Receptor Protein Levels Research Articles

Oral exposure to phenanthrene during gestation disorders endocrine and spermatogenesis in F1 adult male mice

Phenanthrene (Phe), a typical low-molecular-weight polycyclic aromatic hydrocarbon (PAH) of three benzene rings, is one of the most abundant PAHs detected in daily diets. Pregnant women and infants are at great risk of Phe exposure. In the present study, Phe was administered to pregnant mice at a dose of 0, 60, or 600 μg/kg body weight six times, and the F1 male mice showed significant reproductive disorders: the testicular weight and testis somatic index were significantly reduced; the levels of serum testosterone, GnRH and SHBG were increased, while the FSH levels were reduced; histological analysis showed that the amount of Sertoli cells and primary spermatocytes in seminiferous tubules was increased, while the amount of secondary spermatocytes and spermatids were decreased in Phe groups. The protein levels of PCNA and androgen receptor were reduced. Differently expressed genes in the testis screened by RNA sequence were enriched in antioxidant capacity, reproduction et al.. Further biochemical tests confirmed that the antioxidant capacity in the F1 testis was significantly inhibited by treatment with Phe during pregnancy. Those results suggested that gestational Phe exposure disordered hypothalamic-pituitary-gonadal (HPG) hormones on the one hand, and on the other hand reduced testicular antioxidant capacity and further arrested cell cycle in F1 adult male mice, which co-caused the inhibition of spermatogenesis.

Novel mechanisms of Anshen Dingzhi prescription against PTSD: Inhibiting DCC to modulate synaptic function and inflammatory responses

Ethnopharmacological relevanceAnshen Dingzhi prescription (ADP), documented in “Yi Xue Xin Wu”, is a famous prescription for treating panic-related mental disorders such as post-traumatic stress disorder (PTSD). However, the underlying mechanism remains unclear. Aim of the studyThis study aimed to investigate the mechanisms by which ADP intervened in PTSD-like behaviors. MethodsA mouse model of single prolonged stress (SPS) was established to evaluate the ameliorative effects and mechanisms of ADP on PTSD. Behavioral tests were used to assess PTSD-like behaviors in mice; transmission electron microscopy was used to observe changes in the ultrastructure of hippocampal synapses, and western blot, immunofluorescence, and ELISA were used to detect the expression of hippocampal deleted in colorectal cancer (DCC) and downstream Ras-related C3 botulinum toxin substrate 1 (Rac1) - P21-activated kinase 1 (PAK1) signal, as well as levels of synaptic proteins and inflammatory factors. Molecular docking technology simulated the binding of potential brain-penetrating components of ADP to DCC. ResultsSPS induced PTSD-like behaviors in mice and increased expression of hippocampal netrin-1 (NT-1) and DCC on the 14th day post-modeling, with concurrent elevation in serum NT-1 levels. Simultaneously, SPS also decreased p-Rac1 level and increased p-PAK1 level, the down-stream molecules of DCC. Lentiviral overexpression of DCC induced or exacerbated PTSD-like behaviors in control and SPS mice, respectively, whereas neutralization antibody against NT-1 reduced DCC activation and ameliorated PTSD-like behaviors in SPS mice. Interestingly, downstream Rac1-PAK1 signal was altered according to DCC expression. Moreover, DCC overexpression down-regulated N-methyl-d-aspartate (NMDA) receptor 2A (GluN2A) and postsynaptic density 95 (PSD95), up-regulated NMDA receptor 2B (GluN2B) and increased neuroinflammatory responses. Administration of ADP (36.8 mg/kg) improved PTSD-like behaviors in the SPS mice, suppressed hippocampal DCC, and downstream Rac1-PAK1 signal, upregulated GluN2A and PSD95, downregulated GluN2B, and reduced levels of inflammatory factors NOD-like receptor protein 3 (NLRP3), nuclear factor kappa-B (NF-κB) and interleukin-6 (IL-6). Importantly, DCC overexpression could also reduce the ameliorative effect of ADP on PTSD. Additionally, DCC demonstrated a favorable molecular docking pattern with the potential brain-penetrating components of ADP, further suggesting DCC as a potential target of ADP. ConclusionOur data indicate that DCC is a key target for the regulation of synaptic function and inflammatory response in the onset of PTSD, and ADP likely reduces DCC to prevent PTSD via modulating downstream Rac1-PAK1 pathway. This study provides a novel mechanism for the onset of PTSD and warrants the clinical application of ADP.

