Pub Date : 2024-11-25DOI: 10.1016/j.peptides.2024.171324
Karl-Heinz Herzig
{"title":"The Viktor Mutt Award Lecture 2024 to Thomas Hökfelt.","authors":"Karl-Heinz Herzig","doi":"10.1016/j.peptides.2024.171324","DOIUrl":"https://doi.org/10.1016/j.peptides.2024.171324","url":null,"abstract":"","PeriodicalId":19765,"journal":{"name":"Peptides","volume":" ","pages":"171324"},"PeriodicalIF":2.8,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142739653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-22DOI: 10.1016/j.peptides.2024.171322
Patrícia Tancsics, Aliz Kovács, Miklós Palotai, Zsolt Bagosi
Corticotropin-releasing factor (CRF) activates the hypothalamic-pituitary-adrenal (HPA) axis and stimulates the noradrenergic neurotransmission, both processes being implicated in the pathogenesis of anxiety and depression, but the intimate site and mechanism of interaction of CRF and CRF-related peptides, named urocortins (UCN1, UCN2, UCN3), with noradrenaline (NA) was not fully elucidated yet. Therefore, the aim of the present study was to investigate the actions of CRF and urocortins on the NA released from the rat locus coeruleus (LC), the primary source of NA in the brain, and the participation of CRF receptors (CRF1 and CRF2) in these actions. In order to do so, male Wistar rats were used, their LC were isolated and dissected, and the LC slices were incubated with tritium-labelled NA, superfused and stimulated electrically. During superfusion, the LC slices were treated with CRF, UCN1, UCN2 or UCN3, and, when significant effect was observed, pretreated with selective CRF1 antagonist antalarmin or selective CRF2 antagonist astressin2B. The release of tritium-labelled NA from the LC was determined by liquid scintillation counting. CRF and UCN1 increased significantly the tritium-labelled NA release from the LC, and these effects were reduced by antalarmin, but not by astressin2B. In addition, UCN2, but not UCN3, decreased significantly the tritium-labelled NA release from the LC, and this effect was reversed by astressin2B, but not antalarmin. Our results indicate the existence of two apparently opposing CRF systems in the LC, since activation of CRF1 by CRF and UCN1 stimulated, whereas activation of CRF2 by UCN2 inhibited the NA release.
促肾上腺皮质激素释放因子(CRF)能激活下丘脑-垂体-肾上腺(HPA)轴,刺激去甲肾上腺素能神经递质,这两个过程都与焦虑和抑郁的发病机制有关,但CRF和CRF相关肽(即尿皮质素(UCN1、UCN2、UCN3))与去甲肾上腺素(NA)相互作用的密切部位和机制尚未完全阐明。因此,本研究旨在探究 CRF 和尿皮质素对大鼠脑内 NA 的主要来源--大鼠脑室(LC)释放的 NA 的作用,以及 CRF 受体(CRF1 和 CRF2)在这些作用中的参与情况。为此,研究人员使用雄性 Wistar 大鼠,分离并解剖了它们的 LC,用氚标记的 NA 培养 LC 切片,并对其进行灌注和电刺激。在超灌注过程中,用 CRF、UCN1、UCN2 或 UCN3 处理 LC 切片,并在观察到显著效果时,用选择性 CRF1 拮抗剂 antalarmin 或选择性 CRF2 拮抗剂 astressin2B 进行预处理。通过液体闪烁计数测定氚标记的 NA 从 LC 中的释放量。CRF 和 UCN1 能显著增加胰岛素管中氚标记 NA 的释放,antalarmin 能降低这些效应,但 astressin2B 却不能。此外,UCN2(而非 UCN3)能显著减少 LC 中氚标记 NA 的释放,而 astressin2B(而非 antalarmin)能逆转这种效应。我们的研究结果表明,LC中存在两种明显对立的CRF系统,因为CRF和UCN1激活CRF1会刺激NA的释放,而UCN2激活CRF2会抑制NA的释放。
{"title":"The effects of corticotropin-releasing factor (CRF) and urocortins on the noradrenaline (NA) released from the locus coeruleus (LC).","authors":"Patrícia Tancsics, Aliz Kovács, Miklós Palotai, Zsolt Bagosi","doi":"10.1016/j.peptides.2024.171322","DOIUrl":"https://doi.org/10.1016/j.peptides.2024.171322","url":null,"abstract":"<p><p>Corticotropin-releasing factor (CRF) activates the hypothalamic-pituitary-adrenal (HPA) axis and stimulates the noradrenergic neurotransmission, both processes being implicated in the pathogenesis of anxiety and depression, but the intimate site and mechanism of interaction of CRF and CRF-related peptides, named urocortins (UCN1, UCN2, UCN3), with noradrenaline (NA) was not fully elucidated yet. Therefore, the aim of the present study was to investigate the actions of CRF and urocortins on the NA released from the rat locus coeruleus (LC), the primary source of NA in the brain, and the participation of CRF receptors (CRF1 and CRF2) in these actions. In order to do so, male Wistar rats were used, their LC were isolated and dissected, and the LC slices were incubated with tritium-labelled NA, superfused and stimulated electrically. During superfusion, the LC slices were treated with CRF, UCN1, UCN2 or UCN3, and, when significant effect was observed, pretreated with selective CRF1 antagonist antalarmin or selective CRF2 antagonist astressin2B. The release of tritium-labelled NA from the LC was determined by liquid scintillation counting. CRF and UCN1 increased significantly the tritium-labelled NA release from the LC, and these effects were reduced by antalarmin, but not by astressin2B. In addition, UCN2, but not UCN3, decreased significantly the tritium-labelled NA release from the LC, and this effect was reversed by astressin2B, but not antalarmin. Our results indicate the existence of two apparently opposing CRF systems in the LC, since activation of CRF1 by CRF and UCN1 stimulated, whereas activation of CRF2 by UCN2 inhibited the NA release.