Proteomic profiling of heat acclimation in cerebrospinal fluid of rabbit.

UNLABELLED: Heat acclimation (AC) is a phenotypic adaptation to the high ambient temperatures. So far, the physiological effects of AC have been well studied, but the molecular mechanisms underlying it, especially the proteomic studies have been rarely reported. Conducting a protein profile of cerebrospinal fluid (CSF) can facilitate the understanding of molecular pathways involved in AC and identifying stress-specific proteins as a laboratory biomarker. In this study we carried out proteomic profiling of the AC in CSF of rabbit, which would allow a deep insight into molecular signals underlying the AC. For this purpose, rabbits were subjected to AC (dry bulb temperature of (36±1)°C, wet bulb temperature of (29±0.5)°C, black-bulb temperature of (40±1.0)°C, 100min per day for 21days, untreated rabbits were used as controls. We adopted a gel-free proteomic approach (iTRAQ) method to identify protein composition in CSF of rabbits with AC. In total, 1310 proteins were identified. Among which 127 were significant up-regulated and 77 were down-regulated. According to the functions, all AC-induced proteins were classified into 8 categories, including plasma protein factors, metabolism-related proteins, energy metabolism-related proteins, cell surface/intercellular matrix proteins, stress related proteins, tumor-related proteins, as well as housekeeping proteins and putative proteins. Meanwhile, a total of 21 pathways were found involved in the developing of AC. Further analysis indicated that proteins mostly close to AC were grouped into two signal pathways, the immune-related signal pathways and the carbohydrate/lipoprotein metabolism-related signal pathways. Our study was first to carry out the whole proteomic picture of AC, and screen out the critical signaling pathways involved in this physical procedure. BIOLOGICAL SIGNIFICANCE: This study reported the comparative proteomic analysis of cerebrospinal fluid of rabbits between heat acclimation and normal conditions using the gel-free proteomic mass-spectrometry approach with isotope-labeled samples (iTRAQ) techniques. Mass spectrometry analysis of the proteins from heat acclimated rabbits resulted in the identification of a total of 1310 proteins, among these, 204 proteins were related to the formation of heat acclimation. These proteins were assigned to 8 categories according to their functions. Additionally, 21 pathways involved in infectious diseases, metabolism, immunology, blood circulation, transcriptional regulation and renin-angiotensin were identified by pathway analysis in heat acclimation. This study was the first to use rabbits as a model for unraveling the molecular pathways underlying the establishment of integrative heat acclimation.

Evaluation of host Hsp(s) as potential biomarkers for the diagnosis of tuberculous meningitis.

OBJECTIVES: Diagnosis of tuberculosis meningitis (TBM) remains challenging in tuberculosis (TB) endemic countries. The need for TB biomarkers arises, in part, from the difficulty of accurately diagnosing TBM with the available methods. PATIENTS AND METHODS: To explore the potential of host Hsps (Hsp 25, Hsp 60, Hsp 70 and Hsp 90) as an alternative marker in TBM diagnosis, we evaluated cerebrospinal fluid (CSF) sample of TBM (n=49), Pyogenic Meningitis (PM) (n=20), Viral Meningitis (VM) (n=09), Fungal Meningitis (FM) (n=04) and non infectious control (n=79) patients using indirect ELISA. RESULTS: Out of four Hsps, Hsp 70 and Hsp 90 yields 89% & 88% sensitivity and 82% & 89% specificity, respectively. The positive (PPV) and negative (NPV) predictive values yielded in TBM group for Hsp 70 was 86.27% (73.74-94.27) and 93.51% (85.48-97.83), respectively. For Hsp 90 the obtained PPV was 89.36% (76.88-96.41) and NPV was 91.36% (82.99-96.44). In 86% of TBM patients all the four Hsps were found to be positive and none of the patient was found to be negative for all Hsps in the same group. CONCLUSIONS: The data presented in the study indicate that host Hsp 70 and Hsp 90 shows good sensitivity and specificity and have potential in the diagnosis of TBM disease. The combined use of all Hsps (Hsp 25, Hsp 60, Hsp 70 and Hsp 90) effectively distinguishes patients with TBM from other disease controls.

Redox regulation of cellular stress response in multiple sclerosis.

Multiple sclerosis (MS) is an autoimmune-mediated neurodegenerative disease with characteristic foci of inflammatory demyelination in the brain, spinal cord, and optic nerves. Recent studies have demonstrated not only that axonal damage and neuronal loss are significant pathologic components of MS, but that this neuronal damage is thought to cause the permanent neurologic disability often seen in MS patients. Emerging finding suggests that altered redox homeostasis and increased oxidative stress, primarily implicated in the pathogenesis of MS, are a trigger for activation of a brain stress response. Relevant to maintenance of redox homeostasis, integrated mechanisms controlled by vitagenes operate in brain in preserving neuronal survival during stressful conditions. Vitagenes encode for heat shock proteins (Hsp) Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. In the present study we assess stress response mechanisms in the CSF, plasma and lymphocytes of control patients compared to MS patients. We found that the levels of vitagenes Hsp72, Hsc70, HO-1, as well as oxidative stress markers carbonyls and hydroxynonenals were significantly higher in the blood and CSF of MS patients than in control patients. In addition, an increased expression of Trx and sirtuin 1, together with a decrease in the expression of TrxR were observed. Our data strongly support a pivotal role for redox homeostasis disruption in the pathogenesis of MS and, consistently with the notion that new therapies that prevent neurodegeneration through nonimmunomodulatory mechanisms can have a tremendous potential to work synergistically with current MS therapies, unravel important targets for new cytoprotective strategies.