Dynamic modulation of nodulation factor receptor levels by phosphorylation-mediated functional switch of a RING-type E3 ligase during legume nodulation

The precise control of receptor levels is crucial for initiating cellular signaling transduction in response to specific ligands; however, such mechanisms regulating nodulation factor (NF) receptor (NFR)-mediated perception of NFs to establish symbiosis remain unclear. In this study, we unveil the pivotal role of the NFR-interacting RING-type E3 ligase 1 (NIRE1) in regulating NFR1/NFR5 homeostasis to optimize rhizobial infection and nodule development in Lotus japonicus. We demonstrated that NIRE1 has a dual function in this regulatory process. It associates with both NFR1 and NFR5, facilitating their degradation through K48-linked polyubiquitination before rhizobial inoculation. However, following rhizobial inoculation, NFR1 phosphorylates NIRE1 at a conserved residue, Tyr-109, inducing a functional switch in NIRE1, which enables NIRE1 to mediate K63-linked polyubiquitination, thereby stabilizing NFR1/NFR5 in infected root cells. The introduction of phospho-dead NIRE1Y109F leads to delayed nodule development, underscoring the significance of phosphorylation at Tyr-109 in orchestrating symbiotic processes. Conversely, expression of the phospho-mimic NIRE1Y109E results in the formation of spontaneous nodules in L. japonicus, further emphasizing the critical role of the phosphorylation-dependent functional switch in NIRE1. In summary, these findings uncover a fine-tuned symbiotic mechanism that a single E3 ligase could undergo a phosphorylation-dependent functional switch to dynamically and precisely regulate NF receptor protein levels.

Cold Acclimation and Deacclimation of Winter Oilseed Rape, with Special Attention Being Paid to the Role of Brassinosteroids.

Winter plants acclimate to frost mainly during the autumn months, through the process of cold acclimation. Global climate change is causing changes in weather patterns such as the occurrence of warmer periods during late autumn or in winter. An increase in temperature after cold acclimation can decrease frost tolerance, which is particularly dangerous for winter crops. The aim of this study was to investigate the role of brassinosteroids (BRs) and BR analogues as protective agents against the negative results of deacclimation. Plants were cold-acclimated (3 weeks, 4 °C) and deacclimated (1 week, 16/9 °C d/n). Deacclimation generally reversed the cold-induced changes in the level of the putative brassinosteroid receptor protein (BRI1), the expression of BR-induced COR, and the expression of SERK1, which is involved in BR signal transduction. The deacclimation-induced decrease in frost tolerance in oilseed rape could to some extent be limited by applying steroid regulators. The deacclimation in plants could be detected using non-invasive measurements such as leaf reflectance, chlorophyll a fluorescence, and gas exchange monitoring.

Lycopene in Combination with Insulin Triggers Antioxidant Defenses and Increases the Expression of Components That Detoxify Advanced Glycation Products in Kidneys of Diabetic Rats.

Biochemical events provoked by oxidative stress and advanced glycation may be inhibited by combining natural bioactives with classic therapeutic agents, which arise as strategies to mitigate diabetic complications. The aim of this study was to investigate whether lycopene combined with a reduced insulin dose is able to control glycemia and to oppose glycoxidative stress in kidneys of diabetic rats. Streptozotocin-induced diabetic rats were treated with 45 mg/kg lycopene + 1 U/day insulin for 30 days. The study assessed glycemia, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma. Superoxide dismutase (SOD) and catalase (CAT) activities and the protein levels of advanced glycation end-product receptor 1 (AGE-R1) and glyoxalase-1 (GLO-1) in the kidneys were also investigated. An effective glycemic control was achieved with lycopene plus insulin, which may be attributed to improvements in insulin sensitivity. The combined therapy decreased the dyslipidemia and increased the PON-1 activity. In the kidneys, lycopene plus insulin increased the activities of SOD and CAT and the levels of AGE-R1 and GLO-1, which may be contributing to the antialbuminuric effect. These findings demonstrate that lycopene may aggregate favorable effects to insulin against diabetic complications resulting from glycoxidative stress.

Sulfate glycosaminoglycan from swim bladder exerts immunomodulatory potential on macrophages via toll-like receptor 4 mediated NF-κB signaling pathways

This study explored the immunomodulatory impact and potential mechanisms on macrophages RAW264.7 using a purified macromolecular sulfate glycosaminoglycan (SBSG) from the swim bladder, whose structure was similar to chondroitin sulfate A. The results showed that SBSG at 0.25–1 mg/mL increased the viability and phagocytosis of RAW264.7 cells. Meanwhile, SBSG promoted the secretion of tumor necrosis factor α (TNF-α), interleukin 10 (IL-10), and nitric oxide (NO), as well as the production of reactive oxygen species (ROS). According to the RT-PCR and Western blot data, SBSG activated TLR4-nuclear factor kappa B (NF-κB) signaling pathways, which decreased the relative mRNA and protein levels of Toll-like receptor 4 (TLR4), IκB kinase β (IKKβ), NF-κB p65, and p-NF-κB p65. The molecular docking and molecular dynamic simulation findings revealed that the main binding force between TLR4 and SBSG was conventional hydrogen bond interaction, resulting in more stable ligand receptor complexes. In summary, SBSG exhibits significant immunomodulatory potential, similar to chondroitin sulfate C. The underlying molecular mechanism involved the binding of SBSG through hydrogen bonding to TLR4 receptors, triggering the NF-κB signaling pathway to downregulate the expression of related genes and proteins. This, in turn, regulated the secretion of various cytokines that were mediated by macrophages to exert the immunity of the body.