</p>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":" ","pages":"171322"},"PeriodicalIF":2.8,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142710638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antimicrobial peptides (AMPs), particularly host defense peptides (HDPs), have gained recognition for their role in host defense mechanisms, but they have also shown potential as a promising anticancer, antiviral, antiparasitic, antifungal and immunomodulatory agent. Research studies in recent years have shown HDPs play a crucial role in endothelial cell function and biology. The function of endothelial cells is impacted by HDPs’ complex interplay between cytoprotective and cytotoxic actions as they are known to modulate barrier integrity, inflammatory response and angiogenesis. This biphasic response varies and depends on the peptide structure, its concentration, and the microenvironment. These effects are mediated through key signaling pathways, including MAPK, NF-κB, and PI3K/Akt, which controls responses such as cell proliferation, apoptosis, and migration. In the present review, we have discussed the significance of the intriguing relationship between HDPs and endothelial cell physiology which suggests it potential as a therapeutic agents for the treating wounds, cardiovascular diseases, and inflammation-related endothelial damage.
{"title":"Host defense peptides at the crossroad of endothelial cell physiology: Insight into mechanistic and pharmacological implications","authors":"Vivek Kumar Garg , Hemant Joshi , Amarish Kumar Sharma , Kiran Yadav , Vikas Yadav","doi":"10.1016/j.peptides.2024.171320","DOIUrl":"10.1016/j.peptides.2024.171320","url":null,"abstract":"<div><div>Antimicrobial peptides (AMPs), particularly host defense peptides (HDPs), have gained recognition for their role in host defense mechanisms, but they have also shown potential as a promising anticancer, antiviral, antiparasitic, antifungal and immunomodulatory agent. Research studies in recent years have shown HDPs play a crucial role in endothelial cell function and biology. The function of endothelial cells is impacted by HDPs’ complex interplay between cytoprotective and cytotoxic actions as they are known to modulate barrier integrity, inflammatory response and angiogenesis. This biphasic response varies and depends on the peptide structure, its concentration, and the microenvironment. These effects are mediated through key signaling pathways, including MAPK, NF-κB, and PI3K/Akt, which controls responses such as cell proliferation, apoptosis, and migration. In the present review, we have discussed the significance of the intriguing relationship between HDPs and endothelial cell physiology which suggests it potential as a therapeutic agents for the treating wounds, cardiovascular diseases, and inflammation-related endothelial damage.</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171320"},"PeriodicalIF":2.8,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.peptides.2024.171319
J. Michael Conlon, Peter R. Flatt
{"title":"Discovery of the bioactive form of glucagon-like peptide-1: An attempt to correct some misconceptions","authors":"J. Michael Conlon, Peter R. Flatt","doi":"10.1016/j.peptides.2024.171319","DOIUrl":"10.1016/j.peptides.2024.171319","url":null,"abstract":"","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171319"},"PeriodicalIF":2.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142625721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-01DOI: 10.1016/j.peptides.2024.171317
Othman Al Musaimi
Lasso peptides exhibit a range of bioactivities, including antiviral effects, inhibition of the glucagon receptor, blockade of the endothelin type B receptor, inhibition of myosin light chain kinase, and modulation of the atrial natriuretic factor, as well as notable antimicrobial properties. Intriguingly, lasso peptides exhibit remarkable proteolytic and thermal stability, addressing one of the key challenges that traditional peptides often face. The challenge in producing those valuable peptides remains the main hurdle in the way of producing larger quantities or even modifying them with more potent analogues. Genome mining and heterologous expression approaches have greatly facilitated the production of lasso peptides, moving beyond mere isolation techniques. This advancement not only allows for larger quantities but also enables the creation of additional analogues with improved stability and potency. This review aims to explore the unique bioactivities and stability of lasso peptides, along with recent advancements in genome mining and heterologous expression that address production challenges and open pathways for engineering potent analogues.
