RESUMEN

TANK-binding kinase 1 (TBK1) is a serine/threonine kinase with well-established roles as a central player in innate immune signaling. Dysregulation of TBK1 activity has been implicated in a variety of pathophysiologic conditions, including cancer. Generally, TBK1 acts as an oncogene and increased TBK1 activity, indicated by increased phosphorylation at the Ser172 residue, can be observed in multiple human cancers. TBK1 can be activated either by autophosphorylation of Ser172 or transphosphorylation at this site by upstream kinases. Serving as a hub for integrating numerous extracellular and intracellular signals, TBK1 can be activated through multiple signaling pathways. However, the direct upstream kinase responsible for TBK1 activation remains elusive, which limits our comprehensive understanding of its activation mechanism and potential therapeutic application targeting TBK1-related signaling especially in cancer. In this review, we summarize the findings on mechanisms of TBK1 activation in cancer cells and recent discoveries that shed light on the direct upstream kinases promoting TBK1 activation.

RESUMEN

BACKGROUND: Vascular endothelial injury, a key factor in diabetic foot ulcers (DFUs) pathogenesis, is linked to the impaired proliferation and migration of vascular endothelial cells, modulated by hypoxia-inducible factor, growth factors, and inflammatory elements. OBJECTIVE: The present study assesses the role of SIKVAV (Ser-Ile-Lys-Val-Ala-Val), a peptide shown to enhance cell proliferation and migration, on mouse aortic endothelial cell (MAEC) and the corresponding molecular mechanisms. METHODS: MAEC were treated with SIKVAV at 0, 100, 200, 400, and 600 µg/mL for 0, 24, 48, and 72 h. Cell viability was tested using the CCK-8 assay. Proliferating cell nuclear antigen (PCNA), extracellular signal-regulated kinase 1/2 (ERK1/2), and protein kinase B (Akt) levels were measured by qRT-PCR and western blot. RESULTS: SIKVAV augmented PCNA mRNA expression and stimulated vascular endothelial cell proliferation in a concentration and time-dependent fashion. Furthermore, it amplified the expression of p-ERK1/2 and p-Akt, pivotal components of the mitogen-activated protein kinase (MAPK)/ERK1/2 and phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways. The inhibition of these pathways suppressed PCNA mRNA expression, cell proliferation rate, and decreased p-ERK1/2 and p-Akt levels, highlighting SIKVAV's role in promoting vascular endothelial cell proliferation via these pathways. CONCLUSION: The results of this study confirmed that SIKVAV grafted onto scaffolds can accelerate the proliferation of vascular endothelial cells for the therapy of skin wounds, and provide a theoretical basis for its application in ischemic disease as synthesized biomaterials scaffolds of tissue engineering.

RESUMEN

The division of the races, created for the economic and political purposes of justifying slavery and colonialism, is a deep, entrenched, social structure which creates and promotes white privilege and is one within which we all live. No one can be free from it. This presentation is rooted in the assumption that the problem of racism today is a problem of whiteness and that it is an examination of this construct, therefore, which needs to be central to seeking a solution to this destructive dynamic. The work required of whiteness and the letting go of privilege is essential if we are to dismantle the system of racism that is so embedded within our society. I argue this is no altruistic endeavour but that, whilst clearly doing untold harm to people of colour, such a system also limits and distorts the development and individuation of white individuals and the society in which we are citizens.

La division des races, qui a été créée dans le but économique et politique de justifier l'esclavage et le colonialisme, est une structure sociale profonde et bien enracinée qui crée et promeut le privilège blanc. C'est une structure dans laquelle nous vivons tous. Personne ne peut s'en libérer. Cette présentation est fondée sur l'hypothèse que le problème du racisme aujourd'hui est un problème de blanchité, et que c'est donc un examen de cette construction qui doit être central dans la recherche d'une solution à cette dynamique destructrice. Le travail qui est requis des personnes blanches et l'abandon des privilèges sont essentiels si nous voulons démanteler le système de racisme qui est si ancré dans notre société. Je soutiens qu'il ne s'agit pas d'une entreprise altruiste, mais que, tout en causant clairement un tort indicible aux personnes de couleur, un tel système limite et déforme également le développement et l'individuation des personnes blanches et de la société dans laquelle nous sommes citoyens.