Abstract PO4-03-08: Enhanced Assessment of Clinical Behavior of TNBC and TPBC using Quantified Levels of HER2, Estrogen and Progestin Receptor Proteins and Expression of Their Cognate Genes

Abstract Background: Renewed interest in clinical relevance of low-HER2 protein in breast cancer management prompted a retrospective investigation of a unique de-identified Database of quantified biomarkers associated with patient outcomes. Currently, IHC of ER, PR and HER2 proteins provides semi-quantitative results, at times complicated by variation in methods and interpretation (cf. ASCO/CAP Guidelines). Our goal was to ascertain relationships of these clinical analytes to predict cancer relapse when quantified for protein products and cognate gene expression. Methods: Database contained 2756 quantified HER2 results by ELISA (Oncogene Sciences) or by EIA (Triton Diagnostics) of which 198 patients had associated clinical outcomes. No definition of HER2-low has been accepted for IHC, although > 50% of biopsies may be categorized as HER2-low (cf. ASCP CE Programs). Microarray results obtained for ~ 22,000 genes using RNA purified from LCM-procured carcinoma cells of 247 primary breast biopsies were analyzed. ESR1, PGR and ERBB2 gene expression levels in 276 biopsies had been validated by RTqPCR. To assess distribution and dispersion of HER2 protein, cumulative relative frequency distribution analyses were employed, focusing on cut-offs within interquartile range. Permutations and combinations of the 3 biomarkers based on IHC definitions (cf. ASCO/CAP Guidelines) were examined. Tertiles and quartiles of data sets were used to explore association between biomarker levels and clinical outcomes. Box plots depicted protein and gene expression levels, Progression-Free Survival (PFS), or Overall Survival (OS) across ER/PR/HER2 categories and compared differences using a Kruskal-Wallis ANOVA Rank Test. Cox regressions were used to contrast hazard ratios among the ER/PR/HER2 groups. Kaplan-Meier plots visualized survival rates among groups and a log-rank test detected statistical discrepancies. We investigated differences between groups for categorical variables using chi-squared tests (Fisher's exact test for non-normally distributed data), while for ordinal variables, ANOVA tests were used (Kruskal-Wallis for non-normally distributed data). Categorical variables were summarized as count (%), and ordinal variables were summarized as median [IQR]. Analyses were performed using R version 4.2.2 (Innocent and Trusting). Results: Neither quantified ER or PR alone nor ER/PR collectively were related to HER2 oncoprotein levels. Influence of menopausal status on biopsy biomarker profiles was investigated. With a median cutoff for HER2 protein, patients with ER+/PR+/HER2+ (TPBC) exhibited increased OS, whereas those with TNBC had decreased OS, of 8 combinations possible. Using tertiles and quartiles, TPBC was exhibited by 34-37% of specimens compared to TNBC, which represented 9.1-12.7% of biopsies when biomarker proteins were quantified. After qPCR data were stratified by ER/PR/HER2 status with a 50% quantile cut for HER2, 39% were TPBC and 10% were TNBC. Using microarray data with the same cutoffs, only 14% were TPBC and 17% were TNBC. Once TPBC were identified by either microarray or by qPCR, increased ESR1, PGR and ERBB2 expression collectively was associated with increased PFS and OS of patients. In general, biopsies that were TNBC or other combinations of biomarker’s gene expression correlated with poorer prognosis and overall survival. Conclusions: Quantifying levels of ER, PR and HER2 proteins as well as of ESR1, PGR and ERBB2 expression were correlated with prediction of clinical outcomes of TNBC, TPBC and patients with other biomarker subsets. Results support quantitative assessment of these biomarkers in biopsies to assess utility of the HER2-low type in personalizing breast cancer management and prediction of risk of relapse. Citation Format: James Wittliff, Michael Daniels. Enhanced Assessment of Clinical Behavior of TNBC and TPBC using Quantified Levels of HER2, Estrogen and Progestin Receptor Proteins and Expression of Their Cognate Genes [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-03-08.

SiRNA Mediated Downregulation of RhoA Expression Reduces Oxidative Induced Apoptosis in Retinal Ganglion Cells.

