Hypoxia Inducible Factor-1a (HIF-1a) and Heat Shock Proteins 90, 70 (HSP 90, 70) expression in ocular pterygium and normal conjunctiva.

Background - Uncontrolled atrial fibrillation (AF) results in complex changes in the cardiomyocyte electrical and contractile functioning that promote atrial remodeling and the continuation of AF. Recently there has been a growing interest in understanding the role of heat shock proteins (HSPs), which are cytoprotective molecular chaperones, in the pathophysiology of AF. Several groups have examined HSP expression in patients with AF but have yielded mixed results. To allow for better consistency and reproducibility between subjects, we utilized canine models to reproduce AF- promoting conditions to better investigate the role of HSPs in the pathophysiology of AF. Methods - AF promoting conditions were simulated in canine models with fifteen adult mongrel dogs (20.6 to 36.0 kg) divided into three groups: (1) Control (n=5), (2) two week ventricular tachypacing (VTP) induced congestive heart failure (CHF) (n=5), and (3) one week atrial tachypacying (ATP) (n=5). Quick frozen right atrial free wall tissue samples were used for protein isolation and were analyzed via Western blotting with data was expressed as a relative ratio and were analyzed using a two-tailed, unpaired t- test and significance was set at p < 0.05. The expression levels of HSP 90, 70, and 25 were studied along with the phosphorylation status of HSP27 at serine-78. Results - We first examined the effects of the ATP and CHF heart models on the expression of a select group of HSPs via Western Blot. We found that there was no significant difference in levels of expression of HSP 90, 70, or 25 when either ATP or CHF models were compared to control canines. The phosphorylation status of HSP27 was significantly decreased in the CHF canine model when compared to control (p < 0.0111) and it tended towards a decrease in the ATP canine model when compared to control (p=0.0923). Conclusion - This study showed that even though the expression levels of HSPs may remain constant, there are protein phosphorylation and dephosphorylation events that occur in AF that may have important consequences in its pathophysiology. It is therefore necessary to investigate the full scale of HSP modifications during AF and AF-promoting conditions.

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Heat Shock Response in the Thermophilic Enteric Yeast Arxiozyma telluris

Applied and Environmental Microbiology ◽

10.1128/aem.64.8.3063-3065.1998 ◽

1998 ◽

Vol 64 (8) ◽

pp. 3063-3065 ◽

Cited By ~ 3

Author(s):

Michelle L. Deegenaars ◽

Kenneth Watson

Keyword(s):

Heat Stress ◽

Heat Shock ◽

Heat Shock Proteins ◽

Heat Shock Response ◽

Ecological Niche ◽

Hsp 70 ◽

Shock Response ◽

Heat Stress Tolerance ◽

Shock Proteins ◽

Hsp 90

ABSTRACT Heat stress tolerance was examined in the thermophilic enteric yeast Arxiozyma telluris. Heat shock acquisition of thermotolerance and synthesis of heat shock proteins hsp 104, hsp 90, hsp 70, and hsp 60 were induced by a mild heat shock at temperatures from 35 to 40°C for 30 min. The results demonstrate that a yeast which occupies a specialized ecological niche exhibits a typical heat shock response.

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Pemodelan Farmakofor untuk Identifikasi Inhibitor Heat Shock Proteins-90 (HSP-90)

Jurnal Farmasi Galenika (Galenika Journal of Pharmacy) ◽

10.22487/j24428744..v.i.15036 ◽

2020 ◽

Author(s):

Muhammad Arba

Keyword(s):

Hydrogen Bond ◽

Molecular Docking ◽

Heat Shock ◽

Binding Energy ◽

Heat Shock Proteins ◽

Cancer Cells ◽

Operating Characteristics ◽

Hydrogen Bond Donor ◽

Shock Proteins ◽

Hsp 90

Heat shock proteins-90 (HSP-90) is a protein that plays an important role in the life cycle of normal and cancer cells for their self protection from thermal stress, oxidative damage, and cell hypoxia. Inhibition of HSP90 is one way to suppress the growth of cancer cells. In this study, pharmacophore modeling and molecular docking were conducted to identify hit compounds as inhibitors of HSP-90. The pharmacophore feature consists of three hydrogen bond acceptors, one hydrogen bond donor and one hydrophobic feature with Area Under Curve of Receiver Operating Characteristics (AUC-ROC) is 0.5 and the Goodness of Hit (GH) value is 0.752. Screening in the ZINC database generated 1,500 hit compounds, were subjected to molecular docking to determine their binding energy and interactions with HSP-90. The range of binding energy (E) of all hit compounds is -5.68 to -12.24 kcal/mol and there are four best hit compounds namely lig_543, lig_527, lig_1337 and lig_337, when compared to native ligands (PU2, E=-8.25 kkal/mol) based on the binding energy and orientation, which indicate their potential as new HSP-90 inhibitors.

