Discovery medicine最新文献

Objective: This study aimed to elucidate the protective effects of quercetin (Que) on the gastric mucosa in a rat model of chronic atrophic gastritis (CAG), with emphasis on the regulation of the transforming growth factor-beta1 (TGF-β1)/Smads signaling pathway.

Methods: Wistar rats were randomly divided into five groups: control, model, low-dose Que (Que-L), and high-dose Que (Que-H). After 30 days of oral gavage, the rats were euthanized for further analysis. Histopathological changes, gastric function (pH, secretion volume, and pepsin activity), and serum levels of gastrin-17 (G-17), interleukin-17 (IL-17), proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), and growth hormone (GH) were evaluated. The expression levels of PCNA, VEGF, TGF-β1, Smad4, and Smad7 were determined by quantitative real-time PCR (qRT-PCR) and Western blot. Gastric epithelial cells-1 (GES-1) cells were infected with Helicobacter pylori (H. pylori) and treated with Que and the TGF-β1/Smad pathway activator SRI-011381. Cell viability, morphological damage, and TGF-β1/Smads pathway expression were subsequently assessed.

Results: Rats in the model group exhibited significantly increased gastric juice pH, decreased total gastric secretion volume and pepsin activity, elevated serum levels of PCNA, VEGF, and EGF, and reduced levels of GH and G-17 (p < 0.05). In gastric tissues, PCNA, VEGF, Smad4, and TGF-β1 were upregulated, while Smad7 was downregulated (p < 0.05). Que treatment improved gastric function, normalized serum biomarkers, and decreased the expression of PCNA, VEGF, Smad4, and TGF-β1, while upregulating Smad7 (p < 0.05). In H. pylori-infected GES-1 cells, Que suppressed PCNA and VEGF expression, enhanced cell viability, and improved nuclear morphology (p < 0.05). It also downregulated TGF-β1 and Smad4 while restoring Smad7 expression. Pretreatment with SRI-011381 attenuated the protective effects of Que (p < 0.05).

Conclusion: Que alleviates gastric inflammation, improves gastric secretory function, and modulates key molecular markers (PCNA, EGF, VEGF, G-17, and GH), thereby protecting against gastric mucosal injury in CAG rats. These effects are likely mediated through inhibition of the TGF-β1/Smads signaling pathway.

Background: Hypertriglyceridemia-induced acute pancreatitis (HTG-AP) is a severe form of pancreatitis, rapidly progressing to multiorgan failure. Growth arrest and DNA damage-inducible beta (GADD45B) play a crucial role in stress responses; however, its precise role in HTG-AP pathogenesis remains unknown. Therefore, this study aimed to elucidate the role of GADD45B in HTG-AP using both in vitro cellular and in vivo animal models.

Methods: AR42J cells were transfected with GADD45B si-RNA or overexpressed plasmids and induced with palmitic acid (PA) and caerulein (Cae) to establish an HTG-AP cellular model. The HTG-AP animal model was successfully developed by treating mice with P-407 and Cae, alongside adeno-associated virus (AAV)-shRNA interference. The transfection efficiency was assessed using quantitative PCR (qPCR) and Western blot analyses. Furthermore, cell viability was evaluated using the Cell Counting Kit-8 (CCK-8) assay, and cell death rate, inflammation levels, and pyroptosis were examined using Hoechst 33342/propidium iodide (PI) staining, enzyme-linked immunosorbent assay (ELISA), and transmission electron microscope (TEM). Moreover, protein expression levels of the pyroptotic pathway, nucleotide-binding and oligomerization domain (NOD)-like receptor family pyrin domain containing 3/Cysteine-dependent aspartate-specific protease 1/Gasdermin D (NLRP3/Caspase-1/GSDMD), were evaluated using Western blot analysis.

Results: The Co-IP assay confirmed the interaction between GADD45B and NLR family pyrin domain containing 3 (NLRP3). In the AR42J cell model of HTG-AP, GADD45B interference promoted cell viability, attenuated cell death, pro-inflammation, pyroptotic cytokines interleukin (IL)-6, tumor necrosis factor-α (TNF-α), IL-1β, IL-18, amylase, and intracellular vesicle counts (p < 0.05). Furthermore, AAV-shGADD45B treatment improved pancreatic injury, cell death, and pyroptosis in HTG-AP model mice (p < 0.05). Moreover, GADD45B knockdown suppressed the pyroptosis-related pathway NLRP3/Caspase-1/GSDMD protein levels (p < 0.05). However, GADD45B overexpression exhibited opposite effects, which was reserved by NLRP3 inhibitor MCC950 (p < 0.05).