La división de las razas, creada con fines económicos y políticos para justificar la esclavitud y el colonialismo, es una estructura social profunda y arraigada que crea y promueve el privilegio blanco y es una en la cual todos vivimos. Nadie puede liberarse de ella. Esta presentación se basa en el supuesto de que el problema del racismo actual es un problema del ser­blanco y que examinar esta construcción es, por lo tanto, fundamental para buscar una solución a esta dinámica destructiva. Para desmantelar el sistema de racismo, tan arraigado en nuestra sociedad, es esencial trabajar sobre el constructo ser­blanco y desprenderse de los privilegios que conlleva. Sostengo, que no se trata de una tarea altruista, debido a que, además de causar un daño incalculable a las personas de color, este sistema también limita y distorsiona el desarrollo y la individuación de los individuos blancos y de la sociedad de la que somos ciudadanos.

RESUMEN

We conducted a thorough genome-wide investigation of protein phosphorylation in the halotolerant bacterium Mangrovibacter phragmitis (MPH) ASIOC01, using the Fe-IMAC enrichment method combined with tandem mass spectrometry under low- and high-salinity conditions. The phosphoproteome comprises 86 unique phosphorylated proteins, crucially involving pathways such as glycolysis/gluconeogenesis, the citrate cycle, chaperones, ribosomal proteins, and cell division. This study represents the first and most extensive investigation to-date comparing the bacterial phosphoproteome under different osmotic conditions using a gel-free approach. We identified 45 unique phosphoproteins in MPH cultured in media containing 1 % NaCl, and 33 exclusive phosphoproteins in MPH cultured in media containing 5 % NaCl. Eight phosphoproteins were detected in both growth conditions. Analysis of high-confidence phosphosites reveals that phosphorylation predominantly occurs on serine residues (52.3 %), followed by threonine (35.1 %) and tyrosine (12.6 %) residues. Interestingly, 34 % of the phosphopeptides display multiple phosphosites. Currently, prokaryotic phosphorylation site prediction platforms like MPSite and NetPhosBac 1.0 demonstrate an average prediction accuracy of only 21 % when applied to our dataset. Fourteen phosphoproteins did not yield matches when compared against dbPSP 2.0 (database of Phosphorylation Sites in Prokaryotes), indicating that these proteins may be novel phosphoproteins. These unique proteins undergoing phosphorylation under high salinity growth conditions potentially enhance their adaptive capabilities to environmental challenges.

RESUMEN

In consideration of several serious side effects induced by the classical AF-2 involved "lock" mechanism, recently disclosed PPARγ-Ser273 phosphorylation mode of action has become an alternative and mainstream mechanism for currently PPARγ-based drug discovery and development with an improved therapeutic index. In this study, by virtue of structure-based virtual high throughput screening (SB-VHTS), structurally chemical optimization by targeting the inhibition of the PPARγ-Ser273 phosphorylation as well as in vitro biological evaluation, which led to the final identification of a chrysin-based potential hit (YGT-31) as a novel selective PPARγ modulator with potent binding affinity and partial agonism. Further in vivo evaluation demonstrated that YGT-31 possessed potent glucose-lowering and relieved hepatic steatosis effects without involving the TZD-associated side effects. Mechanistically, YGT-31 presented such desired therapeutic index, mainly because it effectively inhibited the CDK5-mediated PPARγ-Ser273 phosphorylation, selectively elevated the level of insulin sensitivity-related Glut4 and adiponectin but decreased the expression of insulin-resistance-associated genes PTP1B and SOCS3 as well as inflammation-linked genes IL-6, IL-1ß and TNFα. Finally, the molecular docking study was also conducted to uncover an interesting hydrogen-bonding network of YGT-31 with PPARγ-Ser273 phosphorylation-related key residues Ser342 and Glu343, which not only gave a clear verification for our targeting modification but also provided a proof of concept for the abovementioned molecular mechanism.

Asunto(s)

RESUMEN

Lysergic acid diethylamide (LSD) is a synthetic psychedelic compound with potential therapeutic value for psychiatric disorders. This study aims to establish Caenorhabditis elegans as an in vivo model for examining LSD's effects on locomotor behavior. Our results demonstrate that LSD is absorbed by C. elegans and that the acute treatment reduces animal speed, similar to the role of endogenous serotonin. This response is mediated in part by the serotonergic receptors SER-1 and SER-4. Our findings highlight the potential of this nematode as a new experimental model in psychedelic research.

