Neuroprotective mechanisms of oxygen and ethanol: a potential combination therapy in stroke.

Currently, stroke researchers are racing to develop neuroprotective strategies that shield the brain from ischemia-induced injury. To date, neuroprotective agents that have shown promise in animal studies have failed in clinical trials. Since the pathophysiology of ischemic stroke exploits numerous pathways leading to cellular injury, a combination of neuroprotective agents may offer substantially better results than a single agent alone - by intervening in multiple mechanisms. In this paper, we consider an approach using combination therapy with normobaric oxygen (NBO) and ethanol. Studies indicate that NBO therapy improves tissue oxygenation, thereby reducing the extent of hypoxic injury and decelerating the development of tissue necrosis when administered early after stroke onset. Studies have also demonstrated that low to moderate levels of ethanol not only decrease the risk of stroke, but also reduce post-ischemic sequelae. This article reviews the history of NBO and ethanol therapies, their mechanisms of action, the results of key clinical trials, and the rationale for their use as a combination therapy in the context of stroke treatment.

Hyperglycemia in stroke and possible treatments.

Hyperglycemia affects approximately one-third of acute ischemic stroke patients and is associated with poor clinical outcomes. In experimental and clinical stroke studies, hyperglycemia has been shown to be detrimental to the penumbral tissue for several reasons. First, hyperglycemia exacerbates both calcium imbalance and the accumulation of reactive oxygen species (ROS) in neurons, leading to increased apoptosis. Second, hyperglycemia fuels anaerobic energy production, causing lactic acidosis, which further stresses neurons in the penumbral regions. Third, hyperglycemia decreases blood perfusion after ischemic stroke by lowering the availability of nitric oxide (NO), which is a crucial mediator of vasodilation. Lastly, hyperglycemia intensifies the inflammatory response after stroke, causing edema, and hemorrhage through disruption of the blood brain barrier and degradation of white matter, which leads to a worsening of functional outcomes. Many neuroprotective treatments addressing hyperglycemia in stroke have been implemented in the past decade. Early clinical use of insulin provided mixed results due to insufficiently controlled glucose levels and heterogeneity of patient population. Recently, however, the latest Stroke Hyperglycemia Insulin Network Effort trial has addressed the shortcomings of insulin therapy. While glucagon-like protein-1 administration, hyperbaric oxygen preconditioning, and ethanol therapy appear promising, these treatments remain in their infancy and more research is needed to better understand the mechanisms underlying hyperglycemia-induced injuries. Elucidation of these mechanistic pathways could lead to the development of rational treatments that reduce hyperglycemia-associated injuries and improve functional outcomes for ischemic stroke patients.

Anterior herniation of lumbar disc induces persistent visceral pain: discogenic visceral pain: discogenic visceral pain / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Visceral pain is a common cause for seeking medical attention. Afferent fibers innervating viscera project to the central nervous system via sympathetic nerves. The lumbar sympathetic nerve trunk lies in front of the lumbar spine. Thus, it is possible for patients to suffer visceral pain originating from sympathetic nerve irritation induced by anterior herniation of the lumbar disc. This study aimed to evaluate lumbar discogenic visceral pain and its treatment.</p><p><b>METHODS</b>Twelve consecutive patients with a median age of 56.4 years were enrolled for investigation between June 2012 and December 2012. These patients suffered from long-term abdominal pain unresponsive to current treatment options. Apart from obvious anterior herniation of the lumbar discs and high signal intensity anterior to the herniated disc on magnetic resonance imaging, no significant pathology was noted on gastroscopy, vascular ultrasound, or abdominal computed tomography (CT). To prove that their visceral pain originated from the anteriorly protruding disc, we evaluated whether pain was relieved by sympathetic block at the level of the anteriorly protruding disc. If the block was effective, CT-guided continuous lumbar sympathetic nerve block was finally performed.</p><p><b>RESULTS</b>All patients were positive for pain relief by sympathetic block. Furthermore, the average Visual Analog Scale of visceral pain significantly improved after treatment in all patients (P < 0.05). Up to 11/12 patients had satisfactory pain relief at 1 week after discharge, 8/12 at 4 weeks, 7/12 at 8 weeks, 6/12 at 12 weeks, and 5/12 at 24 weeks.</p><p><b>CONCLUSIONS</b>It is important to consider the possibility of discogenic visceral pain secondary to anterior herniation of the lumbar disc when forming a differential diagnosis for seemingly idiopathic abdominal pain. Continuous lumbar sympathetic nerve block is an effective and safe therapy for patients with discogenic visceral pain.</p>