Cell Biochemistry and Function最新文献

High rate of relapse, following chemotherapy, in acute myeloid leukemia (AML) is a major concern. The chemoprotection conferred by the bone marrow microenvironment has lately been recognized, in addition to autophagy-mediated chemoresistance. Thus, the present study explored the effect of osteoblast on autophagy in AML and its impact on sensitivity to cytarabine (Ara-C) in the context of endosteal niche. Co-culture of KG1-a, HL60, or THP-1 AML cells with osteoblastic Saos-2 cell line induced autophagy in AML cell lines under direct contact. HL60 cells when co-culture with Saos-2 demonstrated more resistance to Ara-C induced apoptosis, which was reversed upon chloroquine treatment. Similarly, inhibition of autophagy in AML cell by knocking down Beclin-1 enhanced HL60 sensitivity to Ara-C. An interesting observation was upregulation of autophagy even in Saos-2 cells upon co-culture with AML cell, and increase in HL60 apoptosis in response to Ara-C on Beclin-1 knockdown in osteoblast cell. This highlights that autophagy plays a chemoprotective role in the endosteal niche in AML against Ara-C.

Epigallocatechin-gallate (EGCG), the predominant catechin in green tea, is a key constituent of tea polyphenols. Due to the EGCG's diverse biological activities of anti-inflammatory, antioxidant, and so forth, green tea is believed to exert a positive influence on a variety of diseases. And extensive research had uncovered a range of protective effects attributed to EGCG, indicating its potential to mitigate various pathological conditions. The precise mechanisms through which EGCG operates remain a subject of ongoing discussion among researchers. Reactive oxygen species (ROS), a primary culprit in oxidative stress, have been demonstrated to be reduced by EGCG. Furthermore, nuclear factor kappa-B (NF-κB), a pivotal signal molecular of inflammation progress, has been observed to be suppressed by EGCG. Sirtuins1 (Sirt1) is a histone deacetylase, the obligate substrate of which is NAD+. Evidence suggests that EGCG can enhance the activities of Sirt1 to induce autophagy to protect inflammation injury and oxidative stress in tissues and organs. Despite the promising protective effects of EGCG, its clinical use is constrained by its limited bioavailability. This review aims to consolidate the existing evidence and elucidate the mechanisms that support EGCG's protective role, as well as to explore the challenges and potential strategies for its clinical application.

Prostate cancer (PCa) is the most commonly detected malignancy in men worldwide. PCa is a slow-growing cancer with the absence of symptoms at early stages. The pathogenesis has not been entirely understood including the key risk factors related to PCa development like diet and microbiota derived metabolites. Microbiota may influence the host's immunological responses, inflammatory responses, and metabolic pathways, which may be crucial for the development and metastasis. Similarly, short-chain fatty acids, methylamines, hippurate, bile acids, and other metabolites generated by microbiota may have potential roles in cancer inflammation and progression of cancer. Most studies have focused on the role of metabolites and their pathways involved in chronic inflammation, tumor initiation, proliferation, and progression. In summary, the review discusses the role of microbiota and microbial-derived metabolite-built strategies in inflammation and progression of the PCa.

Hexanucleotide repeat expansions in C9orf72 are the most common genetic mutation associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9-ALS/FTD). Dipeptide repeat (DPR) proteins, such as poly(proline–arginine) (polyPR) generated from G4C2 repeat expansions, have been shown to be highly toxic. In this study, PR20 was labeled with fluorescein isothiocyanate (FITC) to track its cellular localization. Several cell lines demonstrated survival under PR20 treatment by sequestering PR20 in the cytoplasm. Treatment with JQ-1 or Ivermectin (Iver) translocated PR20 into the nucleus, leading to cell death. Mechanistically, KPNA2/KPNB1 interacted with PR20 in the cytoplasm and hindered PR20 from entering the cell nucleus. Genetic silencing of KPNA2/KPNB1 converted PR20-resistant cells into PR20-sensitive cells. Treatment with JQ1 significantly reduced the protein levels of KPNA2/KPNB1, allowing PR20 to enter the nucleus. Overexpression of KPNA2 or KPNB1 effectively blocked cell death induced by co-treatment with JQ-1 and PR20. Our results indicate that super-enhancers shield cells from PR20 toxicity by upregulating the expression of KPNA2/KPNB1.