Asunto(s)

RESUMEN

Herpetospermum pedunculosum seeds also known as Herpetospermum caudigerum Wall. is the mature seed of the Herpetospermum pedunculosum(Ser.) C. B. Clarke,Cucurbitaceae. Modern pharmacological studies have shown that H. pedunculosum has hepatoprotective, anti-inflammatory, anti-gout and antibacterial pharmacological activities. The biologically active chemical components include lignin compounds such as Herpetin, Herpetetrone, Herpetoriol and so on. The natural product displays considerable skeletal diversity and structural complexity, offering significant opportunities for novel drug discovery. Based on the multi-omics research strategy and the 'gene-protein-metabolite' research framework, the biosynthetic pathway of terpenoids and lignans in H. pedunculosum has has been elucidated at multiple levels. These approaches provide comprehensive genetic information for cloning and identification of pertinent enzyme genes. Furthermore, the application of multi-omics integrative approaches provides a scientific means to elucidate entire secondary metabolic pathways. We investigated the biosynthetic pathways of lignin and terpene components in H. pedunculosum and conducted bioinformatics analysis of the crucial enzyme genes involved in the biosynthetic process using genomic and transcriptomic data. We identified candidate genes for six key enzymes in the biosynthetic pathway. This review reports on the current literature on pharmacological investigations of H. pedunculosum, proposing its potential as an antidiabetic agent. Moreover, we conclude, for the first time, the identification of key enzyme genes potentially involved in the biosynthesis of active compounds in H. pedunculosum. This review provides a scientific foundation for the discovery of novel therapeutic agents from natural sources.

Asunto(s)

RESUMEN

A single strain of Candida anglica, isolated from cider, is available in international yeast collections. We present here seven new strains isolated from French PDO cheeses. For one of the cheese strains, we achieved a high-quality genome assembly of 13.7 Mb with eight near-complete telomere-to-telomere chromosomes. The genomes of two additional cheese strains and of the cider strain were also assembled and annotated, resulting in a core genome of 5966 coding sequences. Phylogenetic analysis showed that the seven cheese strains clustered together, away from the cider strain. Mating-type locus analysis revealed the presence of a MATa locus in the cider strain but a MATalpha locus in all cheese strains. The presence of LINE retrotransposons at identical genome position in the cheese strains, and two different karyotypic profiles resulting from chromosomal rearrangements were observed. Together, these findings are consistent with clonal propagation of the cheese strains. Phenotypic trait variations were observed within the cheese population under stress conditions whereas the cider strain was found to have a much greater capacity for growth in all conditions tested.

Asunto(s)

RESUMEN

Tumor angiogenesis, the formation of new blood vessels to support tumor growth and metastasis, is a complex process regulated by a multitude of signaling pathways. Dysregulation of signaling pathways involving protein kinases has been extensively studied, but the role of protein phosphatases in angiogenesis within the tumor microenvironment remains less explored. However, among angiogenic pathways, protein phosphatases play critical roles in modulating signaling cascades. This review provides a comprehensive overview of the involvement of protein phosphatases in tumor angiogenesis, highlighting their diverse functions and mechanisms of action. Protein phosphatases are key regulators of cellular signaling pathways by catalyzing the dephosphorylation of proteins, thereby modulating their activity and function. This review aims to assess the activity of the protein tyrosine phosphatases and serine/threonine phosphatases. These phosphatases exert their effects on angiogenic signaling pathways through various mechanisms, including direct dephosphorylation of angiogenic receptors and downstream signaling molecules. Moreover, protein phosphatases also crosstalk with other signaling pathways involved in angiogenesis, further emphasizing their significance in regulating tumor vascularization, including endothelial cell survival, sprouting, and vessel maturation. In conclusion, this review underscores the pivotal role of protein phosphatases in tumor angiogenesis and accentuate their potential as therapeutic targets for anti-angiogenic therapy in cancer.

Asunto(s)

RESUMEN

Innovative therapeutic strategies are urgently needed for Parkinson's disease due to limited efficacy of current treatments and a weak therapeutic pipeline. In this forum article, we propose targeting tyrosine hydroxylase phosphorylation as a novel mechanism of action to address this critical need.