Conclusions: This study revealed that GADD45B downregulation reduces pyroptosis by suppressing the NLRP3/Caspase-1/GSDMD axis in HTG-AP, underscoring GADD45B as a promising therapeutic target and enhancing its clinical application.

Background: Cardiovascular diseases, including coronary artery disease (CAD), represent one of the leading causes of death worldwide. Individuals with type 2 diabetes mellitus (T2DM) are susceptible to more severe forms of CAD. Given the strong genetic basis underlying the pathogenesis of T2DM and CAD, this study aimed to investigate the potential significance of the following genetic variants in the pathogenesis of CAD with and without T2DM comorbidity: hepatocyte nuclear factor-1 alpha (HNF1A) [p.I27L] rs1169288, glutathione S-transferase Pi 1 (GSTP1) rs1695 (A>G; Ile→Val), transcription factor 7-like 2 (TCF7L2) rs7903146 (C>T), and long non-coding RNA H19 (LncRNA H19) rs217727 (C>T).

Methods: Three hundred subjects were enrolled in this study, containing 200 cases of CAD (100 non-diabetic and 100 diabetic) and 100 healthy individuals as controls. The genotyping studies were conducted using amplification-refractory mutation system polymerase chain reaction (ARMS-PCR).

Results: Demographic and clinical characteristics associated with the two CAD groups demonstrated significant differences. Additionally, a significant difference in genotype frequencies of the GSTP1 (rs1695 A>G) gene polymorphism was detected between CAD patients and healthy controls, with the GG genotype being more common in CAD patients (18% in non-diabetic and 20% in diabetic) than in the healthy controls (3%) (p < 0.0001 and p = 0.00003). Those with the GG genotype had a notably higher risk of developing CAD, regardless of T2DM comorbidity. The LncRNA H19 (rs217727 C>T) gene polymorphism displayed significant differences in genotype frequencies between healthy controls and non-diabetic CAD patients, but not in diabetic CAD patients. The TT genotype was much more common in non-diabetic CAD patients (20%) compared to healthy controls (6%, p = 0.0006), with nondiabetic patients also having a higher frequency of the T allele (0.42 vs. 0.23 in controls). Similarly, the TCF7L2 (rs7903146 C>T) gene polymorphism displayed significant differences in genotype frequencies between healthy controls and non-diabetic CAD patients, instead of diabetic CAD patients. The CT heterozygous genotype was more common in non-diabetic CAD patients (63%) than in healthy controls (35%, p = 0.0001). The HNF1A (rs1169288 G>T) gene polymorphism showed significant differences in genotype frequencies between healthy controls and diabetic CAD patients, but not between non-diabetic CAD patients. The TT genotype was notably overrepresented in diabetic CAD patients (8%) than in healthy controls (1%, p = 0.04), and diabetic patients also had a higher frequency of the T allele (0.38 vs. 0.33 in controls).

Conclusion: The data from the current study have identified certain genetic variants of interest in the given population as risk marker

Background: Ageing is associated with a significant decline in olfactory function, though the underlying mechanisms remain unclear. Angiotensinogen (AGT) participates in multiple cellular processes, including inflammation, oxidative stress (OS), and magnesium (Mg²⁺) homeostasis. In this study, we investigated how decreased AGT expression in olfactory epithelial cells affects Mg²⁺ uptake, inflammation, oxidative stress, and mitochondrial apoptosis, ultimately contributing to olfactory dysfunction.

Methods: Rapidly ageing male senescence-accelerated mouse prone 6 (SAMP6) mice and age-matched normal senescence accelerated mouse resistant 1 (SAMR1) control mice were used to evaluate olfactory function via the buried food test. Blood and olfactory epithelium tissues were collected for biochemical analyses. Mouse olfactory epithelial (MOE) cells were cultured, and AGT expression was knocked down, with or without MgSO₄ supplementation. Mitochondrial membrane potential (Δψm) was assessed using JC-1 staining, and cell viability was measured via Cell Counting Kit-8 (CCK-8) assay.

Results: SAMP6 mice exhibited impaired olfactory function, with significant structural damage to the olfactory epithelium and reduced expression of olfactory marker protein (OMP, p < 0.05). Elevated expression of interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), reactive oxygen species (ROS), Bcl-2-associated X protein (Bax), caspase-3, and caspase-9 was observed in blood and olfactory epithelium tissues, while levels of AGT, Angiotensin II (Ang II), Mg²⁺, and the Mg²⁺ transporter mitochondrial RNA splicing 2 protein (MRS2) and transient receptor potential cation channel subfamily M member 6 (TRPM6) were significantly decreased (p < 0.05). In vitro, AGT knockdown reduced viability and Δψm in MOE cells (p < 0.05), elevated IL-1β, TNF-α and ROS (p < 0.05), and suppressed the expression of AGT, Ang II, MRS2, and TRPM6 (p < 0.05). Notably, MgSO₄ administration partially reversed the effects of AGT knockdown on MOE cells (p < 0.05).

