Decreased Cell Death Research Articles

MircoRNAs predict and modulate responses to chemotherapy in leukemic patients.

Leukemia covers a broad category of cancer malignancies that specifically affect bone marrow and blood cells. While different kinds of leukemia have been identified, effective treatments are still lacking for most forms, and even those treatments considered effective can lead to relapses. MicroRNAs, or miRNAs, are short endogenous non-coding single-stranded RNAs that help control the epigenetics of gene expression. Recently, a literature review proposed that miRNAs provided promising therapeutic targets for patients diagnosed with leukemia. Due to genetic abnormalities occurring during the maturation of white blood cells, studies commonly observed uncontrolled replication and decreased cell death, compared to healthy cells. This results in the activation of oncogenes, deactivation of tumor suppressor genes, and disruption of normal cellular functions. Although conventional cancer treatments significantly contribute to patient recovery, they can also impose many side effects. MiRNAs all significantly regulate angiogenesis, migration, apoptosis, carcinogenesis, and gene expression. Regarding chemotherapy, mounting research indicates that microRNAs may directly influence how responsive leukemia is to chemical treatments. This article reviews current studies on microRNAs, examining their influence on cancer advancement and spread, as well as their possible applications as diagnostic indicators and treatment targets in leukemia. Furthermore, we integrated the functions of microRNAs in cancer formation and progression with leukemia patient care, offering fresh insights into leukemia detection and management strategies.

Investigating the neuroprotective properties of Sargassum wightii extract against MPP+-induced apoptosis in SH-SY5Y human neuroblastoma cells.

This study aims to assess the neuroprotective effects of the methanolic extract of Sargassum wightii against oxidative stress and cell death induced by neurotoxins MPP + in SH-SY5Y cells. Briefly, the methanolic extract of S.wightii decreased the cytotoxicity of MPP + in SH-SY5Y cells. Treatment with S.wightii extract at a concentration of 400µg/ml resulted in a notable decrease in cell death, particularly in MPP + -induced cells. Flow cytometry analysis with annexin V/PI staining reveals apoptosis and necrosis in SH-SY5Y cell lines upon exposure to 1mM of MPP + . However, 100-400µg/ml concentrations of S.wightii extract effectively decrease apoptosis in SH-SY5Y cells. Furthermore, S.wightii inhibits caspase-3 activity, effectively shielding neuronal cells against MPP + -induced cell death. Mitochondrial membrane potential (MMP) assay using a JC-1 fluorescent probe indicates that the methanolic extract of S.wightii exhibits protective effects against MPP + -induced cell death and maintains mitochondrial membrane potential. Our results conclude that exposing SH-SY5Y cells to a methanolic extract of S.wightii could potentially increase the likelihood of inhibiting the cascade mechanism, stopping MPP+-induced apoptosis, and preventing the rupture of the mitochondrial membrane. However, the lack of low solubility and poor bioavailability reduce the therapeutic efficacy of S.wightii. Liposome-based drug delivery systems can improve the bioavailability and stability of bioactive compounds, enhancing their therapeutic potential. Hence, S.wightii may hold promise as an innovative treatment for neurological ailments.

Y-27632 and dual media culture approach promote the construction and transplantation of rabbit limbal epithelial cell sheets via cell spheroid culture and auto-bioprinting.

The shortage of corneal donors and the limitations in tissue engineering grafts, such as biocompatibility and mechanical properties, pose significant challenges in corneal transplantation. Here, for the first time, we investigate the effect of Rho kinase inhibitor Y-27632 and a dual media culture approach, including proliferative media (M1) and stabilizing media (M2), on rabbit limbal epithelial stem cells (LESCs), aiming to explore the feasibility of constructing corneal cell sheets in vitro through auto-bioprinting and assessing their corneal wound healing capacity in vivo. Y-27632 has primarily demonstrated significantly enhanced LESCs growth, proliferation, and reduced apoptosis. The dual media culture approach combined with Y-27632 improved LESCs proliferation while maintaining stemness. In spheroid culture, Y-27632 decreased cell death and promoted proliferation. Immunofluorescent staining and RNA sequencing revealed upregulation of genes related to tight junctions and cell adhesion and downregulation of genes associated with aging and cell cycle. Using a bioprinter, LESC spheroids were auto-bioprinted onto a custom-made curved collagen membrane, creating a bioactive, transplantable, tissue-engineered anterior corneal sheet. Anterior superficial corneal transplantation with these LESC sheets significantly accelerated epithelial wound healing in rabbit limbal stem cell deficiency (LSCD) models. Overall, the integration of Y-27632, dual-media culture, and spheroid cell culture led to the development of a highly bioactive and therapeutically promising bio-ink derived from LESCs. Auto-bioprinting these LESC spheroids produced a bioactive, transplantable corneal cell sheet, presenting a promising therapeutic option for LSCD. STATEMENT OF SIGNIFICANCE: The renewal and wound healing of the corneal epithelium are essential for maintaining normal vision and refractive function. Limbal stem cell deficiency (LSCD) is a major cause of blinding keratopathy, and current treatment options are limited. In this study, for the first time, we developed a highly bioactive and therapeutically potent bio-ink for ocular surface regeneration by integrating Y-27632, a dual-media culture approach, and spheroid cell culture. Additionally, using auto-bioprinting technology, the limbal epithelial stem cell (LESC) spheroid bio-ink was precisely auto-bioprinted onto the curved surface of the corneal membrane, significantly accelerating corneal epithelial healing in an LSCD rabbit model.

