Search results for "Shock proteins"

A multipronged approach to unveil the emerging role of Hsp60 in chronic obstructive pulmonary disease

2011

Inflammation is a major component of chronic obstructive pulmonary disease (COPD) and its cause and mechanisms are still incompletely understood. For example, the role of heat shock proteins (Hsps), many of which are molecular chaperones, has not been explored in detail in COPD, despite the fact that these molecules are known to participate in inflammation in other diseases. It has been shown that extracellular Hsps can signal certain types of T cells, macrophages, dendritic cells, and neutrophils and, thereby, elicit inflammation and immunity. However, these phenomena have not been investigated in COPD despite: a) the increasing awareness of Hsp participation in inflammation and immunity; …

Heat Shock Proteins in Multiple Sclerosis Pathogenesis: Friend or Foe?

2015

Multiple Sclerosis is a complex chronic inflammatory, neurodegenerative disease conditioned by genetic, epigenetic and environmental factors. Main pathological features of MS include areas of focal demyelination of white matter characterized by gliosis, neuron and oligodendrocyte loss. Neurodegenerative as well as immune-mediated processes play a role in the pathogenesis of this disease. One of these immunogenic factors could be represented by the heat shock proteins. HSP exhibit cytoprotective and cytostimulatory effects due to their molecular chaperones role, in many brain model misfolding diseases such as Alzheimer’s and Parkinson’s diseases, whereas still no unambiguous results have bee…

Study of the effects of Pleurotuseryngii var. eryngii on heat shock proteins and cytokines levels in a mouse model of colon carcinoma

Medicinal mushrooms are wonderful source of nutraceuticals with a wide range of benefit for human health. The current anti-cancer therapy is not always target specific and often is associated with complications for patients. Therefore new effective and less toxic therapeutic approaches are needed. Heat shock proteins (Hsps) are highly expressed in a variety of cancer types contributing to tumor cell propagation. Here, we treated C26 colon cancer cells with a cold-water extracts of an edible mushrooms Pleurotuseryngii var. eryngii (Pleuery). Hsp90, 70, 60 and 27 levels were measured by western blotting and immunofluorescence analysis. Moreover, we evaluated Pleueryanti cancer effect in an an…

Comparative analysis of the coordinated motion of Hsp70s from different organelles observed by single-molecule three-color FRET.

2021

Cellular function depends on the correct folding of proteins inside the cell. Heat-shock proteins 70 (Hsp70s), being among the first molecular chaperones binding to nascently translated proteins, aid in protein folding and transport. They undergo large, coordinated intra- and interdomain structural rearrangements mediated by allosteric interactions. Here, we applied a three-color single-molecule Forster resonance energy transfer (FRET) combined with three-color photon distribution analysis to compare the conformational cycle of the Hsp70 chaperones DnaK, Ssc1, and BiP. By capturing three distances simultaneously, we can identify coordinated structural changes during the functional cycle. Be…

Extracellular heat shock proteins in cancer: From early diagnosis to new therapeutic approach

2021

In cancer, human cells lose the ability to properly control the series of events that occur constantly during cell growth and division, including protein expression, stability, and dynamics. Heat shock proteins (Hsps) are key molecules in these events, constitutively expressed at high levels and could furthermore be induced by the response to cancer-induced stress. In tumor cells, Hsps have been shown to be implicated in the regulation of apoptosis, immune responses, angiogenesis and metastasis; in some cases, they can be overexpressed and dysregulated, representing important cancer hallmarks. In the past few years, it has been demonstrated that Hsps can be released by tumor cells through s…

Inhibition of HSP27 blocks fibrosis development and EMT features by promoting Snail degradation

2013

Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by myofibroblast proliferation. Transition of epithelial/mesothelial cells into myofibroblasts [epithelial-to-mesenchymal transition (EMT)] occurs under the influence of transforming growth factor (TGF)-β1, with Snail being a major transcription factor. We study here the role of the heat-shock protein HSP27 in fibrogenesis and EMT. In vitro, we have up- and down-modulated HSP27 expression in mesothelial and epithelial cell lines and studied the expression of different EMT markers induced by TGF-β1. In vivo, we inhibited HSP27 with the antisense oligonucleotide OGX-427 (in phase II clinical trials as anticancer agent)…

Elevated cortisol modulates hsp70 and hsp90 gene expression and protein in sea bass head kidney and isolated leukocytes

2012

In fish, interactions between Hsps and cortisol are involved in stress modulated physiological processes including innate immune responses. Cortisol exerts a role in the regulation of Hsps synthesis. Fish head kidney is a lymphomieloid and endocrine organ releasing cortisol, and it is the central organ for immune-endocrine interactions. In sea bass, cortisol intraperitoneal injection and in vitro treatment of head kidney cells show that inducible Hsp70 and Hsp90 are modulated by this hormone. However, an inverse relationship between mRNA expression (real-time PCR) and Hsp70 and Hsp90 protein levels (densitometric band analysis) was found. Time-course assays indicate a cortisol-mediated regu…

Human Enterovirus Group B Viruses Rely on Vimentin Dynamics for Efficient Processing of Viral Nonstructural Proteins.

2019

A virus needs the host cell in order to replicate and produce new progeny viruses. For this, the virus takes over the host cell and modifies it to become a factory for viral proteins. Irrespective of the specific virus family, these proteins can be divided into structural and nonstructural proteins. Structural proteins are the building blocks for the new progeny virions, whereas the nonstructural proteins orchestrate the takeover of the host cell and its functions. Here, we have shown a mechanism that viruses exploit in order to regulate the host cell. We show that viral protein synthesis induces vimentin cages, which promote production of specific viral proteins that eventually control apo…

Induction of Hsp70 by the Herbicide Oxyfluorfen (Goal) in the Egyptian Nile Fish, Oreochromis niloticus

1999

This paper deals with the expression of the biomarker hsp70 in the liver and kidney of the freshwater fish Oreochromis niloticus following exposure to the herbicide oxyfluorfen (Goal). Fishes were exposed to three concentrations, the 96-h LC50 (3 mg/L), the 96-h (1/2)LC50 (1.5 mg/L), and the 96-h (1/4)LC50 (0.75 mg/L) of oxyfluorfen for 6, 15, and 24 days, respectively, and samples were taken at three different time periods for each concentration. The livers responded to the herbicide by an induction of the expression of both the constitutive (hsp75; Mr 75 kDa) and the inducible (hsp73; Mr 73 kDa) hsp70 proteins. In kidney, the herbicide induced a time-dependent increase in the expression o…

Antibodies to alpha B-crystallin, vimentin, and heat shock protein 70 in aqueous humor of patients with normal tension glaucoma and IgG antibody patt…

2007

To show the existence of IgG antibodies against retinal antigens in aqueous humor of normal tension glaucoma patients.Forty-two patients were included in this study. Aqueous humor was collected from control subjects (CO; n = 21) and patients with normal tension glaucoma (NTG; n = 21). Western blot methods against bovine retinal antigens were used to detect the IgG antibody patterns. The complex antibody repertoires were analyzed by multivariate statistical techniques. Mass spectrometry was used to identify the most important antigens.Very complex IgG antibody patterns against retinal antigens were found in all analyzed aqueous humor samples. Our multivariate approach could quantify differen…