RESUMEN

Poly(ADP-ribose)polymerase-1 (PARP1) could be activated by binding to nucleic acids with specific sequences, thus catalyzing the poly-ADP-ribosylation (PARylation) of target proteins including PARP1 itself. Most of the previously reported electrochemical methods for the determination of PARP1 were relied on the electrostatic interactions, which required the pre-immobilization of DNA on an electrode for the capture of PARP1. Herein, we reported an "immobilization-free" electrochemical strategy for the assays of PARP1 on the basic of avidin-biotin interaction. Once PARP1 was activated by binding with the specific double-stranded DNA (dsDNA) in a homogeneous solution, the biotinylated nicotinamide adenine dinucleotide (biotin-NAD+) was transferred onto PARP1, resulting in the formation of biotinylated PAR polymers. The resulting biotinylated PAR polymers were then captured by a neutravidin (NA)-modified electrode through avidin-biotin interactions. The rich biotin moieties in the PAR polymers allowed for the capture of NA-modified silver nanoparticles (NA-AgNPs) through the avidin-biotin interactions. The surface-tethered AgNPs produced a well-defined electrochemical signal due to the characteristic solid-state Ag/AgCl process. The "immobilization-free", electrostatic interaction-independent electrochemical biosensor exhibited low background current, high sensitivity, and good stability. It has achieved the determination of PARP1 with a detection limit down to 0.7 mU. The biosensor was further applied to determine the inhibition efficiency of potential inhibitors with a satisfactory result. This method shows promising potential applications in PARP1-related clinical diagnosis and drug discovery.

RESUMEN

DNA-protein crosslinks (DPC) are common DNA lesions induced by various external and endogenous agents. One of the sources of DPC is the apurinic/apyrimidinic site (AP site) and proteins interacting with it. Some proteins possessing AP lyase activity form covalent complexes with AP site-containing DNA without borohydride reduction (suicidal crosslinks). We have shown earlier that tyrosyl-DNA phosphodiesterase 1 (TDP1) but not AP endonuclease 1 (APE1) is able to remove intact OGG1 from protein-DNA adducts, whereas APE1 is able to prevent the formation of DPC by hydrolyzing the AP site. Here we demonstrate that TDP1 can remove intact PARP2 but not XRCC1 from covalent enzyme-DNA adducts with AP-DNA formed in the absence of APE1. We also analyzed an impact of APE1 and TDP1 on the efficiency of DPC formation in APE1-/- or TDP1-/- cell extracts. Our data revealed that APE1 depletion leads to increased levels of PARP1-DNA crosslinks, whereas TDP1 deficiency has little effect on DPC formation.

RESUMEN

ADP-ribosylation is a reversible and dynamic post-translational modification mediated by ADP-ribosyltransferases (ARTs). Poly(ADP-ribose) polymerases (PARPs) are an important family of human ARTs. ADP-ribosylation and PARPs have crucial functions in host-pathogen interaction, especially in viral infections. However, the functions and potential molecular mechanisms of ADP-ribosylation and PARPs in Mycobacterium infection remain unknown. In this study, bioinformatics analysis revealed significantly changed expression levels of several PARPs in tuberculosis patients compared to healthy individuals. Moreover, the expression levels of these PARPs returned to normal following tuberculosis treatment. Then, the changes in the expression levels of PARPs during Mycobacterium infection were validated in Tohoku Hospital Pediatrics-1 (THP1)-induced differentiated macrophages infected with Mycobacterium model strains bacillus Calmette-Guérin (BCG) and in human lung adenocarcinoma A549 cells infected with Mycobacterium smegmatis (Ms), respectively. The mRNA levels of PARP9, PARP10, PARP12, and PARP14 were most significantly increased during infection, with corresponding increases in protein levels, indicating the possible biological functions of these PARPs during Mycobacterium infection. In addition, the biological function of host PARP9 in Mycobacterium infection was further studied. PARP9 deficiency significantly increased the infection efficiency and intracellular proliferation ability of Ms, which was reversed by the reconstruction of PARP9. Collectively, this study updates the understanding of changes in PARP expression during Mycobacterium infection and provides evidence supporting PARP9 as a potent suppressor for Mycobacterium infection. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-023-00112-2.