Asunto(s)

RESUMEN

Follicle selection in chicken refers to the process of selecting a follicle to enter hierarchy from a cohort of small yellow follicles (SY) with a diameter of 6 to 8 mm. The follicle being selected will develop rapidly and ovulate. Follicle selection is a key stage affecting chicken egg-laying performance. Our previous study showed that the phosphorylation level of lysine (K)-specific demethylase 1A (LSD1) at serine 54 (LSD1Ser54p) was significantly increased in F6 follicles compared to prehierarchal SY follicles, but its function was unclear. Here, the mechanism of this modification, the effect of LSD1Ser54p dephosphorylation on gene expression profile of chicken hierarchal granulosa cells and the function of fibroblast growth factor 9 (FGF9) that is regulated by LSD1Ser54p were further investigated. The modification of LSD1Ser54p was predicted to be mediated by cyclin-dependent kinase 5 (CDK5) and glycogen synthase kinase 3 (GSK3). Treatment of chicken hierarchal granulosa cells with CDK5 inhibitor significantly decreased LSD1Ser54p level (P < 0.05) and LSD1Ser54p interacted with CDK5, suggesting that, in the granulosa cells of chicken hierarchal follicles, LSD1Ser54p modification was carried out by CDK5. When the LSD1Ser54p level decreased in the granulosa cells of chicken hierarchal follicles, both the mRNA expression of FGF9 and α-actinin 2 (ACTN2) and the H3K4me2 level in their promoter regions significantly increased (P < 0.05), indicating that this phosphorylation modification enhanced the demethylation activity of LSD1. Moreover, in chicken hierarchal granulosa cells, overexpression of chicken FGF9 stimulated their proliferation and increased the mRNA expression of hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (Hsd3b) and steroidogenic acute regulatory protein (StAR). This study collectively revealed that phosphorylation of LSD1 at serine 54 by CDK5 enhanced its demethylation activity in chicken ovarian granulosa cells and regulated genes including FGF9 that is engaged in chicken follicle selection.

Asunto(s)

RESUMEN

Pseudomonas aeruginosa is one of the leading causes of nosocomial infections worldwide and has emerged as a serious public health threat, due in large part to its multiple virulence factors and remarkable resistance capabilities. Stk1, a eukaryotic-type Ser/Thr protein kinase, has been shown in our previous work to be involved in the regulation of several signalling pathways and biological processes. Here, we demonstrate that deletion of stk1 leads to alterations in several virulence- and resistance-related physiological functions, including reduced pyocyanin and pyoverdine production, attenuated twitching motility, and enhanced biofilm production, extracellular polysaccharide secretion, and antibiotic resistance. Moreover, we identified AlgR, an important transcriptional regulator, as a substrate for Stk1, with its phosphorylation at the Ser143 site catalysed by Stk1. Intriguingly, both the deletion of stk1 and the mutation of Ser143 of AlgR to Ala result in similar changes in the above-mentioned physiological functions. Furthermore, assays of algR expression in these strains suggest that changes in the phosphorylation state of AlgR, rather than its expression level, underlie changes in these physiological functions. These findings uncover Stk1-mediated phosphorylation of AlgR as an important mechanism for regulating virulence and resistance in P. aeruginosa.

Asunto(s)

RESUMEN

BACKGROUND: The existing literature lacks consensus on the effectiveness of utilizing polymorphisms to enhance outcomes in in vitro fertilization (IVF), particularly regarding ovulation induction protocols, oocyte and embryo quality, and pregnancy rates. Therefore, the present pilot study aims to assess whether the composition of different gonadotropin preparations affects the ovarian stimulation protocol concerning follicle-stimulating hormone receptor (FSHR) Ser680Asn genotypes (Ser/Ser, Ser/Asn, and Asn/Asn), in terms of ovulation induction parameters, including oocyte maturation rate, embryo quality, and pregnancy rate. METHODOLOGY: A total of 94 IVF patients underwent treatment using a GnRH antagonist protocol with four distinct gonadotropin preparations: HMG, HMG/hCG, rFSH, and rFSH/hCG. Follicular fluid (FF) samples were pooled for each patient for analysis. RESULTS: No statistical differences in the FF hormonal profile (progesterone, testosterone, androstenedione, estradiol, FSH, hCG) among the FSHR genotypes were reported either separately for each protocol or in combination for the four different preparations of gonadotropins. The maturation rate of MII oocytes and embryo quality did not differ among women carrying either Ser/Ser, Ser/Asn, or Asn/Asn genotype (p-value=0.475, and p-value=1.000, respectively). Moreover, no statistically significant correlation was revealed among Ser/Ser, Ser/Asn, and Asn/Asn carriers and pregnancy rate (p = 0.588). CONCLUSIONS: FF hormonal analysis of women undergoing IVF using different ovulation induction protocols and carrying either Ser/Ser, Ser/Asn, or Asn/Asn genotype revealed no significant correlations, in terms of maturation rate of MII oocytes, embryo quality, and pregnancy rate, indicating that the FSHR Ser680Asn genotype does not constitute a biomarker for a positive pregnancy outcome. Therefore, the existence of a different mechanism for the expression of FSHR Ser680Asn genotypes in the FF hormonal profile related to stimulated cycles is implied.