Increased oxidative stress and apoptosis are key mechanisms of thymic atrophy induced by cyclophosphamide (CYP). Atrophy leads to changes in the thymic microenvironment and disrupts T cell maturation. The hormone melatonin displays antioxidant and antiapoptotic effects. Here, we tested the hypothesis that melatonin would act as a cytoprotective agent against the harmful effects of CYP in the thymus. A single dose of CYP (300 mg/kg; ip) was injected in male C57BL/6 mice pretreated or not with melatonin (10 mg/kg/day, ip) for 4 days. Atrophy, oxidative stress and apoptosis markers, and T cell subpopulations were evaluated in the thymus 24 h after CYP injection. Melatonin partially prevented atrophy and the increase in caspase 3 activity induced by CYP. Augmented lipoperoxidation and generation of NADPH-oxidase derived superoxide (O₂^•−), as well as decreased superoxide dismutase (SOD) activity, were detected in the thymus of CYP-injected mice. Pretreatment with melatonin abrogated these responses. CYP reduced the number of double-positive (CD4⁺CD8⁺) cells, activated single-positive (CD8⁺ and CD4⁺) cells, and regulatory CD4⁺FoxP3⁺ (Treg) cells in the thymus. None of these effects were reversed by melatonin. In conclusion, melatonin partially prevented thymic atrophy, possibly by reducing apoptosis and oxidative stress. However, melatonin did not abrogate the immunomodulatory effect of CYP on T cell populations. The lack of effect of melatonin on CYP-induced reduction in Treg cells may be of interest since these cells reduce antitumor immunity.

The present study aimed to optimize a mouth-dissolving film (MDF) made from Pongamia pinnata stem bark extract to increase patient compliance and accelerate oral disease therapy. Several stem bark extracts were prepared, and karanjin was used as an herbal marker for the extracts. The ethanolic extract showed the maximum yield (12.10% ± 0.09%) and cytotoxic activity against human oral cancer (KB 3-1) and embryonic kidney cell lines. The MDF formulation was focused on incorporating a fixed amount of the extract and varying concentrations of HPMC E5 polymer, along with evaluating the performance of plasticizers like PEG 400 and propylene glycol (PG). An optimized formulation was determined based on disintegration time, wetting time, and folding endurance. The formulation consisted of HPMC E5 as a film-forming polymer, PG as a superior plasticizer, ascorbic acid as an antioxidant, and other ingredients contributing to solubility, dispersion, sweetening, and appearance. High-performance thin-layer chromatography-mass spectrometry analysis confirmed higher levels of karanjin in the optimized formulation, ensuring its successful incorporation and stability. Taste masking evaluations indicate a favorable taste profile and a high potential for patient compliance. The stability study displayed no significant changes in the physical characteristics of the film, affirming its stability and quality. In conclusion, the developed herbal-based optimized MDF presents a promising drug delivery system, offering enhanced patient compliance, taste masking, and stability. The MDF holds great potential for effective treatment and management of oral diseases, providing convenience and improved therapeutic outcomes.

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, is extensively expressed in diverse human organs and plays a pivotal role in mediating the onset, progression, and severity of numerous diseases. Recent research has explored the substantial impact of AhR on skin homeostasis and related pathologies. As a multi-layered organ, the skin comprises multiple cell populations that express AhR. In this review, we introduce the role of AhR in various skin cells and its impact on skin barrier function. Furthermore, we explore the involvement of AhR in the development of various skin diseases, highlighting its potential as a therapeutic target for skin disorders. By targeting AhR, we may open new avenues for the development of novel and efficient skin disease treatments.