Conclusion: Reduced AGT expression in olfactory epithelial cells impairs Mg²⁺ uptake, leading to inflammation, oxidative stress, and mitochondrial apoptosis, ultimately contributing to age-related olfactory dysfunction. Our findings suggest that targeting AGT or Mg²⁺ homeostasis may offer promising therapeutic strategies for age-related olfactory disorders.

Aim: Primary sarcomatoid carcinoma (PSC) of the lung is a rare malignant neoplasm characterized by the presence of both carcinomatous and sarcomatoid components, typically presenting as a solitary pulmonary mass. Imaging examination serves as a critical tool for the detection and evaluation of pulmonary lesions, the definitive diagnosis of PSC still relies on histopathological examination and immunohistochemical staining results. This study presents a pathologically confirmed case of PSC of the lung with a retrospective analysis of the clinical features and chest computed tomography (CT) imaging findings. The purpose is to improve the diagnostic accuracy of this disease.

Case presentation: A 67-year-old Chinese male was admitted to the First People's Hospital of Tong Xiang City with a one-week history of cough and expectoration. A plain and contrast-enhanced chest CT scan revealed a large mass in the upper lobe of the right lung, adjacent to the interlobar fissure and parietal pleura. Upon enhancement, the mass demonstrated irregular mild-to-moderate enhancement on the side near the pleura, with no significant enhancement in the central region or near the hilum. A pseudocapsule was observed surrounding the lesion. The patient subsequently underwent resection of the right upper lobe mass. Hematoxylin-eosin staining of the pathological specimen revealed spindle-shaped tumor cells that had invaded the parietal pleura. Immunohistochemical analysis showed positivity for vimentin and cytokeratin, as well as partial positivity for epithelial membrane antigen. Based on these immunohistochemical findings, the tumor was diagnosed as pulmonary sarcomatoid carcinoma (spindle cell type). Approximately 10 months postoperatively, the patient was readmitted due to chest pain and dyspnea lasting four days. The chest CT scan indicated tumor recurrence. The patient was managed conservatively for two months, achieving stable condition before discharge. Two months after discharge, the patient succumbed to complications of concurrent pulmonary infection and cardiopulmonary failure.

Results: Analyzing the pathological findings and CT manifestations in a patient with pulmonary PSC; immunohistochemical staining results can to some extent provide insights into the patient's prognosis.

Conclusions: Owing to the rarity, high-degree malignancy and poor prognosis of PSC, potential cases should be comprehensively evaluated based on imaging, laboratory and pathological results. Long-term regular follow-up is required to rule out the metastasis or recurrence of postoperative pleural metastasis.

Background: To analyze the efficacy of the improved sampling method in enhancing the accuracy of Human Epidermal Growth Factor Receptor 2 (HER2) detection within gastric cancer surgical specimens, in order to decrease the false negative rate of HER2 detection results.

Methods: In this study, the participants were gastric cancer patients recruited from the Shandong Cancer Hospital Affiliated with Shandong First Medical University. Between December 2018 to August 2020, 310 surgical specimens of gastric cancer were procured and processed using traditional sampling methods. Biopsy specimens (n = 235), and surgical specimens (n = 400) indicated for processing by improved sampling methods, were obtained during the period from September 2020 to July 2021. Clinical data including sex, age, stage, degree of differentiation, tumor site, operation duration and blood loss was collected. Sex, operation duration and blood loss among three groups were compared by One-Way analysis of variance (ANOVA), and sex, stage, degree of differentiation and tumor site comparisons were performed by Chi-squared test (χ²). HER2 detection was carried out for all specimens by means of immunohistochemical (IHC) assay. The results of HER2 detection among three groups were compared by Chi-squared test (χ²) using SPSS software.

Results: There was no significant correlation between HER2 expression and pathological stage (p = 0.468). HER2 expression was related to tumor differentiation and tumor site: the HER2 expression in moderately differentiated tumors was higher than that in poorly differentiated tumors (p < 0.001); and it was significantly higher in gastric fundus than that in the gastric body and antrum (p = 0.031). The positive expression of HER2 in gastric cancer was 59.3% (0), 20.0% (1+), 13.4% (2+) and 7.3% (3+). Among them, a 2+ HER2 expression rate of 11.3%, 11.1%, and 16.5% were detected in specimens processed by the traditional sampling method, biopsy method, and tissues processed by improved sampling method, respectively. Meanwhile, a 3+ HER2 expression rate was found to be 4.8%, 8.1%, and 8.8%, respectively, for the specimens in the same order. Evidently, 1+ HER2 expression rate in specimens obtained by the improved sampling method and biopsy method was higher than in those by traditional sampling method (p < 0.001 and p = 0.007, respectively).