Glaucoma is the second leading cause of blindness. Apoptosis of retinal ganglion cells (RGCs) is an important mechanism of glaucomatous optic injury. Rho kinase expression is significantly increased in apoptotic RGCs. This study aimed to investigate the role of RhoA, a Rho GTPase, on the survival of RGCs and further to explore its potential therapeutic applications. RGCs were treated with siRhoA for 24 hours in vitro. Knockdown of RhoA was confirmed with quantitative RT-PCR. Oxidative stress was induced by treating the RGCs with 200 μM of H2O2 for 1 hour, and apoptosis of RGCs was quantified with TUNEL assay in situ, and with flow cytometry. The mRNA expression levels of RhoA, Nogo receptor, caspase 3 and Bcl-2 were evaluated by quantitative RT-PCR, and the protein levels of RhoA, ROCK1, ROCK2, Nogo receptor, caspase 3 and Bcl-2 were evaluated by Western blot. We found siRhoA treatment efficiently downregulated the expression of RhoA in RGCs and protected against H2O2-induced injury in RGCs in vitro. Apoptosis of RGC cells under oxidative stress was quantified in situ using TUNEL assay and confirmed with flow cytometry (FCM). With the knockdown of RhoA, the expression of ROCK1, ROCK2, Nogo Receptor, Casepase-3 were decreased, while the expression of Bcl-2 was increased in both mRNA and protein level. Our data indicated that siRhoA prevented H2O2-induced apoptosis in RGC cells by modulating the RhoA/ROCK pathway. The results suggested that siRhoA may exert potentially effective neuroprotection for RGCs by reducing injury.

Exploring the potential of pomegranate (Punica granatum) peel extract and punicalagin as novel anti-hypercholesterolemic agents

Background: Hypercholesterolemia, characterized by elevated low-density lipoprotein (LDL) cholesterol levels, is a significant risk factor for cardiovascular diseases. Familial and behavioral factors contribute to its onset, and while lifestyle changes offer some benefits, medical interventions are essential to manage this condition effectively. Statins, the primary medications used to lower LDL cholesterol, have limitations, including the unintended upregulation of proprotein convertase subtilisin/kexin type 9 (PCSK9). Therefore, exploring alternative approaches to enhance LDL receptor expression while targeting PCSK9 is crucial, with herbal medicine showing promise in this endeavor. Objective: This study investigates the potential of pomegranate peel extract and punicalagin, a key pomegranate component, in lowering LDL cholesterol in HepG2 cells. The research explores their effects on LDL receptor (LDLR) expression, LDL uptake, and proprotein convertase subtilisin/kexin type 9 (PCSK9) gene expression. Methods: HepG2 cells were treated with different concentrations of pomegranate peel extract (37.5, 75, 150, and 300 μg/ml) and punicalagin (12.5, 25, 50, and 100 μg/ml). Next, the viability of HepG2 cells, the protein levels of LDL receptors and LDL uptake, and the expression levels of PCSK9 were measured. Results: Pomegranate peel extract (37.5, 75, 150, and 300 μg/ml) and punicalagin (12.5, 25, 50, and 100 μg/ml) did not exhibit significant cytotoxicity and significantly increased LDLR protein levels (P-value= 0.00, after 24 hours) and LDL cholesterol uptake (P-value= 0.00, after 24 hours). Furthermore, they exhibited a dose-dependent reduction in the expression of PCSK9 (pomegranate: P-value= 0.01; punicalagin: P-value= 0.00). Conclusion: These findings suggest that pomegranate peel extract and punicalagin have the potential to serve as effective agents in managing hypercholesterolemia by enhancing LDL receptor expression and reducing PCSK9 expression in HepG2 cells. Further research is required to explore their effects on transcription factors and PCSK9 function. Keywords: Pomegranate; Punicalagin; HepG2 cell; LDL; Cardiovascular; Punica granatum

PM2.5 exposure upregulates pro-inflammatory protein expression in human microglial cells via oxidant stress and TLR4/NF-κB pathway

Exposure to ambient PM2.5 is associated with neurodegenerative disorders, in which microglia activation plays a critical role. Thus far, the underlying mechanisms for PM2.5-induced microglia activation have not been well elucidated. In this study, a human microglial cell line (HMC3) was used as the in vitro model to examine the inflammatory effect (hall marker of microglia activation) of PM2.5 and regulatory pathways. The expression of inflammatory mediators including interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) as well as the brain derived neurotrophic factor (BDNF) were determined by ELISA and/or real-time PCR, respectively. Flow cytometry was used to measure the production of intracellular reactive oxygen species (ROS). Western blot was used to measure protein levels of Toll-like receptor 4 (TLR4), NF-κB inhibitor α (IκBα) and COX-2. It was shown that PM2.5 stimulation increased IL-6 and COX-2 expression but decreased BDNF expression in a dose-dependent manner. Further studies showed that PM2.5 triggered the formation of ROS and pre-treatment with the ROS scavenger acetylcysteine (NAC) significantly suppressed PM2.5-induced IL-6 and COX-2 expression. Moreover, the nuclear factor kappa B (NF-κB) inhibitor BAY11–7085 or the TLR4 neutralizing antibody markedly blocked PM2.5-induced IL-6 and COX-2 expression. However, NAC or BAY11–7085 exhibited minimal effect on PM2.5-induced BDNF down-regulation. In addition, pre-treatment with BAY11–7085 or TLR4 neutralizing antibody reduced ROS production induced by PM2.5, and NAC pre-treatment inhibited TLR4 expression and NF-κB activation induced by PM2.5. Collectively, PM2.5 treatment induced IL-6 and COX-2 but suppressed BDNF expression. PM2.5-induced IL-6 and COX-2 expression was mediated by interactive oxidative stress and TLR4/NF-κB pathway.

