial reflow after ischemia induces better outcomes in the juvenile rat brain

Our objective was to determine whether controlled reflow on one side and/or the other side after bilateral carotid occlusion release could reduce cell death in focal ischemic P14 rats. Arterial blood flow was measured using ultrasonography. Cell death, inflammation and nitrotyrosine were measured using immunofluorescence. When reflow was first induced in the contralateral side, we observed improved outcome markers compared with those when reflow was first induced in the ipsilateral side and/or simultaneous reflow was induced in both sides. Our data suggest that progressive rerouting of arterial flow through the circle of Willis toward the ischemic site reduced cell death.

Cyclo-prolylalanine: the neuroprotective and antioxidative properties on the model of acute cerebral disease in rats

The neuroprotective and antioxidative properties of the new neuroactive peptide cyclo-prolylalanine (DKP-9) were studied on the model of acute cerebral disease (ACD, irreversible bilateral carotid occlusion) in rats. Under the conditions of intranasal administration in the therapeutic mode at the doses 0.02 mg/kg or 0.1 mg/kg peptide DKP-9 has increased rats’ survival rate to 40% or 70% respectively. Increase of the DKP-9 dose to 1 mg/kg reduced the protective effect of it. Peptide DKP-9 has effective decreased the neurological and cognitive deficits in acute period of ACD (4 days) exceeding the reference drug semax (0.1 mg/kg, intranasally in same treatment mode). Under the conditions of open-field test the sedative properties of DKP-9 and also the ability of it to reduce rats’ stress-induced anxious reactions were established. Antioxidative properties of DKP-9 are followed by increase of the reduced glutathione level, normalize of the catalase activity, decrease of the level of lipid peroxidation products as well as increase of the brain neurons’ energy metabolism. The further investigation of mechanism of cyclo-prolylalanine (DKP-9) action on the pathogenic links of ischemic cascade is perspective.