scholarly journals Expression of small heat shock-related protein 20 (HSP20) in rat myometrium is markedly decreased during late pregnancy and labour

Reproduction ◽  
2007 ◽  
Vol 133 (4) ◽  
pp. 807-817 ◽  
Author(s):  
B E Cross ◽  
H M O’Dea ◽  
D J MacPhee
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Longitudinal Muscle ◽  
Post Partum ◽  
Muscle Relaxation ◽  
Late Pregnancy ◽  
Smooth Muscle Relaxation ◽  
Pregnant Rats ◽  
Longitudinal Muscle Layer ◽  
Mrna Detection

The underlying mechanisms regulating uterine contractions during labour are still poorly understood. Heat shock protein 20 (HSP20) is known to be present at high levels in smooth muscle and implicated in muscle relaxation, but HSP20 expression in the myometrium is completely undetermined. Since HSP20 has been implicated in smooth muscle relaxation, we hypothesized that HSP20 would be highly expressed in the rat myometrium during early and mid-pregnancy when the myometrium is relatively quiescent. Northern blot analysis particularly demonstrated that HSP20 mRNA detection was significantly decreased from day (d) 22 of pregnancy to 1-daypost-partum(PP) compared with d6 (P< 0.05). HSP20 mRNA detection was also significantly decreased from d22 to d23 of gestation compared with non-pregnant (NP) samples. Immunoblot analysis showed that detection of HSP20 was significantly decreased at d23 compared with d12 and d15 (P< 0.05). HSP20 detection also significantly decreased at PP compared with d15 (P< 0.05). Immunofluorescence analysis demonstrated that after d15, plasma membrane-associated localization of HSP20 decreased markedly in both circular and longitudinal muscle layers. In addition, HSP20 was detectable near cell membranes at much higher levels in the longitudinal muscle layer of progesterone-treated pregnant rats (delayed labour) at all gestational time points examined, compared with controls. Our results demonstrate that HSP20 mRNA and protein are highly expressed during early and mid-pregnancy and then the expression markedly decreases during late pregnancy and labour. The observed patterns of HSP20 expression are consistent with a potential role for HSP20 in facilitating myometrium quiescence during early and mid-pregnancy.

scholarly journals The small heat shock-related protein, HSP20, is a cAMP-dependent protein kinase substrate that is involved in airway smooth muscle relaxation

2008 ◽  
Vol 294 (1) ◽  
pp. L69-L78 ◽  
Author(s):  
Padmini Komalavilas ◽  
Raymond B. Penn ◽  
Charles R. Flynn ◽  
Jeffrey Thresher ◽  
Luciana B. Lopes ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Airway Smooth Muscle ◽  
Fluorescent Protein ◽  
Muscle Relaxation ◽  
Stress Fibers ◽  
Smooth Muscle Relaxation ◽  
Related Protein ◽  
Kinase Substrate ◽  
Pka Pathway

Activation of the cAMP/cAMP-dependent PKA pathway leads to relaxation of airway smooth muscle (ASM). The purpose of this study was to examine the role of the small heat shock-related protein HSP20 in mediating PKA-dependent ASM relaxation. Human ASM cells were engineered to constitutively express a green fluorescent protein-PKA inhibitory fusion protein (PKI-GFP) or GFP alone. Activation of the cAMP-dependent signaling pathways by isoproterenol (ISO) or forskolin led to increases in the phosphorylation of HSP20 in GFP but not PKI-GFP cells. Forskolin treatment in GFP but not PKI-GFP cells led to a loss of central actin stress fibers and decreases in the number of focal adhesion complexes. This loss of stress fibers was associated with dephosphorylation of the actin-depolymerizing protein cofilin in GFP but not PKI-GFP cells. To confirm that phosphorylated HSP20 plays a role in PKA-induced ASM relaxation, intact strips of bovine ASM were precontracted with serotonin followed by ISO. Activation of the PKA pathway led to relaxation of bovine ASM, which was associated with phosphorylation of HSP20 and dephosphorylation of cofilin. Finally, treatment with phosphopeptide mimetics of HSP20 possessing a protein transduction domain partially relaxed precontracted bovine ASM strips. In summary, ISO-induced phosphorylation of HSP20 or synthetic phosphopeptide analogs of HSP20 decreases phosphorylation of cofilin and disrupts actin in ASM, suggesting that one possible mechanism by which HSP20 mediates ASM relaxation is via regulation of actin filament dynamics.