The Essential Role of PGF2α/PTGFR in Molding Endometrial Breakdown and Vascular Dynamics, Regulated by HIF-1α in a Mouse Menstrual-like Model.

In women of childbearing age, extensive decidualization, shedding and remodeling of the endometrium during the menstrual cycle are fundamental for successful pregnancy. The role of prostaglandins (PGs) in menstruation has long been proposed in humans, and the rate-limiting enzyme cyclooxygenase was shown to play a key role in endometrial breakdown and shedding in a mouse menstrual-like model in our previous study. However, the specific types of PGs involved and their respective roles remain unclear. Therefore, our objective was to investigate the mechanism through which PGs regulate endometrial disintegration. In this study, the microscopy was observed by HE; the protein levels of prostaglandins E1 (PGE1), prostaglandins E2 (PGE2), prostaglandin F2α (PGF2α) and Prostaglandin I2 (PGI2) were detected by ELISA; the mRNA level of Pfgfr2, Vascular Endothelial Growth Factor(Vegf), Angiostatin and Hypoxia inducible factor-1α (Hif1α) were examined by real-time PCR; PTGFR Receptor (PTGFR), VEGF, Angiostatin and HIF-1α protein levels were investigated by western blotting; the locations of protein were observed by Immunohistochemistry; HIF-1α binding PTGFR promoter was detected by Chromatin Immunoprecipitation (ChIP) and real-time PCR. We found that the concentrations of PGE1, PGE2, and PGF2α all increased significantly during this process. Furthermore, Ptgfr mRNA increased soon after Progesterone (P4) withdrawal, and PTGFR protein levels increased significantly during abundant endometrial breakdown and shedding processes. PTGFR inhibitors AL8810 significantly suppressed endometrial breakdown and shedding, promoted Angiostatin expression, and reduced VEGF-A expressions and vascular permeability. And HIF-1α and PTGFR were mainly located in the luminal/gland epithelium, vascular endothelium, and pre-decidual zone. Interestingly, HIF-1α directly bound to Ptgfr promoter. Moreover, a HIF-1α inhibitor 2-methoxyestradiol (2ME) significantly reduced PTGFR expression and suppressed endometrial breakdown which was in accord with PTGFR inhibitor's effect. Similar changes occurred in human stromal cells relevant to menstruation in vitro. Our study provides evidence that PGF2α/PTGFR plays a vital role in endometrial breakdown via vascular changes that are regulated by HIF-1α during menstruation.

Insulin-like growth factor 1 knockdown attenuates high glucose-induced podocyte injury by promoting the JAK2/STAT signalling-mediated autophagy.

Podocyte injury plays a crucial role in the development of diabetic nephropathy (DN). A high serum level of insulin-like growth factor 1 (IGF-1) has been observed in patients with DN. This paper is to study the role and mechanism of IGF-1 in high glucose (HG)-induced podocyte injury. Mouse podocytes MPC-5 were treated with HG to establish a DN model in vitro. db/db diabetic mice and db/m nondiabetic mice were used to evaluate the IGF-1 role in vivo. Western blotting was used for measuring protein levels of IGF-1 receptor, Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway-related markers, podocyte markers podocin and nephrin, apoptosis- and autophagy-related markers in MPC-5 cells. Immunofluorescence staining was implemented for measuring the expression of nephrin and the autophagy marker LC3. Flow cytometry was used for detecting podocyte apoptosis. IGF-1 expression was increased in HG-stimulated MPC-5 cells and the kidney of db/db diabetic mice compared with corresponding controls. Knocking down IGF-1 downregulated IGF-1R and inhibited JAK2/STAT signalling pathway in HG-treated MPC-5 cells and db/db diabetic mice. IGF-1 silencing attenuated HG-induced podocyte injury, apoptosis and reduction in autophagy. Activating the JAK2/STAT signalling pathway or inhibiting autophagy reversed the effects of IGF-1 silencing on HG-treated MPC-5 cells. Knocking down IGF-1 alleviates HG-induced podocyte injury and apoptosis by inactivating the JAK2/STAT signalling pathway and enhancing autophagy.

