Cell Biology International最新文献

Oxidative stress plays a pivotal role in the development of diabetic cardiomyopathy (DCM). Previous studies have revealed that inhibition of mitochondrial fission suppressed oxidative stress and alleviated mitochondrial dysfunction and cardiac dysfunction in diabetic mice. However, no research has confirmed whether mitochondria fission accentuates hyperglycemia-induced cardiomyoblast oxidative stress through regulating fatty acid oxidation (FAO). We used H9c2 cardiomyoblasts exposed to high glucose (HG) 33 mM to simulate DCM in vitro. Excessive mitochondrial fission, poor cell viability, and lipid accumulation were observed in hyperglycemia-induced H9c2 cardiomyoblasts. Also, the cells were led to oxidative stress injury, lower adenosine triphosphate (ATP) levels, and apoptosis. Dynamin-related protein 1 (Drp1) short interfering RNA (siRNA) decreased targeted marker expression, inhibited mitochondrial fragmentation and lipid accumulation, suppressed oxidative stress, reduced cardiomyoblast apoptosis, and improved cell viability and ATP levels in HG-exposed H9c2 cardiomyoblasts, but not in carnitine palmitoyltransferase 1 (CPT1) inhibitor etomoxir treatment cells. We also found subcellular localization of CPT1 on the mitochondrial membrane, FAO, and levels of nicotinamide adenine dinucleotide phosphate (NADPH) were suppressed after exposure to HG treatment, whereas Drp1 siRNA normalized mitochondrial CPT1, FAO, and NADPH. However, the blockade of FAO with etomoxir abolished the above effects of Drp1 siRNA in hyperglycemia-induced H9c2 cardiomyoblasts. The preservation of mitochondrial function through the Drp1/CPT1/FAO pathway is the potential mechanism of inhibited mitochondria fission in attenuating oxidative stress injury of hyperglycemia-induced H9c2 cardiomyoblasts.

ATAD3 is a vital ATPase of the inner mitochondrial membrane of pluri-cellular eukaryotes, with largely unknown functions but early required for organism development as necessary for mitochondrial biogenesis. ATAD3 knock-down in C. elegans inhibits at first the development of adipocyte-like intestinal tissue so we used mouse adipocyte model 3T3-L1 cells to analyze ATAD3 functions during adipogenesis and lipogenesis in a mammalian model. ATAD3 function was studied by stable and transient modulation of ATAD3 expression in adipogenesis- induced 3T3-L1 cells using Knock-Down and overexpression strategies, exploring different steps of adipocyte differentiation and lipogenesis. We show that (i) an increase in ATAD3 is preceding differentiation-induced mitochondrial biogenesis; (ii) downregulation of ATAD3 inhibits adipogenesis, lipogenesis, and impedes overexpression of many mitochondrial proteins; (iii) ATAD3 re-expression rescues the phenotype of ATAD3 KD, and (iv) differentiation and lipogenesis are accelerated by ATAD3 overexpression, but inhibited by expression of a dominant-negative mutant. We further show that the ATAD3 KD phenotype is not due to altered insulin signal but involves a limitation of mitochondrial biogenesis linked to Drp1. These results demonstrate that ATAD3 is limiting for in vitro mitochondrial biogenesis and adipogenesis/lipogenesis and therefore that ATAD3 mutation/over- or under-expression could be involved in adipogenic and lipogenic pathologies.

Mansonone G (MG), a 1,2-naphthoquinones with antiestrogenic, antimicrobial, and anti-adipogenic activities, is derived from the heartwood of Mansonia gagei Drumm. Ethoxy mansonone G (EMG), an essential derivative of MG, has anticancer and antioxidant agent. EMG also has antiestrogen activity and is demonstrated to lower estrogen receptor expression in endocrine-resistant cells. EMG significantly inhibits cell division, invasion, and anchorage-dependent growth in all cancer types. Through the stimulation of the tumor protein (p53) and extracellular signal-regulated kinase (ERK) signaling cascades, it also causes apoptosis. Moreover, it manifests its anti-cancerous effects in toll-like receptor pathways, c-Jun N-terminal kinase (c-JNK), and nuclear factor kappa B (NF-κB). EMG inhibits the phosphorylation of glycogen synthase kinase (GSK3), Erk, protein kinase B (Akt), and mammalian target of rapamycin (mTOR). By interfering with molecular cascades, EMG significantly reduces the metabolism of cancer cells. This paper focuses on the potential use of EMG in cancer treatment. Moreover, it states the methodology by which specific assays establish the anti-cancerous role of EMG. Breast cancer, non-small cell lung cancer, and colorectal cancer are only a few of the cancers for which EMG was shown to be effective. Through further research, EMG may be developed as a therapeutic solution to complications caused by cancer. This study presents EMG as a novel candidate for cancer therapy, offering a unique combination of pharmacological advantages and mechanistic insights that warrant further exploration and development toward addressing the complexities of cancer treatment.