RESUMEN

Calpain and PARP-NF-κB signaling are reported to participate in the ischemic brain injury. In this study, it was investigated whether calpain was contributed to the neurovascular unit (NVU) damage through up-regulating PARP-NF-κB signaling during experimental ischemic stroke. Male Sprague-Dawley rats were suffered from 90 min of middle cerebral artery occlusion, followed by reperfusion. The NVU damage was evaluated by the permeability of blood-brain barrier (BBB), the degradation of proteins in extracellular matrix and tight junctions, and ultrastructural changes. The inflammatory response was determined by the expression of inflammatory genes driven by PARP-NF-κB signaling and the activities of myeloperoxidase (MPO). Treatment with MDL 28,170, a calpain inhibitor, improved neurological functions, reduced TUNEL staining index, lessened brain swelling, and decreased infarct volume in ischemic rats. Moreover, it reduced the BBB permeability, enhanced the levels of laminin, collagen IV and occludin, and attenuated the ultrastructural damage of NVU in penumbra and core after induction of ischemia. Meanwhile, it enhanced the levels of cytosolic IκBα, lessened the levels of nuclear PARP and NF-κB p65, reduced the levels of ICAM-1, TNF-α, IL-1ß, MMP-9, and MMP-2,and suppressed the activities of MPO in penumbra and core. These data showed that calpain inhibition suppressed PARP-NF-κB signaling-mediated inflammatory response, reduced NVU damage, and protected brain against ischemic stroke, suggesting the involvement of calpain in the NVU damage through up-regulating PARP-NF-κB signaling during brain ischemia.

RESUMEN

Purpose: This research aimed to ascertain the neuroprotective effect of histone deacetylase (HDAC) inhibition on retinal photoreceptors in Pde6brd1 mice, a model of retinitis pigmentosa (RP). Methods: Single-cell RNA-sequencing (scRNA-seq) explored HDAC and poly (ADP-ribose) polymerase (PARP)-related gene expression in both Pde6b-mutant rd1 and wild-type (WT) mice. The CUT&Tag method was employed to examine the functions of HDAC in rd1 mice. Organotypic retinal explant cultures from WT and rd1 mice were exposed to the HDAC inhibitor SAHA (suberoylanilide hydroxamic acid) postnatally, from day 5 to day 11. The terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assay was applied to quantify the percentage of photoreceptor loss in the outer nuclear layer (ONL). HDAC activity was confirmed to be inhibited by SAHA through an HDAC activity assay. Moreover, the study evaluated PARP activity, a key driver of the initial response to DNA damage during photoreceptor degeneration, following HDAC inhibition. Results: The scRNA-seq revealed that diverse roles of HDAC and PARP isoforms in photoreceptor cell death. HDAC-related genes appeared to regulate cell death and primary immunodeficiency. Alterations in HDAC activity were consistent with the TUNEL-positive cells in the ONL at different time points. Notably, SAHA significantly postponed photoreceptor loss and decreased HDAC and PARP activity, thereby implicating both in the same degenerative pathway. Conclusions: This study highlights that the interaction between HDAC inhibition and PARP can delay photoreceptor cell death, proposing a promising therapeutic approach for RP.

Asunto(s)

RESUMEN

The development of new treatments for gynecological malignancies has been conducted mainly through collaborative international phase III trials led by the United States and Europe. The survival outcomes of many gynecological malignancies have greatly improved as a result. Recent large-scale genome-wide association studies have revealed that drug efficacy and adverse event profiles are not always uniform. Thus, it is important to validate new treatment options in each country to safely and efficiently provide newly developed treatment options to patients with gynecological malignancies. The Japanese Gynecologic Oncology Group (JGOG) is conducting 5 cohort studies (JGOG 3026, 3027, 3028, 3030, and 3031) to establish real-world data (RWD) of poly(ADP-ribose) polymerase (PARP) inhibitor use in patients with advanced or recurrent epithelial ovarian cancer. The RWD constructed will be used to provide newly developed PARP inhibitors for women with advanced or recurrent ovarian cancer in a safer and more efficient manner as well as to develop further treatment options. In 2022, The JGOG, Korean Gynecologic Oncology Group, Chinese Gynecologic Cancer Society, and Taiwanese Gynecologic Oncology Group established the East Asian Gynecologic Oncology Trial Group to collaborate with East Asian countries in clinical research on gynecologic malignancies and disseminate new knowledge on gynecologic malignancies from Asia. The JGOG will conduct a collaborative integrated analysis of the RWD generated from Asian countries and disseminate real-world clinical knowledge regarding new treatment options that have been clinically implemented.