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Pemodelan Farmakofor untuk Identifikasi Inhibitor Heat Shock Proteins-90 (HSP-90)

Jurnal Farmasi Galenika (Galenika Journal of Pharmacy) ◽

10.22487/j24428744.2020.v6.i2.15036 ◽

2020 ◽

Vol 6 (2) ◽

Author(s):

Muhammad Arba ◽

Arfan ◽

Ayu Trisnawati ◽

Desi Kurniawati

Keyword(s):

Hydrogen Bond ◽

Molecular Docking ◽

Heat Shock ◽

Binding Energy ◽

Heat Shock Proteins ◽

Cancer Cells ◽

Operating Characteristics ◽

Hydrogen Bond Donor ◽

Shock Proteins ◽

Hsp 90

Heat shock proteins-90 (HSP-90) is a protein that plays an important role in the life cycle of normal and cancer cells for their self protection from thermal stress, oxidative damage, and cell hypoxia. Inhibition of HSP90 is one way to suppress the growth of cancer cells. In this study, pharmacophore modeling and molecular docking were conducted to identify hit compounds as inhibitors of HSP-90. The pharmacophore feature consists of three hydrogen bond acceptors, one hydrogen bond donor and one hydrophobic feature with Area Under Curve of Receiver Operating Characteristics (AUCROC) is 0.5 and the Goodness of Hit (GH) value is 0.752. Screening in the ZINC database generated 1,500 hit compounds, were subjected to molecular docking to determine their binding energy and interactions with HSP-90. The range of binding energy (E) of all hit compounds is -5.68 to -12.24 kcal/mol and there are four best hit compounds namely lig_543, lig_527, lig_1337 and lig_337, when compared to native ligands (PU2, E=-8.25 kkal/mol) based on the binding energy and orientation, which indicate their potential as new HSP-90 inhibitors.

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Synthesis of heat-shock proteins HSP-70 and HSP-90 in flowers of common buckwheat (Fagopyrum esculentum) under thermal stress

Crop and Pasture Science ◽

10.1071/cp20011 ◽

2020 ◽

Vol 71 (8) ◽

pp. 760 ◽

Cited By ~ 2

Author(s):

A. Płażek ◽

K. Hura ◽

T. Hura ◽

A. Słomka ◽

M. Hornyák ◽

...

Keyword(s):

Thermal Stress ◽

Heat Shock ◽

Heat Shock Proteins ◽

Photochemical Efficiency ◽

Fagopyrum Esculentum ◽

Common Buckwheat ◽

Hsp 70 ◽

Flower Bud ◽

Shock Proteins ◽

Hsp 90

Common buckwheat (Fagopyrum esculentum Moench) is a valuable crop plant with cereal-like seed chemical composition; however, it is susceptible to thermal stress. The aim of the study was to determine whether heat-shock proteins HSP-90 and HSP-70 can protect common buckwheat against thermal stress during development of microspores and embryo sacs. The study was performed on two accessions of common buckwheat, Panda and PA15, which differed in their tolerance to thermal stress. Accumulation of these proteins was determined in buds, open and wilted flowers, and donor leaves of plants grown at 20°C (control) and 30°C (thermal stress). Photochemical efficiency of donor leaves, closest to the inflorescences, based on chlorophyll a fluorescence (ChlF) was also analysed. All plants demonstrated higher values of ChlF at 30°C than at 20°C, which suggests that this 30°C temperature is more conducive to their vegetative growth. Pollen grains of both accessions demonstrated normal development at 30°C, whereas embryo sacs showed many developmental disturbances. Panda was more sensitive to thermal stress than PA15, as manifested in a higher percentage of degenerated embryo sacs at the flower bud phase. Moreover, a decrease in both HSPs in the studied organs of Panda was found relative to the control. At 30°C, both accessions accumulated more HSP-70 than HSP-90. These results suggest that, under heat stress, HSP-70 plays a protective role for flowers of common buckwheat. The analyses indicated that the donor leaf closest to the flower cluster may be a reliable indicator of temperature sensitivity in buckwheat flowers.

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