拉索肽具有一系列生物活性,包括抗病毒作用、抑制胰高血糖素受体、阻断 B 型内皮素受体、抑制肌球蛋白轻链激酶、调节心房利钠因子,以及显著的抗微生物特性。有趣的是,拉索肽具有显著的蛋白水解稳定性和热稳定性,解决了传统多肽经常面临的关键挑战之一。生产这些有价值的多肽所面临的挑战仍然是生产更多甚至用更强效的类似物对其进行改良的主要障碍。基因组挖掘和异源表达方法大大促进了套索肽的生产,超越了单纯的分离技术。这一进步不仅可以生产更多数量的拉索肽,还能创造出更多具有更高稳定性和效力的类似物。
{"title":"Lasso peptides realm: Insights and applications","authors":"Othman Al Musaimi","doi":"10.1016/j.peptides.2024.171317","DOIUrl":"10.1016/j.peptides.2024.171317","url":null,"abstract":"<div><div>Lasso peptides exhibit a range of bioactivities, including antiviral effects, inhibition of the glucagon receptor, blockade of the endothelin type B receptor, inhibition of myosin light chain kinase, and modulation of the atrial natriuretic factor, as well as notable antimicrobial properties. Intriguingly, lasso peptides exhibit remarkable proteolytic and thermal stability, addressing one of the key challenges that traditional peptides often face. The challenge in producing those valuable peptides remains the main hurdle in the way of producing larger quantities or even modifying them with more potent analogues. Genome mining and heterologous expression approaches have greatly facilitated the production of lasso peptides, moving beyond mere isolation techniques. This advancement not only allows for larger quantities but also enables the creation of additional analogues with improved stability and potency. This review aims to explore the unique bioactivities and stability of lasso peptides, along with recent advancements in genome mining and heterologous expression that address production challenges and open pathways for engineering potent analogues.</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171317"},"PeriodicalIF":2.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142569247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The co-evolution of social behavior and the immune system plays a critical role in individuals' adaptation to their environment. However, also need for further research on the key molecules that co-regulate social behavior and immunity. This study focused on neonatal mice that were separated from their mothers for 4 hours per day between the 6th and 16th day after birth. The results showed that these mice had lower plasma levels of IFN-γ and oxytocin, but higher levels of plasma glucocorticoids (GC), then impacting their social abilities. Additionally, maternal separation led to decreased levels of BDNF, IGF2, and CREB mRNAs in the hippocampus, while levels in the prefrontal cortex (PFC) remained unaffected. Maternal separation also resulted in increased levels of oxytocin and CRH mRNA in the hypothalamus, as well as an increase in CD45+ lymphocyte subsets in the meninges and choroid plexus (CP), with CD8+ lymphocytes in meninges and CD4+ lymphocytes in CP showing an increase. In IFN-γ-/- mice, a decrease in social preference was observed alongside lower plasma oxytocin levels. Moreover, IFN-γ-/- mice exhibited reduced numbers of oxytocin neurons in the paraventricular nucleus of the paraventricular nucleus of hypothalamus (PVN), decreased BDNF levels in the PFC and hippocampus, and alterations in CD45+ lymphocytes in CP and meninges, with an increase in CD8+ lymphocytes in meninges and CD4+ lymphocytes in CP. These findings highlight the immunological impact of social stress on IFN-γ regulation, suggesting that the immunomodulatory molecule IFN-γ may influence social behavior by affecting synaptic efficiency in brain regions such as the hippocampus and PFC, which are linked to oxytocin in the PVN.