Asunto(s)

RESUMEN

Poly-ADP-ribosylation of proteins, mediated by the two ADP-ribosyltransferases PARP1 and PARP2 in response to DNA damage, has emerged as a critical mediator of the DNA damage response (DDR). Accordingly, considering the critical role of DDR in cancer, PARP inhibitors (PARPi) have become an important class of therapeutics. PARPi have largely been considered for their intrinsic actions to tumor cells per se. However, these compounds also affect the immune response to tumors. It is now an emerging evidence supporting immunomodulatory roles of PARP1 and PARP2 which can facilitate or impede tumor progression. In this chapter, we describe some protocols to study the immunomodulatory functions of PARP1 and PARP2 in mouse tumor models.

Asunto(s)

RESUMEN

OBJECTIVE: To investigate the in-depth pharma-cological mechanisms of celastrol in children neuro-blastoma treatment. METHODS: In the current study, we examined the effects of celastrol on children neuroblastoma cells viability and proliferation by cell counting kit-8 assay and colony formation assay. Annexin V-FTIC and PI staining were applied to determine cell apoptosis after celastrol treatment. ROS generation levels were examined by 2', 7'-dichloroflfluorescin diacetate. RESULTS: We found that celastrol could suppress the proliferation of children neuroblastoma cells with few effects on normal cell lines . Further mechanisms studies have shown that celastrol inhibited cell cycle progression and induced cell apoptosis in QDDQ-NM and SH-SY5Y cells. In addition, ROS production might involve in celastrol-mediated apoptotic cell death in children neuroblastoma cells by activating caspase death pathway. CONCLUSIONS: Our findings demonstrated that celastrol could promote ROS generation-induced apoptosis in neuroblastoma cell by activating caspase death pathway. These findings suggested that celastrol might be a potential novel anti-neuroblastoma agent with minor cytotoxicity.

Asunto(s)

RESUMEN

Since the concept, DNA damage repair has been stated as a natural biological event, and research has increasingly revealed its strong association to tumors, aging, immunity, biochemical detection, and other factors. The discovery of abnormal DNA repair in cancers has been heralded as a paradigm shift in the treatment of malignancies. A poly (ADP-ribose) polymerase (PARP) activates poly (ADP-ribosylation) to repair single-strand DNA breaks after DNA damage. In some cancers, such as breast cancer and gastric cancer, a PARP inhibitor can target the DNA damage response pathway, prevent DNA repair, and induce homologous recombination deficiency (HRD) tumors to create the phenomena of synthetic lethality. Increasingly, clinical trials are being submitted to research the uses of PARP inhibitors in various types of cancers. Small cell lung cancer (SCLC) is a quickly growing malignancy with numerous therapeutic limitations and a dismal prognosis. Sequencing of mutant genes revealed multiple gene connections that may contribute to its carcinogenesis, indicating a viable study direction. Furthermore, the therapy of SCLC with PARP inhibitors has been further explored. The mechanism of PARP action, as well as the advancement of its preclinical and clinical applications in SCLC, will be discussed in this review.

Asunto(s)

RESUMEN

Poly ADP-ribosylation (PARylation) is a post-translational modification process. Following the discovery of PARP-1, numerous studies have demonstrated the role of PARylation in the DNA damage and repair responses for cellular stress and DNA damage. Originally, studies on PARylation were confined to PARP-1 activation in the DNA repair pathway. However, the interplay between PARylation and DNA repair suggests that PARylation is important for the efficiency and accuracy of DNA repair. PARylation has contradicting roles; however, recent evidence implicates its importance in inflammation, metabolism, and cell death. These differences might be dependent on specific cellular conditions or experimental models used, and suggest that PARylation may play two opposing roles in cellular homeostasis. Understanding the role of PARylation in cellular function is not only important for identifying novel therapeutic approaches; it is also essential for gaining insight into the mechanisms of unexplored diseases. In this review, we discuss recent reports on the role of PARylation in mediating diverse cellular functions and homeostasis, such as DNA repair, inflammation, metabolism, and cell death.