Galacto-oligosaccharides alone and combined with lactoferrin impact the Kenyan infant gut microbiota and epithelial barrier integrity during iron supplementation in vitro

Aim: Iron supplementation to African weaning infants was associated with increased enteropathogen levels. While cohort studies demonstrated that specific prebiotics inhibit enteropathogens during iron supplementation, their mechanisms remain elusive. Here, we investigated the in vitro impact of galacto-oligosaccharides (GOS) and iron-sequestering bovine lactoferrin (bLF) alone and combined on the gut microbiota of Kenyan infants during low-dose iron supplementation. Methods: Different doses of iron, GOS, and bLF were first screened during batch fermentations (n = 3), and the effect of these factors was studied on microbiota community structure and activity in the new Kenyan infant continuous intestinal PolyFermS model. The impact of different fermentation treatments on barrier integrity, enterotoxigenic Escherichia coli (ETEC) infection, and inflammatory response was assessed using a transwell co-culture of epithelial and immune cells. Results: A dose-dependent increase in short-chain fatty acid (SCFA) production, Bifidobacterium and Lactobacillus /Leuconostoc /Pediococcus (LLP) growth was detected with GOS alone and combined with bLF during iron supplementation in batches. This was confirmed in the continuous PolyFermS model, which also showed a treatment-induced inhibition of opportunistic pathogens C. difficile and C. perfringens . In all tests, supplementation of iron alone and combined with bLF did not have a significant effect on microbiota composition and activity. We observed a strengthening of the epithelial barrier and a decrease in cell death and pro-inflammatory response during ETEC infection with microbiota fermentation supernatants from iron + GOS, iron + bLF, and iron + GOS + bLF treatments compared to iron alone. Conclusion: Overall, beneficial effects on infant gut microbiota were shown using advanced in vitro models for GOS alone and combined with bLF during low-dose iron supplementation.

Cyclosorus terminans extract mitigates submandibular gland changes associated with high-fat diet consumption in male rats

ObjectivesTo investigate whether the prophylactic effect of Cyclosorus terminans extract mitigates metabolic impairment and submandibular gland changes, as indicated by increased aquaporin5 expression, decreased fibrosis, oxidative stress and inflammation, improved mitochondrial homeostasis/dynamics, and decreased cell death in the submandibular glands of high-fat diet (HFD)-feeding rats. MethodsThirty-two male Wistar rats were assigned to either a normal diet (ND) as control rats (n=8) or a HFD (n=24) for 12 weeks. The HFD-treated rats were divided into 3 subgroups to receive either: 1) vehicle (HDV), 2) Cyclosorus terminans at a dose of 100 mg/kg/d (HF100), or 3) Cyclosorus terminans at a dose of 200 mg/kg/d (HF200). At week 13, metabolic parameters, systemic oxidative stress, and submandibular gland parameters were assessed. ResultsTwelve weeks of HFD-feeding rats induced obese-insulin resistance and submandibular gland changes. Both HF100- and HF200-treated groups improved metabolic parameters and prevented gland changes by reducing fibrosis (TGF-β and p-38), malondialdehyde levels, inflammation (TNF-α, NF-κB, and Ifng), and cell death markers (Caspase 3, GSDMD, and MLKL). Both treatments supported balanced mitochondrial homeostasis/dynamics, as indicated by regulating related genes (Cpt1b, Ndufb8, Mfn1, Mfn2, Opa1, and Dnm1l). However, only the HF200-treated rats restored aquaporin-5 and antioxidants (SOD2 and GPX4) expression to control levels. ConclusionsCyclosorus terminans mitigates metabolic disturbances and submandibular gland changes in HFD-feeding rats. The high dose was more effective, improving gland function by increasing aquaporin5 and antioxidants. These results suggest Cyclosorus terminans may be a promising therapeutic for metabolic disturbances and submandibular gland changes in obese-insulin resistant patients.

