JAK Inhibition Prevents DNA Damage and Apoptosis in Testicular Ischemia-Reperfusion Injury via Modulation of the ATM/ATR/Chk Pathway

Protein profile analysis of Jilin white goose testicles at different stages of the laying cycle by DIA strategy

BACKGROUND

Jilin white goose is an excellent local breed in China, with a high annual egg production and laying eggs mainly from February to July each year. The testis, as the only organ that can produce sperm, can affect the sexual maturity and fecundity of male animals. Its growth and development are affected and regulated by a variety of factors. Proteomics is generally applied to identify and quantify proteins in cells and tissues in order to understand the physiological or pathological changes that occur in tissues or cells under specific conditions. Currently, the female poultry reproductive system has been extensively studied, while few related studies focusing on the regulatory mechanism of the reproductive system of male poultry have been conducted.

RESULTS

A total of 1753 differentially expressed proteins (DEPs) were generated in which there were 594, 391 and 768 different proteins showing differential expression in three stages, Initial of Laying Cycle (ILC), Peak of Laying Cycle (PLC) and End of Laying Cycle (ELC). Furthermore, bioinformatics was used to analyze the DEPs. Gene ontology (GO) enrichment, Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction (PPI) network analysis were adopted. All DEPs were found to be implicated in multiple biological processes and pathways associated with testicular development, such as renin secretion, Lysosomes, SNARE interactions in vesicle trafficking, the p53 signaling pathway and pathways related to metabolism. Additionally, the reliability of transcriptome results was verified by real-time quantitative PCR by selecting the transcript abundance of 6 selected DEPs at the three stages of the laying cycle.

CONCLUSIONS

The funding in this study will provide critical insight into the complex molecular mechanisms and breeding practices underlying the developmental characteristics of testicles in Jilin white goose.

New horizons in lung cancer management through ATR/CHK1 pathway modulation

Lung cancer is the leading cause of cancer-related deaths worldwide. Molecular profiling has contributed to a new classification of lung cancer, driving advancements in research and therapy. The ataxia telangiectasia and rad3/checkpoint kinase 1 (ATR/CHK1) pathway plays a crucial role in maintaining genomic stability, and its activation has been linked to the development of lung cancer, drug resistance and poor prognosis. Clinical and preclinical studies have demonstrated promising results in targeting this pathway. ATR and CHK1 are proteins that collaborate to repair DNA damage caused by radiation or chemotherapy. ATR/CHK1 inhibitors are currently under investigation in preclinical and clinical trials. This article explores the ATR/CHK1 pathway and its potential for treating lung cancer.

The Regulatory Effects of JAK2/STAT3 on Spermatogenesis and the Redox Keap1/Nrf2 Axis in an Animal Model of Testicular Ischemia Reperfusion Injury

The male reproductive system requires the pleiotropic activity of JAK/STAT to maintain its function, especially spermatogenesis. The study aims to investigate the effect of JAK2 signaling on the expression of the Keap1/Nrf2 axis, spermatogenesis, and the Sertoli cells (Sc) junctions in an animal model of testicular ischemia reperfusion injury (tIRI). Testes subjected to tIRI exhibited increased JAK2/STAT3 activity associated with spermatogenic arrest and reduced expression of the Sc junctions. In addition, there was an increased protein expression of Keap1 and decreased Nrf2., which was coupled with the downregulation of gene expression of antioxidant enzymes. Reduced SOD and CAT activities were accompanied by increased lipid peroxidation and protein carbonylation during tIRI. Increased caspase 9 activity and Bax/Bcl2 ratio indicated initiation of apoptosis. Inhibition of JAK2 activity by AG490 maintained the integrity of spermatogenesis and SC junctions, normalized the expression of the Keap1/Nrf2 axis and its downstream antioxidant enzymes, and prevented germ cell apoptosis. The results further emphasized the regulatory role of JAK2/STAT3 on spermatogenesis, Keap1/Nrf2 signaling, and maintenance of the testicular redox balance to combat testicular dysfunction and male infertility.

