scholarly journals Proteomic analysis of dietary restriction in yeast reveals a role for Hsp26 in lifespan extension

2021 ◽  
Author(s):  
Richard Campion ◽  
Leanne Bloxam ◽  
Kimberley Burrow ◽  
Philip Brownridge ◽  
Daniel Pentland ◽  
...  

Dietary restriction (DR) has been shown to increase lifespan in organisms ranging from yeast to mammals. This suggests that the underlying mechanisms may be evolutionarily conserved. Indeed, upstream signalling pathways, such as TOR, are strongly linked to DR-induced longevity in various organisms. However, the downstream effector proteins that ultimately mediate lifespan extension are less clear. To shed light on this, we used a proteomic approach on budding yeast. Our reasoning was that analysis of proteome-wide changes in response to DR might enable the identification of proteins that mediate its physiological effects, including replicative lifespan extension. Of over 2500 proteins we identified by liquid chromatography-mass spectrometry, 183 were significantly altered in expression by at least 3-fold in response to DR. Most of these proteins were mitochondrial and/or had clear links to respiration and metabolism. Indeed, direct analysis of oxygen consumption confirmed that mitochondrial respiration was increased several-fold in response to DR. In addition, several key proteins involved in mating, including Ste2 and Ste6, were downregulated by DR. Consistent with this, shmoo formation in response to α-factor pheromone was reduced by DR, thus confirming the inhibitory effect of DR on yeast mating. Finally, we found that Hsp26, a member of the conserved small heat shock protein (sHSP) family, was upregulated by DR and that overexpression of Hsp26 extended yeast replicative lifespan. As overexpression of sHSPs in Caenorhabditis elegans and Drosophila has previously been shown to extend lifespan, our data on yeast Hsp26 suggest that sHSPs may be universally conserved effectors of longevity.

2021 ◽  
Author(s):  
XianXu YANG ◽  
Zongze LI

Abstract MicroRNAs play a key role in the progress of bladder cancer (BC), which may lead to poor prognosis. A single MicroRNA can be used as an independent factor to regulate the progress of BC, while two MicroRNAs can have a synergistic regulatory effect on BC progress. It has been confirmed in our previous studies that miR-188-5p and miR-141-3p demonstrated high expressions in BC tissues and cells, which can promote the progress of BC and affect patient’s prognosis. As a follow-up research, this study has made further exploration in many aspects. We predicted and confirmed that miR-188-5p and miR-141-3p had a common target gene PTEN which had low expression in BC tissues and cells. Down regulation of PTEN can promote the progress of BC, and significantly reverse the inhibitory effect of down-regulated miR-188-5p and miR-141-3p on BC progress. PTEN is a cancer suppressor gene. Experiments further verified that pAKT and c-MYC were downstream effector proteins of PTEN, and their expressions increased with the decrease of PTEN expression. Experiments manifested that down-regulating miR-188-5p and miR-141-3p could significantly inhibit the volume and weight of subcutaneous tumors in mice, and half dose co-transfection of the two miRs made the tumor smaller and lighter. Therefore, it was concluded that miR-188-5p and miR-141-3p promoted the progress of BC synergistically by inhibiting PTEN to activate AKT/c-MYC pathway.


2005 ◽  
Vol 386 (2) ◽  
pp. 201-214 ◽  
Author(s):  
Zhou-shen ZHAO ◽  
Ed MANSER

The Rho GTPases are a family of molecular switches that are critical regulators of signal transduction pathways in eukaryotic cells. They are known principally for their role in regulating the cytoskeleton, and do so by recruiting a variety of downstream effector proteins. Kinases form an important class of Rho effector, and part of the biological complexity brought about by switching on a single GTPase results from downstream phosphorylation cascades. Here we focus on our current understanding of the way in which different Rho-associated serine/threonine kinases, denoted PAK (p21-activated kinase), MLK (mixed-lineage kinase), ROK (Rho-kinase), MRCK (myotonin-related Cdc42-binding kinase), CRIK (citron kinase) and PKN (protein kinase novel), interact with and are regulated by their partner GTPases. All of these kinases have in common an ability to dimerize, and in most cases interact with a variety of other proteins that are important for their function. A diversity of known structures underpin the Rho GTPase–kinase interaction, but only in the case of PAK do we have a good molecular understanding of kinase regulation. The ability of Rho GTPases to co-ordinate spatial and temporal phosphorylation events explains in part their prominent role in eukaryotic cell biology.