DPP-4 inhibitors sitagliptin and PF-00734,200 mitigate dopaminergic neurodegeneration, neuroinflammation and behavioral impairment in the rat 6-OHDA model of Parkinson’s disease

Epidemiological studies report an elevated risk of Parkinson's disease (PD) in patients with type 2 diabetes mellitus (T2DM) that is mitigated in those prescribed dipeptidyl peptidase 4 (DPP-4) inhibitors. With an objective to characterize clinically translatable doses of DPP-4 inhibitors (gliptins) in a well-characterized PD rodent model, sitagliptin, PF-00734,200 or vehicle were orally administered to rats initiated either 7-days before or 7-days after unilateral medial forebrain bundle 6-hydroxydopamine (6-OHDA) lesioning. Measures of dopaminergic cell viability, dopamine content, neuroinflammation and neurogenesis were evaluated thereafter in ipsi- and contralateral brain. Plasma and brain incretin and DPP-4 activity levels were quantified. Furthermore, brain incretin receptor levels were age-dependently evaluated in rodents, in 6-OHDA challenged animals and human subjects with/without PD. Cellular studies evaluated neurotrophic/neuroprotective actions of combined incretin administration. Pre-treatment with oral sitagliptin or PF-00734,200 reduced methamphetamine (meth)-induced rotation post-lesioning and dopaminergic degeneration in lesioned substantia nigra pars compacta (SNc) and striatum. Direct intracerebroventricular gliptin administration lacked neuroprotective actions, indicating that systemic incretin-mediated mechanisms underpin gliptin-induced favorable brain effects. Post-treatment with a threefold higher oral gliptin dose, likewise, mitigated meth-induced rotation, dopaminergic neurodegeneration and neuroinflammation, and augmented neurogenesis. These gliptin-induced actions associated with 70–80% plasma and 20–30% brain DPP-4 inhibition, and elevated plasma and brain incretin levels. Brain incretin receptor protein levels were age-dependently maintained in rodents, preserved in rats challenged with 6-OHDA, and in humans with PD. Combined GLP-1 and GIP receptor activation in neuronal cultures resulted in neurotrophic/neuroprotective actions superior to single agonists alone. In conclusion, these studies support further evaluation of the repurposing of clinically approved gliptins as a treatment strategy for PD.

Long-Term Impact of Diffuse Traumatic Brain Injury on Neuroinflammation and Catecholaminergic Signaling: Potential Relevance for Parkinson's Disease Risk.

Traumatic brain injury (TBI) is associated with an increased risk of developing Parkinson's disease (PD), though the exact mechanisms remain unclear. TBI triggers acute neuroinflammation and catecholamine dysfunction post-injury, both implicated in PD pathophysiology. The long-term impact on these pathways following TBI, however, remains uncertain. In this study, male Sprague-Dawley rats underwent sham surgery or Marmarou's impact acceleration model to induce varying TBI severities: single mild TBI (mTBI), repetitive mild TBI (rmTBI), or moderate-severe TBI (msTBI). At 12 months post-injury, astrocyte reactivity (GFAP) and microglial levels (IBA1) were assessed in the striatum (STR), substantia nigra (SN), and prefrontal cortex (PFC) using immunohistochemistry. Key enzymes and receptors involved in catecholaminergic transmission were measured via Western blot within the same regions. Minimal changes in these markers were observed, regardless of initial injury severity. Following mTBI, elevated protein levels of dopamine D1 receptors (DRD1) were noted in the PFC, while msTBI resulted in increased alpha-2A adrenoceptors (ADRA2A) in the STR and decreased dopamine beta-hydroxylase (DβH) in the SN. Neuroinflammatory changes were subtle, with a reduced number of GFAP+ cells in the SN following msTBI. However, considering the potential for neurodegenerative outcomes to manifest decades after injury, longer post-injury intervals may be necessary to observe PD-relevant alterations within these systems.

Abstract 5343: Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice

Abstract Gut microbes have the potential to be either promoters or inhibitors of cancer. Use of antibiotics during cancer therapy can lead to dysbiosis, which may affect treatment outcomes. Here, we examine the effects of broad-spectrum antibiotics on cancer progression in mice with Pten-null castration resistant prostate cancer (CRPC). After five or eight weeks, orchiectomized conditional Pten-null knockout (KO) mice aged 50 and 90 weeks were given two biweekly cycles of a broad-spectrum antibody cocktail (BSAbx), respectively. The effects of BSAbx on tumor burden were compared, and molecular and immunological responses were analyzed by quantitative IHC (qIHC) and qRt-PCR at week four after antibiotic treatment. BSAbx treatment resulted in tumor burdens of 1.2 and 2.4-fold higher than in control mice in mice aged 50 and 90 weeks, respectively. qIHC analysis of KI67 showed increased proliferation in stromal and cancer cells. Additionally, androgen receptor (AR) protein and gene expression levels of Ar and Ar target genes (Fkbp5, Tmprss2, and Timp4) were elevated in tumors of BSAbx-treated mice. Restoring gut microbiota by fecal microbiota transplantation (FMT) from KO mice CRPC after BSAbx restored AR transcriptional activity to basal levels and lessened tumor growth. FMT from non-castrated KO with castration-naïve prostate cancer or heathy wildtype mice further reduced AR Transcriptional activity. Moreover, altering the gut microbiota of CRPC mice with FMT from heathy mice resulted in a tendency for lower tumor burden, 21% reduction versus control mice. Immunologically, BSAbx treatment resulted in decreased CD11b+/GR1+ cells in tumors and were associated with decreased interferon-gamma (IFN-gamma), dendritic cell functions and T cell-mediated cytotoxicity gene signatures. Mice that received FMT form health mice showed enhanced T cell mediated immunity as demonstrated by higher IFN-gamma signatures and tumor abundances of CD8+ T cells expression IFN-gamma, TNF-alpha and the cytotoxic granule granzyme B. Our study shows that broad spectrum antibiotics caused dysbiosis and promoted prostate cancer growth in mice with Pten-null prostate cancer. The effects were partly mediated through the upregulation of AR signaling and the impairment of neutrophil and T cell-mediated immune responses in tumors. Citation Format: Marco A. De Velasco, Yurie Kura, Kazuko Sakai, Mitsuhisa Nishimoto, Yasunori Mori, Kazuhiro Yoshimura, Kazutoshi Fujita, Kazuto Nishio, Hirotsugu Uemura. Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5343.