Sex-Specific Protection of Endothelial Function after Vascular Ischemia/Reperfusion Injury by the Senomorphic Agent Ruxolitinib

Ischemia/reperfusion (I/R)-induced endothelial dysfunction occurs in various cardiovascular disorders. I/R injury is partially driven by the release of cytokines. Known for its use in senotherapy, the JAK inhibitor ruxolitinib is able to block the release of cytokines. We investigated the effect of ruxolitinib on the cytokine release and endothelial-dependent vasorelaxation in an in vitro model of I/R. Aortic segments of C57BL/6J mice (N = 12/group) were divided into three groups: control, in vitro I/R (I/R group), and in vitro I/R with ruxolitinib during ischemic incubation (I/R+Ruxo group). We determined cytokine expression. In organ bath chambers, we investigated the maximal endothelial-dependent relaxation to acetylcholine (R_maxACh) and maximal endothelial-independent relaxation to sodium-nitroprusside (R_maxSNP). R_maxACh was decreased in I/R compared to the control (83.6 ± 2.4 vs. 48.6 ± 3.4%; p < 0.05) and I/R+Ruxo (74.4 ± 2.6 vs. 48.6 ± 3.4%; p < 0.05). R_maxSNP was comparable between all groups. IL-10 was detectable only in I/R+Ruxo. CXCL5, CCL2, CCL3, CCL8, CCL11, ICAM-1, IL-1α, IL-7, TNF-α, and G-CSF were decreased or not detectable in I/R+Ruxo. In I/R+Ruxo, ICAM-1 was reduced in rings only from male mice. Treatment of the aorta from mice during in vitro ischemia with the senomorphic agent ruxolitinib reduces cytokine release and protects the endothelium from I/R-mediated dysfunction.

N-3 PUFA Deficiency from Early Life to Adulthood Exacerbated Susceptibility to Reactive Oxygen Species-Induced Testicular Dysfunction in Adult Mice

Homeostasis of reactive oxygen species is required to maintain sperm maturation and capacitation. Docosahexaenoic acid (DHA) is accumulated in testicles and spermatozoa and has the ability to manipulate the redox status. The effects of dietary n-3 polyunsaturated fatty acid (n-3 PUFA) deficiency from early life to adulthood on the physiological and functional properties of males under the redox imbalance of testicular tissue deserve attention. The consecutive injection of hydrogen peroxide (H₂O₂) and tert-butyl hydroperoxide (t-BHP) for 15 days to induce oxidative stress in testicular tissue was used to elucidate the consequences of testicular n-3 PUFA deficiency. The results indicated that reactive oxygen species treatment in adult male mice with DHA deficiency in the testis could reduce spermatogenesis and disrupt sex hormone production, as well as trigger testicular lipid peroxidation and tissue damage. N-3 PUFA deficiency from early life to adulthood resulted in higher susceptibility to testicular dysfunction in the germinal function of supplying germ cells and the endocrine role of secreting hormones through the mechanism of aggravating mitochondria-mediated apoptosis and destruction of blood testicular barrier under oxidative stress, which might provide a basis for humans to reduce susceptibility to chronic disease and maintain reproductive health in adulthood through dietary interventions of n-3 PUFAs.

Role of ROS/JAK2/STAT3 signaling pathway in di-n-butyl phthalate-induced testosterone synthesis inhibition and antagonism of lycopene

Di-n-butyl phthalate (DBP) causes adverse effects on male reproduction, especially testosterone synthesis inhibition. However, the specific mechanism of DBP-induced testosterone synthesis inhibition and its effective intervention measures of prevention and treatment are scarce presently. Lycopene (LYC) plays beneficial roles in male infertility because of its antioxidant activity. Nevertheless, it is unclear whether LYC could prevent DBP-induced male reproductive toxicity. By in vitro and in vivo investigations, this study demonstrated that DBP activated ROS/JAK2/STAT3 signaling pathway, promoted mitophagy and apoptosis, which in turn inhibited testosterone synthesis. Additionally, another major finding was that LYC supplement could reverse the above change, presenting as the restraint of ROS/JAK2/STAT3 signaling pathway, reduction of mitophagy and apoptosis, and improvement of testosterone synthesis. Our study facilitates deeper understandings of the mechanism in DBP-induced testosterone synthesis inhibition, and identifies LYC as the effective prevention and control strategies for DBP poisoning.

