Alzheimer's Disease and Aging Association: Identification and Validation of Related Genes

BACKGROUND

Aging is considered a key risk factor for Alzheimer's disease (AD). This study aimed to identify and validate potential aging-related genes associated with AD using bioinformatics analysis.

METHODS

Datasets GSE36980 and GSE5281 were selected to screen differentially expressed genes (DEGs), and the immune cell correlation analysis and GSEA analysis of DEGs were performed. The intersection with senescence genes was taken as differentially expressed senescence-related genes (DESRGs), and the GSE44770 dataset was used for further validation. The potential biological functions and signaling pathways were determined by GO and KEGG, and the hub genes were identified by 12 algorithms in Cytohubba. The expression of 10 hub genes in different brain regions was determined and single-cell sequencing analysis was performed, and diagnostic genes were further screened by gene expression and receiver operating characteristic (ROC) curve. Finally, a miRNA-gene network of diagnostic genes was constructed and targeted drug prediction was performed.

RESULTS

A total of 2137 DEGs were screened from the GSE36980 and GSE5281 datasets, and 278 SRGs were identified from the CellAge database. The overlapping DEGs and SRGs constituted 29 DESRGs, including 14 senescence suppressor genes and 15 senescence inducible genes. The top 10 hub genes, including MDH1, CKB, PSMD14, SMARCA4, PEBP1, DDB2, ITPKB, ATF7IP, YAP1, and EWSR1 were screened. Furthermore, four diagnostic genes were identified: PMSD14, PEBP1, ITPKB, and ATF7IP. The ROC analysis showed that the respective area under the curves (AUCs) of PMSD14, PEBP1, ITPKB, and ATF7IP were 0.732, 0.701, 0.747, and 0.703 in the GSE36980 dataset and 0.870, 0.817, 0.902, and 0.834 in the GSE5281 dataset. In the GSE44770 dataset, PMSD14 (AUC, 0.838) and ITPKB (AUC, 0.952) had very high diagnostic values in the early stage of AD. Finally, based on these diagnostic genes, we found that the drug Abemaciclib is a targeted drug for the treatment of age-related AD. Flutamide can aggravate aging-related AD.

CONCLUSION

The results of this study suggest that cellular SRGs might play an important role in AD. PMSD14, PEBP1, ITPKB, and ATF7IP have the potential as specific biomarkers for the early diagnosis of AD.

Protective Effects of Relaxin 2 (RLXH2) against Hypoxia-Induced Oxidative Damage and Cell Death via Activation of The Nrf2/HO-1 Signalling Pathway in Gastric Cancer Cells

OBJECTIVE

This study aims to investigate the potential role of relaxin, a peptide hormone, in preventing cellular deterioration and death in gastric carcinoma cells under hypoxic conditions. It explores the effects of recombinant relaxin 2 (RLXH2) on growth, cell differentiation, invasive potential, and oxidative damage in these cells.

MATERIALS AND METHODS

In this experimental study, the NCI-N87 cell line was cultured under normal conditions and then subjected to hypoxia using cobalt chloride (CoCl2). The cells were treated with RLXH2, and various assays were performed to assess cellular deterioration, death, and oxidative stress. Western blot and quantitative real time polymerase chain reaction (qRT-PCR) were used to measure the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1, and the translocation of Nrf2 to the nucleus was confirmed through Western blot analysis.

RESULTS

This study demonstrates, for the first time, that RLXH2 significantly reduces the formation of reactive oxygen species (ROS) and the release of lactate dehydrogenase (LDH) in gastric cancer cells under hypoxic conditions. RLXH2 also enhances the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), leading to a decrease in hypoxia-induced oxidative damage. RLXH2 promotes the translocation of Nrf2 to the nucleus, resulting in HO-1 expression.

CONCLUSION

Our findings suggest that RLXH2 plays a significant protective role against hypoxia-induced oxidative damage in gastric carcinoma cells through the Nrf2/HO-1 signalling pathway. This research contributes to a better understanding of the potential therapeutic applications of RLXH2 in gastric cancer treatment.

Mesenteric ischaemia in a case of acute anterior myocardial infarction: overlap of ischaemic types

Acute mesenteric ischaemia is divided into different clinical entities which are usually considered separately. Here we report a case of acute mesenteric ischaemia complicated with acute anterior myocardial infarction. The clinical picture suggested that non-occlusive mesenteric ischaemia and acute mesenteric arterial thrombosis were both present in this case. Thus, non-occlusive and occlusive ischaemia may coexist in a coordinated and perceptible pattern.

Transferrin-Modified Mangiferin-Loaded SLNs: Preparation, Characterization, and Application in A549 Lung Cancer Cell

Introduction

Mangiferin is a plant antitumor compound with poor water solubility and low bioavailability. In this study, transferrin-modified mangiferin-loaded solid lipid nanoparticles (Tf-modified MGF-SLNs) were prepared to overcome the above defects.

Methods

Tf-modified MGF-SLNs were prepared by the emulsification-solvent evaporation method. The physicochemical properties of Tf-MGF-SLNs such as particle size, zeta potential and in vitro drug release were investigated. We also demonstrated the effect of Tf-MGF-SLNs in lung cancer.