Abstract 3013: Alzheimer’s-linked gene BIN1: Unraveling its unexpected role as a tumor suppressor in prostate cancer and influence on androgen receptor signaling

Abstract Androgen-receptor signaling inhibitors (ARSI) have been shown to significantly alter the natural history of castration-resistant PCa (CRPC). Unfortunately, resistance to ARSIs is inevitable. Unraveling the underlying mechanisms to identify potential therapeutic interventions to treat these lethal tumors has become a critical challenge in the post-ARSI era. Recent genomic sequencing has revealed a subclass of PCa harboring deletion of bridging integrator-1 (BIN1) and is associated with increased AR activity. Notably, BIN1 deletion frequently co-occurs with SPOP mutation and deletion of SPOPL, collectively suggesting BIN1 may function as tumor suppressor. To elucidate the role of BIN1 in prostate cells, we generated a prostate-specific BIN1 knockout murine model (PB-CreBIN1FL/FL). This model revealed increased prostate mass at 6 months of age, accompanied by increased cell proliferation. We next crossed this strain to SPOP mutant (SPOPF133V) model to generate a prostate specific BIN1 knockout, SPOP mutant model (PB-CreSPOPF133VBIN1FL/FL) and found increased proliferation and greater prostate mass compared to animals harboring SPOP mutation or BIN1 deletion alone. Next, we generated a doxycycline inducible BIN1 overexpressing PCa model (22Rv1BINOE) to evaluate AR signaling in vitro. We found that overexpression of BIN1 modestly reduced prostate cancer cell proliferation but profoundly suppressed androgen receptor protein level. To evaluate the transcriptional activity of AR and ARv7, we also utilized a luciferase reporter system harboring ARE consensus sequences found in the KLK3 gene (AR-FL target) promoter or in the EDN2 gene (ARv7 target) promoter, respectively. These reporter assays illustrated suppression of both AR-FL and AR-v7 driven gene transcriptional program upon BIN1 overexpression. Co-expression of both BIN1 and SPOPwt showed a synergistic knockdown of AR activity, while SPOPmut did not show this effect. These observations were further confirmed using global RNAseq. The RNAseq analysis also showed downregulation of several AR pathways as well as gene sets associated with cancer progression and metastasis. Interestingly, the RNAseq data showed downregulation of genes that are normally upregulated after SPOP mutation, further suggesting a synergistic role between SPOP and BIN1. Citation Format: Collin McColl, Darlene Skapura, Elisa Ruiz Echartea, Jenny Deng, Aleksandra Rusin, Jinna Shin, Alexey Tyryshkin, Christel Davis, Erik Ehil, Salma Kaochar. Alzheimer’s-linked gene BIN1: Unraveling its unexpected role as a tumor suppressor in prostate cancer and influence on androgen receptor signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3013.

Piperine attenuates hepatic ischemia/reperfusion injury via suppressing the TLR4 signaling cascade in mice

Piperine, the major active substance in black pepper, has been shown to have anti-inflammatory and antioxidant effects in several ischemic diseases. However, the role of piperine in hepatic ischemia/reperfusion injury (HIRI) and its underlying mechanisms remain unclear. In this study, the mice were administered piperine (30 mg/kg) intragastric administration before surgery. After 24 h of hepatic ischemia-reperfusion, liver histopathological evaluation, serum transaminase measurements, and TUNEL analysis were performed. The infiltration of inflammatory cells and production of inflammatory mediators in the liver tissue were determined by immunofluorescence and immunohistochemical staining. The protein levels of toll-like receptor 4 (TLR4) and related proteins such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin-1 receptor-associated kinase 1 (IRAK1), p65, and p38 were detected by western blotting. The results showed that plasma aminotransferase (ALT), aspartate aminotransferase (AST), hepatocyte apoptosis, oxidative stress, and inflammatory cell infiltration significantly increased in HIRI mice. Piperine pretreatment notably repaired liver function, improved the histopathology and apoptosis of liver cells, alleviated oxidative stress injury, and reduced inflammatory cell infiltration. Further analysis showed that piperine attenuated tumor necrosis factor-a (TNF-α) and interleukin 6 (IL-6) production and reduced TLR4 activation and phosphorylation of IRAK1, p38, and NF-κB in HIRI. Piperine has a protective effect against HIRI through the TLR4/IRAK1/NF-κB signaling pathway and may be a safer option for future clinical treatment and prevention of ischemia-related diseases.

