Abstract 19822: Arterial Calcification Can Be Inhibited via Stress Protein Induction Through a PPAR-dependent Pathway

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Kenneth Lim ◽  
Jen Xu ◽  
E-Jay Kao ◽  
Tianqing Kong ◽  
Tzongshi Lu

Introduction: Cardiovascular disease occurs prematurely in chronic inflammatory conditions such as Chronic Kidney Disease (CKD) and unfortunately, remains the leading cause of death in these patients. Vascular calcification (VC) is a significant contributor to cardiovascular mortality in CKD patients with the sequela of arterial hardening, congestive heart failure and sudden cardiac death. We recently reported that heat shock protein 72 (HSP72) when inducted, can inhibit the development of VC. Hypothesis: We hypothesize that HSP72 exerts its vasculo-protective effects by functioning as a molecular chaperon for peroxisome proliferator-activated receptor γ (PPARγ). Methods: We developed an in vitro long-term calcification model using HA-SMCs treated with calcification medium (CM) containing 5mM CaCl2 and 5mM β-glycerophosphate for 21 days. Cells were subjected to heat shock treatment at 43°C for 30 minutes daily to induce HSP72. Calcification was assessed qualitatively by alizarin red staining and quantitatively by the arsenazo III method. Results: Our results show that inducible HSP72 is significantly expressed following heat shock treatment in HA-SMCs. Induction of HSP72 inhibited the development of VC in our long-term calcification model and these effects were abolished by HSP72 siRNA, in vitro. We next showed that HSP72 formed a protein-protein complex with PPARγ by co-immunoprecipitation. Expression of both these proteins was down-regulated in calcific HA-SMCs and their gene expression was down regulated in atherosclerotic human arteries. Furthermore, we found that the PPARγ inhibitor, FABP4 (fatty acid binding protein-4) which function as an atherosclerosis promoter was up-regulated in calcified human arteries. Lastly, induction of HSP72 restored expression of the HSP72-PPARγ complex and inhibited upregulation of FABP4 with reduction in calcification in our in vitro calcification model. These vasculo-protective effects were abolished by HSP72 siRNA. Conclusion: HSP72 is a powerful inhibitor of VC and exerts its vasculo-protective effects by functioning as a molecular chaperon to stabilize PPARγ and regulate the PPARγ-FABP4 pathway. We suggest treatment strategies involving induction of HSP72 as a new approach to inhibit VC.

Circulation ◽  
2000 ◽  
Vol 102 (suppl_3) ◽  
Author(s):  
Ken Suzuki ◽  
Ryszard T. Smolenski ◽  
Jay Jayakumar ◽  
Bari Murtuza ◽  
Nigel J. Brand ◽  
...  

Background —Graft survival after skeletal myoblast transplantation is affected by various pathological processes caused by environmental stress. Heat shock is known to afford protection of several aspects of cell metabolism and function. We hypothesized that prior heat shock treatment of graft cells would improve their survival after cell transplantation. Methods and Results —L6 rat skeletal myoblasts expressing β-galactosidase (β-gal) were subjected to heat shock (42°C, 1 hour). Increased expression of heat shock protein 72 was detected 24 hours later in the heat-shocked cells. After hypoxia-reoxygenation in vitro, lactate dehydrogenase leakage was significantly attenuated in the heat-shocked cells; in addition, the percentage of early apoptosis was lower in this group measured by flow cytometry with annexin V staining. For the in vivo study, 1×10 6 heat-shocked (hsCTx) or normal-cultured (CTx) myoblasts were infused into the explanted rat hearts through the coronary artery followed by heterotopic heart transplantation. β-gal activity was significantly higher in the hsCTx group after cell transplantation, with an estimated 8×10 6 surviving cells per heart in the hsCTx group and 5×10 6 cells in the CTx group on day 28. Discrete loci of grafted cells were globally observed in the myocardium of the hsCTx and CTx groups, with a higher frequency in the hsCTx group. Surviving myoblasts occasionally differentiated into myotubes and had integrated with the native cardiomyocytes. Conclusions —Heat-shocked skeletal myoblasts demonstrated improved tolerance to hypoxia-reoxygenation insult in vitro and enhanced survival when grafted into the heart. Heat shock treatment could be useful in improving graft cell survival in cell transplantation.


2019 ◽  
Vol 79 (4) ◽  
pp. 753-758 ◽  
Author(s):  
Jianfei Chen ◽  
Shujun Zhang ◽  
Xiaoyu Han ◽  
Liang Zhang ◽  
Yongzhen Peng

Abstract In this study, the side-stream heat-shock treatment was used to start up and maintain the nitritation of real sewage. Complete nitrification was obtained when the real sewage was treated in a sequencing batch reactor (SBR). Then, about 50% of the mixed sludge was collected from the SBR and treated with the heat-shock treatment at 60 °C for 40 min in another reactor every 2 weeks. After providing the heat-shock treatment for four times, the effluent nitrate in the SBR gradually decreased from 22.5 to 3.2 mg/L, while the nitrite accumulation rate increased from 4.4% to 81.8%, indicating a successful start-up of nitritation. Further, the sewage nitritation was stable with the regular side-steam heat-shock treatment for 91 days, and the ammonium removal efficiency of 80.6% and nitrite accumulation rate of 91.2% were achieved. This study suggests that the side-stream heat-shock treatment could be used to start up sewage nitritation and maintain stability for a long-term operation.