Asunto(s)

RESUMEN

Oocyte quality is the limiting factor in female fertility. It is well known that maternal nutrition plays a role in reproductive function, and manipulating nutrition to improve fertility in livestock has been common practice in the past, particularly with respect to negative energy balance in cattle. A deficiency in nicotinamide adenine dinucleotide (NAD+) production has been associated with increased incidences of miscarriage and congenital defects in humans and mice, while elevating NAD+ through dietary supplements in aged subjects improved oocyte quality and embryo development. NAD+ is consumed by Sirtuins and poly-ADP-ribose polymerases (PARPs) within the cell and thus need constant replenishment in order to maintain various cellular functions. Sirtuins and PARPs play important roles in oocyte maturation and embryo development, and their activation may prove beneficial to in vitro embryo production and livestock breeding programs. This review examines the roles of NAD+, Sirtuins and PARPs in aspects of fertility, providing insights into the potential use of NAD+-elevating treatments in livestock breeding and embryo production programs.

Asunto(s)

RESUMEN

Primary liver cancer is the sixth most common cancer in men and seventh in women, with hepatocellular carcinoma (HCC) being the most common form (75-85% of primary liver cancer cases) and the most frequent etiology being viral infections (HBV and HCV). In 2020, mortality represented 92% of the incidence-830,180 deaths for 905,677 new cases. Few treatment options exist for advanced or terminal-stage HCC, which will receive systemic therapy or palliative care. Although radiotherapy is used in the treatment of many cancers, it is currently not the treatment of choice for HCC, except in the palliative setting. However, as radiosensitizing drugs, such as inhibitors of DNA repair enzymes, could potentiate the effects of RT in HCC by exploiting the modulation of DNA repair processes found in this tumour type, RT and such drugs could provide a treatment option for HCC. In this review, we provide an overview of PARP1 involvement in DNA damage repair pathway and discuss its potential implication in HCC. In addition, the use of PARP inhibitors and PARP decoys is described for the treatment of HCC and, in particular, in HBV-related HCC.

RESUMEN

PARP12 is a member of poly-ADP-ribosyl polymerase (PARPs), which has been characterized for its antiviral function. Yet its physiological implication in adipocytes remains unknown. Here, we report a central function of PARP12 in thermogenic adipocytes. We show that PARP12 is highly expressed in brown adipose tissue and is mainly localized to the mitochondria. Knockdown of PARP12 in vitro reduced UCP1 expression. In parallel, the deficiency of PARP12 reduced mitochondrial respiration in adipocytes, while overexpression of PARP12 reversed these effects.

Asunto(s)

RESUMEN

Poly-ADP-ribose-polymerases (PARPs) are a family of 17 enzymes that regulate a diverse range of cellular processes in mammalian cells. PARPs catalyze the transfer of ADP-ribose from NAD+ to target molecules, most prominently amino acids on protein substrates, in a process known as ADP-ribosylation. Identifying the direct protein substrates of individual PARP family members is an essential first step for elucidating the mechanism by which PARPs regulate a particular pathway in cells. Two distinct chemical genetic (CG) strategies have been developed for identifying the direct protein substrates of individual PARP family members. In this review, we discuss the design principles behind these two strategies and how target identification has provided novel insight into the cellular function of individual PARPs and PARP-mediated ADP-ribosylation.

Asunto(s)