We evaluated the influence of different media plus various concentrations of Glial cell line-derived neurotrophic factor (GDNF) during the in vitro culture (IVC) of testicular tissues from prepubertal collared peccary. Testes from 5 individuals were collected, fragmented and cultured for 28 days (34°C and 5% CO₂). Culture media were Dulbecco's modified essential medium (DMEM) or stem cell serum free media (StemPro-34™ SFM), both supplemented with various concentrations of GDNF (0, 10, or 20 ng/mL). Fragments were cultured on the flat surface of 0.75% agarose gel and were evaluated every 7 days for fragment area, histomorphology, cellular viability, and proliferative activity. Data were expressed as mean ± standard error and analyzed by Kruskal–Wallis's and Tukey test. Fragments area decreased over the 28 days-culture, regardless of the treatment. For morphology, the StemPro-37 SFM medium plus 10 ng/mL GDNF provided higher scores at all time points in comparison to DMEM using any GDNF concentration (p < .05). After 28 days, similar cellular viability (~70%) was observed in all treatments (p > .05). For proliferating cell nuclear antigen assay, only DMEM plus 10 ng/mL GDNF improved (p < .05) cellular proliferation on Days 14 and 28. Looking at argyrophilic nucleolar organizing regions, after 28 days, there were no differences among treatments regarding cell proliferative capacity for both spermatogonia and Sertoli cells (p > .05). In summary, the DMEM and StemPro-34 SFM are adequate medium for IVC of prepubertal peccary testicular tissue. Supplementation with GDNF, especially at a 10 ng/mL concentration, appears to be essential for the maintenance of cell survival and proliferation.

Cationic liposomes composed of cholesteryl-3β-carboxyamidoethylene-N-hydroxyethylamine (OH-chol) and 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) inhibit mast cell degranulation mediated via crosslinking of high-affinity IgE receptors (FcεRI). Although the inhibitory efficiency of mast cell degranulation is altered by modifying the ratio of OH-chol and DOPE in cationic liposomes, the manner in which physicochemical properties, such as surface charge and size, influence suppression is not clear. We observed that positive surface charge, but not the size, of liposomes plays a role in suppressing rat basophilic leukemia (RBL-2H3) cell activation. Pretreatment with middle-ratio OH-chol liposomes (zeta potential, 62.2 ± 0.5 mV; diameter, 325.4 ± 7.3 nm) exhibited a larger suppression of RBL-2H3 cell degranulation evoked by FcεRI crosslinking compared with that by low-ratio OH-chol liposomes (zeta potential, 48.6 ± 1.9 mV; diameter, 344.4 ± 25.0 nm), although both liposomes were similarly attached to RBL-2H3 cells. Preparation of middle-ratio OH-chol liposomes, classified roughly by size using an extrusion method, revealed that the liposomal size did not affect the inhibitory efficiency of RBL-2H3 cell activation. Mechanistically, we found that middle-ratio OH-chol liposomes increased the inhibition of antigen-induced Akt phosphorylation compared to low-ratio OH-chol liposomes. We measured the phosphorylation of linker for activation of T cells (LAT) and paxillin, which are important proteins in FcεRI- and focal adhesions (FAs)-mediated signaling, respectively. Middle ratio OH-chol liposomes significantly suppressed antigen-induced paxillin phosphorylation, but did not affect LAT phosphorylation, suggesting that middle-ratio OH-chol liposomes attached to RBL-2H3 cells suppress the degranulation by impairing FA-mediated Akt phosphorylation evoked by FcεRI crosslinking.

Lung adenocarcinoma (LUAD) is the most common subtype of NSCLC, characterized by poor prognosis and frequently diagnosed at advanced. While previous studies have demonstrated pleckstrin-2 (PLEK2) as aberrantly expressed and implicated in tumorigenesis across various tumor types, including LUAD, the molecular mechanisms underlying PLEK2-mediated LUAD progression remain incompletely understood. In this study, we obtained data from The Cancer Genome Atlas (TCGA) database to assess PLEK2 expression in LUAD, a finding further confirmed through analysis of human tissue specimens. PLEK2-silenced LUAD cellular models were subsequently constructed to examine the functional role of PLEK2 both in vitro and in vivo. Our results showed elevated PLEK2 expression in LUAD, correlating with poor patients' prognosis. PLEK2 knockdown led to a significant suppression of LUAD cell proliferation and migration, accompanied by enhanced apoptosis. Moreover, tumor growth in mice injected with PLEK2-silencing LUAD cells was impaired. Gene expression profiling and Co-IP assays suggested direct interaction between PLEK2 and SPC25, with downregulation of SPC25 similarly impairing cell proliferation and migration. Additionally, we revealed phosphoinositide 3-kinase (PI3K)/AKT signaling activation as requisite for PLEK2-induced malignant phenotypes in LUAD. Collectively, our findings underscore PLEK2's oncogenic potential in LUAD, suggesting its utility as a prognostic indicator and therapeutic target for LUAD management.