Melatonin attenuates liver ischemia-reperfusion injury via inhibiting the PGAM5-mPTP pathway

Phosphoglycerate mutase/protein phosphatase (PGAM5)-mediated cell death plays an important role in multiple liver diseases. However, few studies have confirmed the regulatory mechanism of melatonin acting on PGAM5-mediated cell death in the context of liver ischemia-reperfusion (I/R) injury. The liver I/R injury model and cell hypoxia-reoxygenation model were established after melatonin pretreatment. Liver injury, cell activity, cell apoptosis, oxidative stress index, and PGAM5 protein expression were detected. To investigate the role of PGAM5 in melatonin-mediated liver protection during I/R injury, PGAM5 silencing, and overexpression were performed before melatonin pretreatment. Our results indicated that PGAM5 was significantly elevated by I/R injury, and predominantly localized in the necrosis area. However, treatment with melatonin blocked PGAM5 activation and conferred a survival advantage of hepatocytes in liver I/R injury, similar to the results achieved by silencing PGAM5. In terms of mechanism, we illustrated that activated PGAM5 promoted mitochondrial permeability transition pore (mPTP) opening, and administration of melatonin inhibited mPTP opening and interrupted hepatocytes death via blocking PGAM5. Our data indicated that the PGAM5-mPTP axis is responsible for I/R-induced liver injury. In contrast, melatonin supplementation blocked the PGAM5-mPTP axis and thus decreased cell death, providing a protective advantage to hepatocytes in I/R. These results established a new paradigm in melatonin-mediated hepatocyte protection under the burden of I/R attack.

Interplay between the SAFE and the sphingolipid pathway for cardioprotection

AimActivation of both the Survivor Activating Factor Enhancement (SAFE) pathway (including Tumor Necrosis Factor-alpha (TNF-α) and Signal Transducer and Activator of Transcription-3 (STAT-3)) and the sphingolipid signalling pathway (including sphingosine kinase-1 (SK1) and sphingosine-1 phosphate (S1P)) play a key role in promoting cardioprotection against ischemia-reperfusion injury (IRI). We investigated whether the activation of the SAFE pathway by exogenous S1P is dependent on the activation of SK1 for cardioprotection. Materials and methodsIsolated cardiomyocytes from TNF-α knockout (KO) mice, cardiomyocyte-specific STAT-3 KO mice and their wild-type (WT) littermates were exposed to simulated ischemia in the presence of a trigger of the SAFE pathway (S1P) and SK1 inhibitor (SK1-I). Similarly, isolated perfused hearts from adult TNF-α KO, STAT-3 KO and WT mice were subjected to IRI with S1P and/or SK1-I. Cell viability, infarct size (IS) and SK1 activity were assessed. Key findingsIn isolated cardiomyocytes and in isolated hearts subjected to simulated ischemia/IRI, S1P pretreatment decreased cell death in WT mice, an effect that was abrogated in the presence of SK1-I. S1P failed to reduce cell death after simulated ischemia/IRI in both cardiomyocytes or hearts isolated from TNF-α KO and STAT-3 KO mice. Interestingly, S1P pretreatment increased SK1 activity in WT and STAT-3 KO mice, with no changes in TNF-α KO mice. SignificanceOur data strongly suggest SK1 as a key component to activate STAT-3 downstream of TNF-α in the SAFE pathway, paving the way for the development of novel cardioprotective strategies that may target SK1 to modulate the SAFE pathway and increase cell survival following IRI.

A humanized monoclonal antibody targeting an ectonucleotidase rescues cardiac metabolism and heart function after myocardial infarction

Myocardial infarction (MI) results in aberrant cardiac metabolism, but no therapeutics have been designed to target cardiac metabolism to enhance heart repair. We engineer a humanized monoclonal antibody against the ectonucleotidase ENPP1 (hENPP1mAb) that targets metabolic crosstalk in the infarcted heart. In mice expressing human ENPP1, systemic administration of hENPP1mAb metabolically reprograms myocytes and non-myocytes and leads to a significant rescue of post-MI heart dysfunction. Using metabolomics, single-nuclear transcriptomics, and cellular respiration studies, we show that the administration of the hENPP1mAb induces organ-wide metabolic and transcriptional reprogramming of the heart that enhances myocyte cellular respiration and decreases cell death and fibrosis in the infarcted heart. Biodistribution and safety studies showed specific organ-wide distribution with the antibody being well tolerated. In humanized animals, with drug clearance kinetics similar to humans, we demonstrate that a single "shot" of the hENPP1mAb after MI is sufficient to rescue cardiac dysfunction.