RESUMEN

Poly (ADP-ribose) polymerase (PARP) is a DNA damage repair protein, and its inhibitors have shown promising results in clinical trials. The prognostic significance of PARP is inconsistent in studies of various cancers. In the present study, we conducted a systematic review and meta-analysis to reveal the prognostic and clinicopathological significance of PARP expression in multiple solid cancers. We searched the MEDLINE, EMBASE, and Cochrane databases for relevant research articles published from 2005 to 2021. The pooled hazard ratio (HR) with confidence interval (CI) was calculated to investigate the relationship between PARP expression and survival in multiple solid cancers. In total, 10,667 patients from 31 studies were included. A significant association was found between higher PARP expression and overall survival (OS) (HR = 1.54, 95% CI = 1.34-1.76, p < 0.001), disease-free survival (DFS) (HR = 1.15, 95% CI = 1.10-1.21, p < 0.001), and progression-free survival (PFS) (HR = 1.05, 95% CI = 1.03-1.08, p < 0.001). Subgroup analyses showed that PARP overexpression was significantly related to poor OS in patients with breast cancers (HR = 1.38, 95% CI = 1.28-1.49, p < 0.001), ovary cancers (HR = 1.21, 95% CI = 1.10-1.33, p = 0.001), lung cancers (HR = 2.11, 95% CI = 1.29-3.45, p = 0.003), and liver cancers (HR = 3.29, 95% CI = 1.94-5.58, p < 0.001). Regarding ethnicity, Asian people have almost twice their worst survival rate compared to Caucasians. The pooled odds ratio analysis showed a significant relationship between higher PARP expression and larger tumour size, poor tumour differentiation, lymph node metastasis, distant metastasis, higher TNM stage and lymphovascular invasion, and positive immunoreactivity for Ki-67, BRCA1, and BRCA2. In addition, nuclear expression assessed by the QS system using Abcam and Santa Cruz Biotechnology seems to be the most commonly used and reproducible IHC method for assessing PARP expression. This meta-analysis revealed that higher PARP expression was associated with a worse OS, DFS, and PFS in patients with solid cancers. Moreover, inhibition of this pathway through its specific inhibitors may extend the survival of patients with higher PARP expression.

RESUMEN

Nanotechnology has revolutionized novel drug delivery strategies through establishing nanoscale drug carriers, such as niosomes, liposomes, nanomicelles, dendrimers, polymeric micelles, and nanoparticles (NPs). Owing to their desirable cancer-targeting efficacy and controlled release, these nanotherapeutic modalities are broadly used in clinics to improve the efficacy of small-molecule inhibitors. Poly(ADP-ribose) polymerase (PARP) family members engage in various intracellular processes, including DNA repair, gene transcription, signal transduction, cell cycle regulation, cell division, and antioxidant response. PARP inhibitors are synthetic small-molecules that have emerged as one of the most successful innovative strategies for targeted therapy in cancer cells harboring mutations in DNA repair genes. Despite these advances, drug resistance and unwanted side effects are two significant drawbacks to using PARP inhibitors in the clinic. Recently, the development of practical nanotechnology-based drug delivery systems has tremendously improved the efficacy of PARP inhibitors. NPs can specifically accumulate in the leaky vasculature of the tumor and cancer cells and release the chemotherapeutic moiety in the tumor microenvironment. On the contrary, NPs are usually unable to permeate across the body's normal organs and tissues; hence the toxicity is zero to none. NPs can modify the release of encapsulated drugs based on the composition of the coating substance. Delivering PARP inhibitors without modulation often leads to the toxic effect; therefore, a delivery vehicle is essential to encapsulate them. Various nanocarriers have been exploited to deliver PARP inhibitors in different cancers. Through this review, we hope to cast light on the most innovative advances in applying PARP inhibitors for therapeutic purposes.

Asunto(s)

RESUMEN

Poly (ADP-ribose) polymerases (PARP) 1-3 are well-known multi-domain enzymes, catalysing the covalent modification of proteins, DNA, and themselves. They attach mono- or poly-ADP-ribose to targets using NAD+ as a substrate. Poly-ADP-ribosylation (PARylation) is central to the important functions of PARP enzymes in the DNA damage response and nucleosome remodelling. Activation of PARP happens through DNA binding via zinc fingers and/or the WGR domain. Modulation of their activity using PARP inhibitors occupying the NAD+ binding site has proven successful in cancer therapies. For decades, studies set out to elucidate their full-length molecular structure and activation mechanism. In the last five years, significant advances have progressed the structural and functional understanding of PARP1-3, such as understanding allosteric activation via inter-domain contacts, how PARP senses damaged DNA in the crowded nucleus, and the complementary role of histone PARylation factor 1 in modulating the active site of PARP. Here, we review these advances together with the versatility of PARP domains involved in DNA binding, the targets and shape of PARylation and the role of PARPs in nucleosome remodelling.