Ecto-5′-nucleotidase (CD73) hydrolyses 5′AMP to adenosine and inorganic phosphate. Breast cancer cells (MDA-MB-231) express high CD73 levels, and this enzyme has been found to play a tumour-promoting role in breast cancer. However, no studies have sought to investigate whether CD73 has differential affinity or substrate preferences between noncancerous and cancerous breast cells. In the present study, we aimed to biochemically characterise ecto-5′-nucleotidase in breast cancer cell lines and assess whether its catalytic function and tumour progression are correlated in breast cancer cells. The results showed that compared to nontumoral breast MCF-10A cells, triple-negative breast cancer MDA-MB-231 cells had a higher ecto-5′-nucleotidase expression level and enzymatic activity. Although ecto-5′-nucleotidase activity in the MDA-MB-231 cell line showed no selectivity among monophosphorylated substrates, 5′AMP was preferred by the MCF-10A cell line. Compared to the MCF-10A cell line, the MDA-MB-231 cell line has better hydrolytic ability, lower substrate affinity, and high inhibitory potential after treatment with a specific CD73 inhibitor α,β‑methylene ADP (APCP). Therefore, we demonstrated that a specific inhibitor of the ecto-5-nucleotidase significantly reduced the migratory and invasive capacity of MDA-MB-231 cells, suggesting that ecto-5-nucleotidase activity might play an important role in metastatic progression.

Chronic stress is a universal condition commonly associated with many psychiatric diseases. An extensive body of evidence discussed hippocampal affection upon chronic stress exposure, however, the underlying molecular pathways still need to be identified. We investigated the impact of chronic stress on miR200/BMP/Olig-2 signaling and hippocampal myelination. We also compared the effects of chronic administration of amitriptyline and cholecalciferol on chronically stressed hippocampi. Both amitriptyline and cholecalciferol significantly decreased serum cortisol levels, reduced immobility time in the forced swim test, increased the number of crossed squares in open field test, decreased the hippocampal expression of bone morphogenetic protein 4 (BMP4) and its messenger RNA (mRNA) levels, reduced miR200 expression as compared to untreated chronically stressed rats. Also, both drugs amended the hippocampal neuronal damage, enhanced the surviving cell count, and increased the pyramidal layer thickness of Cornu Ammonis subregion 1 (CA1) and granule cell layer of the dentate gyrus. Cholecalciferol was more effective in increasing the area percentage of myelin basic protein (MBP) and Olig-2 positive cells count in hippocampi of chronic stress-exposed rats than amitriptyline, thus enhancing myelination. We also found a negative correlation between the expression of BMP4, its mRNA, miR200, and the immunoexpression of MBP and Olig-2 proteins. This work underscores the amelioration of the stress-induced behavioral changes, inhibition of miR200/BMP4 signaling, and enhancement of hippocampal myelination following chronic administration of either amitriptyline or cholecalciferol, though cholecalciferol seemed more effective in brain remyelination.

Lung cancer is one of the most prevalent human cancers with a high lethality rate worldwide. In this study, we demonstrated that GSE1 (genetic suppressor element 1) expression is aberrantly upregulated in lung adenocarcinoma and that GSE1 depletion inhibits the proliferation and migration of both A549 and H1299 cells. Immunoprecipitation assays demonstrated that GSE1 interacts with histone deacetylase 1 (HDAC1) and other BRAF–HDAC complex (BHC) components in cells. The transcriptome of GSE1-knockdown A549 cells indicated that 207 genes were upregulated and 159 were downregulated based on a p-value < .05 and fold change ≥ 1.5. Bioinformatics analysis suggested that 140 differentially expressed genes harbor binding sites for HDAC1, including the tumor suppressor gene KLF6 (Kruppel-like factor 6). Indeed, quantitative reverse-transcription polymerase chain reaction and western blot analysis revealed that GSE1 could inhibit the transcription of KLF6 in lung cancer cells. In conclusion, GSE1 cooperates with HDAC1 to promote the proliferation and metastasis of non-small cell lung cancer cells through the downregulation of KLF6 expression.

ErbB3-binding protein 1(Ebp1) has two isoforms, p42 Ebp1 and p48 Ebp1, both of which can regulate cell growth and differentiation. But these isoforms often have opposite effects, including contradictory roles in regulation of cell growth in different tissues and cells. P48 Ebp1 belongs to the full-length sequence, while conformational changes in the crystal structure of p42 Ebp1 reveals a lack of an α helix at the amino terminus. Due to the differences in the structures of these two isoforms, they have different binding partners and protein modifications. Ebp1 can function as both an oncogene and a tumor suppressor factor. However, the underlying mechanisms by which these two isoforms exert opposite functions are still not fully understood. In this review, we summarize the genes and the structures of protein of these two isoforms, protein modifications, binding partners and the association of different isoforms with diseases.