Deubiquitinase JOSD1 tempers hepatic proteotoxicity

Derangements in protein homeostasis and associated proteotoxicity mark acute, chronic, and drug-induced hepatocellular injury. Metabolic dysfunction-associated proteasomal inhibition and the use of proteasome inhibitors often underlie such pathological hepatic proteotoxicity. In this study, we sought to identify a candidate deubiquitinating enzyme (DUB) responsible for reversing the proteotoxic damage. To this end, we performed a siRNA screening wherein 96 DUBs were individually knocked down in HepG2 cells under proteasomal inhibitor-induced stress for dual readouts, apoptosis, and cell viability. Among the putative hits, we chose JOSD1, a member of the Machado-Josephin family of DUBs that reciprocally increased cell viability and decreased cell death under proteotoxicity. JOSD1-mediated mitigation of proteotoxicity was further validated in primary mouse hepatocytes by gain and loss of function studies. Marked plasma membrane accumulation of monoubiquitinated JOSD1 in proteotoxic conditions is a prerequisite for its protective role, while the enzymatically inactive JOSD1 C36A mutant was conversely polyubiquitinated, does not have membrane localisation and fails to reverse proteotoxicity. Mechanistically, JOSD1 physically interacts with the suppressor of cytokine signalling 1 (SOCS1), deubiquitinates it and enhances its stability under proteotoxic stress. Indeed, SOCS1 expression is necessary and sufficient for the hepatoprotective function of JOSD1 under proteasomal inhibition. In vivo, adenovirus-mediated ectopic expression or depletion of JOSD1 in mice liver respectively protects or aggravates hepatic injury when challenged with proteasome blocker Bortezomib. Our study thus unveils JOSD1 as a potential candidate for ameliorating hepatocellular damage in liver diseases.

KSHV ORF20 Promotes Coordinated Lytic Reactivation for Increased Infectious Particle Production.

Kaposi's sarcoma-associated herpesvirus (KSHV) is a cancer-causing virus that establishes life-long infection. KSHV is implicated in the etiology of Kaposi's sarcoma, and a number of rare hematopoietic malignancies. The present study focuses on the KSHV open reading frame 20 (ORF20), a member of the conserved herpesvirus UL24 protein family containing five conserved homology domains and a conserved PD-(D/E)XK putative endonuclease motif, whose nuclease function has not been established to date. ORF20 encodes three co-linear protein isoforms, full length, intermediate, and short, though their differential functions are unknown. In an effort to determine the role of ORF20 during KSHV infection, we generated a recombinant ORF20-Null KSHV genome, which fails to express all three ORF20 isoforms. This genome was reconstituted in iSLK cells to establish a latent infection, which resulted in an accelerated transcription of viral mRNAs, an earlier accumulation of viral lytic proteins, an increase in the quantity of viral DNA copies, and a significant decrease in viral yield upon lytic reactivation. This was accompanied by early cell death of cells infected with the ORF20-Null virus. Functional complementation of the ORF20-Null mutant with the short ORF20 isoform rescued KSHV production, whereas its endonuclease mutant form failed to enhance lytic reactivation. Complementation with the short isoform further revealed a decrease in cell death as compared with ORF20-Null virus. Finally, expression of IL6 and CXCL8, previously shown to be affected by the hCMV UL24 homolog, was relatively low upon reactivation of cells infected with the ORF20-Null virus. These findings suggest that ORF20 protein, with its putative endonuclease motif, promotes coordinated lytic reactivation for increased infectious particle production.

Melatonin alleviates heme-induced ferroptosis via activating the Nrf2/HO-1 pathway in neurons.