2019 ◽  
Author(s):  
Henan Su ◽  
Guo Chen ◽  
Xing Liu ◽  
Limei Yang ◽  
Mu Zhuang ◽  
...  

Abstract Background Microspore embryogenesis (ME) provides an efficient way to breed crops. In many cases, short-term heat shock treatment can greatly increase the embryogenesis rate of brassicas. However, its molecular mechanism is largely unclear. Results To mine for the key genes, pathways and interplay in the underlying networks, we compared the proteomes of isolated microspores with samples pre-treated at 32 °C for 24 h and 25 °C for 24 h using two cabbage accessions (Zhonggan 628 and 87-534) showing extremely different embryogenic rates. The embryo yield was 0 and 19.7 embryos/bud for Zhonggan 628 at 25 °C and 32 °C, respectively, and was 0 for 87-534 at both temperatures. Using a label-free proteomics technology, more differentially expressed proteins (DEPs) were found for Zhonggan 628 (363 DEPs, 115 upregulated and 248 downregulated) than for 87-534 (282 DEPs, 162 upregulated and 120 downregulated). 97 DEPs specially identified only in Zhonggan 628 but not in 87-534 after heat-shock treatment were the key proteins that maybe related to heat shock-induced embryogenesis in vitro culture. Those 97 DEPs were mainly enriched in carbon metabolic process and protein synthesis and degradation process. Malate dehydrogenase (mMDH), sgt1 homolog B (SGT1), heat shock 70 kDa protein 5 (HSP70), and cell division control protein 48 homolog A (CDC48) may play an important role in cabbage embryogenesis and were identified based on pathway enrichment and protein−protein interaction analyses. In addition, changes in the abundance of 9 representative DEPs were correlated with their corresponding mRNA levels using qRT-PCR. Carbohydrate metabolism supplies the energy needed for the rapid growth that occurs during embryo development, and the folding of synthesized proteins or the refolding of damaged and unstable proteins occur, which may due to the stress induced by in vitro culture. Conclusions A set of putative proteins presumably specific for microspore embryogenesis induced by high temperature treatment were identified. In isolated microspore culture of cabbage, we present the first exposition of non-embryo and the embryo (induced by 32 °C heat shock treatment 24h) changes in the expression of specific proteins.


2015 ◽  
Vol 308 (12) ◽  
pp. C959-C963 ◽  
Author(s):  
Tsen-Ni Tsai ◽  
Tzu-Ying Lee ◽  
Maw-Shung Liu ◽  
Jia-Jing Ho ◽  
Li-Ju Huang ◽  
...  

Silver nanoparticles (Ag-nps) have been widely used in various biomedical products. Compared with its hazardous effects extensively being studied, rare attention has been paid to the potential protective effect of Ag-nps to human health. The present study was designed to evaluate the protective effects of Ag-nps and heat shock treatment on tumor necrosis factor-α (TNF-α)-induced cell damage in Clone 9 cells. Clone 9 cells were pretreated with nonlethal concentration of Ag-nps (1 μg/ml) or heat shock, and then cell damages were induced by TNF-α (1 ng/ml). Protective effects of Ag-nps administration or heat shock treatment were determined by examining the TNF-α-induced changes in cell viabilities. The results showed that the intensity of cytotoxicity produced by TNF-α was alleviated upon treatment with nonlethal concentration of Ag-nps (1 μg/ml). Similar protective effects were also found upon heat shock treatment. These data demonstrate that Ag-nps and heat shock treatment were equally capable of inducing heat shock protein 70 (HSP70) protein expression in Clone 9 cells. The results suggest that clinically Ag-nps administration is a viable strategy to induce endogenous HSP70 expression instead of applying heat shock. In conclusion, our study for the first time provides evidence that Ag-nps may act as a viable alternative for HSP70 induction clinically.


Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Nivaldo Ferreira do Nascimento ◽  
Rafaela Manchin Bertolini ◽  
Lucia Soares Lopez ◽  
Laura Satiko Okada Nakaghi ◽  
Paulo Sérgio Monzani ◽  
...  

Summary Triploidization plays an important role in aquaculture and surrogate technologies. In this study, we induced triploidy in the matrinxã fish (Brycon amazonicus) using a heat-shock technique. Embryos at 2 min post fertilization (mpf) were heat shocked at 38°C, 40°C, or 42°C for 2 min. Untreated, intact embryos were used as a control. Survival rates during early development were monitored and ploidy status was confirmed using flow cytometry and nuclear diameter analysis of erythrocytes. The hatching rate reduced with heat-shock treatment, and heat-shock treatments at 42°C resulted in no hatching events. Optimal results were obtained at 40°C with 95% of larvae exhibiting triploidy. Therefore, we report that heat-shock treatments of embryos (2 mpf) at 40°C for 2 min is an effective way to induce triploid individuals in B. amazonicus.


