Current perspectives on potential role of albumin in neuroprotection

Abstract

Albumin is the most abundant plasma protein synthesised mainly in the liver. It is also a major component of extracellular fluids including cerebrospinal fluid, interstitial fluid and lymph. Albumin has several biochemical properties including regulation of colloid osmotic pressure of plasma, transportation of hormones, fatty acids, drugs and metabolites across plasma, regulation of microvascular permeability, antioxidant activity, anti-thrombotic activity and anti-inflammatory activity. This multifunctional protein has been implicated in many neurological diseases owing to its ability to regulate hemodynamic properties of the brain circulation as well as the direct neuroprotective actions on neuronal and glial cells. In this review, we summarise various neuroprotective actions of the albumin in the brain. In experimental ischemic stroke, exogenous human serum albumin administration has been found to be neuroprotective via reducing brain swelling, prevention of post-ischemic thrombosis, anti-oxidant activity, hemodilution and increasing the perfusion to the ischemic tissue. Also, human serum albumin administration is currently under clinical trials for treatment of cerebral ischemia. In the experimental models of Alzheimer's disease, albumin has been implicated in neuroprotection by inhibiting polymerisation and enhancing the clearance of amyloid β. The direct neuroprotective actions on neuronal and glial cells are mediated via endogenously produced albumin or cellular uptake of blood derived albumin. These neuroprotective effects of albumin are partly attributed to anti-oxidant property and modulation of intracellular signalling of neuronal or glial cells. The recent finding of de novo synthesis of albumin in microglial cells directs us to explore newer roles of this endogenously produced multifunctional protein in normal as well as pathological conditions of the brain.

Serum Albumin Levels in Relation to Tumor Parameters in Hepatocellular Carcinoma Patients

“…Albumin also has a variety of well-studied effects, in addition to regulation of plasma colloid osmotic pressure. These include transportation of hormones, fatty acids and drugs, and also antiinflammatory, antioxidant activity and protection against ischemic damage (34)(35)(36)(37)(38)(39)(40)(41)(42), and it may even be involved in TGFβ-mediated growth control (43). Low albumin is associated with enhanced inflammation, whereas albumin therapy in cirrhotic patients can suppress hepatic inflammation (44,45).…”

Haemodilution for acute ischaemic stroke

“…Non-systematic reviews of acute ischaemic stroke therapies including neuroprotection (Ginsberg 2008) and albumin (Prajapati 2011) have been published. Ginsberg 2008 discusses haemodilution trials referenced in this review.…”

Human serum albumin: From bench to bedside

“…The HSA concentration in the plasma is about 7 Â 10 À4 M and the intravascular mass is about 120 g. HSA circulates from the blood across the capillary wall into the interstitial compartments, including cerebrospinal fluid, and returns to the blood through the lymphatic system with a circulation half-life of approximately 16 hours. The movement of HSA across the capillary wall is defined as the transcapillary escape rate (5% per hour), which indicates the percentage of intravascular HSA leaving the intravascular compartment per hour (Peters, 1996;Margarson and Soni, 1998;Evans, 2002;Mendez et al, 2005a;Prajapati et al, 2011).…”

“…In the experimental models of Alzheimer's disease, HSA has been implicated in neuroprotection by inhibiting polymerisation and enhancing the clearance of b-amyloid. These neuroprotective effects of HSA are partly attributed to its anti-oxidant properties and to the modulation of intracellular signaling of neuronal or glial cells (Prajapati et al, 2011).…”