Heat shock proteins as biomarkers for the rapid detection of brain and spinal cord ischemia: a review and comparison to other methods of detection in thoracic aneurysm repair.

The heat shock proteins (HSPs) are members of highly conserved families of molecular chaperones that have multiple roles in vivo. We discuss the HSPs in general, and Hsp70 and Hsp27 in particular, and their rapid induction by severe stress in the context of tissue and organ expression in physiology and disease. We describe the current state of knowledge of the relationship and interactions between extra- and intracellular HSPs and describe mechanisms and significance of extracellular expression of HSPs. We focus on the role of the heat shock proteins as biomarkers of central nervous system (CNS) ischemia and other severe stressors and discuss recent and novel technologies for rapid measurement of proteins in vivo and ex vivo. The HSPs are compared to other proposed small molecule biomarkers for detection of CNS injury and to other methods of detecting brain and spinal cord ischemia in real time. While other biomarkers may be of use in prognosis and in design of appropriate therapies, none appears to be as rapid as the HSPs; therefore, no other measurement appears to be of use in the immediate detection of ongoing severe ischemia with the intention to immediately intervene to reduce the severity or risk of permanent damage.

Reduction of PrP(C) in human cerebrospinal fluid after spinal cord injury.

It has been estimated that cerebrospinal fluid (CSF) contains approximately 80 proteins that significantly increase or decrease in response to various clinical conditions. Here we have evaluated the CSF protein PrP(C) (cellular prion protein) for possible increases or decreases following spinal cord injury. The physiological function of PrP(C) is not yet completely understood; however, recent findings suggest that PrP(C) may have neuroprotective properties. Our results show that CSF PrP(C) is decreased in spinal cord injured patients 12 h following injury and is absent at 7 days. Given that normal PrP(C) has been proposed to be neuroprotective we speculate that the decrease in CSF PrP(C) levels may influence neuronal cell survival following spinal cord injury.

Autoantibodies against HSP70 family proteins were detected in the cerebrospinal fluid from patients with multiple sclerosis.

We evaluated the specific IgG antibodies against heat shock proteins (HSPs) in cerebrospinal fluids (CSF) from patients with multiple sclerosis (MS). ELISA was employed to examine IgG antibodies against ten HSPs (HSP27, alphaA and alphaB crystallins, HSP60, CCT, Mycobacterium bovis HSP65, Escherichia coli GroEL, HSP70, HSC70 and HSP90) in CSF from 30 patients with MS, and 25 patients with motor neuron diseases (MND). Significantly higher antibody titers against HSP70 and HSC70 proteins were found in CSF obtained from patients with MS as compared with MND independent of CSF total protein, IgG concentrations and IgG indices, respectively. The antibody titers against HSP70 were indicated to be significantly higher in the progressive cases than in cases of remission. The results suggest that IgG antibodies against specific types of HSPs especially HSP70 family proteins (HSP70 and HSC70) in CSF may play an important role in the pathophysiology of MS through the modification of immune response and cytoprotective functions of molecular chaperons.

In cerebrospinal fluid ER chaperones ERp57 and calreticulin bind beta-amyloid.

The beta-amyloids (abetas) are the major components of the plaque observed in the brains of patients with Alzheimer's disease. The conundrum is that although they are produced in everyone during the posttranslational processing in the endoplasmic reticulum (ER) of the amyloid precursor protein (APP), deposits are only observed in the elderly. Our work suggests that normals have a carrier protein(s) keeping them in solution. Based on immunoblotting studies of cerebrospinal fluid (CSF) from normals, we find that the bulk of the abetas are bound to the ER chaperones, ERp57 and calreticulin, suggesting that these may be carrier proteins which prevent aggregation of the abetas and that the deposits are due to faulty ER posttranslational processing of APP with the failure to form this complex. If membrane protein synthesis is similarly affected, it could explain the neuronal dysfunction characteristic of Alzheimer's disease.

Prevalence of anti-heat shock protein antibodies in cerebrospinal fluids of patients with Guillain-Barré syndrome.

We examined antibodies against 10 heat shock proteins (HSPs) in cerebrospinal fluids (CSF) and sera from patients with Guillain-Barré syndrome (GBS). Significantly higher IgG antibody titers against HSP27, HSP60, HSP70 and HSP90 family, including mycobacterial HSP65 and Escherichia coli GroEL, were found in CSF from GBS patients as compared with motor neuron disease. Serum IgG antibodies against each HSP showed no difference between GBS patients and normal controls. GBS seems to be induced by reactive autoimmune responses frequently triggered by infections. The CSF antibodies against HSPs may modify the immune responses and/or cell-protective functions of HSPs in the pathophysiology of GBS.

MR imaging and 1H-MR spectroscopy in a case of juvenile Alexander disease.

The serial MR image and MR spectroscopy in the brain were examined in a young male diagnosed as having juvenile Alexander disease. He had megalencephaly, psychomotor retardation, seizures, and increasing elevation of increasing alpha-B crystallin and heat shock protein 27 in the cerebrospinal fluid. Serial MR images demonstrated increased demyelination of the bilateral frontal region to left occipital region over several years. The myo-inositol/creatine ratio was significantly increased in both the demyelinated white matter and normal area in the MR spectroscopy. These results suggested that demyelination very slowly progressed from the frontal to occipital region and that glial degeneration may occur even in the unaffected white matter of patients with juvenile Alexander disease.