{"title":"Maternal separation alters peripheral immune responses associated with IFN-γ and OT in mice","authors":"Yishu Zhang , HaiChao Chen , JiaXin Cao , LiPing Gao , YuHong Jing","doi":"10.1016/j.peptides.2024.171318","DOIUrl":"10.1016/j.peptides.2024.171318","url":null,"abstract":"<div><div>The co-evolution of social behavior and the immune system plays a critical role in individuals' adaptation to their environment. However, also need for further research on the key molecules that co-regulate social behavior and immunity. This study focused on neonatal mice that were separated from their mothers for 4 hours per day between the 6th and 16th day after birth. The results showed that these mice had lower plasma levels of IFN-γ and oxytocin, but higher levels of plasma glucocorticoids (GC), then impacting their social abilities. Additionally, maternal separation led to decreased levels of <em>BDNF</em>, <em>IGF2</em>, and <em>CREB</em> mRNAs in the hippocampus, while levels in the prefrontal cortex (PFC) remained unaffected. Maternal separation also resulted in increased levels of oxytocin and <em>CRH</em> mRNA in the hypothalamus, as well as an increase in CD45<sup>+</sup> lymphocyte subsets in the meninges and choroid plexus (CP), with CD8<sup>+</sup> lymphocytes in meninges and CD4<sup>+</sup> lymphocytes in CP showing an increase. In IFN-γ<sup>-/-</sup> mice, a decrease in social preference was observed alongside lower plasma oxytocin levels. Moreover, IFN-γ<sup>-/-</sup> mice exhibited reduced numbers of oxytocin neurons in the paraventricular nucleus of the paraventricular nucleus of hypothalamus (PVN), decreased <em>BDNF</em> levels in the PFC and hippocampus, and alterations in CD45<sup>+</sup> lymphocytes in CP and meninges, with an increase in CD8<sup>+</sup> lymphocytes in meninges and CD4<sup>+</sup> lymphocytes in CP. These findings highlight the immunological impact of social stress on IFN-γ regulation, suggesting that the immunomodulatory molecule IFN-γ may influence social behavior by affecting synaptic efficiency in brain regions such as the hippocampus and PFC, which are linked to oxytocin in the PVN.</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171318"},"PeriodicalIF":2.8,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142564342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-28DOI: 10.1016/j.peptides.2024.171312
Trinidad de los Ángeles Cordero Gil , María Soledad Moleón , Belkis Ester Marelli , Pablo Ariel Siroski
Amphibians and reptiles, like all animals, are prone to periodic infections. However, crocodilians stand out for their remarkable ability to remain generally healthy and infection-free despite frequent exposure to a wide variety of microorganisms in their habitats and often sustaining significant injuries. These animals have evolved highly active immune mechanisms that provide rapid and effective defense. This is evidenced by the superior hemolytic capacity of their plasma compared to that of other organisms. To date, several host defense peptides (HDPs) have been identified in crocodilians, including cathelicidins, beta-defensins, hepcidins, leucrocins, hemocidins, and omwaprins. These peptides exhibit potent and broad-spectrum antimicrobial, antibiofilm, antifungal, and anticancer activities. Due to the relatively low but diverse evolutionary rate of crocodilians, the HDPs found in this species offer valuable insights into proteins and mechanisms of action that are highly conserved across many animals related to immune defense. The potential applications of HDPs in modern medicine represent a promising strategy for developing new therapeutic agents. Their novelty and the vast variability with which peptide sequences can be designed and modified expand the field of application for HDPs almost infinitely. This review addresses the urgent need for innovative and more effective drugs to combat the rise of antimicrobialresistant infections and evaluates the potential of crocodilian HDPs. It presents recent advances in the identification of crocodilian HDPs, particularly antimicrobial peptides (AMPs), including previously underexplored topics such as the sequential and structural conformation of different peptide types in crocodilians and the use of bioinformatics tools to enhance native peptides