RESUMEN

The brain responds to experience through modulation of synaptic transmission, that is synaptic plasticity. An increase in the strength of synaptic transmission is manifested as long-term potentiation (LTP), while a decrease in the strength of synaptic transmission is expressed as long-term depression (LTD). Most of the studies of synaptic plasticity have been carried out by induction via electrophysiological stimulation. It is largely unknown in which behavioural tasks such synaptic plasticity occurs. Moreover, some stimuli can induce both LTP and LTD, thus making it difficult to separately study the different forms of synaptic plasticity. Two studies have shown that an aversive memory task - inhibitory avoidance learning and contextual fear conditioning - physiologically and selectively induce LTP and an LTP-like molecular change, respectively, in the hippocampus in vivo. Here, we show that a non-aversive behavioural task - exploration of new space - physiologically and selectively elicits a biochemical change in the hippocampus that is a hallmark of LTP. Specifically, we found that exploration of new space induces an increase in the phosphorylation of GluA1(Ser831), without affecting the phosphorylation of GluA1(Ser845), which are biomarkers of early-LTP and not NMDAR-mediated LTD. We also show that exploration of new space engenders the phosphorylation of the translational regulator S6K and the expression of Arc, which are features of electrophysiologically-induced late-LTP in the hippocampus. Therefore, our results show that exploration of new space is a novel non-aversive behavioural paradigm that elicits molecular changes in vivo that are analogous to those occurring during early- and late-LTP, but not during NMDAR-mediated LTD.

Asunto(s)

RESUMEN

OBJECTIVE: Proteasome activation by the cAMP-dependent protein kinase (PKA) was long suggested and recent studies using both cell cultures and genetically engineered mice have established that direct phosphorylation of RPN6/PSMD11 at Serine14 (pS14-RPN6) mediates the activation of 26S proteasomes by PKA. Genetic mimicry of pS14-RPN6 has been shown to be benign at baseline and capable of protecting against cardiac proteinopathy in mice. Here we report the results from a comprehensive baseline characterization of the Rpn6S14A mice (S14A), the first animal model of genetic blockade of the activation of 26S proteasomes by PKA. METHOD: Wild type and homozygous S14A littermate mice were subjected to serial M-mode echocardiography at 1 through 7 months of age, to left ventricular (LV) catheterization via the carotid artery for assessment of LV mechanical performance, and to cardiac gravimetric analyses at 26 weeks of age. Mouse mortality and morbidity were monitored daily for up to one year. Males and females were studied in parallel. RESULTS: Mice homozygous for S14A were viable and fertile and did not show discernible developmental abnormalities or increased mortality or morbidity compared with their Rpn6 wild type littermates by at least one year of age, the longest cohort observed thus far. Neither serial echocardiography nor hemodynamic assessments detected a remarkable difference in cardiac morphometry and function between S14A and wild type littermate mice. No cardiac gravimetric difference was observed. CONCLUSION: The findings of the present study indicate that genetic blockade of the activation of 26S proteasomes by PKA is well tolerated by mice at baseline. Therefore, the S14A mouse provides a desirable genetic tool for further investigating the in vivo pathophysiological and pharmacological significance of pS14-RPN6.

RESUMEN

Recent research has focused extensively on employing Deep Learning (DL) techniques, particularly Convolutional Neural Networks (CNN), for Speech Emotion Recognition (SER). This study addresses the burgeoning interest in leveraging DL for SER, specifically focusing on Punjabi language speakers. The paper presents a novel approach to constructing and preprocessing a labeled speech corpus using diverse social media sources. By utilizing spectrograms as the primary feature representation, the proposed algorithm effectively learns discriminative patterns for emotion recognition. The method is evaluated on a custom dataset derived from various Punjabi media sources, including films and web series. Results demonstrate that the proposed approach achieves an accuracy of 69%, surpassing traditional methods like decision trees, Naïve Bayes, and random forests, which achieved accuracies of 49%, 52%, and 61% respectively. Thus, the proposed method improves accuracy in recognizing emotions from Punjabi speech signals.