scholarly journals Induction of expression and phosphorylation of heat shock protein B5 (CRYAB) in rat myometrium during pregnancy and labour

Reproduction ◽  
2016 ◽  
Vol 152 (1) ◽  
pp. 69-79 ◽  
Author(s):  
J G Nicoletti ◽  
B G White ◽  
E I Miskiewicz ◽  
D J MacPhee
Keyword(s):  
Heat Shock ◽  
Protein Expression ◽  
Post Partum ◽  
Focal Adhesions ◽  
Late Pregnancy ◽  
Immunoblot Analysis ◽  
Small Molecular Weight ◽  
Pregnant Rats ◽  
Immune System Activation ◽  
Cryab Protein

During pregnancy the myometrium undergoes a programme of differentiation induced by endocrine, cellular, and biophysical inputs. Small heat shock proteins (HSPs) are a family of ten (B1–B10) small-molecular-weight proteins that not only act as chaperones, but also assist in processes such as cytoskeleton rearrangements and immune system activation. Thus, it was hypothesized that HSPB5 (CRYAB) would be highly expressed in the rat myometrium during the contractile and labour phases of myometrial differentiation when such processes are prominent. Immunoblot analysis revealed that myometrial CRYAB protein expression significantly increased from day (D) 15 to D23 (labour;P<0.05). In correlation with these findings, serine 59-phosphorylated (pSer59) CRYAB protein expression significantly increased from D15 to D23, and was also elevated 1-day post-partum (P<0.05). pSer59-CRYAB was detected in the cytoplasm of myocytes within both uterine muscle layers mid- to late-pregnancy. In unilaterally pregnant rats, pSer59-CRYAB protein expression was significantly elevated in the gravid uterine horns at both D19 and D23 of gestation compared with non-gravid horns. Co-immunolocalization experiments using the hTERT-human myometrial cell line and confocal microscopy demonstrated that pSer59-CRYAB co-localized with the focal adhesion protein FERMT2 at the ends of actin filaments as well as with the exosomal marker CD63. Overall, pSer59-CRYAB is highly expressed in myometrium during late pregnancy and labour and its expression appears to be regulated by uterine distension. CRYAB may be involved in the regulation of actin filament dynamics at focal adhesions and could be secreted by exosomes as a prelude to involvement in immune activation in the myometrium.

Expression of the Heat Shock Protein, HSPB1, Is Associated with Impaired Smooth Muscle Relaxation

2010 ◽  
Vol 158 (2) ◽  
pp. 361-362
Author(s):  
S. Rizvi ◽  
P. Komalavilas ◽  
R. Guzman ◽  
J. Dattilo ◽  
C. Brophy
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Muscle Relaxation ◽  
Smooth Muscle Relaxation

scholarly journals PS232. Expression of the Heat Shock Protein HSPB1 Is Associated With Impaired Smooth Muscle Relaxation

2010 ◽  
Vol 51 (6) ◽  
pp. 78S-79S
Author(s):  
Syed Z. Rizvi ◽  
Kyle M. Hocking ◽  
Erica Morley ◽  
Padmini Komalavilas ◽  
Joyce Cheung-Flynn ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Muscle Relaxation ◽  
Smooth Muscle Relaxation

scholarly journals A.122 Vascular effects of propofol: smooth muscle relaxation in human isolated veins and arteries

1996 ◽  
Vol 76 ◽  
pp. 38-39
Author(s):  
Eric Le Pelley ◽  
Pierre Corbi ◽  
Thierry Chataigneau ◽  
Robert Tricoche ◽  
Jacques Fusciardi
Keyword(s):  
Smooth Muscle ◽  
Muscle Relaxation ◽  
Smooth Muscle Relaxation ◽  
Vascular Effects

216Acute administration of estradiol induces bladder smooth muscle relaxation through non-genomic pathways

2005 ◽  
Vol 4 (3) ◽  
pp. 56
Author(s):  
M. Dambros ◽  
P. Palma ◽  
C. Riccetto ◽  
R. Fraga ◽  
M. Thiel ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Muscle Relaxation ◽  
Smooth Muscle Relaxation ◽  
Bladder Smooth Muscle
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