Asunto(s)

RESUMEN

Neointimal hyperplasia after vascular injury is a representative complication of restenosis. Endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) is involved in the pathogenesis of vascular intimal hyperplasia. PARP16, a member of the poly(ADP-ribose) polymerases family, is correlated with the nuclear envelope and the ER. Here, we found that PERK and IRE1α are ADP-ribosylated by PARP16, and this might promote proliferation and migration of smooth muscle cells (SMCs) during the platelet-derived growth factor (PDGF)-BB stimulating. Using chromatin immunoprecipitation coupled with deep sequencing (ChIP-seq) analysis, PARP16 was identified as a novel target gene for histone H3 lysine 4 (H3K4) methyltransferase SMYD3, and SMYD3 could bind to the promoter of Parp16 and increased H3K4me3 level to activate its host gene's transcription, which causes UPR activation and SMC proliferation. Moreover, knockdown either of PARP16 or SMYD3 impeded the ER stress and SMC proliferation. On the contrary, overexpression of PARP16 induced ER stress and SMC proliferation and migration. In vivo depletion of PARP16 attenuated injury-induced neointimal hyperplasia by mediating UPR activation and neointimal SMC proliferation. This study identified SMYD3-PARP16 is a novel signal axis in regulating UPR and neointimal hyperplasia, and targeting this axis has implications in preventing neointimal hyperplasia related diseases.

RESUMEN

Sepsis is not only a threat to the health of individual patients but also presents a serious epidemiological problem. Despite intensive research, modern sepsis therapy remains based primarily on antimicrobial treatment and supporting the functions of failing organs. Finding a cure for sepsis represents a great and as yet unfulfilled need in modern medicine. Research results indicate that the activity of poly (adenosine diphosphate (ADP)-ribose) polymerase (PARP) may play an important role in the inflammatory response and the cellular metabolic disorders found in sepsis. Mechanisms by which PARP-1 may contribute to inflammation and metabolic disorders include effects on the regulation of gene expression, impaired metabolism, cell death, and the release of alarmins. These findings suggest that inhibition of this enzyme may be a promising solution for the treatment of sepsis. In studies using experimental sepsis models, inhibition of PARP-1 has been shown to ameliorate the inflammatory response and increase survival. This action was described, among others, for olaparib, a PARP-1 inhibitor approved for use in oncology. While the results of current research are promising, the use of PARP inhibitors in non-oncological diseases raises some concerns, mainly related to the enzyme's role in deoxyribonucleic acid (DNA) repair. However, the results of studies on experimental models indicate the effectiveness of even short-term PARP-1 inhibition and do not confirm concerns regarding its impact on the integrity of nuclear DNA. Current research presents PARP inhibition as a potential solution for the treatment of sepsis and indicates the need for further research.

RESUMEN

Poly(ADP-ribose) polymerases (PARPs), which transfer either monomer or polymer of ADP-ribose from nicotinamide adenine dinucleotide (NAD+ ) onto target proteins, are required for multiple processes in DNA damage repair, cell cycle, development, and abiotic stress in animals and plants. Here, the uncharacterized rice (Oryza sativa) OsPARP1, which has been predicted to have two alternative OsPARP1 mRNA splicing variants, OsPARP1.1 and OsPARP1.2, was investigated. However, bimolecular fluorescence complementation showed that only OsPARP1.1 interacted with OsPARP3 paralog, suggesting that OsPARP1.1 is a functional protein in rice. OsPARP1 was preferentially expressed in the stamen primordial and pollen grain of mature stamen during flower development. The osparp1 mutant and CRISPR plants were delayed in germination, indicating that defective DNA repair machinery impairs early seed germination. The mutant displayed a normal phenotype during vegetative growth but had a lower seed-setting rate than wild-type plants under normal conditions. Chromosome bridges and DNA fragmentations were detected in male meiocytes at anaphase I to prophase II. After meiosis II, malformed tetrads or tetrads with micronuclei were formed. Meanwhile, the abnormality was also found in embryo sac development. Collectively, these results suggest that OsPARP1 plays an important role in mediating response to DNA damage and gametophyte development, crucial for rice yield in the natural environment.

Asunto(s)