Ferroptosis of neurons is a significant cause of brain injury following intracerebral hemorrhage (ICH). As an iron-containing compound in hemoglobin, heme contributes to nerve injury post-ICH. Melatonin has been shown to mitigate the effects of ICH, yet its specific functions remain largely elusive. In this study, we aimed to explore the roles and mechanisms of melatonin in heme-induced ferroptosis subsequent to ICH. C57BL/6 mice were intracranially injected with heme and then treated with melatonin. Behavior tests [modified neurological severity score (mNSS), forelimb placing, and corner turn tests], H&E staining, Nissl staining, and Prussian blue staining were used to evaluate mouse brain tissue injury. In vitro, HT-22 cells were stimulated with heme and cell viability was determined by crystal violet staining. The iron contents were determined in heme-treated brains and cells, and the levels of 4-hydroxynonenal (4-HNE) and malonaldehyde (MDA) were assessed by ELISA. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to investigate the mRNA levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Immunoblotting was used to analyze the protein expression of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), Nrf2, and HO-1. Finally, small interfering RNA (siRNA) was used to knock down Nrf2 in HT-22 cells. Melatonin treatment alleviated heme-induced injuries to neural function, as indicated by improved behavior in the mice. Moreover, melatonin decreased cell death and iron concentrations, increased MDA and 4-HNE levels, and reversed the decreases in GPX4, SLC7A11, Nrf2, and HO-1 induced by heme in vitro and in vivo. These results indicated that melatonin could improve the ferroptosis induced by heme. In addition, we found that Nrf2 knockdown attenuated the therapeutic effect of melatonin on neuronal ferroptosis induced by heme. In general, melatonin alleviates heme-induced ferroptosis by activating the Nrf2/HO-1 pathway, which implies that melatonin is a promising treatment for ferroptosis in ICH.

Vascular tissues bioprinted with smooth muscle cell-only bioinks in support baths mimic features of native coronary arteries

This study explores the bioprinting of a smooth muscle cell-only bioink into ionically crosslinked oxidized methacrylated alginate (OMA) microgel baths to create self-supporting vascular tissues. The impact of OMA microgel support bath methacrylation degree and cell-only bioink dispensing parameters on tissue formation, remodeling, structure and strength was investigated. We hypothesized that reducing dispensing tip diameter from 27 G (210μm) to 30 G (159μm) for cell-only bioink dispensing would reduce tissue wall thickness and improve the consistency of tissue dimensions while maintaining cell viability. Printing with 30 G tips resulted in decreased mean wall thickness (318.6μm) without compromising mean cell viability (94.8%). Histological analysis of cell-only smooth muscle tissues cultured for 14 d in OMA support baths exhibited decreased wall thickness using 30 G dispensing tips, which correlated with increased collagen deposition and alignment. In addition, a TUNEL assay indicated a decrease in cell death in tissues printed with thinner (30 G) dispensing tips. Mechanical testing demonstrated that tissues printed with a 30 G dispensing tip exhibit an increase in ultimate tensile strength compared to those printed with a 27 G dispensing tip. Overall, these findings highlight the importance of precise control over bioprinting parameters to generate mechanically robust tissues when using cell-only bioinks dispensed and cultured within hydrogel support baths. The ability to control print dimensions using cell-only bioinks may enable bioprinting of more complex soft tissue geometries to generatein vitrotissue models.

MOF-818 Nanozyme Suppresses Calcium Oxalate Kidney Stones by Alleviating Oxidative Stress and Inflammatory Injury.

There remains a lack of effective drugs to alleviate the kidney stones caused by oxidative stress and inflammatory damage. The MOF-818 nanozyme is utilized to lessen the generation of reactive oxygen species (ROS) effectively, restore the membrane potential of mitochondria, regulate the cell cycle, decrease cell death, hinder the recruitment of macrophages, and mitigate the release of inflammatory factors in macrophages. These effects are attributed to the nanozyme's ability to mimic the enzyme properties of catalase (CAT) and superoxide dismutase (SOD). It is demonstrated that this nanozyme can reduce kidney calcium oxalate crystal deposition by reducing the renal injury caused by high concentration oxalate, upregulate the expression levels of SOD and CAT in tissues, downregulate adhesion proteins and inflammatory factor IL-6 and TNF-α, and promote the polarization of macrophages from M1 to M2 phenotype in the rat model induced by ethylene glycol. Overall, MOF-818 has the potential to effectively suppress oxidative stress and inflammatory harm caused by high levels of oxalate, hence lowering the likelihood of stone formation. MOF-818 nanozyme is also expected to be used as an alternative drug for the treatment of calcium oxalate kidney stones and provide an experimental theoretical basis for the development of new nanomedicines.

Beneficial effects of the Achillea millefolium green-formulated zinc nanoparticles in mice with heart failure following myocardial infarction