Combined PARP inhibitors and small molecular inhibitors in solid tumor treatment (Review)

With the development of precision medicine, targeted therapy has attracted extensive attention. Poly(ADP‑ribose) polymerase inhibitors (PARPi) are critical clinical drugs designed to induce cell death and are major antitumor targeted agents. However, preclinical and clinical data have revealed the limitations of PARPi monotherapy. Therefore, their combination with other targeted drugs has become a research hotspot in tumor treatment. Recent studies have demonstrated the critical role of small molecular inhibitors in multiple haematological cancers and solid tumors via cellular signalling modulation, exhibiting potential as a combined pharmacotherapy. In the present review, studies focused on small molecular inhibitors targeting the homologous recombination pathway were summarized and clinical trials evaluating the safety and efficacy of combined treatment were discussed.

New Strategies Protecting from Ischemia/Reperfusion

This Special Issue aims to highlight new avenues in the management of Ischemia/Reperfusion (I/R) injury [...].

Radiation-induced PD-L1 expression in tumor and its microenvironment facilitates cancer-immune escape: a narrative review

Background and Objective

Radiotherapy (RT) is one of the fundamental anti-cancer regimens by means of inducing in situ tumor vaccination and driving a systemic anti-tumor immune response. It can affect the tumor microenvironment (TME) components consisting of blood vessels, immunocytes, fibroblasts, and extracellular matrix (ECM), and might subsequently suppress anti-tumor immunity through expression of molecules such as programmed death ligand-1 (PD-L1). Immune checkpoint inhibitors (ICIs), especially anti-programmed cell death 1 (PD-1)/PD-L1 therapies, have been regarded as effective in the reinvigoration of the immune system and another major cancer treatment. Experimentally, combination of RT and ICIs therapy shows a greater synergistic effect than either therapy alone.

Methods

We performed a narrative review of the literature in the PubMed database. The research string comprised various combinations of "radiotherapy", "programmed death-ligand 1", "microenvironment", "exosome", "myeloid cell", "tumor cell", "tumor immunity". The database was searched independently by two authors. A third reviewer mediated any discordance of the results of the two screeners.

Key Content and Findings

RT upregulates PD-L1 expression in tumor cells, tumor-derived exosomes (TEXs), myeloid-derived suppressor cells (MDSCs), and macrophages. The signaling pathways correlated to PD-L1 expression in tumor cells include the DNA damage signaling pathway, epidermal growth factor receptor (EGFR) pathway, interferon gamma (IFN-γ) pathway, cGAS-STING pathway, and JAK/STATs pathway.

Conclusions

PD-L1 upregulation post-RT is found not only in tumor cells but also in the TME and is one of the mechanisms of tumor evasion. Therefore, further studies are necessary to fully comprehend this biological process. Meanwhile, combination of therapies has been shown to be effective, and novel approaches are to be developed as adjuvant to RT and ICIs therapy.

Helicobacter pylori Thioredoxin1 May Play a Highly Pathogenic Role via the IL6/STAT3 Pathway

Background

Recent studies have shown that CagA is considered highly pathogenic to helicobacter pylori (HP) in Western populations. However, in East Asia, CagA positive HP can be up to 90%, but not all patients will lead to gastric cancer. Our research group has found that HP thioredoxin1 (Trx1) may be a marker of high pathogenicity. Here, we investigate whether HP Trx1 exerts high pathogenicity and its internal molecular mechanism.