Conclusions: The improved sampling method significantly improves the positive HER2 expression rate (1+) in gastric cancer specimens, thereby reducing false-negative HER2 detection rates by immunohistochemistry. This method warrants further clinical implementation, particularly in resource-limited settings.

Background: Implants are commonly used to repair teeth. However, with their widespread use, the incidence of peri-implantitis has also increased. The Mitogen activated protein kinase/Protein kinase B/Nuclear factor kappa-B (MAPK/AKT/NF-κB) signaling pathway is associated with various inflammatory responses. This study aims to evaluate the role of resveratrol in managing peri-implant inflammation and its regulatory effect on the MAPK/AKT/NF-κB signaling pathway.

Methods: Peri-implant bone loss was measured by micro-computed tomography, and gingival cell apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. The levels of apoptosis-related proteins (caspase-3, B-cell lymphoma-2 (Bcl-2)), inflammation-related proteins (caspase-1, phospho-p65 (p-p65)/p65), and MAPK/AKT/NF-κB signaling pathway-related proteins (p38 MAPK, AKT, and NF-κB) in inflammatory tissue were determined by western blotting. Enzyme-linked immunosorbent assay was used to measure the levels of tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), IL-1β, IL-4, and IL-10 in the serum of mice. Biochemical kits were used to measure the levels of malondialdehyde (MDA), nitric oxide (NO), and superoxide dismutase (SOD) in inflammatory tissue. The intercellular reactive oxygen species (ROS) content was detected by ROS staining, and the morphology of inflammatory tissue was observed by hematoxylin-eosin (HE) and tartrate-resistant acid phosphatase (TRAP) staining.

Results: The administration of resveratrol significantly reduced bone loss around the implant and prevented the apoptosis of gingival cells (p < 0.001). Additionally, resveratrol effectively reduced the concentration of serum inflammatory factors and inflammation-related proteins, namely caspase-1 and p-p65/p65 (p < 0.001). Additionally, in the resveratrol intervention group, the contents of MDA and NO, and the level of ROS decreased, while the content of SOD increased (p < 0.05). The HE, immunofluorescence, and TRAP staining results confirmed that resveratrol effectively reduced the number of total inflammatory cells in gingival tissue (p < 0.05).

Conclusion: Resveratrol has the potential to alleviate peri-implant inflammation and regulate the MAPK/AKT/NF-κB signaling pathway. This offers a novel approach for drug-based clinical interventions in peri-implant inflammation.

Background: Traumatic neuronal injury (TNI), a type of traumatic brain injury (TBI), features apoptosis of cortical neurons. Knowing that docosahexaenoic acid (DHA) is enriched in the neuronal cell membranes and related to brain function, we aimed to study the mechanism behind the effect of DHA on TNI model neurons.

Methods: Neurons were derived from Sprague-Dawley rats and a TNI model was established by using a rotating scribe injury device. Four experimental groups were set up based on neuronal injury and DHA concentration, namely the Control, TNI, TNI + DHA-25, and TNI + DHA-50 groups. The cell morphology, toxicity and neuron apoptosis were assessed by means of light microscopy, lactate dehydrogenase (LDH) release assessment, and terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, respectively. Protein levels of sorcin (SRI), activating transcription factor 6 (ATF6), glucose-regulated protein 78 (GRP78), C/Ebp-homologous protein (CHOP), cleaved-caspase-12 (C-Cas-12) and presenilin 2 (PSEN2) were determined by western blotting. PSEN2 overexpression plasmid and short hairpin RNA against SRI (shSRI) were used for transfection. In the transfection experiment, neurons were assigned into six groups, namely TNI, TNI + DHA-50, short hairpin RNA for negative control (shNC) + Vector, PSEN2, shSRI, and PSEN2 + shSRI groups, and the latter four groups were treated with TNI + DHA. PSEN2 and SRI mRNA levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cytotoxicity-, apoptosis- and endoplasmic reticulum stress (ERS)-related proteins were examined in the neurons.

Results: DHA at a dose of 50 μM attenuated TNI-induced neuronal injury, cell toxicity (p < 0.001), cell apoptosis (p < 0.001), and levels of ERS-related proteins (ATF6, GRP78, CHOP and C-Cas-12) (p < 0.001), PSEN2 and SRI in neurons (p < 0.001). Besides, 50 μM of DHA regulated cell toxicity, cell apoptosis and ERS-related proteins by modulating the interaction between PSEN2 and SRI in neurons (p < 0.05).

Conclusions: DHA mitigates neuron apoptosis induced by SRI-activated ERS via targeting PSEN2.