Aging Cell ◽  
2010 ◽  
Vol 10 (1) ◽  
pp. 39-54 ◽  
Author(s):  
Laurent Mouchiroud ◽  
Laurent Molin ◽  
Prasad Kasturi ◽  
Mohamed N. Triba ◽  
Marc Emmanuel Dumas ◽  
...  

Author(s):  
Bo Liu ◽  
Lijuan Lin ◽  
Shengjin Yu ◽  
Rongjun Xia ◽  
Linlin Zheng

The effects of long non-coding RNAs (lncRNAs) on the proliferation of hypertrophic scars have been described. However, the underlying mechanisms are not well characterized. The present study aimed to investigate the mechanisms of lncRNA H19 in hypertrophic scars. The effects of the lncRNA H19 on the proliferation and apoptosis of hypertrophic scar fibroblasts (HSFs) were analyzed using 5’-Ethynyl-2’-deoxyuridine staining, flow cytometry, and MTT. The results revealed H19 promoted the proliferation and inhibited the apoptosis in HSF. In addition, the binding associations between H19 and microRNA-194 (miR-194), and miR-194 and insulin-like growth factor-I receptor (IGF1R) were identified using bioinformatics screening and verified using dual-luciferase assays. Furthermore, the effects of the IGF1R knockdown on H19-induced HSF phenotypes and regulation over the p38 MAPK pathway were determined. Mechanistically, miR-194 was identified as the downstream effector of the H19-mediated phenotypes of HSFs through its ability to directly target IGF1R, thus modulating the p38 MAPK signaling pathway. In conclusion, the findings suggested that H19 may inhibit the apoptosis and promote the proliferation of HSFs through the miR-194/IGF1R/p38 MAPK signaling axis, thereby contributing to the progression of hypertrophic scars. These findings may provide novel targets for the treatment of hypertrophic scars.


2002 ◽  
Vol 50 (4) ◽  
pp. 481-489 ◽  
Author(s):  
Cs. Jeney ◽  
Boglárka Banizs ◽  
Orsolya Dobay ◽  

The effects of bafilomycin A1 and of the reduced level of endosomal epsilon-COP (coatomer protein) on the infectivity of human adenovirus type 5 were investigated in Coxsackie adenovirus receptor- (CAR-) transfected Chinese hamster ovary (CHO) cells. The endosomal proton pump inhibitor bafilomycin A1 was able to cause only partial inhibition. Using ldlF cells (an epsilon-COP thermosensitive mutant CHO cell line) the reduction of epsilon-COP level also had partial inhibitory effect. Based on these results and comparing them to existing models of the adenovirus entry, we propose a refined model in which there are two pathways of adenoviral entry: the first one involves the epsilon-COP as the downstream effector of the acidification and can be blocked by bafilomycin A1 and the second one is a pH-independent pathway.


2021 ◽  
Author(s):  
Weiping Tao ◽  
Xuesong Zhang ◽  
Juan Ding ◽  
Shijian Yu ◽  
Peiqing Ge ◽  
...  

Abstract Background: BDNF/TrkB pathway dysregulation may be induced by hypoxia and inflammation, and play pivotal roles during the development of neurological disorders. Propofol is an anesthetic agent with neuro-protective properties. We aimed to verify whether propofol affected BDNF/TrkB pathway in neurons exposed to hypoxia or TNF-α.Methods: Primary rat hippocampal neurons and astrocytes were cultured and exposed to propofol followed by hypoxia or TNF-α treatment. The production of BDNF and the expression/truncation/phosphorylation of TrkB were measured. The underlying mechanisms such as ERK, CREB, p35 and Cdk5 were investigated.Results: In hippocampal neurons and astrocytes, hypoxia and TNF-α reduced the production of BDNF. Pretreatment of hippocampal neurons with 25μM propofol reversed the inhibitory effect of hypoxia or TNF-α on BDNF production. However, even 100μM propofol had no such effect in astrocytes. Further, we found that in hippocampal neurons hypoxia and TNF-α increased the phosphorylaion of ERK (p-ERK) and CREB at Ser142 (p-CREBSer142), while reduced the phosphorylation of CREB at Ser133 (p-CREBSer133), which were all reversed by 25μM propofol and 10μM ERK inhibitor. In addition, neither hypoxia nor TNF-α affected TrkB expression, truncation or phosphorylation in hippocampal neurons and astrocytes. However 50μM propofol induced TrkB phosphorylation without affecting its expression and truncation only in hippocampal neurons. Furthermore, we detected that in hippocampal neurons, 50μM propofol induced p35 expression and Cdk5 activation, and blockade of p35 or Cdk5 mitigated propofol-induced TrkB phosphorylation.Conclusions: Propofol, via ERK/CREB and p35/Cdk5, may modulate BDNF/TrkB pathway in hippocampal neurons that were exposed to hypoxia or TNF-α.