Results

The mean hydrodynamic diameter of the Tf-MGF-SLNs was 121.8±2.9 nm with a polydispersity index of 0.134±0.03. According to TEM micrographs, Tf-MGF-SLNs are spherical and uniform, and the EE% was found to be 72.5±2.4%. In vitro release, we identified an initial burst effect release, followed by controlled release, in SLNs at both pHs and the Tf-MGF-SLNs drug accumulation release percentages reached over 68% at pH 4.0 and 72% at pH 7.4 in 6 hours, respectively. In vivo studies showed that depending on surface modification, Tf-MGF-SLNs, which suggested that cell internalization was changed and more drugs entered the cells successfully.

Discussion

Tf-MGF-SLNs were highly efficient in suppressing the tumor growth in xenograft tumor model. Sustained release of the drug delivery system and Tf-modified MGF-SLNs played a major role. Tf-MGF-SLNs would be a promising formulation for the treatment of lung cancer.

Circular RNA Paired-Related Homeobox 1 Promotes Gastric Carcinoma Cell Progression via Regulating MicroRNA-665/YWHAZ Axis

BACKGROUND

Gastric carcinoma (GC) is a ubiquitous malignant tumor worldwide. Circular RNA paired-related homeobox 1 (circ-PRRX1), one kind of non-coding RNAs, has been reported to act as a promoter in tumor growth. This study aims to explore the effects of circ-PRRX1 on proliferation, apoptosis, and metastasis in GC and the underlying regulatory mechanisms.

METHODS

The expression of circ-PRRX1, miR-665, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ) mRNA was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used to analyze YWHAZ protein expression. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-Htetrazolium bromide (MTT), flow cytometry, and transwell assay were carried out to assess the viability, apoptosis, migration, and invasion in GC cells. The interaction between miR-665 and circ-PRRX1 or YWHAZ was predicted by StarBase v2.0 and identified by dual-luciferase reporter system. Xenograft mouse model was employed to determine the effects of circ-PRRX1 knockdown on GC growth in vivo.

RESULTS

Compared with normal tissues and cells, circ-PRRX1 and YWHAZ levels were upregulated, and miR-665 was downregulated in GC tissues and cells. Functionally, circ-PRRX1 knockdown inhibited the viability, migration, and invasion and promoted apoptosis in GC cells, whereas anti-miR-665 abolished these effects. Mechanistically, circ-PRRX1 was confirmed as a sponge of miR-665 to regulate YWHAZ expression. Xenograft mouse model suggested that circ-PRRX1 knockdown reduced GC cells growth in vivo.

CONCLUSION

Circ-PRRX1 knockdown suppressed GC development by targeting miR-665 to inhibit YWHAZ expression, and the potential molecular mechanism may provide a theoretical basis for GC therapy.

Bufalin inhibits the growth and epithelial to mesenchymal transition of human gastric cancer cells via modulation of MEK/ERK pathway

This study was designed to evaluate the anti-cancer effects of bufalin against the human gastric cancer cells and unveil the underlying mechanism. The results showed that bufalin inhibited the proliferation and colony formation of the MGC-803 gastric cancer cells and exhibited an IC50 of 10 μM. These antiproliferative effects were found to be due to the induction of G2/M cell cycle arrest. The G2/M cell cycle arrest was also concomitant with inhibition of cdc2, cdc25 and cyclin B1. Furthermore, bufalin suppressed the epithelial-to-mesenchymal transition, migration, and invasion of the MGC-803 gastric cancer cells. The Western blot analysis revealed that bufalin exerted its effects via deactivation of EK/ERK signaling pathway. Taken together, these results suggest the potential of bufalin as the lead molecule for the development of chemotherapy for gastric cancer.  

The E3 ubiquitin ligase Cbl-b inhibits tumor growth in multidrug-resistant gastric and breast cancer cells

Most receptor tyrosine kinases (RTKs) contribute to tumor growth, and their ubiquitination and degradation is related to the inhibition of tumor growth. Our previous study showed that the ubiquitin ligase Cbl-b was expressed at low levels in multidrug-resistant (MDR) gastric cancer cells compared with their parental cells. However, whether enhancement of Cbl-b expression in MDR cancer cells could prevent tumor proliferation via ubiquitination and degradation of RTK remains unclear. In the present study, Cbl-b overexpression reduced cell proliferation in MDR gastric and breast cancer cells, and effectively inhibited tumor growth in vivo. Additionally, Cbl-b overexpression reduced the total protein level of insulin-like growth factor 1 (IGF-1R), an important member of the RTK family. Moreover, Cbl-b overexpression promoted interaction of Cbl-b with IGF-1R, and induced ubiquitination and degradation of IGF-1R and inactivation of the IGF-1R pathway. These results suggest that the ubiquitin ligase Cbl-b inhibited tumor growth via ubiquitination and degradation of IGF-1R in MDR gastric and breast cancer cells.