D-Pinitol mitigates post-traumatic stress disorder-like behaviors induced by single prolonged stress in mice through mineralocorticoid receptor antagonism

Post-traumatic stress disorder (PTSD) is a mental illness that can occur in individuals who have experienced trauma. Current treatments for PTSD, typically serotonin reuptake inhibitors, have limited effectiveness for patients and often cause serious adverse effects. Therefore, a novel class of treatment with better pharmacological profile is necessary. D-Pinitol has been reported to be effective for depression and anxiety disorders, but there are no reports associated with PTSD. In the present study, we investigated the effects of D-pinitol in a mouse model of PTSD induced by a single prolonged stress (SPS) protocol. We examined the therapeutic effects of D-pinitol on emotional and cognitive impairments in the SPS mouse model. We also investigated the effects of D-pinitol on fear memory formation. Mineralocorticoid receptor transactivation assay, Western blot, and quantitative PCR were employed to investigate how D-pinitol exerts its pharmacological activities. D-Pinitol ameliorated PTSD-like behaviors in a SPS mouse model. D-Pinitol also normalized the increased mRNA expression levels and protein levels of the mineralocorticoid receptor in the amygdala. A mineralocorticoid receptor agonist reversed the effects of D-pinitol on fear extinction and recall, and the antagonistic property of D-pinitol against the mineralocorticoid receptor was confirmed in vitro. Our findings suggest that D-pinitol could serve as a potential therapeutic agent for PTSD due to its antagonistic effect on the mineralocorticoid receptor.

Chronic exposure to low levels of phenanthrene induces histological damage and carcinogenic risk in the uterus of female mice.

Phenanthrene (Phe), a polycyclic aromatic hydrocarbon with low molecular weight, is detected in the environment at high frequency. To study the toxic effects of Phe on the uterine structure and function, female Kunming mice were exposed to Phe (0.05, 0.5, 5ng/mL) for 270days by drinking water. Pathological alterations and their action pathways were analyzed using immunohistochemical and biomolecular technology. Phe significantly increased the percentage of blood vessel area, the number of endometrial neutrophils (indicating the occurrence of inflammation), collagen deposition (indicating fibrosis), and the percentage of Ki-67-positive cells (indicating carcinogenesis) in the uterus. Transcriptome sequencing identified differentially expressed genes that were mainly enriched in some signaling pathways, including inflammation and carcinogenesis, suggesting a carcinogenic risk in the Phe-exposed uterus. Elevated serum estrogen levels and decreased progesterone levels exhibited a disturbance of steroid hormone balance, which might be related to uterine damage. Upregulated protein levels of uterine androgen receptor and estrogen receptor α were linked to the pathological effects. Most of the effects exhibited a nonmonotonic dose response, which might be attributed to the corresponding change in the serum levels of Phe. The results suggest that exposure to low levels of Phe could exert adverse effects on the uterus.

Network medicine-based analysis of the hepatoprotective effects of Amomum villosum Lour. on alcoholic liver disease in rats.

Alcoholic liver disease (ALD) is characterized by high morbidity and mortality, and mainly results from prolonged and excessive alcohol use. Amomum villosum Lour. (A. villosum), a well-known traditional Chinese medicine (TCM), has hepatoprotective properties. However, its ability to combat alcohol-induced liver injury has not been fully explored. The objective of this study was to investigate the hepatoprotective effects of A. villosum in a rat model of alcohol-induced liver disease, thereby establishing a scientific foundation for the potential preventive use of A. villosum in ALD. We established a Chinese liquor (Baijiu)-induced liver injury model in rats. Hematoxylin and eosin (HE) staining, in combination with biochemical tests, was used to evaluate the protective effects of A. villosum on the liver. The integration of network medicine analysis with experimental validation was used to explore the hepatoprotective effects and potential mechanisms of A. villosum in rats. Our findings showed that A. villosum ameliorated alcohol-induced changes in body weight, liver index, hepatic steatosis, inflammation, blood lipid metabolism, and liver function in rats. Network proximity analysis was employed to identify 18 potentially active ingredients of A. villosum for ALD treatment. These potentially active ingredients in the blood were further identified using mass spectrometry (MS). Our results showed that A. villosum plays a hepatoprotective role by modulating the protein levels of estrogen receptor 1 (ESR1), anti-nuclear receptor subfamily 3 group C member 1 (NR3C1), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α). In conclusion, the results of the current study suggested that A. villosum potentially exerts hepatoprotective effects on ALD in rats, possibly through regulating the protein levels of ESR1, NR3C1, IL-6, and TNF-α.