Myocardial infarction is a significant contributor to illness and death on a global scale. Limited advancements have been made in regenerative therapies due to the inadequate natural regeneration of the adult mammalian myocardium and difficulties in drug delivery. Nanocarriers such as exosomes, nanoparticles, and liposomes present numerous potential benefits for treating myocardial infarction, such as enhanced drug delivery, extended, and retention therapeutic effects. Nevertheless, numerous obstacles have hindered the extensive clinical application of these technologies. Zinc nanoparticles (Zn NPs) are frequently used in the healthcare industry, specifically in cardiovascular treatments. The research documented a sustainable method for synthesizing Zn NPs by Achillea millefolium extract, utilizing eco-friendly practices. Ultraviolet–visible (UV–VIS) spectrophotometry, field emission scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR) were utilized to examine the Zn NPs, while also exploring their potential in treating myocardial infarction. The Achillea millefolium extract contains tannin at 16.49 %, phenols at 39.19 %, saponin at 14.21 %, steroids at 22.84 %, flavonoids at 7.11 %, and alkaloids at 0.16 %. The animals were classified into three separate groups: (1) isoproterenol; (2) control; (3) Zn NPs + isoproterenol (100 μg/ml). Mice were given isoproterenol to induce myocardial infarction. Real-time PCR and western blot techniques were employed to quantify the activation of PPAR-Υ/NF-κB and the subsequent release of cytokines induced by lipopolysaccharide. Following the administration of varying doses of Zn NPs, the assessment of cardiac function was carried out through biochemical, histochemical, and electrocardiogram (ECG) analysis. The nanoparticles displayed a round shape when they were created. Recent research indicates that Zn NPs exhibit cardioprotective characteristics against myocardial infarction, potentially by suppressing NF-κB signaling and stimulating PPAR-γ. Zn NPs administration led to a reduction in interleukin 6 (IL-6), IL-1β, and TNF-α in the mice hearts. The use of Zn NPs notably decreased cell death and inflammatory cytokines expression. The beneficial impacts of Zn NPs may potentially stem from the gene expression normalization in PPAR-Υ/NF-κB/ΙκB-α/ΙΚΚα/β and PPAR-Υ phosphorylation pathways. The levels of myocardial injury markers are significantly inhibited by Zn NPs, leading to a reduction in mortality rates and an amelioration in the ventricular wall infarction condition. Furthermore, the administration of Zn NPs effectively prevents the characteristic ST segment depression observed in animals with myocardial infarction.

Resveratrol Mitigates Cognitive Impairments and Cholinergic Cell Loss in the Medial Septum in a Mouse Model of Gradual Cerebral Hypoperfusion.

Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia. There is currently no effective treatment for VCID. Resveratrol (RSV) is considered an antioxidant; however, our group has observed pleiotropic effects in stroke paradigms, suggesting more effects may contribute to mechanistic changes beyond antioxidative properties. The main goal of this study was to investigate if administering RSV twice a week could alleviate cognitive declines following the induction of a VCID model. Additionally, our aim was to further describe whether this treatment regimen could decrease cell death in brain areas vulnerable to changes in cerebral blood flow, such as the hippocampus and medial septum. We hypothesized RSV treatments in a mouse model of gradual cerebral hypoperfusion protect against cognitive impairment. We utilized gradual bilateral common carotid artery stenosis (GBCCAS) via the surgical implantation of ameroid constrictor devices. RSV treatment was administered on the day of implantation and twice a week thereafter. Cerebral perfusion was measured by laser speckle contrast imaging, and cognitive functions, including the recognition memory, the spatial working memory, and associative learning, were assessed by novel object recognition (NOR), Y-maze testing, and contextual fear conditioning (CFC), respectively. RSV treatment did not alleviate cerebral perfusion deficits but mitigated cognitive deficits in CFC and NOR after GBCCAS. Despite these deficits, no hippocampal pathology was observed; however, cholinergic cell loss in the medial septum was significantly increased after GBCCAS. This cholinergic cell loss was mitigated by RSV. This study describes a novel mechanism by which chronic RSV treatments protect against a VCID-induced cognitive decline through the preservation of cholinergic cell viability to improve memory performance.

Abstract Mo014: Cardioactive molecules identified by functional in vivo screening prevent anthracycline cardiotoxicity