{"title":"Host defense peptides in crocodilians – A comprehensive review","authors":"Trinidad de los Ángeles Cordero Gil , María Soledad Moleón , Belkis Ester Marelli , Pablo Ariel Siroski","doi":"10.1016/j.peptides.2024.171312","DOIUrl":"10.1016/j.peptides.2024.171312","url":null,"abstract":"<div><div>Amphibians and reptiles, like all animals, are prone to periodic infections. However, crocodilians stand out for their remarkable ability to remain generally healthy and infection-free despite frequent exposure to a wide variety of microorganisms in their habitats and often sustaining significant injuries. These animals have evolved highly active immune mechanisms that provide rapid and effective defense. This is evidenced by the superior hemolytic capacity of their plasma compared to that of other organisms. To date, several host defense peptides (HDPs) have been identified in crocodilians, including cathelicidins, beta-defensins, hepcidins, leucrocins, hemocidins, and omwaprins. These peptides exhibit potent and broad-spectrum antimicrobial, antibiofilm, antifungal, and anticancer activities. Due to the relatively low but diverse evolutionary rate of crocodilians, the HDPs found in this species offer valuable insights into proteins and mechanisms of action that are highly conserved across many animals related to immune defense. The potential applications of HDPs in modern medicine represent a promising strategy for developing new therapeutic agents. Their novelty and the vast variability with which peptide sequences can be designed and modified expand the field of application for HDPs almost infinitely. This review addresses the urgent need for innovative and more effective drugs to combat the rise of antimicrobialresistant infections and evaluates the potential of crocodilian HDPs. It presents recent advances in the identification of crocodilian HDPs, particularly antimicrobial peptides (AMPs), including previously underexplored topics such as the sequential and structural conformation of different peptide types in crocodilians and the use of bioinformatics tools to enhance native peptides</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171312"},"PeriodicalIF":2.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142546691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.peptides.2024.171313
M. Gonzalez-Garcia , B. Bertrand , EM Martell-Huguet , JF Espinosa-Romero , RF Vázquez , F. Morales –Vicente , F. Rosenau , LH Standker , OL Franco , AJ Otero-Gonzalez , C Muñoz-Garay
Amidst the health crisis caused by the rise of multi-resistant pathogenic microorganisms, Antimicrobial Peptides (AMPs) have emerged as a potential alternative to traditional antibiotics. In this sense, Cm-p5 is an AMP with fungistatic activity against the yeast Candida albicans. Its antimicrobial activity and selectivity have been well characterized; however, the mechanism of action is still unknown. This study used biophysical approaches to gain insight into how this peptide exerts its activity. Stability and fluidity of lipid membrane were explored by liposome leakage and Laurdan generalized polarization (GP) respectively, suggesting that Cm-p5 does not perturb lipid membranes even at very high concentrations (≥100 µm.L−1). Likewise, no depolarizing action was observed using 3,3′-propil-2,2′-thyodicarbocianine, a potential membrane fluorescent reporter, with C. albicans cells or the corresponding liposome models. Changes in liposome size were analyzed by Dynamic Light Scattering (DLS) data, indicating that Cm-p5 covers the vesicular surface slightly increasing liposome hydrodynamic size, without liposome rupture. These results were further corroborated with Langmuir monolayer isotherms, where no significant changes in lateral pressure or area per lipid were detected, indicating little or no insertion. Finally, data obtained from molecular dynamics simulations aligned with in vitro observations, whereby Cm-p5 slightly interacted with the fungal membrane model surface without causing significant perturbation. These results suggest Cm-p5 is not a pore-forming anti-fungal peptide and that other mechanisms of action on the membrane as some limitation of fungal nutrition or receptor-dependent transduction for depressing growth development should be explored.
