Stroke and Cerebrovascular Disease

Keywords Atherosclerosis Complement Hemorrhagic stroke Ischemic stroke Stroke 

As has been outlined in prior chapters, the immune system is responsible for host responses to infection, and responds in the same way to tissue injury occurring in the body, e.g., as 

These changing concepts of the role of the immune system and inflammation in stroke and cerebrovascular disease have led to searches for new treatment and prevention strategies. This chapter will review the current state of knowledge about inflammation and the immune system in stroke and atherosclerosis and discuss potential therapeutic strategies. 

Under physiological conditions there is a small resident population of macrophages—microglia and perivascular macrophages—along with some roaming T cell lymphocytes in the central nervous system. However, most of the immune cells involved in inflammation after stroke are in fact derived from the systemic circulation. 

However as stated above, there are some resident immune cells in the brain these include the microglia, which are derived from the mesoderm and can be replenished from the bone marrow (in contrast to neurons and astrocytes which are ectoderm derived and only replenished in minute numbers). Unlike other tissue macrophages, microglia do not express MHC antigens until they become activated. Another resident 

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Strachan DP, Carrington D, Mendall MA et al. (1999). Relation of Chlamydia pneumoniae serology to mortality and incidence of ischemic heart disease over 13 years in the Caerphilly Prospective Heart Disease Study. British Medical Journal 318 1035-1039 Stroke Prevention in Atrial Fibrillation Investigators (1992). Predictors of thromboembolism in atrial fibrillation II Echocardiographic features of patients at risk. Annals of Internal Medicine 116 6-12 Stroke Prevention in Atrial Fibrillation Investigators (1995). Risk factors for thromboembolism during aspirin therapy in patients with atrial fibrillation the Stroke Prevention in Atrial Fibrillation Study. Journal of Stroke and Cerebrovascular Disease 5 147-157... 

Leira R, Davalos A, Silva Y, Gil-Peralta A, Tejada J, GarciaM, Castillo J Stroke Project, Cerebrovascular Diseases Group of the Spanish Neurological Society. Early neurological deterioration in intracerebral hemorrhage Predictors and associated factors. Neurology 2004 63(3) 461 67. 

A 38-year-old man with a family history of cardiovascular and cerebrovascular disease makes an appointment for a routine physical examination with a physician he has not seen before. He explains that his father died young of a heart attack and that two paternal uncles have suffered strokes in their late 40s. Physical examination reveals yellowish lumps on his eyelids (xanthelasmas, which are often associated with a lipid disorder) and a resting blood pressure of 186/95 mm Hg. There is some excess visceral fat, and his body mass index calculates to 26.5. Total serum cholesterol (476 mg/dL) and triglycerides (288 mg/dL) are elevated and subsequent angiography reveals atherosclerotic restrictions of at least two coronary arteries. 

Brott T. and Hacke W. (1998) General treatment of acute ischemic stroke. In Cerebrovascular Disease Pathophysiology, Diagnosis and Management (Ginsberg M. D. and Bogousslavsky J., eds.), Blackwell Science, Malden, pp. 1864— 1878. 

Many stroke patients have atherosclerosis, indicating a link between cardiac and cerebrovascular disease (see Table 2.2). But it is difficult for clinicians to predict the likelihood of stroke using signs and symptoms of heart disease. For instance, carotid bruits are more reliably predictive of ischemic heart disease than of stroke. Around 23% of ischemic stroke originates from carotid atherosclerosis. The degree of stenosis alone cannot predict vulnerable lesions [12]. Cerebrovascular ischemic events also result from low-grade carotid stenosis. 

The cardiovascular disease and cerebrovascular disease can lead to cerebral ischemia. Cerebral ischemia initiates a number of processes which can lead to progressive brain damage (Brott Bogousslavsky, 2000). Cerebral ischemia can lead to activation of free radicals, NMDA and apoptosis, in the brain, all potential mechanisms of brain damage in patients with hypoperfusion or stroke (Vexler et al., 1997). Anoxic injury to brain endothelial cells can increase production of NO, which can lead to free radical formation (Kumar et al., 1996). Apoptosis, or programed cell death, is another mode of destruction of brain cells in stroke (Vexler... 

In summary, the steadily increasing size of geriatric populations in developed countries and the resultant increases in age-related diseases of the brain have provided the impetus for intensive study of the processes underlying neurodegeneration. A better understanding of these processes will likely lead to better methods of treatment not only for progressive memory disorders such as Alzheimer disease, but also for motor disorders such as amyotrophic lateral sclerosis, and cerebrovascular disorders such as stroke. 

Diabetes mellitus is a complicated, chronic disorder characterized by either insufficient insulin production by the beta cells of die pancreas or by cellular resistance to insulin. Insulin insufficiency results in elevated blood glucose levels, or hyperglycemia As a result of the disease, individuals with diabetes are at greater risk for a number of disorders, including myocardial infarction, cerebrovascular accident (stroke), blindness, kidney disease, and lower limb amputations. 

Mohr JP, Sacco RL. Morbidity and mortality of stroke. In Moore, WS editor. Surgery for cerebrovascular disease. W.B. Saunders Company, 1996 p 9-15. 

Neurodegeneration Localised or widespread death of neurons, a feature of a number of brain disorders, such as Alzheimer s disease, Parkinson s disease and cerebrovascular stroke. It can also be caused by neurotoxic drugs like MDMA/Ecstasy, although there is debate over whether this occurs in humans as well as laboratory animals. 

J7. Gurgens, G., and Kdltringer, P., Lipoprotein(a) in ischemic cerebrovascular disease A new approach to the assessment of risk of stroke. Neurology 37, 513-515 (1987). 

Cardiovascular disease Any abnormal condition characterized by dysfunction of the heart and blood vessels. CVD includes atherosclerosis (especially coronary heart disease, which can lead to heart attacks), cerebrovascular disease (e.g., stroke), and hypertension (high blood pressure). [NIH]... 

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