Introduction: Promotion of cardiomyocyte survival upon insult is mandatory to allow maintenance of ventricular function and dam development of severe heart dysfunction. Recently, through an in vivo functional screening of the mouse secretome we identified potent mediators of cardiomyocyte survival among 1200 soluble factors expressed by AAV vectors. The cardiac overexpression of the most effective cytokines (Chrdl1, Fam3c and Fam3b) maintained cardiac function after myocardial infarction by blunting oxidative damage, decreasing cell death, promoting autophagy, and inhibiting myofibroblast activation (Ruozi, Bortolotti et al. 2022. Sci Transl Med 14, eabo0699) Aim: We investigated the effect of cardioactive proteins in a mouse anthracycline model of cardiotoxicity. Material and Methods: Mimicking clinical chronic therapeutic regimens, doxorubicin (24 mg/kg) was administered to C57/BL6 female mice one week after AAV9-driven cardiac overexpression of Chrdl1, Fam3b or Fam3c. Echocardiography was performed after 6 and 8 weeks and was followed by histology and molecular analysis. Apoptosis, autophagy and mitochondrial function was analysed in primary cardiomyocytes along with pathway investigation. Results: AAV9-mediated overexpression of Chrdl1, Fam3b and Fam3c markedly improved animal survival. Echocardiographic assessment revealed significant reduction of left ventricular ejection fraction and marked heart dilatation in control animals, while all treated animals maintained functional and anatomical parameters. Treated mice showed normal cardiac mass and cardiomyocyte cross-sectional area, reduced interstitial collagen deposition and decreased expression of profibrotic genes. In both rodents and human cardiomyocytes, Chrdl1, Fam3b and Fam3c factors decreased doxorubicin induced apoptosis, induced protective macroautophagy and preserved mitochondrial morphology. Chrdl1 prevented doxorubicin-mediated BMP upregulation and autophagy engulfment through the inhibition of a detrimental molecular pathway downstream the BMP receptor. Conclusions: The development of biotherapeutics that act as pro-survival factors for cardiomyocytes offers significant translational perspectives in cardio-oncology.

Missense Mutations in Myc Box I Influence Nucleocytoplasmic Transport to Promote Leukemogenesis.

Somatic missense mutations in the phosphodegron domain of the MYC gene (MYC Box I or MBI) are detected in the dominant clones of a subset of patients with acute myeloid leukemia (AML), but the mechanisms by which they contribute to AML are unknown. To investigate the effects of MBI MYC mutations on hematopoietic cells, we employed a multi-omic approach to systematically compare the cellular and molecular consequences of expressing oncogenic doses of wild type, threonine-58 and proline-59 mutant MYC proteins in hematopoietic cells, and we developed a knockin mouse harboring the germline MBI mutation p.T58N in the Myc gene. Both wild-type and MBI mutant MYC proteins promote self-renewal programs and expand highly selected subpopulations of progenitor cells in the bone marrow. Compared with their wild-type counterparts, mutant cells display decreased cell death and accelerated leukemogenesis in vivo, changes that are recapitulated in the transcriptomes of human AML-bearing MYC mutations. The mutant phenotypes feature decreased stability and translation of mRNAs encoding proapoptotic and immune-regulatory genes, increased translation of RNA binding proteins and nuclear export machinery, and distinct nucleocytoplasmic RNA profiles. MBI MYC mutant proteins also show a higher propensity to aggregate in perinuclear regions and cytoplasm. Like the overexpression model, heterozygous p.T58N knockin mice displayed similar changes in subcellular MYC localization, progenitor expansion, transcriptional signatures, and develop hematopoietic tumors. This study uncovers that MBI MYC mutations alter RNA nucleocytoplasmic transport mechanisms to contribute to the development of hematopoietic malignancies.

Cardioprotective effects of nanoparticles green formulated by Spinacia oleracea extract on isoproterenol-induced myocardial infarction in mice by the determination of PPAR-γ/NF-κB pathway

Abstract We developed a contemporary cardioprotective medication using silver nanoparticles (AgNPs) loaded with Spinacia oleracea to treat isoproterenol (ISO)-induced myocardial infarction in mice, focusing on the PPAR-γ/NF-κB pathway. The physicochemical techniques, such as Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet–visible spectroscopy, and energy dispersive X-ray analysis, were employed to characterize the AgNPs. In the in vivo experiment, myocardial infarction was induced in mice by administering ISO subcutaneously at a dose of 40 mg/kg every 12 h for a total of three times. The mice were divided into five groups in a random manner: (1 and 2) ISO + AgNPs at varying doses (10 and 20 μg/mL) and time points; (3) ISO; and (4) control. Following the treatment, cardiac function was assessed through electrocardiogram, as well as biochemical and histochemical analyses. In the study, we examined the inflammatory reactions and cell death in human coronary artery endothelial cells exposed to lipopolysaccharide (LPS). The PPAR-γ/NF-κB activation by LPS and the resulting cytokine production were checked using real-time PCR and western blot techniques. The typical ST segment depression in myocardial infarction mice is significantly inhibited by the administration of AgNPs. Additionally, the treatment with AgNPs leads to a significant improvement in ventricular wall infarction, a decrease in mortality rate, and inhibition of myocardial injury marker levels. Furthermore, the application of AgNPs resulted in a decrease in the inflammatory environment within the hearts of mice with myocardial infarction. This effectively prevented the increase in TNF-α, IL-1β, and IL-6. The gene expression normalization of PPAR-γ/NF-κB/IκB-α/IKKα/β and PPAR-γ phosphorylation could potentially be linked to the advantageous impacts of AgNPs. In the context of an in vitro experiment, the administration of AgNPs demonstrated a notable decrease in cell death and inflammation cytokines expression inhibition. The myocardial infarction mice in the pre + post-ISO group appear to experience more noticeable cardioprotective effects from the treatment with AgNPs than those in the post-ISO group. Our research findings demonstrate that AgNPs possess cardioprotective efficacies in ISO-induced myocardial infarction. This beneficial effect may be attributed to the PPAR-γ activation and the NF-κB signaling inhibition. Consequently, our study presents a novel remedial approach for myocardial infarction treatment in clinical settings.

