Serum S-100B Protein as A Biochemical Marker of Brain Injury: A Review of Current Concepts

Abstract

S-100 protein, described initially by Moore, constitutes a large family of at least 20 proteins with calcium binding ability. It is found as homo- or hetero-dimers of two different subunits (A and B). Types S-100AB and S-100BB are described as S-100B protein and are shown to be highly specific for nervous tissue. It is present in the cytosol of glial and Schwann cells, and also in adipocytes and chondrocytes, although in very low concentrations in the latter two. The role of protein S-100B is not yet fully understood. It is suggested that it has intracellular and extracellular neurotropic as well as neurotoxic function. At nanomolar levels, S-100B stimulates neurite outgrowth and enhances survival of neurons. However, at micromolar levels it stimulates the expression of inflammatory cytokines and induces apoptosis. Recently, serum S-100B protein has been proved to be an attractive surrogate marker of primary severe brain injury and secondary insults. It can be measured in the arterial and venous serum; it is not affected by haemolysis and remains stable for several hours without the need for immediate analysis. Its short half-life makes measurements crucial in the emergency and intensive care settings. This review summarises published findings on S-100B regarding its role as a serum biochemical marker of brain injury, i.e., after severe, moderate or mild neuro-trauma, subarachnoid haemorrhage, thrombo-embolic stroke, cerebral ischaemia and brain tumours, as well as extracranial trauma, neurodegenerative and psychiatric disorders.

Effects of Mild Hypothermia Treatment on Rat Hippocampal β-Amyloid Expression Following Traumatic Brain Injury

“…Studies of the pathogenesis of progressive SBI in TBI patients have focused primarily on particular enzymes and structural proteins, including neuron-specific enolase, glial fibrillary acidic protein, and S-100b molecules that directly indicate damage (Korfias et al, 2006). However, the application of modern molecular techniques for the separation and identification of protein degradation products has allowed researchers to identify other TBI-related proteins that have a greater involvement in SBI processes, such as Ab proteins (Korfias et al, 2006).…”

“…However, the application of modern molecular techniques for the separation and identification of protein degradation products has allowed researchers to identify other TBI-related proteins that have a greater involvement in SBI processes, such as Ab proteins (Korfias et al, 2006). Ab expression in the cerebrospinal fluid of TBI patients increases in patients with poor prognoses, potentially indicating axon damage (Lichtlen and Mohajeri, 2008).…”

Prognostic Value of Serum S100 Protein by Elecsys S100 Immunoassay in Patients with Spontaneous Subarachnoid and Intracerebral Hemorrhages

“…It has two subunits of alpha and beta. S100 beta or S100B has been known to be released from the damaged astrocyte in various conditions, such as cerebral infarction, head injury, less frequently spontaneous subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH) and reflect the severity of neuronal damage 5,6,9,11,12,19,22) .…”

The role of hypoxia in stroke and convulsive states. Antihypoxants

“…Кроме того, S100B влияет на импульсную активность нейронов за счет моду-ляции К + -токов: при воздействии белка на нейрон происходит гиперполяризация потенциала покоя и подавляется спонтанная генерация потенциалов действия. S100B используют в качестве диагно-стического маркера при различных заболеваниях, в частности гипоксического повреждения мозга (на-пример, ишемии после инсульта) и болезни Альц-геймера [34,36].…”