1988 ◽  
Vol 106 (4) ◽  
pp. 1105-1116 ◽  
Author(s):  
L A Mizzen ◽  
W J Welch

Exposure of mammalian cells to a nonlethal heat-shock treatment, followed by a recovery period at 37 degrees C, results in increased cell survival after a subsequent and otherwise lethal heat-shock treatment. Here we characterize this phenomenon, termed acquired thermotolerance, at the level of translation. In a number of different mammalian cell lines given a severe 45 degrees C/30-min shock and then returned to 37 degrees C, protein synthesis was completely inhibited for as long as 5 h. Upon resumption of translational activity, there was a marked induction of heat-shock (or stress) protein synthesis, which continued for several hours. In contrast, cells first made thermotolerant (by a pretreatment consisting of a 43 degrees C/1.5-h shock and further recovery at 37 degrees C) and then presented with the 45 degrees C/30-min shock exhibited considerably less translational inhibition and an overall reduction in the amount of subsequent stress protein synthesis. The acquisition and duration of such "translational tolerance" was correlated with the expression, accumulation, and relative half-lives of the major stress proteins of 72 and 73 kD. Other agents that induce the synthesis of the stress proteins, such as sodium arsenite, similarly resulted in the acquisition of translational tolerance. The probable role of the stress proteins in the acquisition of translational tolerance was further indicated by the inability of the amino acid analogue, L-azetidine 2-carboxylic acid, an inducer of nonfunctional stress proteins, to render cells translationally tolerant. If, however, analogue-treated cells were allowed to recover in normal medium, and hence produce functional stress proteins, full translational tolerance was observed. Finally, we present data indicating that the 72- and 73-kD stress proteins, in contrast to the other major stress proteins (of 110, 90, and 28 kD), are subject to strict regulation in the stressed cell. Quantitation of 72- and 73-kD synthesis after heat-shock treatment under a number of conditions revealed that "titration" of 72/73-kD synthesis in response to stress may represent a mechanism by which the cell monitors its local growth environment.


1986 ◽  
Vol 6 (1) ◽  
pp. 90-96 ◽  
Author(s):  
T McClanahan ◽  
K McEntee

Two Saccharomyces cerevisiae genes isolated in a differential hybridization screening for DNA damage regulation (DDR genes) were also transcriptionally regulated by heat shock treatment. A 0.45-kilobase transcript homologous to the DDRA2 gene and a 1.25-kilobase transcript homologous to the DDR48 gene accumulated after exposure of cells to 4-nitroquinoline-1-oxide (NQO; 1 to 1.5 microgram/ml) or brief heat shock (20 min at 37 degrees C). The DDRA2 transcript, which was undetectable in untreated cells, was induced to high levels by these treatments, and the DDR48 transcript increased more than 10-fold as demonstrated by Northern hybridization analysis. Two findings argue that dual regulation of stress-responsive genes is not common in S. cerevisiae. First, two members of the heat shock-inducible hsp70 family of S. cerevisiae, YG100 and YG102, were not induced by exposure to NQO. Second, at least one other DNA-damage-inducible gene, DIN1, was not regulated by heat shock treatment. We examined the structure of the induced RNA homologous to DDRA2 after heat shock and NQO treatments by S1 nuclease protection experiments. Our results demonstrated that the DDRA2 transcript initiates equally frequently at two sites separated by 5 base pairs. Both transcriptional start sites were utilized when cells were exposed to either NQO or heat shock treatment. These results indicate that DDRA2 and DDR48 are members of a unique dually regulated stress-responsive family of genes in S. cerevisiae.


1984 ◽  
Vol 4 (4) ◽  
pp. 591-598
Author(s):  
J Cappello ◽  
C Zuker ◽  
H F Lodish

The Dictyostelium genome contains 40 copies of a 4.7-kilobase repetitive and apparently transposable DNA sequence (DIRS-1) and about 250 smaller elements that appear to be deletions or rearrangements of DIRS-1. Transcripts of these sequences are induced during differentiation and also by heat shock treatment of growing cells. We showed that one such cloned element, pB41.6 (2.5 kilobases) contains a nucleotide sequence identical to the Drosophila consensus heat shock promotor. To test whether this sequence might indeed control the expression of DIRS-1-related RNAs, we have cloned this genomic segment into yeast cells. In yeast cells, 41.6 directs synthesis of a 1.7-kilobase RNA that is induced at least 10-fold by heat shock. Transcription initiates at about 124 bases 3' of the putative promotor sequence and terminates within the 41.6 insert. A 381-base-pair subclone that contains the putative promotor sequence is sufficient to induce the heat shock response of 41.6 in yeast cells.


Sign in / Sign up

Export Citation Format

Share Document