Insights into brominated flame retardant neurotoxicity: mechanisms of hippocampal neural cell death and brain region-specific transcriptomic shifts in mice.

Brominated flame retardants (BFRs) reduce flammability in a wide range of products including electronics, carpets, and paint, but leach into the environment to result in continuous, population-level exposure. Epidemiology studies have correlated BFR exposure with neurological problems, including alterations in learning and memory. This study investigated the molecular mechanisms mediating BFR-induced cell death in hippocampal cells and clarified the impact of hexabromocyclododecane (HBCD) exposure on gene transcription in the hippocampus, dorsal striatum, and frontal cortex of male mice. Exposure of hippocampus-derived HT-22 cells to various flame retardants, including tetrabromobisphenol-A (current use), HBCD (phasing out), or 2,2',4,4'-tetrabromodiphenyl ether (BDE-47, phased out) resulted in time, concentration, and chemical-dependent cellular and nuclear morphology alterations, alterations in cell cycle and increases in annexin V staining. All 3 BFRs increased p53 and p21 expression; however, inhibition of p53 nuclear translocation using pifthrin-α did not decrease cell death. Transcriptomic analysis upon low (10 nM) and cytotoxic (10 μM) BFR exposure indicated that HBCD and BDE-47 altered genes mediating autophagy-related pathways. Further evaluation showed that BFR exposure increased LC3-II conversion and autophagosome/autolysosome formation, and co-exposure with the autophagy inhibitor 3-methyladenine (3-MA) attenuated cytotoxicity. Transcriptomic assessment of select brain regions from subchronically HBCD-exposed male mice demonstrated alteration of genes mediating vesicular transport, with greater impact on the frontal cortex and dorsal striatum compared with the dorsal and ventral hippocampus. Immunoblot analysis demonstrated no increases in cell death or autophagy markers, but did demonstrate increases in the SNARE binding complex protein SNAP29, specifically in the dorsal hippocampus. These data demonstrate that BFRs can induce chemical-dependent autophagy in neural cells in vitro and provide evidence that BFRs induce region-specific transcriptomic and protein expression in the brain suggestive of changes in vesicular trafficking.

The affinity of cellulose nanoparticle toward hydrogel based on chitosan/tragacanth for radiation protection: Study of pulmonary damages on rats

AbstractIn order to overcome the harmful effects of radiation exposure on lung tissue in radiation therapy, a complete comparative analysis was performed between the injectable pure hydrogel and a novel composite hydrogel, taking into account the addition of cellulose nanoparticles in varying ratios. Initially, both chitosan and tragacanth hydrogels were chemically were modified, and then characterized by FTIR spectroscopy and rheology measurement. For in vivo studies, 42 rats were divided into seven groups. Rats in group 1, were not exposed to radiation, and no injection was done. Rats in group 2 were exposed to a radiation dose of 15 Gy without any injection. Rats in groups 3, 4, and 5 got injectable chitosan/ tragacanth hydrogel containing nanocellulose 25, 50, and 75 mg/kg BW, respectively, along with a radiation dose of 15 Gy. Rats in group 6 got a radiation dose of 15 Gy and an IP injection optimal dose of cellulose nanoparticle and PBS. Rat in group 7 got a radiation dose of 15 Gy and an IP injection of hydrogel containing only chitosan–tragacanth. The pathological results demonstrated that the 25 mg/kg BW dose of nanocellulose‐contained hydrogel possessed less inflammation, mucus secretion, bleeding in lung tissue, and air sac wall thickening than other groups. In addition, a biochemistry assessment was conducted by examining the activity of three enzymes of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxide (GPx), which findings confirmed the hydrogel incorporated with 25 mg/kg BW dose of nanocellulose decreased cell death in a lung tissue damaged by radiation which was 52 IU/mL, 37 IU/mL, and 10 μM in comparison with 63 IU/mL, 40 IU/mL, and 1 μM for the control sample.