Materials and Methods

We constructed the coculture system of high-Trx1 HP and low-Trx1 HP strains with gastric epithelial cell lines separately and detected the influence of HP strains. The cells were stained by AM/PI, and the cell's mortality was assessed by fluorescence microscope. The cell's supernatants or precipitates were collected to detect the expression of IL6. In addition, the cell's precipitates were collected, and the expression of p-STAT3 was detected by western blot. Furthermore, the cell's supernatants were collected for detecting the expression of 8-OHDG to investigate the extent of DNA damage.

Results

The high-Trx1 HP can cause higher mortality of GES-1 cells compared with the low-Trx1 HP group (high-Trx1 HP (4.53 ± 0.56) %, low-Trx1 HP (0.39 ± 0.10) %, P < 0.001). The mRNA and protein level of IL-6 in AGS and GES-1 cells were increased during HP infection, and the expression of IL-6 in the High-Trx1 HP group was much higher than the low-Trx1 HP group. Besides, the expression of p-STAT3 was higher in the HP-positive gastric mucosa. And the expression of p-STAT3 in the high-Trx1 HP group was significantly upregulated compared with the low-Trx1 HP group. Furthermore, the expression of 8-OHDG in the high-Trx1 group was much higher than the low-Trx1 group (high-Trx1 HP (5.47 ± 1.73) ng/ml, low-Trx1 HP (2.89 ± 1.72) ng/ml, P < 0.05).

Conclusion

HP Trx1 may play as a marker of high pathogenicity, and the high-Trx1 HP could mediate the pathogenic process of HP infection via the IL6/STAT3 pathway.

Inhibition of PLK3 Attenuates Tubular Epithelial Cell Apoptosis after Renal Ischemia–Reperfusion Injury by Blocking the ATM/P53-Mediated DNA Damage Response

Objective

Renal ischemia–reperfusion (I/R) injury is a major cause of acute kidney injury (AKI) in transplanted kidneys. This study was aimed at exploring the role of PLK3 (polo-like kinase 3) in renal I/R injury, focusing on its relationship with oxidative stress-induced DNA damage and renal tubular epithelial cell (TEC) apoptosis.

Methods

TRAP-seq data from the development dataset GSE52004 and the validation dataset GSE121191 were analyzed using GEO2R. PLK3 overexpression plasmids and targeted silencing siRNAs were used in a model of hypoxia/reoxygenation (H/R) injury, and rAAV-9-PLK3-KD were administered to C57BL/6J mice exposed to I/R injury. The ATM-specific inhibitor KU-60019 was used to block the DNA damage response (DDR). Western blotting was performed to measure DDR- and apoptosis-associated protein expression. Cell viability was measured by CCK-8 reagent, and apoptosis was examined by flow cytometry and TUNEL assay. Furthermore, the fluorescent probes H₂DCFH-DA and DHE were used to measure ROS production in vitro. The MDA level and SOD activity were measured to assess oxidative stress in vivo. KIM-1 staining and Scr and BUN were used to evaluate kidney injury.

Results

The mRNA and protein levels of PLK3 were markedly increased in the H/R injury and I/R injury models. GO terms showed that PLK3 was mainly involved in oxidative stress and DNA damage after renal I/R injury. Overexpression of PLK3 decreased cell viability and increased apoptosis. In contrast, targeted silencing of PLK3 expression decreased the Bax/Bcl-2 ratio by decreasing P53 phosphorylation, thereby reducing TEC apoptosis. Furthermore, KU-60019 reduced PLK3 activation and DDR-induced apoptosis, while overexpression of PLK3 reversed the mitigating effect of KU-60019 on TEC apoptosis. Similarly, rAAV-9-PLK3 KD mice exhibited a lower rate of TEC apoptosis and milder renal damage after I/R injury.

Conclusion

We demonstrate for the first time that PLK3 is involved in oxidative stress-induced DNA damage and TEC apoptosis in renal I/R injury. Inhibition of PLK3 attenuates TEC apoptosis after I/R injury by blocking the ATM/P53-mediated DDR. Therefore, PLK3 may serve as a potential therapeutic target for ischemic AKI.