Exosomes promote cetuximab resistance via the PTEN/Akt pathway in colon cancer cells

Cetuximab is widely used in patients with metastatic colon cancer expressing wildtype KRAS. However, acquired drug resistance limits its clinical efficacy. Exosomes are nanosized vesicles secreted by various cell types. Tumor cell-derived exosomes participate in many biological processes, including tumor invasion, metastasis, and drug resistance. In this study, exosomes derived from cetuximab-resistant RKO colon cancer cells induced cetuximab resistance in cetuximab-sensitive Caco-2 cells. Meanwhile, exosomes from RKO and Caco-2 cells showed different levels of phosphatase and tensin homolog (PTEN) and phosphor-Akt. Furthermore, reduced PTEN and increased phosphorylated Akt levels were found in Caco-2 cells after exposure to RKO cell-derived exosomes. Moreover, an Akt inhibitor prevented RKO cell-derived exosome-induced drug resistance in Caco-2 cells. These findings provide novel evidence that exosomes derived from cetuximab-resistant cells could induce cetuximab resistance in cetuximab-sensitive cells, by downregulating PTEN and increasing phosphorylated Akt levels.

Low-level miR-646 in colorectal cancer inhibits cell proliferation and migration by targeting NOB1 expression

Aberrant expression of microRNA (miRNA) is important in the progression of various human cancers, however further investigation is required in order to fully elucidate mechanisms of and validate actions of endogenous non-coding RNAs. The present study demonstrated that the expression of miR-646 was downregulated in colorectal cancer tissues and cell lines. Notably, it was observed that miR-646, a tumor suppressor, inhibited colorectal cancer cell progression through directly targeting Nin one binding protein (NOB1) expression, which possesses anti-tumor properties in colorectal cancer. Furthermore, knockdown of NOB1 expression was responsible for the tumor-suppressive effect of miR-646. The findings suggest that miR-646 may act as a therapeutic target for the treatment of colorectal cancer.

[Analysis of the diagnosis and treatment of cerebrospinal fluid otorrhea]

Objective:To analyze the etiology and clinical symptoms and to investigate the therapeutic strategies of cerebrospinal fluid otorrhea. Method:A retrospective analysis of 37 cases of patients with cerebrospinal fluid otorrhea.The clinical symptoms, auxiliary examination, intraoperative findings, surgical methods and postoperative follow-up were analyzed. Result:In 37 cases, 35 patients underwent the plugging surgery once and cured, 1 patient with inner ear malformation underwent another operation and cured, 1 patient didn't have the operation. No cerebrospinal fluid leakage or meningitis recurrence was reported by the followed up from 1 months to 7 years after operation. Conclusion:Surgical repair is an effective method to treat the cerebrospinal fluid otorrhea. It is significant to take appropriate surgical approach to expose and to find the leak, according to the etiological factor and imaging examination.

Devolopmental and growth temperature regulation of omega-3 fatty acid desaturase genes in safflower (Carthamus tinctorius L.)

Three ω-3 fatty acid desaturase genes (CtFAD3, CtFAD7, and CtFAD8) were isolated from safflower (Carthamus tinctorius L.). Transcript analysis showed that the highest transcript levels were detected for CtFAD3 and the low transcript levels were detected for CtFAD7 and CtFAD8 in flowers. This result indicates that CtFAD3 enzyme activity is important for fatty acid desaturation in flowers. The low transcript level of CtFAD3 in developing seeds was consistent with the recorded high level of linoleic acid (18:2) and lack of linolenic acid (18:3) in safflower seed oil. At low temperatures, the induced transcription levels of ω-3 fatty acid desaturase genes in the stems and petioles were consistent with increased polyunsaturated fatty acids (PUFAs). In the roots, ω-3 fatty acid desaturase noticeably increased at low temperatures, whereas PUFA levels decreased. Interestingly, C18:3(Δ9,12,15) alcohol was specifically found in safflower roots, and showed a significant increase, indicating a flux in the acid to alcohol ratio of this compound in safflower roots.

Endotoxin removal by charge-modified filters

The effects of positively charged nylon and depth (cellulose-diatomaceous earth) filters on endotoxin removal from various solutions were evaluated. The charged filter media removed significant amounts of Escherichia coli and natural endotoxin from tap water, distilled water, sugars, and NaCl solutions; no significant removal of endotoxin was observed with negatively charged filter media. The extent of removal was influenced by pH, the presence of salts, and organic matter. Such media may be useful for the control of endotoxins in raw-product water or solutions used to prepare parenteral drug products or in other fluids where endotoxin control is desired.

Capture of latex beads, bacteria, endotoxin, and viruses by charge-modified filters

This report demonstrates how electropositive filters can be used to enhance the removal of microorganisms and other negatively charged particles from water. It was shown that electropositive depth filters were capable of adsorbing viruses and endotoxins many times smaller than the average pore size of the filter. Electronegative filters of similar porosity or electropositive filters that had been treated to destroy the positive charge were almost ineffective under similar conditions for the removal of viruses and small latex spheres. The results of this study indicate that electropositive filters are highly effective in the removal of a wide range of contaminants over a wide range of pH values and ionic conditions.