2021 ◽  
Vol 288 (1950) ◽  
Author(s):  
Edward R. Ivimey-Cook ◽  
Kris Sales ◽  
Hanne Carlsson ◽  
Simone Immler ◽  
Tracey Chapman ◽  
...  

Dietary restriction (DR) increases lifespan in a broad variety of organisms and improves health in humans. However, long-term transgenerational consequences of dietary interventions are poorly understood. Here, we investigated the effect of DR by temporary fasting (TF) on mortality risk, age-specific reproduction and fitness across three generations of descendants in Caenorhabditis elegans . We show that while TF robustly reduces mortality risk and improves late-life reproduction of the individuals subject to TF (P 0 ), it has a wide range of both positive and negative effects on their descendants (F 1 –F 3 ). Remarkably, great-grandparental exposure to TF in early life reduces fitness and increases mortality risk of F 3 descendants to such an extent that TF no longer promotes a lifespan extension. These findings reveal that transgenerational trade-offs accompany the instant benefits of DR, underscoring the need to consider fitness of future generations in pursuit of healthy ageing.


2020 ◽  
Author(s):  
Edward R. Ivimey-Cook ◽  
Kris Sales ◽  
Hanne Carlsson ◽  
Simone Immler ◽  
Tracey Chapman ◽  
...  

AbstractDietary restriction increases lifespan in a broad variety of organisms and improves health in humans. However, long-term transgenerational consequences of dietary interventions are poorly understood. Here we investigated the effect of dietary restriction by temporary fasting (TF) on mortality risk, age-specific reproduction and fitness across three generations of descendants in C. elegans. We show that while TF robustly reduces mortality risk and improves late-life reproduction in the parental generation (P0), it has a wide range of both positive and deleterious effects on future generations (F1-F3). Remarkably, great-grandparental exposure to TF in early-life reduces fitness and increases mortality risk of F3 descendants to such an extent that TF no longer promotes a lifespan extension. These findings reveal that transgenerational trade-offs accompany the instant benefits of dietary restriction underscoring the need to consider fitness of future generations in pursuit of healthy ageing.


2019 ◽  
Vol 6 (6) ◽  
pp. 190360 ◽  
Author(s):  
Liuliu Yan ◽  
Lulu Lu ◽  
Fangbin Hu ◽  
Dattatrya Shetti ◽  
Kun Wei

Osteoclasts are multinuclear giant cells that have unique ability to degrade bone. The search for new medicines that modulate the formation and function of osteoclasts is a potential approach for treating osteoclast-related bone diseases. Piceatannol (PIC) is a natural organic polyphenolic stilbene compound found in diverse plants with a strong antioxidant and anti-inflammatory effect. However, the effect of PIC on bone health has not been scrutinized systematically. In this study, we used RAW264.7, an osteoclast lineage of cells of murine macrophages, to investigate the effects and the underlying mechanisms of PIC on osteoclasts. Here, we demonstrated that PIC treatment ranging from 0 to 40 µM strongly inhibited osteoclast formation and bone resorption in a dose-dependent manner. Furthermore, the inhibitory effect of PIC was accompanied by the decrease of osteoclast-specific genes. At the molecular level, PIC suppressed the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK1/2), NF-κB p65, IκBα and AKT. Besides, PIC promoted the apoptosis of mature osteoclasts by inducing caspase-3 expression. In conclusion, our results suggested that PIC inhibited RANKL-induced osteoclastogenesis and bone resorption by suppressing MAPK, NF-κB and AKT signalling pathways and promoted caspase3-mediated apoptosis of mature osteoclasts, which might contribute to the treatment of bone diseases characterized by excessive bone resorption.


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