Asunto(s)

RESUMEN

In addition to topography and climate, biogeographic dispersal has been considered to influence plant diversity in the Himalaya-Hengduan Mountains (HHM), yet, the mode and tempo of sky island dispersal and its influence on species richness has been little explored. Through phylogenetic analysis of Gaultheria ser. Trichophyllae, a sky island alpine clade within the HHM, we test the hypothesis that dispersal has affected current local species richness. We inferred the dynamics of biogeographic dispersal with correlation tests on direction, distance, occurrence time, and regional species richness. We found that G. ser. Trichophyllae originated at the end of the Miocene and mostly dispersed toward higher longitudes (eastward). In particular, shorter intra-regional eastward dispersals and longer inter-regional westward dispersals were most frequently observed. We detected a prevalence of eastward intra-region dispersals in both glacial periods and interglacials. These dispersals may have been facilitated by the reorganization of paleo-drainages and monsoon intensification through time. We suggest that the timing of dispersal corresponding to glacial periods and the prevalence of intra-region dispersal, rather than dispersal frequency, most influenced the pattern of species richness of G. ser. Trichophyllae. This study facilitates a more comprehensive understanding of biodiversity in the sky islands within the HHM.

Asunto(s)

RESUMEN

An acute toxicity study assessed the LC50 values for eight different amino acid ionic liquids (AAILs), featuring two cations, tetrabutylphosphonium [P4444] and tetrabutylammonium [N4444], coupled with four anions [PHE], [ASP], [SER], and [GLY]. According to the OECD 203 standard for acute fish toxicity tests with guppy fish (Poecilia reticulata, all the AAILs exhibited low toxicity levels, and were practically nontoxic and harmless. The LC50 values surpassed 100 mg/L and 1000 mg/L. This study provides valuable insights for industrial professionals in utilizing tetrabutylphosphonium-based amino acid ionic liquids [P4444] [AA] and tetrabutylammonium-based amino acid ionic liquids [N4444][AA] in chemical processes, indicating their safety in aquatic environments. These promising results highlight the potential of incorporating these AAILs into diverse chemical processes while ensuring minimal ecological impact.

RESUMEN

The 21st amino acid, selenocysteine (Sec), is synthesized on its dedicated transfer RNA (tRNASec). In bacteria, Sec is synthesized from Ser-tRNA[Ser]Sec by Selenocysteine Synthase (SelA), which is a pivotal enzyme in the biosynthesis of Sec. The structural characterization of bacterial SelA is of paramount importance to decipher its catalytic mechanism and its role in the regulation of the Sec-synthesis pathway. Here, we present a comprehensive single-particle cryo-electron microscopy (SPA cryoEM) structure of the bacterial SelA with an overall resolution of 2.69 Å. Using recombinant Escherichia coli SelA, we purified and prepared samples for single-particle cryoEM. The structural insights from SelA, combined with previous in vivo and in vitro knowledge, underscore the indispensable role of decamerization in SelA's function. Moreover, our structural analysis corroborates previous results that show that SelA adopts a pentamer of dimers configuration, and the active site architecture, substrate binding pocket, and key K295 catalytic residue are identified and described in detail. The differences in protein architecture and substrate coordination between the bacterial enzyme and its counterparts offer compelling structural evidence supporting the independent molecular evolution of the bacterial and archaea/eukarya Ser-Sec biosynthesis present in the natural world.

RESUMEN

The protective effects of hydrogen sulfide (H2S) against ischemic brain injury and its role in promoting angiogenesis have been established. However, the specific mechanism underlying these effects remains unclear. This study is designed to investigate the regulatory impact and mechanism of H2S on VEGFR2 phosphorylation. Following expression and purification, the recombinant His-VEGFR2 protein was subjected to LC-PRM/MS analysis to identify the phosphorylation sites of VEGFR2 upon NaHS treatment. Adenovirus infection was used to transfect primary rat brain artery endothelial cells (BAECs) with the Ad-VEGFR2WT, Ad-VEGFR2Y797F, and Ad-VEGFR2S799A plasmids. The expression of VEGFR2 and recombinant Flag-VEGFR2, along with Akt phosphorylation, cell proliferation, and LDH levels, was assessed. The migratory capacity and tube-forming potential of BAECs were assessed using wound healing, transwell, and tube formation assays. NaHS notably enhanced the phosphorylation of VEGFR2 at Tyr797 and Ser799 sites. These phosphorylation sites were identified as crucial for mediating the protective effects of NaHS against hypoxia-reoxygenation (H/R) injury. NaHS significantly enhanced the Akt phosphorylation, migratory capacity, and tube formation of BAECs and upregulated the expression of VEGFR2 and recombinant proteins. These findings suggest that Tyr797 and Ser799 sites of VEGFR2 serve as crucial mediators of H2S-induced pro-angiogenic effects and protection against H/R injury.

Asunto(s)