{"title":"Cm-p5, a molluscan-derived antifungal peptide exerts its activity by a membrane surface covering in a non-penetrating mode","authors":"M. Gonzalez-Garcia , B. Bertrand , EM Martell-Huguet , JF Espinosa-Romero , RF Vázquez , F. Morales –Vicente , F. Rosenau , LH Standker , OL Franco , AJ Otero-Gonzalez , C Muñoz-Garay","doi":"10.1016/j.peptides.2024.171313","DOIUrl":"10.1016/j.peptides.2024.171313","url":null,"abstract":"<div><div>Amidst the health crisis caused by the rise of multi-resistant pathogenic microorganisms, Antimicrobial Peptides (AMPs) have emerged as a potential alternative to traditional antibiotics. In this sense, Cm-p5 is an AMP with fungistatic activity against the yeast <em>Candida albicans</em>. Its antimicrobial activity and selectivity have been well characterized; however, the mechanism of action is still unknown. This study used biophysical approaches to gain insight into how this peptide exerts its activity. Stability and fluidity of lipid membrane were explored by liposome leakage and Laurdan generalized polarization (GP) respectively, suggesting that Cm-p5 does not perturb lipid membranes even at very high concentrations (≥100 µm.L<sup>−1</sup>). Likewise, no depolarizing action was observed using 3,3′-propil-2,2′-thyodicarbocianine, a potential membrane fluorescent reporter, with <em>C. albicans</em> cells or the corresponding liposome models. Changes in liposome size were analyzed by Dynamic Light Scattering (DLS) data, indicating that Cm-p5 covers the vesicular surface slightly increasing liposome hydrodynamic size, without liposome rupture. These results were further corroborated with Langmuir monolayer isotherms, where no significant changes in lateral pressure or area per lipid were detected, indicating little or no insertion. Finally, data obtained from molecular dynamics simulations aligned with <em>in vitro</em> observations, whereby Cm-p5 slightly interacted with the fungal membrane model surface without causing significant perturbation. These results suggest Cm-p5 is not a pore-forming anti-fungal peptide and that other mechanisms of action on the membrane as some limitation of fungal nutrition or receptor-dependent transduction for depressing growth development should be explored.</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171313"},"PeriodicalIF":2.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Several cell biology studies have focused on the effects of hypoxic environments on cardiomyocytes. However, the effect of anoxic conditions on cardiomyocytes remains largely unexplored. In the present study, we investigated the direct effects of anoxia on B-type natriuretic peptide (BNP) gene expression in cardiomyocytes. Neonatal rat cardiomyocytes (NRCMs) were exposed to anoxia using an airtight chamber saturated with 95 % N2/5 % CO2. BNP mRNA levels in NRCM were substantially reduced after more than 8 h of anoxia exposure, whereas after reoxygenation, BNP gene expression levels recovered in a time-dependent manner and significantly increased after 24 h of reoxygenation. BNP mRNA levels suppressed under anoxic conditions were significantly increased by aldosterone-induced activation of sodium-proton exchanger 1 (NHE1), which was canceled by an NHE1 inhibitor, suggesting that anoxia reduces BNP gene expression, at least in part, in an NHE1-dependent manner. In summary, we found that BNP gene expression in cardiomyocytes decreases under anoxic conditions, in contrast to previous research findings that BNP expression increases under hypoxic conditions. These findings reveal a new insight that, within a single heart tissue in various cardiovascular diseases, such as myocardial infarction, the biological responses of cardiomyocytes are fundamentally different in regions of anoxia and hypoxia.
{"title":"Suppression of B-type natriuretic peptide gene expression in cardiomyocytes under anoxic conditions","authors":"Rei Yasutake, Tomohisa Nagoshi, Akira Yoshii, Hirotake Takahashi, Yuhei Oi, Haruka Kimura, Yusuke Kashiwagi, Toshikazu D. Tanaka, Yoshiro Tanaka, Michihiro Yoshimura","doi":"10.1016/j.peptides.2024.171316","DOIUrl":"10.1016/j.peptides.2024.171316","url":null,"abstract":"<div><div>Several cell biology studies have focused on the effects of hypoxic environments on cardiomyocytes. However, the effect of anoxic conditions on cardiomyocytes remains largely unexplored. In the present study, we investigated the direct effects of anoxia on B-type natriuretic peptide (BNP) gene expression in cardiomyocytes. Neonatal rat cardiomyocytes (NRCMs) were exposed to anoxia using an airtight chamber saturated with 95 % N<sub>2</sub>/5 % CO<sub>2</sub>. BNP mRNA levels in NRCM were substantially reduced after more than 8 h of anoxia exposure, whereas after reoxygenation, BNP gene expression levels recovered in a time-dependent manner and significantly increased after 24 h of reoxygenation. BNP mRNA levels suppressed under anoxic conditions were significantly increased by aldosterone-induced activation of sodium-proton exchanger 1 (NHE1), which was canceled by an NHE1 inhibitor, suggesting that anoxia reduces BNP gene expression, at least in part, in an NHE1-dependent manner. In summary, we found that BNP gene expression in cardiomyocytes decreases under anoxic conditions, in contrast to previous research findings that BNP expression increases under hypoxic conditions. These findings reveal a new insight that, within a single heart tissue in various cardiovascular diseases, such as myocardial infarction, the biological responses of cardiomyocytes are fundamentally different in regions of anoxia and hypoxia.</div></div>","PeriodicalId":19765,"journal":{"name":"Peptides","volume":"182 ","pages":"Article 171316"},"PeriodicalIF":2.8,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}